175631Salfred/*- 275631Salfred * Copyright (c) 1997 Berkeley Software Design, Inc. All rights reserved. 375631Salfred * 475631Salfred * Redistribution and use in source and binary forms, with or without 575631Salfred * modification, are permitted provided that the following conditions 675631Salfred * are met: 775631Salfred * 1. Redistributions of source code must retain the above copyright 875631Salfred * notice, this list of conditions and the following disclaimer. 975631Salfred * 2. Redistributions in binary form must reproduce the above copyright 1075631Salfred * notice, this list of conditions and the following disclaimer in the 1175631Salfred * documentation and/or other materials provided with the distribution. 1275631Salfred * 3. Berkeley Software Design Inc's name may not be used to endorse or 1375631Salfred * promote products derived from this software without specific prior 1475631Salfred * written permission. 1575631Salfred * 1675631Salfred * THIS SOFTWARE IS PROVIDED BY BERKELEY SOFTWARE DESIGN INC ``AS IS'' AND 1775631Salfred * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 1875631Salfred * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 1975631Salfred * ARE DISCLAIMED. IN NO EVENT SHALL BERKELEY SOFTWARE DESIGN INC BE LIABLE 2075631Salfred * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 2175631Salfred * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 2275631Salfred * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 2375631Salfred * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 2475631Salfred * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 2575631Salfred * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 2675631Salfred * SUCH DAMAGE. 2775631Salfred * 2875631Salfred * from BSDI nfs_lock.c,v 2.4 1998/12/14 23:49:56 jch Exp 2975631Salfred */ 3075631Salfred 3183651Speter#include <sys/cdefs.h> 3283651Speter__FBSDID("$FreeBSD$"); 3383651Speter 3475631Salfred#include <sys/param.h> 3575631Salfred#include <sys/systm.h> 36138430Sphk#include <sys/conf.h> 3775631Salfred#include <sys/fcntl.h> 3876166Smarkm#include <sys/kernel.h> /* for hz */ 39114216Skan#include <sys/limits.h> 4076166Smarkm#include <sys/lock.h> 4175631Salfred#include <sys/malloc.h> 4276166Smarkm#include <sys/lockf.h> /* for hz */ /* Must come after sys/malloc.h */ 4375631Salfred#include <sys/mbuf.h> 4475631Salfred#include <sys/mount.h> 4575631Salfred#include <sys/namei.h> 46168931Srwatson#include <sys/priv.h> 4775631Salfred#include <sys/proc.h> 4876166Smarkm#include <sys/resourcevar.h> 4975631Salfred#include <sys/socket.h> 5076166Smarkm#include <sys/socket.h> 5175631Salfred#include <sys/unistd.h> 5275631Salfred#include <sys/vnode.h> 5375631Salfred 5475631Salfred#include <net/if.h> 5575631Salfred 5675631Salfred#include <nfs/nfsproto.h> 57210455Srmacklem#include <nfs/nfs_lock.h> 5883651Speter#include <nfsclient/nfs.h> 5983651Speter#include <nfsclient/nfsmount.h> 6083651Speter#include <nfsclient/nfsnode.h> 6183651Speter#include <nfsclient/nlminfo.h> 6275631Salfred 63151695Sglebiusextern void (*nlminfo_release_p)(struct proc *p); 64151695Sglebius 