/* $NetBSD: mem.c,v 1.25 2007/03/05 12:30:38 tsutsui Exp $ */ /* * This file was taken from mvme68k/mvme68k/mem.c * should probably be re-synced when needed. * Darrin B. Jewell <jewell@mit.edu> Tue Nov 10 05:07:16 1998 * original cvs id: NetBSD: mem.c,v 1.5 1998/08/22 10:55:35 scw Exp */ /* * Copyright (c) 1982, 1986, 1990, 1993 * The Regents of the University of California. All rights reserved. * * This code is derived from software contributed to Berkeley by * the Systems Programming Group of the University of Utah Computer * Science Department. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * @(#)mem.c 8.3 (Berkeley) 1/12/94 */ /* * Copyright (c) 1988 University of Utah. * * This code is derived from software contributed to Berkeley by * the Systems Programming Group of the University of Utah Computer * Science Department. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by the University of * California, Berkeley and its contributors. * 4. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * @(#)mem.c 8.3 (Berkeley) 1/12/94 */ /* * Memory special file */ #include <sys/cdefs.h> __KERNEL_RCSID(0, "$NetBSD: mem.c,v 1.25 2007/03/05 12:30:38 tsutsui Exp $"); #include <sys/param.h> #include <sys/systm.h> #include <sys/buf.h> #include <sys/conf.h> #include <sys/malloc.h> #include <sys/proc.h> #include <sys/uio.h> #include <machine/cpu.h> #include <uvm/uvm_extern.h> extern u_int lowram; static void *devzeropage; dev_type_read(mmrw); dev_type_ioctl(mmioctl); dev_type_mmap(mmmmap); const struct cdevsw mem_cdevsw = { nullopen, nullclose, mmrw, mmrw, mmioctl, nostop, notty, nopoll, mmmmap, nokqfilter, }; /*ARGSUSED*/ int mmrw(dev_t dev, struct uio *uio, int flags) { vaddr_t o, v; int c; struct iovec *iov; int error = 0; static int physlock; vm_prot_t prot; if (minor(dev) == DEV_MEM) { /* lock against other uses of shared vmmap */ while (physlock > 0) { physlock++; error = tsleep(&physlock, PZERO | PCATCH, "mmrw", 0); if (error) return (error); } physlock = 1; } while (uio->uio_resid > 0 && error == 0) { iov = uio->uio_iov; if (iov->iov_len == 0) { uio->uio_iov++; uio->uio_iovcnt--; if (uio->uio_iovcnt < 0) panic("mmrw"); continue; } switch (minor(dev)) { case DEV_MEM: v = uio->uio_offset; #ifndef DEBUG /* allow reads only in RAM (except for DEBUG) */ if (v >= 0xFFFFFFFC || v < lowram) { error = EFAULT; goto unlock; } #endif prot = uio->uio_rw == UIO_READ ? VM_PROT_READ : VM_PROT_WRITE; pmap_enter(pmap_kernel(), (vaddr_t)vmmap, trunc_page(v), prot, prot|PMAP_WIRED); pmap_update(pmap_kernel()); o = uio->uio_offset & PGOFSET; c = min(uio->uio_resid, (int)(PAGE_SIZE - o)); error = uiomove(vmmap + o, c, uio); pmap_remove(pmap_kernel(), (vaddr_t)vmmap, (vaddr_t)vmmap + PAGE_SIZE); pmap_update(pmap_kernel()); continue; case DEV_KMEM: v = uio->uio_offset; c = min(iov->iov_len, MAXPHYS); if (!uvm_kernacc((void *)v, c, uio->uio_rw == UIO_READ ? B_READ : B_WRITE)) return (EFAULT); error = uiomove((void *)v, c, uio); continue; case DEV_NULL: if (uio->uio_rw == UIO_WRITE) uio->uio_resid = 0; return (0); case DEV_ZERO: if (uio->uio_rw == UIO_WRITE) { c = iov->iov_len; break; } /* * On the first call, allocate and zero a page * of memory for use with /dev/zero. * * XXX on the hp300 we already know where there * is a global zeroed page, the null segment table. */ if (devzeropage == NULL) { extern void *Segtabzero; devzeropage = Segtabzero; } c = min(iov->iov_len, PAGE_SIZE); error = uiomove(devzeropage, c, uio); continue; default: return (ENXIO); } if (error) break; iov->iov_base = (char *)iov->iov_base + c; iov->iov_len -= c; uio->uio_offset += c; uio->uio_resid -= c; } if (minor(dev) == DEV_MEM) { #ifndef DEBUG unlock: #endif if (physlock > 1) wakeup((void *)&physlock); physlock = 0; } return (error); } paddr_t mmmmap(dev_t dev, off_t off, int prot) { /* * /dev/mem is the only one that makes sense through this * interface. For /dev/kmem any physaddr we return here * could be transient and hence incorrect or invalid at * a later time. /dev/null just doesn't make any sense * and /dev/zero is a hack that is handled via the default * pager in mmap(). */ if (minor(dev) != DEV_MEM) return (-1); /* * Allow access only in RAM. * * XXX could be extended to allow access to IO space but must * be very careful. */ if ((u_int)off < lowram || (u_int)off >= 0xFFFFFFFC) return (-1); return (m68k_btop((u_int)off)); }