Greg Kroah-Hartman | b244131 | 2017-11-01 15:07:57 +0100 | [diff] [blame] | 1 | // SPDX-License-Identifier: GPL-2.0 |
Christoph Lameter | b20a350 | 2006-03-22 00:09:12 -0800 | [diff] [blame] | 2 | /* |
Hugh Dickins | 14e0f9b | 2015-11-05 18:49:43 -0800 | [diff] [blame] | 3 | * Memory Migration functionality - linux/mm/migrate.c |
Christoph Lameter | b20a350 | 2006-03-22 00:09:12 -0800 | [diff] [blame] | 4 | * |
| 5 | * Copyright (C) 2006 Silicon Graphics, Inc., Christoph Lameter |
| 6 | * |
| 7 | * Page migration was first developed in the context of the memory hotplug |
| 8 | * project. The main authors of the migration code are: |
| 9 | * |
| 10 | * IWAMOTO Toshihiro <iwamoto@valinux.co.jp> |
| 11 | * Hirokazu Takahashi <taka@valinux.co.jp> |
| 12 | * Dave Hansen <haveblue@us.ibm.com> |
Christoph Lameter | cde5353 | 2008-07-04 09:59:22 -0700 | [diff] [blame] | 13 | * Christoph Lameter |
Christoph Lameter | b20a350 | 2006-03-22 00:09:12 -0800 | [diff] [blame] | 14 | */ |
| 15 | |
| 16 | #include <linux/migrate.h> |
Paul Gortmaker | b95f1b31 | 2011-10-16 02:01:52 -0400 | [diff] [blame] | 17 | #include <linux/export.h> |
Christoph Lameter | b20a350 | 2006-03-22 00:09:12 -0800 | [diff] [blame] | 18 | #include <linux/swap.h> |
Christoph Lameter | 0697212 | 2006-06-23 02:03:35 -0700 | [diff] [blame] | 19 | #include <linux/swapops.h> |
Christoph Lameter | b20a350 | 2006-03-22 00:09:12 -0800 | [diff] [blame] | 20 | #include <linux/pagemap.h> |
Christoph Lameter | e23ca00 | 2006-04-10 22:52:57 -0700 | [diff] [blame] | 21 | #include <linux/buffer_head.h> |
Christoph Lameter | b20a350 | 2006-03-22 00:09:12 -0800 | [diff] [blame] | 22 | #include <linux/mm_inline.h> |
Pavel Emelyanov | b488893 | 2007-10-18 23:40:14 -0700 | [diff] [blame] | 23 | #include <linux/nsproxy.h> |
Hugh Dickins | e9995ef | 2009-12-14 17:59:31 -0800 | [diff] [blame] | 24 | #include <linux/ksm.h> |
Christoph Lameter | b20a350 | 2006-03-22 00:09:12 -0800 | [diff] [blame] | 25 | #include <linux/rmap.h> |
| 26 | #include <linux/topology.h> |
| 27 | #include <linux/cpu.h> |
| 28 | #include <linux/cpuset.h> |
Christoph Lameter | 04e62a2 | 2006-06-23 02:03:38 -0700 | [diff] [blame] | 29 | #include <linux/writeback.h> |
Christoph Lameter | 742755a | 2006-06-23 02:03:55 -0700 | [diff] [blame] | 30 | #include <linux/mempolicy.h> |
| 31 | #include <linux/vmalloc.h> |
David Quigley | 86c3a76 | 2006-06-23 02:04:02 -0700 | [diff] [blame] | 32 | #include <linux/security.h> |
Hugh Dickins | 42cb14b | 2015-11-05 18:50:05 -0800 | [diff] [blame] | 33 | #include <linux/backing-dev.h> |
Minchan Kim | bda807d | 2016-07-26 15:23:05 -0700 | [diff] [blame] | 34 | #include <linux/compaction.h> |
Adrian Bunk | 4f5ca26 | 2008-07-23 21:27:02 -0700 | [diff] [blame] | 35 | #include <linux/syscalls.h> |
Dominik Brodowski | 7addf44 | 2018-03-17 16:08:03 +0100 | [diff] [blame] | 36 | #include <linux/compat.h> |
Naoya Horiguchi | 290408d | 2010-09-08 10:19:35 +0900 | [diff] [blame] | 37 | #include <linux/hugetlb.h> |
Aneesh Kumar K.V | 8e6ac7f | 2012-07-31 16:42:27 -0700 | [diff] [blame] | 38 | #include <linux/hugetlb_cgroup.h> |
Tejun Heo | 5a0e3ad | 2010-03-24 17:04:11 +0900 | [diff] [blame] | 39 | #include <linux/gfp.h> |
Jérôme Glisse | df6ad69 | 2017-09-08 16:12:24 -0700 | [diff] [blame] | 40 | #include <linux/pfn_t.h> |
Jérôme Glisse | a5430dd | 2017-09-08 16:12:17 -0700 | [diff] [blame] | 41 | #include <linux/memremap.h> |
Jérôme Glisse | 8315ada | 2017-09-08 16:12:21 -0700 | [diff] [blame] | 42 | #include <linux/userfaultfd_k.h> |
Rafael Aquini | bf6bddf1 | 2012-12-11 16:02:42 -0800 | [diff] [blame] | 43 | #include <linux/balloon_compaction.h> |
Vladimir Davydov | 33c3fc7 | 2015-09-09 15:35:45 -0700 | [diff] [blame] | 44 | #include <linux/page_idle.h> |
Vlastimil Babka | d435edc | 2016-03-15 14:56:15 -0700 | [diff] [blame] | 45 | #include <linux/page_owner.h> |
Ingo Molnar | 6e84f31 | 2017-02-08 18:51:29 +0100 | [diff] [blame] | 46 | #include <linux/sched/mm.h> |
Linus Torvalds | 197e7e5 | 2017-08-20 13:26:27 -0700 | [diff] [blame] | 47 | #include <linux/ptrace.h> |
Ralph Campbell | 34290e2 | 2020-01-30 22:14:44 -0800 | [diff] [blame] | 48 | #include <linux/oom.h> |
Dave Hansen | 884a6e5 | 2021-09-02 14:59:09 -0700 | [diff] [blame] | 49 | #include <linux/memory.h> |
Baolin Wang | ac16ec8 | 2022-01-14 14:08:43 -0800 | [diff] [blame] | 50 | #include <linux/random.h> |
Huang Ying | c574bbe | 2022-03-22 14:46:23 -0700 | [diff] [blame] | 51 | #include <linux/sched/sysctl.h> |
Aneesh Kumar K.V | 467b171 | 2022-08-18 18:40:41 +0530 | [diff] [blame] | 52 | #include <linux/memory-tiers.h> |
Christoph Lameter | b20a350 | 2006-03-22 00:09:12 -0800 | [diff] [blame] | 53 | |
Michal Nazarewicz | 0d1836c | 2010-12-21 17:24:26 -0800 | [diff] [blame] | 54 | #include <asm/tlbflush.h> |
| 55 | |
Mel Gorman | 7b2a2d4 | 2012-10-19 14:07:31 +0100 | [diff] [blame] | 56 | #include <trace/events/migrate.h> |
| 57 | |
Christoph Lameter | b20a350 | 2006-03-22 00:09:12 -0800 | [diff] [blame] | 58 | #include "internal.h" |
| 59 | |
Baolin Wang | cd77558 | 2023-02-15 18:39:37 +0800 | [diff] [blame] | 60 | bool isolate_movable_page(struct page *page, isolate_mode_t mode) |
Minchan Kim | bda807d | 2016-07-26 15:23:05 -0700 | [diff] [blame] | 61 | { |
Vishal Moola (Oracle) | 1997949 | 2023-01-30 13:43:51 -0800 | [diff] [blame] | 62 | struct folio *folio = folio_get_nontail_page(page); |
Matthew Wilcox (Oracle) | 68f2736 | 2022-06-07 15:38:48 -0400 | [diff] [blame] | 63 | const struct movable_operations *mops; |
Minchan Kim | bda807d | 2016-07-26 15:23:05 -0700 | [diff] [blame] | 64 | |
| 65 | /* |
| 66 | * Avoid burning cycles with pages that are yet under __free_pages(), |
| 67 | * or just got freed under us. |
| 68 | * |
| 69 | * In case we 'win' a race for a movable page being freed under us and |
| 70 | * raise its refcount preventing __free_pages() from doing its job |
| 71 | * the put_page() at the end of this block will take care of |
| 72 | * release this page, thus avoiding a nasty leakage. |
| 73 | */ |
Vishal Moola (Oracle) | 1997949 | 2023-01-30 13:43:51 -0800 | [diff] [blame] | 74 | if (!folio) |
Minchan Kim | bda807d | 2016-07-26 15:23:05 -0700 | [diff] [blame] | 75 | goto out; |
| 76 | |
Vishal Moola (Oracle) | 1997949 | 2023-01-30 13:43:51 -0800 | [diff] [blame] | 77 | if (unlikely(folio_test_slab(folio))) |
| 78 | goto out_putfolio; |
Vlastimil Babka | 8b88176 | 2022-11-04 15:57:26 +0100 | [diff] [blame] | 79 | /* Pairs with smp_wmb() in slab freeing, e.g. SLUB's __free_slab() */ |
| 80 | smp_rmb(); |
Minchan Kim | bda807d | 2016-07-26 15:23:05 -0700 | [diff] [blame] | 81 | /* |
Vlastimil Babka | 8b88176 | 2022-11-04 15:57:26 +0100 | [diff] [blame] | 82 | * Check movable flag before taking the page lock because |
| 83 | * we use non-atomic bitops on newly allocated page flags so |
| 84 | * unconditionally grabbing the lock ruins page's owner side. |
Minchan Kim | bda807d | 2016-07-26 15:23:05 -0700 | [diff] [blame] | 85 | */ |
Vishal Moola (Oracle) | 1997949 | 2023-01-30 13:43:51 -0800 | [diff] [blame] | 86 | if (unlikely(!__folio_test_movable(folio))) |
| 87 | goto out_putfolio; |
Vlastimil Babka | 8b88176 | 2022-11-04 15:57:26 +0100 | [diff] [blame] | 88 | /* Pairs with smp_wmb() in slab allocation, e.g. SLUB's alloc_slab_page() */ |
| 89 | smp_rmb(); |
Vishal Moola (Oracle) | 1997949 | 2023-01-30 13:43:51 -0800 | [diff] [blame] | 90 | if (unlikely(folio_test_slab(folio))) |
| 91 | goto out_putfolio; |
Vlastimil Babka | 8b88176 | 2022-11-04 15:57:26 +0100 | [diff] [blame] | 92 | |
Minchan Kim | bda807d | 2016-07-26 15:23:05 -0700 | [diff] [blame] | 93 | /* |
| 94 | * As movable pages are not isolated from LRU lists, concurrent |
| 95 | * compaction threads can race against page migration functions |
| 96 | * as well as race against the releasing a page. |
| 97 | * |
| 98 | * In order to avoid having an already isolated movable page |
| 99 | * being (wrongly) re-isolated while it is under migration, |
| 100 | * or to avoid attempting to isolate pages being released, |
| 101 | * lets be sure we have the page lock |
| 102 | * before proceeding with the movable page isolation steps. |
| 103 | */ |
Vishal Moola (Oracle) | 1997949 | 2023-01-30 13:43:51 -0800 | [diff] [blame] | 104 | if (unlikely(!folio_trylock(folio))) |
| 105 | goto out_putfolio; |
Minchan Kim | bda807d | 2016-07-26 15:23:05 -0700 | [diff] [blame] | 106 | |
Vishal Moola (Oracle) | 1997949 | 2023-01-30 13:43:51 -0800 | [diff] [blame] | 107 | if (!folio_test_movable(folio) || folio_test_isolated(folio)) |
Minchan Kim | bda807d | 2016-07-26 15:23:05 -0700 | [diff] [blame] | 108 | goto out_no_isolated; |
| 109 | |
Vishal Moola (Oracle) | 1997949 | 2023-01-30 13:43:51 -0800 | [diff] [blame] | 110 | mops = folio_movable_ops(folio); |
| 111 | VM_BUG_ON_FOLIO(!mops, folio); |
Minchan Kim | bda807d | 2016-07-26 15:23:05 -0700 | [diff] [blame] | 112 | |
Vishal Moola (Oracle) | 1997949 | 2023-01-30 13:43:51 -0800 | [diff] [blame] | 113 | if (!mops->isolate_page(&folio->page, mode)) |
Minchan Kim | bda807d | 2016-07-26 15:23:05 -0700 | [diff] [blame] | 114 | goto out_no_isolated; |
| 115 | |
| 116 | /* Driver shouldn't use PG_isolated bit of page->flags */ |
Vishal Moola (Oracle) | 1997949 | 2023-01-30 13:43:51 -0800 | [diff] [blame] | 117 | WARN_ON_ONCE(folio_test_isolated(folio)); |
| 118 | folio_set_isolated(folio); |
| 119 | folio_unlock(folio); |
Minchan Kim | bda807d | 2016-07-26 15:23:05 -0700 | [diff] [blame] | 120 | |
Baolin Wang | cd77558 | 2023-02-15 18:39:37 +0800 | [diff] [blame] | 121 | return true; |
Minchan Kim | bda807d | 2016-07-26 15:23:05 -0700 | [diff] [blame] | 122 | |
| 123 | out_no_isolated: |
Vishal Moola (Oracle) | 1997949 | 2023-01-30 13:43:51 -0800 | [diff] [blame] | 124 | folio_unlock(folio); |
| 125 | out_putfolio: |
| 126 | folio_put(folio); |
Minchan Kim | bda807d | 2016-07-26 15:23:05 -0700 | [diff] [blame] | 127 | out: |
Baolin Wang | cd77558 | 2023-02-15 18:39:37 +0800 | [diff] [blame] | 128 | return false; |
Minchan Kim | bda807d | 2016-07-26 15:23:05 -0700 | [diff] [blame] | 129 | } |
| 130 | |
Vishal Moola (Oracle) | 280d724 | 2023-01-30 13:43:52 -0800 | [diff] [blame] | 131 | static void putback_movable_folio(struct folio *folio) |
Minchan Kim | bda807d | 2016-07-26 15:23:05 -0700 | [diff] [blame] | 132 | { |
Vishal Moola (Oracle) | 280d724 | 2023-01-30 13:43:52 -0800 | [diff] [blame] | 133 | const struct movable_operations *mops = folio_movable_ops(folio); |
Minchan Kim | bda807d | 2016-07-26 15:23:05 -0700 | [diff] [blame] | 134 | |
Vishal Moola (Oracle) | 280d724 | 2023-01-30 13:43:52 -0800 | [diff] [blame] | 135 | mops->putback_page(&folio->page); |
| 136 | folio_clear_isolated(folio); |
Minchan Kim | bda807d | 2016-07-26 15:23:05 -0700 | [diff] [blame] | 137 | } |
| 138 | |
Christoph Lameter | b20a350 | 2006-03-22 00:09:12 -0800 | [diff] [blame] | 139 | /* |
Rafael Aquini | 5733c7d | 2012-12-11 16:02:47 -0800 | [diff] [blame] | 140 | * Put previously isolated pages back onto the appropriate lists |
| 141 | * from where they were once taken off for compaction/migration. |
| 142 | * |
Joonsoo Kim | 59c82b7 | 2014-01-21 15:51:17 -0800 | [diff] [blame] | 143 | * This function shall be used whenever the isolated pageset has been |
| 144 | * built from lru, balloon, hugetlbfs page. See isolate_migratepages_range() |
Miaohe Lin | 7ce82f4 | 2022-05-30 19:30:15 +0800 | [diff] [blame] | 145 | * and isolate_hugetlb(). |
Rafael Aquini | 5733c7d | 2012-12-11 16:02:47 -0800 | [diff] [blame] | 146 | */ |
| 147 | void putback_movable_pages(struct list_head *l) |
| 148 | { |
Vishal Moola (Oracle) | 280d724 | 2023-01-30 13:43:52 -0800 | [diff] [blame] | 149 | struct folio *folio; |
| 150 | struct folio *folio2; |
Rafael Aquini | 5733c7d | 2012-12-11 16:02:47 -0800 | [diff] [blame] | 151 | |
Vishal Moola (Oracle) | 280d724 | 2023-01-30 13:43:52 -0800 | [diff] [blame] | 152 | list_for_each_entry_safe(folio, folio2, l, lru) { |
| 153 | if (unlikely(folio_test_hugetlb(folio))) { |
| 154 | folio_putback_active_hugetlb(folio); |
Naoya Horiguchi | 31caf66 | 2013-09-11 14:21:59 -0700 | [diff] [blame] | 155 | continue; |
| 156 | } |
Vishal Moola (Oracle) | 280d724 | 2023-01-30 13:43:52 -0800 | [diff] [blame] | 157 | list_del(&folio->lru); |
Minchan Kim | bda807d | 2016-07-26 15:23:05 -0700 | [diff] [blame] | 158 | /* |
Vishal Moola (Oracle) | 280d724 | 2023-01-30 13:43:52 -0800 | [diff] [blame] | 159 | * We isolated non-lru movable folio so here we can use |
| 160 | * __PageMovable because LRU folio's mapping cannot have |
Minchan Kim | bda807d | 2016-07-26 15:23:05 -0700 | [diff] [blame] | 161 | * PAGE_MAPPING_MOVABLE. |
| 162 | */ |
Vishal Moola (Oracle) | 280d724 | 2023-01-30 13:43:52 -0800 | [diff] [blame] | 163 | if (unlikely(__folio_test_movable(folio))) { |
| 164 | VM_BUG_ON_FOLIO(!folio_test_isolated(folio), folio); |
| 165 | folio_lock(folio); |
| 166 | if (folio_test_movable(folio)) |
| 167 | putback_movable_folio(folio); |
Minchan Kim | bda807d | 2016-07-26 15:23:05 -0700 | [diff] [blame] | 168 | else |
Vishal Moola (Oracle) | 280d724 | 2023-01-30 13:43:52 -0800 | [diff] [blame] | 169 | folio_clear_isolated(folio); |
| 170 | folio_unlock(folio); |
| 171 | folio_put(folio); |
Minchan Kim | bda807d | 2016-07-26 15:23:05 -0700 | [diff] [blame] | 172 | } else { |
Vishal Moola (Oracle) | 280d724 | 2023-01-30 13:43:52 -0800 | [diff] [blame] | 173 | node_stat_mod_folio(folio, NR_ISOLATED_ANON + |
| 174 | folio_is_file_lru(folio), -folio_nr_pages(folio)); |
| 175 | folio_putback_lru(folio); |
Minchan Kim | bda807d | 2016-07-26 15:23:05 -0700 | [diff] [blame] | 176 | } |
Christoph Lameter | b20a350 | 2006-03-22 00:09:12 -0800 | [diff] [blame] | 177 | } |
Christoph Lameter | b20a350 | 2006-03-22 00:09:12 -0800 | [diff] [blame] | 178 | } |
| 179 | |
Christoph Lameter | 0697212 | 2006-06-23 02:03:35 -0700 | [diff] [blame] | 180 | /* |
| 181 | * Restore a potential migration pte to a working pte entry |
| 182 | */ |
Matthew Wilcox (Oracle) | 2f031c6 | 2022-01-29 16:06:53 -0500 | [diff] [blame] | 183 | static bool remove_migration_pte(struct folio *folio, |
| 184 | struct vm_area_struct *vma, unsigned long addr, void *old) |
Christoph Lameter | 0697212 | 2006-06-23 02:03:35 -0700 | [diff] [blame] | 185 | { |
Matthew Wilcox (Oracle) | 4eecb8b | 2022-01-28 23:32:59 -0500 | [diff] [blame] | 186 | DEFINE_FOLIO_VMA_WALK(pvmw, old, vma, addr, PVMW_SYNC | PVMW_MIGRATION); |
Christoph Lameter | 0697212 | 2006-06-23 02:03:35 -0700 | [diff] [blame] | 187 | |
Kirill A. Shutemov | 3fe8796 | 2017-02-24 14:58:16 -0800 | [diff] [blame] | 188 | while (page_vma_mapped_walk(&pvmw)) { |
David Hildenbrand | 6c28760 | 2022-05-09 18:20:44 -0700 | [diff] [blame] | 189 | rmap_t rmap_flags = RMAP_NONE; |
Ryan Roberts | c33c794 | 2023-06-12 16:15:45 +0100 | [diff] [blame] | 190 | pte_t old_pte; |
Matthew Wilcox (Oracle) | 4eecb8b | 2022-01-28 23:32:59 -0500 | [diff] [blame] | 191 | pte_t pte; |
| 192 | swp_entry_t entry; |
| 193 | struct page *new; |
| 194 | unsigned long idx = 0; |
| 195 | |
| 196 | /* pgoff is invalid for ksm pages, but they are never large */ |
| 197 | if (folio_test_large(folio) && !folio_test_hugetlb(folio)) |
| 198 | idx = linear_page_index(vma, pvmw.address) - pvmw.pgoff; |
| 199 | new = folio_page(folio, idx); |
Christoph Lameter | 0697212 | 2006-06-23 02:03:35 -0700 | [diff] [blame] | 200 | |
Zi Yan | 616b837 | 2017-09-08 16:10:57 -0700 | [diff] [blame] | 201 | #ifdef CONFIG_ARCH_ENABLE_THP_MIGRATION |
| 202 | /* PMD-mapped THP migration entry */ |
| 203 | if (!pvmw.pte) { |
Matthew Wilcox (Oracle) | 4eecb8b | 2022-01-28 23:32:59 -0500 | [diff] [blame] | 204 | VM_BUG_ON_FOLIO(folio_test_hugetlb(folio) || |
| 205 | !folio_test_pmd_mappable(folio), folio); |
Zi Yan | 616b837 | 2017-09-08 16:10:57 -0700 | [diff] [blame] | 206 | remove_migration_pmd(&pvmw, new); |
| 207 | continue; |
| 208 | } |
| 209 | #endif |
| 210 | |
Matthew Wilcox (Oracle) | 4eecb8b | 2022-01-28 23:32:59 -0500 | [diff] [blame] | 211 | folio_get(folio); |
Peter Xu | 2e34687 | 2022-08-11 12:13:29 -0400 | [diff] [blame] | 212 | pte = mk_pte(new, READ_ONCE(vma->vm_page_prot)); |
Ryan Roberts | c33c794 | 2023-06-12 16:15:45 +0100 | [diff] [blame] | 213 | old_pte = ptep_get(pvmw.pte); |
| 214 | if (pte_swp_soft_dirty(old_pte)) |
Kirill A. Shutemov | 3fe8796 | 2017-02-24 14:58:16 -0800 | [diff] [blame] | 215 | pte = pte_mksoft_dirty(pte); |
Christoph Lameter | 0697212 | 2006-06-23 02:03:35 -0700 | [diff] [blame] | 216 | |
Ryan Roberts | c33c794 | 2023-06-12 16:15:45 +0100 | [diff] [blame] | 217 | entry = pte_to_swp_entry(old_pte); |
Peter Xu | 2e34687 | 2022-08-11 12:13:29 -0400 | [diff] [blame] | 218 | if (!is_migration_entry_young(entry)) |
| 219 | pte = pte_mkold(pte); |
| 220 | if (folio_test_dirty(folio) && is_migration_entry_dirty(entry)) |
| 221 | pte = pte_mkdirty(pte); |
Alistair Popple | 4dd845b | 2021-06-30 18:54:09 -0700 | [diff] [blame] | 222 | if (is_writable_migration_entry(entry)) |
David Hildenbrand | f3ebdf0 | 2023-04-18 16:21:13 +0200 | [diff] [blame] | 223 | pte = pte_mkwrite(pte); |
Ryan Roberts | c33c794 | 2023-06-12 16:15:45 +0100 | [diff] [blame] | 224 | else if (pte_swp_uffd_wp(old_pte)) |
Peter Xu | f45ec5f | 2020-04-06 20:06:01 -0700 | [diff] [blame] | 225 | pte = pte_mkuffd_wp(pte); |
Mel Gorman | d3cb8bf | 2014-10-02 19:47:41 +0100 | [diff] [blame] | 226 | |
David Hildenbrand | 6c28760 | 2022-05-09 18:20:44 -0700 | [diff] [blame] | 227 | if (folio_test_anon(folio) && !is_readable_migration_entry(entry)) |
| 228 | rmap_flags |= RMAP_EXCLUSIVE; |
| 229 | |
Ralph Campbell | 6128763 | 2020-09-04 16:36:04 -0700 | [diff] [blame] | 230 | if (unlikely(is_device_private_page(new))) { |
Alistair Popple | 4dd845b | 2021-06-30 18:54:09 -0700 | [diff] [blame] | 231 | if (pte_write(pte)) |
| 232 | entry = make_writable_device_private_entry( |
| 233 | page_to_pfn(new)); |
| 234 | else |
| 235 | entry = make_readable_device_private_entry( |
| 236 | page_to_pfn(new)); |
Ralph Campbell | 6128763 | 2020-09-04 16:36:04 -0700 | [diff] [blame] | 237 | pte = swp_entry_to_pte(entry); |
Ryan Roberts | c33c794 | 2023-06-12 16:15:45 +0100 | [diff] [blame] | 238 | if (pte_swp_soft_dirty(old_pte)) |
Ralph Campbell | 3d321bf8 | 2020-09-04 16:36:07 -0700 | [diff] [blame] | 239 | pte = pte_swp_mksoft_dirty(pte); |
Ryan Roberts | c33c794 | 2023-06-12 16:15:45 +0100 | [diff] [blame] | 240 | if (pte_swp_uffd_wp(old_pte)) |
Ralph Campbell | 6128763 | 2020-09-04 16:36:04 -0700 | [diff] [blame] | 241 | pte = pte_swp_mkuffd_wp(pte); |
Lars Persson | d2b2c6dd | 2019-03-28 20:44:28 -0700 | [diff] [blame] | 242 | } |
Jérôme Glisse | a5430dd | 2017-09-08 16:12:17 -0700 | [diff] [blame] | 243 | |
Andi Kleen | 3ef8fd7 | 2010-10-11 16:03:21 +0200 | [diff] [blame] | 244 | #ifdef CONFIG_HUGETLB_PAGE |
Matthew Wilcox (Oracle) | 4eecb8b | 2022-01-28 23:32:59 -0500 | [diff] [blame] | 245 | if (folio_test_hugetlb(folio)) { |
Christophe Leroy | 79c1c59 | 2021-06-30 18:48:00 -0700 | [diff] [blame] | 246 | unsigned int shift = huge_page_shift(hstate_vma(vma)); |
| 247 | |
Christophe Leroy | 79c1c59 | 2021-06-30 18:48:00 -0700 | [diff] [blame] | 248 | pte = arch_make_huge_pte(pte, shift, vma->vm_flags); |
Matthew Wilcox (Oracle) | 4eecb8b | 2022-01-28 23:32:59 -0500 | [diff] [blame] | 249 | if (folio_test_anon(folio)) |
David Hildenbrand | 28c5209 | 2022-05-09 18:20:43 -0700 | [diff] [blame] | 250 | hugepage_add_anon_rmap(new, vma, pvmw.address, |
David Hildenbrand | 6c28760 | 2022-05-09 18:20:44 -0700 | [diff] [blame] | 251 | rmap_flags); |
Kirill A. Shutemov | 3fe8796 | 2017-02-24 14:58:16 -0800 | [diff] [blame] | 252 | else |
David Hildenbrand | fb3d824 | 2022-05-09 18:20:43 -0700 | [diff] [blame] | 253 | page_dup_file_rmap(new, true); |
Pasha Tatashin | 1eba86c | 2022-01-14 14:06:29 -0800 | [diff] [blame] | 254 | set_huge_pte_at(vma->vm_mm, pvmw.address, pvmw.pte, pte); |
Aneesh Kumar K.V | 383321a | 2017-07-06 15:38:41 -0700 | [diff] [blame] | 255 | } else |
| 256 | #endif |
| 257 | { |
Matthew Wilcox (Oracle) | 4eecb8b | 2022-01-28 23:32:59 -0500 | [diff] [blame] | 258 | if (folio_test_anon(folio)) |
David Hildenbrand | f1e2db1 | 2022-05-09 18:20:43 -0700 | [diff] [blame] | 259 | page_add_anon_rmap(new, vma, pvmw.address, |
David Hildenbrand | 6c28760 | 2022-05-09 18:20:44 -0700 | [diff] [blame] | 260 | rmap_flags); |
Aneesh Kumar K.V | 383321a | 2017-07-06 15:38:41 -0700 | [diff] [blame] | 261 | else |
Hugh Dickins | cea86fe | 2022-02-14 18:26:39 -0800 | [diff] [blame] | 262 | page_add_file_rmap(new, vma, false); |
Pasha Tatashin | 1eba86c | 2022-01-14 14:06:29 -0800 | [diff] [blame] | 263 | set_pte_at(vma->vm_mm, pvmw.address, pvmw.pte, pte); |
Aneesh Kumar K.V | 383321a | 2017-07-06 15:38:41 -0700 | [diff] [blame] | 264 | } |
Hugh Dickins | b743550 | 2022-02-14 18:38:47 -0800 | [diff] [blame] | 265 | if (vma->vm_flags & VM_LOCKED) |
Lorenzo Stoakes | 96f97c4 | 2023-01-12 12:39:31 +0000 | [diff] [blame] | 266 | mlock_drain_local(); |
Kirill A. Shutemov | e125fe4 | 2018-10-05 15:51:41 -0700 | [diff] [blame] | 267 | |
Anshuman Khandual | 4cc79b3 | 2022-03-24 18:10:01 -0700 | [diff] [blame] | 268 | trace_remove_migration_pte(pvmw.address, pte_val(pte), |
| 269 | compound_order(new)); |
| 270 | |
Kirill A. Shutemov | 3fe8796 | 2017-02-24 14:58:16 -0800 | [diff] [blame] | 271 | /* No need to invalidate - it was non-present before */ |
| 272 | update_mmu_cache(vma, pvmw.address, pvmw.pte); |
| 273 | } |
| 274 | |
Minchan Kim | e4b8222 | 2017-05-03 14:54:27 -0700 | [diff] [blame] | 275 | return true; |
Christoph Lameter | 0697212 | 2006-06-23 02:03:35 -0700 | [diff] [blame] | 276 | } |
| 277 | |
| 278 | /* |
Christoph Lameter | 04e62a2 | 2006-06-23 02:03:38 -0700 | [diff] [blame] | 279 | * Get rid of all migration entries and replace them by |
| 280 | * references to the indicated page. |
| 281 | */ |
Matthew Wilcox (Oracle) | 4eecb8b | 2022-01-28 23:32:59 -0500 | [diff] [blame] | 282 | void remove_migration_ptes(struct folio *src, struct folio *dst, bool locked) |
Christoph Lameter | 04e62a2 | 2006-06-23 02:03:38 -0700 | [diff] [blame] | 283 | { |
Joonsoo Kim | 051ac83 | 2014-01-21 15:49:48 -0800 | [diff] [blame] | 284 | struct rmap_walk_control rwc = { |
