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freebsd-skq/sys/nfsclient/nfs_subs.c
John Baldwin 5aefb4cbbf Close a race in NFS lookup processing that could result in stale name cache 
entries on one client when a directory was renamed on another client.  The
root cause for the stale entry being trusted is that each per-vnode nfsnode
structure has a single 'n_ctime' timestamp used to validate positive name
cache entries.  However, if there are multiple entries for a single vnode,
they all share a single timestamp.  To fix this, extend the name cache
to allow filesystems to optionally store a timestamp value in each name
cache entry.  The NFS clients now fetch the timestamp associated with
each name cache entry and use that to validate cache hits instead of the
timestamps previously stored in the nfsnode.  Another part of the fix is
that the NFS clients now use timestamps from the post-op attributes of
RPCs when adding name cache entries rather than pulling the timestamps out
of the file's attribute cache.  The latter is subject to races with other
lookups updating the attribute cache concurrently.  Some more details:
- Add a variant of nfsm_postop_attr() to the old NFS client that can return
  a vattr structure with a copy of the post-op attributes.
- Handle lookups of "." as a special case in the NFS clients since the name
  cache does not store name cache entries for ".", so we cannot get a
  useful timestamp.  It didn't really make much sense to recheck the
  attributes on the the directory to validate the namecache hit for "."
  anyway.
- ABI compat shims for the name cache routines are present in this commit
  so that it is safe to MFC.

MFC after:	2 weeks
2012-01-20 20:02:01 +00:00

1148 lines
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/*-
* Copyright (c) 1989, 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Rick Macklem at The University of Guelph.
*
* 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.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
*
* @(#)nfs_subs.c 8.8 (Berkeley) 5/22/95
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
/*
* These functions support the macros and help fiddle mbuf chains for
* the nfs op functions. They do things like create the rpc header and
* copy data between mbuf chains and uio lists.
*/
#include "opt_kdtrace.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/bio.h>
#include <sys/buf.h>
#include <sys/proc.h>
#include <sys/mount.h>
#include <sys/vnode.h>
#include <sys/namei.h>
#include <sys/mbuf.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <sys/malloc.h>
#include <sys/sysent.h>
#include <sys/syscall.h>
#include <sys/sysproto.h>
#include <sys/taskqueue.h>
#include <vm/vm.h>
#include <vm/vm_object.h>
#include <vm/vm_extern.h>
#include <vm/uma.h>
#include <nfs/nfsproto.h>
#include <nfsclient/nfs.h>
#include <nfsclient/nfsnode.h>
#include <nfs/nfs_kdtrace.h>
#include <nfs/xdr_subs.h>
#include <nfsclient/nfsm_subs.h>
#include <nfsclient/nfsmount.h>
#include <netinet/in.h>
/*
* Note that stdarg.h and the ANSI style va_start macro is used for both
* ANSI and traditional C compilers.
*/
#include <machine/stdarg.h>
#ifdef KDTRACE_HOOKS
dtrace_nfsclient_attrcache_flush_probe_func_t
dtrace_nfsclient_attrcache_flush_done_probe;
uint32_t nfsclient_attrcache_flush_done_id;
dtrace_nfsclient_attrcache_get_hit_probe_func_t
dtrace_nfsclient_attrcache_get_hit_probe;
uint32_t nfsclient_attrcache_get_hit_id;
dtrace_nfsclient_attrcache_get_miss_probe_func_t
dtrace_nfsclient_attrcache_get_miss_probe;
uint32_t nfsclient_attrcache_get_miss_id;
dtrace_nfsclient_attrcache_load_probe_func_t
dtrace_nfsclient_attrcache_load_done_probe;
uint32_t nfsclient_attrcache_load_done_id;
#endif /* !KDTRACE_HOOKS */
/*
* Data items converted to xdr at startup, since they are constant
* This is kinda hokey, but may save a little time doing byte swaps
*/
u_int32_t nfs_xdrneg1;
u_int32_t nfs_true, nfs_false;
/* And other global data */
static u_int32_t nfs_xid = 0;
static enum vtype nv2tov_type[8]= {
VNON, VREG, VDIR, VBLK, VCHR, VLNK, VNON, VNON
};
int nfs_ticks;
int nfs_pbuf_freecnt = -1; /* start out unlimited */
struct nfs_bufq nfs_bufq;
static struct mtx nfs_xid_mtx;
struct task nfs_nfsiodnew_task;
/*
* and the reverse mapping from generic to Version 2 procedure numbers
*/
int nfsv2_procid[NFS_NPROCS] = {
NFSV2PROC_NULL,
NFSV2PROC_GETATTR,
NFSV2PROC_SETATTR,
NFSV2PROC_LOOKUP,
NFSV2PROC_NOOP,
NFSV2PROC_READLINK,
NFSV2PROC_READ,
NFSV2PROC_WRITE,
NFSV2PROC_CREATE,
NFSV2PROC_MKDIR,
NFSV2PROC_SYMLINK,
NFSV2PROC_CREATE,
NFSV2PROC_REMOVE,
NFSV2PROC_RMDIR,
NFSV2PROC_RENAME,
NFSV2PROC_LINK,
NFSV2PROC_READDIR,
NFSV2PROC_NOOP,
NFSV2PROC_STATFS,
NFSV2PROC_NOOP,
NFSV2PROC_NOOP,
NFSV2PROC_NOOP,
NFSV2PROC_NOOP,
};
LIST_HEAD(nfsnodehashhead, nfsnode);
u_int32_t
nfs_xid_gen(void)
{
uint32_t xid;
mtx_lock(&nfs_xid_mtx);
/* Get a pretty random xid to start with */
if (!nfs_xid)
nfs_xid = random();
/*
* Skip zero xid if it should ever happen.
