*/
#include <linux/mm.h>
+#include <linux/sched/mm.h>
+#include <linux/sched/task.h>
#include <linux/pagemap.h>
#include <linux/swap.h>
#include <linux/swapops.h>
try_to_unmap_flush();
}
-static void set_tlb_ubc_flush_pending(struct mm_struct *mm,
- struct page *page, bool writable)
+static void set_tlb_ubc_flush_pending(struct mm_struct *mm, bool writable)
{
struct tlbflush_unmap_batch *tlb_ubc = ¤t->tlb_ubc;
return should_defer;
}
#else
-static void set_tlb_ubc_flush_pending(struct mm_struct *mm,
- struct page *page, bool writable)
+static void set_tlb_ubc_flush_pending(struct mm_struct *mm, bool writable)
{
}
pmd_t *mm_find_pmd(struct mm_struct *mm, unsigned long address)
{
pgd_t *pgd;
+ p4d_t *p4d;
pud_t *pud;
pmd_t *pmd = NULL;
pmd_t pmde;
if (!pgd_present(*pgd))
goto out;
- pud = pud_offset(pgd, address);
+ p4d = p4d_offset(pgd, address);
+ if (!p4d_present(*p4d))
+ goto out;
+
+ pud = pud_offset(p4d, address);
if (!pud_present(*pud))
goto out;
return pmd;
}
-/*
- * Check that @page is mapped at @address into @mm.
- *
- * If @sync is false, page_check_address may perform a racy check to avoid
- * the page table lock when the pte is not present (helpful when reclaiming
- * highly shared pages).
- *
- * On success returns with pte mapped and locked.
- */
-pte_t *__page_check_address(struct page *page, struct mm_struct *mm,
- unsigned long address, spinlock_t **ptlp, int sync)
-{
- pmd_t *pmd;
- pte_t *pte;
- spinlock_t *ptl;
-
- if (unlikely(PageHuge(page))) {
- /* when pud is not present, pte will be NULL */
- pte = huge_pte_offset(mm, address);
- if (!pte)
- return NULL;
-
- ptl = huge_pte_lockptr(page_hstate(page), mm, pte);
- goto check;
- }
-
- pmd = mm_find_pmd(mm, address);
- if (!pmd)
- return NULL;
-
- pte = pte_offset_map(pmd, address);
- /* Make a quick check before getting the lock */
- if (!sync && !pte_present(*pte)) {
- pte_unmap(pte);
- return NULL;
- }
-
- ptl = pte_lockptr(mm, pmd);
-check:
- spin_lock(ptl);
- if (pte_present(*pte) && page_to_pfn(page) == pte_pfn(*pte)) {
- *ptlp = ptl;
- return pte;
- }
- pte_unmap_unlock(pte, ptl);
- return NULL;
-}
-
-/**
- * page_mapped_in_vma - check whether a page is really mapped in a VMA
- * @page: the page to test
- * @vma: the VMA to test
- *
- * Returns 1 if the page is mapped into the page tables of the VMA, 0
- * if the page is not mapped into the page tables of this VMA. Only
- * valid for normal file or anonymous VMAs.
- */
-int page_mapped_in_vma(struct page *page, struct vm_area_struct *vma)
-{
- unsigned long address;
- pte_t *pte;
- spinlock_t *ptl;
-
- address = __vma_address(page, vma);
- if (unlikely(address < vma->vm_start || address >= vma->vm_end))
- return 0;
- pte = page_check_address(page, vma->vm_mm, address, &ptl, 1);
- if (!pte) /* the page is not in this mm */
- return 0;
- pte_unmap_unlock(pte, ptl);
-
- return 1;
-}
-
-#ifdef CONFIG_TRANSPARENT_HUGEPAGE
-/*
- * Check that @page is mapped at @address into @mm. In contrast to
- * page_check_address(), this function can handle transparent huge pages.
- *
- * On success returns true with pte mapped and locked. For PMD-mapped
- * transparent huge pages *@ptep is set to NULL.
