1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 /* 22 * Copyright 2006 Sun Microsystems, Inc. All rights reserved. 23 * Use is subject to license terms. 24 */ 25 26 #pragma ident "%Z%%M% %I% %E% SMI" 27 28 #include <sys/zfs_context.h> 29 #include <sys/spa.h> 30 #include <sys/vdev_disk.h> 31 #include <sys/vdev_impl.h> 32 #include <sys/fs/zfs.h> 33 #include <sys/zio.h> 34 #include <sys/sunldi.h> 35 36 /* 37 * Virtual device vector for disks. 38 */ 39 40 /* 41 * Tunable parameter for debugging or performance analysis. Setting 42 * zfs_nocacheflush will cause corruption on power loss if a volatile 43 * out-of-order write cache is enabled. 44 */ 45 boolean_t zfs_nocacheflush = B_FALSE; 46 47 extern ldi_ident_t zfs_li; 48 49 typedef struct vdev_disk_buf { 50 buf_t vdb_buf; 51 zio_t *vdb_io; 52 } vdev_disk_buf_t; 53 54 static int 55 vdev_disk_open(vdev_t *vd, uint64_t *psize, uint64_t *ashift) 56 { 57 vdev_disk_t *dvd; 58 struct dk_minfo dkm; 59 int error; 60 61 /* 62 * We must have a pathname, and it must be absolute. 63 */ 64 if (vd->vdev_path == NULL || vd->vdev_path[0] != '/') { 65 vd->vdev_stat.vs_aux = VDEV_AUX_BAD_LABEL; 66 return (EINVAL); 67 } 68 69 dvd = vd->vdev_tsd = kmem_zalloc(sizeof (vdev_disk_t), KM_SLEEP); 70 71 /* 72 * When opening a disk device, we want to preserve the user's original 73 * intent. We always want to open the device by the path the user gave 74 * us, even if it is one of multiple paths to the save device. But we 75 * also want to be able to survive disks being removed/recabled. 76 * Therefore the sequence of opening devices is: 77 * 78 * 1. Try opening the device by path. For legacy pools without the 79 * 'whole_disk' property, attempt to fix the path by appending 's0'. 80 * 81 * 2. If the devid of the device matches the stored value, return 82 * success. 83 * 84 * 3. Otherwise, the device may have moved. Try opening the device 85 * by the devid instead. 86 * 87 */ 88 if (vd->vdev_devid != NULL) { 89 if (ddi_devid_str_decode(vd->vdev_devid, &dvd->vd_devid, 90 &dvd->vd_minor) != 0) { 91 vd->vdev_stat.vs_aux = VDEV_AUX_BAD_LABEL; 92 return (EINVAL); 93 } 94 } 95 96 error = EINVAL; /* presume failure */ 97 98 if (vd->vdev_path != NULL) { 99 ddi_devid_t devid; 100 101 if (vd->vdev_wholedisk == -1ULL) { 102 size_t len = strlen(vd->vdev_path) + 3; 103 char *buf = kmem_alloc(len, KM_SLEEP); 104 ldi_handle_t lh; 105 106 (void) snprintf(buf, len, "%ss0", vd->vdev_path); 107 108 if (ldi_open_by_name(buf, spa_mode, kcred, 109 &lh, zfs_li) == 0) { 110 spa_strfree(vd->vdev_path); 111 vd->vdev_path = buf; 112 vd->vdev_wholedisk = 1ULL; 113 (void) ldi_close(lh, spa_mode, kcred); 114 } else { 115 kmem_free(buf, len); 116 } 117 } 118 119 error = ldi_open_by_name(vd->vdev_path, spa_mode, kcred, 120 &dvd->vd_lh, zfs_li); 121 122 /* 123 * Compare the devid to the stored value. 