diff options
| -rw-r--r-- | include/linux/mm.h | 5 | ||||
| -rw-r--r-- | kernel/fork.c | 3 | ||||
| -rw-r--r-- | mm/debug.c | 1 | ||||
| -rw-r--r-- | mm/gup.c | 10 | ||||
| -rw-r--r-- | mm/huge_memory.c | 2 | ||||
| -rw-r--r-- | mm/hugetlb.c | 4 | ||||
| -rw-r--r-- | mm/mlock.c | 2 | ||||
| -rw-r--r-- | mm/mmap.c | 2 |
8 files changed, 21 insertions, 8 deletions
diff --git a/include/linux/mm.h b/include/linux/mm.h index 3c258f8eb9ae..906c46a05707 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -139,6 +139,7 @@ extern unsigned int kobjsize(const void *objp); #define VM_DONTCOPY 0x00020000 /* Do not copy this vma on fork */ #define VM_DONTEXPAND 0x00040000 /* Cannot expand with mremap() */ +#define VM_LOCKONFAULT 0x00080000 /* Lock the pages covered when they are faulted in */ #define VM_ACCOUNT 0x00100000 /* Is a VM accounted object */ #define VM_NORESERVE 0x00200000 /* should the VM suppress accounting */ #define VM_HUGETLB 0x00400000 /* Huge TLB Page VM */ @@ -202,6 +203,9 @@ extern unsigned int kobjsize(const void *objp); /* This mask defines which mm->def_flags a process can inherit its parent */ #define VM_INIT_DEF_MASK VM_NOHUGEPAGE +/* This mask is used to clear all the VMA flags used by mlock */ +#define VM_LOCKED_CLEAR_MASK (~(VM_LOCKED | VM_LOCKONFAULT)) + /* * mapping from the currently active vm_flags protection bits (the * low four bits) to a page protection mask.. @@ -2137,6 +2141,7 @@ static inline struct page *follow_page(struct vm_area_struct *vma, #define FOLL_NUMA 0x200 /* force NUMA hinting page fault */ #define FOLL_MIGRATION 0x400 /* wait for page to replace migration entry */ #define FOLL_TRIED 0x800 /* a retry, previous pass started an IO */ +#define FOLL_MLOCK 0x1000 /* lock present pages */ typedef int (*pte_fn_t)(pte_t *pte, pgtable_t token, unsigned long addr, void *data); diff --git a/kernel/fork.c b/kernel/fork.c index 6ac894244d39..a30fae45b486 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -454,7 +454,8 @@ static int dup_mmap(struct mm_struct *mm, struct mm_struct *oldmm) tmp->vm_mm = mm; if (anon_vma_fork(tmp, mpnt)) goto fail_nomem_anon_vma_fork; - tmp->vm_flags &= ~(VM_LOCKED|VM_UFFD_MISSING|VM_UFFD_WP); + tmp->vm_flags &= + ~(VM_LOCKED|VM_LOCKONFAULT|VM_UFFD_MISSING|VM_UFFD_WP); tmp->vm_next = tmp->vm_prev = NULL; tmp->vm_userfaultfd_ctx = NULL_VM_UFFD_CTX; file = tmp->vm_file; diff --git a/mm/debug.c b/mm/debug.c index 6c1b3ea61bfd..e784110fb51d 100644 --- a/mm/debug.c +++ b/mm/debug.c @@ -125,6 +125,7 @@ static const struct trace_print_flags vmaflags_names[] = { {VM_GROWSDOWN, "growsdown" }, {VM_PFNMAP, "pfnmap" }, {VM_DENYWRITE, "denywrite" }, + {VM_LOCKONFAULT, "lockonfault" }, {VM_LOCKED, "locked" }, {VM_IO, "io" }, {VM_SEQ_READ, "seqread" }, @@ -129,7 +129,7 @@ retry: */ mark_page_accessed(page); } - if ((flags & FOLL_POPULATE) && (vma->vm_flags & VM_LOCKED)) { + if ((flags & FOLL_MLOCK) && (vma->vm_flags & VM_LOCKED)) { /* * The preliminary mapping check is mainly to avoid the * pointless overhead of lock_page on the ZERO_PAGE @@ -299,6 +299,9 @@ static int faultin_page(struct task_struct *tsk, struct vm_area_struct *vma, unsigned int fault_flags = 0; int ret; + /* mlock all present pages, but do not fault in new pages */ + if ((*flags & (FOLL_POPULATE | FOLL_MLOCK)) == FOLL_MLOCK) + return -ENOENT; /* For mm_populate(), just skip the stack guard page. */ if ((*flags & FOLL_POPULATE) && (stack_guard_page_start(vma, address) || @@ -890,7 +893,10 @@ long populate_vma_page_range(struct vm_area_struct *vma, VM_BUG_ON_VMA(end > vma->vm_end, vma); VM_BUG_ON_MM(!rwsem_is_locked(&mm->mmap_sem), mm); - gup_flags = FOLL_TOUCH | FOLL_POPULATE; + gup_flags = FOLL_TOUCH | FOLL_POPULATE | FOLL_MLOCK; + if (vma->vm_flags & VM_LOCKONFAULT) + gup_flags &= ~FOLL_POPULATE; + /* * We want to touch writable mappings with a write fault in order * to break COW, except for shared mappings because these don't COW diff --git a/mm/huge_memory.c b/mm/huge_memory.c index 3fd0311c3ba7..f5c08b46fef8 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -1307,7 +1307,7 @@ struct page *follow_trans_huge_pmd(struct vm_area_struct *vma, pmd, _pmd, 1)) update_mmu_cache_pmd(vma, addr, pmd); } - if ((flags & FOLL_POPULATE) && (vma->vm_flags & VM_LOCKED)) { + if ((flags & FOLL_MLOCK) && (vma->vm_flags & VM_LOCKED)) { if (page->mapping && trylock_page(page)) { lru_add_drain(); if (page->mapping) diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 241de2712b36..74ef0c6a25dd 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -4137,8 +4137,8 @@ static unsigned long page_table_shareable(struct vm_area_struct *svma, unsigned long s_end = sbase + PUD_SIZE; /* Allow segments to share if only one is marked locked */ - unsigned long vm_flags = vma->vm_flags & ~VM_LOCKED; - unsigned long svm_flags = svma->vm_flags & ~VM_LOCKED; + unsigned long vm_flags = vma->vm_flags & VM_LOCKED_CLEAR_MASK; + unsigned long svm_flags = svma->vm_flags & VM_LOCKED_CLEAR_MASK; /* * match the virtual addresses, permission and the alignment of the diff --git a/mm/mlock.c b/mm/mlock.c index 35dcf8fa7195..ca3894113b97 100644 --- a/mm/mlock.c +++ b/mm/mlock.c @@ -422,7 +422,7 @@ static unsigned long __munlock_pagevec_fill(struct pagevec *pvec, void munlock_vma_pages_range(struct vm_area_struct *vma, unsigned long start, unsigned long end) { - vma->vm_flags &= ~VM_LOCKED; + vma->vm_flags &= VM_LOCKED_CLEAR_MASK; while (start < end) { struct page *page = NULL; diff --git a/mm/mmap.c b/mm/mmap.c index 220effde8ea3..2ce04a649f6b 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -1661,7 +1661,7 @@ out: vma == get_gate_vma(current->mm))) mm->locked_vm += (len >> PAGE_SHIFT); else - vma->vm_flags &= ~VM_LOCKED; + vma->vm_flags &= VM_LOCKED_CLEAR_MASK; } if (file) |