- 根目录:
- fs
- lockd
- svcproc.c
/*
* linux/fs/lockd/svcproc.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/lockd/lockd.h>
#include <linux/lockd/share.h>
#include <linux/sunrpc/svc_xprt.h>
#define NLMDBG_FACILITY NLMDBG_CLIENT
#ifdef CONFIG_LOCKD_V4
static __be32
cast_to_nlm(__be32 status, u32 vers)
{
/* Note: status is assumed to be in network byte order !!! */
if (vers != 4){
switch (status) {
case nlm_granted:
case nlm_lck_denied:
case nlm_lck_denied_nolocks:
case nlm_lck_blocked:
case nlm_lck_denied_grace_period:
case nlm_drop_reply:
break;
case nlm4_deadlock:
status = nlm_lck_denied;
break;
default:
status = nlm_lck_denied_nolocks;
}
}
return (status);
}
#define cast_status(status) (cast_to_nlm(status, rqstp->rq_vers))
#else
#define cast_status(status) (status)
#endif
/*
* Obtain client and file from arguments
*/
static __be32
nlmsvc_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;
__be32 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) {
error = cast_status(nlm_lookup_file(rqstp, &file, &lock->fh));
if (error != 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:
nlmsvc_release_host(host);
if (error)
return error;
return nlm_lck_denied_nolocks;
}
/*
* NULL: Test for presence of service
*/
static __be32
nlmsvc_proc_null(struct svc_rqst *rqstp, void *argp, void *resp)
{
dprintk("lockd: NULL called\n");
return rpc_success;
}
/*
* TEST: Check for conflicting lock
*/
static __be32
nlmsvc_proc_test(struct svc_rqst *rqstp, struct nlm_args *argp,
struct nlm_res *resp)
{
struct nlm_host *host;
struct nlm_file *file;
__be32 rc = rpc_success;
dprintk("lockd: TEST called\n");
resp->cookie = argp->cookie;
/* Obtain client and file */
if ((resp->status = nlmsvc_retrieve_args(rqstp, argp, &host, &file)))
return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
/* Now check for conflicting locks */
resp->status = cast_status(nlmsvc_testlock(rqstp, file, host, &argp->lock, &resp->lock, &resp->cookie));
if (resp->status == nlm_drop_reply)
rc = rpc_drop_reply;
else
dprintk("lockd: TEST status %d vers %d\n",
ntohl(resp->status), rqstp->rq_vers);
nlmsvc_release_host(host);
nlm_release_file(file);
return rc;
}
static __be32
nlmsvc_proc_lock(struct svc_rqst *rqstp, struct nlm_args *argp,
struct nlm_res *resp)
{
struct nlm_host *host;
struct nlm_file *file;
__be32 rc = rpc_success;
dprintk("lockd: LOCK called\n");
resp->cookie = argp->cookie;
/* Obtain client and file */
if ((resp->status = nlmsvc_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 = cast_status(nlmsvc_lock(rqstp, file, host, &argp->lock,
argp->block, &argp->cookie,
argp->reclaim));
if (resp->status == nlm_drop_reply)
rc = rpc_drop_reply;
else
dprintk("lockd: LOCK status %d\n", ntohl(resp->status));
nlmsvc_release_host(host);
nlm_release_file(file);
return rc;
}
static __be32
nlmsvc_proc_cancel(struct svc_rqst *rqstp, struct nlm_args *argp,
struct nlm_res *resp)
{
struct nlm_host *host;
struct nlm_file *file;
struct net *net = SVC_NET(rqstp);
dprintk("lockd: CANCEL called\n");
resp->cookie = argp->cookie;
/* Don't accept requests during grace period */
if (locks_in_grace(net)) {
resp->status = nlm_lck_denied_grace_period;
return rpc_success;
}
/* Obtain client and file */
if ((resp->status = nlmsvc_retrieve_args(rqstp, argp, &host, &file)))
return resp->status == nlm_drop_reply ? rpc_drop_reply :rpc_success;
/* Try to cancel request. */