*/
if (++nfs_xid == 0)
nfs_xid++;
xid = nfs_xid;
mtx_unlock(&nfs_xid_mtx);
return xid;
}
/*
* Create the header for an rpc request packet
* The hsiz is the size of the rest of the nfs request header.
* (just used to decide if a cluster is a good idea)
*/
struct mbuf *
nfsm_reqhead(struct vnode *vp, u_long procid, int hsiz)
{
struct mbuf *mb;
MGET(mb, M_WAIT, MT_DATA);
if (hsiz >= MINCLSIZE)
MCLGET(mb, M_WAIT);
mb->m_len = 0;
return (mb);
}
/*
* copies a uio scatter/gather list to an mbuf chain.
* NOTE: can ony handle iovcnt == 1
*/
int
nfsm_uiotombuf(struct uio *uiop, struct mbuf **mq, int siz, caddr_t *bpos)
{
char *uiocp;
struct mbuf *mp, *mp2;
int xfer, left, mlen;
int uiosiz, clflg, rem;
char *cp;
KASSERT(uiop->uio_iovcnt == 1, ("nfsm_uiotombuf: iovcnt != 1"));
if (siz > MLEN) /* or should it >= MCLBYTES ?? */
clflg = 1;
else
clflg = 0;
rem = nfsm_rndup(siz)-siz;
mp = mp2 = *mq;
while (siz > 0) {
left = uiop->uio_iov->iov_len;
uiocp = uiop->uio_iov->iov_base;
if (left > siz)
left = siz;
uiosiz = left;
while (left > 0) {
mlen = M_TRAILINGSPACE(mp);
if (mlen == 0) {
MGET(mp, M_WAIT, MT_DATA);
if (clflg)
MCLGET(mp, M_WAIT);
mp->m_len = 0;
mp2->m_next = mp;
mp2 = mp;
mlen = M_TRAILINGSPACE(mp);
}
xfer = (left > mlen) ? mlen : left;
#ifdef notdef
/* Not Yet.. */
if (uiop->uio_iov->iov_op != NULL)
(*(uiop->uio_iov->iov_op))
(uiocp, mtod(mp, caddr_t)+mp->m_len, xfer);
else
#endif
if (uiop->uio_segflg == UIO_SYSSPACE)
bcopy(uiocp, mtod(mp, caddr_t)+mp->m_len, xfer);
else
copyin(uiocp, mtod(mp, caddr_t)+mp->m_len, xfer);
mp->m_len += xfer;
left -= xfer;
uiocp += xfer;
uiop->uio_offset += xfer;
uiop->uio_resid -= xfer;
}
uiop->uio_iov->iov_base =
(char *)uiop->uio_iov->iov_base + uiosiz;
uiop->uio_iov->iov_len -= uiosiz;
siz -= uiosiz;
}
if (rem > 0) {
if (rem > M_TRAILINGSPACE(mp)) {
MGET(mp, M_WAIT, MT_DATA);
mp->m_len = 0;
mp2->m_next = mp;
}
cp = mtod(mp, caddr_t)+mp->m_len;
for (left = 0; left < rem; left++)
*cp++ = '\0';
mp->m_len += rem;
*bpos = cp;
} else
*bpos = mtod(mp, caddr_t)+mp->m_len;
*mq = mp;
return (0);
}
/*
* Copy a string into mbufs for the hard cases...
*/
int
nfsm_strtmbuf(struct mbuf **mb, char **bpos, const char *cp, long siz)
{
struct mbuf *m1 = NULL, *m2;
long left, xfer, len, tlen;
u_int32_t *tl;
int putsize;
putsize = 1;
m2 = *mb;
left = M_TRAILINGSPACE(m2);
if (left > 0) {
tl = ((u_int32_t *)(*bpos));
*tl++ = txdr_unsigned(siz);
putsize = 0;
left -= NFSX_UNSIGNED;
m2->m_len += NFSX_UNSIGNED;
if (left > 0) {
bcopy(cp, (caddr_t) tl, left);
siz -= left;
cp += left;
m2->m_len += left;
left = 0;
}
}
/* Loop around adding mbufs */
while (siz > 0) {
MGET(m1, M_WAIT, MT_DATA);
if (siz > MLEN)
MCLGET(m1, M_WAIT);
m1->m_len = NFSMSIZ(m1);
m2->m_next = m1;
m2 = m1;
tl = mtod(m1, u_int32_t *);
tlen = 0;
if (putsize) {
*tl++ = txdr_unsigned(siz);
m1->m_len -= NFSX_UNSIGNED;
tlen = NFSX_UNSIGNED;
putsize = 0;
}
if (siz < m1->m_len) {
len = nfsm_rndup(siz);
xfer = siz;
if (xfer < len)
*(tl+(xfer>>2)) = 0;
} else {
xfer = len = m1->m_len;
}
bcopy(cp, (caddr_t) tl, xfer);
m1->m_len = len+tlen;
siz -= xfer;
cp += xfer;
}
*mb = m1;
*bpos = mtod(m1, caddr_t)+m1->m_len;
return (0);
}
/*
* Called once to initialize data structures...
