| |
| #include <linux/kernel.h> |
| #include <linux/fs.h> |
| #include <linux/minix_fs.h> |
| #include <linux/ext2_fs.h> |
| #include <linux/romfs_fs.h> |
| #include <linux/cramfs_fs.h> |
| #include <linux/initrd.h> |
| #include <linux/string.h> |
| #include <linux/slab.h> |
| |
| #include "do_mounts.h" |
| #include "../fs/squashfs/squashfs_fs.h" |
| |
| #include <linux/decompress/generic.h> |
| |
| |
| int __initdata rd_prompt = 1;/* 1 = prompt for RAM disk, 0 = don't prompt */ |
| |
| static int __init prompt_ramdisk(char *str) |
| { |
| rd_prompt = simple_strtol(str,NULL,0) & 1; |
| return 1; |
| } |
| __setup("prompt_ramdisk=", prompt_ramdisk); |
| |
| int __initdata rd_image_start; /* starting block # of image */ |
| |
| static int __init ramdisk_start_setup(char *str) |
| { |
| rd_image_start = simple_strtol(str,NULL,0); |
| return 1; |
| } |
| __setup("ramdisk_start=", ramdisk_start_setup); |
| |
| static int __init crd_load(int in_fd, int out_fd, decompress_fn deco); |
| |
| /* |
| * This routine tries to find a RAM disk image to load, and returns the |
| * number of blocks to read for a non-compressed image, 0 if the image |
| * is a compressed image, and -1 if an image with the right magic |
| * numbers could not be found. |
| * |
| * We currently check for the following magic numbers: |
| * minix |
| * ext2 |
| * romfs |
| * cramfs |
| * squashfs |
| * gzip |
| */ |
| static int __init |
| identify_ramdisk_image(int fd, int start_block, decompress_fn *decompressor) |
| { |
| const int size = 512; |
| struct minix_super_block *minixsb; |
| struct ext2_super_block *ext2sb; |
| struct romfs_super_block *romfsb; |
| struct cramfs_super *cramfsb; |
| struct squashfs_super_block *squashfsb; |
| int nblocks = -1; |
| unsigned char *buf; |
| const char *compress_name; |
| |
| buf = kmalloc(size, GFP_KERNEL); |
| if (!buf) |
| return -ENOMEM; |
| |
| minixsb = (struct minix_super_block *) buf; |
| ext2sb = (struct ext2_super_block *) buf; |
| romfsb = (struct romfs_super_block *) buf; |
| cramfsb = (struct cramfs_super *) buf; |
| squashfsb = (struct squashfs_super_block *) buf; |
| memset(buf, 0xe5, size); |
| |
| /* |
| * Read block 0 to test for compressed kernel |
| */ |
| sys_lseek(fd, start_block * BLOCK_SIZE, 0); |
| sys_read(fd, buf, size); |
| |
| *decompressor = decompress_method(buf, size, &compress_name); |
| if (compress_name) { |
| printk(KERN_NOTICE "RAMDISK: %s image found at block %d\n", |
| compress_name, start_block); |
| if (!*decompressor) |
| printk(KERN_EMERG |
| "RAMDISK: %s decompressor not configured!\n", |
| compress_name); |
| nblocks = 0; |
| goto done; |
| } |
| |
| /* romfs is at block zero too */ |
| if (romfsb->word0 == ROMSB_WORD0 && |
| romfsb->word1 == ROMSB_WORD1) { |
| printk(KERN_NOTICE |
| "RAMDISK: romfs filesystem found at block %d\n", |
| start_block); |
| nblocks = (ntohl(romfsb->size)+BLOCK_SIZE-1)>>BLOCK_SIZE_BITS; |
| goto done; |
| } |
| |
| if (cramfsb->magic == CRAMFS_MAGIC) { |
| printk(KERN_NOTICE |
| "RAMDISK: cramfs filesystem found at block %d\n", |
| start_block); |
