projects / unix-history / blame
| Commit | Line | Data |
|---|---|---|
| 4bd1c0bf WN |
1 | /*- |
| 2 | * Copyright (c) 1990 The Regents of the University of California. | |
| 3 | * All rights reserved. | |
| 4 | * | |
| 5 | * This code is derived from software contributed to Berkeley by | |
| 6 | * William Jolitz. | |
| 7 | * | |
| 8 | * %sccs.include.noredist.c% | |
| 9 | * | |
| 9c09b4f2 | 10 | * @(#)mem.c 5.4 (Berkeley) %G% |
| 4bd1c0bf WN |
11 | */ |
| 12 | ||
| 01ebe5de BJ |
13 | /* |
| 14 | * Memory special file | |
| 15 | */ | |
| 16 | ||
| ab214bc8 BJ |
17 | #include "machine/pte.h" |
| 18 | ||
| 19 | #include "param.h" | |
| 20 | #include "dir.h" | |
| 21 | #include "user.h" | |
| 22 | #include "conf.h" | |
| 23 | #include "buf.h" | |
| 24 | #include "systm.h" | |
| 25 | #include "vm.h" | |
| 26 | #include "cmap.h" | |
| 27 | #include "uio.h" | |
| 01ebe5de | 28 | |
| 01ebe5de BJ |
29 | mmread(dev, uio) |
| 30 | dev_t dev; | |
| 31 | struct uio *uio; | |
| 32 | { | |
| 33 | ||
| 34 | return (mmrw(dev, uio, UIO_READ)); | |
| 35 | } | |
| 36 | ||
| 37 | mmwrite(dev, uio) | |
| 38 | dev_t dev; | |
| 39 | struct uio *uio; | |
| 40 | { | |
| 41 | ||
| 42 | return (mmrw(dev, uio, UIO_WRITE)); | |
| 43 | } | |
| 44 | ||
| 45 | mmrw(dev, uio, rw) | |
| 46 | dev_t dev; | |
| 47 | struct uio *uio; | |
| 48 | enum uio_rw rw; | |
| 49 | { | |
| 50 | register int o; | |
| 51 | register u_int c, v; | |
| 52 | register struct iovec *iov; | |
| 53 | int error = 0; | |
| 01ebe5de BJ |
54 | |
| 55 | ||
| 56 | while (uio->uio_resid > 0 && error == 0) { | |
| 57 | iov = uio->uio_iov; | |
| 58 | if (iov->iov_len == 0) { | |
| 59 | uio->uio_iov++; | |
| 60 | uio->uio_iovcnt--; | |
| 61 | if (uio->uio_iovcnt < 0) | |
| 62 | panic("mmrw"); | |
| 63 | continue; | |
| 64 | } | |
| 65 | switch (minor(dev)) { | |
| 66 | ||
| 67 | /* minor device 0 is physical memory */ | |
| 68 | case 0: | |
| 69 | v = btop(uio->uio_offset); | |
| 70 | if (v >= physmem) | |
| 71 | goto fault; | |
| 4bd1c0bf | 72 | *(int *)mmap = ctob(v) | PG_V | |
| 01ebe5de | 73 | (rw == UIO_READ ? PG_KR : PG_KW); |
| 9c09b4f2 | 74 | tlbflush(); |
| 01ebe5de BJ |
75 | o = (int)uio->uio_offset & PGOFSET; |
| 76 | c = (u_int)(NBPG - ((int)iov->iov_base & PGOFSET)); | |
| 77 | c = MIN(c, (u_int)(NBPG - o)); | |
| 78 | c = MIN(c, (u_int)iov->iov_len); | |
| 79 | error = uiomove((caddr_t)&vmmap[o], (int)c, rw, uio); | |
| 80 | continue; | |
| 81 | ||
| 82 | /* minor device 1 is kernel memory */ | |
| 83 | case 1: | |
| 01ebe5de BJ |
84 | c = iov->iov_len; |
| 85 | if (!kernacc((caddr_t)uio->uio_offset, c, rw == UIO_READ ? B_READ : B_WRITE)) | |
| 86 | goto fault; | |
| 87 | error = uiomove((caddr_t)uio->uio_offset, (int)c, rw, uio); | |
| 88 | continue; | |
| 89 | ||
| 90 | /* minor device 2 is EOF/RATHOLE */ | |
| 91 | case 2: | |
| 92 | if (rw == UIO_READ) | |
| 93 | return (0); | |
| 94 | c = iov->iov_len; | |
| 95 | break; | |
| 96 | ||
| 01ebe5de BJ |
97 | } |
| 98 | if (error) | |
| 99 | break; | |
| 100 | iov->iov_base += c; | |
| 101 | iov->iov_len -= c; | |
| 102 | uio->uio_offset += c; | |
| 103 | uio->uio_resid -= c; | |
| 104 | } | |
| 105 | return (error); | |
| 106 | fault: | |
| 107 | return (EFAULT); | |
| 108 | } |