[PATCH 0/17] Kernel compression: add ZSTD, remove LZMA1 and BZIP2

[PATCH 0/17] Kernel compression: add ZSTD, remove LZMA1 and BZIP2

[Adam Borowski]

Hi!
As new compressors get invented, they tend to find their way into the
kernel, yet we never prune superseded ones.  It's time to do so.

In particular, BZIP2 is drastically slower than other compressors we
have, even when they achieve smaller sizes.  It takes more memory, too.
And, BZIP2 is not used anywhere else in the kernel -- just for booting
the kernel itself and the initrd.  Thus, we can drop it from the tree
completely, making Linus happier by around 900 lines.

LZMA1 is redundant with XZ (LZMA2), and unlike the latter, it uses its own
copy of code that's not shared with anything else (some drivers use XZ).
Let's drop it as well.  Some bootloaders can use it thus let's keep the
Kconfig option, but I left no piece of code inside the kernel itself.

On the other hand, Nick Terrell has a couple of patches adding ZSTD support
(using code already in use in multiple pieces around the kernel).  ZSTD is
strong and fast, obsoleting all mid-range compressors.  As the removal of
BZIP2 and LZMA1 would be hopelessly entangled with this addition, I'm
resending Nick's patches here.  I've been booting using them since Oct'17
on amd64 (kernel+initrd), armhf and arm64 (initrd) without issues, other
folks tested various other architectures as well.

Thus, I'd recommend people to use:
* XZ for most machines
* ZSTD where speed is important
* maaaaybe LZ4 is some special cases
(grub and u-boot are ridiculously slow at reading, making fast but weak
decompressors a net loss.  On the other hand, XZ decompresses pretty fast
but is very slow at compress time, making ZSTD preferred for rapid devel
cycles.)

* we can't get rid of GZIP in foreseable future
* LZO is obsolete but is used elsewhere in the kernel

Total:
 69 files changed, 518 insertions(+), 1785 deletions(-)

Not sure whose tree this patchset should go through.  I'm also not sure
how finely split into commits you want the arch bits be; I included
defconfig bits all together, yet separated code changes per-arch.


Meow!
-- 
⢀⣴⠾⠻⢶⣦⠀ 
⣾⠁⢠⠒⠀⣿⡁ A dumb species has no way to open a tuna can.
⢿⡄⠘⠷⠚⠋⠀ A smart species invents a can opener.
⠈⠳⣄⠀⠀⠀⠀ A master species delegates.

[PATCH 01/17] lib: Add support for ZSTD-compressed kernel

[Adam Borowski]

From: Nick Terrell <terrelln@fb.com>

Add support for extracting ZSTD-compressed kernel images, as well as
ZSTD-compressed ramdisk images in the kernel boot process.

When neither `fill' nor `flush' are used, the decompression function
requires a constant amount of memory (192 KB is sufficient). When either
is used the decompression function requires memory proportional to the
window size used during compression, which is limited to 8 MB. The maximum
memory usage is just over 8 MB.

Fix up lib/zstd and lib/xxhash.c for the preboot environment. They avoid
declaring themselves as modules. A memcpy() call needs to be a
__builtin_memcpy() for performance. The gcc-7.1 bug in ZSTD_wildcopy() was
fixed in gcc-7.2, so it can be gated, since it hurts performance.

Signed-off-by: Nick Terrell <terrelln@fb.com>
---
 include/linux/decompress/unzstd.h |  26 +++
 init/Kconfig                      |  14 +-
 lib/Kconfig                       |   4 +
 lib/Makefile                      |   1 +
 lib/decompress.c                  |   5 +
 lib/decompress_unzstd.c           | 341 ++++++++++++++++++++++++++++++
 lib/xxhash.c                      |  21 +-
 lib/zstd/decompress.c             |   2 +
 lib/zstd/fse_decompress.c         |   9 +-
 lib/zstd/zstd_internal.h          |  10 +-
 scripts/Makefile.lib              |  15 ++
 usr/Kconfig                       |  22 ++
 12 files changed, 451 insertions(+), 19 deletions(-)
 create mode 100644 include/linux/decompress/unzstd.h
 create mode 100644 lib/decompress_unzstd.c

diff --git a/include/linux/decompress/unzstd.h b/include/linux/decompress/unzstd.h
new file mode 100644
index 000000000000..6f3022cd0955
--- /dev/null
+++ b/include/linux/decompress/unzstd.h
@@ -0,0 +1,26 @@
+/*
+ * Copyright (C) 2017 Facebook
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public
+ * License v2 as published by the Free Software Foundation.
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+#ifndef LINUX_DECOMPRESS_UNZSTD_H
+#define LINUX_DECOMPRESS_UNZSTD_H
+
+int unzstd(unsigned char *inbuf, long len,
+	   long (*fill)(void*, unsigned long),
+	   long (*flush)(void*, unsigned long),
+	   unsigned char *output,
+	   long *pos,
+	   void (*error_fn)(char *x));
+#endif
diff --git a/init/Kconfig b/init/Kconfig
index a4112e95724a..ffa5ae4abc88 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -134,13 +134,16 @@ config HAVE_KERNEL_LZO
 config HAVE_KERNEL_LZ4
 	bool
 
+config HAVE_KERNEL_ZSTD
+	bool
+
 config HAVE_KERNEL_UNCOMPRESSED
 	bool
 
 choice
 	prompt "Kernel compression mode"
 	default KERNEL_GZIP
-	depends on HAVE_KERNEL_GZIP || HAVE_KERNEL_BZIP2 || HAVE_KERNEL_LZMA || HAVE_KERNEL_XZ || HAVE_KERNEL_LZO || HAVE_KERNEL_LZ4 || HAVE_KERNEL_UNCOMPRESSED
+	depends on HAVE_KERNEL_GZIP || HAVE_KERNEL_BZIP2 || HAVE_KERNEL_LZMA || HAVE_KERNEL_XZ || HAVE_KERNEL_LZO || HAVE_KERNEL_LZ4 || HAVE_KERNEL_ZSTD || HAVE_KERNEL_UNCOMPRESSED
 	help
 	  The linux kernel is a kind of self-extracting executable.
 	  Several compression algorithms are available, which differ
@@ -219,6 +222,15 @@ config KERNEL_LZ4
 	  is about 8% bigger than LZO. But the decompression speed is
 	  faster than LZO.
 
+config KERNEL_ZSTD
+	bool "ZSTD"
+	depends on HAVE_KERNEL_ZSTD
+	help
+	  ZSTD is a compression algorithm targeting intermediate compression
+	  with fast decompression speed. It will compress better than GZIP and
+	  decompress around the same speed as LZO, but slower than LZ4. You
+	  will need at least 192 KB RAM or more for booting.
+
 config KERNEL_UNCOMPRESSED
 	bool "None"
 	depends on HAVE_KERNEL_UNCOMPRESSED
diff --git a/lib/Kconfig b/lib/Kconfig
index a9965f4af4dd..e7ab43fd5461 100644
--- a/lib/Kconfig
+++ b/lib/Kconfig
@@ -304,6 +304,10 @@ config DECOMPRESS_LZ4
 	select LZ4_DECOMPRESS
 	tristate
 
+config DECOMPRESS_ZSTD
+	select ZSTD_DECOMPRESS
+	tristate
+
 #
 # Generic allocator support is selected if needed
 #
diff --git a/lib/Makefile b/lib/Makefile
index db06d1237898..58b48993f48a 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -139,6 +139,7 @@ lib-$(CONFIG_DECOMPRESS_LZMA) += decompress_unlzma.o
 lib-$(CONFIG_DECOMPRESS_XZ) += decompress_unxz.o
 lib-$(CONFIG_DECOMPRESS_LZO) += decompress_unlzo.o
 lib-$(CONFIG_DECOMPRESS_LZ4) += decompress_unlz4.o
+lib-$(CONFIG_DECOMPRESS_ZSTD) += decompress_unzstd.o
 
 obj-$(CONFIG_TEXTSEARCH) += textsearch.o
 obj-$(CONFIG_TEXTSEARCH_KMP) += ts_kmp.o
diff --git a/lib/decompress.c b/lib/decompress.c
index 857ab1af1ef3..ab3fc90ffc64 100644
--- a/lib/decompress.c
+++ b/lib/decompress.c
@@ -13,6 +13,7 @@
 #include <linux/decompress/inflate.h>
 #include <linux/decompress/unlzo.h>
 #include <linux/decompress/unlz4.h>
+#include <linux/decompress/unzstd.h>
 
 #include <linux/types.h>
 #include <linux/string.h>
@@ -37,6 +38,9 @@
 #ifndef CONFIG_DECOMPRESS_LZ4
 # define unlz4 NULL
 #endif
+#ifndef CONFIG_DECOMPRESS_ZSTD
+# define unzstd NULL
+#endif
 
 struct compress_format {
 	unsigned char magic[2];
@@ -52,6 +56,7 @@ static const struct compress_format compressed_formats[] __initconst = {
 	{ {0xfd, 0x37}, "xz", unxz },
 	{ {0x89, 0x4c}, "lzo", unlzo },
 	{ {0x02, 0x21}, "lz4", unlz4 },
+	{ {0x28, 0xb5}, "zstd", unzstd },
 	{ {0, 0}, NULL, NULL }
 };
 
diff --git a/lib/decompress_unzstd.c b/lib/decompress_unzstd.c
new file mode 100644
index 000000000000..84315dc9bf24
--- /dev/null
+++ b/lib/decompress_unzstd.c
@@ -0,0 +1,341 @@
+/*
+ * Copyright (C) 2017 Facebook
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public
+ * License v2 as published by the Free Software Foundation.
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+/*
+ * Important notes about in-place decompression
+ *
+ * At least on x86, the kernel is decompressed in place: the compressed data
+ * is placed to the end of the output buffer, and the decompressor overwrites
+ * most of the compressed data. There must be enough safety margin to
+ * guarantee that the write position is always behind the read position.
+ *
+ * The safety margin for ZSTD with a 128 KB block size is calculated below.
+ * Note that the margin with ZSTD is bigger than with GZIP or XZ!
+ *
+ * The worst case for in-place decompression is that the beginning of
+ * the file is compressed extremely well, and the rest of the file is
+ * uncompressible. Thus, we must look for worst-case expansion when the
+ * compressor is encoding uncompressible data.
+ *
+ * The structure of the .zst file in case of a compresed kernel is as follows.
+ * Maximum sizes (as bytes) of the fields are in parenthesis.
+ *
+ *    Frame Header: (18)
+ *    Blocks: (N)
+ *    Checksum: (4)
+ *
+ * The frame header and checksum overhead is at most 22 bytes.
+ *
+ * ZSTD stores the data in blocks. Each block has a header whose size is
+ * a 3 bytes. After the block header, there is up to 128 KB of payload.
+ * The maximum uncompressed size of the payload is 128 KB. The minimum
+ * uncompressed size of the payload is never less than the payload size
+ * (excluding the block header).
+ *
+ * The assumption, that the uncompressed size of the payload is never
+ * smaller than the payload itself, is valid only when talking about
+ * the payload as a whole. It is possible that the payload has parts where
+ * the decompressor consumes more input than it produces output. Calculating
+ * the worst case for this would be tricky. Instead of trying to do that,
+ * let's simply make sure that the decompressor never overwrites any bytes
+ * of the payload which it is currently reading.
+ *
+ * Now we have enough information to calculate the safety margin. We need
+ *   - 22 bytes for the .zst file format headers;
+ *   - 3 bytes per every 128 KiB of uncompressed size (one block header per
+ *     block); and
+ *   - 128 KiB (biggest possible zstd block size) to make sure that the
+ *     decompressor never overwrites anything from the block it is currently
+ *     reading.
+ *
+ * We get the following formula:
+ *
+ *    safety_margin = 22 + uncompressed_size * 3 / 131072 + 131072
+ *                 <= 22 + (uncompressed_size >> 15) + 131072
+ */
+
+#ifdef STATIC
+	/* Preboot environments #include "path/to/decompress_unzstd.c".
+	 * All of the source files we depend on must be #included.
+	 * zstd's only source dependeny is xxhash, which has no source
+	 * dependencies.
+	 *
+	 * zstd and xxhash both avoid declaring themselves as modules
+	 * when PREBOOT is defined.
+	 */
+#	define PREBOOT
+#	include "xxhash.c"
+#	include "zstd/entropy_common.c"
+#	include "zstd/fse_decompress.c"
+#	include "zstd/huf_decompress.c"
+#	include "zstd/zstd_common.c"
+#	include "zstd/decompress.c"
+#endif
+
+#include <linux/decompress/mm.h>
+#include <linux/kernel.h>
+#include <linux/zstd.h>
+
+/* 8 MB maximum window size */
+#define ZSTD_WINDOWSIZE_MAX	(1 << 23)
+/* Size of the input and output buffers in multi-call mdoe */
+#define ZSTD_IOBUF_SIZE		4096
+
+static int INIT handle_zstd_error(size_t ret, void (*error)(char *x))
+{
+	const int err = ZSTD_getErrorCode(ret);
+
+	if (!ZSTD_isError(ret))
+		return 0;
+
+	switch (err) {
+	case ZSTD_error_memory_allocation:
+		error("ZSTD decompressor ran out of memory");
+		break;
+	case ZSTD_error_prefix_unknown:
+		error("Input is not in the ZSTD format (wrong magic bytes)");
+		break;
+	case ZSTD_error_dstSize_tooSmall:
+	case ZSTD_error_corruption_detected:
+	case ZSTD_error_checksum_wrong:
+		error("ZSTD-compressed data is corrupt");
+		break;
+	default:
+		error("ZSTD-compressed data is probably corrupt");
+		break;
+	}
+	return -1;
+}
+
+/* Handle the case where we have the entire input and output in one segment.
+ * We can allocate less memory (no circular buffer for the sliding window),
+ * and avoid some memcpy() calls.
+ */
+static int INIT decompress_single(const u8 *in_buf, long in_len, u8 *out_buf,
+				  long out_len, long *in_pos,
+				  void (*error)(char *x))
+{
+	const size_t wksp_size = ZSTD_DCtxWorkspaceBound();
+	void *wksp = large_malloc(wksp_size);
+	ZSTD_DCtx *dctx = ZSTD_initDCtx(wksp, wksp_size);
+	int err;
+	size_t ret;
+
+	if (dctx == NULL) {
+		error("Out of memory while allocating ZSTD_DCtx");
+		err = -1;
+		goto out;
+	}
+	/* Find out how large the frame actually is, there may be junk at
+	 * the end of the frame that ZSTD_decompressDCtx() can't handle.
+	 */
+	ret = ZSTD_findFrameCompressedSize(in_buf, in_len);
+	err = handle_zstd_error(ret, error);
+	if (err)
+		goto out;
+	in_len = (long)ret;
+
+	ret = ZSTD_decompressDCtx(dctx, out_buf, out_len, in_buf, in_len);
+	err = handle_zstd_error(ret, error);
+	if (err)
+		goto out;
+
+	if (in_pos != NULL)
+		*in_pos = in_len;
+
+	err = 0;
+out:
+	if (wksp != NULL)
+		large_free(wksp);
+	return err;
+}
+
+static int INIT __unzstd(unsigned char *in_buf, long in_len,
+			 long (*fill)(void*, unsigned long),
+			 long (*flush)(void*, unsigned long),
+			 unsigned char *out_buf, long out_len,
+			 long *in_pos,
+			 void (*error)(char *x))
+{
+	ZSTD_inBuffer in;
+	ZSTD_outBuffer out;
+	ZSTD_frameParams params;
+	void *in_allocated = NULL;
+	void *out_allocated = NULL;
+	void *wksp = NULL;
+	size_t wksp_size;
+	ZSTD_DStream *dstream;
+	int err;
+	size_t ret;
+
+	if (out_len == 0)
+		out_len = LONG_MAX; /* no limit */
+
+	if (fill == NULL && flush == NULL)
+		/* We can decompress faster and with less memory when we have a
+		 * single chunk.
+		 */
+		return decompress_single(in_buf, in_len, out_buf, out_len,
+					 in_pos, error);
+
+	/* If in_buf is not provided, we must be using fill(), so allocate
+	 * a large enough buffer. If it is provided, it must be at least
+	 * ZSTD_IOBUF_SIZE large.
+	 */
+	if (in_buf == NULL) {
+		in_allocated = malloc(ZSTD_IOBUF_SIZE);
+		if (in_allocated == NULL) {
+			error("Out of memory while allocating input buffer");
+			err = -1;
+			goto out;
+		}
+		in_buf = in_allocated;
+		in_len = 0;
+	}
+	/* Read the first chunk, since we need to decode the frame header */
+	if (fill != NULL)
+		in_len = fill(in_buf, ZSTD_IOBUF_SIZE);
+	if (in_len < 0) {
+		error("ZSTD-compressed data is truncated");
+		err = -1;
+		goto out;
+	}
+	/* Set the first non-empty input buffer */
+	in.src = in_buf;
+	in.pos = 0;
+	in.size = in_len;
+	/* Allocate the output buffer if we are using flush(). */
+	if (flush != NULL) {
+		out_allocated = malloc(ZSTD_IOBUF_SIZE);
+		if (out_allocated == NULL) {
+			error("Out of memory while allocating output buffer");
+			err = -1;
+			goto out;
+		}
+		out_buf = out_allocated;
+		out_len = ZSTD_IOBUF_SIZE;
+	}
+	/* Set the output buffer */
+	out.dst = out_buf;
+	out.pos = 0;
+	out.size = out_len;
+
+	/* We need to know the window size to allocate the ZSTD_DStream.
+	 * Since we are streaming, we need to allocate a buffer for the sliding
+	 * window. The window size varies from 1 KB to ZSTD_WINDOWSIZE_MAX
+	 * (8 MB), so it is important to use the actual value so as not to
+	 * waste memory when it is smaller.
+	 */
+	ret = ZSTD_getFrameParams(&params, in.src, in.size);
+	err = handle_zstd_error(ret, error);
+	if (err)
+		goto out;
+	if (ret != 0) {
+		error("ZSTD-compressed data has an incomplete frame header");
+		err = -1;
+		goto out;
+	}
+	if (params.windowSize > ZSTD_WINDOWSIZE_MAX) {
+		error("ZSTD-compressed data has too large a window size");
+		err = -1;
+		goto out;
+	}
+
+	/* Allocate the ZSTD_DStream now that we know how much memory is
+	 * required.
+	 */
+	wksp_size = ZSTD_DStreamWorkspaceBound(params.windowSize);
+	wksp = large_malloc(wksp_size);
+	dstream = ZSTD_initDStream(params.windowSize, wksp, wksp_size);
+	if (dstream == NULL) {
+		error("Out of memory while allocating ZSTD_DStream");
+		err = -1;
+		goto out;
+	}
+	/* Decompression loop:
+	 * Read more data if necessary (error if no more data can be read).
+	 * Call the decompression function, which returns 0 when finished.
+	 * Flush any data produced if using flush().
+	 */
+	if (in_pos != NULL)
+		*in_pos = 0;
+	do {
+		/* If we need to reload data, either we have fill() and can
+		 * try to get more data, or we don't and the input is truncated.
+		 */
+		if (in.pos == in.size) {
+			if (in_pos != NULL)
+				*in_pos += in.pos;
+			in_len = fill ? fill(in_buf, ZSTD_IOBUF_SIZE) : -1;
+			if (in_len < 0) {
+				error("ZSTD-compressed data is truncated");
+				err = -1;
+				goto out;
+			}
+			in.pos = 0;
+			in.size = in_len;
+		}
+		/* Returns zero when the frame is complete */
+		ret = ZSTD_decompressStream(dstream, &out, &in);
+		err = handle_zstd_error(ret, error);
+		if (err)
+			goto out;
+		/* Flush all of the data produced if using flush() */
+		if (flush != NULL && out.pos > 0) {
+			if (out.pos != flush(out.dst, out.pos)) {
+				error("Failed to flush()");
+				err = -1;
+				goto out;
+			}
+			out.pos = 0;
+		}
+	} while (ret != 0);
+
+	if (in_pos != NULL)
+		*in_pos += in.pos;
+
+	err = 0;
+out:
+	if (in_allocated != NULL)
+		free(in_allocated);
+	if (out_allocated != NULL)
+		free(out_allocated);
+	if (wksp != NULL)
+		large_free(wksp);
+	return err;
+}
+
+#ifndef PREBOOT
+STATIC int INIT unzstd(unsigned char *buf, long len,
+		       long (*fill)(void*, unsigned long),
+		       long (*flush)(void*, unsigned long),
+		       unsigned char *out_buf,
+		       long *pos,
+		       void (*error)(char *x))
+{
+	return __unzstd(buf, len, fill, flush, out_buf, 0, pos, error);
+}
+#else
+STATIC int INIT __decompress(unsigned char *buf, long len,
+			     long (*fill)(void*, unsigned long),
+			     long (*flush)(void*, unsigned long),
+			     unsigned char *out_buf, long out_len,
+			     long *pos,
+			     void (*error)(char *x))
+{
+	return __unzstd(buf, len, fill, flush, out_buf, out_len, pos, error);
+}
+#endif
diff --git a/lib/xxhash.c b/lib/xxhash.c
index aa61e2a3802f..7f1d3cb01729 100644
--- a/lib/xxhash.c
+++ b/lib/xxhash.c
@@ -80,13 +80,11 @@ void xxh32_copy_state(struct xxh32_state *dst, const struct xxh32_state *src)
 {
 	memcpy(dst, src, sizeof(*dst));
 }
-EXPORT_SYMBOL(xxh32_copy_state);
 
 void xxh64_copy_state(struct xxh64_state *dst, const struct xxh64_state *src)
 {
 	memcpy(dst, src, sizeof(*dst));
 }
-EXPORT_SYMBOL(xxh64_copy_state);
 
 /*-***************************
  * Simple Hash Functions
@@ -151,7 +149,6 @@ uint32_t xxh32(const void *input, const size_t len, const uint32_t seed)
 
 	return h32;
 }
-EXPORT_SYMBOL(xxh32);
 
 static uint64_t xxh64_round(uint64_t acc, const uint64_t input)
 {
@@ -234,7 +231,6 @@ uint64_t xxh64(const void *input, const size_t len, const uint64_t seed)
 
 	return h64;
 }
-EXPORT_SYMBOL(xxh64);
 
