11da177e4SLinus Torvalds /* 21da177e4SLinus Torvalds * mm/truncate.c - code for taking down pages from address_spaces 31da177e4SLinus Torvalds * 41da177e4SLinus Torvalds * Copyright (C) 2002, Linus Torvalds 51da177e4SLinus Torvalds * 6e1f8e874SFrancois Cami * 10Sep2002 Andrew Morton 71da177e4SLinus Torvalds * Initial version. 81da177e4SLinus Torvalds */ 91da177e4SLinus Torvalds 101da177e4SLinus Torvalds #include <linux/kernel.h> 114af3c9ccSAlexey Dobriyan #include <linux/backing-dev.h> 121da177e4SLinus Torvalds #include <linux/mm.h> 130fd0e6b0SNick Piggin #include <linux/swap.h> 141da177e4SLinus Torvalds #include <linux/module.h> 151da177e4SLinus Torvalds #include <linux/pagemap.h> 1601f2705dSNate Diller #include <linux/highmem.h> 171da177e4SLinus Torvalds #include <linux/pagevec.h> 18e08748ceSAndrew Morton #include <linux/task_io_accounting_ops.h> 191da177e4SLinus Torvalds #include <linux/buffer_head.h> /* grr. try_to_release_page, 20aaa4059bSJan Kara do_invalidatepage */ 21ba470de4SRik van Riel #include "internal.h" 221da177e4SLinus Torvalds 231da177e4SLinus Torvalds 24cf9a2ae8SDavid Howells /** 2528bc44d7SFengguang Wu * do_invalidatepage - invalidate part or all of a page 26cf9a2ae8SDavid Howells * @page: the page which is affected 27cf9a2ae8SDavid Howells * @offset: the index of the truncation point 28cf9a2ae8SDavid Howells * 29cf9a2ae8SDavid Howells * do_invalidatepage() is called when all or part of the page has become 30cf9a2ae8SDavid Howells * invalidated by a truncate operation. 31cf9a2ae8SDavid Howells * 32cf9a2ae8SDavid Howells * do_invalidatepage() does not have to release all buffers, but it must 33cf9a2ae8SDavid Howells * ensure that no dirty buffer is left outside @offset and that no I/O 34cf9a2ae8SDavid Howells * is underway against any of the blocks which are outside the truncation 35cf9a2ae8SDavid Howells * point. Because the caller is about to free (and possibly reuse) those 36cf9a2ae8SDavid Howells * blocks on-disk. 37cf9a2ae8SDavid Howells */ 38cf9a2ae8SDavid Howells void do_invalidatepage(struct page *page, unsigned long offset) 39cf9a2ae8SDavid Howells { 40cf9a2ae8SDavid Howells void (*invalidatepage)(struct page *, unsigned long); 41cf9a2ae8SDavid Howells invalidatepage = page->mapping->a_ops->invalidatepage; 429361401eSDavid Howells #ifdef CONFIG_BLOCK 43cf9a2ae8SDavid Howells if (!invalidatepage) 44cf9a2ae8SDavid Howells invalidatepage = block_invalidatepage; 459361401eSDavid Howells #endif 46cf9a2ae8SDavid Howells if (invalidatepage) 47cf9a2ae8SDavid Howells (*invalidatepage)(page, offset); 48cf9a2ae8SDavid Howells } 49cf9a2ae8SDavid Howells 501da177e4SLinus Torvalds static inline void truncate_partial_page(struct page *page, unsigned partial) 511da177e4SLinus Torvalds { 52eebd2aa3SChristoph Lameter zero_user_segment(page, partial, PAGE_CACHE_SIZE); 53266cf658SDavid Howells if (page_has_private(page)) 541da177e4SLinus Torvalds do_invalidatepage(page, partial); 551da177e4SLinus Torvalds } 561da177e4SLinus Torvalds 57ecdfc978SLinus Torvalds /* 58ecdfc978SLinus Torvalds * This cancels just the dirty bit on the kernel page itself, it 