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-rw-r--r--disk-utils/mkswap.c672
1 files changed, 672 insertions, 0 deletions
diff --git a/disk-utils/mkswap.c b/disk-utils/mkswap.c
new file mode 100644
index 0000000..34fe687
--- /dev/null
+++ b/disk-utils/mkswap.c
@@ -0,0 +1,672 @@
+/*
+ * 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.
+ *
+ * Usage: mkswap [-c] [-vN] [-f] device [size-in-blocks]
+ *
+ * -c for readability checking. (Use it unless you are SURE!)
+ * -vN for swap areas version N. (Only N=0,1 known today.)
+ * -f for forcing swap creation even if it would smash partition table.
+ *
+ * The device may be a block device or an 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.
+ *
+ * Version 1 swap area code (for kernel 2.1.117), aeb, 981010.
+ *
+ * Sparc fixes, jj@ultra.linux.cz (Jakub Jelinek), 981201 - mangled by aeb.
+ * V1_MAX_PAGES fixes, jj, 990325.
+ * sparc64 fixes, jj, 000219.
+ *
+ * 1999-02-22 Arkadiusz Mi¶kiewicz <misiek@pld.ORG.PL>
+ * - added Native Language Support
+ *
+ */
+
+#include <stdio.h>
+#include <unistd.h>
+#include <string.h>
+#include <fcntl.h>
+#include <stdlib.h>
+#include <limits.h>
+#include <mntent.h>
+#include <sys/utsname.h>
+#include <sys/stat.h>
+#include <errno.h>
+#include <getopt.h>
+#ifdef HAVE_LIBSELINUX
+#include <selinux/selinux.h>
+#include <selinux/context.h>
+#endif
+
+#include "linux_version.h"
+#include "swapheader.h"
+#include "strutils.h"
+#include "nls.h"
+#include "blkdev.h"
+#include "pathnames.h"
+#include "wholedisk.h"
+#include "all-io.h"
+#include "xalloc.h"
+#include "c.h"
+#include "closestream.h"
+#include "ismounted.h"
+
+#ifdef HAVE_LIBUUID
+# include <uuid.h>
+#endif
+
+#ifdef HAVE_LIBBLKID
+# include <blkid.h>
+#endif
+
+static char *device_name = NULL;
+static int DEV = -1;
+static unsigned long long PAGES = 0;
+static unsigned long badpages = 0;
+static int check = 0;
+
+#define SELINUX_SWAPFILE_TYPE "swapfile_t"
+
+#ifdef __sparc__
+# ifdef __arch64__
+# define is_sparc64() 1
+# define is_be64() 1
+# else /* sparc32 */
+static int
+is_sparc64(void)
+{
+ struct utsname un;
+ static int sparc64 = -1;
+
+ if (sparc64 != -1)
+ return sparc64;
+ sparc64 = 0;
+
+ if (uname(&un) < 0)
+ return 0;
+ if (! strcmp(un.machine, "sparc64")) {
+ sparc64 = 1;
+ return 1;
+ }
+ if (strcmp(un.machine, "sparc"))
+ return 0; /* Should not happen */
+
+#ifdef HAVE_PERSONALITY
+ {
+ extern int personality(unsigned long);
+ int oldpers;
+#define PERS_LINUX 0x00000000
+#define PERS_LINUX_32BIT 0x00800000
+#define PERS_LINUX32 0x00000008
+
+ oldpers = personality(PERS_LINUX_32BIT);
+ if (oldpers != -1) {
+ if (personality(PERS_LINUX) != -1) {
+ uname(&un);
+ if (! strcmp(un.machine, "sparc64")) {
+ sparc64 = 1;
+ oldpers = PERS_LINUX32;
+ }
+ }
+ personality(oldpers);
+ }
+ }
+#endif
+
+ return sparc64;
+}
+# define is_be64() is_sparc64()
+# endif /* sparc32 */
+#else /* !sparc */
+# define is_be64() 0
+#endif
+
+/*
+ * The definition of the union swap_header uses the kernel constant PAGE_SIZE.
