/*- * 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_bio.c 8.9 (Berkeley) 3/30/95 */ #include __FBSDID("$FreeBSD$"); #include "opt_kdtrace.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include static struct buf *nfs_getcacheblk(struct vnode *vp, daddr_t bn, int size, struct thread *td); static int nfs_directio_write(struct vnode *vp, struct uio *uiop, struct ucred *cred, int ioflag); extern int nfs_directio_enable; extern int nfs_directio_allow_mmap; /* * Vnode op for VM getpages. */ int nfs_getpages(struct vop_getpages_args *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 thread *td; struct ucred *cred; struct nfsmount *nmp; vm_object_t object; vm_page_t *pages; struct nfsnode *np; vp = ap->a_vp; np = VTONFS(vp); td = curthread; /* XXX */ cred = curthread->td_ucred; /* XXX */ nmp = VFSTONFS(vp->v_mount); pages = ap->a_m; count = ap->a_count; if ((object = vp->v_object) == NULL) { nfs_printf("nfs_getpages: called with non-merged cache vnode??\n"); return (VM_PAGER_ERROR); } if (nfs_directio_enable && !nfs_directio_allow_mmap) { mtx_lock(&np->n_mtx); if ((np->n_flag & NNONCACHE) && (vp->v_type == VREG)) { mtx_unlock(&np->n_mtx); nfs_printf("nfs_getpages: called on non-cacheable vnode??\n"); return (VM_PAGER_ERROR); } else mtx_unlock(&np->n_mtx); } mtx_lock(&nmp->nm_mtx); if ((nmp->nm_flag & NFSMNT_NFSV3) != 0 && (nmp->nm_state & NFSSTA_GOTFSINFO) == 0) { mtx_unlock(&nmp->nm_mtx); /* We'll never get here for v4, because we always have fsinfo */ (void)nfs_fsinfo(nmp, vp, cred, td); } else mtx_unlock(&nmp->nm_mtx); 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_OBJECT_WLOCK(object); if (pages[ap->a_reqpage]->valid != 0) { for (i = 0; i < npages; ++i) { if (i != ap->a_reqpage) { vm_page_lock(pages[i]); vm_page_free(pages[i]); vm_page_unlock(pages[i]); } } VM_OBJECT_WUNLOCK(object); return (0); } VM_OBJECT_WUNLOCK(object); /* * 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); PCPU_INC(cnt.v_vnodein); PCPU_ADD(cnt.v_vnodepgsin, 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_td = td; error = (nmp->nm_rpcops->nr_readrpc)(vp, &uio, cred); pmap_qremove(kva, npages); relpbuf(bp, &nfs_pbuf_freecnt); if (error && (uio.uio_resid == count)) { nfs_printf("nfs_getpages: error %d\n", error); VM_OBJECT_WLOCK(object); for (i = 0; i < npages; ++i) { if (i != ap->a_reqpage) { vm_page_lock(pages[i]); vm_page_free(pages[i]); vm_page_unlock(pages[i]); } } VM_OBJECT_WUNLOCK(object); 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; VM_OBJECT_WLOCK(object); for (i = 0, toff = 0; i < npages; i++, toff = nextoff) { vm_page_t m; nextoff = toff + PAGE_SIZE; m = pages[i]; if (nextoff <= size) { /* * Read operation filled an entire page */ m->valid = VM_PAGE_BITS_ALL; KASSERT(m->dirty == 0, ("nfs_getpages: page %p is dirty", m)); } else if (size > toff) { /* * Read operation filled a partial page. */ m->valid = 0; vm_page_set_valid_range(m, 0, size - toff); KASSERT(m->dirty == 0, ("nfs_getpages: page %p is dirty", m)); } else { /* * Read operation was short. If no error * occured we may have hit a zero-fill * section. We leave valid set to 0, and page * is freed by vm_page_readahead_finish() if * its index is not equal to requested, or * page is zeroed and set valid by * vm_pager_get_pages() for requested page. */ ; } if (i != ap->a_reqpage) vm_page_readahead_finish(m); } VM_OBJECT_WUNLOCK(object); return (0); } /* * Vnode op for VM putpages. */ int nfs_putpages(struct vop_putpages_args *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 thread *td; struct ucred *cred; struct nfsmount *nmp; struct nfsnode *np; vm_page_t *pages; vp = ap->a_vp; np = VTONFS(vp); td = curthread; /* XXX */ /* Set the cred to n_writecred for the write rpcs. */ if (np->n_writecred != NULL) cred = crhold(np->n_writecred); else cred = crhold(curthread->td_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); mtx_lock(&nmp->nm_mtx); if ((nmp->nm_flag & NFSMNT_NFSV3) != 0 && (nmp->nm_state & NFSSTA_GOTFSINFO) == 0) { mtx_unlock(&nmp->nm_mtx); (void)nfs_fsinfo(nmp, vp, cred, td); } else mtx_unlock(&nmp->nm_mtx); mtx_lock(&np->n_mtx); if (nfs_directio_enable && !nfs_directio_allow_mmap && (np->n_flag & NNONCACHE) && (vp->v_type == VREG)) { mtx_unlock(&np->n_mtx); nfs_printf("nfs_putpages: called on noncache-able vnode??