David Howells | 08e0e7c | 2007-04-26 15:55:03 -0700 | [diff] [blame] | 1 | /* AFS filesystem file handling |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2 | * |
David Howells | 08e0e7c | 2007-04-26 15:55:03 -0700 | [diff] [blame] | 3 | * Copyright (C) 2002, 2007 Red Hat, Inc. All Rights Reserved. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 4 | * Written by David Howells (dhowells@redhat.com) |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or |
| 7 | * modify it under the terms of the GNU General Public License |
| 8 | * as published by the Free Software Foundation; either version |
| 9 | * 2 of the License, or (at your option) any later version. |
| 10 | */ |
| 11 | |
| 12 | #include <linux/kernel.h> |
| 13 | #include <linux/module.h> |
| 14 | #include <linux/init.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 15 | #include <linux/fs.h> |
| 16 | #include <linux/pagemap.h> |
David Howells | 31143d5 | 2007-05-09 02:33:46 -0700 | [diff] [blame] | 17 | #include <linux/writeback.h> |
Tejun Heo | 5a0e3ad | 2010-03-24 17:04:11 +0900 | [diff] [blame] | 18 | #include <linux/gfp.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 19 | #include "internal.h" |
| 20 | |
David Howells | 416351f | 2007-05-09 02:33:45 -0700 | [diff] [blame] | 21 | static int afs_readpage(struct file *file, struct page *page); |
Lukas Czerner | d47992f | 2013-05-21 23:17:23 -0400 | [diff] [blame] | 22 | static void afs_invalidatepage(struct page *page, unsigned int offset, |
| 23 | unsigned int length); |
David Howells | 416351f | 2007-05-09 02:33:45 -0700 | [diff] [blame] | 24 | static int afs_releasepage(struct page *page, gfp_t gfp_flags); |
David Howells | 31143d5 | 2007-05-09 02:33:46 -0700 | [diff] [blame] | 25 | static int afs_launder_page(struct page *page); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 26 | |
David Howells | 9b3f26c | 2009-04-03 16:42:41 +0100 | [diff] [blame] | 27 | static int afs_readpages(struct file *filp, struct address_space *mapping, |
| 28 | struct list_head *pages, unsigned nr_pages); |
| 29 | |
David Howells | 00d3b7a | 2007-04-26 15:57:07 -0700 | [diff] [blame] | 30 | const struct file_operations afs_file_operations = { |
| 31 | .open = afs_open, |
David Howells | 7286fad | 2017-03-16 16:27:45 +0000 | [diff] [blame] | 32 | .flush = afs_flush, |
David Howells | 00d3b7a | 2007-04-26 15:57:07 -0700 | [diff] [blame] | 33 | .release = afs_release, |
| 34 | .llseek = generic_file_llseek, |
Al Viro | aad4f8b | 2014-04-02 14:33:16 -0400 | [diff] [blame] | 35 | .read_iter = generic_file_read_iter, |
Al Viro | 50b5551 | 2014-04-03 14:13:46 -0400 | [diff] [blame] | 36 | .write_iter = afs_file_write, |
David Howells | 00d3b7a | 2007-04-26 15:57:07 -0700 | [diff] [blame] | 37 | .mmap = generic_file_readonly_mmap, |
Jens Axboe | 5ffc4ef | 2007-06-01 11:49:19 +0200 | [diff] [blame] | 38 | .splice_read = generic_file_splice_read, |
David Howells | 31143d5 | 2007-05-09 02:33:46 -0700 | [diff] [blame] | 39 | .fsync = afs_fsync, |
David Howells | e8d6c55 | 2007-07-15 23:40:12 -0700 | [diff] [blame] | 40 | .lock = afs_lock, |
| 41 | .flock = afs_flock, |
David Howells | 00d3b7a | 2007-04-26 15:57:07 -0700 | [diff] [blame] | 42 | }; |
| 43 | |
Arjan van de Ven | 754661f | 2007-02-12 00:55:38 -0800 | [diff] [blame] | 44 | const struct inode_operations afs_file_inode_operations = { |
David Howells | 416351f | 2007-05-09 02:33:45 -0700 | [diff] [blame] | 45 | .getattr = afs_getattr, |
David Howells | 31143d5 | 2007-05-09 02:33:46 -0700 | [diff] [blame] | 46 | .setattr = afs_setattr, |
