file.c 64.6 KB
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/*
 *   fs/cifs/file.c
 *
 *   vfs operations that deal with files
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 *
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 *   Copyright (C) International Business Machines  Corp., 2002,2010
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 *   Author(s): Steve French (sfrench@us.ibm.com)
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[CIFS]  
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 <linux/slab.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,
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			     struct cifsInodeInfo *pCifsInode, __u32 oplock,
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			     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))) {
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		cFYI(1, "inode unchanged on server");
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	} 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;
		}
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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);
	} */

psx_client_can_cache:
	if ((oplock & 0xF) == OPLOCK_EXCLUSIVE) {
		pCifsInode->clientCanCacheAll = true;
		pCifsInode->clientCanCacheRead = true;
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		cFYI(1, "Exclusive Oplock granted on inode %p",
			 file->f_path.dentry->d_inode);
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	} 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))
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			cERROR(1, "could not find file instance for "
				   "new file %p", file);
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	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))) {
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		cFYI(1, "inode unchanged on server");
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	} 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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		}
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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",
			 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",
		 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);
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		oflags |= SMB_O_CREAT;
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		/* 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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				inode->i_sb,
				cifs_sb->mnt_file_mode /* ignored */,
				oflags, &oplock, &netfid, xid);
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		if (rc == 0) {
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			cFYI(1, "posix open succeeded");
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			/* 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,
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						     oplock, netfid);
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			goto out;
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		} else if ((rc == -EINVAL) || (rc == -EOPNOTSUPP)) {
			if (tcon->ses->serverNOS)
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				cERROR(1, "server %s of type %s returned"
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					   " unexpected error on SMB posix open"
					   ", disabling posix open support."
					   " Check if server update available.",
					   tcon->ses->serverName,
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					   tcon->ses->serverNOS);
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			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");
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		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");
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		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",
		 inode, file->f_flags, full_path);
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505 506 507 508

	if (oplockEnabled)
		oplock = REQ_OPLOCK;
	else
509
		oplock = 0;
L
Linus Torvalds 已提交
510

511 512 513 514 515
	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 */
516
		rc = cifs_posix_open(full_path, NULL, file->f_path.mnt,
517 518 519
				inode->i_sb,
				cifs_sb->mnt_file_mode /* ignored */,
				oflags, &oplock, &netfid, xid);
520
		if (rc == 0) {
521
			cFYI(1, "posix reopen succeeded");
522 523 524 525 526 527 528 529
			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
530
	/* Can not refresh inode by passing in file_info buf to be returned
S
Steve French 已提交
531 532
	   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
533 534 535
	   and server version of file size can be stale. If we knew for sure
	   that inode was not dirty locally we could do this */

536
	rc = CIFSSMBOpen(xid, tcon, full_path, disposition, desiredAccess,
L
Linus Torvalds 已提交
537
			 CREATE_NOT_DIR, &netfid, &oplock, NULL,
S
Steve French 已提交
538
			 cifs_sb->local_nls, cifs_sb->mnt_cifs_flags &
539
				CIFS_MOUNT_MAP_SPECIAL_CHR);
L
Linus Torvalds 已提交
540
	if (rc) {
541
		mutex_unlock(&pCifsFile->fh_mutex);
542 543
		cFYI(1, "cifs_open returned 0x%x", rc);
		cFYI(1, "oplock: %d", oplock);
L
Linus Torvalds 已提交
544
	} else {
545
reopen_success:
L
Linus Torvalds 已提交
546
		pCifsFile->netfid = netfid;
547
		pCifsFile->invalidHandle = false;
548
		mutex_unlock(&pCifsFile->fh_mutex);
L
Linus Torvalds 已提交
549 550 551
		pCifsInode = CIFS_I(inode);
		if (pCifsInode) {
			if (can_flush) {
552 553 554
				rc = filemap_write_and_wait(inode->i_mapping);
				if (rc != 0)
					CIFS_I(inode)->write_behind_rc = rc;
L
Linus Torvalds 已提交
555 556
			/* temporarily disable caching while we
			   go to server to get inode info */
557 558
				pCifsInode->clientCanCacheAll = false;
				pCifsInode->clientCanCacheRead = false;
559
				if (tcon->unix_ext)
L
Linus Torvalds 已提交
560 561 562 563 564
					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,
565
						xid, NULL);
L
Linus Torvalds 已提交
566 567 568 569 570 571 572
			} /* 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) {
573 574
				pCifsInode->clientCanCacheAll = true;
				pCifsInode->clientCanCacheRead = true;
575 576
				cFYI(1, "Exclusive Oplock granted on inode %p",
					 file->f_path.dentry->d_inode);
L
Linus Torvalds 已提交
577
			} else if ((oplock & 0xF) == OPLOCK_READ) {
578 579
				pCifsInode->clientCanCacheRead = true;
				pCifsInode->clientCanCacheAll = false;
L
Linus Torvalds 已提交
580
			} else {
581 582
				pCifsInode->clientCanCacheRead = false;
				pCifsInode->clientCanCacheAll = false;
L
Linus Torvalds 已提交
583 584 585 586 587 588 589 590 591 592 593 594
			}
			cifs_relock_file(pCifsFile);
		}
	}
	kfree(full_path);
	FreeXid(xid);
	return rc;
}

int cifs_close(struct inode *inode, struct file *file)
{
	int rc = 0;
595
	int xid, timeout;
L
Linus Torvalds 已提交
596 597 598 599 600 601 602 603 604 605
	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
606
		struct cifsLockInfo *li, *tmp;
607
		write_lock(&GlobalSMBSeslock);
608
		pSMBFile->closePend = true;
L
Linus Torvalds 已提交
609 610 611
		if (pTcon) {
			/* no sense reconnecting to close a file that is
			   already closed */
S
Steve French 已提交
612
			if (!pTcon->need_reconnect) {
613
				write_unlock(&GlobalSMBSeslock);
614
				timeout = 2;
615
				while ((atomic_read(&pSMBFile->count) != 1)
616
					&& (timeout <= 2048)) {
617 618 619 620 621
					/* 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
622
					but this should give enough time to
623
					clear the socket */
624
					cFYI(DBG2, "close delay, write pending");
625 626
					msleep(timeout);
					timeout *= 4;
627
				}
628 629 630
				if (!pTcon->need_reconnect &&
				    !pSMBFile->invalidHandle)
					rc = CIFSSMBClose(xid, pTcon,
L
Linus Torvalds 已提交
631
						  pSMBFile->netfid);
632 633 634 635
			} else
				write_unlock(&GlobalSMBSeslock);
		} else
			write_unlock(&GlobalSMBSeslock);
J
[CIFS]  
Jeremy Allison 已提交
636 637 638

		/* Delete any outstanding lock records.
		   We'll lose them when the file is closed anyway. */
639
		mutex_lock(&pSMBFile->lock_mutex);
J
[CIFS]  
Jeremy Allison 已提交
640 641 642 643
		list_for_each_entry_safe(li, tmp, &pSMBFile->llist, llist) {
			list_del(&li->llist);
			kfree(li);
		}
644
		mutex_unlock(&pSMBFile->lock_mutex);
J
[CIFS]  
Jeremy Allison 已提交
645

