[PATCH 6/6] lib/lzo: separate lzo-rle from lzo
From: Dave Rodgman
Date: Wed Nov 21 2018 - 06:59:52 EST
To prevent any issues with persistent data, separate lzo-rle
from lzo so that it is treated as a separate algorithm, and
lzo is still available.
Use lzo-rle as the default algorithm for
zram.
Signed-off-by: Dave Rodgman <dave.rodgman@xxxxxxx>
---
Documentation/lzo.txt | 12 ++-
crypto/Makefile | 2 +-
crypto/lzo-rle.c | 171 ++++++++++++++++++++++++++++++++++++++++++
crypto/tcrypt.c | 4 +-
drivers/block/zram/zcomp.c | 1 +
drivers/block/zram/zram_drv.c | 2 +-
include/linux/lzo.h | 4 +
lib/lzo/lzo1x_compress.c | 42 ++++++++---
lib/lzo/lzodefs.h | 3 +-
9 files changed, 223 insertions(+), 18 deletions(-)
create mode 100644 crypto/lzo-rle.c
diff --git a/Documentation/lzo.txt b/Documentation/lzo.txt
index 306c60344ca7..f79934225d8d 100644
--- a/Documentation/lzo.txt
+++ b/Documentation/lzo.txt
@@ -88,6 +88,10 @@ length encoding. This improves speed for data with many zeros, which is a
common case for zram. This modifies the bitstream in a backwards compatible way
(v1 can correctly decompress v0 compressed data, but v0 cannot read v1 data).
+For maximum compatibility, both versions are available under different names
+(lzo and lzo-rle). Differences in the encoding are noted in this document with
+e.g.: version 1 only.
+
Byte sequences
==============
@@ -99,8 +103,8 @@ Byte sequences
invalid at this place.
17 : bitstream version. If the first byte is 17, the next byte
- gives the bitstream version. If the first byte is not 17,
- the bitstream version is 0.
+ gives the bitstream version (version 1 only). If the first byte
+ is not 17, the bitstream version is 0.
18..21 : copy 0..3 literals
state = (byte - 17) = 0..3 [ copy <state> literals ]
@@ -154,8 +158,8 @@ Byte sequences
state = S (copy S literals after this block)
End of stream is reached if distance == 16384
- In version 1, this instruction is also used to encode a run of zeros if
- distance = 0xbfff, i.e. H = 1 and the D bits are all 1.
+ In version 1 only, this instruction is also used to encode a run of
+ zeros if distance = 0xbfff, i.e. H = 1 and the D bits are all 1.
In this case, it is followed by a fourth byte, X.
run length = ((X << 3) | (0 0 0 0 0 L L L)) + 4.
diff --git a/crypto/Makefile b/crypto/Makefile
index 6d1d40eeb964..4b482fa11fee 100644
--- a/crypto/Makefile
+++ b/crypto/Makefile
@@ -125,7 +125,7 @@ obj-$(CONFIG_CRYPTO_CRC32C) += crc32c_generic.o
obj-$(CONFIG_CRYPTO_CRC32) += crc32_generic.o
obj-$(CONFIG_CRYPTO_CRCT10DIF) += crct10dif_common.o crct10dif_generic.o
obj-$(CONFIG_CRYPTO_AUTHENC) += authenc.o authencesn.o
-obj-$(CONFIG_CRYPTO_LZO) += lzo.o
+obj-$(CONFIG_CRYPTO_LZO) += lzo.o lzo-rle.o
obj-$(CONFIG_CRYPTO_LZ4) += lz4.o
obj-$(CONFIG_CRYPTO_LZ4HC) += lz4hc.o
obj-$(CONFIG_CRYPTO_842) += 842.o
diff --git a/crypto/lzo-rle.c b/crypto/lzo-rle.c
new file mode 100644
index 000000000000..d51baebbd8d7
--- /dev/null
+++ b/crypto/lzo-rle.c
@@ -0,0 +1,171 @@
+/*
+ * Cryptographic API.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * 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.
