/* $NetBSD: mem.c,v 1.10 2007/03/05 16:39:21 he 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. */ /* * 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. */ /* * Memory special file */ #include "opt_compat_netbsd.h" #include <sys/cdefs.h> __KERNEL_RCSID(0, "$NetBSD: mem.c,v 1.10 2007/03/05 16:39:21 he Exp $"); #include <sys/param.h> #include <sys/conf.h> #include <sys/buf.h> #include <sys/systm.h> #include <sys/uio.h> #include <sys/malloc.h> #include <sys/proc.h> #include <sys/fcntl.h> #include <machine/cpu.h> #include <machine/memcreg.h> #include <uvm/uvm_extern.h> void *zeropage; int physlock; 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, uio, flags) dev_t dev; struct uio *uio; int flags; { register vm_offset_t v; register int c; register struct iovec *iov; int error = 0; 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: /* * On arm26, there's no need to map in the * relevant page, as we've got physical memory * mapped in at another address and can just * use that. */ v = uio->uio_offset; c = min(iov->iov_len, MAXPHYS); /* XXX Should use pmap_find(). */ if (v < 0 || (char *)v + c > (char*)MEMC_PHYS_BASE + ptoa(physmem)) return EFAULT; error = uiomove((char*)MEMC_PHYS_BASE + uio->uio_offset, uio->uio_resid, uio); continue; case DEV_KMEM: v = uio->uio_offset; c = min(iov->iov_len, MAXPHYS); /* Allow reading from physically mapped space. */ if (((void *)v >= MEMC_PHYS_BASE && (char *)v + c < (char*)MEMC_PHYS_BASE + ptoa(physmem)) || uvm_kernacc((void *)v, c, uio->uio_rw == UIO_READ ? B_READ : B_WRITE)) error = uiomove((void *)v, c, uio); else return (EFAULT); break; case DEV_NULL: if (uio->uio_rw == UIO_WRITE) uio->uio_resid = 0; return (0); #ifdef COMPAT_16 case _DEV_ZERO_oARM: #endif case DEV_ZERO: if (uio->uio_rw == UIO_WRITE) { uio->uio_resid = 0; return (0); } if (zeropage == NULL) { zeropage = (void *) malloc(PAGE_SIZE, M_TEMP, M_WAITOK); bzero(zeropage, PAGE_SIZE); } c = min(iov->iov_len, PAGE_SIZE); error = uiomove(zeropage, c, uio); break; default: return (ENXIO); } } if (minor(dev) == DEV_MEM) { /*unlock:*/ if (physlock > 1) wakeup((void *)&physlock); physlock = 0; } return (error); } paddr_t mmmmap(dev, off, prot) dev_t dev; off_t off; int prot; { int ppn; /* * /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); /* minor device 0 is physical memory */ /* XXX This may botch our cacheing assumptions. Do we care? */ ppn = atop(off); if (ppn >= 0 && ppn < physmem) return ppn; return -1; }