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 1.6 2003/07/19 21:14:33 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 = {
91 /* strategy */ nostrategy,
100 static int rand_bolt;
103 MALLOC_DEFINE(M_MEMDESC, "memdesc", "memory range descriptors");
104 static int mem_ioctl __P((dev_t, u_long, caddr_t, int, struct thread *));
105 static int random_ioctl __P((dev_t, u_long, caddr_t, int, struct thread *));
107 struct mem_range_softc mem_range_softc;
111 mmclose(dev_t dev, int flags, int fmt, struct thread *td)
113 struct proc *p = td->td_proc;
115 switch (minor(dev)) {
117 p->p_md.md_regs->tf_eflags &= ~PSL_IOPL;
126 mmopen(dev_t dev, int flags, int fmt, struct thread *td)
129 struct proc *p = td->td_proc;
131 switch (minor(dev)) {
134 if ((flags & FWRITE) && securelevel > 0)
143 p->p_md.md_regs->tf_eflags |= PSL_IOPL;
152 mmrw(dev, uio, flags)
160 register struct iovec *iov;
164 while (uio->uio_resid > 0 && error == 0) {
166 if (iov->iov_len == 0) {
169 if (uio->uio_iovcnt < 0)
173 switch (minor(dev)) {
175 /* minor device 0 is physical memory */
179 pmap_kenter((vm_offset_t)ptvmmap, v);
180 o = (int)uio->uio_offset & PAGE_MASK;
181 c = (u_int)(PAGE_SIZE - ((int)iov->iov_base & PAGE_MASK));
182 c = min(c, (u_int)(PAGE_SIZE - o));
183 c = min(c, (u_int)iov->iov_len);
184 error = uiomove((caddr_t)&ptvmmap[o], (int)c, uio);
185 pmap_kremove((vm_offset_t)ptvmmap);
188 /* minor device 1 is kernel memory */
190 vm_offset_t addr, eaddr;
194 * Make sure that all of the pages are currently resident so
195 * that we don't create any zero-fill pages.
197 addr = trunc_page(uio->uio_offset);
198 eaddr = round_page(uio->uio_offset + c);
200 if (addr < (vm_offset_t)VADDR(PTDPTDI, 0))
202 if (eaddr >= (vm_offset_t)VADDR(APTDPTDI, 0))
204 for (; addr < eaddr; addr += PAGE_SIZE)
205 if (pmap_extract(kernel_pmap, addr) == 0)
208 if (!kernacc((caddr_t)(int)uio->uio_offset, c,
209 uio->uio_rw == UIO_READ ?
210 VM_PROT_READ : VM_PROT_WRITE))
212 error = uiomove((caddr_t)(int)uio->uio_offset, (int)c, uio);
216 /* minor device 2 is EOF/RATHOLE */
218 if (uio->uio_rw == UIO_READ)
223 /* minor device 3 (/dev/random) is source of filth on read, rathole on write */
225 if (uio->uio_rw == UIO_WRITE) {
231 malloc(PAGE_SIZE, M_TEMP, M_WAITOK);
232 c = min(iov->iov_len, PAGE_SIZE);
233 poolsize = read_random(buf, c);
237 if ((flags & IO_NDELAY) != 0)
238 return (EWOULDBLOCK);
241 c = min(c, poolsize);
242 error = uiomove(buf, (int)c, uio);
245 /* minor device 4 (/dev/urandom) is source of muck on read, rathole on write */
247 if (uio->uio_rw == UIO_WRITE) {
251 if (CURSIG(curproc) != 0) {
253 * Use tsleep() to get the error code right.
254 * It should return immediately.
256 error = tsleep(&rand_bolt, PCATCH, "urand", 1);
257 if (error != 0 && error != EWOULDBLOCK)
262 malloc(PAGE_SIZE, M_TEMP, M_WAITOK);
263 c = min(iov->iov_len, PAGE_SIZE);
264 poolsize = read_random_unlimited(buf, c);
265 c = min(c, poolsize);
266 error = uiomove(buf, (int)c, uio);
269 /* minor device 12 (/dev/zero) is source of nulls on read, rathole on write */
271 if (uio->uio_rw == UIO_WRITE) {
277 malloc(PAGE_SIZE, M_TEMP, M_WAITOK);
278 bzero(zbuf, PAGE_SIZE);
280 c = min(iov->iov_len, PAGE_SIZE);
281 error = uiomove(zbuf, (int)c, uio);
291 uio->uio_offset += c;
302 /*******************************************************\
303 * allow user processes to MMAP some memory sections *
304 * instead of going through read/write *
305 \*******************************************************/
307 memmmap(dev_t dev, vm_offset_t offset, int nprot)
312 /* minor device 0 is physical memory */
314 return i386_btop(offset);
316 /* minor device 1 is kernel memory */
318 return i386_btop(vtophys(offset));
326 mmioctl(dev_t dev, u_long cmd, caddr_t data, int flags, struct thread *td)
329 switch (minor(dev)) {
331 return mem_ioctl(dev, cmd, data, flags, td);
334 return random_ioctl(dev, cmd, data, flags, td);
340 * Operations for changing memory attributes.
342 * This is basically just an ioctl shim for mem_range_attr_get
343 * and mem_range_attr_set.
