diff --git a/include/linux/rmap.h b/include/linux/rmap.h index 8dff2ffab82c..4c4a2d4d289e 100644 --- a/include/linux/rmap.h +++ b/include/linux/rmap.h @@ -85,7 +85,18 @@ static inline void page_dup_rmap(struct page *page, struct vm_area_struct *vma, */ int page_referenced(struct page *, int is_locked, struct mem_cgroup *cnt, unsigned long *vm_flags); -int try_to_unmap(struct page *, int ignore_refs); +enum ttu_flags { + TTU_UNMAP = 0, /* unmap mode */ + TTU_MIGRATION = 1, /* migration mode */ + TTU_MUNLOCK = 2, /* munlock mode */ + TTU_ACTION_MASK = 0xff, + + TTU_IGNORE_MLOCK = (1 << 8), /* ignore mlock */ + TTU_IGNORE_ACCESS = (1 << 9), /* don't age */ +}; +#define TTU_ACTION(x) ((x) & TTU_ACTION_MASK) + +int try_to_unmap(struct page *, enum ttu_flags flags); /* * Called from mm/filemap_xip.c to unmap empty zero page diff --git a/mm/migrate.c b/mm/migrate.c index 939888f9ddab..e3a0cd3859a9 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -669,7 +669,7 @@ static int unmap_and_move(new_page_t get_new_page, unsigned long private, } /* Establish migration ptes or remove ptes */ - try_to_unmap(page, 1); + try_to_unmap(page, TTU_MIGRATION|TTU_IGNORE_MLOCK|TTU_IGNORE_ACCESS); if (!page_mapped(page)) rc = move_to_new_page(newpage, page); diff --git a/mm/rmap.c b/mm/rmap.c index 5a35c030e779..08c112a776a7 100644 --- a/mm/rmap.c +++ b/mm/rmap.c @@ -774,7 +774,7 @@ void page_remove_rmap(struct page *page) * 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, - int migration) + enum ttu_flags flags) { struct mm_struct *mm = vma->vm_mm; unsigned long address; @@ -796,11 +796,13 @@ static int try_to_unmap_one(struct page *page, struct vm_area_struct *vma, * If it's recently referenced (perhaps page_referenced * skipped over this mm) then we should reactivate it. */ - if (!migration) { + if (!(flags & TTU_IGNORE_MLOCK)) { if (vma->vm_flags & VM_LOCKED) { ret = SWAP_MLOCK; goto out_unmap; } + } + if (!(flags & TTU_IGNORE_ACCESS)) { if (ptep_clear_flush_young_notify(vma, address, pte)) { ret = SWAP_FAIL; goto out_unmap; @@ -840,12 +842,12 @@ static int try_to_unmap_one(struct page *page, struct vm_area_struct *vma, * pte. do_swap_page() will wait until the migration * pte is removed and then restart fault handling. */ - BUG_ON(!migration); + BUG_ON(TTU_ACTION(flags) != TTU_MIGRATION); entry = make_migration_entry(page, pte_write(pteval)); } set_pte_at(mm, address, pte, swp_entry_to_pte(entry)); BUG_ON(pte_file(*pte)); - } else if (PAGE_MIGRATION && migration) { + } else if (PAGE_MIGRATION && (TTU_ACTION(flags) == TTU_MIGRATION)) { /* Establish migration entry for a file page */ swp_entry_t entry; entry = make_migration_entry(page, pte_write(pteval)); @@ -1014,12 +1016,13 @@ static int try_to_mlock_page(struct page *page, struct vm_area_struct *vma) * vm_flags for that VMA. That should be OK, because that vma shouldn't be * 'LOCKED. */ -static int try_to_unmap_anon(struct page *page, int unlock, int migration) +static int try_to_unmap_anon(struct page *page, enum ttu_flags flags) { struct anon_vma *anon_vma; struct vm_area_struct *vma; unsigned int mlocked = 0; int ret = SWAP_AGAIN; + int unlock = TTU_ACTION(flags) == TTU_MUNLOCK; if (MLOCK_PAGES && unlikely(unlock)) ret = SWAP_SUCCESS; /* default for try_to_munlock() */ @@ -1035,7 +1038,7 @@ static int try_to_unmap_anon(struct page *page, int unlock, int migration) continue; /* must visit all unlocked vmas */ ret = SWAP_MLOCK; /* saw at least one mlocked vma */ } else { - ret = try_to_unmap_one(page, vma, migration); + ret = try_to_unmap_one(page, vma, flags); if (ret == SWAP_FAIL || !page_mapped(page)) break; } @@ -1059,8 +1062,7 @@ static int try_to_unmap_anon(struct page *page, int unlock, int migration) /** * try_to_unmap_file - unmap/unlock file page