 /*-**************************************************
  * Advanced Hash Functions
@@ -251,7 +247,6 @@ void xxh32_reset(struct xxh32_state *statePtr, const uint32_t seed)
 	state.v4 = seed - PRIME32_1;
 	memcpy(statePtr, &state, sizeof(state));
 }
-EXPORT_SYMBOL(xxh32_reset);
 
 void xxh64_reset(struct xxh64_state *statePtr, const uint64_t seed)
 {
@@ -265,7 +260,6 @@ void xxh64_reset(struct xxh64_state *statePtr, const uint64_t seed)
 	state.v4 = seed - PRIME64_1;
 	memcpy(statePtr, &state, sizeof(state));
 }
-EXPORT_SYMBOL(xxh64_reset);
 
 int xxh32_update(struct xxh32_state *state, const void *input, const size_t len)
 {
@@ -334,7 +328,6 @@ int xxh32_update(struct xxh32_state *state, const void *input, const size_t len)
 
 	return 0;
 }
-EXPORT_SYMBOL(xxh32_update);
 
 uint32_t xxh32_digest(const struct xxh32_state *state)
 {
@@ -372,7 +365,6 @@ uint32_t xxh32_digest(const struct xxh32_state *state)
 
 	return h32;
 }
-EXPORT_SYMBOL(xxh32_digest);
 
 int xxh64_update(struct xxh64_state *state, const void *input, const size_t len)
 {
@@ -439,7 +431,6 @@ int xxh64_update(struct xxh64_state *state, const void *input, const size_t len)
 
 	return 0;
 }
-EXPORT_SYMBOL(xxh64_update);
 
 uint64_t xxh64_digest(const struct xxh64_state *state)
 {
@@ -494,7 +485,19 @@ uint64_t xxh64_digest(const struct xxh64_state *state)
 
 	return h64;
 }
+
+#ifndef PREBOOT
+EXPORT_SYMBOL(xxh32_copy_state);
+EXPORT_SYMBOL(xxh64_copy_state);
+EXPORT_SYMBOL(xxh32);
+EXPORT_SYMBOL(xxh64);
+EXPORT_SYMBOL(xxh32_reset);
+EXPORT_SYMBOL(xxh64_reset);
+EXPORT_SYMBOL(xxh32_update);
+EXPORT_SYMBOL(xxh32_digest);
+EXPORT_SYMBOL(xxh64_update);
 EXPORT_SYMBOL(xxh64_digest);
 
 MODULE_LICENSE("Dual BSD/GPL");
 MODULE_DESCRIPTION("xxHash");
+#endif
diff --git a/lib/zstd/decompress.c b/lib/zstd/decompress.c
index b17846725ca0..b7b6599be69e 100644
--- a/lib/zstd/decompress.c
+++ b/lib/zstd/decompress.c
@@ -2487,6 +2487,7 @@ size_t ZSTD_decompressStream(ZSTD_DStream *zds, ZSTD_outBuffer *output, ZSTD_inB
 	}
 }
 
+#ifndef PREBOOT
 EXPORT_SYMBOL(ZSTD_DCtxWorkspaceBound);
 EXPORT_SYMBOL(ZSTD_initDCtx);
 EXPORT_SYMBOL(ZSTD_decompressDCtx);
@@ -2526,3 +2527,4 @@ EXPORT_SYMBOL(ZSTD_insertBlock);
 
 MODULE_LICENSE("Dual BSD/GPL");
 MODULE_DESCRIPTION("Zstd Decompressor");
+#endif
diff --git a/lib/zstd/fse_decompress.c b/lib/zstd/fse_decompress.c
index a84300e5a013..0b353530fb3f 100644
--- a/lib/zstd/fse_decompress.c
+++ b/lib/zstd/fse_decompress.c
@@ -47,6 +47,7 @@
 ****************************************************************/
 #include "bitstream.h"
 #include "fse.h"
+#include "zstd_internal.h"
 #include <linux/compiler.h>
 #include <linux/kernel.h>
 #include <linux/string.h> /* memcpy, memset */
@@ -60,14 +61,6 @@
 		enum { FSE_static_assert = 1 / (int)(!!(c)) }; \
 	} /* use only *after* variable declarations */
 
-/* check and forward error code */
-#define CHECK_F(f)                  \
-	{                           \
-		size_t const e = f; \
-		if (FSE_isError(e)) \
-			return e;   \
-	}
-
 /* **************************************************************
 *  Templates
 ****************************************************************/
diff --git a/lib/zstd/zstd_internal.h b/lib/zstd/zstd_internal.h
index 1a79fab9e13a..40026c0da892 100644
--- a/lib/zstd/zstd_internal.h
+++ b/lib/zstd/zstd_internal.h
@@ -127,7 +127,13 @@ static const U32 OF_defaultNormLog = OF_DEFAULTNORMLOG;
 *  Shared functions to include for inlining
 *********************************************/
 ZSTD_STATIC void ZSTD_copy8(void *dst, const void *src) {
-	memcpy(dst, src, 8);
+	/* zstd relies heavily on gcc being able to analyze and inline this
+	 * memcpy() call, since it is called in a tight loop. Preboot mode
+	 * is compiled in freestanding mode, which stops gcc from analyzing
+	 * memcpy(). Use __builtin_memcpy() to tell gcc to analyze this as a
+	 * regular memcpy().
+	 */
+	__builtin_memcpy(dst, src, 8);
 }
 /*! ZSTD_wildcopy() :
 *   custom version of memcpy(), can copy up to 7 bytes too many (8 bytes if length==0) */
@@ -137,6 +143,7 @@ ZSTD_STATIC void ZSTD_wildcopy(void *dst, const void *src, ptrdiff_t length)
 	const BYTE* ip = (const BYTE*)src;
 	BYTE* op = (BYTE*)dst;
 	BYTE* const oend = op + length;
+#if GCC_VERSION >= 70000 && GCC_VERSION < 70200
 	/* Work around https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81388.
 	 * Avoid the bad case where the loop only runs once by handling the
 	 * special case separately. This doesn't trigger the bug because it
@@ -144,6 +151,7 @@ ZSTD_STATIC void ZSTD_wildcopy(void *dst, const void *src, ptrdiff_t length)
 	 */
 	if (length <= 8)
 		return ZSTD_copy8(dst, src);
+#endif
 	do {
 		ZSTD_copy8(op, ip);
 		op += 8;
diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib
index 8fe4468f9bda..e79bb1444b29 100644
--- a/scripts/Makefile.lib
+++ b/scripts/Makefile.lib
@@ -389,6 +389,21 @@ cmd_xzmisc = (cat $(filter-out FORCE,$^) | \
 	xz --check=crc32 --lzma2=dict=1MiB) > $@ || \
 	(rm -f $@ ; false)
 
+# ZSTD
+# ---------------------------------------------------------------------------
+# Appends the uncompressed size of the data using size_append. The .zst
+# format has the size information available at the beginning of the file too,
+# but it's in a more complex format and it's good to avoid changing the part
+# of the boot code that reads the uncompressed size.
+# Note that the bytes added by size_append will make the zstd tool think that
+# the file is corrupt. This is expected.
+
+quiet_cmd_zstd = ZSTD    $@
+cmd_zstd = (cat $(filter-out FORCE,$^) | \
+	zstd -19 && \
+        $(call size_append, $(filter-out FORCE,$^))) > $@ || \
+	(rm -f $@ ; false)
+
 # ASM offsets
 # ---------------------------------------------------------------------------
 
diff --git a/usr/Kconfig b/usr/Kconfig
index 43658b8a975e..5ff529b75ee1 100644
--- a/usr/Kconfig
+++ b/usr/Kconfig
@@ -106,6 +106,15 @@ config RD_LZ4
 	  Support loading of a LZ4 encoded initial ramdisk or cpio buffer
 	  If unsure, say N.
 
+config RD_ZSTD
+	bool "Support initial ramdisk/ramfs compressed using ZSTD"
+	default y
+	depends on BLK_DEV_INITRD
+	select DECOMPRESS_ZSTD
+	help
+	  Support loading of a ZSTD encoded initial ramdisk or cpio buffer.
+	  If unsure, say N.
+
 choice
 	prompt "Built-in initramfs compression mode"
 	depends on INITRAMFS_SOURCE!=""
@@ -214,6 +223,17 @@ config INITRAMFS_COMPRESSION_LZ4
 	  If you choose this, keep in mind that most distros don't provide lz4
 	  by default which could cause a build failure.
 
+config INITRAMFS_COMPRESSION_ZSTD
+	bool "ZSTD"
+	depends on RD_ZSTD
+	help
+	  ZSTD is a compression algorithm targeting intermediate compression
+	  with fast decompression speed. It will compress better than GZIP and
+	  decompress around the same speed as LZO, but slower than LZ4.
+
+	  If you choose this, keep in mind that you may need to install the zstd
+	  tool to be able to compress the initram.
+
 endchoice
 
 config INITRAMFS_COMPRESSION
@@ -226,10 +246,12 @@ config INITRAMFS_COMPRESSION
 	default ".xz"   if INITRAMFS_COMPRESSION_XZ
 	default ".lzo"  if INITRAMFS_COMPRESSION_LZO
 	default ".lz4"  if INITRAMFS_COMPRESSION_LZ4
+	default ".zst"  if INITRAMFS_COMPRESSION_ZSTD
 	default ".gz"   if RD_GZIP
 	default ".lz4"  if RD_LZ4
 	default ".lzo"  if RD_LZO
 	default ".xz"   if RD_XZ
 	default ".lzma" if RD_LZMA
 	default ".bz2"  if RD_BZIP2
+	default ".zst"  if RD_ZSTD
 	default ""
-- 
2.19.1

[PATCH 02/17] x86: Add support for ZSTD-compressed kernel

[Adam Borowski]

From: Nick Terrell <terrelln@fb.com>

Integrates the ZSTD decompression code to the x86 pre-boot code.

Zstandard requires slightly more memory during the kernel decompression
on x86 (192 KB vs 64 KB), and the memory usage is independent of the
window size.

Zstandard requires memory proportional to the window size used during
compression for decompressing the ramdisk image, since streaming mode is
used. Newer versions of zstd (1.3.2+) list the window size of a file
with `zstd -lv <file>'. The absolute maximum amount of memory required
is just over 8 MB.

Signed-off-by: Nick Terrell <terrelln@fb.com>
---
 Documentation/x86/boot.txt        | 6 +++---
 arch/x86/Kconfig                  | 1 +
 arch/x86/boot/compressed/Makefile | 5 ++++-
 arch/x86/boot/compressed/misc.c   | 4 ++++
 arch/x86/boot/header.S            | 8 +++++++-
 arch/x86/include/asm/boot.h       | 6 ++++--
 6 files changed, 23 insertions(+), 7 deletions(-)

diff --git a/Documentation/x86/boot.txt b/Documentation/x86/boot.txt
index 7727db8f94bc..a47b6bae3356 100644
--- a/Documentation/x86/boot.txt
+++ b/Documentation/x86/boot.txt
@@ -685,9 +685,9 @@ Protocol:	2.08+
   uncompressed data should be determined using the standard magic
   numbers.  The currently supported compression formats are gzip
   (magic numbers 1F 8B or 1F 9E), bzip2 (magic number 42 5A), LZMA
-  (magic number 5D 00), XZ (magic number FD 37), and LZ4 (magic number
-  02 21).  The uncompressed payload is currently always ELF (magic
-  number 7F 45 4C 46).
+  (magic number 5D 00), XZ (magic number FD 37), LZ4 (magic number
+  02 21) and ZSTD (magic number 28 B5). The uncompressed payload is
+  currently always ELF (magic number 7F 45 4C 46).
 
 Field name:	payload_length
 Type:		read
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index ba7e3464ee92..203f7467f5c4 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -164,6 +164,7 @@ config X86
 	select HAVE_KERNEL_LZMA
 	select HAVE_KERNEL_LZO
 	select HAVE_KERNEL_XZ
+	select HAVE_KERNEL_ZSTD
 	select HAVE_KPROBES
 	select HAVE_KPROBES_ON_FTRACE
 	select HAVE_FUNCTION_ERROR_INJECTION
diff --git a/arch/x86/boot/compressed/Makefile b/arch/x86/boot/compressed/Makefile
index 466f66c8a7f8..6d2a8d2d378d 100644
--- a/arch/x86/boot/compressed/Makefile
+++ b/arch/x86/boot/compressed/Makefile
@@ -24,7 +24,7 @@ OBJECT_FILES_NON_STANDARD	:= y
 KCOV_INSTRUMENT		:= n
 
 targets := vmlinux vmlinux.bin vmlinux.bin.gz vmlinux.bin.bz2 vmlinux.bin.lzma \
-	vmlinux.bin.xz vmlinux.bin.lzo vmlinux.bin.lz4
+	vmlinux.bin.xz vmlinux.bin.lzo vmlinux.bin.lz4 vmlinux.bin.zst
 
 KBUILD_CFLAGS := -m$(BITS) -O2
 KBUILD_CFLAGS += -fno-strict-aliasing $(call cc-option, -fPIE, -fPIC)
@@ -142,6 +142,8 @@ $(obj)/vmlinux.bin.lzo: $(vmlinux.bin.all-y) FORCE
 	$(call if_changed,lzo)
 $(obj)/vmlinux.bin.lz4: $(vmlinux.bin.all-y) FORCE
 	$(call if_changed,lz4)
+$(obj)/vmlinux.bin.zst: $(vmlinux.bin.all-y) FORCE
+	$(call if_changed,zstd)
 
 suffix-$(CONFIG_KERNEL_GZIP)	:= gz
 suffix-$(CONFIG_KERNEL_BZIP2)	:= bz2
@@ -149,6 +151,7 @@ suffix-$(CONFIG_KERNEL_LZMA)	:= lzma
 suffix-$(CONFIG_KERNEL_XZ)	:= xz
 suffix-$(CONFIG_KERNEL_LZO) 	:= lzo
 suffix-$(CONFIG_KERNEL_LZ4) 	:= lz4
+suffix-$(CONFIG_KERNEL_ZSTD)	:= zst
 
 quiet_cmd_mkpiggy = MKPIGGY $@
       cmd_mkpiggy = $(obj)/mkpiggy $< > $@ || ( rm -f $@ ; false )
diff --git a/arch/x86/boot/compressed/misc.c b/arch/x86/boot/compressed/misc.c
index 8dd1d5ccae58..b6c8921100fb 100644
--- a/arch/x86/boot/compressed/misc.c
+++ b/arch/x86/boot/compressed/misc.c
@@ -76,6 +76,10 @@ static int lines, cols;
 #ifdef CONFIG_KERNEL_LZ4
 #include "../../../../lib/decompress_unlz4.c"
 #endif
+
+#ifdef CONFIG_KERNEL_ZSTD
+#include "../../../../lib/decompress_unzstd.c"
+#endif
 /*
  * NOTE: When adding a new decompressor, please update the analysis in
  * ../header.S.
diff --git a/arch/x86/boot/header.S b/arch/x86/boot/header.S
index 4c881c850125..af2efb256527 100644
--- a/arch/x86/boot/header.S
+++ b/arch/x86/boot/header.S
@@ -526,8 +526,14 @@ pref_address:		.quad LOAD_PHYSICAL_ADDR	# preferred load addr
 # the size-dependent part now grows so fast.
 #
 # extra_bytes = (uncompressed_size >> 8) + 65536
+#
+# ZSTD compressed data grows by at most 3 bytes per 128K, and only has a 22
+# byte fixed overhead but has a maximum block size of 128K, so it needs a
+# larger margin.
+#
+# extra_bytes = (uncompressed_size >> 8) + 131072
 
-#define ZO_z_extra_bytes	((ZO_z_output_len >> 8) + 65536)
+#define ZO_z_extra_bytes	((ZO_z_output_len >> 8) + 131072)
 #if ZO_z_output_len > ZO_z_input_len
 # define ZO_z_extract_offset	(ZO_z_output_len + ZO_z_extra_bytes - \
 				 ZO_z_input_len)
diff --git a/arch/x86/include/asm/boot.h b/arch/x86/include/asm/boot.h
index 680c320363db..d6dd43d25d9f 100644
--- a/arch/x86/include/asm/boot.h
+++ b/arch/x86/include/asm/boot.h
@@ -24,9 +24,11 @@
 # error "Invalid value for CONFIG_PHYSICAL_ALIGN"
 #endif
 
-#ifdef CONFIG_KERNEL_BZIP2
+#if defined(CONFIG_KERNEL_BZIP2)
 # define BOOT_HEAP_SIZE		0x400000
-#else /* !CONFIG_KERNEL_BZIP2 */
+#elif defined(CONFIG_KERNEL_ZSTD)
+# define BOOT_HEAP_SIZE		 0x30000
+#else
 # define BOOT_HEAP_SIZE		 0x10000
 #endif
 
-- 
2.19.1

Re: [PATCH 02/17] x86: Add support for ZSTD-compressed kernel

[Ingo Molnar]

* Adam Borowski <kilobyte@angband.pl> wrote:

> From: Nick Terrell <terrelln@fb.com>
> 
> Integrates the ZSTD decompression code to the x86 pre-boot code.
> 
> Zstandard requires slightly more memory during the kernel decompression
> on x86 (192 KB vs 64 KB), and the memory usage is independent of the
> window size.
> 
> Zstandard requires memory proportional to the window size used during
> compression for decompressing the ramdisk image, since streaming mode is
> used. Newer versions of zstd (1.3.2+) list the window size of a file
> with `zstd -lv <file>'. The absolute maximum amount of memory required
> is just over 8 MB.
> 
> Signed-off-by: Nick Terrell <terrelln@fb.com>
> ---
>  Documentation/x86/boot.txt        | 6 +++---
>  arch/x86/Kconfig                  | 1 +
>  arch/x86/boot/compressed/Makefile | 5 ++++-
>  arch/x86/boot/compressed/misc.c   | 4 ++++
>  arch/x86/boot/header.S            | 8 +++++++-
>  arch/x86/include/asm/boot.h       | 6 ++++--
>  6 files changed, 23 insertions(+), 7 deletions(-)

Acked-by: Ingo Molnar <mingo@kernel.org>

> diff --git a/arch/x86/boot/header.S b/arch/x86/boot/header.S
> index 4c881c850125..af2efb256527 100644
> --- a/arch/x86/boot/header.S
> +++ b/arch/x86/boot/header.S
> @@ -526,8 +526,14 @@ pref_address:		.quad LOAD_PHYSICAL_ADDR	# preferred load addr
>  # the size-dependent part now grows so fast.
>  #
>  # extra_bytes = (uncompressed_size >> 8) + 65536
> +#
> +# ZSTD compressed data grows by at most 3 bytes per 128K, and only has a 22
> +# byte fixed overhead but has a maximum block size of 128K, so it needs a
> +# larger margin.
> +#
> +# extra_bytes = (uncompressed_size >> 8) + 131072
>  
> -#define ZO_z_extra_bytes	((ZO_z_output_len >> 8) + 65536)
> +#define ZO_z_extra_bytes	((ZO_z_output_len >> 8) + 131072)

This change would also affect other decompressors, not just ZSTD, 
correct?

Might want to split this change out into a separate preparatory patch to 
allow it to be bisected to, or at least mention it in the changelog more 
explicitly?

Thanks,

	Ingo

[PATCH 03/17] .gitignore: add ZSTD-compressed files

[Adam Borowski]

For now, that's arch/x86/boot/compressed/vmlinux.bin.zst but probably more
will come, thus let's be consistent with all other compressors.

Signed-off-by: Adam Borowski <kilobyte@angband.pl>
---
 .gitignore | 1 +
 1 file changed, 1 insertion(+)

diff --git a/.gitignore b/.gitignore
index 97ba6b79834c..0d09cf1c053c 100644
--- a/.gitignore
+++ b/.gitignore
@@ -42,6 +42,7 @@
 *.tab.[ch]
 *.tar
 *.xz
+*.zst
 Module.symvers
 modules.builtin
 
-- 
2.19.1

[PATCH 04/17] x86: Remove support for BZIP2 and LZMA compressed kernel

[Adam Borowski]

While bzip2 used to be good in its heyday, it's been drastically eclipsed
by newer algorithms.  In no case it's a rational choice anymore -- at any
point of the size-to-compression curve, there's something much better.
As we control the build process, any .configs that still select it will
harmlessly be adjusted, thus there's no risk of breakage.

Bare lzma is redundant with xz, lacks some improvements, and uses its own
copy of code instead using the common library.

Signed-off-by: Adam Borowski <kilobyte@angband.pl>
---
 Documentation/x86/boot.txt        | 11 +++++------
 arch/x86/Kconfig                  |  2 --
 arch/x86/boot/compressed/Makefile | 12 +++---------
 arch/x86/boot/compressed/misc.c   |  8 --------
 arch/x86/include/asm/boot.h       |  4 +---
 5 files changed, 9 insertions(+), 28 deletions(-)

diff --git a/Documentation/x86/boot.txt b/Documentation/x86/boot.txt
index a47b6bae3356..fbd9720989e5 100644
--- a/Documentation/x86/boot.txt
+++ b/Documentation/x86/boot.txt
@@ -682,12 +682,11 @@ Protocol:	2.08+
   of the protected-mode code to the payload.
 
   The payload may be compressed. The format of both the compressed and
-  uncompressed data should be determined using the standard magic
-  numbers.  The currently supported compression formats are gzip
-  (magic numbers 1F 8B or 1F 9E), bzip2 (magic number 42 5A), LZMA
-  (magic number 5D 00), XZ (magic number FD 37), LZ4 (magic number
-  02 21) and ZSTD (magic number 28 B5). The uncompressed payload is
-  currently always ELF (magic number 7F 45 4C 46).
+  uncompressed data should be determined using the standard magic numbers.
+  The currently supported compression formats are gzip (magic numbers 1F 8B
+  or 1F 9E), XZ (magic number FD 37), LZ4 (magic number 02 21) and ZSTD
+  (magic number 28 B5). The uncompressed payload is currently always ELF
+  (magic number 7F 45 4C 46).
 
