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-rw-r--r--sys/nfs/nfs_bio.c1555
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diff --git a/sys/nfs/nfs_bio.c b/sys/nfs/nfs_bio.c
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+++ b/sys/nfs/nfs_bio.c
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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.
+ * 3. All advertising materials mentioning features or use of this software
+ * must display the following acknowledgement:
+ * This product includes software developed by the University of
+ * California, Berkeley and its contributors.
+ * 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_bio.c 8.9 (Berkeley) 3/30/95
+ * $FreeBSD$
+ */
+
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/resourcevar.h>
+#include <sys/signalvar.h>
+#include <sys/proc.h>
+#include <sys/buf.h>
+#include <sys/vnode.h>
+#include <sys/mount.h>
+#include <sys/kernel.h>
+
+#include <vm/vm.h>
+#include <vm/vm_extern.h>
+#include <vm/vm_page.h>
+#include <vm/vm_object.h>
+#include <vm/vm_pager.h>
+#include <vm/vnode_pager.h>
+
+#include <nfs/rpcv2.h>
+#include <nfs/nfsproto.h>
+#include <nfs/nfs.h>
+#include <nfs/nfsmount.h>
+#include <nfs/nqnfs.h>
+#include <nfs/nfsnode.h>
+
+static struct buf *nfs_getcacheblk __P((struct vnode *vp, daddr_t bn, int size,
+ struct proc *p));
+
+extern int nfs_numasync;
+extern int nfs_pbuf_freecnt;
+extern struct nfsstats nfsstats;
+
+/*
+ * Vnode op for VM getpages.
+ */
+int
+nfs_getpages(ap)
+ struct vop_getpages_args /* {
+ struct vnode *a_vp;
+ vm_page_t *a_m;
+ int a_count;
+ int a_reqpage;
+ vm_ooffset_t a_offset;
+ } */ *ap;
+{
+ int i, error, nextoff, size, toff, count, npages;
+ struct uio uio;
+ struct iovec iov;
+ vm_offset_t kva;
+ struct buf *bp;
+ struct vnode *vp;
+ struct proc *p;
+ struct ucred *cred;
+ struct nfsmount *nmp;
+ vm_page_t *pages;
+
+ vp = ap->a_vp;
+ p = curproc; /* XXX */
+ cred = curproc->p_ucred; /* XXX */
+ nmp = VFSTONFS(vp->v_mount);
+ pages = ap->a_m;
+ count = ap->a_count;
+
+ if (vp->v_object == NULL) {
+ printf("nfs_getpages: called with non-merged cache vnode??\n");
+ return VM_PAGER_ERROR;
+ }
+
+ if ((nmp->nm_flag & NFSMNT_NFSV3) != 0 &&
+ (nmp->nm_state & NFSSTA_GOTFSINFO) == 0)
+ (void)nfs_fsinfo(nmp, vp, cred, p);
+
+ npages = btoc(count);
+
+ /*
+ * If the requested page is partially valid, just return it and
+ * allow the pager to zero-out the blanks. Partially valid pages
+ * can only occur at the file EOF.
+ */
+
+ {
+ vm_page_t m = pages[ap->a_reqpage];
+
+ if (m->valid != 0) {
+ /* handled by vm_fault now */
+ /* vm_page_zero_invalid(m, TRUE); */
+ for (i = 0; i < npages; ++i) {
+ if (i != ap->a_reqpage)
+ vnode_pager_freepage(pages[i]);
+ }
+ return(0);
+ }
+ }
+
+ /*
+ * We use only the kva address for the buffer, but this is extremely
+ * convienient and fast.
+ */
+ bp = getpbuf(&nfs_pbuf_freecnt);
+
+ kva = (vm_offset_t) bp->b_data;
+ pmap_qenter(kva, pages, npages);
+
+ iov.iov_base = (caddr_t) kva;
+ iov.iov_len = count;
+ uio.uio_iov = &iov;
+ uio.uio_iovcnt = 1;
+ uio.uio_offset = IDX_TO_OFF(pages[0]->pindex);
+ uio.uio_resid = count;
+ uio.uio_segflg = UIO_SYSSPACE;
+ uio.uio_rw = UIO_READ;
+ uio.uio_procp = p;
+
+ error = nfs_readrpc(vp, &uio, cred);
+ pmap_qremove(kva, npages);
+
+ relpbuf(bp, &nfs_pbuf_freecnt);
+
+ if (error && (uio.uio_resid == count)) {
+ printf("nfs_getpages: error %d\n", error);
+ for (i = 0; i < npages; ++i) {
+ if (i != ap->a_reqpage)
+ vnode_pager_freepage(pages[i]);
+ }
+ return VM_PAGER_ERROR;
+ }
+
+ /*
+ * Calculate the number of bytes read and validate only that number
+ * of bytes. Note that due to pending writes, size may be 0. This
+ * does not mean that the remaining data is invalid!
+ */
+
+ size = count - uio.uio_resid;
+
+ for (i = 0, toff = 0; i < npages; i++, toff = nextoff) {
+ vm_page_t m;
+ nextoff = toff + PAGE_SIZE;
+ m = pages[i];
+
+ m->flags &= ~PG_ZERO;
+
+ if (nextoff <= size) {
+ /*
+ * Read operation filled an entire page
+ */
+ m->valid = VM_PAGE_BITS_ALL;
+ vm_page_undirty(m);
+ } else if (size > toff) {
+ /*
+ * Read operation filled a partial page.
+ */
+ m->valid = 0;
+ vm_page_set_validclean(m, 0, size - toff);
+ /* handled by vm_fault now */
+ /* vm_page_zero_invalid(m, TRUE); */
+ }
+
+ if (i != ap->a_reqpage) {
+ /*
+ * Whether or not to leave the page activated is up in
+ * the air, but we should put the page on a page queue
+ * somewhere (it already is in the object). Result:
+ * It appears that emperical results show that
+ * deactivating pages is best.
+ */
+
+ /*
+ * Just in case someone was asking for this page we
+ * now tell them that it is ok to use.
+ */
+ if (!error) {
+ if (m->flags & PG_WANTED)
+ vm_page_activate(m);
+ else
+ vm_page_deactivate(m);
+ vm_page_wakeup(m);
+ } else {
+ vnode_pager_freepage(m);
+ }
+ }
+ }
+ return 0;
+}
+
+/*
+ * Vnode op for VM putpages.
