/* $NetBSD: spec_vnops.c,v 1.173.2.1 2017/07/01 08:54:08 snj Exp $ */ /*- * Copyright (c) 2008 The NetBSD Foundation, Inc. * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. */ /* * Copyright (c) 1989, 1993 * The Regents of the University of California. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * @(#)spec_vnops.c 8.15 (Berkeley) 7/14/95 */ #include __KERNEL_RCSID(0, "$NetBSD: spec_vnops.c,v 1.173.2.1 2017/07/01 08:54:08 snj Exp $"); #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* symbolic sleep message strings for devices */ const char devopn[] = "devopn"; const char devio[] = "devio"; const char devwait[] = "devwait"; const char devin[] = "devin"; const char devout[] = "devout"; const char devioc[] = "devioc"; const char devcls[] = "devcls"; #define SPECHSZ 64 #if ((SPECHSZ&(SPECHSZ-1)) == 0) #define SPECHASH(rdev) (((rdev>>5)+(rdev))&(SPECHSZ-1)) #else #define SPECHASH(rdev) (((unsigned)((rdev>>5)+(rdev)))%SPECHSZ) #endif static vnode_t *specfs_hash[SPECHSZ]; extern struct mount *dead_rootmount; /* * This vnode operations vector is used for special device nodes * created from whole cloth by the kernel. For the ops vector for * vnodes built from special devices found in a filesystem, see (e.g) * ffs_specop_entries[] in ffs_vnops.c or the equivalent for other * filesystems. */ int (**spec_vnodeop_p)(void *); const struct vnodeopv_entry_desc spec_vnodeop_entries[] = { { &vop_default_desc, vn_default_error }, { &vop_lookup_desc, spec_lookup }, /* lookup */ { &vop_create_desc, spec_create }, /* create */ { &vop_mknod_desc, spec_mknod }, /* mknod */ { &vop_open_desc, spec_open }, /* open */ { &vop_close_desc, spec_close }, /* close */ { &vop_access_desc, spec_access }, /* access */ { &vop_getattr_desc, spec_getattr }, /* getattr */ { &vop_setattr_desc, spec_setattr }, /* setattr */ { &vop_read_desc, spec_read }, /* read */ { &vop_write_desc, spec_write }, /* write */ { &vop_fallocate_desc, spec_fallocate }, /* fallocate */ { &vop_fdiscard_desc, spec_fdiscard }, /* fdiscard */ { &vop_fcntl_desc, spec_fcntl }, /* fcntl */ { &vop_ioctl_desc, spec_ioctl }, /* ioctl */ { &vop_poll_desc, spec_poll }, /* poll */ { &vop_kqfilter_desc, spec_kqfilter }, /* kqfilter */ { &vop_revoke_desc, spec_revoke }, /* revoke */ { &vop_mmap_desc, spec_mmap }, /* mmap */ { &vop_fsync_desc, spec_fsync }, /* fsync */ { &vop_seek_desc, spec_seek }, /* seek */ { &vop_remove_desc, spec_remove }, /* remove */ { &vop_link_desc, spec_link }, /* link */ { &vop_rename_desc, spec_rename }, /* rename */ { &vop_mkdir_desc, spec_mkdir }, /* mkdir */ { &vop_rmdir_desc, spec_rmdir }, /* rmdir */ { &vop_symlink_desc, spec_symlink }, /* symlink */ { &vop_readdir_desc, spec_readdir }, /* readdir */ { &vop_readlink_desc, spec_readlink }, /* readlink */ { &vop_abortop_desc, spec_abortop }, /* abortop */ { &vop_inactive_desc, spec_inactive }, /* inactive */ { &vop_reclaim_desc, spec_reclaim }, /* reclaim */ { &vop_lock_desc, spec_lock }, /* lock */ { &vop_unlock_desc, spec_unlock }, /* unlock */ { &vop_bmap_desc, spec_bmap }, /* bmap */ { &vop_strategy_desc, spec_strategy }, /* strategy */ { &vop_print_desc, spec_print }, /* print */ { &vop_islocked_desc, spec_islocked }, /* islocked */ { &vop_pathconf_desc, spec_pathconf }, /* pathconf */ { &vop_advlock_desc, spec_advlock }, /* advlock */ { &vop_bwrite_desc, spec_bwrite }, /* bwrite */ { &vop_getpages_desc, spec_getpages }, /* getpages */ { &vop_putpages_desc, spec_putpages }, /* putpages */ { NULL, NULL } }; const struct vnodeopv_desc spec_vnodeop_opv_desc = { &spec_vnodeop_p, spec_vnodeop_entries }; static kauth_listener_t rawio_listener; /* Returns true if vnode is /dev/mem or /dev/kmem. */ bool iskmemvp(struct vnode *vp) { return ((vp->v_type == VCHR) && iskmemdev(vp->v_rdev)); } /* * Returns true if dev is /dev/mem or /dev/kmem. */ int iskmemdev(dev_t dev) { /* mem_no is emitted by config(8) to generated devsw.c */ extern const int mem_no; /* minor 14 is /dev/io on i386 with COMPAT_10 */ return (major(dev) == mem_no && (minor(dev) < 2 || minor(dev) == 14)); } static int rawio_listener_cb(kauth_cred_t cred, kauth_action_t action, void *cookie, void *arg0, void *arg1, void *arg2, void *arg3) { int result; result = KAUTH_RESULT_DEFER; if ((action != KAUTH_DEVICE_RAWIO_SPEC) && (action != KAUTH_DEVICE_RAWIO_PASSTHRU)) return result; /* Access is mandated by permissions. */ result = KAUTH_RESULT_ALLOW; return result; } void spec_init(void) { rawio_listener = kauth_listen_scope(KAUTH_SCOPE_DEVICE, rawio_listener_cb, NULL); } /* * Initialize a vnode that represents a device. */ void spec_node_init(vnode_t *vp, dev_t rdev) { specnode_t *sn; specdev_t *sd; vnode_t *vp2; vnode_t **vpp; KASSERT(vp->v_type == VBLK || vp->v_type == VCHR); KASSERT(vp->v_specnode == NULL); /* * Search the hash table for this device. If known, add a * reference to the device structure. If not known, create * a new entry to represent the device. In all cases add * the vnode to the hash table. */ sn = kmem_alloc(sizeof(*sn), KM_SLEEP); sd = kmem_alloc(sizeof(*sd), KM_SLEEP); mutex_enter(&device_lock); vpp = &specfs_hash[SPECHASH(rdev)]; for (vp2 = *vpp; vp2 != NULL; vp2 = vp2->v_specnext) { KASSERT(vp2->v_specnode != NULL); if (rdev == vp2->v_rdev && vp->v_type == vp2->v_type) { break; } } if (vp2 == NULL) { /* No existing record, create a new one. */ sd->sd_rdev = rdev; sd->sd_mountpoint = NULL; sd->sd_lockf = NULL; sd->sd_refcnt = 1; sd->sd_opencnt = 0; sd->sd_bdevvp = NULL; sn->sn_dev = sd; sd = NULL; } else { /* Use the existing record. */ sn->sn_dev = vp2->v_specnode->sn_dev; sn->sn_dev->sd_refcnt++; } /* Insert vnode into the hash chain. */ sn->sn_opencnt = 0; sn->sn_rdev = rdev; sn->sn_gone = false; vp->v_specnode = sn; vp->v_specnext = *vpp; *vpp = vp; mutex_exit(&device_lock); /* Free the record we allocated if unused. */ if (sd != NULL) { kmem_free(sd, sizeof(*sd)); } } /* * Lookup a vnode by device number and return it referenced. */ int spec_node_lookup_by_dev(enum vtype type, dev_t dev, vnode_t **vpp) { int error; vnode_t *vp; mutex_enter(&device_lock); for (vp = specfs_hash[SPECHASH(dev)]; vp; vp = vp->v_specnext) { if (type == vp->v_type && dev == vp->v_rdev) { mutex_enter(vp->v_interlock); /* If clean or being cleaned, then ignore it. */ if (vdead_check(vp, VDEAD_NOWAIT) == 0) break; mutex_exit(vp->v_interlock); } } KASSERT(vp == NULL || mutex_owned(vp->v_interlock)); if (vp == NULL) { mutex_exit(&device_lock); return ENOENT; } /* * If it is an opened block