Imported from util-linux-2.9i tarball.

1 files changed, 212 insertions, 59 deletions

diff --git a/disk-utils/mkswap.c b/disk-utils/mkswap.c
index 49447f2af..b3402366c 100644
--- a/disk-utils/mkswap.c
+++ b/disk-utils/mkswap.c
@@ -8,15 +8,21 @@
 /*
  * 20.12.91  -	time began. Got VM working yesterday by doing this by hand.
  *
- * Usuage: mkswap [-c] device [size-in-blocks]
+ * Usuage: mkswap [-c] [-vN] [-f] device [size-in-blocks]
  *
- *	-c for readablility checking (use it unless you are SURE!)
+ *	-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 a image of one, but this isn't
+ * 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.
  */
 
 #include <stdio.h>
@@ -24,26 +30,85 @@
 #include <string.h>
 #include <fcntl.h>
 #include <stdlib.h>
-#include <sys/ioctl.h>
+#include <sys/ioctl.h>		/* for _IO */
+#include <sys/utsname.h>
 #include <sys/stat.h>
-#include <asm/page.h>
+#include <asm/page.h>		/* for PAGE_SIZE and PAGE_SHIFT */
 
+#ifndef _IO
+/* pre-1.3.45 */
 #define BLKGETSIZE 0x1260
-
-#ifndef __linux__
-# define volatile
+#else
+/* same on i386, m68k, arm; different on alpha, mips, sparc, ppc */
+#define BLKGETSIZE _IO(0x12,96)
 #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 int version = -1;
+
+#define MAKE_VERSION(p,q,r)	(65536*(p) + 256*(q) + (r))
+
+static int
+linux_version_code(void) {
+	struct utsname my_utsname;
+	int p, q, r;
+
+	if (uname(&my_utsname) == 0) {
+		p = atoi(strtok(my_utsname.release, "."));
+		q = atoi(strtok(NULL, "."));
+		r = atoi(strtok(NULL, "."));
+		return MAKE_VERSION(p,q,r);
+	}
+	return 0;
+}
+
+/*
+ * The definition of the union swap_header uses the constant PAGE_SIZE.
+ * Unfortunately, on some architectures this depends on the hardware model,
+ * and can only be found at run time -- we use getpagesize().
+ */
+
+static int pagesize;
+static int *signature_page;
 
-static int signature_page[PAGE_SIZE/sizeof(int)];
+struct swap_header_v1 {
+        char         bootbits[1024];    /* Space for disklabel etc. */
+	unsigned int version;
+	unsigned int last_page;
+	unsigned int nr_badpages;
+	unsigned int padding[125];
+	unsigned int badpages[1];
+} *p;
+
+static void
+init_signature_page() {
+	pagesize = getpagesize();
+
+#ifdef PAGE_SIZE
+	if (pagesize != PAGE_SIZE)
+		fprintf(stderr, "Assuming pages of size %d\n", pagesize);
+#endif
+	signature_page = (int *) malloc(pagesize);
+	memset(signature_page,0,pagesize);
+	p = (struct swap_header_v1 *) signature_page;
+}
+
+static void
+write_signature(char *sig) {
+	char *sp = (char *) signature_page;
+
+	strncpy(sp+pagesize-10, sig, 10);
+}
+
+#define V0_MAX_PAGES	(8 * (pagesize - 10))
+#define V1_MAX_PAGES	((0x7fffffff / pagesize) - 1)
+
+#define MAX_BADPAGES	((pagesize-1024-128*sizeof(int)-10)/sizeof(int))
 
 static void bit_set (unsigned int *addr, unsigned int nr)
 {
@@ -66,41 +131,56 @@ static int bit_test_and_clear (unsigned int *addr, unsigned int nr)
 	return (r & m) != 0;
 }
 
-/*
- * 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)
+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 usage() fatal_error("Usage: %s [-c] [-v0|-v1] /dev/name [blocks]\n")
 #define die(str) fatal_error("%s: " str "\n")
 
-void check_blocks(void)
-{
+void
+page_ok(int page) {
+	if (version==0)
+		bit_set(signature_page, page);
+}
+
+void
+page_bad(int page) {
+	if (version == 0)
+		bit_test_and_clear(signature_page, page);
+	else {
+		if (badpages == MAX_BADPAGES)
+			die("too many bad pages");
+		p->badpages[badpages] = page;
+	}
+	badpages++;
+}
+
+void
+check_blocks(void) {
 	unsigned int current_page;
 	int do_seek = 1;
-	static char buffer[PAGE_SIZE];
+	char *buffer;
 
