cifs: add routines to build sessions and tcons on the fly
This patch is rather large, but it's a bit difficult to do piecemeal...
For non-multiuser mounts, everything will basically work as it does
today. A call to cifs_sb_tlink will return the "master" tcon link.
Turn the tcon pointer in the cifs_sb into a radix tree that uses the
fsuid of the process as a key. The value is a new "tcon_link" struct
that contains info about a tcon that's under construction.
When a new process needs a tcon, it'll call cifs_sb_tcon. That will
then look up the tcon_link in the radix tree. If it exists and is
valid, it's returned.
If it doesn't exist, then we stuff a new tcon_link into the tree and
mark it as pending and then go and try to build the session/tcon.
If that works, the tcon pointer in the tcon_link is updated and the
pending flag is cleared.
If the construction fails, then we set the tcon pointer to an ERR_PTR
and clear the pending flag.
If the radix tree is searched and the tcon_link is marked pending
then we go to sleep and wait for the pending flag to be cleared.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
diff --git a/fs/cifs/cifs_fs_sb.h b/fs/cifs/cifs_fs_sb.h
index e04e692..5ce57bd 100644
--- a/fs/cifs/cifs_fs_sb.h
+++ b/fs/cifs/cifs_fs_sb.h
@@ -15,6 +15,8 @@
* the GNU Lesser General Public License for more details.
*
*/
+#include <linux/radix-tree.h>
+
#ifndef _CIFS_FS_SB_H
#define _CIFS_FS_SB_H
@@ -40,8 +42,9 @@
#define CIFS_MOUNT_MULTIUSER 0x20000 /* multiuser mount */
struct cifs_sb_info {
- struct cifsTconInfo *ptcon; /* primary mount */
- struct list_head nested_tcon_q;
+ struct radix_tree_root tlink_tree;
+#define CIFS_TLINK_MASTER_TAG 0 /* is "master" (mount) tcon */
+ spinlock_t tlink_tree_lock;
struct nls_table *local_nls;
unsigned int rsize;
unsigned int wsize;