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freebsd/sys/nlm/nlm_prot_impl.c
Zachary Loafman fbaa591f50 Handle GRANTED_RES messages more gracefully: Send along a grant cookie 
to reference the lock, look up the grant cookie when the GRANTED_RES
comes back. Properly handle the case of an error on the grant. Add a
short expiration window so that granted locks are not freed immediately.

Approved by:        dfr (mentor)
MFC after:          2 weeks
2009-10-07 19:50:14 +00:00

2436 lines
58 KiB
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/*-
* Copyright (c) 2008 Isilon Inc http://www.isilon.com/
* Authors: Doug Rabson <dfr@rabson.org>
* Developed with Red Inc: Alfred Perlstein <alfred@freebsd.org>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include "opt_inet6.h"
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/fail.h>
#include <sys/fcntl.h>
#include <sys/kernel.h>
#include <sys/kthread.h>
#include <sys/lockf.h>
#include <sys/malloc.h>
#include <sys/mount.h>
#if __FreeBSD_version >= 700000
#include <sys/priv.h>
#endif
#include <sys/proc.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/syscall.h>
#include <sys/sysctl.h>
#include <sys/sysent.h>
#include <sys/syslog.h>
#include <sys/sysproto.h>
#include <sys/systm.h>
#include <sys/taskqueue.h>
#include <sys/unistd.h>
#include <sys/vnode.h>
#include <nfs/nfsproto.h>
#include <nfsclient/nfs.h>
#include <nfsclient/nfsnode.h>
#include <nlm/nlm_prot.h>
#include <nlm/sm_inter.h>
#include <nlm/nlm.h>
#include <rpc/rpc_com.h>
#include <rpc/rpcb_prot.h>
MALLOC_DEFINE(M_NLM, "NLM", "Network Lock Manager");
/*
* If a host is inactive (and holds no locks) for this amount of
* seconds, we consider it idle and stop tracking it.
*/
#define NLM_IDLE_TIMEOUT 30
/*
* We check the host list for idle every few seconds.
*/
#define NLM_IDLE_PERIOD 5
/*
* We only look for GRANTED_RES messages for a little while.
*/
#define NLM_EXPIRE_TIMEOUT 10
/*
* Support for sysctl vfs.nlm.sysid
*/
SYSCTL_NODE(_vfs, OID_AUTO, nlm, CTLFLAG_RW, NULL, "Network Lock Manager");
SYSCTL_NODE(_vfs_nlm, OID_AUTO, sysid, CTLFLAG_RW, NULL, "");
/*
* Syscall hooks
*/
static int nlm_syscall_offset = SYS_nlm_syscall;
static struct sysent nlm_syscall_prev_sysent;
#if __FreeBSD_version < 700000
static struct sysent nlm_syscall_sysent = {
(sizeof(struct nlm_syscall_args) / sizeof(register_t)) | SYF_MPSAFE,
(sy_call_t *) nlm_syscall
};
#else
MAKE_SYSENT(nlm_syscall);
#endif
static bool_t nlm_syscall_registered = FALSE;
/*
* Debug level passed in from userland. We also support a sysctl hook
* so that it can be changed on a live system.
*/
static int nlm_debug_level;
SYSCTL_INT(_debug, OID_AUTO, nlm_debug, CTLFLAG_RW, &nlm_debug_level, 0, "");
#define NLM_DEBUG(_level, args...) \
do { \
if (nlm_debug_level >= (_level)) \
log(LOG_DEBUG, args); \
} while(0)
#define NLM_ERR(args...) \
do { \
log(LOG_ERR, args); \
} while(0)
/*
* Grace period handling. The value of nlm_grace_threshold is the
* value of time_uptime after which we are serving requests normally.
*/
static time_t nlm_grace_threshold;
/*
* We check for idle hosts if time_uptime is greater than
* nlm_next_idle_check,
*/
static time_t nlm_next_idle_check;
/*
* A socket to use for RPC - shared by all IPv4 RPC clients.
*/
static struct socket *nlm_socket;
#ifdef INET6
/*
* A socket to use for RPC - shared by all IPv6 RPC clients.
*/
static struct socket *nlm_socket6;
#endif
/*
* An RPC client handle that can be used to communicate with the local
* NSM.
*/
static CLIENT *nlm_nsm;
/*
* An AUTH handle for the server's creds.
*/
static AUTH *nlm_auth;
/*
* A zero timeval for sending async RPC messages.
*/
struct timeval nlm_zero_tv = { 0, 0 };
/*
* The local NSM state number
*/
int nlm_nsm_state;
/*
* A lock to protect the host list and waiting lock list.
*/
static struct mtx nlm_global_lock;
/*
* Locks:
* (l) locked by nh_lock
* (s) only accessed via server RPC which is single threaded
* (g) locked by nlm_global_lock
* (c) const until freeing
* (a) modified using atomic ops
*/
/*
* A pending client-side lock request, stored on the nlm_waiting_locks
* list.
*/
struct nlm_waiting_lock {
TAILQ_ENTRY(nlm_waiting_lock) nw_link; /* (g) */
bool_t nw_waiting; /* (g) */
nlm4_lock nw_lock; /* (c) */
union nfsfh nw_fh; /* (c) */
struct vnode *nw_vp; /* (c) */
};
TAILQ_HEAD(nlm_waiting_lock_list, nlm_waiting_lock);
struct nlm_waiting_lock_list nlm_waiting_locks; /* (g) */
/*
* A pending server-side asynchronous lock request, stored on the
* nh_pending list of the NLM host.
*/
struct nlm_async_lock {
TAILQ_ENTRY(nlm_async_lock) af_link; /* (l) host's list of locks */
struct task af_task; /* (c) async callback details */
void *af_cookie; /* (l) lock manager cancel token */
struct vnode *af_vp; /* (l) vnode to lock */
struct flock af_fl; /* (c) lock details */
struct nlm_host *af_host; /* (c) host which is locking */
CLIENT *af_rpc; /* (c) rpc client to send message */
nlm4_testargs af_granted; /* (c) notification details */
time_t af_expiretime; /* (c) notification time */
};
TAILQ_HEAD(nlm_async_lock_list, nlm_async_lock);
/*
* NLM host.
*/
enum nlm_host_state {
NLM_UNMONITORED,
NLM_MONITORED,
NLM_MONITOR_FAILED,
NLM_RECOVERING
};
struct nlm_rpc {
CLIENT *nr_client; /* (l) RPC client handle */
time_t nr_create_time; /* (l) when client was created */
};
struct nlm_host {
struct mtx nh_lock;
volatile u_int nh_refs; /* (a) reference count */
TAILQ_ENTRY(nlm_host) nh_link; /* (g) global list of hosts */
char nh_caller_name[MAXNAMELEN]; /* (c) printable name of host */
uint32_t nh_sysid; /* (c) our allocaed system ID */
char nh_sysid_string[10]; /* (c) string rep. of sysid */
struct sockaddr_storage nh_addr; /* (s) remote address of host */
struct nlm_rpc nh_srvrpc; /* (l) RPC for server replies */
struct nlm_rpc nh_clntrpc; /* (l) RPC for client requests */
rpcvers_t nh_vers; /* (s) NLM version of host */
int nh_state; /* (s) last seen NSM state of host */
enum nlm_host_state nh_monstate; /* (l) local NSM monitoring state */
time_t nh_idle_timeout; /* (s) Time at which host is idle */
struct sysctl_ctx_list nh_sysctl; /* (c) vfs.nlm.sysid nodes */
uint32_t nh_grantcookie; /* (l) grant cookie counter */
struct nlm_async_lock_list nh_pending; /* (l) pending async locks */
struct nlm_async_lock_list nh_granted; /* (l) granted locks */
struct nlm_async_lock_list nh_finished; /* (l) finished async locks */
};
TAILQ_HEAD(nlm_host_list, nlm_host);
static struct nlm_host_list nlm_hosts; /* (g) */
static uint32_t nlm_next_sysid = 1; /* (g) */
static void nlm_host_unmonitor(struct nlm_host *);
struct nlm_grantcookie {
uint32_t ng_sysid;
uint32_t ng_cookie;
};
static inline uint32_t
ng_sysid(struct netobj *src)
{
return ((struct nlm_grantcookie *)src->n_bytes)->ng_sysid;
}
static inline uint32_t
ng_cookie(struct netobj *src)
{
return ((struct nlm_grantcookie *)src->n_bytes)->ng_cookie;
}
/**********************************************************************/
/*
* Initialise NLM globals.
*/
static void
nlm_init(void *dummy)
{
int error;
mtx_init(&nlm_global_lock, "nlm_global_lock", NULL, MTX_DEF);
TAILQ_INIT(&nlm_waiting_locks);
TAILQ_INIT(&nlm_hosts);
error = syscall_register(&nlm_syscall_offset, &nlm_syscall_sysent,
&nlm_syscall_prev_sysent);
if (error)
NLM_ERR("Can't register NLM syscall\n");
else
nlm_syscall_registered = TRUE;
}
SYSINIT(nlm_init, SI_SUB_LOCK, SI_ORDER_FIRST, nlm_init, NULL);
static void
nlm_uninit(void *dummy)
{
if (nlm_syscall_registered)
syscall_deregister(&nlm_syscall_offset,
&nlm_syscall_prev_sysent);
}
SYSUNINIT(nlm_uninit, SI_SUB_LOCK, SI_ORDER_FIRST, nlm_uninit, NULL);
/*
* Create a netobj from an arbitrary source.