device return the opened vnode. */ if (type == VBLK && vp->v_specnode->sn_dev->sd_bdevvp != NULL) { mutex_exit(vp->v_interlock); vp = vp->v_specnode->sn_dev->sd_bdevvp; mutex_enter(vp->v_interlock); } mutex_exit(&device_lock); error = vcache_vget(vp); if (error != 0) return error; *vpp = vp; return 0; } /* * Lookup a vnode by file system mounted on and return it referenced. */ int spec_node_lookup_by_mount(struct mount *mp, vnode_t **vpp) { int i, error; vnode_t *vp, *vq; mutex_enter(&device_lock); for (i = 0, vq = NULL; i < SPECHSZ && vq == NULL; i++) { for (vp = specfs_hash[i]; vp; vp = vp->v_specnext) { if (vp->v_type != VBLK) continue; vq = vp->v_specnode->sn_dev->sd_bdevvp; if (vq != NULL && vq->v_specnode->sn_dev->sd_mountpoint == mp) break; vq = NULL; } } if (vq == NULL) { mutex_exit(&device_lock); return ENOENT; } mutex_enter(vq->v_interlock); mutex_exit(&device_lock); error = vcache_vget(vq); if (error != 0) return error; *vpp = vq; return 0; } /* * Get the file system mounted on this block device. */ struct mount * spec_node_getmountedfs(vnode_t *devvp) { struct mount *mp; KASSERT(devvp->v_type == VBLK); mp = devvp->v_specnode->sn_dev->sd_mountpoint; return mp; } /* * Set the file system mounted on this block device. */ void spec_node_setmountedfs(vnode_t *devvp, struct mount *mp) { KASSERT(devvp->v_type == VBLK); KASSERT(devvp->v_specnode->sn_dev->sd_mountpoint == NULL || mp == NULL); devvp->v_specnode->sn_dev->sd_mountpoint = mp; } /* * A vnode representing a special device is going away. Close * the device if the vnode holds it open. */ void spec_node_revoke(vnode_t *vp) { specnode_t *sn; specdev_t *sd; sn = vp->v_specnode; sd = sn->sn_dev; KASSERT(vp->v_type == VBLK || vp->v_type == VCHR); KASSERT(vp->v_specnode != NULL); KASSERT(sn->sn_gone == false); mutex_enter(&device_lock); KASSERT(sn->sn_opencnt <= sd->sd_opencnt); if (sn->sn_opencnt != 0) { sd->sd_opencnt -= (sn->sn_opencnt - 1); sn->sn_opencnt = 1; sn->sn_gone = true; mutex_exit(&device_lock); VOP_CLOSE(vp, FNONBLOCK, NOCRED); mutex_enter(&device_lock); KASSERT(sn->sn_opencnt == 0); } mutex_exit(&device_lock); } /* * A vnode representing a special device is being recycled. * Destroy the specfs component. */ void spec_node_destroy(vnode_t *vp) { specnode_t *sn; specdev_t *sd; vnode_t **vpp, *vp2; int refcnt; sn = vp->v_specnode; sd = sn->sn_dev; KASSERT(vp->v_type == VBLK || vp->v_type == VCHR); KASSERT(vp->v_specnode != NULL); KASSERT(sn->sn_opencnt == 0); mutex_enter(&device_lock); /* Remove from the hash and destroy the node. */ vpp = &specfs_hash[SPECHASH(vp->v_rdev)]; for (vp2 = *vpp;; vp2 = vp2->v_specnext) { if (vp2 == NULL) { panic("spec_node_destroy: corrupt hash"); } if (vp2 == vp) { KASSERT(vp == *vpp); *vpp = vp->v_specnext; break; } if (vp2->v_specnext == vp) { vp2->v_specnext = vp->v_specnext; break; } } sn = vp->v_specnode; vp->v_specnode = NULL; refcnt = sd->sd_refcnt--; KASSERT(refcnt > 0); mutex_exit(&device_lock); /* If the device is no longer in use, destroy our record. */ if (refcnt == 1) { KASSERT(sd->sd_opencnt == 0); KASSERT(sd->sd_bdevvp == NULL); kmem_free(sd, sizeof(*sd)); } kmem_free(sn, sizeof(*sn)); } /* * Trivial lookup routine that always fails. */ int spec_lookup(void *v) { struct