Remove now unnecessary messing with PCI command register.
[dragonfly.git] / sys / vfs / procfs / procfs_subr.c
CommitLineData
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1/*
2 * Copyright (c) 1993 Jan-Simon Pendry
3 * Copyright (c) 1993
4 * The Regents of the University of California. All rights reserved.
5 *
6 * This code is derived from software contributed to Berkeley by
7 * Jan-Simon Pendry.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in the
16 * documentation and/or other materials provided with the distribution.
17 * 3. All advertising materials mentioning features or use of this software
18 * must display the following acknowledgement:
19 * This product includes software developed by the University of
20 * California, Berkeley and its contributors.
21 * 4. Neither the name of the University nor the names of its contributors
22 * may be used to endorse or promote products derived from this software
23 * without specific prior written permission.
24 *
25 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
27 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
28 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
29 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
30 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
31 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
32 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
33 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
34 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35 * SUCH DAMAGE.
36 *
37 * @(#)procfs_subr.c 8.6 (Berkeley) 5/14/95
38 *
39 * $FreeBSD: src/sys/miscfs/procfs/procfs_subr.c,v 1.26.2.3 2002/02/18 21:28:04 des Exp $
6ddb7618 40 * $DragonFly: src/sys/vfs/procfs/procfs_subr.c,v 1.12 2004/12/17 00:18:34 dillon Exp $
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41 */
42
43#include <sys/param.h>
44#include <sys/systm.h>
45#include <sys/sysctl.h>
46#include <sys/proc.h>
47#include <sys/mount.h>
48#include <sys/vnode.h>
49#include <sys/malloc.h>
50
1f2de5d4 51#include <vfs/procfs/procfs.h>
984263bc 52
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53#define PFS_HSIZE 256
54#define PFS_HMASK (PFS_HSIZE - 1)
55
56static struct pfsnode *pfshead[PFS_HSIZE];
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57static int pfsvplock;
58
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59#define PFSHASH(pid) &pfshead[(pid) & PFS_HMASK]
60
984263bc 61/*
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62 * Allocate a pfsnode/vnode pair. If no error occurs the returned vnode
63 * will be referenced and exclusively locked.
984263bc 64 *
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65 * The pid, pfs_type, and mount point uniquely identify a pfsnode.
66 * The mount point is needed because someone might mount this filesystem
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67 * twice.
68 *
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69 * All pfsnodes are maintained on a singly-linked list. new nodes are
70 * only allocated when they cannot be found on this list. entries on
71 * the list are removed when the vfs reclaim entry is called.
984263bc 72 *
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73 * A single lock is kept for the entire list. this is needed because the
74 * getnewvnode() function can block waiting for a vnode to become free,
75 * in which case there may be more than one process trying to get the same
76 * vnode. this lock is only taken if we are going to call getnewvnode,
77 * since the kernel itself is single-threaded.
984263bc 78 *
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79 * If an entry is found on the list, then call vget() to take a reference
80 * and obtain the lock. This will properly re-reference the vnode if it
81 * had gotten onto the free list.
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82 */
83int
ac424f9b 84procfs_allocvp(struct mount *mp, struct vnode **vpp, long pid, pfstype pfs_type)
984263bc 85{
dadab5e9 86 struct thread *td = curthread; /* XXX */
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87 struct pfsnode *pfs;
88 struct vnode *vp;
89 struct pfsnode **pp;
90 int error;
91
3446c007 92 pp = PFSHASH(pid);
984263bc 93loop:
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94 for (pfs = *pp; pfs; pfs = pfs->pfs_next) {
95 if (pfs->pfs_pid == pid && pfs->pfs_type == pfs_type &&
96 PFSTOV(pfs)->v_mount == mp) {
97 vp = PFSTOV(pfs);
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98 if (vget(vp, LK_EXCLUSIVE, td))
99 goto loop;
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100
101 /*
102 * Make sure the vnode is still in the cache after
103 * getting the interlock to avoid racing a free.
104 */
105 for (pfs = *pp; pfs; pfs = pfs->pfs_next) {
106 if (PFSTOV(pfs) == vp &&
107 pfs->pfs_pid == pid &&
108 pfs->pfs_type == pfs_type &&
109 PFSTOV(pfs)->v_mount == mp) {
110 break;
111 }
112 }
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113 if (pfs == NULL || PFSTOV(pfs) != vp) {
114 vput(vp);
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115 goto loop;
116
117 }
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118 *vpp = vp;
119 return (0);
120 }
121 }
122
123 /*
124 * otherwise lock the vp list while we call getnewvnode
125 * since that can block.
126 */
127 if (pfsvplock & PROCFS_LOCKED) {
128 pfsvplock |= PROCFS_WANT;
377d4740 129 (void) tsleep((caddr_t) &pfsvplock, 0, "pfsavp", 0);
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130 goto loop;
131 }
132 pfsvplock |= PROCFS_LOCKED;
133
134 /*
135 * Do the MALLOC before the getnewvnode since doing so afterward
136 * might cause a bogus v_data pointer to get dereferenced
137 * elsewhere if MALLOC should block.