65214048Srmacklemvop_advlock_t *nfs_advlock_p = nfs_dolock; 66214048Srmacklemvop_reclaim_t *nfs_reclaim_p = NULL; 67214048Srmacklem 68227293Sedstatic MALLOC_DEFINE(M_NFSLOCK, "nfsclient_lock", "NFS lock request"); 69227293Sedstatic MALLOC_DEFINE(M_NLMINFO, "nfsclient_nlminfo", 70227293Sed "NFS lock process structure"); 71138430Sphk 72138430Sphkstatic int nfslockdans(struct thread *td, struct lockd_ans *ansp); 73151695Sglebiusstatic void nlminfo_release(struct proc *p); 7475631Salfred/* 75138430Sphk * -------------------------------------------------------------------- 76138430Sphk * A miniature device driver which the userland uses to talk to us. 77138430Sphk * 78138430Sphk */ 79138430Sphk 80138430Sphkstatic struct cdev *nfslock_dev; 81138430Sphkstatic struct mtx nfslock_mtx; 82138430Sphkstatic int nfslock_isopen; 83138430Sphkstatic TAILQ_HEAD(,__lock_msg) nfslock_list; 84138430Sphk 85138430Sphkstatic int 86138430Sphknfslock_open(struct cdev *dev, int oflags, int devtype, struct thread *td) 87138430Sphk{ 88138430Sphk int error; 89138430Sphk 90168931Srwatson error = priv_check(td, PRIV_NFS_LOCKD); 91168931Srwatson if (error) 92168931Srwatson return (error); 93168931Srwatson 94138430Sphk mtx_lock(&nfslock_mtx); 95138430Sphk if (!nfslock_isopen) { 96138430Sphk error = 0; 97138430Sphk nfslock_isopen = 1; 98138430Sphk } else { 99138430Sphk error = EOPNOTSUPP; 100138430Sphk } 101138430Sphk mtx_unlock(&nfslock_mtx); 102138430Sphk 103138430Sphk return (error); 104138430Sphk} 105138430Sphk 106138430Sphkstatic int 107138430Sphknfslock_close(struct cdev *dev, int fflag, int devtype, struct thread *td) 108138430Sphk{ 109138430Sphk struct __lock_msg *lm; 110138430Sphk 111138430Sphk mtx_lock(&nfslock_mtx); 112138430Sphk nfslock_isopen = 0; 113138430Sphk while (!TAILQ_EMPTY(&nfslock_list)) { 114138430Sphk lm = TAILQ_FIRST(&nfslock_list); 115138430Sphk /* XXX: answer request */ 116138430Sphk TAILQ_REMOVE(&nfslock_list, lm, lm_link); 117138430Sphk free(lm, M_NFSLOCK); 118138430Sphk } 119138430Sphk mtx_unlock(&nfslock_mtx); 120138430Sphk return (0); 121138430Sphk} 122138430Sphk 123138430Sphkstatic int 124138430Sphknfslock_read(struct cdev *dev, struct uio *uio, int ioflag) 125138430Sphk{ 126138430Sphk int error; 127138430Sphk struct __lock_msg *lm; 128138430Sphk 129138430Sphk if (uio->uio_resid != sizeof *lm) 130138430Sphk return (EOPNOTSUPP); 131138430Sphk lm = NULL; 132138430Sphk error = 0; 133138430Sphk mtx_lock(&nfslock_mtx); 134138430Sphk while (TAILQ_EMPTY(&nfslock_list)) { 135138430Sphk error = msleep(&nfslock_list, &nfslock_mtx, PSOCK | PCATCH, 136138430Sphk "nfslockd", 0); 137138430Sphk if (error) 138138430Sphk break; 139138430Sphk } 140138430Sphk if (!error) { 141138430Sphk lm = TAILQ_FIRST(&nfslock_list); 142138430Sphk TAILQ_REMOVE(&nfslock_list, lm, lm_link); 143138430Sphk } 144138430Sphk mtx_unlock(&nfslock_mtx); 145138430Sphk if (!error) { 146138430Sphk error = uiomove(lm, sizeof *lm, uio); 147138430Sphk free(lm, M_NFSLOCK); 148138430Sphk } 149138430Sphk return (error); 150138430Sphk} 151138430Sphk 152138430Sphkstatic int 153138430Sphknfslock_write(struct