AFS: implement file locking

Implement file locking for AFS.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 154 insertions, 1 deletions

diff --git a/fs/afs/fsclient.c b/fs/afs/fsclient.c
index 5dff1308b6f0..023b95b0d9d7 100644
--- a/fs/afs/fsclient.c
+++ b/fs/afs/fsclient.c
@@ -67,7 +67,7 @@ static void xdr_decode_AFSFetchStatus(const __be32 **_bp,
         EXTRACT(status->group);
         bp++; /* sync counter */
         data_version |= (u64) ntohl(*bp++) << 32;
-        bp++; /* lock count */
+        EXTRACT(status->lock_count);
         size |= (u64) ntohl(*bp++) << 32;
         bp++; /* spare 4 */
         *_bp = bp;
@@ -1748,3 +1748,156 @@ int afs_fs_get_volume_status(struct afs_server *server,
 
         return afs_make_call(&server->addr, call, GFP_NOFS, wait_mode);
 }
+
+/*
+ * deliver reply data to an FS.SetLock, FS.ExtendLock or FS.ReleaseLock
+ */
+static int afs_deliver_fs_xxxx_lock(struct afs_call *call,
+                                    struct sk_buff *skb, bool last)
+{
+        const __be32 *bp;
+
+        _enter("{%u},{%u},%d", call->unmarshall, skb->len, last);
+
+        afs_transfer_reply(call, skb);
+        if (!last)
+                return 0;
+
+        if (call->reply_size != call->reply_max)
+                return -EBADMSG;
+
+        /* unmarshall the reply once we've received all of it */
+        bp = call->buffer;
+        /* xdr_decode_AFSVolSync(&bp, call->replyX); */
+
+        _leave(" = 0 [done]");
+        return 0;
+}
+
+/*
+ * FS.SetLock operation type
+ */
+static const struct afs_call_type afs_RXFSSetLock = {
+        .name           = "FS.SetLock",
+        .deliver        = afs_deliver_fs_xxxx_lock,
+        .abort_to_error = afs_abort_to_error,
+        .destructor     = afs_flat_call_destructor,
+};
+
+/*
+ * FS.ExtendLock operation type
+ */
+static const struct afs_call_type afs_RXFSExtendLock = {
+        .name           = "FS.ExtendLock",
+        .deliver        = afs_deliver_fs_xxxx_lock,
+        .abort_to_error = afs_abort_to_error,
+        .destructor     = afs_flat_call_destructor,
+};
+
+/*
+ * FS.ReleaseLock operation type
+ */
+static const struct afs_call_type afs_RXFSReleaseLock = {
+        .name           = "FS.ReleaseLock",
+        .deliver        = afs_deliver_fs_xxxx_lock,
+        .abort_to_error = afs_abort_to_error,
+        .destructor     = afs_flat_call_destructor,
+};
+
+/*
+ * get a lock on a file
+ */
+int afs_fs_set_lock(struct afs_server *server,
+                    struct key *key,
+                    struct afs_vnode *vnode,
+                    afs_lock_type_t type,
+                    const struct afs_wait_mode *wait_mode)
+{
+        struct afs_call *call;
+        __be32 *bp;
+
+        _enter("");
+
+        call = afs_alloc_flat_call(&afs_RXFSSetLock, 5 * 4, 6 * 4);
+        if (!call)
+                return -ENOMEM;
+
+        call->key = key;
+        call->reply = vnode;
+        call->service_id = FS_SERVICE;
+        call->port = htons(AFS_FS_PORT);
+
+        /* marshall the parameters */
+        bp = call->request;
+        *bp++ = htonl(FSSETLOCK);
+        *bp++ = htonl(vnode->fid.vid);
+        *bp++ = htonl(vnode->fid.vnode);
+        *bp++ = htonl(vnode->fid.unique);
+        *bp++ = htonl(type);
+
+        return afs_make_call(&server->addr, call, GFP_NOFS, wait_mode);
+}
+
+/*
+ * extend a lock on a file
+ */
+int afs_fs_extend_lock(struct afs_server *server,
+                       struct key *key,
+                       struct afs_vnode *vnode,
+                       const struct afs_wait_mode *wait_mode)
+{
+        struct afs_call *call;
+        __be32 *bp;
+
+        _enter("");
+
+        call = afs_alloc_flat_call(&afs_RXFSExtendLock, 4 * 4, 6 * 4);
+        if (!call)
+                return -ENOMEM;
+
+        call->key = key;
+        call->reply = vnode;
+        call->service_id = FS_SERVICE;
+        call->port = htons(AFS_FS_PORT);
+
+        /* marshall the parameters */
+        bp = call->request;
+        *bp++ = htonl(FSEXTENDLOCK);
+        *bp++ = htonl(vnode->fid.vid);
+        *bp++ = htonl(vnode->fid.vnode);
+        *bp++ = htonl(vnode->fid.unique);
+
+        return afs_make_call(&server->addr, call, GFP_NOFS, wait_mode);
+}
+
+/*
+ * release a lock on a file
+ */
+int afs_fs_release_lock(struct afs_server *server,
+                        struct key *key,
+                        struct afs_vnode *vnode,
+                        const struct afs_wait_mode *wait_mode)
+{
+        struct afs_call *call;
+        __be32 *bp;
+
+        _enter("");
+
+        call = afs_alloc_flat_call(&afs_RXFSReleaseLock, 4 * 4, 6 * 4);
+        if (!call)
+                return -ENOMEM;
+
+        call->key = key;
+        call->reply = vnode;
+        call->service_id = FS_SERVICE;
+        call->port = htons(AFS_FS_PORT);
+
+        /* marshall the parameters */
+        bp = call->request;
+        *bp++ = htonl(FSRELEASELOCK);
+        *bp++ = htonl(vnode->fid.vid);
+        *bp++ = htonl(vnode->fid.vnode);
+        *bp++ = htonl(vnode->fid.unique);
+
+        return afs_make_call(&server->addr, call, GFP_NOFS, wait_mode);
+}