Greg Kroah-Hartman | b244131 | 2017-11-01 15:07:57 +0100 | [diff] [blame] | 1 | // SPDX-License-Identifier: GPL-2.0 |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2 | /* |
| 3 | * linux/mm/mlock.c |
| 4 | * |
| 5 | * (C) Copyright 1995 Linus Torvalds |
| 6 | * (C) Copyright 2002 Christoph Hellwig |
| 7 | */ |
| 8 | |
Randy.Dunlap | c59ede7 | 2006-01-11 12:17:46 -0800 | [diff] [blame] | 9 | #include <linux/capability.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 10 | #include <linux/mman.h> |
| 11 | #include <linux/mm.h> |
Ingo Molnar | 8703e8a | 2017-02-08 18:51:30 +0100 | [diff] [blame] | 12 | #include <linux/sched/user.h> |
Nick Piggin | b291f00 | 2008-10-18 20:26:44 -0700 | [diff] [blame] | 13 | #include <linux/swap.h> |
| 14 | #include <linux/swapops.h> |
| 15 | #include <linux/pagemap.h> |
Vlastimil Babka | 7225522 | 2013-09-11 14:22:29 -0700 | [diff] [blame] | 16 | #include <linux/pagevec.h> |
Hugh Dickins | 34b6792 | 2022-02-14 18:31:48 -0800 | [diff] [blame] | 17 | #include <linux/pagewalk.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 18 | #include <linux/mempolicy.h> |
| 19 | #include <linux/syscalls.h> |
Alexey Dobriyan | e8edc6e | 2007-05-21 01:22:52 +0400 | [diff] [blame] | 20 | #include <linux/sched.h> |
Paul Gortmaker | b95f1b31 | 2011-10-16 02:01:52 -0400 | [diff] [blame] | 21 | #include <linux/export.h> |
Nick Piggin | b291f00 | 2008-10-18 20:26:44 -0700 | [diff] [blame] | 22 | #include <linux/rmap.h> |
| 23 | #include <linux/mmzone.h> |
| 24 | #include <linux/hugetlb.h> |
Vlastimil Babka | 7225522 | 2013-09-11 14:22:29 -0700 | [diff] [blame] | 25 | #include <linux/memcontrol.h> |
| 26 | #include <linux/mm_inline.h> |
Mike Rapoport | 1507f51 | 2021-07-07 18:08:03 -0700 | [diff] [blame] | 27 | #include <linux/secretmem.h> |
Nick Piggin | b291f00 | 2008-10-18 20:26:44 -0700 | [diff] [blame] | 28 | |
| 29 | #include "internal.h" |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 30 | |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 31 | struct mlock_fbatch { |
Sebastian Andrzej Siewior | adb11e7 | 2022-04-01 11:28:33 -0700 | [diff] [blame] | 32 | local_lock_t lock; |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 33 | struct folio_batch fbatch; |
Sebastian Andrzej Siewior | adb11e7 | 2022-04-01 11:28:33 -0700 | [diff] [blame] | 34 | }; |
| 35 | |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 36 | static DEFINE_PER_CPU(struct mlock_fbatch, mlock_fbatch) = { |
Sebastian Andrzej Siewior | adb11e7 | 2022-04-01 11:28:33 -0700 | [diff] [blame] | 37 | .lock = INIT_LOCAL_LOCK(lock), |
| 38 | }; |
Hugh Dickins | 2fbb0c1 | 2022-02-14 18:37:29 -0800 | [diff] [blame] | 39 | |
Wang Xiaoqiang | 7f43add | 2016-01-15 16:57:22 -0800 | [diff] [blame] | 40 | bool can_do_mlock(void) |
Alexey Dobriyan | e8edc6e | 2007-05-21 01:22:52 +0400 | [diff] [blame] | 41 | { |
Jiri Slaby | 59e99e5 | 2010-03-05 13:41:44 -0800 | [diff] [blame] | 42 | if (rlimit(RLIMIT_MEMLOCK) != 0) |
Wang Xiaoqiang | 7f43add | 2016-01-15 16:57:22 -0800 | [diff] [blame] | 43 | return true; |
Jeff Vander Stoep | a5a6579 | 2015-03-12 16:26:17 -0700 | [diff] [blame] | 44 | if (capable(CAP_IPC_LOCK)) |
Wang Xiaoqiang | 7f43add | 2016-01-15 16:57:22 -0800 | [diff] [blame] | 45 | return true; |
| 46 | return false; |
Alexey Dobriyan | e8edc6e | 2007-05-21 01:22:52 +0400 | [diff] [blame] | 47 | } |
| 48 | EXPORT_SYMBOL(can_do_mlock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 49 | |
Nick Piggin | b291f00 | 2008-10-18 20:26:44 -0700 | [diff] [blame] | 50 | /* |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 51 | * Mlocked folios are marked with the PG_mlocked flag for efficient testing |
Nick Piggin | b291f00 | 2008-10-18 20:26:44 -0700 | [diff] [blame] | 52 | * in vmscan and, possibly, the fault path; and to support semi-accurate |
| 53 | * statistics. |
| 54 | * |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 55 | * An mlocked folio [folio_test_mlocked(folio)] is unevictable. As such, it |
| 56 | * will be ostensibly placed on the LRU "unevictable" list (actually no such |
| 57 | * list exists), rather than the [in]active lists. PG_unevictable is set to |
| 58 | * indicate the unevictable state. |
Nick Piggin | b291f00 | 2008-10-18 20:26:44 -0700 | [diff] [blame] | 59 | */ |
| 60 | |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 61 | static struct lruvec *__mlock_folio(struct folio *folio, struct lruvec *lruvec) |
Nick Piggin | b291f00 | 2008-10-18 20:26:44 -0700 | [diff] [blame] | 62 | { |
Hugh Dickins | 07ca760 | 2022-02-14 18:29:54 -0800 | [diff] [blame] | 63 | /* There is nothing more we can do while it's off LRU */ |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 64 | if (!folio_test_clear_lru(folio)) |
Hugh Dickins | 2fbb0c1 | 2022-02-14 18:37:29 -0800 | [diff] [blame] | 65 | return lruvec; |
Hugh Dickins | 0964730 | 2020-09-18 21:20:15 -0700 | [diff] [blame] | 66 | |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 67 | lruvec = folio_lruvec_relock_irq(folio, lruvec); |
Nick Piggin | b291f00 | 2008-10-18 20:26:44 -0700 | [diff] [blame] | 68 | |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 69 | if (unlikely(folio_evictable(folio))) { |
Nick Piggin | b291f00 | 2008-10-18 20:26:44 -0700 | [diff] [blame] | 70 | /* |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 71 | * This is a little surprising, but quite possible: PG_mlocked |
| 72 | * must have got cleared already by another CPU. Could this |
| 73 | * folio be unevictable? I'm not sure, but move it now if so. |
Nick Piggin | b291f00 | 2008-10-18 20:26:44 -0700 | [diff] [blame] | 74 | */ |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 75 | if (folio_test_unevictable(folio)) { |
| 76 | lruvec_del_folio(lruvec, folio); |
| 77 | folio_clear_unevictable(folio); |
| 78 | lruvec_add_folio(lruvec, folio); |
| 79 | |
Hugh Dickins | 2fbb0c1 | 2022-02-14 18:37:29 -0800 | [diff] [blame] | 80 | __count_vm_events(UNEVICTABLE_PGRESCUED, |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 81 | folio_nr_pages(folio)); |
Hugh Dickins | 2fbb0c1 | 2022-02-14 18:37:29 -0800 | [diff] [blame] | 82 | } |
| 83 | goto out; |
Nick Piggin | b291f00 | 2008-10-18 20:26:44 -0700 | [diff] [blame] | 84 | } |
Nick Piggin | b291f00 | 2008-10-18 20:26:44 -0700 | [diff] [blame] | 85 | |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 86 | if (folio_test_unevictable(folio)) { |
| 87 | if (folio_test_mlocked(folio)) |
| 88 | folio->mlock_count++; |
Hugh Dickins | 07ca760 | 2022-02-14 18:29:54 -0800 | [diff] [blame] | 89 | goto out; |
Nick Piggin | 5344b7e | 2008-10-18 20:26:51 -0700 | [diff] [blame] | 90 | } |
Hugh Dickins | 07ca760 | 2022-02-14 18:29:54 -0800 | [diff] [blame] | 91 | |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 92 | lruvec_del_folio(lruvec, folio); |
| 93 | folio_clear_active(folio); |
| 94 | folio_set_unevictable(folio); |
| 95 | folio->mlock_count = !!folio_test_mlocked(folio); |
| 96 | lruvec_add_folio(lruvec, folio); |
| 97 | __count_vm_events(UNEVICTABLE_PGCULLED, folio_nr_pages(folio)); |