*/
int
nfs_init(struct vfsconf *vfsp)
{
int i;
nfsmount_zone = uma_zcreate("NFSMOUNT", sizeof(struct nfsmount),
NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0);
nfs_true = txdr_unsigned(TRUE);
nfs_false = txdr_unsigned(FALSE);
nfs_xdrneg1 = txdr_unsigned(-1);
nfs_ticks = (hz * NFS_TICKINTVL + 500) / 1000;
if (nfs_ticks < 1)
nfs_ticks = 1;
/* Ensure async daemons disabled */
for (i = 0; i < NFS_MAXASYNCDAEMON; i++) {
nfs_iodwant[i] = NFSIOD_NOT_AVAILABLE;
nfs_iodmount[i] = NULL;
}
nfs_nhinit(); /* Init the nfsnode table */
/*
* Initialize reply list and start timer
*/
mtx_init(&nfs_iod_mtx, "NFS iod lock", NULL, MTX_DEF);
mtx_init(&nfs_xid_mtx, "NFS xid lock", NULL, MTX_DEF);
TASK_INIT(&nfs_nfsiodnew_task, 0, nfs_nfsiodnew_tq, NULL);
nfs_pbuf_freecnt = nswbuf / 2 + 1;
return (0);
}
int
nfs_uninit(struct vfsconf *vfsp)
{
int i;
/*
* Tell all nfsiod processes to exit. Clear nfs_iodmax, and wakeup
* any sleeping nfsiods so they check nfs_iodmax and exit.
* Drain nfsiodnew task before we wait for them to finish.
*/
mtx_lock(&nfs_iod_mtx);
nfs_iodmax = 0;
mtx_unlock(&nfs_iod_mtx);
taskqueue_drain(taskqueue_thread, &nfs_nfsiodnew_task);
mtx_lock(&nfs_iod_mtx);
for (i = 0; i < nfs_numasync; i++)
if (nfs_iodwant[i] == NFSIOD_AVAILABLE)
wakeup(&nfs_iodwant[i]);
/* The last nfsiod to exit will wake us up when nfs_numasync hits 0 */
while (nfs_numasync)
msleep(&nfs_numasync, &nfs_iod_mtx, PWAIT, "ioddie", 0);
mtx_unlock(&nfs_iod_mtx);
nfs_nhuninit();
uma_zdestroy(nfsmount_zone);
return (0);
}
void
nfs_dircookie_lock(struct nfsnode *np)
{
mtx_lock(&np->n_mtx);
while (np->n_flag & NDIRCOOKIELK)
(void) msleep(&np->n_flag, &np->n_mtx, PZERO, "nfsdirlk", 0);
np->n_flag |= NDIRCOOKIELK;
mtx_unlock(&np->n_mtx);
}
void
nfs_dircookie_unlock(struct nfsnode *np)
{
mtx_lock(&np->n_mtx);
np->n_flag &= ~NDIRCOOKIELK;
wakeup(&np->n_flag);
mtx_unlock(&np->n_mtx);
}
int
nfs_upgrade_vnlock(struct vnode *vp)
{
int old_lock;
ASSERT_VOP_LOCKED(vp, "nfs_upgrade_vnlock");
old_lock = VOP_ISLOCKED(vp);
if (old_lock != LK_EXCLUSIVE) {
KASSERT(old_lock == LK_SHARED,
("nfs_upgrade_vnlock: wrong old_lock %d", old_lock));
/* Upgrade to exclusive lock, this might block */
vn_lock(vp, LK_UPGRADE | LK_RETRY);
}
return (old_lock);
}
void
nfs_downgrade_vnlock(struct vnode *vp, int old_lock)
{
if (old_lock != LK_EXCLUSIVE) {
KASSERT(old_lock == LK_SHARED, ("wrong old_lock %d", old_lock));
/* Downgrade from exclusive lock. */
vn_lock(vp, LK_DOWNGRADE | LK_RETRY);
}
}
void
nfs_printf(const char *fmt, ...)
{
va_list ap;
mtx_lock(&Giant);
va_start(ap, fmt);
vprintf(fmt, ap);
va_end(ap);
mtx_unlock(&Giant);
}
/*
* Attribute cache routines.