resp->status = cast_status(nlmsvc_cancel_blocked(net, file, &argp->lock));
dprintk("lockd: CANCEL status %d\n", ntohl(resp->status));
nlmsvc_release_host(host);
nlm_release_file(file);
return rpc_success;
}
/*
* UNLOCK: release a lock
*/
static __be32
nlmsvc_proc_unlock(struct svc_rqst *rqstp, struct nlm_args *argp,
struct nlm_res *resp)
{
struct nlm_host *host;
struct nlm_file *file;
struct net *net = SVC_NET(rqstp);
dprintk("lockd: UNLOCK called\n");
resp->cookie = argp->cookie;
/* Don't accept new lock requests during grace period */
if (locks_in_grace(net)) {
resp->status = nlm_lck_denied_grace_period;
return rpc_success;
}
/* Obtain client and file */
if ((resp->status = nlmsvc_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 = cast_status(nlmsvc_unlock(net, file, &argp->lock));
dprintk("lockd: UNLOCK status %d\n", ntohl(resp->status));
nlmsvc_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 __be32
nlmsvc_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(svc_addr(rqstp), &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 nlmsvc_callback_exit(struct rpc_task *task, void *data)
{
dprintk("lockd: %5u callback returned %d\n", task->tk_pid,
-task->tk_status);
}
void nlmsvc_release_call(struct nlm_rqst *call)
{
if (!atomic_dec_and_test(&call->a_count))
return;
nlmsvc_release_host(call->a_host);
kfree(call);
}
static void nlmsvc_callback_release(void *data)
{
nlmsvc_release_call(data);
}
static const struct rpc_call_ops nlmsvc_callback_ops = {
.rpc_call_done = nlmsvc_callback_exit,
.rpc_release = nlmsvc_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 __be32 nlmsvc_callback(struct svc_rqst *rqstp, u32 proc, struct nlm_args *argp,
__be32 (*func)(struct svc_rqst *, struct nlm_args *, struct nlm_res *))
{
struct nlm_host *host;
struct nlm_rqst *call;
__be32 stat;
host = nlmsvc_lookup_host(rqstp,
argp->lock.caller,
argp->lock.len);
if (host == NULL)
return rpc_system_err;
call = nlm_alloc_call(host);
nlmsvc_release_host(host);
if (call == NULL)
return rpc_system_err;
stat = func(rqstp, argp, &call->a_res);
if (stat != 0) {
nlmsvc_release_call(call);
return stat;
}
call->a_flags = RPC_TASK_ASYNC;
if (nlm_async_reply(call, proc, &nlmsvc_callback_ops) < 0)
return rpc_system_err;
return rpc_success;
}
static __be32 nlmsvc_proc_test_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
void *resp)
{
dprintk("lockd: TEST_MSG called\n");
return nlmsvc_callback(rqstp, NLMPROC_TEST_RES, argp, nlmsvc_proc_test);
}
static __be32 nlmsvc_proc_lock_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
void *resp)
{
dprintk("lockd: LOCK_MSG called\n");
return nlmsvc_callback(rqstp, NLMPROC_LOCK_RES, argp, nlmsvc_proc_lock);
}
static __be32 nlmsvc_proc_cancel_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
void *resp)
{
dprintk("lockd: CANCEL_MSG called\n");
return nlmsvc_callback(rqstp, NLMPROC_CANCEL_RES, argp, nlmsvc_proc_cancel);
}
static __be32
nlmsvc_proc_unlock_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
void *resp)
{
dprintk("lockd: UNLOCK_MSG called\n");
return nlmsvc_callback(rqstp, NLMPROC_UNLOCK_RES, argp, nlmsvc_proc_unlock);
}
static __be32
nlmsvc_proc_granted_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
void *resp)
{
dprintk("lockd: GRANTED_MSG called\n");
return nlmsvc_callback(rqstp, NLMPROC_GRANTED_RES, argp, nlmsvc_proc_granted);
}
/*
* SHARE: create a DOS share or alter existing share.