646
		write_lock(&GlobalSMBSeslock);
L
Linus Torvalds 已提交
647 648
		list_del(&pSMBFile->flist);
		list_del(&pSMBFile->tlist);
649
		write_unlock(&GlobalSMBSeslock);
650
		cifsFileInfo_put(file->private_data);
L
Linus Torvalds 已提交
651 652 653 654
		file->private_data = NULL;
	} else
		rc = -EBADF;

655
	read_lock(&GlobalSMBSeslock);
L
Linus Torvalds 已提交
656
	if (list_empty(&(CIFS_I(inode)->openFileList))) {
657
		cFYI(1, "closing last open instance for inode %p", inode);
L
Linus Torvalds 已提交
658 659
		/* 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 */
660 661
		CIFS_I(inode)->clientCanCacheRead = false;
		CIFS_I(inode)->clientCanCacheAll  = false;
L
Linus Torvalds 已提交
662
	}
663
	read_unlock(&GlobalSMBSeslock);
S
Steve French 已提交
664
	if ((rc == 0) && CIFS_I(inode)->write_behind_rc)
L
Linus Torvalds 已提交
665 666 667 668 669 670 671 672 673 674 675 676 677
		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;

678
	cFYI(1, "Closedir inode = 0x%p", inode);
L
Linus Torvalds 已提交
679 680 681 682 683

	xid = GetXid();

	if (pCFileStruct) {
		struct cifsTconInfo *pTcon;
S
Steve French 已提交
684 685
		struct cifs_sb_info *cifs_sb =
			CIFS_SB(file->f_path.dentry->d_sb);
L
Linus Torvalds 已提交
686 687 688

		pTcon = cifs_sb->tcon;

689
		cFYI(1, "Freeing private data in close dir");
690
		write_lock(&GlobalSMBSeslock);
691 692 693
		if (!pCFileStruct->srch_inf.endOfSearch &&
		    !pCFileStruct->invalidHandle) {
			pCFileStruct->invalidHandle = true;
694
			write_unlock(&GlobalSMBSeslock);
L
Linus Torvalds 已提交
695
			rc = CIFSFindClose(xid, pTcon, pCFileStruct->netfid);
696 697
			cFYI(1, "Closing uncompleted readdir with rc %d",
				 rc);
L
Linus Torvalds 已提交
698 699
			/* not much we can do if it fails anyway, ignore rc */
			rc = 0;
700 701
		} else
			write_unlock(&GlobalSMBSeslock);
L
Linus Torvalds 已提交
702 703
		ptmp = pCFileStruct->srch_inf.ntwrk_buf_start;
		if (ptmp) {
704
			cFYI(1, "closedir free smb buf in srch struct");
L
Linus Torvalds 已提交
705
			pCFileStruct->srch_inf.ntwrk_buf_start = NULL;
S
Steve French 已提交
706
			if (pCFileStruct->srch_inf.smallBuf)
707 708 709
				cifs_small_buf_release(ptmp);
			else
				cifs_buf_release(ptmp);
L
Linus Torvalds 已提交
710 711 712 713 714 715 716 717 718
		}
		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
719 720 721
static int store_file_lock(struct cifsFileInfo *fid, __u64 len,
				__u64 offset, __u8 lockType)
{
S
Steve French 已提交
722 723
	struct cifsLockInfo *li =
		kmalloc(sizeof(struct cifsLockInfo), GFP_KERNEL);
J
[CIFS]  
Jeremy Allison 已提交
724 725 726 727 728
	if (li == NULL)
		return -ENOMEM;
	li->offset = offset;
	li->length = len;
	li->type = lockType;
729
	mutex_lock(&fid->lock_mutex);
J
[CIFS]  
Jeremy Allison 已提交
730
	list_add(&li->llist, &fid->llist);
731
	mutex_unlock(&fid->lock_mutex);
J
[CIFS]  
Jeremy Allison 已提交
732 733 734
	return 0;
}

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

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

752
	cFYI(1, "Lock parm: 0x%x flockflags: "
L
Linus Torvalds 已提交
753
		 "0x%x flocktype: 0x%x start: %lld end: %lld",
S
Steve French 已提交
754
		cmd, pfLock->fl_flags, pfLock->fl_type, pfLock->fl_start,
755
		pfLock->fl_end);
L
Linus Torvalds 已提交
756 757

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

	if (pfLock->fl_type == F_WRLCK) {
775
		cFYI(1, "F_WRLCK ");
L
Linus Torvalds 已提交
776 777
		numLock = 1;
	} else if (pfLock->fl_type == F_UNLCK) {
778
		cFYI(1, "F_UNLCK");
L
Linus Torvalds 已提交
779
		numUnlock = 1;
780 781
		/* Check if unlock includes more than
		one lock range */
L
Linus Torvalds 已提交
782
	} else if (pfLock->fl_type == F_RDLCK) {
783
		cFYI(1, "F_RDLCK");
L
Linus Torvalds 已提交
784 785 786
		lockType |= LOCKING_ANDX_SHARED_LOCK;
		numLock = 1;
	} else if (pfLock->fl_type == F_EXLCK) {
787
		cFYI(1, "F_EXLCK");
L
Linus Torvalds 已提交
788 789
		numLock = 1;
	} else if (pfLock->fl_type == F_SHLCK) {
790
		cFYI(1, "F_SHLCK");
L
Linus Torvalds 已提交
791 792 793
		lockType |= LOCKING_ANDX_SHARED_LOCK;
		numLock = 1;
	} else
794
		cFYI(1, "Unknown type of lock");
L
Linus Torvalds 已提交
795

796
	cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
797
	tcon = cifs_sb->tcon;
L
Linus Torvalds 已提交
798 799

	if (file->private_data == NULL) {
800
		rc = -EBADF;
L
Linus Torvalds 已提交
801
		FreeXid(xid);
802
		return rc;
L
Linus Torvalds 已提交
803
	}
804 805
	netfid = ((struct cifsFileInfo *)file->private_data)->netfid;

806 807
	if ((tcon->ses->capabilities & CAP_UNIX) &&
	    (CIFS_UNIX_FCNTL_CAP & le64_to_cpu(tcon->fsUnixInfo.Capability)) &&
S
Steve French 已提交
808
	    ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOPOSIXBRL) == 0))
809
		posix_locking = 1;
810 811 812
	/* 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
813
	if (IS_GETLK(cmd)) {
S
Steve French 已提交
814
		if (posix_locking) {
815
			int posix_lock_type;
S
Steve French 已提交
816
			if (lockType & LOCKING_ANDX_SHARED_LOCK)
817 818 819
				posix_lock_type = CIFS_RDLCK;
			else
				posix_lock_type = CIFS_WRLCK;
820
			rc = CIFSSMBPosixLock(xid, tcon, netfid, 1 /* get */,
821
					length,	pfLock,
822 823 824 825 826 827
					posix_lock_type, wait_flag);
			FreeXid(xid);
			return rc;
		}

