[PATCH v2 3/3] fs: add support for SquashFS 4.0
yegorslists at googlemail.com
yegorslists at googlemail.com
Tue Feb 16 00:23:17 PST 2016
From: Yegor Yefremov <yegorslists at googlemail.com>
The driver was imported from Linux 4.4.
Signed-off-by: Yegor Yefremov <yegorslists at googlemail.com>
---
Changes:
v2: - fix checkpatch errors
- remove spinlock/wait code from cache implementation
- fix directory listing
- add documentation entry about SquashFS
- fix compiling without XZ enabled
- fix some memory leaks
Documentation/filesystems/squashfs.rst | 15 ++
fs/Kconfig | 1 +
fs/Makefile | 1 +
fs/squashfs/Kconfig | 31 +++
fs/squashfs/Makefile | 13 +
fs/squashfs/block.c | 212 +++++++++++++++
fs/squashfs/cache.c | 393 ++++++++++++++++++++++++++++
fs/squashfs/decompressor.c | 140 ++++++++++
fs/squashfs/decompressor.h | 57 ++++
fs/squashfs/decompressor_single.c | 83 ++++++
fs/squashfs/file.c | 460 +++++++++++++++++++++++++++++++++
fs/squashfs/file_cache.c | 35 +++
fs/squashfs/fragment.c | 94 +++++++
fs/squashfs/id.c | 98 +++++++
fs/squashfs/inode.c | 402 ++++++++++++++++++++++++++++
fs/squashfs/namei.c | 381 +++++++++++++++++++++++++++
fs/squashfs/page_actor.c | 99 +++++++
fs/squashfs/page_actor.h | 53 ++++
fs/squashfs/squashfs.c | 356 +++++++++++++++++++++++++
fs/squashfs/squashfs.h | 138 ++++++++++
fs/squashfs/squashfs_fs.h | 453 ++++++++++++++++++++++++++++++++
fs/squashfs/squashfs_fs_i.h | 52 ++++
fs/squashfs/squashfs_fs_sb.h | 82 ++++++
fs/squashfs/super.c | 348 +++++++++++++++++++++++++
fs/squashfs/xz_wrapper.c | 190 ++++++++++++++
25 files changed, 4187 insertions(+)
create mode 100644 Documentation/filesystems/squashfs.rst
create mode 100644 fs/squashfs/Kconfig
create mode 100644 fs/squashfs/Makefile
create mode 100644 fs/squashfs/block.c
create mode 100644 fs/squashfs/cache.c
create mode 100644 fs/squashfs/decompressor.c
create mode 100644 fs/squashfs/decompressor.h
create mode 100644 fs/squashfs/decompressor_single.c
create mode 100644 fs/squashfs/file.c
create mode 100644 fs/squashfs/file_cache.c
create mode 100644 fs/squashfs/fragment.c
create mode 100644 fs/squashfs/id.c
create mode 100644 fs/squashfs/inode.c
create mode 100644 fs/squashfs/namei.c
create mode 100644 fs/squashfs/page_actor.c
create mode 100644 fs/squashfs/page_actor.h
create mode 100644 fs/squashfs/squashfs.c
create mode 100644 fs/squashfs/squashfs.h
create mode 100644 fs/squashfs/squashfs_fs.h
create mode 100644 fs/squashfs/squashfs_fs_i.h
create mode 100644 fs/squashfs/squashfs_fs_sb.h
create mode 100644 fs/squashfs/super.c
create mode 100644 fs/squashfs/xz_wrapper.c
diff --git a/Documentation/filesystems/squashfs.rst b/Documentation/filesystems/squashfs.rst
new file mode 100644
index 0000000..be82973
--- /dev/null
+++ b/Documentation/filesystems/squashfs.rst
@@ -0,0 +1,15 @@
+.. index:: squashfs (filesystem)
+
+SquashFS filesystem
+===================
+
+SquashFS is a highly compressed read-only filesystem for Linux.
+It uses zlib, lzo or xz compression to compress both files, inodes
+and directories. A SquashFS filesystem can be mounted using the
+:ref:`command_mount` command::
+
+ mkdir /mnt
+ mount -t squashfs /dev/spiflash.FileSystem /mnt
+ ls /mnt
+ zImage barebox.bin
+ umount /mnt
diff --git a/fs/Kconfig b/fs/Kconfig
index 56fe41a..c7c42ac 100644
--- a/fs/Kconfig
+++ b/fs/Kconfig
@@ -90,6 +90,7 @@ config FS_SMHFS
Barebox
source fs/pstore/Kconfig
+source fs/squashfs/Kconfig
config FS_RATP
bool
diff --git a/fs/Makefile b/fs/Makefile
index 7896e38..e245a8f 100644
--- a/fs/Makefile
+++ b/fs/Makefile
@@ -16,3 +16,4 @@ obj-$(CONFIG_FS_EFIVARFS) += efivarfs.o
obj-$(CONFIG_FS_SMHFS) += smhfs.o
obj-$(CONFIG_FS_PSTORE) += pstore/
obj-$(CONFIG_FS_RATP) += ratpfs.o
+obj-$(CONFIG_FS_SQUASHFS) += squashfs/
diff --git a/fs/squashfs/Kconfig b/fs/squashfs/Kconfig
new file mode 100644
index 0000000..d8836d5
--- /dev/null
+++ b/fs/squashfs/Kconfig
@@ -0,0 +1,31 @@
+menuconfig FS_SQUASHFS
+ bool
+ prompt "squashfs support"
+ help
+ Saying Y here includes support for SquashFS 4.0 (a Compressed
+ Read-Only File System). Squashfs is a highly compressed read-only
+ filesystem for Linux. It uses zlib, lzo or xz compression to
+ compress both files, inodes and directories. Inodes in the system
+ are very small and all blocks are packed to minimise data overhead.
+ Block sizes greater than 4K are supported up to a maximum of 1 Mbytes
+ (default block size 128K). SquashFS 4.0 supports 64 bit filesystems
+ and files (larger than 4GB), full uid/gid information, hard links and
+ timestamps.
+
+ Squashfs is intended for general read-only filesystem use, for
+ archival use (i.e. in cases where a .tar.gz file may be used), and in
+ embedded systems where low overhead is needed. Further information
+ and tools are available from http://squashfs.sourceforge.net.
+
+config SQUASHFS_XZ
+ bool "Include support for XZ compressed file systems"
+ depends on FS_SQUASHFS
+ select XZ_DECOMPRESS
+ help
+ Saying Y here includes support for reading Squashfs file systems
+ compressed with XZ compression. XZ gives better compression than
+ the default zlib compression, at the expense of greater CPU and
+ memory overhead.
+
+ XZ is not the standard compression used in Squashfs and so most
+ file systems will be readable without selecting this option.
diff --git a/fs/squashfs/Makefile b/fs/squashfs/Makefile
new file mode 100644
index 0000000..c0d024c
--- /dev/null
+++ b/fs/squashfs/Makefile
@@ -0,0 +1,13 @@
+obj-y += squashfs.o
+obj-y += block.o
+obj-y += cache.o
+obj-y += decompressor.o
+obj-y += decompressor_single.o
+obj-y += file.o
+obj-y += file_cache.o
+obj-y += fragment.o
+obj-y += id.o
+obj-y += inode.o
+obj-y += namei.o
+obj-y += super.o
+obj-$(CONFIG_SQUASHFS_XZ) += xz_wrapper.o
diff --git a/fs/squashfs/block.c b/fs/squashfs/block.c
new file mode 100644
index 0000000..3e2b9a5
--- /dev/null
+++ b/fs/squashfs/block.c
@@ -0,0 +1,212 @@
+/*
+ * Squashfs - a compressed read only filesystem for Linux
+ *
+ * Copyright (c) 2002, 2003, 2004, 2005, 2006, 2007, 2008
+ * Phillip Lougher <phillip at squashfs.org.uk>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2,
+ * or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * block.c
+ */
+
+/*
+ * This file implements the low-level routines to read and decompress
+ * datablocks and metadata blocks.
+ */
+
+#include <linux/fs.h>
+#include <linux/string.h>
+
+#include "squashfs_fs.h"
+#include "squashfs_fs_sb.h"
+#include "squashfs.h"
+#include "decompressor.h"
+#include "page_actor.h"
+
+/*
+ * Read the metadata block length, this is stored in the first two
+ * bytes of the metadata block.
+ */
+static char *get_block_length(struct super_block *sb,
+ u64 *cur_index, int *offset, int *length)
+{
+ struct squashfs_sb_info *msblk = sb->s_fs_info;
+ char *buf;
+
+ buf = squashfs_devread(msblk,
+ *cur_index * msblk->devblksize,
+ msblk->devblksize);
+ if (buf == NULL)
+ return NULL;
+
+ if (msblk->devblksize - *offset == 1) {
+ *length = (unsigned char) buf[*offset];
+ free(buf);
+ buf = squashfs_devread(msblk,
+ ++(*cur_index) * msblk->devblksize,
+ msblk->devblksize);
+ if (buf == NULL)
+ return NULL;
+ *length |= (unsigned char) buf[0] << 8;
+ *offset = 1;
+ } else {
+ *length = (unsigned char) buf[*offset] |
+ (unsigned char) buf[*offset + 1] << 8;
+ *offset += 2;
+
+ if (*offset == msblk->devblksize) {
+ free(buf);
+ buf = squashfs_devread(msblk,
+ ++(*cur_index) * msblk->devblksize,
+ msblk->devblksize);
+ if (buf == NULL)
+ return NULL;
+ *offset = 0;
+ }
+ }
+
+ return buf;
+}
+
+
+/*
+ * Read and decompress a metadata block or datablock. Length is non-zero
+ * if a datablock is being read (the size is stored elsewhere in the
+ * filesystem), otherwise the length is obtained from the first two bytes of
+ * the metadata block. A bit in the length field indicates if the block
+ * is stored uncompressed in the filesystem (usually because compression
+ * generated a larger block - this does occasionally happen with compression
+ * algorithms).
+ */
+int squashfs_read_data(struct super_block *sb, u64 index, int length,
+ u64 *next_index, struct squashfs_page_actor *output)
+{
+ struct squashfs_sb_info *msblk = sb->s_fs_info;
+ char **buf;
+ int offset = index & ((1 << msblk->devblksize_log2) - 1);
+ u64 cur_index = index >> msblk->devblksize_log2;
+ int bytes, compressed, b = 0, k = 0, avail;
+
+ buf = calloc(((output->length + msblk->devblksize - 1)
+ >> msblk->devblksize_log2) + 1, sizeof(*buf));
+ if (buf == NULL)
+ return -ENOMEM;
+
+ if (length) {
+ /*
+ * Datablock.
+ */
+ bytes = -offset;
+ compressed = SQUASHFS_COMPRESSED_BLOCK(length);
+ length = SQUASHFS_COMPRESSED_SIZE_BLOCK(length);
+ if (next_index)
+ *next_index = index + length;
+
+ TRACE("Block @ 0x%llx, %scompressed size %d, src size %d\n",
+ index, compressed ? "" : "un", length, output->length);
+
+ if (length < 0 || length > output->length ||
+ (index + length) > msblk->bytes_used) {
+ goto read_failure;
+ }
+
+ for (b = 0; bytes < length; b++, cur_index++) {
+ buf[b] = squashfs_devread(msblk,
+ cur_index * msblk->devblksize,
+ msblk->devblksize);
+ if (buf[b] == NULL)
+ goto block_release;
+
+ bytes += msblk->devblksize;
+ }
+
+ } else {
+ /*
+ * Metadata block.
+ */
+ if ((index + 2) > msblk->bytes_used)
+ goto read_failure;
+
+ buf[0] = get_block_length(sb, &cur_index, &offset, &length);
+ if (buf[0] == NULL)
+ goto read_failure;
+ b = 1;
+
+ bytes = msblk->devblksize - offset;
+ compressed = SQUASHFS_COMPRESSED(length);
+ length = SQUASHFS_COMPRESSED_SIZE(length);
+ if (next_index)
+ *next_index = index + length + 2;
+
+ TRACE("Block Meta @ 0x%llx, %scompressed size %d\n", index,
+ compressed ? "" : "un", length);
+
+ if (length < 0 || length > output->length ||
+ (index + length) > msblk->bytes_used)
+ goto block_release;
+
+ for (; bytes < length; b++) {
+ buf[b] = squashfs_devread(msblk,
+ ++cur_index * msblk->devblksize,
+ msblk->devblksize);
+ if (buf[b] == NULL)
+ goto block_release;
+ bytes += msblk->devblksize;
+ }
+ }
+
+ if (compressed) {
+ length = squashfs_decompress(msblk, buf, b, offset, length,
+ output);
+ if (length < 0)
+ goto read_failure;
+ } else {
+ /*
+ * Block is uncompressed.
+ */
+ int pg_offset = 0;
+ void *data = squashfs_first_page(output);
+
+ for (bytes = length; k < b; k++) {
+ int in = min(bytes, msblk->devblksize - offset);
+ bytes -= in;
+ while (in) {
+ if (pg_offset == PAGE_CACHE_SIZE) {
+ data = squashfs_next_page(output);
+ pg_offset = 0;
+ }
+ avail = min_t(int, in, PAGE_CACHE_SIZE -
+ pg_offset);
+ memcpy(data + pg_offset, buf[k] + offset,
+ avail);
+ in -= avail;
+ pg_offset += avail;
+ offset += avail;
+ }
+ offset = 0;
+ kfree(buf[k]);
+ }
+ squashfs_finish_page(output);
+ }
+
+ kfree(buf);
+ return length;
+
+block_release:
+ for (; k < b; k++)
+ kfree(buf[k]);
+
+read_failure:
+ ERROR("squashfs_read_data failed to read block 0x%llx\n",
+ (unsigned long long) index);
+ kfree(buf);
+ return -EIO;
+}
diff --git a/fs/squashfs/cache.c b/fs/squashfs/cache.c
new file mode 100644
index 0000000..766bc99
--- /dev/null
+++ b/fs/squashfs/cache.c
@@ -0,0 +1,393 @@
+/*
+ * Squashfs - a compressed read only filesystem for Linux
+ *
+ * Copyright (c) 2002, 2003, 2004, 2005, 2006, 2007, 2008
+ * Phillip Lougher <phillip at squashfs.org.uk>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2,
+ * or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * cache.c
+ */
+
+/*
+ * Blocks in Squashfs are compressed. To avoid repeatedly decompressing
+ * recently accessed data Squashfs uses two small metadata and fragment caches.
+ *
+ * This file implements a generic cache implementation used for both caches,
+ * plus functions layered ontop of the generic cache implementation to
+ * access the metadata and fragment caches.
+ *
+ * To avoid out of memory and fragmentation issues with vmalloc the cache
+ * uses sequences of kmalloced PAGE_CACHE_SIZE buffers.
+ *
+ * It should be noted that the cache is not used for file datablocks, these
+ * are decompressed and cached in the page-cache in the normal way. The
+ * cache is only used to temporarily cache fragment and metadata blocks
+ * which have been read as as a result of a metadata (i.e. inode or
+ * directory) or fragment access. Because metadata and fragments are packed
+ * together into blocks (to gain greater compression) the read of a particular
+ * piece of metadata or fragment will retrieve other metadata/fragments which
+ * have been packed with it, these because of locality-of-reference may be read
+ * in the near future. Temporarily caching them ensures they are available for
+ * near future access without requiring an additional read and decompress.
+ */
+
+#include <linux/fs.h>
+#include <linux/pagemap.h>
+
+#include "squashfs_fs.h"
+#include "squashfs_fs_sb.h"
+#include "squashfs.h"
+#include "page_actor.h"
+
+/*
+ * Look-up block in cache, and increment usage count. If not in cache, read
+ * and decompress it from disk.
+ */
+struct squashfs_cache_entry *squashfs_cache_get(struct super_block *sb,
+ struct squashfs_cache *cache, u64 block, int length)
+{
+ int i, n;
+ struct squashfs_cache_entry *entry;
+
+ while (1) {
+ for (i = cache->curr_blk, n = 0; n < cache->entries; n++) {
+ if (cache->entry[i].block == block) {
+ cache->curr_blk = i;
+ break;
+ }
+ i = (i + 1) % cache->entries;
+ }
+
+ if (n == cache->entries) {
+
+ /*
+ * At least one unused cache entry. A simple
+ * round-robin strategy is used to choose the entry to
+ * be evicted from the cache.
+ */
+ i = cache->next_blk;
+ for (n = 0; n < cache->entries; n++) {
+ if (cache->entry[i].refcount == 0)
+ break;
+ i = (i + 1) % cache->entries;
+ }
+
+ cache->next_blk = (i + 1) % cache->entries;
+ entry = &cache->entry[i];
+
+ /*
+ * Initialise chosen cache entry, and fill it in from
+ * disk.
+ */
+ cache->unused--;
+ entry->block = block;
+ entry->refcount = 1;
+ entry->pending = 1;
+ entry->error = 0;
+
+ entry->length = squashfs_read_data(sb, block, length,
+ &entry->next_index, entry->actor);
+
+ if (entry->length < 0)
+ entry->error = entry->length;
+
+ entry->pending = 0;
+
+ goto out;
+ }
+
+ /*
+ * Block already in cache. Increment refcount so it doesn't
+ * get reused until we're finished with it, if it was
+ * previously unused there's one less cache entry available
+ * for reuse.
+ */
+ entry = &cache->entry[i];
+ if (entry->refcount == 0)
+ cache->unused--;
+ entry->refcount++;
+
+ goto out;
+ }
+
+out:
+ TRACE("Got %s %d, start block %lld, refcount %d, error %d\n",
+ cache->name, i, entry->block, entry->refcount, entry->error);
+
+ if (entry->error)
+ ERROR("Unable to read %s cache entry [%llx]\n", cache->name,
+ block);
+ return entry;
+}
+
+
+/*
+ * Release cache entry, once usage count is zero it can be reused.
+ */
+void squashfs_cache_put(struct squashfs_cache_entry *entry)
+{
+ struct squashfs_cache *cache = entry->cache;
+
+ entry->refcount--;
+ if (entry->refcount == 0)
+ cache->unused++;
+}
+
+/*
+ * Delete cache reclaiming all kmalloced buffers.
