| /* |
| * cramfs.c |
| * |
| * Copyright (C) 1999 Linus Torvalds |
| * |
| * Copyright (C) 2000-2002 Transmeta Corporation |
| * |
| * Copyright (C) 2003 Kai-Uwe Bloem, |
| * Auerswald GmbH & Co KG, <linux-development@auerswald.de> |
| * - adapted from the www.tuxbox.org u-boot tree, added "ls" command |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License (Version 2) as |
| * published by the Free Software Foundation. |
| * |
| * Compressed ROM filesystem for Linux. |
| * |
| * TODO: |
| * add support for resolving symbolic links |
| */ |
| |
| /* |
| * These are the VFS interfaces to the compressed ROM filesystem. |
| * The actual compression is based on zlib, see the other files. |
| */ |
| |
| #include <common.h> |
| #include <malloc.h> |
| |
| #if (CONFIG_COMMANDS & CFG_CMD_JFFS2) |
| |
| #include <asm/byteorder.h> |
| #include <linux/stat.h> |
| #include <jffs2/jffs2.h> |
| #include <jffs2/load_kernel.h> |
| #include <cramfs/cramfs_fs.h> |
| |
| /* These two macros may change in future, to provide better st_ino |
| semantics. */ |
| #define CRAMINO(x) (CRAMFS_GET_OFFSET(x) ? CRAMFS_GET_OFFSET(x)<<2 : 1) |
| #define OFFSET(x) ((x)->i_ino) |
| |
| struct cramfs_super super; |
| |
| /* CPU address space offset calculation macro, struct part_info offset is |
| * device address space offset, so we need to shift it by a device start address. */ |
| extern flash_info_t flash_info[CFG_MAX_FLASH_BANKS]; |
| #define PART_OFFSET(x) (x->offset + flash_info[x->dev->id->num].start[0]) |
| |
| static int cramfs_read_super (struct part_info *info) |
| { |
| unsigned long root_offset; |
| |
| /* Read the first block and get the superblock from it */ |
| memcpy (&super, (void *) PART_OFFSET(info), sizeof (super)); |
| |
| /* Do sanity checks on the superblock */ |
| if (super.magic != CRAMFS_32 (CRAMFS_MAGIC)) { |
| /* check at 512 byte offset */ |
| memcpy (&super, (void *) PART_OFFSET(info) + 512, sizeof (super)); |
| if (super.magic != CRAMFS_32 (CRAMFS_MAGIC)) { |
| printf ("cramfs: wrong magic\n"); |
| return -1; |
| } |
| } |
| |
| /* flags is reused several times, so swab it once */ |
| super.flags = CRAMFS_32 (super.flags); |
| super.size = CRAMFS_32 (super.size); |
| |
| /* get feature flags first */ |
| if (super.flags & ~CRAMFS_SUPPORTED_FLAGS) { |
| printf ("cramfs: unsupported filesystem features\n"); |
| return -1; |
| } |
| |
| /* Check that the root inode is in a sane state */ |
| if (!S_ISDIR (CRAMFS_16 (super.root.mode))) { |
| printf ("cramfs: root is not a directory\n"); |
| return -1; |
| } |
| root_offset = CRAMFS_GET_OFFSET (&(super.root)) << 2; |
| if (root_offset == 0) { |
| printf ("cramfs: empty filesystem"); |
| } else if (!(super.flags & CRAMFS_FLAG_SHIFTED_ROOT_OFFSET) && |
| ((root_offset != sizeof (struct cramfs_super)) && |
| (root_offset != 512 + sizeof (struct cramfs_super)))) { |
| printf ("cramfs: bad root offset %lu\n", root_offset); |
| return -1; |
| } |
| |
| return 0; |
| } |
| |
| static unsigned long cramfs_resolve (unsigned long begin, unsigned long offset, |
| unsigned long size, int raw, |
| char *filename) |
| { |
| unsigned long inodeoffset = 0, nextoffset; |
| |
| while (inodeoffset < size) { |
| struct cramfs_inode *inode; |
| char *name; |