Hugh Dickins | 07ca760 | 2022-02-14 18:29:54 -0800 | [diff] [blame] | 98 | out: |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 99 | folio_set_lru(folio); |
Hugh Dickins | 2fbb0c1 | 2022-02-14 18:37:29 -0800 | [diff] [blame] | 100 | return lruvec; |
Nick Piggin | b291f00 | 2008-10-18 20:26:44 -0700 | [diff] [blame] | 101 | } |
| 102 | |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 103 | static struct lruvec *__mlock_new_folio(struct folio *folio, struct lruvec *lruvec) |
Vlastimil Babka | 7225522 | 2013-09-11 14:22:29 -0700 | [diff] [blame] | 104 | { |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 105 | VM_BUG_ON_FOLIO(folio_test_lru(folio), folio); |
Vlastimil Babka | 7225522 | 2013-09-11 14:22:29 -0700 | [diff] [blame] | 106 | |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 107 | lruvec = folio_lruvec_relock_irq(folio, lruvec); |
Vlastimil Babka | 7225522 | 2013-09-11 14:22:29 -0700 | [diff] [blame] | 108 | |
Hugh Dickins | 2fbb0c1 | 2022-02-14 18:37:29 -0800 | [diff] [blame] | 109 | /* As above, this is a little surprising, but possible */ |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 110 | if (unlikely(folio_evictable(folio))) |
Hugh Dickins | 2fbb0c1 | 2022-02-14 18:37:29 -0800 | [diff] [blame] | 111 | goto out; |
| 112 | |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 113 | folio_set_unevictable(folio); |
| 114 | folio->mlock_count = !!folio_test_mlocked(folio); |
| 115 | __count_vm_events(UNEVICTABLE_PGCULLED, folio_nr_pages(folio)); |
Hugh Dickins | 2fbb0c1 | 2022-02-14 18:37:29 -0800 | [diff] [blame] | 116 | out: |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 117 | lruvec_add_folio(lruvec, folio); |
| 118 | folio_set_lru(folio); |
Hugh Dickins | 2fbb0c1 | 2022-02-14 18:37:29 -0800 | [diff] [blame] | 119 | return lruvec; |
Vlastimil Babka | 7225522 | 2013-09-11 14:22:29 -0700 | [diff] [blame] | 120 | } |
| 121 | |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 122 | static struct lruvec *__munlock_folio(struct folio *folio, struct lruvec *lruvec) |
Vlastimil Babka | 7225522 | 2013-09-11 14:22:29 -0700 | [diff] [blame] | 123 | { |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 124 | int nr_pages = folio_nr_pages(folio); |
Hugh Dickins | 2fbb0c1 | 2022-02-14 18:37:29 -0800 | [diff] [blame] | 125 | bool isolated = false; |
Hugh Dickins | 0964730 | 2020-09-18 21:20:15 -0700 | [diff] [blame] | 126 | |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 127 | if (!folio_test_clear_lru(folio)) |
Hugh Dickins | 2fbb0c1 | 2022-02-14 18:37:29 -0800 | [diff] [blame] | 128 | goto munlock; |
Kirill A. Shutemov | e90309c | 2016-01-15 16:54:33 -0800 | [diff] [blame] | 129 | |
Hugh Dickins | 2fbb0c1 | 2022-02-14 18:37:29 -0800 | [diff] [blame] | 130 | isolated = true; |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 131 | lruvec = folio_lruvec_relock_irq(folio, lruvec); |
Hugh Dickins | 2fbb0c1 | 2022-02-14 18:37:29 -0800 | [diff] [blame] | 132 | |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 133 | if (folio_test_unevictable(folio)) { |
Hugh Dickins | 07ca760 | 2022-02-14 18:29:54 -0800 | [diff] [blame] | 134 | /* Then mlock_count is maintained, but might undercount */ |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 135 | if (folio->mlock_count) |
| 136 | folio->mlock_count--; |
| 137 | if (folio->mlock_count) |
Hugh Dickins | 07ca760 | 2022-02-14 18:29:54 -0800 | [diff] [blame] | 138 | goto out; |
Vlastimil Babka | 7225522 | 2013-09-11 14:22:29 -0700 | [diff] [blame] | 139 | } |
Hugh Dickins | 07ca760 | 2022-02-14 18:29:54 -0800 | [diff] [blame] | 140 | /* else assume that was the last mlock: reclaim will fix it if not */ |
| 141 | |
Hugh Dickins | 2fbb0c1 | 2022-02-14 18:37:29 -0800 | [diff] [blame] | 142 | munlock: |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 143 | if (folio_test_clear_mlocked(folio)) { |
| 144 | __zone_stat_mod_folio(folio, NR_MLOCK, -nr_pages); |
| 145 | if (isolated || !folio_test_unevictable(folio)) |
Hugh Dickins | 07ca760 | 2022-02-14 18:29:54 -0800 | [diff] [blame] | 146 | __count_vm_events(UNEVICTABLE_PGMUNLOCKED, nr_pages); |
| 147 | else |
| 148 | __count_vm_events(UNEVICTABLE_PGSTRANDED, nr_pages); |
| 149 | } |
| 150 | |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 151 | /* folio_evictable() has to be checked *after* clearing Mlocked */ |
| 152 | if (isolated && folio_test_unevictable(folio) && folio_evictable(folio)) { |
| 153 | lruvec_del_folio(lruvec, folio); |
| 154 | folio_clear_unevictable(folio); |
| 155 | lruvec_add_folio(lruvec, folio); |
Hugh Dickins | 07ca760 | 2022-02-14 18:29:54 -0800 | [diff] [blame] | 156 | __count_vm_events(UNEVICTABLE_PGRESCUED, nr_pages); |
| 157 | } |
| 158 | out: |
Hugh Dickins | 2fbb0c1 | 2022-02-14 18:37:29 -0800 | [diff] [blame] | 159 | if (isolated) |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 160 | folio_set_lru(folio); |
Hugh Dickins | 2fbb0c1 | 2022-02-14 18:37:29 -0800 | [diff] [blame] | 161 | return lruvec; |
| 162 | } |
| 163 | |
| 164 | /* |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 165 | * Flags held in the low bits of a struct folio pointer on the mlock_fbatch. |
Hugh Dickins | 2fbb0c1 | 2022-02-14 18:37:29 -0800 | [diff] [blame] | 166 | */ |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 167 | #define LRU_FOLIO 0x1 |
| 168 | #define NEW_FOLIO 0x2 |
| 169 | static inline struct folio *mlock_lru(struct folio *folio) |
Hugh Dickins | 2fbb0c1 | 2022-02-14 18:37:29 -0800 | [diff] [blame] | 170 | { |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 171 | return (struct folio *)((unsigned long)folio + LRU_FOLIO); |
Hugh Dickins | 2fbb0c1 | 2022-02-14 18:37:29 -0800 | [diff] [blame] | 172 | } |
| 173 | |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 174 | static inline struct folio *mlock_new(struct folio *folio) |
Hugh Dickins | 2fbb0c1 | 2022-02-14 18:37:29 -0800 | [diff] [blame] | 175 | { |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 176 | return (struct folio *)((unsigned long)folio + NEW_FOLIO); |
Hugh Dickins | 2fbb0c1 | 2022-02-14 18:37:29 -0800 | [diff] [blame] | 177 | } |
| 178 | |
| 179 | /* |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 180 | * mlock_folio_batch() is derived from folio_batch_move_lru(): perhaps that can |
| 181 | * make use of such folio pointer flags in future, but for now just keep it for |
| 182 | * mlock. We could use three separate folio batches instead, but one feels |
| 183 | * better (munlocking a full folio batch does not need to drain mlocking folio |
| 184 | * batches first). |
Hugh Dickins | 2fbb0c1 | 2022-02-14 18:37:29 -0800 | [diff] [blame] | 185 | */ |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 186 | static void mlock_folio_batch(struct folio_batch *fbatch) |
Hugh Dickins | 2fbb0c1 | 2022-02-14 18:37:29 -0800 | [diff] [blame] | 187 | { |
| 188 | struct lruvec *lruvec = NULL; |
| 189 | unsigned long mlock; |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 190 | struct folio *folio; |
Hugh Dickins | 2fbb0c1 | 2022-02-14 18:37:29 -0800 | [diff] [blame] | 191 | int i; |
| 192 | |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 193 | for (i = 0; i < folio_batch_count(fbatch); i++) { |
