pstore: add lzo/lz4 compression support

Like zlib compression in pstore, this patch added lzo and lz4
compression support so that users can have more options and better
compression ratio.

The original code treats the compressed data together with the
uncompressed ECC correction notice by using zlib decompress. The
ECC correction notice is missing in the decompression process. The
treatment also makes lzo and lz4 not working. So I treat them
separately by using pstore_decompress() to treat the compressed
data, and memcpy() to treat the uncompressed ECC correction notice.

Signed-off-by: Geliang Tang <geliangtang@163.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
This commit is contained in:
Geliang Tang 2016-02-18 22:04:22 +08:00 committed by Kees Cook
parent 235f6d157d
commit 8cfc8ddc99
7 changed files with 261 additions and 18 deletions

View File

@ -444,7 +444,8 @@ static int nvram_pstore_write(enum pstore_type_id type,
*/
static ssize_t nvram_pstore_read(u64 *id, enum pstore_type_id *type,
int *count, struct timespec *time, char **buf,
bool *compressed, struct pstore_info *psi)
bool *compressed, ssize_t *ecc_notice_size,
struct pstore_info *psi)
{
struct oops_log_info *oops_hdr;
unsigned int err_type, id_no, size = 0;
@ -545,6 +546,7 @@ static ssize_t nvram_pstore_read(u64 *id, enum pstore_type_id *type,
return -ENOMEM;
kfree(buff);
*ecc_notice_size = 0;
if (err_type == ERR_TYPE_KERNEL_PANIC_GZ)
*compressed = true;
else

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@ -927,7 +927,8 @@ static int erst_open_pstore(struct pstore_info *psi);
static int erst_close_pstore(struct pstore_info *psi);
static ssize_t erst_reader(u64 *id, enum pstore_type_id *type, int *count,
struct timespec *time, char **buf,
bool *compressed, struct pstore_info *psi);
bool *compressed, ssize_t *ecc_notice_size,
struct pstore_info *psi);
static int erst_writer(enum pstore_type_id type, enum kmsg_dump_reason reason,
u64 *id, unsigned int part, int count, bool compressed,
size_t size, struct pstore_info *psi);
@ -987,7 +988,8 @@ static int erst_close_pstore(struct pstore_info *psi)
static ssize_t erst_reader(u64 *id, enum pstore_type_id *type, int *count,
struct timespec *time, char **buf,
bool *compressed, struct pstore_info *psi)
bool *compressed, ssize_t *ecc_notice_size,
struct pstore_info *psi)
{
int rc;
ssize_t len = 0;
@ -1033,6 +1035,7 @@ static ssize_t erst_reader(u64 *id, enum pstore_type_id *type, int *count,
memcpy(*buf, rcd->data, len - sizeof(*rcd));
*id = record_id;
*compressed = false;
*ecc_notice_size = 0;
if (uuid_le_cmp(rcd->sec_hdr.section_type,
CPER_SECTION_TYPE_DMESG_Z) == 0) {
*type = PSTORE_TYPE_DMESG;

View File

@ -34,6 +34,7 @@ struct pstore_read_data {
int *count;
struct timespec *timespec;
bool *compressed;
ssize_t *ecc_notice_size;
char **buf;
};
@ -69,6 +70,7 @@ static int efi_pstore_read_func(struct efivar_entry *entry, void *data)
*cb_data->compressed = true;
else
*cb_data->compressed = false;
*cb_data->ecc_notice_size = 0;
} else if (sscanf(name, "dump-type%u-%u-%d-%lu",
cb_data->type, &part, &cnt, &time) == 4) {
*cb_data->id = generic_id(time, part, cnt);
@ -76,6 +78,7 @@ static int efi_pstore_read_func(struct efivar_entry *entry, void *data)
cb_data->timespec->tv_sec = time;
cb_data->timespec->tv_nsec = 0;
*cb_data->compressed = false;
*cb_data->ecc_notice_size = 0;
} else if (sscanf(name, "dump-type%u-%u-%lu",
cb_data->type, &part, &time) == 3) {
/*
@ -88,6 +91,7 @@ static int efi_pstore_read_func(struct efivar_entry *entry, void *data)
cb_data->timespec->tv_sec = time;
cb_data->timespec->tv_nsec = 0;
*cb_data->compressed = false;
*cb_data->ecc_notice_size = 0;
} else
return 0;
@ -210,6 +214,7 @@ static int efi_pstore_sysfs_entry_iter(void *data, struct efivar_entry **pos)
static ssize_t efi_pstore_read(u64 *id, enum pstore_type_id *type,
int *count, struct timespec *timespec,
char **buf, bool *compressed,
ssize_t *ecc_notice_size,
struct pstore_info *psi)
{
struct pstore_read_data data;
@ -220,6 +225,7 @@ static ssize_t efi_pstore_read(u64 *id, enum pstore_type_id *type,
data.count = count;
data.timespec = timespec;
data.compressed = compressed;
data.ecc_notice_size = ecc_notice_size;
data.buf = buf;
*data.buf = kzalloc(EFIVARS_DATA_SIZE_MAX, GFP_KERNEL);