+ */
+int
+nfs_putpages(ap)
+ struct vop_putpages_args /* {
+ struct vnode *a_vp;
+ vm_page_t *a_m;
+ int a_count;
+ int a_sync;
+ int *a_rtvals;
+ vm_ooffset_t a_offset;
+ } */ *ap;
+{
+ struct uio uio;
+ struct iovec iov;
+ vm_offset_t kva;
+ struct buf *bp;
+ int iomode, must_commit, i, error, npages, count;
+ off_t offset;
+ int *rtvals;
+ struct vnode *vp;
+ struct proc *p;
+ struct ucred *cred;
+ struct nfsmount *nmp;
+ struct nfsnode *np;
+ vm_page_t *pages;
+
+ vp = ap->a_vp;
+ np = VTONFS(vp);
+ p = curproc; /* XXX */
+ cred = curproc->p_ucred; /* XXX */
+ nmp = VFSTONFS(vp->v_mount);
+ pages = ap->a_m;
+ count = ap->a_count;
+ rtvals = ap->a_rtvals;
+ npages = btoc(count);
+ offset = IDX_TO_OFF(pages[0]->pindex);
+
+ if ((nmp->nm_flag & NFSMNT_NFSV3) != 0 &&
+ (nmp->nm_state & NFSSTA_GOTFSINFO) == 0)
+ (void)nfs_fsinfo(nmp, vp, cred, p);
+
+ for (i = 0; i < npages; i++) {
+ rtvals[i] = VM_PAGER_AGAIN;
+ }
+
+ /*
+ * When putting pages, do not extend file past EOF.
+ */
+
+ if (offset + count > np->n_size) {
+ count = np->n_size - offset;
+ if (count < 0)
+ count = 0;
+ }
+
+ /*
+ * We use only the kva address for the buffer, but this is extremely
+ * convienient and fast.
+ */
+ bp = getpbuf(&nfs_pbuf_freecnt);
+
+ kva = (vm_offset_t) bp->b_data;
+ pmap_qenter(kva, pages, npages);
+
+ iov.iov_base = (caddr_t) kva;
+ iov.iov_len = count;
+ uio.uio_iov = &iov;
+ uio.uio_iovcnt = 1;
+ uio.uio_offset = offset;
+ uio.uio_resid = count;
+ uio.uio_segflg = UIO_SYSSPACE;
+ uio.uio_rw = UIO_WRITE;
+ uio.uio_procp = p;
+
+ if ((ap->a_sync & VM_PAGER_PUT_SYNC) == 0)
+ iomode = NFSV3WRITE_UNSTABLE;
+ else
+ iomode = NFSV3WRITE_FILESYNC;
+
+ error = nfs_writerpc(vp, &uio, cred, &iomode, &must_commit);
+
+ pmap_qremove(kva, npages);
+ relpbuf(bp, &nfs_pbuf_freecnt);
+
+ if (!error) {
+ int nwritten = round_page(count - uio.uio_resid) / PAGE_SIZE;
+ for (i = 0; i < nwritten; i++) {
+ rtvals[i] = VM_PAGER_OK;
+ vm_page_undirty(pages[i]);
+ }
+ if (must_commit)
+ nfs_clearcommit(vp->v_mount);
+ }
+ return rtvals[0];
+}
+
+/*
+ * Vnode op for read using bio
+ */
+int
+nfs_bioread(vp, uio, ioflag, cred)
+ register struct vnode *vp;
+ register struct uio *uio;
+ int ioflag;
+ struct ucred *cred;
+{
+ register struct nfsnode *np = VTONFS(vp);
+ register int biosize, i;
+ struct buf *bp = 0, *rabp;
+ struct vattr vattr;
+ struct proc *p;
+ struct nfsmount *nmp = VFSTONFS(vp->v_mount);
+ daddr_t lbn, rabn;
+ int bcount;
+ int seqcount;
+ int nra, error = 0, n = 0, on = 0;
+
+#ifdef DIAGNOSTIC
+ if (uio->uio_rw != UIO_READ)
+ panic("nfs_read mode");
+#endif
+ if (uio->uio_resid == 0)
+ return (0);
+ if (uio->uio_offset < 0) /* XXX VDIR cookies can be negative */
+ return (EINVAL);
+ p = uio->uio_procp;
+
+ if ((nmp->nm_flag & NFSMNT_NFSV3) != 0 &&
+ (nmp->nm_state & NFSSTA_GOTFSINFO) == 0)
+ (void)nfs_fsinfo(nmp, vp, cred, p);
+ if (vp->v_type != VDIR &&
+ (uio->uio_offset + uio->uio_resid) > nmp->nm_maxfilesize)
+ return (EFBIG);
+ biosize = vp->v_mount->mnt_stat.f_iosize;
+ seqcount = (int)((off_t)(ioflag >> 16) * biosize / BKVASIZE);
+ /*
+ * For nfs, cache consistency can only be maintained approximately.
+ * Although RFC1094 does not specify the criteria, the following is
+ * believed to be compatible with the reference port.
+ * For nqnfs, full cache consistency is maintained within the loop.
+ * For nfs:
+ * If the file's modify time on the server has changed since the
+ * last read rpc or you have written to the file,
+ * you may have lost data cache consistency with the
+ * server, so flush all of the file's data out of the cache.
+ * Then force a getattr rpc to ensure that you have up to date
+ * attributes.
+ * NB: This implies that cache data can be read when up to
+ * NFS_ATTRTIMEO seconds out of date. If you find that you need current
+ * attributes this could be forced by setting n_attrstamp to 0 before
+ * the VOP_GETATTR() call.
+ */
+ if ((nmp->nm_flag & NFSMNT_NQNFS) == 0) {
+ if (np->n_flag & NMODIFIED) {
+ if (vp->v_type != VREG) {
+ if (vp->v_type != VDIR)
+ panic("nfs: bioread, not dir");
+ nfs_invaldir(vp);
+ error = nfs_vinvalbuf(vp, V_SAVE, cred, p, 1);
+ if (error)
+ return (error);
+ }
+ np->n_attrstamp = 0;
+ error = VOP_GETATTR(vp, &vattr, cred, p);
+ if (error)
+ return (error);
+ np->n_mtime = vattr.va_mtime.tv_sec;
+ } else {
+ error = VOP_GETATTR(vp, &vattr, cred, p);
+ if (error)
+ return (error);
+ if (np->n_mtime != vattr.va_mtime.tv_sec) {
+ if (vp->v_type == VDIR)
+ nfs_invaldir(vp);
+ error = nfs_vinvalbuf(vp, V_SAVE, cred, p, 1);
+ if (error)
+ return (error);
+ np->n_mtime = vattr.va_mtime.tv_sec;
+ }
+ }
+ }
+ do {
+
+ /*
+ * Get a valid lease. If cached data is stale, flush it.
