* [Qemu-devel] [PATCH for-2.8 v2 2/3] module: Don't load the same module if requested multiple times
2016-08-16 7:59 [Qemu-devel] [PATCH for-2.8 v2 0/3] block: Fix libbz2 library dependency regresssion Fam Zheng
2016-08-16 7:59 ` [Qemu-devel] [PATCH for-2.8 v2 1/3] scripts: Allow block module to not define BlockDriver Fam Zheng
@ 2016-08-16 7:59 ` Fam Zheng
2016-08-16 7:59 ` [Qemu-devel] [PATCH for-2.8 v2 3/3] dmg: Move libbz2 code to dmg-bz2.so Fam Zheng
2 siblings, 0 replies; 5+ messages in thread
From: Fam Zheng @ 2016-08-16 7:59 UTC (permalink / raw)
To: qemu-devel; +Cc: Stefan Hajnoczi, Kevin Wolf, qemu-block, Max Reitz
Use a hash table to keep record of all loaded modules, and return early
if the requested module is already loaded.
Signed-off-by: Fam Zheng <famz@redhat.com>
---
util/module.c | 19 +++++++++++++++++--
1 file changed, 17 insertions(+), 2 deletions(-)
diff --git a/util/module.c b/util/module.c
index a5f7fbd..63efad6 100644
--- a/util/module.c
+++ b/util/module.c
@@ -163,14 +163,29 @@ void module_load_one(const char *prefix, const char *lib_name)
char *fname = NULL;
char *exec_dir;
char *dirs[3];
+ char *module_name;
int i = 0;
int ret;
+ static GHashTable *loaded_modules;
if (!g_module_supported()) {
fprintf(stderr, "Module is not supported by system.\n");
return;
}
+ if (!loaded_modules) {
+ loaded_modules = g_hash_table_new(g_str_hash, g_str_equal);
+ }
+
+ module_name = g_strdup_printf("%s%s", prefix, lib_name);
+
+ if (g_hash_table_lookup(loaded_modules, module_name)) {
+ fprintf(stderr, "module is already loaded: %s\n", module_name);
+ g_free(module_name);
+ return;
+ }
+ g_hash_table_insert(loaded_modules, module_name, module_name);
+
exec_dir = qemu_get_exec_dir();
dirs[i++] = g_strdup_printf("%s", CONFIG_QEMU_MODDIR);
dirs[i++] = g_strdup_printf("%s/..", exec_dir ? : "");
@@ -180,8 +195,8 @@ void module_load_one(const char *prefix, const char *lib_name)
exec_dir = NULL;
for (i = 0; i < ARRAY_SIZE(dirs); i++) {
- fname = g_strdup_printf("%s/%s%s%s",
- dirs[i], prefix, lib_name, HOST_DSOSUF);
+ fname = g_strdup_printf("%s/%s%s",
+ dirs[i], module_name, HOST_DSOSUF);
ret = module_load_file(fname);
g_free(fname);
fname = NULL;
--
2.7.4
^ permalink raw reply related [flat|nested] 5+ messages in thread* [Qemu-devel] [PATCH for-2.8 v2 3/3] dmg: Move libbz2 code to dmg-bz2.so
2016-08-16 7:59 [Qemu-devel] [PATCH for-2.8 v2 0/3] block: Fix libbz2 library dependency regresssion Fam Zheng
2016-08-16 7:59 ` [Qemu-devel] [PATCH for-2.8 v2 1/3] scripts: Allow block module to not define BlockDriver Fam Zheng
2016-08-16 7:59 ` [Qemu-devel] [PATCH for-2.8 v2 2/3] module: Don't load the same module if requested multiple times Fam Zheng
@ 2016-08-16 7:59 ` Fam Zheng
2016-08-16 8:02 ` Fam Zheng
2 siblings, 1 reply; 5+ messages in thread
From: Fam Zheng @ 2016-08-16 7:59 UTC (permalink / raw)
To: qemu-devel; +Cc: Stefan Hajnoczi, Kevin Wolf, qemu-block, Max Reitz
dmg.o was moved to block-obj-m in 5505e8b76 to become a separate module,
so that its reference to libbz2, since 6b383c08c, doesn't add an extra
library to the main executable.
Until recently, commit 06e60f70a (blockdev: Add dynamic module loading
for block drivers) moved it back to block-obj-y to simplify the design
of dynamic loading of block modules. But we don't want to lose the
feature of less library dependency on the main executable.
The solution here is to move only the bz2 related code to a separate
DSO file, and load it when dmg_open is called.
dmg_probe doesn't depend on bz2 support to work, and is the only code in
this file which can run before dmg_open.