vop_lookup_v2_args /* { struct vnode *a_dvp; struct vnode **a_vpp; struct componentname *a_cnp; } */ *ap = v; *ap->a_vpp = NULL; return (ENOTDIR); } typedef int (*spec_ioctl_t)(dev_t, u_long, void *, int, struct lwp *); /* * Open a special file. */ /* ARGSUSED */ int spec_open(void *v) { struct vop_open_args /* { struct vnode *a_vp; int a_mode; kauth_cred_t a_cred; } */ *ap = v; struct lwp *l; struct vnode *vp; dev_t dev; int error; enum kauth_device_req req; specnode_t *sn; specdev_t *sd; spec_ioctl_t ioctl; u_int gen; const char *name; struct partinfo pi; l = curlwp; vp = ap->a_vp; dev = vp->v_rdev; sn = vp->v_specnode; sd = sn->sn_dev; name = NULL; gen = 0; /* * Don't allow open if fs is mounted -nodev. */ if (vp->v_mount && (vp->v_mount->mnt_flag & MNT_NODEV)) return (ENXIO); switch (ap->a_mode & (FREAD | FWRITE)) { case FREAD | FWRITE: req = KAUTH_REQ_DEVICE_RAWIO_SPEC_RW; break; case FWRITE: req = KAUTH_REQ_DEVICE_RAWIO_SPEC_WRITE; break; default: req = KAUTH_REQ_DEVICE_RAWIO_SPEC_READ; break; } switch (vp->v_type) { case VCHR: error = kauth_authorize_device_spec(ap->a_cred, req, vp); if (error != 0) return (error); /* * Character devices can accept opens from multiple * vnodes. */ mutex_enter(&device_lock); if (sn->sn_gone) { mutex_exit(&device_lock); return (EBADF); } sd->sd_opencnt++; sn->sn_opencnt++; mutex_exit(&device_lock); if (cdev_type(dev) == D_TTY) vp->v_vflag |= VV_ISTTY; VOP_UNLOCK(vp); do { const struct cdevsw *cdev; gen = module_gen; error = cdev_open(dev, ap->a_mode, S_IFCHR, l); if (error != ENXIO) break; /* Check if we already have a valid driver */ mutex_enter(&device_lock); cdev = cdevsw_lookup(dev); mutex_exit(&device_lock); if (cdev != NULL) break; /* Get device name from devsw_conv array */ if ((name = cdevsw_getname(major(dev))) == NULL) break; /* Try to autoload device module */ (void) module_autoload(name, MODULE_CLASS_DRIVER); } while (gen != module_gen); vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); break; case VBLK: error = kauth_authorize_device_spec(ap->a_cred, req, vp); if (error != 0) return (error); /* * For block devices, permit only one open. The buffer * cache cannot remain self-consistent with multiple * vnodes holding a block device open. * * Treat zero opencnt with non-NULL mountpoint as open. * This may happen after forced detach of a mounted device. */ mutex_enter(&device_lock); if (sn->sn_gone) { mutex_exit(&device_lock); return (EBADF); } if (sd->sd_opencnt != 0 || sd->sd_mountpoint != NULL) { mutex_exit(&device_lock); return EBUSY; } sn->sn_opencnt = 1; sd->sd_opencnt = 1; sd->sd_bdevvp = vp; mutex_exit(&device_lock); do { const struct bdevsw *bdev; gen = module_gen; error = bdev_open(dev, ap->a_mode, S_IFBLK, l); if (error != ENXIO) break; /* Check if we already have a valid driver */ mutex_enter(&device_lock); bdev = bdevsw_lookup(dev); mutex_exit(&device_lock); if (bdev != NULL) break; /* Get device name from devsw_conv array */ if ((name = bdevsw_getname(major(dev))) == NULL) break; VOP_UNLOCK(vp); /* Try to autoload device module */ (void) module_autoload(name, MODULE_CLASS_DRIVER); vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); } while (gen != module_gen); break; case VNON: case VLNK: case VDIR: case VREG: case VBAD: case VFIFO: case VSOCK: default: return 0; } mutex_enter(&device_lock); if (sn->sn_gone) { if (error == 0) error = EBADF; } else if (error != 0) { sd->sd_opencnt--; sn->sn_opencnt--; if (vp->v_type == VBLK) sd->sd_bdevvp = NULL; } mutex_exit(&device_lock); if (cdev_type(dev) != D_DISK || error != 0) return error; ioctl = vp->v_type == VCHR ? cdev_ioctl : bdev_ioctl; error = (*ioctl)(vp->v_rdev, DIOCGPARTINFO, &pi, FREAD, curlwp); if (error == 0) uvm_vnp_setsize(vp, (voff_t)pi.pi_secsize * pi.pi_size); return 0; } /* * Vnode op for read */ /* ARGSUSED */ int spec_read(void *v) { struct vop_read_args /* { struct vnode *a_vp; struct uio *a_uio; int a_ioflag; kauth_cred_t a_cred; } */ *ap = v; struct vnode *vp = ap->a_vp; struct uio *uio = ap->a_uio; struct lwp *l = curlwp; struct buf *bp; daddr_t bn; int bsize, bscale; struct partinfo pi; int n, on; int error = 0; KASSERT(uio->uio_rw == UIO_READ); KASSERTMSG(VMSPACE_IS_KERNEL_P(uio->uio_vmspace) || uio->uio_vmspace == curproc->p_vmspace, "vmspace belongs to neither kernel nor curproc"); if (uio->uio_resid == 0) return (0); switch (vp->v_type) { case VCHR: VOP_UNLOCK(vp); error = cdev_read(vp->v_rdev, uio, ap->a_ioflag); vn_lock(vp, LK_SHARED | LK_RETRY); return (error); case VBLK: KASSERT(vp == vp->v_specnode->sn_dev->sd_bdevvp); if (uio->uio_offset < 0) return (EINVAL); if (bdev_ioctl(vp->v_rdev, DIOCGPARTINFO, &pi, FREAD, l) == 0) bsize = pi.pi_bsize; else bsize = BLKDEV_IOSIZE; bscale = bsize >> DEV_BSHIFT; do { bn = (uio->uio_offset >> DEV_BSHIFT) &~ (bscale - 1); on = uio->uio_offset % bsize; n = min((unsigned)(bsize - on), uio->uio_resid); error = bread(vp, bn, bsize, 0, &bp); if (error) { return (error); } n = min(n, bsize - bp->b_resid); error = uiomove((char *)bp->b_data + on, n, uio); brelse(bp, 0); } while (error == 0 && uio->uio_resid > 0 && n != 0); return (error); default: panic("spec_read type"); } /* NOTREACHED */ } /* * Vnode op for write */ /* ARGSUSED */ int spec_write(void *v) { struct vop_write_args /* { struct vnode *a_vp; struct uio *a_uio; int a_ioflag; kauth_cred_t a_cred; } */ *ap = v; struct vnode *vp = ap->a_vp; struct uio *uio = ap->a_uio; struct lwp *l = curlwp; struct buf *bp; daddr_t bn; int bsize, bscale; struct partinfo pi; int n, on; int error = 0; KASSERT(uio->uio_rw == UIO_WRITE); KASSERTMSG(VMSPACE_IS_KERNEL_P(uio->uio_vmspace) || uio->uio_vmspace == curproc->p_vmspace, "vmspace belongs to neither kernel nor curproc"); switch (vp->v_type) { case VCHR: VOP_UNLOCK(vp); error = cdev_write(vp->v_rdev, uio, ap->a_ioflag); vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); return (error); case VBLK: KASSERT(vp == vp->v_specnode->sn_dev->sd_bdevvp); if (uio->uio_resid == 0) return (0); if (uio->uio_offset < 0) return (EINVAL); if (bdev_ioctl(vp->v_rdev, DIOCGPARTINFO, &pi, FREAD, l) == 0) bsize = pi.pi_bsize; else bsize = BLKDEV_IOSIZE; bscale = bsize >> DEV_BSHIFT; do { bn = (uio->uio_offset >> DEV_BSHIFT) &~ (bscale - 1); on = uio->uio_offset % bsize; n = min((unsigned)(bsize - on), uio->uio_resid); if (n == bsize) bp = getblk(vp, bn, bsize, 0, 0); else error = bread(vp, bn, bsize, B_MODIFY, &bp); if (error) { return (error); } n = min(n, bsize - bp->b_resid); error = uiomove((char *)bp->b_data + on, n, uio); if (error) brelse(bp, 0); else { if (n + on == bsize) bawrite(bp); else bdwrite(bp); error = bp->b_error; } } while (error == 0 && uio->uio_resid > 0 && n != 0); return (error); default: panic("spec_write type"); } /* NOTREACHED */ } /* * fdiscard, which on disk devices becomes TRIM. */ int spec_fdiscard(void *v) { struct vop_fdiscard_args /* { struct vnode *a_vp; off_t a_pos; off_t a_len; } */ *ap = v; struct vnode *vp; dev_t dev; vp = ap->a_vp; dev = NODEV; mutex_enter(vp->v_interlock); if (vdead_check(vp, VDEAD_NOWAIT) == 0 && vp->v_specnode != NULL) { dev = vp->v_rdev; } mutex_exit(vp->v_interlock); if (dev == NODEV) { return ENXIO; } switch (vp->v_type) { case VCHR: // this is not stored for character devices //KASSERT(vp == vp->v_specnode->sn_dev->sd_cdevvp); return cdev_discard(dev, ap->a_pos, ap->a_len); case VBLK: KASSERT(vp == vp->v_specnode->sn_dev->sd_bdevvp); return bdev_discard(dev, ap->a_pos, ap->a_len); default: panic("spec_fdiscard: not a device\n"); } } /* * Device ioctl operation. */ /* ARGSUSED */ int spec_ioctl(void *v) { struct vop_ioctl_args /* { struct vnode *a_vp; u_long a_command; void *a_data; int a_fflag; kauth_cred_t a_cred; } */ *ap = v; struct vnode *vp; dev_t dev; /* * Extract all the info we need from the vnode, taking care to * avoid a race with VOP_REVOKE(). */ vp = ap->a_vp; dev = NODEV; mutex_enter(vp->v_interlock); if (vdead_check(vp, VDEAD_NOWAIT) == 0 && vp->v_specnode) { dev = vp->v_rdev; } mutex_exit(vp->v_interlock); if (dev == NODEV) { return ENXIO; } switch (vp->v_type) { case VCHR: return cdev_ioctl(dev, ap->a_command, ap->a_data, ap->a_fflag, curlwp); case VBLK: KASSERT(vp == vp->v_specnode->sn_dev->sd_bdevvp); return bdev_ioctl(dev, ap->a_command, ap->a_data, ap->a_fflag, curlwp); default: panic("spec_ioctl"); /* NOTREACHED */ } } /* ARGSUSED */ int spec_poll(void *v) { struct vop_poll_args /* { struct vnode *a_vp; int a_events; } */ *ap = v; struct vnode *vp; dev_t dev; /* * Extract all the info we need from the vnode, taking care to * avoid a race with VOP_REVOKE(). */ vp = ap->a_vp; dev = NODEV; mutex_enter(vp->v_interlock); if (vdead_check(vp, VDEAD_NOWAIT) == 0 && vp->v_specnode) { dev = vp->v_rdev; } mutex_exit(vp->v_interlock); if (dev == NODEV) { return POLLERR; } switch (vp->v_type) { case VCHR: return cdev_poll(dev, ap->a_events, curlwp); default: return (genfs_poll(v)); } } /* ARGSUSED */ int spec_kqfilter(void *v) { struct vop_kqfilter_args /* { struct vnode *a_vp; struct proc *a_kn; } */ *ap = v; dev_t dev; switch (ap->a_vp->v_type) { case VCHR: dev = ap->a_vp->v_rdev; return cdev_kqfilter(dev, ap->a_kn); default: /* * Block devices don't support kqfilter, and refuse it * for any other files (like those vflush()ed) too. */ return (EOPNOTSUPP); } } /* * Allow mapping of only D_DISK. This is called only for VBLK. */ int spec_mmap(void *v) { struct vop_mmap_args /* { struct vnode *a_vp; vm_prot_t a_prot; kauth_cred_t a_cred; } */ *ap = v; struct vnode *vp = ap->a_vp; KASSERT(vp->v_type == VBLK); if (bdev_type(vp->v_rdev) != D_DISK) return EINVAL; return 0; } /* * Synch buffers associated with a block device */ /* ARGSUSED */ int spec_fsync(void *v) { struct vop_fsync_args /* { struct vnode *a_vp; kauth_cred_t a_cred; int