- */
-bool page_check_address_transhuge(struct page *page, struct mm_struct *mm,
- unsigned long address, pmd_t **pmdp,
- pte_t **ptep, spinlock_t **ptlp)
-{
- pgd_t *pgd;
- pud_t *pud;
- pmd_t *pmd;
- pte_t *pte;
- spinlock_t *ptl;
-
- if (unlikely(PageHuge(page))) {
- /* when pud is not present, pte will be NULL */
- pte = huge_pte_offset(mm, address);
- if (!pte)
- return false;
-
- ptl = huge_pte_lockptr(page_hstate(page), mm, pte);
- pmd = NULL;
- goto check_pte;
- }
-
- pgd = pgd_offset(mm, address);
- if (!pgd_present(*pgd))
- return false;
- pud = pud_offset(pgd, address);
- if (!pud_present(*pud))
- return false;
- pmd = pmd_offset(pud, address);
-
- if (pmd_trans_huge(*pmd)) {
- ptl = pmd_lock(mm, pmd);
- if (!pmd_present(*pmd))
- goto unlock_pmd;
- if (unlikely(!pmd_trans_huge(*pmd))) {
- spin_unlock(ptl);
- goto map_pte;
- }
-
- if (pmd_page(*pmd) != page)
- goto unlock_pmd;
-
- pte = NULL;
- goto found;
-unlock_pmd:
- spin_unlock(ptl);
- return false;
- } else {
- pmd_t pmde = *pmd;
-
- barrier();
- if (!pmd_present(pmde) || pmd_trans_huge(pmde))
- return false;
- }
-map_pte:
- pte = pte_offset_map(pmd, address);
- if (!pte_present(*pte)) {
- pte_unmap(pte);
- return false;
- }
-
- ptl = pte_lockptr(mm, pmd);
-check_pte:
- spin_lock(ptl);
-
- if (!pte_present(*pte)) {
- pte_unmap_unlock(pte, ptl);
- return false;
- }
-
- /* THP can be referenced by any subpage */
- if (pte_pfn(*pte) - page_to_pfn(page) >= hpage_nr_pages(page)) {
- pte_unmap_unlock(pte, ptl);
- return false;
- }
-found:
- *ptep = pte;
- *pmdp = pmd;
- *ptlp = ptl;
- return true;
-}
-#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
-
struct page_referenced_arg {
int mapcount;
int referenced;
/*
* arg: page_referenced_arg will be passed
*/
-static int page_referenced_one(struct page *page, struct vm_area_struct *vma,
+static bool page_referenced_one(struct page *page, struct vm_area_struct *vma,
unsigned long address, void *arg)
{
- struct mm_struct *mm = vma->vm_mm;
struct page_referenced_arg *pra = arg;
- pmd_t *pmd;
- pte_t *pte;
- spinlock_t *ptl;
+ struct page_vma_mapped_walk pvmw = {
+ .page = page,
+ .vma = vma,
+ .address = address,
+ };
int referenced = 0;
- if (!page_check_address_transhuge(page, mm, address, &pmd, &pte, &ptl))
- return SWAP_AGAIN;
+ while (page_vma_mapped_walk(&pvmw)) {
+ address = pvmw.address;
- if (vma->vm_flags & VM_LOCKED) {
- if (pte)
- pte_unmap(pte);
- spin_unlock(ptl);
- pra->vm_flags |= VM_LOCKED;
- return SWAP_FAIL; /* To break the loop */
- }
+ if (vma->vm_flags & VM_LOCKED) {
+ page_vma_mapped_walk_done(&pvmw);
+ pra->vm_flags |= VM_LOCKED;
+ return false; /* To break the loop */
+ }
- if (pte) {
- if (ptep_clear_flush_young_notify(vma, address, pte)) {
- /*
- * Don't treat a reference through a sequentially read
- * mapping as such. If the page has been used in
- * another mapping, we will catch it; if this other
- * mapping is already gone, the unmap path will have
- * set PG_referenced or activated the page.
- */
- if (likely(!(vma->vm_flags & VM_SEQ_READ)))
+ if (pvmw.pte) {
+ if (ptep_clear_flush_young_notify(vma, address,
+ pvmw.pte)) {
+ /*
+ * Don't treat a reference through
+ * a sequentially read mapping as such.
