/* * Copyright (c) 2002-2005 Apple Computer, Inc. All rights reserved. * * @APPLE_LICENSE_OSREFERENCE_HEADER_START@ * * This file contains Original Code and/or Modifications of Original Code * as defined in and that are subject to the Apple Public Source License * Version 2.0 (the 'License'). You may not use this file except in * compliance with the License. The rights granted to you under the * License may not be used to create, or enable the creation or * redistribution of, unlawful or unlicensed copies of an Apple operating * system, or to circumvent, violate, or enable the circumvention or * violation of, any terms of an Apple operating system software license * agreement. * * Please obtain a copy of the License at * http://www.opensource.apple.com/apsl/ and read it before using this * file. * * The Original Code and all software distributed under the License are * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. * Please see the License for the specific language governing rights and * limitations under the License. * * @APPLE_LICENSE_OSREFERENCE_HEADER_END@ */ /*- * Copyright (c) 1997 Berkeley Software Design, Inc. All rights reserved. * * 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. * 3. Berkeley Software Design Inc's name may not be used to endorse or * promote products derived from this software without specific prior * written permission. * * THIS SOFTWARE IS PROVIDED BY BERKELEY SOFTWARE DESIGN INC ``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 BERKELEY SOFTWARE DESIGN INC 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. * * from BSDI nfs_lock.c,v 2.4 1998/12/14 23:49:56 jch Exp */ #include #include #include #include #include /* for hz */ #include #include #include /* for hz */ /* Must come after sys/malloc.h */ #include #include #include /* for p_start */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #define OFF_MAX QUAD_MAX /* * globals for managing the lockd fifo */ vnode_t nfslockdvnode = 0; int nfslockdwaiting = 0; time_t nfslockdstarttimeout = 0; int nfslockdfifolock = 0; #define NFSLOCKDFIFOLOCK_LOCKED 1 #define NFSLOCKDFIFOLOCK_WANT 2 /* * pending lock request messages are kept in this queue which is * kept sorted by transaction ID (xid). */ uint64_t nfs_lockxid = 0; LOCKD_MSG_QUEUE nfs_pendlockq; /* * This structure is used to identify processes which have acquired NFS locks. * Knowing which processes have ever acquired locks allows us to short-circuit * unlock requests for processes that have never had an NFS file lock. Thus * avoiding a costly and unnecessary lockd request. */ struct nfs_lock_pid { TAILQ_ENTRY(nfs_lock_pid) lp_lru; /* LRU list */ LIST_ENTRY(nfs_lock_pid) lp_hash; /* hash chain */ int lp_valid; /* valid entry? */ int lp_time; /* last time seen valid */ pid_t lp_pid; /* The process ID. */ struct timeval lp_pid_start; /* Start time of process id */ }; #define NFS_LOCK_PID_HASH_SIZE 64 // XXX tune me #define NFS_LOCK_PID_HASH(pid) \ (&nfs_lock_pid_hash_tbl[(pid) & nfs_lock_pid_hash]) LIST_HEAD(, nfs_lock_pid) *nfs_lock_pid_hash_tbl; TAILQ_HEAD(, nfs_lock_pid) nfs_lock_pid_lru; u_long nfs_lock_pid_hash; int nfs_lock_pid_lock; /* * initialize global nfs lock state */ void nfs_lockinit(void) { TAILQ_INIT(&nfs_pendlockq); nfs_lock_pid_lock = 