59ecdfc978SLinus Torvalds * does NOT actually remove dirty bits on any mmap's that may be 60ecdfc978SLinus Torvalds * around. It also leaves the page tagged dirty, so any sync 61ecdfc978SLinus Torvalds * activity will still find it on the dirty lists, and in particular, 62ecdfc978SLinus Torvalds * clear_page_dirty_for_io() will still look at the dirty bits in 63ecdfc978SLinus Torvalds * the VM. 64ecdfc978SLinus Torvalds * 65ecdfc978SLinus Torvalds * Doing this should *normally* only ever be done when a page 66ecdfc978SLinus Torvalds * is truncated, and is not actually mapped anywhere at all. However, 67ecdfc978SLinus Torvalds * fs/buffer.c does this when it notices that somebody has cleaned 68ecdfc978SLinus Torvalds * out all the buffers on a page without actually doing it through 69ecdfc978SLinus Torvalds * the VM. Can you say "ext3 is horribly ugly"? Tought you could. 70ecdfc978SLinus Torvalds */ 71fba2591bSLinus Torvalds void cancel_dirty_page(struct page *page, unsigned int account_size) 72fba2591bSLinus Torvalds { 738368e328SLinus Torvalds if (TestClearPageDirty(page)) { 748368e328SLinus Torvalds struct address_space *mapping = page->mapping; 758368e328SLinus Torvalds if (mapping && mapping_cap_account_dirty(mapping)) { 763e67c098SAndrew Morton dec_zone_page_state(page, NR_FILE_DIRTY); 77c9e51e41SPeter Zijlstra dec_bdi_stat(mapping->backing_dev_info, 78c9e51e41SPeter Zijlstra BDI_RECLAIMABLE); 798368e328SLinus Torvalds if (account_size) 80fba2591bSLinus Torvalds task_io_account_cancelled_write(account_size); 81fba2591bSLinus Torvalds } 823e67c098SAndrew Morton } 838368e328SLinus Torvalds } 848368e328SLinus Torvalds EXPORT_SYMBOL(cancel_dirty_page); 85fba2591bSLinus Torvalds 861da177e4SLinus Torvalds /* 871da177e4SLinus Torvalds * If truncate cannot remove the fs-private metadata from the page, the page 8862e1c553SShaohua Li * becomes orphaned. It will be left on the LRU and may even be mapped into 8954cb8821SNick Piggin * user pagetables if we're racing with filemap_fault(). 901da177e4SLinus Torvalds * 911da177e4SLinus Torvalds * We need to bale out if page->mapping is no longer equal to the original 921da177e4SLinus Torvalds * mapping. This happens a) when the VM reclaimed the page while we waited on 93fc0ecff6SAndrew Morton * its lock, b) when a concurrent invalidate_mapping_pages got there first and 941da177e4SLinus Torvalds * c) when tmpfs swizzles a page between a tmpfs inode and swapper_space. 951da177e4SLinus Torvalds */ 961da177e4SLinus Torvalds static void 971da177e4SLinus Torvalds truncate_complete_page(struct address_space *mapping, struct page *page) 981da177e4SLinus Torvalds { 991da177e4SLinus Torvalds if (page->mapping != mapping) 1001da177e4SLinus Torvalds return; 1011da177e4SLinus Torvalds 102266cf658SDavid Howells if (page_has_private(page)) 1031da177e4SLinus Torvalds do_invalidatepage(page, 0); 1041da177e4SLinus Torvalds 105a2b34564SBjorn Steinbrink cancel_dirty_page(page, PAGE_CACHE_SIZE); 106a2b34564SBjorn Steinbrink 107ba470de4SRik van Riel clear_page_mlock(page); 108787d2214SNick Piggin remove_from_page_cache(page); 1091da177e4SLinus