| nblocks = (cramfsb->size + BLOCK_SIZE - 1) >> BLOCK_SIZE_BITS; |
| goto done; |
| } |
| |
| /* squashfs is at block zero too */ |
| if (le32_to_cpu(squashfsb->s_magic) == SQUASHFS_MAGIC) { |
| printk(KERN_NOTICE |
| "RAMDISK: squashfs filesystem found at block %d\n", |
| start_block); |
| nblocks = (le64_to_cpu(squashfsb->bytes_used) + BLOCK_SIZE - 1) |
| >> BLOCK_SIZE_BITS; |
| goto done; |
| } |
| |
| /* |
| * Read 512 bytes further to check if cramfs is padded |
| */ |
| sys_lseek(fd, start_block * BLOCK_SIZE + 0x200, 0); |
| sys_read(fd, buf, size); |
| |
| if (cramfsb->magic == CRAMFS_MAGIC) { |
| printk(KERN_NOTICE |
| "RAMDISK: cramfs filesystem found at block %d\n", |
| start_block); |
| nblocks = (cramfsb->size + BLOCK_SIZE - 1) >> BLOCK_SIZE_BITS; |
| goto done; |
| } |
| |
| /* |
| * Read block 1 to test for minix and ext2 superblock |
| */ |
| sys_lseek(fd, (start_block+1) * BLOCK_SIZE, 0); |
| sys_read(fd, buf, size); |
| |
| /* Try minix */ |
| if (minixsb->s_magic == MINIX_SUPER_MAGIC || |
| minixsb->s_magic == MINIX_SUPER_MAGIC2) { |
| printk(KERN_NOTICE |
| "RAMDISK: Minix filesystem found at block %d\n", |
| start_block); |
| nblocks = minixsb->s_nzones << minixsb->s_log_zone_size; |
| goto done; |
| } |
| |
| /* Try ext2 */ |
| if (ext2sb->s_magic == cpu_to_le16(EXT2_SUPER_MAGIC)) { |
| printk(KERN_NOTICE |
| "RAMDISK: ext2 filesystem found at block %d\n", |
| start_block); |
| nblocks = le32_to_cpu(ext2sb->s_blocks_count) << |
| le32_to_cpu(ext2sb->s_log_block_size); |
| goto done; |
| } |
| |
| 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); |
| return nblocks; |
| } |
| |
| int __init rd_load_image(char *from) |
| { |
| int res = 0; |
| int in_fd, out_fd; |
| unsigned long rd_blocks, devblocks; |
| int nblocks, i, disk; |
| char *buf = NULL; |
| unsigned short rotate = 0; |
| decompress_fn decompressor = NULL; |
| #if !defined(CONFIG_S390) |
| char rotator[4] = { '|' , '/' , '-' , '\\' }; |
| #endif |
| |
| out_fd = sys_open((const char __user __force *) "/dev/ram", O_RDWR, 0); |
| if (out_fd < 0) |
| goto out; |
| |
| in_fd = sys_open(from, O_RDONLY, 0); |
| if (in_fd < 0) |
| goto noclose_input; |
| |
| nblocks = identify_ramdisk_image(in_fd, rd_image_start, &decompressor); |
| if (nblocks < 0) |
| goto done; |
| |
| if (nblocks == 0) { |
| if (crd_load(in_fd, out_fd, decompressor) == 0) |
| goto successful_load; |
| goto done; |
| } |
| |
| /* |
| * NOTE NOTE: nblocks is not actually blocks but |
| * the number of kibibytes of data to load into a ramdisk. |
| * So any ramdisk block size that is a multiple of 1KiB should |
| * work when the appropriate ramdisk_blocksize is specified |
| * on the command line. |
| * |
| * The default ramdisk_blocksize is 1KiB and it is generally |
| * silly to use anything else, so make sure to use 1KiB |
| * blocksize while generating ext2fs ramdisk-images. |
| */ |
| if (sys_ioctl(out_fd, BLKGETSIZE, (unsigned long)&rd_blocks) < 0) |
| rd_blocks = 0; |
| else |
| rd_blocks >>= 1; |
| |
| if (nblocks > rd_blocks) { |
| printk("RAMDISK: image too big! (%dKiB/%ldKiB)\n", |