+ *
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/crypto.h>
+#include <linux/vmalloc.h>
+#include <linux/mm.h>
+#include <linux/lzo.h>
+#include <crypto/internal/scompress.h>
+
+struct lzorle_ctx {
+ void *lzorle_comp_mem;
+};
+
+static void *lzorle_alloc_ctx(struct crypto_scomp *tfm)
+{
+ void *ctx;
+
+ ctx = kvmalloc(LZO1X_MEM_COMPRESS, GFP_KERNEL);
+ if (!ctx)
+ return ERR_PTR(-ENOMEM);
+
+ return ctx;
+}
+
+static int lzorle_init(struct crypto_tfm *tfm)
+{
+ struct lzorle_ctx *ctx = crypto_tfm_ctx(tfm);
+
+ ctx->lzorle_comp_mem = lzorle_alloc_ctx(NULL);
+ if (IS_ERR(ctx->lzorle_comp_mem))
+ return -ENOMEM;
+
+ return 0;
+}
+
+static void lzorle_free_ctx(struct crypto_scomp *tfm, void *ctx)
+{
+ kvfree(ctx);
+}
+
+static void lzorle_exit(struct crypto_tfm *tfm)
+{
+ struct lzorle_ctx *ctx = crypto_tfm_ctx(tfm);
+
+ lzorle_free_ctx(NULL, ctx->lzorle_comp_mem);
+}
+
+static int __lzorle_compress(const u8 *src, unsigned int slen,
+ u8 *dst, unsigned int *dlen, void *ctx)
+{
+ size_t tmp_len = *dlen; /* size_t(ulong) <-> uint on 64 bit */
+ int err;
+
+ err = lzorle1x_1_compress(src, slen, dst, &tmp_len, ctx);
+
+ if (err != LZO_E_OK)
+ return -EINVAL;
+
+ *dlen = tmp_len;
+ return 0;
+}
+
+static int lzorle_compress(struct crypto_tfm *tfm, const u8 *src,
+ unsigned int slen, u8 *dst, unsigned int *dlen)
+{
+ struct lzorle_ctx *ctx = crypto_tfm_ctx(tfm);
+
+ return __lzorle_compress(src, slen, dst, dlen, ctx->lzorle_comp_mem);
+}
+
+static int lzorle_scompress(struct crypto_scomp *tfm, const u8 *src,
+ unsigned int slen, u8 *dst, unsigned int *dlen,
+ void *ctx)
+{
+ return __lzorle_compress(src, slen, dst, dlen, ctx);
+}
+
+static int __lzorle_decompress(const u8 *src, unsigned int slen,
+ u8 *dst, unsigned int *dlen)
+{
+ int err;
+ size_t tmp_len = *dlen; /* size_t(ulong) <-> uint on 64 bit */
+
+ err = lzo1x_decompress_safe(src, slen, dst, &tmp_len);
+
+ if (err != LZO_E_OK)
+ return -EINVAL;
+
+ *dlen = tmp_len;
+ return 0;
+}
+
+static int lzorle_decompress(struct crypto_tfm *tfm, const u8 *src,
+ unsigned int slen, u8 *dst, unsigned int *dlen)
+{
+ return __lzorle_decompress(src, slen, dst, dlen);
+}
+
+static int lzorle_sdecompress(struct crypto_scomp *tfm, const u8 *src,
+ unsigned int slen, u8 *dst, unsigned int *dlen,
+ void *ctx)
+{
+ return __lzorle_decompress(src, slen, dst, dlen);
+}
+
+static struct crypto_alg alg = {
+ .cra_name = "lzo-rle",
+ .cra_flags = CRYPTO_ALG_TYPE_COMPRESS,
+ .cra_ctxsize = sizeof(struct lzorle_ctx),
+ .cra_module = THIS_MODULE,
+ .cra_init = lzorle_init,
+ .cra_exit = lzorle_exit,
+ .cra_u = { .compress = {
+ .coa_compress = lzorle_compress,
+ .coa_decompress = lzorle_decompress } }
+};
+
+static struct scomp_alg scomp = {
+ .alloc_ctx = lzorle_alloc_ctx,
+ .free_ctx = lzorle_free_ctx,
+ .compress = lzorle_scompress,
+ .decompress = lzorle_sdecompress,
+ .base = {
+ .cra_name = "lzo-rle",
