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 $
48 #include <sys/param.h>
49 #include <sys/systm.h>
52 #include <sys/fcntl.h>
53 #include <sys/filio.h>
54 #include <sys/ioccom.h>
55 #include <sys/kernel.h>
56 #include <sys/malloc.h>
57 #include <sys/memrange.h>
59 #include <sys/random.h>
60 #include <sys/signalvar.h>
62 #include <sys/vnode.h>
64 #include <machine/frame.h>
65 #include <machine/psl.h>
66 #include <machine/specialreg.h>
67 #include <i386/isa/intr_machdep.h>
71 #include <vm/vm_extern.h>
74 static d_open_t mmopen;
75 static d_close_t mmclose;
77 static d_ioctl_t mmioctl;
78 static d_mmap_t memmmap;
79 static d_poll_t mmpoll;
82 static struct cdevsw mem_cdevsw = {
90 /* strategy */ nostrategy,
99 static struct random_softc random_softc[16];
102 MALLOC_DEFINE(M_MEMDESC, "memdesc", "memory range descriptors");
103 static int mem_ioctl __P((dev_t, u_long, caddr_t, int, struct proc *));
104 static int random_ioctl __P((dev_t, u_long, caddr_t, int, struct proc *));
106 struct mem_range_softc mem_range_softc;
110 mmclose(dev, flags, fmt, p)
116 switch (minor(dev)) {
118 p->p_md.md_regs->tf_eflags &= ~PSL_IOPL;
127 mmopen(dev, flags, fmt, p)
135 switch (minor(dev)) {
138 if ((flags & FWRITE) && securelevel > 0)
147 p->p_md.md_regs->tf_eflags |= PSL_IOPL;
156 mmrw(dev, uio, flags)
164 register struct iovec *iov;
168 while (uio->uio_resid > 0 && error == 0) {
170 if (iov->iov_len == 0) {
173 if (uio->uio_iovcnt < 0)
177 switch (minor(dev)) {
179 /* minor device 0 is physical memory */
183 pmap_kenter((vm_offset_t)ptvmmap, v);
184 o = (int)uio->uio_offset & PAGE_MASK;
185 c = (u_int)(PAGE_SIZE - ((int)iov->iov_base & PAGE_MASK));
186 c = min(c, (u_int)(PAGE_SIZE - o));
187 c = min(c, (u_int)iov->iov_len);
188 error = uiomove((caddr_t)&ptvmmap[o], (int)c, uio);
189 pmap_kremove((vm_offset_t)ptvmmap);
192 /* minor device 1 is kernel memory */
194 vm_offset_t addr, eaddr;
198 * Make sure that all of the pages are currently resident so
199 * that we don't create any zero-fill pages.
201 addr = trunc_page(uio->uio_offset);
202 eaddr = round_page(uio->uio_offset + c);
204 if (addr < (vm_offset_t)VADDR(PTDPTDI, 0))
206 if (eaddr >= (vm_offset_t)VADDR(APTDPTDI, 0))
208 for (; addr < eaddr; addr += PAGE_SIZE)
209 if (pmap_extract(kernel_pmap, addr) == 0)
212 if (!kernacc((caddr_t)(int)uio->uio_offset, c,
213 uio->uio_rw == UIO_READ ?
214 VM_PROT_READ : VM_PROT_WRITE))
216 error = uiomove((caddr_t)(int)uio->uio_offset, (int)c, uio);
220 /* minor device 2 is EOF/RATHOLE */
222 if (uio->uio_rw == UIO_READ)
227 /* minor device 3 (/dev/random) is source of filth on read, rathole on write */
229 if (uio->uio_rw == UIO_WRITE) {
235 malloc(PAGE_SIZE, M_TEMP, M_WAITOK);
236 c = min(iov->iov_len, PAGE_SIZE);
237 poolsize = read_random(buf, c);
241 if ((flags & IO_NDELAY) != 0)
242 return (EWOULDBLOCK);
245 c = min(c, poolsize);
246 error = uiomove(buf, (int)c, uio);
249 /* minor device 4 (/dev/urandom) is source of muck on read, rathole on write */
251 if (uio->uio_rw == UIO_WRITE) {
255 if (CURSIG(curproc) != 0) {
257 * Use tsleep() to get the error code right.
258 * It should return immediately.
260 error = tsleep(&random_softc[0],
261 PZERO | PCATCH, "urand", 1);
262 if (error != 0 && error != EWOULDBLOCK)
267 malloc(PAGE_SIZE, M_TEMP, M_WAITOK);
268 c = min(iov->iov_len, PAGE_SIZE);
269 poolsize = read_random_unlimited(buf, c);
270 c = min(c, poolsize);
271 error = uiomove(buf, (int)c, uio);
274 /* minor device 12 (/dev/zero) is source of nulls on read, rathole on write */
276 if (uio->uio_rw == UIO_WRITE) {
282 malloc(PAGE_SIZE, M_TEMP, M_WAITOK);
283 bzero(zbuf, PAGE_SIZE);
285 c = min(iov->iov_len, PAGE_SIZE);
286 error = uiomove(zbuf, (int)c, uio);
296 uio->uio_offset += c;
307 /*******************************************************\
308 * allow user processes to MMAP some memory sections *
309 * instead of going through read/write *
310 \*******************************************************/
312 memmmap(dev_t dev, vm_offset_t offset, int nprot)
317 /* minor device 0 is physical memory */
319 return i386_btop(offset);
321 /* minor device 1 is kernel memory */
323 return i386_btop(vtophys(offset));
331 mmioctl(dev, cmd, data, flags, p)
339 switch (minor(dev)) {
341 return mem_ioctl(dev, cmd, data, flags, p);
344 return random_ioctl(dev, cmd, data, flags, p);
350 * Operations for changing memory attributes.
