// SPDX-License-Identifier: GPL-2.0-only/* * recordmcount.c: construct a table of the locations of calls to 'mcount' * so that ftrace can find them quickly. * Copyright 2009 John F. Reiser <jreiser@BitWagon.com>. All rights reserved. * * Restructured to fit Linux format, as well as other updates: * Copyright 2010 Steven Rostedt <srostedt@redhat.com>, Red Hat Inc. */ /* * Strategy: alter the .o file in-place. * * Append a new STRTAB that has the new section names, followed by a new array * ElfXX_Shdr[] that has the new section headers, followed by the section * contents for __mcount_loc and its relocations. The old shstrtab strings, * and the old ElfXX_Shdr[] array, remain as "garbage" (commonly, a couple * kilobytes.) Subsequent processing by /bin/ld (or the kernel module loader) * will ignore the garbage regions, because they are not designated by the * new .e_shoff nor the new ElfXX_Shdr[]. [In order to remove the garbage, * then use "ld -r" to create a new file that omits the garbage.] */ #include <sys/types.h>#include <sys/mman.h>#include <sys/stat.h>#include <getopt.h>#include <elf.h>#include <fcntl.h>#include <stdio.h>#include <stdlib.h>#include <string.h>#include <unistd.h> #ifndef EM_AARCH64#define EM_AARCH64 183#define R_AARCH64_NONE 0#define R_AARCH64_ABS64 257#endif #define R_ARM_PC24 1#define R_ARM_THM_CALL 10#define R_ARM_CALL 28 static int fd_map; /* File descriptor for file being modified. */static int mmap_failed; /* Boolean flag. */static char gpfx; /* prefix for global symbol name (sometimes '_') */static struct stat sb; /* Remember .st_size, etc. */static const char *altmcount; /* alternate mcount symbol name */static int warn_on_notrace_sect; /* warn when section has mcount not being recorded */static void *file_map; /* pointer of the mapped file */static void *file_end; /* pointer to the end of the mapped file */static int file_updated; /* flag to state file was changed */static void *file_ptr; /* current file pointer location */ static void *file_append; /* added to the end of the file */static size_t file_append_size; /* how much is added to end of file */ /* Per-file resource cleanup when multiple files. */static void file_append_cleanup(void){ free(file_append); file_append = NULL; file_append_size = 0; file_updated = 0;} static void mmap_cleanup(void){ if (!mmap_failed) munmap(file_map, sb.st_size); else free(file_map); file_map = NULL;} /* ulseek, uwrite, ...: Check return value for errors. */ static off_t ulseek(off_t const offset, int const whence){ switch (whence) { case SEEK_SET: file_ptr = file_map + offset; break; case SEEK_CUR: file_ptr += offset; break; case SEEK_END: file_ptr = file_map + (sb.st_size - offset); break; } if (file_ptr < file_map) { fprintf(stderr, "lseek: seek before file\n"); return -1; } return file_ptr - file_map;} static ssize_t uwrite(void const *const buf, size_t const count){ size_t cnt = count; off_t idx = 0; file_updated = 1; if (file_ptr + count >= file_end) { off_t aoffset = (file_ptr + count) - file_end; if (aoffset > file_append_size) { file_append = realloc(file_append, aoffset); file_append_size = aoffset; } if (!file_append) { perror("write"); file_append_cleanup(); mmap_cleanup(); return -1; } if (file_ptr < file_end) { cnt = file_end - file_ptr; } else { cnt = 0; idx = aoffset - count; } } if (cnt) memcpy(file_ptr, buf, cnt); if (cnt < count) memcpy(file_append + idx, buf + cnt, count - cnt); file_ptr += count; return count;} static void * umalloc(size_t