Register keyword removal
[dragonfly.git] / sys / kern / kern_memio.c
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1/*-
2 * Copyright (c) 1988 University of Utah.
3 * Copyright (c) 1982, 1986, 1990 The Regents of the University of California.
4 * All rights reserved.
5 *
6 * This code is derived from software contributed to Berkeley by
7 * the Systems Programming Group of the University of Utah Computer
8 * Science Department, and code derived from software contributed to
9 * Berkeley by William Jolitz.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
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.
26 *
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
37 * SUCH DAMAGE.
38 *
39 * from: Utah $Hdr: mem.c 1.13 89/10/08$
40 * from: @(#)mem.c 7.2 (Berkeley) 5/9/91
41 * $FreeBSD: src/sys/i386/i386/mem.c,v 1.79.2.9 2003/01/04 22:58:01 njl Exp $
fabb8ceb 42 * $DragonFly: src/sys/kern/kern_memio.c,v 1.7 2003/07/21 05:50:39 dillon Exp $
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43 */
44
45/*
46 * Memory special file
47 */
48
49#include <sys/param.h>
50#include <sys/systm.h>
51#include <sys/buf.h>
52#include <sys/conf.h>
53#include <sys/fcntl.h>
54#include <sys/filio.h>
55#include <sys/ioccom.h>
56#include <sys/kernel.h>
57#include <sys/malloc.h>
58#include <sys/memrange.h>
59#include <sys/proc.h>
60#include <sys/random.h>
61#include <sys/signalvar.h>
62#include <sys/uio.h>
63#include <sys/vnode.h>
64
65#include <machine/frame.h>
66#include <machine/psl.h>
67#include <machine/specialreg.h>
68#include <i386/isa/intr_machdep.h>
69
70#include <vm/vm.h>
71#include <vm/pmap.h>
72#include <vm/vm_extern.h>
73
74
75static d_open_t mmopen;
76static d_close_t mmclose;
77static d_read_t mmrw;
78static d_ioctl_t mmioctl;
79static d_mmap_t memmmap;
80static d_poll_t mmpoll;
81
82#define CDEV_MAJOR 2
83static struct cdevsw mem_cdevsw = {
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84 /* name */ "mem",
85 /* maj */ CDEV_MAJOR,
86 /* flags */ D_MEM,
87 /* port */ NULL,
88 /* autoq */ 0,
89
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90 /* open */ mmopen,
91 /* close */ mmclose,
92 /* read */ mmrw,
93 /* write */ mmrw,
94 /* ioctl */ mmioctl,
95 /* poll */ mmpoll,
96 /* mmap */ memmmap,
97 /* strategy */ nostrategy,
984263bc 98 /* dump */ nodump,
fabb8ceb 99 /* psize */ nopsize
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100};
101
7e071e7a 102static int rand_bolt;
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103static caddr_t zbuf;
104
105MALLOC_DEFINE(M_MEMDESC, "memdesc", "memory range descriptors");
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106static int mem_ioctl __P((dev_t, u_long, caddr_t, int, struct thread *));
107static int random_ioctl __P((dev_t, u_long, caddr_t, int, struct thread *));
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108
109struct mem_range_softc mem_range_softc;
110
111
112static int
41c20dac 113mmclose(dev_t dev, int flags, int fmt, struct thread *td)
984263bc 114{
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115 struct proc *p = td->td_proc;
116
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117 switch (minor(dev)) {
118 case 14:
119 p->p_md.md_regs->tf_eflags &= ~PSL_IOPL;
120 break;
121 default:
122 break;
123 }
124 return (0);
125}
126
127static int
