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 (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved. 23 * Copyright (c) 2011, 2016 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/zio.h> 32 #include <sys/fs/zfs.h> 33 #include <sys/fm/fs/zfs.h> 34 #include <sys/abd.h> 35 36 /* 37 * Virtual device vector for files. 38 */ 39 40 static void 41 vdev_file_hold(vdev_t *vd) 42 { 43 ASSERT(vd->vdev_path != NULL); 44 } 45 46 static void 47 vdev_file_rele(vdev_t *vd) 48 { 49 ASSERT(vd->vdev_path != NULL); 50 } 51 52 static int 53 vdev_file_open(vdev_t *vd, uint64_t *psize, uint64_t *max_psize, 54 uint64_t *ashift) 55 { 56 vdev_file_t *vf; 57 vnode_t *vp; 58 vattr_t vattr; 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 (SET_ERROR(EINVAL)); 67 } 68 69 /* 70 * Reopen the device if it's not currently open. Otherwise, 71 * just update the physical size of the device. 72 */ 73 if (vd->vdev_tsd != NULL) { 74 ASSERT(vd->vdev_reopening); 75 vf = vd->vdev_tsd; 76 goto skip_open; 77 } 78 79 vf = vd->vdev_tsd = kmem_zalloc(sizeof (vdev_file_t), KM_SLEEP); 80 81 /* 82 * We always open the files from the root of the global zone, even if 83 * we're in a local zone. If the user has gotten to this point, the 84 * administrator has already decided that the pool should be available 85 * to local zone users, so the underlying devices should be as well. 86 */ 87 ASSERT(vd->vdev_path != NULL && vd->vdev_path[0] == '/'); 88 error = vn_openat(vd->vdev_path + 1, UIO_SYSSPACE, 89 spa_mode(vd->vdev_spa) | FOFFMAX, 0, &vp, 0, 0, rootdir, -1); 90 91 if (error) { 92 vd->vdev_stat.vs_aux = VDEV_AUX_OPEN_FAILED; 93 return (error); 94 } 95 96 vf->vf_vnode = vp; 97 98 #ifdef _KERNEL 99 /* 100 * Make sure it's a regular file. 101 */ 102 if (vp->v_type != VREG) { 103 vd->vdev_stat.vs_aux = VDEV_AUX_OPEN_FAILED; 104 return (SET_ERROR(ENODEV)); 105 } 106 #endif 107 108 skip_open: 109 /* 110 * Determine the physical size of the file. 111 */ 112 vattr.va_mask = AT_SIZE; 113 error = VOP_GETATTR(vf->vf_vnode, &vattr, 0, kcred, NULL); 114 if (error) { 115 vd->vdev_stat.vs_aux = VDEV_AUX_OPEN_FAILED; 116 return (error); 117 } 118 119 *max_psize = *psize = vattr.va_size; 120 *ashift = SPA_MINBLOCKSHIFT; 121 122 return (0); 123 } 124 125 static void 126 vdev_file_close(vdev_t *vd) 127 { 128 vdev_file_t *vf = vd->vdev_tsd; 129 130 if (vd->vdev_reopening || vf == NULL) 131 return; 132 133 if (vf->vf_vnode != NULL) { 134 (void) VOP_PUTPAGE(vf->vf_vnode, 0, 0, B_INVAL, kcred, NULL); 135 (void) VOP_CLOSE(vf->vf_vnode, spa_mode(vd->vdev_spa), 1, 0, 136 kcred, NULL); 137 VN_RELE(vf->vf_vnode); 138 } 139 140 vd->vdev_delayed_close = B_FALSE; 141 kmem_free(vf, sizeof (vdev_file_t)); 142 vd->vdev_tsd = NULL; 143 } 144 145 /* 146 * Implements the interrupt side for file vdev types. This routine will be 147 * called when the I/O completes allowing us to transfer the I/O to the 148 * interrupt taskqs. For consistency, the code structure mimics disk vdev 149 * types. 