Adds zstd support to the btrfs module.
Tested on Ubuntu-18.04 with a btrfs /boot partition with and without zstd
compression. A test case was also added to the test suite that fails before
the patch, and passes after.
Signed-off-by: Nick Terrell <terrelln@xxxxxx>
---
v1 -> v2:
- Fix comments from Daniel Kiper.
v2 -> v3:
- Use grub_error() to set grub_errno in grub_btrfs_zstd_decompress().
- Fix style and formatting comments.
Makefile.util.def | 10 +++-
grub-core/Makefile.core.def | 10 +++-
grub-core/fs/btrfs.c | 112 ++++++++++++++++++++++++++++++++++-
tests/btrfs_test.in | 1 +
tests/util/grub-fs-tester.in | 2 +-
5 files changed, 131 insertions(+), 4 deletions(-)
diff --git a/Makefile.util.def b/Makefile.util.def
index f9caccb97..27c5e9903 100644
--- a/Makefile.util.def
+++ b/Makefile.util.def
@@ -54,7 +54,7 @@ library = {
library = {
name = libgrubmods.a;
cflags = '-fno-builtin -Wno-undef';
- cppflags = '-I$(top_srcdir)/grub-core/lib/minilzo -I$(srcdir)/grub-core/lib/xzembed -DMINILZO_HAVE_CONFIG_H';
+ cppflags = '-I$(srcdir)/grub-core/lib/minilzo -I$(srcdir)/grub-core/lib/xzembed -I$(srcdir)/grub-core/lib/zstd -DMINILZO_HAVE_CONFIG_H';
common_nodist = grub_script.tab.c;
common_nodist = grub_script.yy.c;
@@ -164,6 +164,14 @@ library = {
common = grub-core/lib/xzembed/xz_dec_bcj.c;
common = grub-core/lib/xzembed/xz_dec_lzma2.c;
common = grub-core/lib/xzembed/xz_dec_stream.c;
+ common = grub-core/lib/zstd/debug.c;
+ common = grub-core/lib/zstd/entropy_common.c;
+ common = grub-core/lib/zstd/error_private.c;
+ common = grub-core/lib/zstd/fse_decompress.c;
+ common = grub-core/lib/zstd/huf_decompress.c;
+ common = grub-core/lib/zstd/xxhash.c;
+ common = grub-core/lib/zstd/zstd_common.c;
+ common = grub-core/lib/zstd/zstd_decompress.c;
};
program = {
diff --git a/grub-core/Makefile.core.def b/grub-core/Makefile.core.def
index 2c1d62cee..f818f58bc 100644
--- a/grub-core/Makefile.core.def
+++ b/grub-core/Makefile.core.def
@@ -1265,8 +1265,16 @@ module = {
name = btrfs;
common = fs/btrfs.c;
common = lib/crc.c;
+ common = lib/zstd/debug.c;
+ common = lib/zstd/entropy_common.c;
+ common = lib/zstd/error_private.c;
+ common = lib/zstd/fse_decompress.c;
+ common = lib/zstd/huf_decompress.c;
+ common = lib/zstd/xxhash.c;
+ common = lib/zstd/zstd_common.c;
+ common = lib/zstd/zstd_decompress.c;
cflags = '$(CFLAGS_POSIX) -Wno-undef';
- cppflags = '-I$(srcdir)/lib/posix_wrap -I$(srcdir)/lib/minilzo -DMINILZO_HAVE_CONFIG_H';
+ cppflags = '-I$(srcdir)/lib/posix_wrap -I$(srcdir)/lib/minilzo -I$(srcdir)/lib/zstd -DMINILZO_HAVE_CONFIG_H';
};
module = {
diff --git a/grub-core/fs/btrfs.c b/grub-core/fs/btrfs.c
index 4849c1ceb..c44fe8029 100644
--- a/grub-core/fs/btrfs.c
+++ b/grub-core/fs/btrfs.c
@@ -17,6 +17,8 @@
* along with GRUB. If not, see <http://www.gnu.org/licenses/>.
