2 * Copyright (c) 2000 Dag-Erling Coïdan Smørgrav
3 * Copyright (c) 1999 Pierre Beyssac
4 * Copyright (c) 1993 Jan-Simon Pendry
6 * The Regents of the University of California. All rights reserved.
8 * This code is derived from software contributed to Berkeley by
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in the
18 * documentation and/or other materials provided with the distribution.
19 * 3. All advertising materials mentioning features or use of this software
20 * must display the following acknowledgement:
21 * This product includes software developed by the University of
22 * California, Berkeley and its contributors.
23 * 4. Neither the name of the University nor the names of its contributors
24 * may be used to endorse or promote products derived from this software
25 * without specific prior written permission.
27 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
28 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
29 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
30 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
31 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
32 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
33 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
34 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
35 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
36 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
39 * @(#)procfs_subr.c 8.6 (Berkeley) 5/14/95
41 * $FreeBSD: src/sys/i386/linux/linprocfs/linprocfs_subr.c,v 1.3.2.4 2001/06/25 19:46:47 pirzyk Exp $
42 * $DragonFly: src/sys/emulation/linux/i386/linprocfs/linprocfs_subr.c,v 1.23 2007/08/25 23:27:02 corecode Exp $
45 #include <sys/param.h>
46 #include <sys/systm.h>
48 #include <sys/vnode.h>
49 #include <sys/malloc.h>
50 #include <sys/mount.h>
51 #include "linprocfs.h"
54 #define PFSHMASK (PFSHSIZE - 1)
56 static struct pfsnode
*pfshead
[PFSHSIZE
];
57 static struct lwkt_token pfs_token
;
60 extern int procfs_domem (struct proc
*, struct lwp
*, struct pfsnode
*pfsp
, struct uio
*uio
);
63 * allocate a pfsnode/vnode pair. the vnode is
64 * referenced, but not locked.
66 * the pid, pfs_type, and mount point uniquely
67 * identify a pfsnode. the mount point is needed
68 * because someone might mount this filesystem
71 * all pfsnodes are maintained on a singly-linked
72 * list. new nodes are only allocated when they cannot
73 * be found on this list. entries on the list are
74 * removed when the vfs reclaim entry is called.
76 * a single lock is kept for the entire list. this is
77 * needed because the getnewvnode() function can block
78 * waiting for a vnode to become free, in which case there
79 * may be more than one process trying to get the same
80 * vnode. this lock is only taken if we are going to
81 * call getnewvnode, since the kernel itself is single-threaded.
83 * if an entry is found on the list, then call vget() to
84 * take a reference. this is done because there may be
85 * zero references to it and so it needs to removed from
86 * the vnode free list.
89 linprocfs_allocvp(struct mount
*mp
, struct vnode
**vpp
, long pid
,
98 lwkt_gettoken(&ilock
, &pfs_token
);
100 for (pfs
= pfshead
[pid
& PFSHMASK
]; pfs
; pfs
= pfs
->pfs_next
) {
102 if (pfs
->pfs_pid
== pid
&&
103 pfs
->pfs_type
== pfs_type
&&
105 if (vget(vp
, LK_EXCLUSIVE
|LK_SLEEPFAIL
))
108 lwkt_reltoken(&ilock
);
114 * otherwise lock the vp list while we call getnewvnode
115 * since that can block.
117 if (pfsvplock
& PROCFS_LOCKED
) {
118 pfsvplock
|= PROCFS_WANT
;
119 (void) tsleep((caddr_t
) &pfsvplock
, 0, "pfsavp", 0);
122 pfsvplock
|= PROCFS_LOCKED
;
125 * Do the MALLOC before the getnewvnode since doing so afterward
126 * might cause a bogus v_data pointer to get dereferenced
127 * elsewhere if MALLOC should block.