 Field name:	payload_length
 Type:		read
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 203f7467f5c4..a47af31bbc62 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -158,10 +158,8 @@ config X86
 	select HAVE_IOREMAP_PROT
 	select HAVE_IRQ_EXIT_ON_IRQ_STACK	if X86_64
 	select HAVE_IRQ_TIME_ACCOUNTING
-	select HAVE_KERNEL_BZIP2
 	select HAVE_KERNEL_GZIP
 	select HAVE_KERNEL_LZ4
-	select HAVE_KERNEL_LZMA
 	select HAVE_KERNEL_LZO
 	select HAVE_KERNEL_XZ
 	select HAVE_KERNEL_ZSTD
diff --git a/arch/x86/boot/compressed/Makefile b/arch/x86/boot/compressed/Makefile
index 6d2a8d2d378d..763aeb850658 100644
--- a/arch/x86/boot/compressed/Makefile
+++ b/arch/x86/boot/compressed/Makefile
@@ -7,13 +7,13 @@
 # vmlinuz is:
 #	decompression code (*.o)
 #	asm globals (piggy.S), including:
-#		vmlinux.bin.(gz|bz2|lzma|...)
+#		vmlinux.bin.(gz|zst|xz|...)
 #
 # vmlinux.bin is:
 #	vmlinux stripped of debugging and comments
 # vmlinux.bin.all is:
 #	vmlinux.bin + vmlinux.relocs
-# vmlinux.bin.(gz|bz2|lzma|...) is:
+# vmlinux.bin.(gz|zst|xz|...) is:
 #	(see scripts/Makefile.lib size_append)
 #	compressed vmlinux.bin.all + u32 size of vmlinux.bin.all
 
@@ -23,7 +23,7 @@ OBJECT_FILES_NON_STANDARD	:= y
 # Prevents link failures: __sanitizer_cov_trace_pc() is not linked in.
 KCOV_INSTRUMENT		:= n
 
-targets := vmlinux vmlinux.bin vmlinux.bin.gz vmlinux.bin.bz2 vmlinux.bin.lzma \
+targets := vmlinux vmlinux.bin vmlinux.bin.gz \
 	vmlinux.bin.xz vmlinux.bin.lzo vmlinux.bin.lz4 vmlinux.bin.zst
 
 KBUILD_CFLAGS := -m$(BITS) -O2
@@ -132,10 +132,6 @@ vmlinux.bin.all-$(CONFIG_X86_NEED_RELOCS) += $(obj)/vmlinux.relocs
 
 $(obj)/vmlinux.bin.gz: $(vmlinux.bin.all-y) FORCE
 	$(call if_changed,gzip)
-$(obj)/vmlinux.bin.bz2: $(vmlinux.bin.all-y) FORCE
-	$(call if_changed,bzip2)
-$(obj)/vmlinux.bin.lzma: $(vmlinux.bin.all-y) FORCE
-	$(call if_changed,lzma)
 $(obj)/vmlinux.bin.xz: $(vmlinux.bin.all-y) FORCE
 	$(call if_changed,xzkern)
 $(obj)/vmlinux.bin.lzo: $(vmlinux.bin.all-y) FORCE
@@ -146,8 +142,6 @@ $(obj)/vmlinux.bin.zst: $(vmlinux.bin.all-y) FORCE
 	$(call if_changed,zstd)
 
 suffix-$(CONFIG_KERNEL_GZIP)	:= gz
-suffix-$(CONFIG_KERNEL_BZIP2)	:= bz2
-suffix-$(CONFIG_KERNEL_LZMA)	:= lzma
 suffix-$(CONFIG_KERNEL_XZ)	:= xz
 suffix-$(CONFIG_KERNEL_LZO) 	:= lzo
 suffix-$(CONFIG_KERNEL_LZ4) 	:= lz4
diff --git a/arch/x86/boot/compressed/misc.c b/arch/x86/boot/compressed/misc.c
index b6c8921100fb..c0d75b74f199 100644
--- a/arch/x86/boot/compressed/misc.c
+++ b/arch/x86/boot/compressed/misc.c
@@ -57,14 +57,6 @@ static int lines, cols;
 #include "../../../../lib/decompress_inflate.c"
 #endif
 
-#ifdef CONFIG_KERNEL_BZIP2
-#include "../../../../lib/decompress_bunzip2.c"
-#endif
-
-#ifdef CONFIG_KERNEL_LZMA
-#include "../../../../lib/decompress_unlzma.c"
-#endif
-
 #ifdef CONFIG_KERNEL_XZ
 #include "../../../../lib/decompress_unxz.c"
 #endif
diff --git a/arch/x86/include/asm/boot.h b/arch/x86/include/asm/boot.h
index d6dd43d25d9f..afbf3d60f22e 100644
--- a/arch/x86/include/asm/boot.h
+++ b/arch/x86/include/asm/boot.h
@@ -24,9 +24,7 @@
 # error "Invalid value for CONFIG_PHYSICAL_ALIGN"
 #endif
 
-#if defined(CONFIG_KERNEL_BZIP2)
-# define BOOT_HEAP_SIZE		0x400000
-#elif defined(CONFIG_KERNEL_ZSTD)
+#if defined(CONFIG_KERNEL_ZSTD)
 # define BOOT_HEAP_SIZE		 0x30000
 #else
 # define BOOT_HEAP_SIZE		 0x10000
-- 
2.19.1

[PATCH 05/17] mips: Remove support for BZIP2 and LZMA compressed kernel

[Adam Borowski]

Made redundant by newer choices.

Signed-off-by: Adam Borowski <kilobyte@angband.pl>
---
 arch/mips/Kconfig                      |  2 --
 arch/mips/boot/Makefile                | 27 --------------------------
 arch/mips/boot/compressed/Makefile     |  2 --
 arch/mips/boot/compressed/decompress.c |  8 --------
 4 files changed, 39 deletions(-)

diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
index 8272ea4c7264..8f774bb9d22f 100644
--- a/arch/mips/Kconfig
+++ b/arch/mips/Kconfig
@@ -1834,9 +1834,7 @@ endif # CPU_LOONGSON2F
 config SYS_SUPPORTS_ZBOOT
 	bool
 	select HAVE_KERNEL_GZIP
-	select HAVE_KERNEL_BZIP2
 	select HAVE_KERNEL_LZ4
-	select HAVE_KERNEL_LZMA
 	select HAVE_KERNEL_LZO
 	select HAVE_KERNEL_XZ
 
diff --git a/arch/mips/boot/Makefile b/arch/mips/boot/Makefile
index 35704c28a28b..9c5f380a6c20 100644
--- a/arch/mips/boot/Makefile
+++ b/arch/mips/boot/Makefile
@@ -24,9 +24,7 @@ strip-flags   := $(addprefix --remove-section=,$(drop-sections))
 hostprogs-y := elf2ecoff
 
 suffix-y			:= bin
-suffix-$(CONFIG_KERNEL_BZIP2)	:= bz2
 suffix-$(CONFIG_KERNEL_GZIP)	:= gz
-suffix-$(CONFIG_KERNEL_LZMA)	:= lzma
 suffix-$(CONFIG_KERNEL_LZO)	:= lzo
 
 targets := vmlinux.ecoff
@@ -54,20 +52,12 @@ UIMAGE_ENTRYADDR = $(VMLINUX_ENTRY_ADDRESS)
 # Compressed vmlinux images
 #
 
-extra-y += vmlinux.bin.bz2
 extra-y += vmlinux.bin.gz
-extra-y += vmlinux.bin.lzma
 extra-y += vmlinux.bin.lzo
 
-$(obj)/vmlinux.bin.bz2: $(obj)/vmlinux.bin FORCE
-	$(call if_changed,bzip2)
-
 $(obj)/vmlinux.bin.gz: $(obj)/vmlinux.bin FORCE
 	$(call if_changed,gzip)
 
-$(obj)/vmlinux.bin.lzma: $(obj)/vmlinux.bin FORCE
-	$(call if_changed,lzma)
-
 $(obj)/vmlinux.bin.lzo: $(obj)/vmlinux.bin FORCE
 	$(call if_changed,lzo)
 
@@ -77,23 +67,15 @@ $(obj)/vmlinux.bin.lzo: $(obj)/vmlinux.bin FORCE
 
 targets += uImage
 targets += uImage.bin
-targets += uImage.bz2
 targets += uImage.gz
-targets += uImage.lzma
 targets += uImage.lzo
 
 $(obj)/uImage.bin: $(obj)/vmlinux.bin FORCE
 	$(call if_changed,uimage,none)
 
-$(obj)/uImage.bz2: $(obj)/vmlinux.bin.bz2 FORCE
-	$(call if_changed,uimage,bzip2)
-
 $(obj)/uImage.gz: $(obj)/vmlinux.bin.gz FORCE
 	$(call if_changed,uimage,gzip)
 
-$(obj)/uImage.lzma: $(obj)/vmlinux.bin.lzma FORCE
-	$(call if_changed,uimage,lzma)
-
 $(obj)/uImage.lzo: $(obj)/vmlinux.bin.lzo FORCE
 	$(call if_changed,uimage,lzo)
 
@@ -122,7 +104,6 @@ $(obj)/vmlinux.its.S: $(addprefix $(srctree)/arch/mips/$(PLATFORM)/,$(ITS_INPUTS
 
 targets += vmlinux.its
 targets += vmlinux.gz.its
-targets += vmlinux.bz2.its
 targets += vmlinux.lzmo.its
 targets += vmlinux.lzo.its
 
@@ -142,19 +123,11 @@ $(obj)/vmlinux.its: $(obj)/vmlinux.its.S $(VMLINUX) FORCE
 $(obj)/vmlinux.gz.its: $(obj)/vmlinux.its.S $(VMLINUX) FORCE
 	$(call if_changed,cpp_its_S,gzip,vmlinux.bin.gz)
 
-$(obj)/vmlinux.bz2.its: $(obj)/vmlinux.its.S $(VMLINUX)  FORCE
-	$(call if_changed,cpp_its_S,bzip2,vmlinux.bin.bz2)
-
-$(obj)/vmlinux.lzma.its: $(obj)/vmlinux.its.S $(VMLINUX) FORCE
-	$(call if_changed,cpp_its_S,lzma,vmlinux.bin.lzma)
-
 $(obj)/vmlinux.lzo.its: $(obj)/vmlinux.its.S $(VMLINUX) FORCE
 	$(call if_changed,cpp_its_S,lzo,vmlinux.bin.lzo)
 
 targets += vmlinux.itb
 targets += vmlinux.gz.itb
-targets += vmlinux.bz2.itb
-targets += vmlinux.lzma.itb
 targets += vmlinux.lzo.itb
 
 quiet_cmd_itb-image = ITB     $@
diff --git a/arch/mips/boot/compressed/Makefile b/arch/mips/boot/compressed/Makefile
index 3c453a1f1ff1..a7448d74fe7b 100644
--- a/arch/mips/boot/compressed/Makefile
+++ b/arch/mips/boot/compressed/Makefile
@@ -62,9 +62,7 @@ $(obj)/vmlinux.bin: $(KBUILD_IMAGE) FORCE
 	$(call if_changed,objcopy)
 
 tool_$(CONFIG_KERNEL_GZIP)    = gzip
-tool_$(CONFIG_KERNEL_BZIP2)   = bzip2
 tool_$(CONFIG_KERNEL_LZ4)     = lz4
-tool_$(CONFIG_KERNEL_LZMA)    = lzma
 tool_$(CONFIG_KERNEL_LZO)     = lzo
 tool_$(CONFIG_KERNEL_XZ)      = xzkern
 
diff --git a/arch/mips/boot/compressed/decompress.c b/arch/mips/boot/compressed/decompress.c
index 81df9047e110..ac6978d210e6 100644
--- a/arch/mips/boot/compressed/decompress.c
+++ b/arch/mips/boot/compressed/decompress.c
@@ -56,18 +56,10 @@ void error(char *x)
 #include "../../../../lib/decompress_inflate.c"
 #endif
 
-#ifdef CONFIG_KERNEL_BZIP2
-#include "../../../../lib/decompress_bunzip2.c"
-#endif
-
 #ifdef CONFIG_KERNEL_LZ4
 #include "../../../../lib/decompress_unlz4.c"
 #endif
 
-#ifdef CONFIG_KERNEL_LZMA
-#include "../../../../lib/decompress_unlzma.c"
-#endif
-
 #ifdef CONFIG_KERNEL_LZO
 #include "../../../../lib/decompress_unlzo.c"
 #endif
-- 
2.19.1

Re: [PATCH 05/17] mips: Remove support for BZIP2 and LZMA compressed kernel

[Paul Burton]

Hi Adam,

On Fri, Nov 09, 2018 at 08:02:52PM +0100, Adam Borowski wrote:
> @@ -122,7 +104,6 @@ $(obj)/vmlinux.its.S: $(addprefix $(srctree)/arch/mips/$(PLATFORM)/,$(ITS_INPUTS
>  
>  targets += vmlinux.its
>  targets += vmlinux.gz.its
> -targets += vmlinux.bz2.its
>  targets += vmlinux.lzmo.its
>  targets += vmlinux.lzo.its

It looks to me like this "vmlinux.lzmo.its" was a typo & ought to have
been vmlinux.lzma.its, and thus ought to be removed.

Apart from that I'm fine with this in general:

    Acked-by: Paul Burton <paul.burton@mips.com>

Thanks,
    Paul

Re: [PATCH 05/17] mips: Remove support for BZIP2 and LZMA compressed kernel

[Adam Borowski]

On Tue, Nov 13, 2018 at 10:45:54PM +0000, Paul Burton wrote:
> On Fri, Nov 09, 2018 at 08:02:52PM +0100, Adam Borowski wrote:
> > @@ -122,7 +104,6 @@ $(obj)/vmlinux.its.S: $(addprefix $(srctree)/arch/mips/$(PLATFORM)/,$(ITS_INPUTS
> >  
> >  targets += vmlinux.its
> >  targets += vmlinux.gz.its
> > -targets += vmlinux.bz2.its
> >  targets += vmlinux.lzmo.its
> >  targets += vmlinux.lzo.its
> 
> It looks to me like this "vmlinux.lzmo.its" was a typo & ought to have
> been vmlinux.lzma.its, and thus ought to be removed.

Good catch!

The whole series was bz2 only at first, grepping for lzma missed this.

> Apart from that I'm fine with this in general:
> 
>     Acked-by: Paul Burton <paul.burton@mips.com>

Thanks.


Meow!
-- 
⢀⣴⠾⠻⢶⣦⠀
⣾⠁⢰⠒⠀⣿⡁ “This is gonna be as easy as cheating on an ethics exam!”
⢿⡄⠘⠷⠚⠋⠀     -Cerise Brightmoon
⠈⠳⣄⠀⠀⠀⠀

[PATCH 06/17] parisc: Remove support for BZIP2 and LZMA compressed kernel

[Adam Borowski]

Made redundant by newer choices.

Signed-off-by: Adam Borowski <kilobyte@angband.pl>
---
 arch/parisc/Kconfig                  |  2 --
 arch/parisc/boot/compressed/Makefile | 10 ++--------
 arch/parisc/boot/compressed/misc.c   |  8 --------
 3 files changed, 2 insertions(+), 18 deletions(-)

diff --git a/arch/parisc/Kconfig b/arch/parisc/Kconfig
index 92a339ee28b3..a9cca7d1a8d8 100644
--- a/arch/parisc/Kconfig
+++ b/arch/parisc/Kconfig
@@ -18,10 +18,8 @@ config PARISC
 	select BUG
 	select BUILDTIME_EXTABLE_SORT
 	select HAVE_PERF_EVENTS
-	select HAVE_KERNEL_BZIP2
 	select HAVE_KERNEL_GZIP
 	select HAVE_KERNEL_LZ4
-	select HAVE_KERNEL_LZMA
 	select HAVE_KERNEL_LZO
 	select HAVE_KERNEL_XZ
 	select GENERIC_ATOMIC64 if !64BIT
diff --git a/arch/parisc/boot/compressed/Makefile b/arch/parisc/boot/compressed/Makefile
index 777533cdea31..a05f36f9279b 100644
--- a/arch/parisc/boot/compressed/Makefile
+++ b/arch/parisc/boot/compressed/Makefile
@@ -8,8 +8,8 @@ KCOV_INSTRUMENT := n
 GCOV_PROFILE := n
 UBSAN_SANITIZE := n
 
-targets := vmlinux.lds vmlinux vmlinux.bin vmlinux.bin.gz vmlinux.bin.bz2
-targets += vmlinux.bin.xz vmlinux.bin.lzma vmlinux.bin.lzo vmlinux.bin.lz4
+targets := vmlinux.lds vmlinux vmlinux.bin vmlinux.bin.gz
+targets += vmlinux.bin.xz vmlinux.bin.lzo vmlinux.bin.lz4
 targets += misc.o piggy.o sizes.h head.o real2.o firmware.o
 
 KBUILD_CFLAGS := -D__KERNEL__ -O2 -DBOOTLOADER
@@ -60,20 +60,14 @@ $(obj)/vmlinux.bin: vmlinux
 vmlinux.bin.all-y := $(obj)/vmlinux.bin
 
 suffix-$(CONFIG_KERNEL_GZIP)  := gz
-suffix-$(CONFIG_KERNEL_BZIP2) := bz2
 suffix-$(CONFIG_KERNEL_LZ4)  := lz4
-suffix-$(CONFIG_KERNEL_LZMA)  := lzma
 suffix-$(CONFIG_KERNEL_LZO)  := lzo
 suffix-$(CONFIG_KERNEL_XZ)  := xz
 
 $(obj)/vmlinux.bin.gz: $(vmlinux.bin.all-y)
 	$(call if_changed,gzip)
-$(obj)/vmlinux.bin.bz2: $(vmlinux.bin.all-y)
-	$(call if_changed,bzip2)
 $(obj)/vmlinux.bin.lz4: $(vmlinux.bin.all-y)
 	$(call if_changed,lz4)
-$(obj)/vmlinux.bin.lzma: $(vmlinux.bin.all-y)
-	$(call if_changed,lzma)
 $(obj)/vmlinux.bin.lzo: $(vmlinux.bin.all-y)
 	$(call if_changed,lzo)
 $(obj)/vmlinux.bin.xz: $(vmlinux.bin.all-y)
diff --git a/arch/parisc/boot/compressed/misc.c b/arch/parisc/boot/compressed/misc.c
index 2556bb181813..1ca59916071e 100644
--- a/arch/parisc/boot/compressed/misc.c
+++ b/arch/parisc/boot/compressed/misc.c
@@ -42,18 +42,10 @@ static unsigned long free_mem_end_ptr;
 #include "../../../../lib/decompress_inflate.c"
 #endif
 
-#ifdef CONFIG_KERNEL_BZIP2
-#include "../../../../lib/decompress_bunzip2.c"
-#endif
-
 #ifdef CONFIG_KERNEL_LZ4
 #include "../../../../lib/decompress_unlz4.c"
 #endif
 
-#ifdef CONFIG_KERNEL_LZMA
-#include "../../../../lib/decompress_unlzma.c"
-#endif
-
 #ifdef CONFIG_KERNEL_LZO
 #include "../../../../lib/decompress_unlzo.c"
 #endif
-- 
2.19.1

[PATCH 07/17] s390: Remove support for BZIP2 and LZMA compressed kernel

[Adam Borowski]

Made redundant by newer choices.

Signed-off-by: Adam Borowski <kilobyte@angband.pl>
---
 arch/s390/Kconfig                        | 2 --
 arch/s390/boot/compressed/Makefile       | 8 +-------
 arch/s390/boot/compressed/decompressor.c | 8 --------
 3 files changed, 1 insertion(+), 17 deletions(-)

diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
index 5173366af8f3..96adb6127246 100644
--- a/arch/s390/Kconfig
+++ b/arch/s390/Kconfig
@@ -150,10 +150,8 @@ config S390
 	select HAVE_FUNCTION_TRACER
 	select HAVE_FUTEX_CMPXCHG if FUTEX
 	select HAVE_GCC_PLUGINS
-	select HAVE_KERNEL_BZIP2
 	select HAVE_KERNEL_GZIP
 	select HAVE_KERNEL_LZ4
-	select HAVE_KERNEL_LZMA
 	select HAVE_KERNEL_LZO
 	select HAVE_KERNEL_UNCOMPRESSED
 	select HAVE_KERNEL_XZ
diff --git a/arch/s390/boot/compressed/Makefile b/arch/s390/boot/compressed/Makefile
index 593039620487..ddd9d44fb7a8 100644
--- a/arch/s390/boot/compressed/Makefile
+++ b/arch/s390/boot/compressed/Makefile
@@ -11,7 +11,7 @@ UBSAN_SANITIZE := n
 KASAN_SANITIZE := n
 
 obj-y	:= $(if $(CONFIG_KERNEL_UNCOMPRESSED),,decompressor.o) piggy.o info.o
-targets	:= vmlinux.lds vmlinux vmlinux.bin vmlinux.bin.gz vmlinux.bin.bz2
+targets	:= vmlinux.lds vmlinux vmlinux.bin vmlinux.bin.gz
 targets += vmlinux.bin.xz vmlinux.bin.lzma vmlinux.bin.lzo vmlinux.bin.lz4
 targets += info.bin $(obj-y)
 
@@ -40,20 +40,14 @@ $(obj)/vmlinux.bin: vmlinux FORCE
 vmlinux.bin.all-y := $(obj)/vmlinux.bin
 
 suffix-$(CONFIG_KERNEL_GZIP)  := .gz
-suffix-$(CONFIG_KERNEL_BZIP2) := .bz2
 suffix-$(CONFIG_KERNEL_LZ4)  := .lz4
-suffix-$(CONFIG_KERNEL_LZMA)  := .lzma
 suffix-$(CONFIG_KERNEL_LZO)  := .lzo
 suffix-$(CONFIG_KERNEL_XZ)  := .xz
 
 $(obj)/vmlinux.bin.gz: $(vmlinux.bin.all-y)
 	$(call if_changed,gzip)
-$(obj)/vmlinux.bin.bz2: $(vmlinux.bin.all-y)
-	$(call if_changed,bzip2)
 $(obj)/vmlinux.bin.lz4: $(vmlinux.bin.all-y)
 	$(call if_changed,lz4)
-$(obj)/vmlinux.bin.lzma: $(vmlinux.bin.all-y)
-	$(call if_changed,lzma)
 $(obj)/vmlinux.bin.lzo: $(vmlinux.bin.all-y)
 	$(call if_changed,lzo)
 $(obj)/vmlinux.bin.xz: $(vmlinux.bin.all-y)
diff --git a/arch/s390/boot/compressed/decompressor.c b/arch/s390/boot/compressed/decompressor.c
index 45046630c56a..3995a6fe60f5 100644
--- a/arch/s390/boot/compressed/decompressor.c
+++ b/arch/s390/boot/compressed/decompressor.c
@@ -42,18 +42,10 @@ static unsigned long free_mem_end_ptr = (unsigned long) _end + HEAP_SIZE;
 #include "../../../../lib/decompress_inflate.c"
 #endif
 
-#ifdef CONFIG_KERNEL_BZIP2
-#include "../../../../lib/decompress_bunzip2.c"
-#endif
-
 #ifdef CONFIG_KERNEL_LZ4
 #include "../../../../lib/decompress_unlz4.c"
 #endif
 
-#ifdef CONFIG_KERNEL_LZMA
-#include "../../../../lib/decompress_unlzma.c"
-#endif
-
 #ifdef CONFIG_KERNEL_LZO
 #include "../../../../lib/decompress_unlzo.c"
 #endif
-- 
2.19.1

[PATCH 08/17] sh: Remove support for BZIP2 and LZMA compressed kernel

[Adam Borowski]

Made redundant by newer choices.