+ */
+void squashfs_cache_delete(struct squashfs_cache *cache)
+{
+ int i, j;
+
+ if (cache == NULL)
+ return;
+
+ for (i = 0; i < cache->entries; i++) {
+ if (cache->entry[i].data) {
+ for (j = 0; j < cache->pages; j++)
+ kfree(cache->entry[i].data[j]);
+ kfree(cache->entry[i].data);
+ }
+ kfree(cache->entry[i].actor);
+ }
+
+ kfree(cache->entry);
+ kfree(cache);
+}
+
+
+/*
+ * Initialise cache allocating the specified number of entries, each of
+ * size block_size. To avoid vmalloc fragmentation issues each entry
+ * is allocated as a sequence of kmalloced PAGE_CACHE_SIZE buffers.
+ */
+struct squashfs_cache *squashfs_cache_init(char *name, int entries,
+ int block_size)
+{
+ int i, j;
+ struct squashfs_cache *cache = kzalloc(sizeof(*cache), GFP_KERNEL);
+
+ if (cache == NULL) {
+ ERROR("Failed to allocate %s cache\n", name);
+ return NULL;
+ }
+
+ cache->entry = calloc(entries, sizeof(*(cache->entry)));
+ if (cache->entry == NULL) {
+ ERROR("Failed to allocate %s cache\n", name);
+ goto cleanup;
+ }
+
+ cache->curr_blk = 0;
+ cache->next_blk = 0;
+ cache->unused = entries;
+ cache->entries = entries;
+ cache->block_size = block_size;
+ cache->pages = block_size >> PAGE_CACHE_SHIFT;
+ cache->pages = cache->pages ? cache->pages : 1;
+ cache->name = name;
+
+ for (i = 0; i < entries; i++) {
+ struct squashfs_cache_entry *entry = &cache->entry[i];
+
+ entry->cache = cache;
+ entry->block = SQUASHFS_INVALID_BLK;
+ entry->data = calloc(cache->pages, sizeof(void *));
+ if (entry->data == NULL) {
+ ERROR("Failed to allocate %s cache entry\n", name);
+ goto cleanup;
+ }
+
+ for (j = 0; j < cache->pages; j++) {
+ entry->data[j] = kmalloc(PAGE_CACHE_SIZE, GFP_KERNEL);
+ if (entry->data[j] == NULL) {
+ ERROR("Failed to allocate %s buffer\n", name);
+ goto cleanup;
+ }
+ }
+
+ entry->actor = squashfs_page_actor_init(entry->data,
+ cache->pages, 0);
+ if (entry->actor == NULL) {
+ ERROR("Failed to allocate %s cache entry\n", name);
+ goto cleanup;
+ }
+ }
+
+ return cache;
+
+cleanup:
+ squashfs_cache_delete(cache);
+ return NULL;
+}
+
+
+/*
+ * Copy up to length bytes from cache entry to buffer starting at offset bytes
+ * into the cache entry. If there's not length bytes then copy the number of
+ * bytes available. In all cases return the number of bytes copied.
+ */
+int squashfs_copy_data(void *buffer, struct squashfs_cache_entry *entry,
+ int offset, int length)
+{
+ int remaining = length;
+
+ if (length == 0)
+ return 0;
+ else if (buffer == NULL)
+ return min(length, entry->length - offset);
+
+ while (offset < entry->length) {
+ void *buff = entry->data[offset / PAGE_CACHE_SIZE]
+ + (offset % PAGE_CACHE_SIZE);
+ int bytes = min_t(int, entry->length - offset,
+ PAGE_CACHE_SIZE - (offset % PAGE_CACHE_SIZE));
+
+ if (bytes >= remaining) {
+ memcpy(buffer, buff, remaining);
+ remaining = 0;
+ break;
+ }
+
+ memcpy(buffer, buff, bytes);
+ buffer += bytes;
+ remaining -= bytes;
+ offset += bytes;
+ }
+
+ return length - remaining;
+}
+
+
+/*
+ * Read length bytes from metadata position <block, offset> (block is the
+ * start of the compressed block on disk, and offset is the offset into
+ * the block once decompressed). Data is packed into consecutive blocks,
+ * and length bytes may require reading more than one block.
+ */
+int squashfs_read_metadata(struct super_block *sb, void *buffer,
+ u64 *block, int *offset, int length)
+{
+ struct squashfs_sb_info *msblk = sb->s_fs_info;
+ int bytes, res = length;
+ struct squashfs_cache_entry *entry;
+
+ TRACE("Entered squashfs_read_metadata [%llx:%x]\n", *block, *offset);
+
+ while (length) {
+ entry = squashfs_cache_get(sb, msblk->block_cache, *block, 0);
+ if (entry->error) {
+ TRACE("entry->error\n");
+ res = entry->error;
+ goto error;
+ } else if (*offset >= entry->length) {
+ TRACE("entry->length\n");
+ res = -EIO;
+ goto error;
+ }
+
+ bytes = squashfs_copy_data(buffer, entry, *offset, length);
+ if (buffer)
+ buffer += bytes;
+ length -= bytes;
+ *offset += bytes;
+
+ if (*offset == entry->length) {
+ *block = entry->next_index;
+ *offset = 0;
+ }
+
+ squashfs_cache_put(entry);
+ }
+
+ return res;
+
+error:
+ squashfs_cache_put(entry);
+ return res;
+}
+
+
+/*
+ * Look-up in the fragmment cache the fragment located at <start_block> in the
+ * filesystem. If necessary read and decompress it from disk.
+ */
+struct squashfs_cache_entry *squashfs_get_fragment(struct super_block *sb,
+ u64 start_block, int length)
+{
+ struct squashfs_sb_info *msblk = sb->s_fs_info;
+
+ return squashfs_cache_get(sb, msblk->fragment_cache, start_block,
+ length);
+}
+
+
+/*
+ * Read and decompress the datablock located at <start_block> in the
+ * filesystem. The cache is used here to avoid duplicating locking and
+ * read/decompress code.
+ */
+struct squashfs_cache_entry *squashfs_get_datablock(struct super_block *sb,
+ u64 start_block, int length)
+{
+ struct squashfs_sb_info *msblk = sb->s_fs_info;
+
+ return squashfs_cache_get(sb, msblk->read_page, start_block, length);
+}
+
+/*
+ * Read a filesystem table (uncompressed sequence of bytes) from disk
+ */
+void *squashfs_read_table(struct super_block *sb, u64 block, int length)
+{
+ int pages = (length + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
+ int i, res;
+ void *table, *buffer, **data;
+ struct squashfs_page_actor *actor;
+
+ table = buffer = kmalloc(length, GFP_KERNEL);
+ if (table == NULL)
+ return ERR_PTR(-ENOMEM);
+
+ data = calloc(pages, sizeof(void *));
+ if (data == NULL) {
+ res = -ENOMEM;
+ goto failed;
+ }
+
+ actor = squashfs_page_actor_init(data, pages, length);
+ if (actor == NULL) {
+ res = -ENOMEM;
+ goto failed2;
+ }
+
+ for (i = 0; i < pages; i++, buffer += PAGE_CACHE_SIZE)
+ data[i] = buffer;
+
+ res = squashfs_read_data(sb, block, length |
+ SQUASHFS_COMPRESSED_BIT_BLOCK, NULL, actor);
+
+ kfree(data);
+ kfree(actor);
+
+ if (res < 0)
+ goto failed;
+
+ return table;
+
+failed2:
+ kfree(data);
+failed:
+ kfree(table);
+ return ERR_PTR(res);
+}
diff --git a/fs/squashfs/decompressor.c b/fs/squashfs/decompressor.c
new file mode 100644
index 0000000..558457b
--- /dev/null
+++ b/fs/squashfs/decompressor.c
@@ -0,0 +1,140 @@
+/*
+ * Squashfs - a compressed read only filesystem for Linux
+ *
+ * Copyright (c) 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009
+ * Phillip Lougher <phillip at squashfs.org.uk>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2,
+ * or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * decompressor.c
+ */
+
+#include <linux/types.h>
+
+#include "squashfs_fs.h"
+#include "squashfs_fs_sb.h"
+#include "decompressor.h"
+#include "squashfs.h"
+#include "page_actor.h"
+
+/*
+ * This file (and decompressor.h) implements a decompressor framework for
+ * Squashfs, allowing multiple decompressors to be easily supported
+ */
+
+static const struct squashfs_decompressor squashfs_lzma_unsupported_comp_ops = {
+ NULL, NULL, NULL, NULL, LZMA_COMPRESSION, "lzma", 0
+};
+
+#ifndef CONFIG_SQUASHFS_LZ4
+static const struct squashfs_decompressor squashfs_lz4_comp_ops = {
+ NULL, NULL, NULL, NULL, LZ4_COMPRESSION, "lz4", 0
+};
+#endif
+
+#ifndef CONFIG_SQUASHFS_LZO
+static const struct squashfs_decompressor squashfs_lzo_comp_ops = {
+ NULL, NULL, NULL, NULL, LZO_COMPRESSION, "lzo", 0
+};
+#endif
+
+#ifndef CONFIG_SQUASHFS_XZ
+static const struct squashfs_decompressor squashfs_xz_comp_ops = {
+ NULL, NULL, NULL, NULL, XZ_COMPRESSION, "xz", 0
+};
+#endif
+
+#ifndef CONFIG_SQUASHFS_ZLIB
+static const struct squashfs_decompressor squashfs_zlib_comp_ops = {
+ NULL, NULL, NULL, NULL, ZLIB_COMPRESSION, "zlib", 0
+};
+#endif
+
+static const struct squashfs_decompressor squashfs_unknown_comp_ops = {
+ NULL, NULL, NULL, NULL, 0, "unknown", 0
+};
+
+static const struct squashfs_decompressor *decompressor[] = {
+ &squashfs_zlib_comp_ops,
+ &squashfs_lz4_comp_ops,
+ &squashfs_lzo_comp_ops,
+ &squashfs_xz_comp_ops,
+ &squashfs_lzma_unsupported_comp_ops,
+ &squashfs_unknown_comp_ops
+};
+
+
+const struct squashfs_decompressor *squashfs_lookup_decompressor(int id)
+{
+ int i;
+
+ for (i = 0; decompressor[i]->id; i++)
+ if (id == decompressor[i]->id)
+ break;
+
+ return decompressor[i];
+}
+
+
+static void *get_comp_opts(struct super_block *sb, unsigned short flags)
+{
+ struct squashfs_sb_info *msblk = sb->s_fs_info;
+ void *buffer = NULL, *comp_opts;
+ struct squashfs_page_actor *actor = NULL;
+ int length = 0;
+
+ /*
+ * Read decompressor specific options from file system if present
+ */
+ if (SQUASHFS_COMP_OPTS(flags)) {
+ buffer = kmalloc(PAGE_CACHE_SIZE, GFP_KERNEL);
+ if (buffer == NULL) {
+ comp_opts = ERR_PTR(-ENOMEM);
+ goto out;
+ }
+
+ actor = squashfs_page_actor_init(&buffer, 1, 0);
+ if (actor == NULL) {
+ comp_opts = ERR_PTR(-ENOMEM);
+ goto out;
+ }
+ length = squashfs_read_data(sb,
+ sizeof(struct squashfs_super_block), 0, NULL, actor);
+
+ if (length < 0) {
+ comp_opts = ERR_PTR(length);
+ goto out;
+ }
+ }
+
+ comp_opts = squashfs_comp_opts(msblk, buffer, length);
+
+out:
+ kfree(actor);
+ kfree(buffer);
+ return comp_opts;
+}
+
+
+void *squashfs_decompressor_setup(struct super_block *sb, unsigned short flags)
+{
+ struct squashfs_sb_info *msblk = sb->s_fs_info;
+ void *stream, *comp_opts = get_comp_opts(sb, flags);
+
+ if (IS_ERR(comp_opts))
+ return comp_opts;
+
+ stream = squashfs_decompressor_create(msblk, comp_opts);
+ if (IS_ERR(stream))
+ kfree(comp_opts);
+
+ return stream;
+}
diff --git a/fs/squashfs/decompressor.h b/fs/squashfs/decompressor.h
new file mode 100644
index 0000000..b097677
--- /dev/null
+++ b/fs/squashfs/decompressor.h
@@ -0,0 +1,57 @@
+#ifndef DECOMPRESSOR_H
+#define DECOMPRESSOR_H
+/*
+ * Squashfs - a compressed read only filesystem for Linux
+ *
+ * Copyright (c) 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009
+ * Phillip Lougher <phillip at squashfs.org.uk>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2,
+ * or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * decompressor.h
+ */
+
+struct squashfs_decompressor {
+ void *(*init)(struct squashfs_sb_info *, void *);
+ void *(*comp_opts)(struct squashfs_sb_info *, void *, int);
+ void (*free)(void *);
+ int (*decompress)(struct squashfs_sb_info *, void *,
+ char **, int, int, int,
+ struct squashfs_page_actor *);
+ int id;
+ char *name;
+ int supported;
+};
+
+static inline void *squashfs_comp_opts(struct squashfs_sb_info *msblk,
+ void *buff, int length)
+{
+ return msblk->decompressor->comp_opts ?
+ msblk->decompressor->comp_opts(msblk, buff, length) : NULL;
+}
+
+#ifdef CONFIG_SQUASHFS_XZ
+extern const struct squashfs_decompressor squashfs_xz_comp_ops;
+#endif
+
+#ifdef CONFIG_SQUASHFS_LZ4
+extern const struct squashfs_decompressor squashfs_lz4_comp_ops;
+#endif
+
+#ifdef CONFIG_SQUASHFS_LZO
+extern const struct squashfs_decompressor squashfs_lzo_comp_ops;
+#endif
+
+#ifdef CONFIG_SQUASHFS_ZLIB
+extern const struct squashfs_decompressor squashfs_zlib_comp_ops;
+#endif
+
+#endif
diff --git a/fs/squashfs/decompressor_single.c b/fs/squashfs/decompressor_single.c
new file mode 100644
index 0000000..046834c
--- /dev/null
+++ b/fs/squashfs/decompressor_single.c
@@ -0,0 +1,83 @@
+/*
+ * Copyright (c) 2013
+ * Phillip Lougher <phillip at squashfs.org.uk>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2. See
+ * the COPYING file in the top-level directory.
+ */
+
+#include <linux/types.h>
+#include <malloc.h>
+
+#include "squashfs_fs.h"
+#include "squashfs_fs_sb.h"
+#include "decompressor.h"
+#include "squashfs.h"
+
+/*
+ * This file implements single-threaded decompression in the
+ * decompressor framework
+ */
+
+struct squashfs_stream {
+ void *stream;
+ struct mutex mutex;
+};
+
+void *squashfs_decompressor_create(struct squashfs_sb_info *msblk,
+ void *comp_opts)
+{
+ struct squashfs_stream *stream;
+ int err = -ENOMEM;
+
+ stream = kmalloc(sizeof(*stream), GFP_KERNEL);
+ if (stream == NULL)
+ goto out;
+
+ stream->stream = msblk->decompressor->init(msblk, comp_opts);
+ if (IS_ERR(stream->stream)) {
+ err = PTR_ERR(stream->stream);
+ goto out;
+ }
+
+ kfree(comp_opts);
+ mutex_init(&stream->mutex);
+ return stream;
+
+out:
+ kfree(stream);
+ return ERR_PTR(err);
+}
+
+void squashfs_decompressor_destroy(struct squashfs_sb_info *msblk)
+{
+ struct squashfs_stream *stream = msblk->stream;
+
+ if (stream) {
+ msblk->decompressor->free(stream->stream);
+ kfree(stream);
+ }
+}
+
+int squashfs_decompress(struct squashfs_sb_info *msblk, char **bh,
+ int b, int offset, int length, struct squashfs_page_actor *output)
+{
+ int res;
+ struct squashfs_stream *stream = msblk->stream;
+
+ mutex_lock(&stream->mutex);
+ res = msblk->decompressor->decompress(msblk, stream->stream, bh, b,
+ offset, length, output);
+ mutex_unlock(&stream->mutex);
+
+ if (res < 0)
+ ERROR("%s decompression failed, data probably corrupt\n",
+ msblk->decompressor->name);
+
+ return res;
+}
+
+int squashfs_max_decompressors(void)
+{
+ return 1;
+}
diff --git a/fs/squashfs/file.c b/fs/squashfs/file.c
new file mode 100644
index 0000000..a4a6a4d
--- /dev/null
+++ b/fs/squashfs/file.c
@@ -0,0 +1,460 @@
+/*
+ * Squashfs - a compressed read only filesystem for Linux
+ *
+ * Copyright (c) 2002, 2003, 2004, 2005, 2006, 2007, 2008
+ * Phillip Lougher <phillip at squashfs.org.uk>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2,
+ * or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * file.c
+ */
+
+/*
+ * This file contains code for handling regular files. A regular file
+ * consists of a sequence of contiguous compressed blocks, and/or a
+ * compressed fragment block (tail-end packed block). The compressed size
+ * of each datablock is stored in a block list contained within the
+ * file inode (itself stored in one or more compressed metadata blocks).
+ *
+ * To speed up access to datablocks when reading 'large' files (256 Mbytes or
+ * larger), the code implements an index cache that caches the mapping from
+ * block index to datablock location on disk.
+ *
+ * The index cache allows Squashfs to handle large files (up to 1.75 TiB) while
+ * retaining a simple and space-efficient block list on disk. The cache
+ * is split into slots, caching up to eight 224 GiB files (128 KiB blocks).
+ * Larger files use multiple slots, with 1.75 TiB files using all 8 slots.
+ * The index cache is designed to be memory efficient, and by default uses
+ * 16 KiB.
+ */
+
+#include <malloc.h>
+#include <linux/fs.h>
+#include <linux/kernel.h>
+#include <linux/string.h>
+#include <linux/pagemap.h>
+
+#include "squashfs_fs.h"
+#include "squashfs_fs_sb.h"
+#include "squashfs_fs_i.h"
+#include "squashfs.h"
+
+/*
+ * Locate cache slot in range [offset, index] for specified inode. If
+ * there's more than one return the slot closest to index.
