/* * Copyright (c) 2000 Apple Computer, Inc. All rights reserved. * * @APPLE_LICENSE_HEADER_START@ * * The contents of this file constitute Original Code as defined in and * are subject to the Apple Public Source License Version 1.1 (the * "License"). You may not use this file except in compliance with the * License. Please obtain a copy of the License at * http://www.apple.com/publicsource and read it before using this file. * * This Original Code and all software distributed under the License are * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT. Please see the * License for the specific language governing rights and limitations * under the License. * * @APPLE_LICENSE_HEADER_END@ */ /* Copyright (c) 1995 NeXT Computer, Inc. All Rights Reserved */ /* * 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-Id: nfs_bio.c,v 1.44 1997/09/10 19:52:25 phk Exp $ */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #define FSDBG(A, B, C, D, E) \ KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, (A))) | DBG_FUNC_NONE, \ (int)(B), (int)(C), (int)(D), (int)(E), 0) #define FSDBG_TOP(A, B, C, D, E) \ KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, (A))) | DBG_FUNC_START, \ (int)(B), (int)(C), (int)(D), (int)(E), 0) #define FSDBG_BOT(A, B, C, D, E) \ KERNEL_DEBUG((FSDBG_CODE(DBG_FSRW, (A))) | DBG_FUNC_END, \ (int)(B), (int)(C), (int)(D), (int)(E), 0) static struct buf *nfs_getcacheblk __P((struct vnode *vp, daddr_t bn, int size, struct proc *p, int operation)); extern int nfs_numasync; extern struct nfsstats nfsstats; extern int nbdwrite; /* * Vnode op for read using bio * Any similarity to readip() is purely coincidental */ int nfs_bioread(vp, uio, ioflag, cred, getpages) register struct vnode *vp; register struct uio *uio; int ioflag; struct ucred *cred; int getpages; { register struct nfsnode *np = VTONFS(vp); register int biosize, diff, i; struct buf *bp = 0, *rabp; struct vattr vattr; struct proc *p; struct nfsmount *nmp = VFSTONFS(vp->v_mount); daddr_t lbn, rabn; int bufsize; int nra, error = 0, n = 0, on = 0, not_readin; int operation = (getpages? BLK_PAGEIN : BLK_READ); #if DIAGNOSTIC if (uio->uio_rw != UIO_READ) panic("nfs_read mode"); #endif if (uio->uio_resid == 0) return (0); if (uio->uio_offset < 0) return (EINVAL); p = uio->uio_procp; if ((nmp->nm_flag & (NFSMNT_NFSV3 | NFSMNT_GOTFSINFO)) == NFSMNT_NFSV3) (void)nfs_fsinfo(nmp, vp, cred, p); /*due to getblk/vm interractions, use vm page size or less values */ biosize = min(vp->v_mount->mnt_stat.f_iosize, PAGE_SIZE); /* * 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); not_readin = 1; /* * Start the read ahead(s), as required. */ if (nfs_numasync > 0 && nmp->nm_readahead > 0) { for (nra = 0; nra < nmp->nm_readahead && (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, operation); if (!rabp) return (EINTR); if (!ISSET(rabp->b_flags, (B_CACHE|B_DELWRI))) { SET(rabp->b_flags, (B_READ | B_ASYNC)); if (nfs_asyncio(rabp, cred)) { SET(rabp->b_flags, (B_INVAL|B_ERROR)); rabp->b_error = EIO; brelse(rabp); } } else brelse(rabp); } } } /* * If the block is in the cache and has the required data * in a valid region, just copy it out. * Otherwise, get the block and write back/read in, * as required. */ again: bufsize = biosize; if ((off_t)(lbn + 1) * biosize > np->n_size && (off_t)(lbn + 1) * biosize - np->n_size < biosize) { bufsize = np->n_size - lbn * biosize; bufsize = (bufsize + DEV_BSIZE - 1) & ~(DEV_BSIZE - 1); } bp = nfs_getcacheblk(vp, lbn, bufsize, p, operation); if (!bp) return (EINTR); if (!ISSET(bp->b_flags, B_CACHE)) { SET(bp->b_flags, B_READ); CLR(bp->b_flags, (B_DONE | B_ERROR | B_INVAL)); not_readin = 0; error = nfs_doio(bp, cred, p); if (error) { brelse(bp); return (error); } } if (bufsize > on) { n = min((unsigned)(bufsize - on), uio->uio_resid); } else { n = 0; } diff = np->n_size - uio->uio_offset; if (diff < n) n = diff; if (not_readin && n > 0) { if (on < bp->b_validoff || (on + n) > bp->b_validend) { SET(bp->b_flags, (B_NOCACHE|B_INVAFTERWRITE)); if (bp->b_dirtyend > 0) { if (!ISSET(bp->b_flags, B_DELWRI)) panic("nfsbioread"); if (VOP_BWRITE(bp) == EINTR) return (EINTR); } else brelse(bp); goto again; } } vp->v_lastr = lbn; diff = (on >= bp->b_validend) ? 