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

/*
 *   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, "%s: (0x%p/0x%p)", __func__, server,
			server->fscache);
}

void cifs_fscache_release_client_cookie(struct TCP_Server_Info *server)
{
	cFYI(1, "%s: (0x%p/0x%p)", __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);
	cFYI(1, "%s: (0x%p/0x%p)", __func__, server->fscache,
			tcon->fscache);
}

void cifs_fscache_release_super_cookie(struct cifs_tcon *tcon)
{
	cFYI(1, "%s: (0x%p)", __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);
		cFYI(1, "%s: got FH cookie (0x%p/0x%p)", __func__,
				tcon->fscache, cifsi->fscache);
	}
}

void cifs_fscache_release_inode_cookie(struct inode *inode)
{
	struct cifsInodeInfo *cifsi = CIFS_I(inode);

	if (cifsi->fscache) {
		cFYI(1, "%s: (0x%p)", __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) {
		cFYI(1, "%s: (0x%p)", __func__, 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, "%s: new cookie 0x%p oldcookie 0x%p",
				__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);

		cFYI(1, "%s: (0x%p/0x%p)", __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)
{
	cFYI(1, "%s: (0x%p/%d)", __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;

	cFYI(1, "%s: (fsc:%p, p:%p, i:0x%p", __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 */
		cFYI(1, "%s: submitted", __func__);
		return ret;
	case -ENOBUFS:	/* page won't be cached */
	case -ENODATA:	/* page not in cache */
		cFYI(1, "%s: %d", __func__, 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, "%s: (0x%p/%u/0x%p)", __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 */
		cFYI(1, "%s: submitted", __func__);
		return ret;

	case -ENOBUFS:	/* some pages are not cached and can't be */
	case -ENODATA:	/* some pages are not cached */
		cFYI(1, "%s: no page", __func__);
		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, "%s: (fsc: %p, p: %p, i: %p)", __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_invalidate_page(struct page *page, struct inode *inode)
{
	struct cifsInodeInfo *cifsi = CIFS_I(inode);
	struct fscache_cookie *cookie = cifsi->fscache;

