file.c 64.5 KB
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/*
 *   fs/cifs/file.c
 *
 *   vfs operations that deal with files
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 *
 *   Copyright (C) International Business Machines  Corp., 2002,2007
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 *   Author(s): Steve French (sfrench@us.ibm.com)
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Jeremy Allison 已提交
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 *              Jeremy Allison (jra@samba.org)
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 *
 *   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 <linux/fs.h>
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#include <linux/backing-dev.h>
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#include <linux/stat.h>
#include <linux/fcntl.h>
#include <linux/pagemap.h>
#include <linux/pagevec.h>
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#include <linux/writeback.h>
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#include <linux/task_io_accounting_ops.h>
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#include <linux/delay.h>
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#include <linux/mount.h>
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#include <asm/div64.h>
#include "cifsfs.h"
#include "cifspdu.h"
#include "cifsglob.h"
#include "cifsproto.h"
#include "cifs_unicode.h"
#include "cifs_debug.h"
#include "cifs_fs_sb.h"

static inline int cifs_convert_flags(unsigned int flags)
{
	if ((flags & O_ACCMODE) == O_RDONLY)
		return GENERIC_READ;
	else if ((flags & O_ACCMODE) == O_WRONLY)
		return GENERIC_WRITE;
	else if ((flags & O_ACCMODE) == O_RDWR) {
		/* GENERIC_ALL is too much permission to request
		   can cause unnecessary access denied on create */
		/* return GENERIC_ALL; */
		return (GENERIC_READ | GENERIC_WRITE);
	}

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	return (READ_CONTROL | FILE_WRITE_ATTRIBUTES | FILE_READ_ATTRIBUTES |
		FILE_WRITE_EA | FILE_APPEND_DATA | FILE_WRITE_DATA |
		FILE_READ_DATA);
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}
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static inline fmode_t cifs_posix_convert_flags(unsigned int flags)
{
	fmode_t posix_flags = 0;
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	if ((flags & O_ACCMODE) == O_RDONLY)
		posix_flags = FMODE_READ;
	else if ((flags & O_ACCMODE) == O_WRONLY)
		posix_flags = FMODE_WRITE;
	else if ((flags & O_ACCMODE) == O_RDWR) {
		/* GENERIC_ALL is too much permission to request
		   can cause unnecessary access denied on create */
		/* return GENERIC_ALL; */
		posix_flags = FMODE_READ | FMODE_WRITE;
	}
	/* can not map O_CREAT or O_EXCL or O_TRUNC flags when
	   reopening a file.  They had their effect on the original open */
	if (flags & O_APPEND)
		posix_flags |= (fmode_t)O_APPEND;
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	if (flags & O_DSYNC)
		posix_flags |= (fmode_t)O_DSYNC;
	if (flags & __O_SYNC)
		posix_flags |= (fmode_t)__O_SYNC;
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	if (flags & O_DIRECTORY)
		posix_flags |= (fmode_t)O_DIRECTORY;
	if (flags & O_NOFOLLOW)
		posix_flags |= (fmode_t)O_NOFOLLOW;
	if (flags & O_DIRECT)
		posix_flags |= (fmode_t)O_DIRECT;

	return posix_flags;
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}

static inline int cifs_get_disposition(unsigned int flags)
{
	if ((flags & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL))
		return FILE_CREATE;
	else if ((flags & (O_CREAT | O_TRUNC)) == (O_CREAT | O_TRUNC))
		return FILE_OVERWRITE_IF;
	else if ((flags & O_CREAT) == O_CREAT)
		return FILE_OPEN_IF;
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	else if ((flags & O_TRUNC) == O_TRUNC)
		return FILE_OVERWRITE;
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	else
		return FILE_OPEN;
}

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/* all arguments to this function must be checked for validity in caller */
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static inline int
cifs_posix_open_inode_helper(struct inode *inode, struct file *file,
			     struct cifsInodeInfo *pCifsInode,
			     struct cifsFileInfo *pCifsFile, __u32 oplock,
			     u16 netfid)
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{

	write_lock(&GlobalSMBSeslock);

	pCifsInode = CIFS_I(file->f_path.dentry->d_inode);
	if (pCifsInode == NULL) {
		write_unlock(&GlobalSMBSeslock);
		return -EINVAL;
	}

	if (pCifsInode->clientCanCacheRead) {
		/* we have the inode open somewhere else
		   no need to discard cache data */
		goto psx_client_can_cache;
	}

	/* BB FIXME need to fix this check to move it earlier into posix_open
	   BB  fIX following section BB FIXME */

	/* if not oplocked, invalidate inode pages if mtime or file
	   size changed */
/*	temp = cifs_NTtimeToUnix(le64_to_cpu(buf->LastWriteTime));
	if (timespec_equal(&file->f_path.dentry->d_inode->i_mtime, &temp) &&
			   (file->f_path.dentry->d_inode->i_size ==
			    (loff_t)le64_to_cpu(buf->EndOfFile))) {
		cFYI(1, ("inode unchanged on server"));
	} else {
		if (file->f_path.dentry->d_inode->i_mapping) {
			rc = filemap_write_and_wait(file->f_path.dentry->d_inode->i_mapping);
			if (rc != 0)
				CIFS_I(file->f_path.dentry->d_inode)->write_behind_rc = rc;
		}
		cFYI(1, ("invalidating remote inode since open detected it "
			 "changed"));
		invalidate_remote_inode(file->f_path.dentry->d_inode);
	} */

psx_client_can_cache:
	if ((oplock & 0xF) == OPLOCK_EXCLUSIVE) {
		pCifsInode->clientCanCacheAll = true;
		pCifsInode->clientCanCacheRead = true;
		cFYI(1, ("Exclusive Oplock granted on inode %p",
			 file->f_path.dentry->d_inode));
	} else if ((oplock & 0xF) == OPLOCK_READ)
		pCifsInode->clientCanCacheRead = true;

	/* will have to change the unlock if we reenable the
	   filemap_fdatawrite (which does not seem necessary */
	write_unlock(&GlobalSMBSeslock);
	return 0;
}

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static struct cifsFileInfo *
cifs_fill_filedata(struct file *file)
{
	struct list_head *tmp;
	struct cifsFileInfo *pCifsFile = NULL;
	struct cifsInodeInfo *pCifsInode = NULL;

	/* search inode for this file and fill in file->private_data */
	pCifsInode = CIFS_I(file->f_path.dentry->d_inode);
	read_lock(&GlobalSMBSeslock);
	list_for_each(tmp, &pCifsInode->openFileList) {
		pCifsFile = list_entry(tmp, struct cifsFileInfo, flist);
		if ((pCifsFile->pfile == NULL) &&
		    (pCifsFile->pid == current->tgid)) {
			/* mode set in cifs_create */

			/* needed for writepage */
			pCifsFile->pfile = file;
			file->private_data = pCifsFile;
			break;
		}
	}
	read_unlock(&GlobalSMBSeslock);

	if (file->private_data != NULL) {
		return pCifsFile;
	} else if ((file->f_flags & O_CREAT) && (file->f_flags & O_EXCL))
			cERROR(1, ("could not find file instance for "
				   "new file %p", file));
	return NULL;
}

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/* all arguments to this function must be checked for validity in caller */
static inline int cifs_open_inode_helper(struct inode *inode, struct file *file,
	struct cifsInodeInfo *pCifsInode, struct cifsFileInfo *pCifsFile,
	struct cifsTconInfo *pTcon, int *oplock, FILE_ALL_INFO *buf,
	char *full_path, int xid)
{
	struct timespec temp;
	int rc;

	if (pCifsInode->clientCanCacheRead) {
		/* we have the inode open somewhere else
		   no need to discard cache data */
		goto client_can_cache;
	}

	/* BB need same check in cifs_create too? */
	/* if not oplocked, invalidate inode pages if mtime or file
	   size changed */
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	temp = cifs_NTtimeToUnix(buf->LastWriteTime);
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	if (timespec_equal(&file->f_path.dentry->d_inode->i_mtime, &temp) &&
			   (file->f_path.dentry->d_inode->i_size ==
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			    (loff_t)le64_to_cpu(buf->EndOfFile))) {
		cFYI(1, ("inode unchanged on server"));
	} else {
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		if (file->f_path.dentry->d_inode->i_mapping) {
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		/* BB no need to lock inode until after invalidate
		   since namei code should already have it locked? */
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			rc = filemap_write_and_wait(file->f_path.dentry->d_inode->i_mapping);
			if (rc != 0)
				CIFS_I(file->f_path.dentry->d_inode)->write_behind_rc = rc;
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		}
		cFYI(1, ("invalidating remote inode since open detected it "
			 "changed"));
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		invalidate_remote_inode(file->f_path.dentry->d_inode);
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	}

client_can_cache:
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	if (pTcon->unix_ext)
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		rc = cifs_get_inode_info_unix(&file->f_path.dentry->d_inode,
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			full_path, inode->i_sb, xid);
	else
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		rc = cifs_get_inode_info(&file->f_path.dentry->d_inode,
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			full_path, buf, inode->i_sb, xid, NULL);
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	if ((*oplock & 0xF) == OPLOCK_EXCLUSIVE) {
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		pCifsInode->clientCanCacheAll = true;
		pCifsInode->clientCanCacheRead = true;
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		cFYI(1, ("Exclusive Oplock granted on inode %p",
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			 file->f_path.dentry->d_inode));
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	} else if ((*oplock & 0xF) == OPLOCK_READ)
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		pCifsInode->clientCanCacheRead = true;
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	return rc;
}

int cifs_open(struct inode *inode, struct file *file)
{
	int rc = -EACCES;
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	int xid;
	__u32 oplock;
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	struct cifs_sb_info *cifs_sb;
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	struct cifsTconInfo *tcon;
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	struct cifsFileInfo *pCifsFile;
	struct cifsInodeInfo *pCifsInode;
	char *full_path = NULL;
	int desiredAccess;
	int disposition;
	__u16 netfid;
	FILE_ALL_INFO *buf = NULL;

	xid = GetXid();

	cifs_sb = CIFS_SB(inode->i_sb);
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	tcon = cifs_sb->tcon;
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	pCifsInode = CIFS_I(file->f_path.dentry->d_inode);
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	pCifsFile = cifs_fill_filedata(file);
	if (pCifsFile) {
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		rc = 0;
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		FreeXid(xid);
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		return rc;
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	}
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	full_path = build_path_from_dentry(file->f_path.dentry);
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	if (full_path == NULL) {
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		rc = -ENOMEM;
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		FreeXid(xid);
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		return rc;
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	}

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	cFYI(1, ("inode = 0x%p file flags are 0x%x for %s",
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		 inode, file->f_flags, full_path));
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	if (oplockEnabled)
		oplock = REQ_OPLOCK;
	else
		oplock = 0;

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	if (!tcon->broken_posix_open && tcon->unix_ext &&
	    (tcon->ses->capabilities & CAP_UNIX) &&
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	    (CIFS_UNIX_POSIX_PATH_OPS_CAP &
			le64_to_cpu(tcon->fsUnixInfo.Capability))) {
		int oflags = (int) cifs_posix_convert_flags(file->f_flags);
		/* can not refresh inode info since size could be stale */
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		rc = cifs_posix_open(full_path, &inode, file->f_path.mnt,
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				     cifs_sb->mnt_file_mode /* ignored */,
				     oflags, &oplock, &netfid, xid);
		if (rc == 0) {
			cFYI(1, ("posix open succeeded"));
			/* no need for special case handling of setting mode
			   on read only files needed here */

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			pCifsFile = cifs_fill_filedata(file);
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			cifs_posix_open_inode_helper(inode, file, pCifsInode,
						     pCifsFile, oplock, netfid);
			goto out;
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		} else if ((rc == -EINVAL) || (rc == -EOPNOTSUPP)) {
			if (tcon->ses->serverNOS)
				cERROR(1, ("server %s of type %s returned"
					   " unexpected error on SMB posix open"
					   ", disabling posix open support."
					   " Check if server update available.",
					   tcon->ses->serverName,
					   tcon->ses->serverNOS));
			tcon->broken_posix_open = true;
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		} else if ((rc != -EIO) && (rc != -EREMOTE) &&
			 (rc != -EOPNOTSUPP)) /* path not found or net err */
			goto out;
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		/* else fallthrough to retry open the old way on network i/o
		   or DFS errors */
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	}

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	desiredAccess = cifs_convert_flags(file->f_flags);