Signed-off-by: Adam Borowski <kilobyte@angband.pl>
---
 arch/sh/Kconfig                  |  2 --
 arch/sh/Makefile                 |  4 +---
 arch/sh/boot/Makefile            | 19 ++-----------------
 arch/sh/boot/compressed/Makefile |  5 -----
 arch/sh/boot/compressed/misc.c   | 12 ------------
 5 files changed, 3 insertions(+), 39 deletions(-)

diff --git a/arch/sh/Kconfig b/arch/sh/Kconfig
index f82a4da7adf3..fbb2e17275d1 100644
--- a/arch/sh/Kconfig
+++ b/arch/sh/Kconfig
@@ -23,8 +23,6 @@ config SUPERH
 	select HAVE_DEBUG_KMEMLEAK
 	select HAVE_KERNEL_GZIP
 	select CPU_NO_EFFICIENT_FFS
-	select HAVE_KERNEL_BZIP2
-	select HAVE_KERNEL_LZMA
 	select HAVE_KERNEL_XZ
 	select HAVE_KERNEL_LZO
 	select HAVE_UID16
diff --git a/arch/sh/Makefile b/arch/sh/Makefile
index c521ade2557c..70925d0cd2a8 100644
--- a/arch/sh/Makefile
+++ b/arch/sh/Makefile
@@ -209,7 +209,7 @@ endif
 libs-$(CONFIG_SUPERH32)		:= arch/sh/lib/	$(libs-y)
 libs-$(CONFIG_SUPERH64)		:= arch/sh/lib64/ $(libs-y)
 
-BOOT_TARGETS = uImage uImage.bz2 uImage.gz uImage.lzma uImage.xz uImage.lzo \
+BOOT_TARGETS = uImage uImage.bz2 uImage.gz uImage.xz uImage.lzo \
 	       uImage.srec uImage.bin zImage vmlinux.bin vmlinux.srec \
 	       romImage
 PHONY += $(BOOT_TARGETS)
@@ -237,8 +237,6 @@ define archhelp
 	@echo '  uImage.srec	           - Create an S-record for U-Boot'
 	@echo '  uImage.bin	           - Kernel-only image for U-Boot (bin)'
 	@echo '* uImage.gz	           - Kernel-only image for U-Boot (gzip)'
-	@echo '  uImage.bz2	           - Kernel-only image for U-Boot (bzip2)'
-	@echo '  uImage.lzma	           - Kernel-only image for U-Boot (lzma)'
 	@echo '  uImage.xz	           - Kernel-only image for U-Boot (xz)'
 	@echo '  uImage.lzo	           - Kernel-only image for U-Boot (lzo)'
 endef
diff --git a/arch/sh/boot/Makefile b/arch/sh/boot/Makefile
index 58592dfa5cb6..bf8cf598a5ab 100644
--- a/arch/sh/boot/Makefile
+++ b/arch/sh/boot/Makefile
@@ -21,15 +21,12 @@ CONFIG_PHYSICAL_START	?= $(CONFIG_MEMORY_START)
 
 suffix-y := bin
 suffix-$(CONFIG_KERNEL_GZIP)	:= gz
-suffix-$(CONFIG_KERNEL_BZIP2)	:= bz2
-suffix-$(CONFIG_KERNEL_LZMA)	:= lzma
 suffix-$(CONFIG_KERNEL_XZ)	:= xz
 suffix-$(CONFIG_KERNEL_LZO)	:= lzo
 
 targets := zImage vmlinux.srec romImage uImage uImage.srec uImage.gz \
-	   uImage.bz2 uImage.lzma uImage.xz uImage.lzo uImage.bin
-extra-y += vmlinux.bin vmlinux.bin.gz vmlinux.bin.bz2 vmlinux.bin.lzma \
-	   vmlinux.bin.xz vmlinux.bin.lzo
+	   uImage.xz uImage.lzo uImage.bin
+extra-y += vmlinux.bin vmlinux.bin.gz vmlinux.bin.xz vmlinux.bin.lzo
 subdir- := compressed romimage
 
 $(obj)/zImage: $(obj)/compressed/vmlinux FORCE
@@ -68,27 +65,15 @@ $(obj)/vmlinux.bin: vmlinux FORCE
 $(obj)/vmlinux.bin.gz: $(obj)/vmlinux.bin FORCE
 	$(call if_changed,gzip)
 
-$(obj)/vmlinux.bin.bz2: $(obj)/vmlinux.bin FORCE
-	$(call if_changed,bzip2)
-
-$(obj)/vmlinux.bin.lzma: $(obj)/vmlinux.bin FORCE
-	$(call if_changed,lzma)
-
 $(obj)/vmlinux.bin.xz: $(obj)/vmlinux.bin FORCE
 	$(call if_changed,xzkern)
 
 $(obj)/vmlinux.bin.lzo: $(obj)/vmlinux.bin FORCE
 	$(call if_changed,lzo)
 
-$(obj)/uImage.bz2: $(obj)/vmlinux.bin.bz2
-	$(call if_changed,uimage,bzip2)
-
 $(obj)/uImage.gz: $(obj)/vmlinux.bin.gz
 	$(call if_changed,uimage,gzip)
 
-$(obj)/uImage.lzma: $(obj)/vmlinux.bin.lzma
-	$(call if_changed,uimage,lzma)
-
 $(obj)/uImage.xz: $(obj)/vmlinux.bin.xz
 	$(call if_changed,uimage,xz)
 
diff --git a/arch/sh/boot/compressed/Makefile b/arch/sh/boot/compressed/Makefile
index f5e1bd779789..abd33fd0d525 100644
--- a/arch/sh/boot/compressed/Makefile
+++ b/arch/sh/boot/compressed/Makefile
@@ -6,7 +6,6 @@
 #
 
 targets		:= vmlinux vmlinux.bin vmlinux.bin.gz \
-		   vmlinux.bin.bz2 vmlinux.bin.lzma \
 		   vmlinux.bin.xz vmlinux.bin.lzo \
 		   head_$(BITS).o misc.o piggy.o
 
@@ -64,10 +63,6 @@ vmlinux.bin.all-y := $(obj)/vmlinux.bin
 
 $(obj)/vmlinux.bin.gz: $(vmlinux.bin.all-y) FORCE
 	$(call if_changed,gzip)
-$(obj)/vmlinux.bin.bz2: $(vmlinux.bin.all-y) FORCE
-	$(call if_changed,bzip2)
-$(obj)/vmlinux.bin.lzma: $(vmlinux.bin.all-y) FORCE
-	$(call if_changed,lzma)
 $(obj)/vmlinux.bin.xz: $(vmlinux.bin.all-y) FORCE
 	$(call if_changed,xzkern)
 $(obj)/vmlinux.bin.lzo: $(vmlinux.bin.all-y) FORCE
diff --git a/arch/sh/boot/compressed/misc.c b/arch/sh/boot/compressed/misc.c
index c15cac9251b9..c82402add51e 100644
--- a/arch/sh/boot/compressed/misc.c
+++ b/arch/sh/boot/compressed/misc.c
@@ -44,24 +44,12 @@ extern int _end;
 static unsigned long free_mem_ptr;
 static unsigned long free_mem_end_ptr;
 
-#ifdef CONFIG_HAVE_KERNEL_BZIP2
-#define HEAP_SIZE	0x400000
-#else
 #define HEAP_SIZE	0x10000
-#endif
 
 #ifdef CONFIG_KERNEL_GZIP
 #include "../../../../lib/decompress_inflate.c"
 #endif
 
-#ifdef CONFIG_KERNEL_BZIP2
-#include "../../../../lib/decompress_bunzip2.c"
-#endif
-
-#ifdef CONFIG_KERNEL_LZMA
-#include "../../../../lib/decompress_unlzma.c"
-#endif
-
 #ifdef CONFIG_KERNEL_XZ
 #include "../../../../lib/decompress_unxz.c"
 #endif
-- 
2.19.1

[PATCH 09/17] unicore32: Remove support for BZIP2 and LZMA compressed kernel

[Adam Borowski]

Made redundant by newer choices -- sort of, as no one enabled support
for XZ nor ZSTD for unicore yet...

Signed-off-by: Adam Borowski <kilobyte@angband.pl>
---
 arch/unicore32/Kconfig                  | 2 --
 arch/unicore32/boot/compressed/Makefile | 4 +---
 arch/unicore32/boot/compressed/misc.c   | 8 --------
 3 files changed, 1 insertion(+), 13 deletions(-)

diff --git a/arch/unicore32/Kconfig b/arch/unicore32/Kconfig
index a4c05159dca5..b7eb7e9fb0d2 100644
--- a/arch/unicore32/Kconfig
+++ b/arch/unicore32/Kconfig
@@ -7,10 +7,8 @@ config UNICORE32
 	select DMA_DIRECT_OPS
 	select HAVE_GENERIC_DMA_COHERENT
 	select HAVE_KERNEL_GZIP
-	select HAVE_KERNEL_BZIP2
 	select GENERIC_ATOMIC64
 	select HAVE_KERNEL_LZO
-	select HAVE_KERNEL_LZMA
 	select VIRT_TO_BUS
 	select ARCH_HAVE_CUSTOM_GPIO_H
 	select GENERIC_FIND_FIRST_BIT
diff --git a/arch/unicore32/boot/compressed/Makefile b/arch/unicore32/boot/compressed/Makefile
index 9aecdd3ddc48..79ff908ad78c 100644
--- a/arch/unicore32/boot/compressed/Makefile
+++ b/arch/unicore32/boot/compressed/Makefile
@@ -22,9 +22,7 @@ $(obj)/font.c: $(srctree)/lib/fonts/font_8x8.c
 
 # piggy.S and piggy.o
 suffix_$(CONFIG_KERNEL_GZIP)	:= gzip
-suffix_$(CONFIG_KERNEL_BZIP2)	:= bz2
 suffix_$(CONFIG_KERNEL_LZO)	:= lzo
-suffix_$(CONFIG_KERNEL_LZMA)	:= lzma
 
 $(obj)/piggy.$(suffix_y): $(obj)/../Image FORCE
 	$(call if_changed,$(suffix_y))
@@ -39,7 +37,7 @@ targets		:= vmlinux vmlinux.lds font.o font.c head.o misc.o \
 			piggy.$(suffix_y) piggy.o piggy.S \
 
 # Make sure files are removed during clean
-extra-y		+= piggy.gzip piggy.bz2 piggy.lzo piggy.lzma
+extra-y		+= piggy.gzip piggy.lzo
 
 # ?
 LDFLAGS_vmlinux += -p
diff --git a/arch/unicore32/boot/compressed/misc.c b/arch/unicore32/boot/compressed/misc.c
index 5c65dfee278c..ab9b56cf6907 100644
--- a/arch/unicore32/boot/compressed/misc.c
+++ b/arch/unicore32/boot/compressed/misc.c
@@ -91,18 +91,10 @@ void error(char *x)
 #include "../../../../lib/decompress_inflate.c"
 #endif
 
-#ifdef CONFIG_KERNEL_BZIP2
-#include "../../../../lib/decompress_bunzip2.c"
-#endif
-
 #ifdef CONFIG_KERNEL_LZO
 #include "../../../../lib/decompress_unlzo.c"
 #endif
 
-#ifdef CONFIG_KERNEL_LZMA
-#include "../../../../lib/decompress_unlzma.c"
-#endif
-
 unsigned long decompress_kernel(unsigned long output_start,
 		unsigned long free_mem_ptr_p,
 		unsigned long free_mem_ptr_end_p)
-- 
2.19.1

[PATCH 10/17] arm: Remove support for LZMA compressed kernel

[Adam Borowski]

You want XZ instead: newer version of same algorithm, has an optimized
filter for arm32 executables, uses a library shared with other uses of XZ
in the kernel.

Signed-off-by: Adam Borowski <kilobyte@angband.pl>
---
 arch/arm/Kconfig                      | 1 -
 arch/arm/boot/compressed/Makefile     | 1 -
 arch/arm/boot/compressed/decompress.c | 4 ----
 3 files changed, 6 deletions(-)

diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 91be74d8df65..637e100de6e3 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -77,7 +77,6 @@ config ARM
 	select HAVE_IRQ_TIME_ACCOUNTING
 	select HAVE_KERNEL_GZIP
 	select HAVE_KERNEL_LZ4
-	select HAVE_KERNEL_LZMA
 	select HAVE_KERNEL_LZO
 	select HAVE_KERNEL_XZ
 	select HAVE_KPROBES if !XIP_KERNEL && !CPU_ENDIAN_BE32 && !CPU_V7M
diff --git a/arch/arm/boot/compressed/Makefile b/arch/arm/boot/compressed/Makefile
index 1f5a5ffe7fcf..37e6097b7506 100644
--- a/arch/arm/boot/compressed/Makefile
+++ b/arch/arm/boot/compressed/Makefile
@@ -72,7 +72,6 @@ CPPFLAGS_vmlinux.lds := -DTEXT_START="$(ZTEXTADDR)" -DBSS_START="$(ZBSSADDR)"
 
 compress-$(CONFIG_KERNEL_GZIP) = gzip
 compress-$(CONFIG_KERNEL_LZO)  = lzo
-compress-$(CONFIG_KERNEL_LZMA) = lzma
 compress-$(CONFIG_KERNEL_XZ)   = xzkern
 compress-$(CONFIG_KERNEL_LZ4)  = lz4
 
diff --git a/arch/arm/boot/compressed/decompress.c b/arch/arm/boot/compressed/decompress.c
index c16c1829a5e4..350e7a96f6af 100644
--- a/arch/arm/boot/compressed/decompress.c
+++ b/arch/arm/boot/compressed/decompress.c
@@ -41,10 +41,6 @@ extern int memcmp(const void *cs, const void *ct, size_t count);
 #include "../../../../lib/decompress_unlzo.c"
 #endif
 
-#ifdef CONFIG_KERNEL_LZMA
-#include "../../../../lib/decompress_unlzma.c"
-#endif
-
 #ifdef CONFIG_KERNEL_XZ
 #define memmove memmove
 #define memcpy memcpy
-- 
2.19.1

[PATCH 11/17] Kconfig: Remove support for BZIP2-compressed initrd and kernel

[Adam Borowski]

In no case it's a rational choice anymore: it's much slower than newer
algorithms at similar compression strength, and takes lots of memory
as well.

Removal of compression algorithms for vmlinuz is completely safe (the
kernel gets compressed by this very Makefile), less so for initrd as
someone might have requested it in initramfs.conf -- but it's not an
option users tend to alter, and they'd use a better algorithm anyway.
Thus, user damage is possible but on par with removal of an ancient
filesystem.

Signed-off-by: Adam Borowski <kilobyte@angband.pl>
---
 Makefile                   |  1 -
 init/Kconfig               | 17 ++---------------
 init/do_mounts_rd.c        |  1 -
 kernel/configs/tiny.config |  1 -
 usr/Kconfig                | 24 ------------------------
 5 files changed, 2 insertions(+), 42 deletions(-)

diff --git a/Makefile b/Makefile
index 9fce8b91c15f..c812467bfe11 100644
--- a/Makefile
+++ b/Makefile
@@ -938,7 +938,6 @@ export mod_compress_cmd
 # This shall be used by the dracut(8) tool while creating an initramfs image.
 #
 INITRD_COMPRESS-y                  := gzip
-INITRD_COMPRESS-$(CONFIG_RD_BZIP2) := bzip2
 INITRD_COMPRESS-$(CONFIG_RD_LZMA)  := lzma
 INITRD_COMPRESS-$(CONFIG_RD_XZ)    := xz
 INITRD_COMPRESS-$(CONFIG_RD_LZO)   := lzo
diff --git a/init/Kconfig b/init/Kconfig
index ffa5ae4abc88..412ba93673fa 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -119,9 +119,6 @@ config BUILD_SALT
 config HAVE_KERNEL_GZIP
 	bool
 
-config HAVE_KERNEL_BZIP2
-	bool
-
 config HAVE_KERNEL_LZMA
 	bool
 
@@ -143,7 +140,7 @@ config HAVE_KERNEL_UNCOMPRESSED
 choice
 	prompt "Kernel compression mode"
 	default KERNEL_GZIP
-	depends on HAVE_KERNEL_GZIP || HAVE_KERNEL_BZIP2 || HAVE_KERNEL_LZMA || HAVE_KERNEL_XZ || HAVE_KERNEL_LZO || HAVE_KERNEL_LZ4 || HAVE_KERNEL_ZSTD || HAVE_KERNEL_UNCOMPRESSED
+	depends on HAVE_KERNEL_GZIP || HAVE_KERNEL_LZMA || HAVE_KERNEL_XZ || HAVE_KERNEL_LZO || HAVE_KERNEL_LZ4 || HAVE_KERNEL_ZSTD || HAVE_KERNEL_UNCOMPRESSED
 	help
 	  The linux kernel is a kind of self-extracting executable.
 	  Several compression algorithms are available, which differ
@@ -151,7 +148,7 @@ choice
 	  Compression speed is only relevant when building a kernel.
 	  Decompression speed is relevant at each boot.
 
-	  If you have any problems with bzip2 or lzma compressed
+	  If you have any problems with lzma compressed
 	  kernels, mail me (Alain Knaff) <alain@knaff.lu>. (An older
 	  version of this functionality (bzip2 only), for 2.4, was
 	  supplied by Christian Ludwig)
@@ -169,16 +166,6 @@ config KERNEL_GZIP
 	  The old and tried gzip compression. It provides a good balance
 	  between compression ratio and decompression speed.
 
-config KERNEL_BZIP2
-	bool "Bzip2"
-	depends on HAVE_KERNEL_BZIP2
-	help
-	  Its compression ratio and speed is intermediate.
-	  Decompression speed is slowest among the choices.  The kernel
-	  size is about 10% smaller with bzip2, in comparison to gzip.
-	  Bzip2 uses a large amount of memory. For modern kernels you
-	  will need at least 8MB RAM or more for booting.
-
 config KERNEL_LZMA
 	bool "LZMA"
 	depends on HAVE_KERNEL_LZMA
diff --git a/init/do_mounts_rd.c b/init/do_mounts_rd.c
index 32fb049d18f9..5f26365ea8b1 100644
--- a/init/do_mounts_rd.c
+++ b/init/do_mounts_rd.c
@@ -48,7 +48,6 @@ static int __init crd_load(int in_fd, int out_fd, decompress_fn deco);
  *	cramfs
  *	squashfs
  *	gzip
- *	bzip2
  *	lzma
  *	xz
  *	lzo
diff --git a/kernel/configs/tiny.config b/kernel/configs/tiny.config
index 7fa0c4ae6394..c5480f87fae3 100644
--- a/kernel/configs/tiny.config
+++ b/kernel/configs/tiny.config
@@ -1,7 +1,6 @@
 # CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE is not set
 CONFIG_CC_OPTIMIZE_FOR_SIZE=y
 # CONFIG_KERNEL_GZIP is not set
-# CONFIG_KERNEL_BZIP2 is not set
 # CONFIG_KERNEL_LZMA is not set
 CONFIG_KERNEL_XZ=y
 # CONFIG_KERNEL_LZO is not set
diff --git a/usr/Kconfig b/usr/Kconfig
index 5ff529b75ee1..05b6be569041 100644
--- a/usr/Kconfig
+++ b/usr/Kconfig
@@ -61,15 +61,6 @@ config RD_GZIP
 	  Support loading of a gzip encoded initial ramdisk or cpio buffer.
 	  If unsure, say Y.
 
-config RD_BZIP2
-	bool "Support initial ramdisk/ramfs compressed using bzip2"
-	default y
-	depends on BLK_DEV_INITRD
-	select DECOMPRESS_BZIP2
-	help
-	  Support loading of a bzip2 encoded initial ramdisk or cpio buffer
-	  If unsure, say N.
-
 config RD_LZMA
 	bool "Support initial ramdisk/ramfs compressed using LZMA"
 	default y
@@ -161,19 +152,6 @@ config INITRAMFS_COMPRESSION_GZIP
 	  supported by your build system as the gzip tool is present by default
 	  on most distros.
 
-config INITRAMFS_COMPRESSION_BZIP2
-	bool "Bzip2"
-	depends on RD_BZIP2
-	help
-	  It's compression ratio and speed is intermediate. Decompression speed
-	  is slowest among the choices. The initramfs size is about 10% smaller
-	  with bzip2, in comparison to gzip. Bzip2 uses a large amount of
-	  memory. For modern kernels you will need at least 8MB RAM or more for
-	  booting.
-
-	  If you choose this, keep in mind that you need to have the bzip2 tool
-	  available to be able to compress the initram.
-
 config INITRAMFS_COMPRESSION_LZMA
 	bool "LZMA"
 	depends on RD_LZMA
@@ -241,7 +219,6 @@ config INITRAMFS_COMPRESSION
 	string
 	default ""      if INITRAMFS_COMPRESSION_NONE
 	default ".gz"   if INITRAMFS_COMPRESSION_GZIP
-	default ".bz2"  if INITRAMFS_COMPRESSION_BZIP2
 	default ".lzma" if INITRAMFS_COMPRESSION_LZMA
 	default ".xz"   if INITRAMFS_COMPRESSION_XZ
 	default ".lzo"  if INITRAMFS_COMPRESSION_LZO
@@ -252,6 +229,5 @@ config INITRAMFS_COMPRESSION
 	default ".lzo"  if RD_LZO
 	default ".xz"   if RD_XZ
 	default ".lzma" if RD_LZMA
-	default ".bz2"  if RD_BZIP2
 	default ".zst"  if RD_ZSTD
 	default ""
-- 
2.19.1

[PATCH 12/17] Kconfig: Remove support for LZMA-compressed initrd

[Adam Borowski]

Obsoleted by XZ.

The config option for compressing the kernel stays, as some archs have a
bootloader outside the kernel that wants LZMA.

