diff options
| -rw-r--r-- | init/do_mounts_rd.c | 82 |
1 files changed, 35 insertions, 47 deletions
diff --git a/init/do_mounts_rd.c b/init/do_mounts_rd.c index dcaeb1f90b3..9c9d7dbcf9c 100644 --- a/init/do_mounts_rd.c +++ b/init/do_mounts_rd.c @@ -43,13 +43,31 @@ static int __init crd_load(int in_fd, int out_fd, decompress_fn deco); * numbers could not be found. * * We currently check for the following magic numbers: - * minix - * ext2 + * minix + * ext2 * romfs * cramfs - * gzip + * gzip */ -static int __init +static const struct compress_format { + unsigned char magic[2]; + const char *name; + decompress_fn decompressor; +} compressed_formats[] = { +#ifdef CONFIG_RD_GZIP + { {037, 0213}, "gzip", gunzip }, + { {037, 0236}, "gzip", gunzip }, +#endif +#ifdef CONFIG_RD_BZIP2 + { {0x42, 0x5a}, "bzip2", bunzip2 }, +#endif +#ifdef CONFIG_RD_LZMA + { {0x5d, 0x00}, "lzma", unlzma }, +#endif + { {0, 0}, NULL, NULL } +}; + +static int __init identify_ramdisk_image(int fd, int start_block, decompress_fn *decompressor) { const int size = 512; @@ -59,6 +77,7 @@ identify_ramdisk_image(int fd, int start_block, decompress_fn *decompressor) struct cramfs_super *cramfsb; int nblocks = -1; unsigned char *buf; + const struct compress_format *cf; buf = kmalloc(size, GFP_KERNEL); if (!buf) @@ -71,52 +90,21 @@ identify_ramdisk_image(int fd, int start_block, decompress_fn *decompressor) memset(buf, 0xe5, size); /* - * Read block 0 to test for gzipped kernel + * Read block 0 to test for compressed kernel */ sys_lseek(fd, start_block * BLOCK_SIZE, 0); sys_read(fd, buf, size); -#ifdef CONFIG_RD_GZIP - /* - * If it matches the gzip magic numbers, return 0 - */ - if (buf[0] == 037 && ((buf[1] == 0213) || (buf[1] == 0236))) { - printk(KERN_NOTICE - "RAMDISK: Compressed image found at block %d\n", - start_block); - *decompressor = gunzip; - nblocks = 0; - goto done; - } -#endif - -#ifdef CONFIG_RD_BZIP2 - /* - * If it matches the bzip2 magic numbers, return -1 - */ - if (buf[0] == 0x42 && (buf[1] == 0x5a)) { - printk(KERN_NOTICE - "RAMDISK: Bzipped image found at block %d\n", - start_block); - *decompressor = bunzip2; - nblocks = 0; - goto done; - } -#endif - -#ifdef CONFIG_RD_LZMA - /* - * If it matches the lzma magic numbers, return -1 - */ - if (buf[0] == 0x5d && (buf[1] == 0x00)) { - printk(KERN_NOTICE - "RAMDISK: Lzma image found at block %d\n", - start_block); - *decompressor = unlzma; - nblocks = 0; - goto done; + for (cf = compressed_formats; cf->decompressor; cf++) { + if (buf[0] == cf->magic[0] && buf[1] == cf->magic[1]) { + printk(KERN_NOTICE + "RAMDISK: %s image found at block %d\n", + cf->name, start_block); + *decompressor = cf->decompressor; + nblocks = 0; + goto done; + } } -#endif /* romfs is at block zero too */ if (romfsb->word0 == ROMSB_WORD0 && @@ -165,7 +153,7 @@ identify_ramdisk_image(int fd, int start_block, decompress_fn *decompressor) printk(KERN_NOTICE "RAMDISK: Couldn't find valid RAM disk image starting at %d.\n", start_block); - + done: sys_lseek(fd, start_block * BLOCK_SIZE, 0); kfree(buf); @@ -224,7 +212,7 @@ int __init rd_load_image(char *from) nblocks, rd_blocks); goto done; } - + /* * OK, time to copy in the data */ |