/*********************************************************************
 *  open flag mapping table:
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 *
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 *	POSIX Flag            CIFS Disposition
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 *	----------            ----------------
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 *	O_CREAT               FILE_OPEN_IF
 *	O_CREAT | O_EXCL      FILE_CREATE
 *	O_CREAT | O_TRUNC     FILE_OVERWRITE_IF
 *	O_TRUNC               FILE_OVERWRITE
 *	none of the above     FILE_OPEN
 *
 *	Note that there is not a direct match between disposition
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 *	FILE_SUPERSEDE (ie create whether or not file exists although
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 *	O_CREAT | O_TRUNC is similar but truncates the existing
 *	file rather than creating a new file as FILE_SUPERSEDE does
 *	(which uses the attributes / metadata passed in on open call)
 *?
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 *?  O_SYNC is a reasonable match to CIFS writethrough flag
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 *?  and the read write flags match reasonably.  O_LARGEFILE
 *?  is irrelevant because largefile support is always used
 *?  by this client. Flags O_APPEND, O_DIRECT, O_DIRECTORY,
 *	 O_FASYNC, O_NOFOLLOW, O_NONBLOCK need further investigation
 *********************************************************************/

	disposition = cifs_get_disposition(file->f_flags);

	/* BB pass O_SYNC flag through on file attributes .. BB */

	/* Also refresh inode by passing in file_info buf returned by SMBOpen
	   and calling get_inode_info with returned buf (at least helps
	   non-Unix server case) */

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	/* BB we can not do this if this is the second open of a file
	   and the first handle has writebehind data, we might be
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	   able to simply do a filemap_fdatawrite/filemap_fdatawait first */
	buf = kmalloc(sizeof(FILE_ALL_INFO), GFP_KERNEL);
	if (!buf) {
		rc = -ENOMEM;
		goto out;
	}
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	if (cifs_sb->tcon->ses->capabilities & CAP_NT_SMBS)
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		rc = CIFSSMBOpen(xid, tcon, full_path, disposition,
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			 desiredAccess, CREATE_NOT_DIR, &netfid, &oplock, buf,
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			 cifs_sb->local_nls, cifs_sb->mnt_cifs_flags
				 & CIFS_MOUNT_MAP_SPECIAL_CHR);
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	else
		rc = -EIO; /* no NT SMB support fall into legacy open below */

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	if (rc == -EIO) {
		/* Old server, try legacy style OpenX */
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		rc = SMBLegacyOpen(xid, tcon, full_path, disposition,
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			desiredAccess, CREATE_NOT_DIR, &netfid, &oplock, buf,
			cifs_sb->local_nls, cifs_sb->mnt_cifs_flags
				& CIFS_MOUNT_MAP_SPECIAL_CHR);
	}
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	if (rc) {
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		cFYI(1, ("cifs_open returned 0x%x", rc));
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		goto out;
	}
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	pCifsFile = cifs_new_fileinfo(inode, netfid, file, file->f_path.mnt,
					file->f_flags);
	file->private_data = pCifsFile;
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	if (file->private_data == NULL) {
		rc = -ENOMEM;
		goto out;
	}

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	rc = cifs_open_inode_helper(inode, file, pCifsInode, pCifsFile, tcon,
				    &oplock, buf, full_path, xid);
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	if (oplock & CIFS_CREATE_ACTION) {
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		/* time to set mode which we can not set earlier due to
		   problems creating new read-only files */
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		if (tcon->unix_ext) {
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			struct cifs_unix_set_info_args args = {
				.mode	= inode->i_mode,
				.uid	= NO_CHANGE_64,
				.gid	= NO_CHANGE_64,
				.ctime	= NO_CHANGE_64,
				.atime	= NO_CHANGE_64,
				.mtime	= NO_CHANGE_64,
				.device	= 0,
			};
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			CIFSSMBUnixSetPathInfo(xid, tcon, full_path, &args,
					       cifs_sb->local_nls,
					       cifs_sb->mnt_cifs_flags &
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						CIFS_MOUNT_MAP_SPECIAL_CHR);
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		}
	}

out:
	kfree(buf);
	kfree(full_path);
	FreeXid(xid);
	return rc;
}

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/* Try to reacquire byte range locks that were released when session */
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/* to server was lost */
static int cifs_relock_file(struct cifsFileInfo *cifsFile)
{
	int rc = 0;

/* BB list all locks open on this file and relock */

	return rc;
}

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static int cifs_reopen_file(struct file *file, bool can_flush)
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{
	int rc = -EACCES;
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	int xid;
	__u32 oplock;
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	struct cifs_sb_info *cifs_sb;
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	struct cifsTconInfo *tcon;
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	struct cifsFileInfo *pCifsFile;
	struct cifsInodeInfo *pCifsInode;
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	struct inode *inode;
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	char *full_path = NULL;
	int desiredAccess;
	int disposition = FILE_OPEN;
	__u16 netfid;

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	if (file->private_data)
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		pCifsFile = (struct cifsFileInfo *)file->private_data;
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	else
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		return -EBADF;

	xid = GetXid();
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	mutex_lock(&pCifsFile->fh_mutex);
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	if (!pCifsFile->invalidHandle) {
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		mutex_unlock(&pCifsFile->fh_mutex);
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		rc = 0;
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		FreeXid(xid);
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		return rc;
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	}

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	if (file->f_path.dentry == NULL) {
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		cERROR(1, ("no valid name if dentry freed"));
		dump_stack();
		rc = -EBADF;
		goto reopen_error_exit;
	}

	inode = file->f_path.dentry->d_inode;
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	if (inode == NULL) {
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		cERROR(1, ("inode not valid"));
		dump_stack();
		rc = -EBADF;
		goto reopen_error_exit;
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	}
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	cifs_sb = CIFS_SB(inode->i_sb);
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	tcon = cifs_sb->tcon;
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/* can not grab rename sem here because various ops, including
   those that already have the rename sem can end up causing writepage
   to get called and if the server was down that means we end up here,
   and we can never tell if the caller already has the rename_sem */
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	full_path = build_path_from_dentry(file->f_path.dentry);
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	if (full_path == NULL) {
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		rc = -ENOMEM;
reopen_error_exit:
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		mutex_unlock(&pCifsFile->fh_mutex);
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		FreeXid(xid);
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		return rc;
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	}

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	cFYI(1, ("inode = 0x%p file flags 0x%x for %s",
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		 inode, file->f_flags, full_path));
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	if (oplockEnabled)
		oplock = REQ_OPLOCK;
	else
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		oplock = 0;
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509 510 511 512 513
	if (tcon->unix_ext && (tcon->ses->capabilities & CAP_UNIX) &&
	    (CIFS_UNIX_POSIX_PATH_OPS_CAP &
			le64_to_cpu(tcon->fsUnixInfo.Capability))) {
		int oflags = (int) cifs_posix_convert_flags(file->f_flags);
		/* can not refresh inode info since size could be stale */
514
		rc = cifs_posix_open(full_path, NULL, file->f_path.mnt,
515 516 517 518 519 520 521 522 523 524 525 526
				     cifs_sb->mnt_file_mode /* ignored */,
				     oflags, &oplock, &netfid, xid);
		if (rc == 0) {
			cFYI(1, ("posix reopen succeeded"));
			goto reopen_success;
		}
		/* fallthrough to retry open the old way on errors, especially
		   in the reconnect path it is important to retry hard */
	}

	desiredAccess = cifs_convert_flags(file->f_flags);

L
Linus Torvalds 已提交
527
	/* Can not refresh inode by passing in file_info buf to be returned
S
Steve French 已提交
528 529
	   by SMBOpen and then calling get_inode_info with returned buf
	   since file might have write behind data that needs to be flushed
L
Linus Torvalds 已提交
530 531 532
	   and server version of file size can be stale. If we knew for sure
	   that inode was not dirty locally we could do this */

533
	rc = CIFSSMBOpen(xid, tcon, full_path, disposition, desiredAccess,
L
Linus Torvalds 已提交
534
			 CREATE_NOT_DIR, &netfid, &oplock, NULL,
S
Steve French 已提交
535
			 cifs_sb->local_nls, cifs_sb->mnt_cifs_flags &
536
				CIFS_MOUNT_MAP_SPECIAL_CHR);
L
Linus Torvalds 已提交
537
	if (rc) {
538
		mutex_unlock(&pCifsFile->fh_mutex);
539 540
		cFYI(1, ("cifs_open returned 0x%x", rc));
		cFYI(1, ("oplock: %d", oplock));
L
Linus Torvalds 已提交
541
	} else {
542
reopen_success:
L
Linus Torvalds 已提交
543
		pCifsFile->netfid = netfid;
544
		pCifsFile->invalidHandle = false;
545
		mutex_unlock(&pCifsFile->fh_mutex);
L
Linus Torvalds 已提交
546 547 548
		pCifsInode = CIFS_I(inode);
		if (pCifsInode) {
			if (can_flush) {
549 550 551
				rc = filemap_write_and_wait(inode->i_mapping);
				if (rc != 0)
					CIFS_I(inode)->write_behind_rc = rc;
L
Linus Torvalds 已提交
552 553
			/* temporarily disable caching while we
			   go to server to get inode info */
554 555
				pCifsInode->clientCanCacheAll = false;
				pCifsInode->clientCanCacheRead = false;
556
				if (tcon->unix_ext)
L
Linus Torvalds 已提交
557 558 559 560 561
					rc = cifs_get_inode_info_unix(&inode,
						full_path, inode->i_sb, xid);
				else
					rc = cifs_get_inode_info(&inode,
						full_path, NULL, inode->i_sb,
562
						xid, NULL);
L
Linus Torvalds 已提交
563 564 565 566 567 568 569
			} /* else we are writing out data to server already
			     and could deadlock if we tried to flush data, and
			     since we do not know if we have data that would
			     invalidate the current end of file on the server
			     we can not go to the server to get the new inod
			     info */
			if ((oplock & 0xF) == OPLOCK_EXCLUSIVE) {
570 571
				pCifsInode->clientCanCacheAll = true;
				pCifsInode->clientCanCacheRead = true;
L
Linus Torvalds 已提交
572
				cFYI(1, ("Exclusive Oplock granted on inode %p",
573
					 file->f_path.dentry->d_inode));
L
Linus Torvalds 已提交
574
			} else if ((oplock & 0xF) == OPLOCK_READ) {
575 576
				pCifsInode->clientCanCacheRead = true;
				pCifsInode->clientCanCacheAll = false;
L
Linus Torvalds 已提交
577
			} else {
578 579
				pCifsInode->clientCanCacheRead = false;
				pCifsInode->clientCanCacheAll = false;
L
Linus Torvalds 已提交
580 581 582 583 584 585 586 587 588 589 590 591
			}
			cifs_relock_file(pCifsFile);
		}
	}
	kfree(full_path);
	FreeXid(xid);
	return rc;
}

int cifs_close(struct inode *inode, struct file *file)
{
	int rc = 0;
592
	int xid, timeout;
L
Linus Torvalds 已提交
593 594 595 596 597 598 599 600 601 602
	struct cifs_sb_info *cifs_sb;
	struct cifsTconInfo *pTcon;
	struct cifsFileInfo *pSMBFile =
		(struct cifsFileInfo *)file->private_data;

	xid = GetXid();

	cifs_sb = CIFS_SB(inode->i_sb);
	pTcon = cifs_sb->tcon;
	if (pSMBFile) {
J
[CIFS]  
Jeremy Allison 已提交
603
		struct cifsLockInfo *li, *tmp;
604
		write_lock(&GlobalSMBSeslock);
605
		pSMBFile->closePend = true;
L
Linus Torvalds 已提交
606 607 608
		if (pTcon) {
			/* no sense reconnecting to close a file that is
			   already closed */
S
Steve French 已提交
609
			if (!pTcon->need_reconnect) {
610
				write_unlock(&GlobalSMBSeslock);
611
				timeout = 2;
612
				while ((atomic_read(&pSMBFile->count) != 1)
613
					&& (timeout <= 2048)) {
614 615 616 617 618
					/* Give write a better chance to get to
					server ahead of the close.  We do not
					want to add a wait_q here as it would
					increase the memory utilization as
					the struct would be in each open file,
S
Steve French 已提交
619
					but this should give enough time to
620
					clear the socket */
621 622
					cFYI(DBG2,
						("close delay, write pending"));
623 624
					msleep(timeout);
					timeout *= 4;
625
				}
626 627 628
				if (!pTcon->need_reconnect &&
				    !pSMBFile->invalidHandle)
					rc = CIFSSMBClose(xid, pTcon,
L
Linus Torvalds 已提交
629
						  pSMBFile->netfid);
630 631 632 633
			} else
				write_unlock(&GlobalSMBSeslock);
		} else
			write_unlock(&GlobalSMBSeslock);
J
[CIFS]  
Jeremy Allison 已提交
634 635 636

