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); |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 209 | release_pages(fbatch->folios, fbatch->nr); |
| 210 | folio_batch_reinit(fbatch); |
Hugh Dickins | 2fbb0c1 | 2022-02-14 18:37:29 -0800 | [diff] [blame] | 211 | } |
| 212 | |
Lorenzo Stoakes | 96f97c4 | 2023-01-12 12:39:31 +0000 | [diff] [blame] | 213 | void mlock_drain_local(void) |
Hugh Dickins | 2fbb0c1 | 2022-02-14 18:37:29 -0800 | [diff] [blame] | 214 | { |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 215 | struct folio_batch *fbatch; |
Hugh Dickins | 2fbb0c1 | 2022-02-14 18:37:29 -0800 | [diff] [blame] | 216 | |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 217 | local_lock(&mlock_fbatch.lock); |
| 218 | fbatch = this_cpu_ptr(&mlock_fbatch.fbatch); |
| 219 | if (folio_batch_count(fbatch)) |
| 220 | mlock_folio_batch(fbatch); |
| 221 | local_unlock(&mlock_fbatch.lock); |
Sebastian Andrzej Siewior | adb11e7 | 2022-04-01 11:28:33 -0700 | [diff] [blame] | 222 | } |
| 223 | |
Lorenzo Stoakes | 96f97c4 | 2023-01-12 12:39:31 +0000 | [diff] [blame] | 224 | void mlock_drain_remote(int cpu) |
Sebastian Andrzej Siewior | adb11e7 | 2022-04-01 11:28:33 -0700 | [diff] [blame] | 225 | { |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 226 | struct folio_batch *fbatch; |
Sebastian Andrzej Siewior | adb11e7 | 2022-04-01 11:28:33 -0700 | [diff] [blame] | 227 | |
| 228 | WARN_ON_ONCE(cpu_online(cpu)); |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 229 | fbatch = &per_cpu(mlock_fbatch.fbatch, cpu); |
| 230 | if (folio_batch_count(fbatch)) |
| 231 | mlock_folio_batch(fbatch); |
Hugh Dickins | 2fbb0c1 | 2022-02-14 18:37:29 -0800 | [diff] [blame] | 232 | } |
| 233 | |
Lorenzo Stoakes | 96f97c4 | 2023-01-12 12:39:31 +0000 | [diff] [blame] | 234 | bool need_mlock_drain(int cpu) |
Hugh Dickins | 2fbb0c1 | 2022-02-14 18:37:29 -0800 | [diff] [blame] | 235 | { |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 236 | return folio_batch_count(&per_cpu(mlock_fbatch.fbatch, cpu)); |
Lee Schermerhorn | 6927c1d | 2009-12-14 17:59:55 -0800 | [diff] [blame] | 237 | } |
Nick Piggin | b291f00 | 2008-10-18 20:26:44 -0700 | [diff] [blame] | 238 | |
Michel Lespinasse | ff6a6da | 2013-02-27 17:02:44 -0800 | [diff] [blame] | 239 | /** |
Matthew Wilcox (Oracle) | dcc5d33 | 2022-02-15 13:33:59 -0500 | [diff] [blame] | 240 | * mlock_folio - mlock a folio already on (or temporarily off) LRU |
| 241 | * @folio: folio to be mlocked. |
Hugh Dickins | 3d470fc | 2011-10-31 17:09:43 -0700 | [diff] [blame] | 242 | */ |
Matthew Wilcox (Oracle) | dcc5d33 | 2022-02-15 13:33:59 -0500 | [diff] [blame] | 243 | void mlock_folio(struct folio *folio) |
Hugh Dickins | 3d470fc | 2011-10-31 17:09:43 -0700 | [diff] [blame] | 244 | { |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 245 | struct folio_batch *fbatch; |
Sebastian Andrzej Siewior | adb11e7 | 2022-04-01 11:28:33 -0700 | [diff] [blame] | 246 | |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 247 | local_lock(&mlock_fbatch.lock); |
| 248 | fbatch = this_cpu_ptr(&mlock_fbatch.fbatch); |
Hugh Dickins | 3d470fc | 2011-10-31 17:09:43 -0700 | [diff] [blame] | 249 | |
Matthew Wilcox (Oracle) | dcc5d33 | 2022-02-15 13:33:59 -0500 | [diff] [blame] | 250 | if (!folio_test_set_mlocked(folio)) { |
| 251 | int nr_pages = folio_nr_pages(folio); |
Hugh Dickins | 3d470fc | 2011-10-31 17:09:43 -0700 | [diff] [blame] | 252 | |
Matthew Wilcox (Oracle) | dcc5d33 | 2022-02-15 13:33:59 -0500 | [diff] [blame] | 253 | zone_stat_mod_folio(folio, NR_MLOCK, nr_pages); |
Hugh Dickins | 2fbb0c1 | 2022-02-14 18:37:29 -0800 | [diff] [blame] | 254 | __count_vm_events(UNEVICTABLE_PGMLOCKED, nr_pages); |
Hugh Dickins | 53f79ac | 2009-12-14 17:58:58 -0800 | [diff] [blame] | 255 | } |
Nick Piggin | 5344b7e | 2008-10-18 20:26:51 -0700 | [diff] [blame] | 256 | |
Matthew Wilcox (Oracle) | dcc5d33 | 2022-02-15 13:33:59 -0500 | [diff] [blame] | 257 | folio_get(folio); |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 258 | if (!folio_batch_add(fbatch, mlock_lru(folio)) || |
Matthew Wilcox (Oracle) | dcc5d33 | 2022-02-15 13:33:59 -0500 | [diff] [blame] | 259 | folio_test_large(folio) || lru_cache_disabled()) |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 260 | mlock_folio_batch(fbatch); |
| 261 | local_unlock(&mlock_fbatch.lock); |
Nick Piggin | 5344b7e | 2008-10-18 20:26:51 -0700 | [diff] [blame] | 262 | } |
| 263 | |
Hugh Dickins | 2fbb0c1 | 2022-02-14 18:37:29 -0800 | [diff] [blame] | 264 | /** |
Lorenzo Stoakes | 96f97c4 | 2023-01-12 12:39:31 +0000 | [diff] [blame] | 265 | * mlock_new_folio - mlock a newly allocated folio not yet on LRU |
| 266 | * @folio: folio to be mlocked, either normal or a THP head. |
Lee Schermerhorn | 6927c1d | 2009-12-14 17:59:55 -0800 | [diff] [blame] | 267 | */ |