+ * If the page has been used in another mapping,
+ * we will catch it; if this other mapping is
+ * already gone, the unmap path will have set
+ * PG_referenced or activated the page.
+ */
+ if (likely(!(vma->vm_flags & VM_SEQ_READ)))
+ referenced++;
+ }
+ } else if (IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE)) {
+ if (pmdp_clear_flush_young_notify(vma, address,
+ pvmw.pmd))
referenced++;
+ } else {
+ /* unexpected pmd-mapped page? */
+ WARN_ON_ONCE(1);
}
- pte_unmap(pte);
- } else if (IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE)) {
- if (pmdp_clear_flush_young_notify(vma, address, pmd))
- referenced++;
- } else {
- /* unexpected pmd-mapped page? */
- WARN_ON_ONCE(1);
+
+ pra->mapcount--;
}
- spin_unlock(ptl);
if (referenced)
clear_page_idle(page);
pra->vm_flags |= vma->vm_flags;
}
- pra->mapcount--;
if (!pra->mapcount)
- return SWAP_SUCCESS; /* To break the loop */
+ return false; /* To break the loop */
- return SWAP_AGAIN;
+ return true;
}
static bool invalid_page_referenced_vma(struct vm_area_struct *vma, void *arg)
struct mem_cgroup *memcg,
unsigned long *vm_flags)
{
- int ret;
int we_locked = 0;
struct page_referenced_arg pra = {
.mapcount = total_mapcount(page),
rwc.invalid_vma = invalid_page_referenced_vma;
}
- ret = rmap_walk(page, &rwc);
+ rmap_walk(page, &rwc);
*vm_flags = pra.vm_flags;
if (we_locked)
return pra.referenced;
}
-static int page_mkclean_one(struct page *page, struct vm_area_struct *vma,
+static bool page_mkclean_one(struct page *page, struct vm_area_struct *vma,
unsigned long address, void *arg)
{
- struct mm_struct *mm = vma->vm_mm;
- pte_t *pte;
- spinlock_t *ptl;
- int ret = 0;
+ struct page_vma_mapped_walk pvmw = {
+ .page = page,
+ .vma = vma,
+ .address = address,
+ .flags = PVMW_SYNC,
+ };
int *cleaned = arg;
- pte = page_check_address(page, mm, address, &ptl, 1);
- if (!pte)
- goto out;
-
- if (pte_dirty(*pte) || pte_write(*pte)) {
- pte_t entry;
+ while (page_vma_mapped_walk(&pvmw)) {
+ int ret = 0;
+ address = pvmw.address;
+ if (pvmw.pte) {
+ pte_t entry;
+ pte_t *pte = pvmw.pte;
+
+ if (!pte_dirty(*pte) && !pte_write(*pte))
+ continue;
+
+ flush_cache_page(vma, address, pte_pfn(*pte));
+ entry = ptep_clear_flush(vma, address, pte);
+ entry = pte_wrprotect(entry);
+ entry = pte_mkclean(entry);
+ set_pte_at(vma->vm_mm, address, pte, entry);
+ ret = 1;
+ } else {
+#ifdef CONFIG_TRANSPARENT_HUGE_PAGECACHE
+ pmd_t *pmd = pvmw.pmd;
+ pmd_t entry;
+
+ if (!pmd_dirty(*pmd) && !pmd_write(*pmd))
+ continue;
+
+ flush_cache_page(vma, address, page_to_pfn(page));
+ entry = pmdp_huge_clear_flush(vma, address, pmd);
+ entry = pmd_wrprotect(entry);
+ entry = pmd_mkclean(entry);
+ set_pmd_at(vma->vm_mm, address, pmd, entry);
+ ret = 1;
+#else
+ /* unexpected pmd-mapped page? */
+ WARN_ON_ONCE(1);
+#endif
+ }
- flush_cache_page(vma, address, pte_pfn(*pte));
- entry = ptep_clear_flush(vma, address, pte);
- entry = pte_wrprotect(entry);
- entry = pte_mkclean(entry);
- set_pte_at(mm, address, pte, entry);
- ret = 1;
+ if (ret) {
+ mmu_notifier_invalidate_page(vma->vm_mm, address);
+ (*cleaned)++;
+ }
}
- pte_unmap_unlock(pte, ptl);
-
- if (ret) {
- mmu_notifier_invalidate_page(mm, address);
- (*cleaned)++;
- }
-out:
- return SWAP_AGAIN;
+ return true;
}
static bool invalid_mkclean_vma(struct vm_area_struct *vma, void *arg)
goto out;
}
__mod_node_page_state(page_pgdat(page), NR_FILE_MAPPED, nr);
- mem_cgroup_inc_page_stat(page, MEM_CGROUP_STAT_FILE_MAPPED);
+ mod_memcg_page_state(page, NR_FILE_MAPPED, nr);
out:
unlock_page_memcg(page);
}
* pte lock(a spinlock) is held, which implies preemption disabled.
