summaryrefslogtreecommitdiff
path: root/fs/cifs/file.c
diff options
context:
space:
mode:
Diffstat (limited to 'fs/cifs/file.c')
-rw-r--r--fs/cifs/file.c1675
1 files changed, 1675 insertions, 0 deletions
diff --git a/fs/cifs/file.c b/fs/cifs/file.c
new file mode 100644
index 000000000000..dcab7cf1b53b
--- /dev/null
+++ b/fs/cifs/file.c
@@ -0,0 +1,1675 @@
+/*
+ * fs/cifs/file.c
+ *
+ * vfs operations that deal with files
+ *
+ * Copyright (C) International Business Machines Corp., 2002,2003
+ * Author(s): Steve French (sfrench@us.ibm.com)
+ *
+ * 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/stat.h>
+#include <linux/fcntl.h>
+#include <linux/pagemap.h>
+#include <linux/pagevec.h>
+#include <linux/smp_lock.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;
+ init_MUTEX(&private_data->fh_sem);
+ private_data->pfile = file; /* needed for writepage */
+ private_data->pInode = inode;
+ private_data->invalidHandle = FALSE;
+ private_data->closePend = FALSE;
+
+ 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 0x20197;
+}
+
+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
+ return FILE_OPEN;
+}
+
+/* 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 prepare_write */
+ 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);
+ write_unlock(&file->f_owner.lock);
+ 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(le64_to_cpu(buf->LastWriteTime));
+ if (timespec_equal(&file->f_dentry->d_inode->i_mtime, &temp) &&
+ (file->f_dentry->d_inode->i_size ==
+ (loff_t)le64_to_cpu(buf->EndOfFile))) {
+ cFYI(1, ("inode unchanged on server"));
+ } else {
+ if (file->f_dentry->d_inode->i_mapping) {
+ /* BB no need to lock inode until after invalidate
+ since namei code should already have it locked? */
+ filemap_fdatawrite(file->f_dentry->d_inode->i_mapping);
+ filemap_fdatawait(file->f_dentry->d_inode->i_mapping);
+ }
+ cFYI(1, ("invalidating remote inode since open detected it "
+ "changed"));
+ invalidate_remote_inode(file->f_dentry->d_inode);
+ }
+
+client_can_cache:
+ if (pTcon->ses->capabilities & CAP_UNIX)
+ rc = cifs_get_inode_info_unix(&file->f_dentry->d_inode,
+ full_path, inode->i_sb, xid);
+ else
+ rc = cifs_get_inode_info(&file->f_dentry->d_inode,
+ full_path, buf, inode->i_sb, xid);
+
+ if ((*oplock & 0xF) == OPLOCK_EXCLUSIVE) {
+ pCifsInode->clientCanCacheAll = TRUE;
+ pCifsInode->clientCanCacheRead = TRUE;
+ cFYI(1, ("Exclusive Oplock granted on inode %p",
+ file->f_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 *pTcon;
+ struct cifsFileInfo *pCifsFile;
+ struct cifsInodeInfo *pCifsInode;
+ struct list_head *tmp;
+ char *full_path = NULL;
+ int desiredAccess;
+ int disposition;
+ __u16 netfid;
+ FILE_ALL_INFO *buf = NULL;
+
+ xid = GetXid();
+
+ cifs_sb = CIFS_SB(inode->i_sb);
+ pTcon = cifs_sb->tcon;
+
+ if (file->f_flags & O_CREAT) {
+ /* search inode for this file and fill in file->private_data */
+ pCifsInode = CIFS_I(file->f_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) {
+ rc = 0;
+ FreeXid(xid);
+ return rc;
+ } else {
+ if (file->f_flags & O_EXCL)
+ cERROR(1, ("could not find file instance for "
+ "new file %p ", file));
+ }
+ }
+
+ down(&inode->i_sb->s_vfs_rename_sem);
+ full_path = build_path_from_dentry(file->f_dentry);
+ up(&inode->i_sb->s_vfs_rename_sem);
+ 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));
+ 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);
+
+ if (oplockEnabled)
+ oplock = REQ_OPLOCK;
+ else
+ oplock = FALSE;
+
+ /* 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;
+ }
+ rc = CIFSSMBOpen(xid, pTcon, full_path, disposition, desiredAccess,
+ CREATE_NOT_DIR, &netfid, &oplock, buf,
+ cifs_sb->local_nls);
+ 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(&file->f_owner.lock);
+ write_lock(&GlobalSMBSeslock);
+ list_add(&pCifsFile->tlist, &pTcon->openFileList);
+
+ pCifsInode = CIFS_I(file->f_dentry->d_inode);
+ if (pCifsInode) {