size){ void *const addr = malloc(size); if (addr == 0) { fprintf(stderr, "malloc failed: %zu bytes\n", size); file_append_cleanup(); mmap_cleanup(); return NULL; } return addr;} /* * Get the whole file as a programming convenience in order to avoid * malloc+lseek+read+free of many pieces. If successful, then mmap * avoids copying unused pieces; else just read the whole file. * Open for both read and write; new info will be appended to the file. * Use MAP_PRIVATE so that a few changes to the in-memory ElfXX_Ehdr * do not propagate to the file until an explicit overwrite at the last. * This preserves most aspects of consistency (all except .st_size) * for simultaneous readers of the file while we are appending to it. * However, multiple writers still are bad. We choose not to use * locking because it is expensive and the use case of kernel build * makes multiple writers unlikely. */static void *mmap_file(char const *fname){ /* Avoid problems if early cleanup() */ fd_map = -1; mmap_failed = 1; file_map = NULL; file_ptr = NULL; file_updated = 0; sb.st_size = 0; fd_map = open(fname, O_RDONLY); if (fd_map < 0) { perror(fname); return NULL; } if (fstat(fd_map, &sb) < 0) { perror(fname); goto out; } if (!S_ISREG(sb.st_mode)) { fprintf(stderr, "not a regular file: %s\n", fname); goto out; } file_map = mmap(0, sb.st_size, PROT_READ|PROT_WRITE, MAP_PRIVATE, fd_map, 0); if (file_map == MAP_FAILED) { mmap_failed = 1; file_map = umalloc(sb.st_size); if (!file_map) { perror(fname); goto out; } if (read(fd_map, file_map, sb.st_size) != sb.st_size) { perror(fname); free(file_map); file_map = NULL; goto out; } } else mmap_failed = 0;out: close(fd_map); fd_map = -1; file_end = file_map + sb.st_size; return file_map;} static unsigned char ideal_nop5_x86_64[5] = { 0x0f, 0x1f, 0x44, 0x00, 0x00 };static unsigned char ideal_nop5_x86_32[5] = { 0x3e, 0x8d, 0x74, 0x26, 0x00 };static unsigned char *ideal_nop; static char rel_type_nop; static int (*make_nop)(void *map, size_t const offset); static int make_nop_x86(void *map, size_t const offset){ uint32_t *ptr; unsigned char *op; /* Confirm we have 0xe8 0x0 0x0 0x0 0x0 */ ptr = map + offset; if (*ptr != 0) return -1; op = map + offset - 1; if (*op != 0xe8) return -1; /* convert to nop */ if (ulseek(offset - 1, SEEK_SET) < 0) return -1; if (uwrite(ideal_nop, 5) < 0) return -1; return 0;} static unsigned char ideal_nop4_arm_le[4] = { 0x00, 0x00, 0xa0, 0xe1 }; /* mov r0, r0 */static unsigned char ideal_nop4_arm_be[4] = { 0xe1, 0xa0, 0x00, 0x00 }; /* mov r0, r0 */static unsigned char *ideal_nop4_arm; static unsigned char bl_mcount_arm_le[4] = { 0xfe, 0xff, 0xff, 0xeb }; /* bl */static unsigned char bl_mcount_arm_be[4] = { 0xeb, 0xff, 0xff, 0xfe }; /* bl */static unsigned char *bl_mcount_arm; static unsigned char push_arm_le[4] = { 0x04, 0xe0, 0x2d, 0xe5 }; /* push {lr} */static unsigned char push_arm_be[4] = { 0xe5, 0x2d, 0xe0, 0x04 }; /* push {lr} */static unsigned char *push_arm; static unsigned char ideal_nop2_thumb_le[2] = { 0x00, 0xbf }; /* nop */static unsigned char ideal_nop2_thumb_be[2] = { 0xbf, 0x00 }; /* nop */static unsigned char *ideal_nop2_thumb; static unsigned char push_bl_mcount_thumb_le[6] = { 0x00, 0xb5, 0xff, 0xf7, 0xfe, 0xff }; /* push {lr}, bl */static unsigned char push_bl_mcount_thumb_be[6] = { 0xb5, 0x00, 0xf7, 0xff, 0xff, 0xfe }; /* push {lr}, bl */static unsigned char *push_bl_mcount_thumb; static int make_nop_arm(void *map, size_t const offset){ char *ptr; int cnt = 1; int nop_size; size_t