| 285 | .rmap_one = remove_migration_pte, |
Matthew Wilcox (Oracle) | 4eecb8b | 2022-01-28 23:32:59 -0500 | [diff] [blame] | 286 | .arg = src, |
Joonsoo Kim | 051ac83 | 2014-01-21 15:49:48 -0800 | [diff] [blame] | 287 | }; |
| 288 | |
Kirill A. Shutemov | e388466 | 2016-03-17 14:20:07 -0700 | [diff] [blame] | 289 | if (locked) |
Matthew Wilcox (Oracle) | 2f031c6 | 2022-01-29 16:06:53 -0500 | [diff] [blame] | 290 | rmap_walk_locked(dst, &rwc); |
Kirill A. Shutemov | e388466 | 2016-03-17 14:20:07 -0700 | [diff] [blame] | 291 | else |
Matthew Wilcox (Oracle) | 2f031c6 | 2022-01-29 16:06:53 -0500 | [diff] [blame] | 292 | rmap_walk(dst, &rwc); |
Christoph Lameter | 04e62a2 | 2006-06-23 02:03:38 -0700 | [diff] [blame] | 293 | } |
| 294 | |
| 295 | /* |
Christoph Lameter | 0697212 | 2006-06-23 02:03:35 -0700 | [diff] [blame] | 296 | * Something used the pte of a page under migration. We need to |
| 297 | * get to the page and wait until migration is finished. |
| 298 | * When we return from this function the fault will be retried. |
Christoph Lameter | 0697212 | 2006-06-23 02:03:35 -0700 | [diff] [blame] | 299 | */ |
Hugh Dickins | 0cb8fd4 | 2023-06-08 18:08:20 -0700 | [diff] [blame] | 300 | void migration_entry_wait(struct mm_struct *mm, pmd_t *pmd, |
| 301 | unsigned long address) |
Christoph Lameter | 0697212 | 2006-06-23 02:03:35 -0700 | [diff] [blame] | 302 | { |
Hugh Dickins | 0cb8fd4 | 2023-06-08 18:08:20 -0700 | [diff] [blame] | 303 | spinlock_t *ptl; |
| 304 | pte_t *ptep; |
Naoya Horiguchi | 30dad30 | 2013-06-12 14:05:04 -0700 | [diff] [blame] | 305 | pte_t pte; |
Christoph Lameter | 0697212 | 2006-06-23 02:03:35 -0700 | [diff] [blame] | 306 | swp_entry_t entry; |
Christoph Lameter | 0697212 | 2006-06-23 02:03:35 -0700 | [diff] [blame] | 307 | |
Hugh Dickins | 0cb8fd4 | 2023-06-08 18:08:20 -0700 | [diff] [blame] | 308 | ptep = pte_offset_map_lock(mm, pmd, address, &ptl); |
Hugh Dickins | 04dee9e | 2023-06-08 18:29:22 -0700 | [diff] [blame] | 309 | if (!ptep) |
| 310 | return; |
| 311 | |
Ryan Roberts | c33c794 | 2023-06-12 16:15:45 +0100 | [diff] [blame] | 312 | pte = ptep_get(ptep); |
Hugh Dickins | 0cb8fd4 | 2023-06-08 18:08:20 -0700 | [diff] [blame] | 313 | pte_unmap(ptep); |
| 314 | |
Christoph Lameter | 0697212 | 2006-06-23 02:03:35 -0700 | [diff] [blame] | 315 | if (!is_swap_pte(pte)) |
| 316 | goto out; |
| 317 | |
| 318 | entry = pte_to_swp_entry(pte); |
| 319 | if (!is_migration_entry(entry)) |
| 320 | goto out; |
| 321 | |
Hugh Dickins | 0cb8fd4 | 2023-06-08 18:08:20 -0700 | [diff] [blame] | 322 | migration_entry_wait_on_locked(entry, ptl); |
Christoph Lameter | 0697212 | 2006-06-23 02:03:35 -0700 | [diff] [blame] | 323 | return; |
| 324 | out: |
Hugh Dickins | 0cb8fd4 | 2023-06-08 18:08:20 -0700 | [diff] [blame] | 325 | spin_unlock(ptl); |
Naoya Horiguchi | 30dad30 | 2013-06-12 14:05:04 -0700 | [diff] [blame] | 326 | } |
| 327 | |
Miaohe Lin | ad1ac59 | 2022-05-30 19:30:16 +0800 | [diff] [blame] | 328 | #ifdef CONFIG_HUGETLB_PAGE |
Peter Xu | fcd4854 | 2022-12-16 10:50:55 -0500 | [diff] [blame] | 329 | /* |
| 330 | * The vma read lock must be held upon entry. Holding that lock prevents either |
| 331 | * the pte or the ptl from being freed. |
| 332 | * |
| 333 | * This function will release the vma lock before returning. |
| 334 | */ |
Hugh Dickins | 0cb8fd4 | 2023-06-08 18:08:20 -0700 | [diff] [blame] | 335 | void migration_entry_wait_huge(struct vm_area_struct *vma, pte_t *ptep) |
Naoya Horiguchi | 30dad30 | 2013-06-12 14:05:04 -0700 | [diff] [blame] | 336 | { |
Hugh Dickins | 0cb8fd4 | 2023-06-08 18:08:20 -0700 | [diff] [blame] | 337 | spinlock_t *ptl = huge_pte_lockptr(hstate_vma(vma), vma->vm_mm, ptep); |
Miaohe Lin | ad1ac59 | 2022-05-30 19:30:16 +0800 | [diff] [blame] | 338 | pte_t pte; |
| 339 | |
Peter Xu | fcd4854 | 2022-12-16 10:50:55 -0500 | [diff] [blame] | 340 | hugetlb_vma_assert_locked(vma); |
Miaohe Lin | ad1ac59 | 2022-05-30 19:30:16 +0800 | [diff] [blame] | 341 | spin_lock(ptl); |
| 342 | pte = huge_ptep_get(ptep); |
| 343 | |
Peter Xu | fcd4854 | 2022-12-16 10:50:55 -0500 | [diff] [blame] | 344 | if (unlikely(!is_hugetlb_entry_migration(pte))) { |
Miaohe Lin | ad1ac59 | 2022-05-30 19:30:16 +0800 | [diff] [blame] | 345 | spin_unlock(ptl); |
Peter Xu | fcd4854 | 2022-12-16 10:50:55 -0500 | [diff] [blame] | 346 | hugetlb_vma_unlock_read(vma); |
| 347 | } else { |
| 348 | /* |
| 349 | * If migration entry existed, safe to release vma lock |
| 350 | * here because the pgtable page won't be freed without the |
| 351 | * pgtable lock released. See comment right above pgtable |
| 352 | * lock release in migration_entry_wait_on_locked(). |
| 353 | */ |
| 354 | hugetlb_vma_unlock_read(vma); |
Hugh Dickins | 0cb8fd4 | 2023-06-08 18:08:20 -0700 | [diff] [blame] | 355 | migration_entry_wait_on_locked(pte_to_swp_entry(pte), ptl); |
Peter Xu | fcd4854 | 2022-12-16 10:50:55 -0500 | [diff] [blame] | 356 | } |
Naoya Horiguchi | 30dad30 | 2013-06-12 14:05:04 -0700 | [diff] [blame] | 357 | } |
Miaohe Lin | ad1ac59 | 2022-05-30 19:30:16 +0800 | [diff] [blame] | 358 | #endif |
| 359 | |
Zi Yan | 616b837 | 2017-09-08 16:10:57 -0700 | [diff] [blame] | 360 | #ifdef CONFIG_ARCH_ENABLE_THP_MIGRATION |
| 361 | void pmd_migration_entry_wait(struct mm_struct *mm, pmd_t *pmd) |
| 362 | { |
| 363 | spinlock_t *ptl; |
Zi Yan | 616b837 | 2017-09-08 16:10:57 -0700 | [diff] [blame] | 364 | |
| 365 | ptl = pmd_lock(mm, pmd); |
| 366 | if (!is_pmd_migration_entry(*pmd)) |
| 367 | goto unlock; |
Hugh Dickins | 0cb8fd4 | 2023-06-08 18:08:20 -0700 | [diff] [blame] | 368 | migration_entry_wait_on_locked(pmd_to_swp_entry(*pmd), ptl); |
Zi Yan | 616b837 | 2017-09-08 16:10:57 -0700 | [diff] [blame] | 369 | return; |
| 370 | unlock: |
| 371 | spin_unlock(ptl); |
| 372 | } |
| 373 | #endif |
| 374 | |
Matthew Wilcox (Oracle) | 108ca83 | 2022-06-06 16:25:10 -0400 | [diff] [blame] | 375 | static int folio_expected_refs(struct address_space *mapping, |
| 376 | struct folio *folio) |
Jan Kara | 0b3901b | 2018-12-28 00:39:01 -0800 | [diff] [blame] | 377 | { |
Matthew Wilcox (Oracle) | 108ca83 | 2022-06-06 16:25:10 -0400 | [diff] [blame] | 378 | int refs = 1; |
| 379 | if (!mapping) |
| 380 | return refs; |
Jan Kara | 0b3901b | 2018-12-28 00:39:01 -0800 | [diff] [blame] | 381 | |
Matthew Wilcox (Oracle) | 108ca83 | 2022-06-06 16:25:10 -0400 | [diff] [blame] | 382 | refs += folio_nr_pages(folio); |
| 383 | if (folio_test_private(folio)) |
| 384 | refs++; |
| 385 | |
| 386 | return refs; |
Jan Kara | 0b3901b | 2018-12-28 00:39:01 -0800 | [diff] [blame] | 387 | } |
| 388 | |
Christoph Lameter | b20a350 | 2006-03-22 00:09:12 -0800 | [diff] [blame] | 389 | /* |
Christoph Lameter | c3fcf8a | 2006-06-23 02:03:32 -0700 | [diff] [blame] | 390 | * Replace the page in the mapping. |
Christoph Lameter | 5b5c712 | 2006-06-23 02:03:29 -0700 | [diff] [blame] | 391 | * |
| 392 | * The number of remaining references must be: |
| 393 | * 1 for anonymous pages without a mapping |
| 394 | * 2 for pages with a mapping |
David Howells | 266cf65 | 2009-04-03 16:42:36 +0100 | [diff] [blame] | 395 | * 3 for pages with a mapping and PagePrivate/PagePrivate2 set. |
Christoph Lameter | b20a350 | 2006-03-22 00:09:12 -0800 | [diff] [blame] | 396 | */ |
Matthew Wilcox (Oracle) | 3417013 | 2021-05-07 07:28:40 -0400 | [diff] [blame] | 397 | int folio_migrate_mapping(struct address_space *mapping, |
| 398 | struct folio *newfolio, struct folio *folio, int extra_count) |
Christoph Lameter | b20a350 | 2006-03-22 00:09:12 -0800 | [diff] [blame] | 399 | { |
Matthew Wilcox (Oracle) | 3417013 | 2021-05-07 07:28:40 -0400 | [diff] [blame] | 400 | XA_STATE(xas, &mapping->i_pages, folio_index(folio)); |
Hugh Dickins | 42cb14b | 2015-11-05 18:50:05 -0800 | [diff] [blame] | 401 | struct zone *oldzone, *newzone; |
| 402 | int dirty; |
Matthew Wilcox (Oracle) | 108ca83 | 2022-06-06 16:25:10 -0400 | [diff] [blame] | 403 | int expected_count = folio_expected_refs(mapping, folio) + extra_count; |
Matthew Wilcox (Oracle) | 3417013 | 2021-05-07 07:28:40 -0400 | [diff] [blame] | 404 | long nr = folio_nr_pages(folio); |
Jérôme Glisse | 8763cb4 | 2017-09-08 16:12:09 -0700 | [diff] [blame] | 405 | |
Christoph Lameter | 6c5240a | 2006-06-23 02:03:37 -0700 | [diff] [blame] | 406 | if (!mapping) { |
Christoph Lameter | 0e8c7d0 | 2007-04-23 14:41:09 -0700 | [diff] [blame] | 407 | /* Anonymous page without mapping */ |
Matthew Wilcox (Oracle) | 3417013 | 2021-05-07 07:28:40 -0400 | [diff] [blame] | 408 | if (folio_ref_count(folio) != expected_count) |
Christoph Lameter | 6c5240a | 2006-06-23 02:03:37 -0700 | [diff] [blame] | 409 | return -EAGAIN; |
Hugh Dickins | cf4b769 | 2015-11-05 18:50:02 -0800 | [diff] [blame] | 410 | |
| 411 | /* No turning back from here */ |
Matthew Wilcox (Oracle) | 3417013 | 2021-05-07 07:28:40 -0400 | [diff] [blame] | 412 | newfolio->index = folio->index; |
| 413 | newfolio->mapping = folio->mapping; |
| 414 | if (folio_test_swapbacked(folio)) |
| 415 | __folio_set_swapbacked(newfolio); |
Hugh Dickins | cf4b769 | 2015-11-05 18:50:02 -0800 | [diff] [blame] | 416 | |
Rafael Aquini | 78bd520 | 2012-12-11 16:02:31 -0800 | [diff] [blame] | 417 | return MIGRATEPAGE_SUCCESS; |
Christoph Lameter | 6c5240a | 2006-06-23 02:03:37 -0700 | [diff] [blame] | 418 | } |
| 419 | |
Matthew Wilcox (Oracle) | 3417013 | 2021-05-07 07:28:40 -0400 | [diff] [blame] | 420 | oldzone = folio_zone(folio); |
| 421 | newzone = folio_zone(newfolio); |
Hugh Dickins | 42cb14b | 2015-11-05 18:50:05 -0800 | [diff] [blame] | 422 | |
Matthew Wilcox | 89eb946 | 2017-12-04 04:35:16 -0500 | [diff] [blame] | 423 | xas_lock_irq(&xas); |
Matthew Wilcox (Oracle) | 3417013 | 2021-05-07 07:28:40 -0400 | [diff] [blame] | 424 | if (!folio_ref_freeze(folio, expected_count)) { |
Matthew Wilcox | 89eb946 | 2017-12-04 04:35:16 -0500 | [diff] [blame] | 425 | xas_unlock_irq(&xas); |
Nick Piggin | e286781 | 2008-07-25 19:45:30 -0700 | [diff] [blame] | 426 | return -EAGAIN; |
| 427 | } |
| 428 | |
Christoph Lameter | b20a350 | 2006-03-22 00:09:12 -0800 | [diff] [blame] | 429 | /* |
Matthew Wilcox (Oracle) | 3417013 | 2021-05-07 07:28:40 -0400 | [diff] [blame] | 430 | * Now we know that no one else is looking at the folio: |
Hugh Dickins | cf4b769 | 2015-11-05 18:50:02 -0800 | [diff] [blame] | 431 | * no turning back from here. |
Christoph Lameter | b20a350 | 2006-03-22 00:09:12 -0800 | [diff] [blame] | 432 | */ |
Matthew Wilcox (Oracle) | 3417013 | 2021-05-07 07:28:40 -0400 | [diff] [blame] | 433 | newfolio->index = folio->index; |
| 434 | newfolio->mapping = folio->mapping; |
| 435 | folio_ref_add(newfolio, nr); /* add cache reference */ |
| 436 | if (folio_test_swapbacked(folio)) { |
| 437 | __folio_set_swapbacked(newfolio); |
| 438 | if (folio_test_swapcache(folio)) { |
| 439 | folio_set_swapcache(newfolio); |
| 440 | newfolio->private = folio_get_private(folio); |
Nicholas Piggin | 6326fec | 2016-12-25 13:00:29 +1000 | [diff] [blame] | 441 | } |
| 442 | } else { |
Matthew Wilcox (Oracle) | 3417013 | 2021-05-07 07:28:40 -0400 | [diff] [blame] | 443 | VM_BUG_ON_FOLIO(folio_test_swapcache(folio), folio); |
Christoph Lameter | b20a350 | 2006-03-22 00:09:12 -0800 | [diff] [blame] | 444 | } |
| 445 | |
Hugh Dickins | 42cb14b | 2015-11-05 18:50:05 -0800 | [diff] [blame] | 446 | /* Move dirty while page refs frozen and newpage not yet exposed */ |
Matthew Wilcox (Oracle) | 3417013 | 2021-05-07 07:28:40 -0400 | [diff] [blame] | 447 | dirty = folio_test_dirty(folio); |
Hugh Dickins | 42cb14b | 2015-11-05 18:50:05 -0800 | [diff] [blame] | 448 | if (dirty) { |
Matthew Wilcox (Oracle) | 3417013 | 2021-05-07 07:28:40 -0400 | [diff] [blame] | 449 | folio_clear_dirty(folio); |
| 450 | folio_set_dirty(newfolio); |
Hugh Dickins | 42cb14b | 2015-11-05 18:50:05 -0800 | [diff] [blame] | 451 | } |
| 452 | |
Matthew Wilcox (Oracle) | 3417013 | 2021-05-07 07:28:40 -0400 | [diff] [blame] | 453 | xas_store(&xas, newfolio); |
Nick Piggin | 7cf9c2c | 2006-12-06 20:33:44 -0800 | [diff] [blame] | 454 | |
| 455 | /* |
Jacobo Giralt | 937a94c | 2012-01-10 15:07:11 -0800 | [diff] [blame] | 456 | * Drop cache reference from old page by unfreezing |
| 457 | * to one less reference. |
Nick Piggin | 7cf9c2c | 2006-12-06 20:33:44 -0800 | [diff] [blame] | 458 | * We know this isn't the last reference. |
| 459 | */ |
Matthew Wilcox (Oracle) | 3417013 | 2021-05-07 07:28:40 -0400 | [diff] [blame] | 460 | folio_ref_unfreeze(folio, expected_count - nr); |
Nick Piggin | 7cf9c2c | 2006-12-06 20:33:44 -0800 | [diff] [blame] | 461 | |
Matthew Wilcox | 89eb946 | 2017-12-04 04:35:16 -0500 | [diff] [blame] | 462 | xas_unlock(&xas); |
Hugh Dickins | 42cb14b | 2015-11-05 18:50:05 -0800 | [diff] [blame] | 463 | /* Leave irq disabled to prevent preemption while updating stats */ |
| 464 | |
Christoph Lameter | 0e8c7d0 | 2007-04-23 14:41:09 -0700 | [diff] [blame] | 465 | /* |
| 466 | * If moved to a different zone then also account |
| 467 | * the page for that zone. Other VM counters will be |
| 468 | * taken care of when we establish references to the |
| 469 | * new page and drop references to the old page. |
| 470 | * |
| 471 | * Note that anonymous pages are accounted for |
Mel Gorman | 4b9d0fa | 2016-07-28 15:46:17 -0700 | [diff] [blame] | 472 | * via NR_FILE_PAGES and NR_ANON_MAPPED if they |
Christoph Lameter | 0e8c7d0 | 2007-04-23 14:41:09 -0700 | [diff] [blame] | 473 | * are mapped to swap space. |
| 474 | */ |
Hugh Dickins | 42cb14b | 2015-11-05 18:50:05 -0800 | [diff] [blame] | 475 | if (newzone != oldzone) { |
Johannes Weiner | 0d1c207 | 2020-06-03 16:01:54 -0700 | [diff] [blame] | 476 | struct lruvec *old_lruvec, *new_lruvec; |
| 477 | struct mem_cgroup *memcg; |
| 478 | |
Matthew Wilcox (Oracle) | 3417013 | 2021-05-07 07:28:40 -0400 | [diff] [blame] | 479 | memcg = folio_memcg(folio); |
Johannes Weiner | 0d1c207 | 2020-06-03 16:01:54 -0700 | [diff] [blame] | 480 | old_lruvec = mem_cgroup_lruvec(memcg, oldzone->zone_pgdat); |
| 481 | new_lruvec = mem_cgroup_lruvec(memcg, newzone->zone_pgdat); |
| 482 | |
Shakeel Butt | 5c447d2 | 2021-01-23 21:01:15 -0800 | [diff] [blame] | 483 | __mod_lruvec_state(old_lruvec, NR_FILE_PAGES, -nr); |
| 484 | __mod_lruvec_state(new_lruvec, NR_FILE_PAGES, nr); |
Matthew Wilcox (Oracle) | 3417013 | 2021-05-07 07:28:40 -0400 | [diff] [blame] | 485 | if (folio_test_swapbacked(folio) && !folio_test_swapcache(folio)) { |
Shakeel Butt | 5c447d2 | 2021-01-23 21:01:15 -0800 | [diff] [blame] | 486 | __mod_lruvec_state(old_lruvec, NR_SHMEM, -nr); |
| 487 | __mod_lruvec_state(new_lruvec, NR_SHMEM, nr); |
Jan Glauber | 0b52c42 | 2023-06-19 12:33:51 +0200 | [diff] [blame] | 488 | |
| 489 | if (folio_test_pmd_mappable(folio)) { |
| 490 | __mod_lruvec_state(old_lruvec, NR_SHMEM_THPS, -nr); |
| 491 | __mod_lruvec_state(new_lruvec, NR_SHMEM_THPS, nr); |
| 492 | } |
Hugh Dickins | 42cb14b | 2015-11-05 18:50:05 -0800 | [diff] [blame] | 493 | } |
Shakeel Butt | b603894 | 2021-02-24 12:03:55 -0800 | [diff] [blame] | 494 | #ifdef CONFIG_SWAP |
Matthew Wilcox (Oracle) | 3417013 | 2021-05-07 07:28:40 -0400 | [diff] [blame] | 495 | if (folio_test_swapcache(folio)) { |
Shakeel Butt | b603894 | 2021-02-24 12:03:55 -0800 | [diff] [blame] | 496 | __mod_lruvec_state(old_lruvec, NR_SWAPCACHE, -nr); |
| 497 | __mod_lruvec_state(new_lruvec, NR_SWAPCACHE, nr); |
| 498 | } |
| 499 | #endif |
Christoph Hellwig | f56753a | 2020-09-24 08:51:40 +0200 | [diff] [blame] | 500 | if (dirty && mapping_can_writeback(mapping)) { |
Shakeel Butt | 5c447d2 | 2021-01-23 21:01:15 -0800 | [diff] [blame] | 501 | __mod_lruvec_state(old_lruvec, NR_FILE_DIRTY, -nr); |
| 502 | __mod_zone_page_state(oldzone, NR_ZONE_WRITE_PENDING, -nr); |
| 503 | __mod_lruvec_state(new_lruvec, NR_FILE_DIRTY, nr); |
| 504 | __mod_zone_page_state(newzone, NR_ZONE_WRITE_PENDING, nr); |
Hugh Dickins | 42cb14b | 2015-11-05 18:50:05 -0800 | [diff] [blame] | 505 | } |
KOSAKI Motohiro | 4b02108 | 2009-09-21 17:01:33 -0700 | [diff] [blame] | 506 | } |
Hugh Dickins | 42cb14b | 2015-11-05 18:50:05 -0800 | [diff] [blame] | 507 | local_irq_enable(); |
Christoph Lameter | b20a350 | 2006-03-22 00:09:12 -0800 | [diff] [blame] | 508 | |
Rafael Aquini | 78bd520 | 2012-12-11 16:02:31 -0800 | [diff] [blame] | 509 | return MIGRATEPAGE_SUCCESS; |
Christoph Lameter | b20a350 | 2006-03-22 00:09:12 -0800 | [diff] [blame] | 510 | } |
Matthew Wilcox (Oracle) | 3417013 | 2021-05-07 07:28:40 -0400 | [diff] [blame] | 511 | EXPORT_SYMBOL(folio_migrate_mapping); |
Christoph Lameter | b20a350 | 2006-03-22 00:09:12 -0800 | [diff] [blame] | 512 | |
| 513 | /* |
Naoya Horiguchi | 290408d | 2010-09-08 10:19:35 +0900 | [diff] [blame] | 514 | * The expected number of remaining references is the same as that |
Matthew Wilcox (Oracle) | 3417013 | 2021-05-07 07:28:40 -0400 | [diff] [blame] | 515 | * of folio_migrate_mapping(). |
Naoya Horiguchi | 290408d | 2010-09-08 10:19:35 +0900 | [diff] [blame] | 516 | */ |
| 517 | int migrate_huge_page_move_mapping(struct address_space *mapping, |
Matthew Wilcox (Oracle) | b890ec2 | 2022-06-06 10:47:21 -0400 | [diff] [blame] | 518 | struct folio *dst, struct folio *src) |
Naoya Horiguchi | 290408d | 2010-09-08 10:19:35 +0900 | [diff] [blame] | 519 | { |
Matthew Wilcox (Oracle) | b890ec2 | 2022-06-06 10:47:21 -0400 | [diff] [blame] | 520 | XA_STATE(xas, &mapping->i_pages, folio_index(src)); |
Naoya Horiguchi | 290408d | 2010-09-08 10:19:35 +0900 | [diff] [blame] | 521 | int expected_count; |
Naoya Horiguchi | 290408d | 2010-09-08 10:19:35 +0900 | [diff] [blame] | 522 | |
Matthew Wilcox | 89eb946 | 2017-12-04 04:35:16 -0500 | [diff] [blame] | 523 | xas_lock_irq(&xas); |
Matthew Wilcox (Oracle) | b890ec2 | 2022-06-06 10:47:21 -0400 | [diff] [blame] | 524 | expected_count = 2 + folio_has_private(src); |
| 525 | if (!folio_ref_freeze(src, expected_count)) { |
Matthew Wilcox | 89eb946 | 2017-12-04 04:35:16 -0500 | [diff] [blame] | 526 | xas_unlock_irq(&xas); |
Naoya Horiguchi | 290408d | 2010-09-08 10:19:35 +0900 | [diff] [blame] | 527 | return -EAGAIN; |
| 528 | } |
| 529 | |
Matthew Wilcox (Oracle) | b890ec2 | 2022-06-06 10:47:21 -0400 | [diff] [blame] | 530 | dst->index = src->index; |
| 531 | dst->mapping = src->mapping; |
Johannes Weiner | 6a93ca8 | 2016-03-15 14:57:19 -0700 | [diff] [blame] | 532 | |
Matthew Wilcox (Oracle) | b890ec2 | 2022-06-06 10:47:21 -0400 | [diff] [blame] | 533 | folio_get(dst); |
Naoya Horiguchi | 290408d | 2010-09-08 10:19:35 +0900 | [diff] [blame] | 534 | |
Matthew Wilcox (Oracle) | b890ec2 | 2022-06-06 10:47:21 -0400 | [diff] [blame] | 535 | xas_store(&xas, dst); |
Naoya Horiguchi | 290408d | 2010-09-08 10:19:35 +0900 | [diff] [blame] | 536 | |
Matthew Wilcox (Oracle) | b890ec2 | 2022-06-06 10:47:21 -0400 | [diff] [blame] | 537 | folio_ref_unfreeze(src, expected_count - 1); |
Naoya Horiguchi | 290408d | 2010-09-08 10:19:35 +0900 | [diff] [blame] | 538 | |
Matthew Wilcox | 89eb946 | 2017-12-04 04:35:16 -0500 | [diff] [blame] | 539 | xas_unlock_irq(&xas); |
Johannes Weiner | 6a93ca8 | 2016-03-15 14:57:19 -0700 | [diff] [blame] | 540 | |
Rafael Aquini | 78bd520 | 2012-12-11 16:02:31 -0800 | [diff] [blame] | 541 | return MIGRATEPAGE_SUCCESS; |
Naoya Horiguchi | 290408d | 2010-09-08 10:19:35 +0900 | [diff] [blame] | 542 | } |
| 543 | |
| 544 | /* |
Matthew Wilcox (Oracle) | 1913834 | 2021-05-07 15:26:29 -0400 | [diff] [blame] | 545 | * Copy the flags and some other ancillary information |
Christoph Lameter | b20a350 | 2006-03-22 00:09:12 -0800 | [diff] [blame] | 546 | */ |
Matthew Wilcox (Oracle) | 1913834 | 2021-05-07 15:26:29 -0400 | [diff] [blame] | 547 | void folio_migrate_flags(struct folio *newfolio, struct folio *folio) |
Christoph Lameter | b20a350 | 2006-03-22 00:09:12 -0800 | [diff] [blame] | 548 | { |
Rik van Riel | 7851a45 | 2013-10-07 11:29:23 +0100 | [diff] [blame] | 549 | int cpupid; |
| 550 | |
Matthew Wilcox (Oracle) | 1913834 | 2021-05-07 15:26:29 -0400 | [diff] [blame] | 551 | if (folio_test_error(folio)) |
| 552 | folio_set_error(newfolio); |
| 553 | if (folio_test_referenced(folio)) |
| 554 | folio_set_referenced(newfolio); |
| 555 | if (folio_test_uptodate(folio)) |
| 556 | folio_mark_uptodate(newfolio); |
| 557 | if (folio_test_clear_active(folio)) { |
| 558 | VM_BUG_ON_FOLIO(folio_test_unevictable(folio), folio); |
| 559 | folio_set_active(newfolio); |
| 560 | } else if (folio_test_clear_unevictable(folio)) |
| 561 | folio_set_unevictable(newfolio); |
| 562 | if (folio_test_workingset(folio)) |
| 563 | folio_set_workingset(newfolio); |
| 564 | if (folio_test_checked(folio)) |
| 565 | folio_set_checked(newfolio); |
David Hildenbrand | 6c28760 | 2022-05-09 18:20:44 -0700 | [diff] [blame] | 566 | /* |
| 567 | * PG_anon_exclusive (-> PG_mappedtodisk) is always migrated via |
| 568 | * migration entries. We can still have PG_anon_exclusive set on an |
| 569 | * effectively unmapped and unreferenced first sub-pages of an |
| 570 | * anonymous THP: we can simply copy it here via PG_mappedtodisk. |
| 571 | */ |
Matthew Wilcox (Oracle) | 1913834 | 2021-05-07 15:26:29 -0400 | [diff] [blame] | 572 | if (folio_test_mappedtodisk(folio)) |
| 573 | folio_set_mappedtodisk(newfolio); |
Christoph Lameter | b20a350 | 2006-03-22 00:09:12 -0800 | [diff] [blame] | 574 | |
Matthew Wilcox (Oracle) | 3417013 | 2021-05-07 07:28:40 -0400 | [diff] [blame] | 575 | /* Move dirty on pages not done by folio_migrate_mapping() */ |
Matthew Wilcox (Oracle) | 1913834 | 2021-05-07 15:26:29 -0400 | [diff] [blame] | 576 | if (folio_test_dirty(folio)) |
| 577 | folio_set_dirty(newfolio); |
Christoph Lameter | b20a350 | 2006-03-22 00:09:12 -0800 | [diff] [blame] | 578 | |
Matthew Wilcox (Oracle) | 1913834 | 2021-05-07 15:26:29 -0400 | [diff] [blame] | 579 | if (folio_test_young(folio)) |
| 580 | folio_set_young(newfolio); |
| 581 | if (folio_test_idle(folio)) |
| 582 | folio_set_idle(newfolio); |
Vladimir Davydov | 33c3fc7 | 2015-09-09 15:35:45 -0700 | [diff] [blame] | 583 | |
Rik van Riel | 7851a45 | 2013-10-07 11:29:23 +0100 | [diff] [blame] | 584 | /* |
| 585 | * Copy NUMA information to the new page, to prevent over-eager |
| 586 | * future migrations of this same page. |
