Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * mm/truncate.c - code for taking down pages from address_spaces |
| 3 | * |
| 4 | * Copyright (C) 2002, Linus Torvalds |
| 5 | * |
| 6 | * 10Sep2002 akpm@zip.com.au |
| 7 | * Initial version. |
| 8 | */ |
| 9 | |
| 10 | #include <linux/kernel.h> |
Alexey Dobriyan | 4af3c9c | 2007-10-16 23:29:23 -0700 | [diff] [blame] | 11 | #include <linux/backing-dev.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 12 | #include <linux/mm.h> |
Nick Piggin | 0fd0e6b | 2006-09-27 01:50:02 -0700 | [diff] [blame] | 13 | #include <linux/swap.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 14 | #include <linux/module.h> |
| 15 | #include <linux/pagemap.h> |
Nate Diller | 01f2705 | 2007-05-09 02:35:07 -0700 | [diff] [blame] | 16 | #include <linux/highmem.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 17 | #include <linux/pagevec.h> |
Andrew Morton | e08748c | 2006-12-10 02:19:31 -0800 | [diff] [blame] | 18 | #include <linux/task_io_accounting_ops.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 19 | #include <linux/buffer_head.h> /* grr. try_to_release_page, |
Jan Kara | aaa4059 | 2005-10-30 15:00:16 -0800 | [diff] [blame] | 20 | do_invalidatepage */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 21 | |
| 22 | |
David Howells | cf9a2ae | 2006-08-29 19:05:54 +0100 | [diff] [blame] | 23 | /** |
Fengguang Wu | 28bc44d | 2008-02-03 18:04:10 +0200 | [diff] [blame] | 24 | * do_invalidatepage - invalidate part or all of a page |
David Howells | cf9a2ae | 2006-08-29 19:05:54 +0100 | [diff] [blame] | 25 | * @page: the page which is affected |
| 26 | * @offset: the index of the truncation point |
| 27 | * |
| 28 | * do_invalidatepage() is called when all or part of the page has become |
| 29 | * invalidated by a truncate operation. |
| 30 | * |
| 31 | * do_invalidatepage() does not have to release all buffers, but it must |
| 32 | * ensure that no dirty buffer is left outside @offset and that no I/O |
| 33 | * is underway against any of the blocks which are outside the truncation |
| 34 | * point. Because the caller is about to free (and possibly reuse) those |
| 35 | * blocks on-disk. |
| 36 | */ |
| 37 | void do_invalidatepage(struct page *page, unsigned long offset) |
| 38 | { |
| 39 | void (*invalidatepage)(struct page *, unsigned long); |
| 40 | invalidatepage = page->mapping->a_ops->invalidatepage; |
David Howells | 9361401 | 2006-09-30 20:45:40 +0200 | [diff] [blame] | 41 | #ifdef CONFIG_BLOCK |
David Howells | cf9a2ae | 2006-08-29 19:05:54 +0100 | [diff] [blame] | 42 | if (!invalidatepage) |
| 43 | invalidatepage = block_invalidatepage; |
David Howells | 9361401 | 2006-09-30 20:45:40 +0200 | [diff] [blame] | 44 | #endif |
David Howells | cf9a2ae | 2006-08-29 19:05:54 +0100 | [diff] [blame] | 45 | if (invalidatepage) |
| 46 | (*invalidatepage)(page, offset); |
| 47 | } |
| 48 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 49 | static inline void truncate_partial_page(struct page *page, unsigned partial) |
| 50 | { |
Nate Diller | 01f2705 | 2007-05-09 02:35:07 -0700 | [diff] [blame] | 51 | zero_user_page(page, partial, PAGE_CACHE_SIZE - partial, KM_USER0); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 52 | if (PagePrivate(page)) |
| 53 | do_invalidatepage(page, partial); |
| 54 | } |
| 55 | |
Linus Torvalds | ecdfc97 | 2007-01-26 12:47:06 -0800 | [diff] [blame] | 56 | /* |
| 57 | * This cancels just the dirty bit on the kernel page itself, it |
