| 1 | /* $NetBSD: spec_vnops.c,v 1.165 2016/09/08 08:45:52 pgoyette Exp $ */ |
| 2 | |
| 3 | /*- |
| 4 | * Copyright (c) 2008 The NetBSD Foundation, Inc. |
| 5 | * All rights reserved. |
| 6 | * |
| 7 | * Redistribution and use in source and binary forms, with or without |
| 8 | * modification, are permitted provided that the following conditions |
| 9 | * are met: |
| 10 | * 1. Redistributions of source code must retain the above copyright |
| 11 | * notice, this list of conditions and the following disclaimer. |
| 12 | * 2. Redistributions in binary form must reproduce the above copyright |
| 13 | * notice, this list of conditions and the following disclaimer in the |
| 14 | * documentation and/or other materials provided with the distribution. |
| 15 | * |
| 16 | * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS |
| 17 | * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED |
| 18 | * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR |
| 19 | * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS |
| 20 | * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
| 21 | * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
| 22 | * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
| 23 | * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN |
| 24 | * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
| 25 | * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE |
| 26 | * POSSIBILITY OF SUCH DAMAGE. |
| 27 | */ |
| 28 | |
| 29 | /* |
| 30 | * Copyright (c) 1989, 1993 |
| 31 | * The Regents of the University of California. All rights reserved. |
| 32 | * |
| 33 | * Redistribution and use in source and binary forms, with or without |
| 34 | * modification, are permitted provided that the following conditions |
| 35 | * are met: |
| 36 | * 1. Redistributions of source code must retain the above copyright |
| 37 | * notice, this list of conditions and the following disclaimer. |
| 38 | * 2. Redistributions in binary form must reproduce the above copyright |
| 39 | * notice, this list of conditions and the following disclaimer in the |
| 40 | * documentation and/or other materials provided with the distribution. |
| 41 | * 3. Neither the name of the University nor the names of its contributors |
| 42 | * may be used to endorse or promote products derived from this software |
| 43 | * without specific prior written permission. |
| 44 | * |
| 45 | * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND |
| 46 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| 47 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| 48 | * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE |
| 49 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
| 50 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
| 51 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| 52 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
| 53 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
| 54 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| 55 | * SUCH DAMAGE. |
| 56 | * |
| 57 | * @(#)spec_vnops.c 8.15 (Berkeley) 7/14/95 |
| 58 | */ |
| 59 | |
| 60 | #include <sys/cdefs.h> |
| 61 | __KERNEL_RCSID(0, "$NetBSD: spec_vnops.c,v 1.165 2016/09/08 08:45:52 pgoyette Exp $" ); |
| 62 | |
| 63 | #include <sys/param.h> |
| 64 | #include <sys/proc.h> |
| 65 | #include <sys/systm.h> |
| 66 | #include <sys/kernel.h> |
| 67 | #include <sys/conf.h> |
| 68 | #include <sys/buf.h> |
| 69 | #include <sys/mount.h> |
| 70 | #include <sys/namei.h> |
| 71 | #include <sys/vnode.h> |
| 72 | #include <sys/stat.h> |
| 73 | #include <sys/errno.h> |
| 74 | #include <sys/ioctl.h> |
| 75 | #include <sys/poll.h> |
| 76 | #include <sys/file.h> |
| 77 | #include <sys/disklabel.h> |
| 78 | #include <sys/lockf.h> |
| 79 | #include <sys/tty.h> |
| 80 | #include <sys/kauth.h> |
| 81 | #include <sys/fstrans.h> |
| 82 | #include <sys/module.h> |
| 83 | |
| 84 | #include <miscfs/genfs/genfs.h> |
| 85 | #include <miscfs/specfs/specdev.h> |
| 86 | |
| 87 | /* symbolic sleep message strings for devices */ |
| 88 | const char devopn[] = "devopn" ; |
| 89 | const char devio[] = "devio" ; |
| 90 | const char devwait[] = "devwait" ; |
| 91 | const char devin[] = "devin" ; |
| 92 | const char devout[] = "devout" ; |
| 93 | const char devioc[] = "devioc" ; |
| 94 | const char devcls[] = "devcls" ; |
| 95 | |
| 96 | #define SPECHSZ 64 |
| 97 | #if ((SPECHSZ&(SPECHSZ-1)) == 0) |
| 98 | #define SPECHASH(rdev) (((rdev>>5)+(rdev))&(SPECHSZ-1)) |
| 99 | #else |
| 100 | #define SPECHASH(rdev) (((unsigned)((rdev>>5)+(rdev)))%SPECHSZ) |
| 101 | #endif |
| 102 | |
| 103 | static vnode_t *specfs_hash[SPECHSZ]; |
| 104 | extern struct mount *dead_rootmount; |
| 105 | |
| 106 | /* |
| 107 | * This vnode operations vector is used for special device nodes |
| 108 | * created from whole cloth by the kernel. For the ops vector for |
| 109 | * vnodes built from special devices found in a filesystem, see (e.g) |
| 110 | * ffs_specop_entries[] in ffs_vnops.c or the equivalent for other |
| 111 | * filesystems. |
| 112 | */ |
| 113 | |
| 114 | int (**spec_vnodeop_p)(void *); |
| 115 | const struct vnodeopv_entry_desc spec_vnodeop_entries[] = { |
| 116 | { &vop_default_desc, vn_default_error }, |