| 194 | folio = fbatch->folios[i]; |
| 195 | mlock = (unsigned long)folio & (LRU_FOLIO | NEW_FOLIO); |
| 196 | folio = (struct folio *)((unsigned long)folio - mlock); |
| 197 | fbatch->folios[i] = folio; |
Hugh Dickins | 2fbb0c1 | 2022-02-14 18:37:29 -0800 | [diff] [blame] | 198 | |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 199 | if (mlock & LRU_FOLIO) |
| 200 | lruvec = __mlock_folio(folio, lruvec); |
| 201 | else if (mlock & NEW_FOLIO) |
| 202 | lruvec = __mlock_new_folio(folio, lruvec); |
Hugh Dickins | 2fbb0c1 | 2022-02-14 18:37:29 -0800 | [diff] [blame] | 203 | else |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 204 | lruvec = __munlock_folio(folio, lruvec); |
Hugh Dickins | 2fbb0c1 | 2022-02-14 18:37:29 -0800 | [diff] [blame] | 205 | } |
| 206 | |
| 207 | if (lruvec) |
| 208 | unlock_page_lruvec_irq(lruvec); |
Matthew Wilcox (Oracle) | 99fbb6b | 2024-02-27 17:42:35 +0000 | [diff] [blame] | 209 | folios_put(fbatch); |
Hugh Dickins | 2fbb0c1 | 2022-02-14 18:37:29 -0800 | [diff] [blame] | 210 | } |
| 211 | |
Lorenzo Stoakes | 96f97c4 | 2023-01-12 12:39:31 +0000 | [diff] [blame] | 212 | void mlock_drain_local(void) |
Hugh Dickins | 2fbb0c1 | 2022-02-14 18:37:29 -0800 | [diff] [blame] | 213 | { |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 214 | struct folio_batch *fbatch; |
Hugh Dickins | 2fbb0c1 | 2022-02-14 18:37:29 -0800 | [diff] [blame] | 215 | |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 216 | local_lock(&mlock_fbatch.lock); |
| 217 | fbatch = this_cpu_ptr(&mlock_fbatch.fbatch); |
| 218 | if (folio_batch_count(fbatch)) |
| 219 | mlock_folio_batch(fbatch); |
| 220 | local_unlock(&mlock_fbatch.lock); |
Sebastian Andrzej Siewior | adb11e7 | 2022-04-01 11:28:33 -0700 | [diff] [blame] | 221 | } |
| 222 | |
Lorenzo Stoakes | 96f97c4 | 2023-01-12 12:39:31 +0000 | [diff] [blame] | 223 | void mlock_drain_remote(int cpu) |
Sebastian Andrzej Siewior | adb11e7 | 2022-04-01 11:28:33 -0700 | [diff] [blame] | 224 | { |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 225 | struct folio_batch *fbatch; |
Sebastian Andrzej Siewior | adb11e7 | 2022-04-01 11:28:33 -0700 | [diff] [blame] | 226 | |
| 227 | WARN_ON_ONCE(cpu_online(cpu)); |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 228 | fbatch = &per_cpu(mlock_fbatch.fbatch, cpu); |
| 229 | if (folio_batch_count(fbatch)) |
| 230 | mlock_folio_batch(fbatch); |
Hugh Dickins | 2fbb0c1 | 2022-02-14 18:37:29 -0800 | [diff] [blame] | 231 | } |
| 232 | |
Lorenzo Stoakes | 96f97c4 | 2023-01-12 12:39:31 +0000 | [diff] [blame] | 233 | bool need_mlock_drain(int cpu) |
Hugh Dickins | 2fbb0c1 | 2022-02-14 18:37:29 -0800 | [diff] [blame] | 234 | { |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 235 | return folio_batch_count(&per_cpu(mlock_fbatch.fbatch, cpu)); |
Lee Schermerhorn | 6927c1d | 2009-12-14 17:59:55 -0800 | [diff] [blame] | 236 | } |
Nick Piggin | b291f00 | 2008-10-18 20:26:44 -0700 | [diff] [blame] | 237 | |
Michel Lespinasse | ff6a6da | 2013-02-27 17:02:44 -0800 | [diff] [blame] | 238 | /** |
Matthew Wilcox (Oracle) | dcc5d33 | 2022-02-15 13:33:59 -0500 | [diff] [blame] | 239 | * mlock_folio - mlock a folio already on (or temporarily off) LRU |
| 240 | * @folio: folio to be mlocked. |
Hugh Dickins | 3d470fc | 2011-10-31 17:09:43 -0700 | [diff] [blame] | 241 | */ |
Matthew Wilcox (Oracle) | dcc5d33 | 2022-02-15 13:33:59 -0500 | [diff] [blame] | 242 | void mlock_folio(struct folio *folio) |
Hugh Dickins | 3d470fc | 2011-10-31 17:09:43 -0700 | [diff] [blame] | 243 | { |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 244 | struct folio_batch *fbatch; |
Sebastian Andrzej Siewior | adb11e7 | 2022-04-01 11:28:33 -0700 | [diff] [blame] | 245 | |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 246 | local_lock(&mlock_fbatch.lock); |
| 247 | fbatch = this_cpu_ptr(&mlock_fbatch.fbatch); |
Hugh Dickins | 3d470fc | 2011-10-31 17:09:43 -0700 | [diff] [blame] | 248 | |
Matthew Wilcox (Oracle) | dcc5d33 | 2022-02-15 13:33:59 -0500 | [diff] [blame] | 249 | if (!folio_test_set_mlocked(folio)) { |
| 250 | int nr_pages = folio_nr_pages(folio); |
Hugh Dickins | 3d470fc | 2011-10-31 17:09:43 -0700 | [diff] [blame] | 251 | |
Matthew Wilcox (Oracle) | dcc5d33 | 2022-02-15 13:33:59 -0500 | [diff] [blame] | 252 | zone_stat_mod_folio(folio, NR_MLOCK, nr_pages); |
Hugh Dickins | 2fbb0c1 | 2022-02-14 18:37:29 -0800 | [diff] [blame] | 253 | __count_vm_events(UNEVICTABLE_PGMLOCKED, nr_pages); |
Hugh Dickins | 53f79ac | 2009-12-14 17:58:58 -0800 | [diff] [blame] | 254 | } |
Nick Piggin | 5344b7e | 2008-10-18 20:26:51 -0700 | [diff] [blame] | 255 | |
Matthew Wilcox (Oracle) | dcc5d33 | 2022-02-15 13:33:59 -0500 | [diff] [blame] | 256 | folio_get(folio); |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 257 | if (!folio_batch_add(fbatch, mlock_lru(folio)) || |
Matthew Wilcox (Oracle) | dcc5d33 | 2022-02-15 13:33:59 -0500 | [diff] [blame] | 258 | folio_test_large(folio) || lru_cache_disabled()) |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 259 | mlock_folio_batch(fbatch); |
| 260 | local_unlock(&mlock_fbatch.lock); |
Nick Piggin | 5344b7e | 2008-10-18 20:26:51 -0700 | [diff] [blame] | 261 | } |
| 262 | |
Hugh Dickins | 2fbb0c1 | 2022-02-14 18:37:29 -0800 | [diff] [blame] | 263 | /** |
Lorenzo Stoakes | 96f97c4 | 2023-01-12 12:39:31 +0000 | [diff] [blame] | 264 | * mlock_new_folio - mlock a newly allocated folio not yet on LRU |
| 265 | * @folio: folio to be mlocked, either normal or a THP head. |
Lee Schermerhorn | 6927c1d | 2009-12-14 17:59:55 -0800 | [diff] [blame] | 266 | */ |
Lorenzo Stoakes | 96f97c4 | 2023-01-12 12:39:31 +0000 | [diff] [blame] | 267 | void mlock_new_folio(struct folio *folio) |
Lee Schermerhorn | 6927c1d | 2009-12-14 17:59:55 -0800 | [diff] [blame] | 268 | { |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 269 | struct folio_batch *fbatch; |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 270 | int nr_pages = folio_nr_pages(folio); |
Hugh Dickins | 2fbb0c1 | 2022-02-14 18:37:29 -0800 | [diff] [blame] | 271 | |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 272 | local_lock(&mlock_fbatch.lock); |
| 273 | fbatch = this_cpu_ptr(&mlock_fbatch.fbatch); |
| 274 | folio_set_mlocked(folio); |
| 275 | |
| 276 | zone_stat_mod_folio(folio, NR_MLOCK, nr_pages); |
Hugh Dickins | 2fbb0c1 | 2022-02-14 18:37:29 -0800 | [diff] [blame] | 277 | __count_vm_events(UNEVICTABLE_PGMLOCKED, nr_pages); |
| 278 | |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 279 | folio_get(folio); |
| 280 | if (!folio_batch_add(fbatch, mlock_new(folio)) || |
| 281 | folio_test_large(folio) || lru_cache_disabled()) |
| 282 | mlock_folio_batch(fbatch); |
| 283 | local_unlock(&mlock_fbatch.lock); |
Nick Piggin | 5344b7e | 2008-10-18 20:26:51 -0700 | [diff] [blame] | 284 | } |
| 285 | |
Hugh Dickins | 2fbb0c1 | 2022-02-14 18:37:29 -0800 | [diff] [blame] | 286 | /** |
Lorenzo Stoakes | 96f97c4 | 2023-01-12 12:39:31 +0000 | [diff] [blame] | 287 | * munlock_folio - munlock a folio |
| 288 | * @folio: folio to be munlocked, either normal or a THP head. |
