X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=arch%2Fum%2Fdrivers%2Fcow_user.c;fp=arch%2Fum%2Fdrivers%2Fcow_user.c;h=61951b721268f1c030279cff98b2a25213708ca8;hb=64ba3f394c830ec48a1c31b53dcae312c56f1604;hp=0ec4052db9c5bbb183714a44012ef07fc388b026;hpb=be1e6109ac94a859551f8e1774eb9a8469fe055c;p=linux-2.6.git

diff --git a/arch/um/drivers/cow_user.c b/arch/um/drivers/cow_user.c
index 0ec4052db..61951b721 100644
--- a/arch/um/drivers/cow_user.c
+++ b/arch/um/drivers/cow_user.c
@@ -17,34 +17,30 @@
 
 #define PATH_LEN_V1 256
 
-typedef __u32 time32_t;
-
 struct cow_header_v1 {
-	__s32 magic;
-	__s32 version;
+	int magic;
+	int version;
 	char backing_file[PATH_LEN_V1];
-	time32_t mtime;
+	time_t mtime;
 	__u64 size;
-	__s32 sectorsize;
-} __attribute__((packed));
+	int sectorsize;
+};
 
-/* Define PATH_LEN_V3 as the usual value of MAXPATHLEN, just hard-code it in
- * case other systems have different values for MAXPATHLEN.
- *
- * The same must hold for V2 - we want file format compatibility, not anything
- * else.
- */
-#define PATH_LEN_V3 4096
-#define PATH_LEN_V2 PATH_LEN_V3
+#define PATH_LEN_V2 MAXPATHLEN
 
 struct cow_header_v2 {
 	__u32 magic;
 	__u32 version;
 	char backing_file[PATH_LEN_V2];
-	time32_t mtime;
+	time_t mtime;
 	__u64 size;
-	__s32 sectorsize;
-} __attribute__((packed));
+	int sectorsize;
+};
+
+/* Define PATH_LEN_V3 as the usual value of MAXPATHLEN, just hard-code it in
+ * case other systems have different values for MAXPATHLEN
+ */
+#define PATH_LEN_V3 4096
 
 /* Changes from V2 -
  *	PATH_LEN_V3 as described above
@@ -70,15 +66,6 @@ struct cow_header_v2 {
  *	Fixed (finally!) the rounding bug
  */
 
-/* Until Dec2005, __attribute__((packed)) was left out from the below
- * definition, leading on 64-bit systems to 4 bytes of padding after mtime, to
- * align size to 8-byte alignment.  This shifted all fields above (no padding
- * was present on 32-bit, no other padding was added).
- *
- * However, this _can be detected_: it means that cow_format (always 0 until
- * now) is shifted onto the first 4 bytes of backing_file, where it is otherwise
- * impossible to find 4 zeros. -bb */
-
 struct cow_header_v3 {
 	__u32 magic;
 	__u32 version;
@@ -88,18 +75,6 @@ struct cow_header_v3 {
 	__u32 alignment;
 	__u32 cow_format;
 	char backing_file[PATH_LEN_V3];
-} __attribute__((packed));
-
-/* This is the broken layout used by some 64-bit binaries. */
-struct cow_header_v3_broken {
-	__u32 magic;
-	__u32 version;
-	__s64 mtime;
-	__u64 size;
-	__u32 sectorsize;
-	__u32 alignment;
-	__u32 cow_format;
-	char backing_file[PATH_LEN_V3];
 };
 
 /* COW format definitions - for now, we have only the usual COW bitmap */
@@ -109,7 +84,6 @@ union cow_header {
 	struct cow_header_v1 v1;
 	struct cow_header_v2 v2;
 	struct cow_header_v3 v3;
-	struct cow_header_v3_broken v3_b;
 };
 
 #define COW_MAGIC 0x4f4f4f4d  /* MOOO */
@@ -210,9 +184,8 @@ int write_cow_header(char *cow_file, int fd, char *backing_file,
 
 	err = -EINVAL;
 	if(strlen(backing_file) > sizeof(header->backing_file) - 1){
-		/* Below, %zd is for a size_t value */
 		cow_printf("Backing file name \"%s\" is too long - names are "
-			   "limited to %zd characters\n", backing_file,
+			   "limited to %d characters\n", backing_file,
 			   sizeof(header->backing_file) - 1);
 		goto out_free;
 	}
@@ -327,8 +300,7 @@ int read_cow_header(int (*reader)(__u64, char *, int, void *), void *arg,
 		*align_out = *sectorsize_out;
 		file = header->v2.backing_file;
 	}
-	/* This is very subtle - see above at union cow_header definition */
-	else if(version == 3 && (*((int*)header->v3.backing_file) != 0)){
+	else if(version == 3){
 		if(n < sizeof(header->v3)){
 			cow_printf("read_cow_header - failed to read V3 "
 				   "header\n");
@@ -338,43 +310,9 @@ int read_cow_header(int (*reader)(__u64, char *, int, void *), void *arg,
 		*size_out = ntohll(header->v3.size);
 		*sectorsize_out = ntohl(header->v3.sectorsize);
 		*align_out = ntohl(header->v3.alignment);
-		if (*align_out == 0) {
-			cow_printf("read_cow_header - invalid COW header, "
-				   "align == 0\n");
-		}
 		*bitmap_offset_out = ROUND_UP(sizeof(header->v3), *align_out);
 		file = header->v3.backing_file;
 	}
-	else if(version == 3){
-		cow_printf("read_cow_header - broken V3 file with"
-			   " 64-bit layout - recovering content.\n");
-
-		if(n < sizeof(header->v3_b)){
-			cow_printf("read_cow_header - failed to read V3 "
-				   "header\n");
-			goto out;
-		}
-
-		/* this was used until Dec2005 - 64bits are needed to represent
-		 * 2038+. I.e. we can safely do this truncating cast.
-		 *
-		 * Additionally, we must use ntohl() instead of ntohll(), since
-		 * the program used to use the former (tested - I got mtime
-		 * mismatch "0 vs whatever").
-		 *
-		 * Ever heard about bug-to-bug-compatibility ? ;-) */
-		*mtime_out = (time32_t) ntohl(header->v3_b.mtime);
-
-		*size_out = ntohll(header->v3_b.size);
-		*sectorsize_out = ntohl(header->v3_b.sectorsize);
-		*align_out = ntohl(header->v3_b.alignment);
-		if (*align_out == 0) {
-			cow_printf("read_cow_header - invalid COW header, "
-				   "align == 0\n");
-		}
-		*bitmap_offset_out = ROUND_UP(sizeof(header->v3_b), *align_out);
-		file = header->v3_b.backing_file;
-	}
 	else {
 		cow_printf("read_cow_header - invalid COW version\n");
 		goto out;