using the object-based rmap method * @page: the page to unmap/unlock - * @unlock: request for unlock rather than unmap [unlikely] - * @migration: unmapping for migration - ignored if @unlock + * @flags: action and flags * * Find all the mappings of a page using the mapping pointer and the vma chains * contained in the address_space struct it points to. @@ -1072,7 +1074,7 @@ static int try_to_unmap_anon(struct page *page, int unlock, int migration) * vm_flags for that VMA. That should be OK, because that vma shouldn't be * 'LOCKED. */ -static int try_to_unmap_file(struct page *page, int unlock, int migration) +static int try_to_unmap_file(struct page *page, enum ttu_flags flags) { struct address_space *mapping = page->mapping; pgoff_t pgoff = page->index << (PAGE_CACHE_SHIFT - PAGE_SHIFT); @@ -1084,6 +1086,7 @@ static int try_to_unmap_file(struct page *page, int unlock, int migration) unsigned long max_nl_size = 0; unsigned int mapcount; unsigned int mlocked = 0; + int unlock = TTU_ACTION(flags) == TTU_MUNLOCK; if (MLOCK_PAGES && unlikely(unlock)) ret = SWAP_SUCCESS; /* default for try_to_munlock() */ @@ -1096,7 +1099,7 @@ static int try_to_unmap_file(struct page *page, int unlock, int migration) continue; /* must visit all vmas */ ret = SWAP_MLOCK; } else { - ret = try_to_unmap_one(page, vma, migration); + ret = try_to_unmap_one(page, vma, flags); if (ret == SWAP_FAIL || !page_mapped(page)) goto out; } @@ -1121,7 +1124,8 @@ static int try_to_unmap_file(struct page *page, int unlock, int migration) ret = SWAP_MLOCK; /* leave mlocked == 0 */ goto out; /* no need to look further */ } - if (!MLOCK_PAGES && !migration && (vma->vm_flags & VM_LOCKED)) + if (!MLOCK_PAGES && !(flags & TTU_IGNORE_MLOCK) && + (vma->vm_flags & VM_LOCKED)) continue; cursor = (unsigned long) vma->vm_private_data; if (cursor > max_nl_cursor) @@ -1155,7 +1159,7 @@ static int try_to_unmap_file(struct page *page, int unlock, int migration) do { list_for_each_entry(vma, &mapping->i_mmap_nonlinear, shared.vm_set.list) { - if (!MLOCK_PAGES && !migration && + if (!MLOCK_PAGES && !(flags & TTU_IGNORE_MLOCK) && (vma->vm_flags & VM_LOCKED)) continue; cursor = (unsigned long) vma->vm_private_data; @@ -1195,7 +1199,7 @@ out: /** * try_to_unmap - try to remove all page table mappings to a page * @page: the page to get unmapped - * @migration: migration flag + * @flags: action and flags * * Tries to remove all the page table entries which are mapping this * page, used in the pageout path. Caller must hold the page lock. @@ -1206,16 +1210,16 @@ out: * SWAP_FAIL - the page is unswappable * SWAP_MLOCK - page is mlocked. */ -int try_to_unmap(struct page *page, int migration) +int try_to_unmap(struct page *page, enum ttu_flags flags) { int ret; BUG_ON(!PageLocked(page)); if (PageAnon(page)) - ret = try_to_unmap_anon(page, 0, migration); + ret = try_to_unmap_anon(page, flags); else - ret = try_to_unmap_file(page, 0, migration); + ret = try_to_unmap_file(page, flags); if (ret != SWAP_MLOCK && !page_mapped(page)) ret = SWAP_SUCCESS; return ret; @@ -1240,8 +1244,8 @@ int try_to_munlock(struct page *page) VM_BUG_ON(!PageLocked(page) || PageLRU(page)); if (PageAnon(page)) - return try_to_unmap_anon(page, 1, 0); + return try_to_unmap_anon(page, TTU_MUNLOCK); else - return try_to_unmap_file(page, 1, 0); + return try_to_unmap_file(page, TTU_MUNLOCK); } diff --git a/mm/vmscan.c b/mm/vmscan.c index ba8228e0a806..ab3b0ad3ce52 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -659,7 +659,7 @@ static unsigned long shrink_page_list(struct list_head *page_list, * processes. Try to unmap it here. */ if (page_mapped(page) && mapping) { - switch (try_to_unmap(page, 0)) { + switch (try_to_unmap(page, TTU_UNMAP)) { case SWAP_FAIL: goto activate_locked; case SWAP_AGAIN: