X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=mm%2Frmap.c;h=ba4fe1007d1fe15030118ce26941cc00b49dbd85;hb=97bf2856c6014879bd04983a3e9dfcdac1e7fe85;hp=086cf436b55e16799e907c9eb98ea78d64c08b9d;hpb=8e8ece46a861c84343256819eaec77e608ff9217;p=linux-2.6.git diff --git a/mm/rmap.c b/mm/rmap.c index 086cf436b..ba4fe1007 100644 --- a/mm/rmap.c +++ b/mm/rmap.c @@ -20,29 +20,22 @@ /* * Lock ordering in mm: * - * inode->i_sem (while writing or truncating, not reading or faulting) - * inode->i_alloc_sem - * - * When a page fault occurs in writing from user to file, down_read - * of mmap_sem nests within i_sem; in sys_msync, i_sem nests within - * down_read of mmap_sem; i_sem and down_write of mmap_sem are never - * taken together; in truncation, i_sem is taken outermost. - * - * mm->mmap_sem - * page->flags PG_locked (lock_page) - * mapping->i_mmap_lock - * anon_vma->lock - * mm->page_table_lock - * zone->lru_lock (in mark_page_accessed) - * swap_list_lock (in swap_free etc's swap_info_get) - * mmlist_lock (in mmput, drain_mmlist and others) - * swap_device_lock (in swap_duplicate, swap_info_get) - * mapping->private_lock (in __set_page_dirty_buffers) - * inode_lock (in set_page_dirty's __mark_inode_dirty) - * sb_lock (within inode_lock in fs/fs-writeback.c) - * mapping->tree_lock (widely used, in set_page_dirty, - * in arch-dependent flush_dcache_mmap_lock, - * within inode_lock in __sync_single_inode) + * inode->i_mutex (while writing or truncating, not reading or faulting) + * inode->i_alloc_sem (vmtruncate_range) + * mm->mmap_sem + * page->flags PG_locked (lock_page) + * mapping->i_mmap_lock + * anon_vma->lock + * mm->page_table_lock or pte_lock + * zone->lru_lock (in mark_page_accessed, isolate_lru_page) + * swap_lock (in swap_duplicate, swap_info_get) + * mmlist_lock (in mmput, drain_mmlist and others) + * mapping->private_lock (in __set_page_dirty_buffers) + * inode_lock (in set_page_dirty's __mark_inode_dirty) + * sb_lock (within inode_lock in fs/fs-writeback.c) + * mapping->tree_lock (widely used, in set_page_dirty, + * in arch-dependent flush_dcache_mmap_lock, + * within inode_lock in __sync_single_inode) */ #include @@ -51,20 +44,19 @@ #include #include #include -#include #include #include +#include +#include #include #include -//#define RMAP_DEBUG /* can be enabled only for debugging */ - -kmem_cache_t *anon_vma_cachep; +struct kmem_cache *anon_vma_cachep; static inline void validate_anon_vma(struct vm_area_struct *find_vma) { -#ifdef RMAP_DEBUG +#ifdef CONFIG_DEBUG_VM struct anon_vma *anon_vma = find_vma->anon_vma; struct vm_area_struct *vma; unsigned int mapcount = 0; @@ -107,7 +99,7 @@ int anon_vma_prepare(struct vm_area_struct *vma) spin_lock(&mm->page_table_lock); if (likely(!vma->anon_vma)) { vma->anon_vma = anon_vma; - list_add(&vma->anon_vma_node, &anon_vma->head); + list_add_tail(&vma->anon_vma_node, &anon_vma->head); allocated = NULL; } spin_unlock(&mm->page_table_lock); @@ -131,7 +123,7 @@ void __anon_vma_link(struct vm_area_struct *vma) struct anon_vma *anon_vma = vma->anon_vma; if (anon_vma) { - list_add(&vma->anon_vma_node, &anon_vma->head); + list_add_tail(&vma->anon_vma_node, &anon_vma->head); validate_anon_vma(vma); } } @@ -142,7 +134,7 @@ void anon_vma_link(struct vm_area_struct *vma) if (anon_vma) { spin_lock(&anon_vma->lock); - list_add(&vma->anon_vma_node, &anon_vma->head); + list_add_tail(&vma->anon_vma_node, &anon_vma->head); validate_anon_vma(vma); spin_unlock(&anon_vma->lock); } @@ -168,7 +160,8 @@ void anon_vma_unlink(struct vm_area_struct *vma) anon_vma_free(anon_vma); } -static void anon_vma_ctor(void *data, kmem_cache_t *cachep, unsigned long flags) +static void anon_vma_ctor(void *data, struct kmem_cache *cachep, + unsigned long flags) { if ((flags & (SLAB_CTOR_VERIFY|SLAB_CTOR_CONSTRUCTOR)) == SLAB_CTOR_CONSTRUCTOR) { @@ -228,7 +221,7 @@ vma_address(struct page *page, struct vm_area_struct *vma) /* * At what user virtual address is page expected in vma? checking that the - * page matches the vma: currently only used by unuse_process, on anon pages. + * page matches the vma: currently only used on anon pages, by unuse_vma; */ unsigned long page_address_in_vma(struct page *page, struct vm_area_struct *vma) { @@ -237,7 +230,8 @@ unsigned long page_address_in_vma(struct page *page, struct vm_area_struct *vma) (void *)page->mapping - PAGE_MAPPING_ANON) return -EFAULT; } else if (page->mapping && !(vma->vm_flags & VM_NONLINEAR)) { - if (vma->vm_file->f_mapping != page->mapping) + if (!vma->vm_file || + vma->vm_file->f_mapping != page->mapping) return -EFAULT; } else return -EFAULT; @@ -245,64 +239,85 @@ unsigned long page_address_in_vma(struct page *page, struct vm_area_struct *vma) } /* - * Subfunctions of page_referenced: page_referenced_one called - * repeatedly from either page_referenced_anon or page_referenced_file. + * Check that @page is mapped at @address into @mm. + * + * On success returns with pte mapped and locked. */ -static int page_referenced_one(struct page *page, - struct vm_area_struct *vma, unsigned int *mapcount, int ignore_token) +pte_t *page_check_address(struct page *page, struct mm_struct *mm, + unsigned long address, spinlock_t **ptlp) { - struct mm_struct *mm = vma->vm_mm; - unsigned long address; pgd_t *pgd; pud_t *pud; pmd_t *pmd; pte_t *pte; - int referenced = 0; - - if (!mm->rss) - goto out; - address = vma_address(page, vma); - if (address == -EFAULT) - goto out; - - spin_lock(&mm->page_table_lock); + spinlock_t *ptl; pgd = pgd_offset(mm, address); if (!pgd_present(*pgd)) - goto out_unlock; + return NULL; pud = pud_offset(pgd, address); if (!pud_present(*pud)) - goto out_unlock; + return NULL; pmd = pmd_offset(pud, address); if (!pmd_present(*pmd)) - goto out_unlock; + return NULL; pte = pte_offset_map(pmd, address); - if (!pte_present(*pte)) - goto out_unmap; + /* Make a quick check before getting the lock */ + if (!pte_present(*pte)) { + pte_unmap(pte); + return NULL; + } - if (page_to_pfn(page) != pte_pfn(*pte)) - goto out_unmap; + ptl = pte_lockptr(mm, pmd); + 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; +} + +/* + * Subfunctions of page_referenced: page_referenced_one called + * repeatedly from either page_referenced_anon or page_referenced_file. + */ +static int page_referenced_one(struct page *page, + struct vm_area_struct *vma, unsigned int *mapcount) +{ + struct mm_struct *mm = vma->vm_mm; + unsigned long address; + pte_t *pte; + spinlock_t *ptl; + int referenced = 0; + + address = vma_address(page, vma); + if (address == -EFAULT) + goto out; + + pte = page_check_address(page, mm, address, &ptl); + if (!pte) + goto out; if (ptep_clear_flush_young(vma, address, pte)) referenced++; - if (mm != current->mm && !ignore_token && has_swap_token(mm)) + /* Pretend the page is referenced if the task has the + swap token and is in the middle of a page fault. */ + if (mm != current->mm && has_swap_token(mm) && + rwsem_is_locked(&mm->mmap_sem)) referenced++; (*mapcount)--; - -out_unmap: - pte_unmap(pte); -out_unlock: - spin_unlock(&mm->page_table_lock); + pte_unmap_unlock(pte, ptl); out: return referenced; } -static int page_referenced_anon(struct page *page, int ignore_token) +static int page_referenced_anon(struct page *page) { unsigned int mapcount; struct anon_vma *anon_vma; @@ -315,8 +330,7 @@ static int page_referenced_anon(struct page *page, int ignore_token) mapcount = page_mapcount(page); list_for_each_entry(vma, &anon_vma->head, anon_vma_node) { - referenced += page_referenced_one(page, vma, &mapcount, - ignore_token); + referenced += page_referenced_one(page, vma, &mapcount); if (!mapcount) break; } @@ -335,7 +349,7 @@ static int page_referenced_anon(struct page *page, int ignore_token) * * This function is only called from page_referenced for object-based pages. */ -static int page_referenced_file(struct page *page, int ignore_token) +static int page_referenced_file(struct page *page) { unsigned int mapcount; struct address_space *mapping = page->mapping; @@ -373,8 +387,7 @@ static int page_referenced_file(struct page *page, int ignore_token) referenced++; break; } - referenced += page_referenced_one(page, vma, &mapcount, - ignore_token); + referenced += page_referenced_one(page, vma, &mapcount); if (!mapcount) break; } @@ -391,13 +404,10 @@ static int page_referenced_file(struct page *page, int ignore_token) * Quick test_and_clear_referenced for all mappings to a page, * returns the number of ptes which referenced the page. */ -int page_referenced(struct page *page, int is_locked, int ignore_token) +int page_referenced(struct page *page, int is_locked) { int referenced = 0; - if (!swap_token_default_timeout) - ignore_token = 1; - if (page_test_and_clear_young(page)) referenced++; @@ -406,81 +416,179 @@ int page_referenced(struct page *page, int is_locked, int ignore_token) if (page_mapped(page) && page->mapping) { if (PageAnon(page)) - referenced += page_referenced_anon(page, ignore_token); + referenced += page_referenced_anon(page); else if (is_locked) - referenced += page_referenced_file(page, ignore_token); + referenced += page_referenced_file(page); else if (TestSetPageLocked(page)) referenced++; else { if (page->mapping) - referenced += page_referenced_file(page, - ignore_token); + referenced += page_referenced_file(page); unlock_page(page); } } return referenced; } +static int page_mkclean_one(struct page *page, struct vm_area_struct *vma) +{ + struct mm_struct *mm = vma->vm_mm; + unsigned long address; + pte_t *pte; + spinlock_t *ptl; + int ret = 0; + + address = vma_address(page, vma); + if (address == -EFAULT) + goto out; + + pte = page_check_address(page, mm, address, &ptl); + if (!pte) + goto out; + + if (pte_dirty(*pte) || pte_write(*pte)) { + pte_t entry; + + 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); + lazy_mmu_prot_update(entry); + ret = 1; + } + + pte_unmap_unlock(pte, ptl); +out: + return ret; +} + +static int page_mkclean_file(struct address_space *mapping, struct page *page) +{ + pgoff_t pgoff = page->index << (PAGE_CACHE_SHIFT - PAGE_SHIFT); + struct vm_area_struct *vma; + struct prio_tree_iter iter; + int ret = 0; + + BUG_ON(PageAnon(page)); + + spin_lock(&mapping->i_mmap_lock); + vma_prio_tree_foreach(vma, &iter, &mapping->i_mmap, pgoff, pgoff) { + if (vma->vm_flags & VM_SHARED) + ret += page_mkclean_one(page, vma); + } + spin_unlock(&mapping->i_mmap_lock); + return