Rik van Riel | ba470de | 2008-10-18 20:26:50 -0700 | [diff] [blame] | 289 | */ |
Lorenzo Stoakes | 96f97c4 | 2023-01-12 12:39:31 +0000 | [diff] [blame] | 290 | void munlock_folio(struct folio *folio) |
Hugh Dickins | 408e82b | 2009-09-21 17:03:23 -0700 | [diff] [blame] | 291 | { |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 292 | struct folio_batch *fbatch; |
Vlastimil Babka | 56afe477d | 2013-09-11 14:22:32 -0700 | [diff] [blame] | 293 | |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 294 | local_lock(&mlock_fbatch.lock); |
| 295 | fbatch = this_cpu_ptr(&mlock_fbatch.fbatch); |
Vlastimil Babka | 5b40998 | 2013-09-11 14:22:33 -0700 | [diff] [blame] | 296 | /* |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 297 | * folio_test_clear_mlocked(folio) must be left to __munlock_folio(), |
| 298 | * which will check whether the folio is multiply mlocked. |
Vlastimil Babka | 5b40998 | 2013-09-11 14:22:33 -0700 | [diff] [blame] | 299 | */ |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 300 | folio_get(folio); |
| 301 | if (!folio_batch_add(fbatch, folio) || |
| 302 | folio_test_large(folio) || lru_cache_disabled()) |
| 303 | mlock_folio_batch(fbatch); |
| 304 | local_unlock(&mlock_fbatch.lock); |
Vlastimil Babka | 7a8010c | 2013-09-11 14:22:35 -0700 | [diff] [blame] | 305 | } |
Vlastimil Babka | 56afe477d | 2013-09-11 14:22:32 -0700 | [diff] [blame] | 306 | |
Yin Fengwei | dc68bad | 2023-09-18 15:33:18 +0800 | [diff] [blame] | 307 | static inline unsigned int folio_mlock_step(struct folio *folio, |
| 308 | pte_t *pte, unsigned long addr, unsigned long end) |
| 309 | { |
Lance Yang | f742829 | 2024-06-11 09:04:18 +0800 | [diff] [blame] | 310 | const fpb_t fpb_flags = FPB_IGNORE_DIRTY | FPB_IGNORE_SOFT_DIRTY; |
| 311 | unsigned int count = (end - addr) >> PAGE_SHIFT; |
Yin Fengwei | dc68bad | 2023-09-18 15:33:18 +0800 | [diff] [blame] | 312 | pte_t ptent = ptep_get(pte); |
| 313 | |
| 314 | if (!folio_test_large(folio)) |
| 315 | return 1; |
| 316 | |
Lance Yang | f742829 | 2024-06-11 09:04:18 +0800 | [diff] [blame] | 317 | return folio_pte_batch(folio, addr, pte, ptent, count, fpb_flags, NULL, |
| 318 | NULL, NULL); |
Yin Fengwei | dc68bad | 2023-09-18 15:33:18 +0800 | [diff] [blame] | 319 | } |
| 320 | |
| 321 | static inline bool allow_mlock_munlock(struct folio *folio, |
| 322 | struct vm_area_struct *vma, unsigned long start, |
| 323 | unsigned long end, unsigned int step) |
| 324 | { |
| 325 | /* |
| 326 | * For unlock, allow munlock large folio which is partially |
| 327 | * mapped to VMA. As it's possible that large folio is |
| 328 | * mlocked and VMA is split later. |
| 329 | * |
| 330 | * During memory pressure, such kind of large folio can |
| 331 | * be split. And the pages are not in VM_LOCKed VMA |
| 332 | * can be reclaimed. |
| 333 | */ |
| 334 | if (!(vma->vm_flags & VM_LOCKED)) |
| 335 | return true; |
| 336 | |
Hugh Dickins | b1454b4 | 2023-10-23 23:38:41 -0700 | [diff] [blame] | 337 | /* folio_within_range() cannot take KSM, but any small folio is OK */ |
| 338 | if (!folio_test_large(folio)) |
| 339 | return true; |
| 340 | |
Yin Fengwei | dc68bad | 2023-09-18 15:33:18 +0800 | [diff] [blame] | 341 | /* folio not in range [start, end), skip mlock */ |
| 342 | if (!folio_within_range(folio, vma, start, end)) |
| 343 | return false; |
| 344 | |
| 345 | /* folio is not fully mapped, skip mlock */ |
| 346 | if (step != folio_nr_pages(folio)) |
| 347 | return false; |
| 348 | |
| 349 | return true; |
| 350 | } |
| 351 | |
Hugh Dickins | 34b6792 | 2022-02-14 18:31:48 -0800 | [diff] [blame] | 352 | static int mlock_pte_range(pmd_t *pmd, unsigned long addr, |
| 353 | unsigned long end, struct mm_walk *walk) |
Hugh Dickins | 408e82b | 2009-09-21 17:03:23 -0700 | [diff] [blame] | 354 | |
Hugh Dickins | 408e82b | 2009-09-21 17:03:23 -0700 | [diff] [blame] | 355 | { |
Hugh Dickins | 34b6792 | 2022-02-14 18:31:48 -0800 | [diff] [blame] | 356 | struct vm_area_struct *vma = walk->vma; |
Hugh Dickins | 6e91971 | 2009-09-21 17:03:32 -0700 | [diff] [blame] | 357 | spinlock_t *ptl; |
Hugh Dickins | 34b6792 | 2022-02-14 18:31:48 -0800 | [diff] [blame] | 358 | pte_t *start_pte, *pte; |
Ryan Roberts | c33c794 | 2023-06-12 16:15:45 +0100 | [diff] [blame] | 359 | pte_t ptent; |
Lorenzo Stoakes | 96f97c4 | 2023-01-12 12:39:31 +0000 | [diff] [blame] | 360 | struct folio *folio; |
Yin Fengwei | dc68bad | 2023-09-18 15:33:18 +0800 | [diff] [blame] | 361 | unsigned int step = 1; |
| 362 | unsigned long start = addr; |
Michel Lespinasse | ff6a6da | 2013-02-27 17:02:44 -0800 | [diff] [blame] | 363 | |
Hugh Dickins | 34b6792 | 2022-02-14 18:31:48 -0800 | [diff] [blame] | 364 | ptl = pmd_trans_huge_lock(pmd, vma); |
| 365 | if (ptl) { |
| 366 | if (!pmd_present(*pmd)) |
| 367 | goto out; |
| 368 | if (is_huge_zero_pmd(*pmd)) |
| 369 | goto out; |
Matthew Wilcox (Oracle) | e06d03d | 2024-03-26 20:28:23 +0000 | [diff] [blame] | 370 | folio = pmd_folio(*pmd); |
Hugh Dickins | 34b6792 | 2022-02-14 18:31:48 -0800 | [diff] [blame] | 371 | if (vma->vm_flags & VM_LOCKED) |
Lorenzo Stoakes | 96f97c4 | 2023-01-12 12:39:31 +0000 | [diff] [blame] | 372 | mlock_folio(folio); |
Hugh Dickins | 34b6792 | 2022-02-14 18:31:48 -0800 | [diff] [blame] | 373 | else |
Lorenzo Stoakes | 96f97c4 | 2023-01-12 12:39:31 +0000 | [diff] [blame] | 374 | munlock_folio(folio); |
Hugh Dickins | 34b6792 | 2022-02-14 18:31:48 -0800 | [diff] [blame] | 375 | goto out; |
Nick Piggin | b291f00 | 2008-10-18 20:26:44 -0700 | [diff] [blame] | 376 | } |
Hugh Dickins | 34b6792 | 2022-02-14 18:31:48 -0800 | [diff] [blame] | 377 | |
| 378 | start_pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); |
Hugh Dickins | 7780d04 | 2023-06-08 18:17:26 -0700 | [diff] [blame] | 379 | if (!start_pte) { |
| 380 | walk->action = ACTION_AGAIN; |
| 381 | return 0; |
| 382 | } |
Yin Fengwei | dc68bad | 2023-09-18 15:33:18 +0800 | [diff] [blame] | 383 | |
Hugh Dickins | 34b6792 | 2022-02-14 18:31:48 -0800 | [diff] [blame] | 384 | for (pte = start_pte; addr != end; pte++, addr += PAGE_SIZE) { |
Ryan Roberts | c33c794 | 2023-06-12 16:15:45 +0100 | [diff] [blame] | 385 | ptent = ptep_get(pte); |
| 386 | if (!pte_present(ptent)) |
Hugh Dickins | 34b6792 | 2022-02-14 18:31:48 -0800 | [diff] [blame] | 387 | continue; |
Ryan Roberts | c33c794 | 2023-06-12 16:15:45 +0100 | [diff] [blame] | 388 | folio = vm_normal_folio(vma, addr, ptent); |
Lorenzo Stoakes | 96f97c4 | 2023-01-12 12:39:31 +0000 | [diff] [blame] | 389 | if (!folio || folio_is_zone_device(folio)) |
Hugh Dickins | 34b6792 | 2022-02-14 18:31:48 -0800 | [diff] [blame] | 390 | continue; |
Yin Fengwei | dc68bad | 2023-09-18 15:33:18 +0800 | [diff] [blame] | 391 | |
| 392 | step = folio_mlock_step(folio, pte, addr, end); |
| 393 | if (!allow_mlock_munlock(folio, vma, start, end, step)) |
| 394 | goto next_entry; |
| 395 | |
Hugh Dickins | 34b6792 | 2022-02-14 18:31:48 -0800 | [diff] [blame] | 396 | if (vma->vm_flags & VM_LOCKED) |
Lorenzo Stoakes | 96f97c4 | 2023-01-12 12:39:31 +0000 | [diff] [blame] | 397 | mlock_folio(folio); |
Hugh Dickins | 34b6792 | 2022-02-14 18:31:48 -0800 | [diff] [blame] | 398 | else |