+ */
+ if (nmp->nm_flag & NFSMNT_NQNFS) {
+ if (NQNFS_CKINVALID(vp, np, ND_READ)) {
+ do {
+ error = nqnfs_getlease(vp, ND_READ, cred, p);
+ } while (error == NQNFS_EXPIRED);
+ if (error)
+ return (error);
+ if (np->n_lrev != np->n_brev ||
+ (np->n_flag & NQNFSNONCACHE) ||
+ ((np->n_flag & NMODIFIED) && vp->v_type == VDIR)) {
+ if (vp->v_type == VDIR)
+ nfs_invaldir(vp);
+ error = nfs_vinvalbuf(vp, V_SAVE, cred, p, 1);
+ if (error)
+ return (error);
+ np->n_brev = np->n_lrev;
+ }
+ } else if (vp->v_type == VDIR && (np->n_flag & NMODIFIED)) {
+ nfs_invaldir(vp);
+ error = nfs_vinvalbuf(vp, V_SAVE, cred, p, 1);
+ if (error)
+ return (error);
+ }
+ }
+ if (np->n_flag & NQNFSNONCACHE) {
+ switch (vp->v_type) {
+ case VREG:
+ return (nfs_readrpc(vp, uio, cred));
+ case VLNK:
+ return (nfs_readlinkrpc(vp, uio, cred));
+ case VDIR:
+ break;
+ default:
+ printf(" NQNFSNONCACHE: type %x unexpected\n",
+ vp->v_type);
+ };
+ }
+ switch (vp->v_type) {
+ case VREG:
+ nfsstats.biocache_reads++;
+ lbn = uio->uio_offset / biosize;
+ on = uio->uio_offset & (biosize - 1);
+
+ /*
+ * Start the read ahead(s), as required.
+ */
+ if (nfs_numasync > 0 && nmp->nm_readahead > 0) {
+ for (nra = 0; nra < nmp->nm_readahead && nra < seqcount &&
+ (off_t)(lbn + 1 + nra) * biosize < np->n_size; nra++) {
+ rabn = lbn + 1 + nra;
+ if (!incore(vp, rabn)) {
+ rabp = nfs_getcacheblk(vp, rabn, biosize, p);
+ if (!rabp)
+ return (EINTR);
+ if ((rabp->b_flags & (B_CACHE|B_DELWRI)) == 0) {
+ rabp->b_flags |= (B_READ | B_ASYNC);
+ vfs_busy_pages(rabp, 0);
+ if (nfs_asyncio(rabp, cred, p)) {
+ rabp->b_flags |= B_INVAL|B_ERROR;
+ vfs_unbusy_pages(rabp);
+ brelse(rabp);
+ }
+ } else
+ brelse(rabp);
+ }
+ }
+ }
+
+ /*
+ * Obtain the buffer cache block. Figure out the buffer size
+ * when we are at EOF. If we are modifying the size of the
+ * buffer based on an EOF condition we need to hold
+ * nfs_rslock() through obtaining the buffer to prevent
+ * a potential writer-appender from messing with n_size.
+ * Otherwise we may accidently truncate the buffer and
+ * lose dirty data.
+ *
+ * Note that bcount is *not* DEV_BSIZE aligned.
+ */
+
+again:
+ bcount = biosize;
+ if ((off_t)lbn * biosize >= np->n_size) {
+ bcount = 0;
+ } else if ((off_t)(lbn + 1) * biosize > np->n_size) {
+ bcount = np->n_size - (off_t)lbn * biosize;
+ }
+ if (bcount != biosize && nfs_rslock(np, p) == ENOLCK)
+ goto again;
+
+ bp = nfs_getcacheblk(vp, lbn, bcount, p);
+
+ if (bcount != biosize)
+ nfs_rsunlock(np, p);
+ if (!bp)
+ return (EINTR);
+
+ /*
+ * If B_CACHE is not set, we must issue the read. If this
+ * fails, we return an error.
+ */
+
+ if ((bp->b_flags & B_CACHE) == 0) {
+ bp->b_flags |= B_READ;
+ vfs_busy_pages(bp, 0);
+ error = nfs_doio(bp, cred, p);
+ if (error) {
+ brelse(bp);
+ return (error);
+ }
+ }
+
+ /*
+ * on is the offset into the current bp. Figure out how many
+ * bytes we can copy out of the bp. Note that bcount is
+ * NOT DEV_BSIZE aligned.
+ *
+ * Then figure out how many bytes we can copy into the uio.
+ */
+
+ n = 0;
+ if (on < bcount)
+ n = min((unsigned)(bcount - on), uio->uio_resid);
+ break;
+ case VLNK:
+ nfsstats.biocache_readlinks++;
+ bp = nfs_getcacheblk(vp, (daddr_t)0, NFS_MAXPATHLEN, p);
+ if (!bp)
+ return (EINTR);
+ if ((bp->b_flags & B_CACHE) == 0) {
+ bp->b_flags |= B_READ;
+ vfs_busy_pages(bp, 0);
+ error = nfs_doio(bp, cred, p);
+ if (error) {
+ bp->b_flags |= B_ERROR;
+ brelse(bp);
+ return (error);
+ }
+ }
+ n = min(uio->uio_resid, NFS_MAXPATHLEN - bp->b_resid);
+ on = 0;
+ break;
+ case VDIR:
+ nfsstats.biocache_readdirs++;
+ if (np->n_direofoffset
+ && uio->uio_offset >= np->n_direofoffset) {
+ return (0);
+ }
+ lbn = (uoff_t)uio->uio_offset / NFS_DIRBLKSIZ;
+ on = uio->uio_offset & (NFS_DIRBLKSIZ - 1);
+ bp = nfs_getcacheblk(vp, lbn, NFS_DIRBLKSIZ, p);
+ if (!bp)
+ return (EINTR);
+ if ((bp->b_flags & B_CACHE) == 0) {
+ bp->b_flags |= B_READ;
+ vfs_busy_pages(bp, 0);
+ error = nfs_doio(bp, cred, p);
+ if (error) {
+ brelse(bp);
+ }
+ while (error == NFSERR_BAD_COOKIE) {
+ printf("got bad cookie vp %p bp %p\n", vp, bp);
+ nfs_invaldir(vp);
+ error = nfs_vinvalbuf(vp, 0, cred, p, 1);
+ /*
+ * Yuck! The directory has been modified on the
+ * server. The only way to get the block is by
+ * reading from the beginning to get all the
+ * offset cookies.
+ *
+ * Leave the last bp intact unless there is an error.
+ * Loop back up to the while if the error is another
+ * NFSERR_BAD_COOKIE (double yuch!).
+ */
+ for (i = 0; i <= lbn && !error; i++) {
+ if (np->n_direofoffset
+ && (i * NFS_DIRBLKSIZ) >= np->n_direofoffset)
+ return (0);
+ bp = nfs_getcacheblk(vp, i, NFS_DIRBLKSIZ, p);
+ if (!bp)
+ return (EINTR);
+ if ((bp->b_flags & B_CACHE) == 0) {
+ bp->b_flags |= B_READ;
+ vfs_busy_pages(bp, 0);
+ error = nfs_doio(bp, cred, p);
+ /*
+ * no error + B_INVAL == directory EOF,
+ * use the block.
+ */
+ if (error == 0 && (bp->b_flags & B_INVAL))
+ break;
+ }
+ /*
+ * An error will throw away the block and the
+ * for loop will break out. If no error and this
+ * is not the block we want, we throw away the
+ * block and go for the next one via the for loop.