		/* Delete any outstanding lock records.
		   We'll lose them when the file is closed anyway. */
637
		mutex_lock(&pSMBFile->lock_mutex);
J
[CIFS]  
Jeremy Allison 已提交
638 639 640 641
		list_for_each_entry_safe(li, tmp, &pSMBFile->llist, llist) {
			list_del(&li->llist);
			kfree(li);
		}
642
		mutex_unlock(&pSMBFile->lock_mutex);
J
[CIFS]  
Jeremy Allison 已提交
643

644
		write_lock(&GlobalSMBSeslock);
L
Linus Torvalds 已提交
645 646
		list_del(&pSMBFile->flist);
		list_del(&pSMBFile->tlist);
647
		write_unlock(&GlobalSMBSeslock);
648
		cifsFileInfo_put(file->private_data);
L
Linus Torvalds 已提交
649 650 651 652
		file->private_data = NULL;
	} else
		rc = -EBADF;

653
	read_lock(&GlobalSMBSeslock);
L
Linus Torvalds 已提交
654 655 656 657
	if (list_empty(&(CIFS_I(inode)->openFileList))) {
		cFYI(1, ("closing last open instance for inode %p", inode));
		/* if the file is not open we do not know if we can cache info
		   on this inode, much less write behind and read ahead */
658 659
		CIFS_I(inode)->clientCanCacheRead = false;
		CIFS_I(inode)->clientCanCacheAll  = false;
L
Linus Torvalds 已提交
660
	}
661
	read_unlock(&GlobalSMBSeslock);
S
Steve French 已提交
662
	if ((rc == 0) && CIFS_I(inode)->write_behind_rc)
L
Linus Torvalds 已提交
663 664 665 666 667 668 669 670 671 672 673 674 675
		rc = CIFS_I(inode)->write_behind_rc;
	FreeXid(xid);
	return rc;
}

int cifs_closedir(struct inode *inode, struct file *file)
{
	int rc = 0;
	int xid;
	struct cifsFileInfo *pCFileStruct =
	    (struct cifsFileInfo *)file->private_data;
	char *ptmp;

676
	cFYI(1, ("Closedir inode = 0x%p", inode));
L
Linus Torvalds 已提交
677 678 679 680 681

	xid = GetXid();

	if (pCFileStruct) {
		struct cifsTconInfo *pTcon;
S
Steve French 已提交
682 683
		struct cifs_sb_info *cifs_sb =
			CIFS_SB(file->f_path.dentry->d_sb);
L
Linus Torvalds 已提交
684 685 686 687

		pTcon = cifs_sb->tcon;

		cFYI(1, ("Freeing private data in close dir"));
688
		write_lock(&GlobalSMBSeslock);
689 690 691
		if (!pCFileStruct->srch_inf.endOfSearch &&
		    !pCFileStruct->invalidHandle) {
			pCFileStruct->invalidHandle = true;
692
			write_unlock(&GlobalSMBSeslock);
L
Linus Torvalds 已提交
693 694 695 696 697
			rc = CIFSFindClose(xid, pTcon, pCFileStruct->netfid);
			cFYI(1, ("Closing uncompleted readdir with rc %d",
				 rc));
			/* not much we can do if it fails anyway, ignore rc */
			rc = 0;
698 699
		} else
			write_unlock(&GlobalSMBSeslock);
L
Linus Torvalds 已提交
700 701
		ptmp = pCFileStruct->srch_inf.ntwrk_buf_start;
		if (ptmp) {
702
			cFYI(1, ("closedir free smb buf in srch struct"));
L
Linus Torvalds 已提交
703
			pCFileStruct->srch_inf.ntwrk_buf_start = NULL;
S
Steve French 已提交
704
			if (pCFileStruct->srch_inf.smallBuf)
705 706 707
				cifs_small_buf_release(ptmp);
			else
				cifs_buf_release(ptmp);
L
Linus Torvalds 已提交
708 709 710 711 712 713 714 715 716
		}
		kfree(file->private_data);
		file->private_data = NULL;
	}
	/* BB can we lock the filestruct while this is going on? */
	FreeXid(xid);
	return rc;
}

J
[CIFS]  
Jeremy Allison 已提交
717 718 719
static int store_file_lock(struct cifsFileInfo *fid, __u64 len,
				__u64 offset, __u8 lockType)
{
S
Steve French 已提交
720 721
	struct cifsLockInfo *li =
		kmalloc(sizeof(struct cifsLockInfo), GFP_KERNEL);
J
[CIFS]  
Jeremy Allison 已提交
722 723 724 725 726
	if (li == NULL)
		return -ENOMEM;
	li->offset = offset;
	li->length = len;
	li->type = lockType;
727
	mutex_lock(&fid->lock_mutex);
J
[CIFS]  
Jeremy Allison 已提交
728
	list_add(&li->llist, &fid->llist);
729
	mutex_unlock(&fid->lock_mutex);
J
[CIFS]  
Jeremy Allison 已提交
730 731 732
	return 0;
}

L
Linus Torvalds 已提交
733 734 735 736 737 738
int cifs_lock(struct file *file, int cmd, struct file_lock *pfLock)
{
	int rc, xid;
	__u32 numLock = 0;
	__u32 numUnlock = 0;
	__u64 length;
739
	bool wait_flag = false;
L
Linus Torvalds 已提交
740
	struct cifs_sb_info *cifs_sb;
741
	struct cifsTconInfo *tcon;
742 743
	__u16 netfid;
	__u8 lockType = LOCKING_ANDX_LARGE_FILES;
744
	bool posix_locking = 0;
L
Linus Torvalds 已提交
745 746 747 748 749 750 751

	length = 1 + pfLock->fl_end - pfLock->fl_start;
	rc = -EACCES;
	xid = GetXid();

	cFYI(1, ("Lock parm: 0x%x flockflags: "
		 "0x%x flocktype: 0x%x start: %lld end: %lld",
S
Steve French 已提交
752 753
		cmd, pfLock->fl_flags, pfLock->fl_type, pfLock->fl_start,
		pfLock->fl_end));
L
Linus Torvalds 已提交
754 755

	if (pfLock->fl_flags & FL_POSIX)
756
		cFYI(1, ("Posix"));
L
Linus Torvalds 已提交
757
	if (pfLock->fl_flags & FL_FLOCK)
758
		cFYI(1, ("Flock"));
L
Linus Torvalds 已提交
759
	if (pfLock->fl_flags & FL_SLEEP) {
760
		cFYI(1, ("Blocking lock"));
761
		wait_flag = true;
L
Linus Torvalds 已提交
762 763 764
	}
	if (pfLock->fl_flags & FL_ACCESS)
		cFYI(1, ("Process suspended by mandatory locking - "
765
			 "not implemented yet"));
L
Linus Torvalds 已提交
766 767
	if (pfLock->fl_flags & FL_LEASE)
		cFYI(1, ("Lease on file - not implemented yet"));
S
Steve French 已提交
768
	if (pfLock->fl_flags &
L
Linus Torvalds 已提交
769 770 771 772 773 774 775
	    (~(FL_POSIX | FL_FLOCK | FL_SLEEP | FL_ACCESS | FL_LEASE)))
		cFYI(1, ("Unknown lock flags 0x%x", pfLock->fl_flags));

	if (pfLock->fl_type == F_WRLCK) {
		cFYI(1, ("F_WRLCK "));
		numLock = 1;
	} else if (pfLock->fl_type == F_UNLCK) {
776
		cFYI(1, ("F_UNLCK"));
L
Linus Torvalds 已提交
777
		numUnlock = 1;
778 779
		/* Check if unlock includes more than
		one lock range */
L
Linus Torvalds 已提交
780
	} else if (pfLock->fl_type == F_RDLCK) {
781
		cFYI(1, ("F_RDLCK"));
L
Linus Torvalds 已提交
782 783 784
		lockType |= LOCKING_ANDX_SHARED_LOCK;
		numLock = 1;
	} else if (pfLock->fl_type == F_EXLCK) {
785
		cFYI(1, ("F_EXLCK"));
L
Linus Torvalds 已提交
786 787
		numLock = 1;
	} else if (pfLock->fl_type == F_SHLCK) {
788
		cFYI(1, ("F_SHLCK"));
L
Linus Torvalds 已提交
789 790 791
		lockType |= LOCKING_ANDX_SHARED_LOCK;
		numLock = 1;
	} else
792
		cFYI(1, ("Unknown type of lock"));
L
Linus Torvalds 已提交
793

794
	cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
795
	tcon = cifs_sb->tcon;
L
Linus Torvalds 已提交
796 797

	if (file->private_data == NULL) {
798
		rc = -EBADF;
L
Linus Torvalds 已提交
799
		FreeXid(xid);
800
		return rc;
L
Linus Torvalds 已提交
801
	}
802 803
	netfid = ((struct cifsFileInfo *)file->private_data)->netfid;

804 805
	if ((tcon->ses->capabilities & CAP_UNIX) &&
	    (CIFS_UNIX_FCNTL_CAP & le64_to_cpu(tcon->fsUnixInfo.Capability)) &&
S
Steve French 已提交
806
	    ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOPOSIXBRL) == 0))
807
		posix_locking = 1;
808 809 810
	/* BB add code here to normalize offset and length to
	account for negative length which we can not accept over the
	wire */
L
Linus Torvalds 已提交
811
	if (IS_GETLK(cmd)) {
S
Steve French 已提交
812
		if (posix_locking) {
813
			int posix_lock_type;
S
Steve French 已提交
814
			if (lockType & LOCKING_ANDX_SHARED_LOCK)
815 816 817
				posix_lock_type = CIFS_RDLCK;
			else
				posix_lock_type = CIFS_WRLCK;
818
			rc = CIFSSMBPosixLock(xid, tcon, netfid, 1 /* get */,
819
					length,	pfLock,
820 821 822 823 824 825
					posix_lock_type, wait_flag);
			FreeXid(xid);
			return rc;
		}

		/* BB we could chain these into one lock request BB */
826
		rc = CIFSSMBLock(xid, tcon, netfid, length, pfLock->fl_start,
827
				 0, 1, lockType, 0 /* wait flag */ );
L
Linus Torvalds 已提交
828
		if (rc == 0) {
829
			rc = CIFSSMBLock(xid, tcon, netfid, length,
L
Linus Torvalds 已提交
830 831 832 833 834 835
					 pfLock->fl_start, 1 /* numUnlock */ ,
					 0 /* numLock */ , lockType,
					 0 /* wait flag */ );
			pfLock->fl_type = F_UNLCK;
			if (rc != 0)
				cERROR(1, ("Error unlocking previously locked "
836
					   "range %d during test of lock", rc));
L
Linus Torvalds 已提交
837 838 839 840 841 842 843 844 845 846 847
			rc = 0;

		} else {
			/* if rc == ERR_SHARING_VIOLATION ? */
			rc = 0;	/* do not change lock type to unlock
				   since range in use */
		}

		FreeXid(xid);
		return rc;
	}
J
[CIFS]  
Jeremy Allison 已提交
848 849 850 851 852 853 854 855 856

	if (!numLock && !numUnlock) {
		/* if no lock or unlock then nothing
		to do since we do not know what it is */
		FreeXid(xid);
		return -EOPNOTSUPP;
	}

	if (posix_locking) {
857
		int posix_lock_type;
S
Steve French 已提交
858
		if (lockType & LOCKING_ANDX_SHARED_LOCK)
859 860 861
			posix_lock_type = CIFS_RDLCK;
		else
			posix_lock_type = CIFS_WRLCK;
862

S
Steve French 已提交
863
		if (numUnlock == 1)
864
			posix_lock_type = CIFS_UNLCK;
J
[CIFS]  
Jeremy Allison 已提交
865

866
		rc = CIFSSMBPosixLock(xid, tcon, netfid, 0 /* set */,
867
				      length, pfLock,
868
				      posix_lock_type, wait_flag);
J
[CIFS]  
Jeremy Allison 已提交
869
	} else {
S
Steve French 已提交
870 871
		struct cifsFileInfo *fid =
			(struct cifsFileInfo *)file->private_data;
J
[CIFS]  
Jeremy Allison 已提交
872 873

		if (numLock) {
874
			rc = CIFSSMBLock(xid, tcon, netfid, length,
S
Steve French 已提交
875
					pfLock->fl_start,
J
[CIFS]  
Jeremy Allison 已提交
876 877 878 879 880 881 882 883 884 885 886 887 888
					0, numLock, lockType, wait_flag);

			if (rc == 0) {
				/* For Windows locks we must store them. */
				rc = store_file_lock(fid, length,
						pfLock->fl_start, lockType);
			}
		} else if (numUnlock) {
			/* For each stored lock that this unlock overlaps
			   completely, unlock it. */
			int stored_rc = 0;
			struct cifsLockInfo *li, *tmp;