off = offset; ptr = map + offset; if (memcmp(ptr, bl_mcount_arm, 4) == 0) { if (memcmp(ptr - 4, push_arm, 4) == 0) { off -= 4; cnt = 2; } ideal_nop = ideal_nop4_arm; nop_size = 4; } else if (memcmp(ptr - 2, push_bl_mcount_thumb, 6) == 0) { cnt = 3; nop_size = 2; off -= 2; ideal_nop = ideal_nop2_thumb; } else return -1; /* Convert to nop */ if (ulseek(off, SEEK_SET) < 0) return -1; do { if (uwrite(ideal_nop, nop_size) < 0) return -1; } while (--cnt > 0); return 0;} static unsigned char ideal_nop4_arm64[4] = {0x1f, 0x20, 0x03, 0xd5};static int make_nop_arm64(void *map, size_t const offset){ uint32_t *ptr; ptr = map + offset; /* bl <_mcount> is 0x94000000 before relocation */ if (*ptr != 0x94000000) return -1; /* Convert to nop */ if (ulseek(offset, SEEK_SET) < 0) return -1; if (uwrite(ideal_nop, 4) < 0) return -1; return 0;} static int write_file(const char *fname){ char tmp_file[strlen(fname) + 4]; size_t n; if (!file_updated) return 0; sprintf(tmp_file, "%s.rc", fname); /* * After reading the entire file into memory, delete it * and write it back, to prevent weird side effects of modifying * an object file in place. */ fd_map = open(tmp_file, O_WRONLY | O_TRUNC | O_CREAT, sb.st_mode); if (fd_map < 0) { perror(fname); return -1; } n = write(fd_map, file_map, sb.st_size); if (n != sb.st_size) { perror("write"); close(fd_map); return -1; } if (file_append_size) { n = write(fd_map, file_append, file_append_size); if (n != file_append_size) { perror("write"); close(fd_map); return -1; } } close(fd_map); if (rename(tmp_file, fname) < 0) { perror(fname); return -1; } return 0;} /* w8rev, w8nat, ...: Handle endianness. */ static uint64_t w8rev(uint64_t const x){ return ((0xff & (x >> (0 * 8))) << (7 * 8)) | ((0xff & (x >> (1 * 8))) << (6 * 8)) | ((0xff & (x >> (2 * 8))) << (5 * 8)) | ((0xff & (x >> (3 * 8))) << (4 * 8)) | ((0xff & (x >> (4 * 8))) << (3 * 8)) | ((0xff & (x >> (5 * 8))) << (2 * 8)) | ((0xff & (x >> (6 * 8))) << (1 * 8)) | ((0xff & (x >> (7 * 8))) << (0 * 8));} static uint32_t w4rev(uint32_t const x){ return ((0xff & (x >> (0 * 8))) << (3 * 8)) | ((0xff & (x >> (1 * 8))) << (2 * 8)) | ((0xff & (x >> (2 * 8))) << (1 * 8)) | ((0xff & (x >> (3 * 8))) << (0 * 8));} static uint32_t w2rev(uint16_t const x){ return ((0xff & (x >> (0 * 8))) << (1 * 8)) | ((0xff & (x >> (1 * 8))) << (0 * 8));} static uint64_t w8nat(uint64_t const x){ return x;} static uint32_t w4nat(uint32_t const x){ return x;} static uint32_t w2nat(uint16_t const x){ return x;} static uint64_t (*w8)(uint64_t);static uint32_t (*w)(uint32_t);static uint32_t (*w2)(uint16_t); /* Names of the sections that could contain calls to mcount. */static int is_mcounted_section_name(char const *const txtname){ return strncmp(".text", txtname, 5) == 0 || strcmp(".init.text", txtname) == 0 || strcmp(".ref.text", txtname) == 0 || strcmp(".sched.text", txtname) == 0 || strcmp(".spinlock.text", txtname) == 0 || strcmp(".irqentry.text", txtname) == 0 || strcmp(".softirqentry.text", txtname) == 0 || strcmp(".kprobes.text", txtname) == 0 || strcmp(".cpuidle.text", txtname) == 0;} static char const *already_has_rel_mcount = "success"; /* our work here is done! */ /* 32 bit and 64 bit are very similar */#include "recordmcount.h"#define RECORD_MCOUNT_64#include "recordmcount.h" static int arm_is_fake_mcount(Elf32_Rel const *rp){ switch (ELF32_R_TYPE(w(rp->r_info))) { case R_ARM_THM_CALL: case R_ARM_CALL: case R_ARM_PC24: return 0; } return 1;} /* 64-bit EM_MIPS has weird