+ */
+ if (error || i < lbn)
+ brelse(bp);
+ }
+ }
+ /*
+ * The above while is repeated if we hit another cookie
+ * error. If we hit an error and it wasn't a cookie error,
+ * we give up.
+ */
+ if (error)
+ return (error);
+ }
+
+ /*
+ * If not eof and read aheads are enabled, start one.
+ * (You need the current block first, so that you have the
+ * directory offset cookie of the next block.)
+ */
+ if (nfs_numasync > 0 && nmp->nm_readahead > 0 &&
+ (bp->b_flags & B_INVAL) == 0 &&
+ (np->n_direofoffset == 0 ||
+ (lbn + 1) * NFS_DIRBLKSIZ < np->n_direofoffset) &&
+ !(np->n_flag & NQNFSNONCACHE) &&
+ !incore(vp, lbn + 1)) {
+ rabp = nfs_getcacheblk(vp, lbn + 1, NFS_DIRBLKSIZ, p);
+ if (rabp) {
+ if ((rabp->b_flags & (B_CACHE|B_DELWRI)) == 0) {
+ rabp->b_flags |= (B_READ | B_ASYNC);
+ vfs_busy_pages(rabp, 0);
+ if (nfs_asyncio(rabp, cred, p)) {
+ rabp->b_flags |= B_INVAL|B_ERROR;
+ vfs_unbusy_pages(rabp);
+ brelse(rabp);
+ }
+ } else {
+ brelse(rabp);
+ }
+ }
+ }
+ /*
+ * Unlike VREG files, whos buffer size ( bp->b_bcount ) is
+ * chopped for the EOF condition, we cannot tell how large
+ * NFS directories are going to be until we hit EOF. So
+ * an NFS directory buffer is *not* chopped to its EOF. Now,
+ * it just so happens that b_resid will effectively chop it
+ * to EOF. *BUT* this information is lost if the buffer goes
+ * away and is reconstituted into a B_CACHE state ( due to
+ * being VMIO ) later. So we keep track of the directory eof
+ * in np->n_direofoffset and chop it off as an extra step
+ * right here.
+ */
+ n = lmin(uio->uio_resid, NFS_DIRBLKSIZ - bp->b_resid - on);
+ if (np->n_direofoffset && n > np->n_direofoffset - uio->uio_offset)
+ n = np->n_direofoffset - uio->uio_offset;
+ break;
+ default:
+ printf(" nfs_bioread: type %x unexpected\n",vp->v_type);
+ break;
+ };
+
+ if (n > 0) {
+ error = uiomove(bp->b_data + on, (int)n, uio);
+ }
+ switch (vp->v_type) {
+ case VREG:
+ break;
+ case VLNK:
+ n = 0;
+ break;
+ case VDIR:
+ /*
+ * Invalidate buffer if caching is disabled, forcing a
+ * re-read from the remote later.
+ */
+ if (np->n_flag & NQNFSNONCACHE)
+ bp->b_flags |= B_INVAL;
+ break;
+ default:
+ printf(" nfs_bioread: type %x unexpected\n",vp->v_type);
+ }
+ brelse(bp);
+ } while (error == 0 && uio->uio_resid > 0 && n > 0);
+ return (error);
+}
+
+/*
+ * Vnode op for write using bio
+ */
+int
+nfs_write(ap)
+ struct vop_write_args /* {
+ struct vnode *a_vp;
+ struct uio *a_uio;
+ int a_ioflag;
+ struct ucred *a_cred;
+ } */ *ap;
+{
+ int biosize;
+ struct uio *uio = ap->a_uio;
+ struct proc *p = uio->uio_procp;
+ struct vnode *vp = ap->a_vp;
+ struct nfsnode *np = VTONFS(vp);
+ struct ucred *cred = ap->a_cred;
+ int ioflag = ap->a_ioflag;
+ struct buf *bp;
+ struct vattr vattr;
+ struct nfsmount *nmp = VFSTONFS(vp->v_mount);
+ daddr_t lbn;
+ int bcount;
+ int n, on, error = 0, iomode, must_commit;
+ int haverslock = 0;
+
+#ifdef DIAGNOSTIC
+ if (uio->uio_rw != UIO_WRITE)
+ panic("nfs_write mode");
+ if (uio->uio_segflg == UIO_USERSPACE && uio->uio_procp != curproc)
+ panic("nfs_write proc");
+#endif
+ if (vp->v_type != VREG)
+ return (EIO);
+ if (np->n_flag & NWRITEERR) {
+ np->n_flag &= ~NWRITEERR;
+ return (np->n_error);
+ }
+ if ((nmp->nm_flag & NFSMNT_NFSV3) != 0 &&
+ (nmp->nm_state & NFSSTA_GOTFSINFO) == 0)
+ (void)nfs_fsinfo(nmp, vp, cred, p);
+
+ /*
+ * Synchronously flush pending buffers if we are in synchronous
+ * mode or if we are appending.
+ */
+ if (ioflag & (IO_APPEND | IO_SYNC)) {
+ if (np->n_flag & NMODIFIED) {
+ np->n_attrstamp = 0;
+ error = nfs_vinvalbuf(vp, V_SAVE, cred, p, 1);
+ if (error)
+ return (error);
+ }
+ }
+
+ /*
+ * If IO_APPEND then load uio_offset. We restart here if we cannot
+ * get the append lock.
+ */
+restart:
+ if (ioflag & IO_APPEND) {
+ np->n_attrstamp = 0;
+ error = VOP_GETATTR(vp, &vattr, cred, p);
+ if (error)
+ return (error);
+ uio->uio_offset = np->n_size;
+ }
+
+ if (uio->uio_offset < 0)
+ return (EINVAL);
+ if ((uio->uio_offset + uio->uio_resid) > nmp->nm_maxfilesize)
+ return (EFBIG);
+ if (uio->uio_resid == 0)
+ return (0);
+
+ /*
+ * We need to obtain the rslock if we intend to modify np->n_size
+ * in order to guarentee the append point with multiple contending
+ * writers, to guarentee that no other appenders modify n_size
+ * while we are trying to obtain a truncated buffer (i.e. to avoid
+ * accidently truncating data written by another appender due to
+ * the race), and to ensure that the buffer is populated prior to
+ * our extending of the file. We hold rslock through the entire
+ * operation.
+ *
+ * Note that we do not synchronize the case where someone truncates
+ * the file while we are appending to it because attempting to lock
+ * this case may deadlock other parts of the system unexpectedly.
+ */
+ if ((ioflag & IO_APPEND) ||
+ uio->uio_offset + uio->uio_resid > np->n_size) {
+ if (nfs_rslock(np, p) == ENOLCK)
+ goto restart;
+ haverslock = 1;
+ }
+
+ /*
+ * Maybe this should be above the vnode op call, but so long as
+ * file servers have no limits, i don't think it matters
+ */
+ if (p && uio->uio_offset + uio->uio_resid >
+ p->p_rlimit[RLIMIT_FSIZE].rlim_cur) {
+ psignal(p, SIGXFSZ);
+ if (haverslock)
+ nfs_rsunlock(np, p);
+ return (EFBIG);
+ }
+
+ biosize = vp->v_mount->mnt_stat.f_iosize;
+
+ do {
+ /*
+ * Check for a valid write lease.