\n"); mtx_lock(&np->n_mtx); } for (i = 0; i < npages; i++) rtvals[i] = VM_PAGER_ERROR; /* * 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; } mtx_unlock(&np->n_mtx); /* * 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); PCPU_INC(cnt.v_vnodeout); PCPU_ADD(cnt.v_vnodepgsout, count); 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_td = td; if ((ap->a_sync & VM_PAGER_PUT_SYNC) == 0) iomode = NFSV3WRITE_UNSTABLE; else iomode = NFSV3WRITE_FILESYNC; error = (nmp->nm_rpcops->nr_writerpc)(vp, &uio, cred, &iomode, &must_commit); crfree(cred); pmap_qremove(kva, npages); relpbuf(bp, &nfs_pbuf_freecnt); if (!error) { vnode_pager_undirty_pages(pages, rtvals, count - uio.uio_resid); if (must_commit) { nfs_clearcommit(vp->v_mount); } } return rtvals[0]; } /* * 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 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. */ static inline int nfs_bioread_check_cons(struct vnode *vp, struct thread *td, struct ucred *cred) { int error = 0; struct vattr vattr; struct nfsnode *np = VTONFS(vp); int old_lock; struct nfsmount *nmp = VFSTONFS(vp->v_mount); /* * Grab the exclusive lock before checking whether the cache is * consistent. * XXX - We can make this cheaper later (by acquiring cheaper locks). * But for now, this suffices. */ old_lock = nfs_upgrade_vnlock(vp); if (vp->v_iflag & VI_DOOMED) { nfs_downgrade_vnlock(vp, old_lock); return (EBADF); } mtx_lock(&np->n_mtx); if (np->n_flag & NMODIFIED) { mtx_unlock(&np->n_mtx); if (vp->v_type != VREG) { if (vp->v_type != VDIR) panic("nfs: bioread, not dir"); (nmp->nm_rpcops->nr_invaldir)(vp); error = nfs_vinvalbuf(vp, V_SAVE, td, 1); if (error) goto out; } np->n_attrstamp = 0; KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(vp); error = VOP_GETATTR(vp, &vattr, cred); if (error) goto out; mtx_lock(&np->n_mtx); np->n_mtime = vattr.va_mtime; mtx_unlock(&np->n_mtx); } else { mtx_unlock(&np->n_mtx); error = VOP_GETATTR(vp, &vattr, cred); if (error) return (error); mtx_lock(&np->n_mtx); if ((np->n_flag & NSIZECHANGED) || (NFS_TIMESPEC_COMPARE(&np->n_mtime, &vattr.va_mtime))) { mtx_unlock(&np->n_mtx); if (vp->v_type == VDIR) (nmp->nm_rpcops->nr_invaldir)(vp); error = nfs_vinvalbuf(vp, V_SAVE, td, 1); if (error) goto out; mtx_lock(&np->n_mtx); np->n_mtime = vattr.va_mtime; np->n_flag &= ~NSIZECHANGED; } mtx_unlock(&np->n_mtx); } out: nfs_downgrade_vnlock(vp, old_lock); return error; } /* * Vnode op for read using bio */ int nfs_bioread(struct vnode *vp, struct uio *uio, int ioflag, struct ucred *cred) { struct nfsnode *np = VTONFS(vp); int biosize, i; struct buf *bp, *rabp; struct thread *td; struct nfsmount *nmp = VFSTONFS(vp->v_mount); daddr_t lbn, rabn; off_t end; int bcount; int seqcount; int nra, error = 0, n = 0, on = 0; KASSERT(uio->uio_rw == UIO_READ, ("nfs_read mode")); if (uio->uio_resid == 0) return (0); if (uio->uio_offset < 0) /* XXX VDIR cookies can be negative */ return (EINVAL); td = uio->uio_td; mtx_lock(&nmp->nm_mtx); if ((nmp->nm_flag & NFSMNT_NFSV3) != 0 && (nmp->nm_state & NFSSTA_GOTFSINFO) == 0) { mtx_unlock(&nmp->nm_mtx); (void)nfs_fsinfo(nmp, vp, cred, td); } else mtx_unlock(&nmp->nm_mtx); end = uio->uio_offset + uio->uio_resid; if (vp->v_type != VDIR && (end > nmp->nm_maxfilesize || end < uio->uio_offset)) return (EFBIG); if (nfs_directio_enable && (ioflag & IO_DIRECT) && (vp->v_type == VREG)) /* No caching/ no readaheads. Just read data into the user buffer */ return nfs_readrpc(vp, uio, cred); biosize = vp->v_bufobj.bo_bsize; seqcount = (int)((off_t)(ioflag >> IO_SEQSHIFT) * biosize / BKVASIZE); error = nfs_bioread_check_cons(vp, td, cred); if (error) return error; do { u_quad_t nsize; mtx_lock(&np->n_mtx); nsize = np->n_size; mtx_unlock(&np->n_mtx); switch (vp->v_type) { case VREG: nfsstats.biocache_reads++; lbn = uio->uio_offset / biosize; on = uio->uio_offset - (lbn * biosize); /* * Start the read ahead(s), as required. */ if (nmp->nm_readahead > 0) { for (nra = 0; nra < nmp->nm_readahead && nra < seqcount && (off_t)(lbn + 1 + nra) * biosize < nsize; nra++) { rabn = lbn + 1 + nra; if (incore(&vp->v_bufobj, rabn) == NULL) { rabp = nfs_getcacheblk(vp, rabn, biosize, td); if (!rabp) { error = nfs_sigintr(nmp, td); return (error ? error : EINTR); } if ((rabp->b_flags & (B_CACHE|B_DELWRI)) == 0) { rabp->b_flags |= B_ASYNC; rabp->b_iocmd = BIO_READ; vfs_busy_pages(rabp, 0); if (nfs_asyncio(nmp, rabp, cred, td)) { rabp->b_flags |= B_INVAL; rabp->b_ioflags |= BIO_ERROR; vfs_unbusy_pages(rabp); brelse(rabp); break; } } else { brelse(rabp); } } } } /* Note that bcount is *not* DEV_BSIZE aligned. */ bcount = biosize; if ((off_t)lbn * biosize >= nsize) { bcount = 0; } else if ((off_t)(lbn + 1) * biosize > nsize) { bcount = nsize - (off_t)lbn * biosize; } bp = nfs_getcacheblk(vp, lbn, bcount, td); if (!bp) { error = nfs_sigintr(nmp, td); return (error ? error : 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_iocmd = BIO_READ; vfs_busy_pages(bp, 0); error = nfs_doio(vp, bp, cred, td); 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, td); if (!bp) { error = nfs_sigintr(nmp, td); return (error ? error : EINTR); } if ((bp->b_flags & B_CACHE) == 0) { bp->b_iocmd = BIO_READ; vfs_busy_pages(bp, 0); error = nfs_doio(vp, bp, cred, td); if (error) { bp->b_ioflags |= BIO_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, td); if (!bp) { error = nfs_sigintr(nmp, td); return (error ? error : EINTR); } if ((bp->b_flags & B_CACHE) == 0) { bp->b_iocmd = BIO_READ; vfs_busy_pages(bp, 0); error = nfs_doio(vp, bp, cred, td); if (error) { brelse(bp); } while (error == NFSERR_BAD_COOKIE) { (nmp->nm_rpcops->nr_invaldir)(vp); error = nfs_vinvalbuf(vp, 0, td, 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, td); if (!bp) { error = nfs_sigintr(nmp, td); return (error ? error : EINTR); } if ((bp->b_flags & B_CACHE) == 0) { bp->b_iocmd = BIO_READ; vfs_busy_pages(bp, 0); error = nfs_doio(vp, bp, cred, td); /* * 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 (nmp->nm_readahead > 0 && (bp->b_flags & B_INVAL) == 0 && (np->n_direofoffset == 0 || (lbn + 1) * NFS_DIRBLKSIZ < np->n_direofoffset) && incore(&vp->v_bufobj, lbn + 1) == NULL) { rabp = nfs_getcacheblk(vp, lbn + 1, NFS_DIRBLKSIZ, td); if (rabp) { if ((rabp->b_flags & (B_CACHE|B_DELWRI)) == 0) { rabp->b_flags |= B_ASYNC; rabp->b_iocmd = BIO_READ; vfs_busy_pages(rabp, 0); if (nfs_asyncio(nmp, rabp, cred, td)) { rabp->b_flags |= B_INVAL; rabp->b_ioflags |= BIO_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: nfs_printf(" nfs_bioread: type %x unexpected\n", vp->v_type); bp = NULL; break; }; if (n > 0) { error = uiomove(bp->b_data + on, (int)n, uio); } if (vp->v_type == VLNK) n = 0; if (bp != NULL) brelse(bp); } while (error == 0 && uio->uio_resid > 0 && n > 0); return (error); } /* * The NFS write path cannot handle iovecs with len > 1. So we need to * break up iovecs accordingly (restricting them to wsize). * For the SYNC case, we can do this with 1 copy (user buffer -> mbuf). * For the ASYNC case, 2 copies are needed. The first a copy from the * user buffer to a staging buffer and then a second copy from the staging * buffer to mbufs. This can be optimized by copying from the user buffer * directly into mbufs and passing the chain down, but that requires a * fair amount of re-working of the relevant codepaths (and can be done * later). */ static int nfs_directio_write(vp, uiop, cred, ioflag) struct vnode *vp; struct uio *uiop; struct ucred *cred; int ioflag; { int error; struct nfsmount *nmp = VFSTONFS(vp->v_mount); struct thread *td = uiop->uio_td; int size; int wsize; mtx_lock(&nmp->nm_mtx); wsize = nmp->nm_wsize; mtx_unlock(&nmp->nm_mtx); if (ioflag & IO_SYNC) { int iomode, must_commit; struct uio uio; struct iovec iov; do_sync: while (uiop->uio_resid > 0) { size = MIN(uiop->uio_resid, wsize); size = MIN(uiop->uio_iov->iov_len, size); iov.iov_base = uiop->uio_iov->iov_base; iov.iov_len = size; uio.uio_iov = &iov; uio.uio_iovcnt = 1; uio.uio_offset = uiop->uio_offset; uio.uio_resid = size; uio.uio_segflg = UIO_USERSPACE; uio.uio_rw = UIO_WRITE; uio.uio_td = td; iomode = NFSV3WRITE_FILESYNC; error = (nmp->nm_rpcops->nr_writerpc)(vp, &uio, cred, &iomode, &must_commit); KASSERT((must_commit == 0), ("nfs_directio_write: Did not commit write")); if (error) return (error); uiop->uio_offset += size; uiop->uio_resid -= size; if (uiop->uio_iov->iov_len <= size) { uiop->uio_iovcnt--; uiop->uio_iov++; } else { uiop->uio_iov->iov_base = (char *)uiop->uio_iov->iov_base + size; uiop->uio_iov->iov_len -= size; } } } else { struct uio *t_uio; struct iovec *t_iov; struct buf *bp; /* * Break up the write into blocksize chunks and hand these * over to nfsiod's for write back. * Unfortunately, this incurs a copy of the data. Since * the user could modify the buffer before the write is * initiated. * * The obvious optimization here is that one of the 2 copies * in the async write path can be eliminated by copying the * data here directly into mbufs and passing the mbuf chain * down. But that will require a fair amount of re-working * of the code and can be done if there's enough interest * in NFS directio access. */ while (uiop->uio_resid > 0) { size = MIN(uiop->uio_resid, wsize); size = MIN(uiop->uio_iov->iov_len, size); bp = getpbuf(&nfs_pbuf_freecnt); t_uio = malloc(sizeof(struct uio), M_NFSDIRECTIO, M_WAITOK); t_iov = malloc(sizeof(struct iovec), M_NFSDIRECTIO, M_WAITOK); t_iov->iov_base = malloc(size, M_NFSDIRECTIO, M_WAITOK); t_iov->iov_len = size; t_uio->uio_iov = t_iov; t_uio->uio_iovcnt = 1; t_uio->uio_offset = uiop->uio_offset; t_uio->uio_resid = size; t_uio->uio_segflg = UIO_SYSSPACE; t_uio->uio_rw = UIO_WRITE; t_uio->uio_td = td; KASSERT(uiop->uio_segflg == UIO_USERSPACE || uiop->uio_segflg == UIO_SYSSPACE, ("nfs_directio_write: Bad uio_segflg")); if (uiop->uio_segflg == UIO_USERSPACE) { error = copyin(uiop->uio_iov->iov_base, t_iov->iov_base, size); if (error != 0) goto err_free; } else /* * UIO_SYSSPACE may never happen, but handle * it just in case it does. */ bcopy(uiop->uio_iov->iov_base, t_iov->iov_base, size); bp->b_flags |= B_DIRECT; bp->b_iocmd = BIO_WRITE; if (cred != NOCRED) { crhold(cred); bp->b_wcred = cred; } else bp->b_wcred = NOCRED; bp->b_caller1 = (void *)t_uio; bp->b_vp = vp; error = nfs_asyncio(nmp, bp, NOCRED, td); err_free: if (error) { free(t_iov->iov_base, M_NFSDIRECTIO); free(t_iov, M_NFSDIRECTIO); free(t_uio, M_NFSDIRECTIO); bp->b_vp = NULL; relpbuf(bp, &nfs_pbuf_freecnt); if (error == EINTR) return (error); goto do_sync; } uiop->uio_offset += size; uiop->uio_resid -= size; if (uiop->uio_iov->iov_len <= size) { uiop->uio_iovcnt--; uiop->uio_iov++; } else { uiop->uio_iov->iov_base = (char *)uiop->uio_iov->iov_base + size; uiop->uio_iov->iov_len -= size; } } } return (0); } /* * Vnode op for write using bio */ int nfs_write(struct vop_write_args *ap) { int biosize; struct uio *uio = ap->a_uio; struct thread *td = uio->uio_td; 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; off_t end; int bcount; int n, on, error = 0; KASSERT(uio->uio_rw == UIO_WRITE, ("nfs_write mode")); KASSERT(uio->uio_segflg != UIO_USERSPACE || uio->uio_td == curthread, ("nfs_write proc")); if (vp->v_type != VREG) return (EIO); mtx_lock(&np->n_mtx); if (np->n_flag & NWRITEERR) { np->n_flag &= ~NWRITEERR; mtx_unlock(&np->n_mtx); return (np->n_error); } else mtx_unlock(&np->n_mtx); mtx_lock(&nmp->nm_mtx); if ((nmp->nm_flag & NFSMNT_NFSV3) != 0 && (nmp->nm_state & NFSSTA_GOTFSINFO) == 0) { mtx_unlock(&nmp->nm_mtx); (void)nfs_fsinfo(nmp, vp, cred, td); } else mtx_unlock(&nmp->nm_mtx); /* * Synchronously flush pending buffers if we are in synchronous * mode or if we are appending. */ if (ioflag & (IO_APPEND | IO_SYNC)) { mtx_lock(&np->n_mtx); if (np->n_flag & NMODIFIED) { mtx_unlock(&np->n_mtx); #ifdef notyet /* Needs matching nonblock semantics elsewhere, too. */ /* * Require non-blocking, synchronous writes to * dirty files to inform the program it needs * to fsync(2) explicitly. */ if (ioflag & IO_NDELAY) return (EAGAIN); #endif flush_and_restart: np->n_attrstamp = 0; KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(vp); error = nfs_vinvalbuf(vp, V_SAVE, td, 1); if (error) return (error); } else mtx_unlock(&np->n_mtx); } /* * If IO_APPEND then load uio_offset. We restart here if we cannot * get the append lock. */ if (ioflag & IO_APPEND) { np->n_attrstamp = 0; KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(vp); error = VOP_GETATTR(vp, &vattr, cred); if (error) return (error); mtx_lock(&np->n_mtx); uio->uio_offset = np->n_size; mtx_unlock(&np->n_mtx); } if (uio->uio_offset < 0) return (EINVAL); end = uio->uio_offset + uio->uio_resid; if (end > nmp->nm_maxfilesize || end < uio->uio_offset) return (EFBIG); if (uio->uio_resid == 0) return (0); if (nfs_directio_enable && (ioflag & IO_DIRECT) && vp->v_type == VREG) return nfs_directio_write(vp, uio, cred, ioflag); /* * 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 (vn_rlimit_fsize(vp, uio, td)) return (EFBIG); biosize = vp->v_bufobj.bo_bsize; /* * Find all of this file's B_NEEDCOMMIT buffers. If our writes * would exceed the local maximum per-file write commit size when * combined with those, we must decide whether to flush, * go synchronous, or return error. We don't bother checking * IO_UNIT -- we just make all writes atomic anyway, as there's * no point optimizing for something that really won't ever happen. */ if (!(ioflag & IO_SYNC)) { int nflag; mtx_lock(&np->n_mtx); nflag = np->n_flag; mtx_unlock(&np->n_mtx); int needrestart = 0; if (nmp->nm_wcommitsize < uio->uio_resid) { /* * If this request could not possibly be completed * without exceeding the maximum outstanding write * commit size, see if we can convert it into a * synchronous write operation. */ if (ioflag & IO_NDELAY) return (EAGAIN); ioflag |= IO_SYNC; if (nflag & NMODIFIED) needrestart = 1; } else if (nflag & NMODIFIED) { int wouldcommit = 0; BO_LOCK(&vp->v_bufobj); if (vp->v_bufobj.bo_dirty.bv_cnt != 0) { TAILQ_FOREACH(bp, &vp->v_bufobj.bo_dirty.bv_hd, b_bobufs) { if (bp->b_flags & B_NEEDCOMMIT) wouldcommit += bp->b_bcount; } } BO_UNLOCK(&vp->v_bufobj); /* * Since we're not operating synchronously and * bypassing the buffer cache, we are in a commit * and holding all of these buffers whether * transmitted or not. If not limited, this * will lead to the buffer cache deadlocking, * as no one else can flush our uncommitted buffers. */ wouldcommit += uio->uio_resid; /* * If we would initially exceed the maximum * outstanding write commit size, flush and restart. */ if (wouldcommit > nmp->nm_wcommitsize) needrestart = 1; } if (needrestart) goto flush_and_restart; } do { nfsstats.biocache_writes++; lbn = uio->uio_offset / biosize; on = uio->uio_offset - (lbn * biosize); n = MIN((unsigned)(biosize - on), uio->uio_resid); again: /* * Handle direct append and file extension cases, calculate * unaligned buffer size. */ mtx_lock(&np->n_mtx); if (uio->uio_offset == np->n_size && n) { mtx_unlock(&np->n_mtx); /* * 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, td); if (bp != NULL) { long save; mtx_lock(&np->n_mtx); np->n_size = uio->uio_offset + n; np->n_flag |= NMODIFIED; vnode_pager_setsize(vp, np->n_size); mtx_unlock(&np->n_mtx); 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; } mtx_unlock(&np->n_mtx); bp = nfs_getcacheblk(vp, lbn, bcount, td); mtx_lock(&np->n_mtx); 