From f0669d6c9e71dffa3f4104a202e3e1046c64021c Mon Sep 17 00:00:00 2001 From: alfred Date: Tue, 17 Apr 2001 20:45:23 +0000 Subject: Implement client side NFS locks. Obtained from: BSD/os Import Ok'd by: mckusick, jkh, motd on builder.freebsd.org --- sys/nfs/nfs.h | 1 + sys/nfs/nfs_lock.c | 269 +++++++++++++++++++++++++++++++++++++++++++++++++ sys/nfs/nfs_lock.h | 112 ++++++++++++++++++++ sys/nfs/nfs_syscalls.c | 9 ++ sys/nfs/nfs_vnops.c | 9 +- sys/nfs/nlminfo.h | 45 +++++++++ 6 files changed, 438 insertions(+), 7 deletions(-) create mode 100644 sys/nfs/nfs_lock.c create mode 100644 sys/nfs/nfs_lock.h create mode 100644 sys/nfs/nlminfo.h (limited to 'sys/nfs') diff --git a/sys/nfs/nfs.h b/sys/nfs/nfs.h index 259ec20..2b0f664 100644 --- a/sys/nfs/nfs.h +++ b/sys/nfs/nfs.h @@ -274,6 +274,7 @@ struct nfsstats { #define NFSSVC_GOTAUTH 0x040 #define NFSSVC_AUTHINFAIL 0x080 #define NFSSVC_MNTD 0x100 +#define NFSSVC_LOCKDANS 0x200 /* * fs.nfs sysctl(3) identifiers diff --git a/sys/nfs/nfs_lock.c b/sys/nfs/nfs_lock.c new file mode 100644 index 0000000..aaac361 --- /dev/null +++ b/sys/nfs/nfs_lock.c @@ -0,0 +1,269 @@ +/*- + * 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 + * $FreeBSD$ + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include /* for hz */ +#include /* for hz */ + +#include + +#include +#include +#include +#include +#include +#include +#include + +#define NFSOWNER_1ST_LEVEL_START 1 /* initial entries */ +#define NFSOWNER_2ND_LEVEL 256 /* some power of 2 */ + +#define NFSOWNER(tbl, i) \ + (tbl)[(i) / NFSOWNER_2ND_LEVEL][(i) % NFSOWNER_2ND_LEVEL] + +/* + * XXX + * We have to let the process know if the call succeeded. I'm using an extra + * field in the p_nlminfo field in the proc structure, as it is already for + * lockd stuff. + */ + +/* + * nfs_advlock -- + * NFS advisory byte-level locks. + */ +int +nfs_dolock(ap) + struct vop_advlock_args /* { + struct vnode *a_vp; + caddr_t a_id; + int a_op; + struct flock *a_fl; + int a_flags; + } */ *ap; +{ + LOCKD_MSG msg; + struct nameidata nd; + struct proc *p; + uid_t saved_uid; + struct vnode *vp, *wvp; + int error, error1; + struct flock *fl; + int fmode, ioflg; + + p = curproc; + vp = ap->a_vp; + fl = ap->a_fl; + + /* + * the NLM protocol doesn't allow the server to return an error + * on ranges, so we do it. Note that we should be returning + * EOVERFLOW in some cases, but we don't have it. + */ + if (fl->l_start < 0 || fl->l_len < 0 || + ((fl->l_len != 0 && + (fl->l_start + fl->l_len - 1) < 0))) + return (EINVAL); + + /* + * Fill in the information structure. + */ + msg.lm_version = LOCKD_MSG_VERSION; + msg.lm_msg_ident.pid = p->p_pid; + /* + * if there is no nfsowner table yet, allocate one. + */ + if (p->p_nlminfo == NULL) { + MALLOC(p->p_nlminfo, struct nlminfo *, + sizeof(struct nlminfo), M_LOCKF, M_WAITOK | M_ZERO); + p->p_nlminfo->pid_start = p->p_stats->p_start; + } + msg.lm_msg_ident.pid_start = p->p_nlminfo->pid_start; + msg.lm_msg_ident.msg_seq = ++(p->p_nlminfo->msg_seq); + + msg.lm_fl = *fl; + msg.lm_wait = ap->a_flags & F_WAIT; + msg.lm_getlk = ap->a_op == F_GETLK; + /* + * XXX -- I think this is wrong for anything other AF_INET. + */ + msg.lm_addr = *(VFSTONFS(vp->v_mount)->nm_nam); + 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); + msg.lm_nfsv3 = NFS_ISV3(vp); + msg.lm_cred = *(p->p_ucred); + + /* + * Open the lock fifo. If for any reason we don't find the fifo, it + * means that the lock daemon isn't running. Translate any missing + * file error message for the user, otherwise the application will + * complain that the user's file is missing, which isn't the case. + * Note that we use proc0's cred, so the fifo is opened as root. + */ + NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, _PATH_LCKFIFO, p); + + /* + * XXX Hack to temporarily allow this process (regardless of it's creds) + * to open the fifo we need to write to. vn_open() really should + * take a ucred (and once it does, this code should be fixed to use + * proc0's ucred. + */ + saved_uid = p->p_ucred->cr_uid; + p->p_ucred->cr_uid = 0; /* temporarly run the