41c20dac 128mmopen(dev_t dev, int flags, int fmt, struct thread *td)
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129{
130 int error;
41c20dac 131 struct proc *p = td->td_proc;
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132
133 switch (minor(dev)) {
134 case 0:
135 case 1:
136 if ((flags & FWRITE) && securelevel > 0)
137 return (EPERM);
138 break;
139 case 14:
dadab5e9 140 error = suser(td);
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141 if (error != 0)
142 return (error);
143 if (securelevel > 0)
144 return (EPERM);
145 p->p_md.md_regs->tf_eflags |= PSL_IOPL;
146 break;
147 default:
148 break;
149 }
150 return (0);
151}
152
153static int
154mmrw(dev, uio, flags)
155 dev_t dev;
156 struct uio *uio;
157 int flags;
158{
159 register int o;
160 register u_int c, v;
161 u_int poolsize;
162 register struct iovec *iov;
163 int error = 0;
164 caddr_t buf = NULL;
165
166 while (uio->uio_resid > 0 && error == 0) {
167 iov = uio->uio_iov;
168 if (iov->iov_len == 0) {
169 uio->uio_iov++;
170 uio->uio_iovcnt--;
171 if (uio->uio_iovcnt < 0)
172 panic("mmrw");
173 continue;
174 }
175 switch (minor(dev)) {
176
177/* minor device 0 is physical memory */
178 case 0:
179 v = uio->uio_offset;
180 v &= ~PAGE_MASK;
181 pmap_kenter((vm_offset_t)ptvmmap, v);
182 o = (int)uio->uio_offset & PAGE_MASK;
183 c = (u_int)(PAGE_SIZE - ((int)iov->iov_base & PAGE_MASK));
184 c = min(c, (u_int)(PAGE_SIZE - o));
185 c = min(c, (u_int)iov->iov_len);
186 error = uiomove((caddr_t)&ptvmmap[o], (int)c, uio);
187 pmap_kremove((vm_offset_t)ptvmmap);
188 continue;
189
190/* minor device 1 is kernel memory */
191 case 1: {
192 vm_offset_t addr, eaddr;
193 c = iov->iov_len;
194
195 /*
196 * Make sure that all of the pages are currently resident so
197 * that we don't create any zero-fill pages.
198 */
199 addr = trunc_page(uio->uio_offset);
200 eaddr = round_page(uio->uio_offset + c);
201
202 if (addr < (vm_offset_t)VADDR(PTDPTDI, 0))
203 return EFAULT;
204 if (eaddr >= (vm_offset_t)VADDR(APTDPTDI, 0))
205 return EFAULT;
206 for (; addr < eaddr; addr += PAGE_SIZE)
207 if (pmap_extract(kernel_pmap, addr) == 0)
208 return EFAULT;
209
210 if (!kernacc((caddr_t)(int)uio->uio_offset, c,
211 uio->uio_rw == UIO_READ ?
212 VM_PROT_READ : VM_PROT_WRITE))
213 return (EFAULT);
214 error = uiomove((caddr_t)(int)uio->uio_offset, (int)c, uio);
215 continue;
216 }
217
218/* minor device 2 is EOF/RATHOLE */
219 case 2:
220 if (uio->uio_rw == UIO_READ)
221 return (0);
222 c = iov->iov_len;
223 break;
224
225/* minor device 3 (/dev/random) is source of filth on read, rathole on write */
226 case 3:
227 if (uio->uio_rw == UIO_WRITE) {
228 c = iov->iov_len;
229 break;
230 }
231 if (buf == NULL)
232 buf = (caddr_t)
233 malloc(PAGE_SIZE, M_TEMP, M_WAITOK);
234 c = min(iov->iov_len, PAGE_SIZE);
235 poolsize = read_random(buf, c);
236 if (poolsize == 0) {
237 if (buf)
238 free(buf, M_TEMP);
239 if ((flags & IO_NDELAY) != 0)
240 return (EWOULDBLOCK);
241 return (0);
242 }
243 c = min(c, poolsize);
244 error = uiomove(buf, (int)c, uio);
245 continue;
246
247/* minor device 4 (/dev/urandom) is source of muck on read, rathole on write */
248 case 4:
249 if (uio->uio_rw == UIO_WRITE) {
250 c = iov->iov_len;
251 break;
252 }
253 if (CURSIG(curproc) != 0) {
254 /*
255 * Use tsleep() to get the error code right.
256 * It should return immediately.
