1/*-
2 * Copyright (c) 1992, 1993, 1995
3 * The Regents of the University of California. All rights reserved.
4 *
5 * This code is derived from software donated to Berkeley by
6 * Jan-Simon Pendry.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 4. Neither the name of the University nor the names of its contributors
17 * may be used to endorse or promote products derived from this software
18 * without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 *
32 * @(#)fdesc_vfsops.c 8.4 (Berkeley) 1/21/94
33 *
| 1/*-
2 * Copyright (c) 1992, 1993, 1995
3 * The Regents of the University of California. All rights reserved.
4 *
5 * This code is derived from software donated to Berkeley by
6 * Jan-Simon Pendry.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 4. Neither the name of the University nor the names of its contributors
17 * may be used to endorse or promote products derived from this software
18 * without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 *
32 * @(#)fdesc_vfsops.c 8.4 (Berkeley) 1/21/94
33 *
|
34 * $FreeBSD: head/sys/fs/fdescfs/fdesc_vfsops.c 172697 2007-10-16 10:54:55Z alfred $
| 34 * $FreeBSD: head/sys/fs/fdescfs/fdesc_vfsops.c 175202 2008-01-10 01:10:58Z attilio $
|
35 */
36
37/*
38 * /dev/fd Filesystem
39 */
40
41#include <sys/param.h>
42#include <sys/systm.h>
43#include <sys/filedesc.h>
44#include <sys/kernel.h>
45#include <sys/lock.h>
46#include <sys/mutex.h>
47#include <sys/malloc.h>
48#include <sys/mount.h>
49#include <sys/proc.h>
50#include <sys/resourcevar.h>
51#include <sys/vnode.h>
52
53#include <fs/fdescfs/fdesc.h>
54
55static MALLOC_DEFINE(M_FDESCMNT, "fdesc_mount", "FDESC mount structure");
56
57static vfs_cmount_t fdesc_cmount;
58static vfs_mount_t fdesc_mount;
59static vfs_unmount_t fdesc_unmount;
60static vfs_statfs_t fdesc_statfs;
61static vfs_root_t fdesc_root;
62
63/*
64 * Compatibility shim for old mount(2) system call.
65 */
66int
67fdesc_cmount(struct mntarg *ma, void *data, int flags, struct thread *td)
68{
69 return kernel_mount(ma, flags);
70}
71
72/*
73 * Mount the per-process file descriptors (/dev/fd)
74 */
75static int
76fdesc_mount(struct mount *mp, struct thread *td)
77{
78 int error = 0;
79 struct fdescmount *fmp;
80 struct vnode *rvp;
81
82 /*
83 * Update is a no-op
84 */
85 if (mp->mnt_flag & (MNT_UPDATE | MNT_ROOTFS))
86 return (EOPNOTSUPP);
87
88 error = fdesc_allocvp(Froot, FD_ROOT, mp, &rvp, td);
89 if (error)
90 return (error);
91
92 MALLOC(fmp, struct fdescmount *, sizeof(struct fdescmount),
93 M_FDESCMNT, M_WAITOK); /* XXX */
94 rvp->v_type = VDIR;
95 rvp->v_vflag |= VV_ROOT;
96 fmp->f_root = rvp;
97 /* XXX -- don't mark as local to work around fts() problems */
98 /*mp->mnt_flag |= MNT_LOCAL;*/
99 mp->mnt_data = fmp;
100 vfs_getnewfsid(mp);
101
102 vfs_mountedfrom(mp, "fdescfs");
103 return (0);
104}
105
106static int
107fdesc_unmount(mp, mntflags, td)
108 struct mount *mp;
109 int mntflags;
110 struct thread *td;
111{
112 int error;
113 int flags = 0;
114
115 if (mntflags & MNT_FORCE)
116 flags |= FORCECLOSE;
117
118 /*
119 * Clear out buffer cache. I don't think we
120 * ever get anything cached at this level at the
121 * moment, but who knows...
122 *
123 * There is 1 extra root vnode reference corresponding
124 * to f_root.