889
			rc = 0;
890
			mutex_lock(&fid->lock_mutex);
J
[CIFS]  
Jeremy Allison 已提交
891 892
			list_for_each_entry_safe(li, tmp, &fid->llist, llist) {
				if (pfLock->fl_start <= li->offset &&
S
Steve French 已提交
893
						(pfLock->fl_start + length) >=
894
						(li->offset + li->length)) {
895
					stored_rc = CIFSSMBLock(xid, tcon,
S
Steve French 已提交
896
							netfid,
J
[CIFS]  
Jeremy Allison 已提交
897
							li->length, li->offset,
898
							1, 0, li->type, false);
J
[CIFS]  
Jeremy Allison 已提交
899 900 901 902 903 904 905
					if (stored_rc)
						rc = stored_rc;

					list_del(&li->llist);
					kfree(li);
				}
			}
906
			mutex_unlock(&fid->lock_mutex);
J
[CIFS]  
Jeremy Allison 已提交
907 908 909
		}
	}

910
	if (pfLock->fl_flags & FL_POSIX)
L
Linus Torvalds 已提交
911 912 913 914 915
		posix_lock_file_wait(file, pfLock);
	FreeXid(xid);
	return rc;
}

916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949
/*
 * Set the timeout on write requests past EOF. For some servers (Windows)
 * these calls can be very long.
 *
 * If we're writing >10M past the EOF we give a 180s timeout. Anything less
 * than that gets a 45s timeout. Writes not past EOF get 15s timeouts.
 * The 10M cutoff is totally arbitrary. A better scheme for this would be
 * welcome if someone wants to suggest one.
 *
 * We may be able to do a better job with this if there were some way to
 * declare that a file should be sparse.
 */
static int
cifs_write_timeout(struct cifsInodeInfo *cifsi, loff_t offset)
{
	if (offset <= cifsi->server_eof)
		return CIFS_STD_OP;
	else if (offset > (cifsi->server_eof + (10 * 1024 * 1024)))
		return CIFS_VLONG_OP;
	else
		return CIFS_LONG_OP;
}

/* update the file size (if needed) after a write */
static void
cifs_update_eof(struct cifsInodeInfo *cifsi, loff_t offset,
		      unsigned int bytes_written)
{
	loff_t end_of_write = offset + bytes_written;

	if (end_of_write > cifsi->server_eof)
		cifsi->server_eof = end_of_write;
}

L
Linus Torvalds 已提交
950 951 952 953 954 955 956 957 958 959
ssize_t cifs_user_write(struct file *file, const char __user *write_data,
	size_t write_size, loff_t *poffset)
{
	int rc = 0;
	unsigned int bytes_written = 0;
	unsigned int total_written;
	struct cifs_sb_info *cifs_sb;
	struct cifsTconInfo *pTcon;
	int xid, long_op;
	struct cifsFileInfo *open_file;
960
	struct cifsInodeInfo *cifsi = CIFS_I(file->f_path.dentry->d_inode);
L
Linus Torvalds 已提交
961

962
	cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
L
Linus Torvalds 已提交
963 964 965 966 967

	pTcon = cifs_sb->tcon;

	/* cFYI(1,
	   (" write %d bytes to offset %lld of %s", write_size,
968
	   *poffset, file->f_path.dentry->d_name.name)); */
L
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	if (file->private_data == NULL)
		return -EBADF;
972
	open_file = (struct cifsFileInfo *) file->private_data;
973

974 975 976 977
	rc = generic_write_checks(file, poffset, &write_size, 0);
	if (rc)
		return rc;

L
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	xid = GetXid();

980
	long_op = cifs_write_timeout(cifsi, *poffset);
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	for (total_written = 0; write_size > total_written;
	     total_written += bytes_written) {
		rc = -EAGAIN;
		while (rc == -EAGAIN) {
			if (file->private_data == NULL) {
				/* file has been closed on us */
				FreeXid(xid);
			/* if we have gotten here we have written some data
			   and blocked, and the file has been freed on us while
			   we blocked so return what we managed to write */
				return total_written;
S
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992
			}
L
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993 994 995 996 997 998 999 1000 1001 1002 1003 1004
			if (open_file->closePend) {
				FreeXid(xid);
				if (total_written)
					return total_written;
				else
					return -EBADF;
			}
			if (open_file->invalidHandle) {
				/* we could deadlock if we called
				   filemap_fdatawait from here so tell
				   reopen_file not to flush data to server
				   now */
1005
				rc = cifs_reopen_file(file, false);
L
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1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023
				if (rc != 0)
					break;
			}

			rc = CIFSSMBWrite(xid, pTcon,
				open_file->netfid,
				min_t(const int, cifs_sb->wsize,
				      write_size - total_written),
				*poffset, &bytes_written,
				NULL, write_data + total_written, long_op);
		}
		if (rc || (bytes_written == 0)) {
			if (total_written)
				break;
			else {
				FreeXid(xid);
				return rc;
			}
1024 1025
		} else {
			cifs_update_eof(cifsi, *poffset, bytes_written);
L
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1026
			*poffset += bytes_written;
1027
		}
1028
		long_op = CIFS_STD_OP; /* subsequent writes fast -
L
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1029 1030 1031
				    15 seconds is plenty */
	}

1032
	cifs_stats_bytes_written(pTcon, total_written);
L
Linus Torvalds 已提交
1033 1034

	/* since the write may have blocked check these pointers again */
1035 1036
	if ((file->f_path.dentry) && (file->f_path.dentry->d_inode)) {
		struct inode *inode = file->f_path.dentry->d_inode;
S
Steve French 已提交
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/* Do not update local mtime - server will set its actual value on write
 *		inode->i_ctime = inode->i_mtime =
1039 1040 1041 1042 1043
 * 			current_fs_time(inode->i_sb);*/
		if (total_written > 0) {
			spin_lock(&inode->i_lock);
			if (*poffset > file->f_path.dentry->d_inode->i_size)
				i_size_write(file->f_path.dentry->d_inode,
L
Linus Torvalds 已提交
1044
					*poffset);
1045
			spin_unlock(&inode->i_lock);
L
Linus Torvalds 已提交
1046
		}
S
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1047
		mark_inode_dirty_sync(file->f_path.dentry->d_inode);
L
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1048 1049 1050 1051 1052 1053
	}
	FreeXid(xid);
	return total_written;
}

static ssize_t cifs_write(struct file *file, const char *write_data,
N
Nick Piggin 已提交
1054
			  size_t write_size, loff_t *poffset)
L
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1055 1056 1057 1058 1059 1060 1061 1062
{
	int rc = 0;
	unsigned int bytes_written = 0;
	unsigned int total_written;
	struct cifs_sb_info *cifs_sb;
	struct cifsTconInfo *pTcon;
	int xid, long_op;
	struct cifsFileInfo *open_file;
1063
	struct cifsInodeInfo *cifsi = CIFS_I(file->f_path.dentry->d_inode);
L
Linus Torvalds 已提交
1064

1065
	cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
L
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1066 1067 1068

	pTcon = cifs_sb->tcon;

S
Steve French 已提交
1069
	cFYI(1, ("write %zd bytes to offset %lld of %s", write_size,
1070
	   *poffset, file->f_path.dentry->d_name.name));
L
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1071 1072 1073

	if (file->private_data == NULL)
		return -EBADF;
1074
	open_file = (struct cifsFileInfo *)file->private_data;
1075

L
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1076 1077
	xid = GetXid();

1078
	long_op = cifs_write_timeout(cifsi, *poffset);
L
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1079 1080 1081 1082 1083 1084 1085 1086 1087
	for (total_written = 0; write_size > total_written;
	     total_written += bytes_written) {
		rc = -EAGAIN;
		while (rc == -EAGAIN) {
			if (file->private_data == NULL) {
				/* file has been closed on us */
				FreeXid(xid);
			/* if we have gotten here we have written some data
			   and blocked, and the file has been freed on us
S
Steve French 已提交
1088
			   while we blocked so return what we managed to
L
Linus Torvalds 已提交
1089 1090
			   write */
				return total_written;
S
Steve French 已提交
1091
			}
L
Linus Torvalds 已提交
1092 1093 1094 1095 1096 1097 1098 1099 1100 1101
			if (open_file->closePend) {
				FreeXid(xid);
				if (total_written)
					return total_written;
				else
					return -EBADF;
			}
			if (open_file->invalidHandle) {
				/* we could deadlock if we called
				   filemap_fdatawait from here so tell
S
Steve French 已提交
1102
				   reopen_file not to flush data to
L
Linus Torvalds 已提交
1103
				   server now */
1104
				rc = cifs_reopen_file(file, false);
L
Linus Torvalds 已提交
1105 1106 1107
				if (rc != 0)
					break;
			}
S
Steve French 已提交
1108 1109
			if (experimEnabled || (pTcon->ses->server &&
				((pTcon->ses->server->secMode &
S
Steve French 已提交
1110
				(SECMODE_SIGN_REQUIRED | SECMODE_SIGN_ENABLED))
S
Steve French 已提交
1111
				== 0))) {
1112 1113 1114
				struct kvec iov[2];
				unsigned int len;

1115
				len = min((size_t)cifs_sb->wsize,
1116 1117 1118 1119 1120
					  write_size - total_written);
				/* iov[0] is reserved for smb header */
				iov[1].iov_base = (char *)write_data +
						  total_written;
				iov[1].iov_len = len;
1121
				rc = CIFSSMBWrite2(xid, pTcon,
1122
						open_file->netfid, len,
1123
						*poffset, &bytes_written,
1124
						iov, 1, long_op);
1125
			} else
1126 1127 1128 1129 1130 1131 1132
				rc = CIFSSMBWrite(xid, pTcon,
					 open_file->netfid,
					 min_t(const int, cifs_sb->wsize,
					       write_size - total_written),
					 *poffset, &bytes_written,
					 write_data + total_written,
					 NULL, long_op);
L
Linus Torvalds 已提交
1133 1134 1135 1136 1137 1138 1139 1140
		}
		if (rc || (bytes_written == 0)) {
			if (total_written)
				break;
			else {
				FreeXid(xid);
				return rc;
			}
1141 1142
		} else {
			cifs_update_eof(cifsi, *poffset, bytes_written);
L
Linus Torvalds 已提交
1143
			*poffset += bytes_written;
1144
		}
1145
		long_op = CIFS_STD_OP; /* subsequent writes fast -
L
Linus Torvalds 已提交
1146 1147 1148
				    15 seconds is plenty */
	}

1149
	cifs_stats_bytes_written(pTcon, total_written);
L
Linus Torvalds 已提交
1150 1151

	/* since the write may have blocked check these pointers again */
1152
	if ((file->f_path.dentry) && (file->f_path.dentry->d_inode)) {
1153
/*BB We could make this contingent on superblock ATIME flag too */
1154 1155 1156 1157 1158 1159 1160 1161
/*		file->f_path.dentry->d_inode->i_ctime =
		file->f_path.dentry->d_inode->i_mtime = CURRENT_TIME;*/
		if (total_written > 0) {
			spin_lock(&file->f_path.dentry->d_inode->i_lock);
			if (*poffset > file->f_path.dentry->d_inode->i_size)
				i_size_write(file->f_path.dentry->d_inode,
					     *poffset);
			spin_unlock(&file->f_path.dentry->d_inode->i_lock);
L
Linus Torvalds 已提交
1162
		}
1163
		mark_inode_dirty_sync(file->f_path.dentry->d_inode);
L
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1164 1165 1166 1167 1168
	}
	FreeXid(xid);
	return total_written;
}

S
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1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185
#ifdef CONFIG_CIFS_EXPERIMENTAL
struct cifsFileInfo *find_readable_file(struct cifsInodeInfo *cifs_inode)
{
	struct cifsFileInfo *open_file = NULL;

	read_lock(&GlobalSMBSeslock);
	/* we could simply get the first_list_entry since write-only entries
	   are always at the end of the list but since the first entry might
	   have a close pending, we go through the whole list */
	list_for_each_entry(open_file, &cifs_inode->openFileList, flist) {
		if (open_file->closePend)
			continue;
		if (open_file->pfile && ((open_file->pfile->f_flags & O_RDWR) ||
		    (open_file->pfile->f_flags & O_RDONLY))) {
			if (!open_file->invalidHandle) {
				/* found a good file */
				/* lock it so it will not be closed on us */
1186
				cifsFileInfo_get(open_file);
S
Steve French 已提交
1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199
				read_unlock(&GlobalSMBSeslock);
				return open_file;
			} /* else might as well continue, and look for
			     another, or simply have the caller reopen it
			     again rather than trying to fix this handle */
		} else /* write only file */
			break; /* write only files are last so must be done */
	}
	read_unlock(&GlobalSMBSeslock);
	return NULL;
}
#endif