Lorenzo Stoakes | 96f97c4 | 2023-01-12 12:39:31 +0000 | [diff] [blame] | 268 | void mlock_new_folio(struct folio *folio) |
Lee Schermerhorn | 6927c1d | 2009-12-14 17:59:55 -0800 | [diff] [blame] | 269 | { |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 270 | struct folio_batch *fbatch; |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 271 | int nr_pages = folio_nr_pages(folio); |
Hugh Dickins | 2fbb0c1 | 2022-02-14 18:37:29 -0800 | [diff] [blame] | 272 | |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 273 | local_lock(&mlock_fbatch.lock); |
| 274 | fbatch = this_cpu_ptr(&mlock_fbatch.fbatch); |
| 275 | folio_set_mlocked(folio); |
| 276 | |
| 277 | zone_stat_mod_folio(folio, NR_MLOCK, nr_pages); |
Hugh Dickins | 2fbb0c1 | 2022-02-14 18:37:29 -0800 | [diff] [blame] | 278 | __count_vm_events(UNEVICTABLE_PGMLOCKED, nr_pages); |
| 279 | |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 280 | folio_get(folio); |
| 281 | if (!folio_batch_add(fbatch, mlock_new(folio)) || |
| 282 | folio_test_large(folio) || lru_cache_disabled()) |
| 283 | mlock_folio_batch(fbatch); |
| 284 | local_unlock(&mlock_fbatch.lock); |
Nick Piggin | 5344b7e | 2008-10-18 20:26:51 -0700 | [diff] [blame] | 285 | } |
| 286 | |
Hugh Dickins | 2fbb0c1 | 2022-02-14 18:37:29 -0800 | [diff] [blame] | 287 | /** |
Lorenzo Stoakes | 96f97c4 | 2023-01-12 12:39:31 +0000 | [diff] [blame] | 288 | * munlock_folio - munlock a folio |
| 289 | * @folio: folio to be munlocked, either normal or a THP head. |
Rik van Riel | ba470de | 2008-10-18 20:26:50 -0700 | [diff] [blame] | 290 | */ |
Lorenzo Stoakes | 96f97c4 | 2023-01-12 12:39:31 +0000 | [diff] [blame] | 291 | void munlock_folio(struct folio *folio) |
Hugh Dickins | 408e82b | 2009-09-21 17:03:23 -0700 | [diff] [blame] | 292 | { |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 293 | struct folio_batch *fbatch; |
Vlastimil Babka | 56afe477d | 2013-09-11 14:22:32 -0700 | [diff] [blame] | 294 | |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 295 | local_lock(&mlock_fbatch.lock); |
| 296 | fbatch = this_cpu_ptr(&mlock_fbatch.fbatch); |
Vlastimil Babka | 5b40998 | 2013-09-11 14:22:33 -0700 | [diff] [blame] | 297 | /* |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 298 | * folio_test_clear_mlocked(folio) must be left to __munlock_folio(), |
| 299 | * which will check whether the folio is multiply mlocked. |
Vlastimil Babka | 5b40998 | 2013-09-11 14:22:33 -0700 | [diff] [blame] | 300 | */ |
Lorenzo Stoakes | 90d0721 | 2023-01-12 12:39:29 +0000 | [diff] [blame] | 301 | folio_get(folio); |
| 302 | if (!folio_batch_add(fbatch, folio) || |
| 303 | folio_test_large(folio) || lru_cache_disabled()) |
| 304 | mlock_folio_batch(fbatch); |
| 305 | local_unlock(&mlock_fbatch.lock); |
Vlastimil Babka | 7a8010c | 2013-09-11 14:22:35 -0700 | [diff] [blame] | 306 | } |
Vlastimil Babka | 56afe477d | 2013-09-11 14:22:32 -0700 | [diff] [blame] | 307 | |
Hugh Dickins | 34b6792 | 2022-02-14 18:31:48 -0800 | [diff] [blame] | 308 | static int mlock_pte_range(pmd_t *pmd, unsigned long addr, |
| 309 | unsigned long end, struct mm_walk *walk) |
Hugh Dickins | 408e82b | 2009-09-21 17:03:23 -0700 | [diff] [blame] | 310 | |
Hugh Dickins | 408e82b | 2009-09-21 17:03:23 -0700 | [diff] [blame] | 311 | { |
Hugh Dickins | 34b6792 | 2022-02-14 18:31:48 -0800 | [diff] [blame] | 312 | struct vm_area_struct *vma = walk->vma; |
Hugh Dickins | 6e91971 | 2009-09-21 17:03:32 -0700 | [diff] [blame] | 313 | spinlock_t *ptl; |
Hugh Dickins | 34b6792 | 2022-02-14 18:31:48 -0800 | [diff] [blame] | 314 | pte_t *start_pte, *pte; |
Lorenzo Stoakes | 96f97c4 | 2023-01-12 12:39:31 +0000 | [diff] [blame] | 315 | struct folio *folio; |
Michel Lespinasse | ff6a6da | 2013-02-27 17:02:44 -0800 | [diff] [blame] | 316 | |
Hugh Dickins | 34b6792 | 2022-02-14 18:31:48 -0800 | [diff] [blame] | 317 | ptl = pmd_trans_huge_lock(pmd, vma); |
| 318 | if (ptl) { |
| 319 | if (!pmd_present(*pmd)) |
| 320 | goto out; |
| 321 | if (is_huge_zero_pmd(*pmd)) |
| 322 | goto out; |
Lorenzo Stoakes | 96f97c4 | 2023-01-12 12:39:31 +0000 | [diff] [blame] | 323 | folio = page_folio(pmd_page(*pmd)); |
Hugh Dickins | 34b6792 | 2022-02-14 18:31:48 -0800 | [diff] [blame] | 324 | if (vma->vm_flags & VM_LOCKED) |
Lorenzo Stoakes | 96f97c4 | 2023-01-12 12:39:31 +0000 | [diff] [blame] | 325 | mlock_folio(folio); |
Hugh Dickins | 34b6792 | 2022-02-14 18:31:48 -0800 | [diff] [blame] | 326 | else |
Lorenzo Stoakes | 96f97c4 | 2023-01-12 12:39:31 +0000 | [diff] [blame] | 327 | munlock_folio(folio); |
Hugh Dickins | 34b6792 | 2022-02-14 18:31:48 -0800 | [diff] [blame] | 328 | goto out; |
Nick Piggin | b291f00 | 2008-10-18 20:26:44 -0700 | [diff] [blame] | 329 | } |
Hugh Dickins | 34b6792 | 2022-02-14 18:31:48 -0800 | [diff] [blame] | 330 | |