125 */
126 if ((error = vflush(mp, 1, flags, td)) != 0)
127 return (error);
128
129 /*
130 * Finally, throw away the fdescmount structure
131 */
132 free(mp->mnt_data, M_FDESCMNT); /* XXX */
133 mp->mnt_data = 0;
134
135 return (0);
136}
137
138static int
139fdesc_root(mp, flags, vpp, td)
140 struct mount *mp;
141 int flags;
142 struct vnode **vpp;
143 struct thread *td;
144{
145 struct vnode *vp;
146
147 /*
148 * Return locked reference to root.
149 */
150 vp = VFSTOFDESC(mp)->f_root;
151 VREF(vp);
| 35 */
36
37/*
38 * /dev/fd Filesystem
39 */
40
41#include <sys/param.h>
42#include <sys/systm.h>
43#include <sys/filedesc.h>
44#include <sys/kernel.h>
45#include <sys/lock.h>
46#include <sys/mutex.h>
47#include <sys/malloc.h>
48#include <sys/mount.h>
49#include <sys/proc.h>
50#include <sys/resourcevar.h>
51#include <sys/vnode.h>
52
53#include <fs/fdescfs/fdesc.h>
54
55static MALLOC_DEFINE(M_FDESCMNT, "fdesc_mount", "FDESC mount structure");
56
57static vfs_cmount_t fdesc_cmount;
58static vfs_mount_t fdesc_mount;
59static vfs_unmount_t fdesc_unmount;
60static vfs_statfs_t fdesc_statfs;
61static vfs_root_t fdesc_root;
62
63/*
64 * Compatibility shim for old mount(2) system call.
65 */
66int
67fdesc_cmount(struct mntarg *ma, void *data, int flags, struct thread *td)
68{
69 return kernel_mount(ma, flags);
70}
71
72/*
73 * Mount the per-process file descriptors (/dev/fd)
74 */
75static int
76fdesc_mount(struct mount *mp, struct thread *td)
77{
78 int error = 0;
79 struct fdescmount *fmp;
80 struct vnode *rvp;
81
82 /*
83 * Update is a no-op
84 */
85 if (mp->mnt_flag & (MNT_UPDATE | MNT_ROOTFS))
86 return (EOPNOTSUPP);
87
88 error = fdesc_allocvp(Froot, FD_ROOT, mp, &rvp, td);
89 if (error)
90 return (error);
91
92 MALLOC(fmp, struct fdescmount *, sizeof(struct fdescmount),
93 M_FDESCMNT, M_WAITOK); /* XXX */
94 rvp->v_type = VDIR;
95 rvp->v_vflag |= VV_ROOT;
96 fmp->f_root = rvp;
97 /* XXX -- don't mark as local to work around fts() problems */
98 /*mp->mnt_flag |= MNT_LOCAL;*/
99 mp->mnt_data = fmp;
100 vfs_getnewfsid(mp);
101
102 vfs_mountedfrom(mp, "fdescfs");
103 return (0);
104}
105
106static int
107fdesc_unmount(mp, mntflags, td)
108 struct mount *mp;
109 int mntflags;
110 struct thread *td;
111{
112 int error;
113 int flags = 0;
114
115 if (mntflags & MNT_FORCE)
116 flags |= FORCECLOSE;
117
118 /*
119 * Clear out buffer cache. I don't think we
120 * ever get anything cached at this level at the
121 * moment, but who knows...
122 *
123 * There is 1 extra root vnode reference corresponding
124 * to f_root.
125 */
126 if ((error = vflush(mp, 1, flags, td)) != 0)
127 return (error);
128
129 /*
130 * Finally, throw away the fdescmount structure
131 */
132 free(mp->mnt_data, M_FDESCMNT); /* XXX */
133 mp->mnt_data = 0;
134
135 return (0);
136}
137
138static int
139fdesc_root(mp, flags, vpp, td)
140 struct mount *mp;
141 int flags;
142 struct vnode **vpp;
143 struct thread *td;
144{
145 struct vnode *vp;
146
147 /*
148 * Return locked reference to root.
149 */
150 vp = VFSTOFDESC(mp)->f_root;
151 VREF(vp);
|
152 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, td);
| 152 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
|
153 *vpp = vp;
154 return (0);
155}
156
157static int
158fdesc_statfs(mp, sbp, td)
159 struct mount *mp;
160 struct statfs *sbp;
161 struct thread *td;
162{
163 struct filedesc *fdp;
164 int lim;
165 int i;
166 int last;
167 int freefd;
168
169 /*
170 * Compute number of free file descriptors.
