[lvm-devel] master - libdm: Introduce dm_malloc_aligned
Alasdair Kergon
agk at sourceware.org
Wed Jan 10 15:53:22 UTC 2018
Gitweb: https://sourceware.org/git/?p=lvm2.git;a=commitdiff;h=ea96381534360d6a893f0a48db8dd15fcb9ced33
Commit: ea96381534360d6a893f0a48db8dd15fcb9ced33
Parent: 943b21779770f1cd93e73925e62f108e2efbd6cc
Author: Alasdair G Kergon <agk at redhat.com>
AuthorDate: Tue Jan 9 20:25:43 2018 +0000
Committer: Alasdair G Kergon <agk at redhat.com>
CommitterDate: Wed Jan 10 15:48:03 2018 +0000
libdm: Introduce dm_malloc_aligned
---
WHATS_NEW_DM | 1 +
lib/device/dev-io.c | 10 ++++++++-
lib/label/label.c | 1 -
libdm/.exported_symbols.DM_1_02_147 | 1 +
libdm/libdevmapper.h | 3 ++
libdm/mm/dbg_malloc.c | 38 ++++++++++++++++++++++++++++++++++-
6 files changed, 51 insertions(+), 3 deletions(-)
diff --git a/WHATS_NEW_DM b/WHATS_NEW_DM
index bcd6deb..5c6b888 100644
--- a/WHATS_NEW_DM
+++ b/WHATS_NEW_DM
@@ -1,5 +1,6 @@
Version 1.02.147 -
=====================================
+ Introduce dm_malloc_aligned for page alignment of buffers.
Version 1.02.146 - 18th December 2017
=====================================
diff --git a/lib/device/dev-io.c b/lib/device/dev-io.c
index 22a0d4c..ee4a0a5 100644
--- a/lib/device/dev-io.c
+++ b/lib/device/dev-io.c
@@ -257,6 +257,13 @@ static int _aligned_io(struct device_area *where, char *buffer,
/* Perform the I/O directly. */
return _io(where, buffer, should_write, reason);
+#ifndef DEBUG_MEM
+ /* Allocate a bounce buffer with an extra block */
+ if (!(bounce_buf = bounce = dm_malloc_aligned((size_t) widened.size, 0))) {
+ log_error("Bounce buffer malloc failed");
+ return 0;
+ }
+#else
/* Allocate a bounce buffer with an extra block */
if (!(bounce_buf = bounce = dm_malloc((size_t) widened.size + block_size))) {
log_error("Bounce buffer malloc failed");
@@ -268,6 +275,7 @@ static int _aligned_io(struct device_area *where, char *buffer,
*/
if (((uintptr_t) bounce) & mask)
bounce = (char *) ((((uintptr_t) bounce) + mask) & ~mask);
+#endif
/* Do we need to read into the bounce buffer? */
if ((!should_write || buffer_was_widened) &&
@@ -887,7 +895,7 @@ int dev_write(struct device *dev, uint64_t offset, size_t len, dev_io_reason_t r
int dev_set(struct device *dev, uint64_t offset, size_t len, dev_io_reason_t reason, int value)
{
size_t s;
- char buffer[4096] __attribute__((aligned(8)));
+ char buffer[4096] __attribute__((aligned(4096)));
if (!dev_open(dev))
return_0;
diff --git a/lib/label/label.c b/lib/label/label.c
index 3a5c9fc..ccee95d 100644
--- a/lib/label/label.c
+++ b/lib/label/label.c
@@ -318,7 +318,6 @@ static int _label_read(struct device *dev, uint64_t scan_sector, struct label **
{
struct lvmcache_info *info;
struct find_labeller_params *flp;
- char *readbuf = NULL;
if ((info = lvmcache_info_from_pvid(dev->pvid, dev, 1))) {
log_debug_devs("Reading label from lvmcache for %s", dev_name(dev));
diff --git a/libdm/.exported_symbols.DM_1_02_147 b/libdm/.exported_symbols.DM_1_02_147
new file mode 100644
index 0000000..97f00f7
--- /dev/null
+++ b/libdm/.exported_symbols.DM_1_02_147
@@ -0,0 +1 @@
+dm_malloc_aligned_wrapper
diff --git a/libdm/libdevmapper.h b/libdm/libdevmapper.h
index 5e77906..2438f74 100644
--- a/libdm/libdevmapper.h
+++ b/libdm/libdevmapper.h
@@ -2075,6 +2075,8 @@ uint32_t dm_tree_get_cookie(struct dm_tree_node *node);
*/
void *dm_malloc_wrapper(size_t s, const char *file, int line)