| 58 | * does NOT actually remove dirty bits on any mmap's that may be |
| 59 | * around. It also leaves the page tagged dirty, so any sync |
| 60 | * activity will still find it on the dirty lists, and in particular, |
| 61 | * clear_page_dirty_for_io() will still look at the dirty bits in |
| 62 | * the VM. |
| 63 | * |
| 64 | * Doing this should *normally* only ever be done when a page |
| 65 | * is truncated, and is not actually mapped anywhere at all. However, |
| 66 | * fs/buffer.c does this when it notices that somebody has cleaned |
| 67 | * out all the buffers on a page without actually doing it through |
| 68 | * the VM. Can you say "ext3 is horribly ugly"? Tought you could. |
| 69 | */ |
Linus Torvalds | fba2591 | 2006-12-20 13:46:42 -0800 | [diff] [blame] | 70 | void cancel_dirty_page(struct page *page, unsigned int account_size) |
| 71 | { |
Linus Torvalds | 8368e32 | 2006-12-23 09:25:04 -0800 | [diff] [blame] | 72 | if (TestClearPageDirty(page)) { |
| 73 | struct address_space *mapping = page->mapping; |
| 74 | if (mapping && mapping_cap_account_dirty(mapping)) { |
| 75 | dec_zone_page_state(page, NR_FILE_DIRTY); |
Peter Zijlstra | c9e51e4 | 2007-10-16 23:25:47 -0700 | [diff] [blame] | 76 | dec_bdi_stat(mapping->backing_dev_info, |
| 77 | BDI_RECLAIMABLE); |
Linus Torvalds | 8368e32 | 2006-12-23 09:25:04 -0800 | [diff] [blame] | 78 | if (account_size) |
| 79 | task_io_account_cancelled_write(account_size); |
| 80 | } |
Andrew Morton | 3e67c09 | 2006-12-21 11:00:33 -0800 | [diff] [blame] | 81 | } |
Linus Torvalds | fba2591 | 2006-12-20 13:46:42 -0800 | [diff] [blame] | 82 | } |
Linus Torvalds | 8368e32 | 2006-12-23 09:25:04 -0800 | [diff] [blame] | 83 | EXPORT_SYMBOL(cancel_dirty_page); |
Linus Torvalds | fba2591 | 2006-12-20 13:46:42 -0800 | [diff] [blame] | 84 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 85 | /* |
| 86 | * If truncate cannot remove the fs-private metadata from the page, the page |
| 87 | * becomes anonymous. It will be left on the LRU and may even be mapped into |
Nick Piggin | 54cb882 | 2007-07-19 01:46:59 -0700 | [diff] [blame] | 88 | * user pagetables if we're racing with filemap_fault(). |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 89 | * |
| 90 | * We need to bale out if page->mapping is no longer equal to the original |
| 91 | * mapping. This happens a) when the VM reclaimed the page while we waited on |
Andrew Morton | fc0ecff | 2007-02-10 01:45:39 -0800 | [diff] [blame] | 92 | * its lock, b) when a concurrent invalidate_mapping_pages got there first and |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 93 | * c) when tmpfs swizzles a page between a tmpfs inode and swapper_space. |
| 94 | */ |
| 95 | static void |
| 96 | truncate_complete_page(struct address_space *mapping, struct page *page) |
| 97 | { |
| 98 | if (page->mapping != mapping) |
| 99 | return; |
| 100 | |
Andrew Morton | 3e67c09 | 2006-12-21 11:00:33 -0800 | [diff] [blame] | 101 | cancel_dirty_page(page, PAGE_CACHE_SIZE); |
| 102 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 103 | if (PagePrivate(page)) |
| 104 | do_invalidatepage(page, 0); |
| 105 | |
Nick Piggin | 787d221 | 2007-07-17 04:03:34 -0700 | [diff] [blame] | 106 | remove_from_page_cache(page); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 107 | ClearPageUptodate(page); |
| 108 | ClearPageMappedToDisk(page); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 109 | page_cache_release(page); /* pagecache ref */ |