0; nfs_lock_pid_hash_tbl = hashinit(NFS_LOCK_PID_HASH_SIZE, M_TEMP, &nfs_lock_pid_hash); TAILQ_INIT(&nfs_lock_pid_lru); } /* * insert a lock request message into the pending queue */ static inline void nfs_lockdmsg_enqueue(LOCKD_MSG_REQUEST *msgreq) { LOCKD_MSG_REQUEST *mr; mr = TAILQ_LAST(&nfs_pendlockq, nfs_lock_msg_queue); if (!mr || (msgreq->lmr_msg.lm_xid > mr->lmr_msg.lm_xid)) { /* fast path: empty queue or new largest xid */ TAILQ_INSERT_TAIL(&nfs_pendlockq, msgreq, lmr_next); return; } /* slow path: need to walk list to find insertion point */ while (mr && (msgreq->lmr_msg.lm_xid > mr->lmr_msg.lm_xid)) { mr = TAILQ_PREV(mr, nfs_lock_msg_queue, lmr_next); } if (mr) { TAILQ_INSERT_AFTER(&nfs_pendlockq, mr, msgreq, lmr_next); } else { TAILQ_INSERT_HEAD(&nfs_pendlockq, msgreq, lmr_next); } } /* * remove a lock request message from the pending queue */ static inline void nfs_lockdmsg_dequeue(LOCKD_MSG_REQUEST *msgreq) { TAILQ_REMOVE(&nfs_pendlockq, msgreq, lmr_next); } /* * find a pending lock request message by xid * * We search from the head of the list assuming that the message we're * looking for is for an older request (because we have an answer to it). * This assumes that lock request will be answered primarily in FIFO order. * However, this may not be the case if there are blocked requests. We may * want to move blocked requests to a separate queue (but that'll complicate * duplicate xid checking). */ static inline LOCKD_MSG_REQUEST * nfs_lockdmsg_find_by_xid(uint64_t lockxid) { LOCKD_MSG_REQUEST *mr; TAILQ_FOREACH(mr, &nfs_pendlockq, lmr_next) { if (mr->lmr_msg.lm_xid == lockxid) return mr; if (mr->lmr_msg.lm_xid > lockxid) return NULL; } return mr; } /* * Because we can't depend on nlm_granted messages containing the same * cookie we sent with the original lock request, we need code test if * an nlm_granted answer matches the lock request. We also need code * that can find a lockd message based solely on the nlm_granted answer. */ /* * compare lockd message to answer * * returns 0 on equality and 1 if different */ static inline int nfs_lockdmsg_compare_to_answer(LOCKD_MSG_REQUEST *msgreq, struct lockd_ans *ansp) { if (!(ansp->la_flags & LOCKD_ANS_LOCK_INFO)) return 1; if (msgreq->lmr_msg.lm_fl.l_pid != ansp->la_pid) return 1; if (msgreq->lmr_msg.lm_fl.l_start != ansp->la_start) return 1; if (msgreq->lmr_msg.lm_fl.l_len != ansp->la_len) return 1; if (msgreq->lmr_msg.lm_fh_len != ansp->la_fh_len) return 1; if (bcmp(msgreq->lmr_msg.lm_fh, ansp->la_fh, ansp->la_fh_len)) return 1; return 0; } /* * find a pending lock request message based on the lock info provided * in the lockd_ans/nlm_granted data. We need this because we can't * depend on nlm_granted messages containing the same cookie we sent * with the original lock request. * * We search from the head of the list assuming that the message we're * looking for is for an older request (because we have an answer to it). * This assumes that lock request will be answered primarily in FIFO order. * However, this may not be the case if there are blocked requests. We may * want to move blocked requests to a separate queue (but that'll complicate * duplicate xid checking). */ static inline LOCKD_MSG_REQUEST * nfs_lockdmsg_find_by_answer(struct lockd_ans *ansp) { LOCKD_MSG_REQUEST *mr; if (!