On 3 Apr 2017, at 5:40, Benjamin Coddington wrote:
On 1 Apr 2017, at 10:05, Jeff Layton wrote:
On Fri, 2017-03-31 at 23:16 -0400, Benjamin Coddington wrote:
NFS would enjoy the ability to modify the behavior of the NLM
client's
unlock RPC task in order to delay the transmission of the unlock
until IO
that was submitted under that lock has completed. This ability can
ensure
that the NLM client will always complete the transmission of an
unlock even
if the waiting caller has been interrupted with fatal signal.
A struct nlmclnt_operations and callback data pointer can be passed
to
nlmclnt_proc(). The struct nlmclnt_operations defines three callback
operations that will be used in a following patch:
nlmclnt_alloc_call - used to call back after a successful allocation
of
a struct nlm_rqst in nlmclnt_proc().
nlmclnt_unlock_prepare - used to call back during NLM unlock's
rpc_call_prepare. The NLM client defers calling rpc_call_start()
until this callback returns false.
nlmclnt_release_call - used to call back when the NLM client's
struct
nlm_rqst is freed.
Signed-off-by: Benjamin Coddington <bcodding@xxxxxxxxxx>
---
fs/lockd/clntproc.c | 26 +++++++++++++++++++++++++-
fs/nfs/nfs3proc.c | 2 +-
fs/nfs/proc.c | 2 +-
include/linux/lockd/bind.h | 11 +++++++++--
include/linux/lockd/lockd.h | 2 ++
5 files changed, 38 insertions(+), 5 deletions(-)
diff --git a/fs/lockd/clntproc.c b/fs/lockd/clntproc.c
index 112952037933..d2744f4960ed 100644
--- a/fs/lockd/clntproc.c
+++ b/fs/lockd/clntproc.c
@@ -150,9 +150,12 @@ static void nlmclnt_release_lockargs(struct
nlm_rqst *req)
* @host: address of a valid nlm_host context representing the NLM
server
* @cmd: fcntl-style file lock operation to perform
* @fl: address of arguments for the lock operation
+ * @nlmclnt_ops: operations to call back out of nlm
+ * @data: address of data to be sent along with callback
*
*/
-int nlmclnt_proc(struct nlm_host *host, int cmd, struct file_lock
*fl)
+int nlmclnt_proc(struct nlm_host *host, int cmd, struct file_lock
*fl,
+ const struct nlmclnt_operations *nlmclnt_ops, void *data)
Might it be cleaner to put the nlmclnt_operations into the nlm_host?
Could pass a pointer to it in the nlmclnt_initdata when creating the
nfs_server.
Maybe, if 5 args here is too much. But passing nlmclnt_operations
into
nlm_init in nfs_start_lockd() would mean the function pointers in
nlmclnt_operations would need to be exposed in client.c. While this
has
more args, I think it is a bit neater from the NFS side.
Jeff, I looked at this again this morning, and I can't find a cleaner
way to
do this by putting the ops on the host. It will mean plumbing the ops
into
nfs_start_lockd. The other reason is that the ops are specific to the
proc
being passed in, so for LOCK we might use different operations. I'm
open to
suggestions, but I am going to send another version without this change.
Ben