| nblocks, rd_blocks); |
| goto done; |
| } |
| |
| /* |
| * OK, time to copy in the data |
| */ |
| if (sys_ioctl(in_fd, BLKGETSIZE, (unsigned long)&devblocks) < 0) |
| devblocks = 0; |
| else |
| devblocks >>= 1; |
| |
| if (strcmp(from, "/initrd.image") == 0) |
| devblocks = nblocks; |
| |
| if (devblocks == 0) { |
| printk(KERN_ERR "RAMDISK: could not determine device size\n"); |
| goto done; |
| } |
| |
| buf = kmalloc(BLOCK_SIZE, GFP_KERNEL); |
| if (!buf) { |
| printk(KERN_ERR "RAMDISK: could not allocate buffer\n"); |
| goto done; |
| } |
| |
| printk(KERN_NOTICE "RAMDISK: Loading %dKiB [%ld disk%s] into ram disk... ", |
| nblocks, ((nblocks-1)/devblocks)+1, nblocks>devblocks ? "s" : ""); |
| for (i = 0, disk = 1; i < nblocks; i++) { |
| if (i && (i % devblocks == 0)) { |
| printk("done disk #%d.\n", disk++); |
| rotate = 0; |
| if (sys_close(in_fd)) { |
| printk("Error closing the disk.\n"); |
| goto noclose_input; |
| } |
| change_floppy("disk #%d", disk); |
| in_fd = sys_open(from, O_RDONLY, 0); |
| if (in_fd < 0) { |
| printk("Error opening disk.\n"); |
| goto noclose_input; |
| } |
| printk("Loading disk #%d... ", disk); |
| } |
| sys_read(in_fd, buf, BLOCK_SIZE); |
| sys_write(out_fd, buf, BLOCK_SIZE); |
| #if !defined(CONFIG_S390) |
| if (!(i % 16)) { |
| printk("%c\b", rotator[rotate & 0x3]); |
| rotate++; |
| } |
| #endif |
| } |
| printk("done.\n"); |
| |
| successful_load: |
| res = 1; |
| done: |
| sys_close(in_fd); |
| noclose_input: |
| sys_close(out_fd); |
| out: |
| kfree(buf); |
| sys_unlink((const char __user __force *) "/dev/ram"); |
| return res; |
| } |
| |
| int __init rd_load_disk(int n) |
| { |
| if (rd_prompt) |
| change_floppy("root floppy disk to be loaded into RAM disk"); |
| create_dev("/dev/root", ROOT_DEV); |
| create_dev("/dev/ram", MKDEV(RAMDISK_MAJOR, n)); |
| return rd_load_image("/dev/root"); |
| } |
| |
| static int exit_code; |
| static int decompress_error; |
| static int crd_infd, crd_outfd; |
| |
| static int __init compr_fill(void *buf, unsigned int len) |
| { |
| int r = sys_read(crd_infd, buf, len); |
| if (r < 0) |
| printk(KERN_ERR "RAMDISK: error while reading compressed data"); |
| else if (r == 0) |
| printk(KERN_ERR "RAMDISK: EOF while reading compressed data"); |
| return r; |
| } |
| |
| static int __init compr_flush(void *window, unsigned int outcnt) |
| { |
| int written = sys_write(crd_outfd, window, outcnt); |
| if (written != outcnt) { |
| if (decompress_error == 0) |
| printk(KERN_ERR |
| "RAMDISK: incomplete write (%d != %d)\n", |
| written, outcnt); |
| decompress_error = 1; |
| return -1; |
| } |
| return outcnt; |
| } |
| |
| static void __init error(char *x) |
| { |
| printk(KERN_ERR "%s\n", x); |
| exit_code = 1; |
| decompress_error = 1; |
| } |
| |
| static int __init crd_load(int in_fd, int out_fd, decompress_fn deco) |
| { |
| int result; |
| crd_infd = in_fd; |
| crd_outfd = out_fd; |
| result = deco(NULL, 0, compr_fill, compr_flush, NULL, NULL, error); |
| if (decompress_error) |
| result = 1; |
| return result; |
| } |