* nfs_loadattrcache() - loads or updates the cache contents from attributes
* that are on the mbuf list
* nfs_getattrcache() - returns valid attributes if found in cache, returns
* error otherwise
*/
/*
* Load the attribute cache (that lives in the nfsnode entry) with
* the values on the mbuf list and
* Iff vap not NULL
* copy the attributes to *vaper
*/
int
nfs_loadattrcache(struct vnode **vpp, struct mbuf **mdp, caddr_t *dposp,
struct vattr *vaper, int dontshrink)
{
struct vnode *vp = *vpp;
struct vattr *vap;
struct nfs_fattr *fp;
struct nfsnode *np = NULL;
int32_t t1;
caddr_t cp2;
int rdev;
struct mbuf *md;
enum vtype vtyp;
u_short vmode;
struct timespec mtime, mtime_save;
int v3 = NFS_ISV3(vp);
int error = 0;
md = *mdp;
t1 = (mtod(md, caddr_t) + md->m_len) - *dposp;
cp2 = nfsm_disct(mdp, dposp, NFSX_FATTR(v3), t1, M_WAIT);
if (cp2 == NULL) {
error = EBADRPC;
goto out;
}
fp = (struct nfs_fattr *)cp2;
if (v3) {
vtyp = nfsv3tov_type(fp->fa_type);
vmode = fxdr_unsigned(u_short, fp->fa_mode);
rdev = makedev(fxdr_unsigned(int, fp->fa3_rdev.specdata1),
fxdr_unsigned(int, fp->fa3_rdev.specdata2));
fxdr_nfsv3time(&fp->fa3_mtime, &mtime);
} else {
vtyp = nfsv2tov_type(fp->fa_type);
vmode = fxdr_unsigned(u_short, fp->fa_mode);
/*
* XXX
*
* The duplicate information returned in fa_type and fa_mode
* is an ambiguity in the NFS version 2 protocol.
*
* VREG should be taken literally as a regular file. If a
* server intents to return some type information differently
* in the upper bits of the mode field (e.g. for sockets, or
* FIFOs), NFSv2 mandates fa_type to be VNON. Anyway, we
* leave the examination of the mode bits even in the VREG
* case to avoid breakage for bogus servers, but we make sure
* that there are actually type bits set in the upper part of
* fa_mode (and failing that, trust the va_type field).
*
* NFSv3 cleared the issue, and requires fa_mode to not
* contain any type information (while also introduing sockets
* and FIFOs for fa_type).
*/
if (vtyp == VNON || (vtyp == VREG && (vmode & S_IFMT) != 0))
vtyp = IFTOVT(vmode);
rdev = fxdr_unsigned(int32_t, fp->fa2_rdev);
fxdr_nfsv2time(&fp->fa2_mtime, &mtime);
/*
* Really ugly NFSv2 kludge.
*/
if (vtyp == VCHR && rdev == 0xffffffff)
vtyp = VFIFO;
}
/*
* If v_type == VNON it is a new node, so fill in the v_type,
* n_mtime fields. Check to see if it represents a special
* device, and if so, check for a possible alias. Once the
* correct vnode has been obtained, fill in the rest of the
* information.
*/
np = VTONFS(vp);
mtx_lock(&np->n_mtx);
if (vp->v_type != vtyp) {
vp->v_type = vtyp;
if (vp->v_type == VFIFO)
vp->v_op = &nfs_fifoops;
np->n_mtime = mtime;
}
vap = &np->n_vattr;
vap->va_type = vtyp;
vap->va_mode = (vmode & 07777);
vap->va_rdev = rdev;
mtime_save = vap->va_mtime;
vap->va_mtime = mtime;
vap->va_fsid = vp->v_mount->mnt_stat.f_fsid.val[0];
if (v3) {
vap->va_nlink = fxdr_unsigned(u_short, fp->fa_nlink);
vap->va_uid = fxdr_unsigned(uid_t, fp->fa_uid);
vap->va_gid = fxdr_unsigned(gid_t, fp->fa_gid);
vap->va_size = fxdr_hyper(&fp->fa3_size);
vap->va_blocksize = NFS_FABLKSIZE;
vap->va_bytes = fxdr_hyper(&fp->fa3_used);
vap->va_fileid = fxdr_unsigned(int32_t,
fp->fa3_fileid.nfsuquad[1]);
fxdr_nfsv3time(&fp->fa3_atime, &vap->va_atime);
fxdr_nfsv3time(&fp->fa3_ctime, &vap->va_ctime);
vap->va_flags = 0;
vap->va_filerev = 0;
} else {
vap->va_nlink = fxdr_unsigned(u_short, fp->fa_nlink);
vap->va_uid = fxdr_unsigned(uid_t, fp->fa_uid);
vap->va_gid = fxdr_unsigned(gid_t, fp->fa_gid);
vap->va_size = fxdr_unsigned(u_int32_t, fp->fa2_size);
vap->va_blocksize = fxdr_unsigned(int32_t, fp->fa2_blocksize);
vap->va_bytes = (u_quad_t)fxdr_unsigned(int32_t, fp->fa2_blocks)
* NFS_FABLKSIZE;
vap->va_fileid = fxdr_unsigned(int32_t, fp->fa2_fileid);
fxdr_nfsv2time(&fp->fa2_atime, &vap->va_atime);
vap->va_flags = 0;
vap->va_ctime.tv_sec = fxdr_unsigned(u_int32_t,
fp->fa2_ctime.nfsv2_sec);
vap->va_ctime.tv_nsec = 0;
vap->va_gen = fxdr_unsigned(u_int32_t, fp->fa2_ctime.nfsv2_usec);
vap->va_filerev = 0;
}
np->n_attrstamp = time_second;
if (vap->va_size != np->n_size) {
if (vap->va_type == VREG) {
if (dontshrink && vap->va_size < np->n_size) {
/*
* We've been told not to shrink the file;
* zero np->n_attrstamp to indicate that
* the attributes are stale.
