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, 2015 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 35 /* 36 * Virtual device vector for files. 37 */ 38 39 static void 40 vdev_file_hold(vdev_t *vd) 41 { 42 ASSERT(vd->vdev_path != NULL); 43 } 44 45 static void 46 vdev_file_rele(vdev_t *vd) 47 { 48 ASSERT(vd->vdev_path != NULL); 49 } 50 51 static int 52 vdev_file_open(vdev_t *vd, uint64_t *psize, uint64_t *max_psize, 53 uint64_t *ashift) 54 { 55 vdev_file_t *vf; 56 vnode_t *vp; 57 vattr_t vattr; 58 int error; 59 60 /* 61 * We must have a pathname, and it must be absolute. 62 */ 63 if (vd->vdev_path == NULL || vd->vdev_path[0] != '/') { 64 vd->vdev_stat.vs_aux = VDEV_AUX_BAD_LABEL; 65 return (SET_ERROR(EINVAL)); 66 } 67 68 /* 69 * Reopen the device if it's not currently open. Otherwise, 70 * just update the physical size of the device. 71 */ 72 if (vd->vdev_tsd != NULL) { 73 ASSERT(vd->vdev_reopening); 74 vf = vd->vdev_tsd; 75 goto skip_open; 76 } 77 78 vf = vd->vdev_tsd = kmem_zalloc(sizeof (vdev_file_t), KM_SLEEP); 79 80 /* 81 * We always open the files from the root of the global zone, even if 82 * we're in a local zone. If the user has gotten to this point, the 83 * administrator has already decided that the pool should be available 84 * to local zone users, so the underlying devices should be as well. 85 */ 86 ASSERT(vd->vdev_path != NULL && vd->vdev_path[0] == '/'); 87 error = vn_openat(vd->vdev_path + 1, UIO_SYSSPACE, 88 spa_mode(vd->vdev_spa) | FOFFMAX, 0, &vp, 0, 0, rootdir, -1); 89 90 if (error) { 91 vd->vdev_stat.vs_aux = VDEV_AUX_OPEN_FAILED; 92 return (error); 93 } 94 95 vf->vf_vnode = vp; 96 97 #ifdef _KERNEL 98 /* 99 * Make sure it's a regular file. 100 */ 101 if (vp->v_type != VREG) { 102 vd->vdev_stat.vs_aux = VDEV_AUX_OPEN_FAILED; 103 return (SET_ERROR(ENODEV)); 104 } 105 #endif 106 107 skip_open: 108 /* 109 * Determine the physical size of the file. 110 */ 111 vattr.va_mask = AT_SIZE; 112 error = VOP_GETATTR(vf->vf_vnode, &vattr, 0, kcred, NULL); 113 if (error) { 114 vd->vdev_stat.vs_aux = VDEV_AUX_OPEN_FAILED; 115 return (error); 116 } 117 118 *max_psize = *psize = vattr.va_size; 119 *ashift = SPA_MINBLOCKSHIFT; 120 121 return (0); 122 } 123 124 static void 125 vdev_file_close(vdev_t *vd) 126 { 127 vdev_file_t *vf = vd->vdev_tsd; 128 129 if (vd->vdev_reopening || vf == NULL) 130 return; 131 132 if (vf->vf_vnode != NULL) { 133 (void) VOP_PUTPAGE(vf->vf_vnode, 0, 0, B_INVAL, kcred, NULL); 134 (void) VOP_CLOSE(vf->vf_vnode, spa_mode(vd->vdev_spa), 1, 0, 135 kcred, NULL); 136 VN_RELE(vf->vf_vnode); 137 } 138 139 vd->vdev_delayed_close = B_FALSE; 140 kmem_free(vf, sizeof (vdev_file_t)); 141 vd->vdev_tsd = NULL; 142 } 143 144 /* 145 * Implements the interrupt side for file vdev types. This routine will be 146 * called when the I/O completes allowing us to transfer the I/O to the 147 * interrupt taskqs. For consistency, the code structure mimics disk vdev 148 * types. 