+ * Unfortunately, on some architectures this depends on the hardware model, and
+ * can only be found at run time -- we use getpagesize(), so that we do not
+ * need separate binaries e.g. for sun4, sun4c/d/m and sun4u.
+ *
+ * Even more unfortunately, getpagesize() does not always return the right
+ * information. For example, libc4, libc5 and glibc 2.0 do not use the system
+ * call but invent a value themselves (EXEC_PAGESIZE or NBPG * CLSIZE or NBPC),
+ * and thus it may happen that e.g. on a sparc kernel PAGE_SIZE=4096 and
+ * getpagesize() returns 8192.
+ *
+ * What to do? Let us allow the user to specify the pagesize explicitly.
+ *
+ */
+static unsigned int user_pagesize;
+static unsigned int pagesize;
+static unsigned long *signature_page = NULL;
+
+static void
+init_signature_page(void)
+{
+
+ unsigned int kernel_pagesize = pagesize = getpagesize();
+
+ if (user_pagesize) {
+ if (!is_power_of_2(user_pagesize) ||
+ user_pagesize < sizeof(struct swap_header_v1_2) + 10)
+ errx(EXIT_FAILURE,
+ _("Bad user-specified page size %u"),
+ user_pagesize);
+ pagesize = user_pagesize;
+ }
+
+ if (user_pagesize && user_pagesize != kernel_pagesize)
+ warnx(_("Using user-specified page size %d, "
+ "instead of the system value %d"),
+ pagesize, kernel_pagesize);
+
+ signature_page = (unsigned long *) xcalloc(1, pagesize);
+}
+
+static void
+write_signature(char *sig)
+{
+ char *sp = (char *) signature_page;
+
+ strncpy(sp + pagesize - 10, sig, 10);
+}
+
+static void
+write_uuid_and_label(unsigned char *uuid, char *volume_name)
+{
+ struct swap_header_v1_2 *h;
+
+ /* Sanity check */
+ if (sizeof(struct swap_header_v1) !=
+ sizeof(struct swap_header_v1_2)) {
+ warnx(_("Bad swap header size, no label written."));
+ return;
+ }
+
+ h = (struct swap_header_v1_2 *) signature_page;
+ if (uuid)
+ memcpy(h->uuid, uuid, sizeof(h->uuid));
+ if (volume_name) {
+ xstrncpy(h->volume_name, volume_name, sizeof(h->volume_name));
+ if (strlen(volume_name) > strlen(h->volume_name))
+ warnx(_("Label was truncated."));
+ }
+ if (uuid || volume_name) {
+ if (volume_name)
+ printf("LABEL=%s, ", h->volume_name);
+ else
+ printf(_("no label, "));
+#ifdef HAVE_LIBUUID
+ if (uuid) {
+ char uuid_string[37];
+ uuid_unparse(uuid, uuid_string);
+ printf("UUID=%s\n", uuid_string);
+ } else
+#endif
+ printf(_("no uuid\n"));
+ }
+}
+
+/*
+ * Find out what the maximum amount of swap space is that the kernel will
+ * handle. This wouldn't matter if the kernel just used as much of the
+ * swap space as it can handle, but until 2.3.4 it would return an error
+ * to swapon() if the swapspace was too large.
+ */
+/* Before 2.2.0pre9 */
+#define V1_OLD_MAX_PAGES ((0x7fffffff / pagesize) - 1)
+/* Since 2.2.0pre9, before 2.3.4:
+ error if nr of pages >= SWP_OFFSET(SWP_ENTRY(0,~0UL))
+ with variations on
+ #define SWP_ENTRY(type,offset) (((type) << 1) | ((offset) << 8))
+ #define SWP_OFFSET(entry) ((entry) >> 8)
+ on the various architectures. Below the result - yuk.