Torvalds ClearPageMappedToDisk(page); 1101da177e4SLinus Torvalds page_cache_release(page); /* pagecache ref */ 1111da177e4SLinus Torvalds } 1121da177e4SLinus Torvalds 1131da177e4SLinus Torvalds /* 114fc0ecff6SAndrew Morton * This is for invalidate_mapping_pages(). That function can be called at 1151da177e4SLinus Torvalds * any time, and is not supposed to throw away dirty pages. But pages can 1160fd0e6b0SNick Piggin * be marked dirty at any time too, so use remove_mapping which safely 1170fd0e6b0SNick Piggin * discards clean, unused pages. 1181da177e4SLinus Torvalds * 1191da177e4SLinus Torvalds * Returns non-zero if the page was successfully invalidated. 1201da177e4SLinus Torvalds */ 1211da177e4SLinus Torvalds static int 1221da177e4SLinus Torvalds invalidate_complete_page(struct address_space *mapping, struct page *page) 1231da177e4SLinus Torvalds { 1240fd0e6b0SNick Piggin int ret; 1250fd0e6b0SNick Piggin 1261da177e4SLinus Torvalds if (page->mapping != mapping) 1271da177e4SLinus Torvalds return 0; 1281da177e4SLinus Torvalds 129266cf658SDavid Howells if (page_has_private(page) && !try_to_release_page(page, 0)) 1301da177e4SLinus Torvalds return 0; 1311da177e4SLinus Torvalds 132ba470de4SRik van Riel clear_page_mlock(page); 1330fd0e6b0SNick Piggin ret = remove_mapping(mapping, page); 1340fd0e6b0SNick Piggin 1350fd0e6b0SNick Piggin return ret; 1361da177e4SLinus Torvalds } 1371da177e4SLinus Torvalds 1381da177e4SLinus Torvalds /** 1390643245fSRandy Dunlap * truncate_inode_pages - truncate range of pages specified by start & end byte offsets 1401da177e4SLinus Torvalds * @mapping: mapping to truncate 1411da177e4SLinus Torvalds * @lstart: offset from which to truncate 142d7339071SHans Reiser * @lend: offset to which to truncate 1431da177e4SLinus Torvalds * 144d7339071SHans Reiser * Truncate the page cache, removing the pages that are between 145d7339071SHans Reiser * specified offsets (and zeroing out partial page 146d7339071SHans Reiser * (if lstart is not page aligned)). 1471da177e4SLinus Torvalds * 1481da177e4SLinus Torvalds * Truncate takes two passes - the first pass is nonblocking. It will not 1491da177e4SLinus Torvalds * block on page locks and it will not block on writeback. The second pass 1501da177e4SLinus Torvalds * will wait. This is to prevent as much IO as possible in the affected region. 1511da177e4SLinus Torvalds * The first pass will remove most pages, so the search cost of the second pass 1521da177e4SLinus Torvalds * is low. 1531da177e4SLinus Torvalds * 1541da177e4SLinus Torvalds * When looking at page->index outside the page lock we need to be careful to 1551da177e4SLinus Torvalds * copy it into a local to avoid races (it could change at any time). 1561da177e4SLinus Torvalds * 1571da177e4SLinus Torvalds * We pass down the cache-hot hint to the page freeing code. Even if the 1581da177e4SLinus Torvalds * mapping is large, it is probably the case that the final pages are the most 1591da177e4SLinus Torvalds * recently touched, and freeing happens in ascending file offset order. 