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-rw-r--r--arch/powerpc/kernel/module_32.c77
-rw-r--r--arch/powerpc/kernel/module_64.c81
2 files changed, 127 insertions, 31 deletions
diff --git a/arch/powerpc/kernel/module_32.c b/arch/powerpc/kernel/module_32.c
index 07a89a39863..eab31385831 100644
--- a/arch/powerpc/kernel/module_32.c
+++ b/arch/powerpc/kernel/module_32.c
@@ -24,6 +24,7 @@
#include <linux/kernel.h>
#include <linux/cache.h>
#include <linux/bug.h>
+#include <linux/sort.h>
#include "setup.h"
@@ -54,22 +55,60 @@ void module_free(struct module *mod, void *module_region)
addend) */
static unsigned int count_relocs(const Elf32_Rela *rela, unsigned int num)
{
- unsigned int i, j, ret = 0;
-
- /* Sure, this is order(n^2), but it's usually short, and not
- time critical */
- for (i = 0; i < num; i++) {
- for (j = 0; j < i; j++) {
- /* If this addend appeared before, it's
- already been counted */
- if (ELF32_R_SYM(rela[i].r_info)
- == ELF32_R_SYM(rela[j].r_info)
- && rela[i].r_addend == rela[j].r_addend)
- break;
+ unsigned int i, r_info, r_addend, _count_relocs;
+
+ _count_relocs = 0;
+ r_info = 0;
+ r_addend = 0;
+ for (i = 0; i < num; i++)
+ /* Only count 24-bit relocs, others don't need stubs */
+ if (ELF32_R_TYPE(rela[i].r_info) == R_PPC_REL24 &&
+ (r_info != ELF32_R_SYM(rela[i].r_info) ||
+ r_addend != rela[i].r_addend)) {
+ _count_relocs++;
+ r_info = ELF32_R_SYM(rela[i].r_info);
+ r_addend = rela[i].r_addend;
}
- if (j == i) ret++;
+
+ return _count_relocs;
+}
+
+static int relacmp(const void *_x, const void *_y)
+{
+ const Elf32_Rela *x, *y;
+
+ y = (Elf32_Rela *)_x;
+ x = (Elf32_Rela *)_y;
+
+ /* Compare the entire r_info (as opposed to ELF32_R_SYM(r_info) only) to
+ * make the comparison cheaper/faster. It won't affect the sorting or
+ * the counting algorithms' performance
+ */
+ if (x->r_info < y->r_info)
+ return -1;
+ else if (x->r_info > y->r_info)
+ return 1;
+ else if (x->r_addend < y->r_addend)
+ return -1;
+ else if (x->r_addend > y->r_addend)
+ return 1;
+ else
+ return 0;
+}
+
+static void relaswap(void *_x, void *_y, int size)
+{
+ uint32_t *x, *y, tmp;
+ int i;
+
+ y = (uint32_t *)_x;
+ x = (uint32_t *)_y;
+
+ for (i = 0; i < sizeof(Elf32_Rela) / sizeof(uint32_t); i++) {
+ tmp = x[i];
+ x[i] = y[i];
+ y[i] = tmp;
}
- return ret;
}
/* Get the potential trampolines size required of the init and
@@ -100,6 +139,16 @@ static unsigned long get_plt_size(const Elf32_Ehdr *hdr,
DEBUGP("Ptr: %p. Number: %u\n",
(void *)hdr + sechdrs[i].sh_offset,
sechdrs[i].sh_size / sizeof(Elf32_Rela));
+
+ /* Sort the relocation information based on a symbol and
+ * addend key. This is a stable O(n*log n) complexity
+ * alogrithm but it will reduce the complexity of
+ * count_relocs() to linear complexity O(n)
+ */
+ sort((void *)hdr + sechdrs[i].sh_offset,
+ sechdrs[i].sh_size / sizeof(Elf32_Rela),
+ sizeof(Elf32_Rela), relacmp, relaswap);
+
ret += count_relocs((void *)hdr
+ sechdrs[i].sh_offset,
sechdrs[i].sh_size
diff --git a/arch/powerpc/kernel/module_64.c b/arch/powerpc/kernel/module_64.c
index 75c7c4f1928..3a82b02b784 100644
--- a/arch/powerpc/kernel/module_64.c
+++ b/arch/powerpc/kernel/module_64.c
@@ -24,6 +24,7 @@
#include <asm/module.h>
#include <asm/uaccess.h>
#include <asm/firmware.h>