+ */
+static struct meta_index *locate_meta_index(struct inode *inode, int offset,
+ int index)
+{
+ struct meta_index *meta = NULL;
+ struct squashfs_sb_info *msblk = inode->i_sb->s_fs_info;
+ int i;
+
+ if (msblk->meta_index == NULL)
+ goto not_allocated;
+
+ for (i = 0; i < SQUASHFS_META_SLOTS; 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:
+ return meta;
+}
+
+
+/*
+ * Find and initialise an empty cache slot for index offset.
+ */
+static 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;
+
+ mutex_lock(&msblk->meta_index_mutex);
+
+ TRACE("empty_meta_index: offset %d, skip %d\n", offset, skip);
+
+ if (msblk->meta_index == NULL) {
+ /*
+ * First time cache index has been used, allocate and
+ * initialise. The cache index could be allocated at
+ * mount time but doing it here means it is allocated only
+ * if a 'large' file is read.
+ */
+ msblk->meta_index = calloc(SQUASHFS_META_SLOTS,
+ sizeof(*(msblk->meta_index)));
+ if (msblk->meta_index == NULL) {
+ ERROR("Failed to allocate meta_index\n");
+ goto failed;
+ }
+ for (i = 0; i < SQUASHFS_META_SLOTS; i++) {
+ msblk->meta_index[i].inode_number = 0;
+ msblk->meta_index[i].locked = 0;
+ }
+ msblk->next_meta_index = 0;
+ }
+
+ for (i = SQUASHFS_META_SLOTS; i &&
+ msblk->meta_index[msblk->next_meta_index].locked; i--)
+ msblk->next_meta_index = (msblk->next_meta_index + 1) %
+ SQUASHFS_META_SLOTS;
+
+ if (i == 0) {
+ TRACE("empty_meta_index: failed!\n");
+ goto failed;
+ }
+
+ TRACE("empty_meta_index: returned meta entry %d, %p\n",
+ msblk->next_meta_index,
+ &msblk->meta_index[msblk->next_meta_index]);
+
+ meta = &msblk->meta_index[msblk->next_meta_index];
+ msblk->next_meta_index = (msblk->next_meta_index + 1) %
+ SQUASHFS_META_SLOTS;
+
+ meta->inode_number = inode->i_ino;
+ meta->offset = offset;
+ meta->skip = skip;
+ meta->entries = 0;
+ meta->locked = 1;
+
+failed:
+ mutex_unlock(&msblk->meta_index_mutex);
+ return meta;
+}
+
+
+static void release_meta_index(struct inode *inode, struct meta_index *meta)
+{
+ struct squashfs_sb_info *msblk = inode->i_sb->s_fs_info;
+ mutex_lock(&msblk->meta_index_mutex);
+ meta->locked = 0;
+ mutex_unlock(&msblk->meta_index_mutex);
+}
+
+
+/*
+ * Read the next n blocks from the block list, starting from
+ * metadata block <start_block, offset>.
+ */
+static long long read_indexes(struct super_block *sb, int n,
+ u64 *start_block, int *offset)
+{
+ int err, i;
+ long long block = 0;
+ __le32 *blist = kmalloc(PAGE_CACHE_SIZE, GFP_KERNEL);
+
+ if (blist == NULL) {
+ ERROR("read_indexes: Failed to allocate block_list\n");
+ return -ENOMEM;
+ }
+
+ while (n) {
+ int blocks = min_t(int, n, PAGE_CACHE_SIZE >> 2);
+
+ err = squashfs_read_metadata(sb, blist, start_block,
+ offset, blocks << 2);
+ if (err < 0) {
+ ERROR("read_indexes: reading block [%llx:%x]\n",
+ *start_block, *offset);
+ goto failure;
+ }
+
+ for (i = 0; i < blocks; i++) {
+ int size = le32_to_cpu(blist[i]);
+ block += SQUASHFS_COMPRESSED_SIZE_BLOCK(size);
+ }
+ n -= blocks;
+ }
+
+ kfree(blist);
+ return block;
+
+failure:
+ kfree(blist);
+ return err;
+}
+
+
+/*
+ * Each cache index slot has SQUASHFS_META_ENTRIES, each of which
+ * can cache one index -> datablock/blocklist-block mapping. We wish
+ * to distribute these over the length of the file, entry[0] maps index x,
+ * entry[1] maps index x + skip, entry[2] maps index x + 2 * skip, and so on.
+ * The larger the file, the greater the skip factor. The skip factor is
+ * limited to the size of the metadata cache (SQUASHFS_CACHED_BLKS) to ensure
+ * the number of metadata blocks that need to be read fits into the cache.
+ * If the skip factor is limited in this way then the file will use multiple
+ * slots.
+ */
+static inline int calculate_skip(int blocks)
+{
+ int skip = blocks / ((SQUASHFS_META_ENTRIES + 1)
+ * SQUASHFS_META_INDEXES);
+ return min(SQUASHFS_CACHED_BLKS - 1, skip + 1);
+}
+
+
+/*
+ * Search and grow the index cache for the specified inode, returning the
+ * on-disk locations of the datablock and block list metadata block
+ * <index_block, index_offset> for index (scaled to nearest cache index).
+ */
+static int fill_meta_index(struct inode *inode, int index,
+ u64 *index_block, int *index_offset, u64 *data_block)
+{
+ struct squashfs_sb_info *msblk = inode->i_sb->s_fs_info;
+ int skip = calculate_skip(i_size_read(inode) >> msblk->block_log);
+ int offset = 0;
+ struct meta_index *meta;
+ struct meta_entry *meta_entry;
+ u64 cur_index_block = squashfs_i(inode)->block_list_start;
+ int cur_offset = squashfs_i(inode)->offset;
+ u64 cur_data_block = squashfs_i(inode)->start;
+ int err, i;
+
+ /*
+ * Scale index to cache index (cache slot entry)
+ */
+ index /= SQUASHFS_META_INDEXES * skip;
+
+ while (offset < index) {
+ meta = locate_meta_index(inode, offset + 1, index);
+
+ if (meta == NULL) {
+ meta = empty_meta_index(inode, offset + 1, skip);
+ if (meta == NULL)
+ goto all_done;
+ } else {
+ offset = index < meta->offset + meta->entries ? index :
+ meta->offset + meta->entries - 1;
+ meta_entry = &meta->meta_entry[offset - meta->offset];
+ cur_index_block = meta_entry->index_block +
+ msblk->inode_table;
+ cur_offset = meta_entry->offset;
+ cur_data_block = meta_entry->data_block;
+ TRACE("get_meta_index: offset %d, meta->offset %d, "
+ "meta->entries %d\n", offset, meta->offset,
+ meta->entries);
+ TRACE("get_meta_index: index_block 0x%llx, offset 0x%x"
+ " data_block 0x%llx\n", cur_index_block,
+ cur_offset, cur_data_block);
+ }
+
+ /*
+ * If necessary grow cache slot by reading block list. Cache
+ * slot is extended up to index or to the end of the slot, in
+ * which case further slots will be used.
+ */
+ for (i = meta->offset + meta->entries; i <= index &&
+ i < meta->offset + SQUASHFS_META_ENTRIES; i++) {
+ int blocks = skip * SQUASHFS_META_INDEXES;
+ long long res = read_indexes(inode->i_sb, blocks,
+ &cur_index_block, &cur_offset);
+
+ if (res < 0) {
+ if (meta->entries == 0)
+ /*
+ * Don't leave an empty slot on read
+ * error allocated to this inode...
+ */
+ meta->inode_number = 0;
+ err = res;
+ goto failed;
+ }
+
+ cur_data_block += res;
+ meta_entry = &meta->meta_entry[i - meta->offset];
+ meta_entry->index_block = cur_index_block -
+ msblk->inode_table;
+ meta_entry->offset = cur_offset;
+ meta_entry->data_block = cur_data_block;
+ meta->entries++;
+ offset++;
+ }
+
+ TRACE("get_meta_index: meta->offset %d, meta->entries %d\n",
+ meta->offset, meta->entries);
+
+ release_meta_index(inode, meta);
+ }
+
+all_done:
+ *index_block = cur_index_block;
+ *index_offset = cur_offset;
+ *data_block = cur_data_block;
+
+ /*
+ * Scale cache index (cache slot entry) to index
+ */
+ return offset * SQUASHFS_META_INDEXES * skip;
+
+failed:
+ release_meta_index(inode, meta);
+ return err;
+}
+
+
+/*
+ * Get the on-disk location and compressed size of the datablock
+ * specified by index. Fill_meta_index() does most of the work.
+ */
+static int read_blocklist(struct inode *inode, int index, u64 *block)
+{
+ u64 start;
+ long long blks;
+ int offset;
+ __le32 size;
+ int res = fill_meta_index(inode, index, &start, &offset, block);
+
+ TRACE("read_blocklist: res %d, index %d, start 0x%llx, offset"
+ " 0x%x, block 0x%llx\n", res, index, start, offset,
+ *block);
+
+ if (res < 0)
+ return res;
+
+ /*
+ * res contains the index of the mapping returned by fill_meta_index(),
+ * this will likely be less than the desired index (because the
+ * meta_index cache works at a higher granularity). Read any
+ * extra block indexes needed.
+ */
+ if (res < index) {
+ blks = read_indexes(inode->i_sb, index - res, &start, &offset);
+ if (blks < 0)
+ return (int) blks;
+ *block += blks;
+ }
+
+ /*
+ * Read length of block specified by index.
+ */
+ res = squashfs_read_metadata(inode->i_sb, &size, &start, &offset,
+ sizeof(size));
+ if (res < 0)
+ return res;
+ return le32_to_cpu(size);
+}
+
+/* Copy data into page cache */
+void squashfs_copy_cache(struct page *page, struct squashfs_cache_entry *buffer,
+ int bytes, int offset)
+{
+ int i;
+ struct squashfs_page *sq_page = squashfs_page(page);
+
+ /*
+ * Loop copying datablock into pages. As the datablock likely covers
+ * many PAGE_CACHE_SIZE pages (default block size is 128 KiB) explicitly
+ * grab the pages from the page cache, except for the page that we've
+ * been called to fill.
+ */
+ for (i = 0; i < 32 && bytes > 0; i++,
+ bytes -= PAGE_CACHE_SIZE, offset += PAGE_CACHE_SIZE) {
+ int avail = buffer ? min_t(int, bytes, PAGE_CACHE_SIZE) : 0;
+
+ TRACE("bytes %d, i %d, available_bytes %d\n", bytes, i, avail);
+
+ squashfs_copy_data(sq_page->buf[i], buffer, offset, avail);
+ memset(sq_page->buf[i] + avail, 0, PAGE_CACHE_SIZE - avail);
+ sq_page->idx++;
+ }
+}
+
+/* Read datablock stored packed inside a fragment (tail-end packed block) */
+static int squashfs_readpage_fragment(struct page *page)
+{
+ struct inode *inode = page->inode;
+ struct squashfs_sb_info *msblk = inode->i_sb->s_fs_info;
+ struct squashfs_cache_entry *buffer = squashfs_get_fragment(inode->i_sb,
+ squashfs_i(inode)->fragment_block,
+ squashfs_i(inode)->fragment_size);
+ int res = buffer->error;
+
+ TRACE("squashfs_readpage_fragment: frag size: %d\n",
+ squashfs_i(inode)->fragment_size);
+ if (res)
+ ERROR("Unable to read page, block %llx, size %x\n",
+ squashfs_i(inode)->fragment_block,
+ squashfs_i(inode)->fragment_size);
+ else
+ squashfs_copy_cache(page, buffer, i_size_read(inode) &
+ (msblk->block_size - 1),
+ squashfs_i(inode)->fragment_offset);
+
+ squashfs_cache_put(buffer);
+ return res;
+}
+
+static int squashfs_readpage_sparse(struct page *page, int index, int file_end)
+{
+ struct inode *inode = page->inode;
+ struct squashfs_sb_info *msblk = inode->i_sb->s_fs_info;
+ int bytes = index == file_end ?
+ (i_size_read(inode) & (msblk->block_size - 1)) :
+ msblk->block_size;
+
+ squashfs_copy_cache(page, NULL, bytes, 0);
+
+ return 0;
+}
+
+int squashfs_readpage(struct file *file, struct page *page)
+{
+ struct inode *inode = page->inode;
+ struct squashfs_sb_info *msblk = inode->i_sb->s_fs_info;
+ int index = page->index >> (msblk->block_log - PAGE_CACHE_SHIFT);
+ int file_end = i_size_read(inode) >> msblk->block_log;
+ int res;
+
+ TRACE("Entered squashfs_readpage, page index %lx, start block %llx\n",
+ page->index, squashfs_i(inode)->start);
+
+ if (page->index >= ((i_size_read(inode) + PAGE_CACHE_SIZE - 1) >>
+ PAGE_CACHE_SHIFT))
+ goto out;
+
+ if (index < file_end || squashfs_i(inode)->fragment_block ==
+ SQUASHFS_INVALID_BLK) {
+ u64 block = 0;
+ int bsize = read_blocklist(inode, index, &block);
+ if (bsize < 0)
+ goto out;
+
+ if (bsize == 0)
+ res = squashfs_readpage_sparse(page, index, file_end);
+ else
+ res = squashfs_readpage_block(page, block, bsize);
+ } else
+ res = squashfs_readpage_fragment(page);
+
+ if (!res)
+ return 0;
+
+out:
+ memset(page->addr, 0, PAGE_CACHE_SIZE);
+
+ return 0;
+}
diff --git a/fs/squashfs/file_cache.c b/fs/squashfs/file_cache.c
new file mode 100644
index 0000000..9443e45
--- /dev/null
+++ b/fs/squashfs/file_cache.c
@@ -0,0 +1,35 @@
+/*
+ * Copyright (c) 2013
+ * Phillip Lougher <phillip at squashfs.org.uk>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2. See
+ * the COPYING file in the top-level directory.
+ */
+
+#include <linux/fs.h>
+#include <linux/kernel.h>
+#include <linux/string.h>
+#include <linux/pagemap.h>
+
+#include "squashfs_fs.h"
+#include "squashfs_fs_sb.h"
+#include "squashfs_fs_i.h"
+#include "squashfs.h"
+
+/* Read separately compressed datablock and memcopy into page cache */
+int squashfs_readpage_block(struct page *page, u64 block, int bsize)
+{
+ struct inode *i = page->inode;
+ struct squashfs_cache_entry *buffer = squashfs_get_datablock(i->i_sb,
+ block, bsize);
+ int res = buffer->error;
+
+ if (res)
+ ERROR("Unable to read page, block %llx, size %x\n", block,
+ bsize);
+ else
+ squashfs_copy_cache(page, buffer, buffer->length, 0);
+
+ squashfs_cache_put(buffer);
+ return res;
+}
diff --git a/fs/squashfs/fragment.c b/fs/squashfs/fragment.c
new file mode 100644
index 0000000..2b99ff5
--- /dev/null
+++ b/fs/squashfs/fragment.c
@@ -0,0 +1,94 @@
+/*
+ * Squashfs - a compressed read only filesystem for Linux
+ *
+ * Copyright (c) 2002, 2003, 2004, 2005, 2006, 2007, 2008
+ * Phillip Lougher <phillip at squashfs.org.uk>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2,
+ * or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * fragment.c
+ */
+
+/*
+ * This file implements code to handle compressed fragments (tail-end packed
+ * datablocks).
+ *
+ * Regular files contain a fragment index which is mapped to a fragment
+ * location on disk and compressed size using a fragment lookup table.
+ * Like everything in Squashfs this fragment lookup table is itself stored
+ * compressed into metadata blocks. A second index table is used to locate
+ * these. This second index table for speed of access (and because it
+ * is small) is read at mount time and cached in memory.
+ */
+
+#include <malloc.h>
+#include <linux/fs.h>
+
+#include "squashfs_fs.h"
+#include "squashfs_fs_sb.h"
+#include "squashfs.h"
+
+/*
+ * Look-up fragment using the fragment index table. Return the on disk
+ * location of the fragment and its compressed size
+ */
+int squashfs_frag_lookup(struct super_block *sb, unsigned int fragment,
+ u64 *fragment_block)
+{
+ struct squashfs_sb_info *msblk = sb->s_fs_info;
+ int block = SQUASHFS_FRAGMENT_INDEX(fragment);
+ int offset = SQUASHFS_FRAGMENT_INDEX_OFFSET(fragment);
+ u64 start_block = le64_to_cpu(msblk->fragment_index[block]);
+ struct squashfs_fragment_entry fragment_entry;
+ int size;
+
+ size = squashfs_read_metadata(sb, &fragment_entry, &start_block,
+ &offset, sizeof(fragment_entry));
+ if (size < 0)
+ return size;
+
+ *fragment_block = le64_to_cpu(fragment_entry.start_block);
+ size = le32_to_cpu(fragment_entry.size);
+
+ return size;
+}
+
+
+/*
+ * Read the uncompressed fragment lookup table indexes off disk into memory
+ */
+__le64 *squashfs_read_fragment_index_table(struct super_block *sb,
+ u64 fragment_table_start, u64 next_table, unsigned int fragments)
+{
+ unsigned int length = SQUASHFS_FRAGMENT_INDEX_BYTES(fragments);
+ __le64 *table;
+
+ /*
+ * Sanity check, length bytes should not extend into the next table -
+ * this check also traps instances where fragment_table_start is
+ * incorrectly larger than the next table start
+ */
+ if (fragment_table_start + length > next_table)
+ return ERR_PTR(-EINVAL);
+
+ table = squashfs_read_table(sb, fragment_table_start, length);
+
+ /*
+ * table[0] points to the first fragment table metadata block, this
+ * should be less than fragment_table_start
+ */
+ if (!IS_ERR(table) && le64_to_cpu(table[0]) >= fragment_table_start) {
+ kfree(table);
+ return ERR_PTR(-EINVAL);
+ }
+
+ return table;
+}
diff --git a/fs/squashfs/id.c b/fs/squashfs/id.c
new file mode 100644
index 0000000..5db0f73
--- /dev/null
+++ b/fs/squashfs/id.c
@@ -0,0 +1,98 @@
+/*
+ * Squashfs - a compressed read only filesystem for Linux
+ *
+ * Copyright (c) 2002, 2003, 2004, 2005, 2006, 2007, 2008
+ * Phillip Lougher <phillip at squashfs.org.uk>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2,
+ * or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * id.c
+ */
+
+/*
+ * This file implements code to handle uids and gids.