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

		} else {
			/* if rc == ERR_SHARING_VIOLATION ? */
843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859
			rc = 0;

			if (lockType & LOCKING_ANDX_SHARED_LOCK) {
				pfLock->fl_type = F_WRLCK;
			} else {
				rc = CIFSSMBLock(xid, tcon, netfid, length,
					pfLock->fl_start, 0, 1,
					lockType | LOCKING_ANDX_SHARED_LOCK,
					0 /* wait flag */);
				if (rc == 0) {
					rc = CIFSSMBLock(xid, tcon, netfid,
						length, pfLock->fl_start, 1, 0,
						lockType |
						LOCKING_ANDX_SHARED_LOCK,
						0 /* wait flag */);
					pfLock->fl_type = F_RDLCK;
					if (rc != 0)
860
						cERROR(1, "Error unlocking "
861
						"previously locked range %d "
862
						"during test of lock", rc);
863 864 865 866 867 868
					rc = 0;
				} else {
					pfLock->fl_type = F_WRLCK;
					rc = 0;
				}
			}
L
Linus Torvalds 已提交
869 870 871 872 873
		}

		FreeXid(xid);
		return rc;
	}
J
[CIFS]  
Jeremy Allison 已提交
874 875 876 877 878 879 880 881 882

	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) {
883
		int posix_lock_type;
S
Steve French 已提交
884
		if (lockType & LOCKING_ANDX_SHARED_LOCK)
885 886 887
			posix_lock_type = CIFS_RDLCK;
		else
			posix_lock_type = CIFS_WRLCK;
888

S
Steve French 已提交
889
		if (numUnlock == 1)
890
			posix_lock_type = CIFS_UNLCK;
J
[CIFS]  
Jeremy Allison 已提交
891

892
		rc = CIFSSMBPosixLock(xid, tcon, netfid, 0 /* set */,
893
				      length, pfLock,
894
				      posix_lock_type, wait_flag);
J
[CIFS]  
Jeremy Allison 已提交
895
	} else {
S
Steve French 已提交
896 897
		struct cifsFileInfo *fid =
			(struct cifsFileInfo *)file->private_data;
J
[CIFS]  
Jeremy Allison 已提交
898 899

		if (numLock) {
900
			rc = CIFSSMBLock(xid, tcon, netfid, length,
S
Steve French 已提交
901
					pfLock->fl_start,
J
[CIFS]  
Jeremy Allison 已提交
902 903 904 905 906 907 908 909 910 911 912 913 914
					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;

915
			rc = 0;
916
			mutex_lock(&fid->lock_mutex);
J
[CIFS]  
Jeremy Allison 已提交
917 918
			list_for_each_entry_safe(li, tmp, &fid->llist, llist) {
				if (pfLock->fl_start <= li->offset &&
S
Steve French 已提交
919
						(pfLock->fl_start + length) >=
920
						(li->offset + li->length)) {
921
					stored_rc = CIFSSMBLock(xid, tcon,
S
Steve French 已提交
922
							netfid,
J
[CIFS]  
Jeremy Allison 已提交
923
							li->length, li->offset,
924
							1, 0, li->type, false);
J
[CIFS]  
Jeremy Allison 已提交
925 926
					if (stored_rc)
						rc = stored_rc;
927 928 929 930
					else {
						list_del(&li->llist);
						kfree(li);
					}
J
[CIFS]  
Jeremy Allison 已提交
931 932
				}
			}
933
			mutex_unlock(&fid->lock_mutex);
J
[CIFS]  
Jeremy Allison 已提交
934 935 936
		}
	}

937
	if (pfLock->fl_flags & FL_POSIX)
L
Linus Torvalds 已提交
938 939 940 941 942
		posix_lock_file_wait(file, pfLock);
	FreeXid(xid);
	return rc;
}

943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976
/*
 * 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;
}

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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;
987
	struct cifsInodeInfo *cifsi = CIFS_I(file->f_path.dentry->d_inode);
L
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989
	cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
L
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	pTcon = cifs_sb->tcon;

993 994
	/* cFYI(1, " write %d bytes to offset %lld of %s", write_size,
	   *poffset, file->f_path.dentry->d_name.name); */
L
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	if (file->private_data == NULL)
		return -EBADF;
998
	open_file = (struct cifsFileInfo *) file->private_data;
999

1000 1001 1002 1003
	rc = generic_write_checks(file, poffset, &write_size, 0);
	if (rc)
		return rc;

L
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	xid = GetXid();

1006
	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;
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1018
			}
L
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1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030
			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 */
1031
				rc = cifs_reopen_file(file, false);
L
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1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049
				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;
			}
1050 1051
		} else {
			cifs_update_eof(cifsi, *poffset, bytes_written);
L
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			*poffset += bytes_written;
1053
		}
1054
		long_op = CIFS_STD_OP; /* subsequent writes fast -
L
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				    15 seconds is plenty */
	}

1058
	cifs_stats_bytes_written(pTcon, total_written);
L
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1059 1060

	/* since the write may have blocked check these pointers again */
1061 1062
	if ((file->f_path.dentry) && (file->f_path.dentry->d_inode)) {
		struct inode *inode = file->f_path.dentry->d_inode;
S
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/* Do not update local mtime - server will set its actual value on write
 *		inode->i_ctime = inode->i_mtime =
1065 1066 1067 1068 1069
 * 			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
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					*poffset);
1071
			spin_unlock(&inode->i_lock);
L
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1072
		}
S
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		mark_inode_dirty_sync(file->f_path.dentry->d_inode);
L
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1074 1075 1076 1077 1078 1079
	}
	FreeXid(xid);
	return total_written;
}

static ssize_t cifs_write(struct file *file, const char *write_data,
N
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			  size_t write_size, loff_t *poffset)
L
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{
	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;
1089
	struct cifsInodeInfo *cifsi = CIFS_I(file->f_path.dentry->d_inode);
L
Linus Torvalds 已提交
1090

1091
	cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
L
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1092 1093 1094

	pTcon = cifs_sb->tcon;

1095 1096
	cFYI(1, "write %zd bytes to offset %lld of %s", write_size,
	   *poffset, file->f_path.dentry->d_name.name);
L
Linus Torvalds 已提交
1097 1098 1099

	if (file->private_data == NULL)
		return -EBADF;
1100
	open_file = (struct cifsFileInfo *)file->private_data;
1101

L
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	xid = GetXid();

1104
	long_op = cifs_write_timeout(cifsi, *poffset);
L
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1105 1106 1107 1108 1109 1110 1111 1112 1113
	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
1114
			   while we blocked so return what we managed to
L
Linus Torvalds 已提交
1115 1116
			   write */
				return total_written;
S
Steve French 已提交
1117
			}
L
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1118 1119 1120 1121 1122 1123 1124 1125 1126 1127
			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
1128
				   reopen_file not to flush data to
L
Linus Torvalds 已提交
1129
				   server now */
1130
				rc = cifs_reopen_file(file, false);
L
Linus Torvalds 已提交
1131 1132 1133
				if (rc != 0)
					break;
			}
S
Steve French 已提交
1134 1135
			if (experimEnabled || (pTcon->ses->server &&
				((pTcon->ses->server->secMode &
S
Steve French 已提交
1136
				(SECMODE_SIGN_REQUIRED | SECMODE_SIGN_ENABLED))
S
Steve French 已提交
1137
				== 0))) {
1138 1139 1140
				struct kvec iov[2];
				unsigned int len;