View File

@ -1,8 +1,6 @@
config PSTORE
tristate "Persistent store support"
default n
select ZLIB_DEFLATE
select ZLIB_INFLATE
help
This option enables generic access to platform level
persistent storage via "pstore" filesystem that can
@ -14,6 +12,35 @@ config PSTORE
If you don't have a platform persistent store driver,
say N.
choice
prompt "Choose compression algorithm"
depends on PSTORE
default PSTORE_ZLIB_COMPRESS
help
This option chooses compression algorithm.
config PSTORE_ZLIB_COMPRESS
bool "ZLIB"
select ZLIB_DEFLATE
select ZLIB_INFLATE
help
This option enables ZLIB compression algorithm support.
config PSTORE_LZO_COMPRESS
bool "LZO"
select LZO_COMPRESS
select LZO_DECOMPRESS
help
This option enables LZO compression algorithm support.
config PSTORE_LZ4_COMPRESS
bool "LZ4"
select LZ4_COMPRESS
select LZ4_DECOMPRESS
help
This option enables LZ4 compression algorithm support.
endchoice
config PSTORE_CONSOLE
bool "Log kernel console messages"
depends on PSTORE

View File

@ -28,7 +28,15 @@
#include <linux/console.h>
#include <linux/module.h>
#include <linux/pstore.h>
#ifdef CONFIG_PSTORE_ZLIB_COMPRESS
#include <linux/zlib.h>
#endif
#ifdef CONFIG_PSTORE_LZO_COMPRESS
#include <linux/lzo.h>
#endif
#ifdef CONFIG_PSTORE_LZ4_COMPRESS
#include <linux/lz4.h>
#endif
#include <linux/string.h>
#include <linux/timer.h>
#include <linux/slab.h>
@ -69,10 +77,23 @@ struct pstore_info *psinfo;
static char *backend;
/* Compression parameters */
#ifdef CONFIG_PSTORE_ZLIB_COMPRESS
#define COMPR_LEVEL 6
#define WINDOW_BITS 12
#define MEM_LEVEL 4
static struct z_stream_s stream;
#else
static unsigned char *workspace;
#endif
struct pstore_zbackend {
int (*compress)(const void *in, void *out, size_t inlen, size_t outlen);
int (*decompress)(void *in, void *out, size_t inlen, size_t outlen);
void (*allocate)(void);
void (*free)(void);
const char *name;
};
static char *big_oops_buf;
static size_t big_oops_buf_sz;
@ -129,9 +150,9 @@ bool pstore_cannot_block_path(enum kmsg_dump_reason reason)
}
EXPORT_SYMBOL_GPL(pstore_cannot_block_path);
#ifdef CONFIG_PSTORE_ZLIB_COMPRESS
/* Derived from logfs_compress() */
static int pstore_compress(const void *in, void *out, size_t inlen,
size_t outlen)
static int compress_zlib(const void *in, void *out, size_t inlen, size_t outlen)
{
int err, ret;
@ -165,7 +186,7 @@ static int pstore_compress(const void *in, void *out, size_t inlen,
}
/* Derived from logfs_uncompress */
static int pstore_decompress(void *in, void *out, size_t inlen, size_t outlen)
static int decompress_zlib(void *in, void *out, size_t inlen, size_t outlen)
{
int err, ret;
@ -194,7 +215,7 @@ static int pstore_decompress(void *in, void *out, size_t inlen, size_t outlen)
return ret;
}
static void allocate_buf_for_compression(void)
static void allocate_zlib(void)
{
size_t size;
size_t cmpr;
@ -237,12 +258,190 @@ static void allocate_buf_for_compression(void)
}
static void free_buf_for_compression(void)
static void free_zlib(void)
{
kfree(stream.workspace);
stream.workspace = NULL;
kfree(big_oops_buf);
big_oops_buf = NULL;
big_oops_buf_sz = 0;
}
static struct pstore_zbackend backend_zlib = {
.compress = compress_zlib,
.decompress = decompress_zlib,
.allocate = allocate_zlib,
.free = free_zlib,
.name = "zlib",
};
#endif
#ifdef CONFIG_PSTORE_LZO_COMPRESS
static int compress_lzo(const void *in, void *out, size_t inlen, size_t outlen)
{
int ret;
ret = lzo1x_1_compress(in, inlen, out, &outlen, workspace);
if (ret != LZO_E_OK) {
pr_err("lzo_compress error, ret = %d!\n", ret);
return -EIO;
}
return outlen;
}
static int decompress_lzo(void *in, void *out, size_t inlen, size_t outlen)
{
int ret;
ret = lzo1x_decompress_safe(in, inlen, out, &outlen);
if (ret != LZO_E_OK) {
pr_err("lzo_decompress error, ret = %d!\n", ret);
return -EIO;
}
return outlen;
}
static void allocate_lzo(void)