| 117 | { &vop_lookup_desc, spec_lookup }, /* lookup */ |
| 118 | { &vop_create_desc, spec_create }, /* create */ |
| 119 | { &vop_mknod_desc, spec_mknod }, /* mknod */ |
| 120 | { &vop_open_desc, spec_open }, /* open */ |
| 121 | { &vop_close_desc, spec_close }, /* close */ |
| 122 | { &vop_access_desc, spec_access }, /* access */ |
| 123 | { &vop_getattr_desc, spec_getattr }, /* getattr */ |
| 124 | { &vop_setattr_desc, spec_setattr }, /* setattr */ |
| 125 | { &vop_read_desc, spec_read }, /* read */ |
| 126 | { &vop_write_desc, spec_write }, /* write */ |
| 127 | { &vop_fallocate_desc, spec_fallocate }, /* fallocate */ |
| 128 | { &vop_fdiscard_desc, spec_fdiscard }, /* fdiscard */ |
| 129 | { &vop_fcntl_desc, spec_fcntl }, /* fcntl */ |
| 130 | { &vop_ioctl_desc, spec_ioctl }, /* ioctl */ |
| 131 | { &vop_poll_desc, spec_poll }, /* poll */ |
| 132 | { &vop_kqfilter_desc, spec_kqfilter }, /* kqfilter */ |
| 133 | { &vop_revoke_desc, spec_revoke }, /* revoke */ |
| 134 | { &vop_mmap_desc, spec_mmap }, /* mmap */ |
| 135 | { &vop_fsync_desc, spec_fsync }, /* fsync */ |
| 136 | { &vop_seek_desc, spec_seek }, /* seek */ |
| 137 | { &vop_remove_desc, spec_remove }, /* remove */ |
| 138 | { &vop_link_desc, spec_link }, /* link */ |
| 139 | { &vop_rename_desc, spec_rename }, /* rename */ |
| 140 | { &vop_mkdir_desc, spec_mkdir }, /* mkdir */ |
| 141 | { &vop_rmdir_desc, spec_rmdir }, /* rmdir */ |
| 142 | { &vop_symlink_desc, spec_symlink }, /* symlink */ |
| 143 | { &vop_readdir_desc, spec_readdir }, /* readdir */ |
| 144 | { &vop_readlink_desc, spec_readlink }, /* readlink */ |
| 145 | { &vop_abortop_desc, spec_abortop }, /* abortop */ |
| 146 | { &vop_inactive_desc, spec_inactive }, /* inactive */ |
| 147 | { &vop_reclaim_desc, spec_reclaim }, /* reclaim */ |
| 148 | { &vop_lock_desc, spec_lock }, /* lock */ |
| 149 | { &vop_unlock_desc, spec_unlock }, /* unlock */ |
| 150 | { &vop_bmap_desc, spec_bmap }, /* bmap */ |
| 151 | { &vop_strategy_desc, spec_strategy }, /* strategy */ |
| 152 | { &vop_print_desc, spec_print }, /* print */ |
| 153 | { &vop_islocked_desc, spec_islocked }, /* islocked */ |
| 154 | { &vop_pathconf_desc, spec_pathconf }, /* pathconf */ |
| 155 | { &vop_advlock_desc, spec_advlock }, /* advlock */ |
| 156 | { &vop_bwrite_desc, spec_bwrite }, /* bwrite */ |
| 157 | { &vop_getpages_desc, spec_getpages }, /* getpages */ |
| 158 | { &vop_putpages_desc, spec_putpages }, /* putpages */ |
| 159 | { NULL, NULL } |
| 160 | }; |
| 161 | const struct vnodeopv_desc spec_vnodeop_opv_desc = |
| 162 | { &spec_vnodeop_p, spec_vnodeop_entries }; |
| 163 | |
| 164 | static kauth_listener_t rawio_listener; |
| 165 | |
| 166 | /* Returns true if vnode is /dev/mem or /dev/kmem. */ |
| 167 | bool |
| 168 | iskmemvp(struct vnode *vp) |
| 169 | { |
| 170 | return ((vp->v_type == VCHR) && iskmemdev(vp->v_rdev)); |
| 171 | } |
| 172 | |
| 173 | /* |
| 174 | * Returns true if dev is /dev/mem or /dev/kmem. |
| 175 | */ |
| 176 | int |
| 177 | iskmemdev(dev_t dev) |
| 178 | { |
| 179 | /* mem_no is emitted by config(8) to generated devsw.c */ |
| 180 | extern const int mem_no; |
| 181 | |
| 182 | /* minor 14 is /dev/io on i386 with COMPAT_10 */ |
| 183 | return (major(dev) == mem_no && (minor(dev) < 2 || minor(dev) == 14)); |
| 184 | } |
| 185 | |
| 186 | static int |
| 187 | rawio_listener_cb(kauth_cred_t cred, kauth_action_t action, void *cookie, |
| 188 | void *arg0, void *arg1, void *arg2, void *arg3) |
| 189 | { |
| 190 | int result; |
| 191 | |
| 192 | result = KAUTH_RESULT_DEFER; |
| 193 | |
| 194 | if ((action != KAUTH_DEVICE_RAWIO_SPEC) && |
| 195 | (action != KAUTH_DEVICE_RAWIO_PASSTHRU)) |
| 196 | return result; |
| 197 | |
| 198 | /* Access is mandated by permissions. */ |
| 199 | result = KAUTH_RESULT_ALLOW; |
| 200 | |
| 201 | return result; |
| 202 | } |
| 203 | |
| 204 | void |
| 205 | spec_init(void) |
| 206 | { |
| 207 | |
| 208 | rawio_listener = kauth_listen_scope(KAUTH_SCOPE_DEVICE, |
| 209 | rawio_listener_cb, NULL); |
| 210 | } |
| 211 | |
| 212 | /* |
| 213 | * Initialize a vnode that represents a device. |
| 214 | */ |
| 215 | void |
| 216 | spec_node_init(vnode_t *vp, dev_t rdev) |
| 217 | { |
| 218 | specnode_t *sn; |
| 219 | specdev_t *sd; |
| 220 | vnode_t *vp2; |
| 221 | vnode_t **vpp; |
| 222 | |
| 223 | KASSERT(vp->v_type == VBLK || vp->v_type == VCHR); |
| 224 | KASSERT(vp->v_specnode == NULL); |
| 225 | |
| 226 | /* |
| 227 | * Search the hash table for this device. If known, add a |
| 228 | * reference to the device structure. If not known, create |
| 229 | * a new entry to represent the device. In all cases add |
| 230 | * the vnode to the hash table. |
| 231 | */ |
| 232 | sn = kmem_alloc(sizeof(*sn), KM_SLEEP); |
| 233 | if (sn == NULL) { |
| 234 | /* XXX */ |
| 235 | panic("spec_node_init: unable to allocate memory" ); |
| 236 | } |
| 237 | sd = kmem_alloc(sizeof(*sd), KM_SLEEP); |
| 238 | if (sd == NULL) { |
| 239 | /* XXX */ |
| 240 | panic("spec_node_init: unable to allocate memory" ); |
| 241 | } |
| 242 | mutex_enter(&device_lock); |
| 243 | vpp = &specfs_hash[SPECHASH(rdev)]; |
| 244 | for (vp2 = *vpp; vp2 != NULL; vp2 = vp2->v_specnext) { |
| 245 | KASSERT(vp2->v_specnode != NULL); |