__attribute__((__malloc__)) __attribute__((__warn_unused_result__));
+void *dm_malloc_aligned_wrapper(size_t s, size_t a, const char *file, int line)
+ __attribute__((__malloc__)) __attribute__((__warn_unused_result__));
void *dm_zalloc_wrapper(size_t s, const char *file, int line)
__attribute__((__malloc__)) __attribute__((__warn_unused_result__));
void *dm_realloc_wrapper(void *p, unsigned int s, const char *file, int line)
@@ -2086,6 +2088,7 @@ int dm_dump_memory_wrapper(void);
void dm_bounds_check_wrapper(void);
#define dm_malloc(s) dm_malloc_wrapper((s), __FILE__, __LINE__)
+#define dm_malloc_aligned(s, a) dm_malloc_aligned_wrapper((s), (a), __FILE__, __LINE__)
#define dm_zalloc(s) dm_zalloc_wrapper((s), __FILE__, __LINE__)
#define dm_strdup(s) dm_strdup_wrapper((s), __FILE__, __LINE__)
#define dm_free(p) dm_free_wrapper(p)
diff --git a/libdm/mm/dbg_malloc.c b/libdm/mm/dbg_malloc.c
index 0667bf3..f108e7b 100644
--- a/libdm/mm/dbg_malloc.c
+++ b/libdm/mm/dbg_malloc.c
@@ -18,7 +18,6 @@
#ifdef VALGRIND_POOL
#include "memcheck.h"
#endif
-
#include <assert.h>
#include <stdarg.h>
@@ -26,6 +25,8 @@ void *dm_malloc_aux(size_t s, const char *file, int line)
__attribute__((__malloc__)) __attribute__((__warn_unused_result__));
void *dm_malloc_aux_debug(size_t s, const char *file, int line)
__attribute__((__malloc__)) __attribute__((__warn_unused_result__));
+static void *_dm_malloc_aligned_aux(size_t s, size_t a, const char *file, int line)
+ __attribute__((__malloc__)) __attribute__((__warn_unused_result__));
void *dm_zalloc_aux(size_t s, const char *file, int line)
__attribute__((__malloc__)) __attribute__((__warn_unused_result__));
void *dm_zalloc_aux_debug(size_t s, const char *file, int line)
@@ -286,6 +287,30 @@ void *dm_malloc_aux(size_t s, const char *file __attribute__((unused)),
return malloc(s);
}
+/* Allocate size s with alignment a (or page size if 0) */
+static void *_dm_malloc_aligned_aux(size_t s, size_t a, const char *file __attribute__((unused)),
+ int line __attribute__((unused)))
+{
+ void *memptr;
+ int r;
+
+ if (!a)
+ a = getpagesize();
+
+ if (s > 50000000) {
+ log_error("Huge memory allocation (size %" PRIsize_t
+ ") rejected - metadata corruption?", s);
+ return 0;
+ }
+
+ if ((r = posix_memalign(&memptr, a, s))) {
+ log_error("Failed to allocate %" PRIsize_t " bytes aligned to %d: %s", s, a, strerror(r));
+ return 0;
+ }
+
+ return memptr;
+}
+
void *dm_zalloc_aux(size_t s, const char *file, int line)
{
void *ptr = dm_malloc_aux(s, file, line);
@@ -303,6 +328,12 @@ void *dm_malloc_wrapper(size_t s, const char *file, int line)
return dm_malloc_aux_debug(s, file, line);
}
+void *dm_malloc_aligned_wrapper(size_t s, size_t a, const char *file, int line)
+{
+ /* FIXME Implement alignment when debugging - currently just ignored */
+ return _dm_malloc_aux_debug(s, file, line);
+}
+
void *dm_zalloc_wrapper(size_t s, const char *file, int line)
{
return dm_zalloc_aux_debug(s, file, line);
@@ -340,6 +371,11 @@ void *dm_malloc_wrapper(size_t s, const char *file, int line)
return dm_malloc_aux(s, file, line);
}
+void *dm_malloc_aligned_wrapper(size_t s, size_t a, const char *file, int line)
+{
+ return _dm_malloc_aligned_aux(s, a, file, line);
+}
+
void *dm_zalloc_wrapper(size_t s, const char *file, int line)
{
return dm_zalloc_aux(s, file, line);
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