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file.c
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/*
* fs/cifs/file.c
*
* vfs operations that deal with files
*
* Copyright (C) International Business Machines Corp., 2002,2007
* Author(s): Steve French (sfrench@us.ibm.com)
* Jeremy Allison (jra@samba.org)
*
* 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>
#include <linux/backing-dev.h>
#include <linux/stat.h>
#include <linux/fcntl.h>
#include <linux/pagemap.h>
#include <linux/pagevec.h>
#include <linux/writeback.h>
#include <linux/task_io_accounting_ops.h>
#include <linux/delay.h>
#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 struct cifsFileInfo *cifs_init_private(
struct cifsFileInfo *private_data, struct inode *inode,
struct file *file, __u16 netfid)
{
memset(private_data, 0, sizeof(struct cifsFileInfo));
private_data->netfid = netfid;
private_data->pid = current->tgid;
mutex_init(&private_data->fh_mutex);
mutex_init(&private_data->lock_mutex);
INIT_LIST_HEAD(&private_data->llist);
private_data->pfile = file; /* needed for writepage */
private_data->pInode = inode;
private_data->invalidHandle = false;
private_data->closePend = false;
/* we have to track num writers to the inode, since writepages
does not tell us which handle the write is for so there can
be a close (overlapping with write) of the filehandle that
cifs_writepages chose to use */
atomic_set(&private_data->wrtPending, 0);
return private_data;
}
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);
}
return (READ_CONTROL | FILE_WRITE_ATTRIBUTES | FILE_READ_ATTRIBUTES |
FILE_WRITE_EA | FILE_APPEND_DATA | FILE_WRITE_DATA |
FILE_READ_DATA);
}
static inline fmode_t cifs_posix_convert_flags(unsigned int flags)
{
fmode_t posix_flags = 0;
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;
if (flags & O_SYNC)
posix_flags |= (fmode_t)O_SYNC;
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;
}
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;
else if ((flags & O_TRUNC) == O_TRUNC)
return FILE_OVERWRITE;
else
return FILE_OPEN;
}
/* all arguments to this function must be checked for validity in caller */
static inline int cifs_posix_open_inode_helper(struct inode *inode,
struct file *file, struct cifsInodeInfo *pCifsInode,
struct cifsFileInfo *pCifsFile, int oplock, u16 netfid)
{
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;
}
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;
}
/* 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;
/* want handles we can use to read with first
in the list so we do not have to walk the
list to search for one in write_begin */
if ((file->f_flags & O_ACCMODE) == O_WRONLY) {
list_add_tail(&pCifsFile->flist,
&pCifsInode->openFileList);
} else {
list_add(&pCifsFile->flist,
&pCifsInode->openFileList);
}
write_unlock(&GlobalSMBSeslock);
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 */
temp = cifs_NTtimeToUnix(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) {
/* BB no need to lock inode until after invalidate
since namei code should already have it locked? */
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);
}
client_can_cache:
if (pTcon->unix_ext)
rc = cifs_get_inode_info_unix(&file->f_path.dentry->d_inode,
full_path, inode->i_sb, xid);
else
rc = cifs_get_inode_info(&file->f_path.dentry->d_inode,
full_path, buf, inode->i_sb, xid, NULL);
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;
return rc;
}
int cifs_open(struct inode *inode, struct file *file)
{
int rc = -EACCES;
int xid, oplock;
struct cifs_sb_info *cifs_sb;
struct cifsTconInfo *tcon;
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);
tcon = cifs_sb->tcon;
pCifsInode = CIFS_I(file->f_path.dentry->d_inode);
pCifsFile = cifs_fill_filedata(file);
if (pCifsFile) {
FreeXid(xid);
return 0;
}
full_path = build_path_from_dentry(file->f_path.dentry);
if (full_path == NULL) {
FreeXid(xid);
return -ENOMEM;
}
cFYI(1, ("inode = 0x%p file flags are 0x%x for %s",
inode, file->f_flags, full_path));
if (oplockEnabled)
oplock = REQ_OPLOCK;
else
oplock = 0;
if (!tcon->broken_posix_open && 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 */
rc = cifs_posix_open(full_path, &inode, inode->i_sb,
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 */
pCifsFile = cifs_fill_filedata(file);
cifs_posix_open_inode_helper(inode, file, pCifsInode,
pCifsFile, oplock, netfid);
goto out;
} 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;
} else if ((rc != -EIO) && (rc != -EREMOTE) &&
(rc != -EOPNOTSUPP)) /* path not found or net err */
goto out;
/* else fallthrough to retry open the old way on network i/o
or DFS errors */
}
desiredAccess = cifs_convert_flags(file->f_flags);
/*********************************************************************
* open flag mapping table:
*
* POSIX Flag CIFS Disposition
* ---------- ----------------
* 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
* FILE_SUPERSEDE (ie create whether or not file exists although
* 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)
*?