cdev *dev, struct uio *uio, int ioflag) 154138430Sphk{ 155138430Sphk struct lockd_ans la; 156138430Sphk int error; 157138430Sphk 158138430Sphk if (uio->uio_resid != sizeof la) 159138430Sphk return (EOPNOTSUPP); 160138430Sphk error = uiomove(&la, sizeof la, uio); 161138430Sphk if (!error) 162138430Sphk error = nfslockdans(curthread, &la); 163138430Sphk return (error); 164138430Sphk} 165138430Sphk 166138430Sphkstatic int 167138430Sphknfslock_send(struct __lock_msg *lm) 168138430Sphk{ 169138430Sphk struct __lock_msg *lm2; 170138430Sphk int error; 171138430Sphk 172138430Sphk error = 0; 173138430Sphk lm2 = malloc(sizeof *lm2, M_NFSLOCK, M_WAITOK); 174138430Sphk mtx_lock(&nfslock_mtx); 175138430Sphk if (nfslock_isopen) { 176138430Sphk memcpy(lm2, lm, sizeof *lm2); 177138430Sphk TAILQ_INSERT_TAIL(&nfslock_list, lm2, lm_link); 178138430Sphk wakeup(&nfslock_list); 179138430Sphk } else { 180138430Sphk error = EOPNOTSUPP; 181138430Sphk } 182138430Sphk mtx_unlock(&nfslock_mtx); 183138430Sphk if (error) 184138430Sphk free(lm2, M_NFSLOCK); 185138430Sphk return (error); 186138430Sphk} 187138430Sphk 188138430Sphkstatic struct cdevsw nfslock_cdevsw = { 189138430Sphk .d_version = D_VERSION, 190138430Sphk .d_open = nfslock_open, 191138430Sphk .d_close = nfslock_close, 192138430Sphk .d_read = nfslock_read, 193138430Sphk .d_write = nfslock_write, 194138430Sphk .d_name = "nfslock" 195138430Sphk}; 196138430Sphk 197138430Sphkstatic int 198138430Sphknfslock_modevent(module_t mod __unused, int type, void *data __unused) 199138430Sphk{ 200138430Sphk 201138430Sphk switch (type) { 202138430Sphk case MOD_LOAD: 203138430Sphk if (bootverbose) 204138430Sphk printf("nfslock: pseudo-device\n"); 205138430Sphk mtx_init(&nfslock_mtx, "nfslock", NULL, MTX_DEF); 206138430Sphk TAILQ_INIT(&nfslock_list); 207151695Sglebius nlminfo_release_p = nlminfo_release; 208138430Sphk nfslock_dev = make_dev(&nfslock_cdevsw, 0, 209138430Sphk UID_ROOT, GID_KMEM, 0600, _PATH_NFSLCKDEV); 210138430Sphk return (0); 211138430Sphk default: 212138430Sphk return (EOPNOTSUPP); 213138430Sphk } 214138430Sphk} 215138430Sphk 216138430SphkDEV_MODULE(nfslock, nfslock_modevent, NULL); 217138430SphkMODULE_VERSION(nfslock, 1); 218138430Sphk 219138430Sphk 220138430Sphk/* 22175631Salfred * XXX 22275631Salfred * We have to let the process know if the call succeeded. I'm using an extra 22383651Speter * field in the p_nlminfo field in the proc structure, as it is already for 22475631Salfred * lockd stuff. 22575631Salfred */ 22675631Salfred 22775631Salfred/* 22875631Salfred * nfs_advlock -- 22975631Salfred * NFS advisory byte-level locks. 230178243Skib * 231178243Skib * The vnode shall be (shared) locked on the entry, it is 232178243Skib * unconditionally unlocked after. 