1200
struct cifsFileInfo *find_writable_file(struct cifsInodeInfo *cifs_inode)
1201 1202
{
	struct cifsFileInfo *open_file;
1203
	bool any_available = false;
1204
	int rc;
1205

1206 1207 1208 1209
	/* Having a null inode here (because mapping->host was set to zero by
	the VFS or MM) should not happen but we had reports of on oops (due to
	it being zero) during stress testcases so we need to check for it */

S
Steve French 已提交
1210 1211
	if (cifs_inode == NULL) {
		cERROR(1, ("Null inode passed to cifs_writeable_file"));
1212 1213 1214 1215
		dump_stack();
		return NULL;
	}

1216
	read_lock(&GlobalSMBSeslock);
1217
refind_writable:
1218
	list_for_each_entry(open_file, &cifs_inode->openFileList, flist) {
1219 1220
		if (open_file->closePend ||
		    (!any_available && open_file->pid != current->tgid))
1221
			continue;
1222

1223 1224 1225
		if (open_file->pfile &&
		    ((open_file->pfile->f_flags & O_RDWR) ||
		     (open_file->pfile->f_flags & O_WRONLY))) {
1226
			cifsFileInfo_get(open_file);
1227 1228 1229 1230 1231 1232

			if (!open_file->invalidHandle) {
				/* found a good writable file */
				read_unlock(&GlobalSMBSeslock);
				return open_file;
			}
S
Steve French 已提交
1233

1234
			read_unlock(&GlobalSMBSeslock);
1235
			/* Had to unlock since following call can block */
1236
			rc = cifs_reopen_file(open_file->pfile, false);
S
Steve French 已提交
1237
			if (!rc) {
1238 1239 1240 1241
				if (!open_file->closePend)
					return open_file;
				else { /* start over in case this was deleted */
				       /* since the list could be modified */
1242
					read_lock(&GlobalSMBSeslock);
1243
					cifsFileInfo_put(open_file);
1244
					goto refind_writable;
1245 1246
				}
			}
1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258

			/* if it fails, try another handle if possible -
			(we can not do this if closePending since
			loop could be modified - in which case we
			have to start at the beginning of the list
			again. Note that it would be bad
			to hold up writepages here (rather than
			in caller) with continuous retries */
			cFYI(1, ("wp failed on reopen file"));
			read_lock(&GlobalSMBSeslock);
			/* can not use this handle, no write
			   pending on this one after all */
1259
			cifsFileInfo_put(open_file);
S
Steve French 已提交
1260

1261 1262 1263 1264 1265 1266 1267 1268 1269
			if (open_file->closePend) /* list could have changed */
				goto refind_writable;
			/* else we simply continue to the next entry. Thus
			   we do not loop on reopen errors.  If we
			   can not reopen the file, for example if we
			   reconnected to a server with another client
			   racing to delete or lock the file we would not
			   make progress if we restarted before the beginning
			   of the loop here. */
1270 1271
		}
	}
1272 1273 1274 1275 1276
	/* couldn't find useable FH with same pid, try any available */
	if (!any_available) {
		any_available = true;
		goto refind_writable;
	}
1277 1278 1279 1280
	read_unlock(&GlobalSMBSeslock);
	return NULL;
}

L
Linus Torvalds 已提交
1281 1282 1283 1284 1285 1286 1287 1288 1289 1290
static int cifs_partialpagewrite(struct page *page, unsigned from, unsigned to)
{
	struct address_space *mapping = page->mapping;
	loff_t offset = (loff_t)page->index << PAGE_CACHE_SHIFT;
	char *write_data;
	int rc = -EFAULT;
	int bytes_written = 0;
	struct cifs_sb_info *cifs_sb;
	struct cifsTconInfo *pTcon;
	struct inode *inode;
1291
	struct cifsFileInfo *open_file;
L
Linus Torvalds 已提交
1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 1314 1315 1316

	if (!mapping || !mapping->host)
		return -EFAULT;

	inode = page->mapping->host;
	cifs_sb = CIFS_SB(inode->i_sb);
	pTcon = cifs_sb->tcon;

	offset += (loff_t)from;
	write_data = kmap(page);
	write_data += from;

	if ((to > PAGE_CACHE_SIZE) || (from > to)) {
		kunmap(page);
		return -EIO;
	}

	/* racing with truncate? */
	if (offset > mapping->host->i_size) {
		kunmap(page);
		return 0; /* don't care */
	}

	/* check to make sure that we are not extending the file */
	if (mapping->host->i_size - offset < (loff_t)to)
S
Steve French 已提交
1317
		to = (unsigned)(mapping->host->i_size - offset);
L
Linus Torvalds 已提交
1318

1319 1320 1321 1322
	open_file = find_writable_file(CIFS_I(mapping->host));
	if (open_file) {
		bytes_written = cifs_write(open_file->pfile, write_data,
					   to-from, &offset);
1323
		cifsFileInfo_put(open_file);
L
Linus Torvalds 已提交
1324
		/* Does mm or vfs already set times? */
1325
		inode->i_atime = inode->i_mtime = current_fs_time(inode->i_sb);
1326
		if ((bytes_written > 0) && (offset))
1327
			rc = 0;
1328 1329
		else if (bytes_written < 0)
			rc = bytes_written;
1330
	} else {
L
Linus Torvalds 已提交
1331 1332 1333 1334 1335 1336 1337 1338 1339
		cFYI(1, ("No writeable filehandles for inode"));
		rc = -EIO;
	}

	kunmap(page);
	return rc;
}

static int cifs_writepages(struct address_space *mapping,
1340
			   struct writeback_control *wbc)
L
Linus Torvalds 已提交
1341
{
1342 1343 1344 1345 1346
	struct backing_dev_info *bdi = mapping->backing_dev_info;
	unsigned int bytes_to_write;
	unsigned int bytes_written;
	struct cifs_sb_info *cifs_sb;
	int done = 0;
1347
	pgoff_t end;
1348
	pgoff_t index;
S
Steve French 已提交
1349 1350
	int range_whole = 0;
	struct kvec *iov;
1351
	int len;
1352 1353 1354 1355
	int n_iov = 0;
	pgoff_t next;
	int nr_pages;
	__u64 offset = 0;
1356
	struct cifsFileInfo *open_file;
1357
	struct cifsInodeInfo *cifsi = CIFS_I(mapping->host);
1358 1359 1360 1361
	struct page *page;
	struct pagevec pvec;
	int rc = 0;
	int scanned = 0;
1362
	int xid, long_op;
L
Linus Torvalds 已提交
1363

1364
	cifs_sb = CIFS_SB(mapping->host->i_sb);
1365

1366 1367 1368 1369 1370 1371 1372
	/*
	 * If wsize is smaller that the page cache size, default to writing
	 * one page at a time via cifs_writepage
	 */
	if (cifs_sb->wsize < PAGE_CACHE_SIZE)
		return generic_writepages(mapping, wbc);

S
Steve French 已提交
1373 1374 1375 1376
	if ((cifs_sb->tcon->ses) && (cifs_sb->tcon->ses->server))
		if (cifs_sb->tcon->ses->server->secMode &
				(SECMODE_SIGN_REQUIRED | SECMODE_SIGN_ENABLED))
			if (!experimEnabled)
1377
				return generic_writepages(mapping, wbc);
1378

1379
	iov = kmalloc(32 * sizeof(struct kvec), GFP_KERNEL);
S
Steve French 已提交
1380
	if (iov == NULL)
1381 1382 1383
		return generic_writepages(mapping, wbc);


1384 1385 1386 1387 1388 1389
	/*
	 * BB: Is this meaningful for a non-block-device file system?
	 * If it is, we should test it again after we do I/O
	 */
	if (wbc->nonblocking && bdi_write_congested(bdi)) {
		wbc->encountered_congestion = 1;
1390
		kfree(iov);
1391 1392 1393
		return 0;
	}

L
Linus Torvalds 已提交
1394 1395
	xid = GetXid();

1396
	pagevec_init(&pvec, 0);
1397
	if (wbc->range_cyclic) {
1398
		index = mapping->writeback_index; /* Start from prev offset */
1399 1400 1401 1402 1403 1404
		end = -1;
	} else {
		index = wbc->range_start >> PAGE_CACHE_SHIFT;
		end = wbc->range_end >> PAGE_CACHE_SHIFT;
		if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX)
			range_whole = 1;
1405 1406 1407 1408 1409 1410 1411 1412 1413 1414 1415 1416 1417 1418 1419 1420 1421 1422 1423 1424 1425 1426 1427 1428 1429 1430 1431
		scanned = 1;
	}
retry:
	while (!done && (index <= end) &&
	       (nr_pages = pagevec_lookup_tag(&pvec, mapping, &index,
			PAGECACHE_TAG_DIRTY,
			min(end - index, (pgoff_t)PAGEVEC_SIZE - 1) + 1))) {
		int first;
		unsigned int i;

		first = -1;
		next = 0;
		n_iov = 0;
		bytes_to_write = 0;

		for (i = 0; i < nr_pages; i++) {
			page = pvec.pages[i];
			/*
			 * At this point we hold neither mapping->tree_lock nor
			 * lock on the page itself: the page may be truncated or
			 * invalidated (changing page->mapping to NULL), or even
			 * swizzled back from swapper_space to tmpfs file
			 * mapping
			 */

			if (first < 0)
				lock_page(page);
N
Nick Piggin 已提交
1432
			else if (!trylock_page(page))
1433 1434 1435 1436 1437 1438 1439
				break;

			if (unlikely(page->mapping != mapping)) {
				unlock_page(page);
				break;
			}

1440
			if (!wbc->range_cyclic && page->index > end) {
1441 1442 1443 1444 1445 1446 1447 1448 1449 1450 1451 1452 1453 1454 1455
				done = 1;
				unlock_page(page);
				break;
			}

			if (next && (page->index != next)) {
				/* Not next consecutive page */
				unlock_page(page);
				break;
			}

			if (wbc->sync_mode != WB_SYNC_NONE)
				wait_on_page_writeback(page);

			if (PageWriteback(page) ||
1456
					!clear_page_dirty_for_io(page)) {
1457 1458 1459
				unlock_page(page);
				break;
			}
1460

1461 1462 1463 1464 1465 1466
			/*
			 * This actually clears the dirty bit in the radix tree.
			 * See cifs_writepage() for more commentary.
			 */
			set_page_writeback(page);

1467 1468 1469
			if (page_offset(page) >= mapping->host->i_size) {
				done = 1;
				unlock_page(page);
1470
				end_page_writeback(page);
1471 1472 1473
				break;
			}

1474 1475 1476 1477 1478
			/*
			 * BB can we get rid of this?  pages are held by pvec
			 */
			page_cache_get(page);

1479 1480 1481
			len = min(mapping->host->i_size - page_offset(page),
				  (loff_t)PAGE_CACHE_SIZE);

1482 1483 1484
			/* reserve iov[0] for the smb header */
			n_iov++;
			iov[n_iov].iov_base = kmap(page);
1485 1486
			iov[n_iov].iov_len = len;
			bytes_to_write += len;
1487 1488 1489 1490 1491 1492 1493 1494 1495 1496

			if (first < 0) {
				first = i;
				offset = page_offset(page);
			}
			next = page->index + 1;
			if (bytes_to_write + PAGE_CACHE_SIZE > cifs_sb->wsize)
				break;
		}
		if (n_iov) {
1497 1498 1499 1500 1501 1502 1503 1504
			/* Search for a writable handle every time we call
			 * CIFSSMBWrite2.  We can't rely on the last handle
			 * we used to still be valid
			 */
			open_file = find_writable_file(CIFS_I(mapping->host));
			if (!open_file) {
				cERROR(1, ("No writable handles for inode"));
				rc = -EBADF;
S
Steve French 已提交
1505
			} else {
1506
				long_op = cifs_write_timeout(cifsi, offset);
1507 1508 1509 1510
				rc = CIFSSMBWrite2(xid, cifs_sb->tcon,
						   open_file->netfid,
						   bytes_to_write, offset,
						   &bytes_written, iov, n_iov,
1511
						   long_op);
1512
				cifsFileInfo_put(open_file);
1513 1514
				cifs_update_eof(cifsi, offset, bytes_written);