+ *
+ * For space efficiency regular files store uid and gid indexes, which are
+ * converted to 32-bit uids/gids using an id look up table. This table is
+ * stored compressed into metadata blocks. A second index table is used to
+ * locate these. This second index table for speed of access (and because it
+ * is small) is read at mount time and cached in memory.
+ */
+
+#include <linux/barebox-wrapper.h>
+#include <linux/fs.h>
+#include <malloc.h>
+
+#include "squashfs_fs.h"
+#include "squashfs_fs_sb.h"
+#include "squashfs.h"
+
+/*
+ * Map uid/gid index into real 32-bit uid/gid using the id look up table
+ */
+int squashfs_get_id(struct super_block *sb, unsigned int index,
+ unsigned int *id)
+{
+ struct squashfs_sb_info *msblk = sb->s_fs_info;
+ int block = SQUASHFS_ID_BLOCK(index);
+ int offset = SQUASHFS_ID_BLOCK_OFFSET(index);
+ u64 start_block = le64_to_cpu(msblk->id_table[block]);
+ __le32 disk_id;
+ int err;
+
+ err = squashfs_read_metadata(sb, &disk_id, &start_block, &offset,
+ sizeof(disk_id));
+ if (err < 0)
+ return err;
+
+ *id = le32_to_cpu(disk_id);
+ return 0;
+}
+
+
+/*
+ * Read uncompressed id lookup table indexes from disk into memory
+ */
+__le64 *squashfs_read_id_index_table(struct super_block *sb,
+ u64 id_table_start, u64 next_table, unsigned short no_ids)
+{
+ unsigned int length = SQUASHFS_ID_BLOCK_BYTES(no_ids);
+ __le64 *table;
+
+ TRACE("In read_id_index_table, length %d\n", length);
+
+ /* Sanity check values */
+
+ /* there should always be at least one id */
+ if (no_ids == 0)
+ return ERR_PTR(-EINVAL);
+
+ /*
+ * length bytes should not extend into the next table - this check
+ * also traps instances where id_table_start is incorrectly larger
+ * than the next table start
+ */
+ if (id_table_start + length > next_table)
+ return ERR_PTR(-EINVAL);
+
+ table = squashfs_read_table(sb, id_table_start, length);
+
+ /*
+ * table[0] points to the first id lookup table metadata block, this
+ * should be less than id_table_start
+ */
+ if (!IS_ERR(table) && le64_to_cpu(table[0]) >= id_table_start) {
+ kfree(table);
+ return ERR_PTR(-EINVAL);
+ }
+
+ return table;
+}
diff --git a/fs/squashfs/inode.c b/fs/squashfs/inode.c
new file mode 100644
index 0000000..749fc7e
--- /dev/null
+++ b/fs/squashfs/inode.c
@@ -0,0 +1,402 @@
+/*
+ * Squashfs - a compressed read only filesystem for Linux
+ *
+ * Copyright (c) 2002, 2003, 2004, 2005, 2006, 2007, 2008
+ * Phillip Lougher <phillip at squashfs.org.uk>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2,
+ * or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * inode.c
+ */
+
+/*
+ * This file implements code to create and read inodes from disk.
+ *
+ * Inodes in Squashfs are identified by a 48-bit inode which encodes the
+ * location of the compressed metadata block containing the inode, and the byte
+ * offset into that block where the inode is placed (<block, offset>).
+ *
+ * To maximise compression there are different inodes for each file type
+ * (regular file, directory, device, etc.), the inode contents and length
+ * varying with the type.
+ *
+ * To further maximise compression, two types of regular file inode and
+ * directory inode are defined: inodes optimised for frequently occurring
+ * regular files and directories, and extended types where extra
+ * information has to be stored.
+ */
+
+#include <malloc.h>
+#include <linux/fs.h>
+#include <linux/stat.h>
+#include <linux/pagemap.h>
+
+#include "squashfs_fs.h"
+#include "squashfs_fs_sb.h"
+#include "squashfs_fs_i.h"
+#include "squashfs.h"
+
+struct inode *iget_locked_squashfs(struct super_block *sb, unsigned long ino)
+{
+ struct inode *inode;
+ struct squashfs_inode_info *ei;
+
+ ei = malloc(sizeof(struct squashfs_inode_info));
+ inode = &ei->vfs_inode;
+ if (inode) {
+ inode->i_ino = ino;
+ inode->i_sb = sb;
+ inode->i_state = I_SYNC | I_NEW;
+ }
+
+ return inode;
+}
+
+/*
+ * Initialise VFS inode with the base inode information common to all
+ * Squashfs inode types. Sqsh_ino contains the unswapped base inode
+ * off disk.
+ */
+static int squashfs_new_inode(struct super_block *sb, struct inode *inode,
+ struct squashfs_base_inode *sqsh_ino)
+{
+ uid_t i_uid;
+ gid_t i_gid;
+ int err;
+
+ err = squashfs_get_id(sb, le16_to_cpu(sqsh_ino->uid), &i_uid);
+ if (err)
+ return err;
+
+ err = squashfs_get_id(sb, le16_to_cpu(sqsh_ino->guid), &i_gid);
+ if (err)
+ return err;
+
+ inode->i_ino = le32_to_cpu(sqsh_ino->inode_number);
+ inode->i_mtime.tv_sec = le32_to_cpu(sqsh_ino->mtime);
+ inode->i_atime.tv_sec = inode->i_mtime.tv_sec;
+ inode->i_ctime.tv_sec = inode->i_mtime.tv_sec;
+ inode->i_mode = le16_to_cpu(sqsh_ino->mode);
+ inode->i_size = 0;
+
+ return err;
+}
+
+
+struct inode *squashfs_iget(struct super_block *sb, long long ino,
+ unsigned int ino_number)
+{
+ struct inode *inode = iget_locked_squashfs(sb, ino_number);
+ int err;
+
+ TRACE("Entered squashfs_iget\n");
+
+ if (!inode)
+ return ERR_PTR(-ENOMEM);
+ if (!(inode->i_state & I_NEW))
+ return inode;
+
+ err = squashfs_read_inode(inode, ino);
+ if (err)
+ return ERR_PTR(err);
+
+ return inode;
+}
+
+
+/*
+ * Initialise VFS inode by reading inode from inode table (compressed
+ * metadata). The format and amount of data read depends on type.
+ */
+int squashfs_read_inode(struct inode *inode, long long ino)
+{
+ struct super_block *sb = inode->i_sb;
+ struct squashfs_sb_info *msblk = sb->s_fs_info;
+ u64 block = SQUASHFS_INODE_BLK(ino) + msblk->inode_table;
+ int err, type, offset = SQUASHFS_INODE_OFFSET(ino);
+ union squashfs_inode squashfs_ino;
+ struct squashfs_base_inode *sqshb_ino = &squashfs_ino.base;
+ int xattr_id = SQUASHFS_INVALID_XATTR;
+
+ TRACE("Entered squashfs_read_inode: %d\n", ino);
+
+ /*
+ * Read inode base common to all inode types.
+ */
+ err = squashfs_read_metadata(sb, sqshb_ino, &block,
+ &offset, sizeof(*sqshb_ino));
+ if (err < 0)
+ goto failed_read;
+
+ err = squashfs_new_inode(sb, inode, sqshb_ino);
+ if (err)
+ goto failed_read;
+
+ block = SQUASHFS_INODE_BLK(ino) + msblk->inode_table;
+ offset = SQUASHFS_INODE_OFFSET(ino);
+
+ type = le16_to_cpu(sqshb_ino->inode_type);
+ switch (type) {
+ case SQUASHFS_REG_TYPE: {
+ unsigned int frag_offset, frag;
+ int frag_size;
+ u64 frag_blk;
+ struct squashfs_reg_inode *sqsh_ino = &squashfs_ino.reg;
+
+ TRACE("Type: SQUASHFS_REG_TYPE\n");
+ err = squashfs_read_metadata(sb, sqsh_ino, &block, &offset,
+ sizeof(*sqsh_ino));
+ if (err < 0)
+ goto failed_read;
+
+ frag = le32_to_cpu(sqsh_ino->fragment);
+ if (frag != SQUASHFS_INVALID_FRAG) {
+ frag_offset = le32_to_cpu(sqsh_ino->offset);
+ frag_size = squashfs_frag_lookup(sb, frag, &frag_blk);
+ if (frag_size < 0) {
+ err = frag_size;
+ goto failed_read;
+ }
+ } else {
+ frag_blk = SQUASHFS_INVALID_BLK;
+ frag_size = 0;
+ frag_offset = 0;
+ }
+
+ inode->i_size = le32_to_cpu(sqsh_ino->file_size);
+ inode->i_mode |= S_IFREG;
+ inode->i_blocks = ((inode->i_size - 1) >> 9) + 1;
+ squashfs_i(inode)->fragment_block = frag_blk;
+ squashfs_i(inode)->fragment_size = frag_size;
+ squashfs_i(inode)->fragment_offset = frag_offset;
+ squashfs_i(inode)->start = le32_to_cpu(sqsh_ino->start_block);
+ squashfs_i(inode)->block_list_start = block;
+ squashfs_i(inode)->offset = offset;
+
+ TRACE("File inode %x:%x, start_block %llx, block_list_start "
+ "%llx, offset %x\n", SQUASHFS_INODE_BLK(ino),
+ offset, squashfs_i(inode)->start, block, offset);
+ break;
+ }
+ case SQUASHFS_LREG_TYPE: {
+ unsigned int frag_offset, frag;
+ int frag_size;
+ u64 frag_blk;
+ struct squashfs_lreg_inode *sqsh_ino = &squashfs_ino.lreg;
+
+ TRACE("Type: SQUASHFS_LREG_TYPE\n");
+ err = squashfs_read_metadata(sb, sqsh_ino, &block, &offset,
+ sizeof(*sqsh_ino));
+ if (err < 0)
+ goto failed_read;
+
+ frag = le32_to_cpu(sqsh_ino->fragment);
+ if (frag != SQUASHFS_INVALID_FRAG) {
+ frag_offset = le32_to_cpu(sqsh_ino->offset);
+ frag_size = squashfs_frag_lookup(sb, frag, &frag_blk);
+ if (frag_size < 0) {
+ err = frag_size;
+ goto failed_read;
+ }
+ } else {
+ frag_blk = SQUASHFS_INVALID_BLK;
+ frag_size = 0;
+ frag_offset = 0;
+ }
+
+ xattr_id = le32_to_cpu(sqsh_ino->xattr);
+ inode->i_size = le64_to_cpu(sqsh_ino->file_size);
+ inode->i_mode |= S_IFREG;
+ inode->i_blocks = (inode->i_size -
+ le64_to_cpu(sqsh_ino->sparse) + 511) >> 9;
+
+ squashfs_i(inode)->fragment_block = frag_blk;
+ squashfs_i(inode)->fragment_size = frag_size;
+ squashfs_i(inode)->fragment_offset = frag_offset;
+ squashfs_i(inode)->start = le64_to_cpu(sqsh_ino->start_block);
+ squashfs_i(inode)->block_list_start = block;
+ squashfs_i(inode)->offset = offset;
+
+ TRACE("File inode %x:%x, start_block %llx, block_list_start "
+ "%llx, offset %x\n", SQUASHFS_INODE_BLK(ino),
+ offset, squashfs_i(inode)->start, block, offset);
+ break;
+ }
+ case SQUASHFS_DIR_TYPE: {
+ struct squashfs_dir_inode *sqsh_ino = &squashfs_ino.dir;
+
+ TRACE("Type: SQUASHFS_DIR_TYPE\n");
+ err = squashfs_read_metadata(sb, sqsh_ino, &block, &offset,
+ sizeof(*sqsh_ino));
+ if (err < 0)
+ goto failed_read;
+
+ inode->i_size = le16_to_cpu(sqsh_ino->file_size);
+ inode->i_mode |= S_IFDIR;
+ squashfs_i(inode)->start = le32_to_cpu(sqsh_ino->start_block);
+ squashfs_i(inode)->offset = le16_to_cpu(sqsh_ino->offset);
+ squashfs_i(inode)->dir_idx_cnt = 0;
+ squashfs_i(inode)->parent = le32_to_cpu(sqsh_ino->parent_inode);
+
+ TRACE("Directory inode %x:%x, start_block %llx, offset %x\n",
+ SQUASHFS_INODE_BLK(ino), offset,
+ squashfs_i(inode)->start,
+ le16_to_cpu(sqsh_ino->offset));
+ break;
+ }
+ case SQUASHFS_LDIR_TYPE: {
+ struct squashfs_ldir_inode *sqsh_ino = &squashfs_ino.ldir;
+
+ TRACE("Type: SQUASHFS_LDIR_TYPE\n");
+ err = squashfs_read_metadata(sb, sqsh_ino, &block, &offset,
+ sizeof(*sqsh_ino));
+ if (err < 0)
+ goto failed_read;
+
+ xattr_id = le32_to_cpu(sqsh_ino->xattr);
+ inode->i_size = le32_to_cpu(sqsh_ino->file_size);
+ inode->i_mode |= S_IFDIR;
+ squashfs_i(inode)->start = le32_to_cpu(sqsh_ino->start_block);
+ squashfs_i(inode)->offset = le16_to_cpu(sqsh_ino->offset);
+ squashfs_i(inode)->dir_idx_start = block;
+ squashfs_i(inode)->dir_idx_offset = offset;
+ squashfs_i(inode)->dir_idx_cnt = le16_to_cpu(sqsh_ino->i_count);
+ squashfs_i(inode)->parent = le32_to_cpu(sqsh_ino->parent_inode);
+
+ TRACE("Long directory inode %x:%x, start_block %llx, offset "
+ "%x\n", SQUASHFS_INODE_BLK(ino), offset,
+ squashfs_i(inode)->start,
+ le16_to_cpu(sqsh_ino->offset));
+ break;
+ }
+ case SQUASHFS_SYMLINK_TYPE:
+ case SQUASHFS_LSYMLINK_TYPE: {
+ struct squashfs_symlink_inode *sqsh_ino = &squashfs_ino.symlink;
+
+ TRACE("Type: SQUASHFS_SYMLINK_TYPE\n");
+ err = squashfs_read_metadata(sb, sqsh_ino, &block, &offset,
+ sizeof(*sqsh_ino));
+ if (err < 0)
+ goto failed_read;
+
+ inode->i_size = le32_to_cpu(sqsh_ino->symlink_size);
+ inode->i_mode |= S_IFLNK;
+ squashfs_i(inode)->start = block;
+ squashfs_i(inode)->offset = offset;
+
+ if (type == SQUASHFS_LSYMLINK_TYPE) {
+ __le32 xattr;
+
+ err = squashfs_read_metadata(sb, NULL, &block,
+ &offset, inode->i_size);
+ if (err < 0)
+ goto failed_read;
+ err = squashfs_read_metadata(sb, &xattr, &block,
+ &offset, sizeof(xattr));
+ if (err < 0)
+ goto failed_read;
+ xattr_id = le32_to_cpu(xattr);
+ }
+
+ TRACE("Symbolic link inode %x:%x, start_block %llx, offset "
+ "%x\n", SQUASHFS_INODE_BLK(ino), offset,
+ block, offset);
+ break;
+ }
+ case SQUASHFS_BLKDEV_TYPE:
+ case SQUASHFS_CHRDEV_TYPE: {
+ struct squashfs_dev_inode *sqsh_ino = &squashfs_ino.dev;
+ unsigned int rdev;
+
+ TRACE("Type: SQUASHFS_BLLDEV_TYPE\n");
+ err = squashfs_read_metadata(sb, sqsh_ino, &block, &offset,
+ sizeof(*sqsh_ino));
+ if (err < 0)
+ goto failed_read;
+
+ if (type == SQUASHFS_CHRDEV_TYPE)
+ inode->i_mode |= S_IFCHR;
+ else
+ inode->i_mode |= S_IFBLK;
+ rdev = le32_to_cpu(sqsh_ino->rdev);
+
+ TRACE("Device inode %x:%x, rdev %x\n",
+ SQUASHFS_INODE_BLK(ino), offset, rdev);
+ break;
+ }
+ case SQUASHFS_LBLKDEV_TYPE:
+ case SQUASHFS_LCHRDEV_TYPE: {
+ struct squashfs_ldev_inode *sqsh_ino = &squashfs_ino.ldev;
+ unsigned int rdev;
+
+ TRACE("Type: SQUASHFS_LBLLDEV_TYPE\n");
+ err = squashfs_read_metadata(sb, sqsh_ino, &block, &offset,
+ sizeof(*sqsh_ino));
+ if (err < 0)
+ goto failed_read;
+
+ if (type == SQUASHFS_LCHRDEV_TYPE)
+ inode->i_mode |= S_IFCHR;
+ else
+ inode->i_mode |= S_IFBLK;
+ xattr_id = le32_to_cpu(sqsh_ino->xattr);
+ rdev = le32_to_cpu(sqsh_ino->rdev);
+
+ TRACE("Device inode %x:%x, rdev %x\n",
+ SQUASHFS_INODE_BLK(ino), offset, rdev);
+ break;
+ }
+ case SQUASHFS_FIFO_TYPE:
+ case SQUASHFS_SOCKET_TYPE: {
+ struct squashfs_ipc_inode *sqsh_ino = &squashfs_ino.ipc;
+
+ TRACE("Type: SQUASHFS_FIFO_TYPE\n");
+ err = squashfs_read_metadata(sb, sqsh_ino, &block, &offset,
+ sizeof(*sqsh_ino));
+ if (err < 0)
+ goto failed_read;
+
+ if (type == SQUASHFS_FIFO_TYPE)
+ inode->i_mode |= S_IFIFO;
+ else
+ inode->i_mode |= S_IFSOCK;
+ break;
+ }
+ case SQUASHFS_LFIFO_TYPE:
+ case SQUASHFS_LSOCKET_TYPE: {
+ struct squashfs_lipc_inode *sqsh_ino = &squashfs_ino.lipc;
+
+ TRACE("Type: SQUASHFS_LFIFO_TYPE\n");
+ err = squashfs_read_metadata(sb, sqsh_ino, &block, &offset,
+ sizeof(*sqsh_ino));
+ if (err < 0)
+ goto failed_read;
+
+ if (type == SQUASHFS_LFIFO_TYPE)
+ inode->i_mode |= S_IFIFO;
+ else
+ inode->i_mode |= S_IFSOCK;
+ xattr_id = le32_to_cpu(sqsh_ino->xattr);
+ break;
+ }
+ default:
+ ERROR("Unknown inode type %d in squashfs_iget!\n", type);
+ return -EINVAL;
+ }
+
+ squashfs_i(inode)->xattr_count = 0;
+
+ return 0;
+
+failed_read:
+ ERROR("Unable to read inode 0x%llx\n", ino);
+ return err;
+}
diff --git a/fs/squashfs/namei.c b/fs/squashfs/namei.c
new file mode 100644
index 0000000..a0dc498
--- /dev/null
+++ b/fs/squashfs/namei.c
@@ -0,0 +1,381 @@
+/*
+ * Squashfs - a compressed read only filesystem for Linux
+ *
+ * Copyright (c) 2002, 2003, 2004, 2005, 2006, 2007, 2008
+ * Phillip Lougher <phillip at squashfs.org.uk>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2,
+ * or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * namei.c
+ */
+
+/*
+ * This file implements code to do filename lookup in directories.
