[PATCH] cifs: clean up handling when server doesn't consistently support inode numbers

[PATCH] cifs: clean up handling when server doesn't consistently support inode numbers

[Jeff Layton]

It's possible that a server will return a valid FileID when we query the
FILE_INTERNAL_INFO for the root inode, but then zeroed out inode numbers
when we do a FindFile with an infolevel of
SMB_FIND_FILE_ID_FULL_DIR_INFO.

In this situation turn off querying for server inode numbers, generate a
warning for the user and just generate an inode number using iunique.
Once we generate any inode number with iunique we can no longer use any
server inode numbers or we risk collisions, so ensure that we don't do
that in cifs_get_inode_info either.

Cc: Stable <stable@kernel.org>
Reported-by: Timothy Normand Miller <theosib@gmail.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
---
 fs/cifs/cifsproto.h |    1 +
 fs/cifs/inode.c     |    7 ++-----
 fs/cifs/misc.c      |   14 ++++++++++++++
 fs/cifs/readdir.c   |    7 ++++---
 4 files changed, 21 insertions(+), 8 deletions(-)

diff --git a/fs/cifs/cifsproto.h b/fs/cifs/cifsproto.h
index 6928c24..5646727 100644
--- a/fs/cifs/cifsproto.h
+++ b/fs/cifs/cifsproto.h
@@ -388,4 +388,5 @@ extern int CIFSSMBSetPosixACL(const int xid, struct cifsTconInfo *tcon,
 		const struct nls_table *nls_codepage, int remap_special_chars);
 extern int CIFSGetExtAttr(const int xid, struct cifsTconInfo *tcon,
 			const int netfid, __u64 *pExtAttrBits, __u64 *pMask);
+extern void cifs_autodisable_serverino(struct cifs_sb_info *cifs_sb);
 #endif			/* _CIFSPROTO_H */
diff --git a/fs/cifs/inode.c b/fs/cifs/inode.c
index 5e24925..cababd8 100644
--- a/fs/cifs/inode.c
+++ b/fs/cifs/inode.c
@@ -512,13 +512,10 @@ int cifs_get_inode_info(struct inode **pinode,
 					cifs_sb->local_nls,
 					cifs_sb->mnt_cifs_flags &
 						CIFS_MOUNT_MAP_SPECIAL_CHR);
-			if (rc1) {
+			if (rc1 || !fattr.cf_uniqueid) {
 				cFYI(1, ("GetSrvInodeNum rc %d", rc1));
 				fattr.cf_uniqueid = iunique(sb, ROOT_I);
-				/* disable serverino if call not supported */
-				if (rc1 == -EINVAL)
-					cifs_sb->mnt_cifs_flags &=
-							~CIFS_MOUNT_SERVER_INUM;
+				cifs_autodisable_serverino(cifs_sb);
 			}
 		} else {
 			fattr.cf_uniqueid = iunique(sb, ROOT_I);
diff --git a/fs/cifs/misc.c b/fs/cifs/misc.c
index 0241b25..1e25efc 100644
--- a/fs/cifs/misc.c
+++ b/fs/cifs/misc.c
@@ -715,3 +715,17 @@ cifsConvertToUCS(__le16 *target, const char *source, int maxlen,
 ctoUCS_out:
 	return i;
 }
+
+void
+cifs_autodisable_serverino(struct cifs_sb_info *cifs_sb)
+{
+	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM) {
+		cifs_sb->mnt_cifs_flags &= CIFS_MOUNT_SERVER_INUM;
+		cERROR(1, ("Autodisabling the use of server inode numbers on "
+			   "%s. This server doesn't seem to support them "
+			   "properly. Hardlinks will not be recognized on this "
+			   "mount. Consider mounting with the \"noserverino\" "
+			   "option to silence this message.",
+			   cifs_sb->tcon->treeName));
+	}
+}
diff --git a/fs/cifs/readdir.c b/fs/cifs/readdir.c
index 1f098ca..f84062f 100644
--- a/fs/cifs/readdir.c
+++ b/fs/cifs/readdir.c
@@ -727,11 +727,12 @@ static int cifs_filldir(char *pfindEntry, struct file *file, filldir_t filldir,
 		cifs_dir_info_to_fattr(&fattr, (FILE_DIRECTORY_INFO *)
 					pfindEntry, cifs_sb);
 
-	/* FIXME: make _to_fattr functions fill this out */
-	if (pCifsF->srch_inf.info_level == SMB_FIND_FILE_ID_FULL_DIR_INFO)
+	if (inum && (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM)) {
 		fattr.cf_uniqueid = inum;
-	else
+	} else {
 		fattr.cf_uniqueid = iunique(sb, ROOT_I);
+		cifs_autodisable_serverino(cifs_sb);
+	}
 
 	ino = cifs_uniqueid_to_ino_t(fattr.cf_uniqueid);
 	tmp_dentry = cifs_readdir_lookup(file->f_dentry, &qstring, &fattr);
-- 
1.6.0.6

[PATCH] cifs: don't use CIFSGetSrvInodeNumber in is_path_accessible

[Jeff Layton]

Because it's lighter weight, CIFS tries to use CIFSGetSrvInodeNumber to
verify the accessibility of the root inode and then falls back to doing a
full QPathInfo if that fails with -EOPNOTSUPP. I have at least a report
of a server that returns NT_STATUS_INTERNAL_ERROR rather than something
that translates to EOPNOTSUPP.

Rather than trying to be clever with that call, just have
is_path_accessible do a normal QPathInfo. That call is widely
supported and it shouldn't increase the overhead significantly.

Cc: Stable <stable@kernel.org>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
---
 fs/cifs/connect.c |    8 --------
 1 files changed, 0 insertions(+), 8 deletions(-)

diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index b090980..63ea83f 100644
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -2220,16 +2220,8 @@ is_path_accessible(int xid, struct cifsTconInfo *tcon,
 		   struct cifs_sb_info *cifs_sb, const char *full_path)
 {
 	int rc;
-	__u64 inode_num;
 	FILE_ALL_INFO *pfile_info;
 
-	rc = CIFSGetSrvInodeNumber(xid, tcon, full_path, &inode_num,
-				   cifs_sb->local_nls,
-				   cifs_sb->mnt_cifs_flags &
-						CIFS_MOUNT_MAP_SPECIAL_CHR);
-	if (rc != -EOPNOTSUPP)
-		return rc;
-
 	pfile_info = kmalloc(sizeof(FILE_ALL_INFO), GFP_KERNEL);
 	if (pfile_info == NULL)
 		return -ENOMEM;
-- 
1.6.0.6