+ */
+ if ((nmp->nm_flag & NFSMNT_NQNFS) &&
+ NQNFS_CKINVALID(vp, np, ND_WRITE)) {
+ do {
+ error = nqnfs_getlease(vp, ND_WRITE, cred, p);
+ } while (error == NQNFS_EXPIRED);
+ if (error)
+ break;
+ if (np->n_lrev != np->n_brev ||
+ (np->n_flag & NQNFSNONCACHE)) {
+ error = nfs_vinvalbuf(vp, V_SAVE, cred, p, 1);
+ if (error)
+ break;
+ np->n_brev = np->n_lrev;
+ }
+ }
+ if ((np->n_flag & NQNFSNONCACHE) && uio->uio_iovcnt == 1) {
+ iomode = NFSV3WRITE_FILESYNC;
+ error = nfs_writerpc(vp, uio, cred, &iomode, &must_commit);
+ if (must_commit)
+ nfs_clearcommit(vp->v_mount);
+ break;
+ }
+ nfsstats.biocache_writes++;
+ lbn = uio->uio_offset / biosize;
+ on = uio->uio_offset & (biosize-1);
+ n = min((unsigned)(biosize - on), uio->uio_resid);
+again:
+ /*
+ * Handle direct append and file extension cases, calculate
+ * unaligned buffer size.
+ */
+
+ if (uio->uio_offset == np->n_size && n) {
+ /*
+ * Get the buffer (in its pre-append state to maintain
+ * B_CACHE if it was previously set). Resize the
+ * nfsnode after we have locked the buffer to prevent
+ * readers from reading garbage.
+ */
+ bcount = on;
+ bp = nfs_getcacheblk(vp, lbn, bcount, p);
+
+ if (bp != NULL) {
+ long save;
+
+ np->n_size = uio->uio_offset + n;
+ np->n_flag |= NMODIFIED;
+ vnode_pager_setsize(vp, np->n_size);
+
+ save = bp->b_flags & B_CACHE;
+ bcount += n;
+ allocbuf(bp, bcount);
+ bp->b_flags |= save;
+ }
+ } else {
+ /*
+ * Obtain the locked cache block first, and then
+ * adjust the file's size as appropriate.
+ */
+ bcount = on + n;
+ if ((off_t)lbn * biosize + bcount < np->n_size) {
+ if ((off_t)(lbn + 1) * biosize < np->n_size)
+ bcount = biosize;
+ else
+ bcount = np->n_size - (off_t)lbn * biosize;
+ }
+
+ bp = nfs_getcacheblk(vp, lbn, bcount, p);
+
+ if (uio->uio_offset + n > np->n_size) {
+ np->n_size = uio->uio_offset + n;
+ np->n_flag |= NMODIFIED;
+ vnode_pager_setsize(vp, np->n_size);
+ }
+ }
+
+ if (!bp) {
+ error = EINTR;
+ break;
+ }
+
+ /*
+ * Issue a READ if B_CACHE is not set. In special-append
+ * mode, B_CACHE is based on the buffer prior to the write
+ * op and is typically set, avoiding the read. If a read
+ * is required in special append mode, the server will
+ * probably send us a short-read since we extended the file
+ * on our end, resulting in b_resid == 0 and, thusly,
+ * B_CACHE getting set.
+ *
+ * We can also avoid issuing the read if the write covers
+ * the entire buffer. We have to make sure the buffer state
+ * is reasonable in this case since we will not be initiating
+ * I/O. See the comments in kern/vfs_bio.c's getblk() for
+ * more information.
+ *
+ * B_CACHE may also be set due to the buffer being cached
+ * normally.
+ */
+
+ if (on == 0 && n == bcount) {
+ bp->b_flags |= B_CACHE;
+ bp->b_flags &= ~(B_ERROR | B_INVAL);
+ }
+
+ if ((bp->b_flags & B_CACHE) == 0) {
+ bp->b_flags |= B_READ;
+ vfs_busy_pages(bp, 0);
+ error = nfs_doio(bp, cred, p);
+ if (error) {
+ brelse(bp);
+ break;
+ }
+ }
+ if (!bp) {
+ error = EINTR;
+ break;
+ }
+ if (bp->b_wcred == NOCRED) {
+ crhold(cred);
+ bp->b_wcred = cred;
+ }
+ np->n_flag |= NMODIFIED;
+
+ /*
+ * If dirtyend exceeds file size, chop it down. This should
+ * not normally occur but there is an append race where it
+ * might occur XXX, so we log it.
+ *
+ * If the chopping creates a reverse-indexed or degenerate
+ * situation with dirtyoff/end, we 0 both of them.
+ */
+
+ if (bp->b_dirtyend > bcount) {
+ printf("NFS append race @%lx:%d\n",
+ (long)bp->b_blkno * DEV_BSIZE,
+ bp->b_dirtyend - bcount);
+ bp->b_dirtyend = bcount;
+ }
+
+ if (bp->b_dirtyoff >= bp->b_dirtyend)
+ bp->b_dirtyoff = bp->b_dirtyend = 0;
+
+ /*
+ * If the new write will leave a contiguous dirty
+ * area, just update the b_dirtyoff and b_dirtyend,
+ * otherwise force a write rpc of the old dirty area.
+ *
+ * While it is possible to merge discontiguous writes due to
+ * our having a B_CACHE buffer ( and thus valid read data
+ * for the hole), we don't because it could lead to
+ * significant cache coherency problems with multiple clients,
+ * especially if locking is implemented later on.
+ *
+ * as an optimization we could theoretically maintain
+ * a linked list of discontinuous areas, but we would still
+ * have to commit them separately so there isn't much
+ * advantage to it except perhaps a bit of asynchronization.
+ */
+
+ if (bp->b_dirtyend > 0 &&
+ (on > bp->b_dirtyend || (on + n) < bp->b_dirtyoff)) {
+ if (VOP_BWRITE(bp->b_vp, bp) == EINTR)
+ return (EINTR);
+ goto again;
+ }
+
+ /*
+ * Check for valid write lease and get one as required.
+ * In case getblk() and/or bwrite() delayed us.
+ */
+ if ((nmp->nm_flag & NFSMNT_NQNFS) &&
+ NQNFS_CKINVALID(vp, np, ND_WRITE)) {
+ do {
+ error = nqnfs_getlease(vp, ND_WRITE, cred, p);
+ } while (error == NQNFS_EXPIRED);
+ if (error) {
+ brelse(bp);
+ break;
+ }
+ if (np->n_lrev != np->n_brev ||
+ (np->n_flag & NQNFSNONCACHE)) {
+ brelse(bp);
+ error = nfs_vinvalbuf(vp, V_SAVE, cred, p, 1);
+ if (error)
+ break;
+ np->n_brev = np->n_lrev;
+ goto again;
+ }
+ }
+
+ error = uiomove((char *)bp->b_data + on, n, uio);
+
+ /*
+ * Since this block is being modified, it must be written
+ * again and not just committed. Since write clustering does
+ * not work for the stage 1 data write, only the stage 2
+ * commit rpc, we have to clear B_CLUSTEROK as well.