1601da177e4SLinus Torvalds */ 161d7339071SHans Reiser void truncate_inode_pages_range(struct address_space *mapping, 162d7339071SHans Reiser loff_t lstart, loff_t lend) 1631da177e4SLinus Torvalds { 1641da177e4SLinus Torvalds const pgoff_t start = (lstart + PAGE_CACHE_SIZE-1) >> PAGE_CACHE_SHIFT; 165d7339071SHans Reiser pgoff_t end; 1661da177e4SLinus Torvalds const unsigned partial = lstart & (PAGE_CACHE_SIZE - 1); 1671da177e4SLinus Torvalds struct pagevec pvec; 1681da177e4SLinus Torvalds pgoff_t next; 1691da177e4SLinus Torvalds int i; 1701da177e4SLinus Torvalds 1711da177e4SLinus Torvalds if (mapping->nrpages == 0) 1721da177e4SLinus Torvalds return; 1731da177e4SLinus Torvalds 174d7339071SHans Reiser BUG_ON((lend & (PAGE_CACHE_SIZE - 1)) != (PAGE_CACHE_SIZE - 1)); 175d7339071SHans Reiser end = (lend >> PAGE_CACHE_SHIFT); 176d7339071SHans Reiser 1771da177e4SLinus Torvalds pagevec_init(&pvec, 0); 1781da177e4SLinus Torvalds next = start; 179d7339071SHans Reiser while (next <= end && 180d7339071SHans Reiser pagevec_lookup(&pvec, mapping, next, PAGEVEC_SIZE)) { 1811da177e4SLinus Torvalds for (i = 0; i < pagevec_count(&pvec); i++) { 1821da177e4SLinus Torvalds struct page *page = pvec.pages[i]; 1831da177e4SLinus Torvalds pgoff_t page_index = page->index; 1841da177e4SLinus Torvalds 185d7339071SHans Reiser if (page_index > end) { 186d7339071SHans Reiser next = page_index; 187d7339071SHans Reiser break; 188d7339071SHans Reiser } 189d7339071SHans Reiser 1901da177e4SLinus Torvalds if (page_index > next) 1911da177e4SLinus Torvalds next = page_index; 1921da177e4SLinus Torvalds next++; 193529ae9aaSNick Piggin if (!trylock_page(page)) 1941da177e4SLinus Torvalds continue; 1951da177e4SLinus Torvalds if (PageWriteback(page)) { 1961da177e4SLinus Torvalds unlock_page(page); 1971da177e4SLinus Torvalds continue; 1981da177e4SLinus Torvalds } 199d00806b1SNick Piggin if (page_mapped(page)) { 200d00806b1SNick Piggin unmap_mapping_range(mapping, 201d00806b1SNick Piggin (loff_t)page_index<<PAGE_CACHE_SHIFT, 202d00806b1SNick Piggin PAGE_CACHE_SIZE, 0); 203d00806b1SNick Piggin } 2041da177e4SLinus Torvalds truncate_complete_page(mapping, page); 2051da177e4SLinus Torvalds unlock_page(page); 2061da177e4SLinus Torvalds } 2071da177e4SLinus Torvalds pagevec_release(&pvec); 2081da177e4SLinus Torvalds cond_resched(); 2091da177e4SLinus Torvalds } 2101da177e4SLinus Torvalds 2111da177e4SLinus Torvalds if (partial) { 2121da177e4SLinus Torvalds struct page *page = find_lock_page(mapping, start - 1); 2131da177e4SLinus Torvalds if (page) { 2141da177e4SLinus Torvalds wait_on_page_writeback(page); 2151da177e4SLinus Torvalds truncate_partial_page(page, partial); 2161da177e4SLinus Torvalds unlock_page(page); 2171da177e4SLinus Torvalds page_cache_release(page); 2181da177e4SLinus Torvalds } 2191da177e4SLinus Torvalds } 2201da177e4SLinus Torvalds 2211da177e4SLinus Torvalds next = start; 2221da177e4SLinus Torvalds for ( ; ; ) { 2231da177e4SLinus Torvalds cond_resched(); 2241da177e4SLinus Torvalds if (!pagevec_lookup(&pvec, mapping, next, PAGEVEC_SIZE)) { 2251da177e4SLinus Torvalds if (next == start) 2261da177e4SLinus Torvalds break; 2271da177e4SLinus Torvalds next = start; 