*/
__mod_node_page_state(page_pgdat(page), NR_FILE_MAPPED, -nr);
- mem_cgroup_dec_page_stat(page, MEM_CGROUP_STAT_FILE_MAPPED);
+ mod_memcg_page_state(page, NR_FILE_MAPPED, -nr);
if (unlikely(PageMlocked(page)))
clear_page_mlock(page);
*/
}
-struct rmap_private {
- enum ttu_flags flags;
- int lazyfreed;
-};
-
/*
* @arg: enum ttu_flags will be passed to this argument
*/
-static int try_to_unmap_one(struct page *page, struct vm_area_struct *vma,
+static bool try_to_unmap_one(struct page *page, struct vm_area_struct *vma,
unsigned long address, void *arg)
{
struct mm_struct *mm = vma->vm_mm;
- pte_t *pte;
+ struct page_vma_mapped_walk pvmw = {
+ .page = page,
+ .vma = vma,
+ .address = address,
+ };
pte_t pteval;
- spinlock_t *ptl;
- int ret = SWAP_AGAIN;
- struct rmap_private *rp = arg;
- enum ttu_flags flags = rp->flags;
+ struct page *subpage;
+ bool ret = true;
+ enum ttu_flags flags = (enum ttu_flags)arg;
/* munlock has nothing to gain from examining un-locked vmas */
if ((flags & TTU_MUNLOCK) && !(vma->vm_flags & VM_LOCKED))
- goto out;
+ return true;
if (flags & TTU_SPLIT_HUGE_PMD) {
split_huge_pmd_address(vma, address,
flags & TTU_MIGRATION, page);
- /* check if we have anything to do after split */
- if (page_mapcount(page) == 0)
- goto out;
}
- pte = page_check_address(page, mm, address, &ptl,
- PageTransCompound(page));
- if (!pte)
- goto out;
-
- /*
- * If the page is mlock()d, we cannot swap it out.
- * If it's recently referenced (perhaps page_referenced
- * skipped over this mm) then we should reactivate it.
- */
- if (!(flags & TTU_IGNORE_MLOCK)) {
- if (vma->vm_flags & VM_LOCKED) {
- /* PTE-mapped THP are never mlocked */
- if (!PageTransCompound(page)) {
- /*
- * Holding pte lock, we do *not* need
- * mmap_sem here
- */
- mlock_vma_page(page);
+ while (page_vma_mapped_walk(&pvmw)) {
+ /*
+ * If the page is mlock()d, we cannot swap it out.
+ * If it's recently referenced (perhaps page_referenced
+ * skipped over this mm) then we should reactivate it.
+ */
+ if (!(flags & TTU_IGNORE_MLOCK)) {
+ if (vma->vm_flags & VM_LOCKED) {
+ /* PTE-mapped THP are never mlocked */
+ if (!PageTransCompound(page)) {
+ /*
+ * Holding pte lock, we do *not* need
+ * mmap_sem here
+ */
+ mlock_vma_page(page);
+ }
+ ret = false;
+ page_vma_mapped_walk_done(&pvmw);
+ break;
}
- ret = SWAP_MLOCK;
- goto out_unmap;
+ if (flags & TTU_MUNLOCK)
+ continue;
}
- if (flags & TTU_MUNLOCK)
- goto out_unmap;
- }
- if (!(flags & TTU_IGNORE_ACCESS)) {
- if (ptep_clear_flush_young_notify(vma, address, pte)) {
- ret = SWAP_FAIL;
- goto out_unmap;
- }
- }
- /* Nuke the page table entry. */
- flush_cache_page(vma, address, page_to_pfn(page));
- if (should_defer_flush(mm, flags)) {
- /*
- * We clear the PTE but do not flush so potentially a remote
- * CPU could still be writing to the page. If the entry was
- * previously clean then the architecture must guarantee that
- * a clear->dirty transition on a cached TLB entry is written
- * through and traps if the PTE is unmapped.
- */
- pteval = ptep_get_and_clear(mm, address, pte);
+ /* Unexpected PMD-mapped THP? */
+ VM_BUG_ON_PAGE(!pvmw.pte, page);
+
+ subpage = page - page_to_pfn(page) + pte_pfn(*pvmw.pte);
+ address = pvmw.address;
- set_tlb_ubc_flush_pending(mm, page, pte_dirty(pteval));
- } else {
- pteval = ptep_clear_flush(vma, address, pte);
- }
- /* Move the dirty bit to the physical page now the pte is gone. */
- if (pte_dirty(pteval))
- set_page_dirty(page);
+ if (!(flags & TTU_IGNORE_ACCESS)) {
+ if (ptep_clear_flush_young_notify(vma, address,
+ pvmw.pte)) {
+ ret = false;
+ page_vma_mapped_walk_done(&pvmw);
+ break;
+ }
+ }
- /* Update high watermark before we lower rss */
- update_hiwater_rss(mm);
+ /* Nuke the page table entry. */
+ flush_cache_page(vma, address, pte_pfn(*pvmw.pte));
+ if (should_defer_flush(mm, flags)) {
+ /*
+ * We clear the PTE but do not flush so potentially
+ * a remote CPU could still be writing to the page.
+ * If the entry was previously clean then the
+ * architecture must guarantee that a clear->dirty
+ * transition on a cached TLB entry is written through
+ * and traps if the PTE is unmapped.
+ */
+ pteval = ptep_get_and_clear(mm, address, pvmw.pte);
- if (PageHWPoison(page) && !(flags & TTU_IGNORE_HWPOISON)) {
- if (PageHuge(page)) {
- hugetlb_count_sub(1 << compound_order(page), mm);
+ set_tlb_ubc_flush_pending(mm, pte_dirty(pteval));
} else {
- dec_mm_counter(mm, mm_counter(page));
+ pteval = ptep_clear_flush(vma, address, pvmw.pte);
}
- set_pte_at(mm, address, pte,
- swp_entry_to_pte(make_hwpoison_entry(page)));
- } else if (pte_unused(pteval)) {
- /*
- * The guest indicated that the page content is of no
- * interest anymore. Simply discard the pte, vmscan
- * will take care of the rest.
- */
- dec_mm_counter(mm, mm_counter(page));
- } else if (IS_ENABLED(CONFIG_MIGRATION) && (flags & TTU_MIGRATION)) {
- swp_entry_t entry;
- pte_t swp_pte;
- /*
- * Store the pfn of the page in a special migration
- * pte. do_swap_page() will wait until the migration
- * pte is removed and then restart fault handling.
- */
- entry = make_migration_entry(page, pte_write(pteval));
- swp_pte = swp_entry_to_pte(entry);
- if (pte_soft_dirty(pteval))
- swp_pte = pte_swp_mksoft_dirty(swp_pte);
- set_pte_at(mm, address, pte, swp_pte);
- } else if (PageAnon(page)) {
- swp_entry_t entry = { .val = page_private(page) };
- pte_t swp_pte;
- /*
- * Store the swap location in the pte.
- * See handle_pte_fault() ...
