1 /* 2 * Copyright (c) 1989 The Regents of the University of California. 3 * All rights reserved. 4 * 5 * This code is derived from software contributed to Berkeley by 6 * Rick Macklem at The University of Guelph. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. All advertising materials mentioning features or use of this software 17 * must display the following acknowledgement: 18 * This product includes software developed by the University of 19 * California, Berkeley and its contributors. 20 * 4. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 * 36 * from: @(#)nfs_bio.c 7.19 (Berkeley) 4/16/91 37 * $Id: nfs_bio.c,v 1.6 1993/07/13 10:50:04 cgd Exp $ 38 */ 39 40 #include "param.h" 41 #include "proc.h" 42 #include "buf.h" 43 #include "uio.h" 44 #include "namei.h" 45 #include "vnode.h" 46 #include "trace.h" 47 #include "mount.h" 48 #include "resourcevar.h" 49 50 #include "nfsnode.h" 51 #include "nfsv2.h" 52 #include "nfs.h" 53 #include "nfsiom.h" 54 #include "nfsmount.h" 55 56 /* True and false, how exciting */ 57 #define TRUE 1 58 #define FALSE 0 59 60 /* 61 * Vnode op for read using bio 62 * Any similarity to readip() is purely coincidental 63 */ 64 nfs_bioread(vp, uio, ioflag, cred) 65 register struct vnode *vp; 66 register struct uio *uio; 67 int ioflag; 68 struct ucred *cred; 69 { 70 register struct nfsnode *np = VTONFS(vp); 71 register int biosize; 72 struct buf *bp; 73 struct vattr vattr; 74 daddr_t lbn, bn, rablock; 75 int diff, error = 0; 76 long n, on; 77 78 #ifdef lint 79 ioflag = ioflag; 80 #endif /* lint */ 81 #ifdef DIAGNOSTIC 82 if (uio->uio_rw != UIO_READ) 83 panic("nfs_read mode"); 84 #endif 85 if (uio->uio_resid == 0) 86 return (0); 87 if (uio->uio_offset < 0 && vp->v_type != VDIR) 88 return (EINVAL); 89 biosize = VFSTONFS(vp->v_mount)->nm_rsize; 90 /* 91 * If the file's modify time on the server has changed since the 92 * last read rpc or you have written to the file, 93 * you may have lost data cache consistency with the 94 * server, so flush all of the file's data out of the cache. 95 * Then force a getattr rpc to ensure that you have up to date 96 * attributes. 97 * NB: This implies that cache data can be read when up to 98 * NFS_ATTRTIMEO seconds out of date. If you find that you need current 99 * attributes this could be forced by setting n_attrstamp to 0 before 100 * the nfs_dogetattr() call. 101 */ 102 if (vp->v_type != VLNK) { 103 if (np->n_flag & NMODIFIED) { 104 np->n_flag &= ~NMODIFIED; 105 vinvalbuf(vp, TRUE); 106 np->n_attrstamp = 0; 107 np->n_direofoffset = 0; 108 if (error = nfs_dogetattr(vp, &vattr, cred, 1, 109 uio->uio_procp)) 110 return (error); 111 np->n_mtime = vattr.va_mtime.tv_sec; 112 } else { 113 if (error = nfs_dogetattr(vp, &vattr, cred, 1, 114 uio->uio_procp)) 115 return (error); 116 if (np->n_mtime != vattr.va_mtime.tv_sec) { 117 np->n_direofoffset = 0; 118 vinvalbuf(vp, TRUE); 119 np->n_mtime = vattr.va_mtime.tv_sec; 120 } 121 } 122 } 123 do { 124 switch (vp->v_type) { 125 case VREG: 126 nfsstats.biocache_reads++; 127 lbn = uio->uio_offset / biosize; 128 on = uio->uio_offset & (biosize-1); 129 n = MIN((unsigned)(biosize - on), uio->uio_resid); 130 diff = np->n_size - uio->uio_offset; 131 if (diff <= 0) 132 return (error); 133 if (diff < n) 134 n = diff; 135 bn = lbn*(biosize/DEV_BSIZE); 136 rablock = (lbn+1)*(biosize/DEV_BSIZE); 137 if (vp->v_lastr + 1 == lbn && 138 np->n_size > (rablock * DEV_BSIZE)) 139 error = breada(vp, bn, biosize, rablock, biosize, 140 cred, &bp); 141 else 142 error = bread(vp, bn, biosize, cred, &bp); 143 vp->v_lastr = lbn; 144 if (bp->b_resid) { 145 diff = (on >= (biosize-bp->b_resid)) ? 