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 1.11 1994/05/24 02:33:34 cgd Exp $ 38 */ 39 40 #include <sys/param.h> 41 #include <sys/systm.h> 42 #include <sys/proc.h> 43 #include <sys/buf.h> 44 #include <sys/uio.h> 45 #include <sys/namei.h> 46 #include <sys/vnode.h> 47 #include <sys/trace.h> 48 #include <sys/mount.h> 49 #include <sys/resourcevar.h> 50 51 #include <nfs/nfsnode.h> 52 #include <nfs/nfsv2.h> 53 #include <nfs/nfs.h> 54 #include <nfs/nfsiom.h> 55 #include <nfs/nfsmount.h> 56 57 /* True and false, how exciting */ 58 #define TRUE 1 59 #define FALSE 0 60 61 /* 62 * Vnode op for read using bio 63 * Any similarity to readip() is purely coincidental 64 */ 65 nfs_bioread(vp, uio, ioflag, cred) 66 register struct vnode *vp; 67 register struct uio *uio; 68 int ioflag; 69 struct ucred *cred; 70 { 71 register struct nfsnode *np = VTONFS(vp); 72 register int biosize; 73 struct buf *bp; 74 struct vattr vattr; 75 daddr_t lbn, bn, rablock; 76 int diff, error = 0; 77 long n, on; 78 79 #ifdef lint 80 ioflag = ioflag; 81 #endif /* lint */ 82 #ifdef DIAGNOSTIC 83 if (uio->uio_rw != UIO_READ) 84 panic("nfs_read mode"); 85 #endif 86 if (uio->uio_resid == 0) 87 return (0); 88 if (uio->uio_offset < 0 && vp->v_type != VDIR) 89 return (EINVAL); 90 biosize = VFSTONFS(vp->v_mount)->nm_rsize; 91 /* 92 * If the file's modify time on the server has changed since the 93 * last read rpc or you have written to the file, 94 * you may have lost data cache consistency with the 95 * server, so flush all of the file's data out of the cache. 96 * Then force a getattr rpc to ensure that you have up to date 97 * attributes. 98 * NB: This implies that cache data can be read when up to 99 * NFS_ATTRTIMEO seconds out of date. If you find that you need current 100 * attributes this could be forced by setting n_attrstamp to 0 before 101 * the nfs_dogetattr() call. 102 */ 103 if (vp->v_type != VLNK) { 104 if (np->n_flag & NMODIFIED) { 105 np->n_flag &= ~NMODIFIED; 106 vinvalbuf(vp, TRUE); 107 np->n_attrstamp = 0; 108 np->n_direofoffset = 0; 109 if (error = nfs_dogetattr(vp, &vattr, cred, 1, 110 uio->uio_procp)) 111 return (error); 112 np->n_mtime = vattr.va_mtime.ts_sec; 113 } else { 114 if (error = nfs_dogetattr(vp, &vattr, cred, 1, 115 uio->uio_procp)) 116 return (error); 117 if (np->n_mtime != vattr.va_mtime.ts_sec) { 118 np->n_direofoffset = 0; 119 vinvalbuf(vp, TRUE); 120 np->n_mtime = vattr.va_mtime.ts_sec; 121 } 122 } 123 } 124 do { 125 switch (vp->v_type) { 126 case VREG: 127 nfsstats.biocache_reads++; 128 lbn = uio->uio_offset / biosize; 129 on = uio->uio_offset & (biosize-1); 130 n = min((unsigned)(biosize - on), uio->uio_resid); 131 diff = np->n_size - uio->uio_offset; 132 if (diff <= 0) 133 return (error); 134 if (diff < n) 135 n = diff; 136 bn = lbn*(biosize/DEV_BSIZE); 137 rablock = (lbn+1)*(biosize/DEV_BSIZE); 138 if (vp->v_lastr + 1 == lbn && 139 np->n_size > (rablock * DEV_BSIZE)) 140 error = breada(vp, bn, biosize, rablock, biosize, 141 cred, &bp); 142 else 143 error = bread(vp, bn, biosize, cred, &bp); 144 vp->v_lastr = lbn; 145 if (bp->b_resid) { 146 diff = (on >= (biosize-bp->b_resid)) ? 0 : 147 (biosize-bp->b_resid-on); 148 n = min(n, diff); 149 } 150 break; 151 case VLNK: 152 nfsstats.biocache_readlinks++; 153 on = 0; 154 error = bread(vp, (daddr_t)0, NFS_MAXPATHLEN, cred, &bp); 155 n = min(uio->uio_resid, NFS_MAXPATHLEN - bp->b_resid); 156 break; 157 case VDIR: 158 nfsstats.biocache_readdirs++; 159 on = 0; 160 error = bread(vp, uio->uio_offset, NFS_DIRBLKSIZ, cred, &bp); 161 n = min(uio->uio_resid, NFS_DIRBLKSIZ - bp->b_resid); 162 break; 163 }; 164 if (error) { 165 brelse(bp); 166 return (error); 167 } 168 if (n > 0) 169 error = uiomove(bp->b_un.b_addr + on, (int)n, uio); 