+ rc = cifs_open_inode_helper(inode, file, pCifsInode,
+ pCifsFile, pTcon,
+ &oplock, buf, full_path, xid);
+ } else {
+ write_unlock(&GlobalSMBSeslock);
+ write_unlock(&file->f_owner.lock);
+ }
+
+ if (oplock & CIFS_CREATE_ACTION) {
+ /* time to set mode which we can not set earlier due to
+ problems creating new read-only files */
+ if (cifs_sb->tcon->ses->capabilities & CAP_UNIX) {
+ CIFSSMBUnixSetPerms(xid, pTcon, full_path,
+ inode->i_mode,
+ (__u64)-1, (__u64)-1, 0 /* dev */,
+ cifs_sb->local_nls);
+ } else {
+ /* BB implement via Windows security descriptors eg
+ CIFSSMBWinSetPerms(xid, pTcon, full_path, mode,
+ -1, -1, local_nls);
+ in the meantime could set r/o dos attribute when
+ perms are eg: mode & 0222 == 0 */
+ }
+ }
+
+out:
+ kfree(buf);
+ kfree(full_path);
+ FreeXid(xid);
+ return rc;
+}
+
+/* Try to reaquire 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 inode *inode, struct file *file,
+ int can_flush)
+{
+ int rc = -EACCES;
+ int xid, oplock;
+ struct cifs_sb_info *cifs_sb;
+ struct cifsTconInfo *pTcon;
+ struct cifsFileInfo *pCifsFile;
+ struct cifsInodeInfo *pCifsInode;
+ char *full_path = NULL;
+ int desiredAccess;
+ int disposition = FILE_OPEN;
+ __u16 netfid;
+
+ if (inode == NULL)
+ return -EBADF;
+ if (file->private_data) {
+ pCifsFile = (struct cifsFileInfo *)file->private_data;
+ } else
+ return -EBADF;
+
+ xid = GetXid();
+ down(&pCifsFile->fh_sem);
+ if (pCifsFile->invalidHandle == FALSE) {
+ up(&pCifsFile->fh_sem);
+ FreeXid(xid);
+ return 0;
+ }
+
+ if (file->f_dentry == NULL) {
+ up(&pCifsFile->fh_sem);
+ cFYI(1, ("failed file reopen, no valid name if dentry freed"));
+ FreeXid(xid);
+ return -EBADF;
+ }
+ cifs_sb = CIFS_SB(inode->i_sb);
+ pTcon = 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_dentry);
+ if (full_path == NULL) {
+ up(&pCifsFile->fh_sem);
+ FreeXid(xid);
+ return -ENOMEM;
+ }
+
+ cFYI(1, (" inode = 0x%p file flags are 0x%x for %s",
+ inode, file->f_flags,full_path));
+ desiredAccess = cifs_convert_flags(file->f_flags);
+
+ if (oplockEnabled)
+ oplock = REQ_OPLOCK;
+ else
+ oplock = FALSE;
+
+ /* 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 */
+
+/* buf = kmalloc(sizeof(FILE_ALL_INFO), GFP_KERNEL);
+ if (buf == 0) {
+ up(&pCifsFile->fh_sem);
+ kfree(full_path);
+ FreeXid(xid);
+ return -ENOMEM;
+ } */
+ rc = CIFSSMBOpen(xid, pTcon, full_path, disposition, desiredAccess,
+ CREATE_NOT_DIR, &netfid, &oplock, NULL,
+ cifs_sb->local_nls);
+ if (rc) {
+ up(&pCifsFile->fh_sem);
+ cFYI(1, ("cifs_open returned 0x%x ", rc));
+ cFYI(1, ("oplock: %d ", oplock));
+ } else {
+ pCifsFile->netfid = netfid;
+ pCifsFile->invalidHandle = FALSE;
+ up(&pCifsFile->fh_sem);
+ pCifsInode = CIFS_I(inode);
+ if (pCifsInode) {
+ if (can_flush) {
+ filemap_fdatawrite(inode->i_mapping);
+ filemap_fdatawait(inode->i_mapping);
+ /* temporarily disable caching while we
+ go to server to get inode info */
+ pCifsInode->clientCanCacheAll = FALSE;
+ pCifsInode->clientCanCacheRead = FALSE;
+ if (pTcon->ses->capabilities & CAP_UNIX)
+ 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);
+ } /* 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_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;
+ 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) {
+ pSMBFile->closePend = TRUE;
+ write_lock(&file->f_owner.lock);
+ if (pTcon) {
+ /* no sense reconnecting to close a file that is
+ already closed */
+ if (pTcon->tidStatus != CifsNeedReconnect) {
+ write_unlock(&file->f_owner.lock);
+ rc = CIFSSMBClose(xid, pTcon,
+ pSMBFile->netfid);
+ write_lock(&file->f_owner.lock);
+ }
+ }
+ list_del(&pSMBFile->flist);
+ list_del(&pSMBFile->tlist);
+ write_unlock(&file->f_owner.lock);
+ kfree(pSMBFile->search_resume_name);
+ kfree(file->private_data);
+ file->private_data = NULL;
+ } else
+ rc = -EBADF;
+
+ 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;
+ }
+ 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 with ", inode));
