2 * Copyright (c) 1988 University of Utah.
3 * Copyright (c) 1982, 1986, 1990 The Regents of the University of California.
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.
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 * 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 $
42 * $DragonFly: src/sys/kern/kern_memio.c,v 1.7 2003/07/21 05:50:39 dillon Exp $
49 #include <sys/param.h>
50 #include <sys/systm.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>
60 #include <sys/random.h>
61 #include <sys/signalvar.h>
63 #include <sys/vnode.h>
65 #include <machine/frame.h>
66 #include <machine/psl.h>
67 #include <machine/specialreg.h>
68 #include <i386/isa/intr_machdep.h>
72 #include <vm/vm_extern.h>
75 static d_open_t mmopen;
76 static d_close_t mmclose;
78 static d_ioctl_t mmioctl;
79 static d_mmap_t memmmap;
80 static d_poll_t mmpoll;
83 static struct cdevsw mem_cdevsw = {
97 /* strategy */ nostrategy,
102 static int rand_bolt;
105 MALLOC_DEFINE(M_MEMDESC, "memdesc", "memory range descriptors");
106 static int mem_ioctl __P((dev_t, u_long, caddr_t, int, struct thread *));
107 static int random_ioctl __P((dev_t, u_long, caddr_t, int, struct thread *));
109 struct mem_range_softc mem_range_softc;
113 mmclose(dev_t dev, int flags, int fmt, struct thread *td)
115 struct proc *p = td->td_proc;
117 switch (minor(dev)) {
119 p->p_md.md_regs->tf_eflags &= ~PSL_IOPL;
128 mmopen(dev_t dev, int flags, int fmt, struct thread *td)
131 struct proc *p = td->td_proc;
133 switch (minor(dev)) {
136 if ((flags & FWRITE) && securelevel > 0)
145 p->p_md.md_regs->tf_eflags |= PSL_IOPL;
154 mmrw(dev, uio, flags)
162 register struct iovec *iov;
166 while (uio->uio_resid > 0 && error == 0) {
168 if (iov->iov_len == 0) {
171 if (uio->uio_iovcnt < 0)
175 switch (minor(dev)) {
177 /* minor device 0 is physical memory */
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);
190 /* minor device 1 is kernel memory */
192 vm_offset_t addr, eaddr;
196 * Make sure that all of the pages are currently resident so
197 * that we don't create any zero-fill pages.
199 addr = trunc_page(uio->uio_offset);
200 eaddr = round_page(uio->uio_offset + c);
202 if (addr < (vm_offset_t)VADDR(PTDPTDI, 0))
204 if (eaddr >= (vm_offset_t)VADDR(APTDPTDI, 0))
206 for (; addr < eaddr; addr += PAGE_SIZE)
207 if (pmap_extract(kernel_pmap, addr) == 0)
210 if (!kernacc((caddr_t)(int)uio->uio_offset, c,
211 uio->uio_rw == UIO_READ ?
212 VM_PROT_READ : VM_PROT_WRITE))
214 error = uiomove((caddr_t)(int)uio->uio_offset, (int)c, uio);
218 /* minor device 2 is EOF/RATHOLE */
220 if (uio->uio_rw == UIO_READ)
225 /* minor device 3 (/dev/random) is source of filth on read, rathole on write */
227 if (uio->uio_rw == UIO_WRITE) {
233 malloc(PAGE_SIZE, M_TEMP, M_WAITOK);
234 c = min(iov->iov_len, PAGE_SIZE);
235 poolsize = read_random(buf, c);
239 if ((flags & IO_NDELAY) != 0)
240 return (EWOULDBLOCK);
243 c = min(c, poolsize);
244 error = uiomove(buf, (int)c, uio);
247 /* minor device 4 (/dev/urandom) is source of muck on read, rathole on write */
249 if (uio->uio_rw == UIO_WRITE) {
253 if (CURSIG(curproc) != 0) {
255 * Use tsleep() to get the error code right.
256 * It should return immediately.