23375631Salfred */ 23475631Salfredint 23583651Speternfs_dolock(struct vop_advlock_args *ap) 23675631Salfred{ 23775631Salfred LOCKD_MSG msg; 23883366Sjulian struct thread *td; 239138430Sphk struct vnode *vp; 240138430Sphk int error; 24175631Salfred struct flock *fl; 24283366Sjulian struct proc *p; 243214048Srmacklem struct nfsmount *nmp; 24475631Salfred 24583366Sjulian td = curthread; 24683366Sjulian p = td->td_proc; 24783366Sjulian 24875631Salfred vp = ap->a_vp; 24975631Salfred fl = ap->a_fl; 250214048Srmacklem nmp = VFSTONFS(vp->v_mount); 25175631Salfred 252178243Skib ASSERT_VOP_LOCKED(vp, "nfs_dolock"); 253178243Skib 254214048Srmacklem nmp->nm_getinfo(vp, msg.lm_fh, &msg.lm_fh_len, &msg.lm_addr, 255216931Srmacklem &msg.lm_nfsv3, NULL, NULL); 256178243Skib VOP_UNLOCK(vp, 0); 257178243Skib 25875631Salfred /* 25975631Salfred * the NLM protocol doesn't allow the server to return an error 26082174Sache * on ranges, so we do it. 26175631Salfred */ 26282194Sache if (fl->l_whence != SEEK_END) { 26382213Sache if ((fl->l_whence != SEEK_CUR && fl->l_whence != SEEK_SET) || 26482204Sache fl->l_start < 0 || 26582204Sache (fl->l_len < 0 && 26682204Sache (fl->l_start == 0 || fl->l_start + fl->l_len < 0))) 26782194Sache return (EINVAL); 26882204Sache if (fl->l_len > 0 && 26982204Sache (fl->l_len - 1 > OFF_MAX - fl->l_start)) 27082194Sache return (EOVERFLOW); 27182194Sache } 27275631Salfred 27375631Salfred /* 27475631Salfred * Fill in the information structure. 27575631Salfred */ 27675631Salfred msg.lm_version = LOCKD_MSG_VERSION; 27775631Salfred msg.lm_msg_ident.pid = p->p_pid; 278178243Skib 279178243Skib mtx_lock(&Giant); 28075631Salfred /* 28175631Salfred * if there is no nfsowner table yet, allocate one. 28275631Salfred */ 28375631Salfred if (p->p_nlminfo == NULL) { 284184214Sdes p->p_nlminfo = malloc(sizeof(struct nlminfo), 285184214Sdes M_NLMINFO, M_WAITOK | M_ZERO); 28675631Salfred p->p_nlminfo->pid_start = p->p_stats->p_start; 287114434Sdes timevaladd(&p->p_nlminfo->pid_start, &boottime); 28875631Salfred } 28975631Salfred msg.lm_msg_ident.pid_start = p->p_nlminfo->pid_start; 29075631Salfred msg.lm_msg_ident.msg_seq = ++(p->p_nlminfo->msg_seq); 29175631Salfred 29275631Salfred msg.lm_fl = *fl; 29375631Salfred msg.lm_wait = ap->a_flags & F_WAIT; 29475631Salfred msg.lm_getlk = ap->a_op == F_GETLK; 295101947Salfred cru2x(td->td_ucred, &msg.lm_cred); 29675631Salfred 29775631Salfred for (;;) { 298138430Sphk error = nfslock_send(&msg); 299138430Sphk if (error) 300178243Skib goto out; 30175631Salfred 302138430Sphk /* Unlocks succeed immediately. */ 30375631Salfred if (fl->l_type == F_UNLCK) 304178243Skib goto out; 30575631Salfred 30675631Salfred /* 307161371Sthomas * Retry after 20 seconds if we haven't gotten a response yet. 30875631Salfred * This number was picked out of thin air... but is longer 30975631Salfred * then even a reasonably loaded system should take (at least 31083651Speter * on a local network). XXX Probably should use a back-off 31175631Salfred * scheme. 312116185Srwatson * 313116185Srwatson * XXX: No PCATCH here since we currently have no useful 314116185Srwatson * way to signal to the userland rpc.lockd that the request 315116185Srwatson * has been aborted. Once the rpc.lockd implementation 316116185Srwatson * can handle aborts, and we report them properly, 317116185Srwatson * PCATCH can be put back. In the mean time, if we did 318116185Srwatson * permit aborting, the lock attempt would "get lost" 319116185Srwatson * and the lock would get stuck in the locked state. 