(ansp->la_flags & LOCKD_ANS_LOCK_INFO)) return NULL; TAILQ_FOREACH(mr, &nfs_pendlockq, lmr_next) { if (!nfs_lockdmsg_compare_to_answer(mr, ansp)) break; } return mr; } /* * return the next unique lock request transaction ID */ static inline uint64_t nfs_lockxid_get(void) { LOCKD_MSG_REQUEST *mr; /* derive initial lock xid from system time */ if (!nfs_lockxid) { /* * Note: it's OK if this code inits nfs_lockxid to 0 (for example, * due to a broken clock) because we immediately increment it * and we guarantee to never use xid 0. So, nfs_lockxid should only * ever be 0 the first time this function is called. */ struct timeval tv; microtime(&tv); nfs_lockxid = (uint64_t)tv.tv_sec << 12; } /* make sure we get a unique xid */ do { /* Skip zero xid if it should ever happen. */ if (++nfs_lockxid == 0) nfs_lockxid++; if (!(mr = TAILQ_LAST(&nfs_pendlockq, nfs_lock_msg_queue)) || (mr->lmr_msg.lm_xid < nfs_lockxid)) { /* fast path: empty queue or new largest xid */ break; } /* check if xid is already in use */ } while (nfs_lockdmsg_find_by_xid(nfs_lockxid)); return nfs_lockxid; } /* * Check the nfs_lock_pid hash table for an entry and, if requested, * add the entry if it is not found. * * (Also, if adding, try to clean up some stale entries.) */ static int nfs_lock_pid_check(proc_t p, int addflag, vnode_t vp) { struct nfs_lock_pid *lp, *lplru, *lplru_next; proc_t plru; int error = 0; struct timeval now; /* lock hash */ loop: if (nfs_lock_pid_lock) { struct nfsmount *nmp = VFSTONFS(vnode_mount(vp)); while (nfs_lock_pid_lock) { nfs_lock_pid_lock = -1; tsleep(&nfs_lock_pid_lock, PCATCH, "nfslockpid", 0); if ((error = nfs_sigintr(nmp, NULL, p))) return (error); } goto loop; } nfs_lock_pid_lock = 1; /* Search hash chain */ error = ENOENT; lp = NFS_LOCK_PID_HASH(proc_pid(p))->lh_first; for (; lp != NULL; lp = lp->lp_hash.le_next) if (lp->lp_pid == proc_pid(p)) { /* found pid... */ if (timevalcmp(&lp->lp_pid_start, &p->p_stats->p_start, ==)) { /* ...and it's valid */ /* move to tail of LRU */ TAILQ_REMOVE(&nfs_lock_pid_lru, lp, lp_lru); microuptime(&now); lp->lp_time = now.tv_sec; TAILQ_INSERT_TAIL(&nfs_lock_pid_lru, lp, lp_lru); error = 0; break; } /* ...but it's no longer valid */ /* remove from hash, invalidate, and move to lru head */ LIST_REMOVE(lp, lp_hash); lp->lp_valid = 0; TAILQ_REMOVE(&nfs_lock_pid_lru, lp, lp_lru); TAILQ_INSERT_HEAD(&nfs_lock_pid_lru, lp, lp_lru); lp = NULL; break; } /* if we didn't find it (valid) and we've been asked to add it */ if ((error == ENOENT) && addflag) { /* scan lru list for invalid, stale entries to reuse/free */ int lrucnt = 0; microuptime(&now); for (lplru = TAILQ_FIRST(&nfs_lock_pid_lru); lplru; lplru = lplru_next) { lplru_next = TAILQ_NEXT(lplru, lp_lru); if (lplru->lp_valid && (lplru->lp_time >= (now.tv_sec - 2))) { /* * If the oldest LRU entry is relatively new, then don't * bother scanning any further. */ break; } /* remove entry from LRU, and check if it's still in use */ TAILQ_REMOVE(&nfs_lock_pid_lru, lplru, lp_lru); if (!lplru->lp_valid || !(plru = pfind(lplru->lp_pid)) || timevalcmp(&lplru->lp_pid_start, &plru->p_stats->p_start, !