258 error = tsleep(&rand_bolt, PCATCH, "urand", 1);
259 if (error != 0 && error != EWOULDBLOCK)
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);
271 /* minor device 12 (/dev/zero) is source of nulls on read, rathole on write */
273 if (uio->uio_rw == UIO_WRITE) {
279 malloc(PAGE_SIZE, M_TEMP, M_WAITOK);
280 bzero(zbuf, PAGE_SIZE);
282 c = min(iov->iov_len, PAGE_SIZE);
283 error = uiomove(zbuf, (int)c, uio);
293 uio->uio_offset += c;
304 /*******************************************************\
305 * allow user processes to MMAP some memory sections *
306 * instead of going through read/write *
307 \*******************************************************/
309 memmmap(dev_t dev, vm_offset_t offset, int nprot)
314 /* minor device 0 is physical memory */
316 return i386_btop(offset);
318 /* minor device 1 is kernel memory */
320 return i386_btop(vtophys(offset));
328 mmioctl(dev_t dev, u_long cmd, caddr_t data, int flags, struct thread *td)
331 switch (minor(dev)) {
333 return mem_ioctl(dev, cmd, data, flags, td);
336 return random_ioctl(dev, cmd, data, flags, td);
342 * Operations for changing memory attributes.
344 * This is basically just an ioctl shim for mem_range_attr_get
345 * and mem_range_attr_set.
348 mem_ioctl(dev_t dev, u_long cmd, caddr_t data, int flags, struct thread *td)
351 struct mem_range_op *mo = (struct mem_range_op *)data;
352 struct mem_range_desc *md;
354 /* is this for us? */
355 if ((cmd != MEMRANGE_GET) &&
356 (cmd != MEMRANGE_SET))
359 /* any chance we can handle this? */
360 if (mem_range_softc.mr_op == NULL)
363 /* do we have any descriptors? */
364 if (mem_range_softc.mr_ndesc == 0)
369 nd = imin(mo->mo_arg[0], mem_range_softc.mr_ndesc);
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);
376 error = copyout(md, mo->mo_desc,
377 nd * sizeof(struct mem_range_desc));
380 nd = mem_range_softc.mr_ndesc;
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;
392 error = mem_range_attr_set(md, &mo->mo_arg[0]);
400 * Implementation-neutral, kernel-callable functions for manipulating
401 * memory range attributes.
404 mem_range_attr_get(mrd, arg)
405 struct mem_range_desc *mrd;
408 /* can we handle this? */
409 if (mem_range_softc.mr_op == NULL)
413 *arg = mem_range_softc.mr_ndesc;
415 bcopy(mem_range_softc.mr_desc, mrd, (*arg) * sizeof(struct mem_range_desc));
421 mem_range_attr_set(mrd, arg)
422 struct mem_range_desc *mrd;
425 /* can we handle this? */
426 if (mem_range_softc.mr_op == NULL)
429 return (mem_range_softc.mr_op->set(&mem_range_softc, mrd, arg));
434 mem_range_AP_init(void)
436 if (mem_range_softc.mr_op && mem_range_softc.mr_op->initAP)
437 return (mem_range_softc.mr_op->initAP(&mem_range_softc));
442 random_ioctl(dev_t dev, u_long cmd, caddr_t data, int flags, struct thread *td)
444 static intrmask_t interrupt_allowed;
445 intrmask_t interrupt_mask;
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.
453 if (cmd != MEM_SETIRQ && cmd != MEM_CLEARIRQ && cmd != MEM_RETURNIRQ
454 && cmd != FIONBIO && cmd != FIOASYNC)
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
461 * Even inspecting the state is privileged, since it gives a hint
462 * about how easily the randomness might be guessed.
464 intr = *(int16_t *)data;
465 interrupt_mask = 1 << intr;
467 /* Really handled in upper layer */
475 if (intr < 0 || intr >= 16)
477 if (interrupt_allowed & interrupt_mask)
479 interrupt_allowed |= interrupt_mask;
480 register_randintr(intr);
486 if (intr < 0 || intr >= 16)
488 if (!(interrupt_allowed & interrupt_mask))
490 interrupt_allowed &= ~interrupt_mask;
491 unregister_randintr(intr);
497 *(u_int16_t *)data = interrupt_allowed;
504 mmpoll(dev_t dev, int events, struct thread *td)
506 switch (minor(dev)) {
507 case 3: /* /dev/random */
508 return random_poll(dev, events, td);
509 case 4: /* /dev/urandom */
511 return seltrue(dev, events, td);
519 return ((major(dev) == mem_cdevsw.d_maj)
520 && minor(dev) == 12);
524 mem_drvinit(void *unused)
527 /* Initialise memory range handling */
528 if (mem_range_softc.mr_op != NULL)
529 mem_range_softc.mr_op->init(&mem_range_softc);
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");
540 SYSINIT(memdev,SI_SUB_DRIVERS,SI_ORDER_MIDDLE+CDEV_MAJOR,mem_drvinit,NULL)