diff options
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/proc/task_mmu.c | 47 |
1 files changed, 42 insertions, 5 deletions
diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c index 39d6412..a18e065 100644 --- a/fs/proc/task_mmu.c +++ b/fs/proc/task_mmu.c @@ -11,6 +11,7 @@ #include <linux/rmap.h> #include <linux/swap.h> #include <linux/swapops.h> +#include <linux/mmu_notifier.h> #include <asm/elf.h> #include <asm/uaccess.h> @@ -692,13 +693,32 @@ enum clear_refs_types { CLEAR_REFS_ALL = 1, CLEAR_REFS_ANON, CLEAR_REFS_MAPPED, + CLEAR_REFS_SOFT_DIRTY, CLEAR_REFS_LAST, }; struct clear_refs_private { struct vm_area_struct *vma; + enum clear_refs_types type; }; +static inline void clear_soft_dirty(struct vm_area_struct *vma, + unsigned long addr, pte_t *pte) +{ +#ifdef CONFIG_MEM_SOFT_DIRTY + /* + * The soft-dirty tracker uses #PF-s to catch writes + * to pages, so write-protect the pte as well. See the + * Documentation/vm/soft-dirty.txt for full description + * of how soft-dirty works. + */ + pte_t ptent = *pte; + ptent = pte_wrprotect(ptent); + ptent = pte_clear_flags(ptent, _PAGE_SOFT_DIRTY); + set_pte_at(vma->vm_mm, addr, pte, ptent); +#endif +} + static int clear_refs_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end, struct mm_walk *walk) { @@ -718,6 +738,11 @@ static int clear_refs_pte_range(pmd_t *pmd, unsigned long addr, if (!pte_present(ptent)) continue; + if (cp->type == CLEAR_REFS_SOFT_DIRTY) { + clear_soft_dirty(vma, addr, pte); + continue; + } + page = vm_normal_page(vma, addr, ptent); if (!page) continue; @@ -759,6 +784,7 @@ static ssize_t clear_refs_write(struct file *file, const char __user *buf, mm = get_task_mm(task); if (mm) { struct clear_refs_private cp = { + .type = type, }; struct mm_walk clear_refs_walk = { .pmd_entry = clear_refs_pte_range, @@ -766,6 +792,8 @@ static ssize_t clear_refs_write(struct file *file, const char __user *buf, .private = &cp, }; down_read(&mm->mmap_sem); + if (type == CLEAR_REFS_SOFT_DIRTY) + mmu_notifier_invalidate_range_start(mm, 0, -1); for (vma = mm->mmap; vma; vma = vma->vm_next) { cp.vma = vma; if (is_vm_hugetlb_page(vma)) @@ -786,6 +814,8 @@ static ssize_t clear_refs_write(struct file *file, const char __user *buf, walk_page_range(vma->vm_start, vma->vm_end, &clear_refs_walk); } + if (type == CLEAR_REFS_SOFT_DIRTY) + mmu_notifier_invalidate_range_end(mm, 0, -1); flush_tlb_mm(mm); up_read(&mm->mmap_sem); mmput(mm); @@ -827,6 +857,7 @@ struct pagemapread { /* in "new" pagemap pshift bits are occupied with more status bits */ #define PM_STATUS2(v2, x) (__PM_PSHIFT(v2 ? x : PAGE_SHIFT)) +#define __PM_SOFT_DIRTY (1LL) #define PM_PRESENT PM_STATUS(4LL) #define PM_SWAP PM_STATUS(2LL) #define PM_FILE PM_STATUS(1LL) @@ -868,6 +899,7 @@ static void pte_to_pagemap_entry(pagemap_entry_t *pme, struct pagemapread *pm, { u64 frame, flags; struct page *page = NULL; + int flags2 = 0; if (pte_present(pte)) { frame = pte_pfn(pte); @@ -888,13 +920,15 @@ static void pte_to_pagemap_entry(pagemap_entry_t *pme, struct pagemapread *pm, if (page && !PageAnon(page)) flags |= PM_FILE; + if (pte_soft_dirty(pte)) + flags2 |= __PM_SOFT_DIRTY; - *pme = make_pme(PM_PFRAME(frame) | PM_STATUS2(pm->v2, 0) | flags); + *pme = make_pme(PM_PFRAME(frame) | PM_STATUS2(pm->v2, flags2) | flags); } #ifdef CONFIG_TRANSPARENT_HUGEPAGE static void thp_pmd_to_pagemap_entry(pagemap_entry_t *pme, struct pagemapread *pm, - pmd_t pmd, int offset) + pmd_t pmd, int offset, int pmd_flags2) { /* * Currently pmd for thp is always present because thp can not be @@ -903,13 +937,13 @@ static void thp_pmd_to_pagemap_entry(pagemap_entry_t *pme, struct pagemapread *p */ if (pmd_present(pmd)) *pme = make_pme(PM_PFRAME(pmd_pfn(pmd) + offset) - | PM_STATUS2(pm->v2, 0) | PM_PRESENT); + | PM_STATUS2(pm->v2, pmd_flags2) | PM_PRESENT); else *pme = make_pme(PM_NOT_PRESENT(pm->v2)); } #else static inline void thp_pmd_to_pagemap_entry(pagemap_entry_t *pme, struct pagemapread *pm, - pmd_t pmd, int offset) + pmd_t pmd, int offset, int pmd_flags2) { } #endif @@ -926,12 +960,15 @@ static int pagemap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end, /* find the first VMA at or above 'addr' */ vma = find_vma(walk->mm, addr); if (vma && pmd_trans_huge_lock(pmd, vma) == 1) { + int pmd_flags2; + + pmd_flags2 = (pmd_soft_dirty(*pmd) ? __PM_SOFT_DIRTY : 0); for (; addr != end; addr += PAGE_SIZE) { unsigned long offset; offset = (addr & ~PAGEMAP_WALK_MASK) >> PAGE_SHIFT; - thp_pmd_to_pagemap_entry(&pme, pm, *pmd, offset); + thp_pmd_to_pagemap_entry(&pme, pm, *pmd, offset, pmd_flags2); err = add_to_pagemap(addr, &pme, pm); if (err) break; |