{
big_oops_buf_sz = lzo1x_worst_compress(psinfo->bufsize);
big_oops_buf = kmalloc(big_oops_buf_sz, GFP_KERNEL);
if (big_oops_buf) {
workspace = kmalloc(LZO1X_MEM_COMPRESS, GFP_KERNEL);
if (!workspace) {
pr_err("No memory for compression workspace; skipping compression\n");
kfree(big_oops_buf);
big_oops_buf = NULL;
}
} else {
pr_err("No memory for uncompressed data; skipping compression\n");
workspace = NULL;
}
}
static void free_lzo(void)
{
kfree(workspace);
kfree(big_oops_buf);
big_oops_buf = NULL;
big_oops_buf_sz = 0;
}
static struct pstore_zbackend backend_lzo = {
.compress = compress_lzo,
.decompress = decompress_lzo,
.allocate = allocate_lzo,
.free = free_lzo,
.name = "lzo",
};
#endif
#ifdef CONFIG_PSTORE_LZ4_COMPRESS
static int compress_lz4(const void *in, void *out, size_t inlen, size_t outlen)
{
int ret;
ret = lz4_compress(in, inlen, out, &outlen, workspace);
if (ret) {
pr_err("lz4_compress error, ret = %d!\n", ret);
return -EIO;
}
return outlen;
}
static int decompress_lz4(void *in, void *out, size_t inlen, size_t outlen)
{
int ret;
ret = lz4_decompress_unknownoutputsize(in, inlen, out, &outlen);
if (ret) {
pr_err("lz4_decompress error, ret = %d!\n", ret);
return -EIO;
}
return outlen;
}
static void allocate_lz4(void)
{
big_oops_buf_sz = lz4_compressbound(psinfo->bufsize);
big_oops_buf = kmalloc(big_oops_buf_sz, GFP_KERNEL);
if (big_oops_buf) {
workspace = kmalloc(LZ4_MEM_COMPRESS, GFP_KERNEL);
if (!workspace) {
pr_err("No memory for compression workspace; skipping compression\n");
kfree(big_oops_buf);
big_oops_buf = NULL;
}
} else {
pr_err("No memory for uncompressed data; skipping compression\n");
workspace = NULL;
}
}
static void free_lz4(void)
{
kfree(workspace);
kfree(big_oops_buf);
big_oops_buf = NULL;
big_oops_buf_sz = 0;
}
static struct pstore_zbackend backend_lz4 = {
.compress = compress_lz4,
.decompress = decompress_lz4,
.allocate = allocate_lz4,
.free = free_lz4,
.name = "lz4",
};
#endif
static struct pstore_zbackend *zbackend =
#if defined(CONFIG_PSTORE_ZLIB_COMPRESS)
&backend_zlib;
#elif defined(CONFIG_PSTORE_LZO_COMPRESS)
&backend_lzo;
#elif defined(CONFIG_PSTORE_LZ4_COMPRESS)
&backend_lz4;
#else
NULL;
#endif
static int pstore_compress(const void *in, void *out,
size_t inlen, size_t outlen)
{
if (zbackend)
return zbackend->compress(in, out, inlen, outlen);
else
return -EIO;
}
static int pstore_decompress(void *in, void *out, size_t inlen, size_t outlen)
{
if (zbackend)
return zbackend->decompress(in, out, inlen, outlen);
else
return -EIO;
}
static void allocate_buf_for_compression(void)
{
if (zbackend) {
pr_info("using %s compression\n", zbackend->name);
zbackend->allocate();
} else {
pr_err("allocate compression buffer error!\n");
}
}
static void free_buf_for_compression(void)
{
if (zbackend)
zbackend->free();
else
pr_err("free compression buffer error!\n");
}
/*
@ -522,6 +721,7 @@ void pstore_get_records(int quiet)
int failed = 0, rc;
bool compressed;
int unzipped_len = -1;
ssize_t ecc_notice_size = 0;
if (!psi)
return;
@ -531,7 +731,7 @@ void pstore_get_records(int quiet)
goto out;
while ((size = psi->read(&id, &type, &count, &time, &buf, &compressed,
psi)) > 0) {
&ecc_notice_size, psi)) > 0) {
if (compressed && (type == PSTORE_TYPE_DMESG)) {
if (big_oops_buf)
unzipped_len = pstore_decompress(buf,
@ -539,6 +739,9 @@ void pstore_get_records(int quiet)
big_oops_buf_sz);
if (unzipped_len > 0) {
if (ecc_notice_size)
memcpy(big_oops_buf + unzipped_len,
buf + size, ecc_notice_size);
kfree(buf);
buf = big_oops_buf;
size = unzipped_len;
@ -550,7 +753,8 @@ void pstore_get_records(int quiet)
}
}
rc = pstore_mkfile(type, psi->name, id, count, buf,
compressed, (size_t)size, time, psi);
compressed, size + ecc_notice_size,
time, psi);
if (unzipped_len < 0) {
/* Free buffer other than big oops */
kfree(buf);