257 */
377d4740 258 error = tsleep(&rand_bolt, PCATCH, "urand", 1);
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259 if (error != 0 && error != EWOULDBLOCK)
260 continue;
261 }
262 if (buf == NULL)
263 buf = (caddr_t)
264 malloc(PAGE_SIZE, M_TEMP, M_WAITOK);
265 c = min(iov->iov_len, PAGE_SIZE);
266 poolsize = read_random_unlimited(buf, c);
267 c = min(c, poolsize);
268 error = uiomove(buf, (int)c, uio);
269 continue;
270
271/* minor device 12 (/dev/zero) is source of nulls on read, rathole on write */
272 case 12:
273 if (uio->uio_rw == UIO_WRITE) {
274 c = iov->iov_len;
275 break;
276 }
277 if (zbuf == NULL) {
278 zbuf = (caddr_t)
279 malloc(PAGE_SIZE, M_TEMP, M_WAITOK);
280 bzero(zbuf, PAGE_SIZE);
281 }
282 c = min(iov->iov_len, PAGE_SIZE);
283 error = uiomove(zbuf, (int)c, uio);
284 continue;
285
286 default:
287 return (ENODEV);
288 }
289 if (error)
290 break;
291 iov->iov_base += c;
292 iov->iov_len -= c;
293 uio->uio_offset += c;
294 uio->uio_resid -= c;
295 }
296 if (buf)
297 free(buf, M_TEMP);
298 return (error);
299}
300
301
302
303
304/*******************************************************\
305* allow user processes to MMAP some memory sections *
306* instead of going through read/write *
307\*******************************************************/
308static int
309memmmap(dev_t dev, vm_offset_t offset, int nprot)
310{
311 switch (minor(dev))
312 {
313
314/* minor device 0 is physical memory */
315 case 0:
316 return i386_btop(offset);
317
318/* minor device 1 is kernel memory */
319 case 1:
320 return i386_btop(vtophys(offset));
321
322 default:
323 return -1;
324 }
325}
326
327static int
41c20dac 328mmioctl(dev_t dev, u_long cmd, caddr_t data, int flags, struct thread *td)
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329{
330
331 switch (minor(dev)) {
332 case 0:
41c20dac 333 return mem_ioctl(dev, cmd, data, flags, td);
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334 case 3:
335 case 4:
41c20dac 336 return random_ioctl(dev, cmd, data, flags, td);
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337 }
338 return (ENODEV);
339}
340
341/*
342 * Operations for changing memory attributes.
343 *
344 * This is basically just an ioctl shim for mem_range_attr_get
345 * and mem_range_attr_set.
346 */
347static int
41c20dac 348mem_ioctl(dev_t dev, u_long cmd, caddr_t data, int flags, struct thread *td)
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349{
350 int nd, error = 0;
351 struct mem_range_op *mo = (struct mem_range_op *)data;
352 struct mem_range_desc *md;
353
354 /* is this for us? */
355 if ((cmd != MEMRANGE_GET) &&
356 (cmd != MEMRANGE_SET))
357 return (ENOTTY);
358
359 /* any chance we can handle this? */
360 if (mem_range_softc.mr_op == NULL)
361 return (EOPNOTSUPP);
362
363 /* do we have any descriptors? */
364 if (mem_range_softc.mr_ndesc == 0)
365 return (ENXIO);
366
367 switch (cmd) {
368 case MEMRANGE_GET:
369 nd = imin(mo->mo_arg[0], mem_range_softc.mr_ndesc);
370 if (nd > 0) {
371 md = (struct mem_range_desc *)
372 malloc(nd * sizeof(struct mem_range_desc),
373 M_MEMDESC, M_WAITOK);
374 error = mem_range_attr_get(md, &nd);
375 if (!error)
376 error = copyout(md, mo->mo_desc,
377 nd * sizeof(struct mem_range_desc));
378 free(md, M_MEMDESC);
379 } else {
380 nd = mem_range_softc.mr_ndesc;
381 }
382 mo->mo_arg[0] = nd;
383 break;
384
385 case MEMRANGE_SET:
386 md = (struct mem_range_desc *)malloc(sizeof(struct mem_range_desc),
387 M_MEMDESC, M_WAITOK);
388 error = copyin(mo->mo_desc, md, sizeof(struct mem_range_desc));
389 /* clamp description string */
390 md->mr_owner[sizeof(md->mr_owner) - 1] = 0;
391 if (error == 0)
392 error = mem_range_attr_set(md, &mo->mo_arg[0]);
393 free(md, M_MEMDESC);
394 break;
395 }
396 return (error);
397}
398
399/*
400 * Implementation-neutral, kernel-callable functions for manipulating
401 * memory range attributes.