David Howells | 00d3b7a | 2007-04-26 15:57:07 -0700 | [diff] [blame] | 47 | .permission = afs_permission, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 48 | }; |
| 49 | |
Christoph Hellwig | f5e54d6 | 2006-06-28 04:26:44 -0700 | [diff] [blame] | 50 | const struct address_space_operations afs_fs_aops = { |
David Howells | 416351f | 2007-05-09 02:33:45 -0700 | [diff] [blame] | 51 | .readpage = afs_readpage, |
David Howells | 9b3f26c | 2009-04-03 16:42:41 +0100 | [diff] [blame] | 52 | .readpages = afs_readpages, |
David Howells | 31143d5 | 2007-05-09 02:33:46 -0700 | [diff] [blame] | 53 | .set_page_dirty = afs_set_page_dirty, |
| 54 | .launder_page = afs_launder_page, |
David Howells | 416351f | 2007-05-09 02:33:45 -0700 | [diff] [blame] | 55 | .releasepage = afs_releasepage, |
| 56 | .invalidatepage = afs_invalidatepage, |
Nick Piggin | 15b4650 | 2008-10-15 22:04:32 -0700 | [diff] [blame] | 57 | .write_begin = afs_write_begin, |
| 58 | .write_end = afs_write_end, |
David Howells | 31143d5 | 2007-05-09 02:33:46 -0700 | [diff] [blame] | 59 | .writepage = afs_writepage, |
| 60 | .writepages = afs_writepages, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 61 | }; |
| 62 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 63 | /* |
David Howells | 00d3b7a | 2007-04-26 15:57:07 -0700 | [diff] [blame] | 64 | * open an AFS file or directory and attach a key to it |
| 65 | */ |
| 66 | int afs_open(struct inode *inode, struct file *file) |
| 67 | { |
| 68 | struct afs_vnode *vnode = AFS_FS_I(inode); |
| 69 | struct key *key; |
David Howells | 260a980 | 2007-04-26 15:59:35 -0700 | [diff] [blame] | 70 | int ret; |
David Howells | 00d3b7a | 2007-04-26 15:57:07 -0700 | [diff] [blame] | 71 | |
David Howells | 416351f | 2007-05-09 02:33:45 -0700 | [diff] [blame] | 72 | _enter("{%x:%u},", vnode->fid.vid, vnode->fid.vnode); |
David Howells | 00d3b7a | 2007-04-26 15:57:07 -0700 | [diff] [blame] | 73 | |
| 74 | key = afs_request_key(vnode->volume->cell); |
| 75 | if (IS_ERR(key)) { |
| 76 | _leave(" = %ld [key]", PTR_ERR(key)); |
| 77 | return PTR_ERR(key); |
| 78 | } |
| 79 | |
David Howells | 260a980 | 2007-04-26 15:59:35 -0700 | [diff] [blame] | 80 | ret = afs_validate(vnode, key); |
| 81 | if (ret < 0) { |
| 82 | _leave(" = %d [val]", ret); |
| 83 | return ret; |
| 84 | } |
| 85 | |
David Howells | 00d3b7a | 2007-04-26 15:57:07 -0700 | [diff] [blame] | 86 | file->private_data = key; |
| 87 | _leave(" = 0"); |
| 88 | return 0; |
| 89 | } |
| 90 | |
| 91 | /* |
| 92 | * release an AFS file or directory and discard its key |
| 93 | */ |
| 94 | int afs_release(struct inode *inode, struct file *file) |
| 95 | { |
| 96 | struct afs_vnode *vnode = AFS_FS_I(inode); |
| 97 | |
David Howells | 416351f | 2007-05-09 02:33:45 -0700 | [diff] [blame] | 98 | _enter("{%x:%u},", vnode->fid.vid, vnode->fid.vnode); |
David Howells | 00d3b7a | 2007-04-26 15:57:07 -0700 | [diff] [blame] | 99 | |
| 100 | key_put(file->private_data); |
| 101 | _leave(" = 0"); |
| 102 | return 0; |
| 103 | } |
| 104 | |
Matt Kraai | 6566abd | 2009-04-17 12:56:38 +0100 | [diff] [blame] | 105 | #ifdef CONFIG_AFS_FSCACHE |
David Howells | 00d3b7a | 2007-04-26 15:57:07 -0700 | [diff] [blame] | 106 | /* |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 107 | * deal with notification that a page was read from the cache |
| 108 | */ |
David Howells | 9b3f26c | 2009-04-03 16:42:41 +0100 | [diff] [blame] | 109 | static void afs_file_readpage_read_complete(struct page *page, |
| 110 | void *data, |
| 111 | int error) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 112 | { |
David Howells | 9b3f26c | 2009-04-03 16:42:41 +0100 | [diff] [blame] | 113 | _enter("%p,%p,%d", page, data, error); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 114 | |
