kernel_optimize_test/fs/lockd/svc4proc.c
NeilBrown d343fce148 [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>
2006-10-17 08:18:46 -07:00

524 lines
14 KiB
C

/*
* linux/fs/lockd/svc4proc.c
*
* Lockd server procedures. We don't implement the NLM_*_RES
* procedures because we don't use the async procedures.
*
* Copyright (C) 1996, Olaf Kirch <okir@monad.swb.de>
*/
#include <linux/types.h>
#include <linux/time.h>
#include <linux/slab.h>
#include <linux/in.h>
#include <linux/sunrpc/svc.h>
#include <linux/sunrpc/clnt.h>
#include <linux/nfsd/nfsd.h>
#include <linux/lockd/lockd.h>
#include <linux/lockd/share.h>
#include <linux/lockd/sm_inter.h>
#define NLMDBG_FACILITY NLMDBG_CLIENT
/*
* Obtain client and file from arguments
*/
static u32
nlm4svc_retrieve_args(struct svc_rqst *rqstp, struct nlm_args *argp,
struct nlm_host **hostp, struct nlm_file **filp)
{
struct nlm_host *host = NULL;
struct nlm_file *file = NULL;
struct nlm_lock *lock = &argp->lock;
u32 error = 0;
/* nfsd callbacks must have been installed for this procedure */
if (!nlmsvc_ops)
return nlm_lck_denied_nolocks;
/* Obtain host handle */
if (!(host = nlmsvc_lookup_host(rqstp, lock->caller, lock->len))
|| (argp->monitor && nsm_monitor(host) < 0))
goto no_locks;
*hostp = host;
/* Obtain file pointer. Not used by FREE_ALL call. */
if (filp != NULL) {
if ((error = nlm_lookup_file(rqstp, &file, &lock->fh)) != 0)
goto no_locks;
*filp = file;
/* Set up the missing parts of the file_lock structure */
lock->fl.fl_file = file->f_file;
lock->fl.fl_owner = (fl_owner_t) host;
lock->fl.fl_lmops = &nlmsvc_lock_operations;
}
return 0;
no_locks:
if (host)
nlm_release_host(host);
if (error)
return error;
return nlm_lck_denied_nolocks;
}
/*
* NULL: Test for presence of service
*/
static int
nlm4svc_proc_null(struct svc_rqst *rqstp, void *argp, void *resp)
{
dprintk("lockd: NULL called\n");
return rpc_success;
}
/*
* TEST: Check for conflicting lock
*/
static int
nlm4svc_proc_test(struct svc_rqst *rqstp, struct nlm_args *argp,
struct nlm_res *resp)
{
struct nlm_host *host;
struct nlm_file *file;
dprintk("lockd: TEST4 called\n");
resp->cookie = argp->cookie;
/* Don't accept test requests during grace period */
if (nlmsvc_grace_period) {
resp->status = nlm_lck_denied_grace_period;
return rpc_success;
}
/* Obtain client and file */
if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
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);
dprintk("lockd: TEST4 status %d\n", ntohl(resp->status));
nlm_release_host(host);
nlm_release_file(file);
return rpc_success;
}
static int
nlm4svc_proc_lock(struct svc_rqst *rqstp, struct nlm_args *argp,
struct nlm_res *resp)
{
struct nlm_host *host;
struct nlm_file *file;
dprintk("lockd: LOCK called\n");
resp->cookie = argp->cookie;
/* Don't accept new lock requests during grace period */
if (nlmsvc_grace_period && !argp->reclaim) {
resp->status = nlm_lck_denied_grace_period;
return rpc_success;
}
/* Obtain client and file */
if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
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
* an old request that time-warped somehow. Any error return would
* do in this case because it's irrelevant anyway.
*
* NB: We don't retrieve the remote host's state yet.