| 110 | } |
| 111 | |
| 112 | /* |
Andrew Morton | fc0ecff | 2007-02-10 01:45:39 -0800 | [diff] [blame] | 113 | * This is for invalidate_mapping_pages(). That function can be called at |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 114 | * any time, and is not supposed to throw away dirty pages. But pages can |
Nick Piggin | 0fd0e6b | 2006-09-27 01:50:02 -0700 | [diff] [blame] | 115 | * be marked dirty at any time too, so use remove_mapping which safely |
| 116 | * discards clean, unused pages. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 117 | * |
| 118 | * Returns non-zero if the page was successfully invalidated. |
| 119 | */ |
| 120 | static int |
| 121 | invalidate_complete_page(struct address_space *mapping, struct page *page) |
| 122 | { |
Nick Piggin | 0fd0e6b | 2006-09-27 01:50:02 -0700 | [diff] [blame] | 123 | int ret; |
| 124 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 125 | if (page->mapping != mapping) |
| 126 | return 0; |
| 127 | |
| 128 | if (PagePrivate(page) && !try_to_release_page(page, 0)) |
| 129 | return 0; |
| 130 | |
Nick Piggin | 0fd0e6b | 2006-09-27 01:50:02 -0700 | [diff] [blame] | 131 | ret = remove_mapping(mapping, page); |
Nick Piggin | 0fd0e6b | 2006-09-27 01:50:02 -0700 | [diff] [blame] | 132 | |
| 133 | return ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 134 | } |
| 135 | |
| 136 | /** |
Hans Reiser | d733907 | 2006-01-06 00:10:36 -0800 | [diff] [blame] | 137 | * truncate_inode_pages - truncate range of pages specified by start and |
| 138 | * end byte offsets |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 139 | * @mapping: mapping to truncate |
| 140 | * @lstart: offset from which to truncate |
Hans Reiser | d733907 | 2006-01-06 00:10:36 -0800 | [diff] [blame] | 141 | * @lend: offset to which to truncate |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 142 | * |
Hans Reiser | d733907 | 2006-01-06 00:10:36 -0800 | [diff] [blame] | 143 | * Truncate the page cache, removing the pages that are between |
| 144 | * specified offsets (and zeroing out partial page |
| 145 | * (if lstart is not page aligned)). |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 146 | * |
| 147 | * Truncate takes two passes - the first pass is nonblocking. It will not |
| 148 | * block on page locks and it will not block on writeback. The second pass |
| 149 | * will wait. This is to prevent as much IO as possible in the affected region. |
| 150 | * The first pass will remove most pages, so the search cost of the second pass |
| 151 | * is low. |
| 152 | * |
| 153 | * When looking at page->index outside the page lock we need to be careful to |
| 154 | * copy it into a local to avoid races (it could change at any time). |
| 155 | * |
| 156 | * We pass down the cache-hot hint to the page freeing code. Even if the |
| 157 | * mapping is large, it is probably the case that the final pages are the most |
| 158 | * recently touched, and freeing happens in ascending file offset order. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 159 | */ |
Hans Reiser | d733907 | 2006-01-06 00:10:36 -0800 | [diff] [blame] | 160 | void truncate_inode_pages_range(struct address_space *mapping, |
| 161 | loff_t lstart, loff_t lend) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 162 | { |
| 163 | const pgoff_t start = (lstart + PAGE_CACHE_SIZE-1) >> PAGE_CACHE_SHIFT; |