1515
				if (rc || bytes_written < bytes_to_write) {
1516
					cERROR(1, ("Write2 ret %d, wrote %d",
1517 1518 1519
						  rc, bytes_written));
					/* BB what if continued retry is
					   requested via mount flags? */
1520 1521 1522 1523
					if (rc == -ENOSPC)
						set_bit(AS_ENOSPC, &mapping->flags);
					else
						set_bit(AS_EIO, &mapping->flags);
1524 1525 1526 1527
				} else {
					cifs_stats_bytes_written(cifs_sb->tcon,
								 bytes_written);
				}
1528 1529 1530
			}
			for (i = 0; i < n_iov; i++) {
				page = pvec.pages[first + i];
1531 1532 1533 1534
				/* Should we also set page error on
				success rc but too little data written? */
				/* BB investigate retry logic on temporary
				server crash cases and how recovery works
S
Steve French 已提交
1535 1536
				when page marked as error */
				if (rc)
1537
					SetPageError(page);
1538 1539
				kunmap(page);
				unlock_page(page);
1540
				end_page_writeback(page);
1541 1542 1543 1544 1545
				page_cache_release(page);
			}
			if ((wbc->nr_to_write -= n_iov) <= 0)
				done = 1;
			index = next;
1546 1547 1548 1549
		} else
			/* Need to re-find the pages we skipped */
			index = pvec.pages[0]->index + 1;

1550 1551 1552 1553 1554 1555 1556 1557 1558 1559 1560
		pagevec_release(&pvec);
	}
	if (!scanned && !done) {
		/*
		 * We hit the last page and there is more work to be done: wrap
		 * back to the start of the file
		 */
		scanned = 1;
		index = 0;
		goto retry;
	}
1561
	if (wbc->range_cyclic || (range_whole && wbc->nr_to_write > 0))
1562 1563
		mapping->writeback_index = index;

L
Linus Torvalds 已提交
1564
	FreeXid(xid);
1565
	kfree(iov);
L
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1566 1567 1568
	return rc;
}

S
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1569
static int cifs_writepage(struct page *page, struct writeback_control *wbc)
L
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1570 1571 1572 1573 1574 1575 1576
{
	int rc = -EFAULT;
	int xid;

	xid = GetXid();
/* BB add check for wbc flags */
	page_cache_get(page);
S
Steve French 已提交
1577
	if (!PageUptodate(page))
L
Linus Torvalds 已提交
1578
		cFYI(1, ("ppw - page not up to date"));
1579 1580 1581 1582 1583 1584 1585 1586 1587 1588 1589

	/*
	 * Set the "writeback" flag, and clear "dirty" in the radix tree.
	 *
	 * A writepage() implementation always needs to do either this,
	 * or re-dirty the page with "redirty_page_for_writepage()" in
	 * the case of a failure.
	 *
	 * Just unlocking the page will cause the radix tree tag-bits
	 * to fail to update with the state of the page correctly.
	 */
S
Steve French 已提交
1590
	set_page_writeback(page);
L
Linus Torvalds 已提交
1591 1592 1593
	rc = cifs_partialpagewrite(page, 0, PAGE_CACHE_SIZE);
	SetPageUptodate(page); /* BB add check for error and Clearuptodate? */
	unlock_page(page);
1594 1595
	end_page_writeback(page);
	page_cache_release(page);
L
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1596 1597 1598 1599
	FreeXid(xid);
	return rc;
}

N
Nick Piggin 已提交
1600 1601 1602
static int cifs_write_end(struct file *file, struct address_space *mapping,
			loff_t pos, unsigned len, unsigned copied,
			struct page *page, void *fsdata)
L
Linus Torvalds 已提交
1603
{
N
Nick Piggin 已提交
1604 1605
	int rc;
	struct inode *inode = mapping->host;
L
Linus Torvalds 已提交
1606

N
Nick Piggin 已提交
1607 1608 1609
	cFYI(1, ("write_end for page %p from pos %lld with %d bytes",
		 page, pos, copied));

1610 1611 1612 1613 1614
	if (PageChecked(page)) {
		if (copied == len)
			SetPageUptodate(page);
		ClearPageChecked(page);
	} else if (!PageUptodate(page) && copied == PAGE_CACHE_SIZE)
N
Nick Piggin 已提交
1615
		SetPageUptodate(page);
S
Steve French 已提交
1616

L
Linus Torvalds 已提交
1617
	if (!PageUptodate(page)) {
N
Nick Piggin 已提交
1618 1619 1620 1621 1622
		char *page_data;
		unsigned offset = pos & (PAGE_CACHE_SIZE - 1);
		int xid;

		xid = GetXid();
L
Linus Torvalds 已提交
1623 1624 1625 1626 1627 1628
		/* this is probably better than directly calling
		   partialpage_write since in this function the file handle is
		   known which we might as well	leverage */
		/* BB check if anything else missing out of ppw
		   such as updating last write time */
		page_data = kmap(page);
N
Nick Piggin 已提交
1629 1630
		rc = cifs_write(file, page_data + offset, copied, &pos);
		/* if (rc < 0) should we set writebehind rc? */
L
Linus Torvalds 已提交
1631
		kunmap(page);
N
Nick Piggin 已提交
1632 1633

		FreeXid(xid);
S
Steve French 已提交
1634
	} else {
N
Nick Piggin 已提交
1635 1636
		rc = copied;
		pos += copied;
L
Linus Torvalds 已提交
1637 1638 1639
		set_page_dirty(page);
	}

N
Nick Piggin 已提交
1640 1641 1642 1643 1644 1645 1646 1647 1648 1649
	if (rc > 0) {
		spin_lock(&inode->i_lock);
		if (pos > inode->i_size)
			i_size_write(inode, pos);
		spin_unlock(&inode->i_lock);
	}

	unlock_page(page);
	page_cache_release(page);

L
Linus Torvalds 已提交
1650 1651 1652 1653 1654 1655 1656
	return rc;
}

int cifs_fsync(struct file *file, struct dentry *dentry, int datasync)
{
	int xid;
	int rc = 0;
1657 1658 1659
	struct cifsTconInfo *tcon;
	struct cifsFileInfo *smbfile =
		(struct cifsFileInfo *)file->private_data;
1660
	struct inode *inode = file->f_path.dentry->d_inode;
L
Linus Torvalds 已提交
1661 1662 1663

	xid = GetXid();

S
Steve French 已提交
1664
	cFYI(1, ("Sync file - name: %s datasync: 0x%x",
L
Linus Torvalds 已提交
1665
		dentry->d_name.name, datasync));
1666

1667 1668 1669
	rc = filemap_write_and_wait(inode->i_mapping);
	if (rc == 0) {
		rc = CIFS_I(inode)->write_behind_rc;
L
Linus Torvalds 已提交
1670
		CIFS_I(inode)->write_behind_rc = 0;
1671
		tcon = CIFS_SB(inode->i_sb)->tcon;
1672
		if (!rc && tcon && smbfile &&
S
Steve French 已提交
1673
		   !(CIFS_SB(inode->i_sb)->mnt_cifs_flags & CIFS_MOUNT_NOSSYNC))
1674
			rc = CIFSSMBFlush(xid, tcon, smbfile->netfid);
1675
	}
1676

L
Linus Torvalds 已提交
1677 1678 1679 1680
	FreeXid(xid);
	return rc;
}

1681
/* static void cifs_sync_page(struct page *page)
L
Linus Torvalds 已提交
1682 1683 1684 1685 1686 1687 1688 1689 1690 1691 1692 1693 1694
{
	struct address_space *mapping;
	struct inode *inode;
	unsigned long index = page->index;
	unsigned int rpages = 0;
	int rc = 0;

	cFYI(1, ("sync page %p",page));
	mapping = page->mapping;
	if (!mapping)
		return 0;
	inode = mapping->host;
	if (!inode)
1695
		return; */
L
Linus Torvalds 已提交
1696

S
Steve French 已提交
1697
/*	fill in rpages then
L
Linus Torvalds 已提交
1698 1699
	result = cifs_pagein_inode(inode, index, rpages); */ /* BB finish */

1700
/*	cFYI(1, ("rpages is %d for sync page of Index %ld", rpages, index));
L
Linus Torvalds 已提交
1701

1702
#if 0
L
Linus Torvalds 已提交
1703 1704 1705
	if (rc < 0)
		return rc;
	return 0;
1706
#endif
L
Linus Torvalds 已提交
1707 1708 1709 1710 1711 1712
} */

/*
 * As file closes, flush all cached write data for this inode checking
 * for write behind errors.
 */
1713
int cifs_flush(struct file *file, fl_owner_t id)
L
Linus Torvalds 已提交
1714
{
S
Steve French 已提交
1715
	struct inode *inode = file->f_path.dentry->d_inode;
L
Linus Torvalds 已提交
1716 1717 1718 1719 1720 1721 1722 1723 1724 1725 1726 1727
	int rc = 0;

	/* Rather than do the steps manually:
	   lock the inode for writing
	   loop through pages looking for write behind data (dirty pages)
	   coalesce into contiguous 16K (or smaller) chunks to write to server
	   send to server (prefer in parallel)
	   deal with writebehind errors
	   unlock inode for writing
	   filemapfdatawrite appears easier for the time being */

	rc = filemap_fdatawrite(inode->i_mapping);
1728 1729 1730
	/* reset wb rc if we were able to write out dirty pages */
	if (!rc) {
		rc = CIFS_I(inode)->write_behind_rc;
L
Linus Torvalds 已提交
1731
		CIFS_I(inode)->write_behind_rc = 0;
1732
	}
1733

S
Steve French 已提交
1734
	cFYI(1, ("Flush inode %p file %p rc %d", inode, file, rc));
L
Linus Torvalds 已提交
1735 1736 1737 1738 1739 1740 1741 1742 1743 1744 1745 1746 1747 1748 1749 1750 1751 1752 1753 1754

	return rc;
}

ssize_t cifs_user_read(struct file *file, char __user *read_data,
	size_t read_size, loff_t *poffset)
{
	int rc = -EACCES;
	unsigned int bytes_read = 0;
	unsigned int total_read = 0;
	unsigned int current_read_size;
	struct cifs_sb_info *cifs_sb;
	struct cifsTconInfo *pTcon;
	int xid;
	struct cifsFileInfo *open_file;
	char *smb_read_data;
	char __user *current_offset;
	struct smb_com_read_rsp *pSMBr;

	xid = GetXid();
1755
	cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
L
Linus Torvalds 已提交
1756 1757 1758
	pTcon = cifs_sb->tcon;

	if (file->private_data == NULL) {
1759
		rc = -EBADF;
L
Linus Torvalds 已提交
1760
		FreeXid(xid);
1761
		return rc;
L
Linus Torvalds 已提交
1762 1763 1764
	}
	open_file = (struct cifsFileInfo *)file->private_data;

S
Steve French 已提交
1765
	if ((file->f_flags & O_ACCMODE) == O_WRONLY)
L
Linus Torvalds 已提交
1766
		cFYI(1, ("attempting read on write only file instance"));
S
Steve French 已提交
1767

L
Linus Torvalds 已提交
1768 1769 1770
	for (total_read = 0, current_offset = read_data;
	     read_size > total_read;
	     total_read += bytes_read, current_offset += bytes_read) {
S
Steve French 已提交
1771
		current_read_size = min_t(const int, read_size - total_read,
L
Linus Torvalds 已提交
1772 1773 1774 1775
					  cifs_sb->rsize);
		rc = -EAGAIN;
		smb_read_data = NULL;
		while (rc == -EAGAIN) {
1776
			int buf_type = CIFS_NO_BUFFER;
S
Steve French 已提交
1777
			if ((open_file->invalidHandle) &&
L
Linus Torvalds 已提交
1778
			    (!open_file->closePend)) {
1779
				rc = cifs_reopen_file(file, true);
L
Linus Torvalds 已提交
1780 1781 1782
				if (rc != 0)
					break;
			}
1783
			rc = CIFSSMBRead(xid, pTcon,
1784 1785 1786 1787
					 open_file->netfid,
					 current_read_size, *poffset,
					 &bytes_read, &smb_read_data,
					 &buf_type);
L
Linus Torvalds 已提交
1788 1789
			pSMBr = (struct smb_com_read_rsp *)smb_read_data;
			if (smb_read_data) {
1790 1791 1792 1793
				if (copy_to_user(current_offset,
						smb_read_data +
						4 /* RFC1001 length field */ +
						le16_to_cpu(pSMBr->DataOffset),
S
Steve French 已提交
1794
						bytes_read))
1795 1796
					rc = -EFAULT;

