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freebsd-dev/sys/nlm/nlm_prot_impl.c
Rick Macklem 5ee5ec755d Intermittent crashes in the NLM (rpc.lockd) code during system 
shutdown was reporetd via email. The crashes occurred because the
client side NLM would attempt to use its socket after it had been
destroyed. Looking at the code, it would soclose() once the reference
count on the socket handling structure went to 0. Unfortunately,
nlm_host_get_rpc() will simply allocate a new socket handling structure
when none exists and use the now soclose()d socket. Since there doesn't
seem to be a safe way to determine when the socket is no longer needed,
this patch modifies the code so that it never soclose()es the socket.
Since there is only one socket ever created, this does not introduce a
leak when the rpc.lockd is stopped/restarted. The patch also disables
unloading of the nfslockd module, since it is not safe to do so (and
has never been safe to do so, from what I can see).

Reported by:	mav
Tested by:	mav
MFC after:	2 weeks
2013-09-06 23:14:31 +00:00

2428 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 <nfs/nfs_lock.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
*/
static SYSCTL_NODE(_vfs, OID_AUTO, nlm, CTLFLAG_RW, NULL,
"Network Lock Manager");
static 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 flag to indicate the server is already running.
*/
static int nlm_is_running;
/*
* 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_UINT(&host->nh_sysctl, SYSCTL_CHILDREN(oid), OID_AUTO,
"version", CTLFLAG_RD, &host->nh_vers, 0, "");
SYSCTL_ADD_UINT(&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:
inet_ntop(AF_INET,
&((const struct sockaddr_in *) addr)->sin_addr,
tmp, sizeof tmp);
break;
#ifdef INET6
case AF_INET6:
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;
if (nlm_is_running != 0) {
NLM_ERR("NLM: can't start server - "
"it appears to be running already\n");
return (EPERM);
}
if (nlm_socket == NULL) {
memset(&opt, 0, sizeof(opt));
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);
soclose(nlm_socket);
nlm_socket = NULL;
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_is_running = 1;
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:
nlm_is_running = 0;
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.
*/
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);
}
mtx_unlock(&nlm_global_lock);
AUTH_DESTROY(nlm_auth);
return (error);
}
int
sys_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_vnlocked;
};
static int
nlm_get_vfs_state(struct nlm_host *host, struct svc_req *rqstp,
fhandle_t *fhp, struct vfs_state *vs, accmode_t accmode)
{
int error, exflags;
struct ucred *cred = NULL, *credanon = NULL;
memset(vs, 0, sizeof(*vs));
vs->vs_mp = vfs_getvfs(&fhp->fh_fsid);
if (!vs->vs_mp) {
return (ESTALE);
}
/* accmode == 0 means don't check, since it is an unlock. */
if (accmode != 0) {
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, LK_EXCLUSIVE, &vs->vs_vp);
if (error)
goto out;
vs->vs_vnlocked = TRUE;
if (accmode != 0) {
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, accmode, cred, curthread);
/*
* If this failed and accmode != VWRITE, try again with
* VWRITE to maintain backwards compatibility with the
* old code that always used VWRITE.
*/
if (error != 0 && accmode != VWRITE)
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);
}
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;
accmode_t accmode;
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;
}
accmode = argp->exclusive ? VWRITE : VREAD;
error = nlm_get_vfs_state(host, rqstp, &fh, &vs, accmode);
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;
accmode_t accmode;
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;
}
accmode = argp->exclusive ? VWRITE : VREAD;
error = nlm_get_vfs_state(host, rqstp, &fh, &vs, accmode);
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, (accmode_t)0);
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, (accmode_t)0);
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)
{
switch (type) {
case MOD_LOAD:
return (0);
case MOD_UNLOAD:
/* The NLM module cannot be safely unloaded. */
/* FALLTHROUGH */
default:
return (EOPNOTSUPP);
}
}
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, nfslock, 1, 1, 1);
MODULE_VERSION(nfslockd, 1);
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