402 */
403int
404mem_range_attr_get(mrd, arg)
405 struct mem_range_desc *mrd;
406 int *arg;
407{
408 /* can we handle this? */
409 if (mem_range_softc.mr_op == NULL)
410 return (EOPNOTSUPP);
411
412 if (*arg == 0) {
413 *arg = mem_range_softc.mr_ndesc;
414 } else {
415 bcopy(mem_range_softc.mr_desc, mrd, (*arg) * sizeof(struct mem_range_desc));
416 }
417 return (0);
418}
419
420int
421mem_range_attr_set(mrd, arg)
422 struct mem_range_desc *mrd;
423 int *arg;
424{
425 /* can we handle this? */
426 if (mem_range_softc.mr_op == NULL)
427 return (EOPNOTSUPP);
428
429 return (mem_range_softc.mr_op->set(&mem_range_softc, mrd, arg));
430}
431
432#ifdef SMP
433void
434mem_range_AP_init(void)
435{
436 if (mem_range_softc.mr_op && mem_range_softc.mr_op->initAP)
437 return (mem_range_softc.mr_op->initAP(&mem_range_softc));
438}
439#endif
440
441static int
41c20dac 442random_ioctl(dev_t dev, u_long cmd, caddr_t data, int flags, struct thread *td)
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443{
444 static intrmask_t interrupt_allowed;
445 intrmask_t interrupt_mask;
446 int error, intr;
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447
448 /*
449 * We're the random or urandom device. The only ioctls are for
450 * selecting and inspecting which interrupts are used in the muck
451 * gathering business and the fcntl() stuff.
452 */
453 if (cmd != MEM_SETIRQ && cmd != MEM_CLEARIRQ && cmd != MEM_RETURNIRQ
454 && cmd != FIONBIO && cmd != FIOASYNC)
455 return (ENOTTY);
456
457 /*
458 * XXX the data is 16-bit due to a historical botch, so we use
459 * magic 16's instead of ICU_LEN and can't support 24 interrupts
460 * under SMP.
461 * Even inspecting the state is privileged, since it gives a hint
462 * about how easily the randomness might be guessed.
463 */
464 intr = *(int16_t *)data;
465 interrupt_mask = 1 << intr;
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466 switch (cmd) {
467 /* Really handled in upper layer */
468 case FIOASYNC:
469 case FIONBIO:
470 break;
471 case MEM_SETIRQ:
dadab5e9 472 error = suser(td);
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473 if (error != 0)
474 return (error);
475 if (intr < 0 || intr >= 16)
476 return (EINVAL);
477 if (interrupt_allowed & interrupt_mask)
478 break;
479 interrupt_allowed |= interrupt_mask;
7e071e7a 480 register_randintr(intr);
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481 break;
482 case MEM_CLEARIRQ:
dadab5e9 483 error = suser(td);
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484 if (error != 0)
485 return (error);
486 if (intr < 0 || intr >= 16)
487 return (EINVAL);
488 if (!(interrupt_allowed & interrupt_mask))
489 break;
490 interrupt_allowed &= ~interrupt_mask;
7e071e7a 491 unregister_randintr(intr);
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492 break;
493 case MEM_RETURNIRQ:
dadab5e9 494 error = suser(td);
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495 if (error != 0)
496 return (error);
497 *(u_int16_t *)data = interrupt_allowed;
498 break;
499 }
500 return (0);
501}
502
503int
41c20dac 504mmpoll(dev_t dev, int events, struct thread *td)
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505{
506 switch (minor(dev)) {
507 case 3: /* /dev/random */
41c20dac 508 return random_poll(dev, events, td);
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509 case 4: /* /dev/urandom */
510 default:
41c20dac 511 return seltrue(dev, events, td);
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512 }
513}
514
515int
516iszerodev(dev)
517 dev_t dev;
518{
519 return ((major(dev) == mem_cdevsw.d_maj)
520 && minor(dev) == 12);
521}
522
523static void
524mem_drvinit(void *unused)
525{
526
527 /* Initialise memory range handling */
528 if (mem_range_softc.mr_op != NULL)
529 mem_range_softc.mr_op->init(&mem_range_softc);
530
531 make_dev(&mem_cdevsw, 0, UID_ROOT, GID_KMEM, 0640, "mem");
532 make_dev(&mem_cdevsw, 1, UID_ROOT, GID_KMEM, 0640, "kmem");
533 make_dev(&mem_cdevsw, 2, UID_ROOT, GID_WHEEL, 0666, "null");
534 make_dev(&mem_cdevsw, 3, UID_ROOT, GID_WHEEL, 0644, "random");
535 make_dev(&mem_cdevsw, 4, UID_ROOT, GID_WHEEL, 0644, "urandom");
536 make_dev(&mem_cdevsw, 12, UID_ROOT, GID_WHEEL, 0666, "zero");
537 make_dev(&mem_cdevsw, 14, UID_ROOT, GID_WHEEL, 0600, "io");
538}
539
540SYSINIT(memdev,SI_SUB_DRIVERS,SI_ORDER_MIDDLE+CDEV_MAJOR,mem_drvinit,NULL)
541