+ .cra_driver_name = "lzo-rle-scomp",
+ .cra_module = THIS_MODULE,
+ }
+};
+
+static int __init lzorle_mod_init(void)
+{
+ int ret;
+
+ ret = crypto_register_alg(&alg);
+ if (ret)
+ return ret;
+
+ ret = crypto_register_scomp(&scomp);
+ if (ret) {
+ crypto_unregister_alg(&alg);
+ return ret;
+ }
+
+ return ret;
+}
+
+static void __exit lzorle_mod_fini(void)
+{
+ crypto_unregister_alg(&alg);
+ crypto_unregister_scomp(&scomp);
+}
+
+module_init(lzorle_mod_init);
+module_exit(lzorle_mod_fini);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("LZO-RLE Compression Algorithm");
+MODULE_ALIAS_CRYPTO("lzo-rle");
diff --git a/crypto/tcrypt.c b/crypto/tcrypt.c
index bdde95e8d369..c154bc657e3a 100644
--- a/crypto/tcrypt.c
+++ b/crypto/tcrypt.c
@@ -76,8 +76,8 @@ static char *check[] = {
"cast6", "arc4", "michael_mic", "deflate", "crc32c", "tea", "xtea",
"khazad", "wp512", "wp384", "wp256", "tnepres", "xeta", "fcrypt",
"camellia", "seed", "salsa20", "rmd128", "rmd160", "rmd256", "rmd320",
- "lzo", "cts", "zlib", "sha3-224", "sha3-256", "sha3-384", "sha3-512",
- NULL
+ "lzo", "lzo-rle", "cts", "zlib", "sha3-224", "sha3-256", "sha3-384",
+ "sha3-512", NULL
};
static u32 block_sizes[] = { 16, 64, 256, 1024, 8192, 0 };
diff --git a/drivers/block/zram/zcomp.c b/drivers/block/zram/zcomp.c
index 4ed0a78fdc09..4d9a38890965 100644
--- a/drivers/block/zram/zcomp.c
+++ b/drivers/block/zram/zcomp.c
@@ -20,6 +20,7 @@
static const char * const backends[] = {
"lzo",
+ "lzo-rle",
#if IS_ENABLED(CONFIG_CRYPTO_LZ4)
"lz4",
#endif
diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c
index a1d6b5597c17..bc127f21d1e9 100644
--- a/drivers/block/zram/zram_drv.c
+++ b/drivers/block/zram/zram_drv.c
@@ -41,7 +41,7 @@ static DEFINE_IDR(zram_index_idr);
static DEFINE_MUTEX(zram_index_mutex);
static int zram_major;
-static const char *default_compressor = "lzo";
+static const char *default_compressor = "lzo-rle";
/* Module params (documentation at end) */
static unsigned int num_devices = 1;
diff --git a/include/linux/lzo.h b/include/linux/lzo.h
index 547a86c71e1b..e95c7d1092b2 100644
--- a/include/linux/lzo.h
+++ b/include/linux/lzo.h
@@ -24,6 +24,10 @@
int lzo1x_1_compress(const unsigned char *src, size_t src_len,
unsigned char *dst, size_t *dst_len, void *wrkmem);
+/* This requires 'wrkmem' of size LZO1X_1_MEM_COMPRESS */
+int lzorle1x_1_compress(const unsigned char *src, size_t src_len,
+ unsigned char *dst, size_t *dst_len, void *wrkmem);
+
/* safe decompression with overrun testing */
int lzo1x_decompress_safe(const unsigned char *src, size_t src_len,
unsigned char *dst, size_t *dst_len);
diff --git a/lib/lzo/lzo1x_compress.c b/lib/lzo/lzo1x_compress.c
index fa8d4ff38531..1a1cd5e84391 100644
--- a/lib/lzo/lzo1x_compress.c
+++ b/lib/lzo/lzo1x_compress.c
@@ -20,7 +20,8 @@
static noinline size_t
lzo1x_1_do_compress(const unsigned char *in, size_t in_len,
unsigned char *out, size_t *out_len,