- */
- VM_BUG_ON_PAGE(!PageSwapCache(page), page);
- if (!PageDirty(page) && (flags & TTU_LZFREE)) {
- /* It's a freeable page by MADV_FREE */
- dec_mm_counter(mm, MM_ANONPAGES);
- rp->lazyfreed++;
- goto discard;
- }
+ /* Move the dirty bit to the page. Now the pte is gone. */
+ if (pte_dirty(pteval))
+ set_page_dirty(page);
- if (swap_duplicate(entry) < 0) {
- set_pte_at(mm, address, pte, pteval);
- ret = SWAP_FAIL;
- goto out_unmap;
- }
- if (list_empty(&mm->mmlist)) {
- spin_lock(&mmlist_lock);
- if (list_empty(&mm->mmlist))
- list_add(&mm->mmlist, &init_mm.mmlist);
- spin_unlock(&mmlist_lock);
- }
- dec_mm_counter(mm, MM_ANONPAGES);
- inc_mm_counter(mm, MM_SWAPENTS);
- swp_pte = swp_entry_to_pte(entry);
- if (pte_soft_dirty(pteval))
- swp_pte = pte_swp_mksoft_dirty(swp_pte);
- set_pte_at(mm, address, pte, swp_pte);
- } else
- dec_mm_counter(mm, mm_counter_file(page));
+ /* Update high watermark before we lower rss */
+ update_hiwater_rss(mm);
-discard:
- page_remove_rmap(page, PageHuge(page));
- put_page(page);
+ if (PageHWPoison(page) && !(flags & TTU_IGNORE_HWPOISON)) {
+ if (PageHuge(page)) {
+ int nr = 1 << compound_order(page);
+ hugetlb_count_sub(nr, mm);
+ } else {
+ dec_mm_counter(mm, mm_counter(page));
+ }
+
+ pteval = swp_entry_to_pte(make_hwpoison_entry(subpage));
+ set_pte_at(mm, address, pvmw.pte, pteval);
+ } else if (pte_unused(pteval)) {
+ /*
+ * The guest indicated that the page content is of no
+ * interest anymore. Simply discard the pte, vmscan
+ * will take care of the rest.
+ */
+ dec_mm_counter(mm, mm_counter(page));
+ } else if (IS_ENABLED(CONFIG_MIGRATION) &&
+ (flags & TTU_MIGRATION)) {
+ swp_entry_t entry;
+ pte_t swp_pte;
+ /*
+ * Store the pfn of the page in a special migration
+ * pte. do_swap_page() will wait until the migration
+ * pte is removed and then restart fault handling.
+ */
+ entry = make_migration_entry(subpage,
+ pte_write(pteval));
+ swp_pte = swp_entry_to_pte(entry);
+ if (pte_soft_dirty(pteval))
+ swp_pte = pte_swp_mksoft_dirty(swp_pte);
+ set_pte_at(mm, address, pvmw.pte, swp_pte);
+ } else if (PageAnon(page)) {
+ swp_entry_t entry = { .val = page_private(subpage) };
+ pte_t swp_pte;
+ /*
+ * Store the swap location in the pte.
+ * See handle_pte_fault() ...
+ */
+ if (unlikely(PageSwapBacked(page) != PageSwapCache(page))) {
+ WARN_ON_ONCE(1);
+ ret = false;
+ page_vma_mapped_walk_done(&pvmw);
+ break;
+ }
+
+ /* MADV_FREE page check */
+ if (!PageSwapBacked(page)) {
+ if (!PageDirty(page)) {
+ dec_mm_counter(mm, MM_ANONPAGES);
+ goto discard;
+ }
+
+ /*
+ * If the page was redirtied, it cannot be
+ * discarded. Remap the page to page table.