*/
vap->va_size = np->n_size;
np->n_attrstamp = 0;
KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(vp);
} else if (np->n_flag & NMODIFIED) {
/*
* We've modified the file: Use the larger
* of our size, and the server's size.
*/
if (vap->va_size < np->n_size) {
vap->va_size = np->n_size;
} else {
np->n_size = vap->va_size;
np->n_flag |= NSIZECHANGED;
}
} else {
np->n_size = vap->va_size;
np->n_flag |= NSIZECHANGED;
}
vnode_pager_setsize(vp, np->n_size);
} else {
np->n_size = vap->va_size;
}
}
/*
* The following checks are added to prevent a race between (say)
* a READDIR+ and a WRITE.
* READDIR+, WRITE requests sent out.
* READDIR+ resp, WRITE resp received on client.
* However, the WRITE resp was handled before the READDIR+ resp
* causing the post op attrs from the write to be loaded first
* and the attrs from the READDIR+ to be loaded later. If this
* happens, we have stale attrs loaded into the attrcache.
* We detect this by for the mtime moving back. We invalidate the
* attrcache when this happens.
*/
if (timespeccmp(&mtime_save, &vap->va_mtime, >)) {
/* Size changed or mtime went backwards */
np->n_attrstamp = 0;
KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(vp);
}
if (vaper != NULL) {
bcopy((caddr_t)vap, (caddr_t)vaper, sizeof(*vap));
if (np->n_flag & NCHG) {
if (np->n_flag & NACC)
vaper->va_atime = np->n_atim;
if (np->n_flag & NUPD)
vaper->va_mtime = np->n_mtim;
}
}
#ifdef KDTRACE_HOOKS
if (np->n_attrstamp != 0)
KDTRACE_NFS_ATTRCACHE_LOAD_DONE(vp, &np->n_vattr, 0);
#endif
mtx_unlock(&np->n_mtx);
out:
#ifdef KDTRACE_HOOKS
if (error)
KDTRACE_NFS_ATTRCACHE_LOAD_DONE(vp, NULL, error);
#endif
return (error);
}
#ifdef NFS_ACDEBUG
#include <sys/sysctl.h>
SYSCTL_DECL(_vfs_oldnfs);
static int nfs_acdebug;
SYSCTL_INT(_vfs_oldnfs, OID_AUTO, acdebug, CTLFLAG_RW, &nfs_acdebug, 0,
"Toggle acdebug (attribute cache debug) flag");
#endif
/*
* Check the time stamp
* If the cache is valid, copy contents to *vap and return 0
* otherwise return an error
*/
int
nfs_getattrcache(struct vnode *vp, struct vattr *vaper)
{
struct nfsnode *np;
struct vattr *vap;
struct nfsmount *nmp;
int timeo;
np = VTONFS(vp);
vap = &np->n_vattr;
nmp = VFSTONFS(vp->v_mount);
#ifdef NFS_ACDEBUG
mtx_lock(&Giant); /* nfs_printf() */
#endif
mtx_lock(&np->n_mtx);
/* XXX n_mtime doesn't seem to be updated on a miss-and-reload */
timeo = (time_second - np->n_mtime.tv_sec) / 10;
#ifdef NFS_ACDEBUG
if (nfs_acdebug>1)
nfs_printf("nfs_getattrcache: initial timeo = %d\n", timeo);
#endif
if (vap->va_type == VDIR) {
if ((np->n_flag & NMODIFIED) || timeo < nmp->nm_acdirmin)
timeo = nmp->nm_acdirmin;
else if (timeo > nmp->nm_acdirmax)
timeo = nmp->nm_acdirmax;
} else {
if ((np->n_flag & NMODIFIED) || timeo < nmp->nm_acregmin)
timeo = nmp->nm_acregmin;
else if (timeo > nmp->nm_acregmax)
timeo = nmp->nm_acregmax;
}
#ifdef NFS_ACDEBUG
if (nfs_acdebug > 2)
nfs_printf("acregmin %d; acregmax %d; acdirmin %d; acdirmax %d\n",
nmp->nm_acregmin, nmp->nm_acregmax,
nmp->nm_acdirmin, nmp->nm_acdirmax);
if (nfs_acdebug)
nfs_printf("nfs_getattrcache: age = %d; final timeo = %d\n",
(time_second - np->n_attrstamp), timeo);
#endif
if ((time_second - np->n_attrstamp) >= timeo) {
nfsstats.attrcache_misses++;
mtx_unlock(&np->n_mtx);
#ifdef NFS_ACDEBUG
mtx_unlock(&Giant); /* nfs_printf() */
#endif
KDTRACE_NFS_ATTRCACHE_GET_MISS(vp);
return (ENOENT);
}
nfsstats.attrcache_hits++;
if (vap->va_size != np->n_size) {
if (vap->va_type == VREG) {
if (np->n_flag & NMODIFIED) {
if (vap->va_size < np->n_size)
vap->va_size = np->n_size;
else
np->n_size = vap->va_size;
} else {
np->n_size = vap->va_size;
}
vnode_pager_setsize(vp, np->n_size);
} else {
np->n_size = vap->va_size;
}
}
bcopy((caddr_t)vap, (caddr_t)vaper, sizeof(struct vattr));
if (np->n_flag & NCHG) {
if (np->n_flag & NACC)
vaper->va_atime = np->n_atim;
if (np->n_flag & NUPD)
vaper->va_mtime = np->n_mtim;
}
mtx_unlock(&np->n_mtx);
#ifdef NFS_ACDEBUG
mtx_unlock(&Giant); /* nfs_printf() */
#endif
KDTRACE_NFS_ATTRCACHE_GET_HIT(vp, vap);
return (0);
}
/*
* Purge all cached information about an NFS vnode including name
* cache entries, the attribute cache, and the access cache. This is
* called when an NFS request for a node fails with a stale
* filehandle.
