diff options
Diffstat (limited to 'fs/cifs/fscache.c')
| -rw-r--r-- | fs/cifs/fscache.c | 236 | 
1 files changed, 236 insertions, 0 deletions
diff --git a/fs/cifs/fscache.c b/fs/cifs/fscache.c new file mode 100644 index 00000000000..9f3f5c4be16 --- /dev/null +++ b/fs/cifs/fscache.c @@ -0,0 +1,236 @@ +/* + *   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); +	cFYI(1, "CIFS: get client cookie (0x%p/0x%p)", server, +				server->fscache); +} + +void cifs_fscache_release_client_cookie(struct TCP_Server_Info *server) +{ +	cFYI(1, "CIFS: release client cookie (0x%p/0x%p)", server, +				server->fscache); +	fscache_relinquish_cookie(server->fscache, 0); +	server->fscache = NULL; +} + +void cifs_fscache_get_super_cookie(struct cifsTconInfo *tcon) +{ +	struct TCP_Server_Info *server = tcon->ses->server; + +	tcon->fscache = +		fscache_acquire_cookie(server->fscache, +				&cifs_fscache_super_index_def, tcon); +	cFYI(1, "CIFS: get superblock cookie (0x%p/0x%p)", +				server->fscache, tcon->fscache); +} + +void cifs_fscache_release_super_cookie(struct cifsTconInfo *tcon) +{ +	cFYI(1, "CIFS: releasing superblock cookie (0x%p)", 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); + +	if (cifsi->fscache) +		return; + +	cifsi->fscache = fscache_acquire_cookie(cifs_sb->tcon->fscache, +				&cifs_fscache_inode_object_def, +				cifsi); +	cFYI(1, "CIFS: got FH cookie (0x%p/0x%p)", +			cifs_sb->tcon->fscache, cifsi->fscache); +} + +void cifs_fscache_release_inode_cookie(struct inode *inode) +{ +	struct cifsInodeInfo *cifsi = CIFS_I(inode); + +	if (cifsi->fscache) { +		cFYI(1, "CIFS releasing inode cookie (0x%p)", +				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) { +		cFYI(1, "CIFS disabling inode cookie (0x%p)", +				cifsi->fscache); +		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); +		cFYI(1, "CIFS: fscache inode cookie set"); +	} +} + +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->tcon->fscache, +					&cifs_fscache_inode_object_def, +					cifsi); +		cFYI(1, "CIFS: new cookie 0x%p oldcookie 0x%p", +				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); + +		cFYI(1, "CIFS: fscache release page (0x%p/0x%p)", +				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) +{ +	cFYI(1, "CFS: readpage_from_fscache_complete (0x%p/%d)", +			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; + +	cFYI(1, "CIFS: readpage_from_fscache(fsc:%p, p:%p, i:0x%p", +			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 */ +		cFYI(1, "CIFS: readpage_from_fscache: submitted"); +		return ret; +	case -ENOBUFS:	/* page won't be cached */ +	case -ENODATA:	/* page not in cache */ +		cFYI(1, "CIFS: readpage_from_fscache %d", ret); +		return 1; + +	default: +		cERROR(1, "unknown error ret = %d", 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; + +	cFYI(1, "CIFS: __cifs_readpages_from_fscache (0x%p/%u/0x%p)", +			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 */ +		cFYI(1, "CIFS: readpages_from_fscache: submitted"); +		return ret; + +	case -ENOBUFS:	/* some pages are not cached and can't be */ +	case -ENODATA:	/* some pages are not cached */ +		cFYI(1, "CIFS: readpages_from_fscache: no page"); +		return 1; + +	default: +		cFYI(1, "unknown error ret = %d", ret); +	} + +	return ret; +} + +void __cifs_readpage_to_fscache(struct inode *inode, struct page *page) +{ +	int ret; + +	cFYI(1, "CIFS: readpage_to_fscache(fsc: %p, p: %p, i: %p", +			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_invalidate_page(struct page *page, struct inode *inode) +{ +	struct cifsInodeInfo *cifsi = CIFS_I(inode); +	struct fscache_cookie *cookie = cifsi->fscache; + +	cFYI(1, "CIFS: fscache invalidatepage (0x%p/0x%p)", page, cookie); +	fscache_wait_on_page_write(cookie, page); +	fscache_uncache_page(cookie, page); +} +  |