+ */
+ bp->b_flags &= ~(B_NEEDCOMMIT | B_CLUSTEROK);
+
+ if (error) {
+ bp->b_flags |= B_ERROR;
+ brelse(bp);
+ break;
+ }
+
+ /*
+ * Only update dirtyoff/dirtyend if not a degenerate
+ * condition.
+ */
+ if (n) {
+ if (bp->b_dirtyend > 0) {
+ bp->b_dirtyoff = min(on, bp->b_dirtyoff);
+ bp->b_dirtyend = max((on + n), bp->b_dirtyend);
+ } else {
+ bp->b_dirtyoff = on;
+ bp->b_dirtyend = on + n;
+ }
+ vfs_bio_set_validclean(bp, on, n);
+ }
+
+ /*
+ * If the lease is non-cachable or IO_SYNC do bwrite().
+ *
+ * IO_INVAL appears to be unused. The idea appears to be
+ * to turn off caching in this case. Very odd. XXX
+ */
+ if ((np->n_flag & NQNFSNONCACHE) || (ioflag & IO_SYNC)) {
+ if (ioflag & IO_INVAL)
+ bp->b_flags |= B_NOCACHE;
+ error = VOP_BWRITE(bp->b_vp, bp);
+ if (error)
+ break;
+ if (np->n_flag & NQNFSNONCACHE) {
+ error = nfs_vinvalbuf(vp, V_SAVE, cred, p, 1);
+ if (error)
+ break;
+ }
+ } else if ((n + on) == biosize &&
+ (nmp->nm_flag & NFSMNT_NQNFS) == 0) {
+ bp->b_flags |= B_ASYNC;
+ (void)nfs_writebp(bp, 0, 0);
+ } else {
+ bdwrite(bp);
+ }
+ } while (uio->uio_resid > 0 && n > 0);
+
+ if (haverslock)
+ nfs_rsunlock(np, p);
+
+ return (error);
+}
+
+/*
+ * Get an nfs cache block.
+ *
+ * Allocate a new one if the block isn't currently in the cache
+ * and return the block marked busy. If the calling process is
+ * interrupted by a signal for an interruptible mount point, return
+ * NULL.
+ *
+ * The caller must carefully deal with the possible B_INVAL state of
+ * the buffer. nfs_doio() clears B_INVAL (and nfs_asyncio() clears it
+ * indirectly), so synchronous reads can be issued without worrying about
+ * the B_INVAL state. We have to be a little more careful when dealing
+ * with writes (see comments in nfs_write()) when extending a file past
+ * its EOF.
+ */
+static struct buf *
+nfs_getcacheblk(vp, bn, size, p)
+ struct vnode *vp;
+ daddr_t bn;
+ int size;
+ struct proc *p;
+{
+ register struct buf *bp;
+ struct mount *mp;
+ struct nfsmount *nmp;
+
+ mp = vp->v_mount;
+ nmp = VFSTONFS(mp);
+
+ if (nmp->nm_flag & NFSMNT_INT) {
+ bp = getblk(vp, bn, size, PCATCH, 0);
+ while (bp == (struct buf *)0) {
+ if (nfs_sigintr(nmp, (struct nfsreq *)0, p))
+ return ((struct buf *)0);
+ bp = getblk(vp, bn, size, 0, 2 * hz);
+ }
+ } else {
+ bp = getblk(vp, bn, size, 0, 0);
+ }
+
+ if (vp->v_type == VREG) {
+ int biosize;
+
+ biosize = mp->mnt_stat.f_iosize;
+ bp->b_blkno = bn * (biosize / DEV_BSIZE);
+ }
+ return (bp);
+}
+
+/*
+ * Flush and invalidate all dirty buffers. If another process is already
+ * doing the flush, just wait for completion.
+ */
+int
+nfs_vinvalbuf(vp, flags, cred, p, intrflg)
+ struct vnode *vp;
+ int flags;
+ struct ucred *cred;
+ struct proc *p;
+ int intrflg;
+{
+ register struct nfsnode *np = VTONFS(vp);
+ struct nfsmount *nmp = VFSTONFS(vp->v_mount);
+ int error = 0, slpflag, slptimeo;
+
+ if (vp->v_flag & VXLOCK) {
+ return (0);
+ }
+
+ if ((nmp->nm_flag & NFSMNT_INT) == 0)
+ intrflg = 0;
+ if (intrflg) {
+ slpflag = PCATCH;
+ slptimeo = 2 * hz;
+ } else {
+ slpflag = 0;
+ slptimeo = 0;
+ }
+ /*
+ * First wait for any other process doing a flush to complete.
+ */
+ while (np->n_flag & NFLUSHINPROG) {
+ np->n_flag |= NFLUSHWANT;
+ error = tsleep((caddr_t)&np->n_flag, PRIBIO + 2, "nfsvinval",
+ slptimeo);
+ if (error && intrflg && nfs_sigintr(nmp, (struct nfsreq *)0, p))
+ return (EINTR);
+ }
+
+ /*
+ * Now, flush as required.
+ */
+ np->n_flag |= NFLUSHINPROG;
+ error = vinvalbuf(vp, flags, cred, p, slpflag, 0);
+ while (error) {
+ if (intrflg && nfs_sigintr(nmp, (struct nfsreq *)0, p)) {
+ np->n_flag &= ~NFLUSHINPROG;
+ if (np->n_flag & NFLUSHWANT) {
+ np->n_flag &= ~NFLUSHWANT;
+ wakeup((caddr_t)&np->n_flag);
+ }
+ return (EINTR);
+ }
+ error = vinvalbuf(vp, flags, cred, p, 0, slptimeo);
+ }
+ np->n_flag &= ~(NMODIFIED | NFLUSHINPROG);
+ if (np->n_flag & NFLUSHWANT) {
+ np->n_flag &= ~NFLUSHWANT;
+ wakeup((caddr_t)&np->n_flag);
+ }
+ return (0);
+}
+
+/*
+ * Initiate asynchronous I/O. Return an error if no nfsiods are available.
+ * This is mainly to avoid queueing async I/O requests when the nfsiods
+ * are all hung on a dead server.
+ *
+ * Note: nfs_asyncio() does not clear (B_ERROR|B_INVAL) but when the bp
+ * is eventually dequeued by the async daemon, nfs_doio() *will*.