+
+ xid = GetXid();
+
+ if (pCFileStruct) {
+ struct cifsTconInfo *pTcon;
+ struct cifs_sb_info *cifs_sb = CIFS_SB(file->f_dentry->d_sb);
+
+ pTcon = cifs_sb->tcon;
+
+ cFYI(1, ("Freeing private data in close dir"));
+ if (pCFileStruct->srch_inf.endOfSearch == FALSE) {
+ pCFileStruct->invalidHandle = TRUE;
+ 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;
+ }
+ ptmp = pCFileStruct->srch_inf.ntwrk_buf_start;
+ if (ptmp) {
+ /* BB removeme BB */ cFYI(1, ("freeing smb buf in srch struct in closedir"));
+ pCFileStruct->srch_inf.ntwrk_buf_start = NULL;
+ cifs_buf_release(ptmp);
+ }
+ ptmp = pCFileStruct->search_resume_name;
+ if (ptmp) {
+ /* BB removeme BB */ cFYI(1, ("freeing resume name in closedir"));
+ pCFileStruct->search_resume_name = NULL;
+ kfree(ptmp);
+ }
+ kfree(file->private_data);
+ file->private_data = NULL;
+ }
+ /* BB can we lock the filestruct while this is going on? */
+ FreeXid(xid);
+ return rc;
+}
+
+int cifs_lock(struct file *file, int cmd, struct file_lock *pfLock)
+{
+ int rc, xid;
+ __u32 lockType = LOCKING_ANDX_LARGE_FILES;
+ __u32 numLock = 0;
+ __u32 numUnlock = 0;
+ __u64 length;
+ int wait_flag = FALSE;
+ struct cifs_sb_info *cifs_sb;
+ struct cifsTconInfo *pTcon;
+
+ 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;
+ } 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_dentry->d_sb);
+ pTcon = cifs_sb->tcon;
+
+ if (file->private_data == NULL) {
+ FreeXid(xid);
+ return -EBADF;
+ }
+
+ if (IS_GETLK(cmd)) {
+ rc = CIFSSMBLock(xid, pTcon,
+ ((struct cifsFileInfo *)file->
+ private_data)->netfid,
+ length,
+ pfLock->fl_start, 0, 1, lockType,
+ 0 /* wait flag */ );
+ if (rc == 0) {
+ rc = CIFSSMBLock(xid, pTcon,
+ ((struct cifsFileInfo *) file->
+ private_data)->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;
+ }
+
+ rc = CIFSSMBLock(xid, pTcon,
+ ((struct cifsFileInfo *) file->private_data)->
+ netfid, length,
+ pfLock->fl_start, numUnlock, numLock, lockType,
+ wait_flag);
+ if (rc == 0 && (pfLock->fl_flags & FL_POSIX))
+ posix_lock_file_wait(file, pfLock);
+ FreeXid(xid);
+ return rc;
+}
+
+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;
+
+ if (file->f_dentry == NULL)
+ return -EBADF;
+
+ cifs_sb = CIFS_SB(file->f_dentry->d_sb);
+ if (cifs_sb == NULL)
+ return -EBADF;
+
+ pTcon = cifs_sb->tcon;
+
+ /* cFYI(1,
+ (" write %d bytes to offset %lld of %s", write_size,
+ *poffset, file->f_dentry->d_name.name)); */
+
+ if (file->private_data == NULL)
+ return -EBADF;
+ else
+ open_file = (struct cifsFileInfo *) file->private_data;
+
+ xid = GetXid();
+ if (file->f_dentry->d_inode == NULL) {
+ FreeXid(xid);
+ return -EBADF;
+ }
+
+ if (*poffset > file->f_dentry->d_inode->i_size)
+ long_op = 2; /* writes past end of file can take a long time */
+ else
+ long_op = 1;
+
+ 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;
+ }
+ if (open_file->closePend) {
+ FreeXid(xid);
+ if (total_written)
+ return total_written;
+ else
+ return -EBADF;
+ }
+ if (open_file->invalidHandle) {
+ if ((file->f_dentry == NULL) ||
+ (file->f_dentry->d_inode == NULL)) {
+ FreeXid(xid);
+ return total_written;
+ }
+ /* we could deadlock if we called
+ filemap_fdatawait from here so tell
+ reopen_file not to flush data to server
+ now */
+ rc = cifs_reopen_file(file->f_dentry->d_inode,
+ file, FALSE);
+ 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;
+ }
+ } else
+ *poffset += bytes_written;
+ long_op = FALSE; /* subsequent writes fast -
+ 15 seconds is plenty */
+ }
+
+#ifdef CONFIG_CIFS_STATS
+ if (total_written > 0) {
+ atomic_inc(&pTcon->num_writes);
+ spin_lock(&pTcon->stat_lock);
+ pTcon->bytes_written += total_written;
+ spin_unlock(&pTcon->stat_lock);
+ }
+#endif
+
+ /* since the write may have blocked check these pointers again */
+ if (file->f_dentry) {
+ if (file->f_dentry->d_inode) {
+ struct inode *inode = file->f_dentry->d_inode;
+ inode->i_ctime = inode->i_mtime =