2281da177e4SLinus Torvalds continue; 2291da177e4SLinus Torvalds } 230d7339071SHans Reiser if (pvec.pages[0]->index > end) { 231d7339071SHans Reiser pagevec_release(&pvec); 232d7339071SHans Reiser break; 233d7339071SHans Reiser } 2341da177e4SLinus Torvalds for (i = 0; i < pagevec_count(&pvec); i++) { 2351da177e4SLinus Torvalds struct page *page = pvec.pages[i]; 2361da177e4SLinus Torvalds 237d7339071SHans Reiser if (page->index > end) 238d7339071SHans Reiser break; 2391da177e4SLinus Torvalds lock_page(page); 2401da177e4SLinus Torvalds wait_on_page_writeback(page); 241d00806b1SNick Piggin if (page_mapped(page)) { 242d00806b1SNick Piggin unmap_mapping_range(mapping, 243d00806b1SNick Piggin (loff_t)page->index<<PAGE_CACHE_SHIFT, 244d00806b1SNick Piggin PAGE_CACHE_SIZE, 0); 245d00806b1SNick Piggin } 2461da177e4SLinus Torvalds if (page->index > next) 2471da177e4SLinus Torvalds next = page->index; 2481da177e4SLinus Torvalds next++; 2491da177e4SLinus Torvalds truncate_complete_page(mapping, page); 2501da177e4SLinus Torvalds unlock_page(page); 2511da177e4SLinus Torvalds } 2521da177e4SLinus Torvalds pagevec_release(&pvec); 2531da177e4SLinus Torvalds } 2541da177e4SLinus Torvalds } 255d7339071SHans Reiser EXPORT_SYMBOL(truncate_inode_pages_range); 2561da177e4SLinus Torvalds 257d7339071SHans Reiser /** 258d7339071SHans Reiser * truncate_inode_pages - truncate *all* the pages from an offset 259d7339071SHans Reiser * @mapping: mapping to truncate 260d7339071SHans Reiser * @lstart: offset from which to truncate 261d7339071SHans Reiser * 2621b1dcc1bSJes Sorensen * Called under (and serialised by) inode->i_mutex. 263d7339071SHans Reiser */ 264d7339071SHans Reiser void truncate_inode_pages(struct address_space *mapping, loff_t lstart) 265d7339071SHans Reiser { 266d7339071SHans Reiser truncate_inode_pages_range(mapping, lstart, (loff_t)-1); 267d7339071SHans Reiser } 2681da177e4SLinus Torvalds EXPORT_SYMBOL(truncate_inode_pages); 2691da177e4SLinus Torvalds 270fc9a07e7SAndrew Morton unsigned long __invalidate_mapping_pages(struct address_space *mapping, 271fc9a07e7SAndrew Morton pgoff_t start, pgoff_t end, bool be_atomic) 2721da177e4SLinus Torvalds { 2731da177e4SLinus Torvalds struct pagevec pvec; 2741da177e4SLinus Torvalds pgoff_t next = start; 2751da177e4SLinus Torvalds unsigned long ret = 0; 2761da177e4SLinus Torvalds int i; 2771da177e4SLinus Torvalds 2781da177e4SLinus Torvalds pagevec_init(&pvec, 0); 2791da177e4SLinus Torvalds while (next <= end && 2801da177e4SLinus Torvalds pagevec_lookup(&pvec, mapping, next, PAGEVEC_SIZE)) { 2811da177e4SLinus Torvalds for (i = 0; i < pagevec_count(&pvec); i++) { 2821da177e4SLinus Torvalds struct page *page = pvec.pages[i]; 283e0f23603SNeilBrown pgoff_t index; 284e0f23603SNeilBrown int lock_failed; 2851da177e4SLinus Torvalds 286529ae9aaSNick Piggin lock_failed = !trylock_page(page); 287e0f23603SNeilBrown 288e0f23603SNeilBrown /* 289e0f23603SNeilBrown * We really shouldn't be looking at the ->index of an 290e0f23603SNeilBrown * unlocked page. But we're not allowed to lock these 291e0f23603SNeilBrown * pages. So we rely upon nobody altering