vn_open as root */ + + fmode = FFLAGS(O_WRONLY); + error = vn_open(&nd, &fmode, 0); + p->p_ucred->cr_uid = saved_uid; + if (error != 0) { + return (error == ENOENT ? EOPNOTSUPP : error); + } + wvp = nd.ni_vp; + VOP_UNLOCK(wvp, 0, p); /* vn_open leaves it locked */ + + + ioflg = IO_UNIT; + for (;;) { + VOP_LEASE(wvp, p, proc0.p_ucred, LEASE_WRITE); + + error = vn_rdwr(UIO_WRITE, wvp, (caddr_t)&msg, sizeof(msg), 0, + UIO_SYSSPACE, ioflg, proc0.p_ucred, NULL, p); + + if (error && (((ioflg & IO_NDELAY) == 0) || error != EAGAIN)) { + break; + } + /* + * If we're locking a file, wait for an answer. Unlocks succeed + * immediately. + */ + if (fl->l_type == F_UNLCK) + /* + * XXX this isn't exactly correct. The client side + * needs to continue sending it's unlock until + * it gets a responce back. + */ + break; + + /* + * retry after 20 seconds if we haven't gotten a responce yet. + * This number was picked out of thin air... but is longer + * then even a reasonably loaded system should take (at least + * on a local network). XXX Probably should use a back-off + * scheme. + */ + if ((error = tsleep((void *)p->p_nlminfo, + PCATCH | PUSER, "lockd", 20*hz)) != 0) { + if (error == EWOULDBLOCK) { + /* + * We timed out, so we rewrite the request + * to the fifo, but only if it isn't already + * full. + */ + ioflg |= IO_NDELAY; + continue; + } + + break; + } + + if (msg.lm_getlk && p->p_nlminfo->retcode == 0) { + if (p->p_nlminfo->set_getlk_pid) { + fl->l_pid = p->p_nlminfo->getlk_pid; + } else { + fl->l_type = F_UNLCK; + } + } + error = p->p_nlminfo->retcode; + break; + } + + if ((error1 = vn_close(wvp, FWRITE, proc0.p_ucred, p)) && error == 0) + return (error1); + + return (error); +} + +/* + * nfslockdans -- + * NFS advisory byte-level locks answer from the lock daemon. + */ +int +nfslockdans(p, ansp) + struct proc *p; + struct lockd_ans *ansp; +{ + int error; + + /* Let root, or someone who once was root (lockd generally + * switches to the daemon uid once it is done setting up) make + * this call + */ + if ((error = suser(p)) != 0 && p->p_cred->p_svuid != 0) + return (error); + + /* the version should match, or we're out of sync */ + if (ansp->la_vers != LOCKD_ANS_VERSION) + return (EINVAL); + + /* Find the process, set its return errno and wake it up. */ + if ((p = pfind(ansp->la_msg_ident.pid)) == NULL) + return (ESRCH); + + /* verify the pid hasn't been reused (if we can), and it isn't waiting + * for an answer from a more recent request. We return an EPIPE if + * the match fails, because we've already used ESRCH above, and this + * is sort of like writing on a pipe after the reader has closed it. + */ + if (p->p_nlminfo == NULL || + ((ansp->la_msg_ident.msg_seq != -1) && + (timevalcmp(&p->p_nlminfo->pid_start, + &ansp->la_msg_ident.pid_start, !=) || + p->p_nlminfo->msg_seq != ansp->la_msg_ident.msg_seq))) + return (EPIPE); + + p->p_nlminfo->retcode = ansp->la_errno; + p->p_nlminfo->set_getlk_pid = ansp->la_set_getlk_pid; + p->p_nlminfo->getlk_pid = ansp->la_getlk_pid; + + (void)wakeup((void *)p->p_nlminfo); + + return (0); +} diff --git a/sys/nfs/nfs_lock.h b/sys/nfs/nfs_lock.h new file mode 100644 index 0000000..64b6c70 --- /dev/null +++ b/sys/nfs/nfs_lock.h @@ -0,0 +1,112 @@ +/*- + * Copyright (c) 1998 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 nfs_lock.h,v 2.2 1998/04/28 19:38:41 don Exp + * $FreeBSD$ + */ + +/* + * lockd uses the nfssvc system call to get the unique kernel services it needs. + * It passes in a request structure with a version number at the start. + * This prevents libc from needing to change if the information passed + * between lockd and the kernel needs to change. + * + * If a structure changes, you must bump the version number. + */ + +#include + + +#define LOCKD_REQ_VERSION 1 + +struct lockd_req { + int vers; /* keep in sync with kernel please */ + int op; /* F_GETLK | F_SETLK | F_UNLCK */ + int owner; /* owner of lock, -1 to allocate one */ + int owner_rel_ok; /* release owner if no locks left ? */ + int *owner_ret; /* owner alloc/free result target */ + void *fh; /* NFS file handle */ + size_t