S
Steve French 已提交
1797
				if (buf_type == CIFS_SMALL_BUFFER)
1798
					cifs_small_buf_release(smb_read_data);
S
Steve French 已提交
1799
				else if (buf_type == CIFS_LARGE_BUFFER)
1800
					cifs_buf_release(smb_read_data);
L
Linus Torvalds 已提交
1801 1802 1803 1804 1805 1806 1807 1808 1809 1810 1811
				smb_read_data = NULL;
			}
		}
		if (rc || (bytes_read == 0)) {
			if (total_read) {
				break;
			} else {
				FreeXid(xid);
				return rc;
			}
		} else {
1812
			cifs_stats_bytes_read(pTcon, bytes_read);
L
Linus Torvalds 已提交
1813 1814 1815 1816 1817 1818 1819 1820 1821 1822 1823 1824 1825 1826 1827 1828 1829 1830 1831 1832
			*poffset += bytes_read;
		}
	}
	FreeXid(xid);
	return total_read;
}


static ssize_t cifs_read(struct file *file, char *read_data, size_t read_size,
	loff_t *poffset)
{
	int rc = -EACCES;
	unsigned int bytes_read = 0;
	unsigned int total_read;
	unsigned int current_read_size;
	struct cifs_sb_info *cifs_sb;
	struct cifsTconInfo *pTcon;
	int xid;
	char *current_offset;
	struct cifsFileInfo *open_file;
1833
	int buf_type = CIFS_NO_BUFFER;
L
Linus Torvalds 已提交
1834 1835

	xid = GetXid();
1836
	cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
L
Linus Torvalds 已提交
1837 1838 1839
	pTcon = cifs_sb->tcon;

	if (file->private_data == NULL) {
1840
		rc = -EBADF;
L
Linus Torvalds 已提交
1841
		FreeXid(xid);
1842
		return rc;
L
Linus Torvalds 已提交
1843 1844 1845 1846 1847 1848
	}
	open_file = (struct cifsFileInfo *)file->private_data;

	if ((file->f_flags & O_ACCMODE) == O_WRONLY)
		cFYI(1, ("attempting read on write only file instance"));

S
Steve French 已提交
1849
	for (total_read = 0, current_offset = read_data;
L
Linus Torvalds 已提交
1850 1851 1852 1853
	     read_size > total_read;
	     total_read += bytes_read, current_offset += bytes_read) {
		current_read_size = min_t(const int, read_size - total_read,
					  cifs_sb->rsize);
1854 1855
		/* For windows me and 9x we do not want to request more
		than it negotiated since it will refuse the read then */
S
Steve French 已提交
1856
		if ((pTcon->ses) &&
1857 1858 1859 1860
			!(pTcon->ses->capabilities & CAP_LARGE_FILES)) {
			current_read_size = min_t(const int, current_read_size,
					pTcon->ses->server->maxBuf - 128);
		}
L
Linus Torvalds 已提交
1861 1862
		rc = -EAGAIN;
		while (rc == -EAGAIN) {
S
Steve French 已提交
1863
			if ((open_file->invalidHandle) &&
L
Linus Torvalds 已提交
1864
			    (!open_file->closePend)) {
1865
				rc = cifs_reopen_file(file, true);
L
Linus Torvalds 已提交
1866 1867 1868
				if (rc != 0)
					break;
			}
1869
			rc = CIFSSMBRead(xid, pTcon,
1870 1871 1872 1873
					 open_file->netfid,
					 current_read_size, *poffset,
					 &bytes_read, &current_offset,
					 &buf_type);
L
Linus Torvalds 已提交
1874 1875 1876 1877 1878 1879 1880 1881 1882
		}
		if (rc || (bytes_read == 0)) {
			if (total_read) {
				break;
			} else {
				FreeXid(xid);
				return rc;
			}
		} else {
1883
			cifs_stats_bytes_read(pTcon, total_read);
L
Linus Torvalds 已提交
1884 1885 1886 1887 1888 1889 1890 1891 1892
			*poffset += bytes_read;
		}
	}
	FreeXid(xid);
	return total_read;
}

int cifs_file_mmap(struct file *file, struct vm_area_struct *vma)
{
1893
	struct dentry *dentry = file->f_path.dentry;
L
Linus Torvalds 已提交
1894 1895 1896 1897 1898 1899 1900 1901 1902 1903 1904 1905 1906 1907 1908
	int rc, xid;

	xid = GetXid();
	rc = cifs_revalidate(dentry);
	if (rc) {
		cFYI(1, ("Validation prior to mmap failed, error=%d", rc));
		FreeXid(xid);
		return rc;
	}
	rc = generic_file_mmap(file, vma);
	FreeXid(xid);
	return rc;
}


S
Steve French 已提交
1909
static void cifs_copy_cache_pages(struct address_space *mapping,
L
Linus Torvalds 已提交
1910 1911 1912 1913 1914 1915 1916 1917 1918 1919 1920 1921 1922 1923 1924 1925 1926
	struct list_head *pages, int bytes_read, char *data,
	struct pagevec *plru_pvec)
{
	struct page *page;
	char *target;

	while (bytes_read > 0) {
		if (list_empty(pages))
			break;

		page = list_entry(pages->prev, struct page, lru);
		list_del(&page->lru);

		if (add_to_page_cache(page, mapping, page->index,
				      GFP_KERNEL)) {
			page_cache_release(page);
			cFYI(1, ("Add page cache failed"));
1927 1928
			data += PAGE_CACHE_SIZE;
			bytes_read -= PAGE_CACHE_SIZE;
L
Linus Torvalds 已提交
1929 1930 1931
			continue;
		}

S
Steve French 已提交
1932
		target = kmap_atomic(page, KM_USER0);
L
Linus Torvalds 已提交
1933 1934 1935 1936

		if (PAGE_CACHE_SIZE > bytes_read) {
			memcpy(target, data, bytes_read);
			/* zero the tail end of this partial page */
S
Steve French 已提交
1937
			memset(target + bytes_read, 0,
L
Linus Torvalds 已提交
1938 1939 1940 1941 1942 1943 1944 1945 1946 1947 1948 1949
			       PAGE_CACHE_SIZE - bytes_read);
			bytes_read = 0;
		} else {
			memcpy(target, data, PAGE_CACHE_SIZE);
			bytes_read -= PAGE_CACHE_SIZE;
		}
		kunmap_atomic(target, KM_USER0);

		flush_dcache_page(page);
		SetPageUptodate(page);
		unlock_page(page);
		if (!pagevec_add(plru_pvec, page))
1950
			__pagevec_lru_add_file(plru_pvec);
L
Linus Torvalds 已提交
1951 1952 1953 1954 1955 1956 1957 1958 1959 1960 1961 1962 1963 1964
		data += PAGE_CACHE_SIZE;
	}
	return;
}

static int cifs_readpages(struct file *file, struct address_space *mapping,
	struct list_head *page_list, unsigned num_pages)
{
	int rc = -EACCES;
	int xid;
	loff_t offset;
	struct page *page;
	struct cifs_sb_info *cifs_sb;
	struct cifsTconInfo *pTcon;
S
Steve French 已提交
1965
	unsigned int bytes_read = 0;
S
Steve French 已提交
1966
	unsigned int read_size, i;
L
Linus Torvalds 已提交
1967 1968 1969 1970
	char *smb_read_data = NULL;
	struct smb_com_read_rsp *pSMBr;
	struct pagevec lru_pvec;
	struct cifsFileInfo *open_file;
1971
	int buf_type = CIFS_NO_BUFFER;
L
Linus Torvalds 已提交
1972 1973 1974

	xid = GetXid();
	if (file->private_data == NULL) {
1975
		rc = -EBADF;
L
Linus Torvalds 已提交
1976
		FreeXid(xid);
1977
		return rc;
L
Linus Torvalds 已提交
1978 1979
	}
	open_file = (struct cifsFileInfo *)file->private_data;
1980
	cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
L
Linus Torvalds 已提交
1981
	pTcon = cifs_sb->tcon;
1982

L
Linus Torvalds 已提交
1983
	pagevec_init(&lru_pvec, 0);
S
Steve French 已提交
1984
	cFYI(DBG2, ("rpages: num pages %d", num_pages));
L
Linus Torvalds 已提交
1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997
	for (i = 0; i < num_pages; ) {
		unsigned contig_pages;
		struct page *tmp_page;
		unsigned long expected_index;

		if (list_empty(page_list))
			break;

		page = list_entry(page_list->prev, struct page, lru);
		offset = (loff_t)page->index << PAGE_CACHE_SHIFT;

		/* count adjacent pages that we will read into */
		contig_pages = 0;
S
Steve French 已提交
1998
		expected_index =
L
Linus Torvalds 已提交
1999
			list_entry(page_list->prev, struct page, lru)->index;
S
Steve French 已提交
2000
		list_for_each_entry_reverse(tmp_page, page_list, lru) {
L
Linus Torvalds 已提交
2001 2002 2003 2004
			if (tmp_page->index == expected_index) {
				contig_pages++;
				expected_index++;
			} else
S
Steve French 已提交
2005
				break;
L
Linus Torvalds 已提交
2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016
		}
		if (contig_pages + i >  num_pages)
			contig_pages = num_pages - i;

		/* for reads over a certain size could initiate async
		   read ahead */

		read_size = contig_pages * PAGE_CACHE_SIZE;
		/* Read size needs to be in multiples of one page */
		read_size = min_t(const unsigned int, read_size,
				  cifs_sb->rsize & PAGE_CACHE_MASK);
2017
		cFYI(DBG2, ("rpages: read size 0x%x  contiguous pages %d",
2018
				read_size, contig_pages));
L
Linus Torvalds 已提交
2019 2020
		rc = -EAGAIN;
		while (rc == -EAGAIN) {
S
Steve French 已提交
2021
			if ((open_file->invalidHandle) &&
L
Linus Torvalds 已提交
2022
			    (!open_file->closePend)) {
2023
				rc = cifs_reopen_file(file, true);
L
Linus Torvalds 已提交
2024 2025 2026 2027
				if (rc != 0)
					break;
			}

2028
			rc = CIFSSMBRead(xid, pTcon,
2029 2030 2031 2032
					 open_file->netfid,
					 read_size, offset,
					 &bytes_read, &smb_read_data,
					 &buf_type);
2033
			/* BB more RC checks ? */
S
Steve French 已提交
2034
			if (rc == -EAGAIN) {
L
Linus Torvalds 已提交
2035
				if (smb_read_data) {
S
Steve French 已提交
2036
					if (buf_type == CIFS_SMALL_BUFFER)
2037
						cifs_small_buf_release(smb_read_data);
S
Steve French 已提交
2038
					else if (buf_type == CIFS_LARGE_BUFFER)
2039
						cifs_buf_release(smb_read_data);
L
Linus Torvalds 已提交
2040 2041 2042 2043 2044 2045 2046 2047
					smb_read_data = NULL;
				}
			}
		}
		if ((rc < 0) || (smb_read_data == NULL)) {
			cFYI(1, ("Read error in readpages: %d", rc));
			break;
		} else if (bytes_read > 0) {
2048
			task_io_account_read(bytes_read);
L
Linus Torvalds 已提交
2049 2050 2051 2052 2053 2054
			pSMBr = (struct smb_com_read_rsp *)smb_read_data;
			cifs_copy_cache_pages(mapping, page_list, bytes_read,
				smb_read_data + 4 /* RFC1001 hdr */ +
				le16_to_cpu(pSMBr->DataOffset), &lru_pvec);

			i +=  bytes_read >> PAGE_CACHE_SHIFT;
2055
			cifs_stats_bytes_read(pTcon, bytes_read);
S
Steve French 已提交
2056
			if ((bytes_read & PAGE_CACHE_MASK) != bytes_read) {
L
Linus Torvalds 已提交
2057 2058
				i++; /* account for partial page */

S
Steve French 已提交
2059
				/* server copy of file can have smaller size
L
Linus Torvalds 已提交
2060
				   than client */
S
Steve French 已提交
2061 2062
				/* BB do we need to verify this common case ?
				   this case is ok - if we are at server EOF
L
Linus Torvalds 已提交
2063 2064
				   we will hit it on next read */

O
OGAWA Hirofumi 已提交
2065
				/* break; */
L
Linus Torvalds 已提交
2066 2067 2068 2069 2070
			}
		} else {
			cFYI(1, ("No bytes read (%d) at offset %lld . "
				 "Cleaning remaining pages from readahead list",
				 bytes_read, offset));
S
Steve French 已提交
2071
			/* BB turn off caching and do new lookup on
L
Linus Torvalds 已提交
2072 2073 2074 2075
			   file size at server? */
			break;
		}
		if (smb_read_data) {
S
Steve French 已提交
2076
			if (buf_type == CIFS_SMALL_BUFFER)
2077
				cifs_small_buf_release(smb_read_data);
S
Steve French 已提交
2078
			else if (buf_type == CIFS_LARGE_BUFFER)
2079
				cifs_buf_release(smb_read_data);
L
Linus Torvalds 已提交
2080 2081 2082 2083 2084
			smb_read_data = NULL;
		}
		bytes_read = 0;
	}