+ current_fs_time(inode->i_sb);
+ if (total_written > 0) {
+ if (*poffset > file->f_dentry->d_inode->i_size)
+ i_size_write(file->f_dentry->d_inode,
+ *poffset);
+ }
+ mark_inode_dirty_sync(file->f_dentry->d_inode);
+ }
+ }
+ FreeXid(xid);
+ return total_written;
+}
+
+static ssize_t cifs_write(struct file *file, const char *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;
+
+ if (file->f_dentry == NULL)
+ return -EBADF;
+
+ cifs_sb = CIFS_SB(file->f_dentry->d_sb);
+ if (cifs_sb == NULL)
+ return -EBADF;
+
+ pTcon = cifs_sb->tcon;
+
+ /* cFYI(1,
+ (" write %d bytes to offset %lld of %s", write_size,
+ *poffset, file->f_dentry->d_name.name)); */
+
+ if (file->private_data == NULL)
+ return -EBADF;
+ else
+ open_file = (struct cifsFileInfo *)file->private_data;
+
+ xid = GetXid();
+ if (file->f_dentry->d_inode == NULL) {
+ FreeXid(xid);
+ return -EBADF;
+ }
+
+ if (*poffset > file->f_dentry->d_inode->i_size)
+ long_op = 2; /* writes past end of file can take a long time */
+ else
+ long_op = 1;
+
+ 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;
+ }
+ if (open_file->closePend) {
+ FreeXid(xid);
+ if (total_written)
+ return total_written;
+ else
+ return -EBADF;
+ }
+ if (open_file->invalidHandle) {
+ if ((file->f_dentry == NULL) ||
+ (file->f_dentry->d_inode == NULL)) {
+ FreeXid(xid);
+ return total_written;
+ }
+ /* we could deadlock if we called
+ filemap_fdatawait from here so tell
+ reopen_file not to flush data to
+ server now */
+ rc = cifs_reopen_file(file->f_dentry->d_inode,
+ file, FALSE);
+ 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,
+ write_data + total_written, NULL, long_op);
+ }
+ if (rc || (bytes_written == 0)) {
+ if (total_written)
+ break;
+ else {
+ FreeXid(xid);
+ return rc;
+ }
+ } else
+ *poffset += bytes_written;
+ long_op = FALSE; /* subsequent writes fast -
+ 15 seconds is plenty */
+ }
+
+#ifdef CONFIG_CIFS_STATS
+ if (total_written > 0) {
+ atomic_inc(&pTcon->num_writes);
+ spin_lock(&pTcon->stat_lock);
+ pTcon->bytes_written += total_written;
+ spin_unlock(&pTcon->stat_lock);
+ }
+#endif
+
+ /* since the write may have blocked check these pointers again */
+ if (file->f_dentry) {
+ if (file->f_dentry->d_inode) {
+ file->f_dentry->d_inode->i_ctime =
+ file->f_dentry->d_inode->i_mtime = CURRENT_TIME;
+ if (total_written > 0) {
+ if (*poffset > file->f_dentry->d_inode->i_size)
+ i_size_write(file->f_dentry->d_inode,
+ *poffset);
+ }
+ mark_inode_dirty_sync(file->f_dentry->d_inode);
+ }
+ }
+ FreeXid(xid);
+ return total_written;
+}
+
+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;
+ struct cifsInodeInfo *cifsInode;
+ struct cifsFileInfo *open_file = NULL;
+ struct list_head *tmp;
+ struct list_head *tmp1;
+
+ 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)
+ to = (unsigned)(mapping->host->i_size - offset);
+
+ cifsInode = CIFS_I(mapping->host);
+ read_lock(&GlobalSMBSeslock);
+ /* BB we should start at the end */
+ list_for_each_safe(tmp, tmp1, &cifsInode->openFileList) {
+ open_file = list_entry(tmp, struct cifsFileInfo, flist);
+ if (open_file->closePend)
+ continue;
+ /* We check if file is open for writing first */
+ if ((open_file->pfile) &&
+ ((open_file->pfile->f_flags & O_RDWR) ||
+ (open_file->pfile->f_flags & O_WRONLY))) {
+ read_unlock(&GlobalSMBSeslock);
+ bytes_written = cifs_write(open_file->pfile,
+ write_data, to-from,
+ &offset);
+ read_lock(&GlobalSMBSeslock);
+ /* Does mm or vfs already set times? */
+ inode->i_atime =
+ inode->i_mtime = current_fs_time(inode->i_sb);
+ if ((bytes_written > 0) && (offset)) {
+ rc = 0;
+ } else if (bytes_written < 0) {
+ if (rc == -EBADF) {
+ /* have seen a case in which kernel seemed to
+ have closed/freed a file even with writes
+ active so we might as well see if there are
+ other file structs to try for the same
+ inode before giving up */
+ continue;
+ } else
+ rc = bytes_written;
+ }