129 MALLOC(pfs
, struct pfsnode
*, sizeof(struct pfsnode
), M_TEMP
, M_WAITOK
);
131 error
= getnewvnode(VT_PROCFS
, mp
, vpp
, 0, 0);
141 pfs
->pfs_pid
= (pid_t
) pid
;
142 pfs
->pfs_type
= pfs_type
;
145 pfs
->pfs_lockowner
= NULL
;
146 pfs
->pfs_fileno
= PROCFS_FILENO(pid
, pfs_type
);
149 case Proot
: /* /proc = dr-xr-xr-x */
150 pfs
->pfs_mode
= (VREAD
|VEXEC
) |
154 vsetflags(vp
, VROOT
);
157 case Pself
: /* /proc/self = lr--r--r-- */
158 pfs
->pfs_mode
= (VREAD
) |
165 pfs
->pfs_mode
= (VREAD
|VEXEC
) |
172 pfs
->pfs_mode
= (VREAD
|VEXEC
) |
179 pfs
->pfs_mode
= (VREAD
|VWRITE
) |
194 pfs
->pfs_mode
= (VREAD
) |
201 panic("linprocfs_allocvp");
204 /* add to procfs vnode list */
205 for (pp
= &pfshead
[pid
& PFSHMASK
]; *pp
; pp
= &(*pp
)->pfs_next
)
209 vx_unlock(vp
); /* vnode ready to roll! */
212 pfsvplock
&= ~PROCFS_LOCKED
;
214 if (pfsvplock
& PROCFS_WANT
) {
215 pfsvplock
&= ~PROCFS_WANT
;
216 wakeup((caddr_t
) &pfsvplock
);
218 lwkt_reltoken(&ilock
);
224 linprocfs_freevp(struct vnode
*vp
)
226 struct pfsnode
**pfspp
;
227 struct pfsnode
*pfs
= VTOPFS(vp
);
230 lwkt_gettoken(&ilock
, &pfs_token
);
231 pfspp
= &pfshead
[pfs
->pfs_pid
& PFSHMASK
];
232 while (*pfspp
!= pfs
) {
233 KKASSERT(*pfspp
!= NULL
);
234 pfspp
= &(*pfspp
)->pfs_next
;
236 *pfspp
= pfs
->pfs_next
;
237 lwkt_reltoken(&ilock
);
238 FREE(vp
->v_data
, M_TEMP
);
244 linprocfs_rw(struct vop_read_args
*ap
)
246 struct vnode
*vp
= ap
->a_vp
;
247 struct uio
*uio
= ap
->a_uio
;
248 struct thread
*td
= uio
->uio_td
;
249 struct pfsnode
*pfs
= VTOPFS(vp
);
258 p
= PFIND(pfs
->pfs_pid
);
261 if (p
->p_pid
== 1 && securelevel
> 0 && uio
->uio_rw
== UIO_WRITE
)
263 lp
= FIRST_LWP_IN_PROC(p
);
266 while (pfs
->pfs_lockowner
) {
267 tsleep(&pfs
->pfs_lockowner
, 0, "pfslck", 0);
269 pfs
->pfs_lockowner
= curthread
;
271 switch (pfs
->pfs_type
) {
273 rtval
= procfs_domem(curp
, lp
, pfs
, uio
);
276 rtval
= linprocfs_doprocstat(curp
, p
, pfs
, uio
);
279 rtval
= linprocfs_doprocstatus(curp
, p
, pfs
, uio
);
282 rtval
= linprocfs_domeminfo(curp
, p
, pfs
, uio
);
285 rtval
= linprocfs_docpuinfo(curp
, p
, pfs
, uio
);
288 rtval
= linprocfs_dostat(curp
, p
, pfs
, uio
);
291 rtval
= linprocfs_douptime(curp
, p
, pfs
, uio
);
294 rtval
= linprocfs_doversion(curp
, p
, pfs
, uio
);
297 rtval
= linprocfs_doloadavg(curp
, p
, pfs
, uio
);
304 pfs
->pfs_lockowner
= NULL
;
305 wakeup(&pfs
->pfs_lockowner
);
311 * Get a string from userland into (buf). Strip a trailing
312 * nl character (to allow easy access from the shell).
313 * The buffer should be *buflenp + 1 chars long. vfs_getuserstr
314 * will automatically add a nul char at the end.
316 * Returns 0 on success or the following errors
318 * EINVAL: file offset is non-zero.
319 * EMSGSIZE: message is longer than kernel buffer
320 * EFAULT: user i/o buffer is not addressable
323 vfs_getuserstr(struct uio
*uio
, char *buf
, int *buflenp
)
328 if (uio
->uio_offset
!= 0)
333 /* must be able to read the whole string in one go */
334 if (xlen
< uio
->uio_resid
)
336 xlen
= uio
->uio_resid
;
338 if ((error
= uiomove(buf
, xlen
, uio
)) != 0)
341 /* allow multiple writes without seeks */
344 /* cleanup string and remove trailing newline */
347 if (xlen
> 0 && buf
[xlen
-1] == '\n')
355 vfs_findname(vfs_namemap_t
*nm
, char *buf
, int buflen
)
358 for (; nm
->nm_name
; nm
++)
359 if (bcmp(buf
, nm
->nm_name
, buflen
+1) == 0)
369 lwkt_token_init(&pfs_token
);
373 linprocfs_exit(struct thread
*td
)
380 KKASSERT(td
->td_proc
);
381 pid
= td
->td_proc
->p_pid
;
384 * Remove all the procfs vnodes associated with an exiting process.
386 lwkt_gettoken(&ilock
, &pfs_token
);
388 for (pfs
= pfshead
[pid
& PFSHMASK
]; pfs
; pfs
= pfs
->pfs_next
) {
389 if (pfs
->pfs_pid
== pid
) {
397 lwkt_reltoken(&ilock
);
398 lwkt_token_uninit(&pfs_token
);