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); } mtx_unlock(&np->n_mtx); } if (!bp) { error = nfs_sigintr(nmp, td); if (!error) 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_INVAL; bp->b_ioflags &= ~BIO_ERROR; } if ((bp->b_flags & B_CACHE) == 0) { bp->b_iocmd = BIO_READ; vfs_busy_pages(bp, 0); error = nfs_doio(vp, bp, cred, td); if (error) { brelse(bp); break; } } if (bp->b_wcred == NOCRED) bp->b_wcred = crhold(cred); mtx_lock(&np->n_mtx); np->n_flag |= NMODIFIED; mtx_unlock(&np->n_mtx); /* * 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) { nfs_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 (bwrite(bp) == EINTR) { error = EINTR; break; } 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_ioflags |= BIO_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_valid(bp, on, n); } /* * If 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 ((ioflag & IO_SYNC)) { if (ioflag & IO_INVAL) bp->b_flags |= B_NOCACHE; error = bwrite(bp); if (error) break; } else if ((n + on) == biosize) { bp->b_flags |= B_ASYNC; (void) (nmp->nm_rpcops->nr_writebp)(bp, 0, NULL); } else { bdwrite(bp); } } while (uio->uio_resid > 0 && n > 0); 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(struct vnode *vp, daddr_t bn, int size, struct thread *td) { struct buf *bp; struct mount *mp; struct nfsmount *nmp; mp = vp->v_mount; nmp = VFSTONFS(mp); if (nmp->nm_flag & NFSMNT_INT) { sigset_t oldset; nfs_set_sigmask(td, &oldset); bp = getblk(vp, bn, size, PCATCH, 0, 0); nfs_restore_sigmask(td, &oldset); while (bp == NULL) { if (nfs_sigintr(nmp, td)) return (NULL); bp = getblk(vp, bn, size, 0, 2 * hz, 0); } } else { bp = getblk(vp, bn, size, 0, 0, 0); } if (vp->v_type == VREG) bp->b_blkno = bn * (vp->v_bufobj.bo_bsize / 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(struct vnode *vp, int flags, struct thread *td, int intrflg) { struct nfsnode *np = VTONFS(vp); struct nfsmount *nmp = VFSTONFS(vp->v_mount); int error = 0, slpflag, slptimeo; int old_lock = 0; ASSERT_VOP_LOCKED(vp, "nfs_vinvalbuf"); if ((nmp->nm_flag & NFSMNT_INT) == 0) intrflg = 0; if (intrflg) { slpflag = PCATCH; slptimeo = 2 * hz; } else { slpflag = 0; slptimeo = 0; } old_lock = nfs_upgrade_vnlock(vp); if (vp->v_iflag & VI_DOOMED) { /* * Since vgonel() uses the generic vinvalbuf() to flush * dirty buffers and it does not call this function, it * is safe to just return OK when VI_DOOMED is set. */ nfs_downgrade_vnlock(vp, old_lock); return (0); } /* * Now, flush as required. */ if ((flags & V_SAVE) && (vp->v_bufobj.bo_object != NULL)) { VM_OBJECT_WLOCK(vp->v_bufobj.bo_object); vm_object_page_clean(vp->v_bufobj.bo_object, 0, 0, OBJPC_SYNC); VM_OBJECT_WUNLOCK(vp->v_bufobj.bo_object); /* * If the page clean was interrupted, fail the invalidation. * Not doing so, we run the risk of losing dirty pages in the * vinvalbuf() call below. */ if (intrflg && (error = nfs_sigintr(nmp, td))) goto out; } error = vinvalbuf(vp, flags, slpflag, 0); while (error) { if (intrflg && (error = nfs_sigintr(nmp, td))) goto out; error = vinvalbuf(vp, flags, 0, slptimeo); } mtx_lock(&np->n_mtx); if (np->n_directio_asyncwr == 0) np->n_flag &= ~NMODIFIED; mtx_unlock(&np->n_mtx); out: nfs_downgrade_vnlock(vp, old_lock); return error; } /* * 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 (BIO_ERROR|B_INVAL) but when the bp * is eventually dequeued by the async daemon, nfs_doio() *will*. */ int nfs_asyncio(struct nfsmount *nmp, struct buf *bp, struct ucred *cred, struct thread *td) { int iod; int gotiod; int slpflag = 0; int slptimeo = 0; int error, error2; /* * Commits are usually short and sweet so lets save some cpu and * leave the async daemons for more important rpc's (such as reads * and writes). * * Readdirplus RPCs do vget()s to acquire the vnodes for entries * in the directory in order to update attributes. This can deadlock * with another thread that is waiting for async I/O to be done by * an nfsiod thread while holding