171 * [ Strange results will ensue if the open file
172 * limit is ever reduced below the current number
173 * of open files... ]
174 */
175 PROC_LOCK(td->td_proc);
176 lim = lim_cur(td->td_proc, RLIMIT_NOFILE);
177 PROC_UNLOCK(td->td_proc);
178 fdp = td->td_proc->p_fd;
179 FILEDESC_SLOCK(fdp);
180 last = min(fdp->fd_nfiles, lim);
181 freefd = 0;
182 for (i = fdp->fd_freefile; i < last; i++)
183 if (fdp->fd_ofiles[i] == NULL)
184 freefd++;
185
186 /*
187 * Adjust for the fact that the fdesc array may not
188 * have been fully allocated yet.
189 */
190 if (fdp->fd_nfiles < lim)
191 freefd += (lim - fdp->fd_nfiles);
192 FILEDESC_SUNLOCK(fdp);
193
194 sbp->f_flags = 0;
195 sbp->f_bsize = DEV_BSIZE;
196 sbp->f_iosize = DEV_BSIZE;
197 sbp->f_blocks = 2; /* 1K to keep df happy */
198 sbp->f_bfree = 0;
199 sbp->f_bavail = 0;
200 sbp->f_files = lim + 1; /* Allow for "." */
201 sbp->f_ffree = freefd; /* See comments above */
202 return (0);
203}
204
205static struct vfsops fdesc_vfsops = {
206 .vfs_cmount = fdesc_cmount,
207 .vfs_init = fdesc_init,
208 .vfs_mount = fdesc_mount,
209 .vfs_root = fdesc_root,
210 .vfs_statfs = fdesc_statfs,
211 .vfs_unmount = fdesc_unmount,
212};
213
214VFS_SET(fdesc_vfsops, fdescfs, VFCF_SYNTHETIC);
| 153 *vpp = vp;
154 return (0);
155}
156
157static int
158fdesc_statfs(mp, sbp, td)
159 struct mount *mp;
160 struct statfs *sbp;
161 struct thread *td;
162{
163 struct filedesc *fdp;
164 int lim;
165 int i;
166 int last;
167 int freefd;
168
169 /*
170 * Compute number of free file descriptors.
171 * [ Strange results will ensue if the open file
172 * limit is ever reduced below the current number
173 * of open files... ]
174 */
175 PROC_LOCK(td->td_proc);
176 lim = lim_cur(td->td_proc, RLIMIT_NOFILE);
177 PROC_UNLOCK(td->td_proc);
178 fdp = td->td_proc->p_fd;
179 FILEDESC_SLOCK(fdp);
180 last = min(fdp->fd_nfiles, lim);
181 freefd = 0;
182 for (i = fdp->fd_freefile; i < last; i++)
183 if (fdp->fd_ofiles[i] == NULL)
184 freefd++;
185
186 /*
187 * Adjust for the fact that the fdesc array may not
188 * have been fully allocated yet.
189 */
190 if (fdp->fd_nfiles < lim)
191 freefd += (lim - fdp->fd_nfiles);
192 FILEDESC_SUNLOCK(fdp);
193
194 sbp->f_flags = 0;
195 sbp->f_bsize = DEV_BSIZE;
196 sbp->f_iosize = DEV_BSIZE;
197 sbp->f_blocks = 2; /* 1K to keep df happy */
198 sbp->f_bfree = 0;
199 sbp->f_bavail = 0;
200 sbp->f_files = lim + 1; /* Allow for "." */
201 sbp->f_ffree = freefd; /* See comments above */
202 return (0);
203}
204
205static struct vfsops fdesc_vfsops = {
206 .vfs_cmount = fdesc_cmount,
207 .vfs_init = fdesc_init,
208 .vfs_mount = fdesc_mount,
209 .vfs_root = fdesc_root,
210 .vfs_statfs = fdesc_statfs,
211 .vfs_unmount = fdesc_unmount,
212};
213
214VFS_SET(fdesc_vfsops, fdescfs, VFCF_SYNTHETIC);
|