Lorenzo Stoakes | 96f97c4 | 2023-01-12 12:39:31 +0000 | [diff] [blame] | 399 | munlock_folio(folio); |
Yin Fengwei | dc68bad | 2023-09-18 15:33:18 +0800 | [diff] [blame] | 400 | |
| 401 | next_entry: |
| 402 | pte += step - 1; |
| 403 | addr += (step - 1) << PAGE_SHIFT; |
Hugh Dickins | 34b6792 | 2022-02-14 18:31:48 -0800 | [diff] [blame] | 404 | } |
| 405 | pte_unmap(start_pte); |
| 406 | out: |
| 407 | spin_unlock(ptl); |
| 408 | cond_resched(); |
| 409 | return 0; |
Nick Piggin | b291f00 | 2008-10-18 20:26:44 -0700 | [diff] [blame] | 410 | } |
| 411 | |
| 412 | /* |
Hugh Dickins | 34b6792 | 2022-02-14 18:31:48 -0800 | [diff] [blame] | 413 | * mlock_vma_pages_range() - mlock any pages already in the range, |
| 414 | * or munlock all pages in the range. |
| 415 | * @vma - vma containing range to be mlock()ed or munlock()ed |
Rik van Riel | ba470de | 2008-10-18 20:26:50 -0700 | [diff] [blame] | 416 | * @start - start address in @vma of the range |
Hugh Dickins | 34b6792 | 2022-02-14 18:31:48 -0800 | [diff] [blame] | 417 | * @end - end of range in @vma |
| 418 | * @newflags - the new set of flags for @vma. |
Rik van Riel | ba470de | 2008-10-18 20:26:50 -0700 | [diff] [blame] | 419 | * |
Hugh Dickins | 34b6792 | 2022-02-14 18:31:48 -0800 | [diff] [blame] | 420 | * Called for mlock(), mlock2() and mlockall(), to set @vma VM_LOCKED; |
| 421 | * called for munlock() and munlockall(), to clear VM_LOCKED from @vma. |
Nick Piggin | b291f00 | 2008-10-18 20:26:44 -0700 | [diff] [blame] | 422 | */ |
Hugh Dickins | 34b6792 | 2022-02-14 18:31:48 -0800 | [diff] [blame] | 423 | static void mlock_vma_pages_range(struct vm_area_struct *vma, |
| 424 | unsigned long start, unsigned long end, vm_flags_t newflags) |
Nick Piggin | b291f00 | 2008-10-18 20:26:44 -0700 | [diff] [blame] | 425 | { |
Hugh Dickins | 34b6792 | 2022-02-14 18:31:48 -0800 | [diff] [blame] | 426 | static const struct mm_walk_ops mlock_walk_ops = { |
| 427 | .pmd_entry = mlock_pte_range, |
Suren Baghdasaryan | 49b0638 | 2023-08-04 08:27:19 -0700 | [diff] [blame] | 428 | .walk_lock = PGWALK_WRLOCK_VERIFY, |
Hugh Dickins | 34b6792 | 2022-02-14 18:31:48 -0800 | [diff] [blame] | 429 | }; |
Hugh Dickins | 408e82b | 2009-09-21 17:03:23 -0700 | [diff] [blame] | 430 | |
Hugh Dickins | 34b6792 | 2022-02-14 18:31:48 -0800 | [diff] [blame] | 431 | /* |
| 432 | * There is a slight chance that concurrent page migration, |
| 433 | * or page reclaim finding a page of this now-VM_LOCKED vma, |
Matthew Wilcox (Oracle) | 7efecff | 2023-01-16 19:28:25 +0000 | [diff] [blame] | 434 | * will call mlock_vma_folio() and raise page's mlock_count: |
Hugh Dickins | 34b6792 | 2022-02-14 18:31:48 -0800 | [diff] [blame] | 435 | * double counting, leaving the page unevictable indefinitely. |
Matthew Wilcox (Oracle) | 7efecff | 2023-01-16 19:28:25 +0000 | [diff] [blame] | 436 | * Communicate this danger to mlock_vma_folio() with VM_IO, |
Hugh Dickins | 34b6792 | 2022-02-14 18:31:48 -0800 | [diff] [blame] | 437 | * which is a VM_SPECIAL flag not allowed on VM_LOCKED vmas. |
| 438 | * mmap_lock is held in write mode here, so this weird |
| 439 | * combination should not be visible to other mmap_lock users; |
| 440 | * but WRITE_ONCE so rmap walkers must see VM_IO if VM_LOCKED. |
| 441 | */ |
| 442 | if (newflags & VM_LOCKED) |
| 443 | newflags |= VM_IO; |
Suren Baghdasaryan | 60081bf | 2023-08-04 08:27:22 -0700 | [diff] [blame] | 444 | vma_start_write(vma); |
Suren Baghdasaryan | 601c3c2 | 2023-01-31 16:01:16 -0800 | [diff] [blame] | 445 | vm_flags_reset_once(vma, newflags); |
Michel Lespinasse | ff6a6da | 2013-02-27 17:02:44 -0800 | [diff] [blame] | 446 | |
Hugh Dickins | 34b6792 | 2022-02-14 18:31:48 -0800 | [diff] [blame] | 447 | lru_add_drain(); |
| 448 | walk_page_range(vma->vm_mm, start, end, &mlock_walk_ops, NULL); |
| 449 | lru_add_drain(); |
Vlastimil Babka | 7a8010c | 2013-09-11 14:22:35 -0700 | [diff] [blame] | 450 | |
Hugh Dickins | 34b6792 | 2022-02-14 18:31:48 -0800 | [diff] [blame] | 451 | if (newflags & VM_IO) { |
| 452 | newflags &= ~VM_IO; |
Suren Baghdasaryan | 601c3c2 | 2023-01-31 16:01:16 -0800 | [diff] [blame] | 453 | vm_flags_reset_once(vma, newflags); |
Hugh Dickins | 408e82b | 2009-09-21 17:03:23 -0700 | [diff] [blame] | 454 | } |
Nick Piggin | b291f00 | 2008-10-18 20:26:44 -0700 | [diff] [blame] | 455 | } |
| 456 | |
| 457 | /* |
| 458 | * mlock_fixup - handle mlock[all]/munlock[all] requests. |
| 459 | * |
| 460 | * Filters out "special" vmas -- VM_LOCKED never gets set for these, and |
| 461 | * munlock is a no-op. However, for some special vmas, we go ahead and |
Michel Lespinasse | cea10a1 | 2013-02-22 16:32:44 -0800 | [diff] [blame] | 462 | * populate the ptes. |
Nick Piggin | b291f00 | 2008-10-18 20:26:44 -0700 | [diff] [blame] | 463 | * |
| 464 | * For vmas that pass the filters, merge/split as appropriate. |
| 465 | */ |
Liam R. Howlett | 37598f5 | 2023-01-20 11:26:19 -0500 | [diff] [blame] | 466 | static int mlock_fixup(struct vma_iterator *vmi, struct vm_area_struct *vma, |
| 467 | struct vm_area_struct **prev, unsigned long start, |
| 468 | unsigned long end, vm_flags_t newflags) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 469 | { |
Nick Piggin | b291f00 | 2008-10-18 20:26:44 -0700 | [diff] [blame] | 470 | struct mm_struct *mm = vma->vm_mm; |
Nick Piggin | b291f00 | 2008-10-18 20:26:44 -0700 | [diff] [blame] | 471 | int nr_pages; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 472 | int ret = 0; |
Hugh Dickins | 34b6792 | 2022-02-14 18:31:48 -0800 | [diff] [blame] | 473 | vm_flags_t oldflags = vma->vm_flags; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 474 | |
Hugh Dickins | 34b6792 | 2022-02-14 18:31:48 -0800 | [diff] [blame] | 475 | if (newflags == oldflags || (oldflags & VM_SPECIAL) || |
Dave Jiang | e1fb4a0 | 2018-08-17 15:43:40 -0700 | [diff] [blame] | 476 | is_vm_hugetlb_page(vma) || vma == get_gate_vma(current->mm) || |
Jason A. Donenfeld | 9651fce | 2022-12-08 17:55:04 +0100 | [diff] [blame] | 477 | vma_is_dax(vma) || vma_is_secretmem(vma) || (oldflags & VM_DROPPABLE)) |
Eric B Munson | b0f205c | 2015-11-05 18:51:39 -0800 | [diff] [blame] | 478 | /* don't set VM_LOCKED or VM_LOCKONFAULT and don't count */ |
| 479 | goto out; |
Nick Piggin | b291f00 | 2008-10-18 20:26:44 -0700 | [diff] [blame] | 480 | |
Lorenzo Stoakes | 94d7d92 | 2023-10-11 18:04:28 +0100 | [diff] [blame] | 481 | vma = vma_modify_flags(vmi, *prev, vma, start, end, newflags); |
| 482 | if (IS_ERR(vma)) { |
| 483 | ret = PTR_ERR(vma); |
| 484 | goto out; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 485 | } |
| 486 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 487 | /* |
Nick Piggin | b291f00 | 2008-10-18 20:26:44 -0700 | [diff] [blame] | 488 | * Keep track of amount of locked VM. |
| 489 | */ |
| 490 | nr_pages = (end - start) >> PAGE_SHIFT; |
Hugh Dickins | 34b6792 | 2022-02-14 18:31:48 -0800 | [diff] [blame] | 491 | if (!(newflags & VM_LOCKED)) |
Nick Piggin | b291f00 | 2008-10-18 20:26:44 -0700 | [diff] [blame] | 492 | nr_pages = -nr_pages; |
Hugh Dickins | 34b6792 | 2022-02-14 18:31:48 -0800 | [diff] [blame] | 493 | else if (oldflags & VM_LOCKED) |
