623 lines
16 KiB
C
623 lines
16 KiB
C
/*
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* mkswap.c - set up a linux swap device
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*
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* (C) 1991 Linus Torvalds. This file may be redistributed as per
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* the Linux copyright.
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*/
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/*
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* 20.12.91 - time began. Got VM working yesterday by doing this by hand.
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*
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* Usage: mkswap [-c] [-vN] [-f] device [size-in-blocks]
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*
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* -c for readability checking. (Use it unless you are SURE!)
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* -vN for swap areas version N. (Only N=0,1 known today.)
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* -f for forcing swap creation even if it would smash partition table.
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*
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* The device may be a block device or an image of one, but this isn't
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* enforced (but it's not much fun on a character device :-).
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*
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* Patches from jaggy@purplet.demon.co.uk (Mike Jagdis) to make the
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* size-in-blocks parameter optional added Wed Feb 8 10:33:43 1995.
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*
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* Version 1 swap area code (for kernel 2.1.117), aeb, 981010.
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*
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* Sparc fixes, jj@ultra.linux.cz (Jakub Jelinek), 981201 - mangled by aeb.
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* V1_MAX_PAGES fixes, jj, 990325.
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* sparc64 fixes, jj, 000219.
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*
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* 1999-02-22 Arkadiusz Mi¶kiewicz <misiek@misiek.eu.org>
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* - added Native Language Support
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*
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*/
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#include <stdio.h>
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#include <unistd.h>
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#include <string.h>
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#include <fcntl.h>
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#include <stdlib.h>
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#include <sys/ioctl.h> /* for _IO */
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#include <sys/utsname.h>
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#include <sys/stat.h>
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#include "nls.h"
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#ifdef HAVE_asm_page_h
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#include <asm/page.h> /* for PAGE_SIZE and PAGE_SHIFT */
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/* we also get PAGE_SIZE via getpagesize() */
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/* recent glibc systems also define this in <sys/user.h> */
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#endif
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#ifndef _IO
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/* pre-1.3.45 */
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#define BLKGETSIZE 0x1260
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#else
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/* same on i386, m68k, arm; different on alpha, mips, sparc, ppc */
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#define BLKGETSIZE _IO(0x12,96)
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#endif
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static char * program_name = "mkswap";
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static char * device_name = NULL;
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static int DEV = -1;
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static long PAGES = 0;
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static int check = 0;
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static int badpages = 0;
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static int version = -1;
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#define MAKE_VERSION(p,q,r) (65536*(p) + 256*(q) + (r))
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static int
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linux_version_code(void) {
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struct utsname my_utsname;
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int p, q, r;
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if (uname(&my_utsname) == 0) {
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p = atoi(strtok(my_utsname.release, "."));
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q = atoi(strtok(NULL, "."));
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r = atoi(strtok(NULL, "."));
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return MAKE_VERSION(p,q,r);
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}
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return 0;
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}
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#ifdef __sparc__
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# ifdef __arch64__
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# define is_sparc64() 1
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# define is_be64() 1
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# else /* sparc32 */
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static int
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is_sparc64(void) {
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struct utsname un;
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static int sparc64 = -1;
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if (sparc64 != -1) return sparc64;
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sparc64 = 0;
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if (uname(&un) < 0) return 0;
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if (! strcmp(un.machine, "sparc64")) {
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sparc64 = 1;
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return 1;
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}
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if (strcmp(un.machine, "sparc"))
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return 0; /* Should not happen */
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#ifdef HAVE_personality
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{
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extern int personality(unsigned long);
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int oldpers;
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#define PERS_LINUX 0x00000000
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#define PERS_LINUX_32BIT 0x00800000
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#define PERS_LINUX32 0x00000008
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oldpers = personality(PERS_LINUX_32BIT);
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if (oldpers != -1) {
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if (personality(PERS_LINUX) != -1) {
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uname(&un);
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if (! strcmp(un.machine, "sparc64")) {
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sparc64 = 1;
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oldpers = PERS_LINUX32;
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}
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}
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personality(oldpers);
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}
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}
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#endif
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return sparc64;
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}
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# define is_be64() is_sparc64()
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# endif /* sparc32 */
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#else /* !sparc */
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# define is_be64() 0
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#endif
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/*
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* The definition of the union swap_header uses the constant PAGE_SIZE.
