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 * @(#)nfs_bio.c 7.19 (Berkeley) 4/16/91 37 */ 38 39 #include "param.h" 40 #include "proc.h" 41 #include "buf.h" 42 #include "uio.h" 43 #include "namei.h" 44 #include "vnode.h" 45 #include "trace.h" 46 #include "mount.h" 47 #include "resourcevar.h" 48 49 #include "nfsnode.h" 50 #include "nfsv2.h" 51 #include "nfs.h" 52 #include "nfsiom.h" 53 #include "nfsmount.h" 54 55 /* True and false, how exciting */ 56 #define TRUE 1 57 #define FALSE 0 58 59 /* 60 * Vnode op for read using bio 61 * Any similarity to readip() is purely coincidental 62 */ 63 nfs_bioread(vp, uio, ioflag, cred) 64 register struct vnode *vp; 65 register struct uio *uio; 66 int ioflag; 67 struct ucred *cred; 68 { 69 register struct nfsnode *np = VTONFS(vp); 70 register int biosize; 71 struct buf *bp; 72 struct vattr vattr; 73 daddr_t lbn, bn, rablock; 74 int diff, error = 0; 75 long n, on; 76 77 #ifdef lint 78 ioflag = ioflag; 79 #endif /* lint */ 80 #ifdef DIAGNOSTIC 81 if (uio->uio_rw != UIO_READ) 82 panic("nfs_read mode"); 83 #endif 84 if (uio->uio_resid == 0) 85 return (0); 86 if (uio->uio_offset < 0 && vp->v_type != VDIR) 87 return (EINVAL); 88 biosize = VFSTONFS(vp->v_mount)->nm_rsize; 89 /* 90 * If the file's modify time on the server has changed since the 91 * last read rpc or you have written to the file, 92 * you may have lost data cache consistency with the 93 * server, so flush all of the file's data out of the cache. 94 * Then force a getattr rpc to ensure that you have up to date 95 * attributes. 96 * NB: This implies that cache data can be read when up to 97 * NFS_ATTRTIMEO seconds out of date. If you find that you need current 98 * attributes this could be forced by setting n_attrstamp to 0 before 99 * the nfs_dogetattr() call. 100 */ 101 if (vp->v_type != VLNK) { 102 if (np->n_flag & NMODIFIED) { 103 np->n_flag &= ~NMODIFIED; 104 vinvalbuf(vp, TRUE); 105 np->n_attrstamp = 0; 106 np->n_direofoffset = 0; 107 if (error = nfs_dogetattr(vp, &vattr, cred, 1, 108 uio->uio_procp)) 109 return (error); 110 np->n_mtime = vattr.va_mtime.tv_sec; 111 } else { 112 if (error = nfs_dogetattr(vp, &vattr, cred, 1, 113 uio->uio_procp)) 114 return (error); 115 if (np->n_mtime != vattr.va_mtime.tv_sec) { 116 np->n_direofoffset = 0; 117 vinvalbuf(vp, TRUE); 118 np->n_mtime = vattr.va_mtime.tv_sec; 119 } 120 } 121 } 122 do { 123 switch (vp->v_type) { 124 case VREG: 125 nfsstats.biocache_reads++; 126 lbn = uio->uio_offset / biosize; 127 on = uio->uio_offset & (biosize-1); 128 n = MIN((unsigned)(biosize - on), uio->uio_resid); 129 diff = np->n_size - uio->uio_offset; 130 if (diff <= 0) 131 return (error); 132 if (diff < n) 133 n = diff; 134 bn = lbn*(biosize/DEV_BSIZE); 135 rablock = (lbn+1)*(biosize/DEV_BSIZE); 136 if (vp->v_lastr + 1 == lbn && 137 np->n_size > (rablock * DEV_BSIZE)) 138 error = breada(vp, bn, biosize, rablock, biosize, 139 cred, &bp); 140 else 141 error = bread(vp, bn, biosize, cred, &bp); 142 vp->v_lastr = lbn; 143 if (bp->b_resid) { 144 diff = (on >= (biosize-bp->b_resid)) ? 0 : 145 (biosize-bp->b_resid-on); 146 n = MIN(n, diff); 147 } 148 break; 149 case VLNK: 150 nfsstats.biocache_readlinks++; 151 on = 0; 152 error = bread(vp, (daddr_t)0, NFS_MAXPATHLEN, cred, &bp); 153 n = MIN(uio->uio_resid, NFS_MAXPATHLEN - bp->b_resid); 154 break; 155 case VDIR: 156 nfsstats.biocache_readdirs++; 157 on = 0; 158 error = bread(vp, uio->uio_offset, NFS_DIRBLKSIZ, cred, &bp); 159 n = MIN(uio->uio_resid, NFS_DIRBLKSIZ - bp->b_resid); 160 break; 161 }; 162 if (error) { 163 brelse(bp); 164 return (error); 165 } 166 if (n > 0) 167 error = uiomove(bp->b_un.b_addr + on, (int)n, uio); 168 