| 331 | start_pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); |
| 332 | for (pte = start_pte; addr != end; pte++, addr += PAGE_SIZE) { |
| 333 | if (!pte_present(*pte)) |
| 334 | continue; |
Lorenzo Stoakes | 96f97c4 | 2023-01-12 12:39:31 +0000 | [diff] [blame] | 335 | folio = vm_normal_folio(vma, addr, *pte); |
| 336 | if (!folio || folio_is_zone_device(folio)) |
Hugh Dickins | 34b6792 | 2022-02-14 18:31:48 -0800 | [diff] [blame] | 337 | continue; |
Lorenzo Stoakes | 96f97c4 | 2023-01-12 12:39:31 +0000 | [diff] [blame] | 338 | if (folio_test_large(folio)) |
Hugh Dickins | 34b6792 | 2022-02-14 18:31:48 -0800 | [diff] [blame] | 339 | continue; |
| 340 | if (vma->vm_flags & VM_LOCKED) |
Lorenzo Stoakes | 96f97c4 | 2023-01-12 12:39:31 +0000 | [diff] [blame] | 341 | mlock_folio(folio); |
Hugh Dickins | 34b6792 | 2022-02-14 18:31:48 -0800 | [diff] [blame] | 342 | else |
Lorenzo Stoakes | 96f97c4 | 2023-01-12 12:39:31 +0000 | [diff] [blame] | 343 | munlock_folio(folio); |
Hugh Dickins | 34b6792 | 2022-02-14 18:31:48 -0800 | [diff] [blame] | 344 | } |
| 345 | pte_unmap(start_pte); |
| 346 | out: |
| 347 | spin_unlock(ptl); |
| 348 | cond_resched(); |
| 349 | return 0; |
Nick Piggin | b291f00 | 2008-10-18 20:26:44 -0700 | [diff] [blame] | 350 | } |
| 351 | |
| 352 | /* |
Hugh Dickins | 34b6792 | 2022-02-14 18:31:48 -0800 | [diff] [blame] | 353 | * mlock_vma_pages_range() - mlock any pages already in the range, |
| 354 | * or munlock all pages in the range. |
| 355 | * @vma - vma containing range to be mlock()ed or munlock()ed |
Rik van Riel | ba470de | 2008-10-18 20:26:50 -0700 | [diff] [blame] | 356 | * @start - start address in @vma of the range |
Hugh Dickins | 34b6792 | 2022-02-14 18:31:48 -0800 | [diff] [blame] | 357 | * @end - end of range in @vma |
| 358 | * @newflags - the new set of flags for @vma. |
Rik van Riel | ba470de | 2008-10-18 20:26:50 -0700 | [diff] [blame] | 359 | * |
Hugh Dickins | 34b6792 | 2022-02-14 18:31:48 -0800 | [diff] [blame] | 360 | * Called for mlock(), mlock2() and mlockall(), to set @vma VM_LOCKED; |
| 361 | * called for munlock() and munlockall(), to clear VM_LOCKED from @vma. |
Nick Piggin | b291f00 | 2008-10-18 20:26:44 -0700 | [diff] [blame] | 362 | */ |
Hugh Dickins | 34b6792 | 2022-02-14 18:31:48 -0800 | [diff] [blame] | 363 | static void mlock_vma_pages_range(struct vm_area_struct *vma, |
| 364 | unsigned long start, unsigned long end, vm_flags_t newflags) |
Nick Piggin | b291f00 | 2008-10-18 20:26:44 -0700 | [diff] [blame] | 365 | { |
Hugh Dickins | 34b6792 | 2022-02-14 18:31:48 -0800 | [diff] [blame] | 366 | static const struct mm_walk_ops mlock_walk_ops = { |
| 367 | .pmd_entry = mlock_pte_range, |
| 368 | }; |
Hugh Dickins | 408e82b | 2009-09-21 17:03:23 -0700 | [diff] [blame] | 369 | |
Hugh Dickins | 34b6792 | 2022-02-14 18:31:48 -0800 | [diff] [blame] | 370 | /* |
| 371 | * There is a slight chance that concurrent page migration, |
| 372 | * 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] | 373 | * will call mlock_vma_folio() and raise page's mlock_count: |
Hugh Dickins | 34b6792 | 2022-02-14 18:31:48 -0800 | [diff] [blame] | 374 | * double counting, leaving the page unevictable indefinitely. |
Matthew Wilcox (Oracle) | 7efecff | 2023-01-16 19:28:25 +0000 | [diff] [blame] | 375 | * Communicate this danger to mlock_vma_folio() with VM_IO, |
Hugh Dickins | 34b6792 | 2022-02-14 18:31:48 -0800 | [diff] [blame] | 376 | * which is a VM_SPECIAL flag not allowed on VM_LOCKED vmas. |
| 377 | * mmap_lock is held in write mode here, so this weird |
| 378 | * combination should not be visible to other mmap_lock users; |
| 379 | * but WRITE_ONCE so rmap walkers must see VM_IO if VM_LOCKED. |
| 380 | */ |
| 381 | if (newflags & VM_LOCKED) |
| 382 | newflags |= VM_IO; |
Suren Baghdasaryan | 601c3c2 | 2023-01-31 16:01:16 -0800 | [diff] [blame] | 383 | vm_flags_reset_once(vma, newflags); |
Michel Lespinasse | ff6a6da | 2013-02-27 17:02:44 -0800 | [diff] [blame] | 384 | |
Hugh Dickins | 34b6792 | 2022-02-14 18:31:48 -0800 | [diff] [blame] | 385 | lru_add_drain(); |
| 386 | walk_page_range(vma->vm_mm, start, end, &mlock_walk_ops, NULL); |
| 387 | lru_add_drain(); |
Vlastimil Babka | 7a8010c | 2013-09-11 14:22:35 -0700 | [diff] [blame] | 388 | |
Hugh Dickins | 34b6792 | 2022-02-14 18:31:48 -0800 | [diff] [blame] | 389 | if (newflags & VM_IO) { |
| 390 | newflags &= ~VM_IO; |
Suren Baghdasaryan | 601c3c2 | 2023-01-31 16:01:16 -0800 | [diff] [blame] | 391 | vm_flags_reset_once(vma, newflags); |
Hugh Dickins | 408e82b | 2009-09-21 17:03:23 -0700 | [diff] [blame] | 392 | } |
Nick Piggin | b291f00 | 2008-10-18 20:26:44 -0700 | [diff] [blame] | 393 | } |
| 394 | |
| 395 | /* |
| 396 | * mlock_fixup - handle mlock[all]/munlock[all] requests. |
| 397 | * |
| 398 | * Filters out "special" vmas -- VM_LOCKED never gets set for these, and |