124 */ 125 if (error == 0 && vd->vdev_devid != NULL && 126 ldi_get_devid(dvd->vd_lh, &devid) == 0) { 127 if (ddi_devid_compare(devid, dvd->vd_devid) != 0) { 128 error = EINVAL; 129 (void) ldi_close(dvd->vd_lh, spa_mode, kcred); 130 dvd->vd_lh = NULL; 131 } 132 ddi_devid_free(devid); 133 } 134 135 /* 136 * If we succeeded in opening the device, but 'vdev_wholedisk' 137 * is not yet set, then this must be a slice. 138 */ 139 if (error == 0 && vd->vdev_wholedisk == -1ULL) 140 vd->vdev_wholedisk = 0; 141 } 142 143 /* 144 * If we were unable to open by path, or the devid check fails, open by 145 * devid instead. 146 */ 147 if (error != 0 && vd->vdev_devid != NULL) 148 error = ldi_open_by_devid(dvd->vd_devid, dvd->vd_minor, 149 spa_mode, kcred, &dvd->vd_lh, zfs_li); 150 151 if (error) { 152 vd->vdev_stat.vs_aux = VDEV_AUX_OPEN_FAILED; 153 return (error); 154 } 155 156 /* 157 * Determine the actual size of the device. 158 */ 159 if (ldi_get_size(dvd->vd_lh, psize) != 0) { 160 vd->vdev_stat.vs_aux = VDEV_AUX_OPEN_FAILED; 161 return (EINVAL); 162 } 163 164 /* 165 * If we own the whole disk, try to enable disk write caching. 166 * We ignore errors because it's OK if we can't do it. 167 */ 168 if (vd->vdev_wholedisk == 1) { 169 int wce = 1; 170 (void) ldi_ioctl(dvd->vd_lh, DKIOCSETWCE, (intptr_t)&wce, 171 FKIOCTL, kcred, NULL); 172 } 173 174 /* 175 * Determine the device's minimum transfer size. 176 * If the ioctl isn't supported, assume DEV_BSIZE. 177 */ 178 if (ldi_ioctl(dvd->vd_lh, DKIOCGMEDIAINFO, (intptr_t)&dkm, 179 FKIOCTL, kcred, NULL) != 0) 180 dkm.dki_lbsize = DEV_BSIZE; 181 182 *ashift = highbit(MAX(dkm.dki_lbsize, SPA_MINBLOCKSIZE)) - 1; 183 184 /* 185 * Clear the nowritecache bit, so that on a vdev_reopen() we will 186 * try again. 187 */ 188 vd->vdev_nowritecache = B_FALSE; 189 190 return (0); 191 } 192 193 static void 194 vdev_disk_close(vdev_t *vd) 195 { 196 vdev_disk_t *dvd = vd->vdev_tsd; 197 198 if (dvd == NULL) 199 return; 200 201 dprintf("removing disk %s, devid %s\n", 202 vd->vdev_path ? vd->vdev_path : "<none>", 203 vd->vdev_devid ? vd->vdev_devid : "<none>"); 204 205 if (dvd->vd_minor != NULL) 206 ddi_devid_str_free(dvd->vd_minor); 207 208 if (dvd->vd_devid != NULL) 209 ddi_devid_free(dvd->vd_devid); 210 211 if (dvd->vd_lh != NULL) 212 (void) ldi_close(dvd->vd_lh, spa_mode, kcred); 213 214 kmem_free(dvd, sizeof (vdev_disk_t)); 215 vd->vdev_tsd = NULL; 216 } 217 218 static void 219 vdev_disk_io_intr(buf_t *bp) 220 { 221 vdev_disk_buf_t *vdb = (vdev_disk_buf_t *)bp; 222 zio_t *zio = vdb->vdb_io; 223 224 if ((zio->io_error = geterror(bp)) == 0 && bp->b_resid != 0) 225 zio->io_error = EIO; 226 227 kmem_free(vdb, sizeof (vdev_disk_buf_t)); 228 229 zio_next_stage_async(zio); 230 } 231 232 static void 233 vdev_disk_ioctl_done(void *zio_arg, int error) 234 { 235 zio_t *zio = zio_arg; 236 237 zio->io_error = error; 238 239 zio_next_stage_async(zio); 240 } 241 242 static void 243 vdev_disk_io_start(zio_t *zio) 244 { 245 vdev_t *vd = zio->io_vd; 246 vdev_disk_t *dvd = vd->vdev_tsd; 247 vdev_disk_buf_t *vdb; 248 buf_t *bp; 249 int flags, error; 250 251 if (zio->io_type == ZIO_TYPE_IOCTL) { 252 zio_vdev_io_bypass(zio); 253 254 /* XXPOLICY */ 255 if (vdev_is_dead(vd)) { 256 zio->io_error = ENXIO; 257 zio_next_stage_async(zio); 258 return; 259 } 260 261 switch (zio->io_cmd) { 262 263 case DKIOCFLUSHWRITECACHE: 264 265 if (zfs_nocacheflush) 266 break; 267 268 if (vd->vdev_nowritecache) { 269 zio->io_error = ENOTSUP; 270 break; 271 } 272 273 zio->io_dk_callback.dkc_callback = vdev_disk_ioctl_done; 274 zio->io_dk_callback.dkc_cookie = zio; 275 276 error = ldi_ioctl(dvd->vd_lh, zio->io_cmd, 277 (uintptr_t)&zio->io_dk_callback, 278 FKIOCTL, kcred, NULL); 279 280 if (error == 0) { 281 /* 282 * The ioctl will be done asychronously, 283 * and will call vdev_disk_ioctl_done() 284 * upon completion. 285 */ 286 return; 287 } else if (error == ENOTSUP) { 288 /* 289 * If we get ENOTSUP, we know that no future 290 * attempts will ever succeed. In this case we 291 * set a persistent bit so that we don't bother 292 * with the ioctl in the future. 293 */ 294 vd->vdev_nowritecache = B_TRUE; 295 } 296 zio->io_error = error; 297 298 break; 299 300 default: 301 zio->io_error = ENOTSUP; 302 } 303 304 zio_next_stage_async(zio); 305 return; 306 } 307 308 if (zio->io_type == ZIO_TYPE_READ && vdev_cache_read(zio) == 0) 309 return; 310 311 if ((zio = vdev_queue_io(zio)) == NULL) 312 return; 313 314 flags = (zio->io_type == ZIO_TYPE_READ ? B_READ : B_WRITE); 315 flags |= B_BUSY | B_NOCACHE; 316 if (zio->io_flags & ZIO_FLAG_FAILFAST) 317 flags |= B_FAILFAST; 318 319 vdb = kmem_alloc(sizeof (vdev_disk_buf_t), KM_SLEEP); 320 321 vdb->vdb_io = zio; 322 bp = &vdb->vdb_buf; 323 324 bioinit(bp); 325 bp->b_flags = flags; 326 bp->b_bcount = zio->io_size; 327 bp->b_un.b_addr = zio->io_data; 328 bp->b_lblkno = lbtodb(zio->io_offset); 329 bp->b_bufsize = zio->io_size; 330 bp->b_iodone = (int (*)())vdev_disk_io_intr; 331 332 /* XXPOLICY */ 333 error = vdev_is_dead(vd) ? ENXIO : vdev_error_inject(vd, zio); 334 if (error) { 335 zio->io_error = error; 336 bioerror(bp, error); 337 bp->b_resid = bp->b_bcount; 338 bp->b_iodone(bp); 339 return; 340 } 341 342 error = ldi_strategy(dvd->vd_lh, bp); 343 /* ldi_strategy() will return non-zero only on programming errors */ 344 ASSERT(error == 0); 345 } 346 347 static void 348 vdev_disk_io_done(zio_t *zio) 349 { 350 vdev_queue_io_done(zio); 351 352 if (zio->io_type == ZIO_TYPE_WRITE) 353 vdev_cache_write(zio); 354 355 if (zio_injection_enabled && zio->io_error == 0) 356 zio->io_error = zio_handle_device_injection(zio->io_vd, EIO); 357 358 zio_next_stage(zio); 359 } 360 361 vdev_ops_t vdev_disk_ops = { 362 vdev_disk_open, 363 vdev_disk_close, 364 vdev_default_asize, 365 vdev_disk_io_start, 366 vdev_disk_io_done, 367 NULL, 368 VDEV_TYPE_DISK, /* name of this vdev type */ 369 B_TRUE /* leaf vdev */ 370 }; 371