the ->index 292e0f23603SNeilBrown * of this (pinned-by-us) page. 293e0f23603SNeilBrown */ 294e0f23603SNeilBrown index = page->index; 295e0f23603SNeilBrown if (index > next) 296e0f23603SNeilBrown next = index; 2971da177e4SLinus Torvalds next++; 298e0f23603SNeilBrown if (lock_failed) 2991da177e4SLinus Torvalds continue; 300e0f23603SNeilBrown 3011da177e4SLinus Torvalds if (PageDirty(page) || PageWriteback(page)) 3021da177e4SLinus Torvalds goto unlock; 3031da177e4SLinus Torvalds if (page_mapped(page)) 3041da177e4SLinus Torvalds goto unlock; 3051da177e4SLinus Torvalds ret += invalidate_complete_page(mapping, page); 3061da177e4SLinus Torvalds unlock: 3071da177e4SLinus Torvalds unlock_page(page); 3081da177e4SLinus Torvalds if (next > end) 3091da177e4SLinus Torvalds break; 3101da177e4SLinus Torvalds } 3111da177e4SLinus Torvalds pagevec_release(&pvec); 312fc9a07e7SAndrew Morton if (likely(!be_atomic)) 313fc9a07e7SAndrew Morton cond_resched(); 3141da177e4SLinus Torvalds } 3151da177e4SLinus Torvalds return ret; 3161da177e4SLinus Torvalds } 317fc9a07e7SAndrew Morton 318fc9a07e7SAndrew Morton /** 319fc9a07e7SAndrew Morton * invalidate_mapping_pages - Invalidate all the unlocked pages of one inode 320fc9a07e7SAndrew Morton * @mapping: the address_space which holds the pages to invalidate 321fc9a07e7SAndrew Morton * @start: the offset 'from' which to invalidate 322fc9a07e7SAndrew Morton * @end: the offset 'to' which to invalidate (inclusive) 323fc9a07e7SAndrew Morton * 324fc9a07e7SAndrew Morton * This function only removes the unlocked pages, if you want to 325fc9a07e7SAndrew Morton * remove all the pages of one inode, you must call truncate_inode_pages. 326fc9a07e7SAndrew Morton * 327fc9a07e7SAndrew Morton * invalidate_mapping_pages() will not block on IO activity. It will not 328fc9a07e7SAndrew Morton * invalidate pages which are dirty, locked, under writeback or mapped into 329fc9a07e7SAndrew Morton * pagetables. 330fc9a07e7SAndrew Morton */ 331fc9a07e7SAndrew Morton unsigned long invalidate_mapping_pages(struct address_space *mapping, 332fc9a07e7SAndrew Morton pgoff_t start, pgoff_t end) 333fc9a07e7SAndrew Morton { 334fc9a07e7SAndrew Morton return __invalidate_mapping_pages(mapping, start, end, false); 335fc9a07e7SAndrew Morton } 33654bc4855SAnton Altaparmakov EXPORT_SYMBOL(invalidate_mapping_pages); 3371da177e4SLinus Torvalds 338bd4c8ce4SAndrew Morton /* 339bd4c8ce4SAndrew Morton * This is like invalidate_complete_page(), except it ignores the page's 340bd4c8ce4SAndrew Morton * refcount. We do this because invalidate_inode_pages2() needs stronger 341bd4c8ce4SAndrew Morton * invalidation guarantees, and cannot afford to leave pages behind because 3422706a1b8SAnderson Briglia * shrink_page_list() has a temp ref on them, or because they're transiently 3432706a1b8SAnderson Briglia * sitting in the lru_cache_add() pagevecs. 