[lvm-devel] main - libdm: symbol versioning with -flto
Zdenek Kabelac
zkabelac at sourceware.org
Tue Apr 6 20:07:15 UTC 2021
Gitweb: https://sourceware.org/git/?p=lvm2.git;a=commitdiff;h=a8480f0f6e2585a66fb0a9e25135fde8fb11d997
Commit: a8480f0f6e2585a66fb0a9e25135fde8fb11d997
Parent: 12949ea886259ead84597a1d4de37c8715d8edb7
Author: Zdenek Kabelac <zkabelac at redhat.com>
AuthorDate: Sat Apr 3 21:49:37 2021 +0200
Committer: Zdenek Kabelac <zkabelac at redhat.com>
CommitterDate: Tue Apr 6 21:26:57 2021 +0200
libdm: symbol versioning with -flto
Gcc10 introduced different strategy how to build
shared libraries with their new LTO optimizer.
Insired by:
https://akkadia.org/drepper/symbol-versioning
https://sourceware.org/pipermail/elfutils-devel/attachments/20200414/1c0c2903/attachment.bin
https://github.com/InBetweenNames/gentooLTO/issues/459
https://github.com/linux-rdma/rdma-core/blob/master/util/symver.h
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=48200
---
libdm/datastruct/bitset.c | 2 +-
libdm/ioctl/libdm-iface.c | 5 +++--
libdm/libdm-deptree.c | 23 ++++++++++++-----------
libdm/libdm-stats.c | 15 +++++++++------
libdm/misc/dmlib.h | 27 ++++++++++++++++++++++-----
5 files changed, 47 insertions(+), 25 deletions(-)
diff --git a/libdm/datastruct/bitset.c b/libdm/datastruct/bitset.c
index 8f36ec715..220ea2f26 100644
--- a/libdm/datastruct/bitset.c
+++ b/libdm/datastruct/bitset.c
@@ -247,11 +247,11 @@ bad:
* Maintain backward compatibility with older versions that did not
* accept a 'min_num_bits' argument to dm_bitset_parse_list().
*/
+DM_EXPORT_SYMBOL(dm_bitset_parse_list, 1_02_129)
dm_bitset_t dm_bitset_parse_list_v1_02_129(const char *str, struct dm_pool *mem);
dm_bitset_t dm_bitset_parse_list_v1_02_129(const char *str, struct dm_pool *mem)
{
return dm_bitset_parse_list(str, mem, 0);
}
-DM_EXPORT_SYMBOL(dm_bitset_parse_list, 1_02_129);
#endif
diff --git a/libdm/ioctl/libdm-iface.c b/libdm/ioctl/libdm-iface.c
index e459db88d..5b17614e6 100644
--- a/libdm/ioctl/libdm-iface.c
+++ b/libdm/ioctl/libdm-iface.c
@@ -709,7 +709,8 @@ int dm_format_dev(char *buf, int bufsize, uint32_t dev_major,
return 1;
}
-int dm_task_get_info(struct dm_task *dmt, struct dm_info *info)
+DM_EXPORT_NEW_SYMBOL(int, dm_task_get_info, 1_02_97)
+ (struct dm_task *dmt, struct dm_info *info)
{
if (!dmt->dmi.v4)
return 0;
@@ -2210,8 +2211,8 @@ void dm_lib_exit(void)
* no code in this file accidentally calls it.