| 246 | if (rdev == vp2->v_rdev && vp->v_type == vp2->v_type) { |
| 247 | break; |
| 248 | } |
| 249 | } |
| 250 | if (vp2 == NULL) { |
| 251 | /* No existing record, create a new one. */ |
| 252 | sd->sd_rdev = rdev; |
| 253 | sd->sd_mountpoint = NULL; |
| 254 | sd->sd_lockf = NULL; |
| 255 | sd->sd_refcnt = 1; |
| 256 | sd->sd_opencnt = 0; |
| 257 | sd->sd_bdevvp = NULL; |
| 258 | sn->sn_dev = sd; |
| 259 | sd = NULL; |
| 260 | } else { |
| 261 | /* Use the existing record. */ |
| 262 | sn->sn_dev = vp2->v_specnode->sn_dev; |
| 263 | sn->sn_dev->sd_refcnt++; |
| 264 | } |
| 265 | /* Insert vnode into the hash chain. */ |
| 266 | sn->sn_opencnt = 0; |
| 267 | sn->sn_rdev = rdev; |
| 268 | sn->sn_gone = false; |
| 269 | vp->v_specnode = sn; |
| 270 | vp->v_specnext = *vpp; |
| 271 | *vpp = vp; |
| 272 | mutex_exit(&device_lock); |
| 273 | |
| 274 | /* Free the record we allocated if unused. */ |
| 275 | if (sd != NULL) { |
| 276 | kmem_free(sd, sizeof(*sd)); |
| 277 | } |
| 278 | } |
| 279 | |
| 280 | /* |
| 281 | * Lookup a vnode by device number and return it referenced. |
| 282 | */ |
| 283 | int |
| 284 | spec_node_lookup_by_dev(enum vtype type, dev_t dev, vnode_t **vpp) |
| 285 | { |
| 286 | int error; |
| 287 | vnode_t *vp; |
| 288 | |
| 289 | mutex_enter(&device_lock); |
| 290 | for (vp = specfs_hash[SPECHASH(dev)]; vp; vp = vp->v_specnext) { |
| 291 | if (type == vp->v_type && dev == vp->v_rdev) { |
| 292 | mutex_enter(vp->v_interlock); |
| 293 | /* If clean or being cleaned, then ignore it. */ |
| 294 | if (vdead_check(vp, VDEAD_NOWAIT) == 0) |
| 295 | break; |
| 296 | mutex_exit(vp->v_interlock); |
| 297 | } |
| 298 | } |
| 299 | KASSERT(vp == NULL || mutex_owned(vp->v_interlock)); |
| 300 | if (vp == NULL) { |
| 301 | mutex_exit(&device_lock); |
| 302 | return ENOENT; |
| 303 | } |
| 304 | /* |
| 305 | * If it is an opened block device return the opened vnode. |
| 306 | */ |
| 307 | if (type == VBLK && vp->v_specnode->sn_dev->sd_bdevvp != NULL) { |
| 308 | mutex_exit(vp->v_interlock); |
| 309 | vp = vp->v_specnode->sn_dev->sd_bdevvp; |
| 310 | mutex_enter(vp->v_interlock); |
| 311 | } |
| 312 | mutex_exit(&device_lock); |
| 313 | error = vget(vp, 0, true /* wait */); |
| 314 | if (error != 0) |
| 315 | return error; |
| 316 | *vpp = vp; |
| 317 | |
| 318 | return 0; |
| 319 | } |
| 320 | |
| 321 | /* |
| 322 | * Lookup a vnode by file system mounted on and return it referenced. |
| 323 | */ |
| 324 | int |
| 325 | spec_node_lookup_by_mount(struct mount *mp, vnode_t **vpp) |
| 326 | { |
| 327 | int i, error; |
| 328 | vnode_t *vp, *vq; |
| 329 | |
| 330 | mutex_enter(&device_lock); |
| 331 | for (i = 0, vq = NULL; i < SPECHSZ && vq == NULL; i++) { |
| 332 | for (vp = specfs_hash[i]; vp; vp = vp->v_specnext) { |
| 333 | if (vp->v_type != VBLK) |
| 334 | continue; |
| 335 | vq = vp->v_specnode->sn_dev->sd_bdevvp; |
| 336 | if (vq != NULL && |
| 337 | vq->v_specnode->sn_dev->sd_mountpoint == mp) |
| 338 | break; |
| 339 | vq = NULL; |
| 340 | } |
| 341 | } |
| 342 | if (vq == NULL) { |
| 343 | mutex_exit(&device_lock); |
| 344 | return ENOENT; |
| 345 | } |
| 346 | mutex_enter(vq->v_interlock); |
| 347 | mutex_exit(&device_lock); |
| 348 | error = vget(vq, 0, true /* wait */); |
| 349 | if (error != 0) |
| 350 | return error; |
| 351 | *vpp = vq; |
| 352 | |
| 353 | return 0; |
| 354 | |
| 355 | } |
| 356 | |
| 357 | /* |
| 358 | * Get the file system mounted on this block device. |
| 359 | */ |
| 360 | struct mount * |
| 361 | spec_node_getmountedfs(vnode_t *devvp) |
| 362 | { |
| 363 | struct mount *mp; |
| 364 | |
| 365 | KASSERT(devvp->v_type == VBLK); |
| 366 | mp = devvp->v_specnode->sn_dev->sd_mountpoint; |
| 367 | |
| 368 | return mp; |
| 369 | } |
| 370 | |
| 371 | /* |
| 372 | * Set the file system mounted on this block device. |
| 373 | */ |
| 374 | void |
| 375 | spec_node_setmountedfs(vnode_t *devvp, struct mount *mp) |
| 376 | { |
| 377 | |
| 378 | KASSERT(devvp->v_type == VBLK); |
| 379 | KASSERT(devvp->v_specnode->sn_dev->sd_mountpoint == NULL || mp == NULL); |
| 380 | devvp->v_specnode->sn_dev->sd_mountpoint = mp; |
| 381 | } |
| 382 | |
| 383 | /* |
| 384 | * A vnode representing a special device is going away. Close |
| 385 | * the device if the vnode holds it open. |
| 386 | */ |
| 387 | void |
| 388 | spec_node_revoke(vnode_t *vp) |
| 389 | { |
| 390 | specnode_t *sn; |
| 391 | specdev_t *sd; |
| 392 | |
| 393 | sn = vp->v_specnode; |
| 394 | sd = sn->sn_dev; |
| 395 | |
| 396 | KASSERT(vp->v_type == VBLK || vp->v_type == VCHR); |
| 397 | KASSERT(vp->v_specnode != NULL); |
| 398 | KASSERT(sn->sn_gone == false); |
| 399 | |
| 400 | mutex_enter(&device_lock); |
| 401 | KASSERT(sn->sn_opencnt <= sd->sd_opencnt); |
| 402 | if (sn->sn_opencnt != 0) { |
| 403 | sd->sd_opencnt -= (sn->sn_opencnt - 1); |
| 404 | sn->sn_opencnt = 1; |
| 405 | sn->sn_gone = true; |
| 406 | mutex_exit(&device_lock); |
| 407 | |
| 408 | VOP_CLOSE(vp, FNONBLOCK, NOCRED); |
| 409 | |
| 410 | mutex_enter(&device_lock); |
| 411 | KASSERT(sn->sn_opencnt == 0); |
| 412 | } |
| 413 | mutex_exit(&device_lock); |
| 414 | } |
| 415 | |
| 416 | /* |
| 417 | * A vnode representing a special device is being recycled. |
| 418 | * Destroy the specfs component. |
| 419 | */ |
| 420 | void |