150 */ 151 static int 152 vdev_file_io_intr(buf_t *bp) 153 { 154 vdev_buf_t *vb = (vdev_buf_t *)bp; 155 zio_t *zio = vb->vb_io; 156 157 zio->io_error = (geterror(bp) != 0 ? EIO : 0); 158 if (zio->io_error == 0 && bp->b_resid != 0) 159 zio->io_error = SET_ERROR(ENOSPC); 160 161 if (zio->io_type == ZIO_TYPE_READ) { 162 abd_return_buf_copy(zio->io_abd, bp->b_un.b_addr, zio->io_size); 163 } else { 164 abd_return_buf(zio->io_abd, bp->b_un.b_addr, zio->io_size); 165 } 166 167 kmem_free(vb, sizeof (vdev_buf_t)); 168 zio_delay_interrupt(zio); 169 return (0); 170 } 171 172 static void 173 vdev_file_io_strategy(void *arg) 174 { 175 buf_t *bp = arg; 176 vnode_t *vp = bp->b_private; 177 ssize_t resid; 178 int error; 179 180 error = vn_rdwr((bp->b_flags & B_READ) ? UIO_READ : UIO_WRITE, 181 vp, bp->b_un.b_addr, bp->b_bcount, ldbtob(bp->b_lblkno), 182 UIO_SYSSPACE, 0, RLIM64_INFINITY, kcred, &resid); 183 184 if (error == 0) { 185 bp->b_resid = resid; 186 biodone(bp); 187 } else { 188 bioerror(bp, error); 189 biodone(bp); 190 } 191 } 192 193 static void 194 vdev_file_io_start(zio_t *zio) 195 { 196 vdev_t *vd = zio->io_vd; 197 vdev_file_t *vf = vd->vdev_tsd; 198 vdev_buf_t *vb; 199 buf_t *bp; 200 201 if (zio->io_type == ZIO_TYPE_IOCTL) { 202 /* XXPOLICY */ 203 if (!vdev_readable(vd)) { 204 zio->io_error = SET_ERROR(ENXIO); 205 zio_interrupt(zio); 206 return; 207 } 208 209 switch (zio->io_cmd) { 210 case DKIOCFLUSHWRITECACHE: 211 zio->io_error = VOP_FSYNC(vf->vf_vnode, FSYNC | FDSYNC, 212 kcred, NULL); 213 break; 214 default: 215 zio->io_error = SET_ERROR(ENOTSUP); 216 } 217 218 zio_execute(zio); 219 return; 220 } 221 222 ASSERT(zio->io_type == ZIO_TYPE_READ || zio->io_type == ZIO_TYPE_WRITE); 223 zio->io_target_timestamp = zio_handle_io_delay(zio); 224 225 vb = kmem_alloc(sizeof (vdev_buf_t), KM_SLEEP); 226 227 vb->vb_io = zio; 228 bp = &vb->vb_buf; 229 230 bioinit(bp); 231 bp->b_flags = (zio->io_type == ZIO_TYPE_READ ? B_READ : B_WRITE); 232 bp->b_bcount = zio->io_size; 233 234 if (zio->io_type == ZIO_TYPE_READ) { 235 bp->b_un.b_addr = 236 abd_borrow_buf(zio->io_abd, zio->io_size); 237 } else { 238 bp->b_un.b_addr = 239 abd_borrow_buf_copy(zio->io_abd, zio->io_size); 240 } 241 242 bp->b_lblkno = lbtodb(zio->io_offset); 243 bp->b_bufsize = zio->io_size; 244 bp->b_private = vf->vf_vnode; 245 bp->b_iodone = vdev_file_io_intr; 246 247 VERIFY3U(taskq_dispatch(system_taskq, vdev_file_io_strategy, bp, 248 TQ_SLEEP), !=, TASKQID_INVALID); 249 } 250 251 /* ARGSUSED */ 252 static void 253 vdev_file_io_done(zio_t *zio) 254 { 255 } 256 257 vdev_ops_t vdev_file_ops = { 258 .vdev_op_open = vdev_file_open, 259 .vdev_op_close = vdev_file_close, 260 .vdev_op_asize = vdev_default_asize, 261 .vdev_op_io_start = vdev_file_io_start, 262 .vdev_op_io_done = vdev_file_io_done, 263 .vdev_op_state_change = NULL, 264 .vdev_op_need_resilver = NULL, 265 .vdev_op_hold = vdev_file_hold, 266 .vdev_op_rele = vdev_file_rele, 267 .vdev_op_remap = NULL, 268 .vdev_op_xlate = vdev_default_xlate, 269 .vdev_op_type = VDEV_TYPE_FILE, /* name of this vdev type */ 270 .vdev_op_leaf = B_TRUE /* leaf vdev */ 271 }; 272 273 /* 274 * From userland we access disks just like files. 275 */ 276 #ifndef _KERNEL 277 278 vdev_ops_t vdev_disk_ops = { 279 .vdev_op_open = vdev_file_open, 280 .vdev_op_close = vdev_file_close, 281 .vdev_op_asize = vdev_default_asize, 282 .vdev_op_io_start = vdev_file_io_start, 283 .vdev_op_io_done = vdev_file_io_done, 284 .vdev_op_state_change = NULL, 285 .vdev_op_need_resilver = NULL, 286 .vdev_op_hold = vdev_file_hold, 287 .vdev_op_rele = vdev_file_rele, 288 .vdev_op_remap = NULL, 289 .vdev_op_xlate = vdev_default_xlate, 290 .vdev_op_type = VDEV_TYPE_DISK, /* name of this vdev type */ 291 .vdev_op_leaf = B_TRUE /* leaf vdev */ 292 }; 293 294 #endif 295