a lock on one of these vnodes. * To avoid this deadlock, don't allow the async nfsiod threads to * perform Readdirplus RPCs. */ mtx_lock(&nfs_iod_mtx); if ((bp->b_iocmd == BIO_WRITE && (bp->b_flags & B_NEEDCOMMIT) && (nmp->nm_bufqiods > nfs_numasync / 2)) || (bp->b_vp->v_type == VDIR && (nmp->nm_flag & NFSMNT_RDIRPLUS))) { mtx_unlock(&nfs_iod_mtx); return(EIO); } again: if (nmp->nm_flag & NFSMNT_INT) slpflag = PCATCH; gotiod = FALSE; /* * Find a free iod to process this request. */ for (iod = 0; iod < nfs_numasync; iod++) if (nfs_iodwant[iod] == NFSIOD_AVAILABLE) { gotiod = TRUE; break; } /* * Try to create one if none are free. */ if (!gotiod) nfs_nfsiodnew(); else { /* * 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", iod, nmp)); nfs_iodwant[iod] = NFSIOD_NOT_AVAILABLE; nfs_iodmount[iod] = nmp; nmp->nm_bufqiods++; wakeup(&nfs_iodwant[iod]); } /* * 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. We still want * to asynchronize so we block rather then return EIO. */ 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 = nfs_msleep(td, &nmp->nm_bufq, &nfs_iod_mtx, slpflag | PRIBIO, "nfsaio", slptimeo); if (error) { error2 = nfs_sigintr(nmp, td); if (error2) { mtx_unlock(&nfs_iod_mtx); return (error2); } if (slpflag == PCATCH) { slpflag = 0; slptimeo = 2 * hz; } } /* * We might have lost our iod while sleeping, * so check and loop if nescessary. */ goto again; } /* We might have lost our nfsiod */ 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_iocmd == BIO_READ) { if (bp->b_rcred == NOCRED && cred != NOCRED) bp->b_rcred = crhold(cred); } else { if (bp->b_wcred == NOCRED && cred != NOCRED) bp->b_wcred = crhold(cred); } if (bp->b_flags & B_REMFREE) bremfreef(bp); BUF_KERNPROC(bp); TAILQ_INSERT_TAIL(&nmp->nm_bufq, bp, b_freelist); nmp->nm_bufqlen++; if ((bp->b_flags & B_DIRECT) && bp->b_iocmd == BIO_WRITE) { mtx_lock(&(VTONFS(bp->b_vp))->n_mtx); VTONFS(bp->b_vp)->n_flag |= NMODIFIED; VTONFS(bp->b_vp)->n_directio_asyncwr++; mtx_unlock(&(VTONFS(bp->b_vp))->n_mtx); } mtx_unlock(&nfs_iod_mtx); return (0); } mtx_unlock(&nfs_iod_mtx); /* * 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); } void nfs_doio_directwrite(struct buf *bp) { int iomode, must_commit; struct uio *uiop = (struct uio *)bp->b_caller1; char *iov_base = uiop->uio_iov->iov_base; struct nfsmount *nmp = VFSTONFS(bp->b_vp->v_mount); iomode = NFSV3WRITE_FILESYNC; uiop->uio_td = NULL; /* NULL since we're in nfsiod */ (nmp->nm_rpcops->nr_writerpc)(bp->b_vp, uiop, bp->b_wcred, &iomode, &must_commit); KASSERT((must_commit == 0), ("nfs_doio_directwrite: Did not commit write")); free(iov_base, M_NFSDIRECTIO); free(uiop->uio_iov, M_NFSDIRECTIO); free(uiop, M_NFSDIRECTIO); if ((bp->b_flags & B_DIRECT) && bp->b_iocmd == BIO_WRITE) { struct nfsnode *np = VTONFS(bp->b_vp); mtx_lock(&np->n_mtx); np->n_directio_asyncwr--; if (np->n_directio_asyncwr == 0) { VTONFS(bp->b_vp)->n_flag &= ~NMODIFIED; if ((np->n_flag & NFSYNCWAIT)) { np->n_flag &= ~NFSYNCWAIT; wakeup((caddr_t)&np->n_directio_asyncwr); } } mtx_unlock(&np->n_mtx); } bp->b_vp = NULL; relpbuf(bp, &nfs_pbuf_freecnt); } /* * Do an I/O operation to/from a cache block. This may be called * synchronously or from an nfsiod. */ int nfs_doio(struct vnode *vp, struct buf *bp, struct ucred *cr, struct thread *td) { struct uio *uiop; struct nfsnode *np; struct nfsmount *nmp; int error = 0, iomode, must_commit = 0; struct uio uio; struct iovec io; struct proc *p = td ? td->td_proc : NULL; uint8_t iocmd; 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_td = td; /* * clear BIO_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_INVAL; bp->b_ioflags &= ~BIO_ERROR; KASSERT(!