Signed-off-by: Fam Zheng <famz@redhat.com>
---
block/Makefile.objs | 3 ++-
block/dmg-bz2.c | 62 +++++++++++++++++++++++++++++++++++++++++++++++
block/dmg.c | 69 +++++++++++++----------------------------------------
block/dmg.h | 59 +++++++++++++++++++++++++++++++++++++++++++++
4 files changed, 140 insertions(+), 53 deletions(-)
create mode 100644 block/dmg-bz2.c
create mode 100644 block/dmg.h
diff --git a/block/Makefile.objs b/block/Makefile.objs
index fa4d8b8..141dec5 100644
--- a/block/Makefile.objs
+++ b/block/Makefile.objs
@@ -40,6 +40,7 @@ gluster.o-libs := $(GLUSTERFS_LIBS)
ssh.o-cflags := $(LIBSSH2_CFLAGS)
ssh.o-libs := $(LIBSSH2_LIBS)
archipelago.o-libs := $(ARCHIPELAGO_LIBS)
-dmg.o-libs := $(BZIP2_LIBS)
+block-obj-$(if $(CONFIG_BZIP2),m,n) += dmg-bz2.o
+dmg-bz2.o-libs := $(BZIP2_LIBS)
qcow.o-libs := -lz
linux-aio.o-libs := -laio
diff --git a/block/dmg-bz2.c b/block/dmg-bz2.c
new file mode 100644
index 0000000..a60e398
--- /dev/null
+++ b/block/dmg-bz2.c
@@ -0,0 +1,62 @@
+/*
+ * DMG bzip2 uncompression
+ *
+ * Copyright (c) 2004 Johannes E. Schindelin
+ * Copyright (c) 2016 Red Hat, Int.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+#include "qemu/osdep.h"
+#include "qemu-common.h"
+#include "dmg.h"
+#include <bzlib.h>
+
+static int dmg_uncompress_bz2_do(char *next_in, unsigned int avail_in,
+ char *next_out, unsigned int avail_out)
+{
+ int ret;
+ uint64_t total_out;
+ bz_stream bzstream = {};
+
+ ret = BZ2_bzDecompressInit(&bzstream, 0, 0);
+ if (ret != BZ_OK) {
+ return -1;
+ }
+ bzstream.next_in = next_in;
+ bzstream.avail_in = avail_in;
+ bzstream.next_out = next_out;
+ bzstream.avail_out = avail_out;
+ ret = BZ2_bzDecompress(&bzstream);
+ total_out = ((uint64_t)bzstream.total_out_hi32 << 32) +
+ bzstream.total_out_lo32;
+ BZ2_bzDecompressEnd(&bzstream);
+ if (ret != BZ_STREAM_END ||
+ total_out != avail_out) {
+ return -1;
+ }
+ return 0;
+}
+
+__attribute__((constructor))
+static void dmg_bz2_init(void)
+{
+ assert(!dmg_uncompress_bz2);
+ dmg_uncompress_bz2 = dmg_uncompress_bz2_do;
+}
+
diff --git a/block/dmg.c b/block/dmg.c
index b0ed89b..621bce0 100644
--- a/block/dmg.c
+++ b/block/dmg.c
@@ -28,10 +28,10 @@
#include "qemu/bswap.h"
#include "qemu/error-report.h"
#include "qemu/module.h"
-#include <zlib.h>
-#ifdef CONFIG_BZIP2
-#include <bzlib.h>
-#endif
+#include "dmg.h"
+
+int (*dmg_uncompress_bz2)(char *next_in, unsigned int avail_in,
+ char *next_out, unsigned int avail_out);
enum {
/* Limit chunk sizes to prevent unreasonable amounts of memory being used
@@ -41,31 +41,6 @@ enum {
DMG_SECTORCOUNTS_MAX = DMG_LENGTHS_MAX / 512,
};
-typedef struct BDRVDMGState {
- CoMutex lock;
- /* each chunk contains a certain number of sectors,
- * offsets[i] is the offset in the .dmg file,
- * lengths[i] is the length of the compressed chunk,
- * sectors[i] is the sector beginning at offsets[i],
- * sectorcounts[i] is the number of sectors in that chunk,
- * the sectors array is ordered
- * 0<=i<n_chunks */
-
- uint32_t n_chunks;
- uint32_t* types;
- uint64_t* offsets;
- uint64_t* lengths;
- uint64_t* sectors;
- uint64_t* sectorcounts;
- uint32_t current_chunk;
- uint8_t *compressed_chunk;
- uint8_t *uncompressed_chunk;
- z_stream zstream;
-#ifdef CONFIG_BZIP2
- bz_stream bzstream;
-#endif
-} BDRVDMGState;
-
static int dmg_probe(const uint8_t *buf, int buf_size, const char *filename)
{
int len;
@@ -210,10 +185,9 @@ static bool dmg_is_known_block_type(uint32_t entry_type)