*? O_SYNC is a reasonable match to CIFS writethrough flag
*? 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) */
/* 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
able to simply do a filemap_fdatawrite/filemap_fdatawait first */
buf = kmalloc(sizeof(FILE_ALL_INFO), GFP_KERNEL);
if (!buf) {
rc = -ENOMEM;
goto out;
}
if (cifs_sb->tcon->ses->capabilities & CAP_NT_SMBS)
rc = CIFSSMBOpen(xid, tcon, full_path, disposition,
desiredAccess, CREATE_NOT_DIR, &netfid, &oplock, buf,
cifs_sb->local_nls, cifs_sb->mnt_cifs_flags
& CIFS_MOUNT_MAP_SPECIAL_CHR);
else
rc = -EIO; /* no NT SMB support fall into legacy open below */
if (rc == -EIO) {
/* Old server, try legacy style OpenX */
rc = SMBLegacyOpen(xid, tcon, full_path, disposition,
desiredAccess, CREATE_NOT_DIR, &netfid, &oplock, buf,
cifs_sb->local_nls, cifs_sb->mnt_cifs_flags
& CIFS_MOUNT_MAP_SPECIAL_CHR);
}
if (rc) {
cFYI(1, ("cifs_open returned 0x%x", rc));
goto out;
}
file->private_data =
kmalloc(sizeof(struct cifsFileInfo), GFP_KERNEL);
if (file->private_data == NULL) {
rc = -ENOMEM;
goto out;
}
pCifsFile = cifs_init_private(file->private_data, inode, file, netfid);
write_lock(&GlobalSMBSeslock);
list_add(&pCifsFile->tlist, &tcon->openFileList);
pCifsInode = CIFS_I(file->f_path.dentry->d_inode);
if (pCifsInode) {
rc = cifs_open_inode_helper(inode, file, pCifsInode,
pCifsFile, tcon,
&oplock, buf, full_path, xid);
} else {
write_unlock(&GlobalSMBSeslock);
}
if (oplock & CIFS_CREATE_ACTION) {
/* time to set mode which we can not set earlier due to
problems creating new read-only files */
if (tcon->unix_ext) {
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,
};
CIFSSMBUnixSetInfo(xid, tcon, full_path, &args,
cifs_sb->local_nls,
cifs_sb->mnt_cifs_flags &
CIFS_MOUNT_MAP_SPECIAL_CHR);
}
}
out:
kfree(buf);
kfree(full_path);
FreeXid(xid);
return rc;
}
/* Try to reacquire byte range locks that were released when session */
/* 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;
}
static int cifs_reopen_file(struct file *file, bool can_flush)
{
int rc = -EACCES;
int xid, oplock;
struct cifs_sb_info *cifs_sb;
struct cifsTconInfo *tcon;
struct cifsFileInfo *pCifsFile;
struct cifsInodeInfo *pCifsInode;
struct inode *inode;
char *full_path = NULL;
int desiredAccess;
int disposition = FILE_OPEN;
__u16 netfid;
if (file->private_data)
pCifsFile = (struct cifsFileInfo *)file->private_data;
else
return -EBADF;
xid = GetXid();
mutex_unlock(&pCifsFile->fh_mutex);
if (!pCifsFile->invalidHandle) {
mutex_lock(&pCifsFile->fh_mutex);
FreeXid(xid);
return 0;
}
if (file->f_path.dentry == NULL) {
cERROR(1, ("no valid name if dentry freed"));
dump_stack();
rc = -EBADF;
goto reopen_error_exit;
}
inode = file->f_path.dentry->d_inode;
if (inode == NULL) {
cERROR(1, ("inode not valid"));
dump_stack();
rc = -EBADF;
goto reopen_error_exit;
}
cifs_sb = CIFS_SB(inode->i_sb);
tcon = cifs_sb->tcon;
/* 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 */
