geom_slice.c revision 93250
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 93250 2002-03-26 22:07:38Z 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, M_WAITOK | M_ZERO); 69 gsp->softc = g_malloc(scsize, M_WAITOK | M_ZERO); 70 gsp->slices = g_malloc(nslice * sizeof(struct g_slice), M_WAITOK | M_ZERO); 71 gsp->nslice = nslice; 72 return (gsp); 73} 74 75int 76g_slice_access(struct g_provider *pp, int dr, int dw, int de) 77{ 78 int error, i; 79 struct g_geom *gp; 80 struct g_consumer *cp; 81 struct g_provider *pp2; 82 struct g_slicer *gsp; 83 struct g_slice *gsl, *gsl2; 84 85 gp = pp->geom; 86 cp = LIST_FIRST(&gp->consumer); 87 KASSERT (cp != NULL, ("g_slice_access but no consumer")); 88 gsp = gp->softc; 89 gsl = &gsp->slices[pp->index]; 90 for (i = 0; i < gsp->nslice; i++) { 91 gsl2 = &gsp->slices[i]; 92 if (gsl2->length == 0) 93 continue; 94 if (i == pp->index) 95 continue; 96 if (gsl->offset + gsl->length <= gsl2->offset) 97 continue; 98 if (gsl2->offset + gsl2->length <= gsl->offset) 99 continue; 100 /* overlap */ 101 pp2 = gsl2->provider; 102 if ((pp->acw + dw) > 0 && pp2->ace > 0) 103 return (EPERM); 104 if ((pp->ace + de) > 0 && pp2->acw > 0) 105 return (EPERM); 106 } 107 /* On first open, grab an extra "exclusive" bit */ 108 if (cp->acr == 0 && cp->acw == 0 && cp->ace == 0) 109 de++; 110 /* ... and let go of it on last close */ 111 if ((cp->acr + dr) == 0 && (cp->acw + dw) == 0 && (cp->ace + de) == 1) 112 de--; 113 error = g_access_rel(cp, dr, dw, de); 114 return (error); 115} 116 117void 118g_slice_start(struct bio *bp) 119{ 120 struct bio *bp2; 121 struct g_provider *pp; 122 struct g_geom *gp; 123 struct g_consumer *cp; 124 struct g_slicer *gsp; 125 struct g_slice *gsl; 126 int index; 127 128 pp = bp->bio_to; 129 gp = pp->geom; 130 gsp = gp->softc; 131 cp = LIST_FIRST(&gp->consumer); 132 index = pp->index; 133 switch(bp->bio_cmd) { 134 case BIO_READ: 135 case BIO_WRITE: 136 case BIO_DELETE: 137 gsl = &gsp->slices[index]; 138 if (bp->bio_offset > gsl->length) { 139 bp->bio_error = EINVAL; /* XXX: EWHAT ? */ 140 g_io_deliver(bp); 141 return; 142 } 143 bp2 = g_clone_bio(bp); 144 if (bp2->bio_offset + bp2->bio_length > gsl->length) 145 bp2->bio_length = gsl->length - bp2->bio_offset; 146 bp2->bio_done = g_std_done; 147 bp2->bio_offset += gsl->offset; 148 g_io_request(bp2, cp); 149 return; 150 case BIO_GETATTR: 151 case BIO_SETATTR: 152 if (g_haveattr_off_t(bp, "GEOM::mediasize", 153 gsp->slices[index].length)) 154 return; 155 if (gsp->start(bp)) 156 return; 157 bp2 = g_clone_bio(bp); 158 bp2->bio_done = g_std_done; 159 g_io_request(bp2, cp); 160 break; 161 default: 162 bp->bio_error = EOPNOTSUPP; 163 g_io_deliver(bp); 164 return; 165 } 166} 167 168void 169g_slice_dumpconf(struct sbuf *sb, char *indent, struct g_geom *gp, struct g_consumer *cp __unused, struct g_provider *pp) 170{ 171 struct g_mbr_softc *mp; 172 struct g_slicer *gsp; 173 174 gsp = gp->softc; 175 mp = gsp->softc; 176 if (pp != NULL) { 177 sbuf_printf(sb, "%s<index>%u</index>\n", indent, pp->index); 178 sbuf_printf(sb, "%s<length>%llu</length>\n", 179 indent, gsp->slices[pp->index].length); 180 sbuf_printf(sb, "%s<seclength>%llu</seclength>\n", 181 indent, gsp->slices[pp->index].length / 512); 182 sbuf_printf(sb, "%s<offset>%llu</offset>\n", 183 indent, gsp->slices[pp->index].offset); 184 sbuf_printf(sb, "%s<secoffset>%llu</secoffset>\n", 185 indent, gsp->slices[pp->index].offset / 512); 186 } 187} 188 189struct g_provider * 190g_slice_addslice(struct g_geom *gp, int index, off_t offset, off_t length, char *fmt, ...) 191{ 192 struct g_provider *pp; 193 struct g_slicer *gsp; 194 va_list ap; 195 struct sbuf *sb; 196 197 g_trace(G_T_TOPOLOGY, "g_slice_addslice()"); 198 g_topology_lock(); 199 gsp = gp->softc; 200 va_start(ap, fmt); 201 sb = sbuf_new(NULL, NULL, 0, SBUF_AUTOEXTEND); 202 sbuf_vprintf(sb, fmt, ap); 203 sbuf_finish(sb); 204 pp = g_new_providerf(gp, sbuf_data(sb)); 205 206 pp->index = index; 207 gsp->slices[index].length = length; 208 gsp->slices[index].offset = offset; 209 gsp->slices[index].provider = pp; 210 sbuf_delete(sb); 211 g_topology_unlock(); 212 return(pp); 213} 214 215struct g_geom * 216g_slice_new(struct g_class *mp, int slices, struct g_provider *pp, struct g_consumer **cpp, void *extrap, int extra, g_slice_start_t *start) 217{ 218 struct g_geom *gp; 219 struct g_slicer *gsp; 220 struct g_consumer *cp; 221 void **vp; 222 int error; 223 224 g_topology_assert(); 225 vp = (void **)extrap; 226 gp = g_new_geomf(mp, "%s", pp->name); 227 gsp = g_slice_init(slices, extra); 228 gsp->start = start; 229 gp->softc = gsp; 230 gp->start = g_slice_start; 231 gp->spoiled = g_std_spoiled; 232 gp->dumpconf = g_slice_dumpconf; 233 cp = g_new_consumer(gp); 234 g_attach(cp, pp); 235 error = g_access_rel(cp, 1, 0, 0); 236 if (error) { 237 g_dettach(cp); 238 g_destroy_consumer(cp); 239 g_free(gsp->slices); 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) 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} 270