+ */
+int
+nfs_asyncio(bp, cred, procp)
+ register struct buf *bp;
+ struct ucred *cred;
+ struct proc *procp;
+{
+ struct nfsmount *nmp;
+ int i;
+ int gotiod;
+ int slpflag = 0;
+ int slptimeo = 0;
+ int error;
+
+ if (nfs_numasync == 0)
+ return (EIO);
+
+ nmp = VFSTONFS(bp->b_vp->v_mount);
+again:
+ if (nmp->nm_flag & NFSMNT_INT)
+ slpflag = PCATCH;
+ gotiod = FALSE;
+
+ /*
+ * Find a free iod to process this request.
+ */
+ for (i = 0; i < NFS_MAXASYNCDAEMON; i++)
+ if (nfs_iodwant[i]) {
+ /*
+ * Found one, so wake it up and tell it which
+ * mount to process.
+ */
+ NFS_DPF(ASYNCIO,
+ ("nfs_asyncio: waking iod %d for mount %p\n",
+ i, nmp));
+ nfs_iodwant[i] = (struct proc *)0;
+ nfs_iodmount[i] = nmp;
+ nmp->nm_bufqiods++;
+ wakeup((caddr_t)&nfs_iodwant[i]);
+ gotiod = TRUE;
+ break;
+ }
+
+ /*
+ * If none are free, we may already have an iod working on this mount
+ * point. If so, it will process our request.
+ */
+ if (!gotiod) {
+ if (nmp->nm_bufqiods > 0) {
+ NFS_DPF(ASYNCIO,
+ ("nfs_asyncio: %d iods are already processing mount %p\n",
+ nmp->nm_bufqiods, nmp));
+ gotiod = TRUE;
+ }
+ }
+
+ /*
+ * If we have an iod which can process the request, then queue
+ * the buffer.
+ */
+ if (gotiod) {
+ /*
+ * Ensure that the queue never grows too large.
+ */
+ while (nmp->nm_bufqlen >= 2*nfs_numasync) {
+ NFS_DPF(ASYNCIO,
+ ("nfs_asyncio: waiting for mount %p queue to drain\n", nmp));
+ nmp->nm_bufqwant = TRUE;
+ error = tsleep(&nmp->nm_bufq, slpflag | PRIBIO,
+ "nfsaio", slptimeo);
+ if (error) {
+ if (nfs_sigintr(nmp, NULL, procp))
+ return (EINTR);
+ if (slpflag == PCATCH) {
+ slpflag = 0;
+ slptimeo = 2 * hz;
+ }
+ }
+ /*
+ * We might have lost our iod while sleeping,
+ * so check and loop if nescessary.
+ */
+ if (nmp->nm_bufqiods == 0) {
+ NFS_DPF(ASYNCIO,
+ ("nfs_asyncio: no iods after mount %p queue was drained, looping\n", nmp));
+ goto again;
+ }
+ }
+
+ if (bp->b_flags & B_READ) {
+ if (bp->b_rcred == NOCRED && cred != NOCRED) {
+ crhold(cred);
+ bp->b_rcred = cred;
+ }
+ } else {
+ bp->b_flags |= B_WRITEINPROG;
+ if (bp->b_wcred == NOCRED && cred != NOCRED) {
+ crhold(cred);
+ bp->b_wcred = cred;
+ }
+ }
+
+ BUF_KERNPROC(bp);
+ TAILQ_INSERT_TAIL(&nmp->nm_bufq, bp, b_freelist);
+ nmp->nm_bufqlen++;
+ return (0);
+ }
+
+ /*
+ * All the iods are busy on other mounts, so return EIO to
+ * force the caller to process the i/o synchronously.
+ */
+ NFS_DPF(ASYNCIO, ("nfs_asyncio: no iods available, i/o is synchronous\n"));
+ return (EIO);
+}
+
+/*
+ * Do an I/O operation to/from a cache block. This may be called
+ * synchronously or from an nfsiod.
+ */
+int
+nfs_doio(bp, cr, p)
+ struct buf *bp;
+ struct ucred *cr;
+ struct proc *p;
+{
+ struct uio *uiop;
+ struct vnode *vp;
+ struct nfsnode *np;
+ struct nfsmount *nmp;
+ int error = 0, iomode, must_commit = 0;
+ struct uio uio;
+ struct iovec io;
+
+ vp = bp->b_vp;
+ np = VTONFS(vp);
+ nmp = VFSTONFS(vp->v_mount);
+ uiop = &uio;
+ uiop->uio_iov = &io;
+ uiop->uio_iovcnt = 1;
+ uiop->uio_segflg = UIO_SYSSPACE;
+ uiop->uio_procp = p;
+
+ /*
+ * clear B_ERROR and B_INVAL state prior to initiating the I/O. We
+ * do this here so we do not have to do it in all the code that
+ * calls us.
+ */
+ bp->b_flags &= ~(B_ERROR | B_INVAL);
+
+ KASSERT(!(bp->b_flags & B_DONE), ("nfs_doio: bp %p already marked done", bp));
+
+ /*
+ * Historically, paging was done with physio, but no more.
+ */
+ if (bp->b_flags & B_PHYS) {
+ /*
+ * ...though reading /dev/drum still gets us here.
+ */
+ io.iov_len = uiop->uio_resid = bp->b_bcount;
+ /* mapping was done by vmapbuf() */
+ io.iov_base = bp->b_data;
+ uiop->uio_offset = ((off_t)bp->b_blkno) * DEV_BSIZE;
+ if (bp->b_flags & B_READ) {
+ uiop->uio_rw = UIO_READ;
+ nfsstats.read_physios++;
+ error = nfs_readrpc(vp, uiop, cr);
+ } else {
+ int com;
+
+ iomode = NFSV3WRITE_DATASYNC;
+ uiop->uio_rw = UIO_WRITE;
+ nfsstats.write_physios++;
+ error = nfs_writerpc(vp, uiop, cr, &iomode, &com);
+ }
+ if (error) {
+ bp->b_flags |= B_ERROR;
+ bp->b_error = error;
+ }
+ } else if (bp->b_flags & B_READ) {
+ io.iov_len = uiop->uio_resid = bp->b_bcount;
+ io.iov_base = bp->b_data;
+ uiop->uio_rw = UIO_READ;
+ switch (vp->v_type) {
+ case VREG:
+ uiop->uio_offset = ((off_t)bp->b_blkno) * DEV_BSIZE;
+ nfsstats.read_bios++;
+ error = nfs_readrpc(vp, uiop, cr);
+ if (!error) {
+ if (uiop->uio_resid) {
+ /*
+ * If we had a short read with no error, we must have
+ * hit a file hole. We should zero-fill the remainder.
+ * This can also occur if the server hits the file EOF.
+ *
+ * Holes used to be able to occur due to pending
+ * writes, but that is not possible any longer.
