1/* 2 * fs/cifs/fscache.c - CIFS filesystem cache interface 3 * 4 * Copyright (c) 2010 Novell, Inc. 5 * Author(s): Suresh Jayaraman (sjayaraman@suse.de> 6 * 7 * This library is free software; you can redistribute it and/or modify 8 * it under the terms of the GNU Lesser General Public License as published 9 * by the Free Software Foundation; either version 2.1 of the License, or 10 * (at your option) any later version. 11 * 12 * This library is distributed in the hope that it will be useful, 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See 15 * the GNU Lesser General Public License for more details. 16 * 17 * You should have received a copy of the GNU Lesser General Public License 18 * along with this library; if not, write to the Free Software 19 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 20 */ 21#include "fscache.h" 22#include "cifsglob.h" 23#include "cifs_debug.h" 24#include "cifs_fs_sb.h" 25 26void cifs_fscache_get_client_cookie(struct TCP_Server_Info *server) 27{ 28 server->fscache = 29 fscache_acquire_cookie(cifs_fscache_netfs.primary_index, 30 &cifs_fscache_server_index_def, server); 31 cFYI(1, "CIFS: get client cookie (0x%p/0x%p)", server, 32 server->fscache); 33} 34 35void cifs_fscache_release_client_cookie(struct TCP_Server_Info *server) 36{ 37 cFYI(1, "CIFS: release client cookie (0x%p/0x%p)", server, 38 server->fscache); 39 fscache_relinquish_cookie(server->fscache, 0); 40 server->fscache = NULL; 41} 42 43void cifs_fscache_get_super_cookie(struct cifsTconInfo *tcon) 44{ 45 struct TCP_Server_Info *server = tcon->ses->server; 46 47 tcon->fscache = 48 fscache_acquire_cookie(server->fscache, 49 &cifs_fscache_super_index_def, tcon); 50 cFYI(1, "CIFS: get superblock cookie (0x%p/0x%p)", 51 server->fscache, tcon->fscache); 52} 53 54void cifs_fscache_release_super_cookie(struct cifsTconInfo *tcon) 55{ 56 cFYI(1, "CIFS: releasing superblock cookie (0x%p)", tcon->fscache); 57 fscache_relinquish_cookie(tcon->fscache, 0); 58 tcon->fscache = NULL; 59} 60 61static void cifs_fscache_enable_inode_cookie(struct inode *inode) 62{ 63 struct cifsInodeInfo *cifsi = CIFS_I(inode); 64 struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb); 65 66 if (cifsi->fscache) 67 return; 68 69 cifsi->fscache = fscache_acquire_cookie(cifs_sb->tcon->fscache, 70 &cifs_fscache_inode_object_def, 71 cifsi); 72 cFYI(1, "CIFS: got FH cookie (0x%p/0x%p)", 73 cifs_sb->tcon->fscache, cifsi->fscache); 74} 75 76void cifs_fscache_release_inode_cookie(struct inode *inode) 77{ 78 struct cifsInodeInfo *cifsi = CIFS_I(inode); 79 80 if (cifsi->fscache) { 81 cFYI(1, "CIFS releasing inode cookie (0x%p)", 82 cifsi->fscache); 83 fscache_relinquish_cookie(cifsi->fscache, 0); 84 cifsi->fscache = NULL; 85 } 86} 87 88static void cifs_fscache_disable_inode_cookie(struct inode *inode) 89{ 90 struct cifsInodeInfo *cifsi = CIFS_I(inode); 91 92 if (cifsi->fscache) { 93 cFYI(1, "CIFS disabling inode cookie (0x%p)", 94 cifsi->fscache); 95 fscache_relinquish_cookie(cifsi->fscache, 1); 96 cifsi->fscache = NULL; 97 } 98} 99 100void cifs_fscache_set_inode_cookie(struct inode *inode, struct file *filp) 101{ 102 if ((filp->f_flags & O_ACCMODE) != O_RDONLY) 103 cifs_fscache_disable_inode_cookie(inode); 104 else { 105 cifs_fscache_enable_inode_cookie(inode); 106 cFYI(1, "CIFS: fscache inode cookie set"); 107 } 108} 109 110void cifs_fscache_reset_inode_cookie(struct inode *inode) 111{ 112 struct cifsInodeInfo *cifsi = CIFS_I(inode); 113 struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb); 