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 https://opensource.org/licenses/CDDL-1.0. 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 (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved. 23 * Copyright (c) 2011, 2020 by Delphix. All rights reserved. 24 */ 25 26 #include <sys/zfs_context.h> 27 #include <sys/spa.h> 28 #include <sys/spa_impl.h> 29 #include <sys/vdev_file.h> 30 #include <sys/vdev_impl.h> 31 #include <sys/vdev_trim.h> 32 #include <sys/zio.h> 33 #include <sys/fs/zfs.h> 34 #include <sys/fm/fs/zfs.h> 35 #include <sys/abd.h> 36 #include <sys/fcntl.h> 37 #include <sys/vnode.h> 38 #include <sys/zfs_file.h> 39 #ifdef _KERNEL 40 #include <linux/falloc.h> 41 #endif 42 /* 43 * Virtual device vector for files. 44 */ 45 46 static taskq_t *vdev_file_taskq; 47 48 /* 49 * By default, the logical/physical ashift for file vdevs is set to 50 * SPA_MINBLOCKSHIFT (9). This allows all file vdevs to use 512B (1 << 9) 51 * blocksizes. Users may opt to change one or both of these for testing 52 * or performance reasons. Care should be taken as these values will 53 * impact the vdev_ashift setting which can only be set at vdev creation 54 * time. 55 */ 56 static uint_t vdev_file_logical_ashift = SPA_MINBLOCKSHIFT; 57 static uint_t vdev_file_physical_ashift = SPA_MINBLOCKSHIFT; 58 59 static void 60 vdev_file_hold(vdev_t *vd) 61 { 62 ASSERT(vd->vdev_path != NULL); 63 } 64 65 static void 66 vdev_file_rele(vdev_t *vd) 67 { 68 ASSERT(vd->vdev_path != NULL); 69 } 70 71 static mode_t 72 vdev_file_open_mode(spa_mode_t spa_mode) 73 { 74 mode_t mode = 0; 75 76 if ((spa_mode & SPA_MODE_READ) && (spa_mode & SPA_MODE_WRITE)) { 77 mode = O_RDWR; 78 } else if (spa_mode & SPA_MODE_READ) { 79 mode = O_RDONLY; 80 } else if (spa_mode & SPA_MODE_WRITE) { 81 mode = O_WRONLY; 82 } 83 84 return (mode | O_LARGEFILE); 85 } 86 87 static int 88 vdev_file_open(vdev_t *vd, uint64_t *psize, uint64_t *max_psize, 89 uint64_t *logical_ashift, uint64_t *physical_ashift) 90 { 91 vdev_file_t *vf; 92 zfs_file_t *fp; 93 zfs_file_attr_t zfa; 94 int error; 95 96 /* 97 * Rotational optimizations only make sense on block devices. 98 */ 99 vd->vdev_nonrot = B_TRUE; 100 101 /* 102 * Allow TRIM on file based vdevs. This may not always be supported, 103 * since it depends on your kernel version and underlying filesystem 104 * type but it is always safe to attempt. 105 */ 106 vd->vdev_has_trim = B_TRUE; 107 108 /* 109 * Disable secure TRIM on file based vdevs. There is no way to 110 * request this behavior from the underlying filesystem. 111 */ 112 vd->vdev_has_securetrim = B_FALSE; 113 114 /* 115 * We must have a pathname, and it must be absolute. 116 */ 117 if (vd->vdev_path == NULL || vd->vdev_path[0] != '/') { 118 vd->vdev_stat.vs_aux = VDEV_AUX_BAD_LABEL; 119 return (SET_ERROR(EINVAL)); 120 } 121 122 /* 123 * Reopen the device if it's not currently open. Otherwise, 124 * just update the physical size of the device. 