352 * This is basically just an ioctl shim for mem_range_attr_get
353 * and mem_range_attr_set.
356 mem_ioctl(dev, cmd, data, flags, p)
364 struct mem_range_op *mo = (struct mem_range_op *)data;
365 struct mem_range_desc *md;
367 /* is this for us? */
368 if ((cmd != MEMRANGE_GET) &&
369 (cmd != MEMRANGE_SET))
372 /* any chance we can handle this? */
373 if (mem_range_softc.mr_op == NULL)
376 /* do we have any descriptors? */
377 if (mem_range_softc.mr_ndesc == 0)
382 nd = imin(mo->mo_arg[0], mem_range_softc.mr_ndesc);
384 md = (struct mem_range_desc *)
385 malloc(nd * sizeof(struct mem_range_desc),
386 M_MEMDESC, M_WAITOK);
387 error = mem_range_attr_get(md, &nd);
389 error = copyout(md, mo->mo_desc,
390 nd * sizeof(struct mem_range_desc));
393 nd = mem_range_softc.mr_ndesc;
399 md = (struct mem_range_desc *)malloc(sizeof(struct mem_range_desc),
400 M_MEMDESC, M_WAITOK);
401 error = copyin(mo->mo_desc, md, sizeof(struct mem_range_desc));
402 /* clamp description string */
403 md->mr_owner[sizeof(md->mr_owner) - 1] = 0;
405 error = mem_range_attr_set(md, &mo->mo_arg[0]);
413 * Implementation-neutral, kernel-callable functions for manipulating
414 * memory range attributes.
417 mem_range_attr_get(mrd, arg)
418 struct mem_range_desc *mrd;
421 /* can we handle this? */
422 if (mem_range_softc.mr_op == NULL)
426 *arg = mem_range_softc.mr_ndesc;
428 bcopy(mem_range_softc.mr_desc, mrd, (*arg) * sizeof(struct mem_range_desc));
434 mem_range_attr_set(mrd, arg)
435 struct mem_range_desc *mrd;
438 /* can we handle this? */
439 if (mem_range_softc.mr_op == NULL)
442 return (mem_range_softc.mr_op->set(&mem_range_softc, mrd, arg));
447 mem_range_AP_init(void)
449 if (mem_range_softc.mr_op && mem_range_softc.mr_op->initAP)
450 return (mem_range_softc.mr_op->initAP(&mem_range_softc));
455 random_ioctl(dev, cmd, data, flags, p)
462 static intrmask_t interrupt_allowed;
463 intrmask_t interrupt_mask;
465 struct random_softc *sc;
468 * We're the random or urandom device. The only ioctls are for
469 * selecting and inspecting which interrupts are used in the muck
470 * gathering business and the fcntl() stuff.
472 if (cmd != MEM_SETIRQ && cmd != MEM_CLEARIRQ && cmd != MEM_RETURNIRQ
473 && cmd != FIONBIO && cmd != FIOASYNC)
477 * XXX the data is 16-bit due to a historical botch, so we use
478 * magic 16's instead of ICU_LEN and can't support 24 interrupts
480 * Even inspecting the state is privileged, since it gives a hint
481 * about how easily the randomness might be guessed.
483 intr = *(int16_t *)data;
484 interrupt_mask = 1 << intr;
485 sc = &random_softc[intr];
487 /* Really handled in upper layer */
495 if (intr < 0 || intr >= 16)
497 if (interrupt_allowed & interrupt_mask)
499 interrupt_allowed |= interrupt_mask;
502 sc->sc_handler = intr_handler[intr];
503 intr_handler[intr] = add_interrupt_randomness;
504 sc->sc_arg = intr_unit[intr];
505 intr_unit[intr] = sc;
512 if (intr < 0 || intr >= 16)
514 if (!(interrupt_allowed & interrupt_mask))
516 interrupt_allowed &= ~interrupt_mask;
518 intr_handler[intr] = sc->sc_handler;
519 intr_unit[intr] = sc->sc_arg;
526 *(u_int16_t *)data = interrupt_allowed;
533 mmpoll(dev, events, p)
538 switch (minor(dev)) {
539 case 3: /* /dev/random */
540 return random_poll(dev, events, p);
541 case 4: /* /dev/urandom */
543 return seltrue(dev, events, p);
551 return ((major(dev) == mem_cdevsw.d_maj)
552 && minor(dev) == 12);
556 mem_drvinit(void *unused)
559 /* Initialise memory range handling */
560 if (mem_range_softc.mr_op != NULL)
561 mem_range_softc.mr_op->init(&mem_range_softc);
563 make_dev(&mem_cdevsw, 0, UID_ROOT, GID_KMEM, 0640, "mem");
564 make_dev(&mem_cdevsw, 1, UID_ROOT, GID_KMEM, 0640, "kmem");
565 make_dev(&mem_cdevsw, 2, UID_ROOT, GID_WHEEL, 0666, "null");
566 make_dev(&mem_cdevsw, 3, UID_ROOT, GID_WHEEL, 0644, "random");
567 make_dev(&mem_cdevsw, 4, UID_ROOT, GID_WHEEL, 0644, "urandom");
568 make_dev(&mem_cdevsw, 12, UID_ROOT, GID_WHEEL, 0666, "zero");
569 make_dev(&mem_cdevsw, 14, UID_ROOT, GID_WHEEL, 0600, "io");
572 SYSINIT(memdev,SI_SUB_DRIVERS,SI_ORDER_MIDDLE+CDEV_MAJOR,mem_drvinit,NULL)