David Howells | 9b3f26c | 2009-04-03 16:42:41 +0100 | [diff] [blame] | 115 | /* if the read completes with an error, we just unlock the page and let |
| 116 | * the VM reissue the readpage */ |
| 117 | if (!error) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 118 | SetPageUptodate(page); |
| 119 | unlock_page(page); |
David Howells | ec26815 | 2007-04-26 15:49:28 -0700 | [diff] [blame] | 120 | } |
Matt Kraai | 6566abd | 2009-04-17 12:56:38 +0100 | [diff] [blame] | 121 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 122 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 123 | /* |
Al Viro | f6d335c | 2010-05-21 15:27:09 +0100 | [diff] [blame] | 124 | * read page from file, directory or symlink, given a key to use |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 125 | */ |
Sami Tolvanen | 53f4adf | 2018-03-02 09:02:16 -0800 | [diff] [blame] | 126 | static int __afs_page_filler(struct key *key, struct page *page) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 127 | { |
Al Viro | f6d335c | 2010-05-21 15:27:09 +0100 | [diff] [blame] | 128 | struct inode *inode = page->mapping->host; |
| 129 | struct afs_vnode *vnode = AFS_FS_I(inode); |
David Howells | 08e0e7c | 2007-04-26 15:55:03 -0700 | [diff] [blame] | 130 | size_t len; |
| 131 | off_t offset; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 132 | int ret; |
| 133 | |
David Howells | 00d3b7a | 2007-04-26 15:57:07 -0700 | [diff] [blame] | 134 | _enter("{%x},{%lu},{%lu}", key_serial(key), inode->i_ino, page->index); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 135 | |
Matt Mackall | cd7619d | 2005-05-01 08:59:01 -0700 | [diff] [blame] | 136 | BUG_ON(!PageLocked(page)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 137 | |
| 138 | ret = -ESTALE; |
David Howells | 08e0e7c | 2007-04-26 15:55:03 -0700 | [diff] [blame] | 139 | if (test_bit(AFS_VNODE_DELETED, &vnode->flags)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 140 | goto error; |
| 141 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 142 | /* is it cached? */ |
David Howells | 9b3f26c | 2009-04-03 16:42:41 +0100 | [diff] [blame] | 143 | #ifdef CONFIG_AFS_FSCACHE |
| 144 | ret = fscache_read_or_alloc_page(vnode->cache, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 145 | page, |
| 146 | afs_file_readpage_read_complete, |
| 147 | NULL, |
| 148 | GFP_KERNEL); |
| 149 | #else |
| 150 | ret = -ENOBUFS; |
| 151 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 152 | switch (ret) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 153 | /* read BIO submitted (page in cache) */ |
| 154 | case 0: |
| 155 | break; |
| 156 | |
David Howells | 9b3f26c | 2009-04-03 16:42:41 +0100 | [diff] [blame] | 157 | /* page not yet cached */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 158 | case -ENODATA: |
David Howells | 9b3f26c | 2009-04-03 16:42:41 +0100 | [diff] [blame] | 159 | _debug("cache said ENODATA"); |
| 160 | goto go_on; |
| 161 | |
| 162 | /* page will not be cached */ |
| 163 | case -ENOBUFS: |
| 164 | _debug("cache said ENOBUFS"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 165 | default: |
David Howells | 9b3f26c | 2009-04-03 16:42:41 +0100 | [diff] [blame] | 166 | go_on: |
Kirill A. Shutemov | 09cbfea | 2016-04-01 15:29:47 +0300 | [diff] [blame] | 167 | offset = page->index << PAGE_SHIFT; |
David Howells | 08e0e7c | 2007-04-26 15:55:03 -0700 | [diff] [blame] | 168 | len = min_t(size_t, i_size_read(inode) - offset, PAGE_SIZE); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 169 | |
| 170 | /* read the contents of the file from the server into the |