+ */
+ set_pte_at(mm, address, pvmw.pte, pteval);
+ SetPageSwapBacked(page);
+ ret = false;
+ page_vma_mapped_walk_done(&pvmw);
+ break;
+ }
-out_unmap:
- pte_unmap_unlock(pte, ptl);
- if (ret != SWAP_FAIL && ret != SWAP_MLOCK && !(flags & TTU_MUNLOCK))
+ if (swap_duplicate(entry) < 0) {
+ set_pte_at(mm, address, pvmw.pte, pteval);
+ ret = false;
+ page_vma_mapped_walk_done(&pvmw);
+ break;
+ }
+ if (list_empty(&mm->mmlist)) {
+ spin_lock(&mmlist_lock);
+ if (list_empty(&mm->mmlist))
+ list_add(&mm->mmlist, &init_mm.mmlist);
+ spin_unlock(&mmlist_lock);
+ }
+ dec_mm_counter(mm, MM_ANONPAGES);
+ inc_mm_counter(mm, MM_SWAPENTS);
+ swp_pte = swp_entry_to_pte(entry);
+ if (pte_soft_dirty(pteval))
+ swp_pte = pte_swp_mksoft_dirty(swp_pte);
+ set_pte_at(mm, address, pvmw.pte, swp_pte);
+ } else
+ dec_mm_counter(mm, mm_counter_file(page));
+discard:
+ page_remove_rmap(subpage, PageHuge(page));
+ put_page(page);
mmu_notifier_invalidate_page(mm, address);
-out:
+ }
return ret;
}
static int page_mapcount_is_zero(struct page *page)
{
- return !page_mapcount(page);
+ return !total_mapcount(page);
}
/**
*
* Tries to remove all the page table entries which are mapping this
* page, used in the pageout path. Caller must hold the page lock.
- * Return values are:
*
- * SWAP_SUCCESS - we succeeded in removing all mappings
- * SWAP_AGAIN - we missed a mapping, try again later
- * SWAP_FAIL - the page is unswappable
- * SWAP_MLOCK - page is mlocked.
+ * If unmap is successful, return true. Otherwise, false.
*/
-int try_to_unmap(struct page *page, enum ttu_flags flags)
+bool try_to_unmap(struct page *page, enum ttu_flags flags)
{
- int ret;
- struct rmap_private rp = {
- .flags = flags,
- .lazyfreed = 0,
- };
-
struct rmap_walk_control rwc = {
.rmap_one = try_to_unmap_one,
- .arg = &rp,
+ .arg = (void *)flags,
.done = page_mapcount_is_zero,
.anon_lock = page_lock_anon_vma_read,
};
rwc.invalid_vma = invalid_migration_vma;
if (flags & TTU_RMAP_LOCKED)
- ret = rmap_walk_locked(page, &rwc);
+ rmap_walk_locked(page, &rwc);
else
- ret = rmap_walk(page, &rwc);
+ rmap_walk(page, &rwc);
- if (ret != SWAP_MLOCK && !page_mapcount(page)) {
- ret = SWAP_SUCCESS;
- if (rp.lazyfreed && !PageDirty(page))
- ret = SWAP_LZFREE;
- }
- return ret;
+ return !page_mapcount(page) ? true : false;
}
static int page_not_mapped(struct page *page)
* Called from munlock code. Checks all of the VMAs mapping the page
* to make sure nobody else has this page mlocked. The page will be
* returned with PG_mlocked cleared if no other vmas have it mlocked.
- *
- * Return values are:
- *
- * SWAP_AGAIN - no vma is holding page mlocked, or,
- * SWAP_AGAIN - page mapped in mlocked vma -- couldn't acquire mmap sem
- * SWAP_FAIL - page cannot be located at present
- * SWAP_MLOCK - page is now mlocked.
*/
-int try_to_munlock(struct page *page)
-{
- int ret;
- struct rmap_private rp = {
- .flags = TTU_MUNLOCK,
- .lazyfreed = 0,
- };
+void try_to_munlock(struct page *page)
+{
struct rmap_walk_control rwc = {
.rmap_one = try_to_unmap_one,
- .arg = &rp,
+ .arg = (void *)TTU_MUNLOCK,
.done = page_not_mapped,
.anon_lock = page_lock_anon_vma_read,
};
VM_BUG_ON_PAGE(!PageLocked(page) || PageLRU(page), page);
+ VM_BUG_ON_PAGE(PageCompound(page) && PageDoubleMap(page), page);
- ret = rmap_walk(page, &rwc);
- return ret;
+ rmap_walk(page, &rwc);
}
void __put_anon_vma(struct anon_vma *anon_vma)
* vm_flags for that VMA. That should be OK, because that vma shouldn't be
* LOCKED.
