diff options
Diffstat (limited to 'fs/cifs/fscache.c')
| -rw-r--r-- | fs/cifs/fscache.c | 334 |
1 files changed, 334 insertions, 0 deletions
diff --git a/fs/cifs/fscache.c b/fs/cifs/fscache.c new file mode 100644 index 000000000..ea6ace9c2 --- /dev/null +++ b/fs/cifs/fscache.c @@ -0,0 +1,334 @@ +/* + * 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" + +/* + * Key layout of CIFS server cache index object + */ +struct cifs_server_key { + struct { + uint16_t family; /* address family */ + __be16 port; /* IP port */ + } hdr; + union { + struct in_addr ipv4_addr; + struct in6_addr ipv6_addr; + }; +} __packed; + +/* + * Get a cookie for a server object keyed by {IPaddress,port,family} tuple + */ +void cifs_fscache_get_client_cookie(struct TCP_Server_Info *server) +{ + const struct sockaddr *sa = (struct sockaddr *) &server->dstaddr; + const struct sockaddr_in *addr = (struct sockaddr_in *) sa; + const struct sockaddr_in6 *addr6 = (struct sockaddr_in6 *) sa; + struct cifs_server_key key; + uint16_t key_len = sizeof(key.hdr); + + memset(&key, 0, sizeof(key)); + + /* + * Should not be a problem as sin_family/sin6_family overlays + * sa_family field + */ + key.hdr.family = sa->sa_family; + switch (sa->sa_family) { + case AF_INET: + key.hdr.port = addr->sin_port; + key.ipv4_addr = addr->sin_addr; + key_len += sizeof(key.ipv4_addr); + break; + + case AF_INET6: + key.hdr.port = addr6->sin6_port; + key.ipv6_addr = addr6->sin6_addr; + key_len += sizeof(key.ipv6_addr); + break; + + default: + cifs_dbg(VFS, "Unknown network family '%d'\n", sa->sa_family); + server->fscache = NULL; + return; + } + + server->fscache = + fscache_acquire_cookie(cifs_fscache_netfs.primary_index, + &cifs_fscache_server_index_def, + &key, key_len, + NULL, 0, + server, 0, 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, NULL, false); + server->fscache = NULL; +} + +void cifs_fscache_get_super_cookie(struct cifs_tcon *tcon) +{ + struct TCP_Server_Info *server = tcon->ses->server; + char *sharename; + + sharename = extract_sharename(tcon->treeName); + if (IS_ERR(sharename)) { + cifs_dbg(FYI, "%s: couldn't extract sharename\n", __func__); + tcon->fscache = NULL; + return; + } + + tcon->fscache = + fscache_acquire_cookie(server->fscache, + &cifs_fscache_super_index_def, + sharename, strlen(sharename), + &tcon->resource_id, sizeof(tcon->resource_id), + tcon, 0, true); + kfree(sharename); + 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, &tcon->resource_id, false); + tcon->fscache = NULL; +} + +static void cifs_fscache_acquire_inode_cookie(struct cifsInodeInfo *cifsi, + struct cifs_tcon *tcon) +{ + struct cifs_fscache_inode_auxdata auxdata; + + memset(&auxdata, 0, sizeof(auxdata)); + auxdata.eof = cifsi->server_eof; + auxdata.last_write_time_sec = cifsi->vfs_inode.i_mtime.tv_sec; + auxdata.last_change_time_sec = cifsi->vfs_inode.i_ctime.tv_sec; + auxdata.last_write_time_nsec = cifsi->vfs_inode.i_mtime.tv_nsec; + auxdata.last_change_time_nsec = cifsi->vfs_inode.i_ctime.tv_nsec; + + cifsi->fscache = + fscache_acquire_cookie(tcon->fscache, + &cifs_fscache_inode_object_def, + &cifsi->uniqueid, sizeof(cifsi->uniqueid), + &auxdata, sizeof(auxdata), + cifsi, cifsi->vfs_inode.i_size, true); +} + +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)) + return; + + cifs_fscache_acquire_inode_cookie(cifsi, tcon); + + 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 cifs_fscache_inode_auxdata auxdata; + struct cifsInodeInfo *cifsi = CIFS_I(inode); + + if (cifsi->fscache) { + memset(&auxdata, 0, sizeof(auxdata)); + auxdata.eof = cifsi->server_eof; + auxdata.last_write_time_sec = cifsi->vfs_inode.i_mtime.tv_sec; + auxdata.last_change_time_sec = cifsi->vfs_inode.i_ctime.tv_sec; + auxdata.last_write_time_nsec = cifsi->vfs_inode.i_mtime.tv_nsec; + auxdata.last_change_time_nsec = cifsi->vfs_inode.i_ctime.tv_nsec; + + cifs_dbg(FYI, "%s: (0x%p)\n", __func__, cifsi->fscache); + fscache_relinquish_cookie(cifsi->fscache, &auxdata, false); + 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, NULL, true); + 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 cifs_tcon *tcon = cifs_sb_master_tcon(cifs_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, NULL, true); + + cifs_fscache_acquire_inode_cookie(cifsi, tcon); + 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) +{ + struct cifsInodeInfo *cifsi = CIFS_I(inode); + int ret; + + cifs_dbg(FYI, "%s: (fsc: %p, p: %p, i: %p)\n", + __func__, cifsi->fscache, page, inode); + ret = fscache_write_page(cifsi->fscache, page, + cifsi->vfs_inode.i_size, GFP_KERNEL); + if (ret != 0) + fscache_uncache_page(cifsi->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); +} |