| 587 | */ |
Matthew Wilcox (Oracle) | 1913834 | 2021-05-07 15:26:29 -0400 | [diff] [blame] | 588 | cpupid = page_cpupid_xchg_last(&folio->page, -1); |
Huang Ying | 3302453 | 2022-07-13 16:39:51 +0800 | [diff] [blame] | 589 | /* |
| 590 | * For memory tiering mode, when migrate between slow and fast |
| 591 | * memory node, reset cpupid, because that is used to record |
| 592 | * page access time in slow memory node. |
| 593 | */ |
| 594 | if (sysctl_numa_balancing_mode & NUMA_BALANCING_MEMORY_TIERING) { |
| 595 | bool f_toptier = node_is_toptier(page_to_nid(&folio->page)); |
| 596 | bool t_toptier = node_is_toptier(page_to_nid(&newfolio->page)); |
| 597 | |
| 598 | if (f_toptier != t_toptier) |
| 599 | cpupid = -1; |
| 600 | } |
Matthew Wilcox (Oracle) | 1913834 | 2021-05-07 15:26:29 -0400 | [diff] [blame] | 601 | page_cpupid_xchg_last(&newfolio->page, cpupid); |
Rik van Riel | 7851a45 | 2013-10-07 11:29:23 +0100 | [diff] [blame] | 602 | |
Matthew Wilcox (Oracle) | 1913834 | 2021-05-07 15:26:29 -0400 | [diff] [blame] | 603 | folio_migrate_ksm(newfolio, folio); |
Hugh Dickins | c8d6553 | 2013-02-22 16:35:10 -0800 | [diff] [blame] | 604 | /* |
| 605 | * Please do not reorder this without considering how mm/ksm.c's |
| 606 | * get_ksm_page() depends upon ksm_migrate_page() and PageSwapCache(). |
| 607 | */ |
Matthew Wilcox (Oracle) | 1913834 | 2021-05-07 15:26:29 -0400 | [diff] [blame] | 608 | if (folio_test_swapcache(folio)) |
| 609 | folio_clear_swapcache(folio); |
| 610 | folio_clear_private(folio); |
Muchun Song | ad2fa37 | 2021-06-30 18:47:21 -0700 | [diff] [blame] | 611 | |
| 612 | /* page->private contains hugetlb specific flags */ |
Matthew Wilcox (Oracle) | 1913834 | 2021-05-07 15:26:29 -0400 | [diff] [blame] | 613 | if (!folio_test_hugetlb(folio)) |
| 614 | folio->private = NULL; |
Christoph Lameter | b20a350 | 2006-03-22 00:09:12 -0800 | [diff] [blame] | 615 | |
| 616 | /* |
| 617 | * If any waiters have accumulated on the new page then |
| 618 | * wake them up. |
| 619 | */ |
Matthew Wilcox (Oracle) | 1913834 | 2021-05-07 15:26:29 -0400 | [diff] [blame] | 620 | if (folio_test_writeback(newfolio)) |
| 621 | folio_end_writeback(newfolio); |
Vlastimil Babka | d435edc | 2016-03-15 14:56:15 -0700 | [diff] [blame] | 622 | |
Yang Shi | 6aeff24 | 2020-04-06 20:04:21 -0700 | [diff] [blame] | 623 | /* |
| 624 | * PG_readahead shares the same bit with PG_reclaim. The above |
| 625 | * end_page_writeback() may clear PG_readahead mistakenly, so set the |
| 626 | * bit after that. |
| 627 | */ |
Matthew Wilcox (Oracle) | 1913834 | 2021-05-07 15:26:29 -0400 | [diff] [blame] | 628 | if (folio_test_readahead(folio)) |
| 629 | folio_set_readahead(newfolio); |
Yang Shi | 6aeff24 | 2020-04-06 20:04:21 -0700 | [diff] [blame] | 630 | |
Matthew Wilcox (Oracle) | 1913834 | 2021-05-07 15:26:29 -0400 | [diff] [blame] | 631 | folio_copy_owner(newfolio, folio); |
Johannes Weiner | 74485cf | 2016-03-15 14:57:54 -0700 | [diff] [blame] | 632 | |
Matthew Wilcox (Oracle) | 1913834 | 2021-05-07 15:26:29 -0400 | [diff] [blame] | 633 | if (!folio_test_hugetlb(folio)) |
Matthew Wilcox (Oracle) | d21bba2 | 2021-05-06 18:14:59 -0400 | [diff] [blame] | 634 | mem_cgroup_migrate(folio, newfolio); |
Christoph Lameter | b20a350 | 2006-03-22 00:09:12 -0800 | [diff] [blame] | 635 | } |
Matthew Wilcox (Oracle) | 1913834 | 2021-05-07 15:26:29 -0400 | [diff] [blame] | 636 | EXPORT_SYMBOL(folio_migrate_flags); |
Jérôme Glisse | 2916ecc | 2017-09-08 16:12:06 -0700 | [diff] [blame] | 637 | |
Matthew Wilcox (Oracle) | 715cbfd | 2021-05-07 15:05:06 -0400 | [diff] [blame] | 638 | void folio_migrate_copy(struct folio *newfolio, struct folio *folio) |
Jérôme Glisse | 2916ecc | 2017-09-08 16:12:06 -0700 | [diff] [blame] | 639 | { |
Matthew Wilcox (Oracle) | 715cbfd | 2021-05-07 15:05:06 -0400 | [diff] [blame] | 640 | folio_copy(newfolio, folio); |
| 641 | folio_migrate_flags(newfolio, folio); |
Jérôme Glisse | 2916ecc | 2017-09-08 16:12:06 -0700 | [diff] [blame] | 642 | } |
Matthew Wilcox (Oracle) | 715cbfd | 2021-05-07 15:05:06 -0400 | [diff] [blame] | 643 | EXPORT_SYMBOL(folio_migrate_copy); |
Christoph Lameter | b20a350 | 2006-03-22 00:09:12 -0800 | [diff] [blame] | 644 | |
Christoph Lameter | 1d8b85c | 2006-06-23 02:03:28 -0700 | [diff] [blame] | 645 | /************************************************************ |
| 646 | * Migration functions |
| 647 | ***********************************************************/ |
| 648 | |
Alistair Popple | 16ce101 | 2022-09-28 22:01:15 +1000 | [diff] [blame] | 649 | int migrate_folio_extra(struct address_space *mapping, struct folio *dst, |
| 650 | struct folio *src, enum migrate_mode mode, int extra_count) |
| 651 | { |
| 652 | int rc; |
| 653 | |
| 654 | BUG_ON(folio_test_writeback(src)); /* Writeback must be complete */ |
| 655 | |
| 656 | rc = folio_migrate_mapping(mapping, dst, src, extra_count); |
| 657 | |
| 658 | if (rc != MIGRATEPAGE_SUCCESS) |
| 659 | return rc; |
| 660 | |
| 661 | if (mode != MIGRATE_SYNC_NO_COPY) |
| 662 | folio_migrate_copy(dst, src); |
| 663 | else |
| 664 | folio_migrate_flags(dst, src); |
| 665 | return MIGRATEPAGE_SUCCESS; |
| 666 | } |
| 667 | |
Matthew Wilcox (Oracle) | 5418465 | 2022-06-06 10:27:41 -0400 | [diff] [blame] | 668 | /** |
| 669 | * migrate_folio() - Simple folio migration. |
| 670 | * @mapping: The address_space containing the folio. |
| 671 | * @dst: The folio to migrate the data to. |
| 672 | * @src: The folio containing the current data. |
| 673 | * @mode: How to migrate the page. |
Christoph Lameter | b20a350 | 2006-03-22 00:09:12 -0800 | [diff] [blame] | 674 | * |
Matthew Wilcox (Oracle) | 5418465 | 2022-06-06 10:27:41 -0400 | [diff] [blame] | 675 | * Common logic to directly migrate a single LRU folio suitable for |
| 676 | * folios that do not use PagePrivate/PagePrivate2. |
| 677 | * |
| 678 | * Folios are locked upon entry and exit. |
Christoph Lameter | b20a350 | 2006-03-22 00:09:12 -0800 | [diff] [blame] | 679 | */ |
Matthew Wilcox (Oracle) | 5418465 | 2022-06-06 10:27:41 -0400 | [diff] [blame] | 680 | int migrate_folio(struct address_space *mapping, struct folio *dst, |
| 681 | struct folio *src, enum migrate_mode mode) |
Christoph Lameter | b20a350 | 2006-03-22 00:09:12 -0800 | [diff] [blame] | 682 | { |
Alistair Popple | 16ce101 | 2022-09-28 22:01:15 +1000 | [diff] [blame] | 683 | return migrate_folio_extra(mapping, dst, src, mode, 0); |
Christoph Lameter | b20a350 | 2006-03-22 00:09:12 -0800 | [diff] [blame] | 684 | } |
Matthew Wilcox (Oracle) | 5418465 | 2022-06-06 10:27:41 -0400 | [diff] [blame] | 685 | EXPORT_SYMBOL(migrate_folio); |
Christoph Lameter | b20a350 | 2006-03-22 00:09:12 -0800 | [diff] [blame] | 686 | |
David Howells | 9361401 | 2006-09-30 20:45:40 +0200 | [diff] [blame] | 687 | #ifdef CONFIG_BLOCK |
Jan Kara | 84ade7c | 2018-12-28 00:39:09 -0800 | [diff] [blame] | 688 | /* Returns true if all buffers are successfully locked */ |
| 689 | static bool buffer_migrate_lock_buffers(struct buffer_head *head, |
| 690 | enum migrate_mode mode) |
| 691 | { |
| 692 | struct buffer_head *bh = head; |
Douglas Anderson | 4bb6dc7 | 2023-04-28 13:54:38 -0700 | [diff] [blame] | 693 | struct buffer_head *failed_bh; |
Jan Kara | 84ade7c | 2018-12-28 00:39:09 -0800 | [diff] [blame] | 694 | |
Jan Kara | 84ade7c | 2018-12-28 00:39:09 -0800 | [diff] [blame] | 695 | do { |
Jan Kara | 84ade7c | 2018-12-28 00:39:09 -0800 | [diff] [blame] | 696 | if (!trylock_buffer(bh)) { |
Douglas Anderson | 4bb6dc7 | 2023-04-28 13:54:38 -0700 | [diff] [blame] | 697 | if (mode == MIGRATE_ASYNC) |
| 698 | goto unlock; |
| 699 | if (mode == MIGRATE_SYNC_LIGHT && !buffer_uptodate(bh)) |
| 700 | goto unlock; |
| 701 | lock_buffer(bh); |
Jan Kara | 84ade7c | 2018-12-28 00:39:09 -0800 | [diff] [blame] | 702 | } |
| 703 | |
| 704 | bh = bh->b_this_page; |
| 705 | } while (bh != head); |
Douglas Anderson | 4bb6dc7 | 2023-04-28 13:54:38 -0700 | [diff] [blame] | 706 | |
Jan Kara | 84ade7c | 2018-12-28 00:39:09 -0800 | [diff] [blame] | 707 | return true; |
Douglas Anderson | 4bb6dc7 | 2023-04-28 13:54:38 -0700 | [diff] [blame] | 708 | |
| 709 | unlock: |
| 710 | /* We failed to lock the buffer and cannot stall. */ |
| 711 | failed_bh = bh; |
| 712 | bh = head; |
| 713 | while (bh != failed_bh) { |
| 714 | unlock_buffer(bh); |
| 715 | bh = bh->b_this_page; |
| 716 | } |
| 717 | |
| 718 | return false; |
Jan Kara | 84ade7c | 2018-12-28 00:39:09 -0800 | [diff] [blame] | 719 | } |
| 720 | |
Matthew Wilcox (Oracle) | 6723518 | 2022-06-06 10:20:31 -0400 | [diff] [blame] | 721 | static int __buffer_migrate_folio(struct address_space *mapping, |
| 722 | struct folio *dst, struct folio *src, enum migrate_mode mode, |
Jan Kara | 89cb088 | 2018-12-28 00:39:12 -0800 | [diff] [blame] | 723 | bool check_refs) |
Christoph Lameter | 1d8b85c | 2006-06-23 02:03:28 -0700 | [diff] [blame] | 724 | { |
Christoph Lameter | 1d8b85c | 2006-06-23 02:03:28 -0700 | [diff] [blame] | 725 | struct buffer_head *bh, *head; |
| 726 | int rc; |
Jan Kara | cc4f11e | 2018-12-28 00:39:05 -0800 | [diff] [blame] | 727 | int expected_count; |
Christoph Lameter | 1d8b85c | 2006-06-23 02:03:28 -0700 | [diff] [blame] | 728 | |
Matthew Wilcox (Oracle) | 6723518 | 2022-06-06 10:20:31 -0400 | [diff] [blame] | 729 | head = folio_buffers(src); |
| 730 | if (!head) |
Matthew Wilcox (Oracle) | 5418465 | 2022-06-06 10:27:41 -0400 | [diff] [blame] | 731 | return migrate_folio(mapping, dst, src, mode); |
Christoph Lameter | 1d8b85c | 2006-06-23 02:03:28 -0700 | [diff] [blame] | 732 | |
Jan Kara | cc4f11e | 2018-12-28 00:39:05 -0800 | [diff] [blame] | 733 | /* Check whether page does not have extra refs before we do more work */ |
Matthew Wilcox (Oracle) | 108ca83 | 2022-06-06 16:25:10 -0400 | [diff] [blame] | 734 | expected_count = folio_expected_refs(mapping, src); |
Matthew Wilcox (Oracle) | 6723518 | 2022-06-06 10:20:31 -0400 | [diff] [blame] | 735 | if (folio_ref_count(src) != expected_count) |
Jan Kara | cc4f11e | 2018-12-28 00:39:05 -0800 | [diff] [blame] | 736 | return -EAGAIN; |
| 737 | |
Jan Kara | cc4f11e | 2018-12-28 00:39:05 -0800 | [diff] [blame] | 738 | if (!buffer_migrate_lock_buffers(head, mode)) |
| 739 | return -EAGAIN; |
Christoph Lameter | 1d8b85c | 2006-06-23 02:03:28 -0700 | [diff] [blame] | 740 | |
Jan Kara | 89cb088 | 2018-12-28 00:39:12 -0800 | [diff] [blame] | 741 | if (check_refs) { |
| 742 | bool busy; |
| 743 | bool invalidated = false; |
| 744 | |
| 745 | recheck_buffers: |
| 746 | busy = false; |
| 747 | spin_lock(&mapping->private_lock); |
| 748 | bh = head; |
| 749 | do { |
| 750 | if (atomic_read(&bh->b_count)) { |
| 751 | busy = true; |
| 752 | break; |
| 753 | } |
| 754 | bh = bh->b_this_page; |
| 755 | } while (bh != head); |
Jan Kara | 89cb088 | 2018-12-28 00:39:12 -0800 | [diff] [blame] | 756 | if (busy) { |
| 757 | if (invalidated) { |
| 758 | rc = -EAGAIN; |
| 759 | goto unlock_buffers; |
| 760 | } |
Jan Kara | ebdf4de | 2019-08-02 21:48:47 -0700 | [diff] [blame] | 761 | spin_unlock(&mapping->private_lock); |
Jan Kara | 89cb088 | 2018-12-28 00:39:12 -0800 | [diff] [blame] | 762 | invalidate_bh_lrus(); |
| 763 | invalidated = true; |
| 764 | goto recheck_buffers; |
| 765 | } |
| 766 | } |
| 767 | |
Matthew Wilcox (Oracle) | 6723518 | 2022-06-06 10:20:31 -0400 | [diff] [blame] | 768 | rc = folio_migrate_mapping(mapping, dst, src, 0); |
Rafael Aquini | 78bd520 | 2012-12-11 16:02:31 -0800 | [diff] [blame] | 769 | if (rc != MIGRATEPAGE_SUCCESS) |
Jan Kara | cc4f11e | 2018-12-28 00:39:05 -0800 | [diff] [blame] | 770 | goto unlock_buffers; |
Christoph Lameter | 1d8b85c | 2006-06-23 02:03:28 -0700 | [diff] [blame] | 771 | |
Matthew Wilcox (Oracle) | 6723518 | 2022-06-06 10:20:31 -0400 | [diff] [blame] | 772 | folio_attach_private(dst, folio_detach_private(src)); |
Christoph Lameter | 1d8b85c | 2006-06-23 02:03:28 -0700 | [diff] [blame] | 773 | |
| 774 | bh = head; |
| 775 | do { |
Matthew Wilcox (Oracle) | 6723518 | 2022-06-06 10:20:31 -0400 | [diff] [blame] | 776 | set_bh_page(bh, &dst->page, bh_offset(bh)); |
Christoph Lameter | 1d8b85c | 2006-06-23 02:03:28 -0700 | [diff] [blame] | 777 | bh = bh->b_this_page; |
Christoph Lameter | 1d8b85c | 2006-06-23 02:03:28 -0700 | [diff] [blame] | 778 | } while (bh != head); |
| 779 | |
Jérôme Glisse | 2916ecc | 2017-09-08 16:12:06 -0700 | [diff] [blame] | 780 | if (mode != MIGRATE_SYNC_NO_COPY) |
Matthew Wilcox (Oracle) | 6723518 | 2022-06-06 10:20:31 -0400 | [diff] [blame] | 781 | folio_migrate_copy(dst, src); |
Jérôme Glisse | 2916ecc | 2017-09-08 16:12:06 -0700 | [diff] [blame] | 782 | else |
Matthew Wilcox (Oracle) | 6723518 | 2022-06-06 10:20:31 -0400 | [diff] [blame] | 783 | folio_migrate_flags(dst, src); |
Christoph Lameter | 1d8b85c | 2006-06-23 02:03:28 -0700 | [diff] [blame] | 784 | |
Jan Kara | cc4f11e | 2018-12-28 00:39:05 -0800 | [diff] [blame] | 785 | rc = MIGRATEPAGE_SUCCESS; |
| 786 | unlock_buffers: |
Jan Kara | ebdf4de | 2019-08-02 21:48:47 -0700 | [diff] [blame] | 787 | if (check_refs) |
| 788 | spin_unlock(&mapping->private_lock); |
Christoph Lameter | 1d8b85c | 2006-06-23 02:03:28 -0700 | [diff] [blame] | 789 | bh = head; |
| 790 | do { |
| 791 | unlock_buffer(bh); |
Christoph Lameter | 1d8b85c | 2006-06-23 02:03:28 -0700 | [diff] [blame] | 792 | bh = bh->b_this_page; |
Christoph Lameter | 1d8b85c | 2006-06-23 02:03:28 -0700 | [diff] [blame] | 793 | } while (bh != head); |
| 794 | |
Jan Kara | cc4f11e | 2018-12-28 00:39:05 -0800 | [diff] [blame] | 795 | return rc; |
Christoph Lameter | 1d8b85c | 2006-06-23 02:03:28 -0700 | [diff] [blame] | 796 | } |
Jan Kara | 89cb088 | 2018-12-28 00:39:12 -0800 | [diff] [blame] | 797 | |
Matthew Wilcox (Oracle) | 6723518 | 2022-06-06 10:20:31 -0400 | [diff] [blame] | 798 | /** |
| 799 | * buffer_migrate_folio() - Migration function for folios with buffers. |
| 800 | * @mapping: The address space containing @src. |
| 801 | * @dst: The folio to migrate to. |
| 802 | * @src: The folio to migrate from. |
| 803 | * @mode: How to migrate the folio. |
| 804 | * |
| 805 | * This function can only be used if the underlying filesystem guarantees |
| 806 | * that no other references to @src exist. For example attached buffer |
| 807 | * heads are accessed only under the folio lock. If your filesystem cannot |
| 808 | * provide this guarantee, buffer_migrate_folio_norefs() may be more |
| 809 | * appropriate. |
| 810 | * |
| 811 | * Return: 0 on success or a negative errno on failure. |
Jan Kara | 89cb088 | 2018-12-28 00:39:12 -0800 | [diff] [blame] | 812 | */ |
Matthew Wilcox (Oracle) | 6723518 | 2022-06-06 10:20:31 -0400 | [diff] [blame] | 813 | int buffer_migrate_folio(struct address_space *mapping, |
| 814 | struct folio *dst, struct folio *src, enum migrate_mode mode) |
Jan Kara | 89cb088 | 2018-12-28 00:39:12 -0800 | [diff] [blame] | 815 | { |
Matthew Wilcox (Oracle) | 6723518 | 2022-06-06 10:20:31 -0400 | [diff] [blame] | 816 | return __buffer_migrate_folio(mapping, dst, src, mode, false); |
Jan Kara | 89cb088 | 2018-12-28 00:39:12 -0800 | [diff] [blame] | 817 | } |
Matthew Wilcox (Oracle) | 6723518 | 2022-06-06 10:20:31 -0400 | [diff] [blame] | 818 | EXPORT_SYMBOL(buffer_migrate_folio); |
Jan Kara | 89cb088 | 2018-12-28 00:39:12 -0800 | [diff] [blame] | 819 | |
Matthew Wilcox (Oracle) | 6723518 | 2022-06-06 10:20:31 -0400 | [diff] [blame] | 820 | /** |
| 821 | * buffer_migrate_folio_norefs() - Migration function for folios with buffers. |
| 822 | * @mapping: The address space containing @src. |
| 823 | * @dst: The folio to migrate to. |
| 824 | * @src: The folio to migrate from. |
| 825 | * @mode: How to migrate the folio. |
| 826 | * |
| 827 | * Like buffer_migrate_folio() except that this variant is more careful |
| 828 | * and checks that there are also no buffer head references. This function |
| 829 | * is the right one for mappings where buffer heads are directly looked |
| 830 | * up and referenced (such as block device mappings). |
| 831 | * |
| 832 | * Return: 0 on success or a negative errno on failure. |
Jan Kara | 89cb088 | 2018-12-28 00:39:12 -0800 | [diff] [blame] | 833 | */ |
Matthew Wilcox (Oracle) | 6723518 | 2022-06-06 10:20:31 -0400 | [diff] [blame] | 834 | int buffer_migrate_folio_norefs(struct address_space *mapping, |
| 835 | struct folio *dst, struct folio *src, enum migrate_mode mode) |
Jan Kara | 89cb088 | 2018-12-28 00:39:12 -0800 | [diff] [blame] | 836 | { |
Matthew Wilcox (Oracle) | 6723518 | 2022-06-06 10:20:31 -0400 | [diff] [blame] | 837 | return __buffer_migrate_folio(mapping, dst, src, mode, true); |
Jan Kara | 89cb088 | 2018-12-28 00:39:12 -0800 | [diff] [blame] | 838 | } |
Jan Kara | e26355e | 2022-12-07 12:27:14 +0100 | [diff] [blame] | 839 | EXPORT_SYMBOL_GPL(buffer_migrate_folio_norefs); |
David Howells | 9361401 | 2006-09-30 20:45:40 +0200 | [diff] [blame] | 840 | #endif |
Christoph Lameter | 1d8b85c | 2006-06-23 02:03:28 -0700 | [diff] [blame] | 841 | |
Matthew Wilcox (Oracle) | 2ec810d | 2022-06-06 12:55:08 -0400 | [diff] [blame] | 842 | int filemap_migrate_folio(struct address_space *mapping, |
| 843 | struct folio *dst, struct folio *src, enum migrate_mode mode) |
| 844 | { |
| 845 | int ret; |
| 846 | |
| 847 | ret = folio_migrate_mapping(mapping, dst, src, 0); |
| 848 | if (ret != MIGRATEPAGE_SUCCESS) |
| 849 | return ret; |
| 850 | |
| 851 | if (folio_get_private(src)) |
| 852 | folio_attach_private(dst, folio_detach_private(src)); |
| 853 | |
| 854 | if (mode != MIGRATE_SYNC_NO_COPY) |
| 855 | folio_migrate_copy(dst, src); |
| 856 | else |
| 857 | folio_migrate_flags(dst, src); |
| 858 | return MIGRATEPAGE_SUCCESS; |
| 859 | } |
| 860 | EXPORT_SYMBOL_GPL(filemap_migrate_folio); |
| 861 | |
Christoph Lameter | 04e62a2 | 2006-06-23 02:03:38 -0700 | [diff] [blame] | 862 | /* |
Matthew Wilcox (Oracle) | 2be7fa1 | 2022-06-06 09:41:03 -0400 | [diff] [blame] | 863 | * Writeback a folio to clean the dirty state |
Christoph Lameter | 04e62a2 | 2006-06-23 02:03:38 -0700 | [diff] [blame] | 864 | */ |
Matthew Wilcox (Oracle) | 2be7fa1 | 2022-06-06 09:41:03 -0400 | [diff] [blame] | 865 | static int writeout(struct address_space *mapping, struct folio *folio) |
Christoph Lameter | 04e62a2 | 2006-06-23 02:03:38 -0700 | [diff] [blame] | 866 | { |
| 867 | struct writeback_control wbc = { |
| 868 | .sync_mode = WB_SYNC_NONE, |
| 869 | .nr_to_write = 1, |
| 870 | .range_start = 0, |
| 871 | .range_end = LLONG_MAX, |
Christoph Lameter | 04e62a2 | 2006-06-23 02:03:38 -0700 | [diff] [blame] | 872 | .for_reclaim = 1 |
| 873 | }; |
| 874 | int rc; |
| 875 | |
| 876 | if (!mapping->a_ops->writepage) |
| 877 | /* No write method for the address space */ |
| 878 | return -EINVAL; |
| 879 | |
Matthew Wilcox (Oracle) | 2be7fa1 | 2022-06-06 09:41:03 -0400 | [diff] [blame] | 880 | if (!folio_clear_dirty_for_io(folio)) |
Christoph Lameter | 04e62a2 | 2006-06-23 02:03:38 -0700 | [diff] [blame] | 881 | /* Someone else already triggered a write */ |
| 882 | return -EAGAIN; |
| 883 | |
| 884 | /* |
Matthew Wilcox (Oracle) | 2be7fa1 | 2022-06-06 09:41:03 -0400 | [diff] [blame] | 885 | * A dirty folio may imply that the underlying filesystem has |
| 886 | * the folio on some queue. So the folio must be clean for |
| 887 | * migration. Writeout may mean we lose the lock and the |
| 888 | * folio state is no longer what we checked for earlier. |
Christoph Lameter | 04e62a2 | 2006-06-23 02:03:38 -0700 | [diff] [blame] | 889 | * At this point we know that the migration attempt cannot |
| 890 | * be successful. |
| 891 | */ |
Matthew Wilcox (Oracle) | 4eecb8b | 2022-01-28 23:32:59 -0500 | [diff] [blame] | 892 | remove_migration_ptes(folio, folio, false); |
Christoph Lameter | 04e62a2 | 2006-06-23 02:03:38 -0700 | [diff] [blame] | 893 | |
Matthew Wilcox (Oracle) | 2be7fa1 | 2022-06-06 09:41:03 -0400 | [diff] [blame] | 894 | rc = mapping->a_ops->writepage(&folio->page, &wbc); |
Christoph Lameter | 04e62a2 | 2006-06-23 02:03:38 -0700 | [diff] [blame] | 895 | |
| 896 | if (rc != AOP_WRITEPAGE_ACTIVATE) |
| 897 | /* unlocked. Relock */ |
Matthew Wilcox (Oracle) | 2be7fa1 | 2022-06-06 09:41:03 -0400 | [diff] [blame] | 898 | folio_lock(folio); |
Christoph Lameter | 04e62a2 | 2006-06-23 02:03:38 -0700 | [diff] [blame] | 899 | |
Hugh Dickins | bda8550 | 2008-11-19 15:36:36 -0800 | [diff] [blame] | 900 | return (rc < 0) ? -EIO : -EAGAIN; |
Christoph Lameter | 04e62a2 | 2006-06-23 02:03:38 -0700 | [diff] [blame] | 901 | } |
| 902 | |
| 903 | /* |
| 904 | * Default handling if a filesystem does not provide a migration function. |
| 905 | */ |
Matthew Wilcox (Oracle) | 8faa8ef | 2022-06-06 09:34:36 -0400 | [diff] [blame] | 906 | static int fallback_migrate_folio(struct address_space *mapping, |
| 907 | struct folio *dst, struct folio *src, enum migrate_mode mode) |
Christoph Lameter | 8351a6e | 2006-06-23 02:03:33 -0700 | [diff] [blame] | 908 | { |
Matthew Wilcox (Oracle) | 8faa8ef | 2022-06-06 09:34:36 -0400 | [diff] [blame] | 909 | if (folio_test_dirty(src)) { |
| 910 | /* Only writeback folios in full synchronous migration */ |
Jérôme Glisse | 2916ecc | 2017-09-08 16:12:06 -0700 | [diff] [blame] | 911 | switch (mode) { |
| 912 | case MIGRATE_SYNC: |
| 913 | case MIGRATE_SYNC_NO_COPY: |
| 914 | break; |
| 915 | default: |
Mel Gorman | b969c4ab | 2012-01-12 17:19:34 -0800 | [diff] [blame] | 916 | return -EBUSY; |
Jérôme Glisse | 2916ecc | 2017-09-08 16:12:06 -0700 | [diff] [blame] | 917 | } |
Matthew Wilcox (Oracle) | 2be7fa1 | 2022-06-06 09:41:03 -0400 | [diff] [blame] | 918 | return writeout(mapping, src); |
Mel Gorman | b969c4ab | 2012-01-12 17:19:34 -0800 | [diff] [blame] | 919 | } |
Christoph Lameter | 8351a6e | 2006-06-23 02:03:33 -0700 | [diff] [blame] | 920 | |
| 921 | /* |
| 922 | * Buffers may be managed in a filesystem specific way. |
| 923 | * We must have no buffers or drop them. |
| 924 | */ |
Matthew Wilcox (Oracle) | 8faa8ef | 2022-06-06 09:34:36 -0400 | [diff] [blame] | 925 | if (folio_test_private(src) && |
| 926 | !filemap_release_folio(src, GFP_KERNEL)) |
Mel Gorman | 806031b | 2019-03-05 15:44:43 -0800 | [diff] [blame] | 927 | return mode == MIGRATE_SYNC ? -EAGAIN : -EBUSY; |
Christoph Lameter | 8351a6e | 2006-06-23 02:03:33 -0700 | [diff] [blame] | 928 | |