| 399 | * 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] | 400 | * populate the ptes. |
Nick Piggin | b291f00 | 2008-10-18 20:26:44 -0700 | [diff] [blame] | 401 | * |
| 402 | * For vmas that pass the filters, merge/split as appropriate. |
| 403 | */ |
Liam R. Howlett | 37598f5 | 2023-01-20 11:26:19 -0500 | [diff] [blame] | 404 | static int mlock_fixup(struct vma_iterator *vmi, struct vm_area_struct *vma, |
| 405 | struct vm_area_struct **prev, unsigned long start, |
| 406 | unsigned long end, vm_flags_t newflags) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 407 | { |
Nick Piggin | b291f00 | 2008-10-18 20:26:44 -0700 | [diff] [blame] | 408 | struct mm_struct *mm = vma->vm_mm; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 409 | pgoff_t pgoff; |
Nick Piggin | b291f00 | 2008-10-18 20:26:44 -0700 | [diff] [blame] | 410 | int nr_pages; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 411 | int ret = 0; |
Hugh Dickins | 34b6792 | 2022-02-14 18:31:48 -0800 | [diff] [blame] | 412 | vm_flags_t oldflags = vma->vm_flags; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 413 | |
Hugh Dickins | 34b6792 | 2022-02-14 18:31:48 -0800 | [diff] [blame] | 414 | if (newflags == oldflags || (oldflags & VM_SPECIAL) || |
Dave Jiang | e1fb4a0 | 2018-08-17 15:43:40 -0700 | [diff] [blame] | 415 | is_vm_hugetlb_page(vma) || vma == get_gate_vma(current->mm) || |
Mike Rapoport | 1507f51 | 2021-07-07 18:08:03 -0700 | [diff] [blame] | 416 | vma_is_dax(vma) || vma_is_secretmem(vma)) |
Eric B Munson | b0f205c | 2015-11-05 18:51:39 -0800 | [diff] [blame] | 417 | /* don't set VM_LOCKED or VM_LOCKONFAULT and don't count */ |
| 418 | goto out; |
Nick Piggin | b291f00 | 2008-10-18 20:26:44 -0700 | [diff] [blame] | 419 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 420 | pgoff = vma->vm_pgoff + ((start - vma->vm_start) >> PAGE_SHIFT); |
Liam R. Howlett | 9760ebf | 2023-01-20 11:26:30 -0500 | [diff] [blame] | 421 | *prev = vma_merge(vmi, mm, *prev, start, end, newflags, |
Liam R. Howlett | 37598f5 | 2023-01-20 11:26:19 -0500 | [diff] [blame] | 422 | vma->anon_vma, vma->vm_file, pgoff, vma_policy(vma), |
| 423 | vma->vm_userfaultfd_ctx, anon_vma_name(vma)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 424 | if (*prev) { |
| 425 | vma = *prev; |
| 426 | goto success; |
| 427 | } |
| 428 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 429 | if (start != vma->vm_start) { |
Liam R. Howlett | 9760ebf | 2023-01-20 11:26:30 -0500 | [diff] [blame] | 430 | ret = split_vma(vmi, vma, start, 1); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 431 | if (ret) |
| 432 | goto out; |
| 433 | } |
| 434 | |
| 435 | if (end != vma->vm_end) { |
Liam R. Howlett | 9760ebf | 2023-01-20 11:26:30 -0500 | [diff] [blame] | 436 | ret = split_vma(vmi, vma, end, 0); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 437 | if (ret) |
| 438 | goto out; |
| 439 | } |
| 440 | |
| 441 | success: |
| 442 | /* |
Nick Piggin | b291f00 | 2008-10-18 20:26:44 -0700 | [diff] [blame] | 443 | * Keep track of amount of locked VM. |
| 444 | */ |
| 445 | nr_pages = (end - start) >> PAGE_SHIFT; |
Hugh Dickins | 34b6792 | 2022-02-14 18:31:48 -0800 | [diff] [blame] | 446 | if (!(newflags & VM_LOCKED)) |
Nick Piggin | b291f00 | 2008-10-18 20:26:44 -0700 | [diff] [blame] | 447 | nr_pages = -nr_pages; |
Hugh Dickins | 34b6792 | 2022-02-14 18:31:48 -0800 | [diff] [blame] | 448 | else if (oldflags & VM_LOCKED) |
Simon Guo | b155b4f | 2016-10-07 16:59:40 -0700 | [diff] [blame] | 449 | nr_pages = 0; |
Nick Piggin | b291f00 | 2008-10-18 20:26:44 -0700 | [diff] [blame] | 450 | mm->locked_vm += nr_pages; |
| 451 | |
| 452 | /* |
Michel Lespinasse | c1e8d7c | 2020-06-08 21:33:54 -0700 | [diff] [blame] | 453 | * vm_flags is protected by the mmap_lock held in write mode. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 454 | * 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] | 455 | * set VM_LOCKED, populate_vma_page_range will bring it back. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 456 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 457 | |
Hugh Dickins | 34b6792 | 2022-02-14 18:31:48 -0800 | [diff] [blame] | 458 | if ((newflags & VM_LOCKED) && (oldflags & VM_LOCKED)) { |
| 459 | /* No work to do, and mlocking twice would be wrong */ |
Suren Baghdasaryan | 1c71222 | 2023-01-26 11:37:49 -0800 | [diff] [blame] | 460 | vm_flags_reset(vma, newflags); |
Hugh Dickins | 34b6792 | 2022-02-14 18:31:48 -0800 | [diff] [blame] | 461 | } else { |
| 462 | mlock_vma_pages_range(vma, start, end, newflags); |
| 463 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 464 | out: |
Nick Piggin | b291f00 | 2008-10-18 20:26:44 -0700 | [diff] [blame] | 465 | *prev = vma; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 466 | return ret; |