+#include <linux/sort.h>
#include "setup.h"
@@ -81,25 +82,23 @@ static struct ppc64_stub_entry ppc64_stub =
different addend) */
static unsigned int count_relocs(const Elf64_Rela *rela, unsigned int num)
{
- unsigned int i, j, ret = 0;
+ unsigned int i, r_info, r_addend, _count_relocs;
/* FIXME: Only count external ones --RR */
- /* Sure, this is order(n^2), but it's usually short, and not
- time critical */
- for (i = 0; i < num; i++) {
+ _count_relocs = 0;
+ r_info = 0;
+ r_addend = 0;
+ for (i = 0; i < num; i++)
/* Only count 24-bit relocs, others don't need stubs */
- if (ELF64_R_TYPE(rela[i].r_info) != R_PPC_REL24)
- continue;
- for (j = 0; j < i; j++) {
- /* If this addend appeared before, it's
- already been counted */
- if (rela[i].r_info == rela[j].r_info
- && rela[i].r_addend == rela[j].r_addend)
- break;
+ if (ELF64_R_TYPE(rela[i].r_info) == R_PPC_REL24 &&
+ (r_info != ELF64_R_SYM(rela[i].r_info) ||
+ r_addend != rela[i].r_addend)) {
+ _count_relocs++;
+ r_info = ELF64_R_SYM(rela[i].r_info);
+ r_addend = rela[i].r_addend;
}
- if (j == i) ret++;
- }
- return ret;
+
+ return _count_relocs;
}
void *module_alloc(unsigned long size)
@@ -118,6 +117,44 @@ void module_free(struct module *mod, void *module_region)
table entries. */
}
+static int relacmp(const void *_x, const void *_y)
+{
+ const Elf64_Rela *x, *y;
+
+ y = (Elf64_Rela *)_x;
+ x = (Elf64_Rela *)_y;
+
+ /* Compare the entire r_info (as opposed to ELF64_R_SYM(r_info) only) to
+ * make the comparison cheaper/faster. It won't affect the sorting or
+ * the counting algorithms' performance
+ */
+ if (x->r_info < y->r_info)
+ return -1;
+ else if (x->r_info > y->r_info)
+ return 1;
+ else if (x->r_addend < y->r_addend)
+ return -1;
+ else if (x->r_addend > y->r_addend)
+ return 1;
+ else
+ return 0;
+}
+
+static void relaswap(void *_x, void *_y, int size)
+{
+ uint64_t *x, *y, tmp;
+ int i;
+
+ y = (uint64_t *)_x;
+ x = (uint64_t *)_y;
+
+ for (i = 0; i < sizeof(Elf64_Rela) / sizeof(uint64_t); i++) {
+ tmp = x[i];
+ x[i] = y[i];
+ y[i] = tmp;
+ }
+}
+
/* Get size of potential trampolines required. */
static unsigned long get_stubs_size(const Elf64_Ehdr *hdr,
const Elf64_Shdr *sechdrs)
@@ -133,6 +170,16 @@ static unsigned long get_stubs_size(const Elf64_Ehdr *hdr,
DEBUGP("Ptr: %p. Number: %lu\n",
(void *)sechdrs[i].sh_addr,
sechdrs[i].sh_size / sizeof(Elf64_Rela));
+
+ /* Sort the relocation information based on a symbol and
+ * addend key. This is a stable O(n*log n) complexity
+ * alogrithm but it will reduce the complexity of
+ * count_relocs() to linear complexity O(n)
+ */
+ sort((void *)sechdrs[i].sh_addr,
+ sechdrs[i].sh_size / sizeof(Elf64_Rela),
+ sizeof(Elf64_Rela), relacmp, relaswap);
+
relocs += count_relocs((void *)sechdrs[i].sh_addr,
sechdrs[i].sh_size
/ sizeof(Elf64_Rela));
@@ -343,7 +390,7 @@ int apply_relocate_add(Elf64_Shdr *sechdrs,
/* Simply set it */
*(u32 *)location = value;
break;
-
+
case R_PPC64_ADDR64:
/* Simply set it */
*(unsigned long *)location = value;
@@ -399,7 +446,7 @@ int apply_relocate_add(Elf64_Shdr *sechdrs,
}
/* Only replace bits 2 through 26 */
- *(uint32_t *)location
+ *(uint32_t *)location
= (*(uint32_t *)location & ~0x03fffffc)
| (value & 0x03fffffc);
break;
generated by cgit v1.2.3 (git 2.25.1) at 2024-12-19 02:14:48 +0000