int cifs_close(struct inode *inode, struct file *file)
{
int rc = 0;
- int xid;
+ int xid, timeout;
struct cifs_sb_info *cifs_sb;
struct cifsTconInfo *pTcon;
struct cifsFileInfo *pSMBFile =
/* no sense reconnecting to close a file that is
already closed */
if (pTcon->tidStatus != CifsNeedReconnect) {
- int timeout = 2;
+ timeout = 2;
while ((atomic_read(&pSMBFile->wrtPending) != 0)
- && (timeout < 1000) ) {
+ && (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
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(pSMBFile->search_resume_name);
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
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);
mutex_lock(&fid->lock_mutex);
list_for_each_entry_safe(li, tmp, &fid->llist, llist) {
if (pfLock->fl_start <= li->offset &&
- length >= li->length) {
+ (pfLock->fl_start + length) >=
+ (li->offset + li->length)) {
stored_rc = CIFSSMBLock(xid, pTcon,
netfid,
li->length, li->offset,
return total_written;
}
+#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 */
+ atomic_inc(&open_file->wrtPending);
+ 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
+
struct cifsFileInfo *find_writable_file(struct cifsInodeInfo *cifs_inode)
{
struct cifsFileInfo *open_file;
}
read_lock(&GlobalSMBSeslock);
+refind_writable:
list_for_each_entry(open_file, &cifs_inode->openFileList, flist) {
if (open_file->closePend)
continue;
((open_file->pfile->f_flags & O_RDWR) ||
(open_file->pfile->f_flags & O_WRONLY))) {
atomic_inc(&open_file->wrtPending);
+
+ if (!open_file->invalidHandle) {
+ /* found a good writable file */
+ read_unlock(&GlobalSMBSeslock);
+ return open_file;
+ }
+
read_unlock(&GlobalSMBSeslock);
- if ((open_file->invalidHandle) &&
- (!open_file->closePend) /* BB fixme -since the second clause can not be true remove it BB */) {
- rc = cifs_reopen_file(open_file->pfile, FALSE);
- /* if it fails, try another handle - might be */
- /* dangerous to hold up writepages with retry */
- if (rc) {
- cFYI(1,
- ("failed on reopen file in wp"));
+ /* Had to unlock since following call can block */
+ rc = cifs_reopen_file(open_file->pfile, FALSE);
+ if (!rc) {
+ if (!open_file->closePend)
+ return open_file;
+ else { /* start over in case this was deleted */
+ /* since the list could be modified */
read_lock(&GlobalSMBSeslock);
- /* can not use this handle, no write
- pending on this one after all */
- atomic_dec
- (&open_file->wrtPending);
- continue;
+ atomic_dec(&open_file->wrtPending);
+ goto refind_writable;
}
}
- return open_file;
+
+ /* if it fails, try another handle if possible -
+ (we can not do this if closePending since
+ loop could be modified - in which case we
+ have to start at the beginning of the list
+ again. Note that it would be bad
+ to hold up writepages here (rather than
+ in caller) with continuous retries */
+ cFYI(1, ("wp failed on reopen file"));
+ read_lock(&GlobalSMBSeslock);
+ /* can not use this handle, no write
+ pending on this one after all */
+ atomic_dec(&open_file->wrtPending);
+
+ 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. */
}
}
read_unlock(&GlobalSMBSeslock);
struct page *page;
struct cifs_sb_info *cifs_sb;
struct cifsTconInfo *pTcon;
- int bytes_read = 0;
+ unsigned int bytes_read = 0;
unsigned int read_size, i;
char *smb_read_data = NULL;
struct smb_com_read_rsp *pSMBr;
i += bytes_read >> PAGE_CACHE_SHIFT;
cifs_stats_bytes_read(pTcon, bytes_read);
- if ((int)(bytes_read & PAGE_CACHE_MASK) != bytes_read) {
+ if ((bytes_read & PAGE_CACHE_MASK) != bytes_read) {
i++; /* account for partial page */
/* server copy of file can have smaller size
return rc;
}
+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;
+}
+
/* 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
page caching in the current Linux kernel design */
int is_size_safe_to_change(struct cifsInodeInfo *cifsInode, __u64 end_of_file)
{
- struct cifsFileInfo *open_file = NULL;
-
- if (cifsInode)
- open_file = find_writable_file(cifsInode);
+ if (!cifsInode)
+ return 1;
- if (open_file) {
+ if (is_inode_writable(cifsInode)) {
+ /* This inode is open for write at least once */
struct cifs_sb_info *cifs_sb;
- /* there is not actually a write pending so let
- this handle go free and allow it to
- be closable if needed */
- atomic_dec(&open_file->wrtPending);
-
cifs_sb = CIFS_SB(cifsInode->vfs_inode.i_sb);
if ( cifs_sb->mnt_cifs_flags & CIFS_MOUNT_DIRECT_IO ) {
/* since no page cache to corrupt on directio
git.openpandora.org / pandora-kernel.git / blobdiff