2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
4 * Copyright (c) 1992, 1993, 1995
5 * The Regents of the University of California. All rights reserved.
7 * Poul-Henning Kamp. All rights reserved.
9 * This code is derived from software donated to Berkeley by
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13 * modification, are permitted provided that the following conditions
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23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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33 * @(#)kernfs_vfsops.c 8.10 (Berkeley) 5/14/95
34 * From: FreeBSD: src/sys/miscfs/kernfs/kernfs_vfsops.c 1.36
39 #include <sys/param.h>
40 #include <sys/systm.h>
41 #include <sys/kernel.h>
43 #include <sys/malloc.h>
44 #include <sys/mount.h>
47 #include <sys/vnode.h>
48 #include <sys/limits.h>
51 #include <fs/devfs/devfs.h>
53 static struct unrhdr *devfs_unr;
55 MALLOC_DEFINE(M_DEVFS, "DEVFS", "DEVFS data");
57 static vfs_mount_t devfs_mount;
58 static vfs_unmount_t devfs_unmount;
59 static vfs_root_t devfs_root;
60 static vfs_statfs_t devfs_statfs;
62 static const char *devfs_opts[] = {
63 "from", "export", "ruleset", NULL
67 * Mount the filesystem
70 devfs_mount(struct mount *mp)
73 struct devfs_mount *fmp;
75 struct thread *td = curthread;
78 if (devfs_unr == NULL)
79 devfs_unr = new_unrhdr(0, INT_MAX, NULL);
83 if (mp->mnt_flag & MNT_ROOTFS)
87 injail = jailed(td->td_ucred);
89 if (mp->mnt_optnew != NULL) {
90 if (vfs_filteropt(mp->mnt_optnew, devfs_opts))
93 if (vfs_flagopt(mp->mnt_optnew, "export", NULL, 0))
96 if (vfs_getopt(mp->mnt_optnew, "ruleset", NULL, NULL) == 0 &&
97 (vfs_scanopt(mp->mnt_optnew, "ruleset", "%d",
98 &rsnum) != 1 || rsnum < 0 || rsnum > 65535)) {
99 vfs_mount_error(mp, "%s",
100 "invalid ruleset specification");
104 if (injail && rsnum != 0 &&
105 rsnum != td->td_ucred->cr_prison->pr_devfs_rsnum)
109 /* jails enforce their ruleset */
111 rsnum = td->td_ucred->cr_prison->pr_devfs_rsnum;
113 if (mp->mnt_flag & MNT_UPDATE) {
117 sx_xlock(&fmp->dm_lock);
118 devfs_ruleset_set((devfs_rsnum)rsnum, fmp);
119 devfs_ruleset_apply(fmp);
120 sx_xunlock(&fmp->dm_lock);
126 fmp = malloc(sizeof *fmp, M_DEVFS, M_WAITOK | M_ZERO);
127 fmp->dm_idx = alloc_unr(devfs_unr);
128 sx_init(&fmp->dm_lock, "devfsmount");
132 mp->mnt_flag |= MNT_LOCAL;
133 mp->mnt_kern_flag |= MNTK_LOOKUP_SHARED | MNTK_EXTENDED_SHARED |
136 mp->mnt_flag |= MNT_MULTILABEL;
140 mp->mnt_data = (void *) fmp;
143 fmp->dm_rootdir = devfs_vmkdir(fmp, NULL, 0, NULL, DEVFS_ROOTINO);
145 error = devfs_root(mp, LK_EXCLUSIVE, &rvp);
147 sx_destroy(&fmp->dm_lock);
148 free_unr(devfs_unr, fmp->dm_idx);
154 sx_xlock(&fmp->dm_lock);
155 devfs_ruleset_set((devfs_rsnum)rsnum, fmp);
156 sx_xunlock(&fmp->dm_lock);
160 vfs_cache_root_set(mp, rvp);
162 vfs_mountedfrom(mp, "devfs");
168 devfs_unmount_final(struct devfs_mount *fmp)
170 sx_destroy(&fmp->dm_lock);
175 devfs_unmount(struct mount *mp, int mntflags)
179 struct devfs_mount *fmp;
183 fmp = VFSTODEVFS(mp);
184 KASSERT(fmp->dm_mount != NULL,
185 ("devfs_unmount unmounted devfs_mount"));
186 if (mntflags & MNT_FORCE)
188 /* There is 1 extra root vnode reference from devfs_mount(). */
189 error = vflush(mp, 1, flags, curthread);
192 sx_xlock(&fmp->dm_lock);
194 devfs_rules_cleanup(fmp);
195 fmp->dm_mount = NULL;
196 hold = --fmp->dm_holdcnt;
199 sx_xunlock(&fmp->dm_lock);
200 free_unr(devfs_unr, idx);
202 devfs_unmount_final(fmp);
206 /* Return locked reference to root. */
209 devfs_root(struct mount *mp, int flags, struct vnode **vpp)
213 struct devfs_mount *dmp;
215 dmp = VFSTODEVFS(mp);
216 sx_xlock(&dmp->dm_lock);
217 error = devfs_allocv(dmp->dm_rootdir, mp, LK_EXCLUSIVE, &vp);
220 vp->v_vflag |= VV_ROOT;
226 devfs_statfs(struct mount *mp, struct statfs *sbp)
230 sbp->f_bsize = DEV_BSIZE;
231 sbp->f_iosize = DEV_BSIZE;
232 sbp->f_blocks = 2; /* 1K to keep df happy */
240 static struct vfsops devfs_vfsops = {
241 .vfs_mount = devfs_mount,
242 .vfs_root = vfs_cache_root,
243 .vfs_cachedroot = devfs_root,
244 .vfs_statfs = devfs_statfs,
245 .vfs_unmount = devfs_unmount,
248 VFS_SET(devfs_vfsops, devfs, VFCF_SYNTHETIC | VFCF_JAIL);