diff options
Diffstat (limited to 'historic/mkswap.c')
| -rw-r--r-- | historic/mkswap.c | 212 |
1 files changed, 0 insertions, 212 deletions
diff --git a/historic/mkswap.c b/historic/mkswap.c deleted file mode 100644 index bb4e2249e..000000000 --- a/historic/mkswap.c +++ /dev/null @@ -1,212 +0,0 @@ -/* - * mkswap.c - set up a linux swap device - * - * (C) 1991 Linus Torvalds. This file may be redistributed as per - * the Linux copyright. - */ - -/* - * 20.12.91 - time began. Got VM working yesterday by doing this by hand. - * - * Usuage: mkswap [-c] device [size-in-blocks] - * - * -c for readablility checking (use it unless you are SURE!) - * - * The device may be a block device or a image of one, but this isn't - * enforced (but it's not much fun on a character device :-). - * - * Patches from jaggy@purplet.demon.co.uk (Mike Jagdis) to make the - * size-in-blocks parameter optional added Wed Feb 8 10:33:43 1995. - */ - -#include <stdio.h> -#include <unistd.h> -#include <string.h> -#include <fcntl.h> -#include <stdlib.h> -#include <sys/stat.h> - -#include <linux/mm.h> - -#ifndef __GNUC__ -#error "needs gcc for the bitop-__asm__'s" -#endif - -#ifndef __linux__ -#define volatile -#endif - -#define TEST_BUFFER_PAGES 8 - -static char * program_name = "mkswap"; -static char * device_name = NULL; -static int DEV = -1; -static long PAGES = 0; -static int check = 0; -static int badpages = 0; - -static char signature_page[PAGE_SIZE]; - -#define bitop(name,op) \ -static inline int name(char * addr,unsigned int nr) \ -{ \ -int __res; \ -__asm__ __volatile__("bt" op " %1,%2; adcl $0,%0" \ -:"=g" (__res) \ -:"r" (nr),"m" (*(addr)),"0" (0)); \ -return __res; \ -} - -bitop(bit,"") -bitop(setbit,"s") -bitop(clrbit,"r") - -/* - * Volatile to let gcc know that this doesn't return. When trying - * to compile this under minix, volatile gives a warning, as - * exit() isn't defined as volatile under minix. - */ -volatile void fatal_error(const char * fmt_string) -{ - fprintf(stderr,fmt_string,program_name,device_name); - exit(1); -} - -#define usage() fatal_error("Usage: %s [-c] /dev/name [blocks]\n") -#define die(str) fatal_error("%s: " str "\n") - -void check_blocks(void) -{ - unsigned int current_page; - int do_seek = 1; - static char buffer[PAGE_SIZE]; - - current_page = 0; - while (current_page < PAGES) { - if (!check) { - setbit(signature_page,current_page++); - continue; - } - if (do_seek && lseek(DEV,current_page*PAGE_SIZE,SEEK_SET) != - current_page*PAGE_SIZE) - die("seek failed in check_blocks"); - if (do_seek = (PAGE_SIZE != read(DEV, buffer, PAGE_SIZE))) { - clrbit(signature_page,current_page++); - badpages++; - continue; - } - setbit(signature_page,current_page++); - } - if (badpages) - printf("%d bad page%s\n",badpages,(badpages>1)?"s":""); -} - -static long valid_offset (int fd, int offset) -{ - char ch; - - if (lseek (fd, offset, 0) < 0) - return 0; - if (read (fd, &ch, 1) < 1) - return 0; - return 1; -} - -static int count_blocks (int fd) -{ - int high, low; - - low = 0; - for (high = 1; valid_offset (fd, high); high *= 2) - low = high; - while (low < high - 1) - { - const int mid = (low + high) / 2; - - if (valid_offset (fd, mid)) - low = mid; - else - high = mid; - } - valid_offset (fd, 0); - return (low + 1); -} - -static int get_size(const char *file) -{ - int fd; - int size; - - fd = open(file, O_RDWR); - if (fd < 0) { - perror(file); - exit(1); - } - if (ioctl(fd, BLKGETSIZE, &size) >= 0) { - close(fd); - return (size * 512); - } - - size = count_blocks(fd); - close(fd); - return size; -} - -int main(int argc, char ** argv) -{ - char * tmp; - struct stat statbuf; - int goodpages; - - memset(signature_page,0,PAGE_SIZE); - if (argc && *argv) - program_name = *argv; - while (argc-- > 1) { - argv++; - if (argv[0][0] != '-') - if (device_name) { - PAGES = strtol(argv[0],&tmp,0)>>2; - if (*tmp) - usage(); - } else - device_name = argv[0]; - else while (*++argv[0]) - switch (argv[0][0]) { - case 'c': check=1; break; - default: usage(); - } - } - if (device_name && !PAGES) { - PAGES = get_size(device_name) / PAGE_SIZE; - } - if (!device_name || PAGES<10) - usage(); - if (PAGES > 32688) /* 130752 blocks */ - PAGES=32688; -#if 0 - if (PAGES > 32768) - PAGES=32768; -#endif - DEV = open(device_name,O_RDWR); - if (DEV < 0 || fstat(DEV, &statbuf) < 0) { - perror(device_name); - exit(1); - } - if (!S_ISBLK(statbuf.st_mode)) - check=0; - else if (statbuf.st_rdev == 0x0300 || statbuf.st_rdev == 0x0340) - die("Will not try to make swapdevice on '%s'"); - check_blocks(); - if (!clrbit(signature_page,0)) - die("fatal: first page unreadable"); - goodpages = PAGES - badpages - 1; - if (!goodpages) - die("Unable to set up swap-space: unreadable"); - printf("Setting up swapspace, size = %d bytes\n",goodpages*PAGE_SIZE); - strncpy(signature_page+PAGE_SIZE-10,"SWAP-SPACE",10); - if (lseek(DEV, 0, SEEK_SET)) - die("unable to rewind swap-device"); - if (PAGE_SIZE != write(DEV, signature_page, PAGE_SIZE)) - die("unable to write signature page"); - return 0; -} |