*/
void
nfs_purgecache(struct vnode *vp)
{
struct nfsnode *np;
int i;
np = VTONFS(vp);
cache_purge(vp);
mtx_lock(&np->n_mtx);
np->n_attrstamp = 0;
KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(vp);
for (i = 0; i < NFS_ACCESSCACHESIZE; i++)
np->n_accesscache[i].stamp = 0;
KDTRACE_NFS_ACCESSCACHE_FLUSH_DONE(vp);
mtx_unlock(&np->n_mtx);
}
static nfsuint64 nfs_nullcookie = { { 0, 0 } };
/*
* This function finds the directory cookie that corresponds to the
* logical byte offset given.
*/
nfsuint64 *
nfs_getcookie(struct nfsnode *np, off_t off, int add)
{
struct nfsdmap *dp, *dp2;
int pos;
nfsuint64 *retval = NULL;
pos = (uoff_t)off / NFS_DIRBLKSIZ;
if (pos == 0 || off < 0) {
KASSERT(!add, ("nfs getcookie add at <= 0"));
return (&nfs_nullcookie);
}
pos--;
dp = LIST_FIRST(&np->n_cookies);
if (!dp) {
if (add) {
dp = malloc(sizeof (struct nfsdmap),
M_NFSDIROFF, M_WAITOK);
dp->ndm_eocookie = 0;
LIST_INSERT_HEAD(&np->n_cookies, dp, ndm_list);
} else
goto out;
}
while (pos >= NFSNUMCOOKIES) {
pos -= NFSNUMCOOKIES;
if (LIST_NEXT(dp, ndm_list)) {
if (!add && dp->ndm_eocookie < NFSNUMCOOKIES &&
pos >= dp->ndm_eocookie)
goto out;
dp = LIST_NEXT(dp, ndm_list);
} else if (add) {
dp2 = malloc(sizeof (struct nfsdmap),
M_NFSDIROFF, M_WAITOK);
dp2->ndm_eocookie = 0;
LIST_INSERT_AFTER(dp, dp2, ndm_list);
dp = dp2;
} else
goto out;
}
if (pos >= dp->ndm_eocookie) {
if (add)
dp->ndm_eocookie = pos + 1;
else
goto out;
}
retval = &dp->ndm_cookies[pos];
out:
return (retval);
}
/*
* Invalidate cached directory information, except for the actual directory
* blocks (which are invalidated separately).
* Done mainly to avoid the use of stale offset cookies.
*/
void
nfs_invaldir(struct vnode *vp)
{
struct nfsnode *np = VTONFS(vp);
KASSERT(vp->v_type == VDIR, ("nfs: invaldir not dir"));
nfs_dircookie_lock(np);
np->n_direofoffset = 0;
np->n_cookieverf.nfsuquad[0] = 0;
np->n_cookieverf.nfsuquad[1] = 0;
if (LIST_FIRST(&np->n_cookies))
LIST_FIRST(&np->n_cookies)->ndm_eocookie = 0;
nfs_dircookie_unlock(np);
}
/*
* The write verifier has changed (probably due to a server reboot), so all
* B_NEEDCOMMIT blocks will have to be written again. Since they are on the
* dirty block list as B_DELWRI, all this takes is clearing the B_NEEDCOMMIT
* and B_CLUSTEROK flags. Once done the new write verifier can be set for the
* mount point.
*
* B_CLUSTEROK must be cleared along with B_NEEDCOMMIT because stage 1 data
* writes are not clusterable.