a_flags; off_t offlo; off_t offhi; } */ *ap = v; struct vnode *vp = ap->a_vp; struct mount *mp; int error; if (vp->v_type == VBLK) { if ((mp = spec_node_getmountedfs(vp)) != NULL) { error = VFS_FSYNC(mp, vp, ap->a_flags); if (error != EOPNOTSUPP) return error; } return vflushbuf(vp, ap->a_flags); } return (0); } /* * Just call the device strategy routine */ int spec_strategy(void *v) { struct vop_strategy_args /* { struct vnode *a_vp; struct buf *a_bp; } */ *ap = v; struct vnode *vp = ap->a_vp; struct buf *bp = ap->a_bp; dev_t dev; int error; dev = NODEV; /* * Extract all the info we need from the vnode, taking care to * avoid a race with VOP_REVOKE(). */ mutex_enter(vp->v_interlock); if (vdead_check(vp, VDEAD_NOWAIT) == 0 && vp->v_specnode != NULL) { KASSERT(vp == vp->v_specnode->sn_dev->sd_bdevvp); dev = vp->v_rdev; } mutex_exit(vp->v_interlock); if (dev == NODEV) { error = ENXIO; goto out; } bp->b_dev = dev; if (!(bp->b_flags & B_READ)) { #ifdef DIAGNOSTIC if (bp->b_vp && bp->b_vp->v_type == VBLK) { struct mount *mp = spec_node_getmountedfs(bp->b_vp); if (mp && (mp->mnt_flag & MNT_RDONLY)) { printf("%s blk %"PRId64" written while ro!\n", mp->mnt_stat.f_mntonname, bp->b_blkno); } } #endif /* DIAGNOSTIC */ error = fscow_run(bp, false); if (error) goto out; } bdev_strategy(bp); return 0; out: bp->b_error = error; bp->b_resid = bp->b_bcount; biodone(bp); return error; } int spec_inactive(void *v) { struct vop_inactive_v2_args /* { struct vnode *a_vp; struct bool *a_recycle; } */ *ap = v; KASSERT(ap->a_vp->v_mount == dead_rootmount); *ap->a_recycle = true; return 0; } int spec_reclaim(void *v) { struct vop_reclaim_v2_args /* { struct vnode *a_vp; } */ *ap = v; struct vnode *vp = ap->a_vp; VOP_UNLOCK(vp); KASSERT(vp->v_mount == dead_rootmount); return 0; } /* * This is a noop, simply returning what one has been given. */ int spec_bmap(void *v) { struct vop_bmap_args /* { struct vnode *a_vp; daddr_t a_bn; struct vnode **a_vpp; daddr_t *a_bnp; int *a_runp; } */ *ap = v; if (ap->a_vpp != NULL) *ap->a_vpp = ap->a_vp; if (ap->a_bnp != NULL) *ap->a_bnp = ap->a_bn; if (ap->a_runp != NULL) *ap->a_runp = (MAXBSIZE >> DEV_BSHIFT) - 1; return (0); } /* * Device close routine */ /* ARGSUSED */ int spec_close(void *v) { struct vop_close_args /* { struct vnode *a_vp; int a_fflag; kauth_cred_t a_cred; } */ *ap = v; struct vnode *vp = ap->a_vp; struct session *sess; dev_t dev = vp->v_rdev; int flags = ap->a_fflag; int mode, error, count; specnode_t *sn; specdev_t *sd; mutex_enter(vp->v_interlock); sn = vp->v_specnode; sd = sn->sn_dev; /* * If we're going away soon, make this non-blocking. * Also ensures that we won't wedge in vn_lock below. */ if (vdead_check(vp, VDEAD_NOWAIT) != 0) flags |= FNONBLOCK; mutex_exit(vp->v_interlock); switch (vp->v_type) { case VCHR: /* * Hack: a tty device that is a controlling terminal * has a reference from the session structure. We * cannot easily tell that a character device is a * controlling terminal, unless it is the closing * process' controlling terminal. In that case, if the * open count is 1 release the reference from the * session. Also, remove the link from the tty back to * the session and pgrp. * * XXX V. fishy. */ mutex_enter(proc_lock); sess = curlwp->l_proc->p_session; if (sn->sn_opencnt == 1 && vp == sess->s_ttyvp) { mutex_spin_enter(&tty_lock); sess->s_ttyvp = NULL; if (sess->s_ttyp->t_session != NULL) { sess->s_ttyp->t_pgrp = NULL; sess->s_ttyp->t_session = NULL; mutex_spin_exit(&tty_lock); /* Releases proc_lock. */ proc_sessrele(sess); } else { mutex_spin_exit(&tty_lock); if (sess->s_ttyp->t_pgrp != NULL) panic("spec_close: spurious pgrp ref"); mutex_exit(proc_lock); } vrele(vp); } else mutex_exit(proc_lock); /* * If the vnode is locked, then we are in the midst * of forcably closing the device, otherwise we only * close on last reference. */ mode = S_IFCHR; break; case VBLK: KASSERT(vp == vp->v_specnode->sn_dev->sd_bdevvp); /* * On last close of a block device (that isn't mounted) * we must invalidate any in core blocks, so that * we can, for instance, change floppy disks. */ error = vinvalbuf(vp, V_SAVE, ap->a_cred, curlwp, 0, 0); if (error) return (error); /* * We do not want to really close the device if it * is still in use unless we are trying to close it * forcibly. Since every use (buffer, vnode, swap, cmap) * holds a reference to the vnode, and because we mark * any other vnodes that alias this device, when the * sum of the reference counts on all the aliased * vnodes descends to one, we are on last close. */ mode = S_IFBLK; break; default: panic("spec_close: not special"); } mutex_enter(&device_lock); sn->sn_opencnt--; count = --sd->sd_opencnt; if (vp->v_type == VBLK) sd->sd_bdevvp = NULL; mutex_exit(&device_lock); if (count != 0 && (vp->v_type != VCHR || !(cdev_flags(dev) & D_MCLOSE))) return 0; /* * If we're able to block, release the vnode lock & reacquire. We * might end up sleeping for someone else who wants our queues. They * won't get them if we hold the vnode locked. */ if (!(flags & FNONBLOCK)) VOP_UNLOCK(vp); if (vp->v_type == VBLK) error = bdev_close(dev, flags, mode, curlwp); else error = cdev_close(dev, flags, mode, curlwp); if (!(flags & FNONBLOCK)) vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); return (error); } /* * Print out the contents of a special device vnode. */ int spec_print(void *v) { struct vop_print_args /* { struct vnode *a_vp; } */ *ap = v; printf("dev %llu, %llu\n", (unsigned long long)major(ap->a_vp->v_rdev), (unsigned long long)minor(ap->a_vp->v_rdev)); return 0; } /* * Return POSIX pathconf information applicable to special devices. */ int spec_pathconf(void *v) { struct vop_pathconf_args /* { struct vnode *a_vp; int a_name; register_t *a_retval; } */ *ap = v; switch (ap->a_name) { case _PC_LINK_MAX: *ap->a_retval = LINK_MAX; return (0); case _PC_MAX_CANON: *ap->a_retval = MAX_CANON; return (0); case _PC_MAX_INPUT: *ap->a_retval = MAX_INPUT; return (0); case _PC_PIPE_BUF: *ap->a_retval = PIPE_BUF; return (0); case _PC_CHOWN_RESTRICTED: *ap->a_retval = 1; return (0); case _PC_VDISABLE: *ap->a_retval = _POSIX_VDISABLE; return (0); case _PC_SYNC_IO: *ap->a_retval = 1; return (0); default: return (EINVAL); } /* NOTREACHED */ } /* * Advisory record locking support. */ int spec_advlock(void *v) { struct vop_advlock_args /* { struct vnode *a_vp; void *a_id; int a_op; struct flock *a_fl; int a_flags; } */ *ap = v; struct vnode *vp = ap->a_vp; return lf_advlock(ap, &vp->v_speclockf, (off_t)0); }