0 : 146 (biosize-bp->b_resid-on); 147 n = MIN(n, diff); 148 } 149 break; 150 case VLNK: 151 nfsstats.biocache_readlinks++; 152 on = 0; 153 error = bread(vp, (daddr_t)0, NFS_MAXPATHLEN, cred, &bp); 154 n = MIN(uio->uio_resid, NFS_MAXPATHLEN - bp->b_resid); 155 break; 156 case VDIR: 157 nfsstats.biocache_readdirs++; 158 on = 0; 159 error = bread(vp, uio->uio_offset, NFS_DIRBLKSIZ, cred, &bp); 160 n = MIN(uio->uio_resid, NFS_DIRBLKSIZ - bp->b_resid); 161 break; 162 }; 163 if (error) { 164 brelse(bp); 165 return (error); 166 } 167 if (n > 0) 168 error = uiomove(bp->b_un.b_addr + on, (int)n, uio); 169 switch (vp->v_type) { 170 case VREG: 171 if (n+on == biosize || uio->uio_offset == np->n_size) 172 bp->b_flags |= B_AGE; 173 break; 174 case VLNK: 175 n = 0; 176 break; 177 case VDIR: 178 uio->uio_offset = bp->b_blkno; 179 break; 180 }; 181 brelse(bp); 182 } while (error == 0 && uio->uio_resid > 0 && n != 0); 183 return (error); 184 } 185 186 /* 187 * Vnode op for write using bio 188 */ 189 nfs_write(vp, uio, ioflag, cred) 190 register struct vnode *vp; 191 register struct uio *uio; 192 int ioflag; 193 struct ucred *cred; 194 { 195 struct proc *p = uio->uio_procp; 196 register int biosize; 197 struct buf *bp; 198 struct nfsnode *np = VTONFS(vp); 199 struct vattr vattr; 200 daddr_t lbn, bn; 201 int n, on, error = 0; 202 203 #ifdef DIAGNOSTIC 204 if (uio->uio_rw != UIO_WRITE) 205 panic("nfs_write mode"); 206 if (uio->uio_segflg == UIO_USERSPACE && uio->uio_procp != curproc) 207 panic("nfs_write proc"); 208 #endif 209 if (vp->v_type != VREG) 210 return (EIO); 211 /* Should we try and do this ?? */ 212 if (ioflag & (IO_APPEND | IO_SYNC)) { 213 if (np->n_flag & NMODIFIED) { 214 np->n_flag &= ~NMODIFIED; 215 vinvalbuf(vp, TRUE); 216 } 217 if (ioflag & IO_APPEND) { 218 np->n_attrstamp = 0; 219 if (error = nfs_dogetattr(vp, &vattr, cred, 1, p)) 220 return (error); 221 uio->uio_offset = np->n_size; 222 } 223 return (nfs_writerpc(vp, uio, cred)); 224 } 225 #ifdef notdef 226 cnt = uio->uio_resid; 227 osize = np->n_size; 228 #endif 229 if (uio->uio_offset < 0) 230 return (EINVAL); 231 if (uio->uio_resid == 0) 232 return (0); 233 /* 234 * Maybe this should be above the vnode op call, but so long as 235 * file servers have no limits, i don't think it matters 236 */ 237 if (p && 238 uio->uio_offset + uio->uio_resid > 239 p->p_rlimit[RLIMIT_FSIZE].rlim_cur) { 240 psignal(p, SIGXFSZ); 241 return (EFBIG); 242 } 243 /* 244 * I use nm_rsize, not nm_wsize so that all buffer cache blocks 245 * will be the same size within a filesystem. nfs_writerpc will 246 * still use nm_wsize when sizing the rpc's. 247 */ 248 biosize = VFSTONFS(vp->v_mount)->nm_rsize; 249 np->n_flag |= NMODIFIED; 250 vnode_pager_uncache(vp); 251 do { 252 nfsstats.biocache_writes++; 253 lbn = uio->uio_offset / biosize; 254 on = uio->uio_offset & (biosize-1); 255 n = MIN((unsigned)(biosize - on), uio->uio_resid); 256 if (uio->uio_offset+n > np->n_size) { 257 np->n_size = uio->uio_offset+n; 258 vnode_pager_setsize(vp, np->n_size); 259 } 260 bn = lbn*(biosize/DEV_BSIZE); 261 again: 262 bp = getblk(vp, bn, biosize); 263 if (bp->b_wcred == NOCRED && cred != NOCRED) { 264 crhold(cred); 265 bp->b_wcred = cred; 266 } 267 if (bp->b_dirtyend > 0) { 268 /* 269 * If the new write will leave a contiguous dirty 270 * area, just update the b_dirtyoff and b_dirtyend, 271 * otherwise force a write rpc of the old dirty area. 272 */ 273 if (on <= bp->b_dirtyend && (on+n) >= bp->b_dirtyoff) { 274 bp->b_dirtyoff = MIN(on, bp->b_dirtyoff); 275 bp->b_dirtyend = MAX((on+n), bp->b_dirtyend); 276 } else { 277 bp->b_proc = p; 278 if (error = bwrite(bp)) 279 return (error); 280 goto again; 281 } 282 } else { 283 bp->b_dirtyoff = on; 284 bp->b_dirtyend = on+n; 285 } 286 if (error = uiomove(bp->b_un.b_addr + on, n, uio)) { 287 brelse(bp); 288 return (error); 289 } 290 if ((n+on) == biosize) { 291 bp->b_flags |= B_AGE; 292 bp->b_proc = (struct proc *)0; 293 bawrite(bp); 294 } else { 295 bp->b_proc = (struct proc *)0; 296 bdwrite(bp); 297 } 298 } while (error == 0 && uio->uio_resid > 0 && n != 0); 299 #ifdef notdef 300 /* Should we try and do this for nfs ?? */ 301 if (error && (ioflag & IO_UNIT)) { 302 np->n_size = osize; 303 uio->uio_offset -= cnt - uio->uio_resid; 304 uio->uio_resid = cnt; 305 } 306 #endif 307 return (error); 308 } 309