| 467 | } |
| 468 | |
Eric B Munson | 1aab92ec | 2015-11-05 18:51:29 -0800 | [diff] [blame] | 469 | static int apply_vma_lock_flags(unsigned long start, size_t len, |
| 470 | vm_flags_t flags) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 471 | { |
| 472 | unsigned long nstart, end, tmp; |
Zhiyuan Dai | 68d68ff | 2021-05-04 18:40:12 -0700 | [diff] [blame] | 473 | struct vm_area_struct *vma, *prev; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 474 | int error; |
Liam R. Howlett | 37598f5 | 2023-01-20 11:26:19 -0500 | [diff] [blame] | 475 | VMA_ITERATOR(vmi, current->mm, start); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 476 | |
Alexander Kuleshov | 8fd9e48 | 2015-11-05 18:46:49 -0800 | [diff] [blame] | 477 | VM_BUG_ON(offset_in_page(start)); |
Michel Lespinasse | fed067d | 2011-01-13 15:46:10 -0800 | [diff] [blame] | 478 | VM_BUG_ON(len != PAGE_ALIGN(len)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 479 | end = start + len; |
| 480 | if (end < start) |
| 481 | return -EINVAL; |
| 482 | if (end == start) |
| 483 | return 0; |
Liam R. Howlett | 37598f5 | 2023-01-20 11:26:19 -0500 | [diff] [blame] | 484 | vma = vma_iter_load(&vmi); |
Matthew Wilcox (Oracle) | 33108b0 | 2022-09-06 19:49:02 +0000 | [diff] [blame] | 485 | if (!vma) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 486 | return -ENOMEM; |
| 487 | |
Liam R. Howlett | 37598f5 | 2023-01-20 11:26:19 -0500 | [diff] [blame] | 488 | prev = vma_prev(&vmi); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 489 | if (start > vma->vm_start) |
| 490 | prev = vma; |
| 491 | |
Liam R. Howlett | 37598f5 | 2023-01-20 11:26:19 -0500 | [diff] [blame] | 492 | nstart = start; |
| 493 | tmp = vma->vm_start; |
| 494 | for_each_vma_range(vmi, vma, end) { |
| 495 | vm_flags_t newflags; |
Eric B Munson | 1aab92ec | 2015-11-05 18:51:29 -0800 | [diff] [blame] | 496 | |
Liam R. Howlett | 37598f5 | 2023-01-20 11:26:19 -0500 | [diff] [blame] | 497 | if (vma->vm_start != tmp) |
| 498 | return -ENOMEM; |
| 499 | |
Suren Baghdasaryan | e430a95 | 2023-01-26 11:37:48 -0800 | [diff] [blame] | 500 | newflags = vma->vm_flags & ~VM_LOCKED_MASK; |
Eric B Munson | 1aab92ec | 2015-11-05 18:51:29 -0800 | [diff] [blame] | 501 | newflags |= flags; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 502 | /* Here we know that vma->vm_start <= nstart < vma->vm_end. */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 503 | tmp = vma->vm_end; |
| 504 | if (tmp > end) |
| 505 | tmp = end; |
Liam R. Howlett | 37598f5 | 2023-01-20 11:26:19 -0500 | [diff] [blame] | 506 | error = mlock_fixup(&vmi, vma, &prev, nstart, tmp, newflags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 507 | if (error) |
| 508 | break; |
| 509 | nstart = tmp; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 510 | } |
Liam R. Howlett | 37598f5 | 2023-01-20 11:26:19 -0500 | [diff] [blame] | 511 | |
| 512 | if (vma_iter_end(&vmi) < end) |
| 513 | return -ENOMEM; |
| 514 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 515 | return error; |
| 516 | } |
| 517 | |
Simon Guo | 0cf2f6f | 2016-10-07 16:59:36 -0700 | [diff] [blame] | 518 | /* |
| 519 | * Go through vma areas and sum size of mlocked |
| 520 | * vma pages, as return value. |
| 521 | * Note deferred memory locking case(mlock2(,,MLOCK_ONFAULT) |
| 522 | * is also counted. |
| 523 | * Return value: previously mlocked page counts |
| 524 | */ |
swkhack | 0874bb4 | 2019-06-13 15:56:08 -0700 | [diff] [blame] | 525 | static unsigned long count_mm_mlocked_page_nr(struct mm_struct *mm, |
Simon Guo | 0cf2f6f | 2016-10-07 16:59:36 -0700 | [diff] [blame] | 526 | unsigned long start, size_t len) |
| 527 | { |
| 528 | struct vm_area_struct *vma; |
swkhack | 0874bb4 | 2019-06-13 15:56:08 -0700 | [diff] [blame] | 529 | unsigned long count = 0; |
Matthew Wilcox (Oracle) | 33108b0 | 2022-09-06 19:49:02 +0000 | [diff] [blame] | 530 | unsigned long end; |
| 531 | VMA_ITERATOR(vmi, mm, start); |
Simon Guo | 0cf2f6f | 2016-10-07 16:59:36 -0700 | [diff] [blame] | 532 | |
Matthew Wilcox (Oracle) | 33108b0 | 2022-09-06 19:49:02 +0000 | [diff] [blame] | 533 | /* Don't overflow past ULONG_MAX */ |
| 534 | if (unlikely(ULONG_MAX - len < start)) |
| 535 | end = ULONG_MAX; |
| 536 | else |
| 537 | end = start + len; |
Liam Howlett | 6607189 | 2022-06-15 17:40:58 +0000 | [diff] [blame] | 538 | |
Matthew Wilcox (Oracle) | 33108b0 | 2022-09-06 19:49:02 +0000 | [diff] [blame] | 539 | for_each_vma_range(vmi, vma, end) { |
Simon Guo | 0cf2f6f | 2016-10-07 16:59:36 -0700 | [diff] [blame] | 540 | if (vma->vm_flags & VM_LOCKED) { |
| 541 | if (start > vma->vm_start) |
| 542 | count -= (start - vma->vm_start); |
Matthew Wilcox (Oracle) | 33108b0 | 2022-09-06 19:49:02 +0000 | [diff] [blame] | 543 | if (end < vma->vm_end) { |