344bd4c8ce4SAndrew Morton */ 345bd4c8ce4SAndrew Morton static int 346bd4c8ce4SAndrew Morton invalidate_complete_page2(struct address_space *mapping, struct page *page) 347bd4c8ce4SAndrew Morton { 348bd4c8ce4SAndrew Morton if (page->mapping != mapping) 349bd4c8ce4SAndrew Morton return 0; 350bd4c8ce4SAndrew Morton 351266cf658SDavid Howells if (page_has_private(page) && !try_to_release_page(page, GFP_KERNEL)) 352bd4c8ce4SAndrew Morton return 0; 353bd4c8ce4SAndrew Morton 35419fd6231SNick Piggin spin_lock_irq(&mapping->tree_lock); 355bd4c8ce4SAndrew Morton if (PageDirty(page)) 356bd4c8ce4SAndrew Morton goto failed; 357bd4c8ce4SAndrew Morton 358ba470de4SRik van Riel clear_page_mlock(page); 359266cf658SDavid Howells BUG_ON(page_has_private(page)); 360bd4c8ce4SAndrew Morton __remove_from_page_cache(page); 36119fd6231SNick Piggin spin_unlock_irq(&mapping->tree_lock); 362*e767e056SDaisuke Nishimura mem_cgroup_uncharge_cache_page(page); 363bd4c8ce4SAndrew Morton page_cache_release(page); /* pagecache ref */ 364bd4c8ce4SAndrew Morton return 1; 365bd4c8ce4SAndrew Morton failed: 36619fd6231SNick Piggin spin_unlock_irq(&mapping->tree_lock); 367bd4c8ce4SAndrew Morton return 0; 368bd4c8ce4SAndrew Morton } 369bd4c8ce4SAndrew Morton 370e3db7691STrond Myklebust static int do_launder_page(struct address_space *mapping, struct page *page) 371e3db7691STrond Myklebust { 372e3db7691STrond Myklebust if (!PageDirty(page)) 373e3db7691STrond Myklebust return 0; 374e3db7691STrond Myklebust if (page->mapping != mapping || mapping->a_ops->launder_page == NULL) 375e3db7691STrond Myklebust return 0; 376e3db7691STrond Myklebust return mapping->a_ops->launder_page(page); 377e3db7691STrond Myklebust } 378e3db7691STrond Myklebust 3791da177e4SLinus Torvalds /** 3801da177e4SLinus Torvalds * invalidate_inode_pages2_range - remove range of pages from an address_space 38167be2dd1SMartin Waitz * @mapping: the address_space 3821da177e4SLinus Torvalds * @start: the page offset 'from' which to invalidate 3831da177e4SLinus Torvalds * @end: the page offset 'to' which to invalidate (inclusive) 3841da177e4SLinus Torvalds * 3851da177e4SLinus Torvalds * Any pages which are found to be mapped into pagetables are unmapped prior to 3861da177e4SLinus Torvalds * invalidation. 3871da177e4SLinus Torvalds * 3886ccfa806SHisashi Hifumi * Returns -EBUSY if any pages could not be invalidated. 3891da177e4SLinus Torvalds */ 3901da177e4SLinus Torvalds int invalidate_inode_pages2_range(struct address_space *mapping, 3911da177e4SLinus Torvalds pgoff_t start, pgoff_t end) 3921da177e4SLinus Torvalds { 3931da177e4SLinus Torvalds struct pagevec pvec; 3941da177e4SLinus Torvalds pgoff_t next; 3951da177e4SLinus Torvalds int i; 3961da177e4SLinus Torvalds int ret = 0; 3970dd1334fSHisashi Hifumi int ret2 = 0; 3981da177e4SLinus Torvalds int did_range_unmap = 0; 3991da177e4SLinus Torvalds int wrapped = 0; 4001da177e4SLinus Torvalds 4011da177e4SLinus Torvalds pagevec_init(&pvec, 0); 4021da177e4SLinus Torvalds next = start; 4037b965e08STrond Myklebust while (next <= end && !wrapped && 4041da177e4SLinus Torvalds pagevec_lookup(&pvec, mapping, next, 4051da177e4SLinus Torvalds min(end - next, (pgoff_t)PAGEVEC_SIZE - 1) + 1)) { 4067b965e08STrond Myklebust for (i = 0; i < pagevec_count(&pvec); i++) { 4071da177e4SLinus Torvalds struct page *page = pvec.pages[i]; 4081da177e4SLinus Torvalds