Signed-off-by: Adam Borowski <kilobyte@angband.pl>
---
 Makefile    |  1 -
 usr/Kconfig | 28 ++--------------------------
 2 files changed, 2 insertions(+), 27 deletions(-)

diff --git a/Makefile b/Makefile
index c812467bfe11..97e4bf26a6d3 100644
--- a/Makefile
+++ b/Makefile
@@ -938,7 +938,6 @@ export mod_compress_cmd
 # This shall be used by the dracut(8) tool while creating an initramfs image.
 #
 INITRD_COMPRESS-y                  := gzip
-INITRD_COMPRESS-$(CONFIG_RD_LZMA)  := lzma
 INITRD_COMPRESS-$(CONFIG_RD_XZ)    := xz
 INITRD_COMPRESS-$(CONFIG_RD_LZO)   := lzo
 INITRD_COMPRESS-$(CONFIG_RD_LZ4)   := lz4
diff --git a/usr/Kconfig b/usr/Kconfig
index 05b6be569041..8d99edacabc9 100644
--- a/usr/Kconfig
+++ b/usr/Kconfig
@@ -61,15 +61,6 @@ config RD_GZIP
 	  Support loading of a gzip encoded initial ramdisk or cpio buffer.
 	  If unsure, say Y.
 
-config RD_LZMA
-	bool "Support initial ramdisk/ramfs compressed using LZMA"
-	default y
-	depends on BLK_DEV_INITRD
-	select DECOMPRESS_LZMA
-	help
-	  Support loading of a LZMA encoded initial ramdisk or cpio buffer
-	  If unsure, say N.
-
 config RD_XZ
 	bool "Support initial ramdisk/ramfs compressed using XZ"
 	depends on BLK_DEV_INITRD
@@ -118,8 +109,8 @@ choice
 	  when building a kernel.  Decompression speed is relevant at
 	  each boot. Also the memory usage during decompression may become
 	  relevant on memory constrained systems. This is usually based on the
-	  dictionary size of the algorithm with algorithms like XZ and LZMA
-	  featuring large dictionary sizes.
+	  dictionary size of the algorithm with algorithms like XZ featuring
+	  large dictionary sizes.
 
 	  High compression options are mostly useful for users who are
 	  low on RAM, since it reduces the memory consumption during
@@ -152,19 +143,6 @@ config INITRAMFS_COMPRESSION_GZIP
 	  supported by your build system as the gzip tool is present by default
 	  on most distros.
 
-config INITRAMFS_COMPRESSION_LZMA
-	bool "LZMA"
-	depends on RD_LZMA
-	help
-	  This algorithm's compression ratio is best but has a large dictionary
-	  size which might cause issues in memory constrained systems.
-	  Decompression speed is between the other choices. Compression is
-	  slowest. The initramfs size is about 33% smaller with LZMA in
-	  comparison to gzip.
-
-	  If you choose this, keep in mind that you may need to install the xz
-	  or lzma tools to be able to compress the initram.
-
 config INITRAMFS_COMPRESSION_XZ
 	bool "XZ"
 	depends on RD_XZ
@@ -219,7 +197,6 @@ config INITRAMFS_COMPRESSION
 	string
 	default ""      if INITRAMFS_COMPRESSION_NONE
 	default ".gz"   if INITRAMFS_COMPRESSION_GZIP
-	default ".lzma" if INITRAMFS_COMPRESSION_LZMA
 	default ".xz"   if INITRAMFS_COMPRESSION_XZ
 	default ".lzo"  if INITRAMFS_COMPRESSION_LZO
 	default ".lz4"  if INITRAMFS_COMPRESSION_LZ4
@@ -228,6 +205,5 @@ config INITRAMFS_COMPRESSION
 	default ".lz4"  if RD_LZ4
 	default ".lzo"  if RD_LZO
 	default ".xz"   if RD_XZ
-	default ".lzma" if RD_LZMA
 	default ".zst"  if RD_ZSTD
 	default ""
-- 
2.19.1

[PATCH 13/17] arch/*: Purge references to CONFIG_RD_BZIP2/LZMA from various defconfigs

[Adam Borowski]

They don't exist anymore.

Signed-off-by: Adam Borowski <kilobyte@angband.pl>
---
 arch/arm/configs/aspeed_g4_defconfig       | 1 -
 arch/arm/configs/aspeed_g5_defconfig       | 1 -
 arch/arm/configs/clps711x_defconfig        | 1 -
 arch/arm/configs/ezx_defconfig             | 2 --
 arch/arm/configs/hisi_defconfig            | 1 -
 arch/arm/configs/imote2_defconfig          | 2 --
 arch/arm/configs/lpc18xx_defconfig         | 2 --
 arch/arm/configs/vf610m4_defconfig         | 2 --
 arch/m68k/configs/stmark2_defconfig        | 2 --
 arch/mips/configs/ar7_defconfig            | 1 -
 arch/mips/configs/ath25_defconfig          | 1 -
 arch/mips/configs/ath79_defconfig          | 1 -
 arch/mips/configs/lemote2f_defconfig       | 2 --
 arch/mips/configs/loongson3_defconfig      | 2 --
 arch/mips/configs/nlm_xlp_defconfig        | 2 --
 arch/mips/configs/nlm_xlr_defconfig        | 2 --
 arch/mips/configs/pistachio_defconfig      | 2 --
 arch/openrisc/configs/simple_smp_defconfig | 2 --
 arch/powerpc/configs/44x/fsp2_defconfig    | 1 -
 arch/powerpc/configs/skiroot_defconfig     | 2 --
 arch/sh/configs/sdk7786_defconfig          | 2 --
 arch/xtensa/configs/cadence_csp_defconfig  | 2 --
 arch/xtensa/configs/nommu_kc705_defconfig  | 2 --
 23 files changed, 38 deletions(-)

diff --git a/arch/arm/configs/aspeed_g4_defconfig b/arch/arm/configs/aspeed_g4_defconfig
index 1446262921b4..2e978ba5fab3 100644
--- a/arch/arm/configs/aspeed_g4_defconfig
+++ b/arch/arm/configs/aspeed_g4_defconfig
@@ -8,7 +8,6 @@ CONFIG_IKCONFIG_PROC=y
 CONFIG_LOG_BUF_SHIFT=16
 CONFIG_CGROUPS=y
 CONFIG_BLK_DEV_INITRD=y
-# CONFIG_RD_BZIP2 is not set
 # CONFIG_RD_LZO is not set
 # CONFIG_RD_LZ4 is not set
 # CONFIG_UID16 is not set
diff --git a/arch/arm/configs/aspeed_g5_defconfig b/arch/arm/configs/aspeed_g5_defconfig
index 02fa3a41add5..4fef8a5d208a 100644
--- a/arch/arm/configs/aspeed_g5_defconfig
+++ b/arch/arm/configs/aspeed_g5_defconfig
@@ -8,7 +8,6 @@ CONFIG_IKCONFIG_PROC=y
 CONFIG_LOG_BUF_SHIFT=16
 CONFIG_CGROUPS=y
 CONFIG_BLK_DEV_INITRD=y
-# CONFIG_RD_BZIP2 is not set
 # CONFIG_RD_LZO is not set
 # CONFIG_RD_LZ4 is not set
 # CONFIG_UID16 is not set
diff --git a/arch/arm/configs/clps711x_defconfig b/arch/arm/configs/clps711x_defconfig
index fc105c9178cc..63e029d9c5a6 100644
--- a/arch/arm/configs/clps711x_defconfig
+++ b/arch/arm/configs/clps711x_defconfig
@@ -2,7 +2,6 @@ CONFIG_KERNEL_LZMA=y
 CONFIG_SYSVIPC=y
 CONFIG_LOG_BUF_SHIFT=14
 CONFIG_BLK_DEV_INITRD=y
-CONFIG_RD_LZMA=y
 CONFIG_EMBEDDED=y
 CONFIG_SLOB=y
 CONFIG_JUMP_LABEL=y
diff --git a/arch/arm/configs/ezx_defconfig b/arch/arm/configs/ezx_defconfig
index 484e51fbd4a6..47bbd7b20f07 100644
--- a/arch/arm/configs/ezx_defconfig
+++ b/arch/arm/configs/ezx_defconfig
@@ -4,8 +4,6 @@ CONFIG_SYSVIPC=y
 CONFIG_LOG_BUF_SHIFT=14
 CONFIG_SYSFS_DEPRECATED_V2=y
 CONFIG_BLK_DEV_INITRD=y
-CONFIG_RD_BZIP2=y
-CONFIG_RD_LZMA=y
 CONFIG_EXPERT=y
 # CONFIG_COMPAT_BRK is not set
 CONFIG_SLAB=y
diff --git a/arch/arm/configs/hisi_defconfig b/arch/arm/configs/hisi_defconfig
index 74d611e41e02..c8660e175f15 100644
--- a/arch/arm/configs/hisi_defconfig
+++ b/arch/arm/configs/hisi_defconfig
@@ -1,7 +1,6 @@
 CONFIG_NO_HZ=y
 CONFIG_HIGH_RES_TIMERS=y
 CONFIG_BLK_DEV_INITRD=y
-CONFIG_RD_LZMA=y
 CONFIG_ARCH_HISI=y
 CONFIG_ARCH_HI3xxx=y
 CONFIG_PARTITION_ADVANCED=y
diff --git a/arch/arm/configs/imote2_defconfig b/arch/arm/configs/imote2_defconfig
index f204017c26b9..5cd017270f1e 100644
--- a/arch/arm/configs/imote2_defconfig
+++ b/arch/arm/configs/imote2_defconfig
@@ -3,8 +3,6 @@ CONFIG_SYSVIPC=y
 CONFIG_LOG_BUF_SHIFT=14
 CONFIG_SYSFS_DEPRECATED_V2=y
 CONFIG_BLK_DEV_INITRD=y
-CONFIG_RD_BZIP2=y
-CONFIG_RD_LZMA=y
 CONFIG_EXPERT=y
 # CONFIG_COMPAT_BRK is not set
 CONFIG_SLAB=y
diff --git a/arch/arm/configs/lpc18xx_defconfig b/arch/arm/configs/lpc18xx_defconfig
index 23df2518203d..f0d36814111a 100644
--- a/arch/arm/configs/lpc18xx_defconfig
+++ b/arch/arm/configs/lpc18xx_defconfig
@@ -1,8 +1,6 @@
 CONFIG_CROSS_COMPILE="arm-linux-gnueabihf-"
 CONFIG_HIGH_RES_TIMERS=y
 CONFIG_BLK_DEV_INITRD=y
-# CONFIG_RD_BZIP2 is not set
-# CONFIG_RD_LZMA is not set
 # CONFIG_RD_XZ is not set
 # CONFIG_RD_LZO is not set
 # CONFIG_RD_LZ4 is not set
diff --git a/arch/arm/configs/vf610m4_defconfig b/arch/arm/configs/vf610m4_defconfig
index a89f035c3b01..6b34e135035b 100644
--- a/arch/arm/configs/vf610m4_defconfig
+++ b/arch/arm/configs/vf610m4_defconfig
@@ -1,7 +1,5 @@
 CONFIG_NAMESPACES=y
 CONFIG_BLK_DEV_INITRD=y
-# CONFIG_RD_BZIP2 is not set
-# CONFIG_RD_LZMA is not set
 # CONFIG_RD_XZ is not set
 # CONFIG_RD_LZ4 is not set
 CONFIG_KALLSYMS_ALL=y
diff --git a/arch/m68k/configs/stmark2_defconfig b/arch/m68k/configs/stmark2_defconfig
index 3d07b1de7eb0..fe82d37ba81d 100644
--- a/arch/m68k/configs/stmark2_defconfig
+++ b/arch/m68k/configs/stmark2_defconfig
@@ -5,8 +5,6 @@ CONFIG_SYSVIPC=y
 CONFIG_LOG_BUF_SHIFT=14
 CONFIG_NAMESPACES=y
 CONFIG_BLK_DEV_INITRD=y
-# CONFIG_RD_BZIP2 is not set
-# CONFIG_RD_LZMA is not set
 # CONFIG_RD_XZ is not set
 # CONFIG_RD_LZO is not set
 # CONFIG_RD_LZ4 is not set
diff --git a/arch/mips/configs/ar7_defconfig b/arch/mips/configs/ar7_defconfig
index 5651f4d8f45c..a0ce69fb4fcb 100644
--- a/arch/mips/configs/ar7_defconfig
+++ b/arch/mips/configs/ar7_defconfig
@@ -12,7 +12,6 @@ CONFIG_LOG_BUF_SHIFT=14
 CONFIG_SYSFS_DEPRECATED_V2=y
 CONFIG_RELAY=y
 CONFIG_BLK_DEV_INITRD=y
-CONFIG_RD_LZMA=y
 CONFIG_EXPERT=y
 # CONFIG_KALLSYMS is not set
 # CONFIG_ELF_CORE is not set
diff --git a/arch/mips/configs/ath25_defconfig b/arch/mips/configs/ath25_defconfig
index b8d48038e74f..1a83f91dad42 100644
--- a/arch/mips/configs/ath25_defconfig
+++ b/arch/mips/configs/ath25_defconfig
@@ -9,7 +9,6 @@ CONFIG_SYSVIPC=y
 CONFIG_HIGH_RES_TIMERS=y
 CONFIG_BLK_DEV_INITRD=y
 # CONFIG_RD_GZIP is not set
-# CONFIG_RD_BZIP2 is not set
 # CONFIG_RD_XZ is not set
 # CONFIG_RD_LZO is not set
 # CONFIG_RD_LZ4 is not set
diff --git a/arch/mips/configs/ath79_defconfig b/arch/mips/configs/ath79_defconfig
index 951c4231bdb8..c11f1870ed6f 100644
--- a/arch/mips/configs/ath79_defconfig
+++ b/arch/mips/configs/ath79_defconfig
@@ -12,7 +12,6 @@ CONFIG_SYSVIPC=y
 CONFIG_HIGH_RES_TIMERS=y
 CONFIG_BLK_DEV_INITRD=y
 # CONFIG_RD_GZIP is not set
-CONFIG_RD_LZMA=y
 # CONFIG_KALLSYMS is not set
 # CONFIG_AIO is not set
 CONFIG_EMBEDDED=y
diff --git a/arch/mips/configs/lemote2f_defconfig b/arch/mips/configs/lemote2f_defconfig
index 02be95c1b712..2e2561f1aec3 100644
--- a/arch/mips/configs/lemote2f_defconfig
+++ b/arch/mips/configs/lemote2f_defconfig
@@ -17,8 +17,6 @@ CONFIG_IKCONFIG_PROC=y
 CONFIG_LOG_BUF_SHIFT=15
 CONFIG_SYSFS_DEPRECATED_V2=y
 CONFIG_BLK_DEV_INITRD=y
-CONFIG_RD_BZIP2=y
-CONFIG_RD_LZMA=y
 # CONFIG_CC_OPTIMIZE_FOR_SIZE is not set
 CONFIG_EXPERT=y
 CONFIG_PROFILING=y
diff --git a/arch/mips/configs/loongson3_defconfig b/arch/mips/configs/loongson3_defconfig
index 324dfee23dfb..42eae3436bb4 100644
--- a/arch/mips/configs/loongson3_defconfig
+++ b/arch/mips/configs/loongson3_defconfig
@@ -32,8 +32,6 @@ CONFIG_SCHED_AUTOGROUP=y
 CONFIG_SYSFS_DEPRECATED=y
 CONFIG_RELAY=y
 CONFIG_BLK_DEV_INITRD=y
-CONFIG_RD_BZIP2=y
-CONFIG_RD_LZMA=y
 CONFIG_SYSCTL_SYSCALL=y
 CONFIG_EMBEDDED=y
 CONFIG_MODULES=y
diff --git a/arch/mips/configs/nlm_xlp_defconfig b/arch/mips/configs/nlm_xlp_defconfig
index e8e1dd8e0e99..16e44d0f1d29 100644
--- a/arch/mips/configs/nlm_xlp_defconfig
+++ b/arch/mips/configs/nlm_xlp_defconfig
@@ -21,8 +21,6 @@ CONFIG_HIGH_RES_TIMERS=y
 CONFIG_CGROUPS=y
 CONFIG_NAMESPACES=y
 CONFIG_BLK_DEV_INITRD=y
-CONFIG_RD_BZIP2=y
-CONFIG_RD_LZMA=y
 CONFIG_KALLSYMS_ALL=y
 CONFIG_EMBEDDED=y
 # CONFIG_COMPAT_BRK is not set
diff --git a/arch/mips/configs/nlm_xlr_defconfig b/arch/mips/configs/nlm_xlr_defconfig
index c4477a4d40c1..9340f42184f7 100644
--- a/arch/mips/configs/nlm_xlr_defconfig
+++ b/arch/mips/configs/nlm_xlr_defconfig
@@ -22,8 +22,6 @@ CONFIG_NAMESPACES=y
 CONFIG_SCHED_AUTOGROUP=y
 CONFIG_BLK_DEV_INITRD=y
 CONFIG_INITRAMFS_SOURCE=""
-CONFIG_RD_BZIP2=y
-CONFIG_RD_LZMA=y
 CONFIG_INITRAMFS_COMPRESSION_GZIP=y
 CONFIG_EXPERT=y
 CONFIG_KALLSYMS_ALL=y
diff --git a/arch/mips/configs/pistachio_defconfig b/arch/mips/configs/pistachio_defconfig
index b22a3cf149b6..4257f90d1272 100644
--- a/arch/mips/configs/pistachio_defconfig
+++ b/arch/mips/configs/pistachio_defconfig
@@ -21,8 +21,6 @@ CONFIG_CFS_BANDWIDTH=y
 CONFIG_NAMESPACES=y
 CONFIG_USER_NS=y
 CONFIG_BLK_DEV_INITRD=y
-# CONFIG_RD_BZIP2 is not set
-# CONFIG_RD_LZMA is not set
 # CONFIG_RD_LZO is not set
 # CONFIG_RD_LZ4 is not set
 CONFIG_CC_OPTIMIZE_FOR_SIZE=y
diff --git a/arch/openrisc/configs/simple_smp_defconfig b/arch/openrisc/configs/simple_smp_defconfig
index b6e3c7e158e7..03b7633a9a2b 100644
--- a/arch/openrisc/configs/simple_smp_defconfig
+++ b/arch/openrisc/configs/simple_smp_defconfig
@@ -4,8 +4,6 @@ CONFIG_NO_HZ=y
 CONFIG_LOG_BUF_SHIFT=14
 CONFIG_BLK_DEV_INITRD=y
 # CONFIG_RD_GZIP is not set
-# CONFIG_RD_BZIP2 is not set
-# CONFIG_RD_LZMA is not set
 # CONFIG_RD_XZ is not set
 # CONFIG_RD_LZO is not set
 # CONFIG_RD_LZ4 is not set
diff --git a/arch/powerpc/configs/44x/fsp2_defconfig b/arch/powerpc/configs/44x/fsp2_defconfig
index bae6b26bcfba..8ccae1052efb 100644
--- a/arch/powerpc/configs/44x/fsp2_defconfig
+++ b/arch/powerpc/configs/44x/fsp2_defconfig
@@ -9,7 +9,6 @@ CONFIG_IKCONFIG=y
 CONFIG_IKCONFIG_PROC=y
 CONFIG_LOG_BUF_SHIFT=16
 CONFIG_BLK_DEV_INITRD=y
-# CONFIG_RD_LZMA is not set
 # CONFIG_RD_XZ is not set
 # CONFIG_RD_LZO is not set
 # CONFIG_RD_LZ4 is not set
diff --git a/arch/powerpc/configs/skiroot_defconfig b/arch/powerpc/configs/skiroot_defconfig
index cfdd08897a06..5d790a65e733 100644
--- a/arch/powerpc/configs/skiroot_defconfig
+++ b/arch/powerpc/configs/skiroot_defconfig
@@ -16,8 +16,6 @@ CONFIG_IKCONFIG_PROC=y
 CONFIG_LOG_BUF_SHIFT=20
 CONFIG_BLK_DEV_INITRD=y
 # CONFIG_RD_GZIP is not set
-# CONFIG_RD_BZIP2 is not set
-# CONFIG_RD_LZMA is not set
 # CONFIG_RD_LZO is not set
 # CONFIG_RD_LZ4 is not set
 CONFIG_CC_OPTIMIZE_FOR_SIZE=y
diff --git a/arch/sh/configs/sdk7786_defconfig b/arch/sh/configs/sdk7786_defconfig
index e9ee0c878ead..4e71a98bc814 100644
--- a/arch/sh/configs/sdk7786_defconfig
+++ b/arch/sh/configs/sdk7786_defconfig
@@ -29,8 +29,6 @@ CONFIG_USER_NS=y
 CONFIG_PID_NS=y
 CONFIG_NET_NS=y
 CONFIG_BLK_DEV_INITRD=y
-CONFIG_RD_BZIP2=y
-CONFIG_RD_LZMA=y
 CONFIG_RD_LZO=y
 # CONFIG_COMPAT_BRK is not set
 CONFIG_SLAB=y
diff --git a/arch/xtensa/configs/cadence_csp_defconfig b/arch/xtensa/configs/cadence_csp_defconfig
index 3221b7053fa3..e7b295ec6acd 100644
--- a/arch/xtensa/configs/cadence_csp_defconfig
+++ b/arch/xtensa/configs/cadence_csp_defconfig
@@ -15,8 +15,6 @@ CONFIG_SCHED_AUTOGROUP=y
 CONFIG_RELAY=y
 CONFIG_BLK_DEV_INITRD=y
 CONFIG_INITRAMFS_SOURCE="$$KERNEL_INITRAMFS_SOURCE"
-# CONFIG_RD_BZIP2 is not set
-# CONFIG_RD_LZMA is not set
 # CONFIG_RD_XZ is not set
 # CONFIG_RD_LZO is not set
 # CONFIG_RD_LZ4 is not set
diff --git a/arch/xtensa/configs/nommu_kc705_defconfig b/arch/xtensa/configs/nommu_kc705_defconfig
index f3fc4f970ca8..9a449d13eb1e 100644
--- a/arch/xtensa/configs/nommu_kc705_defconfig
+++ b/arch/xtensa/configs/nommu_kc705_defconfig
@@ -15,8 +15,6 @@ CONFIG_NAMESPACES=y
 CONFIG_SCHED_AUTOGROUP=y
 CONFIG_RELAY=y
 CONFIG_BLK_DEV_INITRD=y
-# CONFIG_RD_BZIP2 is not set
-# CONFIG_RD_LZMA is not set
 # CONFIG_RD_XZ is not set
 # CONFIG_RD_LZO is not set
 # CONFIG_RD_LZ4 is not set
-- 
2.19.1

[PATCH 14/17] lib: Completely purge now-unused bzip2 code from the kernel

[Adam Borowski]

All remaining references are userspace code to build tarballs, packages
or such.