| 421 | spec_node_destroy(vnode_t *vp) |
| 422 | { |
| 423 | specnode_t *sn; |
| 424 | specdev_t *sd; |
| 425 | vnode_t **vpp, *vp2; |
| 426 | int refcnt; |
| 427 | |
| 428 | sn = vp->v_specnode; |
| 429 | sd = sn->sn_dev; |
| 430 | |
| 431 | KASSERT(vp->v_type == VBLK || vp->v_type == VCHR); |
| 432 | KASSERT(vp->v_specnode != NULL); |
| 433 | KASSERT(sn->sn_opencnt == 0); |
| 434 | |
| 435 | mutex_enter(&device_lock); |
| 436 | /* Remove from the hash and destroy the node. */ |
| 437 | vpp = &specfs_hash[SPECHASH(vp->v_rdev)]; |
| 438 | for (vp2 = *vpp;; vp2 = vp2->v_specnext) { |
| 439 | if (vp2 == NULL) { |
| 440 | panic("spec_node_destroy: corrupt hash" ); |
| 441 | } |
| 442 | if (vp2 == vp) { |
| 443 | KASSERT(vp == *vpp); |
| 444 | *vpp = vp->v_specnext; |
| 445 | break; |
| 446 | } |
| 447 | if (vp2->v_specnext == vp) { |
| 448 | vp2->v_specnext = vp->v_specnext; |
| 449 | break; |
| 450 | } |
| 451 | } |
| 452 | sn = vp->v_specnode; |
| 453 | vp->v_specnode = NULL; |
| 454 | refcnt = sd->sd_refcnt--; |
| 455 | KASSERT(refcnt > 0); |
| 456 | mutex_exit(&device_lock); |
| 457 | |
| 458 | /* If the device is no longer in use, destroy our record. */ |
| 459 | if (refcnt == 1) { |
| 460 | KASSERT(sd->sd_opencnt == 0); |
| 461 | KASSERT(sd->sd_bdevvp == NULL); |
| 462 | kmem_free(sd, sizeof(*sd)); |
| 463 | } |
| 464 | kmem_free(sn, sizeof(*sn)); |
| 465 | } |
| 466 | |
| 467 | /* |
| 468 | * Trivial lookup routine that always fails. |
| 469 | */ |
| 470 | int |
| 471 | spec_lookup(void *v) |
| 472 | { |
| 473 | struct vop_lookup_v2_args /* { |
| 474 | struct vnode *a_dvp; |
| 475 | struct vnode **a_vpp; |
| 476 | struct componentname *a_cnp; |
| 477 | } */ *ap = v; |
| 478 | |
| 479 | *ap->a_vpp = NULL; |
| 480 | return (ENOTDIR); |
| 481 | } |
| 482 | |
| 483 | typedef int (*spec_ioctl_t)(dev_t, u_long, void *, int, struct lwp *); |
| 484 | |
| 485 | /* |
| 486 | * Open a special file. |
| 487 | */ |
| 488 | /* ARGSUSED */ |
| 489 | int |
| 490 | spec_open(void *v) |
| 491 | { |
| 492 | struct vop_open_args /* { |
| 493 | struct vnode *a_vp; |
| 494 | int a_mode; |
| 495 | kauth_cred_t a_cred; |
| 496 | } */ *ap = v; |
| 497 | struct lwp *l; |
| 498 | struct vnode *vp; |
| 499 | dev_t dev; |
| 500 | int error; |
| 501 | enum kauth_device_req req; |
| 502 | specnode_t *sn; |
| 503 | specdev_t *sd; |
| 504 | spec_ioctl_t ioctl; |
| 505 | u_int gen; |
| 506 | const char *name; |
| 507 | struct partinfo pi; |
| 508 | |
| 509 | l = curlwp; |
| 510 | vp = ap->a_vp; |
| 511 | dev = vp->v_rdev; |
| 512 | sn = vp->v_specnode; |
| 513 | sd = sn->sn_dev; |
| 514 | name = NULL; |
| 515 | gen = 0; |
| 516 | |
| 517 | /* |
| 518 | * Don't allow open if fs is mounted -nodev. |
| 519 | */ |
| 520 | if (vp->v_mount && (vp->v_mount->mnt_flag & MNT_NODEV)) |
| 521 | return (ENXIO); |
| 522 | |
| 523 | switch (ap->a_mode & (FREAD | FWRITE)) { |
| 524 | case FREAD | FWRITE: |
| 525 | req = KAUTH_REQ_DEVICE_RAWIO_SPEC_RW; |
| 526 | break; |
| 527 | case FWRITE: |
| 528 | req = KAUTH_REQ_DEVICE_RAWIO_SPEC_WRITE; |
| 529 | break; |
| 530 | default: |
| 531 | req = KAUTH_REQ_DEVICE_RAWIO_SPEC_READ; |
| 532 | break; |
| 533 | } |
| 534 | |
| 535 | switch (vp->v_type) { |
| 536 | case VCHR: |
| 537 | error = kauth_authorize_device_spec(ap->a_cred, req, vp); |
| 538 | if (error != 0) |
| 539 | return (error); |
| 540 | |
| 541 | /* |
| 542 | * Character devices can accept opens from multiple |
| 543 | * vnodes. |
| 544 | */ |
| 545 | mutex_enter(&device_lock); |
| 546 | if (sn->sn_gone) { |
| 547 | mutex_exit(&device_lock); |
| 548 | return (EBADF); |
| 549 | } |
| 550 | sd->sd_opencnt++; |
| 551 | sn->sn_opencnt++; |
| 552 | mutex_exit(&device_lock); |
| 553 | if (cdev_type(dev) == D_TTY) |
| 554 | vp->v_vflag |= VV_ISTTY; |
| 555 | VOP_UNLOCK(vp); |
| 556 | do { |
| 557 | const struct cdevsw *cdev; |
| 558 | |
| 559 | gen = module_gen; |
| 560 | error = cdev_open(dev, ap->a_mode, S_IFCHR, l); |
| 561 | if (error != ENXIO) |
| 562 | break; |
| 563 | |
| 564 | /* Check if we already have a valid driver */ |
| 565 | mutex_enter(&device_lock); |
| 566 | cdev = cdevsw_lookup(dev); |
| 567 | mutex_exit(&device_lock); |
| 568 | if (cdev != NULL) |
| 569 | break; |
| 570 | |
| 571 | /* Get device name from devsw_conv array */ |
| 572 | if ((name = cdevsw_getname(major(dev))) == NULL) |
| 573 | break; |
| 574 | |
| 575 | /* Try to autoload device module */ |
| 576 | (void) module_autoload(name, MODULE_CLASS_DRIVER); |
| 577 | } while (gen != module_gen); |
| 578 | |
| 579 | vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); |
| 580 | break; |
| 581 | |
| 582 | case VBLK: |
| 583 | error = kauth_authorize_device_spec(ap->a_cred, req, vp); |
| 584 | if (error != 0) |
| 585 | return (error); |
| 586 | |
| 587 | /* |
| 588 | * For block devices, permit only one open. The buffer |
| 589 | * cache cannot remain self-consistent with multiple |
| 590 | * vnodes holding a block device open. |
| 591 | */ |
| 592 | mutex_enter(&device_lock); |
| 593 | if (sn->sn_gone) { |
| 594 | mutex_exit(&device_lock); |
| 595 | return (EBADF); |
| 596 | } |
| 597 | if (sd->sd_opencnt != 0) { |
| 598 | mutex_exit(&device_lock); |
| 599 | return EBUSY; |
| 600 | } |
| 601 | sn->sn_opencnt = 1; |