1141
				len = min((size_t)cifs_sb->wsize,
1142 1143 1144 1145 1146
					  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;
1147
				rc = CIFSSMBWrite2(xid, pTcon,
1148
						open_file->netfid, len,
1149
						*poffset, &bytes_written,
1150
						iov, 1, long_op);
1151
			} else
1152 1153 1154 1155 1156 1157 1158
				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
1159 1160 1161 1162 1163 1164 1165 1166
		}
		if (rc || (bytes_written == 0)) {
			if (total_written)
				break;
			else {
				FreeXid(xid);
				return rc;
			}
1167 1168
		} else {
			cifs_update_eof(cifsi, *poffset, bytes_written);
L
Linus Torvalds 已提交
1169
			*poffset += bytes_written;
1170
		}
1171
		long_op = CIFS_STD_OP; /* subsequent writes fast -
L
Linus Torvalds 已提交
1172 1173 1174
				    15 seconds is plenty */
	}

1175
	cifs_stats_bytes_written(pTcon, total_written);
L
Linus Torvalds 已提交
1176 1177

	/* since the write may have blocked check these pointers again */
1178
	if ((file->f_path.dentry) && (file->f_path.dentry->d_inode)) {
1179
/*BB We could make this contingent on superblock ATIME flag too */
1180 1181 1182 1183 1184 1185 1186 1187
/*		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
1188
		}
1189
		mark_inode_dirty_sync(file->f_path.dentry->d_inode);
L
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1190 1191 1192 1193 1194
	}
	FreeXid(xid);
	return total_written;
}

S
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1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211
#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 */
1212
				cifsFileInfo_get(open_file);
S
Steve French 已提交
1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225
				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

1226
struct cifsFileInfo *find_writable_file(struct cifsInodeInfo *cifs_inode)
1227 1228
{
	struct cifsFileInfo *open_file;
1229
	bool any_available = false;
1230
	int rc;
1231

1232 1233 1234 1235
	/* 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
1236
	if (cifs_inode == NULL) {
1237
		cERROR(1, "Null inode passed to cifs_writeable_file");
1238 1239 1240 1241
		dump_stack();
		return NULL;
	}

1242
	read_lock(&GlobalSMBSeslock);
1243
refind_writable:
1244
	list_for_each_entry(open_file, &cifs_inode->openFileList, flist) {
1245 1246
		if (open_file->closePend ||
		    (!any_available && open_file->pid != current->tgid))
1247
			continue;
1248

1249 1250 1251
		if (open_file->pfile &&
		    ((open_file->pfile->f_flags & O_RDWR) ||
		     (open_file->pfile->f_flags & O_WRONLY))) {
1252
			cifsFileInfo_get(open_file);
1253 1254 1255 1256 1257 1258

			if (!open_file->invalidHandle) {
				/* found a good writable file */
				read_unlock(&GlobalSMBSeslock);
				return open_file;
			}
S
Steve French 已提交
1259

1260
			read_unlock(&GlobalSMBSeslock);
1261
			/* Had to unlock since following call can block */
1262
			rc = cifs_reopen_file(open_file->pfile, false);
S
Steve French 已提交
1263
			if (!rc) {
1264 1265 1266 1267
				if (!open_file->closePend)
					return open_file;
				else { /* start over in case this was deleted */
				       /* since the list could be modified */
1268
					read_lock(&GlobalSMBSeslock);
1269
					cifsFileInfo_put(open_file);
1270
					goto refind_writable;
1271 1272
				}
			}
1273 1274 1275 1276 1277 1278 1279 1280

			/* 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 */
1281
			cFYI(1, "wp failed on reopen file");
1282 1283 1284
			read_lock(&GlobalSMBSeslock);
			/* can not use this handle, no write
			   pending on this one after all */
1285
			cifsFileInfo_put(open_file);
S
Steve French 已提交
1286

1287 1288 1289 1290 1291 1292 1293 1294 1295
			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. */
1296 1297
		}
	}
1298 1299 1300 1301 1302
	/* couldn't find useable FH with same pid, try any available */
	if (!any_available) {
		any_available = true;
		goto refind_writable;
	}
1303 1304 1305 1306
	read_unlock(&GlobalSMBSeslock);
	return NULL;
}

L
Linus Torvalds 已提交
1307 1308 1309 1310 1311 1312 1313 1314 1315 1316
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;
1317
	struct cifsFileInfo *open_file;
L
Linus Torvalds 已提交
1318 1319 1320 1321 1322 1323 1324 1325 1326 1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 1337 1338 1339 1340 1341 1342

	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
1343
		to = (unsigned)(mapping->host->i_size - offset);
L
Linus Torvalds 已提交
1344

1345 1346 1347 1348
	open_file = find_writable_file(CIFS_I(mapping->host));
	if (open_file) {
		bytes_written = cifs_write(open_file->pfile, write_data,
					   to-from, &offset);
1349
		cifsFileInfo_put(open_file);
L
Linus Torvalds 已提交
1350
		/* Does mm or vfs already set times? */
1351
		inode->i_atime = inode->i_mtime = current_fs_time(inode->i_sb);
1352
		if ((bytes_written > 0) && (offset))
1353
			rc = 0;
1354 1355
		else if (bytes_written < 0)
			rc = bytes_written;
1356
	} else {
1357
		cFYI(1, "No writeable filehandles for inode");
L
Linus Torvalds 已提交
1358 1359 1360 1361 1362 1363 1364 1365
		rc = -EIO;
	}

	kunmap(page);
	return rc;
}

static int cifs_writepages(struct address_space *mapping,
1366
			   struct writeback_control *wbc)
L
Linus Torvalds 已提交
1367
{
1368 1369 1370 1371 1372
	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;
1373
	pgoff_t end;
1374
	pgoff_t index;
S
Steve French 已提交
1375 1376
	int range_whole = 0;
	struct kvec *iov;
1377
	int len;
1378 1379 1380 1381
	int n_iov = 0;
	pgoff_t next;
	int nr_pages;
	__u64 offset = 0;
1382
	struct cifsFileInfo *open_file;
1383
	struct cifsInodeInfo *cifsi = CIFS_I(mapping->host);
1384 1385 1386 1387
	struct page *page;
	struct pagevec pvec;
	int rc = 0;
	int scanned = 0;
1388
	int xid, long_op;
L
Linus Torvalds 已提交
1389

1390
	cifs_sb = CIFS_SB(mapping->host->i_sb);
1391

1392 1393 1394 1395 1396 1397 1398
	/*
	 * 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
1399 1400 1401 1402
	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)
1403
				return generic_writepages(mapping, wbc);
1404

1405
	iov = kmalloc(32 * sizeof(struct kvec), GFP_KERNEL);
S
Steve French 已提交
1406
	if (iov == NULL)
1407 1408 1409
		return generic_writepages(mapping, wbc);


1410 1411 1412 1413 1414 1415
	/*
	 * 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;
1416
		kfree(iov);
1417 1418 1419
		return 0;
	}

L
Linus Torvalds 已提交
1420 1421
	xid = GetXid();

1422
	pagevec_init(&pvec, 0);
1423
	if (wbc->range_cyclic) {
1424
		index = mapping->writeback_index; /* Start from prev offset */
1425 1426 1427 1428 1429 1430
		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;
1431 1432 1433 1434 1435 1436 1437 1438 1439 1440 1441 1442 1443 1444 1445 1446 1447 1448 1449 1450 1451 1452 1453 1454 1455 1456 1457
		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
1458
			else if (!trylock_page(page))
1459 1460 1461 1462 1463 1464 1465
				break;