*/
void
nlm_make_netobj(struct netobj *dst, caddr_t src, size_t srcsize,
struct malloc_type *type)
{
dst->n_len = srcsize;
dst->n_bytes = malloc(srcsize, type, M_WAITOK);
memcpy(dst->n_bytes, src, srcsize);
}
/*
* Copy a struct netobj.
*/
void
nlm_copy_netobj(struct netobj *dst, struct netobj *src,
struct malloc_type *type)
{
nlm_make_netobj(dst, src->n_bytes, src->n_len, type);
}
/*
* Create an RPC client handle for the given (address,prog,vers)
* triple using UDP.
*/
static CLIENT *
nlm_get_rpc(struct sockaddr *sa, rpcprog_t prog, rpcvers_t vers)
{
char *wchan = "nlmrcv";
const char* protofmly;
struct sockaddr_storage ss;
struct socket *so;
CLIENT *rpcb;
struct timeval timo;
RPCB parms;
char *uaddr;
enum clnt_stat stat = RPC_SUCCESS;
int rpcvers = RPCBVERS4;
bool_t do_tcp = FALSE;
bool_t tryagain = FALSE;
struct portmap mapping;
u_short port = 0;
/*
* First we need to contact the remote RPCBIND service to find
* the right port.
*/
memcpy(&ss, sa, sa->sa_len);
switch (ss.ss_family) {
case AF_INET:
((struct sockaddr_in *)&ss)->sin_port = htons(111);
protofmly = "inet";
so = nlm_socket;
break;
#ifdef INET6
case AF_INET6:
((struct sockaddr_in6 *)&ss)->sin6_port = htons(111);
protofmly = "inet6";
so = nlm_socket6;
break;
#endif
default:
/*
* Unsupported address family - fail.
*/
return (NULL);
}
rpcb = clnt_dg_create(so, (struct sockaddr *)&ss,
RPCBPROG, rpcvers, 0, 0);
if (!rpcb)
return (NULL);
try_tcp:
parms.r_prog = prog;
parms.r_vers = vers;
if (do_tcp)
parms.r_netid = "tcp";
else
parms.r_netid = "udp";
parms.r_addr = "";
parms.r_owner = "";
/*
* Use the default timeout.
*/
timo.tv_sec = 25;
timo.tv_usec = 0;
again:
switch (rpcvers) {
case RPCBVERS4:
case RPCBVERS:
/*
* Try RPCBIND 4 then 3.
*/
uaddr = NULL;
stat = CLNT_CALL(rpcb, (rpcprog_t) RPCBPROC_GETADDR,
(xdrproc_t) xdr_rpcb, &parms,
(xdrproc_t) xdr_wrapstring, &uaddr, timo);
if (stat == RPC_SUCCESS) {
/*
* We have a reply from the remote RPCBIND - turn it
* into an appropriate address and make a new client
* that can talk to the remote NLM.
*
* XXX fixup IPv6 scope ID.
*/
struct netbuf *a;
a = __rpc_uaddr2taddr_af(ss.ss_family, uaddr);
if (!a) {
tryagain = TRUE;
} else {
tryagain = FALSE;
memcpy(&ss, a->buf, a->len);
free(a->buf, M_RPC);
free(a, M_RPC);
xdr_free((xdrproc_t) xdr_wrapstring, &uaddr);
}
}
if (tryagain || stat == RPC_PROGVERSMISMATCH) {
if (rpcvers == RPCBVERS4)
rpcvers = RPCBVERS;
else if (rpcvers == RPCBVERS)
rpcvers = PMAPVERS;
CLNT_CONTROL(rpcb, CLSET_VERS, &rpcvers);
goto again;
}
break;
case PMAPVERS:
/*
* Try portmap.
*/
mapping.pm_prog = parms.r_prog;
mapping.pm_vers = parms.r_vers;
mapping.pm_prot = do_tcp ? IPPROTO_TCP : IPPROTO_UDP;
mapping.pm_port = 0;
stat = CLNT_CALL(rpcb, (rpcprog_t) PMAPPROC_GETPORT,
(xdrproc_t) xdr_portmap, &mapping,
(xdrproc_t) xdr_u_short, &port, timo);
if (stat == RPC_SUCCESS) {
switch (ss.ss_family) {
case AF_INET:
((struct sockaddr_in *)&ss)->sin_port =
htons(port);
break;
#ifdef INET6
case AF_INET6:
((struct sockaddr_in6 *)&ss)->sin6_port =
htons(port);
break;
#endif
}
}
break;
default:
panic("invalid rpcvers %d", rpcvers);
}
/*
* We may have a positive response from the portmapper, but the NLM
* service was not found. Make sure we received a valid port.
*/
switch (ss.ss_family) {
case AF_INET:
port = ((struct sockaddr_in *)&ss)->sin_port;
break;
#ifdef INET6
case AF_INET6:
port = ((struct sockaddr_in6 *)&ss)->sin6_port;
break;
#endif
}
if (stat != RPC_SUCCESS || !port) {
/*
* If we were able to talk to rpcbind or portmap, but the udp
* variant wasn't available, ask about tcp.
*
* XXX - We could also check for a TCP portmapper, but
* if the host is running a portmapper at all, we should be able
* to hail it over UDP.
*/
if (stat == RPC_SUCCESS && !do_tcp) {
do_tcp = TRUE;
goto try_tcp;
}
/* Otherwise, bad news. */
NLM_ERR("NLM: failed to contact remote rpcbind, "
"stat = %d, port = %d\n", (int) stat, port);
CLNT_DESTROY(rpcb);
return (NULL);
}
if (do_tcp) {
/*
* Destroy the UDP client we used to speak to rpcbind and
* recreate as a TCP client.
*/
struct netconfig *nconf = NULL;
CLNT_DESTROY(rpcb);
switch (ss.ss_family) {
case AF_INET:
nconf = getnetconfigent("tcp");
break;
#ifdef INET6
case AF_INET6:
nconf = getnetconfigent("tcp6");
break;
#endif
}
rpcb = clnt_reconnect_create(nconf, (struct sockaddr *)&ss,
prog, vers, 0, 0);
CLNT_CONTROL(rpcb, CLSET_WAITCHAN, wchan);
rpcb->cl_auth = nlm_auth;
} else {
/*
* Re-use the client we used to speak to rpcbind.
*/
CLNT_CONTROL(rpcb, CLSET_SVC_ADDR, &ss);
CLNT_CONTROL(rpcb, CLSET_PROG, &prog);
CLNT_CONTROL(rpcb, CLSET_VERS, &vers);
CLNT_CONTROL(rpcb, CLSET_WAITCHAN, wchan);
rpcb->cl_auth = nlm_auth;
}
return (rpcb);
}
/*
* This async callback after when an async lock request has been
* granted. We notify the host which initiated the request.
*/
static void
nlm_lock_callback(void *arg, int pending)
{
struct nlm_async_lock *af = (struct nlm_async_lock *) arg;
struct rpc_callextra ext;
NLM_DEBUG(2, "NLM: async lock %p for %s (sysid %d) granted,"
" cookie %d:%d\n", af, af->af_host->nh_caller_name,
af->af_host->nh_sysid, ng_sysid(&af->af_granted.cookie),
ng_cookie(&af->af_granted.cookie));
/*
* Send the results back to the host.
*
* Note: there is a possible race here with nlm_host_notify
* destroying the RPC client. To avoid problems, the first
* thing nlm_host_notify does is to cancel pending async lock
* requests.
*/
memset(&ext, 0, sizeof(ext));
ext.rc_auth = nlm_auth;
if (af->af_host->nh_vers == NLM_VERS4) {
nlm4_granted_msg_4(&af->af_granted,
NULL, af->af_rpc, &ext, nlm_zero_tv);
} else {
/*
* Back-convert to legacy protocol
*/
nlm_testargs granted;
granted.cookie = af->af_granted.cookie;
granted.exclusive = af->af_granted.exclusive;
granted.alock.caller_name =
af->af_granted.alock.caller_name;
granted.alock.fh = af->af_granted.alock.fh;
granted.alock.oh = af->af_granted.alock.oh;
granted.alock.svid = af->af_granted.alock.svid;
granted.alock.l_offset =
af->af_granted.alock.l_offset;
granted.alock.l_len =
af->af_granted.alock.l_len;
nlm_granted_msg_1(&granted,
NULL, af->af_rpc, &ext, nlm_zero_tv);
}
/*
* Move this entry to the nh_granted list.
*/
af->af_expiretime = time_uptime + NLM_EXPIRE_TIMEOUT;
mtx_lock(&af->af_host->nh_lock);
TAILQ_REMOVE(&af->af_host->nh_pending, af, af_link);
TAILQ_INSERT_TAIL(&af->af_host->nh_granted, af, af_link);
mtx_unlock(&af->af_host->nh_lock);
}
/*
* Free an async lock request. The request must have been removed from
* any list.
*/
static void
nlm_free_async_lock(struct nlm_async_lock *af)
{
/*
* Free an async lock.
