geom_slice.c revision 92108
1/*- 2 * Copyright (c) 2002 Poul-Henning Kamp 3 * Copyright (c) 2002 Networks Associates Technology, Inc. 4 * All rights reserved. 5 * 6 * This software was developed for the FreeBSD Project by Poul-Henning Kamp 7 * and NAI Labs, the Security Research Division of Network Associates, Inc. 8 * under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), as part of the 9 * DARPA CHATS research program. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 3. The names of the authors may not be used to endorse or promote 20 * products derived from this software without specific prior written 21 * permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 * 35 * $FreeBSD: head/sys/geom/geom_slice.c 92108 2002-03-11 21:42:35Z phk $ 36 */ 37 38 39#include <sys/param.h> 40#ifndef _KERNEL 41#include <stdio.h> 42#include <unistd.h> 43#include <stdlib.h> 44#include <signal.h> 45#include <err.h> 46#else 47#include <sys/systm.h> 48#include <sys/kernel.h> 49#include <sys/malloc.h> 50#include <sys/bio.h> 51#include <sys/sysctl.h> 52#include <sys/proc.h> 53#include <sys/kthread.h> 54#include <sys/lock.h> 55#include <sys/mutex.h> 56#endif 57#include <sys/errno.h> 58#include <sys/sbuf.h> 59#include <geom/geom.h> 60#include <geom/geom_slice.h> 61#include <machine/stdarg.h> 62 63struct g_slicer * 64g_slice_init(unsigned nslice, unsigned scsize) 65{ 66 struct g_slicer *gsp; 67 68 gsp = g_malloc(sizeof *gsp + nslice * sizeof(struct g_slice) + scsize, 69 M_WAITOK | M_ZERO); 70 gsp->softc = gsp + 1; 71 gsp->slices = (struct g_slice *)((u_char *)gsp->softc + scsize); 72 gsp->nslice = nslice; 73 return (gsp); 74} 75 76int 77g_slice_access(struct g_provider *pp, int dr, int dw, int de) 78{ 79 int error, i; 80 struct g_geom *gp; 81 struct g_consumer *cp; 82 struct g_provider *pp2; 83 struct g_slicer *gsp; 84 struct g_slice *gsl, *gsl2; 85 86 gp = pp->geom; 87 cp = LIST_FIRST(&gp->consumer); 88 KASSERT (cp != NULL, ("g_slice_access but no consumer")); 89 gsp = gp->softc; 90 gsl = &gsp->slices[pp->index]; 91 for (i = 0; i < gsp->nslice; i++) { 92 gsl2 = &gsp->slices[i]; 93 if (gsl2->length == 0) 94 continue; 95 if (i == pp->index) 96 continue; 97 if (gsl->offset + gsl->length <= gsl2->offset) 98 continue; 99 if (gsl2->offset + gsl2->length <= gsl->offset) 100 continue; 101 /* overlap */ 102 pp2 = gsl2->provider; 103 if ((pp->acw + dw) > 0 && pp2->ace > 0) 104 return (EPERM); 105 if ((pp->ace + de) > 0 && pp2->acw > 0) 106 return (EPERM); 107 } 108 /* On first open, grab an extra "exclusive" bit */ 109 if (cp->acr == 0 && cp->acw == 0 && cp->ace == 0) 110 de++; 111 /* ... and let go of it on last close */ 112 if ((cp->acr + dr) == 0 && (cp->acw + dw) == 0 && (cp->ace + de) == 1) 113 de--; 114 error = g_access_rel(cp, dr, dw, de); 115 return (error); 116} 117 118void 119g_slice_start(struct bio *bp) 120{ 121 struct bio *bp2; 122 struct g_provider *pp; 123 struct g_geom *gp; 124 struct g_consumer *cp; 125 struct g_slicer *gsp; 126 struct g_slice *gsl; 127 int index; 128 129 pp = bp->bio_to; 130 gp = pp->geom; 131 gsp = gp->softc; 132 cp = LIST_FIRST(&gp->consumer); 133 index = pp->index; 134 switch(bp->bio_cmd) { 135 case BIO_READ: 136 case BIO_WRITE: 137 case BIO_DELETE: 138 gsl = &gsp->slices[index]; 139 if (bp->bio_offset > gsl->length) { 140 bp->bio_error = EINVAL; /* XXX: EWHAT ? */ 141 g_io_deliver(bp); 142 return; 143 } 144 bp2 = g_clone_bio(bp); 145 if (bp2->bio_offset + bp2->bio_length > gsl->length) 146 bp2->bio_length = gsl->length - bp2->bio_offset; 147 