+ *
+ * Like inodes, directories are packed into compressed metadata blocks, stored
+ * in a directory table. Directories are accessed using the start address of
+ * the metablock containing the directory and the offset into the
+ * decompressed block (<block, offset>).
+ *
+ * Directories are organised in a slightly complex way, and are not simply
+ * a list of file names. The organisation takes advantage of the
+ * fact that (in most cases) the inodes of the files will be in the same
+ * compressed metadata block, and therefore, can share the start block.
+ * Directories are therefore organised in a two level list, a directory
+ * header containing the shared start block value, and a sequence of directory
+ * entries, each of which share the shared start block. A new directory header
+ * is written once/if the inode start block changes. The directory
+ * header/directory entry list is repeated as many times as necessary.
+ *
+ * Directories are sorted, and can contain a directory index to speed up
+ * file lookup. Directory indexes store one entry per metablock, each entry
+ * storing the index/filename mapping to the first directory header
+ * in each metadata block. Directories are sorted in alphabetical order,
+ * and at lookup the index is scanned linearly looking for the first filename
+ * alphabetically larger than the filename being looked up. At this point the
+ * location of the metadata block the filename is in has been found.
+ * The general idea of the index is ensure only one metadata block needs to be
+ * decompressed to do a lookup irrespective of the length of the directory.
+ * This scheme has the advantage that it doesn't require extra memory overhead
+ * and doesn't require much extra storage on disk.
+ */
+
+#include <linux/fs.h>
+#include <malloc.h>
+#include <linux/string.h>
+#include <linux/dcache.h>
+#include <common.h>
+
+#include "squashfs_fs.h"
+#include "squashfs_fs_sb.h"
+#include "squashfs_fs_i.h"
+#include "squashfs.h"
+
+/*
+ * Lookup name in the directory index, returning the location of the metadata
+ * block containing it, and the directory index this represents.
+ *
+ * If we get an error reading the index then return the part of the index
+ * (if any) we have managed to read - the index isn't essential, just
+ * quicker.
+ */
+static int get_dir_index_using_name(struct super_block *sb,
+ u64 *next_block, int *next_offset, u64 index_start,
+ int index_offset, int i_count, const char *name,
+ int len)
+{
+ struct squashfs_sb_info *msblk = sb->s_fs_info;
+ int i, length = 0, err;
+ unsigned int size;
+ struct squashfs_dir_index *index;
+ char *str;
+
+ TRACE("Entered get_dir_index_using_name, i_count %d\n", i_count);
+
+ index = kmalloc(sizeof(*index) + SQUASHFS_NAME_LEN * 2 + 2, GFP_KERNEL);
+ if (index == NULL) {
+ ERROR("Failed to allocate squashfs_dir_index\n");
+ goto out;
+ }
+
+ str = &index->name[SQUASHFS_NAME_LEN + 1];
+ strncpy(str, name, len);
+ str[len] = '\0';
+
+ for (i = 0; i < i_count; i++) {
+ err = squashfs_read_metadata(sb, index, &index_start,
+ &index_offset, sizeof(*index));
+ if (err < 0)
+ break;
+
+
+ size = le32_to_cpu(index->size) + 1;
+ if (size > SQUASHFS_NAME_LEN)
+ break;
+
+ err = squashfs_read_metadata(sb, index->name, &index_start,
+ &index_offset, size);
+ if (err < 0)
+ break;
+
+ index->name[size] = '\0';
+
+ if (strcmp(index->name, str) > 0)
+ break;
+
+ length = le32_to_cpu(index->index);
+ *next_block = le32_to_cpu(index->start_block) +
+ msblk->directory_table;
+ }
+
+ *next_offset = (length + *next_offset) % SQUASHFS_METADATA_SIZE;
+ kfree(index);
+
+out:
+ /*
+ * Return index (f_pos) of the looked up metadata block. Translate
+ * from internal f_pos to external f_pos which is offset by 3 because
+ * we invent "." and ".." entries which are not actually stored in the
+ * directory.
+ */
+ return length + 3;
+}
+
+
+struct dentry *d_splice_alias(struct inode *inode, struct dentry *dentry)
+{
+ struct dentry *de = malloc(sizeof(struct dentry));
+ if (de == NULL) {
+ ERROR("Error allocating dentry\n");
+ return NULL;
+ }
+
+ de->d_inode = inode;
+ de->d_name.name = dentry->d_name.name;
+ de->d_name.len = dentry->d_name.len;
+
+ return de;
+}
+
+struct dentry *squashfs_lookup(struct inode *dir, struct dentry *dentry,
+ unsigned int flags)
+{
+ const unsigned char *name = dentry->d_name.name;
+ int len = dentry->d_name.len;
+ struct inode *inode = NULL;
+ struct squashfs_sb_info *msblk = dir->i_sb->s_fs_info;
+ struct squashfs_dir_header dirh;
+ struct squashfs_dir_entry *dire;
+ u64 block = squashfs_i(dir)->start + msblk->directory_table;
+ int offset = squashfs_i(dir)->offset;
+ int err, length;
+ unsigned int dir_count, size;
+
+ TRACE("Entered squashfs_lookup [%llx:%x]\n", block, offset);
+ dire = kmalloc(sizeof(*dire) + SQUASHFS_NAME_LEN + 1, GFP_KERNEL);
+ if (dire == NULL) {
+ ERROR("Failed to allocate squashfs_dir_entry\n");
+ return ERR_PTR(-ENOMEM);
+ }
+
+ if (len > SQUASHFS_NAME_LEN) {
+ err = -ENAMETOOLONG;
+ goto failed;
+ }
+
+ length = get_dir_index_using_name(dir->i_sb, &block, &offset,
+ squashfs_i(dir)->dir_idx_start,
+ squashfs_i(dir)->dir_idx_offset,
+ squashfs_i(dir)->dir_idx_cnt, name, len);
+
+ while (length < i_size_read(dir)) {
+ /*
+ * Read directory header.
+ */
+ err = squashfs_read_metadata(dir->i_sb, &dirh, &block,
+ &offset, sizeof(dirh));
+ if (err < 0)
+ goto read_failure;
+
+ length += sizeof(dirh);
+
+ dir_count = le32_to_cpu(dirh.count) + 1;
+
+ if (dir_count > SQUASHFS_DIR_COUNT)
+ goto data_error;
+
+ while (dir_count--) {
+ /*
+ * Read directory entry.
+ */
+ err = squashfs_read_metadata(dir->i_sb, dire, &block,
+ &offset, sizeof(*dire));
+ if (err < 0)
+ goto read_failure;
+
+ size = le16_to_cpu(dire->size) + 1;
+
+ /* size should never be larger than SQUASHFS_NAME_LEN */
+ if (size > SQUASHFS_NAME_LEN)
+ goto data_error;
+
+ err = squashfs_read_metadata(dir->i_sb, dire->name,
+ &block, &offset, size);
+ if (err < 0)
+ goto read_failure;
+
+ length += sizeof(*dire) + size;
+ dire->name[len] = '\0';
+ if (name[0] < dire->name[0])
+ goto exit_lookup;
+
+ if (len == size && !strncmp(name, dire->name, len)) {
+ unsigned int blk, off, ino_num;
+ long long ino;
+ blk = le32_to_cpu(dirh.start_block);
+ off = le16_to_cpu(dire->offset);
+ ino_num = le32_to_cpu(dirh.inode_number) +
+ (short) le16_to_cpu(dire->inode_number);
+ ino = SQUASHFS_MKINODE(blk, off);
+
+ TRACE("calling squashfs_iget for directory "
+ "entry %s, inode %x:%x, %d\n", name,
+ blk, off, ino_num);
+
+ inode = squashfs_iget(dir->i_sb, ino, ino_num);
+ goto exit_lookup;
+ }
+ }
+ }
+
+exit_lookup:
+ kfree(dire);
+ return d_splice_alias(inode, dentry);
+
+data_error:
+ err = -EIO;
+
+read_failure:
+ ERROR("Unable to read directory block [%llx:%x]\n",
+ squashfs_i(dir)->start + msblk->directory_table,
+ squashfs_i(dir)->offset);
+failed:
+ kfree(dire);
+ return ERR_PTR(err);
+}
+
+struct dentry *squashfs_lookup_next(struct inode *dir, struct dentry *dentry,
+ struct qstr *cur_name)
+{
+ const unsigned char *name = dentry->d_name.name;
+ int len = dentry->d_name.len;
+ struct inode *inode = NULL;
+ struct squashfs_sb_info *msblk = dir->i_sb->s_fs_info;
+ struct squashfs_dir_header dirh;
+ struct squashfs_dir_entry *dire;
+ u64 block = squashfs_i(dir)->start + msblk->directory_table;
+ int offset = squashfs_i(dir)->offset;
+ int err, length;
+ unsigned int dir_count, size;
+ int name_found = 0;
+ struct dentry *new_dentry = NULL;
+
+ TRACE("Entered squashfs_lookup_next [%llx:%x]\n", block, offset);
+
+ dire = kmalloc(sizeof(*dire) + SQUASHFS_NAME_LEN + 1, GFP_KERNEL);
+ if (dire == NULL) {
+ ERROR("Failed to allocate squashfs_dir_entry\n");
+ return NULL;
+ }
+
+ if (len > SQUASHFS_NAME_LEN) {
+ err = -ENAMETOOLONG;
+ goto failed;
+ }
+
+ length = get_dir_index_using_name(dir->i_sb, &block, &offset,
+ squashfs_i(dir)->dir_idx_start,
+ squashfs_i(dir)->dir_idx_offset,
+ squashfs_i(dir)->dir_idx_cnt, name, len);
+
+ while (length < i_size_read(dir)) {
+ /*
+ * Read directory header.
+ */
+ err = squashfs_read_metadata(dir->i_sb, &dirh, &block,
+ &offset, sizeof(dirh));
+ if (err < 0)
+ goto read_failure;
+
+ length += sizeof(dirh);
+
+ dir_count = le32_to_cpu(dirh.count) + 1;
+
+ if (dir_count > SQUASHFS_DIR_COUNT)
+ goto data_error;
+
+ while (dir_count--) {
+ /*
+ * Read directory entry.
+ */
+ err = squashfs_read_metadata(dir->i_sb, dire, &block,
+ &offset, sizeof(*dire));
+ if (err < 0)
+ goto read_failure;
+
+ size = le16_to_cpu(dire->size) + 1;
+
+ /* size should never be larger than SQUASHFS_NAME_LEN */
+ if (size > SQUASHFS_NAME_LEN)
+ goto data_error;
+
+ err = squashfs_read_metadata(dir->i_sb, dire->name,
+ &block, &offset, size);
+ if (err < 0)
+ goto read_failure;
+
+ length += sizeof(*dire) + size;
+ dire->name[size] = '\0';
+
+ if (cur_name->name[0] == '/')
+ name_found = 1;
+
+ if (!strcmp(cur_name->name, name))
+ name_found = 1;
+
+ if (cur_name->name[0] != '/'
+ && cur_name->len == size
+ && !strncmp(cur_name->name, dire->name, size)) {
+ name_found = 1;
+ continue;
+ }
+
+ if (name_found) {
+ unsigned int blk, off, ino_num;
+ long long ino;
+ char *tmp_name;
+ blk = le32_to_cpu(dirh.start_block);
+ off = le16_to_cpu(dire->offset);
+ ino_num = le32_to_cpu(dirh.inode_number) +
+ (short) le16_to_cpu(dire->inode_number);
+ ino = SQUASHFS_MKINODE(blk, off);
+
+ TRACE("calling squashfs_iget for directory "
+ "entry %s, inode %x:%x, %d\n",
+ dire->name, blk, off, ino_num);
+
+ inode = squashfs_iget(dir->i_sb, ino, ino_num);
+ tmp_name = malloc(size + 1);
+ sprintf(tmp_name, "%s", dire->name);
+ new_dentry = malloc(sizeof(struct dentry));
+ new_dentry->d_name.name = tmp_name;
+ new_dentry->d_name.len = strlen(tmp_name);
+ new_dentry->d_inode = inode;
+ goto exit_lookup;
+ }
+ }
+ }
+
+exit_lookup:
+ kfree(dire);
+ return new_dentry;
+
+data_error:
+ err = -EIO;
+
+read_failure:
+ ERROR("Unable to read directory block [%llx:%x]\n",
+ squashfs_i(dir)->start + msblk->directory_table,
+ squashfs_i(dir)->offset);
+failed:
+ kfree(dire);
+ return new_dentry;
+}
diff --git a/fs/squashfs/page_actor.c b/fs/squashfs/page_actor.c
new file mode 100644
index 0000000..4eb7308
--- /dev/null
+++ b/fs/squashfs/page_actor.c
@@ -0,0 +1,99 @@
+/*
+ * Copyright (c) 2013
+ * Phillip Lougher <phillip at squashfs.org.uk>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2. See
+ * the COPYING file in the top-level directory.
+ */
+
+#include <linux/kernel.h>
+#include <linux/pagemap.h>
+#include "page_actor.h"
+
+/*
+ * This file contains implementations of page_actor for decompressing into
+ * an intermediate buffer, and for decompressing directly into the
+ * page cache.
+ *
+ * Calling code should avoid sleeping between calls to squashfs_first_page()
+ * and squashfs_finish_page().
+ */
+
+/* Implementation of page_actor for decompressing into intermediate buffer */
+static void *cache_first_page(struct squashfs_page_actor *actor)
+{
+ actor->next_page = 1;
+ return actor->buffer[0];
+}
+
+static void *cache_next_page(struct squashfs_page_actor *actor)
+{
+ if (actor->next_page == actor->pages)
+ return NULL;
+
+ return actor->buffer[actor->next_page++];
+}
+
+static void cache_finish_page(struct squashfs_page_actor *actor)
+{
+ /* empty */
+}
+
+struct squashfs_page_actor *squashfs_page_actor_init(void **buffer,
+ int pages, int length)
+{
+ struct squashfs_page_actor *actor = kmalloc(sizeof(*actor), GFP_KERNEL);
+
+ if (actor == NULL)
+ return NULL;
+
+ actor->length = length ? : pages * PAGE_CACHE_SIZE;
+ actor->buffer = buffer;
+ actor->pages = pages;
+ actor->next_page = 0;
+ actor->squashfs_first_page = cache_first_page;
+ actor->squashfs_next_page = cache_next_page;
+ actor->squashfs_finish_page = cache_finish_page;
+ return actor;
+}
+
+/* Implementation of page_actor for decompressing directly into page cache. */
+static void *direct_first_page(struct squashfs_page_actor *actor)
+{
+ actor->next_page = 1;
+ return actor->pageaddr = kmap_atomic(actor->page[0]);
+}
+
+static void *direct_next_page(struct squashfs_page_actor *actor)
+{
+ if (actor->pageaddr)
+ kunmap_atomic(actor->pageaddr);
+
+ return actor->pageaddr = actor->next_page == actor->pages ? NULL :
+ kmap_atomic(actor->page[actor->next_page++]);
+}
+
+static void direct_finish_page(struct squashfs_page_actor *actor)
+{
+ if (actor->pageaddr)
+ kunmap_atomic(actor->pageaddr);
+}
+
+struct squashfs_page_actor *squashfs_page_actor_init_special(struct page **page,
+ int pages, int length)
+{
+ struct squashfs_page_actor *actor = kmalloc(sizeof(*actor), GFP_KERNEL);
+
+ if (actor == NULL)
+ return NULL;
+
+ actor->length = length ? : pages * PAGE_CACHE_SIZE;
+ actor->page = page;
+ actor->pages = pages;
+ actor->next_page = 0;
+ actor->pageaddr = NULL;
+ actor->squashfs_first_page = direct_first_page;
+ actor->squashfs_next_page = direct_next_page;
+ actor->squashfs_finish_page = direct_finish_page;
+ return actor;
+}
diff --git a/fs/squashfs/page_actor.h b/fs/squashfs/page_actor.h
new file mode 100644
index 0000000..c07f05f
--- /dev/null
+++ b/fs/squashfs/page_actor.h
@@ -0,0 +1,53 @@
+#ifndef PAGE_ACTOR_H
+#define PAGE_ACTOR_H
+/*
+ * Copyright (c) 2013
+ * Phillip Lougher <phillip at squashfs.org.uk>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2. See
+ * the COPYING file in the top-level directory.