Matthew Wilcox (Oracle) | 5418465 | 2022-06-06 10:27:41 -0400 | [diff] [blame] | 929 | return migrate_folio(mapping, dst, src, mode); |
Christoph Lameter | 8351a6e | 2006-06-23 02:03:33 -0700 | [diff] [blame] | 930 | } |
| 931 | |
Christoph Lameter | 1d8b85c | 2006-06-23 02:03:28 -0700 | [diff] [blame] | 932 | /* |
Christoph Lameter | e24f0b8 | 2006-06-23 02:03:51 -0700 | [diff] [blame] | 933 | * Move a page to a newly allocated page |
| 934 | * The page is locked and all ptes have been successfully removed. |
| 935 | * |
| 936 | * The new page will have replaced the old page if this function |
| 937 | * is successful. |
Lee Schermerhorn | 894bc31 | 2008-10-18 20:26:39 -0700 | [diff] [blame] | 938 | * |
| 939 | * Return value: |
| 940 | * < 0 - error code |
Rafael Aquini | 78bd520 | 2012-12-11 16:02:31 -0800 | [diff] [blame] | 941 | * MIGRATEPAGE_SUCCESS - success |
Christoph Lameter | e24f0b8 | 2006-06-23 02:03:51 -0700 | [diff] [blame] | 942 | */ |
Matthew Wilcox (Oracle) | e7e3ffe | 2022-05-12 20:23:05 -0700 | [diff] [blame] | 943 | static int move_to_new_folio(struct folio *dst, struct folio *src, |
Hugh Dickins | 5c3f9a6 | 2015-11-05 18:49:53 -0800 | [diff] [blame] | 944 | enum migrate_mode mode) |
Christoph Lameter | e24f0b8 | 2006-06-23 02:03:51 -0700 | [diff] [blame] | 945 | { |
Minchan Kim | bda807d | 2016-07-26 15:23:05 -0700 | [diff] [blame] | 946 | int rc = -EAGAIN; |
Matthew Wilcox (Oracle) | e7e3ffe | 2022-05-12 20:23:05 -0700 | [diff] [blame] | 947 | bool is_lru = !__PageMovable(&src->page); |
Christoph Lameter | e24f0b8 | 2006-06-23 02:03:51 -0700 | [diff] [blame] | 948 | |
Matthew Wilcox (Oracle) | e7e3ffe | 2022-05-12 20:23:05 -0700 | [diff] [blame] | 949 | VM_BUG_ON_FOLIO(!folio_test_locked(src), src); |
| 950 | VM_BUG_ON_FOLIO(!folio_test_locked(dst), dst); |
Christoph Lameter | e24f0b8 | 2006-06-23 02:03:51 -0700 | [diff] [blame] | 951 | |
Minchan Kim | bda807d | 2016-07-26 15:23:05 -0700 | [diff] [blame] | 952 | if (likely(is_lru)) { |
Matthew Wilcox (Oracle) | 68f2736 | 2022-06-07 15:38:48 -0400 | [diff] [blame] | 953 | struct address_space *mapping = folio_mapping(src); |
| 954 | |
Minchan Kim | bda807d | 2016-07-26 15:23:05 -0700 | [diff] [blame] | 955 | if (!mapping) |
Matthew Wilcox (Oracle) | 5418465 | 2022-06-06 10:27:41 -0400 | [diff] [blame] | 956 | rc = migrate_folio(mapping, dst, src, mode); |
Matthew Wilcox (Oracle) | 5490da4 | 2022-06-06 09:00:16 -0400 | [diff] [blame] | 957 | else if (mapping->a_ops->migrate_folio) |
Minchan Kim | bda807d | 2016-07-26 15:23:05 -0700 | [diff] [blame] | 958 | /* |
Matthew Wilcox (Oracle) | 5490da4 | 2022-06-06 09:00:16 -0400 | [diff] [blame] | 959 | * Most folios have a mapping and most filesystems |
| 960 | * provide a migrate_folio callback. Anonymous folios |
Minchan Kim | bda807d | 2016-07-26 15:23:05 -0700 | [diff] [blame] | 961 | * are part of swap space which also has its own |
Matthew Wilcox (Oracle) | 5490da4 | 2022-06-06 09:00:16 -0400 | [diff] [blame] | 962 | * migrate_folio callback. This is the most common path |
Minchan Kim | bda807d | 2016-07-26 15:23:05 -0700 | [diff] [blame] | 963 | * for page migration. |
| 964 | */ |
Matthew Wilcox (Oracle) | 5490da4 | 2022-06-06 09:00:16 -0400 | [diff] [blame] | 965 | rc = mapping->a_ops->migrate_folio(mapping, dst, src, |
| 966 | mode); |
Minchan Kim | bda807d | 2016-07-26 15:23:05 -0700 | [diff] [blame] | 967 | else |
Matthew Wilcox (Oracle) | 8faa8ef | 2022-06-06 09:34:36 -0400 | [diff] [blame] | 968 | rc = fallback_migrate_folio(mapping, dst, src, mode); |
Minchan Kim | bda807d | 2016-07-26 15:23:05 -0700 | [diff] [blame] | 969 | } else { |
Matthew Wilcox (Oracle) | 68f2736 | 2022-06-07 15:38:48 -0400 | [diff] [blame] | 970 | const struct movable_operations *mops; |
| 971 | |
Christoph Lameter | e24f0b8 | 2006-06-23 02:03:51 -0700 | [diff] [blame] | 972 | /* |
Minchan Kim | bda807d | 2016-07-26 15:23:05 -0700 | [diff] [blame] | 973 | * In case of non-lru page, it could be released after |
| 974 | * isolation step. In that case, we shouldn't try migration. |
Christoph Lameter | e24f0b8 | 2006-06-23 02:03:51 -0700 | [diff] [blame] | 975 | */ |
Matthew Wilcox (Oracle) | e7e3ffe | 2022-05-12 20:23:05 -0700 | [diff] [blame] | 976 | VM_BUG_ON_FOLIO(!folio_test_isolated(src), src); |
| 977 | if (!folio_test_movable(src)) { |
Minchan Kim | bda807d | 2016-07-26 15:23:05 -0700 | [diff] [blame] | 978 | rc = MIGRATEPAGE_SUCCESS; |
Matthew Wilcox (Oracle) | e7e3ffe | 2022-05-12 20:23:05 -0700 | [diff] [blame] | 979 | folio_clear_isolated(src); |
Minchan Kim | bda807d | 2016-07-26 15:23:05 -0700 | [diff] [blame] | 980 | goto out; |
| 981 | } |
| 982 | |
Vishal Moola (Oracle) | da707a6 | 2023-01-30 13:43:50 -0800 | [diff] [blame] | 983 | mops = folio_movable_ops(src); |
Matthew Wilcox (Oracle) | 68f2736 | 2022-06-07 15:38:48 -0400 | [diff] [blame] | 984 | rc = mops->migrate_page(&dst->page, &src->page, mode); |
Minchan Kim | bda807d | 2016-07-26 15:23:05 -0700 | [diff] [blame] | 985 | WARN_ON_ONCE(rc == MIGRATEPAGE_SUCCESS && |
Matthew Wilcox (Oracle) | e7e3ffe | 2022-05-12 20:23:05 -0700 | [diff] [blame] | 986 | !folio_test_isolated(src)); |
Minchan Kim | bda807d | 2016-07-26 15:23:05 -0700 | [diff] [blame] | 987 | } |
Christoph Lameter | e24f0b8 | 2006-06-23 02:03:51 -0700 | [diff] [blame] | 988 | |
Hugh Dickins | 5c3f9a6 | 2015-11-05 18:49:53 -0800 | [diff] [blame] | 989 | /* |
Matthew Wilcox (Oracle) | e7e3ffe | 2022-05-12 20:23:05 -0700 | [diff] [blame] | 990 | * When successful, old pagecache src->mapping must be cleared before |
| 991 | * src is freed; but stats require that PageAnon be left as PageAnon. |
Hugh Dickins | 5c3f9a6 | 2015-11-05 18:49:53 -0800 | [diff] [blame] | 992 | */ |
| 993 | if (rc == MIGRATEPAGE_SUCCESS) { |
Matthew Wilcox (Oracle) | e7e3ffe | 2022-05-12 20:23:05 -0700 | [diff] [blame] | 994 | if (__PageMovable(&src->page)) { |
| 995 | VM_BUG_ON_FOLIO(!folio_test_isolated(src), src); |
Minchan Kim | bda807d | 2016-07-26 15:23:05 -0700 | [diff] [blame] | 996 | |
| 997 | /* |
| 998 | * We clear PG_movable under page_lock so any compactor |
| 999 | * cannot try to migrate this page. |
| 1000 | */ |
Matthew Wilcox (Oracle) | e7e3ffe | 2022-05-12 20:23:05 -0700 | [diff] [blame] | 1001 | folio_clear_isolated(src); |
Minchan Kim | bda807d | 2016-07-26 15:23:05 -0700 | [diff] [blame] | 1002 | } |
| 1003 | |
| 1004 | /* |
Matthew Wilcox (Oracle) | e7e3ffe | 2022-05-12 20:23:05 -0700 | [diff] [blame] | 1005 | * Anonymous and movable src->mapping will be cleared by |
Minchan Kim | bda807d | 2016-07-26 15:23:05 -0700 | [diff] [blame] | 1006 | * free_pages_prepare so don't reset it here for keeping |
| 1007 | * the type to work PageAnon, for example. |
| 1008 | */ |
Matthew Wilcox (Oracle) | e7e3ffe | 2022-05-12 20:23:05 -0700 | [diff] [blame] | 1009 | if (!folio_mapping_flags(src)) |
| 1010 | src->mapping = NULL; |
Lars Persson | d2b2c6dd | 2019-03-28 20:44:28 -0700 | [diff] [blame] | 1011 | |
Matthew Wilcox (Oracle) | e7e3ffe | 2022-05-12 20:23:05 -0700 | [diff] [blame] | 1012 | if (likely(!folio_is_zone_device(dst))) |
| 1013 | flush_dcache_folio(dst); |
Mel Gorman | 3fe2011 | 2010-05-24 14:32:20 -0700 | [diff] [blame] | 1014 | } |
Minchan Kim | bda807d | 2016-07-26 15:23:05 -0700 | [diff] [blame] | 1015 | out: |
Christoph Lameter | e24f0b8 | 2006-06-23 02:03:51 -0700 | [diff] [blame] | 1016 | return rc; |
| 1017 | } |
| 1018 | |
Huang Ying | 64c8902 | 2023-02-13 20:34:39 +0800 | [diff] [blame] | 1019 | /* |
| 1020 | * To record some information during migration, we use some unused |
| 1021 | * fields (mapping and private) of struct folio of the newly allocated |
| 1022 | * destination folio. This is safe because nobody is using them |
| 1023 | * except us. |
| 1024 | */ |
Linus Torvalds | e77d587 | 2023-03-04 14:03:27 -0800 | [diff] [blame] | 1025 | union migration_ptr { |
| 1026 | struct anon_vma *anon_vma; |
| 1027 | struct address_space *mapping; |
| 1028 | }; |
Huang Ying | 64c8902 | 2023-02-13 20:34:39 +0800 | [diff] [blame] | 1029 | static void __migrate_folio_record(struct folio *dst, |
| 1030 | unsigned long page_was_mapped, |
| 1031 | struct anon_vma *anon_vma) |
Christoph Lameter | e24f0b8 | 2006-06-23 02:03:51 -0700 | [diff] [blame] | 1032 | { |
Linus Torvalds | e77d587 | 2023-03-04 14:03:27 -0800 | [diff] [blame] | 1033 | union migration_ptr ptr = { .anon_vma = anon_vma }; |
| 1034 | dst->mapping = ptr.mapping; |
Huang Ying | 64c8902 | 2023-02-13 20:34:39 +0800 | [diff] [blame] | 1035 | dst->private = (void *)page_was_mapped; |
| 1036 | } |
| 1037 | |
| 1038 | static void __migrate_folio_extract(struct folio *dst, |
| 1039 | int *page_was_mappedp, |
| 1040 | struct anon_vma **anon_vmap) |
| 1041 | { |
Linus Torvalds | e77d587 | 2023-03-04 14:03:27 -0800 | [diff] [blame] | 1042 | union migration_ptr ptr = { .mapping = dst->mapping }; |
| 1043 | *anon_vmap = ptr.anon_vma; |
Huang Ying | 64c8902 | 2023-02-13 20:34:39 +0800 | [diff] [blame] | 1044 | *page_was_mappedp = (unsigned long)dst->private; |
| 1045 | dst->mapping = NULL; |
| 1046 | dst->private = NULL; |
| 1047 | } |
| 1048 | |
Huang Ying | 5dfab10 | 2023-02-13 20:34:40 +0800 | [diff] [blame] | 1049 | /* Restore the source folio to the original state upon failure */ |
| 1050 | static void migrate_folio_undo_src(struct folio *src, |
| 1051 | int page_was_mapped, |
| 1052 | struct anon_vma *anon_vma, |
Huang Ying | ebe75e4 | 2023-02-13 20:34:42 +0800 | [diff] [blame] | 1053 | bool locked, |
Huang Ying | 5dfab10 | 2023-02-13 20:34:40 +0800 | [diff] [blame] | 1054 | struct list_head *ret) |
| 1055 | { |
| 1056 | if (page_was_mapped) |
| 1057 | remove_migration_ptes(src, src, false); |
| 1058 | /* Drop an anon_vma reference if we took one */ |
| 1059 | if (anon_vma) |
| 1060 | put_anon_vma(anon_vma); |
Huang Ying | ebe75e4 | 2023-02-13 20:34:42 +0800 | [diff] [blame] | 1061 | if (locked) |
| 1062 | folio_unlock(src); |
| 1063 | if (ret) |
| 1064 | list_move_tail(&src->lru, ret); |
Huang Ying | 5dfab10 | 2023-02-13 20:34:40 +0800 | [diff] [blame] | 1065 | } |
| 1066 | |
| 1067 | /* Restore the destination folio to the original state upon failure */ |
Matthew Wilcox (Oracle) | 4e096ae | 2023-05-13 01:11:01 +0100 | [diff] [blame] | 1068 | static void migrate_folio_undo_dst(struct folio *dst, bool locked, |
| 1069 | free_folio_t put_new_folio, unsigned long private) |
Huang Ying | 5dfab10 | 2023-02-13 20:34:40 +0800 | [diff] [blame] | 1070 | { |
Huang Ying | ebe75e4 | 2023-02-13 20:34:42 +0800 | [diff] [blame] | 1071 | if (locked) |
| 1072 | folio_unlock(dst); |
Matthew Wilcox (Oracle) | 4e096ae | 2023-05-13 01:11:01 +0100 | [diff] [blame] | 1073 | if (put_new_folio) |
| 1074 | put_new_folio(dst, private); |
Huang Ying | 5dfab10 | 2023-02-13 20:34:40 +0800 | [diff] [blame] | 1075 | else |
| 1076 | folio_put(dst); |
| 1077 | } |
| 1078 | |
Huang Ying | 64c8902 | 2023-02-13 20:34:39 +0800 | [diff] [blame] | 1079 | /* Cleanup src folio upon migration success */ |
| 1080 | static void migrate_folio_done(struct folio *src, |
| 1081 | enum migrate_reason reason) |
| 1082 | { |
| 1083 | /* |
| 1084 | * Compaction can migrate also non-LRU pages which are |
| 1085 | * not accounted to NR_ISOLATED_*. They can be recognized |
| 1086 | * as __PageMovable |
| 1087 | */ |
| 1088 | if (likely(!__folio_test_movable(src))) |
| 1089 | mod_node_page_state(folio_pgdat(src), NR_ISOLATED_ANON + |
| 1090 | folio_is_file_lru(src), -folio_nr_pages(src)); |
| 1091 | |
| 1092 | if (reason != MR_MEMORY_FAILURE) |
| 1093 | /* We release the page in page_handle_poison. */ |
| 1094 | folio_put(src); |
| 1095 | } |
| 1096 | |
Huang Ying | ebe75e4 | 2023-02-13 20:34:42 +0800 | [diff] [blame] | 1097 | /* Obtain the lock on page, remove all ptes. */ |
Matthew Wilcox (Oracle) | 4e096ae | 2023-05-13 01:11:01 +0100 | [diff] [blame] | 1098 | static int migrate_folio_unmap(new_folio_t get_new_folio, |
| 1099 | free_folio_t put_new_folio, unsigned long private, |
| 1100 | struct folio *src, struct folio **dstp, enum migrate_mode mode, |
| 1101 | enum migrate_reason reason, struct list_head *ret) |
Christoph Lameter | e24f0b8 | 2006-06-23 02:03:51 -0700 | [diff] [blame] | 1102 | { |
Huang Ying | ebe75e4 | 2023-02-13 20:34:42 +0800 | [diff] [blame] | 1103 | struct folio *dst; |
Minchan Kim | 0dabec9 | 2011-10-31 17:06:57 -0700 | [diff] [blame] | 1104 | int rc = -EAGAIN; |
Huang Ying | 64c8902 | 2023-02-13 20:34:39 +0800 | [diff] [blame] | 1105 | int page_was_mapped = 0; |
Mel Gorman | 3f6c827 | 2010-05-24 14:32:17 -0700 | [diff] [blame] | 1106 | struct anon_vma *anon_vma = NULL; |
Matthew Wilcox (Oracle) | 682a71a | 2022-09-02 20:46:46 +0100 | [diff] [blame] | 1107 | bool is_lru = !__PageMovable(&src->page); |
Huang Ying | ebe75e4 | 2023-02-13 20:34:42 +0800 | [diff] [blame] | 1108 | bool locked = false; |
| 1109 | bool dst_locked = false; |
| 1110 | |
Huang Ying | ebe75e4 | 2023-02-13 20:34:42 +0800 | [diff] [blame] | 1111 | if (folio_ref_count(src) == 1) { |
| 1112 | /* Folio was freed from under us. So we are done. */ |
| 1113 | folio_clear_active(src); |
| 1114 | folio_clear_unevictable(src); |
| 1115 | /* free_pages_prepare() will clear PG_isolated. */ |
| 1116 | list_del(&src->lru); |
| 1117 | migrate_folio_done(src, reason); |
| 1118 | return MIGRATEPAGE_SUCCESS; |
| 1119 | } |
| 1120 | |
Matthew Wilcox (Oracle) | 4e096ae | 2023-05-13 01:11:01 +0100 | [diff] [blame] | 1121 | dst = get_new_folio(src, private); |
| 1122 | if (!dst) |
Huang Ying | ebe75e4 | 2023-02-13 20:34:42 +0800 | [diff] [blame] | 1123 | return -ENOMEM; |
Huang Ying | ebe75e4 | 2023-02-13 20:34:42 +0800 | [diff] [blame] | 1124 | *dstp = dst; |
| 1125 | |
| 1126 | dst->private = NULL; |
Christoph Lameter | 95a402c | 2006-06-23 02:03:53 -0700 | [diff] [blame] | 1127 | |
Matthew Wilcox (Oracle) | 682a71a | 2022-09-02 20:46:46 +0100 | [diff] [blame] | 1128 | if (!folio_trylock(src)) { |
Huang Ying | 2ef7dbb | 2023-03-03 11:01:55 +0800 | [diff] [blame] | 1129 | if (mode == MIGRATE_ASYNC) |
Minchan Kim | 0dabec9 | 2011-10-31 17:06:57 -0700 | [diff] [blame] | 1130 | goto out; |
Mel Gorman | 3e7d344 | 2011-01-13 15:45:56 -0800 | [diff] [blame] | 1131 | |
| 1132 | /* |
| 1133 | * It's not safe for direct compaction to call lock_page. |
| 1134 | * For example, during page readahead pages are added locked |
| 1135 | * to the LRU. Later, when the IO completes the pages are |
| 1136 | * marked uptodate and unlocked. However, the queueing |
| 1137 | * could be merging multiple pages for one bio (e.g. |
Matthew Wilcox (Oracle) | d438834 | 2020-06-01 21:47:02 -0700 | [diff] [blame] | 1138 | * mpage_readahead). If an allocation happens for the |
Mel Gorman | 3e7d344 | 2011-01-13 15:45:56 -0800 | [diff] [blame] | 1139 | * second or third page, the process can end up locking |
| 1140 | * the same page twice and deadlocking. Rather than |
| 1141 | * trying to be clever about what pages can be locked, |
| 1142 | * avoid the use of lock_page for direct compaction |
| 1143 | * altogether. |
| 1144 | */ |
| 1145 | if (current->flags & PF_MEMALLOC) |
Minchan Kim | 0dabec9 | 2011-10-31 17:06:57 -0700 | [diff] [blame] | 1146 | goto out; |
Mel Gorman | 3e7d344 | 2011-01-13 15:45:56 -0800 | [diff] [blame] | 1147 | |
Douglas Anderson | 4bb6dc7 | 2023-04-28 13:54:38 -0700 | [diff] [blame] | 1148 | /* |
| 1149 | * In "light" mode, we can wait for transient locks (eg |
| 1150 | * inserting a page into the page table), but it's not |
| 1151 | * worth waiting for I/O. |
| 1152 | */ |
| 1153 | if (mode == MIGRATE_SYNC_LIGHT && !folio_test_uptodate(src)) |
| 1154 | goto out; |
| 1155 | |
Matthew Wilcox (Oracle) | 682a71a | 2022-09-02 20:46:46 +0100 | [diff] [blame] | 1156 | folio_lock(src); |
Christoph Lameter | e24f0b8 | 2006-06-23 02:03:51 -0700 | [diff] [blame] | 1157 | } |
Huang Ying | ebe75e4 | 2023-02-13 20:34:42 +0800 | [diff] [blame] | 1158 | locked = true; |
Christoph Lameter | e24f0b8 | 2006-06-23 02:03:51 -0700 | [diff] [blame] | 1159 | |
Matthew Wilcox (Oracle) | 682a71a | 2022-09-02 20:46:46 +0100 | [diff] [blame] | 1160 | if (folio_test_writeback(src)) { |
Andrea Arcangeli | 11bc82d | 2011-03-22 16:33:11 -0700 | [diff] [blame] | 1161 | /* |
Jianguo Wu | fed5b64 | 2013-04-29 15:07:58 -0700 | [diff] [blame] | 1162 | * Only in the case of a full synchronous migration is it |
Mel Gorman | a6bc32b | 2012-01-12 17:19:43 -0800 | [diff] [blame] | 1163 | * necessary to wait for PageWriteback. In the async case, |
| 1164 | * the retry loop is too short and in the sync-light case, |
| 1165 | * the overhead of stalling is too much |
Andrea Arcangeli | 11bc82d | 2011-03-22 16:33:11 -0700 | [diff] [blame] | 1166 | */ |
Jérôme Glisse | 2916ecc | 2017-09-08 16:12:06 -0700 | [diff] [blame] | 1167 | switch (mode) { |
| 1168 | case MIGRATE_SYNC: |
| 1169 | case MIGRATE_SYNC_NO_COPY: |
| 1170 | break; |
| 1171 | default: |
Andrea Arcangeli | 11bc82d | 2011-03-22 16:33:11 -0700 | [diff] [blame] | 1172 | rc = -EBUSY; |
Huang Ying | ebe75e4 | 2023-02-13 20:34:42 +0800 | [diff] [blame] | 1173 | goto out; |
Andrea Arcangeli | 11bc82d | 2011-03-22 16:33:11 -0700 | [diff] [blame] | 1174 | } |
Matthew Wilcox (Oracle) | 682a71a | 2022-09-02 20:46:46 +0100 | [diff] [blame] | 1175 | folio_wait_writeback(src); |
Christoph Lameter | e24f0b8 | 2006-06-23 02:03:51 -0700 | [diff] [blame] | 1176 | } |
Hugh Dickins | 03f15c8 | 2015-11-05 18:49:56 -0800 | [diff] [blame] | 1177 | |
Christoph Lameter | e24f0b8 | 2006-06-23 02:03:51 -0700 | [diff] [blame] | 1178 | /* |
Matthew Wilcox (Oracle) | 682a71a | 2022-09-02 20:46:46 +0100 | [diff] [blame] | 1179 | * By try_to_migrate(), src->mapcount goes down to 0 here. In this case, |
| 1180 | * we cannot notice that anon_vma is freed while we migrate a page. |
Hugh Dickins | 1ce82b6 | 2011-01-13 15:47:30 -0800 | [diff] [blame] | 1181 | * This get_anon_vma() delays freeing anon_vma pointer until the end |
KAMEZAWA Hiroyuki | dc386d4 | 2007-07-26 10:41:07 -0700 | [diff] [blame] | 1182 | * of migration. File cache pages are no problem because of page_lock() |
KAMEZAWA Hiroyuki | 989f89c | 2007-08-30 23:56:21 -0700 | [diff] [blame] | 1183 | * File Caches may use write_page() or lock_page() in migration, then, |
| 1184 | * just care Anon page here. |
Hugh Dickins | 03f15c8 | 2015-11-05 18:49:56 -0800 | [diff] [blame] | 1185 | * |
Matthew Wilcox (Oracle) | 29eea9b | 2022-09-02 20:46:50 +0100 | [diff] [blame] | 1186 | * Only folio_get_anon_vma() understands the subtleties of |
Hugh Dickins | 03f15c8 | 2015-11-05 18:49:56 -0800 | [diff] [blame] | 1187 | * getting a hold on an anon_vma from outside one of its mms. |
| 1188 | * But if we cannot get anon_vma, then we won't need it anyway, |
| 1189 | * because that implies that the anon page is no longer mapped |
| 1190 | * (and cannot be remapped so long as we hold the page lock). |
Christoph Lameter | e24f0b8 | 2006-06-23 02:03:51 -0700 | [diff] [blame] | 1191 | */ |
Matthew Wilcox (Oracle) | 682a71a | 2022-09-02 20:46:46 +0100 | [diff] [blame] | 1192 | if (folio_test_anon(src) && !folio_test_ksm(src)) |
Matthew Wilcox (Oracle) | 29eea9b | 2022-09-02 20:46:50 +0100 | [diff] [blame] | 1193 | anon_vma = folio_get_anon_vma(src); |
Shaohua Li | 62e1c55 | 2008-02-04 22:29:33 -0800 | [diff] [blame] | 1194 | |
Hugh Dickins | 7db7671 | 2015-11-05 18:49:49 -0800 | [diff] [blame] | 1195 | /* |
| 1196 | * Block others from accessing the new page when we get around to |
| 1197 | * establishing additional references. We are usually the only one |
Matthew Wilcox (Oracle) | 682a71a | 2022-09-02 20:46:46 +0100 | [diff] [blame] | 1198 | * holding a reference to dst at this point. We used to have a BUG |
| 1199 | * here if folio_trylock(dst) fails, but would like to allow for |
| 1200 | * cases where there might be a race with the previous use of dst. |
Hugh Dickins | 7db7671 | 2015-11-05 18:49:49 -0800 | [diff] [blame] | 1201 | * This is much like races on refcount of oldpage: just don't BUG(). |
| 1202 | */ |
Matthew Wilcox (Oracle) | 682a71a | 2022-09-02 20:46:46 +0100 | [diff] [blame] | 1203 | if (unlikely(!folio_trylock(dst))) |
Huang Ying | ebe75e4 | 2023-02-13 20:34:42 +0800 | [diff] [blame] | 1204 | goto out; |
| 1205 | dst_locked = true; |
Hugh Dickins | 7db7671 | 2015-11-05 18:49:49 -0800 | [diff] [blame] | 1206 | |
Minchan Kim | bda807d | 2016-07-26 15:23:05 -0700 | [diff] [blame] | 1207 | if (unlikely(!is_lru)) { |
Huang Ying | 64c8902 | 2023-02-13 20:34:39 +0800 | [diff] [blame] | 1208 | __migrate_folio_record(dst, page_was_mapped, anon_vma); |
| 1209 | return MIGRATEPAGE_UNMAP; |
Minchan Kim | bda807d | 2016-07-26 15:23:05 -0700 | [diff] [blame] | 1210 | } |
| 1211 | |
KAMEZAWA Hiroyuki | dc386d4 | 2007-07-26 10:41:07 -0700 | [diff] [blame] | 1212 | /* |
Shaohua Li | 62e1c55 | 2008-02-04 22:29:33 -0800 | [diff] [blame] | 1213 | * Corner case handling: |
| 1214 | * 1. When a new swap-cache page is read into, it is added to the LRU |
| 1215 | * and treated as swapcache but it has no rmap yet. |
Matthew Wilcox (Oracle) | 682a71a | 2022-09-02 20:46:46 +0100 | [diff] [blame] | 1216 | * Calling try_to_unmap() against a src->mapping==NULL page will |
Shaohua Li | 62e1c55 | 2008-02-04 22:29:33 -0800 | [diff] [blame] | 1217 | * trigger a BUG. So handle it here. |
Yang Shi | d12b895 | 2020-12-14 19:13:02 -0800 | [diff] [blame] | 1218 | * 2. An orphaned page (see truncate_cleanup_page) might have |
Shaohua Li | 62e1c55 | 2008-02-04 22:29:33 -0800 | [diff] [blame] | 1219 | * fs-private metadata. The page can be picked up due to memory |
| 1220 | * offlining. Everywhere else except page reclaim, the page is |
| 1221 | * invisible to the vm, so the page can not be migrated. So try to |
| 1222 | * free the metadata, so the page can be freed. |
KAMEZAWA Hiroyuki | dc386d4 | 2007-07-26 10:41:07 -0700 | [diff] [blame] | 1223 | */ |
Matthew Wilcox (Oracle) | 682a71a | 2022-09-02 20:46:46 +0100 | [diff] [blame] | 1224 | if (!src->mapping) { |
| 1225 | if (folio_test_private(src)) { |
| 1226 | try_to_free_buffers(src); |
Huang Ying | ebe75e4 | 2023-02-13 20:34:42 +0800 | [diff] [blame] | 1227 | goto out; |
Shaohua Li | 62e1c55 | 2008-02-04 22:29:33 -0800 | [diff] [blame] | 1228 | } |