125 */ 126 if (vd->vdev_tsd != NULL) { 127 ASSERT(vd->vdev_reopening); 128 vf = vd->vdev_tsd; 129 goto skip_open; 130 } 131 132 vf = vd->vdev_tsd = kmem_zalloc(sizeof (vdev_file_t), KM_SLEEP); 133 134 /* 135 * We always open the files from the root of the global zone, even if 136 * we're in a local zone. If the user has gotten to this point, the 137 * administrator has already decided that the pool should be available 138 * to local zone users, so the underlying devices should be as well. 139 */ 140 ASSERT(vd->vdev_path != NULL && vd->vdev_path[0] == '/'); 141 142 error = zfs_file_open(vd->vdev_path, 143 vdev_file_open_mode(spa_mode(vd->vdev_spa)), 0, &fp); 144 if (error) { 145 vd->vdev_stat.vs_aux = VDEV_AUX_OPEN_FAILED; 146 return (error); 147 } 148 149 vf->vf_file = fp; 150 151 #ifdef _KERNEL 152 /* 153 * Make sure it's a regular file. 154 */ 155 if (zfs_file_getattr(fp, &zfa)) { 156 return (SET_ERROR(ENODEV)); 157 } 158 if (!S_ISREG(zfa.zfa_mode)) { 159 vd->vdev_stat.vs_aux = VDEV_AUX_OPEN_FAILED; 160 return (SET_ERROR(ENODEV)); 161 } 162 #endif 163 164 skip_open: 165 166 error = zfs_file_getattr(vf->vf_file, &zfa); 167 if (error) { 168 vd->vdev_stat.vs_aux = VDEV_AUX_OPEN_FAILED; 169 return (error); 170 } 171 172 *max_psize = *psize = zfa.zfa_size; 173 *logical_ashift = vdev_file_logical_ashift; 174 *physical_ashift = vdev_file_physical_ashift; 175 176 return (0); 177 } 178 179 static void 180 vdev_file_close(vdev_t *vd) 181 { 182 vdev_file_t *vf = vd->vdev_tsd; 183 184 if (vd->vdev_reopening || vf == NULL) 185 return; 186 187 if (vf->vf_file != NULL) { 188 (void) zfs_file_close(vf->vf_file); 189 } 190 191 vd->vdev_delayed_close = B_FALSE; 192 kmem_free(vf, sizeof (vdev_file_t)); 193 vd->vdev_tsd = NULL; 194 } 195 196 static void 197 vdev_file_io_strategy(void *arg) 198 { 199 zio_t *zio = (zio_t *)arg; 200 vdev_t *vd = zio->io_vd; 201 vdev_file_t *vf = vd->vdev_tsd; 202 ssize_t resid; 203 void *buf; 204 loff_t off; 205 ssize_t size; 206 int err; 207 208 off = zio->io_offset; 209 size = zio->io_size; 210 resid = 0; 211 212 if (zio->io_type == ZIO_TYPE_READ) { 213 buf = abd_borrow_buf(zio->io_abd, zio->io_size); 214 err = zfs_file_pread(vf->vf_file, buf, size, off, &resid); 215 abd_return_buf_copy(zio->io_abd, buf, size); 216 } else { 217 buf = abd_borrow_buf_copy(zio->io_abd, zio->io_size); 218 err = zfs_file_pwrite(vf->vf_file, buf, size, off, &resid); 219 abd_return_buf(zio->io_abd, buf, size); 220 } 221 zio->io_error = err; 222 if (resid != 0 && zio->io_error == 0) 223 zio->io_error = SET_ERROR(ENOSPC); 224 225 zio_delay_interrupt(zio); 226 } 227 228 static void 229 vdev_file_io_fsync(void *arg) 230 { 231 zio_t *zio = (zio_t *)arg; 232 vdev_file_t *vf = zio->io_vd->vdev_tsd; 233 234 zio->io_error = zfs_file_fsync(vf->vf_file, O_SYNC | O_DSYNC); 235 236 zio_interrupt(zio); 237 } 238 239 static void 240 vdev_file_io_start(zio_t *zio) 241 { 242 vdev_t *vd = zio->io_vd; 243 vdev_file_t *vf = vd->vdev_tsd; 244 245 if (zio->io_type == ZIO_TYPE_IOCTL) { 246 /* XXPOLICY */ 247 if (!vdev_readable(vd)) { 248 zio->io_error = SET_ERROR(ENXIO); 249 zio_interrupt(zio); 250 return; 251 } 252 253 switch (zio->io_cmd) { 254 case DKIOCFLUSHWRITECACHE: 255 256 if (zfs_nocacheflush) 257 break; 258 259 /* 260 * We cannot safely call vfs_fsync() when PF_FSTRANS 261 * is set in the current context. Filesystems like 262 * XFS include sanity checks to verify it is not 263 * already set, see xfs_vm_writepage(). Therefore 264 * the sync must be dispatched to a different context. 265 */ 266 if (__spl_pf_fstrans_check()) { 267 VERIFY3U(taskq_dispatch(vdev_file_taskq, 268 vdev_file_io_fsync, zio, TQ_SLEEP), !