+ */
+
+#include <malloc.h>
+#include <linux/barebox-wrapper.h>
+#include <linux/pagemap.h>
+
+struct squashfs_page_actor {
+ void **page;
+ int pages;
+ int length;
+ int next_page;
+};
+
+static inline struct squashfs_page_actor *squashfs_page_actor_init(void **page,
+ int pages, int length)
+{
+ struct squashfs_page_actor *actor = kmalloc(sizeof(*actor), GFP_KERNEL);
+
+ if (actor == NULL)
+ return NULL;
+
+ actor->length = length ? : pages * PAGE_CACHE_SIZE;
+ actor->page = page;
+ actor->pages = pages;
+ actor->next_page = 0;
+ return actor;
+}
+
+static inline void *squashfs_first_page(struct squashfs_page_actor *actor)
+{
+ actor->next_page = 1;
+ return actor->page[0];
+}
+
+static inline void *squashfs_next_page(struct squashfs_page_actor *actor)
+{
+ return actor->next_page == actor->pages ? NULL :
+ actor->page[actor->next_page++];
+}
+
+static inline void squashfs_finish_page(struct squashfs_page_actor *actor)
+{
+ /* empty */
+}
+#endif
diff --git a/fs/squashfs/squashfs.c b/fs/squashfs/squashfs.c
new file mode 100644
index 0000000..3b46817
--- /dev/null
+++ b/fs/squashfs/squashfs.c
@@ -0,0 +1,356 @@
+#include <common.h>
+#include <malloc.h>
+#include <driver.h>
+#include <init.h>
+#include <errno.h>
+#include <fs.h>
+#include <xfuncs.h>
+
+#include <linux/fs.h>
+#include <linux/stat.h>
+#include <linux/pagemap.h>
+
+#include "squashfs_fs.h"
+#include "squashfs_fs_sb.h"
+#include "squashfs_fs_i.h"
+#include "squashfs.h"
+
+char *squashfs_devread(struct squashfs_sb_info *fs, int byte_offset,
+ int byte_len)
+{
+ ssize_t size;
+ char *buf;
+
+ buf = malloc(byte_len);
+ if (buf == NULL)
+ return NULL;
+
+ size = cdev_read(fs->cdev, buf, byte_len, byte_offset, 0);
+ if (size < 0) {
+ dev_err(fs->dev, "read error: %s\n",
+ strerror(-size));
+ return NULL;
+ }
+
+ return buf;
+}
+
+struct squashfs_priv {
+ struct super_block *sb;
+};
+
+static struct dentry *squashfs_findfile(struct super_block *sb,
+ const char *filename)
+{
+ char *next;
+ char fpath[128];
+ char *name = fpath;
+ struct inode *inode;
+ struct squashfs_inode_info *ei;
+ struct dentry dir1, *dir2;
+
+ strcpy(fpath, filename);
+
+ /* Remove all leading slashes */
+ while (*name == '/')
+ name++;
+
+ /*
+ * Handle root-direcoty ('/')
+ */
+ if (!name || *name == '\0')
+ return sb->s_root;
+
+ ei = malloc(sizeof(struct squashfs_inode_info));
+ if (ei == NULL) {
+ ERROR("Error allocating memory for inode\n");
+ return NULL;
+ }
+ memcpy(ei, squashfs_i(sb->s_root->d_inode),
+ sizeof(struct squashfs_inode_info));
+
+ inode = &ei->vfs_inode;
+
+ for (;;) {
+
+ /* Extract the actual part from the pathname. */
+ next = strchr(name, '/');
+ if (next) {
+ /* Remove all leading slashes. */
+ while (*next == '/')
+ *(next++) = '\0';
+ }
+
+ dir1.d_name.name = name;
+ dir1.d_name.len = strlen(name);
+
+ dir2 = squashfs_lookup(inode, &dir1, 0);
+ if (dir2 == NULL)
+ break;
+
+ /*
+ * Check if directory with this name exists
+ */
+
+ /* Found the node! */
+ if (!next || *next == '\0') {
+ free(ei);
+ return dir2;
+ }
+
+ name = next;
+
+ memcpy(ei, squashfs_i(dir2->d_inode),
+ sizeof(struct squashfs_inode_info));
+ inode = &ei->vfs_inode;
+
+ free(squashfs_i(dir2->d_inode));
+ free(dir2);
+ }
+
+ free(ei);
+ return NULL;
+}
+
+static int squashfs_probe(struct device_d *dev)
+{
+ struct fs_device_d *fsdev;
+ struct squashfs_priv *priv;
+ int ret;
+
+ fsdev = dev_to_fs_device(dev);
+
+ priv = xmalloc(sizeof(struct squashfs_priv));
+ dev->priv = priv;
+
+ ret = fsdev_open_cdev(fsdev);
+ if (ret)
+ goto err_out;
+
+
+ priv->sb = squashfs_mount(fsdev, 0);
+ if (IS_ERR(priv->sb)) {
+ dev_info(dev, "no valid squashfs found\n");
+ ret = PTR_ERR(priv->sb);
+ goto err_out;
+ }
+
+ return 0;
+
+err_out:
+ free(priv);
+
+ return ret;
+}
+
+static void squashfs_remove(struct device_d *dev)
+{
+ struct squashfs_priv *priv = dev->priv;
+
+ squashfs_put_super(priv->sb);
+
+ free(priv->sb);
+
+ free(priv);
+}
+
+static int squashfs_open(struct device_d *dev, FILE *file, const char *filename)
+{
+ struct squashfs_priv *priv = dev->priv;
+ struct dentry *de;
+ struct squashfs_page *page;
+ int i;
+
+ de = squashfs_findfile(priv->sb, filename);
+ if (!de)
+ return -ENOENT;
+
+ page = malloc(sizeof(struct squashfs_page));
+ page->buf = calloc(32, sizeof(*page->buf));
+ for (i = 0; i < 32; i++)
+ page->buf[i] = malloc(PAGE_CACHE_SIZE);
+
+ page->data_block = 0;
+ page->idx = 0;
+ page->real_page.inode = de->d_inode;
+ file->size = de->d_inode->i_size;
+ file->priv = page;
+
+ free(de);
+
+ return 0;
+}
+
+static int squashfs_close(struct device_d *dev, FILE *f)
+{
+ struct squashfs_page *page = f->priv;
+ int i;
+
+ for (i = 0; i < 32; i++)
+ free(page->buf[i]);
+
+ free(page->buf);
+ free(squashfs_i(page->real_page.inode));
+ free(page);
+
+ return 0;
+}
+
+static int squashfs_read(struct device_d *_dev, FILE *f, void *buf,
+ size_t insize)
+{
+ unsigned int size = insize;
+ int offset, idx;
+ int data_block_pos;
+ struct squashfs_page *page = f->priv;
+
+ if (f->pos >= (page->data_block + 1) * 32 * PAGE_CACHE_SIZE) {
+ page->data_block++;
+ page->idx = 0;
+ }
+
+ data_block_pos = f->pos - page->data_block * 32 * PAGE_CACHE_SIZE;
+ idx = data_block_pos / PAGE_CACHE_SIZE;
+ page->real_page.index = (page->data_block)*32;
+ offset = data_block_pos - idx * PAGE_CACHE_SIZE;
+
+ if (page->idx == 0)
+ squashfs_readpage(NULL, &page->real_page);
+
+ memcpy(buf, page->buf[idx] + offset, size);
+
+ return insize;
+}
+
+static loff_t squashfs_lseek(struct device_d *dev, FILE *f, loff_t pos)
+{
+ f->pos = pos;
+
+ return pos;
+}
+
+struct squashfs_dir {
+ struct file file;
+ struct dentry dentry;
+ struct dentry root_dentry;
+ struct inode inode;
+ struct qstr nm;
+ DIR dir;
+};
+
+static DIR *squashfs_opendir(struct device_d *dev, const char *pathname)
+{
+ struct squashfs_priv *priv = dev->priv;
+ struct file *file;
+ struct dentry *de;
+ struct inode *inode = NULL;
+ unsigned long inum;
+ struct squashfs_dir *dir;
+
+ de = squashfs_findfile(priv->sb, pathname);
+ if (!de)
+ return NULL;
+
+ dir = xzalloc(sizeof(struct squashfs_dir));
+ dir->dir.priv = dir;
+
+ inum = de->d_inode->i_ino;
+
+ file = &dir->file;
+ memcpy(&dir->dentry, de, sizeof(struct dentry));
+ memcpy(&dir->root_dentry, de, sizeof(struct dentry));
+ dir->dentry.d_name.name = malloc(de->d_name.len);
+ dir->root_dentry.d_name.name = malloc(de->d_name.len);
+ sprintf(dir->dentry.d_name.name, "%s", de->d_name.name);
+ sprintf(dir->root_dentry.d_name.name, "%s", de->d_name.name);
+ dir->dentry.d_name.len = de->d_name.len;
+ dir->root_dentry.d_name.len = de->d_name.len;
+
+ inode = &dir->inode;
+
+ file->f_path.dentry = &dir->dentry;
+ file->f_path.dentry->d_parent = &dir->dentry;
+ file->f_path.dentry->d_inode = inode;
+ file->f_path.dentry->d_inode->i_ino = inum;
+ file->f_pos = 1;
+
+ return &dir->dir;
+}
+static struct dirent *squashfs_readdir(struct device_d *dev, DIR *_dir)
+{
+ struct squashfs_dir *dir = _dir->priv;
+ struct dentry *dentry = &dir->dentry;
+ struct dentry *root_dentry = &dir->root_dentry;
+ struct dentry *de;
+ struct qstr nm;
+
+ nm.name = malloc(dentry->d_name.len);
+ sprintf(nm.name, "%s", dentry->d_name.name);
+ nm.len = dentry->d_name.len;
+
+ de = squashfs_lookup_next(root_dentry->d_inode, root_dentry, &nm);
+ if (de == NULL) {
+ free(nm.name);
+ return NULL;
+ }
+
+ memcpy(&dir->dentry, de, sizeof(struct dentry));
+ strcpy(_dir->d.d_name, de->d_name.name);
+
+ free(squashfs_i(de->d_inode));
+ free(de);
+ free(nm.name);
+
+ return &_dir->d;
+}
+
+static int squashfs_closedir(struct device_d *dev, DIR *_dir)
+{
+ struct squashfs_dir *dir = _dir->priv;
+
+ free(dir);
+
+ return 0;
+}
+
+static int squashfs_stat(struct device_d *dev, const char *filename,
+ struct stat *s)
+{
+ struct squashfs_priv *priv = dev->priv;
+ struct dentry *dentry;
+
+ dentry = squashfs_findfile(priv->sb, filename);
+ if (!dentry)
+ return -ENOENT;
+
+ s->st_size = dentry->d_inode->i_size;
+ s->st_mode = dentry->d_inode->i_mode;
+
+ free(squashfs_i(dentry->d_inode));
+ free(dentry);
+
+ return 0;
+}
+
+static struct fs_driver_d squashfs_driver = {
+ .open = squashfs_open,
+ .close = squashfs_close,
+ .read = squashfs_read,
+ .lseek = squashfs_lseek,
+ .opendir = squashfs_opendir,
+ .readdir = squashfs_readdir,
+ .closedir = squashfs_closedir,
+ .stat = squashfs_stat,
+ .drv = {
+ .probe = squashfs_probe,
+ .remove = squashfs_remove,
+ .name = "squashfs",
+ }
+};
+
+static int squashfs_init(void)
+{
+ return register_fs_driver(&squashfs_driver);
+}
+
+device_initcall(squashfs_init);
diff --git a/fs/squashfs/squashfs.h b/fs/squashfs/squashfs.h
new file mode 100644
index 0000000..956a61a
--- /dev/null
+++ b/fs/squashfs/squashfs.h
@@ -0,0 +1,138 @@
+/*
+ * Squashfs - a compressed read only filesystem for Linux
+ *
+ * Copyright (c) 2002, 2003, 2004, 2005, 2006, 2007, 2008
+ * Phillip Lougher <phillip at squashfs.org.uk>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2,
+ * or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * squashfs.h
+ */
+
+#include <printk.h>
+#include <fs.h>
+#include <linux/fs.h>
+#include <linux/kernel.h>
+
+#define DEBUG
+#define pgoff_t unsigned long
+
+/*
+ * We "simulate" the Linux page struct much simpler here
+ */
+struct page {
+ pgoff_t index;
+ void *addr;
+ struct inode *inode;
+};
+
+
+struct squashfs_page {
+ struct page real_page;
+ char **buf;
+ int idx;
+ int data_block;
+};
+
+static inline struct squashfs_page *squashfs_page(struct page *page)
+{
+ return container_of(page, struct squashfs_page, real_page);
+}
+#define TRACE(s, args...) pr_debug("SQUASHFS: "s, ## args)
+
+#define ERROR(s, args...) pr_err("SQUASHFS error: "s, ## args)
+
+#define WARNING(s, args...) pr_warn("SQUASHFS: "s, ## args)
+
+struct inode *iget_locked_squashfs(struct super_block *sb, unsigned long ino);
+char *squashfs_devread(struct squashfs_sb_info *fs, int byte_offset,
+ int byte_len);
+extern struct super_block *squashfs_mount(struct fs_device_d *fsdev,
+ int silent);
+extern void squashfs_put_super(struct super_block *sb);
+
+/* block.c */
+extern int squashfs_read_data(struct super_block *, u64, int, u64 *,
+ struct squashfs_page_actor *);
+
+/* cache.c */
+extern struct squashfs_cache *squashfs_cache_init(char *, int, int);
+extern void squashfs_cache_delete(struct squashfs_cache *);
+extern struct squashfs_cache_entry *squashfs_cache_get(struct super_block *,
+ struct squashfs_cache *, u64, int);
+extern void squashfs_cache_put(struct squashfs_cache_entry *);
+extern int squashfs_copy_data(void *, struct squashfs_cache_entry *, int, int);
+extern int squashfs_read_metadata(struct super_block *, void *, u64 *,
+ int *, int);
+extern struct squashfs_cache_entry *squashfs_get_fragment(struct super_block *,
+ u64, int);
+extern struct squashfs_cache_entry *squashfs_get_datablock(struct super_block *,
+ u64, int);
+extern void *squashfs_read_table(struct super_block *, u64, int);
+
+/* decompressor.c */
+extern const struct squashfs_decompressor *squashfs_lookup_decompressor(int);
+extern void *squashfs_decompressor_setup(struct super_block *, unsigned short);
+
+/* decompressor_xxx.c */
+extern void *squashfs_decompressor_create(struct squashfs_sb_info *, void *);
+extern void squashfs_decompressor_destroy(struct squashfs_sb_info *);
+extern int squashfs_decompress(struct squashfs_sb_info *, char **,
+ int, int, int, struct squashfs_page_actor *);
+extern int squashfs_max_decompressors(void);
+
+/* fragment.c */
+extern int squashfs_frag_lookup(struct super_block *, unsigned int, u64 *);
+extern __le64 *squashfs_read_fragment_index_table(struct super_block *,
+ u64, u64, unsigned int);
+/* file.c */
+void squashfs_copy_cache(struct page *, struct squashfs_cache_entry *, int,
+ int);
+extern int squashfs_readpage(struct file *file, struct page *page);
+
+/* file_xxx.c */
+extern int squashfs_readpage_block(struct page *, u64, int);
+
+/* id.c */
+extern int squashfs_get_id(struct super_block *, unsigned int, unsigned int *);
+extern __le64 *squashfs_read_id_index_table(struct super_block *, u64, u64,
+ unsigned short);
+
+/* inode.c */
+extern struct inode *squashfs_iget(struct super_block *, long long,
+ unsigned int);
+extern int squashfs_read_inode(struct inode *, long long);
+
+/*
+ * Inodes, files, decompressor and xattr operations
+ */
+
+/* dir.c */
+extern const struct file_operations squashfs_dir_ops;
+
+/* export.c */
+extern const struct export_operations squashfs_export_ops;
+
+/* file.c */
+extern const struct address_space_operations squashfs_aops;
+
+/* inode.c */
+extern const struct inode_operations squashfs_inode_ops;
+
+/* namei.c */
+extern struct dentry *squashfs_lookup(struct inode *dir, struct dentry *dentry,
+ unsigned int flags);
+extern struct dentry *squashfs_lookup_next(struct inode *dir,
+ struct dentry *dentry, struct qstr *cur_name);
+
+/* symlink.c */
+extern const struct address_space_operations squashfs_symlink_aops;
+extern const struct inode_operations squashfs_symlink_inode_ops;
diff --git a/fs/squashfs/squashfs_fs.h b/fs/squashfs/squashfs_fs.h
new file mode 100644
index 0000000..56e7285
--- /dev/null
+++ b/fs/squashfs/squashfs_fs.h
@@ -0,0 +1,453 @@
+#ifndef SQUASHFS_FS
+#define SQUASHFS_FS
+/*
+ * Squashfs
+ *
+ * Copyright (c) 2002, 2003, 2004, 2005, 2006, 2007, 2008
+ * Phillip Lougher <phillip at squashfs.org.uk>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2,
+ * or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * squashfs_fs.h