| 171 | * page */ |
David Howells | 00d3b7a | 2007-04-26 15:57:07 -0700 | [diff] [blame] | 172 | ret = afs_vnode_fetch_data(vnode, key, offset, len, page); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 173 | if (ret < 0) { |
David Howells | 08e0e7c | 2007-04-26 15:55:03 -0700 | [diff] [blame] | 174 | if (ret == -ENOENT) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 175 | _debug("got NOENT from server" |
| 176 | " - marking file deleted and stale"); |
David Howells | 08e0e7c | 2007-04-26 15:55:03 -0700 | [diff] [blame] | 177 | set_bit(AFS_VNODE_DELETED, &vnode->flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 178 | ret = -ESTALE; |
| 179 | } |
David Howells | 9b3f26c | 2009-04-03 16:42:41 +0100 | [diff] [blame] | 180 | |
| 181 | #ifdef CONFIG_AFS_FSCACHE |
| 182 | fscache_uncache_page(vnode->cache, page); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 183 | #endif |
David Howells | 9b3f26c | 2009-04-03 16:42:41 +0100 | [diff] [blame] | 184 | BUG_ON(PageFsCache(page)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 185 | goto error; |
| 186 | } |
| 187 | |
| 188 | SetPageUptodate(page); |
| 189 | |
David Howells | 9b3f26c | 2009-04-03 16:42:41 +0100 | [diff] [blame] | 190 | /* send the page to the cache */ |
| 191 | #ifdef CONFIG_AFS_FSCACHE |
| 192 | if (PageFsCache(page) && |
| 193 | fscache_write_page(vnode->cache, page, GFP_KERNEL) != 0) { |
| 194 | fscache_uncache_page(vnode->cache, page); |
| 195 | BUG_ON(PageFsCache(page)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 196 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 197 | #endif |
David Howells | 9b3f26c | 2009-04-03 16:42:41 +0100 | [diff] [blame] | 198 | unlock_page(page); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 199 | } |
| 200 | |
| 201 | _leave(" = 0"); |
| 202 | return 0; |
| 203 | |
David Howells | 08e0e7c | 2007-04-26 15:55:03 -0700 | [diff] [blame] | 204 | error: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 205 | SetPageError(page); |
| 206 | unlock_page(page); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 207 | _leave(" = %d", ret); |
| 208 | return ret; |
David Howells | ec26815 | 2007-04-26 15:49:28 -0700 | [diff] [blame] | 209 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 210 | |
Sami Tolvanen | 53f4adf | 2018-03-02 09:02:16 -0800 | [diff] [blame] | 211 | int afs_page_filler(struct file *data, struct page *page) |
| 212 | { |
| 213 | struct key *key = (struct key *)data; |
| 214 | |
| 215 | return __afs_page_filler(key, page); |
| 216 | } |
| 217 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 218 | /* |
Al Viro | f6d335c | 2010-05-21 15:27:09 +0100 | [diff] [blame] | 219 | * read page from file, directory or symlink, given a file to nominate the key |
| 220 | * to be used |
| 221 | */ |
| 222 | static int afs_readpage(struct file *file, struct page *page) |
| 223 | { |
| 224 | struct key *key; |
| 225 | int ret; |
| 226 | |
| 227 | if (file) { |
| 228 | key = file->private_data; |
| 229 | ASSERT(key != NULL); |
Sami Tolvanen | 53f4adf | 2018-03-02 09:02:16 -0800 | [diff] [blame] | 230 | ret = __afs_page_filler(key, page); |
Al Viro | f6d335c | 2010-05-21 15:27:09 +0100 | [diff] [blame] | 231 | } else { |
| 232 | struct inode *inode = page->mapping->host; |
| 233 | key = afs_request_key(AFS_FS_S(inode->i_sb)->volume->cell); |
| 234 | if (IS_ERR(key)) { |
| 235 | ret = PTR_ERR(key); |
| 236 | } else { |
Sami Tolvanen | 53f4adf | 2018-03-02 09:02:16 -0800 | [diff] [blame] | 237 | ret = __afs_page_filler(key, page); |
Al Viro | f6d335c | 2010-05-21 15:27:09 +0100 | [diff] [blame] | 238 | key_put(key); |
| 239 | } |