full_path = build_path_from_dentry(file->f_path.dentry);
if (full_path == NULL) {
rc = -ENOMEM;
reopen_error_exit:
mutex_lock(&pCifsFile->fh_mutex);
FreeXid(xid);
return rc;
}
cFYI(1, ("inode = 0x%p file flags 0x%x for %s",
inode, file->f_flags, full_path));
if (oplockEnabled)
oplock = REQ_OPLOCK;
else
oplock = 0;
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 */
rc = cifs_posix_open(full_path, NULL, inode->i_sb,
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);
/* Can not refresh inode by passing in file_info buf to be returned
by SMBOpen and then calling get_inode_info with returned buf
since file might have write behind data that needs to be flushed
and server version of file size can be stale. If we knew for sure
that inode was not dirty locally we could do this */
rc = CIFSSMBOpen(xid, tcon, full_path, disposition, desiredAccess,
CREATE_NOT_DIR, &netfid, &oplock, NULL,
cifs_sb->local_nls, cifs_sb->mnt_cifs_flags &
CIFS_MOUNT_MAP_SPECIAL_CHR);
if (rc) {
mutex_lock(&pCifsFile->fh_mutex);
cFYI(1, ("cifs_open returned 0x%x", rc));
cFYI(1, ("oplock: %d", oplock));
} else {
reopen_success:
pCifsFile->netfid = netfid;
pCifsFile->invalidHandle = false;
mutex_lock(&pCifsFile->fh_mutex);
pCifsInode = CIFS_I(inode);
if (pCifsInode) {
if (can_flush) {
rc = filemap_write_and_wait(inode->i_mapping);
if (rc != 0)
CIFS_I(inode)->write_behind_rc = rc;
/* temporarily disable caching while we
go to server to get inode info */
pCifsInode->clientCanCacheAll = false;
pCifsInode->clientCanCacheRead = false;
if (tcon->unix_ext)
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,
xid, NULL);
} /* 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) {
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;
pCifsInode->clientCanCacheAll = false;
} else {
pCifsInode->clientCanCacheRead = false;
pCifsInode->clientCanCacheAll = false;
}
cifs_relock_file(pCifsFile);
}
}
kfree(full_path);
FreeXid(xid);
return rc;
}
int cifs_close(struct inode *inode, struct file *file)
{
int rc = 0;
int xid, timeout;
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) {
struct cifsLockInfo *li, *tmp;
write_lock(&GlobalSMBSeslock);
pSMBFile->closePend = true;
if (pTcon) {
/* no sense reconnecting to close a file that is
already closed */
if (!pTcon->need_reconnect) {
write_unlock(&GlobalSMBSeslock);
timeout = 2;
while ((atomic_read(&pSMBFile->wrtPending) != 0)
&& (timeout <= 2048)) {
/* 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,
but this should give enough time to
clear the socket */
cFYI(DBG2,
("close delay, write pending"));
msleep(timeout);
timeout *= 4;
}
if (atomic_read(&pSMBFile->wrtPending))
cERROR(1, ("close with pending write"));
if (!pTcon->need_reconnect &&
!pSMBFile->invalidHandle)
rc = CIFSSMBClose(xid, pTcon,
pSMBFile->netfid);
} else
write_unlock(&GlobalSMBSeslock);
} else
write_unlock(&GlobalSMBSeslock);
/* Delete any outstanding lock records.