*/
if (host->h_nsmstate && host->h_nsmstate != argp->state) {
resp->status = nlm_lck_denied_nolocks;
} else
#endif
/* Now try to lock the file */
resp->status = nlmsvc_lock(rqstp, file, &argp->lock,
argp->block, &argp->cookie);
dprintk("lockd: LOCK status %d\n", ntohl(resp->status));
nlm_release_host(host);
nlm_release_file(file);
return rpc_success;
}
static int
nlm4svc_proc_cancel(struct svc_rqst *rqstp, struct nlm_args *argp,
struct nlm_res *resp)
{
struct nlm_host *host;
struct nlm_file *file;
dprintk("lockd: CANCEL called\n");
resp->cookie = argp->cookie;
/* Don't accept requests during grace period */
if (nlmsvc_grace_period) {
resp->status = nlm_lck_denied_grace_period;
return rpc_success;
}
/* Obtain client and file */
if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
/* Try to cancel request. */
resp->status = nlmsvc_cancel_blocked(file, &argp->lock);
dprintk("lockd: CANCEL status %d\n", ntohl(resp->status));
nlm_release_host(host);
nlm_release_file(file);
return rpc_success;
}
/*
* UNLOCK: release a lock
*/
static int
nlm4svc_proc_unlock(struct svc_rqst *rqstp, struct nlm_args *argp,
struct nlm_res *resp)
{
struct nlm_host *host;
struct nlm_file *file;
dprintk("lockd: UNLOCK called\n");
resp->cookie = argp->cookie;
/* Don't accept new lock requests during grace period */
if (nlmsvc_grace_period) {
resp->status = nlm_lck_denied_grace_period;
return rpc_success;
}
/* Obtain client and file */
if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
/* Now try to remove the lock */
resp->status = nlmsvc_unlock(file, &argp->lock);
dprintk("lockd: UNLOCK status %d\n", ntohl(resp->status));
nlm_release_host(host);
nlm_release_file(file);
return rpc_success;
}
/*
* GRANTED: A server calls us to tell that a process' lock request
* was granted
*/
static int
nlm4svc_proc_granted(struct svc_rqst *rqstp, struct nlm_args *argp,
struct nlm_res *resp)
{
resp->cookie = argp->cookie;
dprintk("lockd: GRANTED called\n");
resp->status = nlmclnt_grant(&rqstp->rq_addr, &argp->lock);
dprintk("lockd: GRANTED status %d\n", ntohl(resp->status));
return rpc_success;
}
/*
* This is the generic lockd callback for async RPC calls
*/
static void nlm4svc_callback_exit(struct rpc_task *task, void *data)
{
dprintk("lockd: %4d callback returned %d\n", task->tk_pid,
-task->tk_status);
}
static void nlm4svc_callback_release(void *data)
{
nlm_release_call(data);
}
static const struct rpc_call_ops nlm4svc_callback_ops = {
.rpc_call_done = nlm4svc_callback_exit,
.rpc_release = nlm4svc_callback_release,
};
/*
* `Async' versions of the above service routines. They aren't really,
* because we send the callback before the reply proper. I hope this
* doesn't break any clients.
*/
static int nlm4svc_callback(struct svc_rqst *rqstp, u32 proc, struct nlm_args *argp,
int (*func)(struct svc_rqst *, struct nlm_args *, struct nlm_res *))
{
struct nlm_host *host;
struct nlm_rqst *call;
int stat;
host = nlmsvc_lookup_host(rqstp,
argp->lock.caller,
argp->lock.len);
if (host == NULL)
return rpc_system_err;
call = nlm_alloc_call(host);
if (call == NULL)
return rpc_system_err;
stat = func(rqstp, argp, &call->a_res);
if (stat != 0) {
nlm_release_call(call);
return stat;
}
call->a_flags = RPC_TASK_ASYNC;
if (nlm_async_reply(call, proc, &nlm4svc_callback_ops) < 0)
return rpc_system_err;
return rpc_success;
}
static int nlm4svc_proc_test_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
void *resp)
{
dprintk("lockd: TEST_MSG called\n");
return nlm4svc_callback(rqstp, NLMPROC_TEST_RES, argp, nlm4svc_proc_test);
}
static int nlm4svc_proc_lock_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
void *resp)
{
dprintk("lockd: LOCK_MSG called\n");
return nlm4svc_callback(rqstp, NLMPROC_LOCK_RES, argp, nlm4svc_proc_lock);
}
static int nlm4svc_proc_cancel_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
void *resp)
{
dprintk("lockd: CANCEL_MSG called\n");
return nlm4svc_callback(rqstp, NLMPROC_CANCEL_RES, argp, nlm4svc_proc_cancel);
}
static int nlm4svc_proc_unlock_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
void *resp)
{
dprintk("lockd: UNLOCK_MSG called\n");
return nlm4svc_callback(rqstp, NLMPROC_UNLOCK_RES, argp, nlm4svc_proc_unlock);
}
static int nlm4svc_proc_granted_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
void *resp)
{
dprintk("lockd: GRANTED_MSG called\n");
return nlm4svc_callback(rqstp, NLMPROC_GRANTED_RES, argp, nlm4svc_proc_granted);
}
/*
* SHARE: create a DOS share or alter existing share.
