author: Shile Zhang <shile.zhang@linux.alibaba.com> 2019-12-04 08:46:31 +0800
committer: Ingo Molnar <mingo@kernel.org> 2019-12-13 10:47:58 +0100
commit: 1091670637be8bd34a39dd1ddcc0a10a7c88d4e2
parent: 57cafdf2a04e161b9654c4ae3888a7549594c499
Commit Summary:
Diffstat:
1 file changed, 190 insertions, 0 deletions
diff --git a/scripts/sorttable.h b/scripts/sorttable.h
new file mode 100644
index 000000000000..82589ff90e25
--- /dev/null
+++ b/scripts/sorttable.h
@@ -0,0 +1,210 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * sorttable.h
+ *
+ * Copyright 2011 - 2012 Cavium, Inc.
+ *
+ * Some of this code was taken out of recordmcount.h written by:
+ *
+ * Copyright 2009 John F. Reiser <jreiser@BitWagon.com>. All rights reserved.
+ * Copyright 2010 Steven Rostedt <srostedt@redhat.com>, Red Hat Inc.
+ */
+
+#undef extable_ent_size
+#undef compare_extable
+#undef do_sort
+#undef Elf_Addr
+#undef Elf_Ehdr
+#undef Elf_Shdr
+#undef Elf_Rel
+#undef Elf_Rela
+#undef Elf_Sym
+#undef ELF_R_SYM
+#undef Elf_r_sym
+#undef ELF_R_INFO
+#undef Elf_r_info
+#undef ELF_ST_BIND
+#undef ELF_ST_TYPE
+#undef fn_ELF_R_SYM
+#undef fn_ELF_R_INFO
+#undef uint_t
+#undef _r
+#undef _w
+
+#ifdef SORTTABLE_64
+# define extable_ent_size 16
+# define compare_extable compare_extable_64
+# define do_sort do_sort_64
+# define Elf_Addr Elf64_Addr
+# define Elf_Ehdr Elf64_Ehdr
+# define Elf_Shdr Elf64_Shdr
+# define Elf_Rel Elf64_Rel
+# define Elf_Rela Elf64_Rela
+# define Elf_Sym Elf64_Sym
+# define ELF_R_SYM ELF64_R_SYM
+# define Elf_r_sym Elf64_r_sym
+# define ELF_R_INFO ELF64_R_INFO
+# define Elf_r_info Elf64_r_info
+# define ELF_ST_BIND ELF64_ST_BIND
+# define ELF_ST_TYPE ELF64_ST_TYPE
+# define fn_ELF_R_SYM fn_ELF64_R_SYM
+# define fn_ELF_R_INFO fn_ELF64_R_INFO
+# define uint_t uint64_t
+# define _r r8
+# define _w w8
+#else
+# define extable_ent_size 8
+# define compare_extable compare_extable_32
+# define do_sort do_sort_32
+# define Elf_Addr Elf32_Addr
+# define Elf_Ehdr Elf32_Ehdr
+# define Elf_Shdr Elf32_Shdr
+# define Elf_Rel Elf32_Rel
+# define Elf_Rela Elf32_Rela
+# define Elf_Sym Elf32_Sym
+# define ELF_R_SYM ELF32_R_SYM
+# define Elf_r_sym Elf32_r_sym
+# define ELF_R_INFO ELF32_R_INFO
+# define Elf_r_info Elf32_r_info
+# define ELF_ST_BIND ELF32_ST_BIND
+# define ELF_ST_TYPE ELF32_ST_TYPE
+# define fn_ELF_R_SYM fn_ELF32_R_SYM
+# define fn_ELF_R_INFO fn_ELF32_R_INFO
+# define uint_t uint32_t
+# define _r r
+# define _w w
+#endif
+
+static int compare_extable(const void *a, const void *b)
+{
+ Elf_Addr av = _r(a);
+ Elf_Addr bv = _r(b);
+
+ if (av < bv)
+ return -1;
+ if (av > bv)
+ return 1;
+ return 0;
+}
+
+static int do_sort(Elf_Ehdr *ehdr,
+ char const *const fname,
+ table_sort_t custom_sort)
+{
+ Elf_Shdr *s, *shdr = (Elf_Shdr *)((char *)ehdr + _r(&ehdr->e_shoff));
+ Elf_Shdr *strtab_sec = NULL;
+ Elf_Shdr *symtab_sec = NULL;
+ Elf_Shdr *extab_sec = NULL;
