001-squashfs.patch

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+				if (!squashfs_get_cached_block(s, (char *)
+						inodep, block, offset,
+						sizeof(*inodep), &next_block,
+						&next_offset))
+					goto failed_read;
+
+			if ((i = squashfs_new_inode(s, inodeb)) == NULL)
+				goto failed_read1;
+
+			i->i_nlink = inodep->nlink;
+			i->i_mode |= (inodeb->inode_type ==
+					SQUASHFS_CHRDEV_TYPE) ?  S_IFCHR :
+					S_IFBLK;
+			init_special_inode(i, i->i_mode,
+					old_decode_dev(inodep->rdev));
+
+			TRACE("Device inode %x:%x, rdev %x\n",
+					SQUASHFS_INODE_BLK(inode), offset,
+					inodep->rdev);
+			break;
+		 }
+		 case SQUASHFS_FIFO_TYPE:
+		 case SQUASHFS_SOCKET_TYPE: {
+			struct squashfs_ipc_inode_header *inodep = &id.ipc;
+			struct squashfs_ipc_inode_header *sinodep = &sid.ipc;
+
+			if (msblk->swap) {
+				if (!squashfs_get_cached_block(s, (char *)
+						sinodep, block, offset,
+						sizeof(*sinodep), &next_block,
+						&next_offset))
+					goto failed_read;
+				SQUASHFS_SWAP_IPC_INODE_HEADER(inodep, sinodep);
+			} else
+				if (!squashfs_get_cached_block(s, (char *)
+						inodep, block, offset,
+						sizeof(*inodep), &next_block,
+						&next_offset))
+					goto failed_read;
+
+			if ((i = squashfs_new_inode(s, inodeb)) == NULL)
+				goto failed_read1;
+
+			i->i_nlink = inodep->nlink;
+			i->i_mode |= (inodeb->inode_type == SQUASHFS_FIFO_TYPE)
+							? S_IFIFO : S_IFSOCK;
+			init_special_inode(i, i->i_mode, 0);
+			break;
+		 }
+		 default:
+			ERROR("Unknown inode type %d in squashfs_iget!\n",
+					inodeb->inode_type);
+			goto failed_read1;
+	}
+
+	insert_inode_hash(i);
+	return i;
+
+failed_read:
+	ERROR("Unable to read inode [%llx:%x]\n", block, offset);
+
+failed_read1:
+	return NULL;
+}
+
+
+static int read_fragment_index_table(struct super_block *s)
+{
+	struct squashfs_sb_info *msblk = s->s_fs_info;
+	struct squashfs_super_block *sblk = &msblk->sblk;
+
+	/* Allocate fragment index table */
+	if (!(msblk->fragment_index = kmalloc(SQUASHFS_FRAGMENT_INDEX_BYTES
+					(sblk->fragments), GFP_KERNEL))) {
+		ERROR("Failed to allocate uid/gid table\n");
+		return 0;
+	}
+
+	if (SQUASHFS_FRAGMENT_INDEX_BYTES(sblk->fragments) &&
+					!squashfs_read_data(s, (char *)
+					msblk->fragment_index,
+					sblk->fragment_table_start,
+					SQUASHFS_FRAGMENT_INDEX_BYTES
+					(sblk->fragments) |
+					SQUASHFS_COMPRESSED_BIT_BLOCK, NULL)) {
+		ERROR("unable to read fragment index table\n");
+		return 0;
+	}
+
+	if (msblk->swap) {
+		int i;
+		long long fragment;
+
+		for (i = 0; i < SQUASHFS_FRAGMENT_INDEXES(sblk->fragments);
+									i++) {
+			SQUASHFS_SWAP_FRAGMENT_INDEXES((&fragment),
+						&msblk->fragment_index[i], 1);
+			msblk->fragment_index[i] = fragment;
+		}
+	}
+
+	return 1;
+}
+
+
+static int supported_squashfs_filesystem(struct squashfs_sb_info *msblk, int silent)
+{
+	struct squashfs_super_block *sblk = &msblk->sblk;
+
+	msblk->iget = squashfs_iget;
+	msblk->read_blocklist = read_blocklist;
+	msblk->read_fragment_index_table = read_fragment_index_table;