ELF64_Rela.r_info. * http://techpubs.sgi.com/library/manuals/4000/007-4658-001/pdf/007-4658-001.pdf * We interpret Table 29 Relocation Operation (Elf64_Rel, Elf64_Rela) [p.40] * to imply the order of the members; the spec does not say so. * typedef unsigned char Elf64_Byte; * fails on MIPS64 because their <elf.h> already has it! */ typedef uint8_t myElf64_Byte; /* Type for a 8-bit quantity. */ union mips_r_info { Elf64_Xword r_info; struct { Elf64_Word r_sym; /* Symbol index. */ myElf64_Byte r_ssym; /* Special symbol. */ myElf64_Byte r_type3; /* Third relocation. */ myElf64_Byte r_type2; /* Second relocation. */ myElf64_Byte r_type; /* First relocation. */ } r_mips;}; static uint64_t MIPS64_r_sym(Elf64_Rel const *rp){ return w(((union mips_r_info){ .r_info = rp->r_info }).r_mips.r_sym);} static void MIPS64_r_info(Elf64_Rel *const rp, unsigned sym, unsigned type){ rp->r_info = ((union mips_r_info){ .r_mips = { .r_sym = w(sym), .r_type = type } }).r_info;} static int do_file(char const *const fname){ unsigned int reltype = 0; Elf32_Ehdr *ehdr; int rc = -1; ehdr = mmap_file(fname); if (!ehdr) goto out; w = w4nat; w2 = w2nat; w8 = w8nat; switch (ehdr->e_ident[EI_DATA]) { static unsigned int const endian = 1; default: fprintf(stderr, "unrecognized ELF data encoding %d: %s\n", ehdr->e_ident[EI_DATA], fname); goto out; case ELFDATA2LSB: if (*(unsigned char const *)&endian != 1) { /* main() is big endian, file.o is little endian. */ w = w4rev; w2 = w2rev; w8 = w8rev; } ideal_nop4_arm = ideal_nop4_arm_le; bl_mcount_arm = bl_mcount_arm_le; push_arm = push_arm_le; ideal_nop2_thumb = ideal_nop2_thumb_le; push_bl_mcount_thumb = push_bl_mcount_thumb_le;Lines 1–500 of 663. 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// SPDX-License-Identifier: GPL-2.0-only /* * recordmcount.c: construct a table of the locations of calls to 'mcount' * so that ftrace can find them quickly. * Copyright 2009 John F. Reiser <jreiser@BitWagon.com>. All rights reserved. * * Restructured to fit Linux format, as well as other updates: * Copyright 2010 Steven Rostedt <srostedt@redhat.com>, Red Hat Inc. */ /* * Strategy: alter the .o file in-place. * * Append a new STRTAB that has the new section names, followed by a new array * ElfXX_Shdr[] that has the new section headers, followed by the section * contents for __mcount_loc and its relocations. The old shstrtab strings, * and the old ElfXX_Shdr[] array, remain as "garbage" (commonly, a couple * kilobytes.) Subsequent processing by /bin/ld (or the kernel module loader) * will ignore the garbage regions, because they are not designated by the * new .e_shoff nor the new ElfXX_Shdr[]. [In order to remove the garbage, * then use "ld -r" to create a new file that omits the garbage.] */ #include <sys/types.h> #include <sys/mman.h> #include <sys/stat.h> #include <getopt.h> #include <elf.h> #include <fcntl.h> #include <stdio.h> #include <stdlib.h> #include <string.h> #include <unistd.h> #ifndef EM_AARCH64 #define EM_AARCH64 183 #define R_AARCH64_NONE 0 #define R_AARCH64_ABS64 257 #endif #define R_ARM_PC24 1 #define R_ARM_THM_CALL 10 #define R_ARM_CALL 28 static int fd_map; /* File descriptor for file being modified. */ static int mmap_failed; /* Boolean flag. */ static char gpfx; /* prefix for global symbol name (sometimes '_') */ static struct stat sb; /* Remember .st_size, etc. */ static const char *altmcount; /* alternate mcount symbol name */ static int warn_on_notrace_sect; /* warn when section has mcount not being