ret; +} + +int page_mkclean(struct page *page) +{ + int ret = 0; + + BUG_ON(!PageLocked(page)); + + if (page_mapped(page)) { + struct address_space *mapping = page_mapping(page); + if (mapping) + ret = page_mkclean_file(mapping, page); + } + if (page_test_and_clear_dirty(page)) + ret = 1; + + return ret; +} + /** - * page_add_anon_rmap - add pte mapping to an anonymous page + * page_set_anon_rmap - setup new anonymous rmap * @page: the page to add the mapping to * @vma: the vm area in which the mapping is added * @address: the user virtual address mapped - * - * The caller needs to hold the mm->page_table_lock. */ -void page_add_anon_rmap(struct page *page, +static void __page_set_anon_rmap(struct page *page, struct vm_area_struct *vma, unsigned long address) { struct anon_vma *anon_vma = vma->anon_vma; - pgoff_t index; - BUG_ON(PageReserved(page)); BUG_ON(!anon_vma); + anon_vma = (void *) anon_vma + PAGE_MAPPING_ANON; + page->mapping = (struct address_space *) anon_vma; - vx_anonpages_inc(vma->vm_mm); + page->index = linear_page_index(vma, address); - anon_vma = (void *) anon_vma + PAGE_MAPPING_ANON; - index = (address - vma->vm_start) >> PAGE_SHIFT; - index += vma->vm_pgoff; - index >>= PAGE_CACHE_SHIFT - PAGE_SHIFT; - - if (atomic_inc_and_test(&page->_mapcount)) { - page->index = index; - page->mapping = (struct address_space *) anon_vma; - inc_page_state(nr_mapped); - } + /* + * nr_mapped state can be updated without turning off + * interrupts because it is not modified via interrupt. + */ + __inc_zone_page_state(page, NR_ANON_PAGES); +} + +/** + * page_add_anon_rmap - add pte mapping to an anonymous page + * @page: the page to add the mapping to + * @vma: the vm area in which the mapping is added + * @address: the user virtual address mapped + * + * The caller needs to hold the pte lock. + */ +void page_add_anon_rmap(struct page *page, + struct vm_area_struct *vma, unsigned long address) +{ + if (atomic_inc_and_test(&page->_mapcount)) + __page_set_anon_rmap(page, vma, address); /* else checking page index and mapping is racy */ } +/* + * page_add_new_anon_rmap - add pte mapping to a new anonymous page + * @page: the page to add the mapping to + * @vma: the vm area in which the mapping is added + * @address: the user virtual address mapped + * + * Same as page_add_anon_rmap but must only be called on *new* pages. + * This means the inc-and-test can be bypassed. + */ +void page_add_new_anon_rmap(struct page *page, + struct vm_area_struct *vma, unsigned long address) +{ + atomic_set(&page->_mapcount, 0); /* elevate count by 1 (starts at -1) */ + __page_set_anon_rmap(page, vma, address); +} + /** * page_add_file_rmap - add pte mapping to a file page * @page: the page to add the mapping to * - * The caller needs to hold the mm->page_table_lock. + * The caller needs to hold the pte lock. */ void page_add_file_rmap(struct page *page) { - BUG_ON(PageAnon(page)); - if (!pfn_valid(page_to_pfn(page)) || PageReserved(page)) - return; - if (atomic_inc_and_test(&page->_mapcount)) - inc_page_state(nr_mapped); + __inc_zone_page_state(page, NR_FILE_MAPPED); } /** * page_remove_rmap - take down pte mapping from a page * @page: page to remove mapping from * - * Caller needs to hold the mm->page_table_lock. + * The caller needs to hold the pte lock. */ -void page_remove_rmap(struct page *page) +void page_remove_rmap(struct page *page, struct vm_area_struct *vma) { - BUG_ON(PageReserved(page)); - if (atomic_add_negative(-1, &page->_mapcount)) { - BUG_ON(page_mapcount(page) < 0); + if (unlikely(page_mapcount(page) < 0)) { + printk (KERN_EMERG "Eeek! page_mapcount(page) went negative! (%d)\n", page_mapcount(page)); + printk (KERN_EMERG " page pfn = %lx\n", page_to_pfn(page)); + printk (KERN_EMERG " page->flags = %lx\n", page->flags); + printk (KERN_EMERG " page->count = %x\n", page_count(page)); + printk (KERN_EMERG " page->mapping = %p\n", page->mapping); + print_symbol (KERN_EMERG " vma->vm_ops = %s\n", (unsigned long)vma->vm_ops); + if (vma->vm_ops) + print_symbol (KERN_EMERG " vma->vm_ops->nopage = %s\n", (unsigned long)vma->vm_ops->nopage); + if (vma->vm_file && vma->vm_file->f_op) + print_symbol (KERN_EMERG " vma->vm_file->f_op->mmap = %s\n", (unsigned long)vma->vm_file->f_op->mmap); + BUG(); + } + /* * It would be tidy to reset the PageAnon mapping here, * but that might overwrite a racing page_add_anon_rmap @@ -492,7 +600,8 @@ void page_remove_rmap(struct page *page) */ if (page_test_and_clear_dirty(page)) set_page_dirty(page); - dec_page_state(nr_mapped); + __dec_zone_page_state(page, + PageAnon(page) ? NR_ANON_PAGES : NR_FILE_MAPPED); } } @@ -500,115 +609,92 @@ void page_remove_rmap(struct page *page) * Subfunctions of try_to_unmap: try_to_unmap_one called * repeatedly from either try_to_unmap_anon or try_to_unmap_file. */ -static int try_to_unmap_one(struct page *page, struct vm_area_struct *vma) +static int try_to_unmap_one(struct page *page, struct vm_area_struct *vma, + int migration) { struct mm_struct *mm = vma->vm_mm; unsigned long address; - pgd_t *pgd; - pud_t *pud; - pmd_t *pmd; pte_t *pte; pte_t pteval; + spinlock_t *ptl; int ret = SWAP_AGAIN; - if (!mm->rss) - goto out; address = vma_address(page, vma); if (address == -EFAULT) goto out; - /* - * We need the page_table_lock to protect us from page faults, - * munmap, fork, etc... - */ - spin_lock(&mm->page_table_lock); - - pgd = pgd_offset(mm, address); - if (!pgd_present(*pgd)) - goto out_unlock; - - pud = pud_offset(pgd, address); - if (!pud_present(*pud)) - goto out_unlock; - - pmd = pmd_offset(pud, address); - if (!pmd_present(*pmd)) - goto out_unlock; - - pte = pte_offset_map(pmd, address); - if (!pte_present(*pte)) - goto out_unmap; - - if (page_to_pfn(page) != pte_pfn(*pte)) - goto out_unmap; + pte = page_check_address(page, mm, address, &ptl); + 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 ((vma->vm_flags & (VM_LOCKED|VM_RESERVED)) || - ptep_clear_flush_young(vma, address, pte)) { - ret = SWAP_FAIL; - goto out_unmap; - } - - /* - * Don't pull an anonymous page out from under get_user_pages. - * GUP carefully breaks COW and raises page count (while holding - * page_table_lock, as we have here) to make sure that the page - * cannot be freed. If we unmap that page here, a user write - * access to the virtual address will bring back the page, but - * its raised count will (ironically) be taken to mean it's not - * an exclusive swap page, do_wp_page will replace it by a copy - * page, and the user never get to see the data GUP was holding - * the original page for. - * - * This test is also useful for when swapoff (unuse_process) has - * to drop page lock: its reference to the page stops existing - * ptes from being unmapped, so swapoff can make progress. - */ - if (PageSwapCache(page) && - page_count(page) != page_mapcount(page) + 2) { + if (!migration && ((vma->vm_flags & VM_LOCKED) || + (ptep_clear_flush_young(vma, address, pte)))) { ret = SWAP_FAIL; goto out_unmap; } /* Nuke the page table entry. */ - flush_cache_page(vma, address); + flush_cache_page(vma, address, page_to_pfn(page)); 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); + /* Update high watermark before we lower rss */ + update_hiwater_rss(mm); + if (PageAnon(page)) { - swp_entry_t entry = { .val = page->private }; - /* - * Store the swap location in the pte. - * See handle_pte_fault() ... - */ - BUG_ON(!PageSwapCache(page)); - swap_duplicate(entry); - if (list_empty(&mm->mmlist)) { - spin_lock(&mmlist_lock); - list_add(&mm->mmlist, &init_mm.mmlist); - spin_unlock(&mmlist_lock); + swp_entry_t entry = { .val = page_private(page) }; + + if (PageSwapCache(page)) { + /* + * Store the swap location in the pte. + * See handle_pte_fault() ... + */ + swap_duplicate(entry); + 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, anon_rss); +#ifdef CONFIG_MIGRATION + } else { + /* + * 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. + */ + BUG_ON(!migration); + entry = make_migration_entry(page, pte_write(pteval)); +#endif } - set_pte(pte, swp_entry_to_pte(entry)); + set_pte_at(mm, address, pte, swp_entry_to_pte(entry)); BUG_ON(pte_file(*pte)); - vx_anonpages_dec(mm); - } + } else +#ifdef CONFIG_MIGRATION + if (migration) { + /* Establish migration entry for a file page */ + swp_entry_t entry; + entry = make_migration_entry(page, pte_write(pteval)); + set_pte_at(mm, address, pte, swp_entry_to_pte(entry)); + } else +#endif + dec_mm_counter(mm, file_rss); - vx_rsspages_dec(mm); - acct_update_integrals(); - page_remove_rmap(page); + + page_remove_rmap(page, vma); page_cache_release(page); out_unmap: - pte_unmap(pte); -out_unlock: - spin_unlock(&mm->page_table_lock); + pte_unmap_unlock(pte, ptl); out: return ret; } @@ -644,16 +730,10 @@ static void try_to_unmap_cluster(unsigned long cursor, pmd_t *pmd; pte_t *pte; pte_t pteval; + spinlock_t *ptl; struct page *page; unsigned long address; unsigned long end; - unsigned long pfn; - - /* - * We need the page_table_lock to protect us from page faults, - * munmap, fork, etc... - */ - spin_lock(&mm->page_table_lock); address = (vma->vm_start + cursor) & CLUSTER_MASK; end = address + CLUSTER_SIZE; @@ -664,60 +744,51 @@ static void try_to_unmap_cluster(unsigned long cursor, pgd = pgd_offset(mm, address); if (!pgd_present(*pgd)) - goto out_unlock; + return; pud = pud_offset(pgd, address); if (!pud_present(*pud)) - goto out_unlock; + return; pmd = pmd_offset(pud, address); if (!pmd_present(*pmd)) - goto out_unlock; + return; - for (pte = pte_offset_map(pmd, address); - address < end; pte++, address += PAGE_SIZE) { + pte = pte_offset_map_lock(mm, pmd, address, &ptl); - if (!pte_present(*pte)) - continue; - - pfn = pte_pfn(*pte); - if (!pfn_valid(pfn)) - continue; + /* Update high watermark before we lower rss */ + update_hiwater_rss(mm); - page = pfn_to_page(pfn); - BUG_ON(PageAnon(page)); - if (PageReserved(page)) + for (; address < end; pte++, address += PAGE_SIZE) { + if (!pte_present(*pte)) continue; + page = vm_normal_page(vma, address, *pte); + BUG_ON(!page || PageAnon(page)); if (ptep_clear_flush_young(vma, address, pte)) continue; /* Nuke the page table entry. */ - flush_cache_page(vma, address); + flush_cache_page(vma, address, pte_pfn(*pte)); pteval = ptep_clear_flush(vma, address, pte); /* If nonlinear, store the file page offset in the pte. */ if (page->index != linear_page_index(vma, address)) - set_pte(pte, pgoff_to_pte(page->index)); + set_pte_at(mm, address, pte, pgoff_to_pte(page->index)); /* Move the dirty bit to the physical page now the pte is gone. */ if (pte_dirty(pteval)) set_page_dirty(page); - page_remove_rmap(page); + page_remove_rmap(page, vma); page_cache_release(page); - acct_update_integrals(); - vx_rsspages_dec(mm); + dec_mm_counter(mm, file_rss); (*mapcount)--; } - - pte_unmap(pte); - -out_unlock: - spin_unlock(&mm->page_table_lock); + pte_unmap_unlock(pte - 1, ptl); } -static int try_to_unmap_anon(struct page *page) +static int try_to_unmap_anon(struct page *page, int migration) { struct anon_vma *anon_vma; struct vm_area_struct *vma; @@ -728,7 +799,7 @@ static int try_to_unmap_anon(struct page *page) return ret; list_for_each_entry(vma, &anon_vma->head, anon_vma_node) { - ret = try_to_unmap_one(page, vma); + ret = try_to_unmap_one(page, vma, migration); if (ret == SWAP_FAIL || !page_mapped(page)) break; } @@ -745,7 +816,7 @@ static int try_to_unmap_anon(struct page *page) * * This function is only called from try_to_unmap for object-based pages. */ -static int try_to_unmap_file(struct page *page) +static int try_to_unmap_file(struct page *page, int migration) { struct address_space *mapping = page->mapping; pgoff_t pgoff = page->index << (PAGE_CACHE_SHIFT - PAGE_SHIFT); @@ -759,7 +830,7 @@ static int try_to_unmap_file(struct page *page) spin_lock(&mapping->i_mmap_lock); vma_prio_tree_foreach(vma, &iter, &mapping->i_mmap, pgoff, pgoff) { - ret = try_to_unmap_one(page, vma); + ret = try_to_unmap_one(page, vma, migration); if (ret == SWAP_FAIL || !page_mapped(page)) goto out; } @@ -769,7 +840,7 @@ static int try_to_unmap_file(struct page *page) list_for_each_entry(vma, &mapping->i_mmap_nonlinear, shared.vm_set.list) { - if (vma->vm_flags & (VM_LOCKED|VM_RESERVED)) + if ((vma->vm_flags & VM_LOCKED) && !migration) continue; cursor = (unsigned long) vma->vm_private_data; if (cursor > max_nl_cursor) @@ -803,11 +874,10 @@ static int try_to_unmap_file(struct page *page) do { list_for_each_entry(vma, &mapping->i_mmap_nonlinear, shared.vm_set.list) { - if (vma->vm_flags & (VM_LOCKED|VM_RESERVED)) + if ((vma->vm_flags & VM_LOCKED) && !migration) continue; cursor = (unsigned long) vma->vm_private_data; - while (vma->vm_mm->rss && - cursor < max_nl_cursor && + while ( cursor < max_nl_cursor && cursor < vma->vm_end - vma->vm_start) { try_to_unmap_cluster(cursor, &mapcount, vma); cursor += CLUSTER_SIZE; @@ -826,11 +896,8 @@ static int try_to_unmap_file(struct page *page) * in locked vmas). Reset cursor on all unreserved nonlinear * vmas, now forgetting on which ones it had fallen behind. */ - list_for_each_entry(vma, &mapping->i_mmap_nonlinear, - shared.vm_set.list) { - if (!(vma->vm_flags & VM_RESERVED)) - vma->vm_private_data = NULL; - } + list_for_each_entry(vma, &mapping->i_mmap_nonlinear, shared.vm_set.list) + vma->vm_private_data = NULL; out: spin_unlock(&mapping->i_mmap_lock); return ret; @@ -848,19 +915,19 @@ out: * SWAP_AGAIN - we missed a mapping, try again later * SWAP_FAIL - the page is unswappable */ -int try_to_unmap(struct page *page) +int try_to_unmap(struct page *page, int migration) { int ret; - BUG_ON(PageReserved(page)); BUG_ON(!PageLocked(page)); if (PageAnon(page)) - ret = try_to_unmap_anon(page); + ret = try_to_unmap_anon(page, migration); else - ret = try_to_unmap_file(page); + ret = try_to_unmap_file(page, migration); if (!page_mapped(page)) ret = SWAP_SUCCESS; return ret; } +