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* Unfortunately, on some architectures this depends on the hardware model,
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* and can only be found at run time -- we use getpagesize(), so that
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* we do not need separate binaries e.g. for sun4, sun4c/d/m and sun4u.
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*
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* Even more unfortunately, getpagesize() does not always return
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* the right information. For example, libc4 and libc5 do not use
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* the system call but invent a value themselves
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* (EXEC_PAGESIZE or NBPG * CLSIZE or NBPC), and thus it may happen
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* that e.g. on a sparc PAGE_SIZE=4096 and getpagesize() returns 8192.
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* What to do? Let us allow the user to specify the pagesize explicitly.
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*/
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static int user_pagesize = 0;
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static int kernel_pagesize; /* obtained via getpagesize(); */
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static int defined_pagesize = 0; /* PAGE_SIZE, when that exists */
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static int pagesize;
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static long *signature_page;
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struct swap_header_v1 {
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char bootbits[1024]; /* Space for disklabel etc. */
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unsigned int version;
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unsigned int last_page;
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unsigned int nr_badpages;
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unsigned int padding[125];
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unsigned int badpages[1];
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} *p;
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static void
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init_signature_page(void) {
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#ifdef PAGE_SIZE
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defined_pagesize = PAGE_SIZE;
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#endif
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kernel_pagesize = getpagesize();
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pagesize = kernel_pagesize;
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if (user_pagesize) {
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if ((user_pagesize & (user_pagesize-1)) ||
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user_pagesize < 1024) {
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fprintf(stderr, _("Bad user-specified page size %d\n"),
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user_pagesize);
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exit(1);
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}
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pagesize = user_pagesize;
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}
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if (user_pagesize && user_pagesize != kernel_pagesize &&
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user_pagesize != defined_pagesize)
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fprintf(stderr, _("Using user-specified page size %d, "
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"instead of the system values %d/%d\n"),
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pagesize, kernel_pagesize, defined_pagesize);
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else if (defined_pagesize && pagesize != defined_pagesize)
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fprintf(stderr, _("Assuming pages of size %d (not %d)\n"),
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pagesize, defined_pagesize);
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signature_page = (long *) malloc(pagesize);
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memset(signature_page,0,pagesize);
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p = (struct swap_header_v1 *) signature_page;
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}
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static void
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write_signature(char *sig) {
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char *sp = (char *) signature_page;
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strncpy(sp+pagesize-10, sig, 10);
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}
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#define V0_MAX_PAGES (8 * (pagesize - 10))
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/* Before 2.2.0pre9 */
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#define V1_OLD_MAX_PAGES ((0x7fffffff / pagesize) - 1)
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/* Since 2.2.0pre9:
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error if nr of pages >= SWP_OFFSET(SWP_ENTRY(0,~0UL))
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with variations on
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#define SWP_ENTRY(type,offset) (((type) << 1) | ((offset) << 8))
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#define SWP_OFFSET(entry) ((entry) >> 8)
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on the various architectures. Below the result - yuk.
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Machine pagesize SWP_ENTRY SWP_OFFSET bound+1 oldbound+2
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i386 2^12 o<<8 e>>8 1<<24 1<<19
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mips 2^12 o<<15 e>>15 1<<17 1<<19
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alpha 2^13 o<<40 e>>40 1<<24 1<<18
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m68k 2^12 o<<12 e>>12 1<<20 1<<19
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sparc 2^{12,13} (o&0x3ffff)<<9 (e>>9)&0x3ffff 1<<18 1<<{19,18}
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sparc64 2^13 o<<13 e>>13 1<<51 1<<18
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ppc 2^12 o<<8 e>>8 1<<24 1<<19
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armo 2^{13,14,15} o<<8 e>>8 1<<24 1<<{18,17,16}
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armv 2^12 o<<9 e>>9 1<<23 1<<19
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assuming that longs have 64 bits on alpha and sparc64 and 32 bits elsewhere.
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The bad part is that we need to know this since the kernel will
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refuse a swap space if it is too large.