recorded */ static void *file_map; /* pointer of the mapped file */ static void *file_end; /* pointer to the end of the mapped file */ static int file_updated; /* flag to state file was changed */ static void *file_ptr; /* current file pointer location */ static void *file_append; /* added to the end of the file */ static size_t file_append_size; /* how much is added to end of file */ /* Per-file resource cleanup when multiple files. */ static void file_append_cleanup(void) { free(file_append); file_append = NULL; file_append_size = 0; file_updated = 0; } static void mmap_cleanup(void) { if (!mmap_failed) munmap(file_map, sb.st_size); else free(file_map); file_map = NULL; } /* ulseek, uwrite, ...: Check return value for errors. */ static off_t ulseek(off_t const offset, int const whence) { switch (whence) { case SEEK_SET: file_ptr = file_map + offset; break; case SEEK_CUR: file_ptr += offset; break; case SEEK_END: file_ptr = file_map + (sb.st_size - offset); break; } if (file_ptr < file_map) { fprintf(stderr, "lseek: seek before file\n"); return -1; } return file_ptr - file_map; } static ssize_t uwrite(void const *const buf, size_t const count) { size_t cnt = count; off_t idx = 0; file_updated = 1; if (file_ptr + count >= file_end) { off_t aoffset = (file_ptr + count) - file_end; if (aoffset > file_append_size) { file_append = realloc(file_append, aoffset); file_append_size = aoffset; } if (!file_append) { perror("write"); file_append_cleanup(); mmap_cleanup(); return -1; } if (file_ptr < file_end) { cnt = file_end - file_ptr; } else { cnt = 0; idx = aoffset - count; } } if (cnt) memcpy(file_ptr, buf, cnt); if (cnt < count) memcpy(file_append + idx, buf + cnt, count - cnt); file_ptr += count; return count; } static void * umalloc(size_t size) { void *const addr = malloc(size); if (addr == 0) { fprintf(stderr, "malloc failed: %zu bytes\n", size); file_append_cleanup(); mmap_cleanup(); return NULL; } return addr; } /* * Get the whole file as a programming convenience in order to avoid * malloc+lseek+read+free of many pieces. If successful, then mmap * avoids copying unused pieces; else just read the whole file. * Open for both read and write; new info will be appended to the file. * Use MAP_PRIVATE so that a few changes to the in-memory ElfXX_Ehdr * do not propagate to the file until an explicit overwrite at the last. * This preserves most aspects of consistency (all except .st_size) * for simultaneous readers of the file while we are appending to it. * However, multiple writers still are bad. We choose not to use * locking because it is expensive and the use case of kernel build * makes multiple writers unlikely. */ static void *mmap_file(char const *fname) { /* Avoid problems if early cleanup() */ fd_map = -1; mmap_failed = 1; file_map = NULL; file_ptr = NULL; file_updated = 0; sb.st_size = 0; fd_map = open(fname, O_RDONLY); if (fd_map < 0) { perror(fname); return NULL; } if (fstat(fd_map, &sb) < 0) { perror(fname); goto out; } if (!S_ISREG(sb.st_mode)) { fprintf(stderr, "not a regular file: %s\n", fname); goto out; } file_map = mmap(0, sb.st_size, PROT_READ|PROT_WRITE, MAP_PRIVATE, fd_map, 0); if (file_map == MAP_FAILED) { mmap_failed = 1; file_map = umalloc(sb.st_size); if (!file_map) { perror(fname); goto out; } if (read(fd_map, file_map, sb.st_size) != sb.st_size) { perror(fname); free(file_map); file_map = NULL; goto out; } } else mmap_failed = 0; out: close(fd_map); fd_map = -1; file_end = file_map + sb.st_size; return