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

1466
			if (!wbc->range_cyclic && page->index > end) {
1467 1468 1469 1470 1471 1472 1473 1474 1475 1476 1477 1478 1479 1480 1481
				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) ||
1482
					!clear_page_dirty_for_io(page)) {
1483 1484 1485
				unlock_page(page);
				break;
			}
1486

1487 1488 1489 1490 1491 1492
			/*
			 * This actually clears the dirty bit in the radix tree.
			 * See cifs_writepage() for more commentary.
			 */
			set_page_writeback(page);

1493 1494 1495
			if (page_offset(page) >= mapping->host->i_size) {
				done = 1;
				unlock_page(page);
1496
				end_page_writeback(page);
1497 1498 1499
				break;
			}

1500 1501 1502 1503 1504
			/*
			 * BB can we get rid of this?  pages are held by pvec
			 */
			page_cache_get(page);

1505 1506 1507
			len = min(mapping->host->i_size - page_offset(page),
				  (loff_t)PAGE_CACHE_SIZE);

1508 1509 1510
			/* reserve iov[0] for the smb header */
			n_iov++;
			iov[n_iov].iov_base = kmap(page);
1511 1512
			iov[n_iov].iov_len = len;
			bytes_to_write += len;
1513 1514 1515 1516 1517 1518 1519 1520 1521 1522

			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) {
1523 1524 1525 1526 1527 1528
			/* 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) {
1529
				cERROR(1, "No writable handles for inode");
1530
				rc = -EBADF;
S
Steve French 已提交
1531
			} else {
1532
				long_op = cifs_write_timeout(cifsi, offset);
1533 1534 1535 1536
				rc = CIFSSMBWrite2(xid, cifs_sb->tcon,
						   open_file->netfid,
						   bytes_to_write, offset,
						   &bytes_written, iov, n_iov,
1537
						   long_op);
1538
				cifsFileInfo_put(open_file);
1539 1540
				cifs_update_eof(cifsi, offset, bytes_written);

1541
				if (rc || bytes_written < bytes_to_write) {
1542 1543
					cERROR(1, "Write2 ret %d, wrote %d",
						  rc, bytes_written);
1544 1545
					/* BB what if continued retry is
					   requested via mount flags? */
1546 1547 1548 1549
					if (rc == -ENOSPC)
						set_bit(AS_ENOSPC, &mapping->flags);
					else
						set_bit(AS_EIO, &mapping->flags);
1550 1551 1552 1553
				} else {
					cifs_stats_bytes_written(cifs_sb->tcon,
								 bytes_written);
				}
1554 1555 1556
			}
			for (i = 0; i < n_iov; i++) {
				page = pvec.pages[first + i];
1557 1558 1559 1560
				/* 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
1561 1562
				when page marked as error */
				if (rc)
1563
					SetPageError(page);
1564 1565
				kunmap(page);
				unlock_page(page);
1566
				end_page_writeback(page);
1567 1568 1569 1570 1571
				page_cache_release(page);
			}
			if ((wbc->nr_to_write -= n_iov) <= 0)
				done = 1;
			index = next;
1572 1573 1574 1575
		} else
			/* Need to re-find the pages we skipped */
			index = pvec.pages[0]->index + 1;

1576 1577 1578 1579 1580 1581 1582 1583 1584 1585 1586
		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;
	}
1587
	if (wbc->range_cyclic || (range_whole && wbc->nr_to_write > 0))
1588 1589
		mapping->writeback_index = index;

L
Linus Torvalds 已提交
1590
	FreeXid(xid);
1591
	kfree(iov);
L
Linus Torvalds 已提交
1592 1593 1594
	return rc;
}

S
Steve French 已提交
1595
static int cifs_writepage(struct page *page, struct writeback_control *wbc)
L
Linus Torvalds 已提交
1596 1597 1598 1599 1600 1601 1602
{
	int rc = -EFAULT;
	int xid;

	xid = GetXid();
/* BB add check for wbc flags */
	page_cache_get(page);
S
Steve French 已提交
1603
	if (!PageUptodate(page))
1604
		cFYI(1, "ppw - page not up to date");
1605 1606 1607 1608 1609 1610 1611 1612 1613 1614 1615

	/*
	 * 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
1616
	set_page_writeback(page);
L
Linus Torvalds 已提交
1617 1618 1619
	rc = cifs_partialpagewrite(page, 0, PAGE_CACHE_SIZE);
	SetPageUptodate(page); /* BB add check for error and Clearuptodate? */
	unlock_page(page);
1620 1621
	end_page_writeback(page);
	page_cache_release(page);
L
Linus Torvalds 已提交
1622 1623 1624 1625
	FreeXid(xid);
	return rc;
}

N
Nick Piggin 已提交
1626 1627 1628
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
1629
{
N
Nick Piggin 已提交
1630 1631
	int rc;
	struct inode *inode = mapping->host;
L
Linus Torvalds 已提交
1632

1633 1634
	cFYI(1, "write_end for page %p from pos %lld with %d bytes",
		 page, pos, copied);
N
Nick Piggin 已提交
1635

1636 1637 1638 1639 1640
	if (PageChecked(page)) {
		if (copied == len)
			SetPageUptodate(page);
		ClearPageChecked(page);
	} else if (!PageUptodate(page) && copied == PAGE_CACHE_SIZE)
N
Nick Piggin 已提交
1641
		SetPageUptodate(page);
S
Steve French 已提交
1642

L
Linus Torvalds 已提交
1643
	if (!PageUptodate(page)) {
N
Nick Piggin 已提交
1644 1645 1646 1647 1648
		char *page_data;
		unsigned offset = pos & (PAGE_CACHE_SIZE - 1);
		int xid;

		xid = GetXid();
L
Linus Torvalds 已提交
1649 1650 1651 1652 1653 1654
		/* 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
1655 1656
		rc = cifs_write(file, page_data + offset, copied, &pos);
		/* if (rc < 0) should we set writebehind rc? */
L
Linus Torvalds 已提交
1657
		kunmap(page);
N
Nick Piggin 已提交
1658 1659

		FreeXid(xid);
S
Steve French 已提交
1660
	} else {
N
Nick Piggin 已提交
1661 1662
		rc = copied;
		pos += copied;
L
Linus Torvalds 已提交
1663 1664 1665
		set_page_dirty(page);
	}

N
Nick Piggin 已提交
1666 1667 1668 1669 1670 1671 1672 1673 1674 1675
	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
1676 1677 1678
	return rc;
}

1679
int cifs_fsync(struct file *file, int datasync)
L
Linus Torvalds 已提交
1680 1681 1682
{
	int xid;
	int rc = 0;
1683 1684 1685
	struct cifsTconInfo *tcon;
	struct cifsFileInfo *smbfile =
		(struct cifsFileInfo *)file->private_data;
1686
	struct inode *inode = file->f_path.dentry->d_inode;
L
Linus Torvalds 已提交
1687 1688 1689

	xid = GetXid();

1690
	cFYI(1, "Sync file - name: %s datasync: 0x%x",
1691
		file->f_path.dentry->d_name.name, datasync);
1692