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138 *
139 * XXX this may not matter anymore since getnewvnode now returns
140 * a VX locked vnode.
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141 */
142 MALLOC(pfs, struct pfsnode *, sizeof(struct pfsnode), M_TEMP, M_WAITOK);
143
6ddb7618 144 error = getnewvnode(VT_PROCFS, mp, vpp, 0, 0);
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145 if (error) {
146 free(pfs, M_TEMP);
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147 goto out;
148 }
149 vp = *vpp;
150
151 vp->v_data = pfs;
152
153 pfs->pfs_next = 0;
154 pfs->pfs_pid = (pid_t) pid;
155 pfs->pfs_type = pfs_type;
156 pfs->pfs_vnode = vp;
157 pfs->pfs_flags = 0;
158 pfs->pfs_lockowner = 0;
159 pfs->pfs_fileno = PROCFS_FILENO(pid, pfs_type);
160
161 switch (pfs_type) {
162 case Proot: /* /proc = dr-xr-xr-x */
163 pfs->pfs_mode = (VREAD|VEXEC) |
164 (VREAD|VEXEC) >> 3 |
165 (VREAD|VEXEC) >> 6;
166 vp->v_type = VDIR;
167 vp->v_flag = VROOT;
168 break;
169
170 case Pcurproc: /* /proc/curproc = lr--r--r-- */
171 pfs->pfs_mode = (VREAD) |
172 (VREAD >> 3) |
173 (VREAD >> 6);
174 vp->v_type = VLNK;
175 break;
176
177 case Pproc:
178 pfs->pfs_mode = (VREAD|VEXEC) |
179 (VREAD|VEXEC) >> 3 |
180 (VREAD|VEXEC) >> 6;
181 vp->v_type = VDIR;
182 break;
183
184 case Pfile:
185 pfs->pfs_mode = (VREAD|VEXEC) |
186 (VREAD|VEXEC) >> 3 |
187 (VREAD|VEXEC) >> 6;
188 vp->v_type = VLNK;
189 break;
190
191 case Pmem:
192 pfs->pfs_mode = (VREAD|VWRITE);
193 vp->v_type = VREG;
194 break;
195
196 case Pregs:
197 case Pfpregs:
198 case Pdbregs:
199 pfs->pfs_mode = (VREAD|VWRITE);
200 vp->v_type = VREG;
201 break;
202
203 case Pctl:
204 case Pnote:
205 case Pnotepg:
206 pfs->pfs_mode = (VWRITE);
207 vp->v_type = VREG;
208 break;
209
210 case Ptype:
211 case Pmap:
212 case Pstatus:
213 case Pcmdline:
214 case Prlimit:
215 pfs->pfs_mode = (VREAD) |
216 (VREAD >> 3) |
217 (VREAD >> 6);
218 vp->v_type = VREG;
219 break;
220
221 default:
222 panic("procfs_allocvp");
223 }
224
225 /* add to procfs vnode list */
3446c007 226 pfs->pfs_next = *pp;
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227 *pp = pfs;
228
229out:
230 pfsvplock &= ~PROCFS_LOCKED;
231
232 if (pfsvplock & PROCFS_WANT) {
233 pfsvplock &= ~PROCFS_WANT;
234 wakeup((caddr_t) &pfsvplock);
235 }
236
237 return (error);
238}
239
240int
ac424f9b 241procfs_freevp(struct vnode *vp)
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242{
243 struct pfsnode **pfspp;
3446c007 244 struct pfsnode *pfs;
984263bc 245
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246 pfs = VTOPFS(vp);
247 vp->v_data = NULL;
984263bc 248
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249 pfspp = PFSHASH(pfs->pfs_pid);
250 while (*pfspp != pfs && *pfspp)
251 pfspp = &(*pfspp)->pfs_next;
252 KKASSERT(*pfspp);
253 *pfspp = pfs->pfs_next;
254 pfs->pfs_next = NULL;
255 free(pfs, M_TEMP);
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256 return (0);
257}
258
259int
dadab5e9 260procfs_rw(struct vop_read_args *ap)
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261{
262 struct vnode *vp = ap->a_vp;
263 struct uio *uio = ap->a_uio;
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264 struct thread *curtd = uio->uio_td;
265 struct proc *curp;
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266 struct pfsnode *pfs = VTOPFS(vp);
267 struct proc *p;
268 int rtval;
269
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270 if (curtd == NULL)
271 return (EINVAL);
272 if ((curp = curtd->td_proc) == NULL) /* XXX */
273 return (EINVAL);
274
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275 p = PFIND(pfs->pfs_pid);
276 if (p == NULL)
277 return (EINVAL);
278 if (p->p_pid == 1 && securelevel > 0 && uio->uio_rw == UIO_WRITE)
279 return (EACCES);
280
281 while (pfs->pfs_lockowner) {
377d4740 282 tsleep(&pfs->pfs_lockowner, 0, "pfslck", 0);
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283 }
284 pfs->pfs_lockowner = curproc->p_pid;
285
286 switch (pfs->pfs_type) {
287 case Pnote:
288 case Pnotepg:
289 rtval = procfs_donote(curp, p, pfs, uio);