Matthew Wilcox (Oracle) | 682a71a | 2022-09-02 20:46:46 +0100 | [diff] [blame] | 1229 | } else if (folio_mapped(src)) { |
Hugh Dickins | 7db7671 | 2015-11-05 18:49:49 -0800 | [diff] [blame] | 1230 | /* Establish migration ptes */ |
Matthew Wilcox (Oracle) | 682a71a | 2022-09-02 20:46:46 +0100 | [diff] [blame] | 1231 | VM_BUG_ON_FOLIO(folio_test_anon(src) && |
| 1232 | !folio_test_ksm(src) && !anon_vma, src); |
Huang Ying | fb3592c | 2023-03-03 11:01:53 +0800 | [diff] [blame] | 1233 | try_to_migrate(src, mode == MIGRATE_ASYNC ? TTU_BATCH_FLUSH : 0); |
Huang Ying | 64c8902 | 2023-02-13 20:34:39 +0800 | [diff] [blame] | 1234 | page_was_mapped = 1; |
Hugh Dickins | 2ebba6b | 2014-12-12 16:56:19 -0800 | [diff] [blame] | 1235 | } |
KAMEZAWA Hiroyuki | dc386d4 | 2007-07-26 10:41:07 -0700 | [diff] [blame] | 1236 | |
Huang Ying | 64c8902 | 2023-02-13 20:34:39 +0800 | [diff] [blame] | 1237 | if (!folio_mapped(src)) { |
| 1238 | __migrate_folio_record(dst, page_was_mapped, anon_vma); |
| 1239 | return MIGRATEPAGE_UNMAP; |
| 1240 | } |
| 1241 | |
Huang Ying | 64c8902 | 2023-02-13 20:34:39 +0800 | [diff] [blame] | 1242 | out: |
Huang Ying | 80562ba | 2023-02-13 20:34:41 +0800 | [diff] [blame] | 1243 | /* |
| 1244 | * A folio that has not been unmapped will be restored to |
| 1245 | * right list unless we want to retry. |
| 1246 | */ |
Huang Ying | fb3592c | 2023-03-03 11:01:53 +0800 | [diff] [blame] | 1247 | if (rc == -EAGAIN) |
Huang Ying | ebe75e4 | 2023-02-13 20:34:42 +0800 | [diff] [blame] | 1248 | ret = NULL; |
Huang Ying | 80562ba | 2023-02-13 20:34:41 +0800 | [diff] [blame] | 1249 | |
Huang Ying | ebe75e4 | 2023-02-13 20:34:42 +0800 | [diff] [blame] | 1250 | migrate_folio_undo_src(src, page_was_mapped, anon_vma, locked, ret); |
Matthew Wilcox (Oracle) | 4e096ae | 2023-05-13 01:11:01 +0100 | [diff] [blame] | 1251 | migrate_folio_undo_dst(dst, dst_locked, put_new_folio, private); |
Huang Ying | 80562ba | 2023-02-13 20:34:41 +0800 | [diff] [blame] | 1252 | |
| 1253 | return rc; |
| 1254 | } |
| 1255 | |
Huang Ying | ebe75e4 | 2023-02-13 20:34:42 +0800 | [diff] [blame] | 1256 | /* Migrate the folio to the newly allocated folio in dst. */ |
Matthew Wilcox (Oracle) | 4e096ae | 2023-05-13 01:11:01 +0100 | [diff] [blame] | 1257 | static int migrate_folio_move(free_folio_t put_new_folio, unsigned long private, |
Huang Ying | ebe75e4 | 2023-02-13 20:34:42 +0800 | [diff] [blame] | 1258 | struct folio *src, struct folio *dst, |
| 1259 | enum migrate_mode mode, enum migrate_reason reason, |
| 1260 | struct list_head *ret) |
Huang Ying | 64c8902 | 2023-02-13 20:34:39 +0800 | [diff] [blame] | 1261 | { |
| 1262 | int rc; |
| 1263 | int page_was_mapped = 0; |
| 1264 | struct anon_vma *anon_vma = NULL; |
| 1265 | bool is_lru = !__PageMovable(&src->page); |
Huang Ying | 5dfab10 | 2023-02-13 20:34:40 +0800 | [diff] [blame] | 1266 | struct list_head *prev; |
Huang Ying | 64c8902 | 2023-02-13 20:34:39 +0800 | [diff] [blame] | 1267 | |
| 1268 | __migrate_folio_extract(dst, &page_was_mapped, &anon_vma); |
Huang Ying | 5dfab10 | 2023-02-13 20:34:40 +0800 | [diff] [blame] | 1269 | prev = dst->lru.prev; |
| 1270 | list_del(&dst->lru); |
Huang Ying | 64c8902 | 2023-02-13 20:34:39 +0800 | [diff] [blame] | 1271 | |
| 1272 | rc = move_to_new_folio(dst, src, mode); |
Huang Ying | ebe75e4 | 2023-02-13 20:34:42 +0800 | [diff] [blame] | 1273 | if (rc) |
| 1274 | goto out; |
Huang Ying | 5dfab10 | 2023-02-13 20:34:40 +0800 | [diff] [blame] | 1275 | |
Huang Ying | 64c8902 | 2023-02-13 20:34:39 +0800 | [diff] [blame] | 1276 | if (unlikely(!is_lru)) |
| 1277 | goto out_unlock_both; |
Christoph Lameter | e24f0b8 | 2006-06-23 02:03:51 -0700 | [diff] [blame] | 1278 | |
Hugh Dickins | c3096e6 | 2022-02-14 18:33:17 -0800 | [diff] [blame] | 1279 | /* |
Matthew Wilcox (Oracle) | 682a71a | 2022-09-02 20:46:46 +0100 | [diff] [blame] | 1280 | * When successful, push dst to LRU immediately: so that if it |
Hugh Dickins | c3096e6 | 2022-02-14 18:33:17 -0800 | [diff] [blame] | 1281 | * turns out to be an mlocked page, remove_migration_ptes() will |
Matthew Wilcox (Oracle) | 682a71a | 2022-09-02 20:46:46 +0100 | [diff] [blame] | 1282 | * automatically build up the correct dst->mlock_count for it. |
Hugh Dickins | c3096e6 | 2022-02-14 18:33:17 -0800 | [diff] [blame] | 1283 | * |
| 1284 | * We would like to do something similar for the old page, when |
| 1285 | * unsuccessful, and other cases when a page has been temporarily |
| 1286 | * isolated from the unevictable LRU: but this case is the easiest. |
| 1287 | */ |
Huang Ying | ebe75e4 | 2023-02-13 20:34:42 +0800 | [diff] [blame] | 1288 | folio_add_lru(dst); |
| 1289 | if (page_was_mapped) |
| 1290 | lru_add_drain(); |
Hugh Dickins | c3096e6 | 2022-02-14 18:33:17 -0800 | [diff] [blame] | 1291 | |
Hugh Dickins | 5c3f9a6 | 2015-11-05 18:49:53 -0800 | [diff] [blame] | 1292 | if (page_was_mapped) |
Huang Ying | ebe75e4 | 2023-02-13 20:34:42 +0800 | [diff] [blame] | 1293 | remove_migration_ptes(src, dst, false); |
Mel Gorman | 3f6c827 | 2010-05-24 14:32:17 -0700 | [diff] [blame] | 1294 | |
Hugh Dickins | 7db7671 | 2015-11-05 18:49:49 -0800 | [diff] [blame] | 1295 | out_unlock_both: |
Matthew Wilcox (Oracle) | 682a71a | 2022-09-02 20:46:46 +0100 | [diff] [blame] | 1296 | folio_unlock(dst); |
Huang Ying | ebe75e4 | 2023-02-13 20:34:42 +0800 | [diff] [blame] | 1297 | set_page_owner_migrate_reason(&dst->page, reason); |
Minchan Kim | c6c919e | 2016-07-26 15:23:02 -0700 | [diff] [blame] | 1298 | /* |
Matthew Wilcox (Oracle) | 682a71a | 2022-09-02 20:46:46 +0100 | [diff] [blame] | 1299 | * If migration is successful, decrease refcount of dst, |
Minchan Kim | c6c919e | 2016-07-26 15:23:02 -0700 | [diff] [blame] | 1300 | * which will not free the page because new page owner increased |
Hugh Dickins | c3096e6 | 2022-02-14 18:33:17 -0800 | [diff] [blame] | 1301 | * refcounter. |
Minchan Kim | c6c919e | 2016-07-26 15:23:02 -0700 | [diff] [blame] | 1302 | */ |
Huang Ying | ebe75e4 | 2023-02-13 20:34:42 +0800 | [diff] [blame] | 1303 | folio_put(dst); |
David Rientjes | 68711a7 | 2014-06-04 16:08:25 -0700 | [diff] [blame] | 1304 | |
Christoph Lameter | 95a402c | 2006-06-23 02:03:53 -0700 | [diff] [blame] | 1305 | /* |
Huang Ying | ebe75e4 | 2023-02-13 20:34:42 +0800 | [diff] [blame] | 1306 | * A folio that has been migrated has all references removed |
| 1307 | * and will be freed. |
Christoph Lameter | 95a402c | 2006-06-23 02:03:53 -0700 | [diff] [blame] | 1308 | */ |
Huang Ying | ebe75e4 | 2023-02-13 20:34:42 +0800 | [diff] [blame] | 1309 | list_del(&src->lru); |
| 1310 | /* Drop an anon_vma reference if we took one */ |
| 1311 | if (anon_vma) |
| 1312 | put_anon_vma(anon_vma); |
| 1313 | folio_unlock(src); |
| 1314 | migrate_folio_done(src, reason); |
Yang Shi | dd4ae78 | 2020-12-14 19:13:06 -0800 | [diff] [blame] | 1315 | |
Huang Ying | ebe75e4 | 2023-02-13 20:34:42 +0800 | [diff] [blame] | 1316 | return rc; |
| 1317 | out: |
| 1318 | /* |
| 1319 | * A folio that has not been migrated will be restored to |
| 1320 | * right list unless we want to retry. |
| 1321 | */ |
| 1322 | if (rc == -EAGAIN) { |
| 1323 | list_add(&dst->lru, prev); |
| 1324 | __migrate_folio_record(dst, page_was_mapped, anon_vma); |
| 1325 | return rc; |
Minchan Kim | c6c919e | 2016-07-26 15:23:02 -0700 | [diff] [blame] | 1326 | } |
David Rientjes | 68711a7 | 2014-06-04 16:08:25 -0700 | [diff] [blame] | 1327 | |
Huang Ying | ebe75e4 | 2023-02-13 20:34:42 +0800 | [diff] [blame] | 1328 | migrate_folio_undo_src(src, page_was_mapped, anon_vma, true, ret); |
Matthew Wilcox (Oracle) | 4e096ae | 2023-05-13 01:11:01 +0100 | [diff] [blame] | 1329 | migrate_folio_undo_dst(dst, true, put_new_folio, private); |
Huang Ying | ebe75e4 | 2023-02-13 20:34:42 +0800 | [diff] [blame] | 1330 | |
Christoph Lameter | e24f0b8 | 2006-06-23 02:03:51 -0700 | [diff] [blame] | 1331 | return rc; |
| 1332 | } |
| 1333 | |
| 1334 | /* |
Naoya Horiguchi | 290408d | 2010-09-08 10:19:35 +0900 | [diff] [blame] | 1335 | * Counterpart of unmap_and_move_page() for hugepage migration. |
| 1336 | * |
| 1337 | * This function doesn't wait the completion of hugepage I/O |
| 1338 | * because there is no race between I/O and migration for hugepage. |
| 1339 | * Note that currently hugepage I/O occurs only in direct I/O |
| 1340 | * where no lock is held and PG_writeback is irrelevant, |
| 1341 | * and writeback status of all subpages are counted in the reference |
| 1342 | * count of the head page (i.e. if all subpages of a 2MB hugepage are |
| 1343 | * under direct I/O, the reference of the head page is 512 and a bit more.) |
| 1344 | * This means that when we try to migrate hugepage whose subpages are |
| 1345 | * doing direct I/O, some references remain after try_to_unmap() and |
| 1346 | * hugepage migration fails without data corruption. |
| 1347 | * |
| 1348 | * There is also no race when direct I/O is issued on the page under migration, |
| 1349 | * because then pte is replaced with migration swap entry and direct I/O code |
| 1350 | * will wait in the page fault for migration to complete. |
| 1351 | */ |
Matthew Wilcox (Oracle) | 4e096ae | 2023-05-13 01:11:01 +0100 | [diff] [blame] | 1352 | static int unmap_and_move_huge_page(new_folio_t get_new_folio, |
| 1353 | free_folio_t put_new_folio, unsigned long private, |
| 1354 | struct folio *src, int force, enum migrate_mode mode, |
| 1355 | int reason, struct list_head *ret) |
Naoya Horiguchi | 290408d | 2010-09-08 10:19:35 +0900 | [diff] [blame] | 1356 | { |
Matthew Wilcox (Oracle) | 4e096ae | 2023-05-13 01:11:01 +0100 | [diff] [blame] | 1357 | struct folio *dst; |
Hugh Dickins | 2def742 | 2015-11-05 18:49:46 -0800 | [diff] [blame] | 1358 | int rc = -EAGAIN; |
Hugh Dickins | 2ebba6b | 2014-12-12 16:56:19 -0800 | [diff] [blame] | 1359 | int page_was_mapped = 0; |
Naoya Horiguchi | 290408d | 2010-09-08 10:19:35 +0900 | [diff] [blame] | 1360 | struct anon_vma *anon_vma = NULL; |
Mike Kravetz | c0d0381 | 2020-04-01 21:11:05 -0700 | [diff] [blame] | 1361 | struct address_space *mapping = NULL; |
Naoya Horiguchi | 290408d | 2010-09-08 10:19:35 +0900 | [diff] [blame] | 1362 | |
Matthew Wilcox (Oracle) | c33db29 | 2022-09-02 20:46:47 +0100 | [diff] [blame] | 1363 | if (folio_ref_count(src) == 1) { |
Muchun Song | 71a64f6 | 2021-02-04 18:32:17 -0800 | [diff] [blame] | 1364 | /* page was freed from under us. So we are done. */ |
Sidhartha Kumar | ea8e72f | 2023-01-25 09:05:32 -0800 | [diff] [blame] | 1365 | folio_putback_active_hugetlb(src); |
Muchun Song | 71a64f6 | 2021-02-04 18:32:17 -0800 | [diff] [blame] | 1366 | return MIGRATEPAGE_SUCCESS; |
| 1367 | } |
| 1368 | |
Matthew Wilcox (Oracle) | 4e096ae | 2023-05-13 01:11:01 +0100 | [diff] [blame] | 1369 | dst = get_new_folio(src, private); |
| 1370 | if (!dst) |
Naoya Horiguchi | 290408d | 2010-09-08 10:19:35 +0900 | [diff] [blame] | 1371 | return -ENOMEM; |
| 1372 | |
Matthew Wilcox (Oracle) | c33db29 | 2022-09-02 20:46:47 +0100 | [diff] [blame] | 1373 | if (!folio_trylock(src)) { |
Jérôme Glisse | 2916ecc | 2017-09-08 16:12:06 -0700 | [diff] [blame] | 1374 | if (!force) |
Naoya Horiguchi | 290408d | 2010-09-08 10:19:35 +0900 | [diff] [blame] | 1375 | goto out; |
Jérôme Glisse | 2916ecc | 2017-09-08 16:12:06 -0700 | [diff] [blame] | 1376 | switch (mode) { |
| 1377 | case MIGRATE_SYNC: |
| 1378 | case MIGRATE_SYNC_NO_COPY: |
| 1379 | break; |
| 1380 | default: |
| 1381 | goto out; |
| 1382 | } |
Matthew Wilcox (Oracle) | c33db29 | 2022-09-02 20:46:47 +0100 | [diff] [blame] | 1383 | folio_lock(src); |
Naoya Horiguchi | 290408d | 2010-09-08 10:19:35 +0900 | [diff] [blame] | 1384 | } |
| 1385 | |
Mike Kravetz | cb6acd0 | 2019-02-28 16:22:02 -0800 | [diff] [blame] | 1386 | /* |
| 1387 | * Check for pages which are in the process of being freed. Without |
Matthew Wilcox (Oracle) | c33db29 | 2022-09-02 20:46:47 +0100 | [diff] [blame] | 1388 | * folio_mapping() set, hugetlbfs specific move page routine will not |
Mike Kravetz | cb6acd0 | 2019-02-28 16:22:02 -0800 | [diff] [blame] | 1389 | * be called and we could leak usage counts for subpools. |
| 1390 | */ |
Sidhartha Kumar | 345c62d | 2022-11-01 15:30:59 -0700 | [diff] [blame] | 1391 | if (hugetlb_folio_subpool(src) && !folio_mapping(src)) { |
Mike Kravetz | cb6acd0 | 2019-02-28 16:22:02 -0800 | [diff] [blame] | 1392 | rc = -EBUSY; |
| 1393 | goto out_unlock; |
| 1394 | } |
| 1395 | |
Matthew Wilcox (Oracle) | c33db29 | 2022-09-02 20:46:47 +0100 | [diff] [blame] | 1396 | if (folio_test_anon(src)) |
Matthew Wilcox (Oracle) | 29eea9b | 2022-09-02 20:46:50 +0100 | [diff] [blame] | 1397 | anon_vma = folio_get_anon_vma(src); |
Naoya Horiguchi | 290408d | 2010-09-08 10:19:35 +0900 | [diff] [blame] | 1398 | |
Matthew Wilcox (Oracle) | c33db29 | 2022-09-02 20:46:47 +0100 | [diff] [blame] | 1399 | if (unlikely(!folio_trylock(dst))) |
Hugh Dickins | 7db7671 | 2015-11-05 18:49:49 -0800 | [diff] [blame] | 1400 | goto put_anon; |
| 1401 | |
Matthew Wilcox (Oracle) | c33db29 | 2022-09-02 20:46:47 +0100 | [diff] [blame] | 1402 | if (folio_mapped(src)) { |
Alistair Popple | a98a2f0 | 2021-06-30 18:54:16 -0700 | [diff] [blame] | 1403 | enum ttu_flags ttu = 0; |
Mike Kravetz | c0d0381 | 2020-04-01 21:11:05 -0700 | [diff] [blame] | 1404 | |
Matthew Wilcox (Oracle) | c33db29 | 2022-09-02 20:46:47 +0100 | [diff] [blame] | 1405 | if (!folio_test_anon(src)) { |
Mike Kravetz | 336bf30 | 2020-11-13 22:52:16 -0800 | [diff] [blame] | 1406 | /* |
| 1407 | * In shared mappings, try_to_unmap could potentially |
| 1408 | * call huge_pmd_unshare. Because of this, take |
| 1409 | * semaphore in write mode here and set TTU_RMAP_LOCKED |
| 1410 | * to let lower levels know we have taken the lock. |
| 1411 | */ |
Matthew Wilcox (Oracle) | 4e096ae | 2023-05-13 01:11:01 +0100 | [diff] [blame] | 1412 | mapping = hugetlb_page_mapping_lock_write(&src->page); |
Mike Kravetz | 336bf30 | 2020-11-13 22:52:16 -0800 | [diff] [blame] | 1413 | if (unlikely(!mapping)) |
| 1414 | goto unlock_put_anon; |
| 1415 | |
Miaohe Lin | 5202978 | 2022-04-28 23:16:07 -0700 | [diff] [blame] | 1416 | ttu = TTU_RMAP_LOCKED; |
Mike Kravetz | 336bf30 | 2020-11-13 22:52:16 -0800 | [diff] [blame] | 1417 | } |
| 1418 | |
Matthew Wilcox (Oracle) | 4b8554c | 2022-01-28 14:29:43 -0500 | [diff] [blame] | 1419 | try_to_migrate(src, ttu); |
Hugh Dickins | 2ebba6b | 2014-12-12 16:56:19 -0800 | [diff] [blame] | 1420 | page_was_mapped = 1; |
Mike Kravetz | 336bf30 | 2020-11-13 22:52:16 -0800 | [diff] [blame] | 1421 | |
Miaohe Lin | 5202978 | 2022-04-28 23:16:07 -0700 | [diff] [blame] | 1422 | if (ttu & TTU_RMAP_LOCKED) |
Mike Kravetz | 336bf30 | 2020-11-13 22:52:16 -0800 | [diff] [blame] | 1423 | i_mmap_unlock_write(mapping); |
Hugh Dickins | 2ebba6b | 2014-12-12 16:56:19 -0800 | [diff] [blame] | 1424 | } |
Naoya Horiguchi | 290408d | 2010-09-08 10:19:35 +0900 | [diff] [blame] | 1425 | |
Matthew Wilcox (Oracle) | c33db29 | 2022-09-02 20:46:47 +0100 | [diff] [blame] | 1426 | if (!folio_mapped(src)) |
Matthew Wilcox (Oracle) | e7e3ffe | 2022-05-12 20:23:05 -0700 | [diff] [blame] | 1427 | rc = move_to_new_folio(dst, src, mode); |
Naoya Horiguchi | 290408d | 2010-09-08 10:19:35 +0900 | [diff] [blame] | 1428 | |
Mike Kravetz | 336bf30 | 2020-11-13 22:52:16 -0800 | [diff] [blame] | 1429 | if (page_was_mapped) |
Matthew Wilcox (Oracle) | 4eecb8b | 2022-01-28 23:32:59 -0500 | [diff] [blame] | 1430 | remove_migration_ptes(src, |
| 1431 | rc == MIGRATEPAGE_SUCCESS ? dst : src, false); |
Naoya Horiguchi | 290408d | 2010-09-08 10:19:35 +0900 | [diff] [blame] | 1432 | |
Mike Kravetz | c0d0381 | 2020-04-01 21:11:05 -0700 | [diff] [blame] | 1433 | unlock_put_anon: |
Matthew Wilcox (Oracle) | c33db29 | 2022-09-02 20:46:47 +0100 | [diff] [blame] | 1434 | folio_unlock(dst); |
Hugh Dickins | 7db7671 | 2015-11-05 18:49:49 -0800 | [diff] [blame] | 1435 | |
| 1436 | put_anon: |
Hugh Dickins | fd4a466 | 2011-01-13 15:47:31 -0800 | [diff] [blame] | 1437 | if (anon_vma) |
Peter Zijlstra | 9e60109 | 2011-03-22 16:32:46 -0700 | [diff] [blame] | 1438 | put_anon_vma(anon_vma); |
Aneesh Kumar K.V | 8e6ac7f | 2012-07-31 16:42:27 -0700 | [diff] [blame] | 1439 | |
Hugh Dickins | 2def742 | 2015-11-05 18:49:46 -0800 | [diff] [blame] | 1440 | if (rc == MIGRATEPAGE_SUCCESS) { |
Sidhartha Kumar | 345c62d | 2022-11-01 15:30:59 -0700 | [diff] [blame] | 1441 | move_hugetlb_state(src, dst, reason); |
Matthew Wilcox (Oracle) | 4e096ae | 2023-05-13 01:11:01 +0100 | [diff] [blame] | 1442 | put_new_folio = NULL; |
Hugh Dickins | 2def742 | 2015-11-05 18:49:46 -0800 | [diff] [blame] | 1443 | } |
Aneesh Kumar K.V | 8e6ac7f | 2012-07-31 16:42:27 -0700 | [diff] [blame] | 1444 | |
Mike Kravetz | cb6acd0 | 2019-02-28 16:22:02 -0800 | [diff] [blame] | 1445 | out_unlock: |
Matthew Wilcox (Oracle) | c33db29 | 2022-09-02 20:46:47 +0100 | [diff] [blame] | 1446 | folio_unlock(src); |
Hillf Danton | 0976133 | 2011-12-08 14:34:20 -0800 | [diff] [blame] | 1447 | out: |
Yang Shi | dd4ae78 | 2020-12-14 19:13:06 -0800 | [diff] [blame] | 1448 | if (rc == MIGRATEPAGE_SUCCESS) |
Sidhartha Kumar | ea8e72f | 2023-01-25 09:05:32 -0800 | [diff] [blame] | 1449 | folio_putback_active_hugetlb(src); |
Miaohe Lin | a04840c | 2021-05-04 18:37:07 -0700 | [diff] [blame] | 1450 | else if (rc != -EAGAIN) |
Matthew Wilcox (Oracle) | c33db29 | 2022-09-02 20:46:47 +0100 | [diff] [blame] | 1451 | list_move_tail(&src->lru, ret); |
David Rientjes | 68711a7 | 2014-06-04 16:08:25 -0700 | [diff] [blame] | 1452 | |
| 1453 | /* |
| 1454 | * If migration was not successful and there's a freeing callback, use |
| 1455 | * it. Otherwise, put_page() will drop the reference grabbed during |
| 1456 | * isolation. |
| 1457 | */ |
Matthew Wilcox (Oracle) | 4e096ae | 2023-05-13 01:11:01 +0100 | [diff] [blame] | 1458 | if (put_new_folio) |
| 1459 | put_new_folio(dst, private); |
David Rientjes | 68711a7 | 2014-06-04 16:08:25 -0700 | [diff] [blame] | 1460 | else |
Sidhartha Kumar | ea8e72f | 2023-01-25 09:05:32 -0800 | [diff] [blame] | 1461 | folio_putback_active_hugetlb(dst); |
David Rientjes | 68711a7 | 2014-06-04 16:08:25 -0700 | [diff] [blame] | 1462 | |
Naoya Horiguchi | 290408d | 2010-09-08 10:19:35 +0900 | [diff] [blame] | 1463 | return rc; |
| 1464 | } |
| 1465 | |
Huang Ying | eaec4e6 | 2022-11-09 09:23:48 +0800 | [diff] [blame] | 1466 | static inline int try_split_folio(struct folio *folio, struct list_head *split_folios) |
Yang Shi | d532e2e | 2020-12-14 19:13:16 -0800 | [diff] [blame] | 1467 | { |
Huang Ying | 9c62ff0 | 2022-08-17 16:14:02 +0800 | [diff] [blame] | 1468 | int rc; |
Yang Shi | d532e2e | 2020-12-14 19:13:16 -0800 | [diff] [blame] | 1469 | |
Huang Ying | eaec4e6 | 2022-11-09 09:23:48 +0800 | [diff] [blame] | 1470 | folio_lock(folio); |
| 1471 | rc = split_folio_to_list(folio, split_folios); |
| 1472 | folio_unlock(folio); |
Huang Ying | e6fa8a7 | 2022-08-17 16:14:06 +0800 | [diff] [blame] | 1473 | if (!rc) |
Huang Ying | eaec4e6 | 2022-11-09 09:23:48 +0800 | [diff] [blame] | 1474 | list_move_tail(&folio->lru, split_folios); |
Yang Shi | d532e2e | 2020-12-14 19:13:16 -0800 | [diff] [blame] | 1475 | |
| 1476 | return rc; |
| 1477 | } |
| 1478 | |
Huang Ying | 42012e0 | 2023-02-13 20:34:38 +0800 | [diff] [blame] | 1479 | #ifdef CONFIG_TRANSPARENT_HUGEPAGE |
| 1480 | #define NR_MAX_BATCHED_MIGRATION HPAGE_PMD_NR |
| 1481 | #else |
| 1482 | #define NR_MAX_BATCHED_MIGRATION 512 |
| 1483 | #endif |
Huang Ying | e5bfff8b | 2023-02-13 20:34:37 +0800 | [diff] [blame] | 1484 | #define NR_MAX_MIGRATE_PAGES_RETRY 10 |
Huang Ying | 2ef7dbb | 2023-03-03 11:01:55 +0800 | [diff] [blame] | 1485 | #define NR_MAX_MIGRATE_ASYNC_RETRY 3 |
| 1486 | #define NR_MAX_MIGRATE_SYNC_RETRY \ |
| 1487 | (NR_MAX_MIGRATE_PAGES_RETRY - NR_MAX_MIGRATE_ASYNC_RETRY) |
Huang Ying | e5bfff8b | 2023-02-13 20:34:37 +0800 | [diff] [blame] | 1488 | |
Huang Ying | 5b85593 | 2023-02-13 20:34:36 +0800 | [diff] [blame] | 1489 | struct migrate_pages_stats { |
| 1490 | int nr_succeeded; /* Normal and large folios migrated successfully, in |
| 1491 | units of base pages */ |
| 1492 | int nr_failed_pages; /* Normal and large folios failed to be migrated, in |
| 1493 | units of base pages. Untried folios aren't counted */ |
| 1494 | int nr_thp_succeeded; /* THP migrated successfully */ |
| 1495 | int nr_thp_failed; /* THP failed to be migrated */ |
| 1496 | int nr_thp_split; /* THP split before migrating */ |
| 1497 | }; |
| 1498 | |
Naoya Horiguchi | 290408d | 2010-09-08 10:19:35 +0900 | [diff] [blame] | 1499 | /* |
Huang Ying | e5bfff8b | 2023-02-13 20:34:37 +0800 | [diff] [blame] | 1500 | * Returns the number of hugetlb folios that were not migrated, or an error code |
| 1501 | * after NR_MAX_MIGRATE_PAGES_RETRY attempts or if no hugetlb folios are movable |
| 1502 | * any more because the list has become empty or no retryable hugetlb folios |
| 1503 | * exist any more. It is caller's responsibility to call putback_movable_pages() |
| 1504 | * only if ret != 0. |
| 1505 | */ |
Matthew Wilcox (Oracle) | 4e096ae | 2023-05-13 01:11:01 +0100 | [diff] [blame] | 1506 | static int migrate_hugetlbs(struct list_head *from, new_folio_t get_new_folio, |
| 1507 | free_folio_t put_new_folio, unsigned long private, |
Huang Ying | e5bfff8b | 2023-02-13 20:34:37 +0800 | [diff] [blame] | 1508 | enum migrate_mode mode, int reason, |
| 1509 | struct migrate_pages_stats *stats, |
| 1510 | struct list_head *ret_folios) |
| 1511 | { |
| 1512 | int retry = 1; |
| 1513 | int nr_failed = 0; |
| 1514 | int nr_retry_pages = 0; |
| 1515 | int pass = 0; |
| 1516 | struct folio *folio, *folio2; |
| 1517 | int rc, nr_pages; |
| 1518 | |
| 1519 | for (pass = 0; pass < NR_MAX_MIGRATE_PAGES_RETRY && retry; pass++) { |
| 1520 | retry = 0; |
| 1521 | nr_retry_pages = 0; |
| 1522 | |
| 1523 | list_for_each_entry_safe(folio, folio2, from, lru) { |
| 1524 | if (!folio_test_hugetlb(folio)) |
| 1525 | continue; |
| 1526 | |
| 1527 | nr_pages = folio_nr_pages(folio); |
| 1528 | |
| 1529 | cond_resched(); |
| 1530 | |
Huang Ying | 6f7d760 | 2023-02-13 20:34:44 +0800 | [diff] [blame] | 1531 | /* |
| 1532 | * Migratability of hugepages depends on architectures and |
| 1533 | * their size. This check is necessary because some callers |