Hans Reiser | d733907 | 2006-01-06 00:10:36 -0800 | [diff] [blame] | 164 | pgoff_t end; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 165 | const unsigned partial = lstart & (PAGE_CACHE_SIZE - 1); |
| 166 | struct pagevec pvec; |
| 167 | pgoff_t next; |
| 168 | int i; |
| 169 | |
| 170 | if (mapping->nrpages == 0) |
| 171 | return; |
| 172 | |
Hans Reiser | d733907 | 2006-01-06 00:10:36 -0800 | [diff] [blame] | 173 | BUG_ON((lend & (PAGE_CACHE_SIZE - 1)) != (PAGE_CACHE_SIZE - 1)); |
| 174 | end = (lend >> PAGE_CACHE_SHIFT); |
| 175 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 176 | pagevec_init(&pvec, 0); |
| 177 | next = start; |
Hans Reiser | d733907 | 2006-01-06 00:10:36 -0800 | [diff] [blame] | 178 | while (next <= end && |
| 179 | pagevec_lookup(&pvec, mapping, next, PAGEVEC_SIZE)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 180 | for (i = 0; i < pagevec_count(&pvec); i++) { |
| 181 | struct page *page = pvec.pages[i]; |
| 182 | pgoff_t page_index = page->index; |
| 183 | |
Hans Reiser | d733907 | 2006-01-06 00:10:36 -0800 | [diff] [blame] | 184 | if (page_index > end) { |
| 185 | next = page_index; |
| 186 | break; |
| 187 | } |
| 188 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 189 | if (page_index > next) |
| 190 | next = page_index; |
| 191 | next++; |
| 192 | if (TestSetPageLocked(page)) |
| 193 | continue; |
| 194 | if (PageWriteback(page)) { |
| 195 | unlock_page(page); |
| 196 | continue; |
| 197 | } |
Nick Piggin | d00806b | 2007-07-19 01:46:57 -0700 | [diff] [blame] | 198 | if (page_mapped(page)) { |
| 199 | unmap_mapping_range(mapping, |
| 200 | (loff_t)page_index<<PAGE_CACHE_SHIFT, |
| 201 | PAGE_CACHE_SIZE, 0); |
| 202 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 203 | truncate_complete_page(mapping, page); |
| 204 | unlock_page(page); |
| 205 | } |
| 206 | pagevec_release(&pvec); |
| 207 | cond_resched(); |
| 208 | } |
| 209 | |
| 210 | if (partial) { |
| 211 | struct page *page = find_lock_page(mapping, start - 1); |
| 212 | if (page) { |
| 213 | wait_on_page_writeback(page); |
| 214 | truncate_partial_page(page, partial); |
| 215 | unlock_page(page); |
| 216 | page_cache_release(page); |
| 217 | } |
| 218 | } |
| 219 | |
| 220 | next = start; |
| 221 | for ( ; ; ) { |
| 222 | cond_resched(); |
| 223 | if (!pagevec_lookup(&pvec, mapping, next, PAGEVEC_SIZE)) { |
| 224 | if (next == start) |
| 225 | break; |
| 226 | next = start; |
| 227 | continue; |
| 228 | } |
Hans Reiser | d733907 | 2006-01-06 00:10:36 -0800 | [diff] [blame] | 229 | if (pvec.pages[0]->index > end) { |
| 230 | pagevec_release(&pvec); |
| 231 | break; |
| 232 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 233 | for (i = 0; i < pagevec_count(&pvec); i++) { |
| 234 | struct page *page = pvec.pages[i]; |
| 235 | |
Hans Reiser | d733907 | 2006-01-06 00:10:36 -0800 | [diff] [blame] | 236 | if (page->index > end) |
| 237 | break; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 238 | lock_page(page); |
| 239 | wait_on_page_writeback(page); |
Nick Piggin | d00806b | 2007-07-19 01:46:57 -0700 | [diff] [blame] | 240 | if (page_mapped(page)) { |
| 241 | unmap_mapping_range(mapping, |
| 242 | (loff_t)page->index<<PAGE_CACHE_SHIFT, |
| 243 | PAGE_CACHE_SIZE, 0); |
| 244 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 245 | if (page->index > next) |
| 246 | next = page->index; |
| 247 | next++; |
| 248 | truncate_complete_page(mapping, page); |