1693 1694 1695
	rc = filemap_write_and_wait(inode->i_mapping);
	if (rc == 0) {
		rc = CIFS_I(inode)->write_behind_rc;
L
Linus Torvalds 已提交
1696
		CIFS_I(inode)->write_behind_rc = 0;
1697
		tcon = CIFS_SB(inode->i_sb)->tcon;
1698
		if (!rc && tcon && smbfile &&
S
Steve French 已提交
1699
		   !(CIFS_SB(inode->i_sb)->mnt_cifs_flags & CIFS_MOUNT_NOSSYNC))
1700
			rc = CIFSSMBFlush(xid, tcon, smbfile->netfid);
1701
	}
1702

L
Linus Torvalds 已提交
1703 1704 1705 1706
	FreeXid(xid);
	return rc;
}

1707
/* static void cifs_sync_page(struct page *page)
L
Linus Torvalds 已提交
1708 1709 1710 1711 1712 1713 1714
{
	struct address_space *mapping;
	struct inode *inode;
	unsigned long index = page->index;
	unsigned int rpages = 0;
	int rc = 0;

1715
	cFYI(1, "sync page %p", page);
L
Linus Torvalds 已提交
1716 1717 1718 1719 1720
	mapping = page->mapping;
	if (!mapping)
		return 0;
	inode = mapping->host;
	if (!inode)
1721
		return; */
L
Linus Torvalds 已提交
1722

S
Steve French 已提交
1723
/*	fill in rpages then
L
Linus Torvalds 已提交
1724 1725
	result = cifs_pagein_inode(inode, index, rpages); */ /* BB finish */

1726
/*	cFYI(1, "rpages is %d for sync page of Index %ld", rpages, index);
L
Linus Torvalds 已提交
1727

1728
#if 0
L
Linus Torvalds 已提交
1729 1730 1731
	if (rc < 0)
		return rc;
	return 0;
1732
#endif
L
Linus Torvalds 已提交
1733 1734 1735 1736 1737 1738
} */

/*
 * As file closes, flush all cached write data for this inode checking
 * for write behind errors.
 */
1739
int cifs_flush(struct file *file, fl_owner_t id)
L
Linus Torvalds 已提交
1740
{
S
Steve French 已提交
1741
	struct inode *inode = file->f_path.dentry->d_inode;
L
Linus Torvalds 已提交
1742 1743 1744 1745 1746 1747 1748 1749 1750 1751 1752 1753
	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);
1754 1755 1756
	/* 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
1757
		CIFS_I(inode)->write_behind_rc = 0;
1758
	}
1759

1760
	cFYI(1, "Flush inode %p file %p rc %d", inode, file, rc);
L
Linus Torvalds 已提交
1761 1762 1763 1764 1765 1766 1767 1768 1769 1770 1771 1772 1773 1774 1775 1776 1777 1778 1779 1780

	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();
1781
	cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
L
Linus Torvalds 已提交
1782 1783 1784
	pTcon = cifs_sb->tcon;

	if (file->private_data == NULL) {
1785
		rc = -EBADF;
L
Linus Torvalds 已提交
1786
		FreeXid(xid);
1787
		return rc;
L
Linus Torvalds 已提交
1788 1789 1790
	}
	open_file = (struct cifsFileInfo *)file->private_data;

S
Steve French 已提交
1791
	if ((file->f_flags & O_ACCMODE) == O_WRONLY)
1792
		cFYI(1, "attempting read on write only file instance");
S
Steve French 已提交
1793

L
Linus Torvalds 已提交
1794 1795 1796
	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
1797
		current_read_size = min_t(const int, read_size - total_read,
L
Linus Torvalds 已提交
1798 1799 1800 1801
					  cifs_sb->rsize);
		rc = -EAGAIN;
		smb_read_data = NULL;
		while (rc == -EAGAIN) {
1802
			int buf_type = CIFS_NO_BUFFER;
S
Steve French 已提交
1803
			if ((open_file->invalidHandle) &&
L
Linus Torvalds 已提交
1804
			    (!open_file->closePend)) {
1805
				rc = cifs_reopen_file(file, true);
L
Linus Torvalds 已提交
1806 1807 1808
				if (rc != 0)
					break;
			}
1809
			rc = CIFSSMBRead(xid, pTcon,
1810 1811 1812 1813
					 open_file->netfid,
					 current_read_size, *poffset,
					 &bytes_read, &smb_read_data,
					 &buf_type);
L
Linus Torvalds 已提交
1814 1815
			pSMBr = (struct smb_com_read_rsp *)smb_read_data;
			if (smb_read_data) {
1816 1817 1818 1819
				if (copy_to_user(current_offset,
						smb_read_data +
						4 /* RFC1001 length field */ +
						le16_to_cpu(pSMBr->DataOffset),
S
Steve French 已提交
1820
						bytes_read))
1821 1822
					rc = -EFAULT;

S
Steve French 已提交
1823
				if (buf_type == CIFS_SMALL_BUFFER)
1824
					cifs_small_buf_release(smb_read_data);
S
Steve French 已提交
1825
				else if (buf_type == CIFS_LARGE_BUFFER)
1826
					cifs_buf_release(smb_read_data);
L
Linus Torvalds 已提交
1827 1828 1829 1830 1831 1832 1833 1834 1835 1836 1837
				smb_read_data = NULL;
			}
		}
		if (rc || (bytes_read == 0)) {
			if (total_read) {
				break;
			} else {
				FreeXid(xid);
				return rc;
			}
		} else {
1838
			cifs_stats_bytes_read(pTcon, bytes_read);
L
Linus Torvalds 已提交
1839 1840 1841 1842 1843 1844 1845 1846 1847 1848 1849 1850 1851 1852 1853 1854 1855 1856 1857 1858
			*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;
1859
	int buf_type = CIFS_NO_BUFFER;
L
Linus Torvalds 已提交
1860 1861

	xid = GetXid();
1862
	cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
L
Linus Torvalds 已提交
1863 1864 1865
	pTcon = cifs_sb->tcon;

	if (file->private_data == NULL) {
1866
		rc = -EBADF;
L
Linus Torvalds 已提交
1867
		FreeXid(xid);
1868
		return rc;
L
Linus Torvalds 已提交
1869 1870 1871 1872
	}
	open_file = (struct cifsFileInfo *)file->private_data;

	if ((file->f_flags & O_ACCMODE) == O_WRONLY)
1873
		cFYI(1, "attempting read on write only file instance");
L
Linus Torvalds 已提交
1874