+ break; /* now that we found a valid file handle and
+ tried to write to it we are done, no sense
+ continuing to loop looking for another */
+ }
+ if (tmp->next == NULL) {
+ cFYI(1, ("File instance %p removed", tmp));
+ break;
+ }
+ }
+ read_unlock(&GlobalSMBSeslock);
+ if (open_file == NULL) {
+ cFYI(1, ("No writeable filehandles for inode"));
+ rc = -EIO;
+ }
+
+ kunmap(page);
+ return rc;
+}
+
+#if 0
+static int cifs_writepages(struct address_space *mapping,
+ struct writeback_control *wbc)
+{
+ int rc = -EFAULT;
+ int xid;
+
+ xid = GetXid();
+
+ /* Find contiguous pages then iterate through repeating
+ call 16K write then Setpageuptodate or if LARGE_WRITE_X
+ support then send larger writes via kevec so as to eliminate
+ a memcpy */
+ FreeXid(xid);
+ return rc;
+}
+#endif
+
+static int cifs_writepage(struct page* page, struct writeback_control *wbc)
+{
+ int rc = -EFAULT;
+ int xid;
+
+ xid = GetXid();
+/* BB add check for wbc flags */
+ page_cache_get(page);
+ if (!PageUptodate(page)) {
+ cFYI(1, ("ppw - page not up to date"));
+ }
+
+ rc = cifs_partialpagewrite(page, 0, PAGE_CACHE_SIZE);
+ SetPageUptodate(page); /* BB add check for error and Clearuptodate? */
+ unlock_page(page);
+ page_cache_release(page);
+ FreeXid(xid);
+ return rc;
+}
+
+static int cifs_commit_write(struct file *file, struct page *page,
+ unsigned offset, unsigned to)
+{
+ int xid;
+ int rc = 0;
+ struct inode *inode = page->mapping->host;
+ loff_t position = ((loff_t)page->index << PAGE_CACHE_SHIFT) + to;
+ char *page_data;
+
+ xid = GetXid();
+ cFYI(1, ("commit write for page %p up to position %lld for %d",
+ page, position, to));
+ if (position > inode->i_size) {
+ i_size_write(inode, position);
+ /* if (file->private_data == NULL) {
+ rc = -EBADF;
+ } else {
+ open_file = (struct cifsFileInfo *)file->private_data;
+ cifs_sb = CIFS_SB(inode->i_sb);
+ rc = -EAGAIN;
+ while (rc == -EAGAIN) {
+ if ((open_file->invalidHandle) &&
+ (!open_file->closePend)) {
+ rc = cifs_reopen_file(
+ file->f_dentry->d_inode, file);
+ if (rc != 0)
+ break;
+ }
+ if (!open_file->closePend) {
+ rc = CIFSSMBSetFileSize(xid,
+ cifs_sb->tcon, position,
+ open_file->netfid,
+ open_file->pid, FALSE);
+ } else {
+ rc = -EBADF;
+ break;
+ }
+ }
+ cFYI(1, (" SetEOF (commit write) rc = %d", rc));
+ } */
+ }
+ if (!PageUptodate(page)) {
+ position = ((loff_t)page->index << PAGE_CACHE_SHIFT) + offset;
+ /* can not rely on (or let) writepage write this data */
+ if (to < offset) {
+ cFYI(1, ("Illegal offsets, can not copy from %d to %d",
+ offset, to));
+ FreeXid(xid);
+ return rc;
+ }
+ /* 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);
+ rc = cifs_write(file, page_data + offset, to-offset,
+ &position);
+ if (rc > 0)
+ rc = 0;
+ /* else if (rc < 0) should we set writebehind rc? */
+ kunmap(page);
+ } else {
+ set_page_dirty(page);
+ }
+
+ FreeXid(xid);
+ return rc;
+}
+
+int cifs_fsync(struct file *file, struct dentry *dentry, int datasync)
+{
+ int xid;
+ int rc = 0;
+ struct inode *inode = file->f_dentry->d_inode;
+
+ xid = GetXid();
+
+ cFYI(1, ("Sync file - name: %s datasync: 0x%x ",
+ dentry->d_name.name, datasync));
+
+ rc = filemap_fdatawrite(inode->i_mapping);
+ if (rc == 0)
+ CIFS_I(inode)->write_behind_rc = 0;
+ FreeXid(xid);
+ return rc;
+}
+
+/* static int cifs_sync_page(struct page *page)
+{
+ struct address_space *mapping;
+ struct inode *inode;
+ unsigned long index = page->index;
+ unsigned int rpages = 0;
+ int rc = 0;
+
+ cFYI(1, ("sync page %p",page));
+ mapping = page->mapping;
+ if (!mapping)
+ return 0;
+ inode = mapping->host;
+ if (!inode)
+ return 0; */
+
+/* fill in rpages then
+ result = cifs_pagein_inode(inode, index, rpages); */ /* BB finish */
+
+/* cFYI(1, ("rpages is %d for sync page of Index %ld ", rpages, index));
+
+ if (rc < 0)
+ return rc;
+ return 0;
+} */
+
+/*
+ * As file closes, flush all cached write data for this inode checking
+ * for write behind errors.