32075631Salfred */ 321115415Srwatson error = tsleep(p->p_nlminfo, PUSER, "lockd", 20*hz); 322107104Salfred if (error != 0) { 32375631Salfred if (error == EWOULDBLOCK) { 32475631Salfred /* 32575631Salfred * We timed out, so we rewrite the request 326154316Srwatson * to the fifo. 32775631Salfred */ 32875631Salfred continue; 32975631Salfred } 33075631Salfred 33175631Salfred break; 33275631Salfred } 33375631Salfred 33475631Salfred if (msg.lm_getlk && p->p_nlminfo->retcode == 0) { 33575631Salfred if (p->p_nlminfo->set_getlk_pid) { 336177633Sdfr fl->l_sysid = 0; /* XXX */ 33775631Salfred fl->l_pid = p->p_nlminfo->getlk_pid; 33875631Salfred } else { 33975631Salfred fl->l_type = F_UNLCK; 34075631Salfred } 34175631Salfred } 34275631Salfred error = p->p_nlminfo->retcode; 34375631Salfred break; 34475631Salfred } 345178243Skib out: 346178243Skib mtx_unlock(&Giant); 347138430Sphk return (error); 34875631Salfred} 34975631Salfred 35075631Salfred/* 35175631Salfred * nfslockdans -- 35275631Salfred * NFS advisory byte-level locks answer from the lock daemon. 35375631Salfred */ 354138430Sphkstatic int 35586363Srwatsonnfslockdans(struct thread *td, struct lockd_ans *ansp) 35675631Salfred{ 35786363Srwatson struct proc *targetp; 35875631Salfred 35975631Salfred /* the version should match, or we're out of sync */ 36075631Salfred if (ansp->la_vers != LOCKD_ANS_VERSION) 36175631Salfred return (EINVAL); 36275631Salfred 36375631Salfred /* Find the process, set its return errno and wake it up. */ 36486363Srwatson if ((targetp = pfind(ansp->la_msg_ident.pid)) == NULL) 36575631Salfred return (ESRCH); 36675631Salfred 36783651Speter /* verify the pid hasn't been reused (if we can), and it isn't waiting 36875631Salfred * for an answer from a more recent request. We return an EPIPE if 36975631Salfred * the match fails, because we've already used ESRCH above, and this 37075631Salfred * is sort of like writing on a pipe after the reader has closed it. 37175631Salfred */ 37286363Srwatson if (targetp->p_nlminfo == NULL || 37375631Salfred ((ansp->la_msg_ident.msg_seq != -1) && 37486363Srwatson (timevalcmp(&targetp->p_nlminfo->pid_start, 37575631Salfred &ansp->la_msg_ident.pid_start, !=) || 37686363Srwatson targetp->p_nlminfo->msg_seq != ansp->la_msg_ident.msg_seq))) { 37786363Srwatson PROC_UNLOCK(targetp); 37875631Salfred return (EPIPE); 37977563Sjake } 38075631Salfred 38186363Srwatson targetp->p_nlminfo->retcode = ansp->la_errno; 38286363Srwatson targetp->p_nlminfo->set_getlk_pid = ansp->la_set_getlk_pid; 38386363Srwatson targetp->p_nlminfo->getlk_pid = ansp->la_getlk_pid; 38475631Salfred 385107104Salfred wakeup(targetp->p_nlminfo); 38675631Salfred 38786363Srwatson PROC_UNLOCK(targetp); 38875631Salfred return (0); 38975631Salfred} 390138430Sphk 391151695Sglebius/* 392151695Sglebius * Free nlminfo attached to process. 393151695Sglebius */ 394151695Sglebiusvoid 395151695Sglebiusnlminfo_release(struct proc *p) 396151695Sglebius{ 397151695Sglebius free(p->p_nlminfo, M_NLMINFO); 398151695Sglebius p->p_nlminfo = NULL; 399151695Sglebius} 400