Signed-off-by: Adam Borowski <kilobyte@angband.pl>
---
 lib/Kconfig              |   3 -
 lib/Makefile             |   1 -
 lib/decompress.c         |   4 -
 lib/decompress_bunzip2.c | 756 ---------------------------------------
 scripts/Makefile.lib     |  12 +-
 5 files changed, 2 insertions(+), 774 deletions(-)
 delete mode 100644 lib/decompress_bunzip2.c

diff --git a/lib/Kconfig b/lib/Kconfig
index e7ab43fd5461..83a548b8c504 100644
--- a/lib/Kconfig
+++ b/lib/Kconfig
@@ -286,9 +286,6 @@ config DECOMPRESS_GZIP
 	select ZLIB_INFLATE
 	tristate
 
-config DECOMPRESS_BZIP2
-	tristate
-
 config DECOMPRESS_LZMA
 	tristate
 
diff --git a/lib/Makefile b/lib/Makefile
index 58b48993f48a..4c1905e6d3a7 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -134,7 +134,6 @@ obj-$(CONFIG_XZ_DEC) += xz/
 obj-$(CONFIG_RAID6_PQ) += raid6/
 
 lib-$(CONFIG_DECOMPRESS_GZIP) += decompress_inflate.o
-lib-$(CONFIG_DECOMPRESS_BZIP2) += decompress_bunzip2.o
 lib-$(CONFIG_DECOMPRESS_LZMA) += decompress_unlzma.o
 lib-$(CONFIG_DECOMPRESS_XZ) += decompress_unxz.o
 lib-$(CONFIG_DECOMPRESS_LZO) += decompress_unlzo.o
diff --git a/lib/decompress.c b/lib/decompress.c
index ab3fc90ffc64..60f05122b9da 100644
--- a/lib/decompress.c
+++ b/lib/decompress.c
@@ -23,9 +23,6 @@
 #ifndef CONFIG_DECOMPRESS_GZIP
 # define gunzip NULL
 #endif
-#ifndef CONFIG_DECOMPRESS_BZIP2
-# define bunzip2 NULL
-#endif
 #ifndef CONFIG_DECOMPRESS_LZMA
 # define unlzma NULL
 #endif
@@ -51,7 +48,6 @@ struct compress_format {
 static const struct compress_format compressed_formats[] __initconst = {
 	{ {0x1f, 0x8b}, "gzip", gunzip },
 	{ {0x1f, 0x9e}, "gzip", gunzip },
-	{ {0x42, 0x5a}, "bzip2", bunzip2 },
 	{ {0x5d, 0x00}, "lzma", unlzma },
 	{ {0xfd, 0x37}, "xz", unxz },
 	{ {0x89, 0x4c}, "lzo", unlzo },
diff --git a/lib/decompress_bunzip2.c b/lib/decompress_bunzip2.c
deleted file mode 100644
index 7c4932eed748..000000000000
--- a/lib/decompress_bunzip2.c
+++ /dev/null
@@ -1,756 +0,0 @@
-/*	Small bzip2 deflate implementation, by Rob Landley (rob@landley.net).
-
-	Based on bzip2 decompression code by Julian R Seward (jseward@acm.org),
-	which also acknowledges contributions by Mike Burrows, David Wheeler,
-	Peter Fenwick, Alistair Moffat, Radford Neal, Ian H. Witten,
-	Robert Sedgewick, and Jon L. Bentley.
-
-	This code is licensed under the LGPLv2:
-		LGPL (http://www.gnu.org/copyleft/lgpl.html
-*/
-
-/*
-	Size and speed optimizations by Manuel Novoa III  (mjn3@codepoet.org).
-
-	More efficient reading of Huffman codes, a streamlined read_bunzip()
-	function, and various other tweaks.  In (limited) tests, approximately
-	20% faster than bzcat on x86 and about 10% faster on arm.
-
-	Note that about 2/3 of the time is spent in read_unzip() reversing
-	the Burrows-Wheeler transformation.  Much of that time is delay
-	resulting from cache misses.
-
-	I would ask that anyone benefiting from this work, especially those
-	using it in commercial products, consider making a donation to my local
-	non-profit hospice organization in the name of the woman I loved, who
-	passed away Feb. 12, 2003.
-
-		In memory of Toni W. Hagan
-
-		Hospice of Acadiana, Inc.
-		2600 Johnston St., Suite 200
-		Lafayette, LA 70503-3240
-
-		Phone (337) 232-1234 or 1-800-738-2226
-		Fax   (337) 232-1297
-
-		http://www.hospiceacadiana.com/
-
-	Manuel
- */
-
-/*
-	Made it fit for running in Linux Kernel by Alain Knaff (alain@knaff.lu)
-*/
-
-
-#ifdef STATIC
-#define PREBOOT
-#else
-#include <linux/decompress/bunzip2.h>
-#endif /* STATIC */
-
-#include <linux/decompress/mm.h>
-#include <linux/crc32poly.h>
-
-#ifndef INT_MAX
-#define INT_MAX 0x7fffffff
-#endif
-
-/* Constants for Huffman coding */
-#define MAX_GROUPS		6
-#define GROUP_SIZE   		50	/* 64 would have been more efficient */
-#define MAX_HUFCODE_BITS 	20	/* Longest Huffman code allowed */
-#define MAX_SYMBOLS 		258	/* 256 literals + RUNA + RUNB */
-#define SYMBOL_RUNA		0
-#define SYMBOL_RUNB		1
-
-/* Status return values */
-#define RETVAL_OK			0
-#define RETVAL_LAST_BLOCK		(-1)
-#define RETVAL_NOT_BZIP_DATA		(-2)
-#define RETVAL_UNEXPECTED_INPUT_EOF	(-3)
-#define RETVAL_UNEXPECTED_OUTPUT_EOF	(-4)
-#define RETVAL_DATA_ERROR		(-5)
-#define RETVAL_OUT_OF_MEMORY		(-6)
-#define RETVAL_OBSOLETE_INPUT		(-7)
-
-/* Other housekeeping constants */
-#define BZIP2_IOBUF_SIZE		4096
-
-/* This is what we know about each Huffman coding group */
-struct group_data {
-	/* We have an extra slot at the end of limit[] for a sentinal value. */
-	int limit[MAX_HUFCODE_BITS+1];
-	int base[MAX_HUFCODE_BITS];
-	int permute[MAX_SYMBOLS];
-	int minLen, maxLen;
-};
-
-/* Structure holding all the housekeeping data, including IO buffers and
-   memory that persists between calls to bunzip */
-struct bunzip_data {
-	/* State for interrupting output loop */
-	int writeCopies, writePos, writeRunCountdown, writeCount, writeCurrent;
-	/* I/O tracking data (file handles, buffers, positions, etc.) */
-	long (*fill)(void*, unsigned long);
-	long inbufCount, inbufPos /*, outbufPos*/;
-	unsigned char *inbuf /*,*outbuf*/;
-	unsigned int inbufBitCount, inbufBits;
-	/* The CRC values stored in the block header and calculated from the
-	data */
-	unsigned int crc32Table[256], headerCRC, totalCRC, writeCRC;
-	/* Intermediate buffer and its size (in bytes) */
-	unsigned int *dbuf, dbufSize;
-	/* These things are a bit too big to go on the stack */
-	unsigned char selectors[32768];		/* nSelectors = 15 bits */
-	struct group_data groups[MAX_GROUPS];	/* Huffman coding tables */
-	int io_error;			/* non-zero if we have IO error */
-	int byteCount[256];
-	unsigned char symToByte[256], mtfSymbol[256];
-};
-
-
-/* Return the next nnn bits of input.  All reads from the compressed input
-   are done through this function.  All reads are big endian */
-static unsigned int INIT get_bits(struct bunzip_data *bd, char bits_wanted)
-{
-	unsigned int bits = 0;
-
-	/* If we need to get more data from the byte buffer, do so.
-	   (Loop getting one byte at a time to enforce endianness and avoid
-	   unaligned access.) */
-	while (bd->inbufBitCount < bits_wanted) {
-		/* If we need to read more data from file into byte buffer, do
-		   so */
-		if (bd->inbufPos == bd->inbufCount) {
-			if (bd->io_error)
-				return 0;
-			bd->inbufCount = bd->fill(bd->inbuf, BZIP2_IOBUF_SIZE);
-			if (bd->inbufCount <= 0) {
-				bd->io_error = RETVAL_UNEXPECTED_INPUT_EOF;
-				return 0;
-			}
-			bd->inbufPos = 0;
-		}
-		/* Avoid 32-bit overflow (dump bit buffer to top of output) */
-		if (bd->inbufBitCount >= 24) {
-			bits = bd->inbufBits&((1 << bd->inbufBitCount)-1);
-			bits_wanted -= bd->inbufBitCount;
-			bits <<= bits_wanted;
-			bd->inbufBitCount = 0;
-		}
-		/* Grab next 8 bits of input from buffer. */
-		bd->inbufBits = (bd->inbufBits << 8)|bd->inbuf[bd->inbufPos++];
-		bd->inbufBitCount += 8;
-	}
-	/* Calculate result */
-	bd->inbufBitCount -= bits_wanted;
-	bits |= (bd->inbufBits >> bd->inbufBitCount)&((1 << bits_wanted)-1);
-
-	return bits;
-}
-
-/* Unpacks the next block and sets up for the inverse burrows-wheeler step. */
-
-static int INIT get_next_block(struct bunzip_data *bd)
-{
-	struct group_data *hufGroup = NULL;
-	int *base = NULL;
-	int *limit = NULL;
-	int dbufCount, nextSym, dbufSize, groupCount, selector,
-		i, j, k, t, runPos, symCount, symTotal, nSelectors, *byteCount;
-	unsigned char uc, *symToByte, *mtfSymbol, *selectors;
-	unsigned int *dbuf, origPtr;
-
-	dbuf = bd->dbuf;
-	dbufSize = bd->dbufSize;
-	selectors = bd->selectors;
-	byteCount = bd->byteCount;
-	symToByte = bd->symToByte;
-	mtfSymbol = bd->mtfSymbol;
-
-	/* Read in header signature and CRC, then validate signature.
-	   (last block signature means CRC is for whole file, return now) */
-	i = get_bits(bd, 24);
-	j = get_bits(bd, 24);
-	bd->headerCRC = get_bits(bd, 32);
-	if ((i == 0x177245) && (j == 0x385090))
-		return RETVAL_LAST_BLOCK;
-	if ((i != 0x314159) || (j != 0x265359))
-		return RETVAL_NOT_BZIP_DATA;
-	/* We can add support for blockRandomised if anybody complains.
-	   There was some code for this in busybox 1.0.0-pre3, but nobody ever
-	   noticed that it didn't actually work. */
-	if (get_bits(bd, 1))
-		return RETVAL_OBSOLETE_INPUT;
-	origPtr = get_bits(bd, 24);
-	if (origPtr >= dbufSize)
-		return RETVAL_DATA_ERROR;
-	/* mapping table: if some byte values are never used (encoding things
-	   like ascii text), the compression code removes the gaps to have fewer
-	   symbols to deal with, and writes a sparse bitfield indicating which
-	   values were present.  We make a translation table to convert the
-	   symbols back to the corresponding bytes. */
-	t = get_bits(bd, 16);
-	symTotal = 0;
-	for (i = 0; i < 16; i++) {
-		if (t&(1 << (15-i))) {
-			k = get_bits(bd, 16);
-			for (j = 0; j < 16; j++)
-				if (k&(1 << (15-j)))
-					symToByte[symTotal++] = (16*i)+j;
-		}
-	}
-	/* How many different Huffman coding groups does this block use? */
-	groupCount = get_bits(bd, 3);
-	if (groupCount < 2 || groupCount > MAX_GROUPS)
-		return RETVAL_DATA_ERROR;
-	/* nSelectors: Every GROUP_SIZE many symbols we select a new
-	   Huffman coding group.  Read in the group selector list,
-	   which is stored as MTF encoded bit runs.  (MTF = Move To
-	   Front, as each value is used it's moved to the start of the
-	   list.) */
-	nSelectors = get_bits(bd, 15);
-	if (!nSelectors)
-		return RETVAL_DATA_ERROR;
-	for (i = 0; i < groupCount; i++)
-		mtfSymbol[i] = i;
-	for (i = 0; i < nSelectors; i++) {
-		/* Get next value */
-		for (j = 0; get_bits(bd, 1); j++)
-			if (j >= groupCount)
-				return RETVAL_DATA_ERROR;
-		/* Decode MTF to get the next selector */
-		uc = mtfSymbol[j];
-		for (; j; j--)
-			mtfSymbol[j] = mtfSymbol[j-1];
-		mtfSymbol[0] = selectors[i] = uc;
-	}
-	/* Read the Huffman coding tables for each group, which code
-	   for symTotal literal symbols, plus two run symbols (RUNA,
-	   RUNB) */
-	symCount = symTotal+2;
-	for (j = 0; j < groupCount; j++) {
-		unsigned char length[MAX_SYMBOLS], temp[MAX_HUFCODE_BITS+1];
-		int	minLen,	maxLen, pp;
-		/* Read Huffman code lengths for each symbol.  They're
-		   stored in a way similar to mtf; record a starting
-		   value for the first symbol, and an offset from the
-		   previous value for everys symbol after that.
-		   (Subtracting 1 before the loop and then adding it
-		   back at the end is an optimization that makes the
-		   test inside the loop simpler: symbol length 0
-		   becomes negative, so an unsigned inequality catches
-		   it.) */
-		t = get_bits(bd, 5)-1;
-		for (i = 0; i < symCount; i++) {
-			for (;;) {
-				if (((unsigned)t) > (MAX_HUFCODE_BITS-1))
-					return RETVAL_DATA_ERROR;
-
-				/* If first bit is 0, stop.  Else
-				   second bit indicates whether to
-				   increment or decrement the value.
-				   Optimization: grab 2 bits and unget
-				   the second if the first was 0. */
-
-				k = get_bits(bd, 2);
-				if (k < 2) {
-					bd->inbufBitCount++;
-					break;
-				}
-				/* Add one if second bit 1, else
-				 * subtract 1.  Avoids if/else */
-				t += (((k+1)&2)-1);
-			}
-			/* Correct for the initial -1, to get the
-			 * final symbol length */
-			length[i] = t+1;
-		}
-		/* Find largest and smallest lengths in this group */
-		minLen = maxLen = length[0];
-
-		for (i = 1; i < symCount; i++) {
-			if (length[i] > maxLen)
-				maxLen = length[i];
-			else if (length[i] < minLen)
-				minLen = length[i];
-		}
-
-		/* Calculate permute[], base[], and limit[] tables from
-		 * length[].
-		 *
-		 * permute[] is the lookup table for converting
-		 * Huffman coded symbols into decoded symbols.  base[]
-		 * is the amount to subtract from the value of a
-		 * Huffman symbol of a given length when using
-		 * permute[].
-		 *
-		 * limit[] indicates the largest numerical value a
-		 * symbol with a given number of bits can have.  This
-		 * is how the Huffman codes can vary in length: each
-		 * code with a value > limit[length] needs another
-		 * bit.
-		 */
-		hufGroup = bd->groups+j;
-		hufGroup->minLen = minLen;
-		hufGroup->maxLen = maxLen;
-		/* Note that minLen can't be smaller than 1, so we
-		   adjust the base and limit array pointers so we're
-		   not always wasting the first entry.  We do this
-		   again when using them (during symbol decoding).*/
-		base = hufGroup->base-1;
-		limit = hufGroup->limit-1;
-		/* Calculate permute[].  Concurrently, initialize
-		 * temp[] and limit[]. */
-		pp = 0;
-		for (i = minLen; i <= maxLen; i++) {
-			temp[i] = limit[i] = 0;
-			for (t = 0; t < symCount; t++)
-				if (length[t] == i)
-					hufGroup->permute[pp++] = t;
-		}
-		/* Count symbols coded for at each bit length */
-		for (i = 0; i < symCount; i++)
-			temp[length[i]]++;
-		/* Calculate limit[] (the largest symbol-coding value
-		 *at each bit length, which is (previous limit <<
-		 *1)+symbols at this level), and base[] (number of
-		 *symbols to ignore at each bit length, which is limit
-		 *minus the cumulative count of symbols coded for
-		 *already). */
-		pp = t = 0;
-		for (i = minLen; i < maxLen; i++) {
-			pp += temp[i];
-			/* We read the largest possible symbol size
-			   and then unget bits after determining how
-			   many we need, and those extra bits could be
-			   set to anything.  (They're noise from
-			   future symbols.)  At each level we're
-			   really only interested in the first few
-			   bits, so here we set all the trailing
-			   to-be-ignored bits to 1 so they don't
-			   affect the value > limit[length]
-			   comparison. */
-			limit[i] = (pp << (maxLen - i)) - 1;
-			pp <<= 1;
-			base[i+1] = pp-(t += temp[i]);
-		}
-		limit[maxLen+1] = INT_MAX; /* Sentinal value for
-					    * reading next sym. */
-		limit[maxLen] = pp+temp[maxLen]-1;
-		base[minLen] = 0;
-	}
-	/* We've finished reading and digesting the block header.  Now
-	   read this block's Huffman coded symbols from the file and
-	   undo the Huffman coding and run length encoding, saving the
-	   result into dbuf[dbufCount++] = uc */
-
-	/* Initialize symbol occurrence counters and symbol Move To
-	 * Front table */
-	for (i = 0; i < 256; i++) {
-		byteCount[i] = 0;
-		mtfSymbol[i] = (unsigned char)i;
-	}
-	/* Loop through compressed symbols. */
-	runPos = dbufCount = symCount = selector = 0;
-	for (;;) {
-		/* Determine which Huffman coding group to use. */
-		if (!(symCount--)) {
-			symCount = GROUP_SIZE-1;
-			if (selector >= nSelectors)
-				return RETVAL_DATA_ERROR;
-			hufGroup = bd->groups+selectors[selector++];
-			base = hufGroup->base-1;
-			limit = hufGroup->limit-1;
-		}
-		/* Read next Huffman-coded symbol. */
-		/* Note: It is far cheaper to read maxLen bits and
-		   back up than it is to read minLen bits and then an
-		   additional bit at a time, testing as we go.
-		   Because there is a trailing last block (with file
-		   CRC), there is no danger of the overread causing an
-		   unexpected EOF for a valid compressed file.  As a
-		   further optimization, we do the read inline
-		   (falling back to a call to get_bits if the buffer
-		   runs dry).  The following (up to got_huff_bits:) is
-		   equivalent to j = get_bits(bd, hufGroup->maxLen);
-		 */
-		while (bd->inbufBitCount < hufGroup->maxLen) {
-			if (bd->inbufPos == bd->inbufCount) {
-				j = get_bits(bd, hufGroup->maxLen);
-				goto got_huff_bits;
-			}
-			bd->inbufBits =
-				(bd->inbufBits << 8)|bd->inbuf[bd->inbufPos++];
-			bd->inbufBitCount += 8;
-		};
-		bd->inbufBitCount -= hufGroup->maxLen;
-		j = (bd->inbufBits >> bd->inbufBitCount)&
-			((1 << hufGroup->maxLen)-1);
-got_huff_bits:
-		/* Figure how how many bits are in next symbol and
-		 * unget extras */
-		i = hufGroup->minLen;
-		while (j > limit[i])
-			++i;
-		bd->inbufBitCount += (hufGroup->maxLen - i);
-		/* Huffman decode value to get nextSym (with bounds checking) */
-		if ((i > hufGroup->maxLen)
-			|| (((unsigned)(j = (j>>(hufGroup->maxLen-i))-base[i]))
-				>= MAX_SYMBOLS))
-			return RETVAL_DATA_ERROR;
-		nextSym = hufGroup->permute[j];
-		/* We have now decoded the symbol, which indicates
-		   either a new literal byte, or a repeated run of the
-		   most recent literal byte.  First, check if nextSym
-		   indicates a repeated run, and if so loop collecting
-		   how many times to repeat the last literal. */
-		if (((unsigned)nextSym) <= SYMBOL_RUNB) { /* RUNA or RUNB */
-			/* If this is the start of a new run, zero out
-			 * counter */
-			if (!runPos) {
-				runPos = 1;
-				t = 0;
-			}
-			/* Neat trick that saves 1 symbol: instead of
-			   or-ing 0 or 1 at each bit position, add 1
-			   or 2 instead.  For example, 1011 is 1 << 0
-			   + 1 << 1 + 2 << 2.  1010 is 2 << 0 + 2 << 1
-			   + 1 << 2.  You can make any bit pattern
-			   that way using 1 less symbol than the basic
-			   or 0/1 method (except all bits 0, which
-			   would use no symbols, but a run of length 0
-			   doesn't mean anything in this context).
-			   Thus space is saved. */
-			t += (runPos << nextSym);
-			/* +runPos if RUNA; +2*runPos if RUNB */
-
-			runPos <<= 1;
-			continue;
-		}
-		/* When we hit the first non-run symbol after a run,
-		   we now know how many times to repeat the last
-		   literal, so append that many copies to our buffer
-		   of decoded symbols (dbuf) now.  (The last literal
-		   used is the one at the head of the mtfSymbol
-		   array.) */
-		if (runPos) {
-			runPos = 0;
-			if (dbufCount+t >= dbufSize)
-				return RETVAL_DATA_ERROR;
-
-			uc = symToByte[mtfSymbol[0]];
-			byteCount[uc] += t;
-			while (t--)
-				dbuf[dbufCount++] = uc;
-		}
-		/* Is this the terminating symbol? */
-		if (nextSym > symTotal)
-			break;
-		/* At this point, nextSym indicates a new literal
-		   character.  Subtract one to get the position in the
-		   MTF array at which this literal is currently to be
-		   found.  (Note that the result can't be -1 or 0,
-		   because 0 and 1 are RUNA and RUNB.  But another
-		   instance of the first symbol in the mtf array,
-		   position 0, would have been handled as part of a
-		   run above.  Therefore 1 unused mtf position minus 2
-		   non-literal nextSym values equals -1.) */
-		if (dbufCount >= dbufSize)
-			return RETVAL_DATA_ERROR;
-		i = nextSym - 1;
-		uc = mtfSymbol[i];
-		/* Adjust the MTF array.  Since we typically expect to
-		 *move only a small number of symbols, and are bound
-		 *by 256 in any case, using memmove here would
-		 *typically be bigger and slower due to function call
-		 *overhead and other assorted setup costs. */
-		do {
-			mtfSymbol[i] = mtfSymbol[i-1];
-		} while (--i);
-		mtfSymbol[0] = uc;
-		uc = symToByte[uc];
-		/* We have our literal byte.  Save it into dbuf. */
-		byteCount[uc]++;
-		dbuf[dbufCount++] = (unsigned int)uc;
-	}
-	/* At this point, we've read all the Huffman-coded symbols
-	   (and repeated runs) for this block from the input stream,
-	   and decoded them into the intermediate buffer.  There are
-	   dbufCount many decoded bytes in dbuf[].  Now undo the
-	   Burrows-Wheeler transform on dbuf.  See
-	   http://dogma.net/markn/articles/bwt/bwt.htm
-	 */
-	/* Turn byteCount into cumulative occurrence counts of 0 to n-1. */
-	j = 0;
-	for (i = 0; i < 256; i++) {
-		k = j+byteCount[i];
-		byteCount[i] = j;
-		j = k;
-	}
-	/* Figure out what order dbuf would be in if we sorted it. */
-	for (i = 0; i < dbufCount; i++) {
-		uc = (unsigned char)(dbuf[i] & 0xff);
-		dbuf[byteCount[uc]] |= (i << 8);
-		byteCount[uc]++;
-	}
-	/* Decode first byte by hand to initialize "previous" byte.
-	   Note that it doesn't get output, and if the first three
-	   characters are identical it doesn't qualify as a run (hence
-	   writeRunCountdown = 5). */
-	if (dbufCount) {
-		if (origPtr >= dbufCount)
-			return RETVAL_DATA_ERROR;
-		bd->writePos = dbuf[origPtr];
-		bd->writeCurrent = (unsigned char)(bd->writePos&0xff);
-		bd->writePos >>= 8;
-		bd->writeRunCountdown = 5;
-	}
-	bd->writeCount = dbufCount;
-
-	return RETVAL_OK;
-}
-
-/* Undo burrows-wheeler transform on intermediate buffer to produce output.
-   If start_bunzip was initialized with out_fd =-1, then up to len bytes of
-   data are written to outbuf.  Return value is number of bytes written or
-   error (all errors are negative numbers).  If out_fd!=-1, outbuf and len
-   are ignored, data is written to out_fd and return is RETVAL_OK or error.
-*/
-
-static int INIT read_bunzip(struct bunzip_data *bd, char *outbuf, int len)
-{
-	const unsigned int *dbuf;
-	int pos, xcurrent, previous, gotcount;
-
-	/* If last read was short due to end of file, return last block now */
-	if (bd->writeCount < 0)
-		return bd->writeCount;
-
-	gotcount = 0;
-	dbuf = bd->dbuf;
-	pos = bd->writePos;
-	xcurrent = bd->writeCurrent;
-
-	/* We will always have pending decoded data to write into the output
-	   buffer unless this is the very first call (in which case we haven't
-	   Huffman-decoded a block into the intermediate buffer yet). */
-
-	if (bd->writeCopies) {
-		/* Inside the loop, writeCopies means extra copies (beyond 1) */
-		--bd->writeCopies;
-		/* Loop outputting bytes */
-		for (;;) {
-			/* If the output buffer is full, snapshot
-			 * state and return */
-			if (gotcount >= len) {
-				bd->writePos = pos;
-				bd->writeCurrent = xcurrent;
-				bd->writeCopies++;
-				return len;
-			}
-			/* Write next byte into output buffer, updating CRC */
-			outbuf[gotcount++] = xcurrent;
-			bd->writeCRC = (((bd->writeCRC) << 8)
-				^bd->crc32Table[((bd->writeCRC) >> 24)
-				^xcurrent]);
-			/* Loop now if we're outputting multiple
-			 * copies of this byte */
-			if (bd->writeCopies) {
-				--bd->writeCopies;
-				continue;
-			}
-decode_next_byte:
-			if (!bd->writeCount--)
-				break;
-			/* Follow sequence vector to undo
-			 * Burrows-Wheeler transform */
-			previous = xcurrent;
-			pos = dbuf[pos];
-			xcurrent = pos&0xff;
-			pos >>= 8;
-			/* After 3 consecutive copies of the same
-			   byte, the 4th is a repeat count.  We count
-			   down from 4 instead *of counting up because
-			   testing for non-zero is faster */
-			if (--bd->writeRunCountdown) {
-				if (xcurrent != previous)
-					bd->writeRunCountdown = 4;
-			} else {
-				/* We have a repeated run, this byte
-				 * indicates the count */
-				bd->writeCopies = xcurrent;
-				xcurrent = previous;
-				bd->writeRunCountdown = 5;
-				/* Sometimes there are just 3 bytes
-				 * (run length 0) */
-				if (!bd->writeCopies)
-					goto decode_next_byte;
-				/* Subtract the 1 copy we'd output
-				 * anyway to get extras */
-				--bd->writeCopies;
-			}
-		}
-		/* Decompression of this block completed successfully */
-		bd->writeCRC = ~bd->writeCRC;
-		bd->totalCRC = ((bd->totalCRC << 1) |
-				(bd->totalCRC >> 31)) ^ bd->writeCRC;
-		/* If this block had a CRC error, force file level CRC error. */
-		if (bd->writeCRC != bd->headerCRC) {
-			bd->totalCRC = bd->headerCRC+1;
-			return RETVAL_LAST_BLOCK;
-		}
-	}
-
-	/* Refill the intermediate buffer by Huffman-decoding next
-	 * block of input */
-	/* (previous is just a convenient unused temp variable here) */
-	previous = get_next_block(bd);
-	if (previous) {
-		bd->writeCount = previous;
-		return (previous != RETVAL_LAST_BLOCK) ? previous : gotcount;
-	}
-	bd->writeCRC = 0xffffffffUL;
-	pos = bd->writePos;
-	xcurrent = bd->writeCurrent;
-	goto decode_next_byte;
-}
-
-static long INIT nofill(void *buf, unsigned long len)
-{
-	return -1;
-}
-
-/* Allocate the structure, read file header.  If in_fd ==-1, inbuf must contain
-   a complete bunzip file (len bytes long).  If in_fd!=-1, inbuf and len are
-   ignored, and data is read from file handle into temporary buffer. */
-static int INIT start_bunzip(struct bunzip_data **bdp, void *inbuf, long len,
-			     long (*fill)(void*, unsigned long))
-{
-	struct bunzip_data *bd;
-	unsigned int i, j, c;
-	const unsigned int BZh0 =
-		(((unsigned int)'B') << 24)+(((unsigned int)'Z') << 16)
-		+(((unsigned int)'h') << 8)+(unsigned int)'0';
-
-	/* Figure out how much data to allocate */
-	i = sizeof(struct bunzip_data);
-
-	/* Allocate bunzip_data.  Most fields initialize to zero. */
-	bd = *bdp = malloc(i);
-	if (!bd)
-		return RETVAL_OUT_OF_MEMORY;
-	memset(bd, 0, sizeof(struct bunzip_data));
-	/* Setup input buffer */
-	bd->inbuf = inbuf;
-	bd->inbufCount = len;
-	if (fill != NULL)
-		bd->fill = fill;
-	else
-		bd->fill = nofill;
-
-	/* Init the CRC32 table (big endian) */
-	for (i = 0; i < 256; i++) {
-		c = i << 24;
-		for (j = 8; j; j--)
-			c = c&0x80000000 ? (c << 1)^(CRC32_POLY_BE) : (c << 1);
-		bd->crc32Table[i] = c;
-	}
-
-	/* Ensure that file starts with "BZh['1'-'9']." */
-	i = get_bits(bd, 32);
-	if (((unsigned int)(i-BZh0-1)) >= 9)
-		return RETVAL_NOT_BZIP_DATA;
-
-	/* Fourth byte (ascii '1'-'9'), indicates block size in units of 100k of
-	   uncompressed data.  Allocate intermediate buffer for block. */
-	bd->dbufSize = 100000*(i-BZh0);
-
-	bd->dbuf = large_malloc(bd->dbufSize * sizeof(int));
-	if (!bd->dbuf)
-		return RETVAL_OUT_OF_MEMORY;
-	return RETVAL_OK;
-}
-
-/* Example usage: decompress src_fd to dst_fd.  (Stops at end of bzip2 data,
-   not end of file.) */
-STATIC int INIT bunzip2(unsigned char *buf, long len,
-			long (*fill)(void*, unsigned long),
-			long (*flush)(void*, unsigned long),
-			unsigned char *outbuf,
-			long *pos,
-			void(*error)(char *x))
-{
-	struct bunzip_data *bd;
-	int i = -1;
-	unsigned char *inbuf;
-
-	if (flush)
-		outbuf = malloc(BZIP2_IOBUF_SIZE);
-
-	if (!outbuf) {
-		error("Could not allocate output buffer");
-		return RETVAL_OUT_OF_MEMORY;
-	}
-	if (buf)
-		inbuf = buf;
-	else
-		inbuf = malloc(BZIP2_IOBUF_SIZE);
-	if (!inbuf) {
-		error("Could not allocate input buffer");
-		i = RETVAL_OUT_OF_MEMORY;
-		goto exit_0;
-	}
-	i = start_bunzip(&bd, inbuf, len, fill);
-	if (!i) {
-		for (;;) {
-			i = read_bunzip(bd, outbuf, BZIP2_IOBUF_SIZE);
-			if (i <= 0)
-				break;
-			if (!flush)
-				outbuf += i;
-			else
-				if (i != flush(outbuf, i)) {
-					i = RETVAL_UNEXPECTED_OUTPUT_EOF;
-					break;
-				}
-		}
-	}
-	/* Check CRC and release memory */
-	if (i == RETVAL_LAST_BLOCK) {
-		if (bd->headerCRC != bd->totalCRC)
-			error("Data integrity error when decompressing.");
-		else
-			i = RETVAL_OK;
-	} else if (i == RETVAL_UNEXPECTED_OUTPUT_EOF) {
-		error("Compressed file ends unexpectedly");
-	}
-	if (!bd)
-		goto exit_1;
-	if (bd->dbuf)
-		large_free(bd->dbuf);
-	if (pos)
-		*pos = bd->inbufPos;
-	free(bd);
-exit_1:
-	if (!buf)
-		free(inbuf);
-exit_0:
-	if (flush)
-		free(outbuf);
-	return i;
-}
-
-#ifdef PREBOOT
-STATIC int INIT __decompress(unsigned char *buf, long len,
-			long (*fill)(void*, unsigned long),
-			long (*flush)(void*, unsigned long),
-			unsigned char *outbuf, long olen,
-			long *pos,
-			void (*error)(char *x))
-{
-	return bunzip2(buf, len - 4, fill, flush, outbuf, pos, error);
-}
-#endif
diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib
index e79bb1444b29..b7b55cc4d743 100644
--- a/scripts/Makefile.lib
+++ b/scripts/Makefile.lib
@@ -294,10 +294,10 @@ $(obj)/%.dtb: $(src)/%.dts $(DTC) FORCE
 