+ */
+int cifs_flush(struct file *file)
+{
+ struct inode * inode = file->f_dentry->d_inode;
+ 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);
+ if (!rc) /* reset wb rc if we were able to write out dirty pages */
+ CIFS_I(inode)->write_behind_rc = 0;
+
+ cFYI(1, ("Flush inode %p file %p rc %d",inode,file,rc));
+
+ 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();
+ cifs_sb = CIFS_SB(file->f_dentry->d_sb);
+ pTcon = cifs_sb->tcon;
+
+ if (file->private_data == NULL) {
+ FreeXid(xid);
+ return -EBADF;
+ }
+ open_file = (struct cifsFileInfo *)file->private_data;
+
+ if ((file->f_flags & O_ACCMODE) == O_WRONLY) {
+ cFYI(1, ("attempting read on write only file instance"));
+ }
+ for (total_read = 0, current_offset = read_data;
+ 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);
+ rc = -EAGAIN;
+ smb_read_data = NULL;
+ while (rc == -EAGAIN) {
+ if ((open_file->invalidHandle) &&
+ (!open_file->closePend)) {
+ rc = cifs_reopen_file(file->f_dentry->d_inode,
+ file, TRUE);
+ if (rc != 0)
+ break;
+ }
+
+ rc = CIFSSMBRead(xid, pTcon,
+ open_file->netfid,
+ current_read_size, *poffset,
+ &bytes_read, &smb_read_data);
+
+ pSMBr = (struct smb_com_read_rsp *)smb_read_data;
+ if (copy_to_user(current_offset,
+ smb_read_data + 4 /* RFC1001 hdr */
+ + le16_to_cpu(pSMBr->DataOffset),
+ bytes_read)) {
+ rc = -EFAULT;
+ FreeXid(xid);
+ return rc;
+ }
+ if (smb_read_data) {
+ cifs_buf_release(smb_read_data);
+ smb_read_data = NULL;
+ }
+ }
+ if (rc || (bytes_read == 0)) {
+ if (total_read) {
+ break;
+ } else {
+ FreeXid(xid);
+ return rc;
+ }
+ } else {
+#ifdef CONFIG_CIFS_STATS
+ atomic_inc(&pTcon->num_reads);
+ spin_lock(&pTcon->stat_lock);
+ pTcon->bytes_read += total_read;
+ spin_unlock(&pTcon->stat_lock);
+#endif
+ *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;
+
+ xid = GetXid();
+ cifs_sb = CIFS_SB(file->f_dentry->d_sb);
+ pTcon = cifs_sb->tcon;
+
+ if (file->private_data == NULL) {
+ FreeXid(xid);
+ return -EBADF;
+ }
+ open_file = (struct cifsFileInfo *)file->private_data;
+
+ if ((file->f_flags & O_ACCMODE) == O_WRONLY)
+ cFYI(1, ("attempting read on write only file instance"));
+
+ for (total_read = 0, current_offset = read_data;
+ 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);
+ rc = -EAGAIN;
+ while (rc == -EAGAIN) {
+ if ((open_file->invalidHandle) &&
+ (!open_file->closePend)) {
+ rc = cifs_reopen_file(file->f_dentry->d_inode,
+ file, TRUE);
+ if (rc != 0)
+ break;
+ }
+
+ rc = CIFSSMBRead(xid, pTcon,
+ open_file->netfid,
+ current_read_size, *poffset,
+ &bytes_read, &current_offset);
+ }
+ if (rc || (bytes_read == 0)) {
+ if (total_read) {
+ break;
+ } else {
+ FreeXid(xid);
+ return rc;
+ }
+ } else {
+#ifdef CONFIG_CIFS_STATS
+ atomic_inc(&pTcon->num_reads);
+ spin_lock(&pTcon->stat_lock);
+ pTcon->bytes_read += total_read;
+ spin_unlock(&pTcon->stat_lock);
+#endif
+ *poffset += bytes_read;
+ }
+ }
+ FreeXid(xid);
+ return total_read;
+}
+
+int cifs_file_mmap(struct file *file, struct vm_area_struct *vma)
+{
+ struct dentry *dentry = file->f_dentry;
+ int rc, xid;
+
+ xid = GetXid();
+ rc = cifs_revalidate(dentry);
+ if (rc) {
+ cFYI(1, ("Validation prior to mmap failed, error=%d", rc));
+ FreeXid(xid);
+ return rc;
+ }
+ rc = generic_file_mmap(file, vma);
+ FreeXid(xid);