=)) { /* no longer in use */ LIST_REMOVE(lplru, lp_hash); if (!lp) { /* we'll reuse this one */ lp = lplru; } else { /* we can free this one */ FREE(lplru, M_TEMP); } } else { /* still in use */ lplru->lp_time = now.tv_sec; TAILQ_INSERT_TAIL(&nfs_lock_pid_lru, lplru, lp_lru); } /* don't check too many entries at once */ if (++lrucnt > 8) break; } if (!lp) { /* we need to allocate a new one */ MALLOC(lp, struct nfs_lock_pid *, sizeof(struct nfs_lock_pid), M_TEMP, M_WAITOK | M_ZERO); } if (!lp) { error = ENOMEM; } else { /* (re)initialize nfs_lock_pid info */ lp->lp_pid = proc_pid(p); lp->lp_pid_start = p->p_stats->p_start; /* insert pid in hash */ LIST_INSERT_HEAD(NFS_LOCK_PID_HASH(lp->lp_pid), lp, lp_hash); lp->lp_valid = 1; lp->lp_time = now.tv_sec; TAILQ_INSERT_TAIL(&nfs_lock_pid_lru, lp, lp_lru); error = 0; } } /* unlock hash */ if (nfs_lock_pid_lock < 0) { nfs_lock_pid_lock = 0; wakeup(&nfs_lock_pid_lock); } else nfs_lock_pid_lock = 0; return (error); } /* * nfs_advlock -- * NFS advisory byte-level locks. */ int nfs_dolock(struct vnop_advlock_args *ap) /* struct vnop_advlock_args { struct vnodeop_desc *a_desc; vnode_t a_vp; caddr_t a_id; int a_op; struct flock *a_fl; int a_flags; vfs_context_t a_context; }; */ { LOCKD_MSG_REQUEST msgreq; LOCKD_MSG *msg; vnode_t vp, wvp; struct nfsnode *np; int error, error1; struct flock *fl; int fmode, ioflg; struct nfsmount *nmp; struct nfs_vattr nvattr; off_t start, end; struct timeval now; int timeo, endtime, lastmsg, wentdown = 0; int lockpidcheck; kauth_cred_t cred; proc_t p; struct sockaddr *saddr; p = vfs_context_proc(ap->a_context); cred = vfs_context_ucred(ap->a_context); vp = ap->a_vp; fl = ap->a_fl; np = VTONFS(vp); nmp = VFSTONFS(vnode_mount(vp)); if (!nmp) return (ENXIO); if (nmp->nm_flag & NFSMNT_NOLOCKS) return (ENOTSUP); /* * The NLM protocol doesn't allow the server to return an error * on ranges, so we do it. Pre LFS (Large File Summit) * standards required EINVAL for the range errors. More recent * standards use EOVERFLOW, but their EINVAL wording still * encompasses these errors. * Any code sensitive to this is either: * 1) written pre-LFS and so can handle only EINVAL, or * 2) written post-LFS and thus ought to be tolerant of pre-LFS * implementations. * Since returning EOVERFLOW certainly breaks 1), we return EINVAL. */ if (fl->l_whence != SEEK_END) { if ((fl->l_whence != SEEK_CUR && fl->l_whence != SEEK_SET) || fl->l_start < 0 || (fl->l_len > 0 && fl->l_len - 1 > OFF_MAX - fl->l_start) || (fl->l_len < 0 && fl->l_start + fl->l_len < 0)) return (EINVAL); } /* * If daemon is running take a ref on its fifo vnode */ if (!(wvp = nfslockdvnode)) { if (!nfslockdwaiting && !nfslockdstarttimeout) return (ENOTSUP); /* * Don't wake lock daemon if it hasn't been started yet and * this is an unlock request (since we couldn't possibly * actually have a lock on the file). This could be an * uninformed unlock request due to closef()'s behavior of doing * unlocks on all files if a process has had a lock on ANY file. */ if (!nfslockdvnode && (fl->l_type == F_UNLCK)) return (EINVAL); microuptime(&now); if (nfslockdwaiting) { /* wake up lock daemon */ nfslockdstarttimeout = now.tv_sec + 60; (void)wakeup((void *)&nfslockdwaiting); } /* wait on nfslockdvnode for a while to allow daemon to start */ while (!nfslockdvnode && (now.tv_sec < nfslockdstarttimeout)) { error = tsleep((void *)&nfslockdvnode, PCATCH | PUSER, "lockdstart", 2*hz); if (error && (error != EWOULDBLOCK)) return (error); /* check that we still have our mount... */ /* ...and that we still support locks */ nmp = VFSTONFS(vnode_mount(vp)); if (!nmp) return (ENXIO); if (nmp->nm_flag & NFSMNT_NOLOCKS) return (ENOTSUP); if (!error) break; microuptime(&now); } /* * check for nfslockdvnode * If it hasn't started by now, there's a problem. */ if (!