Add the glue code, and also update the documentation.
Signed-off-by: Phillip Lougher <phil...@squashfs.org.uk>
---
Documentation/filesystems/squashfs.txt | 8 ++++----
fs/squashfs/Kconfig | 15 +++++++++++++++
fs/squashfs/Makefile | 1 +
fs/squashfs/decompressor.c | 7 +++++++
fs/squashfs/decompressor.h | 4 ++++
5 files changed, 31 insertions(+), 4 deletions(-)
diff --git a/Documentation/filesystems/squashfs.txt
b/Documentation/filesystems/squashfs.txt
index 403c090..e5274f8 100644
--- a/Documentation/filesystems/squashfs.txt
+++ b/Documentation/filesystems/squashfs.txt
@@ -2,10 +2,10 @@ SQUASHFS 4.0 FILESYSTEM
=======================
Squashfs is a compressed read-only filesystem for Linux.
-It uses zlib/lzo/xz compression to compress 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 1Mbytes (default block size 128K).
+It uses zlib, lz4, lzo, or xz compression to compress 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 1Mbytes (default block size 128K).
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 constrained
diff --git a/fs/squashfs/Kconfig b/fs/squashfs/Kconfig
index b6fa865..ffb093e 100644
--- a/fs/squashfs/Kconfig
+++ b/fs/squashfs/Kconfig
@@ -120,6 +120,21 @@ config SQUASHFS_ZLIB
If unsure, say Y.
+config SQUASHFS_LZ4
+ bool "Include support for LZ4 compressed file systems"
+ depends on SQUASHFS
+ select LZ4_DECOMPRESS
+ help
+ Saying Y here includes support for reading Squashfs file systems
+ compressed with LZ4 compression. LZ4 compression is mainly
+ aimed at embedded systems with slower CPUs where the overheads
+ of zlib are too high.
+
+ LZ4 is not the standard compression used in Squashfs and so most
+ file systems will be readable without selecting this option.
+
+ If unsure, say N.
+
config SQUASHFS_LZO
bool "Include support for LZO compressed file systems"
depends on SQUASHFS
diff --git a/fs/squashfs/Makefile b/fs/squashfs/Makefile
index 4132520..246a6f3 100644
--- a/fs/squashfs/Makefile
+++ b/fs/squashfs/Makefile
@@ -11,6 +11,7 @@ squashfs-$(CONFIG_SQUASHFS_DECOMP_SINGLE) +=
decompressor_single.o
squashfs-$(CONFIG_SQUASHFS_DECOMP_MULTI) += decompressor_multi.o
squashfs-$(CONFIG_SQUASHFS_DECOMP_MULTI_PERCPU) += decompressor_multi_percpu.o
squashfs-$(CONFIG_SQUASHFS_XATTR) += xattr.o xattr_id.o
+squashfs-$(CONFIG_SQUASHFS_LZ4) += lz4_wrapper.o
squashfs-$(CONFIG_SQUASHFS_LZO) += lzo_wrapper.o
squashfs-$(CONFIG_SQUASHFS_XZ) += xz_wrapper.o
squashfs-$(CONFIG_SQUASHFS_ZLIB) += zlib_wrapper.o
diff --git a/fs/squashfs/decompressor.c b/fs/squashfs/decompressor.c
index ac22fe7..505d6aa 100644
--- a/fs/squashfs/decompressor.c
+++ b/fs/squashfs/decompressor.c
@@ -41,6 +41,12 @@ 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, 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
@@ -65,6 +71,7 @@ static const struct squashfs_decompressor
squashfs_unknown_comp_ops = {
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,
diff --git a/fs/squashfs/decompressor.h b/fs/squashfs/decompressor.h
index af09853..a25713c 100644
--- a/fs/squashfs/decompressor.h
+++ b/fs/squashfs/decompressor.h
@@ -46,6 +46,10 @@ static inline void *squashfs_comp_opts(struct
squashfs_sb_info *msblk,
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
--
1.7.10.4
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