*/
void
nfs_clearcommit(struct mount *mp)
{
struct vnode *vp, *nvp;
struct buf *bp, *nbp;
struct bufobj *bo;
MNT_ILOCK(mp);
MNT_VNODE_FOREACH(vp, mp, nvp) {
bo = &vp->v_bufobj;
VI_LOCK(vp);
if (vp->v_iflag & VI_DOOMED) {
VI_UNLOCK(vp);
continue;
}
vholdl(vp);
VI_UNLOCK(vp);
MNT_IUNLOCK(mp);
BO_LOCK(bo);
TAILQ_FOREACH_SAFE(bp, &bo->bo_dirty.bv_hd, b_bobufs, nbp) {
if (!BUF_ISLOCKED(bp) &&
(bp->b_flags & (B_DELWRI | B_NEEDCOMMIT))
== (B_DELWRI | B_NEEDCOMMIT))
bp->b_flags &= ~(B_NEEDCOMMIT | B_CLUSTEROK);
}
BO_UNLOCK(bo);
vdrop(vp);
MNT_ILOCK(mp);
}
MNT_IUNLOCK(mp);
}
/*
* Helper functions for former macros. Some of these should be
* moved to their callers.
*/
int
nfsm_mtofh_xx(struct vnode *d, struct vnode **v, int v3, int *f,
struct mbuf **md, caddr_t *dpos)
{
struct nfsnode *ttnp;
struct vnode *ttvp;
nfsfh_t *ttfhp;
u_int32_t *tl;
int ttfhsize;
int t1;
if (v3) {
tl = nfsm_dissect_xx(NFSX_UNSIGNED, md, dpos);
if (tl == NULL)
return EBADRPC;
*f = fxdr_unsigned(int, *tl);
} else
*f = 1;
if (*f) {
t1 = nfsm_getfh_xx(&ttfhp, &ttfhsize, (v3), md, dpos);
if (t1 != 0)
return t1;
t1 = nfs_nget(d->v_mount, ttfhp, ttfhsize, &ttnp, LK_EXCLUSIVE);
if (t1 != 0)
return t1;
*v = NFSTOV(ttnp);
}
if (v3) {
tl = nfsm_dissect_xx(NFSX_UNSIGNED, md, dpos);
if (tl == NULL)
return EBADRPC;
if (*f)
*f = fxdr_unsigned(int, *tl);
else if (fxdr_unsigned(int, *tl))
nfsm_adv_xx(NFSX_V3FATTR, md, dpos);
}
if (*f) {
ttvp = *v;
t1 = nfs_loadattrcache(&ttvp, md, dpos, NULL, 0);
if (t1)
return t1;
*v = ttvp;
}
return 0;
}
int
nfsm_getfh_xx(nfsfh_t **f, int *s, int v3, struct mbuf **md, caddr_t *dpos)
{
u_int32_t *tl;
if (v3) {
tl = nfsm_dissect_xx(NFSX_UNSIGNED, md, dpos);
if (tl == NULL)
return EBADRPC;
*s = fxdr_unsigned(int, *tl);
if (*s <= 0 || *s > NFSX_V3FHMAX)
return EBADRPC;
} else
*s = NFSX_V2FH;
*f = nfsm_dissect_xx(nfsm_rndup(*s), md, dpos);
if (*f == NULL)
return EBADRPC;
else
return 0;
}
int
nfsm_loadattr_xx(struct vnode **v, struct vattr *va, struct mbuf **md,
caddr_t *dpos)
{
int t1;
struct vnode *ttvp = *v;
t1 = nfs_loadattrcache(&ttvp, md, dpos, va, 0);
if (t1 != 0)
return t1;
*v = ttvp;
return 0;
}
int
nfsm_postop_attr_xx(struct vnode **v, int *f, struct vattr *va,
struct mbuf **md, caddr_t *dpos)
{
u_int32_t *tl;
int t1;
struct vnode *ttvp = *v;
tl = nfsm_dissect_xx(NFSX_UNSIGNED, md, dpos);
if (tl == NULL)
return EBADRPC;
*f = fxdr_unsigned(int, *tl);
if (*f != 0) {
t1 = nfs_loadattrcache(&ttvp, md, dpos, va, 1);
if (t1 != 0) {
*f = 0;
return t1;
}
*v = ttvp;
}
return 0;
}
int
nfsm_wcc_data_xx(struct vnode **v, int *f, struct mbuf **md, caddr_t *dpos)
{
u_int32_t *tl;
int ttattrf, ttretf = 0;
int t1;
tl = nfsm_dissect_xx(NFSX_UNSIGNED, md, dpos);
if (tl == NULL)
return EBADRPC;
if (*tl == nfs_true) {
tl = nfsm_dissect_xx(6 * NFSX_UNSIGNED, md, dpos);
if (tl == NULL)
return EBADRPC;
mtx_lock(&(VTONFS(*v))->n_mtx);
if (*f)
ttretf = (VTONFS(*v)->n_mtime.tv_sec == fxdr_unsigned(u_int32_t, *(tl + 2)) &&
VTONFS(*v)->n_mtime.tv_nsec == fxdr_unsigned(u_int32_t, *(tl + 3)));