| 602 | sd->sd_opencnt = 1; |
| 603 | sd->sd_bdevvp = vp; |
| 604 | mutex_exit(&device_lock); |
| 605 | do { |
| 606 | const struct bdevsw *bdev; |
| 607 | |
| 608 | gen = module_gen; |
| 609 | error = bdev_open(dev, ap->a_mode, S_IFBLK, l); |
| 610 | if (error != ENXIO) |
| 611 | break; |
| 612 | |
| 613 | /* Check if we already have a valid driver */ |
| 614 | mutex_enter(&device_lock); |
| 615 | bdev = bdevsw_lookup(dev); |
| 616 | mutex_exit(&device_lock); |
| 617 | if (bdev != NULL) |
| 618 | break; |
| 619 | |
| 620 | /* Get device name from devsw_conv array */ |
| 621 | if ((name = bdevsw_getname(major(dev))) == NULL) |
| 622 | break; |
| 623 | |
| 624 | VOP_UNLOCK(vp); |
| 625 | |
| 626 | /* Try to autoload device module */ |
| 627 | (void) module_autoload(name, MODULE_CLASS_DRIVER); |
| 628 | |
| 629 | vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); |
| 630 | } while (gen != module_gen); |
| 631 | |
| 632 | break; |
| 633 | |
| 634 | case VNON: |
| 635 | case VLNK: |
| 636 | case VDIR: |
| 637 | case VREG: |
| 638 | case VBAD: |
| 639 | case VFIFO: |
| 640 | case VSOCK: |
| 641 | default: |
| 642 | return 0; |
| 643 | } |
| 644 | |
| 645 | mutex_enter(&device_lock); |
| 646 | if (sn->sn_gone) { |
| 647 | if (error == 0) |
| 648 | error = EBADF; |
| 649 | } else if (error != 0) { |
| 650 | sd->sd_opencnt--; |
| 651 | sn->sn_opencnt--; |
| 652 | if (vp->v_type == VBLK) |
| 653 | sd->sd_bdevvp = NULL; |
| 654 | |
| 655 | } |
| 656 | mutex_exit(&device_lock); |
| 657 | |
| 658 | if (cdev_type(dev) != D_DISK || error != 0) |
| 659 | return error; |
| 660 | |
| 661 | |
| 662 | ioctl = vp->v_type == VCHR ? cdev_ioctl : bdev_ioctl; |
| 663 | error = (*ioctl)(vp->v_rdev, DIOCGPARTINFO, &pi, FREAD, curlwp); |
| 664 | if (error == 0) |
| 665 | uvm_vnp_setsize(vp, (voff_t)pi.pi_secsize * pi.pi_size); |
| 666 | |
| 667 | return 0; |
| 668 | } |
| 669 | |
| 670 | /* |
| 671 | * Vnode op for read |
| 672 | */ |
| 673 | /* ARGSUSED */ |
| 674 | int |
| 675 | spec_read(void *v) |
| 676 | { |
| 677 | struct vop_read_args /* { |
| 678 | struct vnode *a_vp; |
| 679 | struct uio *a_uio; |
| 680 | int a_ioflag; |
| 681 | kauth_cred_t a_cred; |
| 682 | } */ *ap = v; |
| 683 | struct vnode *vp = ap->a_vp; |
| 684 | struct uio *uio = ap->a_uio; |
| 685 | struct lwp *l = curlwp; |
| 686 | struct buf *bp; |
| 687 | daddr_t bn; |
| 688 | int bsize, bscale; |
| 689 | struct partinfo pi; |
| 690 | int n, on; |
| 691 | int error = 0; |
| 692 | |
| 693 | KASSERT(uio->uio_rw == UIO_READ); |
| 694 | KASSERTMSG(VMSPACE_IS_KERNEL_P(uio->uio_vmspace) || |
| 695 | uio->uio_vmspace == curproc->p_vmspace, |
| 696 | "vmspace belongs to neither kernel nor curproc" ); |
| 697 | |
| 698 | if (uio->uio_resid == 0) |
| 699 | return (0); |
| 700 | |
| 701 | switch (vp->v_type) { |
| 702 | |
| 703 | case VCHR: |
| 704 | VOP_UNLOCK(vp); |
| 705 | error = cdev_read(vp->v_rdev, uio, ap->a_ioflag); |
| 706 | vn_lock(vp, LK_SHARED | LK_RETRY); |
| 707 | return (error); |
| 708 | |
| 709 | case VBLK: |
| 710 | KASSERT(vp == vp->v_specnode->sn_dev->sd_bdevvp); |
| 711 | if (uio->uio_offset < 0) |
| 712 | return (EINVAL); |
| 713 | |
| 714 | if (bdev_ioctl(vp->v_rdev, DIOCGPARTINFO, &pi, FREAD, l) == 0) |
| 715 | bsize = pi.pi_bsize; |
| 716 | else |
| 717 | bsize = BLKDEV_IOSIZE; |
| 718 | |
| 719 | bscale = bsize >> DEV_BSHIFT; |
| 720 | do { |
| 721 | bn = (uio->uio_offset >> DEV_BSHIFT) &~ (bscale - 1); |
| 722 | on = uio->uio_offset % bsize; |
| 723 | n = min((unsigned)(bsize - on), uio->uio_resid); |
| 724 | error = bread(vp, bn, bsize, 0, &bp); |
| 725 | if (error) { |
| 726 | return (error); |
| 727 | } |
| 728 | n = min(n, bsize - bp->b_resid); |
| 729 | error = uiomove((char *)bp->b_data + on, n, uio); |
| 730 | brelse(bp, 0); |
| 731 | } while (error == 0 && uio->uio_resid > 0 && n != 0); |
| 732 | return (error); |
| 733 | |
| 734 | default: |
| 735 | panic("spec_read type" ); |
| 736 | } |
| 737 | /* NOTREACHED */ |
| 738 | } |
| 739 | |
| 740 | /* |
| 741 | * Vnode op for write |
| 742 | */ |
| 743 | /* ARGSUSED */ |
| 744 | int |
| 745 | spec_write(void *v) |
| 746 | { |
| 747 | struct vop_write_args /* { |
| 748 | struct vnode *a_vp; |
| 749 | struct uio *a_uio; |
| 750 | int a_ioflag; |
| 751 | kauth_cred_t a_cred; |
| 752 | } */ *ap = v; |
| 753 | struct vnode *vp = ap->a_vp; |
| 754 | struct uio *uio = ap->a_uio; |
| 755 | struct lwp *l = curlwp; |
| 756 | struct buf *bp; |
| 757 | daddr_t bn; |
| 758 | int bsize, bscale; |
| 759 | struct partinfo pi; |
| 760 | int n, on; |
| 761 | int error = 0; |
| 762 | |
| 763 | KASSERT(uio->uio_rw == UIO_WRITE); |
| 764 | KASSERTMSG(VMSPACE_IS_KERNEL_P(uio->uio_vmspace) || |
| 765 | uio->uio_vmspace == curproc->p_vmspace, |
| 766 | "vmspace belongs to neither kernel nor curproc" ); |
| 767 | |
| 768 | switch (vp->v_type) { |
| 769 | |
| 770 | case VCHR: |
| 771 | VOP_UNLOCK(vp); |
| 772 | error = cdev_write(vp->v_rdev, uio, ap->a_ioflag); |
| 773 | vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); |
| 774 | return (error); |
| 775 | |
| 776 | case VBLK: |
| 777 | KASSERT(vp == vp->v_specnode->sn_dev->sd_bdevvp); |
| 778 | if (uio->uio_resid == 0) |
| 779 | return (0); |
| 780 | if (uio->uio_offset < 0) |