+
+ Machine pagesize SWP_ENTRY SWP_OFFSET bound+1 oldbound+2
+ i386 2^12 o<<8 e>>8 1<<24 1<<19
+ mips 2^12 o<<15 e>>15 1<<17 1<<19
+ alpha 2^13 o<<40 e>>40 1<<24 1<<18
+ m68k 2^12 o<<12 e>>12 1<<20 1<<19
+ sparc 2^{12,13} (o&0x3ffff)<<9 (e>>9)&0x3ffff 1<<18 1<<{19,18}
+ sparc64 2^13 o<<13 e>>13 1<<51 1<<18
+ ppc 2^12 o<<8 e>>8 1<<24 1<<19
+ armo 2^{13,14,15} o<<8 e>>8 1<<24 1<<{18,17,16}
+ armv 2^12 o<<9 e>>9 1<<23 1<<19
+
+ assuming that longs have 64 bits on alpha and sparc64 and 32 bits elsewhere.
+
+ The bad part is that we need to know this since the kernel will
+ refuse a swap space if it is too large.
+*/
+/* patch from jj - why does this differ from the above? */
+/* 32bit kernels have a second limitation of 2GB, sparc64 is limited by
+ the size of virtual address space allocation for vmalloc */
+#if defined(__alpha__)
+#define V1_MAX_PAGES ((1 << 24) - 1)
+#elif defined(__mips__)
+#define V1_MAX_PAGES ((1 << 17) - 1)
+#elif defined(__sparc__)
+#define V1_MAX_PAGES (is_sparc64() ? ((3 << 29) - 1) : ((1 << 18) - 1))
+#elif defined(__ia64__)
+/*
+ * The actual size will depend on the amount of virtual address space
+ * available to vmalloc the swap map.
+ */
+#define V1_MAX_PAGES ((1UL << 54) - 1)
+#else
+#define V1_MAX_PAGES V1_OLD_MAX_PAGES
+#endif
+/* man page now says:
+The maximum useful size of a swap area now depends on the architecture.
+It is roughly 2GB on i386, PPC, m68k, ARM, 1GB on sparc, 512MB on mips,
+128GB on alpha and 3TB on sparc64.
+*/
+
+#define MAX_BADPAGES ((pagesize-1024-128*sizeof(int)-10)/sizeof(int))
+#define MIN_GOODPAGES 10
+
+static void __attribute__ ((__noreturn__)) usage(FILE *out)
+{
+ fprintf(out,
+ _("\nUsage:\n"
+ " %s [options] device [size]\n"),
+ program_invocation_short_name);
+
+ fprintf(out, _(
+ "\nOptions:\n"
+ " -c, --check check bad blocks before creating the swap area\n"
+ " -f, --force allow swap size area be larger than device\n"
+ " -p, --pagesize SIZE specify page size in bytes\n"
+ " -L, --label LABEL specify label\n"
+ " -v, --swapversion NUM specify swap-space version number\n"
+ " -U, --uuid UUID specify the uuid to use\n"
+ " -V, --version output version information and exit\n"
+ " -h, --help display this help and exit\n\n"));
+
+ exit(out == stderr ? EXIT_FAILURE : EXIT_SUCCESS);
+}
+
+static void
+page_bad(int page)
+{
+ struct swap_header_v1_2 *p = (struct swap_header_v1_2 *) signature_page;
+
+ if (badpages == MAX_BADPAGES)
+ errx(EXIT_FAILURE, _("too many bad pages"));
+ p->badpages[badpages] = page;
+ badpages++;
+}
+
+static void
+check_blocks(void)
+{
+ unsigned int current_page;
+ int do_seek = 1;
+ char *buffer;
+
+ buffer = xmalloc(pagesize);
+ current_page = 0;
+ while (current_page < PAGES) {
+ if (do_seek && lseek(DEV,current_page*pagesize,SEEK_SET) !=
+ current_page*pagesize)
+ errx(EXIT_FAILURE, _("seek failed in check_blocks"));
