diff options
Diffstat (limited to 'arch/ia64/kernel/ftrace.c')
| -rw-r--r-- | arch/ia64/kernel/ftrace.c | 196 |
1 files changed, 0 insertions, 196 deletions
diff --git a/arch/ia64/kernel/ftrace.c b/arch/ia64/kernel/ftrace.c deleted file mode 100644 index d6360fd404..0000000000 --- a/arch/ia64/kernel/ftrace.c +++ /dev/null @@ -1,196 +0,0 @@ -/* - * Dynamic function tracing support. - * - * Copyright (C) 2008 Shaohua Li <shaohua.li@intel.com> - * - * For licencing details, see COPYING. - * - * Defines low-level handling of mcount calls when the kernel - * is compiled with the -pg flag. When using dynamic ftrace, the - * mcount call-sites get patched lazily with NOP till they are - * enabled. All code mutation routines here take effect atomically. - */ - -#include <linux/uaccess.h> -#include <linux/ftrace.h> - -#include <asm/cacheflush.h> -#include <asm/patch.h> - -/* In IA64, each function will be added below two bundles with -pg option */ -static unsigned char __attribute__((aligned(8))) -ftrace_orig_code[MCOUNT_INSN_SIZE] = { - 0x02, 0x40, 0x31, 0x10, 0x80, 0x05, /* alloc r40=ar.pfs,12,8,0 */ - 0xb0, 0x02, 0x00, 0x00, 0x42, 0x40, /* mov r43=r0;; */ - 0x05, 0x00, 0xc4, 0x00, /* mov r42=b0 */ - 0x11, 0x48, 0x01, 0x02, 0x00, 0x21, /* mov r41=r1 */ - 0x00, 0x00, 0x00, 0x02, 0x00, 0x00, /* nop.i 0x0 */ - 0x08, 0x00, 0x00, 0x50 /* br.call.sptk.many b0 = _mcount;; */ -}; - -struct ftrace_orig_insn { - u64 dummy1, dummy2, dummy3; - u64 dummy4:64-41+13; - u64 imm20:20; - u64 dummy5:3; - u64 sign:1; - u64 dummy6:4; -}; - -/* mcount stub will be converted below for nop */ -static unsigned char ftrace_nop_code[MCOUNT_INSN_SIZE] = { - 0x00, 0x00, 0x00, 0x00, 0x01, 0x00, /* [MII] nop.m 0x0 */ - 0x30, 0x00, 0x00, 0x60, 0x00, 0x00, /* mov r3=ip */ - 0x00, 0x00, 0x04, 0x00, /* nop.i 0x0 */ - 0x05, 0x00, 0x00, 0x00, 0x01, 0x00, /* [MLX] nop.m 0x0 */ - 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* nop.x 0x0;; */ - 0x00, 0x00, 0x04, 0x00 -}; - -static unsigned char *ftrace_nop_replace(void) -{ - return ftrace_nop_code; -} - -/* - * mcount stub will be converted below for call - * Note: Just the last instruction is changed against nop - * */ -static unsigned char __attribute__((aligned(8))) -ftrace_call_code[MCOUNT_INSN_SIZE] = { - 0x00, 0x00, 0x00, 0x00, 0x01, 0x00, /* [MII] nop.m 0x0 */ - 0x30, 0x00, 0x00, 0x60, 0x00, 0x00, /* mov r3=ip */ - 0x00, 0x00, 0x04, 0x00, /* nop.i 0x0 */ - 0x05, 0x00, 0x00, 0x00, 0x01, 0x00, /* [MLX] nop.m 0x0 */ - 0xff, 0xff, 0xff, 0xff, 0x7f, 0x00, /* brl.many .;;*/ - 0xf8, 0xff, 0xff, 0xc8 -}; - -struct ftrace_call_insn { - u64 dummy1, dummy2; - u64 dummy3:48; - u64 imm39_l:16; - u64 imm39_h:23; - u64 dummy4:13; - u64 imm20:20; - u64 dummy5:3; - u64 i:1; - u64 dummy6:4; -}; - -static unsigned char *ftrace_call_replace(unsigned long ip, unsigned long addr) -{ - struct ftrace_call_insn *code = (void *)ftrace_call_code; - unsigned long offset = addr - (ip + 0x10); - - code->imm39_l = offset >> 24; - code->imm39_h = offset >> 40; - code->imm20 = offset >> 4; - code->i = offset >> 63; - return ftrace_call_code; -} - -static int -ftrace_modify_code(unsigned long ip, unsigned char *old_code, - unsigned char *new_code, int do_check) -{ - unsigned char replaced[MCOUNT_INSN_SIZE]; - - /* - * Note: - * We are paranoid about modifying text, as if a bug was to happen, it - * could cause us to read or write to someplace that could cause harm. - * Carefully read and modify the code with probe_kernel_*(), and make - * sure what we read is what we expected it to be before modifying it. - */ - - if (!do_check) - goto skip_check; - - /* read the text we want to modify */ - if (copy_from_kernel_nofault(replaced, (void *)ip, MCOUNT_INSN_SIZE)) - return -EFAULT; - - /* Make sure it is what we expect it to be */ - if (memcmp(replaced, old_code, MCOUNT_INSN_SIZE) != 0) - return -EINVAL; - -skip_check: - /* replace the text with the new text */ - if (copy_to_kernel_nofault(((void *)ip), new_code, MCOUNT_INSN_SIZE)) - return -EPERM; - flush_icache_range(ip, ip + MCOUNT_INSN_SIZE); - - return 0; -} - -static int ftrace_make_nop_check(struct dyn_ftrace *rec, unsigned long addr) -{ - unsigned char __attribute__((aligned(8))) replaced[MCOUNT_INSN_SIZE]; - unsigned long ip = rec->ip; - - if (copy_from_kernel_nofault(replaced, (void *)ip, MCOUNT_INSN_SIZE)) - return -EFAULT; - if (rec->flags & FTRACE_FL_CONVERTED) { - struct ftrace_call_insn *call_insn, *tmp_call; - - call_insn = (void *)ftrace_call_code; - tmp_call = (void *)replaced; - call_insn->imm39_l = tmp_call->imm39_l; - call_insn->imm39_h = tmp_call->imm39_h; - call_insn->imm20 = tmp_call->imm20; - call_insn->i = tmp_call->i; - if (memcmp(replaced, ftrace_call_code, MCOUNT_INSN_SIZE) != 0) - return -EINVAL; - return 0; - } else { - struct ftrace_orig_insn *call_insn, *tmp_call; - - call_insn = (void *)ftrace_orig_code; - tmp_call = (void *)replaced; - call_insn->sign = tmp_call->sign; - call_insn->imm20 = tmp_call->imm20; - if (memcmp(replaced, ftrace_orig_code, MCOUNT_INSN_SIZE) != 0) - return -EINVAL; - return 0; - } -} - -int ftrace_make_nop(struct module *mod, - struct dyn_ftrace *rec, unsigned long addr) -{ - int ret; - char *new; - - ret = ftrace_make_nop_check(rec, addr); - if (ret) - return ret; - new = ftrace_nop_replace(); - return ftrace_modify_code(rec->ip, NULL, new, 0); -} - -int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr) -{ - unsigned long ip = rec->ip; - unsigned char *old, *new; - - old= ftrace_nop_replace(); - new = ftrace_call_replace(ip, addr); - return ftrace_modify_code(ip, old, new, 1); -} - -/* in IA64, _mcount can't directly call ftrace_stub. Only jump is ok */ -int ftrace_update_ftrace_func(ftrace_func_t func) -{ - unsigned long ip; - unsigned long addr = ((struct fnptr *)ftrace_call)->ip; - - if (func == ftrace_stub) - return 0; - ip = ((struct fnptr *)func)->ip; - - ia64_patch_imm64(addr + 2, ip); - - flush_icache_range(addr, addr + 16); - return 0; -} |