+ Elf_Sym *sym;
+ const Elf_Sym *symtab;
+ Elf32_Word *symtab_shndx = NULL;
+ Elf_Sym *sort_needed_sym = NULL;
+ Elf_Shdr *sort_needed_sec;
+ Elf_Rel *relocs = NULL;
+ int relocs_size = 0;
+ uint32_t *sort_needed_loc;
+ const char *secstrings;
+ const char *strtab;
+ char *extab_image;
+ int extab_index = 0;
+ int i;
+ int idx;
+ unsigned int shnum;
+ unsigned int shstrndx;
+
+ shstrndx = r2(&ehdr->e_shstrndx);
+ if (shstrndx == SHN_XINDEX)
+ shstrndx = r(&shdr[0].sh_link);
+ secstrings = (const char *)ehdr + _r(&shdr[shstrndx].sh_offset);
+
+ shnum = r2(&ehdr->e_shnum);
+ if (shnum == SHN_UNDEF)
+ shnum = _r(&shdr[0].sh_size);
+
+ for (i = 0, s = shdr; s < shdr + shnum; i++, s++) {
+ idx = r(&s->sh_name);
+ if (!strcmp(secstrings + idx, "__ex_table")) {
+ extab_sec = s;
+ extab_index = i;
+ }
+ if (!strcmp(secstrings + idx, ".symtab"))
+ symtab_sec = s;
+ if (!strcmp(secstrings + idx, ".strtab"))
+ strtab_sec = s;
+
+ if ((r(&s->sh_type) == SHT_REL ||
+ r(&s->sh_type) == SHT_RELA) &&
+ r(&s->sh_info) == extab_index) {
+ relocs = (void *)ehdr + _r(&s->sh_offset);
+ relocs_size = _r(&s->sh_size);
+ }
+ if (r(&s->sh_type) == SHT_SYMTAB_SHNDX)
+ symtab_shndx = (Elf32_Word *)((const char *)ehdr +
+ _r(&s->sh_offset));
+ }
+
+ if (!extab_sec) {
+ fprintf(stderr, "no __ex_table in file: %s\n", fname);
+ return -1;
+ }
+
+ if (!symtab_sec) {
+ fprintf(stderr, "no .symtab in file: %s\n", fname);
+ return -1;
+ }
+
+ if (!strtab_sec) {
+ fprintf(stderr, "no .strtab in file: %s\n", fname);
+ return -1;
+ }
+
+ extab_image = (void *)ehdr + _r(&extab_sec->sh_offset);
+ strtab = (const char *)ehdr + _r(&strtab_sec->sh_offset);
+ symtab = (const Elf_Sym *)((const char *)ehdr +
+ _r(&symtab_sec->sh_offset));
+
+ if (custom_sort) {
+ custom_sort(extab_image, _r(&extab_sec->sh_size));
+ } else {
+ int num_entries = _r(&extab_sec->sh_size) / extable_ent_size;
+ qsort(extab_image, num_entries,
+ extable_ent_size, compare_extable);
+ }
+
+ /* If there were relocations, we no longer need them. */
+ if (relocs)
+ memset(relocs, 0, relocs_size);
+
+ /* find the flag main_extable_sort_needed */
+ for (sym = (void *)ehdr + _r(&symtab_sec->sh_offset);
+ sym < sym + _r(&symtab_sec->sh_size) / sizeof(Elf_Sym);
+ sym++) {
+ if (ELF_ST_TYPE(sym->st_info) != STT_OBJECT)
+ continue;
+ if (!strcmp(strtab + r(&sym->st_name),
+ "main_extable_sort_needed")) {
+ sort_needed_sym = sym;
+ break;
+ }
+ }
+
+ if (!sort_needed_sym) {
+ fprintf(stderr,
+ "no main_extable_sort_needed symbol in file: %s\n",
+ fname);
+ return -1;
+ }
+
+ sort_needed_sec = &shdr[get_secindex(r2(&sym->st_shndx),
+ sort_needed_sym - symtab,
+ symtab_shndx)];
+ sort_needed_loc = (void *)ehdr +
+ _r(&sort_needed_sec->sh_offset) +
+ _r(&sort_needed_sym->st_value) -
+ _r(&sort_needed_sec->sh_addr);
+
+ /* extable has been sorted, clear the flag */
+ w(0, sort_needed_loc);
+
+ return 0;
+}