*/
static __be32
nlmsvc_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 (locks_in_grace(SVC_NET(rqstp)) && !argp->reclaim) {
resp->status = nlm_lck_denied_grace_period;
return rpc_success;
}
/* Obtain client and file */
if ((resp->status = nlmsvc_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 = cast_status(nlmsvc_share_file(host, file, argp));
dprintk("lockd: SHARE status %d\n", ntohl(resp->status));
nlmsvc_release_host(host);
nlm_release_file(file);
return rpc_success;
}
/*
* UNSHARE: Release a DOS share.
*/
static __be32
nlmsvc_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 (locks_in_grace(SVC_NET(rqstp))) {
resp->status = nlm_lck_denied_grace_period;
return rpc_success;
}
/* Obtain client and file */
if ((resp->status = nlmsvc_retrieve_args(rqstp, argp, &host, &file)))
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));
dprintk("lockd: UNSHARE status %d\n", ntohl(resp->status));
nlmsvc_release_host(host);
nlm_release_file(file);
return rpc_success;
}
/*
* NM_LOCK: Create an unmonitored lock
*/
static __be32
nlmsvc_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 nlmsvc_proc_lock(rqstp, argp, resp);
}
/*
* FREE_ALL: Release all locks and shares held by client
*/
static __be32
nlmsvc_proc_free_all(struct svc_rqst *rqstp, struct nlm_args *argp,
void *resp)
{
struct nlm_host *host;
/* Obtain client */
if (nlmsvc_retrieve_args(rqstp, argp, &host, NULL))
return rpc_success;
nlmsvc_free_host_resources(host);
nlmsvc_release_host(host);
return rpc_success;
}
/*
* SM_NOTIFY: private callback from statd (not part of official NLM proto)
*/
static __be32
nlmsvc_proc_sm_notify(struct svc_rqst *rqstp, struct nlm_reboot *argp,
void *resp)
{
dprintk("lockd: SM_NOTIFY called\n");
if (!nlm_privileged_requester(rqstp)) {
char buf[RPC_MAX_ADDRBUFLEN];
printk(KERN_WARNING "lockd: rejected NSM callback from %s\n",
svc_print_addr(rqstp, buf, sizeof(buf)));
return rpc_system_err;
}
nlm_host_rebooted(SVC_NET(rqstp), argp);
return rpc_success;
}
/*
* client sent a GRANTED_RES, let's remove the associated block
*/
static __be32
nlmsvc_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 nlmsvc_encode_norep nlmsvc_encode_void
#define nlmsvc_decode_norep nlmsvc_decode_void
#define nlmsvc_decode_testres nlmsvc_decode_void
#define nlmsvc_decode_lockres nlmsvc_decode_void
#define nlmsvc_decode_unlockres nlmsvc_decode_void
#define nlmsvc_decode_cancelres nlmsvc_decode_void
#define nlmsvc_decode_grantedres nlmsvc_decode_void
#define nlmsvc_proc_none nlmsvc_proc_null
#define nlmsvc_proc_test_res nlmsvc_proc_null
#define nlmsvc_proc_lock_res nlmsvc_proc_null
#define nlmsvc_proc_cancel_res nlmsvc_proc_null
#define nlmsvc_proc_unlock_res nlmsvc_proc_null
struct nlm_void { int dummy; };
#define PROC(name, xargt, xrest, argt, rest, respsize) \
{ .pc_func = (svc_procfunc) nlmsvc_proc_##name, \
.pc_decode = (kxdrproc_t) nlmsvc_decode_##xargt, \
.pc_encode = (kxdrproc_t) nlmsvc_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 St 1 /* status */
#define No (1+1024/4) /* Net Obj */
#define Rg 2 /* range - offset + size */
struct svc_procedure nlmsvc_procedures[] = {
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, 1),
PROC(none, void, void, void, void, 1),
PROC(none, void, void, void, void, 1),
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, 0),
};