bp2->bio_done = g_std_done; 148 bp2->bio_offset += gsl->offset; 149 g_io_request(bp2, cp); 150 return; 151 case BIO_GETATTR: 152 case BIO_SETATTR: 153 if (g_haveattr_off_t(bp, "GEOM::mediasize", 154 gsp->slices[index].length)) 155 return; 156 if (gsp->start(bp)) 157 return; 158 bp2 = g_clone_bio(bp); 159 bp2->bio_done = g_std_done; 160 g_io_request(bp2, cp); 161 break; 162 default: 163 bp->bio_error = EOPNOTSUPP; 164 g_io_deliver(bp); 165 return; 166 } 167} 168 169void 170g_slice_dumpconf(struct sbuf *sb, char *indent, struct g_geom *gp, struct g_consumer *cp __unused, struct g_provider *pp) 171{ 172 struct g_mbr_softc *mp; 173 struct g_slicer *gsp; 174 175 gsp = gp->softc; 176 mp = gsp->softc; 177 if (pp != NULL) { 178 sbuf_printf(sb, "%s<index>%u</index>\n", indent, pp->index); 179 sbuf_printf(sb, "%s<length>%llu</length>\n", 180 indent, gsp->slices[pp->index].length); 181 sbuf_printf(sb, "%s<seclength>%llu</seclength>\n", 182 indent, gsp->slices[pp->index].length / 512); 183 sbuf_printf(sb, "%s<offset>%llu</offset>\n", 184 indent, gsp->slices[pp->index].offset); 185 sbuf_printf(sb, "%s<secoffset>%llu</secoffset>\n", 186 indent, gsp->slices[pp->index].offset / 512); 187 } 188} 189 190struct g_provider * 191g_slice_addslice(struct g_geom *gp, int index, off_t offset, off_t length, char *fmt, ...) 192{ 193 struct g_provider *pp; 194 struct g_slicer *gsp; 195 va_list ap; 196 struct sbuf *sb; 197 198 g_trace(G_T_TOPOLOGY, "g_slice_addslice()"); 199 g_topology_lock(); 200 gsp = gp->softc; 201 va_start(ap, fmt); 202 sb = sbuf_new(NULL, NULL, 0, SBUF_AUTOEXTEND); 203 sbuf_vprintf(sb, fmt, ap); 204 sbuf_finish(sb); 205 pp = g_new_providerf(gp, sbuf_data(sb)); 206 207 pp->index = index; 208 gsp->slices[index].length = length; 209 gsp->slices[index].offset = offset; 210 gsp->slices[index].provider = pp; 211 sbuf_delete(sb); 212 g_topology_unlock(); 213 return(pp); 214} 215 216struct g_geom * 217g_slice_new(struct g_method *mp, int slices, struct g_provider *pp, struct g_consumer **cpp, void *extrap, int extra, g_slice_start_t *start) 218{ 219 struct g_geom *gp; 220 struct g_slicer *gsp; 221 struct g_consumer *cp; 222 void **vp; 223 int error; 224 225 g_topology_assert(); 226 vp = (void **)extrap; 227 gp = g_new_geomf(mp, "%s", pp->name); 228 gsp = g_slice_init(slices, extra); 229 gsp->start = start; 230 gp->softc = gsp; 231 gp->start = g_slice_start; 232 gp->spoiled = g_std_spoiled; 233 gp->dumpconf = g_slice_dumpconf; 234 cp = g_new_consumer(gp); 235 g_attach(cp, pp); 236 error = g_access_rel(cp, 1, 0, 0); 237 if (error) { 238 g_dettach(cp); 239 g_destroy_consumer(cp); 240 g_free(gp->softc); 241 g_destroy_geom(gp); 242 return (NULL); 243 } 244 *vp = gsp->softc; 245 *cpp = cp; 246 return (gp); 247} 248 249void 250g_slice_orphan(struct g_consumer *cp, struct thread *tp __unused) 251{ 252 struct g_geom *gp; 253 struct g_provider *pp; 254 int error; 255 256 g_trace(G_T_TOPOLOGY, "g_slice_orphan(%p/%s)", cp, cp->provider->name); 257 g_topology_assert(); 258 KASSERT(cp->provider->error != 0, 259 ("g_slice_orphan with error == 0")); 260 261 gp = cp->geom; 262 gp->flags |= G_GEOM_WITHER; 263 /* First prevent any new requests */ 264 error = cp->provider->error; 265 LIST_FOREACH(pp, &gp->provider, provider) 266 g_orphan_provider(pp, error); 267 268 return; 269 if (cp->biocount > 0) 270 return; 271 272 /* Then selfdestruct */ 273 if (cp->acr != 0 || cp->acw != 0 || cp->ace != 0) 274 g_access_abs(cp, 0, 0, 0); 275 g_dettach(cp); 276 g_destroy_consumer(cp); 277 return; 278} 279