114 struct fscache_cookie *old = cifsi->fscache; 115 116 if (cifsi->fscache) { 117 /* retire the current fscache cache and get a new one */ 118 fscache_relinquish_cookie(cifsi->fscache, 1); 119 120 cifsi->fscache = fscache_acquire_cookie(cifs_sb->tcon->fscache, 121 &cifs_fscache_inode_object_def, 122 cifsi); 123 cFYI(1, "CIFS: new cookie 0x%p oldcookie 0x%p", 124 cifsi->fscache, old); 125 } 126} 127 128int cifs_fscache_release_page(struct page *page, gfp_t gfp) 129{ 130 if (PageFsCache(page)) { 131 struct inode *inode = page->mapping->host; 132 struct cifsInodeInfo *cifsi = CIFS_I(inode); 133 134 cFYI(1, "CIFS: fscache release page (0x%p/0x%p)", 135 page, cifsi->fscache); 136 if (!fscache_maybe_release_page(cifsi->fscache, page, gfp)) 137 return 0; 138 } 139 140 return 1; 141} 142 143static void cifs_readpage_from_fscache_complete(struct page *page, void *ctx, 144 int error) 145{ 146 cFYI(1, "CFS: readpage_from_fscache_complete (0x%p/%d)", 147 page, error); 148 if (!error) 149 SetPageUptodate(page); 150 unlock_page(page); 151} 152 153/* 154 * Retrieve a page from FS-Cache 155 */ 156int __cifs_readpage_from_fscache(struct inode *inode, struct page *page) 157{ 158 int ret; 159 160 cFYI(1, "CIFS: readpage_from_fscache(fsc:%p, p:%p, i:0x%p", 161 CIFS_I(inode)->fscache, page, inode); 162 ret = fscache_read_or_alloc_page(CIFS_I(inode)->fscache, page, 163 cifs_readpage_from_fscache_complete, 164 NULL, 165 GFP_KERNEL); 166 switch (ret) { 167 168 case 0: /* page found in fscache, read submitted */ 169 cFYI(1, "CIFS: readpage_from_fscache: submitted"); 170 return ret; 171 case -ENOBUFS: /* page won't be cached */ 172 case -ENODATA: /* page not in cache */ 173 cFYI(1, "CIFS: readpage_from_fscache %d", ret); 174 return 1; 175 176 default: 177 cERROR(1, "unknown error ret = %d", ret); 178 } 179 return ret; 180} 181 182/* 183 * Retrieve a set of pages from FS-Cache 184 */ 185int __cifs_readpages_from_fscache(struct inode *inode, 186 struct address_space *mapping, 187 struct list_head *pages, 188 unsigned *nr_pages) 189{ 190 int ret; 191 192 cFYI(1, "CIFS: __cifs_readpages_from_fscache (0x%p/%u/0x%p)", 193 CIFS_I(inode)->fscache, *nr_pages, inode); 194 ret = fscache_read_or_alloc_pages(CIFS_I(inode)->fscache, mapping, 195 pages, nr_pages, 196 cifs_readpage_from_fscache_complete, 197 NULL, 198 mapping_gfp_mask(mapping)); 199 switch (ret) { 200 case 0: /* read submitted to the cache for all pages */ 201 cFYI(1, "CIFS: readpages_from_fscache: submitted"); 202 return ret; 203 204 case -ENOBUFS: /* some pages are not cached and can't be */ 205 case -ENODATA: /* some pages are not cached */ 206 cFYI(1, "CIFS: readpages_from_fscache: no page"); 207 return 1; 208 209 default: 210 cFYI(1, "unknown error ret = %d", ret); 211 } 212 213 return ret; 214} 215 216void __cifs_readpage_to_fscache(struct inode *inode, struct page *page) 217{ 218 int ret; 219 220 cFYI(1, "CIFS: readpage_to_fscache(fsc: %p, p: %p, i: %p", 221 CIFS_I(inode)->fscache, page, inode); 222 ret = fscache_write_page(CIFS_I(inode)->fscache, page, GFP_KERNEL); 223 if (ret != 0) 224 fscache_uncache_page(CIFS_I(inode)->fscache, page); 225} 226 227void __cifs_fscache_invalidate_page(struct page *page, struct inode *inode) 228{ 229 struct cifsInodeInfo *cifsi = CIFS_I(inode); 230 struct fscache_cookie *cookie = cifsi->fscache; 231 232 cFYI(1, "CIFS: fscache invalidatepage (0x%p/0x%p)", page, cookie); 233 fscache_wait_on_page_write(cookie, page); 234 fscache_uncache_page(cookie, page); 235} 236