+
+	if (sblk->s_major == 1) {
+		if (!squashfs_1_0_supported(msblk)) {
+			SERROR("Major/Minor mismatch, Squashfs 1.0 filesystems "
+				"are unsupported\n");
+			SERROR("Please recompile with "
+				"Squashfs 1.0 support enabled\n");
+			return 0;
+		}
+	} else if (sblk->s_major == 2) {
+		if (!squashfs_2_0_supported(msblk)) {
+			SERROR("Major/Minor mismatch, Squashfs 2.0 filesystems "
+				"are unsupported\n");
+			SERROR("Please recompile with "
+				"Squashfs 2.0 support enabled\n");
+			return 0;
+		}
+	} else if(sblk->s_major != SQUASHFS_MAJOR || sblk->s_minor >
+			SQUASHFS_MINOR) {
+		SERROR("Major/Minor mismatch, trying to mount newer %d.%d "
+				"filesystem\n", sblk->s_major, sblk->s_minor);
+		SERROR("Please update your kernel\n");
+		return 0;
+	}
+
+	return 1;
+}
+
+
+static int squashfs_fill_super(struct super_block *s, void *data, int silent)
+{
+	struct squashfs_sb_info *msblk;
+	struct squashfs_super_block *sblk;
+	int i;
+	char b[BDEVNAME_SIZE];
+	struct inode *root;
+
+	TRACE("Entered squashfs_read_superblock\n");
+
+	if (!(s->s_fs_info = kmalloc(sizeof(struct squashfs_sb_info),
+						GFP_KERNEL))) {
+		ERROR("Failed to allocate superblock\n");
+		goto failure;
+	}
+	memset(s->s_fs_info, 0, sizeof(struct squashfs_sb_info));
+	msblk = s->s_fs_info;
+	sblk = &msblk->sblk;
+
+	msblk->devblksize = sb_min_blocksize(s, BLOCK_SIZE);
+	msblk->devblksize_log2 = ffz(~msblk->devblksize);
+
+	init_MUTEX(&msblk->read_data_mutex);
+	init_MUTEX(&msblk->read_page_mutex);
+	init_MUTEX(&msblk->block_cache_mutex);
+	init_MUTEX(&msblk->fragment_mutex);
+	init_MUTEX(&msblk->meta_index_mutex);
+
+	init_waitqueue_head(&msblk->waitq);
+	init_waitqueue_head(&msblk->fragment_wait_queue);
+
+	if (!squashfs_read_data(s, (char *) sblk, SQUASHFS_START,
+					sizeof(struct squashfs_super_block) |
+					SQUASHFS_COMPRESSED_BIT_BLOCK, NULL)) {
+		SERROR("unable to read superblock\n");
+		goto failed_mount;
+	}
+
+	/* Check it is a SQUASHFS superblock */
+	msblk->swap = 0;
+	if ((s->s_magic = sblk->s_magic) != SQUASHFS_MAGIC) {
+		if (sblk->s_magic == SQUASHFS_MAGIC_SWAP) {
+			struct squashfs_super_block ssblk;
+
+			WARNING("Mounting a different endian SQUASHFS "
+				"filesystem on %s\n", bdevname(s->s_bdev, b));
+
+			SQUASHFS_SWAP_SUPER_BLOCK(&ssblk, sblk);
+			memcpy(sblk, &ssblk, sizeof(struct squashfs_super_block));
+			msblk->swap = 1;
+		} else  {
+			SERROR("Can't find a SQUASHFS superblock on %s\n",
+							bdevname(s->s_bdev, b));
+			goto failed_mount;
+		}
+	}
+
+	/* Check the MAJOR & MINOR versions */
+	if(!supported_squashfs_filesystem(msblk, silent))
+		goto failed_mount;
+
+	TRACE("Found valid superblock on %s\n", bdevname(s->s_bdev, b));
+	TRACE("Inodes are %scompressed\n",
+					SQUASHFS_UNCOMPRESSED_INODES
+					(sblk->flags) ? "un" : "");
+	TRACE("Data is %scompressed\n",
+					SQUASHFS_UNCOMPRESSED_DATA(sblk->flags)
+					? "un" : "");
+	TRACE("Check data is %s present in the filesystem\n",
+					SQUASHFS_CHECK_DATA(sblk->flags) ?