2085
	pagevec_lru_add_file(&lru_pvec);
L
Linus Torvalds 已提交
2086 2087 2088

/* need to free smb_read_data buf before exit */
	if (smb_read_data) {
S
Steve French 已提交
2089
		if (buf_type == CIFS_SMALL_BUFFER)
2090
			cifs_small_buf_release(smb_read_data);
S
Steve French 已提交
2091
		else if (buf_type == CIFS_LARGE_BUFFER)
2092
			cifs_buf_release(smb_read_data);
L
Linus Torvalds 已提交
2093
		smb_read_data = NULL;
S
Steve French 已提交
2094
	}
L
Linus Torvalds 已提交
2095 2096 2097 2098 2099 2100 2101 2102 2103 2104 2105 2106 2107 2108

	FreeXid(xid);
	return rc;
}

static int cifs_readpage_worker(struct file *file, struct page *page,
	loff_t *poffset)
{
	char *read_data;
	int rc;

	page_cache_get(page);
	read_data = kmap(page);
	/* for reads over a certain size could initiate async read ahead */
S
Steve French 已提交
2109

L
Linus Torvalds 已提交
2110
	rc = cifs_read(file, read_data, PAGE_CACHE_SIZE, poffset);
S
Steve French 已提交
2111

L
Linus Torvalds 已提交
2112 2113 2114
	if (rc < 0)
		goto io_error;
	else
S
Steve French 已提交
2115 2116
		cFYI(1, ("Bytes read %d", rc));

2117 2118
	file->f_path.dentry->d_inode->i_atime =
		current_fs_time(file->f_path.dentry->d_inode->i_sb);
S
Steve French 已提交
2119

L
Linus Torvalds 已提交
2120 2121 2122 2123 2124 2125
	if (PAGE_CACHE_SIZE > rc)
		memset(read_data + rc, 0, PAGE_CACHE_SIZE - rc);

	flush_dcache_page(page);
	SetPageUptodate(page);
	rc = 0;
S
Steve French 已提交
2126

L
Linus Torvalds 已提交
2127
io_error:
S
Steve French 已提交
2128
	kunmap(page);
L
Linus Torvalds 已提交
2129 2130 2131 2132 2133 2134 2135 2136 2137 2138 2139 2140 2141
	page_cache_release(page);
	return rc;
}

static int cifs_readpage(struct file *file, struct page *page)
{
	loff_t offset = (loff_t)page->index << PAGE_CACHE_SHIFT;
	int rc = -EACCES;
	int xid;

	xid = GetXid();

	if (file->private_data == NULL) {
2142
		rc = -EBADF;
L
Linus Torvalds 已提交
2143
		FreeXid(xid);
2144
		return rc;
L
Linus Torvalds 已提交
2145 2146
	}

S
Steve French 已提交
2147
	cFYI(1, ("readpage %p at offset %d 0x%x\n",
L
Linus Torvalds 已提交
2148 2149 2150 2151 2152 2153 2154 2155 2156 2157
		 page, (int)offset, (int)offset));

	rc = cifs_readpage_worker(file, page, &offset);

	unlock_page(page);

	FreeXid(xid);
	return rc;
}

2158 2159 2160 2161 2162 2163 2164 2165 2166 2167 2168 2169 2170 2171 2172 2173 2174 2175 2176
static int is_inode_writable(struct cifsInodeInfo *cifs_inode)
{
	struct cifsFileInfo *open_file;

	read_lock(&GlobalSMBSeslock);
	list_for_each_entry(open_file, &cifs_inode->openFileList, flist) {
		if (open_file->closePend)
			continue;
		if (open_file->pfile &&
		    ((open_file->pfile->f_flags & O_RDWR) ||
		     (open_file->pfile->f_flags & O_WRONLY))) {
			read_unlock(&GlobalSMBSeslock);
			return 1;
		}
	}
	read_unlock(&GlobalSMBSeslock);
	return 0;
}

L
Linus Torvalds 已提交
2177 2178 2179
/* We do not want to update the file size from server for inodes
   open for write - to avoid races with writepage extending
   the file - in the future we could consider allowing
S
Steve French 已提交
2180
   refreshing the inode only on increases in the file size
L
Linus Torvalds 已提交
2181 2182
   but this is tricky to do without racing with writebehind
   page caching in the current Linux kernel design */
2183
bool is_size_safe_to_change(struct cifsInodeInfo *cifsInode, __u64 end_of_file)
L
Linus Torvalds 已提交
2184
{
2185
	if (!cifsInode)
2186
		return true;
2187

2188 2189
	if (is_inode_writable(cifsInode)) {
		/* This inode is open for write at least once */
2190 2191 2192
		struct cifs_sb_info *cifs_sb;

		cifs_sb = CIFS_SB(cifsInode->vfs_inode.i_sb);
S
Steve French 已提交
2193
		if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_DIRECT_IO) {
S
Steve French 已提交
2194
			/* since no page cache to corrupt on directio
2195
			we can change size safely */
2196
			return true;
2197 2198
		}

S
Steve French 已提交
2199
		if (i_size_read(&cifsInode->vfs_inode) < end_of_file)
2200
			return true;
2201

2202
		return false;
2203
	} else
2204
		return true;
L
Linus Torvalds 已提交
2205 2206
}

N
Nick Piggin 已提交
2207 2208 2209
static int cifs_write_begin(struct file *file, struct address_space *mapping,
			loff_t pos, unsigned len, unsigned flags,
			struct page **pagep, void **fsdata)
L
Linus Torvalds 已提交
2210
{
N
Nick Piggin 已提交
2211 2212
	pgoff_t index = pos >> PAGE_CACHE_SHIFT;
	loff_t offset = pos & (PAGE_CACHE_SIZE - 1);
2213 2214 2215 2216
	loff_t page_start = pos & PAGE_MASK;
	loff_t i_size;
	struct page *page;
	int rc = 0;
N
Nick Piggin 已提交
2217 2218 2219

	cFYI(1, ("write_begin from %lld len %d", (long long)pos, len));

2220
	page = grab_cache_page_write_begin(mapping, index, flags);
2221 2222 2223 2224
	if (!page) {
		rc = -ENOMEM;
		goto out;
	}
2225

2226 2227
	if (PageUptodate(page))
		goto out;
2228

2229 2230 2231 2232 2233 2234 2235
	/*
	 * If we write a full page it will be up to date, no need to read from
	 * the server. If the write is short, we'll end up doing a sync write
	 * instead.
	 */
	if (len == PAGE_CACHE_SIZE)
		goto out;
2236

2237 2238 2239 2240 2241 2242 2243 2244 2245 2246 2247 2248 2249 2250 2251 2252 2253 2254 2255 2256 2257 2258 2259
	/*
	 * optimize away the read when we have an oplock, and we're not
	 * expecting to use any of the data we'd be reading in. That
	 * is, when the page lies beyond the EOF, or straddles the EOF
	 * and the write will cover all of the existing data.
	 */
	if (CIFS_I(mapping->host)->clientCanCacheRead) {
		i_size = i_size_read(mapping->host);
		if (page_start >= i_size ||
		    (offset == 0 && (pos + len) >= i_size)) {
			zero_user_segments(page, 0, offset,
					   offset + len,
					   PAGE_CACHE_SIZE);
			/*
			 * PageChecked means that the parts of the page
			 * to which we're not writing are considered up
			 * to date. Once the data is copied to the
			 * page, it can be set uptodate.
			 */
			SetPageChecked(page);
			goto out;
		}
	}
N
Nick Piggin 已提交
2260

2261 2262 2263 2264 2265 2266 2267
	if ((file->f_flags & O_ACCMODE) != O_WRONLY) {
		/*
		 * might as well read a page, it is fast enough. If we get
		 * an error, we don't need to return it. cifs_write_end will
		 * do a sync write instead since PG_uptodate isn't set.
		 */
		cifs_readpage_worker(file, page, &page_start);
2268 2269 2270 2271
	} else {
		/* we could try using another file handle if there is one -
		   but how would we lock it to prevent close of that handle
		   racing with this read? In any case
N
Nick Piggin 已提交
2272
		   this will be written out by write_end so is fine */
L
Linus Torvalds 已提交
2273
	}
2274 2275 2276
out:
	*pagep = page;
	return rc;
L
Linus Torvalds 已提交
2277 2278
}

2279 2280 2281 2282 2283 2284 2285 2286 2287 2288 2289 2290 2291 2292 2293 2294 2295 2296 2297 2298 2299 2300 2301 2302 2303 2304 2305 2306 2307 2308 2309 2310 2311 2312 2313 2314 2315 2316 2317 2318 2319 2320 2321 2322 2323 2324 2325 2326 2327 2328 2329 2330 2331 2332 2333 2334 2335 2336 2337 2338 2339 2340 2341 2342 2343 2344 2345
static void
cifs_oplock_break(struct slow_work *work)
{
	struct cifsFileInfo *cfile = container_of(work, struct cifsFileInfo,
						  oplock_break);
	struct inode *inode = cfile->pInode;
	struct cifsInodeInfo *cinode = CIFS_I(inode);
	struct cifs_sb_info *cifs_sb = CIFS_SB(cfile->mnt->mnt_sb);
	int rc, waitrc = 0;

	if (inode && S_ISREG(inode->i_mode)) {
#ifdef CONFIG_CIFS_EXPERIMENTAL
		if (cinode->clientCanCacheAll == 0)
			break_lease(inode, FMODE_READ);
		else if (cinode->clientCanCacheRead == 0)
			break_lease(inode, FMODE_WRITE);
#endif
		rc = filemap_fdatawrite(inode->i_mapping);
		if (cinode->clientCanCacheRead == 0) {
			waitrc = filemap_fdatawait(inode->i_mapping);
			invalidate_remote_inode(inode);
		}
		if (!rc)
			rc = waitrc;
		if (rc)
			cinode->write_behind_rc = rc;
		cFYI(1, ("Oplock flush inode %p rc %d", inode, rc));
	}

	/*
	 * releasing stale oplock after recent reconnect of smb session using
	 * a now incorrect file handle is not a data integrity issue but do
	 * not bother sending an oplock release if session to server still is
	 * disconnected since oplock already released by the server
	 */
	if (!cfile->closePend && !cfile->oplock_break_cancelled) {
		rc = CIFSSMBLock(0, cifs_sb->tcon, cfile->netfid, 0, 0, 0, 0,
				 LOCKING_ANDX_OPLOCK_RELEASE, false);
		cFYI(1, ("Oplock release rc = %d", rc));
	}
}

static int
cifs_oplock_break_get(struct slow_work *work)
{
	struct cifsFileInfo *cfile = container_of(work, struct cifsFileInfo,
						  oplock_break);
	mntget(cfile->mnt);
	cifsFileInfo_get(cfile);
	return 0;
}

static void
cifs_oplock_break_put(struct slow_work *work)
{
	struct cifsFileInfo *cfile = container_of(work, struct cifsFileInfo,
						  oplock_break);
	mntput(cfile->mnt);
	cifsFileInfo_put(cfile);
}

const struct slow_work_ops cifs_oplock_break_ops = {
	.get_ref	= cifs_oplock_break_get,
	.put_ref	= cifs_oplock_break_put,
	.execute	= cifs_oplock_break,
};

2346
const struct address_space_operations cifs_addr_ops = {
L
Linus Torvalds 已提交
2347 2348 2349
	.readpage = cifs_readpage,
	.readpages = cifs_readpages,
	.writepage = cifs_writepage,
2350
	.writepages = cifs_writepages,
N
Nick Piggin 已提交
2351 2352
	.write_begin = cifs_write_begin,
	.write_end = cifs_write_end,
L
Linus Torvalds 已提交
2353 2354 2355 2356
	.set_page_dirty = __set_page_dirty_nobuffers,
	/* .sync_page = cifs_sync_page, */
	/* .direct_IO = */
};
D
Dave Kleikamp 已提交
2357 2358 2359 2360 2361 2362

/*
 * cifs_readpages requires the server to support a buffer large enough to
 * contain the header plus one complete page of data.  Otherwise, we need
 * to leave cifs_readpages out of the address space operations.
 */
2363
const struct address_space_operations cifs_addr_ops_smallbuf = {
D
Dave Kleikamp 已提交
2364 2365 2366
	.readpage = cifs_readpage,
	.writepage = cifs_writepage,
	.writepages = cifs_writepages,
N
Nick Piggin 已提交
2367 2368
	.write_begin = cifs_write_begin,
	.write_end = cifs_write_end,
D
Dave Kleikamp 已提交
2369 2370 2371 2372
	.set_page_dirty = __set_page_dirty_nobuffers,
	/* .sync_page = cifs_sync_page, */
	/* .direct_IO = */
};