*/
static int
nlm4svc_proc_share(struct svc_rqst *rqstp, struct nlm_args *argp,
struct nlm_res *resp)
{
struct nlm_host *host;
struct nlm_file *file;
dprintk("lockd: SHARE called\n");
resp->cookie = argp->cookie;
/* Don't accept new lock requests during grace period */
if (nlmsvc_grace_period && !argp->reclaim) {
resp->status = nlm_lck_denied_grace_period;
return rpc_success;
}
/* Obtain client and file */
if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
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);
dprintk("lockd: SHARE status %d\n", ntohl(resp->status));
nlm_release_host(host);
nlm_release_file(file);
return rpc_success;
}
/*
* UNSHARE: Release a DOS share.
*/
static int
nlm4svc_proc_unshare(struct svc_rqst *rqstp, struct nlm_args *argp,
struct nlm_res *resp)
{
struct nlm_host *host;
struct nlm_file *file;
dprintk("lockd: UNSHARE called\n");
resp->cookie = argp->cookie;
/* Don't accept requests during grace period */
if (nlmsvc_grace_period) {
resp->status = nlm_lck_denied_grace_period;
return rpc_success;
}
/* Obtain client and file */
if ((resp->status = nlm4svc_retrieve_args(rqstp, argp, &host, &file)))
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);
dprintk("lockd: UNSHARE status %d\n", ntohl(resp->status));
nlm_release_host(host);
nlm_release_file(file);
return rpc_success;
}
/*
* NM_LOCK: Create an unmonitored lock
*/
static int
nlm4svc_proc_nm_lock(struct svc_rqst *rqstp, struct nlm_args *argp,
struct nlm_res *resp)
{
dprintk("lockd: NM_LOCK called\n");
argp->monitor = 0; /* just clean the monitor flag */
return nlm4svc_proc_lock(rqstp, argp, resp);
}
/*
* FREE_ALL: Release all locks and shares held by client
*/
static int
nlm4svc_proc_free_all(struct svc_rqst *rqstp, struct nlm_args *argp,
void *resp)
{
struct nlm_host *host;
/* Obtain client */
if (nlm4svc_retrieve_args(rqstp, argp, &host, NULL))
return rpc_success;
nlmsvc_free_host_resources(host);
nlm_release_host(host);
return rpc_success;
}
/*
* SM_NOTIFY: private callback from statd (not part of official NLM proto)
*/
static int
nlm4svc_proc_sm_notify(struct svc_rqst *rqstp, struct nlm_reboot *argp,
void *resp)
{
struct sockaddr_in saddr = rqstp->rq_addr;
dprintk("lockd: SM_NOTIFY called\n");
if (saddr.sin_addr.s_addr != htonl(INADDR_LOOPBACK)
|| ntohs(saddr.sin_port) >= 1024) {
printk(KERN_WARNING
"lockd: rejected NSM callback from %08x:%d\n",
ntohl(rqstp->rq_addr.sin_addr.s_addr),
ntohs(rqstp->rq_addr.sin_port));
return rpc_system_err;
}
/* Obtain the host pointer for this NFS server and try to
* reclaim all locks we hold on this server.