0 : (bp->b_validend - on); if (diff < n) n = diff; break; case VLNK: nfsstats.biocache_readlinks++; bp = nfs_getcacheblk(vp, (daddr_t)0, NFS_MAXPATHLEN, p, operation); if (!bp) return (EINTR); if (!ISSET(bp->b_flags, B_CACHE)) { SET(bp->b_flags, B_READ); error = nfs_doio(bp, cred, p); if (error) { SET(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 = uio->uio_offset / NFS_DIRBLKSIZ; on = uio->uio_offset & (NFS_DIRBLKSIZ - 1); bp = nfs_getcacheblk(vp, lbn, NFS_DIRBLKSIZ, p, operation); if (!bp) return (EINTR); if (!ISSET(bp->b_flags, B_CACHE)) { SET(bp->b_flags, B_READ); error = nfs_doio(bp, cred, p); if (error) { brelse(bp); } while (error == NFSERR_BAD_COOKIE) { 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. */ 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, operation); if (!bp) return (EINTR); if (!ISSET(bp->b_flags, B_CACHE)) { SET(bp->b_flags, B_READ); 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 && (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, operation); if (rabp) { if (!ISSET(rabp->b_flags, (B_CACHE|B_DELWRI))) { SET(rabp->b_flags, (B_READ | B_ASYNC)); if (nfs_asyncio(rabp, cred)) { SET(rabp->b_flags, (B_INVAL|B_ERROR)); rabp->b_error = EIO; brelse(rabp); } } else { brelse(rabp); } } } /* * Make sure we use a signed variant of min() since * the second term may be negative. */ n = lmin(uio->uio_resid, NFS_DIRBLKSIZ - bp->b_resid - on); /* * 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 (recovered * from VM) later. So we keep track of the directory eof * in np->n_direofoffset and chop it off as an extra step * right here. */ 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: if (np->n_flag & NQNFSNONCACHE) SET(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; { register int biosize; register struct uio *uio = ap->a_uio; struct proc *p = uio->uio_procp; register struct vnode *vp = ap->a_vp; struct nfsnode *np = VTONFS(vp); register 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 bufsize; int n, on, error = 0, iomode, must_commit; off_t boff; struct iovec iov; struct uio auio; #if DIAGNOSTIC if (uio->uio_rw != UIO_WRITE) panic("nfs_write mode"); if (uio->uio_segflg == UIO_USERSPACE && uio->uio_procp != current_proc()) 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 | NFSMNT_GOTFSINFO)) == NFSMNT_NFSV3) (void)nfs_fsinfo(nmp, vp, cred, p); 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 (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_resid == 0) return (0); /* * 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); return (EFBIG); } /* * I use nm_rsize, not nm_wsize so that all buffer cache blocks * will be the same size within a filesystem. nfs_writerpc will * still use nm_wsize when sizing the rpc's. */ /*due to getblk/vm interractions, use vm page size or less values */ biosize = min(vp->v_mount->mnt_stat.f_iosize, PAGE_SIZE); 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) return (error); if (np->n_lrev != np->n_brev || (np->n_flag & NQNFSNONCACHE)) { error = nfs_vinvalbuf(vp, V_SAVE, cred, p, 1); if (error) return (error); 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); return (error); } nfsstats.biocache_writes++; lbn = uio->uio_offset / biosize; on = uio->uio_offset & (biosize-1); n = min((unsigned)(biosize - on), uio->uio_resid); again: bufsize = biosize; #if 0 /* (removed for UBC) */ if ((lbn + 1) * biosize > np->n_size) { bufsize = np->n_size - lbn * biosize; bufsize = (bufsize + DEV_BSIZE - 1) & ~(DEV_BSIZE - 1); } #endif /* * Get a cache block for writing. The range to be written is * (off..off+len) within the block. We ensure that the block * either has no dirty region or that the given range is * contiguous with the existing dirty region. */ bp = nfs_getcacheblk(vp, lbn, bufsize, p, BLK_WRITE); if (!bp) return (EINTR); /* * Resize nfsnode *after* we busy the buffer to prevent * readers from reading garbage. * If there was a partial buf at the old eof, validate * and zero the new bytes. */ if (uio->uio_offset + n > np->n_size) { struct buf *bp0 = NULL; daddr_t bn = np->n_size / biosize; int off = np->n_size & (biosize - 1); if (off && bn < lbn && incore(vp, bn)) bp0 = nfs_getcacheblk(vp, bn, biosize, p, BLK_WRITE); np->n_flag |= NMODIFIED; np->n_size = uio->uio_offset + n; ubc_setsize(vp, (off_t)np->n_size); /* XXX errors */ if (bp0) { bzero((char *)bp0->b_data + off, biosize - off); bp0->b_validend = biosize; brelse(bp0); } } /* * NFS has embedded ucred so crhold() risks zone corruption */ if (bp->b_wcred == NOCRED) bp->b_wcred = crdup(cred); /* * If dirtyend exceeds file size, chop it down. This should * not occur unless there is a race. */ 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; /* * UBC doesn't (yet) handle partial pages so nfs_biowrite was * hacked to never bdwrite, to start every little write right * away. Running IE Avie noticed the performance problem, thus * this code, which permits those delayed writes by ensuring an * initial read of the entire page. The read may hit eof * ("short read") but that we will handle. * * We are quite dependant on the correctness of B_CACHE so check * that first in case of problems. */ if (!ISSET(bp->b_flags, B_CACHE) && n < PAGE_SIZE) { boff = (off_t)bp->b_blkno * DEV_BSIZE; auio.uio_iov = &iov; auio.uio_iovcnt = 1; auio.uio_offset = boff; auio.uio_resid = PAGE_SIZE; auio.uio_segflg = UIO_SYSSPACE; auio.uio_rw = UIO_READ; auio.uio_procp = p; iov.iov_base = bp->b_data; iov.iov_len = PAGE_SIZE; error = nfs_readrpc(vp, &auio, cred); if (error) { bp->b_error = error; SET(bp->b_flags, B_ERROR); printf("nfs_write: readrpc %d", error); } if (auio.uio_resid > 0) bzero(iov.iov_base, auio.uio_resid); bp->b_validoff = 0; bp->b_validend = PAGE_SIZE - auio.uio_resid; if (np->n_size > boff + bp->b_validend) bp->b_validend = min(np->n_size - boff, PAGE_SIZE); bp->b_dirtyoff = 0; bp->b_dirtyend = 0; } /* * If the new write will leave a contiguous dirty * area, just update the b_dirtyoff and b_dirtyend, * otherwise try to extend the dirty region. */ if (bp->b_dirtyend > 0 && (on > bp->b_dirtyend || (on + n) < bp->b_dirtyoff)) { off_t start, end; boff = (off_t)bp->b_blkno * DEV_BSIZE; if (on > bp->b_dirtyend) { start = boff + bp->b_validend; end = boff + on; } else { start = boff + on + n; end = boff + bp->b_validoff; } /* * It may be that the valid region in the buffer * covers the region we want, in which case just * extend the dirty region. Otherwise we try to * extend the valid region. */ if (end > start) { auio.uio_iov = &iov; auio.uio_iovcnt = 1; auio.uio_offset = start; auio.uio_resid = end - start; auio.uio_segflg = UIO_SYSSPACE; auio.uio_rw = UIO_READ; auio.uio_procp = p; iov.iov_base = bp->b_data + (start - boff); iov.iov_len = end - start; error = nfs_readrpc(vp, &auio, cred); /* * If we couldn't read, do not do a VOP_BWRITE * as originally coded. That