| int namelen; |
| |
| inode = (struct cramfs_inode *) (begin + offset + |
| inodeoffset); |
| |
| /* |
| * Namelengths on disk are shifted by two |
| * and the name padded out to 4-byte boundaries |
| * with zeroes. |
| */ |
| namelen = CRAMFS_GET_NAMELEN (inode) << 2; |
| name = (char *) inode + sizeof (struct cramfs_inode); |
| |
| nextoffset = |
| inodeoffset + sizeof (struct cramfs_inode) + namelen; |
| |
| for (;;) { |
| if (!namelen) |
| return -1; |
| if (name[namelen - 1]) |
| break; |
| namelen--; |
| } |
| |
| if (!strncmp (filename, name, namelen)) { |
| char *p = strtok (NULL, "/"); |
| |
| if (raw && (p == NULL || *p == '\0')) |
| return offset + inodeoffset; |
| |
| if (S_ISDIR (CRAMFS_16 (inode->mode))) { |
| return cramfs_resolve (begin, |
| CRAMFS_GET_OFFSET |
| (inode) << 2, |
| CRAMFS_24 (inode-> |
| size), raw, |
| p); |
| } else if (S_ISREG (CRAMFS_16 (inode->mode))) { |
| return offset + inodeoffset; |
| } else { |
| printf ("%*.*s: unsupported file type (%x)\n", |
| namelen, namelen, name, |
| CRAMFS_16 (inode->mode)); |
| return 0; |
| } |
| } |
| |
| inodeoffset = nextoffset; |
| } |
| |
| printf ("can't find corresponding entry\n"); |
| return 0; |
| } |
| |
| static int cramfs_uncompress (unsigned long begin, unsigned long offset, |
| unsigned long loadoffset) |
| { |
| struct cramfs_inode *inode = (struct cramfs_inode *) (begin + offset); |
| unsigned long *block_ptrs = (unsigned long *) |
| (begin + (CRAMFS_GET_OFFSET (inode) << 2)); |
| unsigned long curr_block = (CRAMFS_GET_OFFSET (inode) + |
| (((CRAMFS_24 (inode->size)) + |
| 4095) >> 12)) << 2; |
| int size, total_size = 0; |
| int i; |
| |
| cramfs_uncompress_init (); |
| |
| for (i = 0; i < ((CRAMFS_24 (inode->size) + 4095) >> 12); i++) { |
| size = cramfs_uncompress_block ((void *) loadoffset, |
| (void *) (begin + curr_block), |
| (CRAMFS_32 (block_ptrs[i]) - |
| curr_block)); |
| if (size < 0) |
| return size; |
| loadoffset += size; |
| total_size += size; |
| curr_block = CRAMFS_32 (block_ptrs[i]); |
| } |
| |
| cramfs_uncompress_exit (); |
| return total_size; |
| } |
| |
| int cramfs_load (char *loadoffset, struct part_info *info, char *filename) |
| { |
| unsigned long offset; |
| |
| if (cramfs_read_super (info)) |
| return -1; |
| |
| offset = cramfs_resolve (PART_OFFSET(info), |
| CRAMFS_GET_OFFSET (&(super.root)) << 2, |
| CRAMFS_24 (super.root.size), 0, |
| strtok (filename, "/")); |
| |
| if (offset <= 0) |
| return offset; |
| |
| return cramfs_uncompress (PART_OFFSET(info), offset, |
| (unsigned long) loadoffset); |
| } |
| |
| static int cramfs_list_inode (struct part_info *info, unsigned long offset) |
| { |
| struct cramfs_inode *inode = (struct cramfs_inode *) |
| (PART_OFFSET(info) + offset); |
| char *name, str[20]; |
| int namelen, nextoff; |
| |
| /* |
| * Namelengths on disk are shifted by two |
| * and the name padded out to 4-byte boundaries |
| * with zeroes. |
| */ |
| namelen = CRAMFS_GET_NAMELEN (inode) << 2; |
| name = (char *) inode + sizeof (struct cramfs_inode); |
| nextoff = namelen; |
| |
| for (;;) { |
| if (!namelen) |
| return namelen; |
| if (name[namelen - 1]) |
| break; |
| namelen--; |
| } |
| |
| printf (" %s %8d %*.*s", mkmodestr (CRAMFS_16 (inode->mode), str), |