=, 269 TASKQID_INVALID); 270 return; 271 } 272 273 zio->io_error = zfs_file_fsync(vf->vf_file, 274 O_SYNC | O_DSYNC); 275 break; 276 default: 277 zio->io_error = SET_ERROR(ENOTSUP); 278 } 279 280 zio_execute(zio); 281 return; 282 } else if (zio->io_type == ZIO_TYPE_TRIM) { 283 int mode = 0; 284 285 ASSERT3U(zio->io_size, !=, 0); 286 #ifdef __linux__ 287 mode = FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE; 288 #endif 289 zio->io_error = zfs_file_fallocate(vf->vf_file, 290 mode, zio->io_offset, zio->io_size); 291 zio_execute(zio); 292 return; 293 } 294 295 zio->io_target_timestamp = zio_handle_io_delay(zio); 296 297 VERIFY3U(taskq_dispatch(vdev_file_taskq, vdev_file_io_strategy, zio, 298 TQ_SLEEP), !=, TASKQID_INVALID); 299 } 300 301 static void 302 vdev_file_io_done(zio_t *zio) 303 { 304 (void) zio; 305 } 306 307 vdev_ops_t vdev_file_ops = { 308 .vdev_op_init = NULL, 309 .vdev_op_fini = NULL, 310 .vdev_op_open = vdev_file_open, 311 .vdev_op_close = vdev_file_close, 312 .vdev_op_asize = vdev_default_asize, 313 .vdev_op_min_asize = vdev_default_min_asize, 314 .vdev_op_min_alloc = NULL, 315 .vdev_op_io_start = vdev_file_io_start, 316 .vdev_op_io_done = vdev_file_io_done, 317 .vdev_op_state_change = NULL, 318 .vdev_op_need_resilver = NULL, 319 .vdev_op_hold = vdev_file_hold, 320 .vdev_op_rele = vdev_file_rele, 321 .vdev_op_remap = NULL, 322 .vdev_op_xlate = vdev_default_xlate, 323 .vdev_op_rebuild_asize = NULL, 324 .vdev_op_metaslab_init = NULL, 325 .vdev_op_config_generate = NULL, 326 .vdev_op_nparity = NULL, 327 .vdev_op_ndisks = NULL, 328 .vdev_op_type = VDEV_TYPE_FILE, /* name of this vdev type */ 329 .vdev_op_leaf = B_TRUE /* leaf vdev */ 330 }; 331 332 void 333 vdev_file_init(void) 334 { 335 vdev_file_taskq = taskq_create("z_vdev_file", MAX(boot_ncpus, 16), 336 minclsyspri, boot_ncpus, INT_MAX, TASKQ_DYNAMIC); 337 338 VERIFY(vdev_file_taskq); 339 } 340 341 void 342 vdev_file_fini(void) 343 { 344 taskq_destroy(vdev_file_taskq); 345 } 346 347 /* 348 * From userland we access disks just like files. 349 */ 350 #ifndef _KERNEL 351 352 vdev_ops_t vdev_disk_ops = { 353 .vdev_op_init = NULL, 354 .vdev_op_fini = NULL, 355 .vdev_op_open = vdev_file_open, 356 .vdev_op_close = vdev_file_close, 357 .vdev_op_asize = vdev_default_asize, 358 .vdev_op_min_asize = vdev_default_min_asize, 359 .vdev_op_min_alloc = NULL, 360 .vdev_op_io_start = vdev_file_io_start, 361 .vdev_op_io_done = vdev_file_io_done, 362 .vdev_op_state_change = NULL, 363 .vdev_op_need_resilver = NULL, 364 .vdev_op_hold = vdev_file_hold, 365 .vdev_op_rele = vdev_file_rele, 366 .vdev_op_remap = NULL, 367 .vdev_op_xlate = vdev_default_xlate, 368 .vdev_op_rebuild_asize = NULL, 369 .vdev_op_metaslab_init = NULL, 370 .vdev_op_config_generate = NULL, 371 .vdev_op_nparity = NULL, 372 .vdev_op_ndisks = NULL, 373 .vdev_op_type = VDEV_TYPE_DISK, /* name of this vdev type */ 374 .vdev_op_leaf = B_TRUE /* leaf vdev */ 375 }; 376 377 #endif 378 379 ZFS_MODULE_PARAM(zfs_vdev_file, vdev_file_, logical_ashift, UINT, ZMOD_RW, 380 "Logical ashift for file-based devices"); 381 ZFS_MODULE_PARAM(zfs_vdev_file, vdev_file_, physical_ashift, UINT, ZMOD_RW, 382 "Physical ashift for file-based devices"); 383