+ */
+
+#define SQUASHFS_CACHED_FRAGMENTS 3
+#define SQUASHFS_MAJOR 4
+#define SQUASHFS_MINOR 0
+#define SQUASHFS_START 0
+
+/* size of metadata (inode and directory) blocks */
+#define SQUASHFS_METADATA_SIZE 8192
+
+/* default size of block device I/O */
+#ifdef CONFIG_SQUASHFS_4K_DEVBLK_SIZE
+#define SQUASHFS_DEVBLK_SIZE 4096
+#else
+#define SQUASHFS_DEVBLK_SIZE 1024
+#endif
+
+#define SQUASHFS_FILE_MAX_SIZE 1048576
+#define SQUASHFS_FILE_MAX_LOG 20
+
+/* Max length of filename (not 255) */
+#define SQUASHFS_NAME_LEN 256
+
+/* Max value for directory header count*/
+#define SQUASHFS_DIR_COUNT 256
+
+#define SQUASHFS_INVALID_FRAG (0xffffffffU)
+#define SQUASHFS_INVALID_XATTR (0xffffffffU)
+#define SQUASHFS_INVALID_BLK (-1LL)
+
+/* Filesystem flags */
+#define SQUASHFS_NOI 0
+#define SQUASHFS_NOD 1
+#define SQUASHFS_NOF 3
+#define SQUASHFS_NO_FRAG 4
+#define SQUASHFS_ALWAYS_FRAG 5
+#define SQUASHFS_DUPLICATE 6
+#define SQUASHFS_EXPORT 7
+#define SQUASHFS_COMP_OPT 10
+
+#define SQUASHFS_BIT(flag, bit) ((flag >> bit) & 1)
+
+#define SQUASHFS_UNCOMPRESSED_INODES(flags) SQUASHFS_BIT(flags, \
+ SQUASHFS_NOI)
+
+#define SQUASHFS_UNCOMPRESSED_DATA(flags) SQUASHFS_BIT(flags, \
+ SQUASHFS_NOD)
+
+#define SQUASHFS_UNCOMPRESSED_FRAGMENTS(flags) SQUASHFS_BIT(flags, \
+ SQUASHFS_NOF)
+
+#define SQUASHFS_NO_FRAGMENTS(flags) SQUASHFS_BIT(flags, \
+ SQUASHFS_NO_FRAG)
+
+#define SQUASHFS_ALWAYS_FRAGMENTS(flags) SQUASHFS_BIT(flags, \
+ SQUASHFS_ALWAYS_FRAG)
+
+#define SQUASHFS_DUPLICATES(flags) SQUASHFS_BIT(flags, \
+ SQUASHFS_DUPLICATE)
+
+#define SQUASHFS_EXPORTABLE(flags) SQUASHFS_BIT(flags, \
+ SQUASHFS_EXPORT)
+
+#define SQUASHFS_COMP_OPTS(flags) SQUASHFS_BIT(flags, \
+ SQUASHFS_COMP_OPT)
+
+/* Inode types including extended types */
+#define SQUASHFS_DIR_TYPE 1
+#define SQUASHFS_REG_TYPE 2
+#define SQUASHFS_SYMLINK_TYPE 3
+#define SQUASHFS_BLKDEV_TYPE 4
+#define SQUASHFS_CHRDEV_TYPE 5
+#define SQUASHFS_FIFO_TYPE 6
+#define SQUASHFS_SOCKET_TYPE 7
+#define SQUASHFS_LDIR_TYPE 8
+#define SQUASHFS_LREG_TYPE 9
+#define SQUASHFS_LSYMLINK_TYPE 10
+#define SQUASHFS_LBLKDEV_TYPE 11
+#define SQUASHFS_LCHRDEV_TYPE 12
+#define SQUASHFS_LFIFO_TYPE 13
+#define SQUASHFS_LSOCKET_TYPE 14
+
+/* Max type value stored in directory entry */
+#define SQUASHFS_MAX_DIR_TYPE 7
+
+/* Xattr types */
+#define SQUASHFS_XATTR_USER 0
+#define SQUASHFS_XATTR_TRUSTED 1
+#define SQUASHFS_XATTR_SECURITY 2
+#define SQUASHFS_XATTR_VALUE_OOL 256
+#define SQUASHFS_XATTR_PREFIX_MASK 0xff
+
+/* Flag whether block is compressed or uncompressed, bit is set if block is
+ * uncompressed */
+#define SQUASHFS_COMPRESSED_BIT (1 << 15)
+
+#define SQUASHFS_COMPRESSED_SIZE(B) (((B) & ~SQUASHFS_COMPRESSED_BIT) ? \
+ (B) & ~SQUASHFS_COMPRESSED_BIT : SQUASHFS_COMPRESSED_BIT)
+
+#define SQUASHFS_COMPRESSED(B) (!((B) & SQUASHFS_COMPRESSED_BIT))
+
+#define SQUASHFS_COMPRESSED_BIT_BLOCK (1 << 24)
+
+#define SQUASHFS_COMPRESSED_SIZE_BLOCK(B) ((B) & \
+ ~SQUASHFS_COMPRESSED_BIT_BLOCK)
+
+#define SQUASHFS_COMPRESSED_BLOCK(B) (!((B) & SQUASHFS_COMPRESSED_BIT_BLOCK))
+
+/*
+ * Inode number ops. Inodes consist of a compressed block number, and an
+ * uncompressed offset within that block
+ */
+#define SQUASHFS_INODE_BLK(A) ((unsigned int) ((A) >> 16))
+
+#define SQUASHFS_INODE_OFFSET(A) ((unsigned int) ((A) & 0xffff))
+
+#define SQUASHFS_MKINODE(A, B) ((long long)(((long long) (A)\
+ << 16) + (B)))
+
+/* fragment and fragment table defines */
+#define SQUASHFS_FRAGMENT_BYTES(A) \
+ ((A) * sizeof(struct squashfs_fragment_entry))
+
+#define SQUASHFS_FRAGMENT_INDEX(A) (SQUASHFS_FRAGMENT_BYTES(A) / \
+ SQUASHFS_METADATA_SIZE)
+
+#define SQUASHFS_FRAGMENT_INDEX_OFFSET(A) (SQUASHFS_FRAGMENT_BYTES(A) % \
+ SQUASHFS_METADATA_SIZE)
+
+#define SQUASHFS_FRAGMENT_INDEXES(A) ((SQUASHFS_FRAGMENT_BYTES(A) + \
+ SQUASHFS_METADATA_SIZE - 1) / \
+ SQUASHFS_METADATA_SIZE)
+
+#define SQUASHFS_FRAGMENT_INDEX_BYTES(A) (SQUASHFS_FRAGMENT_INDEXES(A) *\
+ sizeof(u64))
+
+/* inode lookup table defines */
+#define SQUASHFS_LOOKUP_BYTES(A) ((A) * sizeof(u64))
+
+#define SQUASHFS_LOOKUP_BLOCK(A) (SQUASHFS_LOOKUP_BYTES(A) / \
+ SQUASHFS_METADATA_SIZE)
+
+#define SQUASHFS_LOOKUP_BLOCK_OFFSET(A) (SQUASHFS_LOOKUP_BYTES(A) % \
+ SQUASHFS_METADATA_SIZE)
+
+#define SQUASHFS_LOOKUP_BLOCKS(A) ((SQUASHFS_LOOKUP_BYTES(A) + \
+ SQUASHFS_METADATA_SIZE - 1) / \
+ SQUASHFS_METADATA_SIZE)
+
+#define SQUASHFS_LOOKUP_BLOCK_BYTES(A) (SQUASHFS_LOOKUP_BLOCKS(A) *\
+ sizeof(u64))
+
+/* uid/gid lookup table defines */
+#define SQUASHFS_ID_BYTES(A) ((A) * sizeof(unsigned int))
+
+#define SQUASHFS_ID_BLOCK(A) (SQUASHFS_ID_BYTES(A) / \
+ SQUASHFS_METADATA_SIZE)
+
+#define SQUASHFS_ID_BLOCK_OFFSET(A) (SQUASHFS_ID_BYTES(A) % \
+ SQUASHFS_METADATA_SIZE)
+
+#define SQUASHFS_ID_BLOCKS(A) ((SQUASHFS_ID_BYTES(A) + \
+ SQUASHFS_METADATA_SIZE - 1) / \
+ SQUASHFS_METADATA_SIZE)
+
+#define SQUASHFS_ID_BLOCK_BYTES(A) (SQUASHFS_ID_BLOCKS(A) *\
+ sizeof(u64))
+/* xattr id lookup table defines */
+#define SQUASHFS_XATTR_BYTES(A) ((A) * sizeof(struct squashfs_xattr_id))
+
+#define SQUASHFS_XATTR_BLOCK(A) (SQUASHFS_XATTR_BYTES(A) / \
+ SQUASHFS_METADATA_SIZE)
+
+#define SQUASHFS_XATTR_BLOCK_OFFSET(A) (SQUASHFS_XATTR_BYTES(A) % \
+ SQUASHFS_METADATA_SIZE)
+
+#define SQUASHFS_XATTR_BLOCKS(A) ((SQUASHFS_XATTR_BYTES(A) + \
+ SQUASHFS_METADATA_SIZE - 1) / \
+ SQUASHFS_METADATA_SIZE)
+
+#define SQUASHFS_XATTR_BLOCK_BYTES(A) (SQUASHFS_XATTR_BLOCKS(A) *\
+ sizeof(u64))
+#define SQUASHFS_XATTR_BLK(A) ((unsigned int) ((A) >> 16))
+
+#define SQUASHFS_XATTR_OFFSET(A) ((unsigned int) ((A) & 0xffff))
+
+/* cached data constants for filesystem */
+#define SQUASHFS_CACHED_BLKS 8
+
+/* meta index cache */
+#define SQUASHFS_META_INDEXES (SQUASHFS_METADATA_SIZE / sizeof(unsigned int))
+#define SQUASHFS_META_ENTRIES 127
+#define SQUASHFS_META_SLOTS 8
+
+struct meta_entry {
+ u64 data_block;
+ unsigned int index_block;
+ unsigned short offset;
+ unsigned short pad;
+};
+
+struct meta_index {
+ unsigned int inode_number;
+ unsigned int offset;
+ unsigned short entries;
+ unsigned short skip;
+ unsigned short locked;
+ unsigned short pad;
+ struct meta_entry meta_entry[SQUASHFS_META_ENTRIES];
+};
+
+
+/*
+ * definitions for structures on disk
+ */
+#define ZLIB_COMPRESSION 1
+#define LZMA_COMPRESSION 2
+#define LZO_COMPRESSION 3
+#define XZ_COMPRESSION 4
+#define LZ4_COMPRESSION 5
+
+struct squashfs_super_block {
+ __le32 s_magic;
+ __le32 inodes;
+ __le32 mkfs_time;
+ __le32 block_size;
+ __le32 fragments;
+ __le16 compression;
+ __le16 block_log;
+ __le16 flags;
+ __le16 no_ids;
+ __le16 s_major;
+ __le16 s_minor;
+ __le64 root_inode;
+ __le64 bytes_used;
+ __le64 id_table_start;
+ __le64 xattr_id_table_start;
+ __le64 inode_table_start;
+ __le64 directory_table_start;
+ __le64 fragment_table_start;
+ __le64 lookup_table_start;
+};
+
+struct squashfs_dir_index {
+ __le32 index;
+ __le32 start_block;
+ __le32 size;
+ unsigned char name[0];
+};
+
+struct squashfs_base_inode {
+ __le16 inode_type;
+ __le16 mode;
+ __le16 uid;
+ __le16 guid;
+ __le32 mtime;
+ __le32 inode_number;
+};
+
+struct squashfs_ipc_inode {
+ __le16 inode_type;
+ __le16 mode;
+ __le16 uid;
+ __le16 guid;
+ __le32 mtime;
+ __le32 inode_number;
+ __le32 nlink;
+};
+
+struct squashfs_lipc_inode {
+ __le16 inode_type;
+ __le16 mode;
+ __le16 uid;
+ __le16 guid;
+ __le32 mtime;
+ __le32 inode_number;
+ __le32 nlink;
+ __le32 xattr;
+};
+
+struct squashfs_dev_inode {
+ __le16 inode_type;
+ __le16 mode;
+ __le16 uid;
+ __le16 guid;
+ __le32 mtime;
+ __le32 inode_number;
+ __le32 nlink;
+ __le32 rdev;
+};
+
+struct squashfs_ldev_inode {
+ __le16 inode_type;
+ __le16 mode;
+ __le16 uid;
+ __le16 guid;
+ __le32 mtime;
+ __le32 inode_number;
+ __le32 nlink;
+ __le32 rdev;
+ __le32 xattr;
+};
+
+struct squashfs_symlink_inode {
+ __le16 inode_type;
+ __le16 mode;
+ __le16 uid;
+ __le16 guid;
+ __le32 mtime;
+ __le32 inode_number;
+ __le32 nlink;
+ __le32 symlink_size;
+ char symlink[0];
+};
+
+struct squashfs_reg_inode {
+ __le16 inode_type;
+ __le16 mode;
+ __le16 uid;
+ __le16 guid;
+ __le32 mtime;
+ __le32 inode_number;
+ __le32 start_block;
+ __le32 fragment;
+ __le32 offset;
+ __le32 file_size;
+ __le16 block_list[0];
+};
+
+struct squashfs_lreg_inode {
+ __le16 inode_type;
+ __le16 mode;
+ __le16 uid;
+ __le16 guid;
+ __le32 mtime;
+ __le32 inode_number;
+ __le64 start_block;
+ __le64 file_size;
+ __le64 sparse;
+ __le32 nlink;
+ __le32 fragment;
+ __le32 offset;
+ __le32 xattr;
+ __le16 block_list[0];
+};
+
+struct squashfs_dir_inode {
+ __le16 inode_type;
+ __le16 mode;
+ __le16 uid;
+ __le16 guid;
+ __le32 mtime;
+ __le32 inode_number;
+ __le32 start_block;
+ __le32 nlink;
+ __le16 file_size;
+ __le16 offset;
+ __le32 parent_inode;
+};
+
+struct squashfs_ldir_inode {
+ __le16 inode_type;
+ __le16 mode;
+ __le16 uid;
+ __le16 guid;
+ __le32 mtime;
+ __le32 inode_number;
+ __le32 nlink;
+ __le32 file_size;
+ __le32 start_block;
+ __le32 parent_inode;
+ __le16 i_count;
+ __le16 offset;
+ __le32 xattr;
+ struct squashfs_dir_index index[0];
+};
+
+union squashfs_inode {
+ struct squashfs_base_inode base;
+ struct squashfs_dev_inode dev;
+ struct squashfs_ldev_inode ldev;
+ struct squashfs_symlink_inode symlink;
+ struct squashfs_reg_inode reg;
+ struct squashfs_lreg_inode lreg;
+ struct squashfs_dir_inode dir;
+ struct squashfs_ldir_inode ldir;
+ struct squashfs_ipc_inode ipc;
+ struct squashfs_lipc_inode lipc;
+};
+
+struct squashfs_dir_entry {
+ __le16 offset;
+ __le16 inode_number;
+ __le16 type;
+ __le16 size;
+ char name[0];
+};
+
+struct squashfs_dir_header {
+ __le32 count;
+ __le32 start_block;
+ __le32 inode_number;
+};
+
+struct squashfs_fragment_entry {
+ __le64 start_block;
+ __le32 size;
+ unsigned int unused;
+};
+
+struct squashfs_xattr_entry {
+ __le16 type;
+ __le16 size;
+ char data[0];
+};
+
+struct squashfs_xattr_val {
+ __le32 vsize;
+ char value[0];
+};
+
+struct squashfs_xattr_id {
+ __le64 xattr;
+ __le32 count;
+ __le32 size;
+};
+
+struct squashfs_xattr_id_table {
+ __le64 xattr_table_start;
+ __le32 xattr_ids;
+ __le32 unused;
+};
+
+#endif
diff --git a/fs/squashfs/squashfs_fs_i.h b/fs/squashfs/squashfs_fs_i.h
new file mode 100644
index 0000000..ad15554
--- /dev/null
+++ b/fs/squashfs/squashfs_fs_i.h
@@ -0,0 +1,52 @@
+#ifndef SQUASHFS_FS_I
+#define SQUASHFS_FS_I
+/*
+ * Squashfs
+ *
+ * Copyright (c) 2002, 2003, 2004, 2005, 2006, 2007, 2008
+ * Phillip Lougher <phillip at squashfs.org.uk>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2,
+ * or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * squashfs_fs_i.h
+ */
+
+#include <linux/kernel.h>
+
+struct squashfs_inode_info {
+ u64 start;
+ int offset;
+ u64 xattr;
+ unsigned int xattr_size;
+ int xattr_count;
+ union {
+ struct {
+ u64 fragment_block;
+ int fragment_size;
+ int fragment_offset;
+ u64 block_list_start;
+ };
+ struct {
+ u64 dir_idx_start;
+ int dir_idx_offset;
+ int dir_idx_cnt;
+ int parent;
+ };
+ };
+ struct inode vfs_inode;
+};
+
+
+static inline struct squashfs_inode_info *squashfs_i(struct inode *inode)
+{
+ return container_of(inode, struct squashfs_inode_info, vfs_inode);
+}
+#endif
diff --git a/fs/squashfs/squashfs_fs_sb.h b/fs/squashfs/squashfs_fs_sb.h
new file mode 100644
index 0000000..2b6f81d
--- /dev/null
+++ b/fs/squashfs/squashfs_fs_sb.h
@@ -0,0 +1,82 @@
+#ifndef SQUASHFS_FS_SB
+#define SQUASHFS_FS_SB
+/*
+ * Squashfs
+ *
+ * Copyright (c) 2002, 2003, 2004, 2005, 2006, 2007, 2008
+ * Phillip Lougher <phillip at squashfs.org.uk>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2,
+ * or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * squashfs_fs_sb.h
+ */
+
+#include <linux/spinlock.h>
+#include <linux/wait.h>
+#include <linux/mutex.h>
+#include <linux/barebox-wrapper.h>
+#include "squashfs_fs.h"
+
+struct squashfs_cache {
+ char *name;
+ int entries;
+ int curr_blk;
+ int next_blk;
+ int num_waiters;
+ int unused;
+ int block_size;
+ int pages;
+ spinlock_t lock;
+ wait_queue_head_t wait_queue;
+ struct squashfs_cache_entry *entry;
+};
+
+struct squashfs_cache_entry {
+ u64 block;
+ int length;
+ int refcount;
+ u64 next_index;
+ int pending;
+ int error;
+ int num_waiters;
+ wait_queue_head_t wait_queue;
+ struct squashfs_cache *cache;
+ void **data;
+ struct squashfs_page_actor *actor;
+};
+
+struct squashfs_sb_info {
+ const struct squashfs_decompressor *decompressor;
+ int devblksize;
+ int devblksize_log2;
+ struct squashfs_cache *block_cache;
+ struct squashfs_cache *fragment_cache;
+ struct squashfs_cache *read_page;
+ int next_meta_index;
+ __le64 *id_table;
+ __le64 *fragment_index;
+ __le64 *xattr_id_table;
+ struct mutex meta_index_mutex;
+ struct meta_index *meta_index;
+ struct squashfs_stream *stream;
+ __le64 *inode_lookup_table;
+ u64 inode_table;
+ u64 directory_table;
+ u64 xattr_table;
+ unsigned int block_size;
+ unsigned short block_log;
+ long long bytes_used;
+ unsigned int inodes;
+ int xattr_ids;
+ struct cdev *cdev;
+ struct device_d *dev;
+};
+#endif
diff --git a/fs/squashfs/super.c b/fs/squashfs/super.c
new file mode 100644
index 0000000..26ed8ca
--- /dev/null
+++ b/fs/squashfs/super.c
@@ -0,0 +1,348 @@
+/*
+ * Squashfs - a compressed read only filesystem for Linux
+ *
+ * Copyright (c) 2002, 2003, 2004, 2005, 2006, 2007, 2008
+ * Phillip Lougher <phillip at squashfs.org.uk>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2,
+ * or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * super.c
+ */
+
+/*