*/
if (af->af_rpc)
CLNT_RELEASE(af->af_rpc);
xdr_free((xdrproc_t) xdr_nlm4_testargs, &af->af_granted);
if (af->af_vp)
vrele(af->af_vp);
free(af, M_NLM);
}
/*
* Cancel our async request - this must be called with
* af->nh_host->nh_lock held. This is slightly complicated by a
* potential race with our own callback. If we fail to cancel the
* lock, it must already have been granted - we make sure our async
* task has completed by calling taskqueue_drain in this case.
*/
static int
nlm_cancel_async_lock(struct nlm_async_lock *af)
{
struct nlm_host *host = af->af_host;
int error;
mtx_assert(&host->nh_lock, MA_OWNED);
mtx_unlock(&host->nh_lock);
error = VOP_ADVLOCKASYNC(af->af_vp, NULL, F_CANCEL, &af->af_fl,
F_REMOTE, NULL, &af->af_cookie);
if (error) {
/*
* We failed to cancel - make sure our callback has
* completed before we continue.
*/
taskqueue_drain(taskqueue_thread, &af->af_task);
}
mtx_lock(&host->nh_lock);
if (!error) {
NLM_DEBUG(2, "NLM: async lock %p for %s (sysid %d) "
"cancelled\n", af, host->nh_caller_name, host->nh_sysid);
/*
* Remove from the nh_pending list and free now that
* we are safe from the callback.
*/
TAILQ_REMOVE(&host->nh_pending, af, af_link);
mtx_unlock(&host->nh_lock);
nlm_free_async_lock(af);
mtx_lock(&host->nh_lock);
}
return (error);
}
static void
nlm_check_expired_locks(struct nlm_host *host)
{
struct nlm_async_lock *af;
time_t uptime = time_uptime;
mtx_lock(&host->nh_lock);
while ((af = TAILQ_FIRST(&host->nh_granted)) != NULL
&& uptime >= af->af_expiretime) {
NLM_DEBUG(2, "NLM: async lock %p for %s (sysid %d) expired,"
" cookie %d:%d\n", af, af->af_host->nh_caller_name,
af->af_host->nh_sysid, ng_sysid(&af->af_granted.cookie),
ng_cookie(&af->af_granted.cookie));
TAILQ_REMOVE(&host->nh_granted, af, af_link);
mtx_unlock(&host->nh_lock);
nlm_free_async_lock(af);
mtx_lock(&host->nh_lock);
}
while ((af = TAILQ_FIRST(&host->nh_finished)) != NULL) {
TAILQ_REMOVE(&host->nh_finished, af, af_link);
mtx_unlock(&host->nh_lock);
nlm_free_async_lock(af);
mtx_lock(&host->nh_lock);
}
mtx_unlock(&host->nh_lock);
}
/*
* Free resources used by a host. This is called after the reference
* count has reached zero so it doesn't need to worry about locks.
*/
static void
nlm_host_destroy(struct nlm_host *host)
{
mtx_lock(&nlm_global_lock);
TAILQ_REMOVE(&nlm_hosts, host, nh_link);
mtx_unlock(&nlm_global_lock);
if (host->nh_srvrpc.nr_client)
CLNT_RELEASE(host->nh_srvrpc.nr_client);
if (host->nh_clntrpc.nr_client)
CLNT_RELEASE(host->nh_clntrpc.nr_client);
mtx_destroy(&host->nh_lock);
sysctl_ctx_free(&host->nh_sysctl);
free(host, M_NLM);
}
/*
* Thread start callback for client lock recovery
*/
static void
nlm_client_recovery_start(void *arg)
{
struct nlm_host *host = (struct nlm_host *) arg;
NLM_DEBUG(1, "NLM: client lock recovery for %s started\n",
host->nh_caller_name);
nlm_client_recovery(host);
NLM_DEBUG(1, "NLM: client lock recovery for %s completed\n",
host->nh_caller_name);
host->nh_monstate = NLM_MONITORED;
nlm_host_release(host);
kthread_exit();
}
/*
* This is called when we receive a host state change notification. We
* unlock any active locks owned by the host. When rpc.lockd is
* shutting down, this function is called with newstate set to zero
* which allows us to cancel any pending async locks and clear the
* locking state.
*/
static void
nlm_host_notify(struct nlm_host *host, int newstate)
{
struct nlm_async_lock *af;
if (newstate) {
NLM_DEBUG(1, "NLM: host %s (sysid %d) rebooted, new "
"state is %d\n", host->nh_caller_name,
host->nh_sysid, newstate);
}
/*
* Cancel any pending async locks for this host.
*/
mtx_lock(&host->nh_lock);
while ((af = TAILQ_FIRST(&host->nh_pending)) != NULL) {
/*
* nlm_cancel_async_lock will remove the entry from
* nh_pending and free it.
*/
nlm_cancel_async_lock(af);
}
mtx_unlock(&host->nh_lock);
nlm_check_expired_locks(host);
/*
* The host just rebooted - trash its locks.
*/
lf_clearremotesys(host->nh_sysid);
host->nh_state = newstate;
/*
* If we have any remote locks for this host (i.e. it
* represents a remote NFS server that our local NFS client
* has locks for), start a recovery thread.
*/
if (newstate != 0
&& host->nh_monstate != NLM_RECOVERING
&& lf_countlocks(NLM_SYSID_CLIENT | host->nh_sysid) > 0) {
struct thread *td;
host->nh_monstate = NLM_RECOVERING;
refcount_acquire(&host->nh_refs);
kthread_add(nlm_client_recovery_start, host, curproc, &td, 0, 0,
"NFS lock recovery for %s", host->nh_caller_name);
}
}
/*
* Sysctl handler to count the number of locks for a sysid.
*/
static int
nlm_host_lock_count_sysctl(SYSCTL_HANDLER_ARGS)
{
struct nlm_host *host;
int count;
host = oidp->oid_arg1;
count = lf_countlocks(host->nh_sysid);
return sysctl_handle_int(oidp, &count, 0, req);
}
/*
* Sysctl handler to count the number of client locks for a sysid.
*/
static int
nlm_host_client_lock_count_sysctl(SYSCTL_HANDLER_ARGS)
{
struct nlm_host *host;
int count;
host = oidp->oid_arg1;
count = lf_countlocks(NLM_SYSID_CLIENT | host->nh_sysid);
return sysctl_handle_int(oidp, &count, 0, req);
}
/*
* Create a new NLM host.
*/
static struct nlm_host *
nlm_create_host(const char* caller_name)
{
struct nlm_host *host;
struct sysctl_oid *oid;
mtx_assert(&nlm_global_lock, MA_OWNED);
NLM_DEBUG(1, "NLM: new host %s (sysid %d)\n",
caller_name, nlm_next_sysid);
host = malloc(sizeof(struct nlm_host), M_NLM, M_NOWAIT|M_ZERO);
if (!host)
return (NULL);
mtx_init(&host->nh_lock, "nh_lock", NULL, MTX_DEF);
host->nh_refs = 1;
strlcpy(host->nh_caller_name, caller_name, MAXNAMELEN);
host->nh_sysid = nlm_next_sysid++;
snprintf(host->nh_sysid_string, sizeof(host->nh_sysid_string),
"%d", host->nh_sysid);
host->nh_vers = 0;
host->nh_state = 0;
host->nh_monstate = NLM_UNMONITORED;
host->nh_grantcookie = 1;
TAILQ_INIT(&host->nh_pending);
TAILQ_INIT(&host->nh_granted);
TAILQ_INIT(&host->nh_finished);
TAILQ_INSERT_TAIL(&nlm_hosts, host, nh_link);
mtx_unlock(&nlm_global_lock);
sysctl_ctx_init(&host->nh_sysctl);
oid = SYSCTL_ADD_NODE(&host->nh_sysctl,
SYSCTL_STATIC_CHILDREN(_vfs_nlm_sysid),
OID_AUTO, host->nh_sysid_string, CTLFLAG_RD, NULL, "");
SYSCTL_ADD_STRING(&host->nh_sysctl, SYSCTL_CHILDREN(oid), OID_AUTO,
"hostname", CTLFLAG_RD, host->nh_caller_name, 0, "");
SYSCTL_ADD_INT(&host->nh_sysctl, SYSCTL_CHILDREN(oid), OID_AUTO,
"version", CTLFLAG_RD, &host->nh_vers, 0, "");
SYSCTL_ADD_INT(&host->nh_sysctl, SYSCTL_CHILDREN(oid), OID_AUTO,
"monitored", CTLFLAG_RD, &host->nh_monstate, 0, "");
SYSCTL_ADD_PROC(&host->nh_sysctl, SYSCTL_CHILDREN(oid), OID_AUTO,
"lock_count", CTLTYPE_INT | CTLFLAG_RD, host, 0,
nlm_host_lock_count_sysctl, "I", "");
SYSCTL_ADD_PROC(&host->nh_sysctl, SYSCTL_CHILDREN(oid), OID_AUTO,
"client_lock_count", CTLTYPE_INT | CTLFLAG_RD, host, 0,
nlm_host_client_lock_count_sysctl, "I", "");
mtx_lock(&nlm_global_lock);
return (host);
}
/*
* Acquire the next sysid for remote locks not handled by the NLM.