| 1534 | * of hugepage migration like soft offline and memory |
| 1535 | * hotremove don't walk through page tables or check whether |
| 1536 | * the hugepage is pmd-based or not before kicking migration. |
| 1537 | */ |
| 1538 | if (!hugepage_migration_supported(folio_hstate(folio))) { |
| 1539 | nr_failed++; |
| 1540 | stats->nr_failed_pages += nr_pages; |
| 1541 | list_move_tail(&folio->lru, ret_folios); |
| 1542 | continue; |
| 1543 | } |
| 1544 | |
Matthew Wilcox (Oracle) | 4e096ae | 2023-05-13 01:11:01 +0100 | [diff] [blame] | 1545 | rc = unmap_and_move_huge_page(get_new_folio, |
| 1546 | put_new_folio, private, |
| 1547 | folio, pass > 2, mode, |
Huang Ying | e5bfff8b | 2023-02-13 20:34:37 +0800 | [diff] [blame] | 1548 | reason, ret_folios); |
| 1549 | /* |
| 1550 | * The rules are: |
| 1551 | * Success: hugetlb folio will be put back |
| 1552 | * -EAGAIN: stay on the from list |
| 1553 | * -ENOMEM: stay on the from list |
Huang Ying | e5bfff8b | 2023-02-13 20:34:37 +0800 | [diff] [blame] | 1554 | * Other errno: put on ret_folios list |
| 1555 | */ |
| 1556 | switch(rc) { |
Huang Ying | e5bfff8b | 2023-02-13 20:34:37 +0800 | [diff] [blame] | 1557 | case -ENOMEM: |
| 1558 | /* |
| 1559 | * When memory is low, don't bother to try to migrate |
| 1560 | * other folios, just exit. |
| 1561 | */ |
| 1562 | stats->nr_failed_pages += nr_pages + nr_retry_pages; |
| 1563 | return -ENOMEM; |
| 1564 | case -EAGAIN: |
| 1565 | retry++; |
| 1566 | nr_retry_pages += nr_pages; |
| 1567 | break; |
| 1568 | case MIGRATEPAGE_SUCCESS: |
| 1569 | stats->nr_succeeded += nr_pages; |
| 1570 | break; |
| 1571 | default: |
| 1572 | /* |
| 1573 | * Permanent failure (-EBUSY, etc.): |
| 1574 | * unlike -EAGAIN case, the failed folio is |
| 1575 | * removed from migration folio list and not |
| 1576 | * retried in the next outer loop. |
| 1577 | */ |
| 1578 | nr_failed++; |
| 1579 | stats->nr_failed_pages += nr_pages; |
| 1580 | break; |
| 1581 | } |
| 1582 | } |
| 1583 | } |
| 1584 | /* |
| 1585 | * nr_failed is number of hugetlb folios failed to be migrated. After |
| 1586 | * NR_MAX_MIGRATE_PAGES_RETRY attempts, give up and count retried hugetlb |
| 1587 | * folios as failed. |
| 1588 | */ |
| 1589 | nr_failed += retry; |
| 1590 | stats->nr_failed_pages += nr_retry_pages; |
| 1591 | |
| 1592 | return nr_failed; |
| 1593 | } |
| 1594 | |
Huang Ying | 5dfab10 | 2023-02-13 20:34:40 +0800 | [diff] [blame] | 1595 | /* |
| 1596 | * migrate_pages_batch() first unmaps folios in the from list as many as |
| 1597 | * possible, then move the unmapped folios. |
Huang Ying | fb3592c | 2023-03-03 11:01:53 +0800 | [diff] [blame] | 1598 | * |
| 1599 | * We only batch migration if mode == MIGRATE_ASYNC to avoid to wait a |
| 1600 | * lock or bit when we have locked more than one folio. Which may cause |
| 1601 | * deadlock (e.g., for loop device). So, if mode != MIGRATE_ASYNC, the |
| 1602 | * length of the from list must be <= 1. |
Huang Ying | 5dfab10 | 2023-02-13 20:34:40 +0800 | [diff] [blame] | 1603 | */ |
Matthew Wilcox (Oracle) | 4e096ae | 2023-05-13 01:11:01 +0100 | [diff] [blame] | 1604 | static int migrate_pages_batch(struct list_head *from, |
| 1605 | new_folio_t get_new_folio, free_folio_t put_new_folio, |
| 1606 | unsigned long private, enum migrate_mode mode, int reason, |
| 1607 | struct list_head *ret_folios, struct list_head *split_folios, |
| 1608 | struct migrate_pages_stats *stats, int nr_pass) |
Huang Ying | 42012e0 | 2023-02-13 20:34:38 +0800 | [diff] [blame] | 1609 | { |
Huang Ying | a21d213 | 2023-03-03 11:01:54 +0800 | [diff] [blame] | 1610 | int retry = 1; |
Huang Ying | 42012e0 | 2023-02-13 20:34:38 +0800 | [diff] [blame] | 1611 | int thp_retry = 1; |
| 1612 | int nr_failed = 0; |
| 1613 | int nr_retry_pages = 0; |
Huang Ying | 42012e0 | 2023-02-13 20:34:38 +0800 | [diff] [blame] | 1614 | int pass = 0; |
Huang Ying | 42012e0 | 2023-02-13 20:34:38 +0800 | [diff] [blame] | 1615 | bool is_thp = false; |
Huang Ying | 5dfab10 | 2023-02-13 20:34:40 +0800 | [diff] [blame] | 1616 | struct folio *folio, *folio2, *dst = NULL, *dst2; |
Huang Ying | a21d213 | 2023-03-03 11:01:54 +0800 | [diff] [blame] | 1617 | int rc, rc_saved = 0, nr_pages; |
Huang Ying | 5dfab10 | 2023-02-13 20:34:40 +0800 | [diff] [blame] | 1618 | LIST_HEAD(unmap_folios); |
| 1619 | LIST_HEAD(dst_folios); |
Huang Ying | 42012e0 | 2023-02-13 20:34:38 +0800 | [diff] [blame] | 1620 | bool nosplit = (reason == MR_NUMA_MISPLACED); |
Huang Ying | 42012e0 | 2023-02-13 20:34:38 +0800 | [diff] [blame] | 1621 | |
Huang Ying | fb3592c | 2023-03-03 11:01:53 +0800 | [diff] [blame] | 1622 | VM_WARN_ON_ONCE(mode != MIGRATE_ASYNC && |
| 1623 | !list_empty(from) && !list_is_singular(from)); |
Huang Ying | a21d213 | 2023-03-03 11:01:54 +0800 | [diff] [blame] | 1624 | |
Huang Ying | 124abce | 2023-05-10 11:18:29 +0800 | [diff] [blame] | 1625 | for (pass = 0; pass < nr_pass && retry; pass++) { |
Huang Ying | 42012e0 | 2023-02-13 20:34:38 +0800 | [diff] [blame] | 1626 | retry = 0; |
Huang Ying | 42012e0 | 2023-02-13 20:34:38 +0800 | [diff] [blame] | 1627 | thp_retry = 0; |
| 1628 | nr_retry_pages = 0; |
| 1629 | |
| 1630 | list_for_each_entry_safe(folio, folio2, from, lru) { |
Huang Ying | 124abce | 2023-05-10 11:18:29 +0800 | [diff] [blame] | 1631 | is_thp = folio_test_large(folio) && folio_test_pmd_mappable(folio); |
Huang Ying | 42012e0 | 2023-02-13 20:34:38 +0800 | [diff] [blame] | 1632 | nr_pages = folio_nr_pages(folio); |
| 1633 | |
| 1634 | cond_resched(); |
| 1635 | |
Huang Ying | 6f7d760 | 2023-02-13 20:34:44 +0800 | [diff] [blame] | 1636 | /* |
| 1637 | * Large folio migration might be unsupported or |
| 1638 | * the allocation might be failed so we should retry |
| 1639 | * on the same folio with the large folio split |
| 1640 | * to normal folios. |
| 1641 | * |
| 1642 | * Split folios are put in split_folios, and |
| 1643 | * we will migrate them after the rest of the |
| 1644 | * list is processed. |
| 1645 | */ |
| 1646 | if (!thp_migration_supported() && is_thp) { |
Huang Ying | 124abce | 2023-05-10 11:18:29 +0800 | [diff] [blame] | 1647 | nr_failed++; |
Huang Ying | 6f7d760 | 2023-02-13 20:34:44 +0800 | [diff] [blame] | 1648 | stats->nr_thp_failed++; |
Huang Ying | a21d213 | 2023-03-03 11:01:54 +0800 | [diff] [blame] | 1649 | if (!try_split_folio(folio, split_folios)) { |
Huang Ying | 6f7d760 | 2023-02-13 20:34:44 +0800 | [diff] [blame] | 1650 | stats->nr_thp_split++; |
| 1651 | continue; |
| 1652 | } |
| 1653 | stats->nr_failed_pages += nr_pages; |
| 1654 | list_move_tail(&folio->lru, ret_folios); |
| 1655 | continue; |
| 1656 | } |
| 1657 | |
Matthew Wilcox (Oracle) | 4e096ae | 2023-05-13 01:11:01 +0100 | [diff] [blame] | 1658 | rc = migrate_folio_unmap(get_new_folio, put_new_folio, |
| 1659 | private, folio, &dst, mode, reason, |
| 1660 | ret_folios); |
Huang Ying | 42012e0 | 2023-02-13 20:34:38 +0800 | [diff] [blame] | 1661 | /* |
| 1662 | * The rules are: |
| 1663 | * Success: folio will be freed |
Huang Ying | 5dfab10 | 2023-02-13 20:34:40 +0800 | [diff] [blame] | 1664 | * Unmap: folio will be put on unmap_folios list, |
| 1665 | * dst folio put on dst_folios list |
Huang Ying | 42012e0 | 2023-02-13 20:34:38 +0800 | [diff] [blame] | 1666 | * -EAGAIN: stay on the from list |
| 1667 | * -ENOMEM: stay on the from list |
Huang Ying | 42012e0 | 2023-02-13 20:34:38 +0800 | [diff] [blame] | 1668 | * Other errno: put on ret_folios list |
| 1669 | */ |
| 1670 | switch(rc) { |
Huang Ying | 42012e0 | 2023-02-13 20:34:38 +0800 | [diff] [blame] | 1671 | case -ENOMEM: |
| 1672 | /* |
| 1673 | * When memory is low, don't bother to try to migrate |
Huang Ying | 5dfab10 | 2023-02-13 20:34:40 +0800 | [diff] [blame] | 1674 | * other folios, move unmapped folios, then exit. |
Huang Ying | 42012e0 | 2023-02-13 20:34:38 +0800 | [diff] [blame] | 1675 | */ |
Huang Ying | 124abce | 2023-05-10 11:18:29 +0800 | [diff] [blame] | 1676 | nr_failed++; |
| 1677 | stats->nr_thp_failed += is_thp; |
| 1678 | /* Large folio NUMA faulting doesn't split to retry. */ |
| 1679 | if (folio_test_large(folio) && !nosplit) { |
| 1680 | int ret = try_split_folio(folio, split_folios); |
Huang Ying | 42012e0 | 2023-02-13 20:34:38 +0800 | [diff] [blame] | 1681 | |
Huang Ying | 124abce | 2023-05-10 11:18:29 +0800 | [diff] [blame] | 1682 | if (!ret) { |
| 1683 | stats->nr_thp_split += is_thp; |
| 1684 | break; |
| 1685 | } else if (reason == MR_LONGTERM_PIN && |
| 1686 | ret == -EAGAIN) { |
| 1687 | /* |
| 1688 | * Try again to split large folio to |
| 1689 | * mitigate the failure of longterm pinning. |
| 1690 | */ |
| 1691 | retry++; |
| 1692 | thp_retry += is_thp; |
| 1693 | nr_retry_pages += nr_pages; |
| 1694 | /* Undo duplicated failure counting. */ |
| 1695 | nr_failed--; |
| 1696 | stats->nr_thp_failed -= is_thp; |
| 1697 | break; |
Huang Ying | 42012e0 | 2023-02-13 20:34:38 +0800 | [diff] [blame] | 1698 | } |
Huang Ying | 42012e0 | 2023-02-13 20:34:38 +0800 | [diff] [blame] | 1699 | } |
| 1700 | |
| 1701 | stats->nr_failed_pages += nr_pages + nr_retry_pages; |
Huang Ying | 42012e0 | 2023-02-13 20:34:38 +0800 | [diff] [blame] | 1702 | /* nr_failed isn't updated for not used */ |
Huang Ying | 42012e0 | 2023-02-13 20:34:38 +0800 | [diff] [blame] | 1703 | stats->nr_thp_failed += thp_retry; |
Huang Ying | 5dfab10 | 2023-02-13 20:34:40 +0800 | [diff] [blame] | 1704 | rc_saved = rc; |
| 1705 | if (list_empty(&unmap_folios)) |
| 1706 | goto out; |
| 1707 | else |
| 1708 | goto move; |
Huang Ying | 42012e0 | 2023-02-13 20:34:38 +0800 | [diff] [blame] | 1709 | case -EAGAIN: |
Huang Ying | 124abce | 2023-05-10 11:18:29 +0800 | [diff] [blame] | 1710 | retry++; |
| 1711 | thp_retry += is_thp; |
Huang Ying | 42012e0 | 2023-02-13 20:34:38 +0800 | [diff] [blame] | 1712 | nr_retry_pages += nr_pages; |
| 1713 | break; |
| 1714 | case MIGRATEPAGE_SUCCESS: |
| 1715 | stats->nr_succeeded += nr_pages; |
| 1716 | stats->nr_thp_succeeded += is_thp; |
| 1717 | break; |
Huang Ying | 5dfab10 | 2023-02-13 20:34:40 +0800 | [diff] [blame] | 1718 | case MIGRATEPAGE_UNMAP: |
Huang Ying | 5dfab10 | 2023-02-13 20:34:40 +0800 | [diff] [blame] | 1719 | list_move_tail(&folio->lru, &unmap_folios); |
| 1720 | list_add_tail(&dst->lru, &dst_folios); |
| 1721 | break; |
Huang Ying | 42012e0 | 2023-02-13 20:34:38 +0800 | [diff] [blame] | 1722 | default: |
| 1723 | /* |
| 1724 | * Permanent failure (-EBUSY, etc.): |
| 1725 | * unlike -EAGAIN case, the failed folio is |
| 1726 | * removed from migration folio list and not |
| 1727 | * retried in the next outer loop. |
| 1728 | */ |
Huang Ying | 124abce | 2023-05-10 11:18:29 +0800 | [diff] [blame] | 1729 | nr_failed++; |
| 1730 | stats->nr_thp_failed += is_thp; |
Huang Ying | 42012e0 | 2023-02-13 20:34:38 +0800 | [diff] [blame] | 1731 | stats->nr_failed_pages += nr_pages; |
| 1732 | break; |
| 1733 | } |
| 1734 | } |
| 1735 | } |
| 1736 | nr_failed += retry; |
Huang Ying | 42012e0 | 2023-02-13 20:34:38 +0800 | [diff] [blame] | 1737 | stats->nr_thp_failed += thp_retry; |
| 1738 | stats->nr_failed_pages += nr_retry_pages; |
Huang Ying | 5dfab10 | 2023-02-13 20:34:40 +0800 | [diff] [blame] | 1739 | move: |
Huang Ying | 7e12beb | 2023-02-13 20:34:43 +0800 | [diff] [blame] | 1740 | /* Flush TLBs for all unmapped folios */ |
| 1741 | try_to_unmap_flush(); |
| 1742 | |
Huang Ying | 5dfab10 | 2023-02-13 20:34:40 +0800 | [diff] [blame] | 1743 | retry = 1; |
Huang Ying | 124abce | 2023-05-10 11:18:29 +0800 | [diff] [blame] | 1744 | for (pass = 0; pass < nr_pass && retry; pass++) { |
Huang Ying | 5dfab10 | 2023-02-13 20:34:40 +0800 | [diff] [blame] | 1745 | retry = 0; |
Huang Ying | 5dfab10 | 2023-02-13 20:34:40 +0800 | [diff] [blame] | 1746 | thp_retry = 0; |
| 1747 | nr_retry_pages = 0; |
| 1748 | |
| 1749 | dst = list_first_entry(&dst_folios, struct folio, lru); |
| 1750 | dst2 = list_next_entry(dst, lru); |
| 1751 | list_for_each_entry_safe(folio, folio2, &unmap_folios, lru) { |
Huang Ying | 124abce | 2023-05-10 11:18:29 +0800 | [diff] [blame] | 1752 | is_thp = folio_test_large(folio) && folio_test_pmd_mappable(folio); |
Huang Ying | 5dfab10 | 2023-02-13 20:34:40 +0800 | [diff] [blame] | 1753 | nr_pages = folio_nr_pages(folio); |
| 1754 | |
| 1755 | cond_resched(); |
| 1756 | |
Matthew Wilcox (Oracle) | 4e096ae | 2023-05-13 01:11:01 +0100 | [diff] [blame] | 1757 | rc = migrate_folio_move(put_new_folio, private, |
Huang Ying | 5dfab10 | 2023-02-13 20:34:40 +0800 | [diff] [blame] | 1758 | folio, dst, mode, |
| 1759 | reason, ret_folios); |
| 1760 | /* |
| 1761 | * The rules are: |
| 1762 | * Success: folio will be freed |
| 1763 | * -EAGAIN: stay on the unmap_folios list |
| 1764 | * Other errno: put on ret_folios list |
| 1765 | */ |
| 1766 | switch(rc) { |
| 1767 | case -EAGAIN: |
Huang Ying | 124abce | 2023-05-10 11:18:29 +0800 | [diff] [blame] | 1768 | retry++; |
| 1769 | thp_retry += is_thp; |
Huang Ying | 5dfab10 | 2023-02-13 20:34:40 +0800 | [diff] [blame] | 1770 | nr_retry_pages += nr_pages; |
| 1771 | break; |
| 1772 | case MIGRATEPAGE_SUCCESS: |
| 1773 | stats->nr_succeeded += nr_pages; |
| 1774 | stats->nr_thp_succeeded += is_thp; |
| 1775 | break; |
| 1776 | default: |
Huang Ying | 124abce | 2023-05-10 11:18:29 +0800 | [diff] [blame] | 1777 | nr_failed++; |
| 1778 | stats->nr_thp_failed += is_thp; |
Huang Ying | 5dfab10 | 2023-02-13 20:34:40 +0800 | [diff] [blame] | 1779 | stats->nr_failed_pages += nr_pages; |
| 1780 | break; |
| 1781 | } |
| 1782 | dst = dst2; |
| 1783 | dst2 = list_next_entry(dst, lru); |
| 1784 | } |
| 1785 | } |
| 1786 | nr_failed += retry; |
Huang Ying | 5dfab10 | 2023-02-13 20:34:40 +0800 | [diff] [blame] | 1787 | stats->nr_thp_failed += thp_retry; |
| 1788 | stats->nr_failed_pages += nr_retry_pages; |
| 1789 | |
Huang Ying | 124abce | 2023-05-10 11:18:29 +0800 | [diff] [blame] | 1790 | rc = rc_saved ? : nr_failed; |
Huang Ying | 5dfab10 | 2023-02-13 20:34:40 +0800 | [diff] [blame] | 1791 | out: |
| 1792 | /* Cleanup remaining folios */ |
| 1793 | dst = list_first_entry(&dst_folios, struct folio, lru); |
| 1794 | dst2 = list_next_entry(dst, lru); |
| 1795 | list_for_each_entry_safe(folio, folio2, &unmap_folios, lru) { |
| 1796 | int page_was_mapped = 0; |
| 1797 | struct anon_vma *anon_vma = NULL; |
| 1798 | |
| 1799 | __migrate_folio_extract(dst, &page_was_mapped, &anon_vma); |
| 1800 | migrate_folio_undo_src(folio, page_was_mapped, anon_vma, |
Huang Ying | ebe75e4 | 2023-02-13 20:34:42 +0800 | [diff] [blame] | 1801 | true, ret_folios); |
Huang Ying | 5dfab10 | 2023-02-13 20:34:40 +0800 | [diff] [blame] | 1802 | list_del(&dst->lru); |
Matthew Wilcox (Oracle) | 4e096ae | 2023-05-13 01:11:01 +0100 | [diff] [blame] | 1803 | migrate_folio_undo_dst(dst, true, put_new_folio, private); |
Huang Ying | 5dfab10 | 2023-02-13 20:34:40 +0800 | [diff] [blame] | 1804 | dst = dst2; |
| 1805 | dst2 = list_next_entry(dst, lru); |
| 1806 | } |
| 1807 | |
Huang Ying | 42012e0 | 2023-02-13 20:34:38 +0800 | [diff] [blame] | 1808 | return rc; |
| 1809 | } |
| 1810 | |
Matthew Wilcox (Oracle) | 4e096ae | 2023-05-13 01:11:01 +0100 | [diff] [blame] | 1811 | static int migrate_pages_sync(struct list_head *from, new_folio_t get_new_folio, |
| 1812 | free_folio_t put_new_folio, unsigned long private, |
| 1813 | enum migrate_mode mode, int reason, |
| 1814 | struct list_head *ret_folios, struct list_head *split_folios, |
| 1815 | struct migrate_pages_stats *stats) |
Huang Ying | 2ef7dbb | 2023-03-03 11:01:55 +0800 | [diff] [blame] | 1816 | { |
| 1817 | int rc, nr_failed = 0; |
| 1818 | LIST_HEAD(folios); |
| 1819 | struct migrate_pages_stats astats; |
| 1820 | |
| 1821 | memset(&astats, 0, sizeof(astats)); |
| 1822 | /* Try to migrate in batch with MIGRATE_ASYNC mode firstly */ |
Matthew Wilcox (Oracle) | 4e096ae | 2023-05-13 01:11:01 +0100 | [diff] [blame] | 1823 | rc = migrate_pages_batch(from, get_new_folio, put_new_folio, private, MIGRATE_ASYNC, |
Huang Ying | 2ef7dbb | 2023-03-03 11:01:55 +0800 | [diff] [blame] | 1824 | reason, &folios, split_folios, &astats, |
| 1825 | NR_MAX_MIGRATE_ASYNC_RETRY); |
| 1826 | stats->nr_succeeded += astats.nr_succeeded; |
| 1827 | stats->nr_thp_succeeded += astats.nr_thp_succeeded; |
| 1828 | stats->nr_thp_split += astats.nr_thp_split; |
| 1829 | if (rc < 0) { |
| 1830 | stats->nr_failed_pages += astats.nr_failed_pages; |
| 1831 | stats->nr_thp_failed += astats.nr_thp_failed; |
| 1832 | list_splice_tail(&folios, ret_folios); |
| 1833 | return rc; |
| 1834 | } |
| 1835 | stats->nr_thp_failed += astats.nr_thp_split; |
| 1836 | nr_failed += astats.nr_thp_split; |
| 1837 | /* |
| 1838 | * Fall back to migrate all failed folios one by one synchronously. All |
| 1839 | * failed folios except split THPs will be retried, so their failure |
| 1840 | * isn't counted |
| 1841 | */ |
| 1842 | list_splice_tail_init(&folios, from); |
| 1843 | while (!list_empty(from)) { |
| 1844 | list_move(from->next, &folios); |
Matthew Wilcox (Oracle) | 4e096ae | 2023-05-13 01:11:01 +0100 | [diff] [blame] | 1845 | rc = migrate_pages_batch(&folios, get_new_folio, put_new_folio, |
Huang Ying | 2ef7dbb | 2023-03-03 11:01:55 +0800 | [diff] [blame] | 1846 | private, mode, reason, ret_folios, |
| 1847 | split_folios, stats, NR_MAX_MIGRATE_SYNC_RETRY); |
| 1848 | list_splice_tail_init(&folios, ret_folios); |
| 1849 | if (rc < 0) |
| 1850 | return rc; |
| 1851 | nr_failed += rc; |
| 1852 | } |
| 1853 | |
| 1854 | return nr_failed; |
| 1855 | } |
| 1856 | |
Christoph Lameter | b20a350 | 2006-03-22 00:09:12 -0800 | [diff] [blame] | 1857 | /* |
Huang Ying | eaec4e6 | 2022-11-09 09:23:48 +0800 | [diff] [blame] | 1858 | * migrate_pages - migrate the folios specified in a list, to the free folios |
Srivatsa S. Bhat | c73e5c9 | 2013-04-29 15:08:16 -0700 | [diff] [blame] | 1859 | * supplied as the target for the page migration |
Christoph Lameter | b20a350 | 2006-03-22 00:09:12 -0800 | [diff] [blame] | 1860 | * |
Huang Ying | eaec4e6 | 2022-11-09 09:23:48 +0800 | [diff] [blame] | 1861 | * @from: The list of folios to be migrated. |
Matthew Wilcox (Oracle) | 4e096ae | 2023-05-13 01:11:01 +0100 | [diff] [blame] | 1862 | * @get_new_folio: The function used to allocate free folios to be used |
Huang Ying | eaec4e6 | 2022-11-09 09:23:48 +0800 | [diff] [blame] | 1863 | * as the target of the folio migration. |
Matthew Wilcox (Oracle) | 4e096ae | 2023-05-13 01:11:01 +0100 | [diff] [blame] | 1864 | * @put_new_folio: The function used to free target folios if migration |
David Rientjes | 68711a7 | 2014-06-04 16:08:25 -0700 | [diff] [blame] | 1865 | * fails, or NULL if no special handling is necessary. |
Matthew Wilcox (Oracle) | 4e096ae | 2023-05-13 01:11:01 +0100 | [diff] [blame] | 1866 | * @private: Private data to be passed on to get_new_folio() |
Srivatsa S. Bhat | c73e5c9 | 2013-04-29 15:08:16 -0700 | [diff] [blame] | 1867 | * @mode: The migration mode that specifies the constraints for |
Huang Ying | eaec4e6 | 2022-11-09 09:23:48 +0800 | [diff] [blame] | 1868 | * folio migration, if any. |
| 1869 | * @reason: The reason for folio migration. |
| 1870 | * @ret_succeeded: Set to the number of folios migrated successfully if |
Yang Shi | 5ac9588 | 2021-09-02 14:59:13 -0700 | [diff] [blame] | 1871 | * the caller passes a non-NULL pointer. |
Christoph Lameter | b20a350 | 2006-03-22 00:09:12 -0800 | [diff] [blame] | 1872 | * |
Huang Ying | e5bfff8b | 2023-02-13 20:34:37 +0800 | [diff] [blame] | 1873 | * The function returns after NR_MAX_MIGRATE_PAGES_RETRY attempts or if no folios |
| 1874 | * are movable any more because the list has become empty or no retryable folios |
| 1875 | * exist any more. It is caller's responsibility to call putback_movable_pages() |
| 1876 | * only if ret != 0. |
Christoph Lameter | b20a350 | 2006-03-22 00:09:12 -0800 | [diff] [blame] | 1877 | * |
Huang Ying | eaec4e6 | 2022-11-09 09:23:48 +0800 | [diff] [blame] | 1878 | * Returns the number of {normal folio, large folio, hugetlb} that were not |
| 1879 | * migrated, or an error code. The number of large folio splits will be |
| 1880 | * considered as the number of non-migrated large folio, no matter how many |
| 1881 | * split folios of the large folio are migrated successfully. |
Christoph Lameter | b20a350 | 2006-03-22 00:09:12 -0800 | [diff] [blame] | 1882 | */ |
Matthew Wilcox (Oracle) | 4e096ae | 2023-05-13 01:11:01 +0100 | [diff] [blame] | 1883 | int migrate_pages(struct list_head *from, new_folio_t get_new_folio, |
| 1884 | free_folio_t put_new_folio, unsigned long private, |
Yang Shi | 5ac9588 | 2021-09-02 14:59:13 -0700 | [diff] [blame] | 1885 | enum migrate_mode mode, int reason, unsigned int *ret_succeeded) |
Christoph Lameter | b20a350 | 2006-03-22 00:09:12 -0800 | [diff] [blame] | 1886 | { |
Huang Ying | 42012e0 | 2023-02-13 20:34:38 +0800 | [diff] [blame] | 1887 | int rc, rc_gather; |
Huang Ying | 2ef7dbb | 2023-03-03 11:01:55 +0800 | [diff] [blame] | 1888 | int nr_pages; |
Huang Ying | eaec4e6 | 2022-11-09 09:23:48 +0800 | [diff] [blame] | 1889 | struct folio *folio, *folio2; |
Huang Ying | 42012e0 | 2023-02-13 20:34:38 +0800 | [diff] [blame] | 1890 | LIST_HEAD(folios); |
Huang Ying | eaec4e6 | 2022-11-09 09:23:48 +0800 | [diff] [blame] | 1891 | LIST_HEAD(ret_folios); |
Huang Ying | a21d213 | 2023-03-03 11:01:54 +0800 | [diff] [blame] | 1892 | LIST_HEAD(split_folios); |
Huang Ying | 5b85593 | 2023-02-13 20:34:36 +0800 | [diff] [blame] | 1893 | struct migrate_pages_stats stats; |
Christoph Lameter | b20a350 | 2006-03-22 00:09:12 -0800 | [diff] [blame] | 1894 | |
Liam Mark | 7bc1aec | 2021-05-04 18:37:25 -0700 | [diff] [blame] | 1895 | trace_mm_migrate_pages_start(mode, reason); |
| 1896 | |
Huang Ying | 5b85593 | 2023-02-13 20:34:36 +0800 | [diff] [blame] | 1897 | memset(&stats, 0, sizeof(stats)); |
Christoph Lameter | b20a350 | 2006-03-22 00:09:12 -0800 | [diff] [blame] | 1898 | |
Matthew Wilcox (Oracle) | 4e096ae | 2023-05-13 01:11:01 +0100 | [diff] [blame] | 1899 | rc_gather = migrate_hugetlbs(from, get_new_folio, put_new_folio, private, |
Huang Ying | 42012e0 | 2023-02-13 20:34:38 +0800 | [diff] [blame] | 1900 | mode, reason, &stats, &ret_folios); |
| 1901 | if (rc_gather < 0) |
Huang Ying | e5bfff8b | 2023-02-13 20:34:37 +0800 | [diff] [blame] | 1902 | goto out; |