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*/
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/* patch from jj - why does this differ from the above? */
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/* 32bit kernels have a second limitation of 2GB, sparc64 is limited by
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the size of virtual address space allocation for vmalloc */
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#if defined(__alpha__)
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#define V1_MAX_PAGES ((1 << 24) - 1)
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#elif defined(__mips__)
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#define V1_MAX_PAGES ((1 << 17) - 1)
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#elif defined(__sparc__)
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#define V1_MAX_PAGES (is_sparc64() ? ((3 << 29) - 1) : ((1 << 18) - 1))
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#else
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#define V1_MAX_PAGES V1_OLD_MAX_PAGES
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#endif
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/* man page now says:
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The maximum useful size of a swap area now depends on the architecture.
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It is roughly 2GB on i386, PPC, m68k, ARM, 1GB on sparc, 512MB on mips,
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128GB on alpha and 3TB on sparc64.
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*/
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#define MAX_BADPAGES ((pagesize-1024-128*sizeof(int)-10)/sizeof(int))
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/*
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* One more point of lossage - Linux swapspace really is a mess.
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* The definition of the bitmap used is architecture dependent,
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* and requires one to know whether the machine is bigendian,
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* and if so, whether it will use 32-bit or 64-bit units in
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* test_bit().
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* davem writes: "... is based upon an unsigned long type of
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* the cpu and the native endianness".
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* So, it seems we can write `unsigned long' below.
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* However, sparc64 uses 64-bit units in the kernel, while
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* mkswap may have been translated with 32-bit longs. Thus,
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* we need an explicit test for version 0 swap on sparc64.
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*/
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static void
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bit_set (unsigned long *addr, unsigned int nr) {
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unsigned int r, m;
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if(is_be64()) {
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unsigned long long *bitmap = (unsigned long long *) addr;
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unsigned long long bitnum = (unsigned long long) nr;
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unsigned long long rl, ml;
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bitmap += bitnum / (8 * sizeof(long long));
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rl = *bitmap;
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ml = 1ULL << (bitnum &
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(8ULL * (unsigned long long)sizeof(long long) - 1ULL));
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*bitmap = rl | ml;
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return;
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}
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addr += nr / (8 * sizeof(unsigned long));
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r = *addr;
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m = 1 << (nr & (8 * sizeof(unsigned long) - 1));
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*addr = r | m;
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}
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static int
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bit_test_and_clear (unsigned long *addr, unsigned int nr) {
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unsigned int r, m;
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if(is_be64()) {
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unsigned long long *bitmap = (unsigned long long *) addr;
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unsigned long long bitnum = (unsigned long long) nr;
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unsigned long long rl, ml;
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bitmap += bitnum / (8 * sizeof(long long));
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rl = *bitmap;
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ml = 1ULL << (bitnum &
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(8ULL * (unsigned long long)sizeof(long long) - 1ULL));
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*bitmap = rl & ~ml;
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return ((rl & ml) != 0ULL);
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}
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addr += nr / (8 * sizeof(unsigned long));
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r = *addr;
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m = 1 << (nr & (8 * sizeof(unsigned long) - 1));
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*addr = r & ~m;
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return (r & m) != 0;
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}
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static void
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usage(void) {
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fprintf(stderr,
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_("Usage: %s [-c] [-v0|-v1] [-pPAGESZ] /dev/name [blocks]\n"),
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program_name);
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exit(1);
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}
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static void
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die(const char *str) {
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fprintf(stderr, "%s: %s\n", program_name, str);
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exit(1);
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}
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static void