We'll lose them when the file is closed anyway. */
mutex_lock(&pSMBFile->lock_mutex);
list_for_each_entry_safe(li, tmp, &pSMBFile->llist, llist) {
list_del(&li->llist);
kfree(li);
}
mutex_unlock(&pSMBFile->lock_mutex);
write_lock(&GlobalSMBSeslock);
list_del(&pSMBFile->flist);
list_del(&pSMBFile->tlist);
write_unlock(&GlobalSMBSeslock);
timeout = 10;
/* We waited above to give the SMBWrite a chance to issue
on the wire (so we do not get SMBWrite returning EBADF
if writepages is racing with close. Note that writepages
does not specify a file handle, so it is possible for a file
to be opened twice, and the application close the "wrong"
file handle - in these cases we delay long enough to allow
the SMBWrite to get on the wire before the SMB Close.
We allow total wait here over 45 seconds, more than
oplock break time, and more than enough to allow any write
to complete on the server, or to time out on the client */
while ((atomic_read(&pSMBFile->wrtPending) != 0)
&& (timeout <= 50000)) {
cERROR(1, ("writes pending, delay free of handle"));
msleep(timeout);
timeout *= 8;
}
kfree(file->private_data);
file->private_data = NULL;
} else
rc = -EBADF;
read_lock(&GlobalSMBSeslock);
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 */
CIFS_I(inode)->clientCanCacheRead = false;
CIFS_I(inode)->clientCanCacheAll = false;
}
read_unlock(&GlobalSMBSeslock);
if ((rc == 0) && CIFS_I(inode)->write_behind_rc)
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;
cFYI(1, ("Closedir inode = 0x%p", inode));
xid = GetXid();
if (pCFileStruct) {
struct cifsTconInfo *pTcon;
struct cifs_sb_info *cifs_sb =
CIFS_SB(file->f_path.dentry->d_sb);
pTcon = cifs_sb->tcon;
cFYI(1, ("Freeing private data in close dir"));
write_lock(&GlobalSMBSeslock);
if (!pCFileStruct->srch_inf.endOfSearch &&
!pCFileStruct->invalidHandle) {
pCFileStruct->invalidHandle = true;
write_unlock(&GlobalSMBSeslock);
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;
} else
write_unlock(&GlobalSMBSeslock);
ptmp = pCFileStruct->srch_inf.ntwrk_buf_start;
if (ptmp) {
cFYI(1, ("closedir free smb buf in srch struct"));
pCFileStruct->srch_inf.ntwrk_buf_start = NULL;
if (pCFileStruct->srch_inf.smallBuf)
cifs_small_buf_release(ptmp);
else
cifs_buf_release(ptmp);
}
kfree(file->private_data);
file->private_data = NULL;
}
/* BB can we lock the filestruct while this is going on? */
FreeXid(xid);
return rc;
}
static int store_file_lock(struct cifsFileInfo *fid, __u64 len,
__u64 offset, __u8 lockType)
{
struct cifsLockInfo *li =
kmalloc(sizeof(struct cifsLockInfo), GFP_KERNEL);
if (li == NULL)
return -ENOMEM;
li->offset = offset;
li->length = len;
li->type = lockType;
mutex_lock(&fid->lock_mutex);
list_add(&li->llist, &fid->llist);
mutex_unlock(&fid->lock_mutex);
return 0;
}
int cifs_lock(struct file *file, int cmd, struct file_lock *pfLock)
{
int rc, xid;
__u32 numLock = 0;
__u32 numUnlock = 0;
__u64 length;
bool wait_flag = false;
struct cifs_sb_info *cifs_sb;
struct cifsTconInfo *tcon;
__u16 netfid;
__u8 lockType = LOCKING_ANDX_LARGE_FILES;
bool posix_locking = 0;
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",
cmd, pfLock->fl_flags, pfLock->fl_type, pfLock->fl_start,
pfLock->fl_end));
if (pfLock->fl_flags & FL_POSIX)
cFYI(1, ("Posix"));