+ */
+ int nread = bp->b_bcount - uiop->uio_resid;
+ int left = bp->b_bcount - nread;
+
+ if (left > 0)
+ bzero((char *)bp->b_data + nread, left);
+ uiop->uio_resid = 0;
+ }
+ }
+ if (p && (vp->v_flag & VTEXT) &&
+ (((nmp->nm_flag & NFSMNT_NQNFS) &&
+ NQNFS_CKINVALID(vp, np, ND_READ) &&
+ np->n_lrev != np->n_brev) ||
+ (!(nmp->nm_flag & NFSMNT_NQNFS) &&
+ np->n_mtime != np->n_vattr.va_mtime.tv_sec))) {
+ uprintf("Process killed due to text file modification\n");
+ psignal(p, SIGKILL);
+ PHOLD(p);
+ }
+ break;
+ case VLNK:
+ uiop->uio_offset = (off_t)0;
+ nfsstats.readlink_bios++;
+ error = nfs_readlinkrpc(vp, uiop, cr);
+ break;
+ case VDIR:
+ nfsstats.readdir_bios++;
+ uiop->uio_offset = ((u_quad_t)bp->b_lblkno) * NFS_DIRBLKSIZ;
+ if (nmp->nm_flag & NFSMNT_RDIRPLUS) {
+ error = nfs_readdirplusrpc(vp, uiop, cr);
+ if (error == NFSERR_NOTSUPP)
+ nmp->nm_flag &= ~NFSMNT_RDIRPLUS;
+ }
+ if ((nmp->nm_flag & NFSMNT_RDIRPLUS) == 0)
+ error = nfs_readdirrpc(vp, uiop, cr);
+ /*
+ * end-of-directory sets B_INVAL but does not generate an
+ * error.
+ */
+ if (error == 0 && uiop->uio_resid == bp->b_bcount)
+ bp->b_flags |= B_INVAL;
+ break;
+ default:
+ printf("nfs_doio: type %x unexpected\n",vp->v_type);
+ break;
+ };
+ if (error) {
+ bp->b_flags |= B_ERROR;
+ bp->b_error = error;
+ }
+ } else {
+ /*
+ * If we only need to commit, try to commit
+ */
+ if (bp->b_flags & B_NEEDCOMMIT) {
+ int retv;
+ off_t off;
+
+ off = ((u_quad_t)bp->b_blkno) * DEV_BSIZE + bp->b_dirtyoff;
+ bp->b_flags |= B_WRITEINPROG;
+ retv = nfs_commit(
+ bp->b_vp, off, bp->b_dirtyend-bp->b_dirtyoff,
+ bp->b_wcred, p);
+ bp->b_flags &= ~B_WRITEINPROG;
+ if (retv == 0) {
+ bp->b_dirtyoff = bp->b_dirtyend = 0;
+ bp->b_flags &= ~(B_NEEDCOMMIT | B_CLUSTEROK);
+ bp->b_resid = 0;
+ biodone(bp);
+ return (0);
+ }
+ if (retv == NFSERR_STALEWRITEVERF) {
+ nfs_clearcommit(bp->b_vp->v_mount);
+ }
+ }
+
+ /*
+ * Setup for actual write
+ */
+
+ if ((off_t)bp->b_blkno * DEV_BSIZE + bp->b_dirtyend > np->n_size)
+ bp->b_dirtyend = np->n_size - (off_t)bp->b_blkno * DEV_BSIZE;
+
+ if (bp->b_dirtyend > bp->b_dirtyoff) {
+ io.iov_len = uiop->uio_resid = bp->b_dirtyend
+ - bp->b_dirtyoff;
+ uiop->uio_offset = (off_t)bp->b_blkno * DEV_BSIZE
+ + bp->b_dirtyoff;
+ io.iov_base = (char *)bp->b_data + bp->b_dirtyoff;
+ uiop->uio_rw = UIO_WRITE;
+ nfsstats.write_bios++;
+
+ if ((bp->b_flags & (B_ASYNC | B_NEEDCOMMIT | B_NOCACHE | B_CLUSTER)) == B_ASYNC)
+ iomode = NFSV3WRITE_UNSTABLE;
+ else
+ iomode = NFSV3WRITE_FILESYNC;
+
+ bp->b_flags |= B_WRITEINPROG;
+ error = nfs_writerpc(vp, uiop, cr, &iomode, &must_commit);
+
+ /*
+ * When setting B_NEEDCOMMIT also set B_CLUSTEROK to try
+ * to cluster the buffers needing commit. This will allow
+ * the system to submit a single commit rpc for the whole
+ * cluster. We can do this even if the buffer is not 100%
+ * dirty (relative to the NFS blocksize), so we optimize the
+ * append-to-file-case.
+ *
+ * (when clearing B_NEEDCOMMIT, B_CLUSTEROK must also be
+ * cleared because write clustering only works for commit
+ * rpc's, not for the data portion of the write).
+ */
+
+ if (!error && iomode == NFSV3WRITE_UNSTABLE) {
+ bp->b_flags |= B_NEEDCOMMIT;
+ if (bp->b_dirtyoff == 0
+ && bp->b_dirtyend == bp->b_bcount)
+ bp->b_flags |= B_CLUSTEROK;
+ } else {
+ bp->b_flags &= ~(B_NEEDCOMMIT | B_CLUSTEROK);
+ }
+ bp->b_flags &= ~B_WRITEINPROG;
+
+ /*
+ * For an interrupted write, the buffer is still valid
+ * and the write hasn't been pushed to the server yet,
+ * so we can't set B_ERROR and report the interruption
+ * by setting B_EINTR. For the B_ASYNC case, B_EINTR
+ * is not relevant, so the rpc attempt is essentially
+ * a noop. For the case of a V3 write rpc not being
+ * committed to stable storage, the block is still
+ * dirty and requires either a commit rpc or another
+ * write rpc with iomode == NFSV3WRITE_FILESYNC before
+ * the block is reused. This is indicated by setting
+ * the B_DELWRI and B_NEEDCOMMIT flags.
+ *
+ * If the buffer is marked B_PAGING, it does not reside on
+ * the vp's paging queues so we cannot call bdirty(). The
+ * bp in this case is not an NFS cache block so we should
+ * be safe. XXX
+ */
+ if (error == EINTR
+ || (!error && (bp->b_flags & B_NEEDCOMMIT))) {
+ int s;
+
+ s = splbio();
+ bp->b_flags &= ~(B_INVAL|B_NOCACHE);
+ if ((bp->b_flags & B_PAGING) == 0) {
+ bdirty(bp);
+ bp->b_flags &= ~B_DONE;
+ }
+ if (error && (bp->b_flags & B_ASYNC) == 0)
+ bp->b_flags |= B_EINTR;
+ splx(s);
+ } else {
+ if (error) {
+ bp->b_flags |= B_ERROR;
+ bp->b_error = np->n_error = error;
+ np->n_flag |= NWRITEERR;
+ }
+ bp->b_dirtyoff = bp->b_dirtyend = 0;
+ }
+ } else {
+ bp->b_resid = 0;
+ biodone(bp);
+ return (0);
+ }
+ }
+ bp->b_resid = uiop->uio_resid;
+ if (must_commit)
+ nfs_clearcommit(vp->v_mount);
+ biodone(bp);
+ return (error);
+}
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