| 781 | return (EINVAL); |
| 782 | |
| 783 | if (bdev_ioctl(vp->v_rdev, DIOCGPARTINFO, &pi, FREAD, l) == 0) |
| 784 | bsize = pi.pi_bsize; |
| 785 | else |
| 786 | bsize = BLKDEV_IOSIZE; |
| 787 | |
| 788 | bscale = bsize >> DEV_BSHIFT; |
| 789 | do { |
| 790 | bn = (uio->uio_offset >> DEV_BSHIFT) &~ (bscale - 1); |
| 791 | on = uio->uio_offset % bsize; |
| 792 | n = min((unsigned)(bsize - on), uio->uio_resid); |
| 793 | if (n == bsize) |
| 794 | bp = getblk(vp, bn, bsize, 0, 0); |
| 795 | else |
| 796 | error = bread(vp, bn, bsize, B_MODIFY, &bp); |
| 797 | if (error) { |
| 798 | return (error); |
| 799 | } |
| 800 | n = min(n, bsize - bp->b_resid); |
| 801 | error = uiomove((char *)bp->b_data + on, n, uio); |
| 802 | if (error) |
| 803 | brelse(bp, 0); |
| 804 | else { |
| 805 | if (n + on == bsize) |
| 806 | bawrite(bp); |
| 807 | else |
| 808 | bdwrite(bp); |
| 809 | error = bp->b_error; |
| 810 | } |
| 811 | } while (error == 0 && uio->uio_resid > 0 && n != 0); |
| 812 | return (error); |
| 813 | |
| 814 | default: |
| 815 | panic("spec_write type" ); |
| 816 | } |
| 817 | /* NOTREACHED */ |
| 818 | } |
| 819 | |
| 820 | /* |
| 821 | * fdiscard, which on disk devices becomes TRIM. |
| 822 | */ |
| 823 | int |
| 824 | spec_fdiscard(void *v) |
| 825 | { |
| 826 | struct vop_fdiscard_args /* { |
| 827 | struct vnode *a_vp; |
| 828 | off_t a_pos; |
| 829 | off_t a_len; |
| 830 | } */ *ap = v; |
| 831 | struct vnode *vp; |
| 832 | dev_t dev; |
| 833 | |
| 834 | vp = ap->a_vp; |
| 835 | dev = NODEV; |
| 836 | |
| 837 | mutex_enter(vp->v_interlock); |
| 838 | if (vdead_check(vp, VDEAD_NOWAIT) == 0 && vp->v_specnode != NULL) { |
| 839 | dev = vp->v_rdev; |
| 840 | } |
| 841 | mutex_exit(vp->v_interlock); |
| 842 | |
| 843 | if (dev == NODEV) { |
| 844 | return ENXIO; |
| 845 | } |
| 846 | |
| 847 | switch (vp->v_type) { |
| 848 | case VCHR: |
| 849 | // this is not stored for character devices |
| 850 | //KASSERT(vp == vp->v_specnode->sn_dev->sd_cdevvp); |
| 851 | return cdev_discard(dev, ap->a_pos, ap->a_len); |
| 852 | case VBLK: |
| 853 | KASSERT(vp == vp->v_specnode->sn_dev->sd_bdevvp); |
| 854 | return bdev_discard(dev, ap->a_pos, ap->a_len); |
| 855 | default: |
| 856 | panic("spec_fdiscard: not a device\n" ); |
| 857 | } |
| 858 | } |
| 859 | |
| 860 | /* |
| 861 | * Device ioctl operation. |
| 862 | */ |
| 863 | /* ARGSUSED */ |
| 864 | int |
| 865 | spec_ioctl(void *v) |
| 866 | { |
| 867 | struct vop_ioctl_args /* { |
| 868 | struct vnode *a_vp; |
| 869 | u_long a_command; |
| 870 | void *a_data; |
| 871 | int a_fflag; |
| 872 | kauth_cred_t a_cred; |
| 873 | } */ *ap = v; |
| 874 | struct vnode *vp; |
| 875 | dev_t dev; |
| 876 | |
| 877 | /* |
| 878 | * Extract all the info we need from the vnode, taking care to |
| 879 | * avoid a race with VOP_REVOKE(). |
| 880 | */ |
| 881 | |
| 882 | vp = ap->a_vp; |
| 883 | dev = NODEV; |
| 884 | mutex_enter(vp->v_interlock); |
| 885 | if (vdead_check(vp, VDEAD_NOWAIT) == 0 && vp->v_specnode) { |
| 886 | dev = vp->v_rdev; |
| 887 | } |
| 888 | mutex_exit(vp->v_interlock); |
| 889 | if (dev == NODEV) { |
| 890 | return ENXIO; |
| 891 | } |
| 892 | |
| 893 | switch (vp->v_type) { |
| 894 | |
| 895 | case VCHR: |
| 896 | return cdev_ioctl(dev, ap->a_command, ap->a_data, |
| 897 | ap->a_fflag, curlwp); |
| 898 | |
| 899 | case VBLK: |
| 900 | KASSERT(vp == vp->v_specnode->sn_dev->sd_bdevvp); |
| 901 | return bdev_ioctl(dev, ap->a_command, ap->a_data, |
| 902 | ap->a_fflag, curlwp); |
| 903 | |
| 904 | default: |
| 905 | panic("spec_ioctl" ); |
| 906 | /* NOTREACHED */ |
| 907 | } |
| 908 | } |
| 909 | |
| 910 | /* ARGSUSED */ |
| 911 | int |
| 912 | spec_poll(void *v) |
| 913 | { |
| 914 | struct vop_poll_args /* { |
| 915 | struct vnode *a_vp; |
| 916 | int a_events; |
| 917 | } */ *ap = v; |
| 918 | struct vnode *vp; |
| 919 | dev_t dev; |
| 920 | |
| 921 | /* |
| 922 | * Extract all the info we need from the vnode, taking care to |
| 923 | * avoid a race with VOP_REVOKE(). |
| 924 | */ |
| 925 | |
| 926 | vp = ap->a_vp; |
| 927 | dev = NODEV; |
| 928 | mutex_enter(vp->v_interlock); |
| 929 | if (vdead_check(vp, VDEAD_NOWAIT) == 0 && vp->v_specnode) { |
| 930 | dev = vp->v_rdev; |
| 931 | } |
| 932 | mutex_exit(vp->v_interlock); |
| 933 | if (dev == NODEV) { |
| 934 | return POLLERR; |
| 935 | } |
| 936 | |
| 937 | switch (vp->v_type) { |
| 938 | |
| 939 | case VCHR: |
| 940 | return cdev_poll(dev, ap->a_events, curlwp); |
| 941 | |
| 942 | default: |
| 943 | return (genfs_poll(v)); |
| 944 | } |
| 945 | } |
| 946 | |
| 947 | /* ARGSUSED */ |
| 948 | int |
| 949 | spec_kqfilter(void *v) |
| 950 | { |
| 951 | struct vop_kqfilter_args /* { |
| 952 | struct vnode *a_vp; |
| 953 | struct proc *a_kn; |
| 954 | } */ *ap = v; |
| 955 | dev_t dev; |
| 956 | |
| 957 | switch (ap->a_vp->v_type) { |
| 958 | |
| 959 | case VCHR: |
| 960 | dev = ap->a_vp->v_rdev; |
| 961 | return cdev_kqfilter(dev, ap->a_kn); |
| 962 | default: |
| 963 | /* |
| 964 | * Block devices don't support kqfilter, and refuse it |
| 965 | * for any other files (like those vflush()ed) too. |
| 966 | */ |
| 967 | return (EOPNOTSUPP); |
| 968 | } |
| 969 | } |
| 970 | |
| 971 | /* |
| 972 | * Allow mapping of only D_DISK. This is called only for VBLK. |
