[PATCH] knfsd: Allow lockd to drop replies as appropriate
It is possible for the ->fopen callback from lockd into nfsd to find that an
answer cannot be given straight away (an upcall is needed) and so the request
has to be 'dropped', to be retried later. That error status is not currently
propagated back.
So:
Change nlm_fopen to return nlm error codes (rather than a private
protocol) and define a new nlm_drop_reply code.
Cause nlm_drop_reply to cause the rpc request to get rpc_drop_reply
when this error comes back.
Cause svc_process to drop a request which returns a status of
rpc_drop_reply.
[akpm@osdl.org: fix warning storm]
Cc: Marc Eshel <eshel@almaden.ibm.com>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/fs/lockd/svc4proc.c b/fs/lockd/svc4proc.c
index fa370f6..399ad11 100644
--- a/fs/lockd/svc4proc.c
+++ b/fs/lockd/svc4proc.c
@@ -96,7 +96,7 @@
/* Obtain client and file */
if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
- return rpc_success;
+ return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
/* Now check for conflicting locks */
resp->status = nlmsvc_testlock(file, &argp->lock, &resp->lock);
@@ -126,7 +126,7 @@
/* Obtain client and file */
if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
- return rpc_success;
+ return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
#if 0
/* If supplied state doesn't match current state, we assume it's
@@ -169,7 +169,7 @@
/* Obtain client and file */
if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
- return rpc_success;
+ return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
/* Try to cancel request. */
resp->status = nlmsvc_cancel_blocked(file, &argp->lock);
@@ -202,7 +202,7 @@
/* Obtain client and file */
if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
- return rpc_success;
+ return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
/* Now try to remove the lock */
resp->status = nlmsvc_unlock(file, &argp->lock);
@@ -339,7 +339,7 @@
/* Obtain client and file */
if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
- return rpc_success;
+ return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
/* Now try to create the share */
resp->status = nlmsvc_share_file(host, file, argp);
@@ -372,7 +372,7 @@
/* Obtain client and file */
if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
- return rpc_success;
+ return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
/* Now try to lock the file */
resp->status = nlmsvc_unshare_file(host, file, argp);
diff --git a/fs/lockd/svcproc.c b/fs/lockd/svcproc.c
index 75b2c81..6a931f4 100644
--- a/fs/lockd/svcproc.c
+++ b/fs/lockd/svcproc.c
@@ -59,7 +59,7 @@
struct nlm_host *host = NULL;
struct nlm_file *file = NULL;
struct nlm_lock *lock = &argp->lock;
- u32 error;
+ u32 error = 0;
/* nfsd callbacks must have been installed for this procedure */
if (!nlmsvc_ops)
@@ -88,6 +88,8 @@
no_locks:
if (host)
nlm_release_host(host);
+ if (error)
+ return error;
return nlm_lck_denied_nolocks;
}
@@ -122,7 +124,7 @@
/* Obtain client and file */
if ((resp->status = nlmsvc_retrieve_args(rqstp, argp, &host, &file)))
- return rpc_success;
+ return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
/* Now check for conflicting locks */
resp->status = cast_status(nlmsvc_testlock(file, &argp->lock, &resp->lock));
@@ -153,7 +155,7 @@
/* Obtain client and file */
if ((resp->status = nlmsvc_retrieve_args(rqstp, argp, &host, &file)))
- return rpc_success;
+ return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
#if 0
/* If supplied state doesn't match current state, we assume it's
@@ -196,7 +198,7 @@
/* Obtain client and file */
if ((resp->status = nlmsvc_retrieve_args(rqstp, argp, &host, &file)))
- return rpc_success;
+ return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
/* Try to cancel request. */
resp->status = cast_status(nlmsvc_cancel_blocked(file, &argp->lock));
@@ -229,7 +231,7 @@
/* Obtain client and file */
if ((resp->status = nlmsvc_retrieve_args(rqstp, argp, &host, &file)))
- return rpc_success;
+ return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
/* Now try to remove the lock */
resp->status = cast_status(nlmsvc_unlock(file, &argp->lock));
@@ -368,7 +370,7 @@
/* Obtain client and file */
if ((resp->status = nlmsvc_retrieve_args(rqstp, argp, &host, &file)))
- return rpc_success;
+ return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
/* Now try to create the share */
resp->status = cast_status(nlmsvc_share_file(host, file, argp));
@@ -401,7 +403,7 @@
/* Obtain client and file */
if ((resp->status = nlmsvc_retrieve_args(rqstp, argp, &host, &file)))
- return rpc_success;
+ return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
/* Now try to unshare the file */
resp->status = cast_status(nlmsvc_unshare_file(host, file, argp));
diff --git a/fs/lockd/svcsubs.c b/fs/lockd/svcsubs.c
index c5f9113..7dac96e 100644
--- a/fs/lockd/svcsubs.c
+++ b/fs/lockd/svcsubs.c
@@ -135,12 +135,6 @@
out_free:
kfree(file);
-#ifdef CONFIG_LOCKD_V4
- if (nfserr == 1)
- nfserr = nlm4_stale_fh;
- else
-#endif
- nfserr = nlm_lck_denied;
goto out_unlock;
}
diff --git a/fs/nfsd/lockd.c b/fs/nfsd/lockd.c
index 7b889ff..9b9e7e1 100644
--- a/fs/nfsd/lockd.c
+++ b/fs/nfsd/lockd.c
@@ -39,18 +39,20 @@
fh_put(&fh);
rqstp->rq_client = NULL;
exp_readunlock();
- /* nlm and nfsd don't share error codes.