*/
memset(&saddr, 0, sizeof(saddr));
saddr.sin_addr.s_addr = argp->addr;
nlm_host_rebooted(&saddr, argp->mon, argp->len, argp->state);
return rpc_success;
}
/*
* client sent a GRANTED_RES, let's remove the associated block
*/
static int
nlm4svc_proc_granted_res(struct svc_rqst *rqstp, struct nlm_res *argp,
void *resp)
{
if (!nlmsvc_ops)
return rpc_success;
dprintk("lockd: GRANTED_RES called\n");
nlmsvc_grant_reply(&argp->cookie, argp->status);
return rpc_success;
}
/*
* NLM Server procedures.
*/
#define nlm4svc_encode_norep nlm4svc_encode_void
#define nlm4svc_decode_norep nlm4svc_decode_void
#define nlm4svc_decode_testres nlm4svc_decode_void
#define nlm4svc_decode_lockres nlm4svc_decode_void
#define nlm4svc_decode_unlockres nlm4svc_decode_void
#define nlm4svc_decode_cancelres nlm4svc_decode_void
#define nlm4svc_decode_grantedres nlm4svc_decode_void
#define nlm4svc_proc_none nlm4svc_proc_null
#define nlm4svc_proc_test_res nlm4svc_proc_null
#define nlm4svc_proc_lock_res nlm4svc_proc_null
#define nlm4svc_proc_cancel_res nlm4svc_proc_null
#define nlm4svc_proc_unlock_res nlm4svc_proc_null
struct nlm_void { int dummy; };
#define PROC(name, xargt, xrest, argt, rest, respsize) \
{ .pc_func = (svc_procfunc) nlm4svc_proc_##name, \
.pc_decode = (kxdrproc_t) nlm4svc_decode_##xargt, \
.pc_encode = (kxdrproc_t) nlm4svc_encode_##xrest, \
.pc_release = NULL, \
.pc_argsize = sizeof(struct nlm_##argt), \
.pc_ressize = sizeof(struct nlm_##rest), \
.pc_xdrressize = respsize, \
}
#define Ck (1+XDR_QUADLEN(NLM_MAXCOOKIELEN)) /* cookie */
#define No (1+1024/4) /* netobj */
#define St 1 /* status */
#define Rg 4 /* range (offset + length) */
struct svc_procedure nlmsvc_procedures4[] = {
PROC(null, void, void, void, void, 1),
PROC(test, testargs, testres, args, res, Ck+St+2+No+Rg),
PROC(lock, lockargs, res, args, res, Ck+St),
PROC(cancel, cancargs, res, args, res, Ck+St),
PROC(unlock, unlockargs, res, args, res, Ck+St),
PROC(granted, testargs, res, args, res, Ck+St),
PROC(test_msg, testargs, norep, args, void, 1),
PROC(lock_msg, lockargs, norep, args, void, 1),
PROC(cancel_msg, cancargs, norep, args, void, 1),
PROC(unlock_msg, unlockargs, norep, args, void, 1),
PROC(granted_msg, testargs, norep, args, void, 1),
PROC(test_res, testres, norep, res, void, 1),
PROC(lock_res, lockres, norep, res, void, 1),
PROC(cancel_res, cancelres, norep, res, void, 1),
PROC(unlock_res, unlockres, norep, res, void, 1),
PROC(granted_res, res, norep, res, void, 1),
/* statd callback */
PROC(sm_notify, reboot, void, reboot, void, 1),
PROC(none, void, void, void, void, 0),
PROC(none, void, void, void, void, 0),
PROC(none, void, void, void, void, 0),
PROC(share, shareargs, shareres, args, res, Ck+St+1),
PROC(unshare, shareargs, shareres, args, res, Ck+St+1),
PROC(nm_lock, lockargs, res, args, res, Ck+St),
PROC(free_all, notify, void, args, void, 1),
};