(wvp = nfslockdvnode)) return (ENOTSUP); } error = vnode_getwithref(wvp); if (error) return (ENOTSUP); error = vnode_ref(wvp); if (error) { vnode_put(wvp); return (ENOTSUP); } /* * Need to check if this process has successfully acquired an NFS lock before. * If not, and this is an unlock request we can simply return success here. */ lockpidcheck = nfs_lock_pid_check(p, 0, vp); if (lockpidcheck) { if (lockpidcheck != ENOENT) { vnode_rele(wvp); vnode_put(wvp); return (lockpidcheck); } if (ap->a_op == F_UNLCK) { vnode_rele(wvp); vnode_put(wvp); return (0); } } /* * The NFS Lock Manager protocol doesn't directly handle * negative lengths or SEEK_END, so we need to normalize * things here where we have all the info. * (Note: SEEK_CUR is already adjusted for at this point) */ /* Convert the flock structure into a start and end. */ switch (fl->l_whence) { case SEEK_SET: case SEEK_CUR: /* * Caller is responsible for adding any necessary offset * to fl->l_start when SEEK_CUR is used. */ start = fl->l_start; break; case SEEK_END: /* need to flush, and refetch attributes to make */ /* sure we have the correct end of file offset */ if (np->n_flag & NMODIFIED) { NATTRINVALIDATE(np); error = nfs_vinvalbuf(vp, V_SAVE, cred, p, 1); if (error) { vnode_rele(wvp); vnode_put(wvp); return (error); } } NATTRINVALIDATE(np); error = nfs_getattr(vp, &nvattr, cred, p); if (error) { vnode_rele(wvp); vnode_put(wvp); return (error); } start = np->n_size + fl->l_start; break; default: vnode_rele(wvp); vnode_put(wvp); return (EINVAL); } if (fl->l_len == 0) end = -1; else if (fl->l_len > 0) end = start + fl->l_len - 1; else { /* l_len is negative */ end = start - 1; start += fl->l_len; } if (start < 0) { vnode_rele(wvp); vnode_put(wvp); return (EINVAL); } if (!NFS_ISV3(vp) && ((start >= 0x80000000) || (end >= 0x80000000))) { vnode_rele(wvp); vnode_put(wvp); return (EINVAL); } /* * Fill in the information structure. */ msgreq.lmr_answered = 0; msgreq.lmr_errno = 0; msgreq.lmr_saved_errno = 0; msg = &msgreq.lmr_msg; msg->lm_version = LOCKD_MSG_VERSION; msg->lm_flags = 0; msg->lm_fl = *fl; msg->lm_fl.l_start = start; if (end != -1) msg->lm_fl.l_len = end - start + 1; msg->lm_fl.l_pid = proc_pid(p); if (ap->a_flags & F_WAIT) msg->lm_flags |= LOCKD_MSG_BLOCK; if (ap->a_op == F_GETLK) msg->lm_flags |= LOCKD_MSG_TEST; nmp = VFSTONFS(vnode_mount(vp)); if (!nmp) { vnode_rele(wvp); vnode_put(wvp); return (ENXIO); } saddr = mbuf_data(nmp->nm_nam); bcopy(saddr, &msg->lm_addr, min(sizeof msg->lm_addr, saddr->sa_len)); msg->lm_fh_len = NFS_ISV3(vp) ? VTONFS(vp)->n_fhsize : NFSX_V2FH; bcopy(VTONFS(vp)->n_fhp, msg->lm_fh, msg->lm_fh_len); if (NFS_ISV3(vp)) msg->lm_flags |= LOCKD_MSG_NFSV3; cru2x(cred, &msg->lm_cred); microuptime(&now); lastmsg = now.tv_sec - ((nmp->nm_tprintf_delay) - (nmp->nm_tprintf_initial_delay)); fmode = FFLAGS(O_WRONLY); if ((error = VNOP_OPEN(wvp, fmode, ap->a_context))) { vnode_rele(wvp); vnode_put(wvp); return (error); } vnode_lock(wvp); ++wvp->v_writecount; vnode_unlock(wvp); /* allocate unique xid */ msg->lm_xid = nfs_lockxid_get(); nfs_lockdmsg_enqueue(&msgreq); timeo = 2*hz; #define IO_NOMACCHECK 0; ioflg = IO_UNIT | IO_NOMACCHECK; for (;;) { error = 0; while (nfslockdfifolock & NFSLOCKDFIFOLOCK_LOCKED) { nfslockdfifolock |= NFSLOCKDFIFOLOCK_WANT; error = tsleep((void *)&nfslockdfifolock, PCATCH | PUSER, "lockdfifo", 20*hz); if (error) break; } if (error) break; nfslockdfifolock |= NFSLOCKDFIFOLOCK_LOCKED; error = vn_rdwr(UIO_WRITE, wvp, (caddr_t)msg, sizeof(*msg), 0, UIO_SYSSPACE32, ioflg, proc_ucred(kernproc), NULL, p); nfslockdfifolock &= ~NFSLOCKDFIFOLOCK_LOCKED; if (nfslockdfifolock & NFSLOCKDFIFOLOCK_WANT) { nfslockdfifolock &= ~NFSLOCKDFIFOLOCK_WANT; wakeup((void *)&nfslockdfifolock); } if (error && (((ioflg & IO_NDELAY) == 0) || error != EAGAIN)) { break; } /* * Always wait for an answer. Not waiting for unlocks could * cause a lock to be left if the unlock request gets dropped. */ /* * Retry if it takes too long to get a response. * * The timeout numbers were picked out of thin air... they start * at 2 and double each timeout with a max of 60 seconds. * * In order to maintain responsiveness, we pass a small timeout * to tsleep and calculate the timeouts ourselves. This allows * us to pick up on mount changes quicker. */ wait_for_granted: error = EWOULDBLOCK; microuptime(&now); if ((timeo/hz) > 0) endtime = now.tv_sec + timeo/hz; else endtime = now.tv_sec + 1; while (now.tv_sec < endtime) { error = tsleep((void *)&msgreq, PCATCH | PUSER, "lockd", 2*hz); if (msgreq.lmr_answered) { /* * Note: it's possible to have a lock granted at * essentially the same time that we get interrupted. * Since the lock may be granted, we can't return an * error from this request or we might not unlock the * lock that's been granted. */ error = 0; break; } if (error != EWOULDBLOCK) break; /* check that we still have our mount... */ /* ...and that we still support locks */ nmp = VFSTONFS(vnode_mount(vp)); if (!nmp || (nmp->nm_flag & NFSMNT_NOLOCKS)) break; /* * If the mount is hung and we've requested not to hang * on remote filesystems, then bail now. */ if ((p != NULL) && ((proc_noremotehang(p)) != 0) && ((nmp->nm_state & (NFSSTA_TIMEO|NFSSTA_LOCKTIMEO)) != 0)) { if (fl->l_type == F_UNLCK) printf("nfs_dolock: aborting unlock request " "due to timeout (noremotehang)\n"); error = EIO; break; } microuptime(&now); } if (error) { /* check that we still have our mount... */ nmp = VFSTONFS(vnode_mount(vp)); if (!nmp) { if (error == EWOULDBLOCK) error = ENXIO; break; } /* ...and that we still support locks */ if (nmp->nm_flag & NFSMNT_NOLOCKS) { if (error == EWOULDBLOCK) error = ENOTSUP; break; } if ((error == ENOTSUP) && (nmp->nm_state & NFSSTA_LOCKSWORK)) { /* * We have evidence that locks work, yet lockd * returned ENOTSUP. This is probably because * it was unable to contact the server's lockd to * send it the request. * * Because we know locks work, we'll consider * this failure to be a timeout. */ error = EWOULDBLOCK; } if (error != EWOULDBLOCK) { /* * We're going to bail on this request. * If we were a blocked lock request, send a cancel. */ if ((msgreq.lmr_errno == EINPROGRESS) && !