switch (vp->v_type) { 169 case VREG: 170 if (n+on == biosize || uio->uio_offset == np->n_size) 171 bp->b_flags |= B_AGE; 172 break; 173 case VLNK: 174 n = 0; 175 break; 176 case VDIR: 177 uio->uio_offset = bp->b_blkno; 178 break; 179 }; 180 brelse(bp); 181 } while (error == 0 && uio->uio_resid > 0 && n != 0); 182 return (error); 183 } 184 185 /* 186 * Vnode op for write using bio 187 */ 188 nfs_write(vp, uio, ioflag, cred) 189 register struct vnode *vp; 190 register struct uio *uio; 191 int ioflag; 192 struct ucred *cred; 193 { 194 struct proc *p = uio->uio_procp; 195 register int biosize; 196 struct buf *bp; 197 struct nfsnode *np = VTONFS(vp); 198 struct vattr vattr; 199 daddr_t lbn, bn; 200 int n, on, error = 0; 201 202 #ifdef DIAGNOSTIC 203 if (uio->uio_rw != UIO_WRITE) 204 panic("nfs_write mode"); 205 if (uio->uio_segflg == UIO_USERSPACE && uio->uio_procp != curproc) 206 panic("nfs_write proc"); 207 #endif 208 if (vp->v_type != VREG) 209 return (EIO); 210 /* Should we try and do this ?? */ 211 if (ioflag & (IO_APPEND | IO_SYNC)) { 212 if (np->n_flag & NMODIFIED) { 213 np->n_flag &= ~NMODIFIED; 214 vinvalbuf(vp, TRUE); 215 } 216 if (ioflag & IO_APPEND) { 217 np->n_attrstamp = 0; 218 if (error = nfs_dogetattr(vp, &vattr, cred, 1, p)) 219 return (error); 220 uio->uio_offset = np->n_size; 221 } 222 return (nfs_writerpc(vp, uio, cred)); 223 } 224 #ifdef notdef 225 cnt = uio->uio_resid; 226 osize = np->n_size; 227 #endif 228 if (uio->uio_offset < 0) 229 return (EINVAL); 230 if (uio->uio_resid == 0) 231 return (0); 232 /* 233 * Maybe this should be above the vnode op call, but so long as 234 * file servers have no limits, i don't think it matters 235 */ 236 if (uio->uio_offset + uio->uio_resid > 237 p->p_rlimit[RLIMIT_FSIZE].rlim_cur) { 238 psignal(p, SIGXFSZ); 239 return (EFBIG); 240 } 241 /* 242 * I use nm_rsize, not nm_wsize so that all buffer cache blocks 243 * will be the same size within a filesystem. nfs_writerpc will 244 * still use nm_wsize when sizing the rpc's. 245 */ 246 biosize = VFSTONFS(vp->v_mount)->nm_rsize; 247 np->n_flag |= NMODIFIED; 248 do { 249 nfsstats.biocache_writes++; 250 lbn = uio->uio_offset / biosize; 251 on = uio->uio_offset & (biosize-1); 252 n = MIN((unsigned)(biosize - on), uio->uio_resid); 253 if (uio->uio_offset+n > np->n_size) { 254 np->n_size = uio->uio_offset+n; 255 vnode_pager_setsize(vp, np->n_size); 256 } 257 bn = lbn*(biosize/DEV_BSIZE); 258 again: 259 bp = getblk(vp, bn, biosize); 260 if (bp->b_wcred == NOCRED) { 261 crhold(cred); 262 bp->b_wcred = cred; 263 } 264 if (bp->b_dirtyend > 0) { 265 /* 266 * If the new write will leave a contiguous dirty 267 * area, just update the b_dirtyoff and b_dirtyend, 268 * otherwise force a write rpc of the old dirty area. 269 */ 270 if (on <= bp->b_dirtyend && (on+n) >= bp->b_dirtyoff) { 271 bp->b_dirtyoff = MIN(on, bp->b_dirtyoff); 272 bp->b_dirtyend = MAX((on+n), bp->b_dirtyend); 273 } else { 274 bp->b_proc = p; 275 if (error = bwrite(bp)) 276 return (error); 277 goto again; 278 } 279 } else { 280 bp->b_dirtyoff = on; 281 bp->b_dirtyend = on+n; 282 } 283 if (error = uiomove(bp->b_un.b_addr + on, n, uio)) { 284 brelse(bp); 285 return (error); 286 } 287 if ((n+on) == biosize) { 288 bp->b_flags |= B_AGE; 289 bp->b_proc = (struct proc *)0; 290 bawrite(bp); 291 } else { 292 bp->b_proc = (struct proc *)0; 293 bdwrite(bp); 294 } 295 } while (error == 0 && uio->uio_resid > 0 && n != 0); 296 #ifdef notdef 297 /* Should we try and do this for nfs ?? */ 298 if (error && (ioflag & IO_UNIT)) { 299 np->n_size = osize; 300 uio->uio_offset -= cnt - uio->uio_resid; 301 uio->uio_resid = cnt; 302 } 303 #endif 304 return (error); 305 } 306