could also error * and looping back to "again" as it was doing * could have us stuck trying to write same buf * again. nfs_write, will get the entire region * if nfs_readrpc succeeded. If unsuccessful * we should just error out. Errors like ESTALE * would keep us looping rather than transient * errors justifying a retry. We can return here * instead of altering dirty region later. We * did not write old dirty region at this point. */ if (error) { bp->b_error = error; SET(bp->b_flags, B_ERROR); printf("nfs_write: readrpc2 %d", error); brelse(bp); return (error); } /* * The read worked. * If there was a short read, just zero fill. */ if (auio.uio_resid > 0) bzero(iov.iov_base, auio.uio_resid); if (on > bp->b_dirtyend) bp->b_validend = on; else bp->b_validoff = on + n; } /* * We now have a valid region which extends up to the * dirty region which we want. */ if (on > bp->b_dirtyend) bp->b_dirtyend = on; else bp->b_dirtyoff = on + n; } if (ISSET(bp->b_flags, B_ERROR)) { error = bp->b_error; brelse(bp); return (error); } /* * NFS has embedded ucred so crhold() risks zone corruption */ if (bp->b_wcred == NOCRED) bp->b_wcred = crdup(cred); np->n_flag |= NMODIFIED; /* * 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); return (error); } if (np->n_lrev != np->n_brev || (np->n_flag & NQNFSNONCACHE)) { brelse(bp); error = nfs_vinvalbuf(vp, V_SAVE, cred, p, 1); if (error) return (error); np->n_brev = np->n_lrev; goto again; } } error = uiomove((char *)bp->b_data + on, n, uio); if (error) { SET(bp->b_flags, B_ERROR); brelse(bp); return (error); } 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; } if (bp->b_validend == 0 || bp->b_validend < bp->b_dirtyoff || bp->b_validoff > bp->b_dirtyend) { bp->b_validoff = bp->b_dirtyoff; bp->b_validend = bp->b_dirtyend; } else { bp->b_validoff = min(bp->b_validoff, bp->b_dirtyoff); bp->b_validend = max(bp->b_validend, bp->b_dirtyend); } /* * Since this block is being modified, it must be written * again and not just committed. */ CLR(bp->b_flags, B_NEEDCOMMIT); /* * If the lease is non-cachable or IO_SYNC do bwrite(). */ if ((np->n_flag & NQNFSNONCACHE) || (ioflag & IO_SYNC)) { bp->b_proc = p; error = VOP_BWRITE(bp); if (error) return (error); if (np->n_flag & NQNFSNONCACHE) { error = nfs_vinvalbuf(vp, V_SAVE, cred, p, 1); if (error) return (error); } } else if ((n + on) == biosize && (nmp->nm_flag & NFSMNT_NQNFS) == 0) { bp->b_proc = (struct proc *)0; SET(bp->b_flags, B_ASYNC); (void)nfs_writebp(bp, 0); } else bdwrite(bp); } while (uio->uio_resid > 0 && n > 0); return (0); } /* * 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. */ static struct buf * nfs_getcacheblk(vp, bn, size, p, operation) struct vnode *vp; daddr_t bn; int size; struct proc *p; int operation; /* defined in sys/buf.h */ { register struct buf *bp; struct nfsmount *nmp = VFSTONFS(vp->v_mount); /*due to getblk/vm interractions, use vm page size or less values */ int biosize = min(vp->v_mount->mnt_stat.f_iosize, PAGE_SIZE); if (nbdwrite > ((nbuf/4)*3) && operation == BLK_WRITE) { #define __BUFFERS_RECLAIMED 2 struct buf *tbp[__BUFFERS_RECLAIMED]; int i; /* too many delayed writes, try to free up some buffers */ for (i = 0; i < __BUFFERS_RECLAIMED; i++) tbp[i] = geteblk(512); /* Yield to IO thread */ (void)tsleep((caddr_t)&nbdwrite, PCATCH, "nbdwrite", 1); for (i = (__BUFFERS_RECLAIMED - 1); i >= 0; i--) brelse(tbp[i]); } if (nmp->nm_flag & NFSMNT_INT) { bp = getblk(vp, bn, size, PCATCH, 0, operation); 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, operation); } } else bp = getblk(vp, bn, size, 0, 0, operation); if( vp->v_type == VREG) 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; int didhold = 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) { /* we seem to be stuck in a loop here if the thread got aborted. * nfs_flush will return EINTR. Not sure if that will cause * other consequences due to EINTR having other meanings in NFS * To handle, no dirty pages, it seems safe to just return from * here. But if we did have dirty pages, how would we get them * written out if thread was aborted? Some other strategy is * necessary. -- EKN */ if ((intrflg && nfs_sigintr(nmp, (struct nfsreq *)0, p)) || (error == EINTR && current_thread_aborted())) { 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); } didhold = ubc_hold(vp); if (didhold) { (void) ubc_clean(vp, 1); /* get the pages out of vm also */ ubc_rele(vp); } 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. */ int nfs_asyncio(bp, cred) register struct buf *bp; struct ucred *cred; { 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, bp->b_proc)) 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 (ISSET(bp->b_flags, B_READ)) { if (bp->b_rcred == NOCRED && cred != NOCRED) { /* * NFS has embedded ucred. * Can not crhold() here as that causes zone corruption */ bp->b_rcred = crdup(cred); } } else { SET(bp->b_flags, B_WRITEINPROG); if (bp->b_wcred == NOCRED && cred != NOCRED) { /* * NFS has embedded ucred. * Can not crhold() here as that causes zone corruption */ bp->b_wcred = crdup(cred); } } 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) register struct buf *bp; struct ucred *cr; struct proc *p; { register struct uio *uiop; register struct vnode *vp; struct nfsnode *np; struct nfsmount *nmp; int error = 0, diff, len, 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; /* * With UBC, getblk() can return a buf with B_DONE set. * This indicates that the VM has valid data for that page. * NFS being stateless, this case poses a problem. * By definition, the NFS server should always be consulted * for the data in that page. * So we choose to clear the B_DONE and to do the IO. * * XXX revisit this if there is a performance issue. * XXX In that case, we could play the attribute cache games ... */ if (ISSET(bp->b_flags, B_DONE)) { if (!ISSET(bp->b_flags, B_ASYNC)) panic("nfs_doio: done and not async"); CLR(bp->b_flags, B_DONE); } FSDBG_TOP(256, np->n_size, bp->b_blkno * DEV_BSIZE, bp->b_bcount, bp->b_flags); FSDBG(257, bp->b_validoff, bp->b_validend, bp->b_dirtyoff, bp->b_dirtyend); /* * Historically, paging was done with physio, but no more. */ if (ISSET(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 (ISSET(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) { SET(bp->b_flags, B_ERROR); bp->b_error = error; } } else if (ISSET(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); FSDBG(262, np->n_size, bp->b_blkno * DEV_BSIZE, uiop->uio_resid, error); if (!error) { bp->b_validoff = 0; if (uiop->uio_resid) { /* * If len > 0, there is a hole in the file and * no writes after the hole have been pushed to * the server yet. * Just zero fill the rest of the valid area. */ diff = bp->b_bcount - uiop->uio_resid; len = np->n_size - ((u_quad_t)bp->b_blkno * DEV_BSIZE + diff); if (len > 0) { len = min(len, uiop->uio_resid); bzero((char *)bp->b_data + diff, len); bp->b_validend = diff + len; FSDBG(258, diff, len, 0, 1); } else bp->b_validend = diff; } else bp->b_validend = bp->b_bcount; if (bp->b_validend < bp->b_bufsize) { /* * we're about to release a partial buffer after a * read... the only way we should get here is if * this buffer contains the EOF before releasing it, * we'll zero out to the end of the buffer so that * if a mmap of this page occurs, we'll see zero's * even if a ftruncate extends the file in the * meantime */ bzero((caddr_t)(bp->b_data + bp->b_validend), bp->b_bufsize - bp->b_validend); FSDBG(258, bp->b_validend, bp->b_bufsize - bp->b_validend, 0, 2); } } 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); p->p_flag |= P_NOSWAP; } 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_NFSV3)) nmp->nm_flag &= ~NFSMNT_RDIRPLUS; /* dk@farm.org */ 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); break; default: printf("nfs_doio: type %x unexpected\n", vp->v_type); break; }; if (error) { SET(bp->b_flags, B_ERROR); bp->b_error = error; } } else { /* * mapped I/O may have altered any bytes, so we extend * the dirty zone to the valid zone. For best performance * a better solution would be to save & restore page dirty bits * around the uiomove which brings write-data into the buffer. * Then here we'd check if the page is dirty rather than WASMAPPED * Also vnode_pager would change - if a page is clean it might * still need to be written due to DELWRI. */ if (UBCINFOEXISTS(vp) && ubc_issetflags(vp, UI_WASMAPPED)) { bp->b_dirtyoff = min(bp->b_dirtyoff, bp->b_validoff); bp->b_dirtyend = max(bp->b_dirtyend, bp->b_validend); } 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_ASYNC) iomode = NFSV3WRITE_UNSTABLE; else iomode = NFSV3WRITE_FILESYNC; SET(bp->b_flags, B_WRITEINPROG); error = nfs_writerpc(vp, uiop, cr, &iomode, &must_commit); if (!error && iomode == NFSV3WRITE_UNSTABLE) SET(bp->b_flags, B_NEEDCOMMIT); else CLR(bp->b_flags, B_NEEDCOMMIT); CLR(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 (error == EINTR || (!error && bp->b_flags & B_NEEDCOMMIT)) { int s; CLR(bp->b_flags, B_INVAL | B_NOCACHE); if (!ISSET(bp->b_flags, B_DELWRI)) { SET(bp->b_flags, B_DELWRI); nbdwrite++; } FSDBG(261, bp->b_validoff, bp->b_validend, bp->b_bufsize, bp->b_bcount); /* * Since for the B_ASYNC case, nfs_bwrite() has * reassigned the buffer to the clean list, we have to * reassign it back to the dirty one. Ugh. */ if (ISSET(bp->b_flags, B_ASYNC)) { s = splbio(); reassignbuf(bp, vp); splx(s); } else { SET(bp->b_flags, B_EINTR); } } else { if (error) { SET(bp->b_flags, B_ERROR); bp->b_error = np->n_error = error; np->n_flag |= NWRITEERR; } bp->b_dirtyoff = bp->b_dirtyend = 0; /* * validoff and validend represent the real data present * in this buffer if validoff is non-zero, than we have * to invalidate the buffer and kill the page when * biodone is called... the same is also true when * validend doesn't extend all the way to the end of the * buffer and validend doesn't equate to the current * EOF... eventually we need to deal with this in a more * humane way (like keeping the partial buffer without * making it immediately available to the VM page cache) */ if (bp->b_validoff) SET(bp->b_flags, B_INVAL); else if (bp->b_validend < bp->b_bufsize) { if ((off_t)bp->b_blkno * DEV_BSIZE + bp->b_validend == np->n_size) { bzero((caddr_t)(bp->b_data + bp->b_validend), bp->b_bufsize - bp->b_validend); FSDBG(259, bp->b_validend, bp->b_bufsize - bp->b_validend, 0, 0); } else SET(bp->b_flags, B_INVAL); } } } else { if (bp->b_validoff || (bp->b_validend < bp->b_bufsize && (off_t)bp->b_blkno * DEV_BSIZE + bp->b_validend != np->n_size)) { SET(bp->b_flags, B_INVAL); } if (bp->b_flags & B_INVAL) { FSDBG(260, bp->b_validoff, bp->b_validend, bp->b_bufsize, bp->b_bcount); } bp->b_resid = 0; biodone(bp); FSDBG_BOT(256, bp->b_validoff, bp->b_validend, bp->b_bufsize, np->n_size); return (0); } } bp->b_resid = uiop->uio_resid; if (must_commit) nfs_clearcommit(vp->v_mount); if (bp->b_flags & B_INVAL) { FSDBG(260, bp->b_validoff, bp->b_validend, bp->b_bufsize, bp->b_bcount); } FSDBG_BOT(256, bp->b_validoff, bp->b_validend, bp->b_bcount, error); biodone(bp); return (error); }