(msg->lm_flags & LOCKD_MSG_CANCEL)) { /* set this request up as a cancel */ msg->lm_flags |= LOCKD_MSG_CANCEL; nfs_lockdmsg_dequeue(&msgreq); msg->lm_xid = nfs_lockxid_get(); nfs_lockdmsg_enqueue(&msgreq); msgreq.lmr_saved_errno = error; msgreq.lmr_errno = 0; msgreq.lmr_answered = 0; /* reset timeout */ timeo = 2*hz; /* send cancel request */ continue; } break; } /* * If the mount is hung and we've requested not to hang * on remote filesystems, then bail now. */ if ((p != NULL) && ((proc_noremotehang(p)) != 0) && ((nmp->nm_state & (NFSSTA_TIMEO|NFSSTA_LOCKTIMEO)) != 0)) { if (fl->l_type == F_UNLCK) printf("nfs_dolock: aborting unlock request " "due to timeout (noremotehang)\n"); error = EIO; break; } /* warn if we're not getting any response */ microuptime(&now); if ((msgreq.lmr_errno != EINPROGRESS) && (nmp->nm_tprintf_initial_delay != 0) && ((lastmsg + nmp->nm_tprintf_delay) < now.tv_sec)) { lastmsg = now.tv_sec; nfs_down(nmp, p, 0, NFSSTA_LOCKTIMEO, "lockd not responding"); wentdown = 1; } if (msgreq.lmr_errno == EINPROGRESS) { /* * We've got a blocked lock request that we are * going to retry. First, we'll want to try to * send a cancel for the previous request. * * Clear errno so if we don't get a response * to the resend we'll call nfs_down(). * Also reset timeout because we'll expect a * quick response to the cancel/resend (even if * it is NLM_BLOCKED). */ msg->lm_flags |= LOCKD_MSG_CANCEL; nfs_lockdmsg_dequeue(&msgreq); msg->lm_xid = nfs_lockxid_get(); nfs_lockdmsg_enqueue(&msgreq); msgreq.lmr_saved_errno = msgreq.lmr_errno; msgreq.lmr_errno = 0; msgreq.lmr_answered = 0; timeo = 2*hz; /* send cancel then resend request */ continue; } /* * We timed out, so we will rewrite the request * to the fifo, but only if it isn't already full. */ ioflg |= IO_NDELAY; timeo *= 2; if (timeo > 60*hz) timeo = 60*hz; /* resend request */ continue; } /* we got a reponse, so the server's lockd is OK */ nfs_up(VFSTONFS(vnode_mount(vp)), p, NFSSTA_LOCKTIMEO, wentdown ? "lockd alive again" : NULL); wentdown = 0; if (msgreq.lmr_errno == EINPROGRESS) { /* got NLM_BLOCKED response */ /* need to wait for NLM_GRANTED */ timeo = 60*hz; msgreq.lmr_answered = 0; goto wait_for_granted; } if ((msg->lm_flags & LOCKD_MSG_CANCEL) && (msgreq.lmr_saved_errno == EINPROGRESS)) { /* * We just got a successful reply to the * cancel of the previous blocked lock request. * Now, go ahead and resend the request. */ msg->lm_flags &= ~LOCKD_MSG_CANCEL; nfs_lockdmsg_dequeue(&msgreq); msg->lm_xid = nfs_lockxid_get(); nfs_lockdmsg_enqueue(&msgreq); msgreq.lmr_saved_errno = 0; msgreq.lmr_errno = 0; msgreq.lmr_answered = 0; timeo = 2*hz; /* resend request */ continue; } if ((msg->lm_flags & LOCKD_MSG_TEST) && msgreq.lmr_errno == 0) { if (msg->lm_fl.l_type != F_UNLCK) { fl->l_type = msg->lm_fl.l_type; fl->l_pid = msg->lm_fl.l_pid; fl->l_start = msg->lm_fl.l_start; fl->l_len = msg->lm_fl.l_len; fl->l_whence = SEEK_SET; } else { fl->l_type = F_UNLCK; } } /* * If the blocked lock request was cancelled. * Restore the error condition from when we * originally bailed on the request. */ if (msg->lm_flags & LOCKD_MSG_CANCEL) { msg->lm_flags &= ~LOCKD_MSG_CANCEL; error = msgreq.lmr_saved_errno; } else error = msgreq.lmr_errno; if (!error) { /* record that NFS file locking has worked on this mount */ nmp = VFSTONFS(vnode_mount(vp)); if (nmp && !