*/
uint32_t
nlm_acquire_next_sysid(void)
{
uint32_t next_sysid;
mtx_lock(&nlm_global_lock);
next_sysid = nlm_next_sysid++;
mtx_unlock(&nlm_global_lock);
return (next_sysid);
}
/*
* Return non-zero if the address parts of the two sockaddrs are the
* same.
*/
static int
nlm_compare_addr(const struct sockaddr *a, const struct sockaddr *b)
{
const struct sockaddr_in *a4, *b4;
#ifdef INET6
const struct sockaddr_in6 *a6, *b6;
#endif
if (a->sa_family != b->sa_family)
return (FALSE);
switch (a->sa_family) {
case AF_INET:
a4 = (const struct sockaddr_in *) a;
b4 = (const struct sockaddr_in *) b;
return !memcmp(&a4->sin_addr, &b4->sin_addr,
sizeof(a4->sin_addr));
#ifdef INET6
case AF_INET6:
a6 = (const struct sockaddr_in6 *) a;
b6 = (const struct sockaddr_in6 *) b;
return !memcmp(&a6->sin6_addr, &b6->sin6_addr,
sizeof(a6->sin6_addr));
#endif
}
return (0);
}
/*
* Check for idle hosts and stop monitoring them. We could also free
* the host structure here, possibly after a larger timeout but that
* would require some care to avoid races with
* e.g. nlm_host_lock_count_sysctl.
*/
static void
nlm_check_idle(void)
{
struct nlm_host *host;
mtx_assert(&nlm_global_lock, MA_OWNED);
if (time_uptime <= nlm_next_idle_check)
return;
nlm_next_idle_check = time_uptime + NLM_IDLE_PERIOD;
TAILQ_FOREACH(host, &nlm_hosts, nh_link) {
if (host->nh_monstate == NLM_MONITORED
&& time_uptime > host->nh_idle_timeout) {
mtx_unlock(&nlm_global_lock);
if (lf_countlocks(host->nh_sysid) > 0
|| lf_countlocks(NLM_SYSID_CLIENT
+ host->nh_sysid)) {
host->nh_idle_timeout =
time_uptime + NLM_IDLE_TIMEOUT;
mtx_lock(&nlm_global_lock);
continue;
}
nlm_host_unmonitor(host);
mtx_lock(&nlm_global_lock);
}
}
}
/*
* Search for an existing NLM host that matches the given name
* (typically the caller_name element of an nlm4_lock). If none is
* found, create a new host. If 'addr' is non-NULL, record the remote
* address of the host so that we can call it back for async
* responses. If 'vers' is greater than zero then record the NLM
* program version to use to communicate with this client.
*/
struct nlm_host *
nlm_find_host_by_name(const char *name, const struct sockaddr *addr,
rpcvers_t vers)
{
struct nlm_host *host;
mtx_lock(&nlm_global_lock);
/*
* The remote host is determined by caller_name.
*/
TAILQ_FOREACH(host, &nlm_hosts, nh_link) {
if (!strcmp(host->nh_caller_name, name))
break;
}
if (!host) {
host = nlm_create_host(name);
if (!host) {
mtx_unlock(&nlm_global_lock);
return (NULL);
}
}
refcount_acquire(&host->nh_refs);
host->nh_idle_timeout = time_uptime + NLM_IDLE_TIMEOUT;
/*
* If we have an address for the host, record it so that we
* can send async replies etc.
*/
if (addr) {
KASSERT(addr->sa_len < sizeof(struct sockaddr_storage),
("Strange remote transport address length"));
/*
* If we have seen an address before and we currently
* have an RPC client handle, make sure the address is
* the same, otherwise discard the client handle.
*/
if (host->nh_addr.ss_len && host->nh_srvrpc.nr_client) {
if (!nlm_compare_addr(
(struct sockaddr *) &host->nh_addr,
addr)
|| host->nh_vers != vers) {
CLIENT *client;
mtx_lock(&host->nh_lock);
client = host->nh_srvrpc.nr_client;
host->nh_srvrpc.nr_client = NULL;
mtx_unlock(&host->nh_lock);
if (client) {
CLNT_RELEASE(client);
}
}
}
memcpy(&host->nh_addr, addr, addr->sa_len);
host->nh_vers = vers;
}
nlm_check_idle();
mtx_unlock(&nlm_global_lock);
return (host);
}
/*
* Search for an existing NLM host that matches the given remote
* address. If none is found, create a new host with the requested
* address and remember 'vers' as the NLM protocol version to use for
* that host.
*/
struct nlm_host *
nlm_find_host_by_addr(const struct sockaddr *addr, int vers)
{
/*
* Fake up a name using inet_ntop. This buffer is
* large enough for an IPv6 address.
*/
char tmp[sizeof "ffff:ffff:ffff:ffff:ffff:ffff:255.255.255.255"];
struct nlm_host *host;
switch (addr->sa_family) {
case AF_INET:
__rpc_inet_ntop(AF_INET,
&((const struct sockaddr_in *) addr)->sin_addr,
tmp, sizeof tmp);
break;
#ifdef INET6
case AF_INET6:
__rpc_inet_ntop(AF_INET6,
&((const struct sockaddr_in6 *) addr)->sin6_addr,
tmp, sizeof tmp);
break;
#endif
default:
strcmp(tmp, "<unknown>");
}
mtx_lock(&nlm_global_lock);
/*
* The remote host is determined by caller_name.
*/
TAILQ_FOREACH(host, &nlm_hosts, nh_link) {
if (nlm_compare_addr(addr,
(const struct sockaddr *) &host->nh_addr))
break;
}
if (!host) {
host = nlm_create_host(tmp);
if (!host) {
mtx_unlock(&nlm_global_lock);
return (NULL);
}
memcpy(&host->nh_addr, addr, addr->sa_len);
host->nh_vers = vers;
}
refcount_acquire(&host->nh_refs);
host->nh_idle_timeout = time_uptime + NLM_IDLE_TIMEOUT;
nlm_check_idle();
mtx_unlock(&nlm_global_lock);
return (host);
}
/*
* Find the NLM host that matches the value of 'sysid'. If none
* exists, return NULL.
*/
static struct nlm_host *
nlm_find_host_by_sysid(int sysid)
{
struct nlm_host *host;
TAILQ_FOREACH(host, &nlm_hosts, nh_link) {
if (host->nh_sysid == sysid) {
refcount_acquire(&host->nh_refs);
return (host);
}
}
return (NULL);
}
void nlm_host_release(struct nlm_host *host)
{
if (refcount_release(&host->nh_refs)) {
/*
* Free the host
*/
nlm_host_destroy(host);
}
}
/*
* Unregister this NLM host with the local NSM due to idleness.
*/
static void
nlm_host_unmonitor(struct nlm_host *host)
{
mon_id smmonid;
sm_stat_res smstat;
struct timeval timo;
enum clnt_stat stat;
NLM_DEBUG(1, "NLM: unmonitoring %s (sysid %d)\n",
host->nh_caller_name, host->nh_sysid);
/*
* We put our assigned system ID value in the priv field to
* make it simpler to find the host if we are notified of a
* host restart.
*/
smmonid.mon_name = host->nh_caller_name;
smmonid.my_id.my_name = "localhost";
smmonid.my_id.my_prog = NLM_PROG;
smmonid.my_id.my_vers = NLM_SM;
smmonid.my_id.my_proc = NLM_SM_NOTIFY;
timo.tv_sec = 25;
timo.tv_usec = 0;
stat = CLNT_CALL(nlm_nsm, SM_UNMON,
(xdrproc_t) xdr_mon, &smmonid,
(xdrproc_t) xdr_sm_stat, &smstat, timo);
if (stat != RPC_SUCCESS) {
NLM_ERR("Failed to contact local NSM - rpc error %d\n", stat);
return;
}
if (smstat.res_stat == stat_fail) {
NLM_ERR("Local NSM refuses to unmonitor %s\n",
host->nh_caller_name);
return;
}
host->nh_monstate = NLM_UNMONITORED;
}
/*
* Register this NLM host with the local NSM so that we can be
* notified if it reboots.
*/
void
nlm_host_monitor(struct nlm_host *host, int state)
{
mon smmon;
sm_stat_res smstat;
struct timeval timo;
enum clnt_stat stat;
if (state && !host->nh_state) {
/*
* This is the first time we have seen an NSM state
* value for this host. We record it here to help
* detect host reboots.
*/
host->nh_state = state;
NLM_DEBUG(1, "NLM: host %s (sysid %d) has NSM state %d\n",
host->nh_caller_name, host->nh_sysid, state);
}
mtx_lock(&host->nh_lock);
if (host->nh_monstate != NLM_UNMONITORED) {
mtx_unlock(&host->nh_lock);
return;
}
host->nh_monstate = NLM_MONITORED;
mtx_unlock(&host->nh_lock);
NLM_DEBUG(1, "NLM: monitoring %s (sysid %d)\n",
host->nh_caller_name, host->nh_sysid);
/*
* We put our assigned system ID value in the priv field to
* make it simpler to find the host if we are notified of a
* host restart.