	cFYI(1, "%s: (0x%p/0x%p)", __func__, 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 <sjayaraman@suse.de>
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);
040d15c8 SF	31	cFYI(1, "%s: (0x%p/0x%p)", __func__, server,
040d15c8 SF	32	server->fscache);
488f1d2d SJ	33	}
	34
	35	void cifs_fscache_release_client_cookie(struct TCP_Server_Info *server)
	36	{
040d15c8 SF	37	cFYI(1, "%s: (0x%p/0x%p)", __func__, server,
040d15c8 SF	38	server->fscache);
488f1d2d SJ	39	fscache_relinquish_cookie(server->fscache, 0);
	40	server->fscache = NULL;
	41	}
	42
96daf2b0	43	void cifs_fscache_get_super_cookie(struct cifs_tcon *tcon)
d03382ce SJ	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);
040d15c8 SF	50	cFYI(1, "%s: (0x%p/0x%p)", __func__, server->fscache,
040d15c8 SF	51	tcon->fscache);
d03382ce SJ	52	}
d03382ce SJ	53
96daf2b0	54	void cifs_fscache_release_super_cookie(struct cifs_tcon *tcon)
d03382ce	55	{
040d15c8	56	cFYI(1, "%s: (0x%p)", __func__, tcon->fscache);
d03382ce SJ	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);
96daf2b0	65	struct cifs_tcon *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);
040d15c8 SF	73	cFYI(1, "%s: got FH cookie (0x%p/0x%p)", __func__,
040d15c8 SF	74	tcon->fscache, 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) {
040d15c8	83	cFYI(1, "%s: (0x%p)", __func__, cifsi->fscache);
9451a9a5 SJ	84	fscache_relinquish_cookie(cifsi->fscache, 0);
	85	cifsi->fscache = NULL;
	86	}
	87	}
	88
	89	static void cifs_fscache_disable_inode_cookie(struct inode *inode)
	90	{
	91	struct cifsInodeInfo *cifsi = CIFS_I(inode);
	92
	93	if (cifsi->fscache) {
040d15c8	94	cFYI(1, "%s: (0x%p)", __func__, cifsi->fscache);
9451a9a5 SJ	95	fscache_relinquish_cookie(cifsi->fscache, 1);
	96	cifsi->fscache = NULL;
	97	}
	98	}
	99
	100	void 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);
b81209de	104	else
9451a9a5	105	cifs_fscache_enable_inode_cookie(inode);
9451a9a5 SJ	106	}
	107
	108	void cifs_fscache_reset_inode_cookie(struct inode *inode)
	109	{
	110	struct cifsInodeInfo *cifsi = CIFS_I(inode);
	111	struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
	112	struct fscache_cookie *old = cifsi->fscache;
	113
	114	if (cifsi->fscache) {
	115	/* retire the current fscache cache and get a new one */
	116	fscache_relinquish_cookie(cifsi->fscache, 1);
	117
a6e8a845	118	cifsi->fscache = fscache_acquire_cookie(
0d424ad0	119	cifs_sb_master_tcon(cifs_sb)->fscache,
9451a9a5 SJ	120	&cifs_fscache_inode_object_def,
9451a9a5 SJ	121	cifsi);
040d15c8 SF	122	cFYI(1, "%s: new cookie 0x%p oldcookie 0x%p",
040d15c8 SF	123	__func__, cifsi->fscache, old);
9451a9a5 SJ	124	}
9451a9a5 SJ	125	}
85f2d6b4 SJ	126
	127	int cifs_fscache_release_page(struct page *page, gfp_t gfp)
	128	{
	129	if (PageFsCache(page)) {
	130	struct inode *inode = page->mapping->host;
	131	struct cifsInodeInfo *cifsi = CIFS_I(inode);
	132
040d15c8 SF	133	cFYI(1, "%s: (0x%p/0x%p)", __func__, page,
040d15c8 SF	134	cifsi->fscache);
85f2d6b4 SJ	135	if (!fscache_maybe_release_page(cifsi->fscache, page, gfp))
	136	return 0;
	137	}
	138
	139	return 1;
	140	}
	141
56698236 SJ	142	static void cifs_readpage_from_fscache_complete(struct page page, void ctx,
	143	int error)
	144	{
040d15c8	145	cFYI(1, "%s: (0x%p/%d)", __func__, page, error);
56698236 SJ	146	if (!error)
	147	SetPageUptodate(page);
	148	unlock_page(page);
	149	}
	150
	151	/*
	152	* Retrieve a page from FS-Cache
	153	*/
	154	int __cifs_readpage_from_fscache(struct inode inode, struct page page)
	155	{
	156	int ret;
	157
040d15c8	158	cFYI(1, "%s: (fsc:%p, p:%p, i:0x%p", __func__,
56698236 SJ	159	CIFS_I(inode)->fscache, page, inode);
	160	ret = fscache_read_or_alloc_page(CIFS_I(inode)->fscache, page,
	161	cifs_readpage_from_fscache_complete,
	162	NULL,
	163	GFP_KERNEL);
	164	switch (ret) {
	165
	166	case 0: /* page found in fscache, read submitted */
040d15c8	167	cFYI(1, "%s: submitted", __func__);
56698236 SJ	168	return ret;
	169	case -ENOBUFS: /* page won't be cached */
	170	case -ENODATA: /* page not in cache */
040d15c8	171	cFYI(1, "%s: %d", __func__, ret);
56698236 SJ	172	return 1;
	173
	174	default:
	175	cERROR(1, "unknown error ret = %d", ret);
	176	}
	177	return ret;
	178	}
	179
	180	/*
	181	* Retrieve a set of pages from FS-Cache
	182	*/
	183	int __cifs_readpages_from_fscache(struct inode *inode,
	184	struct address_space *mapping,
	185	struct list_head *pages,
	186	unsigned *nr_pages)
	187	{
	188	int ret;
	189
040d15c8	190	cFYI(1, "%s: (0x%p/%u/0x%p)", __func__,
56698236 SJ	191	CIFS_I(inode)->fscache, *nr_pages, inode);
	192	ret = fscache_read_or_alloc_pages(CIFS_I(inode)->fscache, mapping,
	193	pages, nr_pages,
	194	cifs_readpage_from_fscache_complete,
	195	NULL,
	196	mapping_gfp_mask(mapping));
	197	switch (ret) {
	198	case 0: /* read submitted to the cache for all pages */
040d15c8	199	cFYI(1, "%s: submitted", __func__);
56698236 SJ	200	return ret;
	201
	202	case -ENOBUFS: /* some pages are not cached and can't be */
	203	case -ENODATA: /* some pages are not cached */
040d15c8	204	cFYI(1, "%s: no page", __func__);
56698236 SJ	205	return 1;
	206
	207	default:
	208	cFYI(1, "unknown error ret = %d", ret);
	209	}
	210
	211	return ret;
	212	}
	213
9dc06558 SJ	214	void __cifs_readpage_to_fscache(struct inode inode, struct page page)
	215	{
	216	int ret;
	217
040d15c8	218	cFYI(1, "%s: (fsc: %p, p: %p, i: %p)", __func__,
9dc06558 SJ	219	CIFS_I(inode)->fscache, page, inode);
	220	ret = fscache_write_page(CIFS_I(inode)->fscache, page, GFP_KERNEL);
	221	if (ret != 0)
	222	fscache_uncache_page(CIFS_I(inode)->fscache, page);
	223	}
	224
85f2d6b4 SJ	225	void __cifs_fscache_invalidate_page(struct page page, struct inode inode)
	226	{
	227	struct cifsInodeInfo *cifsi = CIFS_I(inode);
	228	struct fscache_cookie *cookie = cifsi->fscache;
	229
040d15c8	230	cFYI(1, "%s: (0x%p/0x%p)", __func__, page, cookie);
85f2d6b4 SJ	231	fscache_wait_on_page_write(cookie, page);
	232	fscache_uncache_page(cookie, page);
	233	}
	234