170 switch (vp->v_type) { 171 case VREG: 172 if (n+on == biosize || uio->uio_offset == np->n_size) 173 bp->b_flags |= B_AGE; 174 break; 175 case VLNK: 176 n = 0; 177 break; 178 case VDIR: 179 uio->uio_offset = bp->b_blkno; 180 break; 181 }; 182 brelse(bp); 183 } while (error == 0 && uio->uio_resid > 0 && n != 0); 184 return (error); 185 } 186 187 /* 188 * Vnode op for write using bio 189 */ 190 nfs_write(vp, uio, ioflag, cred) 191 register struct vnode *vp; 192 register struct uio *uio; 193 int ioflag; 194 struct ucred *cred; 195 { 196 struct proc *p = uio->uio_procp; 197 register int biosize; 198 struct buf *bp; 199 struct nfsnode *np = VTONFS(vp); 200 struct vattr vattr; 201 daddr_t lbn, bn; 202 int n, on, error = 0; 203 204 #ifdef DIAGNOSTIC 205 if (uio->uio_rw != UIO_WRITE) 206 panic("nfs_write mode"); 207 if (uio->uio_segflg == UIO_USERSPACE && uio->uio_procp != curproc) 208 panic("nfs_write proc"); 209 #endif 210 if (vp->v_type != VREG) 211 return (EIO); 212 /* Should we try and do this ?? */ 213 if (ioflag & (IO_APPEND | IO_SYNC)) { 214 if (np->n_flag & NMODIFIED) { 215 np->n_flag &= ~NMODIFIED; 216 vinvalbuf(vp, TRUE); 217 } 218 if (ioflag & IO_APPEND) { 219 np->n_attrstamp = 0; 220 if (error = nfs_dogetattr(vp, &vattr, cred, 1, p)) 221 return (error); 222 uio->uio_offset = np->n_size; 223 } 224 return (nfs_writerpc(vp, uio, cred)); 225 } 226 #ifdef notdef 227 cnt = uio->uio_resid; 228 osize = np->n_size; 229 #endif 230 if (uio->uio_offset < 0) 231 return (EINVAL); 232 if (uio->uio_resid == 0) 233 return (0); 234 /* 235 * Maybe this should be above the vnode op call, but so long as 236 * file servers have no limits, i don't think it matters 237 */ 238 if (p && 239 uio->uio_offset + uio->uio_resid > 240 p->p_rlimit[RLIMIT_FSIZE].rlim_cur) { 241 psignal(p, SIGXFSZ); 242 return (EFBIG); 243 } 244 /* 245 * I use nm_rsize, not nm_wsize so that all buffer cache blocks 246 * will be the same size within a filesystem. nfs_writerpc will 247 * still use nm_wsize when sizing the rpc's. 248 */ 249 biosize = VFSTONFS(vp->v_mount)->nm_rsize; 250 np->n_flag |= NMODIFIED; 251 vnode_pager_uncache(vp); 252 do { 253 nfsstats.biocache_writes++; 254 lbn = uio->uio_offset / biosize; 255 on = uio->uio_offset & (biosize-1); 256 n = min((unsigned)(biosize - on), uio->uio_resid); 257 if (uio->uio_offset+n > np->n_size) { 258 np->n_size = uio->uio_offset+n; 259 vnode_pager_setsize(vp, np->n_size); 260 } 261 bn = lbn*(biosize/DEV_BSIZE); 262 again: 263 bp = getblk(vp, bn, biosize, 0, 0); 264 if (bp->b_wcred == NOCRED && cred != NOCRED) { 265 crhold(cred); 266 bp->b_wcred = cred; 267 } 268 if (bp->b_dirtyend > 0) { 269 /* 270 * If the new write will leave a contiguous dirty 271 * area, just update the b_dirtyoff and b_dirtyend, 272 * otherwise force a write rpc of the old dirty area. 273 */ 274 if (on <= bp->b_dirtyend && (on+n) >= bp->b_dirtyoff) { 275 bp->b_dirtyoff = min(on, bp->b_dirtyoff); 276 bp->b_dirtyend = max((on+n), bp->b_dirtyend); 277 } else { 278 bp->b_proc = p; 279 if (error = bwrite(bp)) 280 return (error); 281 goto again; 282 } 283 } else { 284 bp->b_dirtyoff = on; 285 bp->b_dirtyend = on+n; 286 } 287 if (error = uiomove(bp->b_un.b_addr + on, n, uio)) { 288 brelse(bp); 289 return (error); 290 } 291 if ((n+on) == biosize) { 292 bp->b_flags |= B_AGE; 293 bp->b_proc = (struct proc *)0; 294 bawrite(bp); 295 } else { 296 bp->b_proc = (struct proc *)0; 297 bdwrite(bp); 298 } 299 } while (error == 0 && uio->uio_resid > 0 && n != 0); 300 #ifdef notdef 301 /* Should we try and do this for nfs ?? */ 302 if (error && (ioflag & IO_UNIT)) { 303 np->n_size = osize; 304 uio->uio_offset -= cnt - uio->uio_resid; 305 uio->uio_resid = cnt; 306 } 307 #endif 308 return (error); 309 } 310