346 mem_ioctl(dev_t dev, u_long cmd, caddr_t data, int flags, struct thread *td)
349 struct mem_range_op *mo = (struct mem_range_op *)data;
350 struct mem_range_desc *md;
352 /* is this for us? */
353 if ((cmd != MEMRANGE_GET) &&
354 (cmd != MEMRANGE_SET))
357 /* any chance we can handle this? */
358 if (mem_range_softc.mr_op == NULL)
361 /* do we have any descriptors? */
362 if (mem_range_softc.mr_ndesc == 0)
367 nd = imin(mo->mo_arg[0], mem_range_softc.mr_ndesc);
369 md = (struct mem_range_desc *)
370 malloc(nd * sizeof(struct mem_range_desc),
371 M_MEMDESC, M_WAITOK);
372 error = mem_range_attr_get(md, &nd);
374 error = copyout(md, mo->mo_desc,
375 nd * sizeof(struct mem_range_desc));
378 nd = mem_range_softc.mr_ndesc;
384 md = (struct mem_range_desc *)malloc(sizeof(struct mem_range_desc),
385 M_MEMDESC, M_WAITOK);
386 error = copyin(mo->mo_desc, md, sizeof(struct mem_range_desc));
387 /* clamp description string */
388 md->mr_owner[sizeof(md->mr_owner) - 1] = 0;
390 error = mem_range_attr_set(md, &mo->mo_arg[0]);
398 * Implementation-neutral, kernel-callable functions for manipulating
399 * memory range attributes.
402 mem_range_attr_get(mrd, arg)
403 struct mem_range_desc *mrd;
406 /* can we handle this? */
407 if (mem_range_softc.mr_op == NULL)
411 *arg = mem_range_softc.mr_ndesc;
413 bcopy(mem_range_softc.mr_desc, mrd, (*arg) * sizeof(struct mem_range_desc));
419 mem_range_attr_set(mrd, arg)
420 struct mem_range_desc *mrd;
423 /* can we handle this? */
424 if (mem_range_softc.mr_op == NULL)
427 return (mem_range_softc.mr_op->set(&mem_range_softc, mrd, arg));
432 mem_range_AP_init(void)
434 if (mem_range_softc.mr_op && mem_range_softc.mr_op->initAP)
435 return (mem_range_softc.mr_op->initAP(&mem_range_softc));
440 random_ioctl(dev_t dev, u_long cmd, caddr_t data, int flags, struct thread *td)
442 static intrmask_t interrupt_allowed;
443 intrmask_t interrupt_mask;
447 * We're the random or urandom device. The only ioctls are for
448 * selecting and inspecting which interrupts are used in the muck
449 * gathering business and the fcntl() stuff.
451 if (cmd != MEM_SETIRQ && cmd != MEM_CLEARIRQ && cmd != MEM_RETURNIRQ
452 && cmd != FIONBIO && cmd != FIOASYNC)
456 * XXX the data is 16-bit due to a historical botch, so we use
457 * magic 16's instead of ICU_LEN and can't support 24 interrupts
459 * Even inspecting the state is privileged, since it gives a hint
460 * about how easily the randomness might be guessed.
462 intr = *(int16_t *)data;
463 interrupt_mask = 1 << intr;
465 /* Really handled in upper layer */
473 if (intr < 0 || intr >= 16)
475 if (interrupt_allowed & interrupt_mask)
477 interrupt_allowed |= interrupt_mask;
478 register_randintr(intr);
484 if (intr < 0 || intr >= 16)
486 if (!(interrupt_allowed & interrupt_mask))
488 interrupt_allowed &= ~interrupt_mask;
489 unregister_randintr(intr);
495 *(u_int16_t *)data = interrupt_allowed;
502 mmpoll(dev_t dev, int events, struct thread *td)
504 switch (minor(dev)) {
505 case 3: /* /dev/random */
506 return random_poll(dev, events, td);
507 case 4: /* /dev/urandom */
509 return seltrue(dev, events, td);
517 return ((major(dev) == mem_cdevsw.d_maj)
518 && minor(dev) == 12);
522 mem_drvinit(void *unused)
525 /* Initialise memory range handling */
526 if (mem_range_softc.mr_op != NULL)
527 mem_range_softc.mr_op->init(&mem_range_softc);
529 make_dev(&mem_cdevsw, 0, UID_ROOT, GID_KMEM, 0640, "mem");
530 make_dev(&mem_cdevsw, 1, UID_ROOT, GID_KMEM, 0640, "kmem");
531 make_dev(&mem_cdevsw, 2, UID_ROOT, GID_WHEEL, 0666, "null");
532 make_dev(&mem_cdevsw, 3, UID_ROOT, GID_WHEEL, 0644, "random");
533 make_dev(&mem_cdevsw, 4, UID_ROOT, GID_WHEEL, 0644, "urandom");
534 make_dev(&mem_cdevsw, 12, UID_ROOT, GID_WHEEL, 0666, "zero");
535 make_dev(&mem_cdevsw, 14, UID_ROOT, GID_WHEEL, 0600, "io");
538 SYSINIT(memdev,SI_SUB_DRIVERS,SI_ORDER_MIDDLE+CDEV_MAJOR,mem_drvinit,NULL)