S
Steve French 已提交
1875
	for (total_read = 0, current_offset = read_data;
L
Linus Torvalds 已提交
1876 1877 1878 1879
	     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);
1880 1881
		/* 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
1882
		if ((pTcon->ses) &&
1883 1884 1885 1886
			!(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
1887 1888
		rc = -EAGAIN;
		while (rc == -EAGAIN) {
S
Steve French 已提交
1889
			if ((open_file->invalidHandle) &&
L
Linus Torvalds 已提交
1890
			    (!open_file->closePend)) {
1891
				rc = cifs_reopen_file(file, true);
L
Linus Torvalds 已提交
1892 1893 1894
				if (rc != 0)
					break;
			}
1895
			rc = CIFSSMBRead(xid, pTcon,
1896 1897 1898 1899
					 open_file->netfid,
					 current_read_size, *poffset,
					 &bytes_read, &current_offset,
					 &buf_type);
L
Linus Torvalds 已提交
1900 1901 1902 1903 1904 1905 1906 1907 1908
		}
		if (rc || (bytes_read == 0)) {
			if (total_read) {
				break;
			} else {
				FreeXid(xid);
				return rc;
			}
		} else {
1909
			cifs_stats_bytes_read(pTcon, total_read);
L
Linus Torvalds 已提交
1910 1911 1912 1913 1914 1915 1916 1917 1918 1919 1920 1921
			*poffset += bytes_read;
		}
	}
	FreeXid(xid);
	return total_read;
}

int cifs_file_mmap(struct file *file, struct vm_area_struct *vma)
{
	int rc, xid;

	xid = GetXid();
J
Jeff Layton 已提交
1922
	rc = cifs_revalidate_file(file);
L
Linus Torvalds 已提交
1923
	if (rc) {
1924
		cFYI(1, "Validation prior to mmap failed, error=%d", rc);
L
Linus Torvalds 已提交
1925 1926 1927 1928 1929 1930 1931 1932 1933
		FreeXid(xid);
		return rc;
	}
	rc = generic_file_mmap(file, vma);
	FreeXid(xid);
	return rc;
}


S
Steve French 已提交
1934
static void cifs_copy_cache_pages(struct address_space *mapping,
N
Nick Piggin 已提交
1935
	struct list_head *pages, int bytes_read, char *data)
L
Linus Torvalds 已提交
1936 1937 1938 1939 1940 1941 1942 1943 1944 1945 1946
{
	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);

N
Nick Piggin 已提交
1947
		if (add_to_page_cache_lru(page, mapping, page->index,
L
Linus Torvalds 已提交
1948 1949
				      GFP_KERNEL)) {
			page_cache_release(page);
1950
			cFYI(1, "Add page cache failed");
1951 1952
			data += PAGE_CACHE_SIZE;
			bytes_read -= PAGE_CACHE_SIZE;
L
Linus Torvalds 已提交
1953 1954
			continue;
		}
J
Jeff Layton 已提交
1955
		page_cache_release(page);
L
Linus Torvalds 已提交
1956

S
Steve French 已提交
1957
		target = kmap_atomic(page, KM_USER0);
L
Linus Torvalds 已提交
1958 1959 1960 1961

		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
1962
			memset(target + bytes_read, 0,
L
Linus Torvalds 已提交
1963 1964 1965 1966 1967 1968 1969 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987
			       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);
		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
1988
	unsigned int bytes_read = 0;
S
Steve French 已提交
1989
	unsigned int read_size, i;
L
Linus Torvalds 已提交
1990 1991 1992
	char *smb_read_data = NULL;
	struct smb_com_read_rsp *pSMBr;
	struct cifsFileInfo *open_file;
1993
	int buf_type = CIFS_NO_BUFFER;
L
Linus Torvalds 已提交
1994 1995 1996

	xid = GetXid();
	if (file->private_data == NULL) {
1997
		rc = -EBADF;
L
Linus Torvalds 已提交
1998
		FreeXid(xid);
1999
		return rc;
L
Linus Torvalds 已提交
2000 2001
	}
	open_file = (struct cifsFileInfo *)file->private_data;
2002
	cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
L
Linus Torvalds 已提交
2003
	pTcon = cifs_sb->tcon;
2004

2005
	cFYI(DBG2, "rpages: num pages %d", num_pages);
L
Linus Torvalds 已提交
2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018
	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
2019
		expected_index =
L
Linus Torvalds 已提交
2020
			list_entry(page_list->prev, struct page, lru)->index;
S
Steve French 已提交
2021
		list_for_each_entry_reverse(tmp_page, page_list, lru) {
L
Linus Torvalds 已提交
2022 2023 2024 2025
			if (tmp_page->index == expected_index) {
				contig_pages++;
				expected_index++;
			} else
S
Steve French 已提交
2026
				break;
L
Linus Torvalds 已提交
2027 2028 2029 2030 2031 2032 2033 2034 2035 2036 2037
		}
		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);
2038 2039
		cFYI(DBG2, "rpages: read size 0x%x  contiguous pages %d",
				read_size, contig_pages);
L
Linus Torvalds 已提交
2040 2041
		rc = -EAGAIN;
		while (rc == -EAGAIN) {
S
Steve French 已提交
2042
			if ((open_file->invalidHandle) &&
L
Linus Torvalds 已提交
2043
			    (!open_file->closePend)) {
2044
				rc = cifs_reopen_file(file, true);
L
Linus Torvalds 已提交
2045 2046 2047 2048
				if (rc != 0)
					break;
			}

2049
			rc = CIFSSMBRead(xid, pTcon,
2050 2051 2052 2053
					 open_file->netfid,
					 read_size, offset,
					 &bytes_read, &smb_read_data,
					 &buf_type);
2054
			/* BB more RC checks ? */
S
Steve French 已提交
2055
			if (rc == -EAGAIN) {
L
Linus Torvalds 已提交
2056
				if (smb_read_data) {
S
Steve French 已提交
2057
					if (buf_type == CIFS_SMALL_BUFFER)
2058
						cifs_small_buf_release(smb_read_data);
S
Steve French 已提交
2059
					else if (buf_type == CIFS_LARGE_BUFFER)
2060
						cifs_buf_release(smb_read_data);
L
Linus Torvalds 已提交
2061 2062 2063 2064 2065
					smb_read_data = NULL;
				}
			}
		}
		if ((rc < 0) || (smb_read_data == NULL)) {
2066
			cFYI(1, "Read error in readpages: %d", rc);
L
Linus Torvalds 已提交
2067 2068
			break;
		} else if (bytes_read > 0) {
2069
			task_io_account_read(bytes_read);
L
Linus Torvalds 已提交
2070 2071 2072
			pSMBr = (struct smb_com_read_rsp *)smb_read_data;
			cifs_copy_cache_pages(mapping, page_list, bytes_read,
				smb_read_data + 4 /* RFC1001 hdr */ +
N
Nick Piggin 已提交
2073
				le16_to_cpu(pSMBr->DataOffset));
L
Linus Torvalds 已提交
2074 2075

			i +=  bytes_read >> PAGE_CACHE_SHIFT;
2076
			cifs_stats_bytes_read(pTcon, bytes_read);
S
Steve French 已提交
2077
			if ((bytes_read & PAGE_CACHE_MASK) != bytes_read) {
L
Linus Torvalds 已提交
2078 2079
				i++; /* account for partial page */

S
Steve French 已提交
2080
				/* server copy of file can have smaller size
L
Linus Torvalds 已提交
2081
				   than client */
S
Steve French 已提交
2082 2083
				/* 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
2084 2085
				   we will hit it on next read */

O
OGAWA Hirofumi 已提交
2086
				/* break; */
L
Linus Torvalds 已提交
2087 2088
			}
		} else {
2089
			cFYI(1, "No bytes read (%d) at offset %lld . "
2090
				"Cleaning remaining pages from readahead list",
2091
				bytes_read, offset);
S
Steve French 已提交
2092
			/* BB turn off caching and do new lookup on
L
Linus Torvalds 已提交
2093 2094 2095 2096
			   file size at server? */
			break;
		}
		if (smb_read_data) {
S
Steve French 已提交
2097
			if (buf_type == CIFS_SMALL_BUFFER)
2098
				cifs_small_buf_release(smb_read_data);
S
Steve French 已提交
2099
			else if (buf_type == CIFS_LARGE_BUFFER)
2100
				cifs_buf_release(smb_read_data);
L
Linus Torvalds 已提交
2101 2102 2103 2104 2105 2106 2107
			smb_read_data = NULL;
		}
		bytes_read = 0;
	}