file_map; } static unsigned char ideal_nop5_x86_64[5] = { 0x0f, 0x1f, 0x44, 0x00, 0x00 }; static unsigned char ideal_nop5_x86_32[5] = { 0x3e, 0x8d, 0x74, 0x26, 0x00 }; static unsigned char *ideal_nop; static char rel_type_nop; static int (*make_nop)(void *map, size_t const offset); static int make_nop_x86(void *map, size_t const offset) { uint32_t *ptr; unsigned char *op; /* Confirm we have 0xe8 0x0 0x0 0x0 0x0 */ ptr = map + offset; if (*ptr != 0) return -1; op = map + offset - 1; if (*op != 0xe8) return -1; /* convert to nop */ if (ulseek(offset - 1, SEEK_SET) < 0) return -1; if (uwrite(ideal_nop, 5) < 0) return -1; return 0; } static unsigned char ideal_nop4_arm_le[4] = { 0x00, 0x00, 0xa0, 0xe1 }; /* mov r0, r0 */ static unsigned char ideal_nop4_arm_be[4] = { 0xe1, 0xa0, 0x00, 0x00 }; /* mov r0, r0 */ static unsigned char *ideal_nop4_arm; static unsigned char bl_mcount_arm_le[4] = { 0xfe, 0xff, 0xff, 0xeb }; /* bl */ static unsigned char bl_mcount_arm_be[4] = { 0xeb, 0xff, 0xff, 0xfe }; /* bl */ static unsigned char *bl_mcount_arm; static unsigned char push_arm_le[4] = { 0x04, 0xe0, 0x2d, 0xe5 }; /* push {lr} */ static unsigned char push_arm_be[4] = { 0xe5, 0x2d, 0xe0, 0x04 }; /* push {lr} */ static unsigned char *push_arm; static unsigned char ideal_nop2_thumb_le[2] = { 0x00, 0xbf }; /* nop */ static unsigned char ideal_nop2_thumb_be[2] = { 0xbf, 0x00 }; /* nop */ static unsigned char *ideal_nop2_thumb; static unsigned char push_bl_mcount_thumb_le[6] = { 0x00, 0xb5, 0xff, 0xf7, 0xfe, 0xff }; /* push {lr}, bl */ static unsigned char push_bl_mcount_thumb_be[6] = { 0xb5, 0x00, 0xf7, 0xff, 0xff, 0xfe }; /* push {lr}, bl */ static unsigned char *push_bl_mcount_thumb; static int make_nop_arm(void *map, size_t const offset) { char *ptr; int cnt = 1; int nop_size; size_t off = offset; ptr = map + offset; if (memcmp(ptr, bl_mcount_arm, 4) == 0) { if (memcmp(ptr - 4, push_arm, 4) == 0) { off -= 4; cnt = 2; } ideal_nop = ideal_nop4_arm; nop_size = 4; } else if (memcmp(ptr - 2, push_bl_mcount_thumb, 6) == 0) { cnt = 3; nop_size = 2; off -= 2; ideal_nop = ideal_nop2_thumb; } else return -1; /* Convert to nop */ if (ulseek(off, SEEK_SET) < 0) return -1; do { if (uwrite(ideal_nop, nop_size) < 0) return -1; } while (--cnt > 0); return 0; } static unsigned char ideal_nop4_arm64[4] = {0x1f, 0x20, 0x03, 0xd5}; static int make_nop_arm64(void *map, size_t const offset) { uint32_t *ptr; ptr = map + offset; /* bl <_mcount> is 0x94000000 before relocation */ if (*ptr != 0x94000000) return -1; /* Convert to nop */ if (ulseek(offset, SEEK_SET) < 0) return -1; if (uwrite(ideal_nop, 4) < 0) return -1; return 0; } static int write_file(const char *fname) { char tmp_file[strlen(fname) + 4]; size_t n; if (!file_updated) return 0; sprintf(tmp_file, "%s.rc", fname); /* * After reading the entire file into memory, delete it * and write it back, to prevent weird side effects of modifying * an object file in place. */ fd_map = open(tmp_file, O_WRONLY | O_TRUNC | O_CREAT, sb.st_mode); if (fd_map < 0) { perror(fname); return -1; } n = write(fd_map, file_map, sb.st_size); if (n != sb.st_size) { perror("write"); close(fd_map); return -1; } if (file_append_size) { n = write(fd_map, file_append, file_append_size); if (n != file_append_size) { perror("write"); close(fd_map); return -1; } } close(fd_map); if (rename(tmp_file, fname) < 0) { perror(fname); return -1; } return 0; } /* w8rev, w8nat, ...: Handle endianness. */ static uint64_t w8rev(uint64_t const