+ if ((do_seek = (pagesize != read(DEV, buffer, pagesize))))
+ page_bad(current_page);
+ current_page++;
+ }
+ if (badpages == 1)
+ printf(_("one bad page\n"));
+ else if (badpages > 1)
+ printf(_("%lu bad pages\n"), badpages);
+ free(buffer);
+}
+
+/* return size in pages */
+static unsigned long long
+get_size(const char *file)
+{
+ int fd;
+ unsigned long long size;
+
+ fd = open(file, O_RDONLY);
+ if (fd < 0) {
+ perror(file);
+ exit(EXIT_FAILURE);
+ }
+ if (blkdev_get_size(fd, &size) == 0)
+ size /= pagesize;
+
+ close(fd);
+ return size;
+}
+
+#ifdef HAVE_LIBBLKID
+static blkid_probe
+new_prober(int fd)
+{
+ blkid_probe pr = blkid_new_probe();
+ if (!pr)
+ errx(EXIT_FAILURE, _("unable to alloc new libblkid probe"));
+ if (blkid_probe_set_device(pr, fd, 0, 0))
+ errx(EXIT_FAILURE, _("unable to assign device to libblkid probe"));
+ return pr;
+}
+#endif
+
+static void
+wipe_device(int fd, const char *devname, int force, int is_blkdevice)
+{
+ char *type = NULL;
+ int whole = 0;
+ int zap = 1;
+#ifdef HAVE_LIBBLKID
+ blkid_probe pr = NULL;
+#endif
+ if (!force) {
+ if (lseek(fd, 0, SEEK_SET) != 0)
+ errx(EXIT_FAILURE, _("unable to rewind swap-device"));
+
+ if (is_blkdevice && is_whole_disk_fd(fd, devname)) {
+ /* don't zap bootbits on whole disk -- we know nothing
+ * about bootloaders on the device */
+ whole = 1;
+ zap = 0;
+ } else {
+#ifdef HAVE_LIBBLKID
+ pr = new_prober(fd);
+ blkid_probe_enable_partitions(pr, 1);
+ blkid_probe_enable_superblocks(pr, 0);
+
+ if (blkid_do_fullprobe(pr) == 0 &&
+ blkid_probe_lookup_value(pr, "PTTYPE",
+ (const char **) &type, NULL) == 0 &&
+ type) {
+ type = xstrdup(type);
+ zap = 0;
+ }
+#else
+ /* don't zap if compiled without libblkid */
+ zap = 0;
+#endif
+ }
+ }
+
+ if (zap) {
+ /*
+ * Wipe boodbits
+ */
+ char buf[1024];
+
+ if (lseek(fd, 0, SEEK_SET) != 0)
+ errx(EXIT_FAILURE, _("unable to rewind swap-device"));
+
+ memset(buf, 0, sizeof(buf));
+ if (write_all(fd, buf, sizeof(buf)))
+ errx(EXIT_FAILURE, _("unable to erase bootbits sectors"));
+#ifdef HAVE_LIBBLKID
+ /*
+ * Wipe rest of the device
+ */
+ if (!pr)
+ pr = new_prober(fd);
+
+ blkid_probe_enable_superblocks(pr, 1);
+ blkid_probe_enable_partitions(pr, 0);
+ blkid_probe_set_superblocks_flags(pr, BLKID_SUBLKS_MAGIC);
+
+ while (blkid_do_probe(pr) == 0)
+ blkid_do_wipe(pr, 0);
+#endif
+ } else {
+ warnx(_("%s: warning: don't erase bootbits sectors"),
+ devname);
+ if (type)
+ fprintf(stderr, _(" (%s partition table detected). "), type);
+ else if (whole)
+ fprintf(stderr, _(" on whole disk. "));
+ else
+ fprintf(stderr, _(" (compiled without libblkid). "));
+ fprintf(stderr, "Use -f to force.\n");
+ }
+#ifdef HAVE_LIBBLKID
+ blkid_free_probe(pr);
+#endif
+}
+
+int
+main(int argc, char **argv) {
+ struct stat statbuf;
+ struct swap_header_v1_2 *hdr;
+ int c;
+ unsigned long long maxpages;