*/
smmon.mon_id.mon_name = host->nh_caller_name;
smmon.mon_id.my_id.my_name = "localhost";
smmon.mon_id.my_id.my_prog = NLM_PROG;
smmon.mon_id.my_id.my_vers = NLM_SM;
smmon.mon_id.my_id.my_proc = NLM_SM_NOTIFY;
memcpy(smmon.priv, &host->nh_sysid, sizeof(host->nh_sysid));
timo.tv_sec = 25;
timo.tv_usec = 0;
stat = CLNT_CALL(nlm_nsm, SM_MON,
(xdrproc_t) xdr_mon, &smmon,
(xdrproc_t) xdr_sm_stat, &smstat, timo);
if (stat != RPC_SUCCESS) {
NLM_ERR("Failed to contact local NSM - rpc error %d\n", stat);
return;
}
if (smstat.res_stat == stat_fail) {
NLM_ERR("Local NSM refuses to monitor %s\n",
host->nh_caller_name);
mtx_lock(&host->nh_lock);
host->nh_monstate = NLM_MONITOR_FAILED;
mtx_unlock(&host->nh_lock);
return;
}
host->nh_monstate = NLM_MONITORED;
}
/*
* Return an RPC client handle that can be used to talk to the NLM
* running on the given host.
*/
CLIENT *
nlm_host_get_rpc(struct nlm_host *host, bool_t isserver)
{
struct nlm_rpc *rpc;
CLIENT *client;
mtx_lock(&host->nh_lock);
if (isserver)
rpc = &host->nh_srvrpc;
else
rpc = &host->nh_clntrpc;
/*
* We can't hold onto RPC handles for too long - the async
* call/reply protocol used by some NLM clients makes it hard
* to tell when they change port numbers (e.g. after a
* reboot). Note that if a client reboots while it isn't
* holding any locks, it won't bother to notify us. We
* expire the RPC handles after two minutes.
*/
if (rpc->nr_client && time_uptime > rpc->nr_create_time + 2*60) {
client = rpc->nr_client;
rpc->nr_client = NULL;
mtx_unlock(&host->nh_lock);
CLNT_RELEASE(client);
mtx_lock(&host->nh_lock);
}
if (!rpc->nr_client) {
mtx_unlock(&host->nh_lock);
client = nlm_get_rpc((struct sockaddr *)&host->nh_addr,
NLM_PROG, host->nh_vers);
mtx_lock(&host->nh_lock);
if (client) {
if (rpc->nr_client) {
mtx_unlock(&host->nh_lock);
CLNT_DESTROY(client);
mtx_lock(&host->nh_lock);
} else {
rpc->nr_client = client;
rpc->nr_create_time = time_uptime;
}
}
}
client = rpc->nr_client;
if (client)
CLNT_ACQUIRE(client);
mtx_unlock(&host->nh_lock);
return (client);
}
int nlm_host_get_sysid(struct nlm_host *host)
{
return (host->nh_sysid);
}
int
nlm_host_get_state(struct nlm_host *host)
{
return (host->nh_state);
}
void *
nlm_register_wait_lock(struct nlm4_lock *lock, struct vnode *vp)
{
struct nlm_waiting_lock *nw;
nw = malloc(sizeof(struct nlm_waiting_lock), M_NLM, M_WAITOK);
nw->nw_lock = *lock;
memcpy(&nw->nw_fh.fh_bytes, nw->nw_lock.fh.n_bytes,
nw->nw_lock.fh.n_len);
nw->nw_lock.fh.n_bytes = nw->nw_fh.fh_bytes;
nw->nw_waiting = TRUE;
nw->nw_vp = vp;
mtx_lock(&nlm_global_lock);
TAILQ_INSERT_TAIL(&nlm_waiting_locks, nw, nw_link);
mtx_unlock(&nlm_global_lock);
return nw;
}
void
nlm_deregister_wait_lock(void *handle)
{
struct nlm_waiting_lock *nw = handle;
mtx_lock(&nlm_global_lock);
TAILQ_REMOVE(&nlm_waiting_locks, nw, nw_link);
mtx_unlock(&nlm_global_lock);
free(nw, M_NLM);
}
int
nlm_wait_lock(void *handle, int timo)
{
struct nlm_waiting_lock *nw = handle;
int error;
/*
* If the granted message arrived before we got here,
* nw->nw_waiting will be FALSE - in that case, don't sleep.
*/
mtx_lock(&nlm_global_lock);
error = 0;
if (nw->nw_waiting)
error = msleep(nw, &nlm_global_lock, PCATCH, "nlmlock", timo);
TAILQ_REMOVE(&nlm_waiting_locks, nw, nw_link);
if (error) {
/*
* The granted message may arrive after the
* interrupt/timeout but before we manage to lock the
* mutex. Detect this by examining nw_lock.
*/
if (!nw->nw_waiting)
error = 0;
} else {
/*
* If nlm_cancel_wait is called, then error will be
* zero but nw_waiting will still be TRUE. We
* translate this into EINTR.
*/
if (nw->nw_waiting)
error = EINTR;
}
mtx_unlock(&nlm_global_lock);
free(nw, M_NLM);
return (error);
}
void
nlm_cancel_wait(struct vnode *vp)
{
struct nlm_waiting_lock *nw;
mtx_lock(&nlm_global_lock);
TAILQ_FOREACH(nw, &nlm_waiting_locks, nw_link) {
if (nw->nw_vp == vp) {
wakeup(nw);
}
}
mtx_unlock(&nlm_global_lock);
}
/**********************************************************************/
/*
* Syscall interface with userland.
*/
extern void nlm_prog_0(struct svc_req *rqstp, SVCXPRT *transp);
extern void nlm_prog_1(struct svc_req *rqstp, SVCXPRT *transp);
extern void nlm_prog_3(struct svc_req *rqstp, SVCXPRT *transp);
extern void nlm_prog_4(struct svc_req *rqstp, SVCXPRT *transp);
static int
nlm_register_services(SVCPOOL *pool, int addr_count, char **addrs)
{
static rpcvers_t versions[] = {
NLM_SM, NLM_VERS, NLM_VERSX, NLM_VERS4
};
static void (*dispatchers[])(struct svc_req *, SVCXPRT *) = {
nlm_prog_0, nlm_prog_1, nlm_prog_3, nlm_prog_4
};
static const int version_count = sizeof(versions) / sizeof(versions[0]);
SVCXPRT **xprts;
char netid[16];
char uaddr[128];
struct netconfig *nconf;
int i, j, error;
if (!addr_count) {
NLM_ERR("NLM: no service addresses given - can't start server");
return (EINVAL);
}
xprts = malloc(addr_count * sizeof(SVCXPRT *), M_NLM, M_WAITOK|M_ZERO);
for (i = 0; i < version_count; i++) {
for (j = 0; j < addr_count; j++) {
/*
* Create transports for the first version and
* then just register everything else to the
* same transports.
*/
if (i == 0) {
char *up;
error = copyin(&addrs[2*j], &up,
sizeof(char*));
if (error)
goto out;
error = copyinstr(up, netid, sizeof(netid),
NULL);
if (error)
goto out;
error = copyin(&addrs[2*j+1], &up,
sizeof(char*));
if (error)
goto out;
error = copyinstr(up, uaddr, sizeof(uaddr),
NULL);
if (error)
goto out;
nconf = getnetconfigent(netid);
if (!nconf) {
NLM_ERR("Can't lookup netid %s\n",
netid);
error = EINVAL;
goto out;
}
xprts[j] = svc_tp_create(pool, dispatchers[i],
NLM_PROG, versions[i], uaddr, nconf);
if (!xprts[j]) {
NLM_ERR("NLM: unable to create "
"(NLM_PROG, %d).\n", versions[i]);
error = EINVAL;
goto out;
}
freenetconfigent(nconf);
} else {
nconf = getnetconfigent(xprts[j]->xp_netid);
rpcb_unset(NLM_PROG, versions[i], nconf);
if (!svc_reg(xprts[j], NLM_PROG, versions[i],
dispatchers[i], nconf)) {
NLM_ERR("NLM: can't register "
"(NLM_PROG, %d)\n", versions[i]);
error = EINVAL;
goto out;
}
}
}
}
error = 0;
out:
for (j = 0; j < addr_count; j++) {
if (xprts[j])
SVC_RELEASE(xprts[j]);
}
free(xprts, M_NLM);
return (error);
}
/*
* Main server entry point. Contacts the local NSM to get its current
* state and send SM_UNMON_ALL. Registers the NLM services and then
* services requests. Does not return until the server is interrupted
* by a signal.