Simon Guo | b155b4f | 2016-10-07 16:59:40 -0700 | [diff] [blame] | 494 | nr_pages = 0; |
Nick Piggin | b291f00 | 2008-10-18 20:26:44 -0700 | [diff] [blame] | 495 | mm->locked_vm += nr_pages; |
| 496 | |
| 497 | /* |
Michel Lespinasse | c1e8d7c | 2020-06-08 21:33:54 -0700 | [diff] [blame] | 498 | * vm_flags is protected by the mmap_lock held in write mode. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 499 | * It's okay if try_to_unmap_one unmaps a page just after we |
Kirill A. Shutemov | fc05f56 | 2015-04-14 15:44:39 -0700 | [diff] [blame] | 500 | * set VM_LOCKED, populate_vma_page_range will bring it back. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 501 | */ |
Hugh Dickins | 34b6792 | 2022-02-14 18:31:48 -0800 | [diff] [blame] | 502 | if ((newflags & VM_LOCKED) && (oldflags & VM_LOCKED)) { |
| 503 | /* No work to do, and mlocking twice would be wrong */ |
Suren Baghdasaryan | 60081bf | 2023-08-04 08:27:22 -0700 | [diff] [blame] | 504 | vma_start_write(vma); |
Suren Baghdasaryan | 1c71222 | 2023-01-26 11:37:49 -0800 | [diff] [blame] | 505 | vm_flags_reset(vma, newflags); |
Hugh Dickins | 34b6792 | 2022-02-14 18:31:48 -0800 | [diff] [blame] | 506 | } else { |
| 507 | mlock_vma_pages_range(vma, start, end, newflags); |
| 508 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 509 | out: |
Nick Piggin | b291f00 | 2008-10-18 20:26:44 -0700 | [diff] [blame] | 510 | *prev = vma; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 511 | return ret; |
| 512 | } |
| 513 | |
Eric B Munson | 1aab92ec | 2015-11-05 18:51:29 -0800 | [diff] [blame] | 514 | static int apply_vma_lock_flags(unsigned long start, size_t len, |
| 515 | vm_flags_t flags) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 516 | { |
| 517 | unsigned long nstart, end, tmp; |
Zhiyuan Dai | 68d68ff | 2021-05-04 18:40:12 -0700 | [diff] [blame] | 518 | struct vm_area_struct *vma, *prev; |
Liam R. Howlett | 37598f5 | 2023-01-20 11:26:19 -0500 | [diff] [blame] | 519 | VMA_ITERATOR(vmi, current->mm, start); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 520 | |
Alexander Kuleshov | 8fd9e48 | 2015-11-05 18:46:49 -0800 | [diff] [blame] | 521 | VM_BUG_ON(offset_in_page(start)); |
Michel Lespinasse | fed067d | 2011-01-13 15:46:10 -0800 | [diff] [blame] | 522 | VM_BUG_ON(len != PAGE_ALIGN(len)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 523 | end = start + len; |
| 524 | if (end < start) |
| 525 | return -EINVAL; |
| 526 | if (end == start) |
| 527 | return 0; |
Liam R. Howlett | 37598f5 | 2023-01-20 11:26:19 -0500 | [diff] [blame] | 528 | vma = vma_iter_load(&vmi); |
Matthew Wilcox (Oracle) | 33108b0 | 2022-09-06 19:49:02 +0000 | [diff] [blame] | 529 | if (!vma) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 530 | return -ENOMEM; |
| 531 | |
Liam R. Howlett | 37598f5 | 2023-01-20 11:26:19 -0500 | [diff] [blame] | 532 | prev = vma_prev(&vmi); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 533 | if (start > vma->vm_start) |
| 534 | prev = vma; |
| 535 | |
Liam R. Howlett | 37598f5 | 2023-01-20 11:26:19 -0500 | [diff] [blame] | 536 | nstart = start; |
| 537 | tmp = vma->vm_start; |
| 538 | for_each_vma_range(vmi, vma, end) { |
Liam R. Howlett | 2658f94d6 | 2023-07-11 13:50:20 -0400 | [diff] [blame] | 539 | int error; |
Liam R. Howlett | 37598f5 | 2023-01-20 11:26:19 -0500 | [diff] [blame] | 540 | vm_flags_t newflags; |
Eric B Munson | 1aab92ec | 2015-11-05 18:51:29 -0800 | [diff] [blame] | 541 | |
Liam R. Howlett | 37598f5 | 2023-01-20 11:26:19 -0500 | [diff] [blame] | 542 | if (vma->vm_start != tmp) |
| 543 | return -ENOMEM; |
| 544 | |
Suren Baghdasaryan | e430a95 | 2023-01-26 11:37:48 -0800 | [diff] [blame] | 545 | newflags = vma->vm_flags & ~VM_LOCKED_MASK; |
Eric B Munson | 1aab92ec | 2015-11-05 18:51:29 -0800 | [diff] [blame] | 546 | newflags |= flags; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 547 | /* Here we know that vma->vm_start <= nstart < vma->vm_end. */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 548 | tmp = vma->vm_end; |
| 549 | if (tmp > end) |
| 550 | tmp = end; |
Liam R. Howlett | 37598f5 | 2023-01-20 11:26:19 -0500 | [diff] [blame] | 551 | error = mlock_fixup(&vmi, vma, &prev, nstart, tmp, newflags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 552 | if (error) |
Liam R. Howlett | 2658f94d6 | 2023-07-11 13:50:20 -0400 | [diff] [blame] | 553 | return error; |
| 554 | tmp = vma_iter_end(&vmi); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 555 | nstart = tmp; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 556 | } |
Liam R. Howlett | 37598f5 | 2023-01-20 11:26:19 -0500 | [diff] [blame] | 557 | |
Liam R. Howlett | 2658f94d6 | 2023-07-11 13:50:20 -0400 | [diff] [blame] | 558 | if (tmp < end) |
Liam R. Howlett | 37598f5 | 2023-01-20 11:26:19 -0500 | [diff] [blame] | 559 | return -ENOMEM; |
| 560 | |
Liam R. Howlett | 2658f94d6 | 2023-07-11 13:50:20 -0400 | [diff] [blame] | 561 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 562 | } |
| 563 | |
Simon Guo | 0cf2f6f | 2016-10-07 16:59:36 -0700 | [diff] [blame] | 564 | /* |
| 565 | * Go through vma areas and sum size of mlocked |
| 566 | * vma pages, as return value. |
| 567 | * Note deferred memory locking case(mlock2(,,MLOCK_ONFAULT) |
| 568 | * is also counted. |
| 569 | * Return value: previously mlocked page counts |
| 570 | */ |
swkhack | 0874bb4 | 2019-06-13 15:56:08 -0700 | [diff] [blame] | 571 | static unsigned long count_mm_mlocked_page_nr(struct mm_struct *mm, |
Simon Guo | 0cf2f6f | 2016-10-07 16:59:36 -0700 | [diff] [blame] | 572 | unsigned long start, size_t len) |
| 573 | { |
| 574 | struct vm_area_struct *vma; |
swkhack | 0874bb4 | 2019-06-13 15:56:08 -0700 | [diff] [blame] | 575 | unsigned long count = 0; |
Matthew Wilcox (Oracle) | 33108b0 | 2022-09-06 19:49:02 +0000 | [diff] [blame] | 576 | unsigned long end; |
| 577 | VMA_ITERATOR(vmi, mm, start); |
Simon Guo | 0cf2f6f | 2016-10-07 16:59:36 -0700 | [diff] [blame] | 578 | |
Matthew Wilcox (Oracle) | 33108b0 | 2022-09-06 19:49:02 +0000 | [diff] [blame] | 579 | /* Don't overflow past ULONG_MAX */ |
| 580 | if (unlikely(ULONG_MAX - len < start)) |
| 581 | end = ULONG_MAX; |
| 582 | else |
| 583 | end = start + len; |
Liam Howlett | 6607189 | 2022-06-15 17:40:58 +0000 | [diff] [blame] | 584 | |
Matthew Wilcox (Oracle) | 33108b0 | 2022-09-06 19:49:02 +0000 | [diff] [blame] | 585 | for_each_vma_range(vmi, vma, end) { |
Simon Guo | 0cf2f6f | 2016-10-07 16:59:36 -0700 | [diff] [blame] | 586 | if (vma->vm_flags & VM_LOCKED) { |
| 587 | if (start > vma->vm_start) |
| 588 | count -= (start - vma->vm_start); |
Matthew Wilcox (Oracle) | 33108b0 | 2022-09-06 19:49:02 +0000 | [diff] [blame] | 589 | if (end < vma->vm_end) { |
| 590 | count += end - vma->vm_start; |
Simon Guo | 0cf2f6f | 2016-10-07 16:59:36 -0700 | [diff] [blame] | 591 | break; |
| 592 | } |
| 593 | count += vma->vm_end - vma->vm_start; |
| 594 | } |
| 595 | } |
| 596 | |
| 597 | return count >> PAGE_SHIFT; |
| 598 | } |
| 599 | |
Hugh Dickins | ebcbc6e | 2022-02-14 18:20:24 -0800 | [diff] [blame] | 600 | /* |