View File

@ -181,10 +181,10 @@ static bool prz_ok(struct persistent_ram_zone *prz)
static ssize_t ramoops_pstore_read(u64 *id, enum pstore_type_id *type,
int *count, struct timespec *time,
char **buf, bool *compressed,
ssize_t *ecc_notice_size,
struct pstore_info *psi)
{
ssize_t size;
ssize_t ecc_notice_size;
struct ramoops_context *cxt = psi->data;
struct persistent_ram_zone *prz = NULL;
int header_length = 0;
@ -229,16 +229,16 @@ static ssize_t ramoops_pstore_read(u64 *id, enum pstore_type_id *type,
size = persistent_ram_old_size(prz) - header_length;
/* ECC correction notice */
ecc_notice_size = persistent_ram_ecc_string(prz, NULL, 0);
*ecc_notice_size = persistent_ram_ecc_string(prz, NULL, 0);
*buf = kmalloc(size + ecc_notice_size + 1, GFP_KERNEL);
*buf = kmalloc(size + *ecc_notice_size + 1, GFP_KERNEL);
if (*buf == NULL)
return -ENOMEM;
memcpy(*buf, (char *)persistent_ram_old(prz) + header_length, size);
persistent_ram_ecc_string(prz, *buf + size, ecc_notice_size + 1);
persistent_ram_ecc_string(prz, *buf + size, *ecc_notice_size + 1);
return size + ecc_notice_size;
return size;
}
static size_t ramoops_write_kmsg_hdr(struct persistent_ram_zone *prz,

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@ -58,7 +58,8 @@ struct pstore_info {
int (*close)(struct pstore_info *psi);
ssize_t (*read)(u64 *id, enum pstore_type_id *type,
int *count, struct timespec *time, char **buf,
bool *compressed, struct pstore_info *psi);
bool *compressed, ssize_t *ecc_notice_size,
struct pstore_info *psi);
int (*write)(enum pstore_type_id type,
enum kmsg_dump_reason reason, u64 *id,
unsigned int part, int count, bool compressed,