diff options
Diffstat (limited to 'kernel/fs/cifs/fscache.c')
| -rw-r--r-- | kernel/fs/cifs/fscache.c | 242 |
1 files changed, 242 insertions, 0 deletions
diff --git a/kernel/fs/cifs/fscache.c b/kernel/fs/cifs/fscache.c new file mode 100644 index 000000000..8d4b7bc8a --- /dev/null +++ b/kernel/fs/cifs/fscache.c @@ -0,0 +1,242 @@ +/* + * fs/cifs/fscache.c - CIFS filesystem cache interface + * + * Copyright (c) 2010 Novell, Inc. + * Author(s): Suresh Jayaraman <sjayaraman@suse.de> + * + * This library is free software; you can redistribute it and/or modify + * it under the terms of the GNU Lesser General Public License as published + * by the Free Software Foundation; either version 2.1 of the License, or + * (at your option) any later version. + * + * This library is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See + * the GNU Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public License + * along with this library; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ +#include "fscache.h" +#include "cifsglob.h" +#include "cifs_debug.h" +#include "cifs_fs_sb.h" + +void cifs_fscache_get_client_cookie(struct TCP_Server_Info *server) +{ + server->fscache = + fscache_acquire_cookie(cifs_fscache_netfs.primary_index, + &cifs_fscache_server_index_def, server, true); + cifs_dbg(FYI, "%s: (0x%p/0x%p)\n", + __func__, server, server->fscache); +} + +void cifs_fscache_release_client_cookie(struct TCP_Server_Info *server) +{ + cifs_dbg(FYI, "%s: (0x%p/0x%p)\n", + __func__, server, server->fscache); + fscache_relinquish_cookie(server->fscache, 0); + server->fscache = NULL; +} + +void cifs_fscache_get_super_cookie(struct cifs_tcon *tcon) +{ + struct TCP_Server_Info *server = tcon->ses->server; + + tcon->fscache = + fscache_acquire_cookie(server->fscache, + &cifs_fscache_super_index_def, tcon, true); + cifs_dbg(FYI, "%s: (0x%p/0x%p)\n", + __func__, server->fscache, tcon->fscache); +} + +void cifs_fscache_release_super_cookie(struct cifs_tcon *tcon) +{ + cifs_dbg(FYI, "%s: (0x%p)\n", __func__, tcon->fscache); + fscache_relinquish_cookie(tcon->fscache, 0); + tcon->fscache = NULL; +} + +static void cifs_fscache_enable_inode_cookie(struct inode *inode) +{ + struct cifsInodeInfo *cifsi = CIFS_I(inode); + struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb); + struct cifs_tcon *tcon = cifs_sb_master_tcon(cifs_sb); + + if (cifsi->fscache) + return; + + if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_FSCACHE) { + cifsi->fscache = fscache_acquire_cookie(tcon->fscache, + &cifs_fscache_inode_object_def, cifsi, true); + cifs_dbg(FYI, "%s: got FH cookie (0x%p/0x%p)\n", + __func__, tcon->fscache, cifsi->fscache); + } +} + +void cifs_fscache_release_inode_cookie(struct inode *inode) +{ + struct cifsInodeInfo *cifsi = CIFS_I(inode); + + if (cifsi->fscache) { + cifs_dbg(FYI, "%s: (0x%p)\n", __func__, cifsi->fscache); + fscache_relinquish_cookie(cifsi->fscache, 0); + cifsi->fscache = NULL; + } +} + +static void cifs_fscache_disable_inode_cookie(struct inode *inode) +{ + struct cifsInodeInfo *cifsi = CIFS_I(inode); + + if (cifsi->fscache) { + cifs_dbg(FYI, "%s: (0x%p)\n", __func__, cifsi->fscache); + fscache_uncache_all_inode_pages(cifsi->fscache, inode); + fscache_relinquish_cookie(cifsi->fscache, 1); + cifsi->fscache = NULL; + } +} + +void cifs_fscache_set_inode_cookie(struct inode *inode, struct file *filp) +{ + if ((filp->f_flags & O_ACCMODE) != O_RDONLY) + cifs_fscache_disable_inode_cookie(inode); + else + cifs_fscache_enable_inode_cookie(inode); +} + +void cifs_fscache_reset_inode_cookie(struct inode *inode) +{ + struct cifsInodeInfo *cifsi = CIFS_I(inode); + struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb); + struct fscache_cookie *old = cifsi->fscache; + + if (cifsi->fscache) { + /* retire the current fscache cache and get a new one */ + fscache_relinquish_cookie(cifsi->fscache, 1); + + cifsi->fscache = fscache_acquire_cookie( + cifs_sb_master_tcon(cifs_sb)->fscache, + &cifs_fscache_inode_object_def, + cifsi, true); + cifs_dbg(FYI, "%s: new cookie 0x%p oldcookie 0x%p\n", + __func__, cifsi->fscache, old); + } +} + +int cifs_fscache_release_page(struct page *page, gfp_t gfp) +{ + if (PageFsCache(page)) { + struct inode *inode = page->mapping->host; + struct cifsInodeInfo *cifsi = CIFS_I(inode); + + cifs_dbg(FYI, "%s: (0x%p/0x%p)\n", + __func__, page, cifsi->fscache); + if (!fscache_maybe_release_page(cifsi->fscache, page, gfp)) + return 0; + } + + return 1; +} + +static void cifs_readpage_from_fscache_complete(struct page *page, void *ctx, + int error) +{ + cifs_dbg(FYI, "%s: (0x%p/%d)\n", __func__, page, error); + if (!error) + SetPageUptodate(page); + unlock_page(page); +} + +/* + * Retrieve a page from FS-Cache + */ +int __cifs_readpage_from_fscache(struct inode *inode, struct page *page) +{ + int ret; + + cifs_dbg(FYI, "%s: (fsc:%p, p:%p, i:0x%p\n", + __func__, CIFS_I(inode)->fscache, page, inode); + ret = fscache_read_or_alloc_page(CIFS_I(inode)->fscache, page, + cifs_readpage_from_fscache_complete, + NULL, + GFP_KERNEL); + switch (ret) { + + case 0: /* page found in fscache, read submitted */ + cifs_dbg(FYI, "%s: submitted\n", __func__); + return ret; + case -ENOBUFS: /* page won't be cached */ + case -ENODATA: /* page not in cache */ + cifs_dbg(FYI, "%s: %d\n", __func__, ret); + return 1; + + default: + cifs_dbg(VFS, "unknown error ret = %d\n", ret); + } + return ret; +} + +/* + * Retrieve a set of pages from FS-Cache + */ +int __cifs_readpages_from_fscache(struct inode *inode, + struct address_space *mapping, + struct list_head *pages, + unsigned *nr_pages) +{ + int ret; + + cifs_dbg(FYI, "%s: (0x%p/%u/0x%p)\n", + __func__, CIFS_I(inode)->fscache, *nr_pages, inode); + ret = fscache_read_or_alloc_pages(CIFS_I(inode)->fscache, mapping, + pages, nr_pages, + cifs_readpage_from_fscache_complete, + NULL, + mapping_gfp_mask(mapping)); + switch (ret) { + case 0: /* read submitted to the cache for all pages */ + cifs_dbg(FYI, "%s: submitted\n", __func__); + return ret; + + case -ENOBUFS: /* some pages are not cached and can't be */ + case -ENODATA: /* some pages are not cached */ + cifs_dbg(FYI, "%s: no page\n", __func__); + return 1; + + default: + cifs_dbg(FYI, "unknown error ret = %d\n", ret); + } + + return ret; +} + +void __cifs_readpage_to_fscache(struct inode *inode, struct page *page) +{ + int ret; + + cifs_dbg(FYI, "%s: (fsc: %p, p: %p, i: %p)\n", + __func__, CIFS_I(inode)->fscache, page, inode); + ret = fscache_write_page(CIFS_I(inode)->fscache, page, GFP_KERNEL); + if (ret != 0) + fscache_uncache_page(CIFS_I(inode)->fscache, page); +} + +void __cifs_fscache_readpages_cancel(struct inode *inode, struct list_head *pages) +{ + cifs_dbg(FYI, "%s: (fsc: %p, i: %p)\n", + __func__, CIFS_I(inode)->fscache, inode); + fscache_readpages_cancel(CIFS_I(inode)->fscache, pages); +} + +void __cifs_fscache_invalidate_page(struct page *page, struct inode *inode) +{ + struct cifsInodeInfo *cifsi = CIFS_I(inode); + struct fscache_cookie *cookie = cifsi->fscache; + + cifs_dbg(FYI, "%s: (0x%p/0x%p)\n", __func__, page, cookie); + fscache_wait_on_page_write(cookie, page); + fscache_uncache_page(cookie, page); +} + |