| 249 | unlock_page(page); |
| 250 | } |
| 251 | pagevec_release(&pvec); |
| 252 | } |
| 253 | } |
Hans Reiser | d733907 | 2006-01-06 00:10:36 -0800 | [diff] [blame] | 254 | EXPORT_SYMBOL(truncate_inode_pages_range); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 255 | |
Hans Reiser | d733907 | 2006-01-06 00:10:36 -0800 | [diff] [blame] | 256 | /** |
| 257 | * truncate_inode_pages - truncate *all* the pages from an offset |
| 258 | * @mapping: mapping to truncate |
| 259 | * @lstart: offset from which to truncate |
| 260 | * |
Jes Sorensen | 1b1dcc1 | 2006-01-09 15:59:24 -0800 | [diff] [blame] | 261 | * Called under (and serialised by) inode->i_mutex. |
Hans Reiser | d733907 | 2006-01-06 00:10:36 -0800 | [diff] [blame] | 262 | */ |
| 263 | void truncate_inode_pages(struct address_space *mapping, loff_t lstart) |
| 264 | { |
| 265 | truncate_inode_pages_range(mapping, lstart, (loff_t)-1); |
| 266 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 267 | EXPORT_SYMBOL(truncate_inode_pages); |
| 268 | |
Andrew Morton | fc9a07e | 2007-07-15 23:38:14 -0700 | [diff] [blame] | 269 | unsigned long __invalidate_mapping_pages(struct address_space *mapping, |
| 270 | pgoff_t start, pgoff_t end, bool be_atomic) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 271 | { |
| 272 | struct pagevec pvec; |
| 273 | pgoff_t next = start; |
| 274 | unsigned long ret = 0; |
| 275 | int i; |
| 276 | |
| 277 | pagevec_init(&pvec, 0); |
| 278 | while (next <= end && |
| 279 | pagevec_lookup(&pvec, mapping, next, PAGEVEC_SIZE)) { |
| 280 | for (i = 0; i < pagevec_count(&pvec); i++) { |
| 281 | struct page *page = pvec.pages[i]; |
NeilBrown | e0f2360 | 2006-06-23 02:05:48 -0700 | [diff] [blame] | 282 | pgoff_t index; |
| 283 | int lock_failed; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 284 | |
NeilBrown | e0f2360 | 2006-06-23 02:05:48 -0700 | [diff] [blame] | 285 | lock_failed = TestSetPageLocked(page); |
| 286 | |
| 287 | /* |
| 288 | * We really shouldn't be looking at the ->index of an |
| 289 | * unlocked page. But we're not allowed to lock these |
| 290 | * pages. So we rely upon nobody altering the ->index |
| 291 | * of this (pinned-by-us) page. |
| 292 | */ |
| 293 | index = page->index; |
| 294 | if (index > next) |
| 295 | next = index; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 296 | next++; |
NeilBrown | e0f2360 | 2006-06-23 02:05:48 -0700 | [diff] [blame] | 297 | if (lock_failed) |
| 298 | continue; |
| 299 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 300 | if (PageDirty(page) || PageWriteback(page)) |
| 301 | goto unlock; |
| 302 | if (page_mapped(page)) |
| 303 | goto unlock; |
| 304 | ret += invalidate_complete_page(mapping, page); |
| 305 | unlock: |
| 306 | unlock_page(page); |
| 307 | if (next > end) |
| 308 | break; |
| 309 | } |
| 310 | pagevec_release(&pvec); |
Andrew Morton | fc9a07e | 2007-07-15 23:38:14 -0700 | [diff] [blame] | 311 | if (likely(!be_atomic)) |
| 312 | cond_resched(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 313 | } |
| 314 | return ret; |
| 315 | } |
Andrew Morton | fc9a07e | 2007-07-15 23:38:14 -0700 | [diff] [blame] | 316 | |
| 317 | /** |
| 318 | * invalidate_mapping_pages - Invalidate all the unlocked pages of one inode |
| 319 | * @mapping: the address_space which holds the pages to invalidate |
| 320 | * @start: the offset 'from' which to invalidate |
| 321 | * @end: the offset 'to' which to invalidate (inclusive) |