| CRAMFS_24 (inode->size), namelen, namelen, name); |
| |
| if ((CRAMFS_16 (inode->mode) & S_IFMT) == S_IFLNK) { |
| /* symbolic link. |
| * Unpack the link target, trusting in the inode's size field. |
| */ |
| unsigned long size = CRAMFS_24 (inode->size); |
| char *link = malloc (size); |
| |
| if (link != NULL && cramfs_uncompress (PART_OFFSET(info), offset, |
| (unsigned long) link) |
| == size) |
| printf (" -> %*.*s\n", (int) size, (int) size, link); |
| else |
| printf (" [Error reading link]\n"); |
| if (link) |
| free (link); |
| } else |
| printf ("\n"); |
| |
| return nextoff; |
| } |
| |
| int cramfs_ls (struct part_info *info, char *filename) |
| { |
| struct cramfs_inode *inode; |
| unsigned long inodeoffset = 0, nextoffset; |
| unsigned long offset, size; |
| |
| if (cramfs_read_super (info)) |
| return -1; |
| |
| if (strlen (filename) == 0 || !strcmp (filename, "/")) { |
| /* Root directory. Use root inode in super block */ |
| offset = CRAMFS_GET_OFFSET (&(super.root)) << 2; |
| size = CRAMFS_24 (super.root.size); |
| } else { |
| /* Resolve the path */ |
| offset = cramfs_resolve (PART_OFFSET(info), |
| CRAMFS_GET_OFFSET (&(super.root)) << |
| 2, CRAMFS_24 (super.root.size), 1, |
| strtok (filename, "/")); |
| |
| if (offset <= 0) |
| return offset; |
| |
| /* Resolving was successful. Examine the inode */ |
| inode = (struct cramfs_inode *) (PART_OFFSET(info) + offset); |
| if (!S_ISDIR (CRAMFS_16 (inode->mode))) { |
| /* It's not a directory - list it, and that's that */ |
| return (cramfs_list_inode (info, offset) > 0); |
| } |
| |
| /* It's a directory. List files within */ |
| offset = CRAMFS_GET_OFFSET (inode) << 2; |
| size = CRAMFS_24 (inode->size); |
| } |
| |
| /* List the given directory */ |
| while (inodeoffset < size) { |
| inode = (struct cramfs_inode *) (PART_OFFSET(info) + offset + |
| inodeoffset); |
| |
| nextoffset = cramfs_list_inode (info, offset + inodeoffset); |
| if (nextoffset == 0) |
| break; |
| inodeoffset += sizeof (struct cramfs_inode) + nextoffset; |
| } |
| |
| return 1; |
| } |
| |
| int cramfs_info (struct part_info *info) |
| { |
| if (cramfs_read_super (info)) |
| return 0; |
| |
| printf ("size: 0x%x (%u)\n", super.size, super.size); |
| |
| if (super.flags != 0) { |
| printf ("flags:\n"); |
| if (super.flags & CRAMFS_FLAG_FSID_VERSION_2) |
| printf ("\tFSID version 2\n"); |
| if (super.flags & CRAMFS_FLAG_SORTED_DIRS) |
| printf ("\tsorted dirs\n"); |
| if (super.flags & CRAMFS_FLAG_HOLES) |
| printf ("\tholes\n"); |
| if (super.flags & CRAMFS_FLAG_SHIFTED_ROOT_OFFSET) |
| printf ("\tshifted root offset\n"); |
| } |
| |
| printf ("fsid:\n\tcrc: 0x%x\n\tedition: 0x%x\n", |
| super.fsid.crc, super.fsid.edition); |
| printf ("name: %16s\n", super.name); |
| |
| return 1; |
| } |
| |
| int cramfs_check (struct part_info *info) |
| { |
| struct cramfs_super *sb; |
| |
| if (info->dev->id->type != MTD_DEV_TYPE_NOR) |
| return 0; |
| |
| sb = (struct cramfs_super *) PART_OFFSET(info); |
| if (sb->magic != CRAMFS_32 (CRAMFS_MAGIC)) { |
| /* check at 512 byte offset */ |
| sb = (struct cramfs_super *) (PART_OFFSET(info) + 512); |
| if (sb->magic != CRAMFS_32 (CRAMFS_MAGIC)) |
| return 0; |
| } |
| return 1; |
| } |
| |
| #endif /* CFG_FS_CRAMFS */ |