*/
+#define ZSTD_STATIC_LINKING_ONLY
+
#include <grub/err.h>
#include <grub/file.h>
#include <grub/mm.h>
@@ -27,6 +29,7 @@
#include <grub/lib/crc.h>
#include <grub/deflate.h>
#include <minilzo.h>
+#include <zstd.h>
#include <grub/i18n.h>
#include <grub/btrfs.h>
@@ -45,6 +48,9 @@ GRUB_MOD_LICENSE ("GPLv3+");
#define GRUB_BTRFS_LZO_BLOCK_MAX_CSIZE (GRUB_BTRFS_LZO_BLOCK_SIZE + \
(GRUB_BTRFS_LZO_BLOCK_SIZE / 16) + 64 + 3)
+#define ZSTD_BTRFS_MAX_WINDOWLOG 17
+#define ZSTD_BTRFS_MAX_INPUT (1 << ZSTD_BTRFS_MAX_WINDOWLOG)
+
typedef grub_uint8_t grub_btrfs_checksum_t[0x20];
typedef grub_uint16_t grub_btrfs_uuid_t[8];
@@ -212,6 +218,7 @@ struct grub_btrfs_extent_data
#define GRUB_BTRFS_COMPRESSION_NONE 0
#define GRUB_BTRFS_COMPRESSION_ZLIB 1
#define GRUB_BTRFS_COMPRESSION_LZO 2
+#define GRUB_BTRFS_COMPRESSION_ZSTD 3
#define GRUB_BTRFS_OBJECT_ID_CHUNK 0x100
@@ -912,6 +919,95 @@ grub_btrfs_read_inode (struct grub_btrfs_data *data,
return grub_btrfs_read_logical (data, elemaddr, inode, sizeof (*inode), 0);
}
+static void* grub_zstd_malloc (void* state, size_t size)
+{
+ (void)state;
+
+ return grub_malloc (size);
+}
+
+static void grub_zstd_free (void* state, void* address)
+{
+ (void)state;
+
+ return grub_free (address);
+}
+
+static ZSTD_customMem grub_zstd_allocator (void)
+{
+ ZSTD_customMem allocator;
+
+ allocator.customAlloc = &grub_zstd_malloc;
+ allocator.customFree = &grub_zstd_free;
+ allocator.opaque = NULL;
+
+ return allocator;
+}
+
+static grub_ssize_t
+grub_btrfs_zstd_decompress (char *ibuf, grub_size_t isize, grub_off_t off,
+ char *obuf, grub_size_t osize)
+{
+ void *allocated = NULL;
+ char *otmpbuf = obuf;
+ grub_size_t otmpsize = osize;
+ ZSTD_DCtx *dctx = NULL;
+ grub_size_t zstd_ret;
+ grub_ssize_t ret = -1;
+
+ /*
+ * Zstd will fail if it can't fit the entire output in the destination
+ * buffer, so if osize isn't large enough, allocate a temporary buffer.
+ */
+ if (otmpsize < ZSTD_BTRFS_MAX_INPUT) {
+ allocated = grub_malloc (ZSTD_BTRFS_MAX_INPUT);
+ if (!allocated) {
+ goto err;
+ }
+ otmpbuf = (char*)allocated;
+ otmpsize = ZSTD_BTRFS_MAX_INPUT;
+ }
+
+ /* Create the ZSTD_DCtx. */
+ dctx = ZSTD_createDCtx_advanced (grub_zstd_allocator ());
+ if (!dctx) {
+ grub_error (GRUB_ERR_OUT_OF_MEMORY, "zstd out of memory");
+ goto err;
+ }
+
+ /*
+ * Get the real input size, there may be junk at the
+ * end of the frame.
+ */
+ isize = ZSTD_findFrameCompressedSize (ibuf, isize);
+ if (ZSTD_isError (isize)) {
+ grub_error (GRUB_ERR_BAD_COMPRESSED_DATA,
+ "zstd data corrupted");
+ goto err;
+ }
+
+ /* Decompress and check for errors. */
+ zstd_ret = ZSTD_decompressDCtx (dctx, otmpbuf, otmpsize, ibuf, isize);
+ if (ZSTD_isError (zstd_ret)) {
+ grub_error (GRUB_ERR_BAD_COMPRESSED_DATA,
+ "zstd data corrupted");
+ goto err;
+ }
+
+ /*
+ * Move the requested data into the obuf. obuf may be equal
+ * to otmpbuf, which is why grub_memmove() is required.