x) { return ((0xff & (x >> (0 * 8))) << (7 * 8)) | ((0xff & (x >> (1 * 8))) << (6 * 8)) | ((0xff & (x >> (2 * 8))) << (5 * 8)) | ((0xff & (x >> (3 * 8))) << (4 * 8)) | ((0xff & (x >> (4 * 8))) << (3 * 8)) | ((0xff & (x >> (5 * 8))) << (2 * 8)) | ((0xff & (x >> (6 * 8))) << (1 * 8)) | ((0xff & (x >> (7 * 8))) << (0 * 8)); } static uint32_t w4rev(uint32_t const x) { return ((0xff & (x >> (0 * 8))) << (3 * 8)) | ((0xff & (x >> (1 * 8))) << (2 * 8)) | ((0xff & (x >> (2 * 8))) << (1 * 8)) | ((0xff & (x >> (3 * 8))) << (0 * 8)); } static uint32_t w2rev(uint16_t const x) { return ((0xff & (x >> (0 * 8))) << (1 * 8)) | ((0xff & (x >> (1 * 8))) << (0 * 8)); } static uint64_t w8nat(uint64_t const x) { return x; } static uint32_t w4nat(uint32_t const x) { return x; } static uint32_t w2nat(uint16_t const x) { return x; } static uint64_t (*w8)(uint64_t); static uint32_t (*w)(uint32_t); static uint32_t (*w2)(uint16_t); /* Names of the sections that could contain calls to mcount. */ static int is_mcounted_section_name(char const *const txtname) { return strncmp(".text", txtname, 5) == 0 || strcmp(".init.text", txtname) == 0 || strcmp(".ref.text", txtname) == 0 || strcmp(".sched.text", txtname) == 0 || strcmp(".spinlock.text", txtname) == 0 || strcmp(".irqentry.text", txtname) == 0 || strcmp(".softirqentry.text", txtname) == 0 || strcmp(".kprobes.text", txtname) == 0 || strcmp(".cpuidle.text", txtname) == 0; } static char const *already_has_rel_mcount = "success"; /* our work here is done! */ /* 32 bit and 64 bit are very similar */ #include "recordmcount.h" #define RECORD_MCOUNT_64 #include "recordmcount.h" static int arm_is_fake_mcount(Elf32_Rel const *rp) { switch (ELF32_R_TYPE(w(rp->r_info))) { case R_ARM_THM_CALL: case R_ARM_CALL: case R_ARM_PC24: return 0; } return 1; } /* 64-bit EM_MIPS has weird ELF64_Rela.r_info. * http://techpubs.sgi.com/library/manuals/4000/007-4658-001/pdf/007-4658-001.pdf * We interpret Table 29 Relocation Operation (Elf64_Rel, Elf64_Rela) [p.40] * to imply the order of the members; the spec does not say so. * typedef unsigned char Elf64_Byte; * fails on MIPS64 because their <elf.h> already has it! */ typedef uint8_t myElf64_Byte; /* Type for a 8-bit quantity. */ union mips_r_info { Elf64_Xword r_info; struct { Elf64_Word r_sym; /* Symbol index. */ myElf64_Byte r_ssym; /* Special symbol. */ myElf64_Byte r_type3; /* Third relocation. */ myElf64_Byte r_type2; /* Second relocation. */ myElf64_Byte r_type; /* First relocation. */ } r_mips; }; static uint64_t MIPS64_r_sym(Elf64_Rel const *rp) { return w(((union mips_r_info){ .r_info = rp->r_info }).r_mips.r_sym); } static void MIPS64_r_info(Elf64_Rel *const rp, unsigned sym, unsigned type) { rp->r_info = ((union mips_r_info){ .r_mips = { .r_sym = w(sym), .r_type = type } }).r_info; } static int do_file(char const *const fname) { unsigned int reltype = 0; Elf32_Ehdr *ehdr; int rc = -1; ehdr = mmap_file(fname); if (!ehdr) goto out; w = w4nat; w2 = w2nat; w8 = w8nat; switch (ehdr->e_ident[EI_DATA]) { static unsigned int const endian = 1; default: fprintf(stderr, "unrecognized ELF data encoding %d: %s\n", ehdr->e_ident[EI_DATA], fname); goto out; case ELFDATA2LSB: if (*(unsigned char const *)&endian != 1) { /* main() is big endian, file.o is little endian. */ w = w4rev; w2 = w2rev; w8 = w8rev; } ideal_nop4_arm = ideal_nop4_arm_le; bl_mcount_arm = bl_mcount_arm_le; push_arm = push_arm_le; ideal_nop2_thumb = ideal_nop2_thumb_le; push_bl_mcount_thumb = push_bl_mcount_thumb_le;