+ unsigned long long goodpages;
+ unsigned long long sz;
+ off_t offset;
+ int force = 0;
+ int version = 1;
+ char *block_count = 0;
+ char *opt_label = NULL;
+ unsigned char *uuid = NULL;
+#ifdef HAVE_LIBUUID
+ const char *opt_uuid = NULL;
+ uuid_t uuid_dat;
+#endif
+ static const struct option longopts[] = {
+ { "check", no_argument, 0, 'c' },
+ { "force", no_argument, 0, 'f' },
+ { "pagesize", required_argument, 0, 'p' },
+ { "label", required_argument, 0, 'L' },
+ { "swapversion", required_argument, 0, 'v' },
+ { "uuid", required_argument, 0, 'U' },
+ { "version", no_argument, 0, 'V' },
+ { "help", no_argument, 0, 'h' },
+ { NULL, 0, 0, 0 }
+ };
+
+ setlocale(LC_ALL, "");
+ bindtextdomain(PACKAGE, LOCALEDIR);
+ textdomain(PACKAGE);
+ atexit(close_stdout);
+
+ while((c = getopt_long(argc, argv, "cfp:L:v:U:Vh", longopts, NULL)) != -1) {
+ switch (c) {
+ case 'c':
+ check=1;
+ break;
+ case 'f':
+ force=1;
+ break;
+ case 'p':
+ user_pagesize = strtou32_or_err(optarg, _("parse page size failed"));
+ break;
+ case 'L':
+ opt_label = optarg;
+ break;
+ case 'v':
+ version = strtos32_or_err(optarg, _("parse version number failed"));
+ break;
+ case 'U':
+#ifdef HAVE_LIBUUID
+ opt_uuid = optarg;
+#else
+ warnx(_("warning: ignore -U (UUIDs are unsupported by %s)"),
+ program_invocation_short_name);
+#endif
+ break;
+ case 'V':
+ printf(UTIL_LINUX_VERSION);
+ exit(EXIT_SUCCESS);
+ case 'h':
+ usage(stdout);
+ default:
+ usage(stderr);
+ }
+ }
+ if (optind < argc)
+ device_name = argv[optind++];
+ if (optind < argc)
+ block_count = argv[optind++];
+ if (optind != argc) {
+ warnx(("only one device as argument is currently supported."));
+ usage(stderr);
+ }
+
+ if (version != 1)
+ errx(EXIT_FAILURE,
+ _("does not support swapspace version %d."), version);
+
+#ifdef HAVE_LIBUUID
+ if(opt_uuid) {
+ if (uuid_parse(opt_uuid, uuid_dat) != 0)
+ errx(EXIT_FAILURE, _("error: UUID parsing failed"));
+ } else
+ uuid_generate(uuid_dat);
+ uuid = uuid_dat;
+#endif
+
+ init_signature_page(); /* get pagesize */
+
+ if (!device_name) {
+ warnx(_("error: Nowhere to set up swap on?"));
+ usage(stderr);
+ }
+ if (block_count) {
+ /* this silly user specified the number of blocks explicitly */
+ uint64_t blks = strtou64_or_err(block_count,
+ _("invalid block count argument"));
+ PAGES = blks / (pagesize / 1024);
+ }
+ sz = get_size(device_name);
+ if (!PAGES)
+ PAGES = sz;
+ else if (PAGES > sz && !force) {
+ errx(EXIT_FAILURE,
+ _("error: "
+ "size %llu KiB is larger than device size %llu KiB"),
+ PAGES*(pagesize/1024), sz*(pagesize/1024));
+ }
+
+ if (PAGES < MIN_GOODPAGES) {
+ warnx(_("error: swap area needs to be at least %ld KiB"),
+ (long)(MIN_GOODPAGES * pagesize/1024));
+ usage(stderr);
+ }
+
+#ifdef __linux__
+ if (get_linux_version() >= KERNEL_VERSION(2,3,4))
+ maxpages = UINT_MAX + 1ULL;
+ else if (get_linux_version() >= KERNEL_VERSION(2,2,1))