| 240 | } |
| 241 | return ret; |
| 242 | } |
| 243 | |
| 244 | /* |
David Howells | 9b3f26c | 2009-04-03 16:42:41 +0100 | [diff] [blame] | 245 | * read a set of pages |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 246 | */ |
David Howells | 9b3f26c | 2009-04-03 16:42:41 +0100 | [diff] [blame] | 247 | static int afs_readpages(struct file *file, struct address_space *mapping, |
| 248 | struct list_head *pages, unsigned nr_pages) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 249 | { |
Al Viro | f6d335c | 2010-05-21 15:27:09 +0100 | [diff] [blame] | 250 | struct key *key = file->private_data; |
David Howells | 9b3f26c | 2009-04-03 16:42:41 +0100 | [diff] [blame] | 251 | struct afs_vnode *vnode; |
| 252 | int ret = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 253 | |
Al Viro | f6d335c | 2010-05-21 15:27:09 +0100 | [diff] [blame] | 254 | _enter("{%d},{%lu},,%d", |
| 255 | key_serial(key), mapping->host->i_ino, nr_pages); |
| 256 | |
| 257 | ASSERT(key != NULL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 258 | |
David Howells | 9b3f26c | 2009-04-03 16:42:41 +0100 | [diff] [blame] | 259 | vnode = AFS_FS_I(mapping->host); |
Dan Carpenter | ad2a8e6 | 2012-03-20 16:58:06 +0000 | [diff] [blame] | 260 | if (test_bit(AFS_VNODE_DELETED, &vnode->flags)) { |
David Howells | 9b3f26c | 2009-04-03 16:42:41 +0100 | [diff] [blame] | 261 | _leave(" = -ESTALE"); |
| 262 | return -ESTALE; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 263 | } |
| 264 | |
David Howells | 9b3f26c | 2009-04-03 16:42:41 +0100 | [diff] [blame] | 265 | /* attempt to read as many of the pages as possible */ |
| 266 | #ifdef CONFIG_AFS_FSCACHE |
| 267 | ret = fscache_read_or_alloc_pages(vnode->cache, |
| 268 | mapping, |
| 269 | pages, |
| 270 | &nr_pages, |
| 271 | afs_file_readpage_read_complete, |
| 272 | NULL, |
| 273 | mapping_gfp_mask(mapping)); |
| 274 | #else |
| 275 | ret = -ENOBUFS; |
| 276 | #endif |
| 277 | |
| 278 | switch (ret) { |
| 279 | /* all pages are being read from the cache */ |
| 280 | case 0: |
| 281 | BUG_ON(!list_empty(pages)); |
| 282 | BUG_ON(nr_pages != 0); |
| 283 | _leave(" = 0 [reading all]"); |
| 284 | return 0; |
| 285 | |
| 286 | /* there were pages that couldn't be read from the cache */ |
| 287 | case -ENODATA: |
| 288 | case -ENOBUFS: |
| 289 | break; |
| 290 | |
| 291 | /* other error */ |
| 292 | default: |
| 293 | _leave(" = %d", ret); |
| 294 | return ret; |
| 295 | } |
| 296 | |
| 297 | /* load the missing pages from the network */ |
Al Viro | f6d335c | 2010-05-21 15:27:09 +0100 | [diff] [blame] | 298 | ret = read_cache_pages(mapping, pages, afs_page_filler, key); |
David Howells | 9b3f26c | 2009-04-03 16:42:41 +0100 | [diff] [blame] | 299 | |
| 300 | _leave(" = %d [netting]", ret); |
| 301 | return ret; |
David Howells | ec26815 | 2007-04-26 15:49:28 -0700 | [diff] [blame] | 302 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 303 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 304 | /* |
David Howells | 31143d5 | 2007-05-09 02:33:46 -0700 | [diff] [blame] | 305 | * write back a dirty page |
| 306 | */ |
| 307 | static int afs_launder_page(struct page *page) |
| 308 | { |
| 309 | _enter("{%lu}", page->index); |
| 310 | |
| 311 | return 0; |
| 312 | } |
| 313 | |
| 314 | /* |
David Howells | 9b3f26c | 2009-04-03 16:42:41 +0100 | [diff] [blame] | 315 | * invalidate part or all of a page |
| 316 | * - release a page and clean up its private data if offset is 0 (indicating |
| 317 | * the entire page) |
| 318 | */ |
Lukas Czerner | d47992f | 2013-05-21 23:17:23 -0400 | [diff] [blame] | 319 | static void afs_invalidatepage(struct page *page, unsigned int offset, |