 dtc-tmp = $(subst $(comma),_,$(dot-target).dts.tmp)
 
-# Bzip2
+# Lzma
 # ---------------------------------------------------------------------------
 
-# Bzip2 and LZMA do not include size in file... so we have to fake that;
+# LZMA does not include size in file... so we have to fake that;
 # append the size as a 32-bit littleendian number as gzip does.
 size_append = printf $(shell						\
 dec_size=0;								\
@@ -314,14 +314,6 @@ printf "%08x\n" $$dec_size |						\
 	}								\
 )
 
-quiet_cmd_bzip2 = BZIP2   $@
-cmd_bzip2 = (cat $(filter-out FORCE,$^) | \
-	bzip2 -9 && $(call size_append, $(filter-out FORCE,$^))) > $@ || \
-	(rm -f $@ ; false)
-
-# Lzma
-# ---------------------------------------------------------------------------
-
 quiet_cmd_lzma = LZMA    $@
 cmd_lzma = (cat $(filter-out FORCE,$^) | \
 	lzma -9 && $(call size_append, $(filter-out FORCE,$^))) > $@ || \
-- 
2.19.1

[PATCH 15/17] lib: Completely purge now-unused lzma code from the kernel

[Adam Borowski]

The XZ library already can decompress lzma, this other copy was redundant.
We just removed rather than converted all old users.

Signed-off-by: Adam Borowski <kilobyte@angband.pl>
---
 include/linux/decompress/unlzma.h |  13 -
 lib/Makefile                      |   1 -
 lib/decompress.c                  |   5 -
 lib/decompress_unlzma.c           | 679 ------------------------------
 4 files changed, 698 deletions(-)
 delete mode 100644 include/linux/decompress/unlzma.h
 delete mode 100644 lib/decompress_unlzma.c

diff --git a/include/linux/decompress/unlzma.h b/include/linux/decompress/unlzma.h
deleted file mode 100644
index 1c930f125182..000000000000
--- a/include/linux/decompress/unlzma.h
+++ /dev/null
@@ -1,13 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef DECOMPRESS_UNLZMA_H
-#define DECOMPRESS_UNLZMA_H
-
-int unlzma(unsigned char *, long,
-	   long (*fill)(void*, unsigned long),
-	   long (*flush)(void*, unsigned long),
-	   unsigned char *output,
-	   long *posp,
-	   void(*error)(char *x)
-	);
-
-#endif
diff --git a/lib/Makefile b/lib/Makefile
index 4c1905e6d3a7..0036af71f4a8 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -134,7 +134,6 @@ obj-$(CONFIG_XZ_DEC) += xz/
 obj-$(CONFIG_RAID6_PQ) += raid6/
 
 lib-$(CONFIG_DECOMPRESS_GZIP) += decompress_inflate.o
-lib-$(CONFIG_DECOMPRESS_LZMA) += decompress_unlzma.o
 lib-$(CONFIG_DECOMPRESS_XZ) += decompress_unxz.o
 lib-$(CONFIG_DECOMPRESS_LZO) += decompress_unlzo.o
 lib-$(CONFIG_DECOMPRESS_LZ4) += decompress_unlz4.o
diff --git a/lib/decompress.c b/lib/decompress.c
index 60f05122b9da..95f39a14eb7b 100644
--- a/lib/decompress.c
+++ b/lib/decompress.c
@@ -8,7 +8,6 @@
 #include <linux/decompress/generic.h>
 
