[linux.git] / fs / cifs / fscache.c

/*
 *   fs/cifs/fscache.c - CIFS filesystem cache interface
 *
 *   Copyright (c) 2010 Novell, Inc.
 *   Author(s): Suresh Jayaraman <[email protected]>
 *
 *   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);
	struct cifsTconInfo *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);
		cFYI(1, "CIFS: got FH cookie (0x%p/0x%p)", 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);
}

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);
		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);
}
Commit	Line	Data
488f1d2d SJ	1	/*
	2	* fs/cifs/fscache.c - CIFS filesystem cache interface
	3	*
	4	* Copyright (c) 2010 Novell, Inc.
b81209de	5	* Author(s): Suresh Jayaraman <[email protected]>
488f1d2d SJ	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"
9451a9a5	24	#include "cifs_fs_sb.h"
488f1d2d SJ	25
	26	void 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
	35	void 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
d03382ce SJ	43	void 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
	54	void 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	}
9451a9a5 SJ	60
	61	static 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);
0d424ad0	65	struct cifsTconInfo *tcon = cifs_sb_master_tcon(cifs_sb);
9451a9a5 SJ	66
	67	if (cifsi->fscache)
	68	return;
	69
b81209de SJ	70	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_FSCACHE) {
b81209de SJ	71	cifsi->fscache = fscache_acquire_cookie(tcon->fscache,
0d424ad0	72	&cifs_fscache_inode_object_def, cifsi);
b81209de	73	cFYI(1, "CIFS: got FH cookie (0x%p/0x%p)", tcon->fscache,
0d424ad0	74	cifsi->fscache);
b81209de	75	}
9451a9a5 SJ	76	}
	77
	78	void cifs_fscache_release_inode_cookie(struct inode *inode)
	79	{
	80	struct cifsInodeInfo *cifsi = CIFS_I(inode);
	81
	82	if (cifsi->fscache) {
	83	cFYI(1, "CIFS releasing inode cookie (0x%p)",
	84	cifsi->fscache);
	85	fscache_relinquish_cookie(cifsi->fscache, 0);
	86	cifsi->fscache = NULL;
	87	}
	88	}
	89
	90	static void cifs_fscache_disable_inode_cookie(struct inode *inode)
	91	{
	92	struct cifsInodeInfo *cifsi = CIFS_I(inode);
	93
	94	if (cifsi->fscache) {
	95	cFYI(1, "CIFS disabling inode cookie (0x%p)",
	96	cifsi->fscache);
	97	fscache_relinquish_cookie(cifsi->fscache, 1);
	98	cifsi->fscache = NULL;
	99	}
	100	}
	101
	102	void cifs_fscache_set_inode_cookie(struct inode inode, struct file filp)
	103	{
	104	if ((filp->f_flags & O_ACCMODE) != O_RDONLY)
	105	cifs_fscache_disable_inode_cookie(inode);
b81209de	106	else
9451a9a5	107	cifs_fscache_enable_inode_cookie(inode);
9451a9a5 SJ	108	}
	109
	110	void 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
a6e8a845	120	cifsi->fscache = fscache_acquire_cookie(
0d424ad0	121	cifs_sb_master_tcon(cifs_sb)->fscache,
9451a9a5 SJ	122	&cifs_fscache_inode_object_def,
	123	cifsi);
	124	cFYI(1, "CIFS: new cookie 0x%p oldcookie 0x%p",
	125	cifsi->fscache, old);
	126	}
	127	}
85f2d6b4 SJ	128
	129	int cifs_fscache_release_page(struct page *page, gfp_t gfp)
	130	{
	131	if (PageFsCache(page)) {
	132	struct inode *inode = page->mapping->host;