| 320 | unsigned int length) |
David Howells | 9b3f26c | 2009-04-03 16:42:41 +0100 | [diff] [blame] | 321 | { |
| 322 | struct afs_writeback *wb = (struct afs_writeback *) page_private(page); |
| 323 | |
Lukas Czerner | d47992f | 2013-05-21 23:17:23 -0400 | [diff] [blame] | 324 | _enter("{%lu},%u,%u", page->index, offset, length); |
David Howells | 9b3f26c | 2009-04-03 16:42:41 +0100 | [diff] [blame] | 325 | |
| 326 | BUG_ON(!PageLocked(page)); |
| 327 | |
| 328 | /* we clean up only if the entire page is being invalidated */ |
Kirill A. Shutemov | 09cbfea | 2016-04-01 15:29:47 +0300 | [diff] [blame] | 329 | if (offset == 0 && length == PAGE_SIZE) { |
David Howells | 9b3f26c | 2009-04-03 16:42:41 +0100 | [diff] [blame] | 330 | #ifdef CONFIG_AFS_FSCACHE |
| 331 | if (PageFsCache(page)) { |
| 332 | struct afs_vnode *vnode = AFS_FS_I(page->mapping->host); |
| 333 | fscache_wait_on_page_write(vnode->cache, page); |
| 334 | fscache_uncache_page(vnode->cache, page); |
David Howells | 9b3f26c | 2009-04-03 16:42:41 +0100 | [diff] [blame] | 335 | } |
| 336 | #endif |
| 337 | |
| 338 | if (PagePrivate(page)) { |
| 339 | if (wb && !PageWriteback(page)) { |
| 340 | set_page_private(page, 0); |
| 341 | afs_put_writeback(wb); |
| 342 | } |
| 343 | |
| 344 | if (!page_private(page)) |
| 345 | ClearPagePrivate(page); |
| 346 | } |
| 347 | } |
| 348 | |
| 349 | _leave(""); |
| 350 | } |
| 351 | |
| 352 | /* |
| 353 | * release a page and clean up its private state if it's not busy |
| 354 | * - return true if the page can now be released, false if not |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 355 | */ |
David Howells | 416351f | 2007-05-09 02:33:45 -0700 | [diff] [blame] | 356 | static int afs_releasepage(struct page *page, gfp_t gfp_flags) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 357 | { |
David Howells | 9b3f26c | 2009-04-03 16:42:41 +0100 | [diff] [blame] | 358 | struct afs_writeback *wb = (struct afs_writeback *) page_private(page); |
David Howells | 416351f | 2007-05-09 02:33:45 -0700 | [diff] [blame] | 359 | struct afs_vnode *vnode = AFS_FS_I(page->mapping->host); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 360 | |
David Howells | 416351f | 2007-05-09 02:33:45 -0700 | [diff] [blame] | 361 | _enter("{{%x:%u}[%lu],%lx},%x", |
| 362 | vnode->fid.vid, vnode->fid.vnode, page->index, page->flags, |
| 363 | gfp_flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 364 | |
David Howells | 9b3f26c | 2009-04-03 16:42:41 +0100 | [diff] [blame] | 365 | /* deny if page is being written to the cache and the caller hasn't |
| 366 | * elected to wait */ |
| 367 | #ifdef CONFIG_AFS_FSCACHE |
David Howells | 201a154 | 2009-11-19 18:11:35 +0000 | [diff] [blame] | 368 | if (!fscache_maybe_release_page(vnode->cache, page, gfp_flags)) { |
| 369 | _leave(" = F [cache busy]"); |
| 370 | return 0; |
David Howells | 9b3f26c | 2009-04-03 16:42:41 +0100 | [diff] [blame] | 371 | } |
| 372 | #endif |
| 373 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 374 | if (PagePrivate(page)) { |
David Howells | 9b3f26c | 2009-04-03 16:42:41 +0100 | [diff] [blame] | 375 | if (wb) { |
| 376 | set_page_private(page, 0); |
| 377 | afs_put_writeback(wb); |
| 378 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 379 | ClearPagePrivate(page); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 380 | } |
| 381 | |
David Howells | 9b3f26c | 2009-04-03 16:42:41 +0100 | [diff] [blame] | 382 | /* indicate that the page can be released */ |
| 383 | _leave(" = T"); |
| 384 | return 1; |
David Howells | ec26815 | 2007-04-26 15:49:28 -0700 | [diff] [blame] | 385 | } |