+ * This file implements code to read the superblock, read and initialise
+ * in-memory structures at mount time, and all the VFS glue code to register
+ * the filesystem.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <errno.h>
+#include <linux/fs.h>
+#include <linux/kernel.h>
+#include <linux/pagemap.h>
+#include <linux/magic.h>
+#include <linux/bitops.h>
+
+#include "page_actor.h"
+#include "squashfs_fs.h"
+#include "squashfs_fs_sb.h"
+#include "squashfs_fs_i.h"
+#include "squashfs.h"
+#include "decompressor.h"
+
+struct dentry *d_make_root(struct inode *inode)
+{
+ struct dentry *de = malloc(sizeof(struct dentry));
+ de->d_name.name = "/";
+ de->d_name.len = strlen("/");
+ de->d_inode = inode;
+ return de;
+}
+
+static const struct squashfs_decompressor *supported_squashfs_filesystem(short
+ major, short minor, short id)
+{
+ const struct squashfs_decompressor *decompressor;
+
+ if (major < SQUASHFS_MAJOR) {
+ ERROR("Major/Minor mismatch, older Squashfs %d.%d "
+ "filesystems are unsupported\n", major, minor);
+ return NULL;
+ } else if (major > SQUASHFS_MAJOR || minor > SQUASHFS_MINOR) {
+ ERROR("Major/Minor mismatch, trying to mount newer "
+ "%d.%d filesystem\n", major, minor);
+ ERROR("Please update your kernel\n");
+ return NULL;
+ }
+
+ decompressor = squashfs_lookup_decompressor(id);
+ if (!decompressor->supported) {
+ ERROR("Filesystem uses \"%s\" compression. This is not "
+ "supported\n", decompressor->name);
+ return NULL;
+ }
+
+ return decompressor;
+}
+
+void squashfs_put_super(struct super_block *sb)
+{
+ if (sb->s_fs_info) {
+ struct squashfs_sb_info *sbi = sb->s_fs_info;
+ squashfs_cache_delete(sbi->block_cache);
+ squashfs_cache_delete(sbi->fragment_cache);
+ squashfs_cache_delete(sbi->read_page);
+ squashfs_decompressor_destroy(sbi);
+ kfree(sbi->id_table);
+ kfree(sbi->fragment_index);
+ kfree(sbi->meta_index);
+ kfree(sbi->inode_lookup_table);
+ kfree(sbi->xattr_id_table);
+ kfree(sb->s_fs_info);
+ sb->s_fs_info = NULL;
+ }
+
+ if (sb->s_root) {
+ kfree(squashfs_i(sb->s_root->d_inode));
+ kfree(sb->s_root);
+ sb->s_root = NULL;
+ }
+}
+
+static int squashfs_fill_super(struct super_block *sb, void *data, int silent)
+{
+ struct squashfs_sb_info *msblk;
+ struct fs_device_d *fsdev = (struct fs_device_d *)data;
+ struct squashfs_super_block *sblk = NULL;
+ struct inode *root;
+ long long root_inode;
+ unsigned short flags;
+ unsigned int fragments;
+ u64 lookup_table_start, next_table;
+ int err;
+
+ TRACE("Entered squashfs_fill_superblock\n");
+
+ sb->s_fs_info = kzalloc(sizeof(*msblk), GFP_KERNEL);
+ if (sb->s_fs_info == NULL) {
+ ERROR("Failed to allocate squashfs_sb_info\n");
+ return -ENOMEM;
+ }
+ msblk = sb->s_fs_info;
+ msblk->cdev = fsdev->cdev;
+ msblk->dev = &fsdev->dev;
+
+ msblk->devblksize = 1024;
+ msblk->devblksize_log2 = ffz(~msblk->devblksize);
+
+ mutex_init(&msblk->meta_index_mutex);
+ /*
+ * msblk->bytes_used is checked in squashfs_read_table to ensure reads
+ * are not beyond filesystem end. But as we're using
+ * squashfs_read_table here to read the superblock (including the value
+ * of bytes_used) we need to set it to an initial sensible dummy value
+ */
+ msblk->bytes_used = sizeof(*sblk);
+ sblk = squashfs_read_table(sb, SQUASHFS_START, sizeof(*sblk));
+
+ if (IS_ERR(sblk)) {
+ ERROR("unable to read squashfs_super_block\n");
+ err = PTR_ERR(sblk);
+ sblk = NULL;
+ goto failed_mount;
+ }
+
+ err = -EINVAL;
+
+ /* Check it is a SQUASHFS superblock */
+ sb->s_magic = le32_to_cpu(sblk->s_magic);
+ if (sb->s_magic != SQUASHFS_MAGIC) {
+ if (!silent)
+ ERROR("Can't find a SQUASHFS superblock on %pg\n",
+ sb->s_bdev);
+ goto failed_mount;
+ }
+
+ /* Check the MAJOR & MINOR versions and lookup compression type */
+ msblk->decompressor = supported_squashfs_filesystem(
+ le16_to_cpu(sblk->s_major),
+ le16_to_cpu(sblk->s_minor),
+ le16_to_cpu(sblk->compression));
+ if (msblk->decompressor == NULL)
+ goto failed_mount;
+
+ /* Check the filesystem does not extend beyond the end of the
+ block device */
+ msblk->bytes_used = le64_to_cpu(sblk->bytes_used);
+ if (msblk->bytes_used < 0 || msblk->bytes_used >
+ msblk->cdev->size)
+ goto failed_mount;
+
+ /* Check block size for sanity */
+ msblk->block_size = le32_to_cpu(sblk->block_size);
+ if (msblk->block_size > SQUASHFS_FILE_MAX_SIZE)
+ goto failed_mount;
+
+ /*
+ * Check the system page size is not larger than the filesystem
+ * block size (by default 128K). This is currently not supported.
+ */
+ if (PAGE_CACHE_SIZE > msblk->block_size) {
+ ERROR("Page size > filesystem block size (%d). This is "
+ "currently not supported!\n", msblk->block_size);
+ goto failed_mount;
+ }
+
+ /* Check block log for sanity */
+ msblk->block_log = le16_to_cpu(sblk->block_log);
+ if (msblk->block_log > SQUASHFS_FILE_MAX_LOG)
+ goto failed_mount;
+
+ /* Check that block_size and block_log match */
+ if (msblk->block_size != (1 << msblk->block_log))
+ goto failed_mount;
+
+ /* Check the root inode for sanity */
+ root_inode = le64_to_cpu(sblk->root_inode);
+ if (SQUASHFS_INODE_OFFSET(root_inode) > SQUASHFS_METADATA_SIZE)
+ goto failed_mount;
+
+ msblk->inode_table = le64_to_cpu(sblk->inode_table_start);
+ msblk->directory_table = le64_to_cpu(sblk->directory_table_start);
+ msblk->inodes = le32_to_cpu(sblk->inodes);
+ flags = le16_to_cpu(sblk->flags);
+
+ TRACE("Found valid superblock on %pg\n", sb->s_bdev);
+ TRACE("Inodes are %scompressed\n", SQUASHFS_UNCOMPRESSED_INODES(flags)
+ ? "un" : "");
+ TRACE("Data is %scompressed\n", SQUASHFS_UNCOMPRESSED_DATA(flags)
+ ? "un" : "");
+ TRACE("Filesystem size %lld bytes\n", msblk->bytes_used);
+ TRACE("Block size %d\n", msblk->block_size);
+ TRACE("Number of inodes %d\n", msblk->inodes);
+ TRACE("Number of fragments %d\n", le32_to_cpu(sblk->fragments));
+ TRACE("Number of ids %d\n", le16_to_cpu(sblk->no_ids));
+ TRACE("sblk->inode_table_start %llx\n", msblk->inode_table);
+ TRACE("sblk->directory_table_start %llx\n", msblk->directory_table);
+ TRACE("sblk->fragment_table_start %llx\n",
+ (u64) le64_to_cpu(sblk->fragment_table_start));
+ TRACE("sblk->id_table_start %llx\n",
+ (u64) le64_to_cpu(sblk->id_table_start));
+
+ sb->s_maxbytes = MAX_LFS_FILESIZE;
+ sb->s_flags |= MS_RDONLY;
+
+ err = -ENOMEM;
+
+ msblk->block_cache = squashfs_cache_init("metadata",
+ SQUASHFS_CACHED_BLKS, SQUASHFS_METADATA_SIZE);
+ if (msblk->block_cache == NULL)
+ goto failed_mount;
+
+ /* Allocate read_page block */
+ msblk->read_page = squashfs_cache_init("data",
+ squashfs_max_decompressors(), msblk->block_size);
+ if (msblk->read_page == NULL) {
+ ERROR("Failed to allocate read_page block\n");
+ goto failed_mount;
+ }
+
+ msblk->stream = squashfs_decompressor_setup(sb, flags);
+ if (IS_ERR(msblk->stream)) {
+ err = PTR_ERR(msblk->stream);
+ msblk->stream = NULL;
+ goto failed_mount;
+ }
+
+ next_table = msblk->bytes_used;
+
+ /* Allocate and read id index table */
+ msblk->id_table = squashfs_read_id_index_table(sb,
+ le64_to_cpu(sblk->id_table_start), next_table,
+ le16_to_cpu(sblk->no_ids));
+ if (IS_ERR(msblk->id_table)) {
+ ERROR("unable to read id index table\n");
+ err = PTR_ERR(msblk->id_table);
+ msblk->id_table = NULL;
+ goto failed_mount;
+ }
+ next_table = le64_to_cpu(msblk->id_table[0]);
+
+ /* Handle inode lookup table */
+ lookup_table_start = le64_to_cpu(sblk->lookup_table_start);
+ if (lookup_table_start == SQUASHFS_INVALID_BLK)
+ goto handle_fragments;
+
+handle_fragments:
+ fragments = le32_to_cpu(sblk->fragments);
+ if (fragments == 0)
+ goto check_directory_table;
+ msblk->fragment_cache = squashfs_cache_init("fragment",
+ SQUASHFS_CACHED_FRAGMENTS, msblk->block_size);
+ if (msblk->fragment_cache == NULL) {
+ err = -ENOMEM;
+ goto failed_mount;
+ }
+
+ /* Allocate and read fragment index table */
+ msblk->fragment_index = squashfs_read_fragment_index_table(sb,
+ le64_to_cpu(sblk->fragment_table_start), next_table, fragments);
+ if (IS_ERR(msblk->fragment_index)) {
+ ERROR("unable to read fragment index table\n");
+ err = PTR_ERR(msblk->fragment_index);
+ msblk->fragment_index = NULL;
+ goto failed_mount;
+ }
+ next_table = le64_to_cpu(msblk->fragment_index[0]);
+
+check_directory_table:
+ /* Sanity check directory_table */
+ if (msblk->directory_table > next_table) {
+ err = -EINVAL;
+ goto failed_mount;
+ }
+
+ /* Sanity check inode_table */
+ if (msblk->inode_table >= msblk->directory_table) {
+ err = -EINVAL;
+ goto failed_mount;
+ }
+
+ /* allocate root */
+ root = squashfs_iget(sb, root_inode, 1);
+ if (!root) {
+ err = -ENOMEM;
+ goto failed_mount;
+ }
+
+ sb->s_root = d_make_root(root);
+ if (sb->s_root == NULL) {
+ ERROR("Root inode create failed\n");
+ err = -ENOMEM;
+ goto failed_mount;
+ }
+
+ kfree(sblk);
+
+ return 0;
+
+failed_mount:
+ squashfs_cache_delete(msblk->block_cache);
+ squashfs_cache_delete(msblk->fragment_cache);
+ squashfs_cache_delete(msblk->read_page);
+ squashfs_decompressor_destroy(msblk);
+ kfree(msblk->inode_lookup_table);
+ kfree(msblk->fragment_index);
+ kfree(msblk->id_table);
+ kfree(msblk->xattr_id_table);
+ kfree(sb->s_fs_info);
+ sb->s_fs_info = NULL;
+ kfree(sblk);
+ return err;
+}
+
+
+struct super_block *squashfs_mount(struct fs_device_d *fsdev, int silent)
+{
+ struct super_block *sb;
+
+ dev_info(&fsdev->dev, "squashfs_mount\n");
+
+ sb = xzalloc(sizeof(*sb));
+
+ if (squashfs_fill_super(sb, fsdev, silent)) {
+ kfree(sb);
+ return NULL;
+ }
+
+ return sb;
+}
diff --git a/fs/squashfs/xz_wrapper.c b/fs/squashfs/xz_wrapper.c
new file mode 100644
index 0000000..2659c45
--- /dev/null
+++ b/fs/squashfs/xz_wrapper.c
@@ -0,0 +1,190 @@
+/*
+ * Squashfs - a compressed read only filesystem for Linux
+ *
+ * Copyright (c) 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010
+ * Phillip Lougher <phillip at squashfs.org.uk>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2,
+ * or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * xz_wrapper.c
+ */
+
+
+#include <linux/xz.h>
+#include <linux/bitops.h>
+
+#include "squashfs_fs.h"
+#include "squashfs_fs_sb.h"
+#include "squashfs.h"
+#include "decompressor.h"
+#include "page_actor.h"
+
+struct squashfs_xz {
+ struct xz_dec *state;
+ struct xz_buf buf;
+};
+
+struct disk_comp_opts {
+ __le32 dictionary_size;
+ __le32 flags;
+};
+
+struct comp_opts {
+ int dict_size;
+};
+
+static void *squashfs_xz_comp_opts(struct squashfs_sb_info *msblk,
+ void *buff, int len)
+{
+ struct disk_comp_opts *comp_opts = buff;
+ struct comp_opts *opts;
+ int err = 0, n;
+
+ opts = kmalloc(sizeof(*opts), GFP_KERNEL);
+ if (opts == NULL) {
+ err = -ENOMEM;
+ goto out2;
+ }
+
+ if (comp_opts) {
+ /* check compressor options are the expected length */
+ if (len < sizeof(*comp_opts)) {
+ err = -EIO;
+ goto out;
+ }
+
+ opts->dict_size = le32_to_cpu(comp_opts->dictionary_size);
+
+ /* the dictionary size should be 2^n or 2^n+2^(n+1) */
+ n = ffs(opts->dict_size) - 1;
+ if (opts->dict_size != (1 << n) && opts->dict_size != (1 << n) +
+ (1 << (n + 1))) {
+ err = -EIO;
+ goto out;
+ }
+ } else
+ /* use defaults */
+ opts->dict_size = max_t(int, msblk->block_size,
+ SQUASHFS_METADATA_SIZE);
+
+ return opts;
+
+out:
+ kfree(opts);
+out2:
+ return ERR_PTR(err);
+}
+
+
+static void *squashfs_xz_init(struct squashfs_sb_info *msblk, void *buff)
+{
+ struct comp_opts *comp_opts = buff;
+ struct squashfs_xz *stream;
+ int err;
+
+ stream = kmalloc(sizeof(*stream), GFP_KERNEL);
+ if (stream == NULL) {
+ err = -ENOMEM;
+ goto failed;
+ }
+
+ stream->state = xz_dec_init(XZ_PREALLOC, comp_opts->dict_size);
+ if (stream->state == NULL) {
+ kfree(stream);
+ err = -ENOMEM;
+ goto failed;
+ }
+
+#if XZ_INTERNAL_CRC32
+ xz_crc32_init();
+#endif
+
+ return stream;
+
+failed:
+ ERROR("Failed to initialise xz decompressor\n");
+ return ERR_PTR(err);
+}
+
+
+static void squashfs_xz_free(void *strm)
+{
+ struct squashfs_xz *stream = strm;
+
+ if (stream) {
+ xz_dec_end(stream->state);
+ kfree(stream);
+ }
+}
+
+
+static int squashfs_xz_uncompress(struct squashfs_sb_info *msblk, void *strm,
+ char **bh, int b, int offset, int length,
+ struct squashfs_page_actor *output)
+{
+ enum xz_ret xz_err;
+ int avail, total = 0, k = 0;
+ struct squashfs_xz *stream = strm;
+
+ xz_dec_reset(stream->state);
+ stream->buf.in_pos = 0;
+ stream->buf.in_size = 0;
+ stream->buf.out_pos = 0;
+ stream->buf.out_size = PAGE_CACHE_SIZE;
+ stream->buf.out = squashfs_first_page(output);
+
+ do {
+ if (stream->buf.in_pos == stream->buf.in_size && k < b) {
+ avail = min(length, msblk->devblksize - offset);
+ length -= avail;
+ stream->buf.in = bh[k] + offset;
+ stream->buf.in_size = avail;
+ stream->buf.in_pos = 0;
+ offset = 0;
+ }
+
+ if (stream->buf.out_pos == stream->buf.out_size) {
+ stream->buf.out = squashfs_next_page(output);
+ if (stream->buf.out != NULL) {
+ stream->buf.out_pos = 0;
+ total += PAGE_CACHE_SIZE;
+ }
+ }
+
+ xz_err = xz_dec_run(stream->state, &stream->buf);
+
+ if (stream->buf.in_pos == stream->buf.in_size && k < b)
+ kfree(bh[k++]);
+ } while (xz_err == XZ_OK);
+
+ squashfs_finish_page(output);
+
+ if (xz_err != XZ_STREAM_END || k < b)
+ goto out;
+
+ return total + stream->buf.out_pos;
+
+out:
+ for (; k < b; k++)
+ kfree(bh[k]);
+
+ return -EIO;
+}
+
+const struct squashfs_decompressor squashfs_xz_comp_ops = {
+ .init = squashfs_xz_init,
+ .comp_opts = squashfs_xz_comp_opts,
+ .free = squashfs_xz_free,
+ .decompress = squashfs_xz_uncompress,
+ .id = XZ_COMPRESSION,
+ .name = "xz",
+ .supported = 1
+};
--
2.1.4
More information about the barebox
mailing list