 #include <linux/decompress/bunzip2.h>
-#include <linux/decompress/unlzma.h>
 #include <linux/decompress/unxz.h>
 #include <linux/decompress/inflate.h>
 #include <linux/decompress/unlzo.h>
@@ -23,9 +22,6 @@
 #ifndef CONFIG_DECOMPRESS_GZIP
 # define gunzip NULL
 #endif
-#ifndef CONFIG_DECOMPRESS_LZMA
-# define unlzma NULL
-#endif
 #ifndef CONFIG_DECOMPRESS_XZ
 # define unxz NULL
 #endif
@@ -48,7 +44,6 @@ struct compress_format {
 static const struct compress_format compressed_formats[] __initconst = {
 	{ {0x1f, 0x8b}, "gzip", gunzip },
 	{ {0x1f, 0x9e}, "gzip", gunzip },
-	{ {0x5d, 0x00}, "lzma", unlzma },
 	{ {0xfd, 0x37}, "xz", unxz },
 	{ {0x89, 0x4c}, "lzo", unlzo },
 	{ {0x02, 0x21}, "lz4", unlz4 },
diff --git a/lib/decompress_unlzma.c b/lib/decompress_unlzma.c
deleted file mode 100644
index ed7a1fd819f2..000000000000
--- a/lib/decompress_unlzma.c
+++ /dev/null
@@ -1,679 +0,0 @@
-/* Lzma decompressor for Linux kernel. Shamelessly snarfed
- *from busybox 1.1.1
- *
- *Linux kernel adaptation
- *Copyright (C) 2006  Alain < alain@knaff.lu >
- *
- *Based on small lzma deflate implementation/Small range coder
- *implementation for lzma.
- *Copyright (C) 2006  Aurelien Jacobs < aurel@gnuage.org >
- *
- *Based on LzmaDecode.c from the LZMA SDK 4.22 (http://www.7-zip.org/)
- *Copyright (C) 1999-2005  Igor Pavlov
- *
- *Copyrights of the parts, see headers below.
- *
- *
- *This program is free software; you can redistribute it and/or
- *modify it under the terms of the GNU Lesser General Public
- *License as published by the Free Software Foundation; either
- *version 2.1 of the License, 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
- *Lesser General Public License for more details.
- *
- *You should have received a copy of the GNU Lesser General Public
- *License along with this library; if not, write to the Free Software
- *Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
- */
-
-#ifdef STATIC
-#define PREBOOT
-#else
-#include <linux/decompress/unlzma.h>
-#endif /* STATIC */
-
-#include <linux/decompress/mm.h>
-
-#define	MIN(a, b) (((a) < (b)) ? (a) : (b))
-
-static long long INIT read_int(unsigned char *ptr, int size)
-{
-	int i;
-	long long ret = 0;
-
-	for (i = 0; i < size; i++)
-		ret = (ret << 8) | ptr[size-i-1];
-	return ret;
-}
-
-#define ENDIAN_CONVERT(x) \
-  x = (typeof(x))read_int((unsigned char *)&x, sizeof(x))
-
-
-/* Small range coder implementation for lzma.
- *Copyright (C) 2006  Aurelien Jacobs < aurel@gnuage.org >
- *
- *Based on LzmaDecode.c from the LZMA SDK 4.22 (http://www.7-zip.org/)
- *Copyright (c) 1999-2005  Igor Pavlov
- */
-
-#include <linux/compiler.h>
-
-#define LZMA_IOBUF_SIZE	0x10000
-
-struct rc {
-	long (*fill)(void*, unsigned long);
-	uint8_t *ptr;
-	uint8_t *buffer;
-	uint8_t *buffer_end;
-	long buffer_size;
-	uint32_t code;
-	uint32_t range;
-	uint32_t bound;
-	void (*error)(char *);
-};
-
-
-#define RC_TOP_BITS 24
-#define RC_MOVE_BITS 5
-#define RC_MODEL_TOTAL_BITS 11
-
-
-static long INIT nofill(void *buffer, unsigned long len)
-{
-	return -1;
-}
-
-/* Called twice: once at startup and once in rc_normalize() */
-static void INIT rc_read(struct rc *rc)
-{
-	rc->buffer_size = rc->fill((char *)rc->buffer, LZMA_IOBUF_SIZE);
-	if (rc->buffer_size <= 0)
-		rc->error("unexpected EOF");
-	rc->ptr = rc->buffer;
-	rc->buffer_end = rc->buffer + rc->buffer_size;
-}
-
-/* Called once */
-static inline void INIT rc_init(struct rc *rc,
-				       long (*fill)(void*, unsigned long),
-				       char *buffer, long buffer_size)
-{
-	if (fill)
-		rc->fill = fill;
-	else
-		rc->fill = nofill;
-	rc->buffer = (uint8_t *)buffer;
-	rc->buffer_size = buffer_size;
-	rc->buffer_end = rc->buffer + rc->buffer_size;
-	rc->ptr = rc->buffer;
-
-	rc->code = 0;
-	rc->range = 0xFFFFFFFF;
-}
-
-static inline void INIT rc_init_code(struct rc *rc)
-{
-	int i;
-
-	for (i = 0; i < 5; i++) {
-		if (rc->ptr >= rc->buffer_end)
-			rc_read(rc);
-		rc->code = (rc->code << 8) | *rc->ptr++;
-	}
-}
-
-
-/* Called twice, but one callsite is in inline'd rc_is_bit_0_helper() */
-static void INIT rc_do_normalize(struct rc *rc)
-{
-	if (rc->ptr >= rc->buffer_end)
-		rc_read(rc);
-	rc->range <<= 8;
-	rc->code = (rc->code << 8) | *rc->ptr++;
-}
-static inline void INIT rc_normalize(struct rc *rc)
-{
-	if (rc->range < (1 << RC_TOP_BITS))
-		rc_do_normalize(rc);
-}
-
-/* Called 9 times */
-/* Why rc_is_bit_0_helper exists?
- *Because we want to always expose (rc->code < rc->bound) to optimizer
- */
-static inline uint32_t INIT rc_is_bit_0_helper(struct rc *rc, uint16_t *p)
-{
-	rc_normalize(rc);
-	rc->bound = *p * (rc->range >> RC_MODEL_TOTAL_BITS);
-	return rc->bound;
-}
-static inline int INIT rc_is_bit_0(struct rc *rc, uint16_t *p)
-{
-	uint32_t t = rc_is_bit_0_helper(rc, p);
-	return rc->code < t;
-}
-
-/* Called ~10 times, but very small, thus inlined */
-static inline void INIT rc_update_bit_0(struct rc *rc, uint16_t *p)
-{
-	rc->range = rc->bound;
-	*p += ((1 << RC_MODEL_TOTAL_BITS) - *p) >> RC_MOVE_BITS;
-}
-static inline void INIT rc_update_bit_1(struct rc *rc, uint16_t *p)
-{
-	rc->range -= rc->bound;
-	rc->code -= rc->bound;
-	*p -= *p >> RC_MOVE_BITS;
-}
-
-/* Called 4 times in unlzma loop */
-static int INIT rc_get_bit(struct rc *rc, uint16_t *p, int *symbol)
-{
-	if (rc_is_bit_0(rc, p)) {
-		rc_update_bit_0(rc, p);
-		*symbol *= 2;
-		return 0;
-	} else {
-		rc_update_bit_1(rc, p);
-		*symbol = *symbol * 2 + 1;
-		return 1;
-	}
-}
-
-/* Called once */
-static inline int INIT rc_direct_bit(struct rc *rc)
-{
-	rc_normalize(rc);
-	rc->range >>= 1;
-	if (rc->code >= rc->range) {
-		rc->code -= rc->range;
-		return 1;
-	}
-	return 0;
-}
-
-/* Called twice */
-static inline void INIT
-rc_bit_tree_decode(struct rc *rc, uint16_t *p, int num_levels, int *symbol)
-{
-	int i = num_levels;
-
-	*symbol = 1;
-	while (i--)
-		rc_get_bit(rc, p + *symbol, symbol);
-	*symbol -= 1 << num_levels;
-}
-
-
-/*
- * Small lzma deflate implementation.
- * Copyright (C) 2006  Aurelien Jacobs < aurel@gnuage.org >
- *
- * Based on LzmaDecode.c from the LZMA SDK 4.22 (http://www.7-zip.org/)
- * Copyright (C) 1999-2005  Igor Pavlov
- */
-
-
-struct lzma_header {
-	uint8_t pos;
-	uint32_t dict_size;
-	uint64_t dst_size;
-} __attribute__ ((packed)) ;
-
-
-#define LZMA_BASE_SIZE 1846
-#define LZMA_LIT_SIZE 768
-
-#define LZMA_NUM_POS_BITS_MAX 4
-
-#define LZMA_LEN_NUM_LOW_BITS 3
-#define LZMA_LEN_NUM_MID_BITS 3
-#define LZMA_LEN_NUM_HIGH_BITS 8
-
-#define LZMA_LEN_CHOICE 0
-#define LZMA_LEN_CHOICE_2 (LZMA_LEN_CHOICE + 1)
-#define LZMA_LEN_LOW (LZMA_LEN_CHOICE_2 + 1)
-#define LZMA_LEN_MID (LZMA_LEN_LOW \
-		      + (1 << (LZMA_NUM_POS_BITS_MAX + LZMA_LEN_NUM_LOW_BITS)))
-#define LZMA_LEN_HIGH (LZMA_LEN_MID \
-		       +(1 << (LZMA_NUM_POS_BITS_MAX + LZMA_LEN_NUM_MID_BITS)))
-#define LZMA_NUM_LEN_PROBS (LZMA_LEN_HIGH + (1 << LZMA_LEN_NUM_HIGH_BITS))
-
-#define LZMA_NUM_STATES 12
-#define LZMA_NUM_LIT_STATES 7
-
-#define LZMA_START_POS_MODEL_INDEX 4
-#define LZMA_END_POS_MODEL_INDEX 14
-#define LZMA_NUM_FULL_DISTANCES (1 << (LZMA_END_POS_MODEL_INDEX >> 1))
-
-#define LZMA_NUM_POS_SLOT_BITS 6
-#define LZMA_NUM_LEN_TO_POS_STATES 4
-
-#define LZMA_NUM_ALIGN_BITS 4
-
-#define LZMA_MATCH_MIN_LEN 2
-
-#define LZMA_IS_MATCH 0
-#define LZMA_IS_REP (LZMA_IS_MATCH + (LZMA_NUM_STATES << LZMA_NUM_POS_BITS_MAX))
-#define LZMA_IS_REP_G0 (LZMA_IS_REP + LZMA_NUM_STATES)
-#define LZMA_IS_REP_G1 (LZMA_IS_REP_G0 + LZMA_NUM_STATES)
-#define LZMA_IS_REP_G2 (LZMA_IS_REP_G1 + LZMA_NUM_STATES)
-#define LZMA_IS_REP_0_LONG (LZMA_IS_REP_G2 + LZMA_NUM_STATES)
-#define LZMA_POS_SLOT (LZMA_IS_REP_0_LONG \
-		       + (LZMA_NUM_STATES << LZMA_NUM_POS_BITS_MAX))
-#define LZMA_SPEC_POS (LZMA_POS_SLOT \
-		       +(LZMA_NUM_LEN_TO_POS_STATES << LZMA_NUM_POS_SLOT_BITS))
-#define LZMA_ALIGN (LZMA_SPEC_POS \
-		    + LZMA_NUM_FULL_DISTANCES - LZMA_END_POS_MODEL_INDEX)
-#define LZMA_LEN_CODER (LZMA_ALIGN + (1 << LZMA_NUM_ALIGN_BITS))
-#define LZMA_REP_LEN_CODER (LZMA_LEN_CODER + LZMA_NUM_LEN_PROBS)
-#define LZMA_LITERAL (LZMA_REP_LEN_CODER + LZMA_NUM_LEN_PROBS)
-
-
-struct writer {
-	uint8_t *buffer;
-	uint8_t previous_byte;
-	size_t buffer_pos;
-	int bufsize;
-	size_t global_pos;
-	long (*flush)(void*, unsigned long);
-	struct lzma_header *header;
-};
-
-struct cstate {
-	int state;
-	uint32_t rep0, rep1, rep2, rep3;
-};
-
-static inline size_t INIT get_pos(struct writer *wr)
-{
-	return
-		wr->global_pos + wr->buffer_pos;
-}
-
-static inline uint8_t INIT peek_old_byte(struct writer *wr,
-						uint32_t offs)
-{
-	if (!wr->flush) {
-		int32_t pos;
-		while (offs > wr->header->dict_size)
-			offs -= wr->header->dict_size;
-		pos = wr->buffer_pos - offs;
-		return wr->buffer[pos];
-	} else {
-		uint32_t pos = wr->buffer_pos - offs;
-		while (pos >= wr->header->dict_size)
-			pos += wr->header->dict_size;
-		return wr->buffer[pos];
-	}
-
-}
-
-static inline int INIT write_byte(struct writer *wr, uint8_t byte)
-{
-	wr->buffer[wr->buffer_pos++] = wr->previous_byte = byte;
-	if (wr->flush && wr->buffer_pos == wr->header->dict_size) {
-		wr->buffer_pos = 0;
-		wr->global_pos += wr->header->dict_size;
-		if (wr->flush((char *)wr->buffer, wr->header->dict_size)
-				!= wr->header->dict_size)
-			return -1;
-	}
-	return 0;
-}
-
-
-static inline int INIT copy_byte(struct writer *wr, uint32_t offs)
-{
-	return write_byte(wr, peek_old_byte(wr, offs));
-}
-
-static inline int INIT copy_bytes(struct writer *wr,
-					 uint32_t rep0, int len)
-{
-	do {
-		if (copy_byte(wr, rep0))
-			return -1;
-		len--;
-	} while (len != 0 && wr->buffer_pos < wr->header->dst_size);
-
-	return len;
-}
-
-static inline int INIT process_bit0(struct writer *wr, struct rc *rc,
-				     struct cstate *cst, uint16_t *p,
-				     int pos_state, uint16_t *prob,
-				     int lc, uint32_t literal_pos_mask) {
-	int mi = 1;
-	rc_update_bit_0(rc, prob);
-	prob = (p + LZMA_LITERAL +
-		(LZMA_LIT_SIZE
-		 * (((get_pos(wr) & literal_pos_mask) << lc)
-		    + (wr->previous_byte >> (8 - lc))))
-		);
-
-	if (cst->state >= LZMA_NUM_LIT_STATES) {
-		int match_byte = peek_old_byte(wr, cst->rep0);
-		do {
-			int bit;
-			uint16_t *prob_lit;
-
-			match_byte <<= 1;
-			bit = match_byte & 0x100;
-			prob_lit = prob + 0x100 + bit + mi;
-			if (rc_get_bit(rc, prob_lit, &mi)) {
-				if (!bit)
-					break;
-			} else {
-				if (bit)
-					break;
-			}
-		} while (mi < 0x100);
-	}
-	while (mi < 0x100) {
-		uint16_t *prob_lit = prob + mi;
-		rc_get_bit(rc, prob_lit, &mi);
-	}
-	if (cst->state < 4)
-		cst->state = 0;
-	else if (cst->state < 10)
-		cst->state -= 3;
-	else
-		cst->state -= 6;
-
-	return write_byte(wr, mi);
-}
-
-static inline int INIT process_bit1(struct writer *wr, struct rc *rc,
-					    struct cstate *cst, uint16_t *p,
-					    int pos_state, uint16_t *prob) {
-  int offset;
-	uint16_t *prob_len;
-	int num_bits;
-	int len;
-
-	rc_update_bit_1(rc, prob);
-	prob = p + LZMA_IS_REP + cst->state;
-	if (rc_is_bit_0(rc, prob)) {
-		rc_update_bit_0(rc, prob);
-		cst->rep3 = cst->rep2;
-		cst->rep2 = cst->rep1;
-		cst->rep1 = cst->rep0;
-		cst->state = cst->state < LZMA_NUM_LIT_STATES ? 0 : 3;
-		prob = p + LZMA_LEN_CODER;
-	} else {
-		rc_update_bit_1(rc, prob);
-		prob = p + LZMA_IS_REP_G0 + cst->state;
-		if (rc_is_bit_0(rc, prob)) {
-			rc_update_bit_0(rc, prob);
-			prob = (p + LZMA_IS_REP_0_LONG
-				+ (cst->state <<
-				   LZMA_NUM_POS_BITS_MAX) +
-				pos_state);
-			if (rc_is_bit_0(rc, prob)) {
-				rc_update_bit_0(rc, prob);
-
-				cst->state = cst->state < LZMA_NUM_LIT_STATES ?
-					9 : 11;
-				return copy_byte(wr, cst->rep0);
-			} else {
-				rc_update_bit_1(rc, prob);
-			}
-		} else {
-			uint32_t distance;
-
-			rc_update_bit_1(rc, prob);
-			prob = p + LZMA_IS_REP_G1 + cst->state;
-			if (rc_is_bit_0(rc, prob)) {
-				rc_update_bit_0(rc, prob);
-				distance = cst->rep1;
-			} else {
-				rc_update_bit_1(rc, prob);
-				prob = p + LZMA_IS_REP_G2 + cst->state;
-				if (rc_is_bit_0(rc, prob)) {
-					rc_update_bit_0(rc, prob);
-					distance = cst->rep2;
-				} else {
-					rc_update_bit_1(rc, prob);
-					distance = cst->rep3;
-					cst->rep3 = cst->rep2;
-				}
-				cst->rep2 = cst->rep1;
-			}
-			cst->rep1 = cst->rep0;
-			cst->rep0 = distance;
-		}
-		cst->state = cst->state < LZMA_NUM_LIT_STATES ? 8 : 11;
-		prob = p + LZMA_REP_LEN_CODER;
-	}
-
-	prob_len = prob + LZMA_LEN_CHOICE;
-	if (rc_is_bit_0(rc, prob_len)) {
-		rc_update_bit_0(rc, prob_len);
-		prob_len = (prob + LZMA_LEN_LOW
-			    + (pos_state <<
-			       LZMA_LEN_NUM_LOW_BITS));
-		offset = 0;
-		num_bits = LZMA_LEN_NUM_LOW_BITS;
-	} else {
-		rc_update_bit_1(rc, prob_len);
-		prob_len = prob + LZMA_LEN_CHOICE_2;
-		if (rc_is_bit_0(rc, prob_len)) {
-			rc_update_bit_0(rc, prob_len);
-			prob_len = (prob + LZMA_LEN_MID
-				    + (pos_state <<
-				       LZMA_LEN_NUM_MID_BITS));
-			offset = 1 << LZMA_LEN_NUM_LOW_BITS;
-			num_bits = LZMA_LEN_NUM_MID_BITS;
-		} else {
-			rc_update_bit_1(rc, prob_len);
-			prob_len = prob + LZMA_LEN_HIGH;
-			offset = ((1 << LZMA_LEN_NUM_LOW_BITS)
-				  + (1 << LZMA_LEN_NUM_MID_BITS));
-			num_bits = LZMA_LEN_NUM_HIGH_BITS;
-		}
-	}
-
-	rc_bit_tree_decode(rc, prob_len, num_bits, &len);
-	len += offset;
-
-	if (cst->state < 4) {
-		int pos_slot;
-
-		cst->state += LZMA_NUM_LIT_STATES;
-		prob =
-			p + LZMA_POS_SLOT +
-			((len <
-			  LZMA_NUM_LEN_TO_POS_STATES ? len :
-			  LZMA_NUM_LEN_TO_POS_STATES - 1)
-			 << LZMA_NUM_POS_SLOT_BITS);
-		rc_bit_tree_decode(rc, prob,
-				   LZMA_NUM_POS_SLOT_BITS,
-				   &pos_slot);
-		if (pos_slot >= LZMA_START_POS_MODEL_INDEX) {
-			int i, mi;
-			num_bits = (pos_slot >> 1) - 1;
-			cst->rep0 = 2 | (pos_slot & 1);
-			if (pos_slot < LZMA_END_POS_MODEL_INDEX) {
-				cst->rep0 <<= num_bits;
-				prob = p + LZMA_SPEC_POS +
-					cst->rep0 - pos_slot - 1;
-			} else {
-				num_bits -= LZMA_NUM_ALIGN_BITS;
-				while (num_bits--)
-					cst->rep0 = (cst->rep0 << 1) |
-						rc_direct_bit(rc);
-				prob = p + LZMA_ALIGN;
-				cst->rep0 <<= LZMA_NUM_ALIGN_BITS;
-				num_bits = LZMA_NUM_ALIGN_BITS;
-			}
-			i = 1;
-			mi = 1;
-			while (num_bits--) {
-				if (rc_get_bit(rc, prob + mi, &mi))
-					cst->rep0 |= i;
-				i <<= 1;
-			}
-		} else
-			cst->rep0 = pos_slot;
-		if (++(cst->rep0) == 0)
-			return 0;
-		if (cst->rep0 > wr->header->dict_size
-				|| cst->rep0 > get_pos(wr))
-			return -1;
-	}
-
-	len += LZMA_MATCH_MIN_LEN;
-
-	return copy_bytes(wr, cst->rep0, len);
-}
-
-
-
-STATIC inline int INIT unlzma(unsigned char *buf, long in_len,
-			      long (*fill)(void*, unsigned long),
-			      long (*flush)(void*, unsigned long),
-			      unsigned char *output,
-			      long *posp,
-			      void(*error)(char *x)
-	)
-{
-	struct lzma_header header;
-	int lc, pb, lp;
-	uint32_t pos_state_mask;
-	uint32_t literal_pos_mask;
-	uint16_t *p;
-	int num_probs;
-	struct rc rc;
-	int i, mi;
-	struct writer wr;
-	struct cstate cst;
-	unsigned char *inbuf;
-	int ret = -1;
-
-	rc.error = error;
-
-	if (buf)
-		inbuf = buf;
-	else
-		inbuf = malloc(LZMA_IOBUF_SIZE);
-	if (!inbuf) {
-		error("Could not allocate input buffer");
-		goto exit_0;
-	}
-
-	cst.state = 0;
-	cst.rep0 = cst.rep1 = cst.rep2 = cst.rep3 = 1;
-
-	wr.header = &header;
-	wr.flush = flush;
-	wr.global_pos = 0;
-	wr.previous_byte = 0;
-	wr.buffer_pos = 0;
-
-	rc_init(&rc, fill, inbuf, in_len);
-
-	for (i = 0; i < sizeof(header); i++) {
-		if (rc.ptr >= rc.buffer_end)
-			rc_read(&rc);
-		((unsigned char *)&header)[i] = *rc.ptr++;
-	}
-
-	if (header.pos >= (9 * 5 * 5)) {
-		error("bad header");
-		goto exit_1;
-	}
-
-	mi = 0;
-	lc = header.pos;
-	while (lc >= 9) {
-		mi++;
-		lc -= 9;
-	}
-	pb = 0;
-	lp = mi;
-	while (lp >= 5) {
-		pb++;
-		lp -= 5;
-	}
-	pos_state_mask = (1 << pb) - 1;
-	literal_pos_mask = (1 << lp) - 1;
-
-	ENDIAN_CONVERT(header.dict_size);
-	ENDIAN_CONVERT(header.dst_size);
-
-	if (header.dict_size == 0)
-		header.dict_size = 1;
-
-	if (output)
-		wr.buffer = output;
-	else {
-		wr.bufsize = MIN(header.dst_size, header.dict_size);
-		wr.buffer = large_malloc(wr.bufsize);
-	}
-	if (wr.buffer == NULL)
-		goto exit_1;
-
-	num_probs = LZMA_BASE_SIZE + (LZMA_LIT_SIZE << (lc + lp));
-	p = (uint16_t *) large_malloc(num_probs * sizeof(*p));
-	if (p == NULL)
-		goto exit_2;
-	num_probs = LZMA_LITERAL + (LZMA_LIT_SIZE << (lc + lp));
-	for (i = 0; i < num_probs; i++)
-		p[i] = (1 << RC_MODEL_TOTAL_BITS) >> 1;
-
-	rc_init_code(&rc);
-
-	while (get_pos(&wr) < header.dst_size) {
-		int pos_state =	get_pos(&wr) & pos_state_mask;
-		uint16_t *prob = p + LZMA_IS_MATCH +
-			(cst.state << LZMA_NUM_POS_BITS_MAX) + pos_state;
-		if (rc_is_bit_0(&rc, prob)) {
-			if (process_bit0(&wr, &rc, &cst, p, pos_state, prob,
-					lc, literal_pos_mask)) {
-				error("LZMA data is corrupt");
-				goto exit_3;
-			}
-		} else {
-			if (process_bit1(&wr, &rc, &cst, p, pos_state, prob)) {
-				error("LZMA data is corrupt");
-				goto exit_3;
-			}
-			if (cst.rep0 == 0)
-				break;
-		}
-		if (rc.buffer_size <= 0)
-			goto exit_3;
-	}
-
-	if (posp)
-		*posp = rc.ptr-rc.buffer;
-	if (!wr.flush || wr.flush(wr.buffer, wr.buffer_pos) == wr.buffer_pos)
-		ret = 0;
-exit_3:
-	large_free(p);
-exit_2:
-	if (!output)
-		large_free(wr.buffer);
-exit_1:
-	if (!buf)
-		free(inbuf);
-exit_0:
-	return ret;
-}
-
-#ifdef PREBOOT
-STATIC int INIT __decompress(unsigned char *buf, long in_len,
-			      long (*fill)(void*, unsigned long),
-			      long (*flush)(void*, unsigned long),
-			      unsigned char *output, long out_len,
-			      long *posp,
-			      void (*error)(char *x))
-{
-	return unlzma(buf, in_len - 4, fill, flush, output, posp, error);
-}
-#endif
-- 
2.19.1

[PATCH 16/17] Kconfig: Update the prose for selection of compression algorithm

[Adam Borowski]

It was really obsolete, and some entries contradicted each other.

Let's not recommend ZSTD for kernel compression yet as it's available
only on x86, and some distros might not have the tool installed.
Proposing ZSTD for initrd is safer but let's test it first.

Signed-off-by: Adam Borowski <kilobyte@angband.pl>
---
 init/Kconfig | 25 +++++++++++++------------
 usr/Kconfig  | 24 +++++++++++-------------
 2 files changed, 24 insertions(+), 25 deletions(-)

diff --git a/init/Kconfig b/init/Kconfig
index 412ba93673fa..7c0180c41a3c 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -153,26 +153,27 @@ choice
 	  version of this functionality (bzip2 only), for 2.4, was
 	  supplied by Christian Ludwig)
 
-	  High compression options are mostly useful for users, who
-	  are low on disk space (embedded systems), but for whom ram
-	  size matters less.
+	  High compression options tend to be more useful in most cases,
+	  as bootloaders are often egregiously slow to read the kernel
+	  from the disk/SD card/network/etc, overcoming any boot time
+	  savings you would get from faster decompression.
 
-	  If in doubt, select 'gzip'
+	  If in doubt, select 'xz'
 
 config KERNEL_GZIP
 	bool "Gzip"
 	depends on HAVE_KERNEL_GZIP
 	help
-	  The old and tried gzip compression. It provides a good balance
-	  between compression ratio and decompression speed.
+	  The old and tried gzip compression. You generally want it if
+	  some tool you use doesn't support more modern compressors.
 
 config KERNEL_LZMA
 	bool "LZMA"
 	depends on HAVE_KERNEL_LZMA
 	help
-	  This compression algorithm's ratio is best.  Decompression speed
-	  is between gzip and bzip2.  Compression is slowest.
-	  The kernel size is about 33% smaller with LZMA in comparison to gzip.
+	  An old version of xz, like it providing strong compression at slow
+	  speed. It lacks a header and support for filters or uncompressed
+	  blocks, thus it's usually better to pick xz.
 
 config KERNEL_XZ
 	bool "XZ"
@@ -193,9 +194,9 @@ config KERNEL_LZO
 	bool "LZO"
 	depends on HAVE_KERNEL_LZO
 	help
-	  Its compression ratio is the poorest among the choices. The kernel
-	  size is about 10% bigger than gzip; however its speed
-	  (both compression and decompression) is the fastest.
+	  Its compression ratio is pretty poor (but still better than
+	  LZ4). You want to pick ZSTD (similar speed but much better
+	  compression) or LZ4 (much better speed) instead.
 
 config KERNEL_LZ4
 	bool "LZ4"
diff --git a/usr/Kconfig b/usr/Kconfig
index 8d99edacabc9..f6e871585f05 100644
--- a/usr/Kconfig
+++ b/usr/Kconfig
@@ -131,17 +131,15 @@ config INITRAMFS_COMPRESSION_NONE
 	  on those architectures that support this. However, not compressing the
 	  initramfs may lead to slightly higher memory consumption during a
 	  short time at boot, while both the cpio image and the unpacked
-	  filesystem image will be present in memory simultaneously
+	  filesystem image will be present in memory simultaneously.
 
 config INITRAMFS_COMPRESSION_GZIP
 	bool "Gzip"
 	depends on RD_GZIP
 	help
-	  Use the old and well tested gzip compression algorithm. Gzip provides
-	  a good balance between compression ratio and decompression speed and
-	  has a reasonable compression speed. It is also more likely to be
-	  supported by your build system as the gzip tool is present by default
-	  on most distros.
+	  Use the old and well tested gzip compression algorithm. Gzip doesn't
+	  provide very good compression nor speed, but it's the safest choice,
+	  with wide support.
 
 config INITRAMFS_COMPRESSION_XZ
 	bool "XZ"
@@ -150,20 +148,20 @@ config INITRAMFS_COMPRESSION_XZ
 	  XZ uses the LZMA2 algorithm and has a large dictionary which may cause
 	  problems on memory constrained systems. The initramfs size is about
 	  30% smaller with XZ in comparison to gzip. Decompression speed is
-	  better than that of bzip2 but worse than gzip and LZO. Compression is
-	  slow.
+	  okayish but still slowest of all currently available algorithms.
+	  Compression is slow.
 
-	  If you choose this, keep in mind that you may need to install the xz
-	  tool to be able to compress the initram.
+	  Any modern distro provides xz in its default install, but on
+	  minimal build systems you might need to install xz-utils to be
+	  able to compress the initram.
 
 config INITRAMFS_COMPRESSION_LZO
 	bool "LZO"
 	depends on RD_LZO
 	help
 	  It's compression ratio is the second poorest amongst the choices. The
-	  kernel size is about 10% bigger than gzip. Despite that, it's
-	  decompression speed is the second fastest and it's compression speed
-	  is quite fast too.
+	  kernel size is about 10% bigger than gzip. Pick ZSTD instead, or LZ4
+	  if speed is paramount.
 
 	  If you choose this, keep in mind that you may need to install the lzop
 	  tool to be able to compress the initram.
-- 
2.19.1

[PATCH 17/17] [NOT FOR MERGING] lib: Be noisy about used decompression method.

[Adam Borowski]

It's too easy to build the initrd with wrong options during testing, after
which it may silently work anyway.

Signed-off-by: Adam Borowski <kilobyte@angband.pl>
---
 lib/decompress.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/lib/decompress.c b/lib/decompress.c
index 95f39a14eb7b..345679312a45 100644
--- a/lib/decompress.c
+++ b/lib/decompress.c
@@ -69,7 +69,9 @@ decompress_fn __init decompress_method(const unsigned char *inbuf, long len,
 			break;
 
 	}
-	if (name)
+	if (name) {
 		*name = cf->name;
+		printk("Decompressing using %s.\n", *name);
+	}
 	return cf->decompressor;
 }
-- 
2.19.1