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page_ok(int page) {
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if (version==0)
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bit_set(signature_page, page);
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}
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static void
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page_bad(int page) {
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if (version == 0)
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bit_test_and_clear(signature_page, page);
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else {
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if (badpages == MAX_BADPAGES)
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die(_("too many bad pages"));
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p->badpages[badpages] = page;
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}
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badpages++;
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}
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static void
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check_blocks(void) {
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unsigned int current_page;
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int do_seek = 1;
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char *buffer;
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buffer = malloc(pagesize);
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if (!buffer)
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die(_("Out of memory"));
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current_page = 0;
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while (current_page < PAGES) {
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if (!check) {
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page_ok(current_page++);
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continue;
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}
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if (do_seek && lseek(DEV,current_page*pagesize,SEEK_SET) !=
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current_page*pagesize)
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die(_("seek failed in check_blocks"));
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if ((do_seek = (pagesize != read(DEV, buffer, pagesize)))) {
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page_bad(current_page++);
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continue;
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}
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page_ok(current_page++);
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}
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if (badpages == 1)
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printf(_("one bad page\n"));
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else if (badpages > 1)
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printf(_("%d bad pages\n"), badpages);
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}
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static long
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valid_offset (int fd, int offset) {
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char ch;
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if (lseek (fd, offset, 0) < 0)
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return 0;
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if (read (fd, &ch, 1) < 1)
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return 0;
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return 1;
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}
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static int
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find_size (int fd) {
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unsigned int high, low;
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low = 0;
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for (high = 1; high > 0 && valid_offset (fd, high); high *= 2)
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low = high;
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while (low < high - 1)
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{
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const int mid = (low + high) / 2;
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if (valid_offset (fd, mid))
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low = mid;
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else
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high = mid;
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}
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return (low + 1);
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}
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/* return size in pages, to avoid integer overflow */
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static long
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get_size(const char *file) {
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int fd;
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long size;
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fd = open(file, O_RDONLY);
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if (fd < 0) {
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perror(file);
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exit(1);
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}
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if (ioctl(fd, BLKGETSIZE, &size) >= 0) {
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int sectors_per_page = pagesize/512;
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size /= sectors_per_page;
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} else {
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size = find_size(fd) / pagesize;
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}
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close(fd);
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return size;
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}
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|
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static int
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isnzdigit(char c) {
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return (c >= '1' && c <= '9');
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}
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|
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int
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main(int argc, char ** argv) {
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struct stat statbuf;
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int i, sz;
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int maxpages;
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int goodpages;
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int offset;