fh_len; /* NFS file handle length */ + u_quad_t offset; /* offset of where to start lock */ + u_quad_t len; /* length of range to lock */ + int type; /* F_RDLCK | F_WRLCK | F_UNLCK */ + struct ucred cred; /* user credentials to use for lock */ + struct sockaddr saddr; /* XXX how about non AF_INET ?? */ + int pid; /* pid of lock requester */ +}; + +/* + * The fifo where the kernel writes requests for locks on remote NFS files, + * and where lockd reads these requests. + * + */ +#define _PATH_LCKFIFO "/var/run/lock" + +/* + * This structure is used to uniquely identify the process which originated + * a particular message to lockd. A sequence number is used to differentiate + * multiple messages from the same process. A process start time is used to + * detect the unlikely, but possible, event of the recycling of a pid. + */ +struct lockd_msg_ident { + pid_t pid; /* The process ID. */ + struct timeval pid_start; /* Start time of process id */ + int msg_seq; /* Sequence number of message */ +}; + +#define LOCKD_MSG_VERSION 1 + +/* + * The structure that the kernel hands us for each lock request. + */ +typedef struct __lock_msg { + int lm_version; /* which version is this */ + struct lockd_msg_ident lm_msg_ident; /* originator of the message */ + struct flock lm_fl; /* The lock request. */ + int lm_wait; /* The F_WAIT flag. */ + int lm_getlk; /* is this a F_GETLK request */ + struct sockaddr lm_addr; /* The address. */ + int lm_nfsv3; /* If NFS version 3. */ + size_t lm_fh_len; /* The file handle length. */ + struct ucred lm_cred; /* user cred for lock req */ + u_int8_t lm_fh[NFS_SMALLFH];/* The file handle. */ +} LOCKD_MSG; + +#define LOCKD_ANS_VERSION 1 + +struct lockd_ans { + int la_vers; + struct lockd_msg_ident la_msg_ident; /* originator of the message */ + int la_errno; + int la_set_getlk_pid; /* use returned pid */ + int la_getlk_pid; /* returned pid for F_GETLK */ +}; + +#ifdef _KERNEL +int nfs_dolock(struct vop_advlock_args *ap); +int nfslockdans(struct proc *p, struct lockd_ans *ansp); +int nfslockdreq(struct proc *p, struct lockd_req *reqp); +#endif diff --git a/sys/nfs/nfs_syscalls.c b/sys/nfs/nfs_syscalls.c index 2d46568..a47d5a8 100644 --- a/sys/nfs/nfs_syscalls.c +++ b/sys/nfs/nfs_syscalls.c @@ -56,6 +56,8 @@ #include #include #include +#include +#include #include #include @@ -69,6 +71,7 @@ #include #include #include +#include static MALLOC_DEFINE(M_NFSSVC, "NFS srvsock", "Nfs server structure"); @@ -152,6 +155,12 @@ nfssvc(p, uap) #endif /* NFS_NOSERVER */ int error; + if ((uap->flag & NFSSVC_LOCKDANS) != 0) { + struct lockd_ans la; + + error = copyin(uap->argp, &la, sizeof(la)); + return (error != 0 ? error : nfslockdans(p, &la)); + } /* * Must be super user */ diff --git a/sys/nfs/nfs_vnops.c b/sys/nfs/nfs_vnops.c index 2a5564e..b37f6da 100644 --- a/sys/nfs/nfs_vnops.c +++ b/sys/nfs/nfs_vnops.c @@ -76,6 +76,7 @@ #include #include #include +#include #include #include @@ -3057,14 +3058,8 @@ nfs_advlock(ap) int a_flags; } */ *ap; { - register struct nfsnode *np = VTONFS(ap->a_vp); - /* - * The following kludge is to allow diskless support to work - * until a real NFS lockd is implemented. Basically, just pretend - * that this is a local lock. - */ - return (lf_advlock(ap, &(np->n_lockf), np->n_size)); + return (nfs_dolock(ap)); } /* diff --git a/sys/nfs/nlminfo.h b/sys/nfs/nlminfo.h new file mode 100644 index 0000000..79c6e17 --- /dev/null +++ b/sys/nfs/nlminfo.h @@ -0,0 +1,45 @@ +/*- + * Copyright (c) 1998 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 nlminfo.h,v 2.1 1998/03/18 01:30:38 don Exp + * $FreeBSD$ + */ + +/* + * Misc NLM informationi, some needed for the master lockd process, and some + * needed by every process doing nlm based locking. + */ +struct nlminfo { + /* these are used by any process doing nlm locking */ + int msg_seq; /* sequence counter for lock requests */ + int retcode; /* return code for lock requests */ + int set_getlk_pid; + int getlk_pid; + struct timeval pid_start; /* process starting time */ +}; + +extern void nlminfo_release __P((struct proc *p)); + -- cgit v1.1