| 601 | * convert get_user_pages() return value to posix mlock() error |
| 602 | */ |
| 603 | static int __mlock_posix_error_return(long retval) |
| 604 | { |
| 605 | if (retval == -EFAULT) |
| 606 | retval = -ENOMEM; |
| 607 | else if (retval == -ENOMEM) |
| 608 | retval = -EAGAIN; |
| 609 | return retval; |
| 610 | } |
| 611 | |
Michal Hocko | dc0ef0d | 2016-05-23 16:25:27 -0700 | [diff] [blame] | 612 | static __must_check int do_mlock(unsigned long start, size_t len, vm_flags_t flags) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 613 | { |
| 614 | unsigned long locked; |
| 615 | unsigned long lock_limit; |
| 616 | int error = -ENOMEM; |
| 617 | |
Andrey Konovalov | 057d3389 | 2019-09-25 16:48:30 -0700 | [diff] [blame] | 618 | start = untagged_addr(start); |
| 619 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 620 | if (!can_do_mlock()) |
| 621 | return -EPERM; |
| 622 | |
Alexander Kuleshov | 8fd9e48 | 2015-11-05 18:46:49 -0800 | [diff] [blame] | 623 | len = PAGE_ALIGN(len + (offset_in_page(start))); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 624 | start &= PAGE_MASK; |
| 625 | |
Jiri Slaby | 59e99e5 | 2010-03-05 13:41:44 -0800 | [diff] [blame] | 626 | lock_limit = rlimit(RLIMIT_MEMLOCK); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 627 | lock_limit >>= PAGE_SHIFT; |
Davidlohr Bueso | 1f1cd70 | 2014-01-21 15:49:16 -0800 | [diff] [blame] | 628 | locked = len >> PAGE_SHIFT; |
| 629 | |
Michel Lespinasse | d8ed45c | 2020-06-08 21:33:25 -0700 | [diff] [blame] | 630 | if (mmap_write_lock_killable(current->mm)) |
Michal Hocko | dc0ef0d | 2016-05-23 16:25:27 -0700 | [diff] [blame] | 631 | return -EINTR; |
Davidlohr Bueso | 1f1cd70 | 2014-01-21 15:49:16 -0800 | [diff] [blame] | 632 | |
| 633 | locked += current->mm->locked_vm; |
Simon Guo | 0cf2f6f | 2016-10-07 16:59:36 -0700 | [diff] [blame] | 634 | if ((locked > lock_limit) && (!capable(CAP_IPC_LOCK))) { |
| 635 | /* |
| 636 | * It is possible that the regions requested intersect with |
| 637 | * previously mlocked areas, that part area in "mm->locked_vm" |
| 638 | * should not be counted to new mlock increment count. So check |
| 639 | * and adjust locked count if necessary. |
| 640 | */ |
| 641 | locked -= count_mm_mlocked_page_nr(current->mm, |
| 642 | start, len); |
| 643 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 644 | |
| 645 | /* check against resource limits */ |
| 646 | if ((locked <= lock_limit) || capable(CAP_IPC_LOCK)) |
Eric B Munson | 1aab92ec | 2015-11-05 18:51:29 -0800 | [diff] [blame] | 647 | error = apply_vma_lock_flags(start, len, flags); |
Davidlohr Bueso | 1f1cd70 | 2014-01-21 15:49:16 -0800 | [diff] [blame] | 648 | |
Michel Lespinasse | d8ed45c | 2020-06-08 21:33:25 -0700 | [diff] [blame] | 649 | mmap_write_unlock(current->mm); |
Kirill A. Shutemov | c561259 | 2015-04-14 15:44:42 -0700 | [diff] [blame] | 650 | if (error) |
| 651 | return error; |
| 652 | |
| 653 | error = __mm_populate(start, len, 0); |
| 654 | if (error) |
| 655 | return __mlock_posix_error_return(error); |
| 656 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 657 | } |
| 658 | |
Eric B Munson | 1aab92ec | 2015-11-05 18:51:29 -0800 | [diff] [blame] | 659 | SYSCALL_DEFINE2(mlock, unsigned long, start, size_t, len) |
| 660 | { |
| 661 | return do_mlock(start, len, VM_LOCKED); |
| 662 | } |
| 663 | |
Eric B Munson | a8ca5d0 | 2015-11-05 18:51:33 -0800 | [diff] [blame] | 664 | SYSCALL_DEFINE3(mlock2, unsigned long, start, size_t, len, int, flags) |
| 665 | { |
Eric B Munson | b0f205c | 2015-11-05 18:51:39 -0800 | [diff] [blame] | 666 | vm_flags_t vm_flags = VM_LOCKED; |
| 667 | |
| 668 | if (flags & ~MLOCK_ONFAULT) |
Eric B Munson | a8ca5d0 | 2015-11-05 18:51:33 -0800 | [diff] [blame] | 669 | return -EINVAL; |
| 670 | |
Eric B Munson | b0f205c | 2015-11-05 18:51:39 -0800 | [diff] [blame] | 671 | if (flags & MLOCK_ONFAULT) |
| 672 | vm_flags |= VM_LOCKONFAULT; |
| 673 | |
| 674 | return do_mlock(start, len, vm_flags); |
Eric B Munson | a8ca5d0 | 2015-11-05 18:51:33 -0800 | [diff] [blame] | 675 | } |
| 676 | |
Heiko Carstens | 6a6160a | 2009-01-14 14:14:15 +0100 | [diff] [blame] | 677 | SYSCALL_DEFINE2(munlock, unsigned long, start, size_t, len) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 678 | { |
| 679 | int ret; |
| 680 | |
Andrey Konovalov | 057d3389 | 2019-09-25 16:48:30 -0700 | [diff] [blame] | 681 | start = untagged_addr(start); |
| 682 | |
Alexander Kuleshov | 8fd9e48 | 2015-11-05 18:46:49 -0800 | [diff] [blame] | 683 | len = PAGE_ALIGN(len + (offset_in_page(start))); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 684 | start &= PAGE_MASK; |
Davidlohr Bueso | 1f1cd70 | 2014-01-21 15:49:16 -0800 | [diff] [blame] | 685 | |
Michel Lespinasse | d8ed45c | 2020-06-08 21:33:25 -0700 | [diff] [blame] | 686 | if (mmap_write_lock_killable(current->mm)) |
Michal Hocko | dc0ef0d | 2016-05-23 16:25:27 -0700 | [diff] [blame] | 687 | return -EINTR; |
Eric B Munson | 1aab92ec | 2015-11-05 18:51:29 -0800 | [diff] [blame] | 688 | ret = apply_vma_lock_flags(start, len, 0); |
Michel Lespinasse | d8ed45c | 2020-06-08 21:33:25 -0700 | [diff] [blame] | 689 | mmap_write_unlock(current->mm); |
Davidlohr Bueso | 1f1cd70 | 2014-01-21 15:49:16 -0800 | [diff] [blame] | 690 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 691 | return ret; |
| 692 | } |
| 693 | |
Eric B Munson | b0f205c | 2015-11-05 18:51:39 -0800 | [diff] [blame] | 694 | /* |
| 695 | * Take the MCL_* flags passed into mlockall (or 0 if called from munlockall) |
| 696 | * and translate into the appropriate modifications to mm->def_flags and/or the |
| 697 | * flags for all current VMAs. |
| 698 | * |
| 699 | * There are a couple of subtleties with this. If mlockall() is called multiple |
| 700 | * times with different flags, the values do not necessarily stack. If mlockall |
| 701 | * is called once including the MCL_FUTURE flag and then a second time without |
| 702 | * it, VM_LOCKED and VM_LOCKONFAULT will be cleared from mm->def_flags. |
| 703 | */ |
Eric B Munson | 1aab92ec | 2015-11-05 18:51:29 -0800 | [diff] [blame] | 704 | static int apply_mlockall_flags(int flags) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 705 | { |
Liam R. Howlett | 37598f5 | 2023-01-20 11:26:19 -0500 | [diff] [blame] | 706 | VMA_ITERATOR(vmi, current->mm, 0); |
Zhiyuan Dai | 68d68ff | 2021-05-04 18:40:12 -0700 | [diff] [blame] | 707 | struct vm_area_struct *vma, *prev = NULL; |
Eric B Munson | b0f205c | 2015-11-05 18:51:39 -0800 | [diff] [blame] | 708 | vm_flags_t to_add = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 709 | |
Suren Baghdasaryan | e430a95 | 2023-01-26 11:37:48 -0800 | [diff] [blame] | 710 | current->mm->def_flags &= ~VM_LOCKED_MASK; |
Eric B Munson | b0f205c | 2015-11-05 18:51:39 -0800 | [diff] [blame] | 711 | if (flags & MCL_FUTURE) { |
Michel Lespinasse | 09a9f1d | 2013-03-28 16:26:23 -0700 | [diff] [blame] | 712 | current->mm->def_flags |= VM_LOCKED; |
Eric B Munson | 1aab92ec | 2015-11-05 18:51:29 -0800 | [diff] [blame] | 713 | |
Eric B Munson | b0f205c | 2015-11-05 18:51:39 -0800 | [diff] [blame] | 714 | if (flags & MCL_ONFAULT) |