- size_t ti, void *wrkmem, signed char *state_offset)
+ size_t ti, void *wrkmem, signed char *state_offset,
+ const unsigned char bitstream_version)
{
const unsigned char *ip;
unsigned char *op;
@@ -46,7 +47,7 @@ lzo1x_1_do_compress(const unsigned char *in, size_t in_len,
break;
dv = get_unaligned_le32(ip);
- if (dv == 0) {
+ if (dv == 0 && bitstream_version) {
const unsigned char *ir = ip + 4;
const unsigned char *limit = ip_end
< (ip + MAX_ZERO_RUN_LENGTH + 1)
@@ -282,30 +283,36 @@ lzo1x_1_do_compress(const unsigned char *in, size_t in_len,
return in_end - (ii - ti);
}
-int lzo1x_1_compress(const unsigned char *in, size_t in_len,
+int lzogeneric1x_1_compress(const unsigned char *in, size_t in_len,
unsigned char *out, size_t *out_len,
- void *wrkmem)
+ void *wrkmem, const unsigned char bitstream_version)
{
const unsigned char *ip = in;
unsigned char *op = out;
size_t l = in_len;
size_t t = 0;
signed char state_offset = -2;
+ unsigned int m4_max_offset;
// LZO v0 will never write 17 as first byte,
// so this is used to version the bitstream
- *op++ = 17;
- *op++ = LZO_VERSION;
+ if (bitstream_version > 0) {
+ *op++ = 17;
+ *op++ = bitstream_version;
+ m4_max_offset = M4_MAX_OFFSET_V1;
+ } else {
+ m4_max_offset = M4_MAX_OFFSET_V0;
+ }
while (l > 20) {
- size_t ll = l <= (M4_MAX_OFFSET + 1) ? l : (M4_MAX_OFFSET + 1);
+ size_t ll = l <= (m4_max_offset + 1) ? l : (m4_max_offset + 1);
uintptr_t ll_end = (uintptr_t) ip + ll;
if ((ll_end + ((t + ll) >> 5)) <= ll_end)
break;
BUILD_BUG_ON(D_SIZE * sizeof(lzo_dict_t) > LZO1X_1_MEM_COMPRESS);
memset(wrkmem, 0, D_SIZE * sizeof(lzo_dict_t));
- t = lzo1x_1_do_compress(ip, ll, op, out_len,
- t, wrkmem, &state_offset);
+ t = lzo1x_1_do_compress(ip, ll, op, out_len, t, wrkmem,
+ &state_offset, bitstream_version);
ip += ll;
op += *out_len;
l -= ll;
@@ -348,7 +355,24 @@ int lzo1x_1_compress(const unsigned char *in, size_t in_len,
*out_len = op - out;
return LZO_E_OK;
}
+
+int lzo1x_1_compress(const unsigned char *in, size_t in_len,
+ unsigned char *out, size_t *out_len,
+ void *wrkmem)
+{
+ return lzogeneric1x_1_compress(in, in_len, out, out_len, wrkmem, 0);
+}
+
+int lzorle1x_1_compress(const unsigned char *in, size_t in_len,
+ unsigned char *out, size_t *out_len,
+ void *wrkmem)
+{
+ return lzogeneric1x_1_compress(in, in_len, out, out_len,
+ wrkmem, LZO_VERSION);
+}
+
EXPORT_SYMBOL_GPL(lzo1x_1_compress);
+EXPORT_SYMBOL_GPL(lzorle1x_1_compress);
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("LZO1X-1 Compressor");
diff --git a/lib/lzo/lzodefs.h b/lib/lzo/lzodefs.h
index 436bb400ac87..60b5c63afcdb 100644
--- a/lib/lzo/lzodefs.h
+++ b/lib/lzo/lzodefs.h
@@ -52,7 +52,8 @@
#define M1_MAX_OFFSET 0x0400
#define M2_MAX_OFFSET 0x0800
#define M3_MAX_OFFSET 0x4000
-#define M4_MAX_OFFSET 0xbffe
+#define M4_MAX_OFFSET_V0 0xbfff
+#define M4_MAX_OFFSET_V1 0xbffe
#define M1_MIN_LEN 2
#define M1_MAX_LEN 2
--
2.16.4