9p: Implement TLOCK
Synopsis
size[4] TLock tag[2] fid[4] flock[n]
size[4] RLock tag[2] status[1]
Description
Tlock is used to acquire/release byte range posix locks on a file
identified by given fid. The reply contains status of the lock request
flock structure:
type[1] - Type of lock: F_RDLCK, F_WRLCK, F_UNLCK
flags[4] - Flags could be either of
P9_LOCK_FLAGS_BLOCK - Blocked lock request, if there is a
conflicting lock exists, wait for that lock to be released.
P9_LOCK_FLAGS_RECLAIM - Reclaim lock request, used when client is
trying to reclaim a lock after a server restrart (due to crash)
start[8] - Starting offset for lock
length[8] - Number of bytes to lock
If length is 0, lock all bytes starting at the location 'start'
through to the end of file
pid[4] - PID of the process that wants to take lock
client_id[4] - Unique client id
status[1] - Status of the lock request, can be
P9_LOCK_SUCCESS(0), P9_LOCK_BLOCKED(1), P9_LOCK_ERROR(2) or
P9_LOCK_GRACE(3)
P9_LOCK_SUCCESS - Request was successful
P9_LOCK_BLOCKED - A conflicting lock is held by another process
P9_LOCK_ERROR - Error while processing the lock request
P9_LOCK_GRACE - Server is in grace period, it can't accept new lock
requests in this period (except locks with
P9_LOCK_FLAGS_RECLAIM flag set)
Signed-off-by: M. Mohan Kumar <mohan@in.ibm.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Venkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
diff --git a/include/net/9p/client.h b/include/net/9p/client.h
index 8744e3a..d7dcb14 100644
--- a/include/net/9p/client.h
+++ b/include/net/9p/client.h
@@ -249,6 +249,7 @@
dev_t rdev, gid_t gid, struct p9_qid *);
int p9_client_mkdir_dotl(struct p9_fid *fid, char *name, int mode,
gid_t gid, struct p9_qid *);
+int p9_client_lock_dotl(struct p9_fid *fid, struct p9_flock *flock, u8 *status);
struct p9_req_t *p9_tag_lookup(struct p9_client *, u16);
void p9_client_cb(struct p9_client *c, struct p9_req_t *req);