	133	struct cifsInodeInfo *cifsi = CIFS_I(inode);
	134
	135	cFYI(1, "CIFS: fscache release page (0x%p/0x%p)",
	136	page, cifsi->fscache);
	137	if (!fscache_maybe_release_page(cifsi->fscache, page, gfp))
	138	return 0;
	139	}
	140
	141	return 1;
	142	}
	143
56698236 SJ	144	static void cifs_readpage_from_fscache_complete(struct page page, void ctx,
	145	int error)
	146	{
	147	cFYI(1, "CFS: readpage_from_fscache_complete (0x%p/%d)",
	148	page, error);
	149	if (!error)
	150	SetPageUptodate(page);
	151	unlock_page(page);
	152	}
	153
	154	/*
	155	* Retrieve a page from FS-Cache
	156	*/
	157	int __cifs_readpage_from_fscache(struct inode inode, struct page page)
	158	{
	159	int ret;
	160
	161	cFYI(1, "CIFS: readpage_from_fscache(fsc:%p, p:%p, i:0x%p",
	162	CIFS_I(inode)->fscache, page, inode);
	163	ret = fscache_read_or_alloc_page(CIFS_I(inode)->fscache, page,
	164	cifs_readpage_from_fscache_complete,
	165	NULL,
	166	GFP_KERNEL);
	167	switch (ret) {
	168
	169	case 0: /* page found in fscache, read submitted */
	170	cFYI(1, "CIFS: readpage_from_fscache: submitted");
	171	return ret;
	172	case -ENOBUFS: /* page won't be cached */
	173	case -ENODATA: /* page not in cache */
	174	cFYI(1, "CIFS: readpage_from_fscache %d", ret);
	175	return 1;
	176
	177	default:
	178	cERROR(1, "unknown error ret = %d", ret);
	179	}
	180	return ret;
	181	}
	182
	183	/*
	184	* Retrieve a set of pages from FS-Cache
	185	*/
	186	int __cifs_readpages_from_fscache(struct inode *inode,
	187	struct address_space *mapping,
	188	struct list_head *pages,
	189	unsigned *nr_pages)
	190	{
	191	int ret;
	192
	193	cFYI(1, "CIFS: __cifs_readpages_from_fscache (0x%p/%u/0x%p)",
	194	CIFS_I(inode)->fscache, *nr_pages, inode);
	195	ret = fscache_read_or_alloc_pages(CIFS_I(inode)->fscache, mapping,
	196	pages, nr_pages,
	197	cifs_readpage_from_fscache_complete,
	198	NULL,
	199	mapping_gfp_mask(mapping));
	200	switch (ret) {
	201	case 0: /* read submitted to the cache for all pages */
	202	cFYI(1, "CIFS: readpages_from_fscache: submitted");
	203	return ret;
	204
	205	case -ENOBUFS: /* some pages are not cached and can't be */
	206	case -ENODATA: /* some pages are not cached */
	207	cFYI(1, "CIFS: readpages_from_fscache: no page");
208	return 1;
209
210	default:
211	cFYI(1, "unknown error ret = %d", ret);
212	}
213
214	return ret;
215	}
216
9dc06558 SJ	217	void __cifs_readpage_to_fscache(struct inode inode, struct page page)
	218	{
	219	int ret;
	220
	221	cFYI(1, "CIFS: readpage_to_fscache(fsc: %p, p: %p, i: %p",
	222	CIFS_I(inode)->fscache, page, inode);
	223	ret = fscache_write_page(CIFS_I(inode)->fscache, page, GFP_KERNEL);
	224	if (ret != 0)
	225	fscache_uncache_page(CIFS_I(inode)->fscache, page);
	226	}
	227
85f2d6b4 SJ	228	void __cifs_fscache_invalidate_page(struct page page, struct inode inode)
	229	{
	230	struct cifsInodeInfo *cifsi = CIFS_I(inode);
	231	struct fscache_cookie *cookie = cifsi->fscache;
	232
	233	cFYI(1, "CIFS: fscache invalidatepage (0x%p/0x%p)", page, cookie);
	234	fscache_wait_on_page_write(cookie, page);
	235	fscache_uncache_page(cookie, page);
	236	}
	237