(nmp->nm_state & NFSSTA_LOCKSWORK)) nmp->nm_state |= NFSSTA_LOCKSWORK; /* * If we successfully acquired a lock, make sure this pid * is in the nfs_lock_pid hash table so we know we can't * short-circuit unlock requests. */ if ((lockpidcheck == ENOENT) && ((ap->a_op == F_SETLK) || (ap->a_op == F_SETLKW))) nfs_lock_pid_check(p, 1, vp); } break; } nfs_lockdmsg_dequeue(&msgreq); error1 = VNOP_CLOSE(wvp, FWRITE, ap->a_context); vnode_rele(wvp); vnode_put(wvp); /* prefer any previous 'error' to our vn_close 'error1'. */ return (error != 0 ? error : error1); } /* * nfslockdans -- * NFS advisory byte-level locks answer from the lock daemon. */ int nfslockdans(proc_t p, struct lockd_ans *ansp) { LOCKD_MSG_REQUEST *msgreq; int error; /* Let root make this call. */ error = proc_suser(p); if (error) return (error); /* the version should match, or we're out of sync */ if (ansp->la_version != LOCKD_ANS_VERSION) return (EINVAL); /* try to find the lockd message by transaction id (cookie) */ msgreq = nfs_lockdmsg_find_by_xid(ansp->la_xid); if (ansp->la_flags & LOCKD_ANS_GRANTED) { /* * We can't depend on the granted message having our cookie, * so we check the answer against the lockd message found. * If no message was found or it doesn't match the answer, * we look for the lockd message by the answer's lock info. */ if (!msgreq || nfs_lockdmsg_compare_to_answer(msgreq, ansp)) msgreq = nfs_lockdmsg_find_by_answer(ansp); /* * We need to make sure this request isn't being cancelled * If it is, we don't want to accept the granted message. */ if (msgreq && (msgreq->lmr_msg.lm_flags & LOCKD_MSG_CANCEL)) msgreq = NULL; } if (!msgreq) return (EPIPE); msgreq->lmr_errno = ansp->la_errno; if ((msgreq->lmr_msg.lm_flags & LOCKD_MSG_TEST) && msgreq->lmr_errno == 0) { if (ansp->la_flags & LOCKD_ANS_LOCK_INFO) { if (ansp->la_flags & LOCKD_ANS_LOCK_EXCL) msgreq->lmr_msg.lm_fl.l_type = F_WRLCK; else msgreq->lmr_msg.lm_fl.l_type = F_RDLCK; msgreq->lmr_msg.lm_fl.l_pid = ansp->la_pid; msgreq->lmr_msg.lm_fl.l_start = ansp->la_start; msgreq->lmr_msg.lm_fl.l_len = ansp->la_len; } else { msgreq->lmr_msg.lm_fl.l_type = F_UNLCK; } } msgreq->lmr_answered = 1; (void)wakeup((void *)msgreq); return (0); } /* * nfslockdfd -- * NFS advisory byte-level locks: fifo file# from the lock daemon. */ int nfslockdfd(proc_t p, int fd) { int error; vnode_t vp, oldvp; error = proc_suser(p); if (error) return (error); if (fd < 0) { vp = NULL; } else { error = file_vnode(fd, &vp); if (error) return (error); error = vnode_getwithref(vp); if (error) return (error); error = vnode_ref(vp); if (error) { vnode_put(vp); return (error); } } oldvp = nfslockdvnode; nfslockdvnode = vp; if (oldvp) { vnode_rele(oldvp); } (void)wakeup((void *)&nfslockdvnode); if (vp) { vnode_put(vp); } return (0); } /* * nfslockdwait -- * lock daemon waiting for lock request */ int nfslockdwait(proc_t p) { int error; error = proc_suser(p); if (error) return (error); if (nfslockdwaiting || nfslockdvnode) return (EBUSY); nfslockdstarttimeout = 0; nfslockdwaiting = 1; tsleep((void *)&nfslockdwaiting, PCATCH | PUSER, "lockd", 0); nfslockdwaiting = 0; return (0); }