[CIFS] clean up error handling in cifs_unlink

Currently, if a standard delete fails and we end up getting -EACCES
we try to clear ATTR_READONLY and try the delete again. If that
then fails with -ETXTBSY then we try a rename_pending_delete. We
aren't handling other errors appropriately though.

Another client could have deleted the file in the meantime and
we get back -ENOENT, for instance. In that case we wouldn't do a
d_drop. Instead of retrying in a separate call, simply goto the
original call and use the error handling from that.

Also, we weren't properly undoing any attribute changes that
were done before returning an error back to the caller.

CC: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>

fs/cifs/inode.c

@@ -837,12 +837,12 @@ int cifs_unlink(struct inode *dir, struct dentry *dentry)
 	int xid;
 	char *full_path = NULL;
 	struct inode *inode = dentry->d_inode;
-	struct cifsInodeInfo *cifsInode;
+	struct cifsInodeInfo *cifsInode = CIFS_I(inode);
 	struct super_block *sb = dir->i_sb;
 	struct cifs_sb_info *cifs_sb = CIFS_SB(sb);
 	struct cifsTconInfo *tcon = cifs_sb->tcon;
-	struct iattr *attrs;
-	__u32 dosattr;
+	struct iattr *attrs = NULL;
+	__u32 dosattr = 0, origattr = 0;
 
 	cFYI(1, ("cifs_unlink, dir=0x%p, dentry=0x%p", dir, dentry));
 
@@ -867,8 +867,10 @@ int cifs_unlink(struct inode *dir, struct dentry *dentry)
 			goto psx_del_no_retry;
 	}
 
+retry_std_delete:
 	rc = CIFSSMBDelFile(xid, tcon, full_path, cifs_sb->local_nls,
 			cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR);
+
 psx_del_no_retry:
 	if (!rc) {
 		if (inode)
@@ -879,8 +881,7 @@ psx_del_no_retry:
 		rc = cifs_rename_pending_delete(full_path, inode, xid);
 		if (rc == 0)
 			drop_nlink(inode);
-	} else if (rc == -EACCES) {
-		/* try only if r/o attribute set in local lookup data? */
+	} else if (rc == -EACCES && dosattr == 0) {
 		attrs = kzalloc(sizeof(*attrs), GFP_KERNEL);
 		if (attrs == NULL) {
 			rc = -ENOMEM;
@@ -888,28 +889,25 @@ psx_del_no_retry:
 		}
 
 		/* try to reset dos attributes */
-		cifsInode = CIFS_I(inode);
-		dosattr = cifsInode->cifsAttrs & ~ATTR_READONLY;
+		origattr = cifsInode->cifsAttrs;
+		if (origattr == 0)
+			origattr |= ATTR_NORMAL;
+		dosattr = origattr & ~ATTR_READONLY;
 		if (dosattr == 0)
 			dosattr |= ATTR_NORMAL;
 		dosattr |= ATTR_HIDDEN;
 
 		rc = cifs_set_file_info(inode, attrs, xid, full_path, dosattr);
-		kfree(attrs);
 		if (rc != 0)
 			goto out_reval;
-		rc = CIFSSMBDelFile(xid, tcon, full_path, cifs_sb->local_nls,
-				    cifs_sb->mnt_cifs_flags &
-					CIFS_MOUNT_MAP_SPECIAL_CHR);
-		if (rc == 0) {
-			if (inode)
-				drop_nlink(inode);
-		} else if (rc == -ETXTBSY) {
-			rc = cifs_rename_pending_delete(full_path, inode, xid);
-			if (rc == 0)
-				drop_nlink(inode);
-		}
+
+		goto retry_std_delete;
 	}
+
+	/* undo the setattr if we errored out and it's needed */
+	if (rc != 0 && dosattr != 0)
+		cifs_set_file_info(inode, attrs, xid, full_path, origattr);
+
 out_reval:
 	if (inode) {
 		cifsInode = CIFS_I(inode);
@@ -919,9 +917,10 @@ out_reval:
 	}
 	dir->i_ctime = dir->i_mtime = current_fs_time(sb);
 	cifsInode = CIFS_I(dir);
-	cifsInode->time = 0;	/* force revalidate of dir as well */
+	CIFS_I(dir)->time = 0;	/* force revalidate of dir as well */
 
 	kfree(full_path);
+	kfree(attrs);
 	FreeXid(xid);
 	return rc;
 }