*/
+DM_EXPORT_SYMBOL_BASE(dm_task_get_info)
int dm_task_get_info_base(struct dm_task *dmt, struct dm_info *info);
-DM_EXPORT_SYMBOL_BASE(dm_task_get_info);
int dm_task_get_info_base(struct dm_task *dmt, struct dm_info *info)
{
struct dm_info new_info;
diff --git a/libdm/libdm-deptree.c b/libdm/libdm-deptree.c
index e4cb6e5c0..06ebdc0c0 100644
--- a/libdm/libdm-deptree.c
+++ b/libdm/libdm-deptree.c
@@ -3311,15 +3311,16 @@ int dm_tree_node_add_raid_target_with_params_v2(struct dm_tree_node *node,
return 1;
}
-int dm_tree_node_add_cache_target(struct dm_tree_node *node,
- uint64_t size,
- uint64_t feature_flags, /* DM_CACHE_FEATURE_* */
- const char *metadata_uuid,
- const char *data_uuid,
- const char *origin_uuid,
- const char *policy_name,
- const struct dm_config_node *policy_settings,
- uint32_t data_block_size)
+DM_EXPORT_NEW_SYMBOL(int, dm_tree_node_add_cache_target, 1_02_138)
+ (struct dm_tree_node *node,
+ uint64_t size,
+ uint64_t feature_flags, /* DM_CACHE_FEATURE_* */
+ const char *metadata_uuid,
+ const char *data_uuid,
+ const char *origin_uuid,
+ const char *policy_name,
+ const struct dm_config_node *policy_settings,
+ uint32_t data_block_size)
{
struct dm_config_node *cn;
struct load_segment *seg;
@@ -3858,8 +3859,8 @@ void dm_tree_node_set_callback(struct dm_tree_node *dnode,
*/
/* Backward compatible dm_tree_node_size_changed() implementations. */
+DM_EXPORT_SYMBOL_BASE(dm_tree_node_size_changed)
int dm_tree_node_size_changed_base(const struct dm_tree_node *dnode);
-DM_EXPORT_SYMBOL_BASE(dm_tree_node_size_changed);
int dm_tree_node_size_changed_base(const struct dm_tree_node *dnode)
{
/* Base does not make difference between smaller and bigger */
@@ -3874,6 +3875,7 @@ int dm_tree_node_size_changed_base(const struct dm_tree_node *dnode)
* the new function dm_tree_node_add_cache_target which detects unknown
* feature flags and returns error for them.
*/
+DM_EXPORT_SYMBOL_BASE(dm_tree_node_add_cache_target)
int dm_tree_node_add_cache_target_base(struct dm_tree_node *node,
uint64_t size,
uint64_t feature_flags, /* DM_CACHE_FEATURE_* */
@@ -3883,7 +3885,6 @@ int dm_tree_node_add_cache_target_base(struct dm_tree_node *node,
const char *policy_name,
const struct dm_config_node *policy_settings,
uint32_t data_block_size);
-DM_EXPORT_SYMBOL_BASE(dm_tree_node_add_cache_target);
int dm_tree_node_add_cache_target_base(struct dm_tree_node *node,
uint64_t size,
uint64_t feature_flags,
diff --git a/libdm/libdm-stats.c b/libdm/libdm-stats.c
index 49d06802e..120ad4d68 100644
--- a/libdm/libdm-stats.c
+++ b/libdm/libdm-stats.c
@@ -2011,10 +2011,11 @@ out:
return r;
}
-int dm_stats_create_region(struct dm_stats *dms, uint64_t *region_id,
- uint64_t start, uint64_t len, int64_t step,
- int precise, struct dm_histogram *bounds,
- const char *program_id, const char *user_data)
+DM_EXPORT_NEW_SYMBOL(int, dm_stats_create_region, 1_02_107)
+ (struct dm_stats *dms, uint64_t *region_id,
+ uint64_t start, uint64_t len, int64_t step,
+ int precise, struct dm_histogram *bounds,
+ const char *program_id, const char *user_data)
{
char *hist_arg = NULL;
int r = 0;
@@ -2037,6 +2038,7 @@ out:
return r;
}
+
static void _stats_clear_group_regions(struct dm_stats *dms, uint64_t group_id)
{
struct dm_stats_group *group;
@@ -5070,6 +5072,8 @@ int dm_stats_start_filemapd(int fd, uint64_t group_id, const char *path,
*/
#if defined(GNU_SYMVER)
+
+DM_EXPORT_SYMBOL(dm_stats_create_region, 1_02_106)
int dm_stats_create_region_v1_02_106(struct dm_stats *dms, uint64_t *region_id,
uint64_t start, uint64_t len, int64_t step,
int precise, const char *program_id,
@@ -5083,8 +5087,8 @@ int dm_stats_create_region_v1_02_106(struct dm_stats *dms, uint64_t *region_id,
return _stats_create_region(dms, region_id, start, len, step, precise,
NULL, program_id, aux_data);
}
-DM_EXPORT_SYMBOL(dm_stats_create_region, 1_02_106);
+DM_EXPORT_SYMBOL(dm_stats_create_region, 1_02_104)
int dm_stats_create_region_v1_02_104(struct dm_stats *dms, uint64_t *region_id,
uint64_t start, uint64_t len, int64_t step,
const char *program_id, const char *aux_data);
@@ -5096,5 +5100,4 @@ int dm_stats_create_region_v1_02_104(struct dm_stats *dms, uint64_t *region_id,
return _stats_create_region(dms, region_id, start, len, step, 0, NULL,
program_id, aux_data);
}
-DM_EXPORT_SYMBOL(dm_stats_create_region, 1_02_104);
#endif
diff --git a/libdm/misc/dmlib.h b/libdm/misc/dmlib.h
index 85a22c50f..95f4b8ecb 100644
--- a/libdm/misc/dmlib.h
+++ b/libdm/misc/dmlib.h
@@ -22,6 +22,7 @@
/*
* Symbol export control macros
*
+ * DM_EXPORT_NEW_SYMBOL(rettype, func, ver)
* DM_EXPORT_SYMBOL(func,ver)
* DM_EXPORT_SYMBOL_BASE(func,ver)
*
@@ -40,19 +41,19 @@
* compatibility version should be enclosed in '#if defined(GNU_SYMVER)',
* for example:
*
- * int dm_foo(int bar)
+ * DM_EXPORT_NEW_SYMBOL(int, dm_foo, 1_02_107)(int bar)
* {
* return bar;
* }
*
- * #if defined(__GNUC__)
+ * #if defined(GNU_SYMVER)
* // Backward compatible dm_foo() version 1.02.104
+ * DM_EXPORT_SYMBOL(dm_foo,1_02_104)
* int dm_foo_v1_02_104(void);
* int dm_foo_v1_02_104(void)
* {
* return 0;
* }
- * DM_EXPORT_SYMBOL(dm_foo,1_02_104)
* #endif
*
* A prototype for the compatibility version is required as these
@@ -63,11 +64,27 @@
* versioning: it must never be used for new symbols.
*/
#if defined(GNU_SYMVER)
+# ifdef __has_attribute
+# if __has_attribute(symver)
+# define DM_EXPORT_NEW_SYMBOL(rettype, func, ver) \
+ __attribute__((__symver__( #func "@@DM_" #ver ))) \
+ __typeof__(func) func ##_v ##ver; \
+ rettype func ##_v ##ver
+# define DM_EXPORT_SYMBOL(func, ver) \
+ __attribute__((__symver__( #func "@DM_" #ver )))
+# define DM_EXPORT_SYMBOL_BASE(func) \
+ __attribute__((__symver__( #func "@Base" )))
+# endif
+# endif
+#ifndef DM_EXPORT_NEW_SYMBOL
+#define DM_EXPORT_NEW_SYMBOL(rettype, func, ver) rettype func
#define DM_EXPORT_SYMBOL(func, ver) \
- __asm__(".symver " #func "_v" #ver ", " #func "@DM_" #ver )
+ __asm__(".symver " #func "_v" #ver ", " #func "@DM_" #ver );
#define DM_EXPORT_SYMBOL_BASE(func) \
- __asm__(".symver " #func "_base, " #func "@Base" )
+ __asm__(".symver " #func "_base, " #func "@Base" );
+#endif
#else
+#define DM_EXPORT_NEW_SYMBOL(rettype, func, ver) rettype func
#define DM_EXPORT_SYMBOL(func, ver)
#define DM_EXPORT_SYMBOL_BASE(func)
#endif
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