| 544 | count += end - vma->vm_start; |
Simon Guo | 0cf2f6f | 2016-10-07 16:59:36 -0700 | [diff] [blame] | 545 | break; |
| 546 | } |
| 547 | count += vma->vm_end - vma->vm_start; |
| 548 | } |
| 549 | } |
| 550 | |
| 551 | return count >> PAGE_SHIFT; |
| 552 | } |
| 553 | |
Hugh Dickins | ebcbc6e | 2022-02-14 18:20:24 -0800 | [diff] [blame] | 554 | /* |
| 555 | * convert get_user_pages() return value to posix mlock() error |
| 556 | */ |
| 557 | static int __mlock_posix_error_return(long retval) |
| 558 | { |
| 559 | if (retval == -EFAULT) |
| 560 | retval = -ENOMEM; |
| 561 | else if (retval == -ENOMEM) |
| 562 | retval = -EAGAIN; |
| 563 | return retval; |
| 564 | } |
| 565 | |
Michal Hocko | dc0ef0d | 2016-05-23 16:25:27 -0700 | [diff] [blame] | 566 | 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] | 567 | { |
| 568 | unsigned long locked; |
| 569 | unsigned long lock_limit; |
| 570 | int error = -ENOMEM; |
| 571 | |
Andrey Konovalov | 057d3389 | 2019-09-25 16:48:30 -0700 | [diff] [blame] | 572 | start = untagged_addr(start); |
| 573 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 574 | if (!can_do_mlock()) |
| 575 | return -EPERM; |
| 576 | |
Alexander Kuleshov | 8fd9e48 | 2015-11-05 18:46:49 -0800 | [diff] [blame] | 577 | len = PAGE_ALIGN(len + (offset_in_page(start))); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 578 | start &= PAGE_MASK; |
| 579 | |
Jiri Slaby | 59e99e5 | 2010-03-05 13:41:44 -0800 | [diff] [blame] | 580 | lock_limit = rlimit(RLIMIT_MEMLOCK); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 581 | lock_limit >>= PAGE_SHIFT; |
Davidlohr Bueso | 1f1cd70 | 2014-01-21 15:49:16 -0800 | [diff] [blame] | 582 | locked = len >> PAGE_SHIFT; |
| 583 | |
Michel Lespinasse | d8ed45c | 2020-06-08 21:33:25 -0700 | [diff] [blame] | 584 | if (mmap_write_lock_killable(current->mm)) |
Michal Hocko | dc0ef0d | 2016-05-23 16:25:27 -0700 | [diff] [blame] | 585 | return -EINTR; |
Davidlohr Bueso | 1f1cd70 | 2014-01-21 15:49:16 -0800 | [diff] [blame] | 586 | |
| 587 | locked += current->mm->locked_vm; |
Simon Guo | 0cf2f6f | 2016-10-07 16:59:36 -0700 | [diff] [blame] | 588 | if ((locked > lock_limit) && (!capable(CAP_IPC_LOCK))) { |
| 589 | /* |
| 590 | * It is possible that the regions requested intersect with |
| 591 | * previously mlocked areas, that part area in "mm->locked_vm" |
| 592 | * should not be counted to new mlock increment count. So check |
| 593 | * and adjust locked count if necessary. |
| 594 | */ |
| 595 | locked -= count_mm_mlocked_page_nr(current->mm, |
| 596 | start, len); |
| 597 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 598 | |
| 599 | /* check against resource limits */ |
| 600 | if ((locked <= lock_limit) || capable(CAP_IPC_LOCK)) |
Eric B Munson | 1aab92ec | 2015-11-05 18:51:29 -0800 | [diff] [blame] | 601 | error = apply_vma_lock_flags(start, len, flags); |
Davidlohr Bueso | 1f1cd70 | 2014-01-21 15:49:16 -0800 | [diff] [blame] | 602 | |
Michel Lespinasse | d8ed45c | 2020-06-08 21:33:25 -0700 | [diff] [blame] | 603 | mmap_write_unlock(current->mm); |
Kirill A. Shutemov | c561259 | 2015-04-14 15:44:42 -0700 | [diff] [blame] | 604 | if (error) |
| 605 | return error; |
| 606 | |
| 607 | error = __mm_populate(start, len, 0); |
| 608 | if (error) |
| 609 | return __mlock_posix_error_return(error); |
| 610 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 611 | } |
| 612 | |
Eric B Munson | 1aab92ec | 2015-11-05 18:51:29 -0800 | [diff] [blame] | 613 | SYSCALL_DEFINE2(mlock, unsigned long, start, size_t, len) |
| 614 | { |
| 615 | return do_mlock(start, len, VM_LOCKED); |
| 616 | } |
| 617 | |
Eric B Munson | a8ca5d0 | 2015-11-05 18:51:33 -0800 | [diff] [blame] | 618 | SYSCALL_DEFINE3(mlock2, unsigned long, start, size_t, len, int, flags) |
| 619 | { |
Eric B Munson | b0f205c | 2015-11-05 18:51:39 -0800 | [diff] [blame] | 620 | vm_flags_t vm_flags = VM_LOCKED; |
| 621 | |
| 622 | if (flags & ~MLOCK_ONFAULT) |
Eric B Munson | a8ca5d0 | 2015-11-05 18:51:33 -0800 | [diff] [blame] | 623 | return -EINVAL; |
| 624 | |
Eric B Munson | b0f205c | 2015-11-05 18:51:39 -0800 | [diff] [blame] | 625 | if (flags & MLOCK_ONFAULT) |
| 626 | vm_flags |= VM_LOCKONFAULT; |
| 627 | |
| 628 | return do_mlock(start, len, vm_flags); |
Eric B Munson | a8ca5d0 | 2015-11-05 18:51:33 -0800 | [diff] [blame] | 629 | } |
| 630 | |
Heiko Carstens | 6a6160a | 2009-01-14 14:14:15 +0100 | [diff] [blame] | 631 | SYSCALL_DEFINE2(munlock, unsigned long, start, size_t, len) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 632 | { |
| 633 | int ret; |
| 634 | |
Andrey Konovalov | 057d3389 | 2019-09-25 16:48:30 -0700 | [diff] [blame] | 635 | start = untagged_addr(start); |
| 636 | |
Alexander Kuleshov | 8fd9e48 | 2015-11-05 18:46:49 -0800 | [diff] [blame] | 637 | len = PAGE_ALIGN(len + (offset_in_page(start))); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 638 | start &= PAGE_MASK; |