Huang Ying | fb3592c | 2023-03-03 11:01:53 +0800 | [diff] [blame] | 1903 | |
Huang Ying | 42012e0 | 2023-02-13 20:34:38 +0800 | [diff] [blame] | 1904 | again: |
| 1905 | nr_pages = 0; |
| 1906 | list_for_each_entry_safe(folio, folio2, from, lru) { |
| 1907 | /* Retried hugetlb folios will be kept in list */ |
| 1908 | if (folio_test_hugetlb(folio)) { |
| 1909 | list_move_tail(&folio->lru, &ret_folios); |
| 1910 | continue; |
Christoph Lameter | b20a350 | 2006-03-22 00:09:12 -0800 | [diff] [blame] | 1911 | } |
Baolin Wang | b5bade9 | 2022-01-14 14:08:34 -0800 | [diff] [blame] | 1912 | |
Huang Ying | 42012e0 | 2023-02-13 20:34:38 +0800 | [diff] [blame] | 1913 | nr_pages += folio_nr_pages(folio); |
Huang Ying | 2ef7dbb | 2023-03-03 11:01:55 +0800 | [diff] [blame] | 1914 | if (nr_pages >= NR_MAX_BATCHED_MIGRATION) |
Huang Ying | 42012e0 | 2023-02-13 20:34:38 +0800 | [diff] [blame] | 1915 | break; |
| 1916 | } |
Huang Ying | 2ef7dbb | 2023-03-03 11:01:55 +0800 | [diff] [blame] | 1917 | if (nr_pages >= NR_MAX_BATCHED_MIGRATION) |
Huang Ying | fb3592c | 2023-03-03 11:01:53 +0800 | [diff] [blame] | 1918 | list_cut_before(&folios, from, &folio2->lru); |
Huang Ying | 42012e0 | 2023-02-13 20:34:38 +0800 | [diff] [blame] | 1919 | else |
| 1920 | list_splice_init(from, &folios); |
Huang Ying | 2ef7dbb | 2023-03-03 11:01:55 +0800 | [diff] [blame] | 1921 | if (mode == MIGRATE_ASYNC) |
Matthew Wilcox (Oracle) | 4e096ae | 2023-05-13 01:11:01 +0100 | [diff] [blame] | 1922 | rc = migrate_pages_batch(&folios, get_new_folio, put_new_folio, |
| 1923 | private, mode, reason, &ret_folios, |
| 1924 | &split_folios, &stats, |
| 1925 | NR_MAX_MIGRATE_PAGES_RETRY); |
Huang Ying | 2ef7dbb | 2023-03-03 11:01:55 +0800 | [diff] [blame] | 1926 | else |
Matthew Wilcox (Oracle) | 4e096ae | 2023-05-13 01:11:01 +0100 | [diff] [blame] | 1927 | rc = migrate_pages_sync(&folios, get_new_folio, put_new_folio, |
| 1928 | private, mode, reason, &ret_folios, |
| 1929 | &split_folios, &stats); |
Huang Ying | 42012e0 | 2023-02-13 20:34:38 +0800 | [diff] [blame] | 1930 | list_splice_tail_init(&folios, &ret_folios); |
| 1931 | if (rc < 0) { |
| 1932 | rc_gather = rc; |
Huang Ying | a21d213 | 2023-03-03 11:01:54 +0800 | [diff] [blame] | 1933 | list_splice_tail(&split_folios, &ret_folios); |
Huang Ying | 42012e0 | 2023-02-13 20:34:38 +0800 | [diff] [blame] | 1934 | goto out; |
| 1935 | } |
Huang Ying | a21d213 | 2023-03-03 11:01:54 +0800 | [diff] [blame] | 1936 | if (!list_empty(&split_folios)) { |
| 1937 | /* |
| 1938 | * Failure isn't counted since all split folios of a large folio |
| 1939 | * is counted as 1 failure already. And, we only try to migrate |
| 1940 | * with minimal effort, force MIGRATE_ASYNC mode and retry once. |
| 1941 | */ |
Matthew Wilcox (Oracle) | 4e096ae | 2023-05-13 01:11:01 +0100 | [diff] [blame] | 1942 | migrate_pages_batch(&split_folios, get_new_folio, |
| 1943 | put_new_folio, private, MIGRATE_ASYNC, reason, |
| 1944 | &ret_folios, NULL, &stats, 1); |
Huang Ying | a21d213 | 2023-03-03 11:01:54 +0800 | [diff] [blame] | 1945 | list_splice_tail_init(&split_folios, &ret_folios); |
| 1946 | } |
Huang Ying | 42012e0 | 2023-02-13 20:34:38 +0800 | [diff] [blame] | 1947 | rc_gather += rc; |
| 1948 | if (!list_empty(from)) |
| 1949 | goto again; |
Christoph Lameter | 95a402c | 2006-06-23 02:03:53 -0700 | [diff] [blame] | 1950 | out: |
Yang Shi | dd4ae78 | 2020-12-14 19:13:06 -0800 | [diff] [blame] | 1951 | /* |
Huang Ying | eaec4e6 | 2022-11-09 09:23:48 +0800 | [diff] [blame] | 1952 | * Put the permanent failure folio back to migration list, they |
Yang Shi | dd4ae78 | 2020-12-14 19:13:06 -0800 | [diff] [blame] | 1953 | * will be put back to the right list by the caller. |
| 1954 | */ |
Huang Ying | eaec4e6 | 2022-11-09 09:23:48 +0800 | [diff] [blame] | 1955 | list_splice(&ret_folios, from); |
Yang Shi | dd4ae78 | 2020-12-14 19:13:06 -0800 | [diff] [blame] | 1956 | |
Baolin Wang | 03e5f82 | 2022-10-24 16:34:21 +0800 | [diff] [blame] | 1957 | /* |
Huang Ying | eaec4e6 | 2022-11-09 09:23:48 +0800 | [diff] [blame] | 1958 | * Return 0 in case all split folios of fail-to-migrate large folios |
| 1959 | * are migrated successfully. |
Baolin Wang | 03e5f82 | 2022-10-24 16:34:21 +0800 | [diff] [blame] | 1960 | */ |
| 1961 | if (list_empty(from)) |
Huang Ying | 42012e0 | 2023-02-13 20:34:38 +0800 | [diff] [blame] | 1962 | rc_gather = 0; |
Baolin Wang | 03e5f82 | 2022-10-24 16:34:21 +0800 | [diff] [blame] | 1963 | |
Huang Ying | 5b85593 | 2023-02-13 20:34:36 +0800 | [diff] [blame] | 1964 | count_vm_events(PGMIGRATE_SUCCESS, stats.nr_succeeded); |
| 1965 | count_vm_events(PGMIGRATE_FAIL, stats.nr_failed_pages); |
| 1966 | count_vm_events(THP_MIGRATION_SUCCESS, stats.nr_thp_succeeded); |
| 1967 | count_vm_events(THP_MIGRATION_FAIL, stats.nr_thp_failed); |
| 1968 | count_vm_events(THP_MIGRATION_SPLIT, stats.nr_thp_split); |
| 1969 | trace_mm_migrate_pages(stats.nr_succeeded, stats.nr_failed_pages, |
| 1970 | stats.nr_thp_succeeded, stats.nr_thp_failed, |
| 1971 | stats.nr_thp_split, mode, reason); |
Mel Gorman | 7b2a2d4 | 2012-10-19 14:07:31 +0100 | [diff] [blame] | 1972 | |
Yang Shi | 5ac9588 | 2021-09-02 14:59:13 -0700 | [diff] [blame] | 1973 | if (ret_succeeded) |
Huang Ying | 5b85593 | 2023-02-13 20:34:36 +0800 | [diff] [blame] | 1974 | *ret_succeeded = stats.nr_succeeded; |
Yang Shi | 5ac9588 | 2021-09-02 14:59:13 -0700 | [diff] [blame] | 1975 | |
Huang Ying | 42012e0 | 2023-02-13 20:34:38 +0800 | [diff] [blame] | 1976 | return rc_gather; |
Christoph Lameter | b20a350 | 2006-03-22 00:09:12 -0800 | [diff] [blame] | 1977 | } |
| 1978 | |
Matthew Wilcox (Oracle) | 4e096ae | 2023-05-13 01:11:01 +0100 | [diff] [blame] | 1979 | struct folio *alloc_migration_target(struct folio *src, unsigned long private) |
Joonsoo Kim | b4b3822 | 2020-08-11 18:37:14 -0700 | [diff] [blame] | 1980 | { |
Joonsoo Kim | 19fc7be | 2020-08-11 18:37:25 -0700 | [diff] [blame] | 1981 | struct migration_target_control *mtc; |
| 1982 | gfp_t gfp_mask; |
Joonsoo Kim | b4b3822 | 2020-08-11 18:37:14 -0700 | [diff] [blame] | 1983 | unsigned int order = 0; |
Joonsoo Kim | 19fc7be | 2020-08-11 18:37:25 -0700 | [diff] [blame] | 1984 | int nid; |
| 1985 | int zidx; |
| 1986 | |
| 1987 | mtc = (struct migration_target_control *)private; |
| 1988 | gfp_mask = mtc->gfp_mask; |
| 1989 | nid = mtc->nid; |
| 1990 | if (nid == NUMA_NO_NODE) |
Matthew Wilcox (Oracle) | 4e096ae | 2023-05-13 01:11:01 +0100 | [diff] [blame] | 1991 | nid = folio_nid(src); |
Joonsoo Kim | b4b3822 | 2020-08-11 18:37:14 -0700 | [diff] [blame] | 1992 | |
Matthew Wilcox (Oracle) | 4e096ae | 2023-05-13 01:11:01 +0100 | [diff] [blame] | 1993 | if (folio_test_hugetlb(src)) { |
| 1994 | struct hstate *h = folio_hstate(src); |
Joonsoo Kim | d92bbc2 | 2020-08-11 18:37:17 -0700 | [diff] [blame] | 1995 | |
Joonsoo Kim | 19fc7be | 2020-08-11 18:37:25 -0700 | [diff] [blame] | 1996 | gfp_mask = htlb_modify_alloc_mask(h, gfp_mask); |
Matthew Wilcox (Oracle) | 4e096ae | 2023-05-13 01:11:01 +0100 | [diff] [blame] | 1997 | return alloc_hugetlb_folio_nodemask(h, nid, |
Sidhartha Kumar | e37d3e8 | 2023-01-13 16:30:55 -0600 | [diff] [blame] | 1998 | mtc->nmask, gfp_mask); |
Joonsoo Kim | d92bbc2 | 2020-08-11 18:37:17 -0700 | [diff] [blame] | 1999 | } |
Joonsoo Kim | b4b3822 | 2020-08-11 18:37:14 -0700 | [diff] [blame] | 2000 | |
Matthew Wilcox (Oracle) | 4e096ae | 2023-05-13 01:11:01 +0100 | [diff] [blame] | 2001 | if (folio_test_large(src)) { |
Joonsoo Kim | 9933a0c | 2020-08-11 18:37:20 -0700 | [diff] [blame] | 2002 | /* |
| 2003 | * clear __GFP_RECLAIM to make the migration callback |
| 2004 | * consistent with regular THP allocations. |
| 2005 | */ |
| 2006 | gfp_mask &= ~__GFP_RECLAIM; |
Joonsoo Kim | b4b3822 | 2020-08-11 18:37:14 -0700 | [diff] [blame] | 2007 | gfp_mask |= GFP_TRANSHUGE; |
Matthew Wilcox (Oracle) | 4e096ae | 2023-05-13 01:11:01 +0100 | [diff] [blame] | 2008 | order = folio_order(src); |
Joonsoo Kim | b4b3822 | 2020-08-11 18:37:14 -0700 | [diff] [blame] | 2009 | } |
Matthew Wilcox (Oracle) | 4e096ae | 2023-05-13 01:11:01 +0100 | [diff] [blame] | 2010 | zidx = zone_idx(folio_zone(src)); |
Joonsoo Kim | 19fc7be | 2020-08-11 18:37:25 -0700 | [diff] [blame] | 2011 | if (is_highmem_idx(zidx) || zidx == ZONE_MOVABLE) |
Joonsoo Kim | b4b3822 | 2020-08-11 18:37:14 -0700 | [diff] [blame] | 2012 | gfp_mask |= __GFP_HIGHMEM; |
| 2013 | |
Matthew Wilcox (Oracle) | 4e096ae | 2023-05-13 01:11:01 +0100 | [diff] [blame] | 2014 | return __folio_alloc(gfp_mask, order, nid, mtc->nmask); |
Joonsoo Kim | b4b3822 | 2020-08-11 18:37:14 -0700 | [diff] [blame] | 2015 | } |
| 2016 | |
Christoph Lameter | 742755a | 2006-06-23 02:03:55 -0700 | [diff] [blame] | 2017 | #ifdef CONFIG_NUMA |
Christoph Lameter | 742755a | 2006-06-23 02:03:55 -0700 | [diff] [blame] | 2018 | |
Michal Hocko | a49bd4d | 2018-04-10 16:29:59 -0700 | [diff] [blame] | 2019 | static int store_status(int __user *status, int start, int value, int nr) |
Christoph Lameter | 742755a | 2006-06-23 02:03:55 -0700 | [diff] [blame] | 2020 | { |
Michal Hocko | a49bd4d | 2018-04-10 16:29:59 -0700 | [diff] [blame] | 2021 | while (nr-- > 0) { |
| 2022 | if (put_user(value, status + start)) |
| 2023 | return -EFAULT; |
| 2024 | start++; |
| 2025 | } |
Christoph Lameter | 742755a | 2006-06-23 02:03:55 -0700 | [diff] [blame] | 2026 | |
Michal Hocko | a49bd4d | 2018-04-10 16:29:59 -0700 | [diff] [blame] | 2027 | return 0; |
| 2028 | } |
Christoph Lameter | 742755a | 2006-06-23 02:03:55 -0700 | [diff] [blame] | 2029 | |
Michal Hocko | a49bd4d | 2018-04-10 16:29:59 -0700 | [diff] [blame] | 2030 | static int do_move_pages_to_node(struct mm_struct *mm, |
| 2031 | struct list_head *pagelist, int node) |
| 2032 | { |
| 2033 | int err; |
Joonsoo Kim | a097631 | 2020-08-11 18:37:28 -0700 | [diff] [blame] | 2034 | struct migration_target_control mtc = { |
| 2035 | .nid = node, |
| 2036 | .gfp_mask = GFP_HIGHUSER_MOVABLE | __GFP_THISNODE, |
| 2037 | }; |
Christoph Lameter | 742755a | 2006-06-23 02:03:55 -0700 | [diff] [blame] | 2038 | |
Joonsoo Kim | a097631 | 2020-08-11 18:37:28 -0700 | [diff] [blame] | 2039 | err = migrate_pages(pagelist, alloc_migration_target, NULL, |
Yang Shi | 5ac9588 | 2021-09-02 14:59:13 -0700 | [diff] [blame] | 2040 | (unsigned long)&mtc, MIGRATE_SYNC, MR_SYSCALL, NULL); |
Michal Hocko | a49bd4d | 2018-04-10 16:29:59 -0700 | [diff] [blame] | 2041 | if (err) |
| 2042 | putback_movable_pages(pagelist); |
| 2043 | return err; |
Christoph Lameter | 742755a | 2006-06-23 02:03:55 -0700 | [diff] [blame] | 2044 | } |
| 2045 | |
| 2046 | /* |
Michal Hocko | a49bd4d | 2018-04-10 16:29:59 -0700 | [diff] [blame] | 2047 | * Resolves the given address to a struct page, isolates it from the LRU and |
| 2048 | * puts it to the given pagelist. |
Yang Shi | e0153fc | 2020-01-04 12:59:46 -0800 | [diff] [blame] | 2049 | * Returns: |
| 2050 | * errno - if the page cannot be found/isolated |
| 2051 | * 0 - when it doesn't have to be migrated because it is already on the |
| 2052 | * target node |
| 2053 | * 1 - when it has been queued |
Christoph Lameter | 742755a | 2006-06-23 02:03:55 -0700 | [diff] [blame] | 2054 | */ |
Kirill A. Shutemov | 428e106 | 2023-03-12 14:26:00 +0300 | [diff] [blame] | 2055 | static int add_page_for_migration(struct mm_struct *mm, const void __user *p, |
Michal Hocko | a49bd4d | 2018-04-10 16:29:59 -0700 | [diff] [blame] | 2056 | int node, struct list_head *pagelist, bool migrate_all) |
Christoph Lameter | 742755a | 2006-06-23 02:03:55 -0700 | [diff] [blame] | 2057 | { |
Michal Hocko | a49bd4d | 2018-04-10 16:29:59 -0700 | [diff] [blame] | 2058 | struct vm_area_struct *vma; |
Kirill A. Shutemov | 428e106 | 2023-03-12 14:26:00 +0300 | [diff] [blame] | 2059 | unsigned long addr; |
Michal Hocko | a49bd4d | 2018-04-10 16:29:59 -0700 | [diff] [blame] | 2060 | struct page *page; |
Christoph Lameter | 742755a | 2006-06-23 02:03:55 -0700 | [diff] [blame] | 2061 | int err; |
Baolin Wang | 9747b9e | 2023-02-15 18:39:36 +0800 | [diff] [blame] | 2062 | bool isolated; |
Christoph Lameter | 742755a | 2006-06-23 02:03:55 -0700 | [diff] [blame] | 2063 | |
Michel Lespinasse | d8ed45c | 2020-06-08 21:33:25 -0700 | [diff] [blame] | 2064 | mmap_read_lock(mm); |
Kirill A. Shutemov | 428e106 | 2023-03-12 14:26:00 +0300 | [diff] [blame] | 2065 | addr = (unsigned long)untagged_addr_remote(mm, p); |
| 2066 | |
Michal Hocko | a49bd4d | 2018-04-10 16:29:59 -0700 | [diff] [blame] | 2067 | err = -EFAULT; |
Miaohe Lin | cb1c37b | 2022-04-28 23:16:07 -0700 | [diff] [blame] | 2068 | vma = vma_lookup(mm, addr); |
| 2069 | if (!vma || !vma_migratable(vma)) |
Michal Hocko | a49bd4d | 2018-04-10 16:29:59 -0700 | [diff] [blame] | 2070 | goto out; |
Christoph Lameter | 742755a | 2006-06-23 02:03:55 -0700 | [diff] [blame] | 2071 | |
Michal Hocko | a49bd4d | 2018-04-10 16:29:59 -0700 | [diff] [blame] | 2072 | /* FOLL_DUMP to ignore special (like zero) pages */ |
Miaohe Lin | 87d2762 | 2022-03-22 14:45:29 -0700 | [diff] [blame] | 2073 | page = follow_page(vma, addr, FOLL_GET | FOLL_DUMP); |
Christoph Lameter | 742755a | 2006-06-23 02:03:55 -0700 | [diff] [blame] | 2074 | |
Michal Hocko | a49bd4d | 2018-04-10 16:29:59 -0700 | [diff] [blame] | 2075 | err = PTR_ERR(page); |
| 2076 | if (IS_ERR(page)) |
| 2077 | goto out; |
Christoph Lameter | 742755a | 2006-06-23 02:03:55 -0700 | [diff] [blame] | 2078 | |
Michal Hocko | a49bd4d | 2018-04-10 16:29:59 -0700 | [diff] [blame] | 2079 | err = -ENOENT; |
Haiyue Wang | f7091ed | 2022-08-23 21:58:41 +0800 | [diff] [blame] | 2080 | if (!page) |
Michal Hocko | a49bd4d | 2018-04-10 16:29:59 -0700 | [diff] [blame] | 2081 | goto out; |
Christoph Lameter | 742755a | 2006-06-23 02:03:55 -0700 | [diff] [blame] | 2082 | |
Haiyue Wang | f7091ed | 2022-08-23 21:58:41 +0800 | [diff] [blame] | 2083 | if (is_zone_device_page(page)) |
| 2084 | goto out_putpage; |
| 2085 | |
Brice Goglin | e78bbfa | 2008-10-18 20:27:15 -0700 | [diff] [blame] | 2086 | err = 0; |
Michal Hocko | a49bd4d | 2018-04-10 16:29:59 -0700 | [diff] [blame] | 2087 | if (page_to_nid(page) == node) |
| 2088 | goto out_putpage; |
Christoph Lameter | 742755a | 2006-06-23 02:03:55 -0700 | [diff] [blame] | 2089 | |
Michal Hocko | a49bd4d | 2018-04-10 16:29:59 -0700 | [diff] [blame] | 2090 | err = -EACCES; |
| 2091 | if (page_mapcount(page) > 1 && !migrate_all) |
| 2092 | goto out_putpage; |
| 2093 | |
| 2094 | if (PageHuge(page)) { |
| 2095 | if (PageHead(page)) { |
Baolin Wang | 9747b9e | 2023-02-15 18:39:36 +0800 | [diff] [blame] | 2096 | isolated = isolate_hugetlb(page_folio(page), pagelist); |
| 2097 | err = isolated ? 1 : -EBUSY; |
Michal Hocko | a49bd4d | 2018-04-10 16:29:59 -0700 | [diff] [blame] | 2098 | } |
| 2099 | } else { |
| 2100 | struct page *head; |
| 2101 | |
| 2102 | head = compound_head(page); |
Baolin Wang | f7f9c00 | 2023-02-15 18:39:35 +0800 | [diff] [blame] | 2103 | isolated = isolate_lru_page(head); |
| 2104 | if (!isolated) { |
| 2105 | err = -EBUSY; |
Michal Hocko | a49bd4d | 2018-04-10 16:29:59 -0700 | [diff] [blame] | 2106 | goto out_putpage; |
Baolin Wang | f7f9c00 | 2023-02-15 18:39:35 +0800 | [diff] [blame] | 2107 | } |
Michal Hocko | a49bd4d | 2018-04-10 16:29:59 -0700 | [diff] [blame] | 2108 | |
Yang Shi | e0153fc | 2020-01-04 12:59:46 -0800 | [diff] [blame] | 2109 | err = 1; |
Michal Hocko | a49bd4d | 2018-04-10 16:29:59 -0700 | [diff] [blame] | 2110 | list_add_tail(&head->lru, pagelist); |
| 2111 | mod_node_page_state(page_pgdat(head), |
Huang Ying | 9de4f22 | 2020-04-06 20:04:41 -0700 | [diff] [blame] | 2112 | NR_ISOLATED_ANON + page_is_file_lru(head), |
Matthew Wilcox (Oracle) | 6c35784 | 2020-08-14 17:30:37 -0700 | [diff] [blame] | 2113 | thp_nr_pages(head)); |
Michal Hocko | a49bd4d | 2018-04-10 16:29:59 -0700 | [diff] [blame] | 2114 | } |
| 2115 | out_putpage: |
| 2116 | /* |
| 2117 | * Either remove the duplicate refcount from |
| 2118 | * isolate_lru_page() or drop the page ref if it was |
| 2119 | * not isolated. |
| 2120 | */ |
| 2121 | put_page(page); |
| 2122 | out: |
Michel Lespinasse | d8ed45c | 2020-06-08 21:33:25 -0700 | [diff] [blame] | 2123 | mmap_read_unlock(mm); |
Christoph Lameter | 742755a | 2006-06-23 02:03:55 -0700 | [diff] [blame] | 2124 | return err; |
| 2125 | } |
| 2126 | |
Wei Yang | 7ca8783 | 2020-04-06 20:04:12 -0700 | [diff] [blame] | 2127 | static int move_pages_and_store_status(struct mm_struct *mm, int node, |
| 2128 | struct list_head *pagelist, int __user *status, |
| 2129 | int start, int i, unsigned long nr_pages) |
| 2130 | { |
| 2131 | int err; |
| 2132 | |
Wei Yang | 5d7ae89 | 2020-04-06 20:04:15 -0700 | [diff] [blame] | 2133 | if (list_empty(pagelist)) |
| 2134 | return 0; |
| 2135 | |
Wei Yang | 7ca8783 | 2020-04-06 20:04:12 -0700 | [diff] [blame] | 2136 | err = do_move_pages_to_node(mm, pagelist, node); |
| 2137 | if (err) { |
| 2138 | /* |
| 2139 | * Positive err means the number of failed |
| 2140 | * pages to migrate. Since we are going to |
| 2141 | * abort and return the number of non-migrated |
Long Li | ab9dd4f | 2020-12-14 19:12:52 -0800 | [diff] [blame] | 2142 | * pages, so need to include the rest of the |
Wei Yang | 7ca8783 | 2020-04-06 20:04:12 -0700 | [diff] [blame] | 2143 | * nr_pages that have not been attempted as |
| 2144 | * well. |
| 2145 | */ |
| 2146 | if (err > 0) |
Huang Ying | a7504ed | 2022-08-17 16:14:01 +0800 | [diff] [blame] | 2147 | err += nr_pages - i; |
Wei Yang | 7ca8783 | 2020-04-06 20:04:12 -0700 | [diff] [blame] | 2148 | return err; |
| 2149 | } |
| 2150 | return store_status(status, start, node, i - start); |
| 2151 | } |
| 2152 | |
Christoph Lameter | 742755a | 2006-06-23 02:03:55 -0700 | [diff] [blame] | 2153 | /* |
Brice Goglin | 5e9a0f0 | 2008-10-18 20:27:17 -0700 | [diff] [blame] | 2154 | * Migrate an array of page address onto an array of nodes and fill |
| 2155 | * the corresponding array of status. |
| 2156 | */ |
Christoph Lameter | 3268c63 | 2012-03-21 16:34:06 -0700 | [diff] [blame] | 2157 | static int do_pages_move(struct mm_struct *mm, nodemask_t task_nodes, |
Brice Goglin | 5e9a0f0 | 2008-10-18 20:27:17 -0700 | [diff] [blame] | 2158 | unsigned long nr_pages, |
| 2159 | const void __user * __user *pages, |
| 2160 | const int __user *nodes, |
| 2161 | int __user *status, int flags) |
| 2162 | { |
Michal Hocko | a49bd4d | 2018-04-10 16:29:59 -0700 | [diff] [blame] | 2163 | int current_node = NUMA_NO_NODE; |
| 2164 | LIST_HEAD(pagelist); |
| 2165 | int start, i; |
| 2166 | int err = 0, err1; |
Brice Goglin | 35282a2 | 2009-06-16 15:32:43 -0700 | [diff] [blame] | 2167 | |
Minchan Kim | 361a2a2 | 2021-05-04 18:36:57 -0700 | [diff] [blame] | 2168 | lru_cache_disable(); |
Brice Goglin | 35282a2 | 2009-06-16 15:32:43 -0700 | [diff] [blame] | 2169 | |
Michal Hocko | a49bd4d | 2018-04-10 16:29:59 -0700 | [diff] [blame] | 2170 | for (i = start = 0; i < nr_pages; i++) { |
| 2171 | const void __user *p; |
Michal Hocko | a49bd4d | 2018-04-10 16:29:59 -0700 | [diff] [blame] | 2172 | int node; |
Brice Goglin | 5e9a0f0 | 2008-10-18 20:27:17 -0700 | [diff] [blame] | 2173 | |
Michal Hocko | a49bd4d | 2018-04-10 16:29:59 -0700 | [diff] [blame] | 2174 | err = -EFAULT; |
| 2175 | if (get_user(p, pages + i)) |
| 2176 | goto out_flush; |
| 2177 | if (get_user(node, nodes + i)) |
| 2178 | goto out_flush; |
Brice Goglin | 5e9a0f0 | 2008-10-18 20:27:17 -0700 | [diff] [blame] | 2179 | |
Michal Hocko | a49bd4d | 2018-04-10 16:29:59 -0700 | [diff] [blame] | 2180 | err = -ENODEV; |
| 2181 | if (node < 0 || node >= MAX_NUMNODES) |
| 2182 | goto out_flush; |
| 2183 | if (!node_state(node, N_MEMORY)) |
| 2184 | goto out_flush; |
Brice Goglin | 3140a22 | 2009-01-06 14:38:57 -0800 | [diff] [blame] | 2185 | |
Michal Hocko | a49bd4d | 2018-04-10 16:29:59 -0700 | [diff] [blame] | 2186 | err = -EACCES; |
| 2187 | if (!node_isset(node, task_nodes)) |
| 2188 | goto out_flush; |
Brice Goglin | 5e9a0f0 | 2008-10-18 20:27:17 -0700 | [diff] [blame] | 2189 | |
Michal Hocko | a49bd4d | 2018-04-10 16:29:59 -0700 | [diff] [blame] | 2190 | if (current_node == NUMA_NO_NODE) { |
| 2191 | current_node = node; |
| 2192 | start = i; |
| 2193 | } else if (node != current_node) { |
Wei Yang | 7ca8783 | 2020-04-06 20:04:12 -0700 | [diff] [blame] | 2194 | err = move_pages_and_store_status(mm, current_node, |
| 2195 | &pagelist, status, start, i, nr_pages); |
Michal Hocko | a49bd4d | 2018-04-10 16:29:59 -0700 | [diff] [blame] | 2196 | if (err) |
| 2197 | goto out; |
| 2198 | start = i; |
| 2199 | current_node = node; |
Brice Goglin | 3140a22 | 2009-01-06 14:38:57 -0800 | [diff] [blame] | 2200 | } |
Brice Goglin | 5e9a0f0 | 2008-10-18 20:27:17 -0700 | [diff] [blame] | 2201 | |
Michal Hocko | a49bd4d | 2018-04-10 16:29:59 -0700 | [diff] [blame] | 2202 | /* |
| 2203 | * Errors in the page lookup or isolation are not fatal and we simply |
| 2204 | * report them via status |
| 2205 | */ |
Kirill A. Shutemov | 428e106 | 2023-03-12 14:26:00 +0300 | [diff] [blame] | 2206 | err = add_page_for_migration(mm, p, current_node, &pagelist, |
| 2207 | flags & MPOL_MF_MOVE_ALL); |
Yang Shi | e0153fc | 2020-01-04 12:59:46 -0800 | [diff] [blame] | 2208 | |
Wei Yang | d08221a | 2020-04-06 20:04:18 -0700 | [diff] [blame] | 2209 | if (err > 0) { |
Yang Shi | e0153fc | 2020-01-04 12:59:46 -0800 | [diff] [blame] | 2210 | /* The page is successfully queued for migration */ |
| 2211 | continue; |
| 2212 | } |
Brice Goglin | 3140a22 | 2009-01-06 14:38:57 -0800 | [diff] [blame] | 2213 | |
Wei Yang | d08221a | 2020-04-06 20:04:18 -0700 | [diff] [blame] | 2214 | /* |
John Hubbard | 6546246 | 2022-03-22 14:39:40 -0700 | [diff] [blame] | 2215 | * The move_pages() man page does not have an -EEXIST choice, so |
| 2216 | * use -EFAULT instead. |
| 2217 | */ |
| 2218 | if (err == -EEXIST) |
| 2219 | err = -EFAULT; |
| 2220 | |
| 2221 | /* |
Wei Yang | d08221a | 2020-04-06 20:04:18 -0700 | [diff] [blame] | 2222 | * If the page is already on the target node (!err), store the |
| 2223 | * node, otherwise, store the err. |
| 2224 | */ |
| 2225 | err = store_status(status, i, err ? : current_node, 1); |
Michal Hocko | a49bd4d | 2018-04-10 16:29:59 -0700 | [diff] [blame] | 2226 | if (err) |
| 2227 | goto out_flush; |