mtx_unlock(&(VTONFS(*v))->n_mtx);
}
t1 = nfsm_postop_attr_xx(v, &ttattrf, NULL, md, dpos);
if (t1)
return t1;
if (*f)
*f = ttretf;
else
*f = ttattrf;
return 0;
}
int
nfsm_strtom_xx(const char *a, int s, int m, struct mbuf **mb, caddr_t *bpos)
{
u_int32_t *tl;
int t1;
if (s > m)
return ENAMETOOLONG;
t1 = nfsm_rndup(s) + NFSX_UNSIGNED;
if (t1 <= M_TRAILINGSPACE(*mb)) {
tl = nfsm_build_xx(t1, mb, bpos);
*tl++ = txdr_unsigned(s);
*(tl + ((t1 >> 2) - 2)) = 0;
bcopy(a, tl, s);
} else {
t1 = nfsm_strtmbuf(mb, bpos, a, s);
if (t1 != 0)
return t1;
}
return 0;
}
int
nfsm_fhtom_xx(struct vnode *v, int v3, struct mbuf **mb, caddr_t *bpos)
{
u_int32_t *tl;
int t1;
caddr_t cp;
if (v3) {
t1 = nfsm_rndup(VTONFS(v)->n_fhsize) + NFSX_UNSIGNED;
if (t1 < M_TRAILINGSPACE(*mb)) {
tl = nfsm_build_xx(t1, mb, bpos);
*tl++ = txdr_unsigned(VTONFS(v)->n_fhsize);
*(tl + ((t1 >> 2) - 2)) = 0;
bcopy(VTONFS(v)->n_fhp, tl, VTONFS(v)->n_fhsize);
} else {
t1 = nfsm_strtmbuf(mb, bpos,
(const char *)VTONFS(v)->n_fhp,
VTONFS(v)->n_fhsize);
if (t1 != 0)
return t1;
}
} else {
cp = nfsm_build_xx(NFSX_V2FH, mb, bpos);
bcopy(VTONFS(v)->n_fhp, cp, NFSX_V2FH);
}
return 0;
}
void
nfsm_v3attrbuild_xx(struct vattr *va, int full, struct mbuf **mb,
caddr_t *bpos)
{
u_int32_t *tl;
if (va->va_mode != (mode_t)VNOVAL) {
tl = nfsm_build_xx(2 * NFSX_UNSIGNED, mb, bpos);
*tl++ = nfs_true;
*tl = txdr_unsigned(va->va_mode);
} else {
tl = nfsm_build_xx(NFSX_UNSIGNED, mb, bpos);
*tl = nfs_false;
}
if (full && va->va_uid != (uid_t)VNOVAL) {
tl = nfsm_build_xx(2 * NFSX_UNSIGNED, mb, bpos);
*tl++ = nfs_true;
*tl = txdr_unsigned(va->va_uid);
} else {
tl = nfsm_build_xx(NFSX_UNSIGNED, mb, bpos);
*tl = nfs_false;
}
if (full && va->va_gid != (gid_t)VNOVAL) {
tl = nfsm_build_xx(2 * NFSX_UNSIGNED, mb, bpos);
*tl++ = nfs_true;
*tl = txdr_unsigned(va->va_gid);
} else {
tl = nfsm_build_xx(NFSX_UNSIGNED, mb, bpos);
*tl = nfs_false;
}
if (full && va->va_size != VNOVAL) {
tl = nfsm_build_xx(3 * NFSX_UNSIGNED, mb, bpos);
*tl++ = nfs_true;
txdr_hyper(va->va_size, tl);
} else {
tl = nfsm_build_xx(NFSX_UNSIGNED, mb, bpos);
*tl = nfs_false;
}
if (va->va_atime.tv_sec != VNOVAL) {
if (va->va_atime.tv_sec != time_second) {
tl = nfsm_build_xx(3 * NFSX_UNSIGNED, mb, bpos);
*tl++ = txdr_unsigned(NFSV3SATTRTIME_TOCLIENT);
txdr_nfsv3time(&va->va_atime, tl);
} else {
tl = nfsm_build_xx(NFSX_UNSIGNED, mb, bpos);
*tl = txdr_unsigned(NFSV3SATTRTIME_TOSERVER);
}
} else {
tl = nfsm_build_xx(NFSX_UNSIGNED, mb, bpos);
*tl = txdr_unsigned(NFSV3SATTRTIME_DONTCHANGE);
}
if (va->va_mtime.tv_sec != VNOVAL) {
if (va->va_mtime.tv_sec != time_second) {
tl = nfsm_build_xx(3 * NFSX_UNSIGNED, mb, bpos);
*tl++ = txdr_unsigned(NFSV3SATTRTIME_TOCLIENT);
txdr_nfsv3time(&va->va_mtime, tl);
} else {
tl = nfsm_build_xx(NFSX_UNSIGNED, mb, bpos);
*tl = txdr_unsigned(NFSV3SATTRTIME_TOSERVER);
}
} else {
tl = nfsm_build_xx(NFSX_UNSIGNED, mb, bpos);
*tl = txdr_unsigned(NFSV3SATTRTIME_DONTCHANGE);
}
}
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