149 */ 150 static void 151 vdev_file_io_intr(buf_t *bp) 152 { 153 vdev_buf_t *vb = (vdev_buf_t *)bp; 154 zio_t *zio = vb->vb_io; 155 156 zio->io_error = (geterror(bp) != 0 ? EIO : 0); 157 if (zio->io_error == 0 && bp->b_resid != 0) 158 zio->io_error = SET_ERROR(ENOSPC); 159 160 kmem_free(vb, sizeof (vdev_buf_t)); 161 zio_delay_interrupt(zio); 162 } 163 164 static void 165 vdev_file_io_strategy(void *arg) 166 { 167 buf_t *bp = arg; 168 vnode_t *vp = bp->b_private; 169 ssize_t resid; 170 int error; 171 172 error = vn_rdwr((bp->b_flags & B_READ) ? UIO_READ : UIO_WRITE, 173 vp, bp->b_un.b_addr, bp->b_bcount, ldbtob(bp->b_lblkno), 174 UIO_SYSSPACE, 0, RLIM64_INFINITY, kcred, &resid); 175 176 if (error == 0) { 177 bp->b_resid = resid; 178 biodone(bp); 179 } else { 180 bioerror(bp, error); 181 biodone(bp); 182 } 183 } 184 185 static void 186 vdev_file_io_start(zio_t *zio) 187 { 188 vdev_t *vd = zio->io_vd; 189 vdev_file_t *vf = vd->vdev_tsd; 190 vdev_buf_t *vb; 191 buf_t *bp; 192 193 if (zio->io_type == ZIO_TYPE_IOCTL) { 194 /* XXPOLICY */ 195 if (!vdev_readable(vd)) { 196 zio->io_error = SET_ERROR(ENXIO); 197 zio_interrupt(zio); 198 return; 199 } 200 201 switch (zio->io_cmd) { 202 case DKIOCFLUSHWRITECACHE: 203 zio->io_error = VOP_FSYNC(vf->vf_vnode, FSYNC | FDSYNC, 204 kcred, NULL); 205 break; 206 default: 207 zio->io_error = SET_ERROR(ENOTSUP); 208 } 209 210 zio_execute(zio); 211 return; 212 } 213 214 ASSERT(zio->io_type == ZIO_TYPE_READ || zio->io_type == ZIO_TYPE_WRITE); 215 zio->io_target_timestamp = zio_handle_io_delay(zio); 216 217 vb = kmem_alloc(sizeof (vdev_buf_t), KM_SLEEP); 218 219 vb->vb_io = zio; 220 bp = &vb->vb_buf; 221 222 bioinit(bp); 223 bp->b_flags = (zio->io_type == ZIO_TYPE_READ ? B_READ : B_WRITE); 224 bp->b_bcount = zio->io_size; 225 bp->b_un.b_addr = zio->io_data; 226 bp->b_lblkno = lbtodb(zio->io_offset); 227 bp->b_bufsize = zio->io_size; 228 bp->b_private = vf->vf_vnode; 229 bp->b_iodone = (int (*)())vdev_file_io_intr; 230 231 VERIFY3U(taskq_dispatch(system_taskq, vdev_file_io_strategy, bp, 232 TQ_SLEEP), !=, 0); 233 } 234 235 /* ARGSUSED */ 236 static void 237 vdev_file_io_done(zio_t *zio) 238 { 239 } 240 241 vdev_ops_t vdev_file_ops = { 242 vdev_file_open, 243 vdev_file_close, 244 vdev_default_asize, 245 vdev_file_io_start, 246 vdev_file_io_done, 247 NULL, 248 vdev_file_hold, 249 vdev_file_rele, 250 VDEV_TYPE_FILE, /* name of this vdev type */ 251 B_TRUE /* leaf vdev */ 252 }; 253 254 /* 255 * From userland we access disks just like files. 256 */ 257 #ifndef _KERNEL 258 259 vdev_ops_t vdev_disk_ops = { 260 vdev_file_open, 261 vdev_file_close, 262 vdev_default_asize, 263 vdev_file_io_start, 264 vdev_file_io_done, 265 NULL, 266 vdev_file_hold, 267 vdev_file_rele, 268 VDEV_TYPE_DISK, /* name of this vdev type */ 269 B_TRUE /* leaf vdev */ 270 }; 271 272 #endif 273