| 973 | */ |
| 974 | int |
| 975 | spec_mmap(void *v) |
| 976 | { |
| 977 | struct vop_mmap_args /* { |
| 978 | struct vnode *a_vp; |
| 979 | vm_prot_t a_prot; |
| 980 | kauth_cred_t a_cred; |
| 981 | } */ *ap = v; |
| 982 | struct vnode *vp = ap->a_vp; |
| 983 | |
| 984 | KASSERT(vp->v_type == VBLK); |
| 985 | if (bdev_type(vp->v_rdev) != D_DISK) |
| 986 | return EINVAL; |
| 987 | |
| 988 | return 0; |
| 989 | } |
| 990 | |
| 991 | /* |
| 992 | * Synch buffers associated with a block device |
| 993 | */ |
| 994 | /* ARGSUSED */ |
| 995 | int |
| 996 | spec_fsync(void *v) |
| 997 | { |
| 998 | struct vop_fsync_args /* { |
| 999 | struct vnode *a_vp; |
| 1000 | kauth_cred_t a_cred; |
| 1001 | int a_flags; |
| 1002 | off_t offlo; |
| 1003 | off_t offhi; |
| 1004 | } */ *ap = v; |
| 1005 | struct vnode *vp = ap->a_vp; |
| 1006 | struct mount *mp; |
| 1007 | int error; |
| 1008 | |
| 1009 | if (vp->v_type == VBLK) { |
| 1010 | if ((mp = spec_node_getmountedfs(vp)) != NULL) { |
| 1011 | error = VFS_FSYNC(mp, vp, ap->a_flags); |
| 1012 | if (error != EOPNOTSUPP) |
| 1013 | return error; |
| 1014 | } |
| 1015 | return vflushbuf(vp, ap->a_flags); |
| 1016 | } |
| 1017 | return (0); |
| 1018 | } |
| 1019 | |
| 1020 | /* |
| 1021 | * Just call the device strategy routine |
| 1022 | */ |
| 1023 | int |
| 1024 | spec_strategy(void *v) |
| 1025 | { |
| 1026 | struct vop_strategy_args /* { |
| 1027 | struct vnode *a_vp; |
| 1028 | struct buf *a_bp; |
| 1029 | } */ *ap = v; |
| 1030 | struct vnode *vp = ap->a_vp; |
| 1031 | struct buf *bp = ap->a_bp; |
| 1032 | dev_t dev; |
| 1033 | int error; |
| 1034 | |
| 1035 | dev = NODEV; |
| 1036 | |
| 1037 | /* |
| 1038 | * Extract all the info we need from the vnode, taking care to |
| 1039 | * avoid a race with VOP_REVOKE(). |
| 1040 | */ |
| 1041 | |
| 1042 | mutex_enter(vp->v_interlock); |
| 1043 | if (vdead_check(vp, VDEAD_NOWAIT) == 0 && vp->v_specnode != NULL) { |
| 1044 | KASSERT(vp == vp->v_specnode->sn_dev->sd_bdevvp); |
| 1045 | dev = vp->v_rdev; |
| 1046 | } |
| 1047 | mutex_exit(vp->v_interlock); |
| 1048 | |
| 1049 | if (dev == NODEV) { |
| 1050 | error = ENXIO; |
| 1051 | goto out; |
| 1052 | } |
| 1053 | bp->b_dev = dev; |
| 1054 | |
| 1055 | if (!(bp->b_flags & B_READ)) { |
| 1056 | error = fscow_run(bp, false); |
| 1057 | if (error) |
| 1058 | goto out; |
| 1059 | } |
| 1060 | bdev_strategy(bp); |
| 1061 | |
| 1062 | return 0; |
| 1063 | |
| 1064 | out: |
| 1065 | bp->b_error = error; |
| 1066 | bp->b_resid = bp->b_bcount; |
| 1067 | biodone(bp); |
| 1068 | |
| 1069 | return error; |
| 1070 | } |
| 1071 | |
| 1072 | int |
| 1073 | spec_inactive(void *v) |
| 1074 | { |
| 1075 | struct vop_inactive_args /* { |
| 1076 | struct vnode *a_vp; |
| 1077 | struct bool *a_recycle; |
| 1078 | } */ *ap = v; |
| 1079 | struct vnode *vp = ap->a_vp; |
| 1080 | |
| 1081 | KASSERT(vp->v_mount == dead_rootmount); |
| 1082 | *ap->a_recycle = true; |
| 1083 | VOP_UNLOCK(vp); |
| 1084 | return 0; |
| 1085 | } |
| 1086 | |
| 1087 | int |
| 1088 | spec_reclaim(void *v) |
| 1089 | { |
| 1090 | struct vop_reclaim_args /* { |
| 1091 | struct vnode *a_vp; |
| 1092 | } */ *ap = v; |
| 1093 | struct vnode *vp __diagused = ap->a_vp; |
| 1094 | |
| 1095 | KASSERT(vp->v_mount == dead_rootmount); |
| 1096 | return 0; |
| 1097 | } |
| 1098 | |
| 1099 | /* |
| 1100 | * This is a noop, simply returning what one has been given. |
| 1101 | */ |
| 1102 | int |
| 1103 | spec_bmap(void *v) |
| 1104 | { |
| 1105 | struct vop_bmap_args /* { |
| 1106 | struct vnode *a_vp; |
| 1107 | daddr_t a_bn; |
| 1108 | struct vnode **a_vpp; |
| 1109 | daddr_t *a_bnp; |
| 1110 | int *a_runp; |
| 1111 | } */ *ap = v; |
| 1112 | |
| 1113 | if (ap->a_vpp != NULL) |
| 1114 | *ap->a_vpp = ap->a_vp; |
| 1115 | if (ap->a_bnp != NULL) |
| 1116 | *ap->a_bnp = ap->a_bn; |
| 1117 | if (ap->a_runp != NULL) |
| 1118 | *ap->a_runp = (MAXBSIZE >> DEV_BSHIFT) - 1; |
| 1119 | return (0); |
| 1120 | } |
| 1121 | |
| 1122 | /* |
| 1123 | * Device close routine |
| 1124 | */ |
| 1125 | /* ARGSUSED */ |
| 1126 | int |
| 1127 | spec_close(void *v) |
| 1128 | { |
| 1129 | struct vop_close_args /* { |
| 1130 | struct vnode *a_vp; |
| 1131 | int a_fflag; |
| 1132 | kauth_cred_t a_cred; |
| 1133 | } */ *ap = v; |
| 1134 | struct vnode *vp = ap->a_vp; |
| 1135 | struct session *sess; |
| 1136 | dev_t dev = vp->v_rdev; |
| 1137 | int flags = ap->a_fflag; |
| 1138 | int mode, error, count; |
| 1139 | specnode_t *sn; |
| 1140 | specdev_t *sd; |
| 1141 | |
| 1142 | mutex_enter(vp->v_interlock); |
| 1143 | sn = vp->v_specnode; |
| 1144 | sd = sn->sn_dev; |
| 1145 | /* |
| 1146 | * If we're going away soon, make this non-blocking. |
| 1147 | * Also ensures that we won't wedge in vn_lock below. |
| 1148 | */ |
| 1149 | if (vdead_check(vp, VDEAD_NOWAIT) != 0) |
| 1150 | flags |= FNONBLOCK; |
| 1151 | mutex_exit(vp->v_interlock); |
| 1152 | |
| 1153 | switch (vp->v_type) { |
| 1154 | |
| 1155 | case VCHR: |
| 1156 | /* |
| 1157 | * Hack: a tty device that is a controlling terminal |
| 1158 | * has a reference from the session structure. We |
| 1159 | * cannot easily tell that a character device is a |
| 1160 | * controlling terminal, unless it is the closing |
