/* $OpenBSD: mem.c,v 1.8 2008/05/04 09:57:46 martin Exp $ */ /* $NetBSD: mem.c,v 1.11 2003/10/16 12:02:58 jdolecek 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 #include #include #include #include #include #include #include #include #include #include extern char *memhook; /* poor name! */ caddr_t zeropage; int physlock; /* open counter for aperture */ #ifdef APERTURE static int ap_open_count = 0; extern int allowaperture; #endif /*ARGSUSED*/ int mmopen(dev, flag, mode, p) dev_t dev; int flag, mode; struct proc *p; { switch (minor(dev)) { case 0: case 1: case 2: case 12: break; #ifdef APERTURE case 4: if (suser(p, 0) != 0 || !allowaperture) return (EPERM); /* authorize only one simultaneous open() */ if (ap_open_count > 0) return(EPERM); ap_open_count++; break; #endif default: return (ENXIO); } return (0); } /*ARGSUSED*/ int mmclose(dev, flag, mode, p) dev_t dev; int flag, mode; struct proc *p; { #ifdef APERTURE if (minor(dev) == 4) ap_open_count--; #endif return (0); } #define DEV_MEM 0 #define DEV_KMEM 1 #define DEV_NULL 2 #define DEV_ZERO 12 /*ARGSUSED*/ int mmrw(dev, uio, flags) dev_t dev; struct uio *uio; int flags; { register vaddr_t o, v; register int c; register struct iovec *iov; int error = 0; vm_prot_t prot; if (minor(dev) == DEV_MEM) { /* lock against other uses of shared vmmap */ while (physlock > 0) { physlock++; error = tsleep((caddr_t)&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; prot = uio->uio_rw == UIO_READ ? VM_PROT_READ : VM_PROT_WRITE; pmap_enter(pmap_kernel(), (vaddr_t)memhook, 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((caddr_t)memhook + o, c, uio); pmap_remove(pmap_kernel(), (vaddr_t)memhook, (vaddr_t)memhook + PAGE_SIZE); pmap_update(pmap_kernel()); break; case DEV_KMEM: v = uio->uio_offset; c = min(iov->iov_len, MAXPHYS); if (!uvm_kernacc((caddr_t)v, c, uio->uio_rw == UIO_READ ? B_READ : B_WRITE)) return (EFAULT); error = uiomove((caddr_t)v, c, uio); break; case DEV_NULL: if (uio->uio_rw == UIO_WRITE) uio->uio_resid = 0; return (0); case DEV_ZERO: if (uio->uio_rw == UIO_WRITE) { uio->uio_resid = 0; return (0); } if (zeropage == NULL) zeropage = malloc(PAGE_SIZE, M_TEMP, M_WAITOK | M_ZERO); 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((caddr_t)&physlock); physlock = 0; } return (error); } paddr_t mmmmap(dev, off, prot) dev_t dev; off_t off; int prot; { struct proc *p = curproc; /* XXX */ /* * /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 */ if ((paddr_t)off >= ptoa((paddr_t)physmem) && suser(p, 0) != 0) return -1; return atop(off); } /*ARGSUSED*/ int mmioctl(dev_t dev, u_long cmd, caddr_t data, int flags, struct proc *p) { return (EOPNOTSUPP); }