Davidlohr Bueso | 1f1cd70 | 2014-01-21 15:49:16 -0800 | [diff] [blame] | 639 | |
Michel Lespinasse | d8ed45c | 2020-06-08 21:33:25 -0700 | [diff] [blame] | 640 | if (mmap_write_lock_killable(current->mm)) |
Michal Hocko | dc0ef0d | 2016-05-23 16:25:27 -0700 | [diff] [blame] | 641 | return -EINTR; |
Eric B Munson | 1aab92ec | 2015-11-05 18:51:29 -0800 | [diff] [blame] | 642 | ret = apply_vma_lock_flags(start, len, 0); |
Michel Lespinasse | d8ed45c | 2020-06-08 21:33:25 -0700 | [diff] [blame] | 643 | mmap_write_unlock(current->mm); |
Davidlohr Bueso | 1f1cd70 | 2014-01-21 15:49:16 -0800 | [diff] [blame] | 644 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 645 | return ret; |
| 646 | } |
| 647 | |
Eric B Munson | b0f205c | 2015-11-05 18:51:39 -0800 | [diff] [blame] | 648 | /* |
| 649 | * Take the MCL_* flags passed into mlockall (or 0 if called from munlockall) |
| 650 | * and translate into the appropriate modifications to mm->def_flags and/or the |
| 651 | * flags for all current VMAs. |
| 652 | * |
| 653 | * There are a couple of subtleties with this. If mlockall() is called multiple |
| 654 | * times with different flags, the values do not necessarily stack. If mlockall |
| 655 | * is called once including the MCL_FUTURE flag and then a second time without |
| 656 | * it, VM_LOCKED and VM_LOCKONFAULT will be cleared from mm->def_flags. |
| 657 | */ |
Eric B Munson | 1aab92ec | 2015-11-05 18:51:29 -0800 | [diff] [blame] | 658 | static int apply_mlockall_flags(int flags) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 659 | { |
Liam R. Howlett | 37598f5 | 2023-01-20 11:26:19 -0500 | [diff] [blame] | 660 | VMA_ITERATOR(vmi, current->mm, 0); |
Zhiyuan Dai | 68d68ff | 2021-05-04 18:40:12 -0700 | [diff] [blame] | 661 | struct vm_area_struct *vma, *prev = NULL; |
Eric B Munson | b0f205c | 2015-11-05 18:51:39 -0800 | [diff] [blame] | 662 | vm_flags_t to_add = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 663 | |
Suren Baghdasaryan | e430a95 | 2023-01-26 11:37:48 -0800 | [diff] [blame] | 664 | current->mm->def_flags &= ~VM_LOCKED_MASK; |
Eric B Munson | b0f205c | 2015-11-05 18:51:39 -0800 | [diff] [blame] | 665 | if (flags & MCL_FUTURE) { |
Michel Lespinasse | 09a9f1d | 2013-03-28 16:26:23 -0700 | [diff] [blame] | 666 | current->mm->def_flags |= VM_LOCKED; |
Eric B Munson | 1aab92ec | 2015-11-05 18:51:29 -0800 | [diff] [blame] | 667 | |
Eric B Munson | b0f205c | 2015-11-05 18:51:39 -0800 | [diff] [blame] | 668 | if (flags & MCL_ONFAULT) |
| 669 | current->mm->def_flags |= VM_LOCKONFAULT; |
| 670 | |
| 671 | if (!(flags & MCL_CURRENT)) |
| 672 | goto out; |
| 673 | } |
| 674 | |
| 675 | if (flags & MCL_CURRENT) { |
| 676 | to_add |= VM_LOCKED; |
| 677 | if (flags & MCL_ONFAULT) |
| 678 | to_add |= VM_LOCKONFAULT; |
| 679 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 680 | |
Liam R. Howlett | 37598f5 | 2023-01-20 11:26:19 -0500 | [diff] [blame] | 681 | for_each_vma(vmi, vma) { |
KOSAKI Motohiro | ca16d14 | 2011-05-26 19:16:19 +0900 | [diff] [blame] | 682 | vm_flags_t newflags; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 683 | |
Suren Baghdasaryan | e430a95 | 2023-01-26 11:37:48 -0800 | [diff] [blame] | 684 | newflags = vma->vm_flags & ~VM_LOCKED_MASK; |
Eric B Munson | b0f205c | 2015-11-05 18:51:39 -0800 | [diff] [blame] | 685 | newflags |= to_add; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 686 | |
| 687 | /* Ignore errors */ |
Liam R. Howlett | 37598f5 | 2023-01-20 11:26:19 -0500 | [diff] [blame] | 688 | mlock_fixup(&vmi, vma, &prev, vma->vm_start, vma->vm_end, |
| 689 | newflags); |
Paul E. McKenney | 50d4fb7 | 2017-10-24 08:22:18 -0700 | [diff] [blame] | 690 | cond_resched(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 691 | } |
| 692 | out: |
| 693 | return 0; |
| 694 | } |
| 695 | |
Heiko Carstens | 3480b25 | 2009-01-14 14:14:16 +0100 | [diff] [blame] | 696 | SYSCALL_DEFINE1(mlockall, int, flags) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 697 | { |
| 698 | unsigned long lock_limit; |
Alexey Klimov | 86d2adcc | 2015-11-05 18:46:00 -0800 | [diff] [blame] | 699 | int ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 700 | |
Potyra, Stefan | dedca63 | 2019-06-13 15:55:55 -0700 | [diff] [blame] | 701 | if (!flags || (flags & ~(MCL_CURRENT | MCL_FUTURE | MCL_ONFAULT)) || |
| 702 | flags == MCL_ONFAULT) |
Alexey Klimov | 86d2adcc | 2015-11-05 18:46:00 -0800 | [diff] [blame] | 703 | return -EINVAL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 704 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 705 | if (!can_do_mlock()) |
Alexey Klimov | 86d2adcc | 2015-11-05 18:46:00 -0800 | [diff] [blame] | 706 | return -EPERM; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 707 | |
