[CIFS] work around bug in Samba server handling for posix open

Samba server (version 3.3.1 and earlier, and 3.2.8 and earlier) incorrectly
required the O_CREAT flag on posix open (even when a file was not being
created).  This disables posix open (create is still ok) after the first
attempt returns EINVAL (and logs an error, once, recommending that they
update their server).

Acked-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
This commit is contained in:
Steve French 2009-03-04 19:54:08 +00:00
parent 276a74a483
commit 64cc2c6369
3 changed files with 16 additions and 3 deletions

View file

@ -11,6 +11,8 @@ to better ensure that we wait for server to write all of the data to
server disk (not just write it over the network). Add new mount
parameter to allow user to disable sending the (slow) SMB flush on
fsync if desired (fsync still flushes all cached write data to the server).
Posix file open support added (turned off after one attempt if server
fails to support it properly, as with Samba server versions prior to 3.3.2)
Version 1.56
------------

View file

@ -299,6 +299,7 @@ struct cifsTconInfo {
bool unix_ext:1; /* if false disable Linux extensions to CIFS protocol
for this mount even if server would support */
bool local_lease:1; /* check leases (only) on local system not remote */
bool broken_posix_open; /* e.g. Samba server versions < 3.3.2, 3.2.9 */
bool need_reconnect:1; /* connection reset, tid now invalid */
/* BB add field for back pointer to sb struct(s)? */
};

View file

@ -328,7 +328,8 @@ int cifs_open(struct inode *inode, struct file *file)
else
oplock = 0;
if (tcon->unix_ext && (tcon->ses->capabilities & CAP_UNIX) &&
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);
@ -344,11 +345,20 @@ int cifs_open(struct inode *inode, struct file *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;
/* fallthrough to retry open the old way on operation
not supported or DFS errors */
/* else fallthrough to retry open the old way on network i/o
or DFS errors */
}
desiredAccess = cifs_convert_flags(file->f_flags);