+					"" : "not");
+	TRACE("Filesystem size %lld bytes\n", sblk->bytes_used);
+	TRACE("Block size %d\n", sblk->block_size);
+	TRACE("Number of inodes %d\n", sblk->inodes);
+	if (sblk->s_major > 1)
+		TRACE("Number of fragments %d\n", sblk->fragments);
+	TRACE("Number of uids %d\n", sblk->no_uids);
+	TRACE("Number of gids %d\n", sblk->no_guids);
+	TRACE("sblk->inode_table_start %llx\n", sblk->inode_table_start);
+	TRACE("sblk->directory_table_start %llx\n", sblk->directory_table_start);
+	if (sblk->s_major > 1)
+		TRACE("sblk->fragment_table_start %llx\n",
+					sblk->fragment_table_start);
+	TRACE("sblk->uid_start %llx\n", sblk->uid_start);
+
+	s->s_flags |= MS_RDONLY;
+	s->s_op = &squashfs_ops;
+
+	/* Init inode_table block pointer array */
+	if (!(msblk->block_cache = kmalloc(sizeof(struct squashfs_cache) *
+					SQUASHFS_CACHED_BLKS, GFP_KERNEL))) {
+		ERROR("Failed to allocate block cache\n");
+		goto failed_mount;
+	}
+
+	for (i = 0; i < SQUASHFS_CACHED_BLKS; i++)
+		msblk->block_cache[i].block = SQUASHFS_INVALID_BLK;
+
+	msblk->next_cache = 0;
+
+	/* Allocate read_data block */
+	msblk->read_size = (sblk->block_size < SQUASHFS_METADATA_SIZE) ?
+					SQUASHFS_METADATA_SIZE :
+					sblk->block_size;
+
+	if (!(msblk->read_data = kmalloc(msblk->read_size, GFP_KERNEL))) {
+		ERROR("Failed to allocate read_data block\n");
+		goto failed_mount;
+	}
+
+	/* Allocate read_page block */
+	if (!(msblk->read_page = kmalloc(sblk->block_size, GFP_KERNEL))) {
+		ERROR("Failed to allocate read_page block\n");
+		goto failed_mount;
+	}
+
+	/* Allocate uid and gid tables */
+	if (!(msblk->uid = kmalloc((sblk->no_uids + sblk->no_guids) *
+					sizeof(unsigned int), GFP_KERNEL))) {
+		ERROR("Failed to allocate uid/gid table\n");
+		goto failed_mount;
+	}
+	msblk->guid = msblk->uid + sblk->no_uids;
+
+	if (msblk->swap) {
+		unsigned int suid[sblk->no_uids + sblk->no_guids];
+
+		if (!squashfs_read_data(s, (char *) &suid, sblk->uid_start,
+					((sblk->no_uids + sblk->no_guids) *
+					 sizeof(unsigned int)) |
+					SQUASHFS_COMPRESSED_BIT_BLOCK, NULL)) {
+			ERROR("unable to read uid/gid table\n");
+			goto failed_mount;
+		}
+
+		SQUASHFS_SWAP_DATA(msblk->uid, suid, (sblk->no_uids +
+			sblk->no_guids), (sizeof(unsigned int) * 8));
+	} else
+		if (!squashfs_read_data(s, (char *) msblk->uid, sblk->uid_start,
+					((sblk->no_uids + sblk->no_guids) *
+					 sizeof(unsigned int)) |
+					SQUASHFS_COMPRESSED_BIT_BLOCK, NULL)) {
+			ERROR("unable to read uid/gid table\n");
+			goto failed_mount;
+		}
+
+
+	if (sblk->s_major == 1 && squashfs_1_0_supported(msblk))
+		goto allocate_root;
+
+	if (!(msblk->fragment = kmalloc(sizeof(struct squashfs_fragment_cache) *
+				SQUASHFS_CACHED_FRAGMENTS, GFP_KERNEL))) {
+		ERROR("Failed to allocate fragment block cache\n");
+		goto failed_mount;
+	}
+
+	for (i = 0; i < SQUASHFS_CACHED_FRAGMENTS; i++) {
+		msblk->fragment[i].locked = 0;
+		msblk->fragment[i].block = SQUASHFS_INVALID_BLK;
+		msblk->fragment[i].data = NULL;
+	}
+
+	msblk->next_fragment = 0;
+
+	/* Allocate fragment index table */
+	if (msblk->read_fragment_index_table(s) == 0)
+		goto failed_mount;
+
+allocate_root:
+	if ((root = (msblk->iget)(s, sblk->root_inode)) == NULL)
+		goto failed_mount;
+
+	if ((s->s_root = d_alloc_root(root)) == NULL) {
+		ERROR("Root inode create failed\n");
+		iput(root);
+		goto failed_mount;
+	}
+
+	TRACE("Leaving squashfs_read_super\n");
+	return 0;
+
+failed_mount:
+	kfree(msblk->fragment_index);
+	kfree(msblk->fragment);
+	kfree(msblk->uid);
+	kfree(msblk->read_page);
+	kfree(msblk->read_data);
+	kfree(msblk->block_cache);
+	kfree(msblk->fragment_index_2);
+	kfree(s->s_fs_info);
+	s->s_fs_info = NULL;
+	return -EINVAL;
+
+failure:
+	return -ENOMEM;
+}
+
+
+static int squashfs_statfs(struct dentry *dentry, struct kstatfs *buf)
+{
+	struct squashfs_sb_info *msblk = dentry->d_inode->i_sb->s_fs_info;
+	struct squashfs_super_block *sblk = &msblk->sblk;
+
+	TRACE("Entered squashfs_statfs\n");
+
+	buf->f_type = SQUASHFS_MAGIC;
+	buf->f_bsize = sblk->block_size;
+	buf->f_blocks = ((sblk->bytes_used - 1) >> sblk->block_log) + 1;
+	buf->f_bfree = buf->f_bavail = 0;
+	buf->f_files = sblk->inodes;
+	buf->f_ffree = 0;
+	buf->f_namelen = SQUASHFS_NAME_LEN;
+
+	return 0;
+}
+
+
+static int squashfs_symlink_readpage(struct file *file, struct page *page)
+{
+	struct inode *inode = page->mapping->host;
+	int index = page->index << PAGE_CACHE_SHIFT, length, bytes;
+	long long block = SQUASHFS_I(inode)->start_block;
+	int offset = SQUASHFS_I(inode)->offset;
+	void *pageaddr = kmap(page);
+
+	TRACE("Entered squashfs_symlink_readpage, page index %ld, start block "
+				"%llx, offset %x\n", page->index,
+				SQUASHFS_I(inode)->start_block,
+				SQUASHFS_I(inode)->offset);
+
+	for (length = 0; length < index; length += bytes) {
+		if (!(bytes = squashfs_get_cached_block(inode->i_sb, NULL,
+				block, offset, PAGE_CACHE_SIZE, &block,
+				&offset))) {
+			ERROR("Unable to read symbolic link [%llx:%x]\n", block,
+					offset);
+			goto skip_read;
+		}
+	}
+
+	if (length != index) {
+		ERROR("(squashfs_symlink_readpage) length != index\n");
+		bytes = 0;
+		goto skip_read;
+	}
+
+	bytes = (i_size_read(inode) - length) > PAGE_CACHE_SIZE ? PAGE_CACHE_SIZE :
+					i_size_read(inode) - length;
+
+	if (!(bytes = squashfs_get_cached_block(inode->i_sb, pageaddr, block,
+					offset, bytes, &block, &offset)))
+		ERROR("Unable to read symbolic link [%llx:%x]\n", block, offset);
+
+skip_read:
+	memset(pageaddr + bytes, 0, PAGE_CACHE_SIZE - bytes);
+	kunmap(page);
+	SetPageUptodate(page);
+	unlock_page(page);
+
+	return 0;
+}
+
+
+struct meta_index *locate_meta_index(struct inode *inode, int index, int offset)
+{
+	struct meta_index *meta = NULL;
+	struct squashfs_sb_info *msblk = inode->i_sb->s_fs_info;
+	int i;
+
+	down(&msblk->meta_index_mutex);
+
+	TRACE("locate_meta_index: index %d, offset %d\n", index, offset);
+
+	if(msblk->meta_index == NULL)
+		goto not_allocated;
+
+	for (i = 0; i < SQUASHFS_META_NUMBER; i ++)
+		if (msblk->meta_index[i].inode_number == inode->i_ino &&
+				msblk->meta_index[i].offset >= offset &&
+				msblk->meta_index[i].offset <= index &&
+				msblk->meta_index[i].locked == 0) {
+			TRACE("locate_meta_index: entry %d, offset %d\n", i,
+					msblk->meta_index[i].offset);
+			meta = &msblk->meta_index[i];
+			offset = meta->offset;
+		}
+
+	if (meta)
+		meta->locked = 1;
+
+not_allocated:
+	up(&msblk->meta_index_mutex);
+
+	return meta;
+}
+
+
+struct meta_index *empty_meta_index(struct inode *inode, int offset, int skip)
+{
+	struct squashfs_sb_info *msblk = inode->i_sb->s_fs_info;
+	struct meta_index *meta = NULL;
+	int i;
+
+	down(&msblk->meta_index_mutex);
+
+	TRACE("empty_meta_index: offset %d, skip %d\n", offset, skip);
+
+	if(msblk->meta_index == NULL) {
+		if (!(msblk->meta_index = kmalloc(sizeof(struct meta_index) *
+					SQUASHFS_META_NUMBER, GFP_KERNEL))) {