+ */
+ grub_memmove (obuf, otmpbuf + off, osize);
+ ret = osize;
+
+err:
+ grub_free (allocated);
+ ZSTD_freeDCtx (dctx);
+
+ return ret;
+}
+
static grub_ssize_t
grub_btrfs_lzo_decompress(char *ibuf, grub_size_t isize, grub_off_t off,
char *obuf, grub_size_t osize)
@@ -1087,7 +1183,8 @@ grub_btrfs_extent_read (struct grub_btrfs_data *data,
if (data->extent->compression != GRUB_BTRFS_COMPRESSION_NONE
&& data->extent->compression != GRUB_BTRFS_COMPRESSION_ZLIB
- && data->extent->compression != GRUB_BTRFS_COMPRESSION_LZO)
+ && data->extent->compression != GRUB_BTRFS_COMPRESSION_LZO
+ && data->extent->compression != GRUB_BTRFS_COMPRESSION_ZSTD)
{
grub_error (GRUB_ERR_NOT_IMPLEMENTED_YET,
"compression type 0x%x not supported",
@@ -1127,6 +1224,15 @@ grub_btrfs_extent_read (struct grub_btrfs_data *data,
!= (grub_ssize_t) csize)
return -1;
}
+ else if (data->extent->compression == GRUB_BTRFS_COMPRESSION_ZSTD)
+ {
+ if (grub_btrfs_zstd_decompress(data->extent->inl, data->extsize -
+ ((grub_uint8_t *) data->extent->inl
+ - (grub_uint8_t *) data->extent),
+ extoff, buf, csize)
+ != (grub_ssize_t) csize)
+ return -1;
+ }
else
grub_memcpy (buf, data->extent->inl + extoff, csize);
break;
@@ -1164,6 +1270,10 @@ grub_btrfs_extent_read (struct grub_btrfs_data *data,
ret = grub_btrfs_lzo_decompress (tmp, zsize, extoff
+ grub_le_to_cpu64 (data->extent->offset),
buf, csize);
+ else if (data->extent->compression == GRUB_BTRFS_COMPRESSION_ZSTD)
+ ret = grub_btrfs_zstd_decompress (tmp, zsize, extoff
+ + grub_le_to_cpu64 (data->extent->offset),
+ buf, csize);
else
ret = -1;
diff --git a/tests/btrfs_test.in b/tests/btrfs_test.in
index 2b37ddd33..0c9bf3a68 100644
--- a/tests/btrfs_test.in
+++ b/tests/btrfs_test.in
@@ -18,6 +18,7 @@ fi
"@builddir@/grub-fs-tester" btrfs
"@builddir@/grub-fs-tester" btrfs_zlib
"@builddir@/grub-fs-tester" btrfs_lzo
+"@builddir@/grub-fs-tester" btrfs_zstd
"@builddir@/grub-fs-tester" btrfs_raid0
"@builddir@/grub-fs-tester" btrfs_raid1
"@builddir@/grub-fs-tester" btrfs_single
diff --git a/tests/util/grub-fs-tester.in b/tests/util/grub-fs-tester.in
index 15969d796..3470c89e3 100644
--- a/tests/util/grub-fs-tester.in
+++ b/tests/util/grub-fs-tester.in
@@ -626,7 +626,7 @@ for LOGSECSIZE in $(range "$MINLOGSECSIZE" "$MAXLOGSECSIZE" 1); do
;;
x"btrfs")
"mkfs.btrfs" -s $SECSIZE -L "$FSLABEL" "${MOUNTDEVICE}" ;;
- x"btrfs_zlib" | x"btrfs_lzo")
+ x"btrfs_zlib" | x"btrfs_lzo" | x"btrfs_zstd")
"mkfs.btrfs" -s $SECSIZE -L "$FSLABEL" "${MOUNTDEVICE}"
MOUNTOPTS="compress=${fs/btrfs_/},"
MOUNTFS="btrfs"
--
2.17.1