*/
static int
nlm_server_main(int addr_count, char **addrs)
{
struct thread *td = curthread;
int error;
SVCPOOL *pool = NULL;
struct sockopt opt;
int portlow;
#ifdef INET6
struct sockaddr_in6 sin6;
#endif
struct sockaddr_in sin;
my_id id;
sm_stat smstat;
struct timeval timo;
enum clnt_stat stat;
struct nlm_host *host, *nhost;
struct nlm_waiting_lock *nw;
vop_advlock_t *old_nfs_advlock;
vop_reclaim_t *old_nfs_reclaim;
int v4_used;
#ifdef INET6
int v6_used;
#endif
if (nlm_socket) {
NLM_ERR("NLM: can't start server - "
"it appears to be running already\n");
return (EPERM);
}
memset(&opt, 0, sizeof(opt));
nlm_socket = NULL;
error = socreate(AF_INET, &nlm_socket, SOCK_DGRAM, 0,
td->td_ucred, td);
if (error) {
NLM_ERR("NLM: can't create IPv4 socket - error %d\n", error);
return (error);
}
opt.sopt_dir = SOPT_SET;
opt.sopt_level = IPPROTO_IP;
opt.sopt_name = IP_PORTRANGE;
portlow = IP_PORTRANGE_LOW;
opt.sopt_val = &portlow;
opt.sopt_valsize = sizeof(portlow);
sosetopt(nlm_socket, &opt);
#ifdef INET6
nlm_socket6 = NULL;
error = socreate(AF_INET6, &nlm_socket6, SOCK_DGRAM, 0,
td->td_ucred, td);
if (error) {
NLM_ERR("NLM: can't create IPv6 socket - error %d\n", error);
goto out;
return (error);
}
opt.sopt_dir = SOPT_SET;
opt.sopt_level = IPPROTO_IPV6;
opt.sopt_name = IPV6_PORTRANGE;
portlow = IPV6_PORTRANGE_LOW;
opt.sopt_val = &portlow;
opt.sopt_valsize = sizeof(portlow);
sosetopt(nlm_socket6, &opt);
#endif
nlm_auth = authunix_create(curthread->td_ucred);
#ifdef INET6
memset(&sin6, 0, sizeof(sin6));
sin6.sin6_len = sizeof(sin6);
sin6.sin6_family = AF_INET6;
sin6.sin6_addr = in6addr_loopback;
nlm_nsm = nlm_get_rpc((struct sockaddr *) &sin6, SM_PROG, SM_VERS);
if (!nlm_nsm) {
#endif
memset(&sin, 0, sizeof(sin));
sin.sin_len = sizeof(sin);
sin.sin_family = AF_INET;
sin.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
nlm_nsm = nlm_get_rpc((struct sockaddr *) &sin, SM_PROG,
SM_VERS);
#ifdef INET6
}
#endif
if (!nlm_nsm) {
NLM_ERR("Can't start NLM - unable to contact NSM\n");
error = EINVAL;
goto out;
}
pool = svcpool_create("NLM", NULL);
error = nlm_register_services(pool, addr_count, addrs);
if (error)
goto out;
memset(&id, 0, sizeof(id));
id.my_name = "NFS NLM";
timo.tv_sec = 25;
timo.tv_usec = 0;
stat = CLNT_CALL(nlm_nsm, SM_UNMON_ALL,
(xdrproc_t) xdr_my_id, &id,
(xdrproc_t) xdr_sm_stat, &smstat, timo);
if (stat != RPC_SUCCESS) {
struct rpc_err err;
CLNT_GETERR(nlm_nsm, &err);
NLM_ERR("NLM: unexpected error contacting NSM, "
"stat=%d, errno=%d\n", stat, err.re_errno);
error = EINVAL;
goto out;
}
NLM_DEBUG(1, "NLM: local NSM state is %d\n", smstat.state);
nlm_nsm_state = smstat.state;
old_nfs_advlock = nfs_advlock_p;
nfs_advlock_p = nlm_advlock;
old_nfs_reclaim = nfs_reclaim_p;
nfs_reclaim_p = nlm_reclaim;
svc_run(pool);
error = 0;
nfs_advlock_p = old_nfs_advlock;
nfs_reclaim_p = old_nfs_reclaim;
out:
if (pool)
svcpool_destroy(pool);
/*
* We are finished communicating with the NSM.
*/
if (nlm_nsm) {
CLNT_RELEASE(nlm_nsm);
nlm_nsm = NULL;
}
/*
* Trash all the existing state so that if the server
* restarts, it gets a clean slate. This is complicated by the
* possibility that there may be other threads trying to make
* client locking requests.
*
* First we fake a client reboot notification which will
* cancel any pending async locks and purge remote lock state
* from the local lock manager. We release the reference from
* nlm_hosts to the host (which may remove it from the list
* and free it). After this phase, the only entries in the
* nlm_host list should be from other threads performing
* client lock requests. We arrange to defer closing the
* sockets until the last RPC client handle is released.
*/
v4_used = 0;
#ifdef INET6
v6_used = 0;
#endif
mtx_lock(&nlm_global_lock);
TAILQ_FOREACH(nw, &nlm_waiting_locks, nw_link) {
wakeup(nw);
}
TAILQ_FOREACH_SAFE(host, &nlm_hosts, nh_link, nhost) {
mtx_unlock(&nlm_global_lock);
nlm_host_notify(host, 0);
nlm_host_release(host);
mtx_lock(&nlm_global_lock);
}
TAILQ_FOREACH_SAFE(host, &nlm_hosts, nh_link, nhost) {
mtx_lock(&host->nh_lock);
if (host->nh_srvrpc.nr_client
|| host->nh_clntrpc.nr_client) {
if (host->nh_addr.ss_family == AF_INET)
v4_used++;
#ifdef INET6
if (host->nh_addr.ss_family == AF_INET6)
v6_used++;
#endif
/*
* Note that the rpc over udp code copes
* correctly with the fact that a socket may
* be used by many rpc handles.
*/
if (host->nh_srvrpc.nr_client)
CLNT_CONTROL(host->nh_srvrpc.nr_client,
CLSET_FD_CLOSE, 0);
if (host->nh_clntrpc.nr_client)
CLNT_CONTROL(host->nh_clntrpc.nr_client,
CLSET_FD_CLOSE, 0);
}
mtx_unlock(&host->nh_lock);
}
mtx_unlock(&nlm_global_lock);
AUTH_DESTROY(nlm_auth);
if (!v4_used)
soclose(nlm_socket);
nlm_socket = NULL;
#ifdef INET6
if (!v6_used)
soclose(nlm_socket6);
nlm_socket6 = NULL;
#endif
return (error);
}
int
nlm_syscall(struct thread *td, struct nlm_syscall_args *uap)
{
int error;
#if __FreeBSD_version >= 700000
error = priv_check(td, PRIV_NFS_LOCKD);
#else
error = suser(td);
#endif
if (error)
return (error);
nlm_debug_level = uap->debug_level;
nlm_grace_threshold = time_uptime + uap->grace_period;
nlm_next_idle_check = time_uptime + NLM_IDLE_PERIOD;
return nlm_server_main(uap->addr_count, uap->addrs);
}
/**********************************************************************/
/*
* NLM implementation details, called from the RPC stubs.
*/
void
nlm_sm_notify(struct nlm_sm_status *argp)
{
uint32_t sysid;
struct nlm_host *host;
NLM_DEBUG(3, "nlm_sm_notify(): mon_name = %s\n", argp->mon_name);
memcpy(&sysid, &argp->priv, sizeof(sysid));
host = nlm_find_host_by_sysid(sysid);
if (host) {
nlm_host_notify(host, argp->state);
nlm_host_release(host);
}
}
static void
nlm_convert_to_fhandle_t(fhandle_t *fhp, struct netobj *p)
{
memcpy(fhp, p->n_bytes, sizeof(fhandle_t));
}
struct vfs_state {
struct mount *vs_mp;
struct vnode *vs_vp;
int vs_vfslocked;
int vs_vnlocked;
};
static int
nlm_get_vfs_state(struct nlm_host *host, struct svc_req *rqstp,
fhandle_t *fhp, struct vfs_state *vs)
{
int error, exflags;
struct ucred *cred = NULL, *credanon;
memset(vs, 0, sizeof(*vs));
vs->vs_mp = vfs_getvfs(&fhp->fh_fsid);
if (!vs->vs_mp) {
return (ESTALE);
}
vs->vs_vfslocked = VFS_LOCK_GIANT(vs->vs_mp);
error = VFS_CHECKEXP(vs->vs_mp, (struct sockaddr *)&host->nh_addr,
&exflags, &credanon, NULL, NULL);
if (error)
goto out;
if (exflags & MNT_EXRDONLY || (vs->vs_mp->mnt_flag & MNT_RDONLY)) {
error = EROFS;
goto out;
}
error = VFS_FHTOVP(vs->vs_mp, &fhp->fh_fid, &vs->vs_vp);
if (error)
goto out;
vs->vs_vnlocked = TRUE;
if (!svc_getcred(rqstp, &cred, NULL)) {
error = EINVAL;
goto out;
}
if (cred->cr_uid == 0 || (exflags & MNT_EXPORTANON)) {
crfree(cred);
cred = credanon;
credanon = NULL;
}
/*
* Check cred.