| 715 | current->mm->def_flags |= VM_LOCKONFAULT; |
| 716 | |
| 717 | if (!(flags & MCL_CURRENT)) |
| 718 | goto out; |
| 719 | } |
| 720 | |
| 721 | if (flags & MCL_CURRENT) { |
| 722 | to_add |= VM_LOCKED; |
| 723 | if (flags & MCL_ONFAULT) |
| 724 | to_add |= VM_LOCKONFAULT; |
| 725 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 726 | |
Liam R. Howlett | 37598f5 | 2023-01-20 11:26:19 -0500 | [diff] [blame] | 727 | for_each_vma(vmi, vma) { |
KOSAKI Motohiro | ca16d14 | 2011-05-26 19:16:19 +0900 | [diff] [blame] | 728 | vm_flags_t newflags; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 729 | |
Suren Baghdasaryan | e430a95 | 2023-01-26 11:37:48 -0800 | [diff] [blame] | 730 | newflags = vma->vm_flags & ~VM_LOCKED_MASK; |
Eric B Munson | b0f205c | 2015-11-05 18:51:39 -0800 | [diff] [blame] | 731 | newflags |= to_add; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 732 | |
| 733 | /* Ignore errors */ |
Liam R. Howlett | 37598f5 | 2023-01-20 11:26:19 -0500 | [diff] [blame] | 734 | mlock_fixup(&vmi, vma, &prev, vma->vm_start, vma->vm_end, |
| 735 | newflags); |
Paul E. McKenney | 50d4fb7 | 2017-10-24 08:22:18 -0700 | [diff] [blame] | 736 | cond_resched(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 737 | } |
| 738 | out: |
| 739 | return 0; |
| 740 | } |
| 741 | |
Heiko Carstens | 3480b25 | 2009-01-14 14:14:16 +0100 | [diff] [blame] | 742 | SYSCALL_DEFINE1(mlockall, int, flags) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 743 | { |
| 744 | unsigned long lock_limit; |
Alexey Klimov | 86d2adcc | 2015-11-05 18:46:00 -0800 | [diff] [blame] | 745 | int ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 746 | |
Potyra, Stefan | dedca63 | 2019-06-13 15:55:55 -0700 | [diff] [blame] | 747 | if (!flags || (flags & ~(MCL_CURRENT | MCL_FUTURE | MCL_ONFAULT)) || |
| 748 | flags == MCL_ONFAULT) |
Alexey Klimov | 86d2adcc | 2015-11-05 18:46:00 -0800 | [diff] [blame] | 749 | return -EINVAL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 750 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 751 | if (!can_do_mlock()) |
Alexey Klimov | 86d2adcc | 2015-11-05 18:46:00 -0800 | [diff] [blame] | 752 | return -EPERM; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 753 | |
Jiri Slaby | 59e99e5 | 2010-03-05 13:41:44 -0800 | [diff] [blame] | 754 | lock_limit = rlimit(RLIMIT_MEMLOCK); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 755 | lock_limit >>= PAGE_SHIFT; |
| 756 | |
Michel Lespinasse | d8ed45c | 2020-06-08 21:33:25 -0700 | [diff] [blame] | 757 | if (mmap_write_lock_killable(current->mm)) |
Michal Hocko | dc0ef0d | 2016-05-23 16:25:27 -0700 | [diff] [blame] | 758 | return -EINTR; |
Davidlohr Bueso | 1f1cd70 | 2014-01-21 15:49:16 -0800 | [diff] [blame] | 759 | |
Michal Hocko | dc0ef0d | 2016-05-23 16:25:27 -0700 | [diff] [blame] | 760 | ret = -ENOMEM; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 761 | if (!(flags & MCL_CURRENT) || (current->mm->total_vm <= lock_limit) || |
| 762 | capable(CAP_IPC_LOCK)) |
Eric B Munson | 1aab92ec | 2015-11-05 18:51:29 -0800 | [diff] [blame] | 763 | ret = apply_mlockall_flags(flags); |
Michel Lespinasse | d8ed45c | 2020-06-08 21:33:25 -0700 | [diff] [blame] | 764 | mmap_write_unlock(current->mm); |
Michel Lespinasse | bebeb3d | 2013-02-22 16:32:37 -0800 | [diff] [blame] | 765 | if (!ret && (flags & MCL_CURRENT)) |
| 766 | mm_populate(0, TASK_SIZE); |
Alexey Klimov | 86d2adcc | 2015-11-05 18:46:00 -0800 | [diff] [blame] | 767 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 768 | return ret; |
| 769 | } |
| 770 | |
Heiko Carstens | 3480b25 | 2009-01-14 14:14:16 +0100 | [diff] [blame] | 771 | SYSCALL_DEFINE0(munlockall) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 772 | { |
| 773 | int ret; |
| 774 | |
Michel Lespinasse | d8ed45c | 2020-06-08 21:33:25 -0700 | [diff] [blame] | 775 | if (mmap_write_lock_killable(current->mm)) |
Michal Hocko | dc0ef0d | 2016-05-23 16:25:27 -0700 | [diff] [blame] | 776 | return -EINTR; |
Eric B Munson | 1aab92ec | 2015-11-05 18:51:29 -0800 | [diff] [blame] | 777 | ret = apply_mlockall_flags(0); |
Michel Lespinasse | d8ed45c | 2020-06-08 21:33:25 -0700 | [diff] [blame] | 778 | mmap_write_unlock(current->mm); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 779 | return ret; |
| 780 | } |
| 781 | |
| 782 | /* |
| 783 | * Objects with different lifetime than processes (SHM_LOCK and SHM_HUGETLB |
| 784 | * shm segments) get accounted against the user_struct instead. |
| 785 | */ |
| 786 | static DEFINE_SPINLOCK(shmlock_user_lock); |
| 787 | |
Alexey Gladkov | d7c9e99 | 2021-04-22 14:27:14 +0200 | [diff] [blame] | 788 | int user_shm_lock(size_t size, struct ucounts *ucounts) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 789 | { |
| 790 | unsigned long lock_limit, locked; |
Alexey Gladkov | d7c9e99 | 2021-04-22 14:27:14 +0200 | [diff] [blame] | 791 | long memlock; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 792 | int allowed = 0; |
| 793 | |
| 794 | locked = (size + PAGE_SIZE - 1) >> PAGE_SHIFT; |
Jiri Slaby | 59e99e5 | 2010-03-05 13:41:44 -0800 | [diff] [blame] | 795 | lock_limit = rlimit(RLIMIT_MEMLOCK); |
Miaohe Lin | e97824f | 2022-03-22 16:09:18 +0800 | [diff] [blame] | 796 | if (lock_limit != RLIM_INFINITY) |
| 797 | lock_limit >>= PAGE_SHIFT; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 798 | spin_lock(&shmlock_user_lock); |
Alexey Gladkov | d7c9e99 | 2021-04-22 14:27:14 +0200 | [diff] [blame] | 799 | memlock = inc_rlimit_ucounts(ucounts, UCOUNT_RLIMIT_MEMLOCK, locked); |
| 800 | |
Miaohe Lin | e97824f | 2022-03-22 16:09:18 +0800 | [diff] [blame] | 801 | if ((memlock == LONG_MAX || memlock > lock_limit) && !capable(CAP_IPC_LOCK)) { |
Alexey Gladkov | d7c9e99 | 2021-04-22 14:27:14 +0200 | [diff] [blame] | 802 | dec_rlimit_ucounts(ucounts, UCOUNT_RLIMIT_MEMLOCK, locked); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 803 | goto out; |
Alexey Gladkov | d7c9e99 | 2021-04-22 14:27:14 +0200 | [diff] [blame] | 804 | } |
| 805 | if (!get_ucounts(ucounts)) { |
| 806 | dec_rlimit_ucounts(ucounts, UCOUNT_RLIMIT_MEMLOCK, locked); |
Miaohe Lin | 5c2a956 | 2022-03-22 14:44:56 -0700 | [diff] [blame] | 807 | allowed = 0; |
Alexey Gladkov | d7c9e99 | 2021-04-22 14:27:14 +0200 | [diff] [blame] | 808 | goto out; |
| 809 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 810 | allowed = 1; |
| 811 | out: |
| 812 | spin_unlock(&shmlock_user_lock); |
| 813 | return allowed; |
| 814 | } |
| 815 | |
Alexey Gladkov | d7c9e99 | 2021-04-22 14:27:14 +0200 | [diff] [blame] | 816 | void user_shm_unlock(size_t size, struct ucounts *ucounts) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 817 | { |
| 818 | spin_lock(&shmlock_user_lock); |
Alexey Gladkov | d7c9e99 | 2021-04-22 14:27:14 +0200 | [diff] [blame] | 819 | dec_rlimit_ucounts(ucounts, UCOUNT_RLIMIT_MEMLOCK, (size + PAGE_SIZE - 1) >> PAGE_SHIFT); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 820 | spin_unlock(&shmlock_user_lock); |
Alexey Gladkov | d7c9e99 | 2021-04-22 14:27:14 +0200 | [diff] [blame] | 821 | put_ucounts(ucounts); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 822 | } |