case 0x00000001: /* uncompressed */
case 0x00000002: /* zeroes */
case 0x80000005: /* zlib */
-#ifdef CONFIG_BZIP2
- case 0x80000006: /* bzip2 */
-#endif
return true;
+ case 0x80000006: /* bzip2 */
+ return !!dmg_uncompress_bz2;
default:
return false;
}
@@ -439,6 +413,7 @@ static int dmg_open(BlockDriverState *bs, QDict *options, int flags,
int64_t offset;
int ret;
+ block_module_load_one("dmg-bz2");
bs->read_only = true;
s->n_chunks = 0;
@@ -587,9 +562,6 @@ static inline int dmg_read_chunk(BlockDriverState *bs, uint64_t sector_num)
if (!is_sector_in_chunk(s, s->current_chunk, sector_num)) {
int ret;
uint32_t chunk = search_chunk(s, sector_num);
-#ifdef CONFIG_BZIP2
- uint64_t total_out;
-#endif
if (chunk >= s->n_chunks) {
return -1;
@@ -620,8 +592,10 @@ static inline int dmg_read_chunk(BlockDriverState *bs, uint64_t sector_num)
return -1;
}
break; }
-#ifdef CONFIG_BZIP2
case 0x80000006: /* bzip2 compressed */
+ if (!dmg_uncompress_bz2) {
+ break;
+ }
/* we need to buffer, because only the chunk as whole can be
* inflated. */
ret = bdrv_pread(bs->file, s->offsets[chunk],
@@ -630,24 +604,15 @@ static inline int dmg_read_chunk(BlockDriverState *bs, uint64_t sector_num)
return -1;
}
- ret = BZ2_bzDecompressInit(&s->bzstream, 0, 0);
- if (ret != BZ_OK) {
- return -1;
- }
- s->bzstream.next_in = (char *)s->compressed_chunk;
- s->bzstream.avail_in = (unsigned int) s->lengths[chunk];
- s->bzstream.next_out = (char *)s->uncompressed_chunk;
- s->bzstream.avail_out = (unsigned int) 512 * s->sectorcounts[chunk];
- ret = BZ2_bzDecompress(&s->bzstream);
- total_out = ((uint64_t)s->bzstream.total_out_hi32 << 32) +
- s->bzstream.total_out_lo32;
- BZ2_bzDecompressEnd(&s->bzstream);
- if (ret != BZ_STREAM_END ||
- total_out != 512 * s->sectorcounts[chunk]) {
- return -1;
+ ret = dmg_uncompress_bz2((char *)s->compressed_chunk,
+ (unsigned int) s->lengths[chunk],
+ (char *)s->uncompressed_chunk,
+ (unsigned int)
+ 512 * s->sectorcounts[chunk]);
+ if (ret < 0) {
+ return ret;
}
break;
-#endif /* CONFIG_BZIP2 */
case 1: /* copy */
ret = bdrv_pread(bs->file, s->offsets[chunk],
s->uncompressed_chunk, s->lengths[chunk]);
diff --git a/block/dmg.h b/block/dmg.h
new file mode 100644
index 0000000..b592d6f
--- /dev/null
+++ b/block/dmg.h
@@ -0,0 +1,59 @@
+/*
+ * Header for DMG driver
+ *
+ * Copyright (c) 2004-2006 Fabrice Bellard
+ * Copyright (c) 2016 Red hat, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#ifndef BLOCK_DMG_H
+#define BLOCK_DMG_H
+
+#include "qemu/osdep.h"
+#include "qemu-common.h"
+#include "block/block_int.h"
+#include <zlib.h>
+
+typedef struct BDRVDMGState {
+ CoMutex lock;
+ /* each chunk contains a certain number of sectors,
+ * offsets[i] is the offset in the .dmg file,
+ * lengths[i] is the length of the compressed chunk,
+ * sectors[i] is the sector beginning at offsets[i],
+ * sectorcounts[i] is the number of sectors in that chunk,
+ * the sectors array is ordered
+ * 0<=i<n_chunks */
+
+ uint32_t n_chunks;
+ uint32_t *types;
+ uint64_t *offsets;
+ uint64_t *lengths;
+ uint64_t *sectors;
+ uint64_t *sectorcounts;
+ uint32_t current_chunk;
+ uint8_t *compressed_chunk;
+ uint8_t *uncompressed_chunk;
+ z_stream zstream;
+} BDRVDMGState;
+
+extern int (*dmg_uncompress_bz2)(char *next_in, unsigned int avail_in,
+ char *next_out, unsigned int avail_out);
+
+#endif
--
2.7.4
^ permalink raw reply related [flat|nested] 5+ messages in thread