*/
error = VOP_ACCESS(vs->vs_vp, VWRITE, cred, curthread);
if (error)
goto out;
#if __FreeBSD_version < 800011
VOP_UNLOCK(vs->vs_vp, 0, curthread);
#else
VOP_UNLOCK(vs->vs_vp, 0);
#endif
vs->vs_vnlocked = FALSE;
out:
if (cred)
crfree(cred);
if (credanon)
crfree(credanon);
return (error);
}
static void
nlm_release_vfs_state(struct vfs_state *vs)
{
if (vs->vs_vp) {
if (vs->vs_vnlocked)
vput(vs->vs_vp);
else
vrele(vs->vs_vp);
}
if (vs->vs_mp)
vfs_rel(vs->vs_mp);
VFS_UNLOCK_GIANT(vs->vs_vfslocked);
}
static nlm4_stats
nlm_convert_error(int error)
{
if (error == ESTALE)
return nlm4_stale_fh;
else if (error == EROFS)
return nlm4_rofs;
else
return nlm4_failed;
}
int
nlm_do_test(nlm4_testargs *argp, nlm4_testres *result, struct svc_req *rqstp,
CLIENT **rpcp)
{
fhandle_t fh;
struct vfs_state vs;
struct nlm_host *host, *bhost;
int error, sysid;
struct flock fl;
memset(result, 0, sizeof(*result));
memset(&vs, 0, sizeof(vs));
host = nlm_find_host_by_name(argp->alock.caller_name,
svc_getrpccaller(rqstp), rqstp->rq_vers);
if (!host) {
result->stat.stat = nlm4_denied_nolocks;
return (ENOMEM);
}
NLM_DEBUG(3, "nlm_do_test(): caller_name = %s (sysid = %d)\n",
host->nh_caller_name, host->nh_sysid);
nlm_check_expired_locks(host);
sysid = host->nh_sysid;
nlm_convert_to_fhandle_t(&fh, &argp->alock.fh);
nlm_copy_netobj(&result->cookie, &argp->cookie, M_RPC);
if (time_uptime < nlm_grace_threshold) {
result->stat.stat = nlm4_denied_grace_period;
goto out;
}
error = nlm_get_vfs_state(host, rqstp, &fh, &vs);
if (error) {
result->stat.stat = nlm_convert_error(error);
goto out;
}
fl.l_start = argp->alock.l_offset;
fl.l_len = argp->alock.l_len;
fl.l_pid = argp->alock.svid;
fl.l_sysid = sysid;
fl.l_whence = SEEK_SET;
if (argp->exclusive)
fl.l_type = F_WRLCK;
else
fl.l_type = F_RDLCK;
error = VOP_ADVLOCK(vs.vs_vp, NULL, F_GETLK, &fl, F_REMOTE);
if (error) {
result->stat.stat = nlm4_failed;
goto out;
}
if (fl.l_type == F_UNLCK) {
result->stat.stat = nlm4_granted;
} else {
result->stat.stat = nlm4_denied;
result->stat.nlm4_testrply_u.holder.exclusive =
(fl.l_type == F_WRLCK);
result->stat.nlm4_testrply_u.holder.svid = fl.l_pid;
bhost = nlm_find_host_by_sysid(fl.l_sysid);
if (bhost) {
/*
* We don't have any useful way of recording
* the value of oh used in the original lock
* request. Ideally, the test reply would have
* a space for the owning host's name allowing
* our caller's NLM to keep track.
*
* As far as I can see, Solaris uses an eight
* byte structure for oh which contains a four
* byte pid encoded in local byte order and
* the first four bytes of the host
* name. Linux uses a variable length string
* 'pid@hostname' in ascii but doesn't even
* return that in test replies.
*
* For the moment, return nothing in oh
* (already zero'ed above).
*/
nlm_host_release(bhost);
}
result->stat.nlm4_testrply_u.holder.l_offset = fl.l_start;
result->stat.nlm4_testrply_u.holder.l_len = fl.l_len;
}
out:
nlm_release_vfs_state(&vs);
if (rpcp)
*rpcp = nlm_host_get_rpc(host, TRUE);
nlm_host_release(host);
return (0);
}
int
nlm_do_lock(nlm4_lockargs *argp, nlm4_res *result, struct svc_req *rqstp,
bool_t monitor, CLIENT **rpcp)
{
fhandle_t fh;
struct vfs_state vs;
struct nlm_host *host;
int error, sysid;
struct flock fl;
memset(result, 0, sizeof(*result));
memset(&vs, 0, sizeof(vs));
host = nlm_find_host_by_name(argp->alock.caller_name,
svc_getrpccaller(rqstp), rqstp->rq_vers);
if (!host) {
result->stat.stat = nlm4_denied_nolocks;
return (ENOMEM);
}
NLM_DEBUG(3, "nlm_do_lock(): caller_name = %s (sysid = %d)\n",
host->nh_caller_name, host->nh_sysid);
if (monitor && host->nh_state && argp->state
&& host->nh_state != argp->state) {
/*
* The host rebooted without telling us. Trash its
* locks.
*/
nlm_host_notify(host, argp->state);
}
nlm_check_expired_locks(host);
sysid = host->nh_sysid;
nlm_convert_to_fhandle_t(&fh, &argp->alock.fh);
nlm_copy_netobj(&result->cookie, &argp->cookie, M_RPC);
if (time_uptime < nlm_grace_threshold && !argp->reclaim) {
result->stat.stat = nlm4_denied_grace_period;
goto out;
}
error = nlm_get_vfs_state(host, rqstp, &fh, &vs);
if (error) {
result->stat.stat = nlm_convert_error(error);
goto out;
}
fl.l_start = argp->alock.l_offset;
fl.l_len = argp->alock.l_len;
fl.l_pid = argp->alock.svid;
fl.l_sysid = sysid;
fl.l_whence = SEEK_SET;
if (argp->exclusive)
fl.l_type = F_WRLCK;
else
fl.l_type = F_RDLCK;
if (argp->block) {
struct nlm_async_lock *af;
CLIENT *client;
struct nlm_grantcookie cookie;
/*
* First, make sure we can contact the host's NLM.
*/
client = nlm_host_get_rpc(host, TRUE);
if (!client) {
result->stat.stat = nlm4_failed;
goto out;
}
/*
* First we need to check and see if there is an
* existing blocked lock that matches. This could be a
* badly behaved client or an RPC re-send. If we find
* one, just return nlm4_blocked.
*/
mtx_lock(&host->nh_lock);
TAILQ_FOREACH(af, &host->nh_pending, af_link) {
if (af->af_fl.l_start == fl.l_start
&& af->af_fl.l_len == fl.l_len
&& af->af_fl.l_pid == fl.l_pid
&& af->af_fl.l_type == fl.l_type) {
break;
}
}
if (!af) {
cookie.ng_sysid = host->nh_sysid;
cookie.ng_cookie = host->nh_grantcookie++;
}
mtx_unlock(&host->nh_lock);
if (af) {
CLNT_RELEASE(client);
result->stat.stat = nlm4_blocked;
goto out;
}
af = malloc(sizeof(struct nlm_async_lock), M_NLM,
M_WAITOK|M_ZERO);
TASK_INIT(&af->af_task, 0, nlm_lock_callback, af);
af->af_vp = vs.vs_vp;
af->af_fl = fl;
af->af_host = host;
af->af_rpc = client;
/*
* We use M_RPC here so that we can xdr_free the thing
* later.
*/
nlm_make_netobj(&af->af_granted.cookie,
(caddr_t)&cookie, sizeof(cookie), M_RPC);
af->af_granted.exclusive = argp->exclusive;
af->af_granted.alock.caller_name =
strdup(argp->alock.caller_name, M_RPC);
nlm_copy_netobj(&af->af_granted.alock.fh,
&argp->alock.fh, M_RPC);
nlm_copy_netobj(&af->af_granted.alock.oh,
&argp->alock.oh, M_RPC);
af->af_granted.alock.svid = argp->alock.svid;
af->af_granted.alock.l_offset = argp->alock.l_offset;
af->af_granted.alock.l_len = argp->alock.l_len;
/*
* Put the entry on the pending list before calling
* VOP_ADVLOCKASYNC. We do this in case the lock
* request was blocked (returning EINPROGRESS) but
* then granted before we manage to run again. The
* client may receive the granted message before we
* send our blocked reply but thats their problem.
*/
mtx_lock(&host->nh_lock);
TAILQ_INSERT_TAIL(&host->nh_pending, af, af_link);
mtx_unlock(&host->nh_lock);
error = VOP_ADVLOCKASYNC(vs.vs_vp, NULL, F_SETLK, &fl, F_REMOTE,
&af->af_task, &af->af_cookie);
/*
* If the lock completed synchronously, just free the
* tracking structure now.
*/
if (error != EINPROGRESS) {
CLNT_RELEASE(af->af_rpc);
mtx_lock(&host->nh_lock);
TAILQ_REMOVE(&host->nh_pending, af, af_link);
mtx_unlock(&host->nh_lock);
xdr_free((xdrproc_t) xdr_nlm4_testargs,
&af->af_granted);
free(af, M_NLM);
} else {
NLM_DEBUG(2, "NLM: pending async lock %p for %s "
"(sysid %d)\n", af, host->nh_caller_name, sysid);
/*
* Don't vrele the vnode just yet - this must
* wait until either the async callback
* happens or the lock is cancelled.