+ maxpages = V1_MAX_PAGES;
+ else
+#endif
+ maxpages = V1_OLD_MAX_PAGES;
+
+ if (PAGES > maxpages) {
+ PAGES = maxpages;
+ warnx(_("warning: truncating swap area to %llu KiB"),
+ PAGES * pagesize / 1024);
+ }
+
+ if (is_mounted(device_name))
+ errx(EXIT_FAILURE, _("error: "
+ "%s is mounted; will not make swapspace."),
+ device_name);
+
+ if (stat(device_name, &statbuf) < 0) {
+ perror(device_name);
+ exit(EXIT_FAILURE);
+ }
+ if (S_ISBLK(statbuf.st_mode))
+ DEV = open(device_name, O_RDWR | O_EXCL);
+ else
+ DEV = open(device_name, O_RDWR);
+
+ if (DEV < 0) {
+ perror(device_name);
+ exit(EXIT_FAILURE);
+ }
+
+ if (!S_ISBLK(statbuf.st_mode))
+ check=0;
+ else if (blkdev_is_misaligned(DEV))
+ warnx(_("warning: %s is misaligned"), device_name);
+
+ if (check)
+ check_blocks();
+
+ wipe_device(DEV, device_name, force, S_ISBLK(statbuf.st_mode));
+
+ hdr = (struct swap_header_v1_2 *) signature_page;
+ hdr->version = 1;
+ hdr->last_page = PAGES - 1;
+ hdr->nr_badpages = badpages;
+
+ if (badpages > PAGES - MIN_GOODPAGES)
+ errx(EXIT_FAILURE, _("Unable to set up swap-space: unreadable"));
+
+ goodpages = PAGES - badpages - 1;
+ printf(_("Setting up swapspace version 1, size = %llu KiB\n"),
+ goodpages * pagesize / 1024);
+
+ write_signature("SWAPSPACE2");
+ write_uuid_and_label(uuid, opt_label);
+
+ offset = 1024;
+ if (lseek(DEV, offset, SEEK_SET) != offset)
+ errx(EXIT_FAILURE, _("unable to rewind swap-device"));
+ if (write_all(DEV, (char *) signature_page + offset,
+ pagesize - offset) == -1)
+ err(EXIT_FAILURE,
+ _("%s: unable to write signature page"),
+ device_name);
+
+ /*
+ * A subsequent swapon() will fail if the signature
+ * is not actually on disk. (This is a kernel bug.)
+ */
+#ifdef HAVE_FSYNC
+ if (fsync(DEV))
+ errx(EXIT_FAILURE, _("fsync failed"));
+#endif
+
+#ifdef HAVE_LIBSELINUX
+ if (S_ISREG(statbuf.st_mode) && is_selinux_enabled() > 0) {
+ security_context_t context_string;
+ security_context_t oldcontext;
+ context_t newcontext;
+
+ if (fgetfilecon(DEV, &oldcontext) < 0) {
+ if (errno != ENODATA)
+ err(EXIT_FAILURE,
+ _("%s: unable to obtain selinux file label"),
+ device_name);
+ if (matchpathcon(device_name, statbuf.st_mode, &oldcontext))
+ errx(EXIT_FAILURE, _("unable to matchpathcon()"));
+ }
+ if (!(newcontext = context_new(oldcontext)))
+ errx(EXIT_FAILURE, _("unable to create new selinux context"));
+ if (context_type_set(newcontext, SELINUX_SWAPFILE_TYPE))
+ errx(EXIT_FAILURE, _("couldn't compute selinux context"));
+
+ context_string = context_str(newcontext);
+
+ if (strcmp(context_string, oldcontext)!=0) {
+ if (fsetfilecon(DEV, context_string))
+ err(EXIT_FAILURE, _("unable to relabel %s to %s"),
+ device_name, context_string);
+ }
+ context_free(newcontext);
+ freecon(oldcontext);
+ }
+#endif
+ return EXIT_SUCCESS;
+}
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