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int force = 0;
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char *block_count = 0;
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char *pp;
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program_name = (argc && *argv) ? argv[0] : "fsck.minix";
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if ((pp = strrchr(program_name, '/')) != NULL)
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program_name = pp+1;
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|
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setlocale(LC_ALL, "");
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bindtextdomain(PACKAGE, LOCALEDIR);
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textdomain(PACKAGE);
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|
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if (argc == 2 &&
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(!strcmp(argv[1], "-V") || !strcmp(argv[1], "--version"))) {
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printf(_("%s from %s\n"), program_name, util_linux_version);
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exit(0);
|
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}
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|
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for (i=1; i<argc; i++) {
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if (argv[i][0] == '-') {
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switch (argv[i][1]) {
|
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case 'c':
|
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check=1;
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break;
|
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case 'f':
|
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force=1;
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break;
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case 'p':
|
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pp = argv[i]+2;
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if (!*pp && i+1 < argc)
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pp = argv[++i];
|
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if (isnzdigit(*pp))
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user_pagesize=atoi(pp);
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else
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usage();
|
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break;
|
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case 'v':
|
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version = atoi(argv[i]+2);
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break;
|
|
default:
|
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usage();
|
|
}
|
|
} else if (!device_name) {
|
|
device_name = argv[i];
|
|
} else if (!block_count) {
|
|
block_count = argv[i];
|
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} else
|
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usage();
|
|
}
|
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|
|
init_signature_page(); /* get pagesize */
|
|
|
|
if (!device_name) {
|
|
fprintf(stderr,
|
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_("%s: error: Nowhere to set up swap on?\n"),
|
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program_name);
|
|
usage();
|
|
}
|
|
if (block_count) {
|
|
/* this silly user specified the number of blocks
|
|
explicitly */
|
|
char *tmp;
|
|
int blocks_per_page = pagesize/1024;
|
|
PAGES = strtol(block_count,&tmp,0)/blocks_per_page;
|
|
if (*tmp)
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|
usage();
|
|
}
|
|
sz = get_size(device_name);
|
|
if (!PAGES) {
|
|
PAGES = sz;
|
|
} else if (PAGES > sz && !force) {
|
|
fprintf(stderr,
|
|
_("%s: error: "
|
|
"size %ld is larger than device size %d\n"),
|
|
program_name,
|
|
PAGES*(pagesize/1024), sz*(pagesize/1024));
|
|
exit(1);
|
|
}
|
|
|
|
if (version == -1) {
|
|
/* use version 1 as default, if possible */
|
|
if (PAGES <= V0_MAX_PAGES && PAGES > V1_MAX_PAGES)
|
|
version = 0;
|
|
else if (linux_version_code() < MAKE_VERSION(2,1,117))
|
|
version = 0;
|
|
else if (pagesize < 2048)
|
|
version = 0;
|
|
else
|
|
version = 1;
|
|
}
|
|
if (version != 0 && version != 1) {
|
|
fprintf(stderr, _("%s: error: unknown version %d\n"),
|
|
program_name, version);
|
|
usage();
|
|
}
|
|
if (PAGES < 10) {
|
|
fprintf(stderr,
|
|
_("%s: error: swap area needs to be at least %ldkB\n"),
|
|
program_name, (long)(10 * pagesize / 1024));
|
|
usage();
|
|
}
|
|
#if 0
|
|
maxpages = ((version == 0) ? V0_MAX_PAGES : V1_MAX_PAGES);
|
|
#else
|
|
if (!version)
|
|
maxpages = V0_MAX_PAGES;
|
|
else if (linux_version_code() >= MAKE_VERSION(2,2,1))
|
|
maxpages = V1_MAX_PAGES;
|
|
else {
|
|
maxpages = V1_OLD_MAX_PAGES;
|
|
if (maxpages > V1_MAX_PAGES)
|
|
maxpages = V1_MAX_PAGES;
|
|
}
|
|
#endif
|
|
if (PAGES > maxpages) {
|
|
PAGES = maxpages;
|
|
fprintf(stderr, _("%s: warning: truncating swap area to %ldkB\n"),
|
|
program_name, PAGES * pagesize / 1024);
|
|
}
|
|
|
|
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'"));
|
|
|
|
#ifdef __sparc__
|
|
if (!force && version == 0) {
|
|
/* Don't overwrite partition table unless forced */
|
|
unsigned char *buffer = (unsigned char *)signature_page;
|
|
unsigned short *q, sum;
|
|
|
|
if (read(DEV, buffer, 512) != 512)
|
|
die(_("fatal: first page unreadable"));
|
|
if (buffer[508] == 0xDA && buffer[509] == 0xBE) {
|
|
q = (unsigned short *)(buffer + 510);
|
|
for (sum = 0; q >= (unsigned short *) buffer;)
|
|
sum ^= *q--;
|
|
if (!sum) {
|
|
fprintf(stderr, _("\
|
|
%s: Device '%s' contains a valid Sun disklabel.\n\
|
|
This probably means creating v0 swap would destroy your partition table\n\
|
|
No swap created. If you really want to create swap v0 on that device, use\n\
|
|
the -f option to force it.\n"),
|
|
program_name, device_name);
|
|
exit(1);
|
|
}
|
|
}
|
|
}
|
|
#endif
|
|
|
|
if (version == 0 || check)
|
|
check_blocks();
|
|
if (version == 0 && !bit_test_and_clear(signature_page,0))
|
|
die(_("fatal: first page unreadable"));
|
|
if (version == 1) {
|
|
p->version = version;
|
|
p->last_page = PAGES-1;
|
|
p->nr_badpages = badpages;
|
|
}
|
|
|
|
goodpages = PAGES - badpages - 1;
|
|
if (goodpages <= 0)
|
|
die(_("Unable to set up swap-space: unreadable"));
|
|
printf(_("Setting up swapspace version %d, size = %ld bytes\n"),
|
|
version, (long)(goodpages*pagesize));
|
|
write_signature((version == 0) ? "SWAP-SPACE" : "SWAPSPACE2");
|
|
|
|
offset = ((version == 0) ? 0 : 1024);
|
|
if (lseek(DEV, offset, SEEK_SET) != offset)
|
|
die(_("unable to rewind swap-device"));
|
|
if (write(DEV,(char*)signature_page+offset, pagesize-offset)
|
|
!= pagesize-offset)
|
|
die(_("unable to write signature page"));
|
|
|
|
/*
|
|
* A subsequent swapon() will fail if the signature
|
|
* is not actually on disk. (This is a kernel bug.)
|
|
*/
|
|
#ifdef HAVE_fsync
|
|
if (fsync(DEV))
|
|
die(_("fsync failed"));
|
|
#endif
|
|
return 0;
|
|
}
|