- * we invent: 0 = no error
- * 1 = stale file handle
- * 2 = other error
+ /* We return nlm error codes as nlm doesn't know
+ * about nfsd, but nfsd does know about nlm..
*/
switch (nfserr) {
case nfs_ok:
return 0;
+ case nfserr_dropit:
+ return nlm_drop_reply;
+#ifdef CONFIG_LOCKD_V4
case nfserr_stale:
- return 1;
+ return nlm4_stale_fh;
+#endif
default:
- return 2;
+ return nlm_lck_denied;
}
}
diff --git a/include/linux/lockd/bind.h b/include/linux/lockd/bind.h
index 81e3a18..aa50d89 100644
--- a/include/linux/lockd/bind.h
+++ b/include/linux/lockd/bind.h
@@ -10,6 +10,11 @@
#define LINUX_LOCKD_BIND_H
#include <linux/lockd/nlm.h>
+/* need xdr-encoded error codes too, so... */
+#include <linux/lockd/xdr.h>
+#ifdef CONFIG_LOCKD_V4
+#include <linux/lockd/xdr4.h>
+#endif
/* Dummy declarations */
struct svc_rqst;
diff --git a/include/linux/lockd/xdr.h b/include/linux/lockd/xdr.h
index bb0a0f1..66fdae3 100644
--- a/include/linux/lockd/xdr.h
+++ b/include/linux/lockd/xdr.h
@@ -13,6 +13,8 @@
#include <linux/nfs.h>
#include <linux/sunrpc/xdr.h>
+struct svc_rqst;
+
#define NLM_MAXCOOKIELEN 32
#define NLM_MAXSTRLEN 1024
@@ -22,6 +24,8 @@
#define nlm_lck_blocked __constant_htonl(NLM_LCK_BLOCKED)
#define nlm_lck_denied_grace_period __constant_htonl(NLM_LCK_DENIED_GRACE_PERIOD)
+#define nlm_drop_reply __constant_htonl(30000)
+
/* Lock info passed via NLM */
struct nlm_lock {
char * caller;
diff --git a/include/linux/sunrpc/msg_prot.h b/include/linux/sunrpc/msg_prot.h
index 1e65f2d..606cb21 100644
--- a/include/linux/sunrpc/msg_prot.h
+++ b/include/linux/sunrpc/msg_prot.h
@@ -56,7 +56,9 @@
RPC_PROG_MISMATCH = 2,
RPC_PROC_UNAVAIL = 3,
RPC_GARBAGE_ARGS = 4,
- RPC_SYSTEM_ERR = 5
+ RPC_SYSTEM_ERR = 5,
+ /* internal use only */
+ RPC_DROP_REPLY = 60000,
};
enum rpc_reject_stat {
diff --git a/include/linux/sunrpc/xdr.h b/include/linux/sunrpc/xdr.h
index 953723b..ac69e55 100644
--- a/include/linux/sunrpc/xdr.h
+++ b/include/linux/sunrpc/xdr.h
@@ -74,6 +74,7 @@
#define rpc_proc_unavail __constant_htonl(RPC_PROC_UNAVAIL)
#define rpc_garbage_args __constant_htonl(RPC_GARBAGE_ARGS)
#define rpc_system_err __constant_htonl(RPC_SYSTEM_ERR)
+#define rpc_drop_reply __constant_htonl(RPC_DROP_REPLY)
#define rpc_auth_ok __constant_htonl(RPC_AUTH_OK)
#define rpc_autherr_badcred __constant_htonl(RPC_AUTH_BADCRED)
diff --git a/net/sunrpc/svc.c b/net/sunrpc/svc.c
index 2807fa0..eb44ec9 100644
--- a/net/sunrpc/svc.c
+++ b/net/sunrpc/svc.c
@@ -828,6 +828,11 @@
*statp = procp->pc_func(rqstp, rqstp->rq_argp, rqstp->rq_resp);
/* Encode reply */
+ if (*statp == rpc_drop_reply) {
+ if (procp->pc_release)
+ procp->pc_release(rqstp, NULL, rqstp->rq_resp);
+ goto dropit;
+ }
if (*statp == rpc_success && (xdr = procp->pc_encode)
&& !xdr(rqstp, resv->iov_base+resv->iov_len, rqstp->rq_resp)) {
dprintk("svc: failed to encode reply\n");