| 322 | * |
| 323 | * This function only removes the unlocked pages, if you want to |
| 324 | * remove all the pages of one inode, you must call truncate_inode_pages. |
| 325 | * |
| 326 | * invalidate_mapping_pages() will not block on IO activity. It will not |
| 327 | * invalidate pages which are dirty, locked, under writeback or mapped into |
| 328 | * pagetables. |
| 329 | */ |
| 330 | unsigned long invalidate_mapping_pages(struct address_space *mapping, |
| 331 | pgoff_t start, pgoff_t end) |
| 332 | { |
| 333 | return __invalidate_mapping_pages(mapping, start, end, false); |
| 334 | } |
Anton Altaparmakov | 54bc485 | 2007-02-10 01:45:38 -0800 | [diff] [blame] | 335 | EXPORT_SYMBOL(invalidate_mapping_pages); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 336 | |
Andrew Morton | bd4c8ce | 2006-09-30 23:29:29 -0700 | [diff] [blame] | 337 | /* |
| 338 | * This is like invalidate_complete_page(), except it ignores the page's |
| 339 | * refcount. We do this because invalidate_inode_pages2() needs stronger |
| 340 | * invalidation guarantees, and cannot afford to leave pages behind because |
Anderson Briglia | 2706a1b | 2007-07-15 23:38:09 -0700 | [diff] [blame] | 341 | * shrink_page_list() has a temp ref on them, or because they're transiently |
| 342 | * sitting in the lru_cache_add() pagevecs. |
Andrew Morton | bd4c8ce | 2006-09-30 23:29:29 -0700 | [diff] [blame] | 343 | */ |
| 344 | static int |
| 345 | invalidate_complete_page2(struct address_space *mapping, struct page *page) |
| 346 | { |
| 347 | if (page->mapping != mapping) |
| 348 | return 0; |
| 349 | |
Trond Myklebust | 887ed2f | 2006-10-11 01:21:58 -0700 | [diff] [blame] | 350 | if (PagePrivate(page) && !try_to_release_page(page, GFP_KERNEL)) |
Andrew Morton | bd4c8ce | 2006-09-30 23:29:29 -0700 | [diff] [blame] | 351 | return 0; |
| 352 | |
| 353 | write_lock_irq(&mapping->tree_lock); |
| 354 | if (PageDirty(page)) |
| 355 | goto failed; |
| 356 | |
| 357 | BUG_ON(PagePrivate(page)); |
| 358 | __remove_from_page_cache(page); |
| 359 | write_unlock_irq(&mapping->tree_lock); |
| 360 | ClearPageUptodate(page); |
| 361 | page_cache_release(page); /* pagecache ref */ |
| 362 | return 1; |
| 363 | failed: |
| 364 | write_unlock_irq(&mapping->tree_lock); |
| 365 | return 0; |
| 366 | } |
| 367 | |
Trond Myklebust | e3db769 | 2007-01-10 23:15:39 -0800 | [diff] [blame] | 368 | static int do_launder_page(struct address_space *mapping, struct page *page) |
| 369 | { |
| 370 | if (!PageDirty(page)) |
| 371 | return 0; |
| 372 | if (page->mapping != mapping || mapping->a_ops->launder_page == NULL) |
| 373 | return 0; |
| 374 | return mapping->a_ops->launder_page(page); |
| 375 | } |
| 376 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 377 | /** |
| 378 | * invalidate_inode_pages2_range - remove range of pages from an address_space |
Martin Waitz | 67be2dd | 2005-05-01 08:59:26 -0700 | [diff] [blame] | 379 | * @mapping: the address_space |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 380 | * @start: the page offset 'from' which to invalidate |
| 381 | * @end: the page offset 'to' which to invalidate (inclusive) |
| 382 | * |
| 383 | * Any pages which are found to be mapped into pagetables are unmapped prior to |
| 384 | * invalidation. |
| 385 | * |
| 386 | * Returns -EIO if any pages could not be invalidated. |
| 387 | */ |
| 388 | int invalidate_inode_pages2_range(struct address_space *mapping, |