*/
vs.vs_vp = NULL;
}
} else {
error = VOP_ADVLOCK(vs.vs_vp, NULL, F_SETLK, &fl, F_REMOTE);
}
if (error) {
if (error == EINPROGRESS) {
result->stat.stat = nlm4_blocked;
} else if (error == EDEADLK) {
result->stat.stat = nlm4_deadlck;
} else if (error == EAGAIN) {
result->stat.stat = nlm4_denied;
} else {
result->stat.stat = nlm4_failed;
}
} else {
if (monitor)
nlm_host_monitor(host, argp->state);
result->stat.stat = nlm4_granted;
}
out:
nlm_release_vfs_state(&vs);
if (rpcp)
*rpcp = nlm_host_get_rpc(host, TRUE);
nlm_host_release(host);
return (0);
}
int
nlm_do_cancel(nlm4_cancargs *argp, nlm4_res *result, struct svc_req *rqstp,
CLIENT **rpcp)
{
fhandle_t fh;
struct vfs_state vs;
struct nlm_host *host;
int error, sysid;
struct flock fl;
struct nlm_async_lock *af;
memset(result, 0, sizeof(*result));
memset(&vs, 0, sizeof(vs));
host = nlm_find_host_by_name(argp->alock.caller_name,
svc_getrpccaller(rqstp), rqstp->rq_vers);
if (!host) {
result->stat.stat = nlm4_denied_nolocks;
return (ENOMEM);
}
NLM_DEBUG(3, "nlm_do_cancel(): caller_name = %s (sysid = %d)\n",
host->nh_caller_name, host->nh_sysid);
nlm_check_expired_locks(host);
sysid = host->nh_sysid;
nlm_convert_to_fhandle_t(&fh, &argp->alock.fh);
nlm_copy_netobj(&result->cookie, &argp->cookie, M_RPC);
if (time_uptime < nlm_grace_threshold) {
result->stat.stat = nlm4_denied_grace_period;
goto out;
}
error = nlm_get_vfs_state(host, rqstp, &fh, &vs);
if (error) {
result->stat.stat = nlm_convert_error(error);
goto out;
}
fl.l_start = argp->alock.l_offset;
fl.l_len = argp->alock.l_len;
fl.l_pid = argp->alock.svid;
fl.l_sysid = sysid;
fl.l_whence = SEEK_SET;
if (argp->exclusive)
fl.l_type = F_WRLCK;
else
fl.l_type = F_RDLCK;
/*
* First we need to try and find the async lock request - if
* there isn't one, we give up and return nlm4_denied.
*/
mtx_lock(&host->nh_lock);
TAILQ_FOREACH(af, &host->nh_pending, af_link) {
if (af->af_fl.l_start == fl.l_start
&& af->af_fl.l_len == fl.l_len
&& af->af_fl.l_pid == fl.l_pid
&& af->af_fl.l_type == fl.l_type) {
break;
}
}
if (!af) {
mtx_unlock(&host->nh_lock);
result->stat.stat = nlm4_denied;
goto out;
}
error = nlm_cancel_async_lock(af);
if (error) {
result->stat.stat = nlm4_denied;
} else {
result->stat.stat = nlm4_granted;
}
mtx_unlock(&host->nh_lock);
out:
nlm_release_vfs_state(&vs);
if (rpcp)
*rpcp = nlm_host_get_rpc(host, TRUE);
nlm_host_release(host);
return (0);
}
int
nlm_do_unlock(nlm4_unlockargs *argp, nlm4_res *result, struct svc_req *rqstp,
CLIENT **rpcp)
{
fhandle_t fh;
struct vfs_state vs;
struct nlm_host *host;
int error, sysid;
struct flock fl;
memset(result, 0, sizeof(*result));
memset(&vs, 0, sizeof(vs));
host = nlm_find_host_by_name(argp->alock.caller_name,
svc_getrpccaller(rqstp), rqstp->rq_vers);
if (!host) {
result->stat.stat = nlm4_denied_nolocks;
return (ENOMEM);
}
NLM_DEBUG(3, "nlm_do_unlock(): caller_name = %s (sysid = %d)\n",
host->nh_caller_name, host->nh_sysid);
nlm_check_expired_locks(host);
sysid = host->nh_sysid;
nlm_convert_to_fhandle_t(&fh, &argp->alock.fh);
nlm_copy_netobj(&result->cookie, &argp->cookie, M_RPC);
if (time_uptime < nlm_grace_threshold) {
result->stat.stat = nlm4_denied_grace_period;
goto out;
}
error = nlm_get_vfs_state(host, rqstp, &fh, &vs);
if (error) {
result->stat.stat = nlm_convert_error(error);
goto out;
}
fl.l_start = argp->alock.l_offset;
fl.l_len = argp->alock.l_len;
fl.l_pid = argp->alock.svid;
fl.l_sysid = sysid;
fl.l_whence = SEEK_SET;
fl.l_type = F_UNLCK;
error = VOP_ADVLOCK(vs.vs_vp, NULL, F_UNLCK, &fl, F_REMOTE);
/*
* Ignore the error - there is no result code for failure,
* only for grace period.
*/
result->stat.stat = nlm4_granted;
out:
nlm_release_vfs_state(&vs);
if (rpcp)
*rpcp = nlm_host_get_rpc(host, TRUE);
nlm_host_release(host);
return (0);
}
int
nlm_do_granted(nlm4_testargs *argp, nlm4_res *result, struct svc_req *rqstp,
CLIENT **rpcp)
{
struct nlm_host *host;
struct nlm_waiting_lock *nw;
memset(result, 0, sizeof(*result));
host = nlm_find_host_by_addr(svc_getrpccaller(rqstp), rqstp->rq_vers);
if (!host) {
result->stat.stat = nlm4_denied_nolocks;
return (ENOMEM);
}
nlm_copy_netobj(&result->cookie, &argp->cookie, M_RPC);
result->stat.stat = nlm4_denied;
KFAIL_POINT_CODE(DEBUG_FP, nlm_deny_grant, goto out);
mtx_lock(&nlm_global_lock);
TAILQ_FOREACH(nw, &nlm_waiting_locks, nw_link) {
if (!nw->nw_waiting)
continue;
if (argp->alock.svid == nw->nw_lock.svid
&& argp->alock.l_offset == nw->nw_lock.l_offset
&& argp->alock.l_len == nw->nw_lock.l_len
&& argp->alock.fh.n_len == nw->nw_lock.fh.n_len
&& !memcmp(argp->alock.fh.n_bytes, nw->nw_lock.fh.n_bytes,
nw->nw_lock.fh.n_len)) {
nw->nw_waiting = FALSE;
wakeup(nw);
result->stat.stat = nlm4_granted;
break;
}
}
mtx_unlock(&nlm_global_lock);
out:
if (rpcp)
*rpcp = nlm_host_get_rpc(host, TRUE);
nlm_host_release(host);
return (0);
}
void
nlm_do_granted_res(nlm4_res *argp, struct svc_req *rqstp)
{
struct nlm_host *host = NULL;
struct nlm_async_lock *af = NULL;
int error;
if (argp->cookie.n_len != sizeof(struct nlm_grantcookie)) {
NLM_DEBUG(1, "NLM: bogus grant cookie");
goto out;
}
host = nlm_find_host_by_sysid(ng_sysid(&argp->cookie));
if (!host) {
NLM_DEBUG(1, "NLM: Unknown host rejected our grant");
goto out;
}
mtx_lock(&host->nh_lock);
TAILQ_FOREACH(af, &host->nh_granted, af_link)
if (ng_cookie(&argp->cookie) ==
ng_cookie(&af->af_granted.cookie))
break;
if (af)
TAILQ_REMOVE(&host->nh_granted, af, af_link);
mtx_unlock(&host->nh_lock);
if (!af) {
NLM_DEBUG(1, "NLM: host %s (sysid %d) replied to our grant "
"with unrecognized cookie %d:%d", host->nh_caller_name,
host->nh_sysid, ng_sysid(&argp->cookie),
ng_cookie(&argp->cookie));
goto out;
}
if (argp->stat.stat != nlm4_granted) {
af->af_fl.l_type = F_UNLCK;
error = VOP_ADVLOCK(af->af_vp, NULL, F_UNLCK, &af->af_fl, F_REMOTE);
if (error) {
NLM_DEBUG(1, "NLM: host %s (sysid %d) rejected our grant "
"and we failed to unlock (%d)", host->nh_caller_name,
host->nh_sysid, error);
goto out;
}
NLM_DEBUG(5, "NLM: async lock %p rejected by host %s (sysid %d)",
af, host->nh_caller_name, host->nh_sysid);
} else {
NLM_DEBUG(5, "NLM: async lock %p accepted by host %s (sysid %d)",
af, host->nh_caller_name, host->nh_sysid);
}
out:
if (af)
nlm_free_async_lock(af);
if (host)
nlm_host_release(host);
}
void
nlm_do_free_all(nlm4_notify *argp)
{
struct nlm_host *host, *thost;
TAILQ_FOREACH_SAFE(host, &nlm_hosts, nh_link, thost) {
if (!strcmp(host->nh_caller_name, argp->name))
nlm_host_notify(host, argp->state);
}
}
/*
* Kernel module glue
*/
static int
nfslockd_modevent(module_t mod, int type, void *data)
{
return (0);
}
static moduledata_t nfslockd_mod = {
"nfslockd",
nfslockd_modevent,
NULL,
};
DECLARE_MODULE(nfslockd, nfslockd_mod, SI_SUB_VFS, SI_ORDER_ANY);
/* So that loader and kldload(2) can find us, wherever we are.. */
MODULE_DEPEND(nfslockd, krpc, 1, 1, 1);
MODULE_DEPEND(nfslockd, nfs, 1, 1, 1);
MODULE_VERSION(nfslockd, 1);
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