pgoff_t page_index; 4091da177e4SLinus Torvalds 4101da177e4SLinus Torvalds lock_page(page); 4111da177e4SLinus Torvalds if (page->mapping != mapping) { 4121da177e4SLinus Torvalds unlock_page(page); 4131da177e4SLinus Torvalds continue; 4141da177e4SLinus Torvalds } 4151da177e4SLinus Torvalds page_index = page->index; 4161da177e4SLinus Torvalds next = page_index + 1; 4171da177e4SLinus Torvalds if (next == 0) 4181da177e4SLinus Torvalds wrapped = 1; 4191da177e4SLinus Torvalds if (page_index > end) { 4201da177e4SLinus Torvalds unlock_page(page); 4211da177e4SLinus Torvalds break; 4221da177e4SLinus Torvalds } 4231da177e4SLinus Torvalds wait_on_page_writeback(page); 424d00806b1SNick Piggin if (page_mapped(page)) { 4251da177e4SLinus Torvalds if (!did_range_unmap) { 4261da177e4SLinus Torvalds /* 4271da177e4SLinus Torvalds * Zap the rest of the file in one hit. 4281da177e4SLinus Torvalds */ 4291da177e4SLinus Torvalds unmap_mapping_range(mapping, 430479ef592SOleg Drokin (loff_t)page_index<<PAGE_CACHE_SHIFT, 431479ef592SOleg Drokin (loff_t)(end - page_index + 1) 4321da177e4SLinus Torvalds << PAGE_CACHE_SHIFT, 4331da177e4SLinus Torvalds 0); 4341da177e4SLinus Torvalds did_range_unmap = 1; 4351da177e4SLinus Torvalds } else { 4361da177e4SLinus Torvalds /* 4371da177e4SLinus Torvalds * Just zap this page 4381da177e4SLinus Torvalds */ 4391da177e4SLinus Torvalds unmap_mapping_range(mapping, 440479ef592SOleg Drokin (loff_t)page_index<<PAGE_CACHE_SHIFT, 4411da177e4SLinus Torvalds PAGE_CACHE_SIZE, 0); 4421da177e4SLinus Torvalds } 4431da177e4SLinus Torvalds } 444d00806b1SNick Piggin BUG_ON(page_mapped(page)); 4450dd1334fSHisashi Hifumi ret2 = do_launder_page(mapping, page); 4460dd1334fSHisashi Hifumi if (ret2 == 0) { 4470dd1334fSHisashi Hifumi if (!invalidate_complete_page2(mapping, page)) 4486ccfa806SHisashi Hifumi ret2 = -EBUSY; 4490dd1334fSHisashi Hifumi } 4500dd1334fSHisashi Hifumi if (ret2 < 0) 4510dd1334fSHisashi Hifumi ret = ret2; 4521da177e4SLinus Torvalds unlock_page(page); 4531da177e4SLinus Torvalds } 4541da177e4SLinus Torvalds pagevec_release(&pvec); 4551da177e4SLinus Torvalds cond_resched(); 4561da177e4SLinus Torvalds } 4571da177e4SLinus Torvalds return ret; 4581da177e4SLinus Torvalds } 4591da177e4SLinus Torvalds EXPORT_SYMBOL_GPL(invalidate_inode_pages2_range); 4601da177e4SLinus Torvalds 4611da177e4SLinus Torvalds /** 4621da177e4SLinus Torvalds * invalidate_inode_pages2 - remove all pages from an address_space 46367be2dd1SMartin Waitz * @mapping: the address_space 4641da177e4SLinus Torvalds * 4651da177e4SLinus Torvalds * Any pages which are found to be mapped into pagetables are unmapped prior to 4661da177e4SLinus Torvalds * invalidation. 4671da177e4SLinus Torvalds * 4681da177e4SLinus Torvalds * Returns -EIO if any pages could not be invalidated. 4691da177e4SLinus Torvalds */ 4701da177e4SLinus Torvalds int invalidate_inode_pages2(struct address_space *mapping) 4711da177e4SLinus Torvalds { 4721da177e4SLinus Torvalds return invalidate_inode_pages2_range(mapping, 0, -1); 4731da177e4SLinus Torvalds } 4741da177e4SLinus Torvalds EXPORT_SYMBOL_GPL(invalidate_inode_pages2); 475