*/
-static int rmap_walk_anon(struct page *page, struct rmap_walk_control *rwc,
+static void rmap_walk_anon(struct page *page, struct rmap_walk_control *rwc,
bool locked)
{
struct anon_vma *anon_vma;
- pgoff_t pgoff;
+ pgoff_t pgoff_start, pgoff_end;
struct anon_vma_chain *avc;
- int ret = SWAP_AGAIN;
if (locked) {
anon_vma = page_anon_vma(page);
anon_vma = rmap_walk_anon_lock(page, rwc);
}
if (!anon_vma)
- return ret;
+ return;
- pgoff = page_to_pgoff(page);
- anon_vma_interval_tree_foreach(avc, &anon_vma->rb_root, pgoff, pgoff) {
+ pgoff_start = page_to_pgoff(page);
+ pgoff_end = pgoff_start + hpage_nr_pages(page) - 1;
+ anon_vma_interval_tree_foreach(avc, &anon_vma->rb_root,
+ pgoff_start, pgoff_end) {
struct vm_area_struct *vma = avc->vma;
unsigned long address = vma_address(page, vma);
if (rwc->invalid_vma && rwc->invalid_vma(vma, rwc->arg))
continue;
- ret = rwc->rmap_one(page, vma, address, rwc->arg);
- if (ret != SWAP_AGAIN)
+ if (!rwc->rmap_one(page, vma, address, rwc->arg))
break;
if (rwc->done && rwc->done(page))
break;
if (!locked)
anon_vma_unlock_read(anon_vma);
- return ret;
}
/*
* vm_flags for that VMA. That should be OK, because that vma shouldn't be
* LOCKED.
*/
-static int rmap_walk_file(struct page *page, struct rmap_walk_control *rwc,
+static void rmap_walk_file(struct page *page, struct rmap_walk_control *rwc,
bool locked)
{
struct address_space *mapping = page_mapping(page);
- pgoff_t pgoff;
+ pgoff_t pgoff_start, pgoff_end;
struct vm_area_struct *vma;
- int ret = SWAP_AGAIN;
/*
* The page lock not only makes sure that page->mapping cannot
VM_BUG_ON_PAGE(!PageLocked(page), page);
if (!mapping)
- return ret;
+ return;
- pgoff = page_to_pgoff(page);
+ pgoff_start = page_to_pgoff(page);
+ pgoff_end = pgoff_start + hpage_nr_pages(page) - 1;
if (!locked)
i_mmap_lock_read(mapping);
- vma_interval_tree_foreach(vma, &mapping->i_mmap, pgoff, pgoff) {
+ vma_interval_tree_foreach(vma, &mapping->i_mmap,
+ pgoff_start, pgoff_end) {
unsigned long address = vma_address(page, vma);
cond_resched();
if (rwc->invalid_vma && rwc->invalid_vma(vma, rwc->arg))
continue;
- ret = rwc->rmap_one(page, vma, address, rwc->arg);
- if (ret != SWAP_AGAIN)
+ if (!rwc->rmap_one(page, vma, address, rwc->arg))
goto done;
if (rwc->done && rwc->done(page))
goto done;
done:
if (!locked)
i_mmap_unlock_read(mapping);
- return ret;
}
-int rmap_walk(struct page *page, struct rmap_walk_control *rwc)
+void rmap_walk(struct page *page, struct rmap_walk_control *rwc)
{
if (unlikely(PageKsm(page)))
- return rmap_walk_ksm(page, rwc);
+ rmap_walk_ksm(page, rwc);
else if (PageAnon(page))
- return rmap_walk_anon(page, rwc, false);
+ rmap_walk_anon(page, rwc, false);
else
- return rmap_walk_file(page, rwc, false);
+ rmap_walk_file(page, rwc, false);
}
/* Like rmap_walk, but caller holds relevant rmap lock */
-int rmap_walk_locked(struct page *page, struct rmap_walk_control *rwc)
+void rmap_walk_locked(struct page *page, struct rmap_walk_control *rwc)
{
/* no ksm support for now */
VM_BUG_ON_PAGE(PageKsm(page), page);
if (PageAnon(page))
- return rmap_walk_anon(page, rwc, true);
+ rmap_walk_anon(page, rwc, true);
else
- return rmap_walk_file(page, rwc, true);
+ rmap_walk_file(page, rwc, true);
}
#ifdef CONFIG_HUGETLB_PAGE
projects / karo-tx-linux.git / blobdiff