Jiri Slaby | 59e99e5 | 2010-03-05 13:41:44 -0800 | [diff] [blame] | 708 | lock_limit = rlimit(RLIMIT_MEMLOCK); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 709 | lock_limit >>= PAGE_SHIFT; |
| 710 | |
Michel Lespinasse | d8ed45c | 2020-06-08 21:33:25 -0700 | [diff] [blame] | 711 | if (mmap_write_lock_killable(current->mm)) |
Michal Hocko | dc0ef0d | 2016-05-23 16:25:27 -0700 | [diff] [blame] | 712 | return -EINTR; |
Davidlohr Bueso | 1f1cd70 | 2014-01-21 15:49:16 -0800 | [diff] [blame] | 713 | |
Michal Hocko | dc0ef0d | 2016-05-23 16:25:27 -0700 | [diff] [blame] | 714 | ret = -ENOMEM; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 715 | if (!(flags & MCL_CURRENT) || (current->mm->total_vm <= lock_limit) || |
| 716 | capable(CAP_IPC_LOCK)) |
Eric B Munson | 1aab92ec | 2015-11-05 18:51:29 -0800 | [diff] [blame] | 717 | ret = apply_mlockall_flags(flags); |
Michel Lespinasse | d8ed45c | 2020-06-08 21:33:25 -0700 | [diff] [blame] | 718 | mmap_write_unlock(current->mm); |
Michel Lespinasse | bebeb3d | 2013-02-22 16:32:37 -0800 | [diff] [blame] | 719 | if (!ret && (flags & MCL_CURRENT)) |
| 720 | mm_populate(0, TASK_SIZE); |
Alexey Klimov | 86d2adcc | 2015-11-05 18:46:00 -0800 | [diff] [blame] | 721 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 722 | return ret; |
| 723 | } |
| 724 | |
Heiko Carstens | 3480b25 | 2009-01-14 14:14:16 +0100 | [diff] [blame] | 725 | SYSCALL_DEFINE0(munlockall) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 726 | { |
| 727 | int ret; |
| 728 | |
Michel Lespinasse | d8ed45c | 2020-06-08 21:33:25 -0700 | [diff] [blame] | 729 | if (mmap_write_lock_killable(current->mm)) |
Michal Hocko | dc0ef0d | 2016-05-23 16:25:27 -0700 | [diff] [blame] | 730 | return -EINTR; |
Eric B Munson | 1aab92ec | 2015-11-05 18:51:29 -0800 | [diff] [blame] | 731 | ret = apply_mlockall_flags(0); |
Michel Lespinasse | d8ed45c | 2020-06-08 21:33:25 -0700 | [diff] [blame] | 732 | mmap_write_unlock(current->mm); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 733 | return ret; |
| 734 | } |
| 735 | |
| 736 | /* |
| 737 | * Objects with different lifetime than processes (SHM_LOCK and SHM_HUGETLB |
| 738 | * shm segments) get accounted against the user_struct instead. |
| 739 | */ |
| 740 | static DEFINE_SPINLOCK(shmlock_user_lock); |
| 741 | |
Alexey Gladkov | d7c9e99 | 2021-04-22 14:27:14 +0200 | [diff] [blame] | 742 | int user_shm_lock(size_t size, struct ucounts *ucounts) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 743 | { |
| 744 | unsigned long lock_limit, locked; |
Alexey Gladkov | d7c9e99 | 2021-04-22 14:27:14 +0200 | [diff] [blame] | 745 | long memlock; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 746 | int allowed = 0; |
| 747 | |
| 748 | locked = (size + PAGE_SIZE - 1) >> PAGE_SHIFT; |
Jiri Slaby | 59e99e5 | 2010-03-05 13:41:44 -0800 | [diff] [blame] | 749 | lock_limit = rlimit(RLIMIT_MEMLOCK); |
Miaohe Lin | e97824f | 2022-03-22 16:09:18 +0800 | [diff] [blame] | 750 | if (lock_limit != RLIM_INFINITY) |
| 751 | lock_limit >>= PAGE_SHIFT; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 752 | spin_lock(&shmlock_user_lock); |
Alexey Gladkov | d7c9e99 | 2021-04-22 14:27:14 +0200 | [diff] [blame] | 753 | memlock = inc_rlimit_ucounts(ucounts, UCOUNT_RLIMIT_MEMLOCK, locked); |
| 754 | |
Miaohe Lin | e97824f | 2022-03-22 16:09:18 +0800 | [diff] [blame] | 755 | if ((memlock == LONG_MAX || memlock > lock_limit) && !capable(CAP_IPC_LOCK)) { |
Alexey Gladkov | d7c9e99 | 2021-04-22 14:27:14 +0200 | [diff] [blame] | 756 | dec_rlimit_ucounts(ucounts, UCOUNT_RLIMIT_MEMLOCK, locked); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 757 | goto out; |
Alexey Gladkov | d7c9e99 | 2021-04-22 14:27:14 +0200 | [diff] [blame] | 758 | } |
| 759 | if (!get_ucounts(ucounts)) { |
| 760 | dec_rlimit_ucounts(ucounts, UCOUNT_RLIMIT_MEMLOCK, locked); |
Miaohe Lin | 5c2a956 | 2022-03-22 14:44:56 -0700 | [diff] [blame] | 761 | allowed = 0; |
Alexey Gladkov | d7c9e99 | 2021-04-22 14:27:14 +0200 | [diff] [blame] | 762 | goto out; |
| 763 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 764 | allowed = 1; |
| 765 | out: |
| 766 | spin_unlock(&shmlock_user_lock); |
| 767 | return allowed; |
| 768 | } |
| 769 | |
Alexey Gladkov | d7c9e99 | 2021-04-22 14:27:14 +0200 | [diff] [blame] | 770 | void user_shm_unlock(size_t size, struct ucounts *ucounts) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 771 | { |
| 772 | spin_lock(&shmlock_user_lock); |
Alexey Gladkov | d7c9e99 | 2021-04-22 14:27:14 +0200 | [diff] [blame] | 773 | 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] | 774 | spin_unlock(&shmlock_user_lock); |
Alexey Gladkov | d7c9e99 | 2021-04-22 14:27:14 +0200 | [diff] [blame] | 775 | put_ucounts(ucounts); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 776 | } |