Brice Goglin | 3140a22 | 2009-01-06 14:38:57 -0800 | [diff] [blame] | 2228 | |
Wei Yang | 7ca8783 | 2020-04-06 20:04:12 -0700 | [diff] [blame] | 2229 | err = move_pages_and_store_status(mm, current_node, &pagelist, |
| 2230 | status, start, i, nr_pages); |
Huang Ying | a7504ed | 2022-08-17 16:14:01 +0800 | [diff] [blame] | 2231 | if (err) { |
| 2232 | /* We have accounted for page i */ |
| 2233 | if (err > 0) |
| 2234 | err--; |
Wei Yang | 4afdace | 2020-04-06 20:04:09 -0700 | [diff] [blame] | 2235 | goto out; |
Huang Ying | a7504ed | 2022-08-17 16:14:01 +0800 | [diff] [blame] | 2236 | } |
Michal Hocko | a49bd4d | 2018-04-10 16:29:59 -0700 | [diff] [blame] | 2237 | current_node = NUMA_NO_NODE; |
Brice Goglin | 3140a22 | 2009-01-06 14:38:57 -0800 | [diff] [blame] | 2238 | } |
Michal Hocko | a49bd4d | 2018-04-10 16:29:59 -0700 | [diff] [blame] | 2239 | out_flush: |
| 2240 | /* Make sure we do not overwrite the existing error */ |
Wei Yang | 7ca8783 | 2020-04-06 20:04:12 -0700 | [diff] [blame] | 2241 | err1 = move_pages_and_store_status(mm, current_node, &pagelist, |
| 2242 | status, start, i, nr_pages); |
Wei Yang | dfe9aa2 | 2020-01-30 22:11:14 -0800 | [diff] [blame] | 2243 | if (err >= 0) |
Michal Hocko | a49bd4d | 2018-04-10 16:29:59 -0700 | [diff] [blame] | 2244 | err = err1; |
Brice Goglin | 5e9a0f0 | 2008-10-18 20:27:17 -0700 | [diff] [blame] | 2245 | out: |
Minchan Kim | 361a2a2 | 2021-05-04 18:36:57 -0700 | [diff] [blame] | 2246 | lru_cache_enable(); |
Brice Goglin | 5e9a0f0 | 2008-10-18 20:27:17 -0700 | [diff] [blame] | 2247 | return err; |
| 2248 | } |
| 2249 | |
| 2250 | /* |
Brice Goglin | 2f007e7 | 2008-10-18 20:27:16 -0700 | [diff] [blame] | 2251 | * Determine the nodes of an array of pages and store it in an array of status. |
Christoph Lameter | 742755a | 2006-06-23 02:03:55 -0700 | [diff] [blame] | 2252 | */ |
Brice Goglin | 80bba12 | 2008-12-09 13:14:23 -0800 | [diff] [blame] | 2253 | static void do_pages_stat_array(struct mm_struct *mm, unsigned long nr_pages, |
| 2254 | const void __user **pages, int *status) |
Christoph Lameter | 742755a | 2006-06-23 02:03:55 -0700 | [diff] [blame] | 2255 | { |
Brice Goglin | 2f007e7 | 2008-10-18 20:27:16 -0700 | [diff] [blame] | 2256 | unsigned long i; |
Brice Goglin | 2f007e7 | 2008-10-18 20:27:16 -0700 | [diff] [blame] | 2257 | |
Michel Lespinasse | d8ed45c | 2020-06-08 21:33:25 -0700 | [diff] [blame] | 2258 | mmap_read_lock(mm); |
Christoph Lameter | 742755a | 2006-06-23 02:03:55 -0700 | [diff] [blame] | 2259 | |
Brice Goglin | 2f007e7 | 2008-10-18 20:27:16 -0700 | [diff] [blame] | 2260 | for (i = 0; i < nr_pages; i++) { |
Brice Goglin | 80bba12 | 2008-12-09 13:14:23 -0800 | [diff] [blame] | 2261 | unsigned long addr = (unsigned long)(*pages); |
Christoph Lameter | 742755a | 2006-06-23 02:03:55 -0700 | [diff] [blame] | 2262 | struct vm_area_struct *vma; |
| 2263 | struct page *page; |
KOSAKI Motohiro | c095adb | 2008-12-16 16:06:43 +0900 | [diff] [blame] | 2264 | int err = -EFAULT; |
Brice Goglin | 2f007e7 | 2008-10-18 20:27:16 -0700 | [diff] [blame] | 2265 | |
Liam Howlett | 059b8b4 | 2021-06-28 19:39:44 -0700 | [diff] [blame] | 2266 | vma = vma_lookup(mm, addr); |
| 2267 | if (!vma) |
Christoph Lameter | 742755a | 2006-06-23 02:03:55 -0700 | [diff] [blame] | 2268 | goto set_status; |
| 2269 | |
Kirill A. Shutemov | d899844 | 2015-09-04 15:47:53 -0700 | [diff] [blame] | 2270 | /* FOLL_DUMP to ignore special (like zero) pages */ |
Baolin Wang | 16fd6b3 | 2022-11-09 16:40:27 +0800 | [diff] [blame] | 2271 | page = follow_page(vma, addr, FOLL_GET | FOLL_DUMP); |
Linus Torvalds | 89f5b7d | 2008-06-20 11:18:25 -0700 | [diff] [blame] | 2272 | |
| 2273 | err = PTR_ERR(page); |
| 2274 | if (IS_ERR(page)) |
| 2275 | goto set_status; |
| 2276 | |
Haiyue Wang | f7091ed | 2022-08-23 21:58:41 +0800 | [diff] [blame] | 2277 | err = -ENOENT; |
| 2278 | if (!page) |
| 2279 | goto set_status; |
| 2280 | |
| 2281 | if (!is_zone_device_page(page)) |
Miaohe Lin | 4cd6148 | 2022-04-28 23:16:08 -0700 | [diff] [blame] | 2282 | err = page_to_nid(page); |
Haiyue Wang | f7091ed | 2022-08-23 21:58:41 +0800 | [diff] [blame] | 2283 | |
Baolin Wang | 16fd6b3 | 2022-11-09 16:40:27 +0800 | [diff] [blame] | 2284 | put_page(page); |
Christoph Lameter | 742755a | 2006-06-23 02:03:55 -0700 | [diff] [blame] | 2285 | set_status: |
Brice Goglin | 80bba12 | 2008-12-09 13:14:23 -0800 | [diff] [blame] | 2286 | *status = err; |
| 2287 | |
| 2288 | pages++; |
| 2289 | status++; |
| 2290 | } |
| 2291 | |
Michel Lespinasse | d8ed45c | 2020-06-08 21:33:25 -0700 | [diff] [blame] | 2292 | mmap_read_unlock(mm); |
Brice Goglin | 80bba12 | 2008-12-09 13:14:23 -0800 | [diff] [blame] | 2293 | } |
| 2294 | |
Arnd Bergmann | 5b1b561 | 2021-09-08 15:18:17 -0700 | [diff] [blame] | 2295 | static int get_compat_pages_array(const void __user *chunk_pages[], |
| 2296 | const void __user * __user *pages, |
| 2297 | unsigned long chunk_nr) |
| 2298 | { |
| 2299 | compat_uptr_t __user *pages32 = (compat_uptr_t __user *)pages; |
| 2300 | compat_uptr_t p; |
| 2301 | int i; |
| 2302 | |
| 2303 | for (i = 0; i < chunk_nr; i++) { |
| 2304 | if (get_user(p, pages32 + i)) |
| 2305 | return -EFAULT; |
| 2306 | chunk_pages[i] = compat_ptr(p); |
| 2307 | } |
| 2308 | |
| 2309 | return 0; |
| 2310 | } |
| 2311 | |
Brice Goglin | 80bba12 | 2008-12-09 13:14:23 -0800 | [diff] [blame] | 2312 | /* |
| 2313 | * Determine the nodes of a user array of pages and store it in |
| 2314 | * a user array of status. |
| 2315 | */ |
| 2316 | static int do_pages_stat(struct mm_struct *mm, unsigned long nr_pages, |
| 2317 | const void __user * __user *pages, |
| 2318 | int __user *status) |
| 2319 | { |
Miaohe Lin | 3eefb82 | 2022-04-28 23:16:07 -0700 | [diff] [blame] | 2320 | #define DO_PAGES_STAT_CHUNK_NR 16UL |
Brice Goglin | 80bba12 | 2008-12-09 13:14:23 -0800 | [diff] [blame] | 2321 | const void __user *chunk_pages[DO_PAGES_STAT_CHUNK_NR]; |
| 2322 | int chunk_status[DO_PAGES_STAT_CHUNK_NR]; |
Brice Goglin | 80bba12 | 2008-12-09 13:14:23 -0800 | [diff] [blame] | 2323 | |
H. Peter Anvin | 87b8d1a | 2010-02-18 16:13:40 -0800 | [diff] [blame] | 2324 | while (nr_pages) { |
Miaohe Lin | 3eefb82 | 2022-04-28 23:16:07 -0700 | [diff] [blame] | 2325 | unsigned long chunk_nr = min(nr_pages, DO_PAGES_STAT_CHUNK_NR); |
H. Peter Anvin | 87b8d1a | 2010-02-18 16:13:40 -0800 | [diff] [blame] | 2326 | |
Arnd Bergmann | 5b1b561 | 2021-09-08 15:18:17 -0700 | [diff] [blame] | 2327 | if (in_compat_syscall()) { |
| 2328 | if (get_compat_pages_array(chunk_pages, pages, |
| 2329 | chunk_nr)) |
| 2330 | break; |
| 2331 | } else { |
| 2332 | if (copy_from_user(chunk_pages, pages, |
| 2333 | chunk_nr * sizeof(*chunk_pages))) |
| 2334 | break; |
| 2335 | } |
Brice Goglin | 80bba12 | 2008-12-09 13:14:23 -0800 | [diff] [blame] | 2336 | |
| 2337 | do_pages_stat_array(mm, chunk_nr, chunk_pages, chunk_status); |
| 2338 | |
H. Peter Anvin | 87b8d1a | 2010-02-18 16:13:40 -0800 | [diff] [blame] | 2339 | if (copy_to_user(status, chunk_status, chunk_nr * sizeof(*status))) |
| 2340 | break; |
Christoph Lameter | 742755a | 2006-06-23 02:03:55 -0700 | [diff] [blame] | 2341 | |
H. Peter Anvin | 87b8d1a | 2010-02-18 16:13:40 -0800 | [diff] [blame] | 2342 | pages += chunk_nr; |
| 2343 | status += chunk_nr; |
| 2344 | nr_pages -= chunk_nr; |
| 2345 | } |
| 2346 | return nr_pages ? -EFAULT : 0; |
Christoph Lameter | 742755a | 2006-06-23 02:03:55 -0700 | [diff] [blame] | 2347 | } |
| 2348 | |
Miaohe Lin | 4dc200c | 2020-10-17 16:14:03 -0700 | [diff] [blame] | 2349 | static struct mm_struct *find_mm_struct(pid_t pid, nodemask_t *mem_nodes) |
| 2350 | { |
| 2351 | struct task_struct *task; |
| 2352 | struct mm_struct *mm; |
| 2353 | |
| 2354 | /* |
| 2355 | * There is no need to check if current process has the right to modify |
| 2356 | * the specified process when they are same. |
| 2357 | */ |
| 2358 | if (!pid) { |
| 2359 | mmget(current->mm); |
| 2360 | *mem_nodes = cpuset_mems_allowed(current); |
| 2361 | return current->mm; |
| 2362 | } |
| 2363 | |
| 2364 | /* Find the mm_struct */ |
| 2365 | rcu_read_lock(); |
| 2366 | task = find_task_by_vpid(pid); |
| 2367 | if (!task) { |
| 2368 | rcu_read_unlock(); |
| 2369 | return ERR_PTR(-ESRCH); |
| 2370 | } |
| 2371 | get_task_struct(task); |
| 2372 | |
| 2373 | /* |
| 2374 | * Check if this process has the right to modify the specified |
| 2375 | * process. Use the regular "ptrace_may_access()" checks. |
| 2376 | */ |
| 2377 | if (!ptrace_may_access(task, PTRACE_MODE_READ_REALCREDS)) { |
| 2378 | rcu_read_unlock(); |
| 2379 | mm = ERR_PTR(-EPERM); |
| 2380 | goto out; |
| 2381 | } |
| 2382 | rcu_read_unlock(); |
| 2383 | |
| 2384 | mm = ERR_PTR(security_task_movememory(task)); |
| 2385 | if (IS_ERR(mm)) |
| 2386 | goto out; |
| 2387 | *mem_nodes = cpuset_mems_allowed(task); |
| 2388 | mm = get_task_mm(task); |
| 2389 | out: |
| 2390 | put_task_struct(task); |
| 2391 | if (!mm) |
| 2392 | mm = ERR_PTR(-EINVAL); |
| 2393 | return mm; |
| 2394 | } |
| 2395 | |
Christoph Lameter | 742755a | 2006-06-23 02:03:55 -0700 | [diff] [blame] | 2396 | /* |
| 2397 | * Move a list of pages in the address space of the currently executing |
| 2398 | * process. |
| 2399 | */ |
Dominik Brodowski | 7addf44 | 2018-03-17 16:08:03 +0100 | [diff] [blame] | 2400 | static int kernel_move_pages(pid_t pid, unsigned long nr_pages, |
| 2401 | const void __user * __user *pages, |
| 2402 | const int __user *nodes, |
| 2403 | int __user *status, int flags) |
Christoph Lameter | 742755a | 2006-06-23 02:03:55 -0700 | [diff] [blame] | 2404 | { |
Christoph Lameter | 742755a | 2006-06-23 02:03:55 -0700 | [diff] [blame] | 2405 | struct mm_struct *mm; |
Brice Goglin | 5e9a0f0 | 2008-10-18 20:27:17 -0700 | [diff] [blame] | 2406 | int err; |
Christoph Lameter | 3268c63 | 2012-03-21 16:34:06 -0700 | [diff] [blame] | 2407 | nodemask_t task_nodes; |
Christoph Lameter | 742755a | 2006-06-23 02:03:55 -0700 | [diff] [blame] | 2408 | |
| 2409 | /* Check flags */ |
| 2410 | if (flags & ~(MPOL_MF_MOVE|MPOL_MF_MOVE_ALL)) |
| 2411 | return -EINVAL; |
| 2412 | |
| 2413 | if ((flags & MPOL_MF_MOVE_ALL) && !capable(CAP_SYS_NICE)) |
| 2414 | return -EPERM; |
| 2415 | |
Miaohe Lin | 4dc200c | 2020-10-17 16:14:03 -0700 | [diff] [blame] | 2416 | mm = find_mm_struct(pid, &task_nodes); |
| 2417 | if (IS_ERR(mm)) |
| 2418 | return PTR_ERR(mm); |
Sasha Levin | 6e8b09e | 2012-04-25 16:01:53 -0700 | [diff] [blame] | 2419 | |
| 2420 | if (nodes) |
| 2421 | err = do_pages_move(mm, task_nodes, nr_pages, pages, |
| 2422 | nodes, status, flags); |
| 2423 | else |
| 2424 | err = do_pages_stat(mm, nr_pages, pages, status); |
Christoph Lameter | 3268c63 | 2012-03-21 16:34:06 -0700 | [diff] [blame] | 2425 | |
| 2426 | mmput(mm); |
| 2427 | return err; |
Christoph Lameter | 742755a | 2006-06-23 02:03:55 -0700 | [diff] [blame] | 2428 | } |
Christoph Lameter | 742755a | 2006-06-23 02:03:55 -0700 | [diff] [blame] | 2429 | |
Dominik Brodowski | 7addf44 | 2018-03-17 16:08:03 +0100 | [diff] [blame] | 2430 | SYSCALL_DEFINE6(move_pages, pid_t, pid, unsigned long, nr_pages, |
| 2431 | const void __user * __user *, pages, |
| 2432 | const int __user *, nodes, |
| 2433 | int __user *, status, int, flags) |
| 2434 | { |
| 2435 | return kernel_move_pages(pid, nr_pages, pages, nodes, status, flags); |
| 2436 | } |
| 2437 | |
Peter Zijlstra | 7039e1d | 2012-10-25 14:16:34 +0200 | [diff] [blame] | 2438 | #ifdef CONFIG_NUMA_BALANCING |
| 2439 | /* |
| 2440 | * Returns true if this is a safe migration target node for misplaced NUMA |
Wei Yang | bc53008 | 2022-04-28 23:16:03 -0700 | [diff] [blame] | 2441 | * pages. Currently it only checks the watermarks which is crude. |
Peter Zijlstra | 7039e1d | 2012-10-25 14:16:34 +0200 | [diff] [blame] | 2442 | */ |
| 2443 | static bool migrate_balanced_pgdat(struct pglist_data *pgdat, |
Mel Gorman | 3abef4e | 2013-02-22 16:34:27 -0800 | [diff] [blame] | 2444 | unsigned long nr_migrate_pages) |
Peter Zijlstra | 7039e1d | 2012-10-25 14:16:34 +0200 | [diff] [blame] | 2445 | { |
| 2446 | int z; |
Mel Gorman | 599d0c9 | 2016-07-28 15:45:31 -0700 | [diff] [blame] | 2447 | |
Peter Zijlstra | 7039e1d | 2012-10-25 14:16:34 +0200 | [diff] [blame] | 2448 | for (z = pgdat->nr_zones - 1; z >= 0; z--) { |
| 2449 | struct zone *zone = pgdat->node_zones + z; |
| 2450 | |
Wei Yang | bc53008 | 2022-04-28 23:16:03 -0700 | [diff] [blame] | 2451 | if (!managed_zone(zone)) |
Peter Zijlstra | 7039e1d | 2012-10-25 14:16:34 +0200 | [diff] [blame] | 2452 | continue; |
| 2453 | |
Peter Zijlstra | 7039e1d | 2012-10-25 14:16:34 +0200 | [diff] [blame] | 2454 | /* Avoid waking kswapd by allocating pages_to_migrate pages. */ |
| 2455 | if (!zone_watermark_ok(zone, 0, |
| 2456 | high_wmark_pages(zone) + |
| 2457 | nr_migrate_pages, |
Huang Ying | bfe9d00 | 2019-11-30 17:57:28 -0800 | [diff] [blame] | 2458 | ZONE_MOVABLE, 0)) |
Peter Zijlstra | 7039e1d | 2012-10-25 14:16:34 +0200 | [diff] [blame] | 2459 | continue; |
| 2460 | return true; |
| 2461 | } |
| 2462 | return false; |
| 2463 | } |
| 2464 | |
Matthew Wilcox (Oracle) | 4e096ae | 2023-05-13 01:11:01 +0100 | [diff] [blame] | 2465 | static struct folio *alloc_misplaced_dst_folio(struct folio *src, |
Michal Hocko | 666feb2 | 2018-04-10 16:30:03 -0700 | [diff] [blame] | 2466 | unsigned long data) |
Peter Zijlstra | 7039e1d | 2012-10-25 14:16:34 +0200 | [diff] [blame] | 2467 | { |
| 2468 | int nid = (int) data; |
Matthew Wilcox (Oracle) | 4e096ae | 2023-05-13 01:11:01 +0100 | [diff] [blame] | 2469 | int order = folio_order(src); |
Matthew Wilcox (Oracle) | c185e49 | 2021-07-06 10:50:39 -0400 | [diff] [blame] | 2470 | gfp_t gfp = __GFP_THISNODE; |
Peter Zijlstra | 7039e1d | 2012-10-25 14:16:34 +0200 | [diff] [blame] | 2471 | |
Matthew Wilcox (Oracle) | c185e49 | 2021-07-06 10:50:39 -0400 | [diff] [blame] | 2472 | if (order > 0) |
| 2473 | gfp |= GFP_TRANSHUGE_LIGHT; |
| 2474 | else { |
| 2475 | gfp |= GFP_HIGHUSER_MOVABLE | __GFP_NOMEMALLOC | __GFP_NORETRY | |
| 2476 | __GFP_NOWARN; |
| 2477 | gfp &= ~__GFP_RECLAIM; |
| 2478 | } |
Matthew Wilcox (Oracle) | 4e096ae | 2023-05-13 01:11:01 +0100 | [diff] [blame] | 2479 | return __folio_alloc_node(gfp, order, nid); |
Yang Shi | c5b5a3d | 2021-06-30 18:51:42 -0700 | [diff] [blame] | 2480 | } |
| 2481 | |
Mel Gorman | 1c30e01 | 2014-01-21 15:50:58 -0800 | [diff] [blame] | 2482 | static int numamigrate_isolate_page(pg_data_t *pgdat, struct page *page) |
Mel Gorman | b32967f | 2012-11-19 12:35:47 +0000 | [diff] [blame] | 2483 | { |
Baolin Wang | 2b9b624 | 2021-09-08 15:18:01 -0700 | [diff] [blame] | 2484 | int nr_pages = thp_nr_pages(page); |
Huang Ying | c574bbe | 2022-03-22 14:46:23 -0700 | [diff] [blame] | 2485 | int order = compound_order(page); |
Mel Gorman | b32967f | 2012-11-19 12:35:47 +0000 | [diff] [blame] | 2486 | |
Huang Ying | c574bbe | 2022-03-22 14:46:23 -0700 | [diff] [blame] | 2487 | VM_BUG_ON_PAGE(order && !PageTransHuge(page), page); |
Mel Gorman | 3abef4e | 2013-02-22 16:34:27 -0800 | [diff] [blame] | 2488 | |
Yang Shi | 662aeea | 2021-06-30 18:51:51 -0700 | [diff] [blame] | 2489 | /* Do not migrate THP mapped by multiple processes */ |
| 2490 | if (PageTransHuge(page) && total_mapcount(page) > 1) |
| 2491 | return 0; |
| 2492 | |
Mel Gorman | b32967f | 2012-11-19 12:35:47 +0000 | [diff] [blame] | 2493 | /* Avoid migrating to a node that is nearly full */ |
Huang Ying | c574bbe | 2022-03-22 14:46:23 -0700 | [diff] [blame] | 2494 | if (!migrate_balanced_pgdat(pgdat, nr_pages)) { |
| 2495 | int z; |
| 2496 | |
| 2497 | if (!(sysctl_numa_balancing_mode & NUMA_BALANCING_MEMORY_TIERING)) |
| 2498 | return 0; |
| 2499 | for (z = pgdat->nr_zones - 1; z >= 0; z--) { |
Wei Yang | bc53008 | 2022-04-28 23:16:03 -0700 | [diff] [blame] | 2500 | if (managed_zone(pgdat->node_zones + z)) |
Huang Ying | c574bbe | 2022-03-22 14:46:23 -0700 | [diff] [blame] | 2501 | break; |
| 2502 | } |
| 2503 | wakeup_kswapd(pgdat->node_zones + z, 0, order, ZONE_MOVABLE); |
Hugh Dickins | 340ef39 | 2013-02-22 16:34:33 -0800 | [diff] [blame] | 2504 | return 0; |
Huang Ying | c574bbe | 2022-03-22 14:46:23 -0700 | [diff] [blame] | 2505 | } |
Mel Gorman | b32967f | 2012-11-19 12:35:47 +0000 | [diff] [blame] | 2506 | |
Baolin Wang | f7f9c00 | 2023-02-15 18:39:35 +0800 | [diff] [blame] | 2507 | if (!isolate_lru_page(page)) |
Hugh Dickins | 340ef39 | 2013-02-22 16:34:33 -0800 | [diff] [blame] | 2508 | return 0; |
Mel Gorman | b32967f | 2012-11-19 12:35:47 +0000 | [diff] [blame] | 2509 | |
Miaohe Lin | b75454e | 2022-04-28 23:16:07 -0700 | [diff] [blame] | 2510 | mod_node_page_state(page_pgdat(page), NR_ISOLATED_ANON + page_is_file_lru(page), |
Baolin Wang | 2b9b624 | 2021-09-08 15:18:01 -0700 | [diff] [blame] | 2511 | nr_pages); |
Hugh Dickins | 340ef39 | 2013-02-22 16:34:33 -0800 | [diff] [blame] | 2512 | |
| 2513 | /* |
| 2514 | * Isolating the page has taken another reference, so the |
| 2515 | * caller's reference can be safely dropped without the page |
| 2516 | * disappearing underneath us during migration. |
Mel Gorman | b32967f | 2012-11-19 12:35:47 +0000 | [diff] [blame] | 2517 | */ |
| 2518 | put_page(page); |
Hugh Dickins | 340ef39 | 2013-02-22 16:34:33 -0800 | [diff] [blame] | 2519 | return 1; |
Mel Gorman | b32967f | 2012-11-19 12:35:47 +0000 | [diff] [blame] | 2520 | } |
| 2521 | |
Mel Gorman | a8f6077 | 2012-11-14 21:41:46 +0000 | [diff] [blame] | 2522 | /* |
Peter Zijlstra | 7039e1d | 2012-10-25 14:16:34 +0200 | [diff] [blame] | 2523 | * Attempt to migrate a misplaced page to the specified destination |
| 2524 | * node. Caller is expected to have an elevated reference count on |
| 2525 | * the page that will be dropped by this function before returning. |
| 2526 | */ |
Mel Gorman | 1bc115d | 2013-10-07 11:29:05 +0100 | [diff] [blame] | 2527 | int migrate_misplaced_page(struct page *page, struct vm_area_struct *vma, |
| 2528 | int node) |
Peter Zijlstra | 7039e1d | 2012-10-25 14:16:34 +0200 | [diff] [blame] | 2529 | { |
Mel Gorman | a8f6077 | 2012-11-14 21:41:46 +0000 | [diff] [blame] | 2530 | pg_data_t *pgdat = NODE_DATA(node); |
Hugh Dickins | 340ef39 | 2013-02-22 16:34:33 -0800 | [diff] [blame] | 2531 | int isolated; |
Mel Gorman | b32967f | 2012-11-19 12:35:47 +0000 | [diff] [blame] | 2532 | int nr_remaining; |
Huang Ying | e39bb6b | 2022-03-22 14:46:20 -0700 | [diff] [blame] | 2533 | unsigned int nr_succeeded; |
Peter Zijlstra | 7039e1d | 2012-10-25 14:16:34 +0200 | [diff] [blame] | 2534 | LIST_HEAD(migratepages); |
Aneesh Kumar K.V | b5916c0 | 2021-07-29 14:53:47 -0700 | [diff] [blame] | 2535 | int nr_pages = thp_nr_pages(page); |
Yang Shi | c5b5a3d | 2021-06-30 18:51:42 -0700 | [diff] [blame] | 2536 | |
| 2537 | /* |
Mel Gorman | 1bc115d | 2013-10-07 11:29:05 +0100 | [diff] [blame] | 2538 | * Don't migrate file pages that are mapped in multiple processes |
| 2539 | * with execute permissions as they are probably shared libraries. |
Peter Zijlstra | 7039e1d | 2012-10-25 14:16:34 +0200 | [diff] [blame] | 2540 | */ |
Miaohe Lin | 7ee820e | 2021-05-04 18:37:16 -0700 | [diff] [blame] | 2541 | if (page_mapcount(page) != 1 && page_is_file_lru(page) && |
| 2542 | (vma->vm_flags & VM_EXEC)) |
Peter Zijlstra | 7039e1d | 2012-10-25 14:16:34 +0200 | [diff] [blame] | 2543 | goto out; |
Peter Zijlstra | 7039e1d | 2012-10-25 14:16:34 +0200 | [diff] [blame] | 2544 | |
Mel Gorman | a8f6077 | 2012-11-14 21:41:46 +0000 | [diff] [blame] | 2545 | /* |
Mel Gorman | 09a913a | 2018-04-10 16:29:20 -0700 | [diff] [blame] | 2546 | * Also do not migrate dirty pages as not all filesystems can move |
| 2547 | * dirty pages in MIGRATE_ASYNC mode which is a waste of cycles. |
| 2548 | */ |
Huang Ying | 9de4f22 | 2020-04-06 20:04:41 -0700 | [diff] [blame] | 2549 | if (page_is_file_lru(page) && PageDirty(page)) |
Mel Gorman | 09a913a | 2018-04-10 16:29:20 -0700 | [diff] [blame] | 2550 | goto out; |
| 2551 | |
Mel Gorman | b32967f | 2012-11-19 12:35:47 +0000 | [diff] [blame] | 2552 | isolated = numamigrate_isolate_page(pgdat, page); |
| 2553 | if (!isolated) |
| 2554 | goto out; |
Peter Zijlstra | 7039e1d | 2012-10-25 14:16:34 +0200 | [diff] [blame] | 2555 | |
Mel Gorman | b32967f | 2012-11-19 12:35:47 +0000 | [diff] [blame] | 2556 | list_add(&page->lru, &migratepages); |
Matthew Wilcox (Oracle) | 4e096ae | 2023-05-13 01:11:01 +0100 | [diff] [blame] | 2557 | nr_remaining = migrate_pages(&migratepages, alloc_misplaced_dst_folio, |
Matthew Wilcox (Oracle) | c185e49 | 2021-07-06 10:50:39 -0400 | [diff] [blame] | 2558 | NULL, node, MIGRATE_ASYNC, |
| 2559 | MR_NUMA_MISPLACED, &nr_succeeded); |
Mel Gorman | b32967f | 2012-11-19 12:35:47 +0000 | [diff] [blame] | 2560 | if (nr_remaining) { |
Joonsoo Kim | 59c82b7 | 2014-01-21 15:51:17 -0800 | [diff] [blame] | 2561 | if (!list_empty(&migratepages)) { |
| 2562 | list_del(&page->lru); |
Yang Shi | c5fc5c3 | 2021-06-30 18:51:45 -0700 | [diff] [blame] | 2563 | mod_node_page_state(page_pgdat(page), NR_ISOLATED_ANON + |
| 2564 | page_is_file_lru(page), -nr_pages); |
Joonsoo Kim | 59c82b7 | 2014-01-21 15:51:17 -0800 | [diff] [blame] | 2565 | putback_lru_page(page); |
| 2566 | } |
Mel Gorman | b32967f | 2012-11-19 12:35:47 +0000 | [diff] [blame] | 2567 | isolated = 0; |
Huang Ying | e39bb6b | 2022-03-22 14:46:20 -0700 | [diff] [blame] | 2568 | } |
| 2569 | if (nr_succeeded) { |
| 2570 | count_vm_numa_events(NUMA_PAGE_MIGRATE, nr_succeeded); |
| 2571 | if (!node_is_toptier(page_to_nid(page)) && node_is_toptier(node)) |
| 2572 | mod_node_page_state(pgdat, PGPROMOTE_SUCCESS, |
| 2573 | nr_succeeded); |
| 2574 | } |
Peter Zijlstra | 7039e1d | 2012-10-25 14:16:34 +0200 | [diff] [blame] | 2575 | BUG_ON(!list_empty(&migratepages)); |
Peter Zijlstra | 7039e1d | 2012-10-25 14:16:34 +0200 | [diff] [blame] | 2576 | return isolated; |
Hugh Dickins | 340ef39 | 2013-02-22 16:34:33 -0800 | [diff] [blame] | 2577 | |
| 2578 | out: |
| 2579 | put_page(page); |
| 2580 | return 0; |
Peter Zijlstra | 7039e1d | 2012-10-25 14:16:34 +0200 | [diff] [blame] | 2581 | } |
Mel Gorman | 220018d | 2012-12-05 09:32:56 +0000 | [diff] [blame] | 2582 | #endif /* CONFIG_NUMA_BALANCING */ |
Oscar Salvador | 7d6e2d9 | 2022-04-28 23:16:09 -0700 | [diff] [blame] | 2583 | #endif /* CONFIG_NUMA */ |