290 break;
291
292 case Pregs:
293 rtval = procfs_doregs(curp, p, pfs, uio);
294 break;
295
296 case Pfpregs:
297 rtval = procfs_dofpregs(curp, p, pfs, uio);
298 break;
299
300 case Pdbregs:
301 rtval = procfs_dodbregs(curp, p, pfs, uio);
302 break;
303
304 case Pctl:
305 rtval = procfs_doctl(curp, p, pfs, uio);
306 break;
307
308 case Pstatus:
309 rtval = procfs_dostatus(curp, p, pfs, uio);
310 break;
311
312 case Pmap:
313 rtval = procfs_domap(curp, p, pfs, uio);
314 break;
315
316 case Pmem:
317 rtval = procfs_domem(curp, p, pfs, uio);
318 break;
319
320 case Ptype:
321 rtval = procfs_dotype(curp, p, pfs, uio);
322 break;
323
324 case Pcmdline:
325 rtval = procfs_docmdline(curp, p, pfs, uio);
326 break;
327
328 case Prlimit:
329 rtval = procfs_dorlimit(curp, p, pfs, uio);
330 break;
331
332 default:
333 rtval = EOPNOTSUPP;
334 break;
335 }
336 pfs->pfs_lockowner = 0;
337 wakeup(&pfs->pfs_lockowner);
338 return rtval;
339}
340
341/*
342 * Get a string from userland into (buf). Strip a trailing
343 * nl character (to allow easy access from the shell).
344 * The buffer should be *buflenp + 1 chars long. vfs_getuserstr
345 * will automatically add a nul char at the end.
346 *
347 * Returns 0 on success or the following errors
348 *
349 * EINVAL: file offset is non-zero.
350 * EMSGSIZE: message is longer than kernel buffer
351 * EFAULT: user i/o buffer is not addressable
352 */
353int
ac424f9b 354vfs_getuserstr(struct uio *uio, char *buf, int *buflenp)
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355{
356 int xlen;
357 int error;
358
359 if (uio->uio_offset != 0)
360 return (EINVAL);
361
362 xlen = *buflenp;
363
364 /* must be able to read the whole string in one go */
365 if (xlen < uio->uio_resid)
366 return (EMSGSIZE);
367 xlen = uio->uio_resid;
368
369 if ((error = uiomove(buf, xlen, uio)) != 0)
370 return (error);
371
372 /* allow multiple writes without seeks */
373 uio->uio_offset = 0;
374
375 /* cleanup string and remove trailing newline */
376 buf[xlen] = '\0';
377 xlen = strlen(buf);
378 if (xlen > 0 && buf[xlen-1] == '\n')
379 buf[--xlen] = '\0';
380 *buflenp = xlen;
381
382 return (0);
383}
384
385vfs_namemap_t *
ac424f9b 386vfs_findname(vfs_namemap_t *nm, char *buf, int buflen)
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387{
388
389 for (; nm->nm_name; nm++)
390 if (bcmp(buf, nm->nm_name, buflen+1) == 0)
391 return (nm);
392
393 return (0);
394}
395
396void
dadab5e9 397procfs_exit(struct thread *td)
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398{
399 struct pfsnode *pfs;
5fd012e0 400 struct vnode *vp;
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401 pid_t pid;
402
403 KKASSERT(td->td_proc);
404 pid = td->td_proc->p_pid;
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405
406 /*
407 * The reason for this loop is not obvious -- basicly,
408 * procfs_freevp(), which is called via vgone() (eventually),
409 * removes the specified procfs node from the pfshead list.
410 * It does this by *pfsp = pfs->pfs_next, meaning that it
411 * overwrites the node. So when we do pfs = pfs->next, we
412 * end up skipping the node that replaces the one that was
413 * vgone'd. Since it may have been the last one on the list,
414 * it may also have been set to null -- but *our* pfs pointer,
415 * here, doesn't see this. So the loop starts from the beginning
416 * again.
417 *
418 * This is not a for() loop because the final event
419 * would be "pfs = pfs->pfs_next"; in the case where
420 * pfs is set to pfshead again, that would mean that
421 * pfshead is skipped over.
422 *
423 */
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424again:
425 pfs = *PFSHASH(pid);
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426 while (pfs) {
427 if (pfs->pfs_pid == pid) {
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428 vp = PFSTOV(pfs);
429 if (vx_lock(vp) == 0) {
430 vgone(vp);
431 vx_unlock(vp);
432 }
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433 goto again;
434 }
435 pfs = pfs->pfs_next;
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436 }
437}
3446c007 438