(bp->b_flags & B_DONE), ("nfs_doio: bp %p already marked done", bp)); iocmd = bp->b_iocmd; if (iocmd == BIO_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 = (nmp->nm_rpcops->nr_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 = uiop->uio_resid; if (left > 0) bzero((char *)bp->b_data + nread, left); uiop->uio_resid = 0; } } /* ASSERT_VOP_LOCKED(vp, "nfs_doio"); */ if (p && (vp->v_vflag & VV_TEXT)) { mtx_lock(&np->n_mtx); if (NFS_TIMESPEC_COMPARE(&np->n_mtime, &np->n_vattr.va_mtime)) { mtx_unlock(&np->n_mtx); PROC_LOCK(p); killproc(p, "text file modification"); PROC_UNLOCK(p); } else mtx_unlock(&np->n_mtx); } break; case VLNK: uiop->uio_offset = (off_t)0; nfsstats.readlink_bios++; error = (nmp->nm_rpcops->nr_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) != 0) { 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: nfs_printf("nfs_doio: type %x unexpected\n", vp->v_type); break; }; if (error) { bp->b_ioflags |= BIO_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; retv = (nmp->nm_rpcops->nr_commit)( vp, off, bp->b_dirtyend-bp->b_dirtyoff, bp->b_wcred, td); if (retv == 0) { bp->b_dirtyoff = bp->b_dirtyend = 0; bp->b_flags &= ~(B_NEEDCOMMIT | B_CLUSTEROK); bp->b_resid = 0; bufdone(bp); return (0); } if (retv == NFSERR_STALEWRITEVERF) { nfs_clearcommit(vp->v_mount); } } /* * Setup for actual write */ mtx_lock(&np->n_mtx); 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; mtx_unlock(&np->n_mtx); 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; error = (nmp->nm_rpcops->nr_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); } /* * 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 BIO_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 * * The logic below breaks up errors into recoverable and * unrecoverable. For the former, we clear B_INVAL|B_NOCACHE * and keep the buffer around for potential write retries. * For the latter (eg ESTALE), we toss the buffer away (B_INVAL) * and save the error in the nfsnode. This is less than ideal * but necessary. Keeping such buffers around could potentially * cause buffer exhaustion eventually (they can never be written * out, so will get constantly be re-dirtied). It also causes * all sorts of vfs panics. For non-recoverable write errors, * also invalidate the attrcache, so we'll be forced to go over * the wire for this object, returning an error to user on next * call (most of the time). */ if (error == EINTR || error == EIO || error == ETIMEDOUT || (!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_ioflags |= BIO_ERROR; bp->b_flags |= B_INVAL; bp->b_error = np->n_error = error; mtx_lock(&np->n_mtx); np->n_flag |= NWRITEERR; np->n_attrstamp = 0; KDTRACE_NFS_ATTRCACHE_FLUSH_DONE(vp); mtx_unlock(&np->n_mtx); } bp->b_dirtyoff = bp->b_dirtyend = 0; } } else { bp->b_resid = 0; bufdone(bp); return (0); } } bp->b_resid = uiop->uio_resid; if (must_commit) nfs_clearcommit(vp->v_mount); bufdone(bp); return (error); } /* * Used to aid in handling ftruncate() operations on the NFS client side. * Truncation creates a number of special problems for NFS. We have to * throw away VM pages and buffer cache buffers that are beyond EOF, and * we have to properly handle VM pages or (potentially dirty) buffers * that straddle the truncation point. */ int nfs_meta_setsize(struct vnode *vp, struct ucred *cred, struct thread *td, u_quad_t nsize) { struct nfsnode *np = VTONFS(vp); u_quad_t tsize; int biosize = vp->v_bufobj.bo_bsize; int error = 0; mtx_lock(&np->n_mtx); tsize = np->n_size; np->n_size = nsize; mtx_unlock(&np->n_mtx); if (nsize < tsize) { struct buf *bp; daddr_t lbn; int bufsize; /* * vtruncbuf() doesn't get the buffer overlapping the * truncation point. We may have a B_DELWRI and/or B_CACHE * buffer that now needs to be truncated. */ error = vtruncbuf(vp, cred, nsize, biosize); lbn = nsize / biosize; bufsize = nsize - (lbn * biosize); bp = nfs_getcacheblk(vp, lbn, bufsize, td); if (!bp) return EINTR; if (bp->b_dirtyoff > bp->b_bcount) bp->b_dirtyoff = bp->b_bcount; if (bp->b_dirtyend > bp->b_bcount) bp->b_dirtyend = bp->b_bcount; bp->b_flags |= B_RELBUF; /* don't leave garbage around */ brelse(bp); } else { vnode_pager_setsize(vp, nsize); } return(error); }