fs/cifs/fscache.c - linux - Git at Google

 // SPDX-License-Identifier: LGPL-2.1
 /*
  *   fs/cifs/fscache.c - CIFS filesystem cache interface
  *
  *   Copyright (c) 2010 Novell, Inc.
  *   Author(s): Suresh Jayaraman <sjayaraman@suse.de>
  *
  */
 #include "fscache.h"
 #include "cifsglob.h"
 #include "cifs_debug.h"
 #include "cifs_fs_sb.h"
 #include "cifsproto.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;
 	struct cifs_fscache_super_auxdata auxdata;

 	sharename = extract_sharename(tcon->treeName);
 	if (IS_ERR(sharename)) {
 		cifs_dbg(FYI, "%s: couldn't extract sharename\n", __func__);
 		tcon->fscache = NULL;
 		return;
 	}

 	memset(&auxdata, 0, sizeof(auxdata));
 	auxdata.resource_id = tcon->resource_id;
 	auxdata.vol_create_time = tcon->vol_create_time;
 	auxdata.vol_serial_number = tcon->vol_serial_number;

 	tcon->fscache =
 		fscache_acquire_cookie(server->fscache,
 				       &cifs_fscache_super_index_def,
 				       sharename, strlen(sharename),
 				       &auxdata, sizeof(auxdata),
 				       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)
 {
 	struct cifs_fscache_super_auxdata auxdata;

 	memset(&auxdata, 0, sizeof(auxdata));
 	auxdata.resource_id = tcon->resource_id;
 	auxdata.vol_create_time = tcon->vol_create_time;
 	auxdata.vol_serial_number = tcon->vol_serial_number;

 	cifs_dbg(FYI, "%s: (0x%p)\n", __func__, tcon->fscache);
 	fscache_relinquish_cookie(tcon->fscache, &auxdata, 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 does not seem to update auxdata */
 		fscache_update_cookie(cifsi->fscache, &auxdata);
 		fscache_relinquish_cookie(cifsi->fscache, &auxdata, false);
 		cifsi->fscache = NULL;
 	}
 }

 void cifs_fscache_update_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_update_cookie(cifsi->fscache, &auxdata);
 	}
 }

 void cifs_fscache_set_inode_cookie(struct inode *inode, struct file *filp)
 {
 	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;

 	WARN_ON(!cifsi->fscache);

 	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);
 }

 void __cifs_fscache_wait_on_page_write(struct inode *inode, struct page *page)
 {
 	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);
 }

 void __cifs_fscache_uncache_page(struct inode *inode, struct page *page)
 {
 	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_uncache_page(cookie, page);
 }
	// SPDX-License-Identifier: LGPL-2.1
	/*
	* fs/cifs/fscache.c - CIFS filesystem cache interface
	*
	* Copyright (c) 2010 Novell, Inc.
	* Author(s): Suresh Jayaraman <sjayaraman@suse.de>
	*
	*/
	#include "fscache.h"
	#include "cifsglob.h"
	#include "cifs_debug.h"
	#include "cifs_fs_sb.h"
	#include "cifsproto.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;
	struct cifs_fscache_super_auxdata auxdata;

	sharename = extract_sharename(tcon->treeName);
	if (IS_ERR(sharename)) {
	cifs_dbg(FYI, "%s: couldn't extract sharename\n", __func__);
	tcon->fscache = NULL;
	return;
	}

	memset(&auxdata, 0, sizeof(auxdata));
	auxdata.resource_id = tcon->resource_id;
	auxdata.vol_create_time = tcon->vol_create_time;
	auxdata.vol_serial_number = tcon->vol_serial_number;

	tcon->fscache =
	fscache_acquire_cookie(server->fscache,
	&cifs_fscache_super_index_def,
	sharename, strlen(sharename),
	&auxdata, sizeof(auxdata),
	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)
	{
	struct cifs_fscache_super_auxdata auxdata;

	memset(&auxdata, 0, sizeof(auxdata));
	auxdata.resource_id = tcon->resource_id;
	auxdata.vol_create_time = tcon->vol_create_time;
	auxdata.vol_serial_number = tcon->vol_serial_number;

	cifs_dbg(FYI, "%s: (0x%p)\n", __func__, tcon->fscache);
	fscache_relinquish_cookie(tcon->fscache, &auxdata, 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 does not seem to update auxdata */
	fscache_update_cookie(cifsi->fscache, &auxdata);
	fscache_relinquish_cookie(cifsi->fscache, &auxdata, false);
	cifsi->fscache = NULL;
	}
	}

	void cifs_fscache_update_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_update_cookie(cifsi->fscache, &auxdata);
	}
	}

	void cifs_fscache_set_inode_cookie(struct inode inode, struct file filp)
	{
	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;

	WARN_ON(!cifsi->fscache);

	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);
	}

	void __cifs_fscache_wait_on_page_write(struct inode inode, struct page page)
	{
	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);
	}

	void __cifs_fscache_uncache_page(struct inode inode, struct page page)
	{
	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_uncache_page(cookie, page);
	}