+	buffer = malloc(pagesize);
+	if (!buffer)
+		die("Out of memory");
 	current_page = 0;
 	while (current_page < PAGES) {
 		if (!check) {
-			bit_set(signature_page,current_page++);
+			page_ok(current_page++);
 			continue;
 		}
-		if (do_seek && lseek(DEV,current_page*PAGE_SIZE,SEEK_SET) !=
-		current_page*PAGE_SIZE)
+		if (do_seek && lseek(DEV,current_page*pagesize,SEEK_SET) !=
+		    current_page*pagesize)
 			die("seek failed in check_blocks");
-		if ((do_seek = (PAGE_SIZE != read(DEV, buffer, PAGE_SIZE)))) {
-			bit_test_and_clear(signature_page,current_page++);
-			badpages++;
+		if ((do_seek = (pagesize != read(DEV, buffer, pagesize)))) {
+			page_bad(current_page++);
 			continue;
 		}
-		bit_set(signature_page,current_page++);
+		page_ok(current_page++);
 	}
 	if (badpages)
 		printf("%d bad page%s\n",badpages,(badpages>1)?"s":"");
@@ -117,12 +197,13 @@ static long valid_offset (int fd, int offset)
 	return 1;
 }
 
-static int count_blocks (int fd)
+static int
+find_size (int fd)
 {
-	int high, low;
+	unsigned int high, low;
 
 	low = 0;
-	for (high = 1; valid_offset (fd, high); high *= 2)
+	for (high = 1; high > 0 && valid_offset (fd, high); high *= 2)
 		low = high;
 	while (low < high - 1)
 	{
@@ -133,26 +214,27 @@ static int count_blocks (int fd)
 		else
 			high = mid;
 	}
-	valid_offset (fd, 0);
 	return (low + 1);
 }
 
-static int get_size(const char  *file)
+/* return size in pages, to avoid integer overflow */
+static int
+get_size(const char  *file)
 {
 	int	fd;
 	int	size;
 
-	fd = open(file, O_RDWR);
+	fd = open(file, O_RDONLY);
 	if (fd < 0) {
 		perror(file);
 		exit(1);
 	}
 	if (ioctl(fd, BLKGETSIZE, &size) >= 0) {
-		close(fd);
-		return (size * 512);
+		int sectors_per_page = pagesize/512;
+		size /= sectors_per_page;
+	} else {
+		size = find_size(fd) / pagesize;
 	}
-		
-	size = count_blocks(fd);
 	close(fd);
 	return size;
 }
@@ -161,28 +243,41 @@ int main(int argc, char ** argv)
 {
 	char * tmp;
 	struct stat statbuf;
+	int maxpages;
 	int goodpages;
+	int offset;
+	int force = 0;
 
-	memset(signature_page,0,PAGE_SIZE);
 	if (argc && *argv)
 		program_name = *argv;
+
+	init_signature_page();	/* get pagesize */
+
 	while (argc-- > 1) {
 		argv++;
-		if (argv[0][0] != '-')
+		if (argv[0][0] != '-') {
 			if (device_name) {
-				PAGES = strtol(argv[0],&tmp,0)>>(PAGE_SHIFT-10);
+				int blocks_per_page = pagesize/1024;
+				PAGES = strtol(argv[0],&tmp,0)/blocks_per_page;
 				if (*tmp)
 					usage();
 			} else
 				device_name = argv[0];
-		else while (*++argv[0])
-			switch (argv[0][0]) {
-				case 'c': check=1; break;
-				default: usage();
+		} else {
+			switch (argv[0][1]) {
+				case 'c':
+					check=1;
+					break;
+				case 'f':
+					force=1;
+					break;
+				case 'v':
+					version=atoi(argv[0]+2);
+					break;
+				default:
+					usage();
 			}
-	}
-	if (device_name && !PAGES) {
-		PAGES = get_size(device_name) / PAGE_SIZE;
+		}
 	}
 	if (!device_name) {
 		fprintf(stderr,
@@ -190,17 +285,38 @@ int main(int argc, char ** argv)
 			program_name);
 		usage();
 	}
+	if (!PAGES) {
+		PAGES = get_size(device_name);
+	}
+
+	if (version == -1) {
+		if (PAGES <= V0_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 * PAGE_SIZE / 1024));
+			program_name, (long)(10 * pagesize / 1024));
 		usage();
 	}
-	if (PAGES > 8 * (PAGE_SIZE - 10)) {
-		PAGES = 8 * (PAGE_SIZE - 10);
+	maxpages = ((version == 0) ? V0_MAX_PAGES : V1_MAX_PAGES);
+	if (PAGES > maxpages) {
+		PAGES = maxpages;
 		fprintf(stderr, "%s: warning: truncating swap area to %ldkB\n",
-			program_name, PAGES * PAGE_SIZE / 1024);
+			program_name, PAGES * pagesize / 1024);
 	}
+
 	DEV = open(device_name,O_RDWR);
 	if (DEV < 0 || fstat(DEV, &statbuf) < 0) {
 		perror(device_name);
@@ -210,19 +326,56 @@ int main(int argc, char ** argv)
 		check=0;
 	else if (statbuf.st_rdev == 0x0300 || statbuf.st_rdev == 0x0340)
 		die("Will not try to make swapdevice on '%s'");
-	check_blocks();
-	if (!bit_test_and_clear(signature_page,0))
+
+#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, size = %ld bytes\n",
-		(long)(goodpages*PAGE_SIZE));
-	strncpy((char*)signature_page+PAGE_SIZE-10, "SWAP-SPACE", 10);
-	if (lseek(DEV, 0, SEEK_SET))
+	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 (PAGE_SIZE != write(DEV, signature_page, PAGE_SIZE))
+	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.)