| 389 | pgoff_t start, pgoff_t end) |
| 390 | { |
| 391 | struct pagevec pvec; |
| 392 | pgoff_t next; |
| 393 | int i; |
| 394 | int ret = 0; |
| 395 | int did_range_unmap = 0; |
| 396 | int wrapped = 0; |
| 397 | |
| 398 | pagevec_init(&pvec, 0); |
| 399 | next = start; |
Trond Myklebust | 7b965e0 | 2007-02-28 20:13:55 -0800 | [diff] [blame] | 400 | while (next <= end && !wrapped && |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 401 | pagevec_lookup(&pvec, mapping, next, |
| 402 | min(end - next, (pgoff_t)PAGEVEC_SIZE - 1) + 1)) { |
Trond Myklebust | 7b965e0 | 2007-02-28 20:13:55 -0800 | [diff] [blame] | 403 | for (i = 0; i < pagevec_count(&pvec); i++) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 404 | struct page *page = pvec.pages[i]; |
| 405 | pgoff_t page_index; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 406 | |
| 407 | lock_page(page); |
| 408 | if (page->mapping != mapping) { |
| 409 | unlock_page(page); |
| 410 | continue; |
| 411 | } |
| 412 | page_index = page->index; |
| 413 | next = page_index + 1; |
| 414 | if (next == 0) |
| 415 | wrapped = 1; |
| 416 | if (page_index > end) { |
| 417 | unlock_page(page); |
| 418 | break; |
| 419 | } |
| 420 | wait_on_page_writeback(page); |
Nick Piggin | d00806b | 2007-07-19 01:46:57 -0700 | [diff] [blame] | 421 | if (page_mapped(page)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 422 | if (!did_range_unmap) { |
| 423 | /* |
| 424 | * Zap the rest of the file in one hit. |
| 425 | */ |
| 426 | unmap_mapping_range(mapping, |
Oleg Drokin | 479ef59 | 2005-11-23 13:37:47 -0800 | [diff] [blame] | 427 | (loff_t)page_index<<PAGE_CACHE_SHIFT, |
| 428 | (loff_t)(end - page_index + 1) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 429 | << PAGE_CACHE_SHIFT, |
| 430 | 0); |
| 431 | did_range_unmap = 1; |
| 432 | } else { |
| 433 | /* |
| 434 | * Just zap this page |
| 435 | */ |
| 436 | unmap_mapping_range(mapping, |
Oleg Drokin | 479ef59 | 2005-11-23 13:37:47 -0800 | [diff] [blame] | 437 | (loff_t)page_index<<PAGE_CACHE_SHIFT, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 438 | PAGE_CACHE_SIZE, 0); |
| 439 | } |
| 440 | } |
Nick Piggin | d00806b | 2007-07-19 01:46:57 -0700 | [diff] [blame] | 441 | BUG_ON(page_mapped(page)); |
Trond Myklebust | e3db769 | 2007-01-10 23:15:39 -0800 | [diff] [blame] | 442 | ret = do_launder_page(mapping, page); |
| 443 | if (ret == 0 && !invalidate_complete_page2(mapping, page)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 444 | ret = -EIO; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 445 | unlock_page(page); |
| 446 | } |
| 447 | pagevec_release(&pvec); |
| 448 | cond_resched(); |
| 449 | } |
| 450 | return ret; |
| 451 | } |
| 452 | EXPORT_SYMBOL_GPL(invalidate_inode_pages2_range); |
| 453 | |
| 454 | /** |
| 455 | * invalidate_inode_pages2 - remove all pages from an address_space |
Martin Waitz | 67be2dd | 2005-05-01 08:59:26 -0700 | [diff] [blame] | 456 | * @mapping: the address_space |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 457 | * |
| 458 | * Any pages which are found to be mapped into pagetables are unmapped prior to |
| 459 | * invalidation. |
| 460 | * |
| 461 | * Returns -EIO if any pages could not be invalidated. |
| 462 | */ |
| 463 | int invalidate_inode_pages2(struct address_space *mapping) |
| 464 | { |
| 465 | return invalidate_inode_pages2_range(mapping, 0, -1); |
| 466 | } |
| 467 | EXPORT_SYMBOL_GPL(invalidate_inode_pages2); |