if (pfLock->fl_flags & FL_FLOCK)
cFYI(1, ("Flock"));
if (pfLock->fl_flags & FL_SLEEP) {
cFYI(1, ("Blocking lock"));
wait_flag = true;
}
if (pfLock->fl_flags & FL_ACCESS)
cFYI(1, ("Process suspended by mandatory locking - "
"not implemented yet"));
if (pfLock->fl_flags & FL_LEASE)
cFYI(1, ("Lease on file - not implemented yet"));
if (pfLock->fl_flags &
(~(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) {
cFYI(1, ("F_UNLCK"));
numUnlock = 1;
/* Check if unlock includes more than
one lock range */
} else if (pfLock->fl_type == F_RDLCK) {
cFYI(1, ("F_RDLCK"));
lockType |= LOCKING_ANDX_SHARED_LOCK;
numLock = 1;
} else if (pfLock->fl_type == F_EXLCK) {
cFYI(1, ("F_EXLCK"));
numLock = 1;
} else if (pfLock->fl_type == F_SHLCK) {
cFYI(1, ("F_SHLCK"));
lockType |= LOCKING_ANDX_SHARED_LOCK;
numLock = 1;
} else
cFYI(1, ("Unknown type of lock"));
cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
tcon = cifs_sb->tcon;
if (file->private_data == NULL) {
FreeXid(xid);
return -EBADF;
}
netfid = ((struct cifsFileInfo *)file->private_data)->netfid;
if ((tcon->ses->capabilities & CAP_UNIX) &&
(CIFS_UNIX_FCNTL_CAP & le64_to_cpu(tcon->fsUnixInfo.Capability)) &&
((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOPOSIXBRL) == 0))
posix_locking = 1;
/* BB add code here to normalize offset and length to
account for negative length which we can not accept over the
wire */
if (IS_GETLK(cmd)) {
if (posix_locking) {
int posix_lock_type;
if (lockType & LOCKING_ANDX_SHARED_LOCK)
posix_lock_type = CIFS_RDLCK;
else
posix_lock_type = CIFS_WRLCK;
rc = CIFSSMBPosixLock(xid, tcon, netfid, 1 /* get */,
length, pfLock,
posix_lock_type, wait_flag);
FreeXid(xid);
return rc;
}
/* BB we could chain these into one lock request BB */
rc = CIFSSMBLock(xid, tcon, netfid, length, pfLock->fl_start,
0, 1, lockType, 0 /* wait flag */ );
if (rc == 0) {
rc = CIFSSMBLock(xid, tcon, netfid, length,
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 "
"range %d during test of lock", rc));
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;
}
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) {
int posix_lock_type;
if (lockType & LOCKING_ANDX_SHARED_LOCK)
posix_lock_type = CIFS_RDLCK;
else
posix_lock_type = CIFS_WRLCK;
if (numUnlock == 1)
posix_lock_type = CIFS_UNLCK;
rc = CIFSSMBPosixLock(xid, tcon, netfid, 0 /* set */,
length, pfLock,
posix_lock_type, wait_flag);
} else {
struct cifsFileInfo *fid =
(struct cifsFileInfo *)file->private_data;
if (numLock) {
rc = CIFSSMBLock(xid, tcon, netfid, length,
pfLock->fl_start,
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;
rc = 0;
mutex_lock(&fid->lock_mutex);
list_for_each_entry_safe(li, tmp, &fid->llist, llist) {
if (pfLock->fl_start <= li->offset &&
(pfLock->fl_start + length) >=
(li->offset + li->length)) {
stored_rc = CIFSSMBLock(xid, tcon,
netfid,
li->length, li->offset,
1, 0, li->type, false);
if (stored_rc)
rc = stored_rc;
list_del(&li->llist);
kfree(li);
}
}
mutex_unlock(&fid->lock_mutex);
}
}
if (pfLock->fl_flags & FL_POSIX)
posix_lock_file_wait(file, pfLock);
FreeXid(xid);
return rc;
}
/*
* 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;
}
ssize_t cifs_user_write(struct file *file, const char __user *write_data,
size_t write_size, loff_t *poffset)