diff options
Diffstat (limited to 'arch/powerpc/kernel/module_64.c')
| -rw-r--r-- | arch/powerpc/kernel/module_64.c | 66 |
1 files changed, 57 insertions, 9 deletions
diff --git a/arch/powerpc/kernel/module_64.c b/arch/powerpc/kernel/module_64.c index 135960918d14..45dac7b46aa3 100644 --- a/arch/powerpc/kernel/module_64.c +++ b/arch/powerpc/kernel/module_64.c @@ -205,7 +205,9 @@ static int relacmp(const void *_x, const void *_y) /* Get size of potential trampolines required. */ static unsigned long get_stubs_size(const Elf64_Ehdr *hdr, - const Elf64_Shdr *sechdrs) + const Elf64_Shdr *sechdrs, + char *secstrings, + struct module *me) { /* One extra reloc so it's always 0-addr terminated */ unsigned long relocs = 1; @@ -241,13 +243,25 @@ static unsigned long get_stubs_size(const Elf64_Ehdr *hdr, } } -#ifdef CONFIG_DYNAMIC_FTRACE - /* make the trampoline to the ftrace_caller */ - relocs++; -#ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS - /* an additional one for ftrace_regs_caller */ - relocs++; -#endif + /* stubs for ftrace_caller and ftrace_regs_caller */ + relocs += IS_ENABLED(CONFIG_DYNAMIC_FTRACE) + IS_ENABLED(CONFIG_DYNAMIC_FTRACE_WITH_REGS); + +#ifdef CONFIG_PPC_FTRACE_OUT_OF_LINE + /* stubs for the function tracer */ + for (i = 1; i < hdr->e_shnum; i++) { + if (!strcmp(secstrings + sechdrs[i].sh_name, "__patchable_function_entries")) { + me->arch.ool_stub_count = sechdrs[i].sh_size / sizeof(unsigned long); + me->arch.ool_stub_index = 0; + relocs += roundup(me->arch.ool_stub_count * sizeof(struct ftrace_ool_stub), + sizeof(struct ppc64_stub_entry)) / + sizeof(struct ppc64_stub_entry); + break; + } + } + if (i == hdr->e_shnum) { + pr_err("%s: doesn't contain __patchable_function_entries.\n", me->name); + return -ENOEXEC; + } #endif pr_debug("Looks like a total of %lu stubs, max\n", relocs); @@ -460,7 +474,7 @@ int module_frob_arch_sections(Elf64_Ehdr *hdr, #endif /* Override the stubs size */ - sechdrs[me->arch.stubs_section].sh_size = get_stubs_size(hdr, sechdrs); + sechdrs[me->arch.stubs_section].sh_size = get_stubs_size(hdr, sechdrs, secstrings, me); return 0; } @@ -1085,6 +1099,37 @@ int module_trampoline_target(struct module *mod, unsigned long addr, return 0; } +static int setup_ftrace_ool_stubs(const Elf64_Shdr *sechdrs, unsigned long addr, struct module *me) +{ +#ifdef CONFIG_PPC_FTRACE_OUT_OF_LINE + unsigned int i, total_stubs, num_stubs; + struct ppc64_stub_entry *stub; + + total_stubs = sechdrs[me->arch.stubs_section].sh_size / sizeof(*stub); + num_stubs = roundup(me->arch.ool_stub_count * sizeof(struct ftrace_ool_stub), + sizeof(struct ppc64_stub_entry)) / sizeof(struct ppc64_stub_entry); + + /* Find the next available entry */ + stub = (void *)sechdrs[me->arch.stubs_section].sh_addr; + for (i = 0; stub_func_addr(stub[i].funcdata); i++) + if (WARN_ON(i >= total_stubs)) + return -1; + + if (WARN_ON(i + num_stubs > total_stubs)) + return -1; + + stub += i; + me->arch.ool_stubs = (struct ftrace_ool_stub *)stub; + + /* reserve stubs */ + for (i = 0; i < num_stubs; i++) + if (patch_u32((void *)&stub->funcdata, PPC_RAW_NOP())) + return -1; +#endif + + return 0; +} + int module_finalize_ftrace(struct module *mod, const Elf_Shdr *sechdrs) { mod->arch.tramp = stub_for_addr(sechdrs, @@ -1103,6 +1148,9 @@ int module_finalize_ftrace(struct module *mod, const Elf_Shdr *sechdrs) if (!mod->arch.tramp) return -ENOENT; + if (setup_ftrace_ool_stubs(sechdrs, mod->arch.tramp, mod)) + return -ENOENT; + return 0; } #endif |