| 1161 | * process' controlling terminal. In that case, if the |
| 1162 | * open count is 1 release the reference from the |
| 1163 | * session. Also, remove the link from the tty back to |
| 1164 | * the session and pgrp. |
| 1165 | * |
| 1166 | * XXX V. fishy. |
| 1167 | */ |
| 1168 | mutex_enter(proc_lock); |
| 1169 | sess = curlwp->l_proc->p_session; |
| 1170 | if (sn->sn_opencnt == 1 && vp == sess->s_ttyvp) { |
| 1171 | mutex_spin_enter(&tty_lock); |
| 1172 | sess->s_ttyvp = NULL; |
| 1173 | if (sess->s_ttyp->t_session != NULL) { |
| 1174 | sess->s_ttyp->t_pgrp = NULL; |
| 1175 | sess->s_ttyp->t_session = NULL; |
| 1176 | mutex_spin_exit(&tty_lock); |
| 1177 | /* Releases proc_lock. */ |
| 1178 | proc_sessrele(sess); |
| 1179 | } else { |
| 1180 | mutex_spin_exit(&tty_lock); |
| 1181 | if (sess->s_ttyp->t_pgrp != NULL) |
| 1182 | panic("spec_close: spurious pgrp ref" ); |
| 1183 | mutex_exit(proc_lock); |
| 1184 | } |
| 1185 | vrele(vp); |
| 1186 | } else |
| 1187 | mutex_exit(proc_lock); |
| 1188 | |
| 1189 | /* |
| 1190 | * If the vnode is locked, then we are in the midst |
| 1191 | * of forcably closing the device, otherwise we only |
| 1192 | * close on last reference. |
| 1193 | */ |
| 1194 | mode = S_IFCHR; |
| 1195 | break; |
| 1196 | |
| 1197 | case VBLK: |
| 1198 | KASSERT(vp == vp->v_specnode->sn_dev->sd_bdevvp); |
| 1199 | /* |
| 1200 | * On last close of a block device (that isn't mounted) |
| 1201 | * we must invalidate any in core blocks, so that |
| 1202 | * we can, for instance, change floppy disks. |
| 1203 | */ |
| 1204 | error = vinvalbuf(vp, V_SAVE, ap->a_cred, curlwp, 0, 0); |
| 1205 | if (error) |
| 1206 | return (error); |
| 1207 | /* |
| 1208 | * We do not want to really close the device if it |
| 1209 | * is still in use unless we are trying to close it |
| 1210 | * forcibly. Since every use (buffer, vnode, swap, cmap) |
| 1211 | * holds a reference to the vnode, and because we mark |
| 1212 | * any other vnodes that alias this device, when the |
| 1213 | * sum of the reference counts on all the aliased |
| 1214 | * vnodes descends to one, we are on last close. |
| 1215 | */ |
| 1216 | mode = S_IFBLK; |
| 1217 | break; |
| 1218 | |
| 1219 | default: |
| 1220 | panic("spec_close: not special" ); |
| 1221 | } |
| 1222 | |
| 1223 | mutex_enter(&device_lock); |
| 1224 | sn->sn_opencnt--; |
| 1225 | count = --sd->sd_opencnt; |
| 1226 | if (vp->v_type == VBLK) |
| 1227 | sd->sd_bdevvp = NULL; |
| 1228 | mutex_exit(&device_lock); |
| 1229 | |
| 1230 | if (count != 0) |
| 1231 | return 0; |
| 1232 | |
| 1233 | /* |
| 1234 | * If we're able to block, release the vnode lock & reacquire. We |
| 1235 | * might end up sleeping for someone else who wants our queues. They |
| 1236 | * won't get them if we hold the vnode locked. |
| 1237 | */ |
| 1238 | if (!(flags & FNONBLOCK)) |
| 1239 | VOP_UNLOCK(vp); |
| 1240 | |
| 1241 | if (vp->v_type == VBLK) |
| 1242 | error = bdev_close(dev, flags, mode, curlwp); |
| 1243 | else |
| 1244 | error = cdev_close(dev, flags, mode, curlwp); |
| 1245 | |
| 1246 | if (!(flags & FNONBLOCK)) |
| 1247 | vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); |
| 1248 | |
| 1249 | return (error); |
| 1250 | } |
| 1251 | |
| 1252 | /* |
| 1253 | * Print out the contents of a special device vnode. |
| 1254 | */ |
| 1255 | int |
| 1256 | spec_print(void *v) |
| 1257 | { |
| 1258 | struct vop_print_args /* { |
| 1259 | struct vnode *a_vp; |
| 1260 | } */ *ap = v; |
| 1261 | |
| 1262 | printf("dev %llu, %llu\n" , (unsigned long long)major(ap->a_vp->v_rdev), |
| 1263 | (unsigned long long)minor(ap->a_vp->v_rdev)); |
| 1264 | return 0; |
| 1265 | } |
| 1266 | |
| 1267 | /* |
| 1268 | * Return POSIX pathconf information applicable to special devices. |
| 1269 | */ |
| 1270 | int |
| 1271 | spec_pathconf(void *v) |
| 1272 | { |
| 1273 | struct vop_pathconf_args /* { |
| 1274 | struct vnode *a_vp; |
| 1275 | int a_name; |
| 1276 | register_t *a_retval; |
| 1277 | } */ *ap = v; |
| 1278 | |
| 1279 | switch (ap->a_name) { |
| 1280 | case _PC_LINK_MAX: |
| 1281 | *ap->a_retval = LINK_MAX; |
| 1282 | return (0); |
| 1283 | case _PC_MAX_CANON: |
| 1284 | *ap->a_retval = MAX_CANON; |
| 1285 | return (0); |
| 1286 | case _PC_MAX_INPUT: |
| 1287 | *ap->a_retval = MAX_INPUT; |
| 1288 | return (0); |
| 1289 | case _PC_PIPE_BUF: |
| 1290 | *ap->a_retval = PIPE_BUF; |
| 1291 | return (0); |
| 1292 | case _PC_CHOWN_RESTRICTED: |
| 1293 | *ap->a_retval = 1; |
| 1294 | return (0); |
| 1295 | case _PC_VDISABLE: |
| 1296 | *ap->a_retval = _POSIX_VDISABLE; |
| 1297 | return (0); |
| 1298 | case _PC_SYNC_IO: |
| 1299 | *ap->a_retval = 1; |
| 1300 | return (0); |
| 1301 | default: |
| 1302 | return (EINVAL); |
| 1303 | } |
| 1304 | /* NOTREACHED */ |
| 1305 | } |
| 1306 | |
| 1307 | /* |
| 1308 | * Advisory record locking support. |
| 1309 | */ |
| 1310 | int |
| 1311 | spec_advlock(void *v) |
| 1312 | { |
| 1313 | struct vop_advlock_args /* { |
| 1314 | struct vnode *a_vp; |
| 1315 | void *a_id; |
| 1316 | int a_op; |
| 1317 | struct flock *a_fl; |
| 1318 | int a_flags; |
| 1319 | } */ *ap = v; |
| 1320 | struct vnode *vp = ap->a_vp; |
| 1321 | |
| 1322 | return lf_advlock(ap, &vp->v_speclockf, (off_t)0); |
| 1323 | } |
| 1324 | |