+ return rc;
+}
+
+
+static void cifs_copy_cache_pages(struct address_space *mapping,
+ struct list_head *pages, int bytes_read, char *data,
+ struct pagevec *plru_pvec)
+{
+ struct page *page;
+ char *target;
+
+ while (bytes_read > 0) {
+ if (list_empty(pages))
+ break;
+
+ page = list_entry(pages->prev, struct page, lru);
+ list_del(&page->lru);
+
+ if (add_to_page_cache(page, mapping, page->index,
+ GFP_KERNEL)) {
+ page_cache_release(page);
+ cFYI(1, ("Add page cache failed"));
+ continue;
+ }
+
+ target = kmap_atomic(page,KM_USER0);
+
+ if (PAGE_CACHE_SIZE > bytes_read) {
+ memcpy(target, data, bytes_read);
+ /* zero the tail end of this partial page */
+ memset(target + bytes_read, 0,
+ PAGE_CACHE_SIZE - bytes_read);
+ bytes_read = 0;
+ } else {
+ memcpy(target, data, PAGE_CACHE_SIZE);
+ bytes_read -= PAGE_CACHE_SIZE;
+ }
+ kunmap_atomic(target, KM_USER0);
+
+ flush_dcache_page(page);
+ SetPageUptodate(page);
+ unlock_page(page);
+ if (!pagevec_add(plru_pvec, page))
+ __pagevec_lru_add(plru_pvec);
+ 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;
+ int bytes_read = 0;
+ unsigned int read_size,i;
+ char *smb_read_data = NULL;
+ struct smb_com_read_rsp *pSMBr;
+ struct pagevec lru_pvec;
+ struct cifsFileInfo *open_file;
+
+ xid = GetXid();
+ if (file->private_data == NULL) {
+ FreeXid(xid);
+ return -EBADF;
+ }
+ open_file = (struct cifsFileInfo *)file->private_data;
+ cifs_sb = CIFS_SB(file->f_dentry->d_sb);
+ pTcon = cifs_sb->tcon;
+
+ pagevec_init(&lru_pvec, 0);
+
+ 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;
+ expected_index =
+ list_entry(page_list->prev, struct page, lru)->index;
+ list_for_each_entry_reverse(tmp_page,page_list,lru) {
+ if (tmp_page->index == expected_index) {
+ contig_pages++;
+ expected_index++;
+ } else
+ break;
+ }
+ 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);
+
+ rc = -EAGAIN;
+ while (rc == -EAGAIN) {
+ if ((open_file->invalidHandle) &&
+ (!open_file->closePend)) {
+ rc = cifs_reopen_file(file->f_dentry->d_inode,
+ file, TRUE);
+ if (rc != 0)
+ break;
+ }
+
+ rc = CIFSSMBRead(xid, pTcon,
+ open_file->netfid,
+ read_size, offset,
+ &bytes_read, &smb_read_data);
+ /* BB need to check return code here */
+ if (rc== -EAGAIN) {
+ if (smb_read_data) {
+ cifs_buf_release(smb_read_data);
+ smb_read_data = NULL;
+ }
+ }
+ }
+ if ((rc < 0) || (smb_read_data == NULL)) {
+ cFYI(1, ("Read error in readpages: %d", rc));
+ /* clean up remaing pages off list */
+ while (!list_empty(page_list) && (i < num_pages)) {
+ page = list_entry(page_list->prev, struct page,
+ lru);
+ list_del(&page->lru);
+ page_cache_release(page);
+ }
+ break;
+ } else if (bytes_read > 0) {
+ pSMBr = (struct smb_com_read_rsp *)smb_read_data;
+ cifs_copy_cache_pages(mapping, page_list, bytes_read,
+ smb_read_data + 4 /* RFC1001 hdr */ +
+ le16_to_cpu(pSMBr->DataOffset), &lru_pvec);
+
+ i += bytes_read >> PAGE_CACHE_SHIFT;
+#ifdef CONFIG_CIFS_STATS
+ atomic_inc(&pTcon->num_reads);
+ spin_lock(&pTcon->stat_lock);
+ pTcon->bytes_read += bytes_read;
+ spin_unlock(&pTcon->stat_lock);
+#endif
+ if ((int)(bytes_read & PAGE_CACHE_MASK) != bytes_read) {
+ i++; /* account for partial page */
+
+ /* server copy of file can have smaller size
+ than client */
+ /* BB do we need to verify this common case ?