/* need to free smb_read_data buf before exit */
	if (smb_read_data) {
S
Steve French 已提交
2108
		if (buf_type == CIFS_SMALL_BUFFER)
2109
			cifs_small_buf_release(smb_read_data);
S
Steve French 已提交
2110
		else if (buf_type == CIFS_LARGE_BUFFER)
2111
			cifs_buf_release(smb_read_data);
L
Linus Torvalds 已提交
2112
		smb_read_data = NULL;
S
Steve French 已提交
2113
	}
L
Linus Torvalds 已提交
2114 2115 2116 2117 2118 2119 2120 2121 2122 2123 2124 2125 2126 2127

	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
2128

L
Linus Torvalds 已提交
2129
	rc = cifs_read(file, read_data, PAGE_CACHE_SIZE, poffset);
S
Steve French 已提交
2130

L
Linus Torvalds 已提交
2131 2132 2133
	if (rc < 0)
		goto io_error;
	else
2134
		cFYI(1, "Bytes read %d", rc);
S
Steve French 已提交
2135

2136 2137
	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
2138

L
Linus Torvalds 已提交
2139 2140 2141 2142 2143 2144
	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
2145

L
Linus Torvalds 已提交
2146
io_error:
S
Steve French 已提交
2147
	kunmap(page);
L
Linus Torvalds 已提交
2148 2149 2150 2151 2152 2153 2154 2155 2156 2157 2158 2159 2160
	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) {
2161
		rc = -EBADF;
L
Linus Torvalds 已提交
2162
		FreeXid(xid);
2163
		return rc;
L
Linus Torvalds 已提交
2164 2165
	}

2166 2167
	cFYI(1, "readpage %p at offset %d 0x%x\n",
		 page, (int)offset, (int)offset);
L
Linus Torvalds 已提交
2168 2169 2170 2171 2172 2173 2174 2175 2176

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

	unlock_page(page);

	FreeXid(xid);
	return rc;
}

2177 2178 2179 2180 2181 2182 2183 2184 2185 2186 2187 2188 2189 2190 2191 2192 2193 2194 2195
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
2196 2197 2198
/* 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
2199
   refreshing the inode only on increases in the file size
L
Linus Torvalds 已提交
2200 2201
   but this is tricky to do without racing with writebehind
   page caching in the current Linux kernel design */
2202
bool is_size_safe_to_change(struct cifsInodeInfo *cifsInode, __u64 end_of_file)
L
Linus Torvalds 已提交
2203
{
2204
	if (!cifsInode)
2205
		return true;
2206

2207 2208
	if (is_inode_writable(cifsInode)) {
		/* This inode is open for write at least once */
2209 2210 2211
		struct cifs_sb_info *cifs_sb;

		cifs_sb = CIFS_SB(cifsInode->vfs_inode.i_sb);
S
Steve French 已提交
2212
		if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_DIRECT_IO) {
S
Steve French 已提交
2213
			/* since no page cache to corrupt on directio
2214
			we can change size safely */
2215
			return true;
2216 2217
		}

S
Steve French 已提交
2218
		if (i_size_read(&cifsInode->vfs_inode) < end_of_file)
2219
			return true;
2220

2221
		return false;
2222
	} else
2223
		return true;
L
Linus Torvalds 已提交
2224 2225
}

N
Nick Piggin 已提交
2226 2227 2228
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
2229
{
N
Nick Piggin 已提交
2230 2231
	pgoff_t index = pos >> PAGE_CACHE_SHIFT;
	loff_t offset = pos & (PAGE_CACHE_SIZE - 1);
2232 2233 2234 2235
	loff_t page_start = pos & PAGE_MASK;
	loff_t i_size;
	struct page *page;
	int rc = 0;
N
Nick Piggin 已提交
2236

2237
	cFYI(1, "write_begin from %lld len %d", (long long)pos, len);
N
Nick Piggin 已提交
2238

2239
	page = grab_cache_page_write_begin(mapping, index, flags);
2240 2241 2242 2243
	if (!page) {
		rc = -ENOMEM;
		goto out;
	}
2244

2245 2246
	if (PageUptodate(page))
		goto out;
2247

2248 2249 2250 2251 2252 2253 2254
	/*
	 * 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;
2255

2256 2257 2258 2259 2260 2261 2262 2263 2264 2265 2266 2267 2268 2269 2270 2271 2272 2273 2274 2275 2276 2277 2278
	/*
	 * 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
2279

2280 2281 2282 2283 2284 2285 2286
	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);
2287 2288 2289 2290
	} 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
2291
		   this will be written out by write_end so is fine */
L
Linus Torvalds 已提交
2292
	}
2293 2294 2295
out:
	*pagep = page;
	return rc;
L
Linus Torvalds 已提交
2296 2297
}

2298 2299 2300 2301 2302 2303 2304 2305 2306 2307 2308
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)) {
S
Steve French 已提交
2309
		if (cinode->clientCanCacheRead)
2310
			break_lease(inode, O_RDONLY);
S
Steve French 已提交
2311
		else
2312
			break_lease(inode, O_WRONLY);
2313 2314 2315 2316 2317 2318 2319 2320 2321
		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;
2322
		cFYI(1, "Oplock flush inode %p rc %d", inode, rc);
2323 2324 2325 2326 2327 2328 2329 2330 2331 2332 2333
	}

	/*
	 * 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);
2334
		cFYI(1, "Oplock release rc = %d", rc);
2335 2336 2337 2338 2339 2340 2341 2342 2343 2344 2345 2346 2347 2348 2349 2350 2351 2352 2353 2354 2355 2356 2357 2358 2359 2360 2361 2362
	}
}

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,
};

2363
const struct address_space_operations cifs_addr_ops = {
L
Linus Torvalds 已提交
2364 2365 2366
	.readpage = cifs_readpage,
	.readpages = cifs_readpages,
	.writepage = cifs_writepage,
2367
	.writepages = cifs_writepages,
N
Nick Piggin 已提交
2368 2369
	.write_begin = cifs_write_begin,
	.write_end = cifs_write_end,
L
Linus Torvalds 已提交
2370 2371 2372 2373
	.set_page_dirty = __set_page_dirty_nobuffers,
	/* .sync_page = cifs_sync_page, */
	/* .direct_IO = */
};
D
Dave Kleikamp 已提交
2374 2375 2376 2377 2378 2379

/*
 * 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.
 */
2380
const struct address_space_operations cifs_addr_ops_smallbuf = {
D
Dave Kleikamp 已提交
2381 2382 2383
	.readpage = cifs_readpage,
	.writepage = cifs_writepage,
	.writepages = cifs_writepages,
N
Nick Piggin 已提交
2384 2385
	.write_begin = cifs_write_begin,
	.write_end = cifs_write_end,
D
Dave Kleikamp 已提交
2386 2387 2388 2389
	.set_page_dirty = __set_page_dirty_nobuffers,
	/* .sync_page = cifs_sync_page, */
	/* .direct_IO = */
};