+ this case is ok - if we are at server EOF
+ we will hit it on next read */
+
+ /* while (!list_empty(page_list) && (i < num_pages)) {
+ page = list_entry(page_list->prev,
+ struct page, list);
+ list_del(&page->list);
+ page_cache_release(page);
+ }
+ break; */
+ }
+ } else {
+ cFYI(1, ("No bytes read (%d) at offset %lld . "
+ "Cleaning remaining pages from readahead list",
+ bytes_read, offset));
+ /* BB turn off caching and do new lookup on
+ file size at server? */
+ while (!list_empty(page_list) && (i < num_pages)) {
+ page = list_entry(page_list->prev, struct page,
+ lru);
+ list_del(&page->lru);
+
+ /* BB removeme - replace with zero of page? */
+ page_cache_release(page);
+ }
+ break;
+ }
+ if (smb_read_data) {
+ cifs_buf_release(smb_read_data);
+ smb_read_data = NULL;
+ }
+ bytes_read = 0;
+ }
+
+ pagevec_lru_add(&lru_pvec);
+
+/* need to free smb_read_data buf before exit */
+ if (smb_read_data) {
+ cifs_buf_release(smb_read_data);
+ smb_read_data = NULL;
+ }
+
+ 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 */
+
+ rc = cifs_read(file, read_data, PAGE_CACHE_SIZE, poffset);
+
+ if (rc < 0)
+ goto io_error;
+ else
+ cFYI(1, ("Bytes read %d ",rc));
+
+ file->f_dentry->d_inode->i_atime =
+ current_fs_time(file->f_dentry->d_inode->i_sb);
+
+ if (PAGE_CACHE_SIZE > rc)
+ memset(read_data + rc, 0, PAGE_CACHE_SIZE - rc);
+
+ flush_dcache_page(page);
+ SetPageUptodate(page);
+ rc = 0;
+
+io_error:
+ kunmap(page);
+ 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) {
+ FreeXid(xid);
+ return -EBADF;
+ }
+
+ cFYI(1, ("readpage %p at offset %d 0x%x\n",
+ page, (int)offset, (int)offset));
+
+ rc = cifs_readpage_worker(file, page, &offset);
+
+ unlock_page(page);
+
+ FreeXid(xid);
+ return rc;
+}
+
+/* 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
+ refreshing the inode only on increases in the file size
+ but this is tricky to do without racing with writebehind
+ page caching in the current Linux kernel design */
+int is_size_safe_to_change(struct cifsInodeInfo *cifsInode)
+{
+ struct list_head *tmp;
+ struct list_head *tmp1;
+ struct cifsFileInfo *open_file = NULL;
+ int rc = TRUE;
+
+ if (cifsInode == NULL)
+ return rc;
+
+ read_lock(&GlobalSMBSeslock);
+ list_for_each_safe(tmp, tmp1, &cifsInode->openFileList) {
+ open_file = list_entry(tmp, struct cifsFileInfo, flist);
+ if (open_file == NULL)
+ break;
+ if (open_file->closePend)
+ continue;
+ /* We check if file is open for writing,
+ BB we could supplement this with a check to see if file size
+ changes have been flushed to server - ie inode metadata dirty */
+ if ((open_file->pfile) &&
+ ((open_file->pfile->f_flags & O_RDWR) ||
+ (open_file->pfile->f_flags & O_WRONLY))) {
+ rc = FALSE;
+ break;
+ }
+ if (tmp->next == NULL) {
+ cFYI(1, ("File instance %p removed", tmp));
+ break;
+ }
+ }
+ read_unlock(&GlobalSMBSeslock);
+ return rc;
+}
+
+
+static int cifs_prepare_write(struct file *file, struct page *page,
+ unsigned from, unsigned to)
+{
+ int rc = 0;
+ loff_t offset = (loff_t)page->index << PAGE_CACHE_SHIFT;
+ cFYI(1, ("prepare write for page %p from %d to %d",page,from,to));
+ if (!PageUptodate(page)) {
+ /* if (to - from != PAGE_CACHE_SIZE) {
+ void *kaddr = kmap_atomic(page, KM_USER0);
+ memset(kaddr, 0, from);
+ memset(kaddr + to, 0, PAGE_CACHE_SIZE - to);
+ flush_dcache_page(page);
+ kunmap_atomic(kaddr, KM_USER0);
+ } */
+ /* If we are writing a full page it will be up to date,
+ no need to read from the server */
+ if ((to == PAGE_CACHE_SIZE) && (from == 0))
+ SetPageUptodate(page);
+
+ /* might as well read a page, it is fast enough */
+ if ((file->f_flags & O_ACCMODE) != O_WRONLY) {
+ rc = cifs_readpage_worker(file, page, &offset);
+ } else {
+ /* should we try using another file handle if there is one -
+ how would we lock it to prevent close of that handle
+ racing with this read?
+ In any case this will be written out by commit_write */
+ }
+ }
+
+ /* BB should we pass any errors back?
+ e.g. if we do not have read access to the file */
+ return 0;
+}
+
+struct address_space_operations cifs_addr_ops = {
+ .readpage = cifs_readpage,
+ .readpages = cifs_readpages,
+ .writepage = cifs_writepage,
+ .prepare_write = cifs_prepare_write,
+ .commit_write = cifs_commit_write,
+ .set_page_dirty = __set_page_dirty_nobuffers,
+ /* .sync_page = cifs_sync_page, */
+ /* .direct_IO = */
+};
generated by cgit (git 2.34.1) at 2024-05-30 00:39:43 +0000