src/gallium/drivers/radeon/radeon_elf_util.c

   1 /*
   2  * Copyright 2014 Advanced Micro Devices, Inc.
   3  *
   4  * Permission is hereby granted, free of charge, to any person obtaining a
   5  * copy of this software and associated documentation files (the "Software"),
   6  * to deal in the Software without restriction, including without limitation
   7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
   8  * and/or sell copies of the Software, and to permit persons to whom the
   9  * Software is furnished to do so, subject to the following conditions:
  10  *
  11  * The above copyright notice and this permission notice (including the next
  12  * paragraph) shall be included in all copies or substantial portions of the
  13  * Software.
  14  *
  15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  18  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  20  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  21  * SOFTWARE.
  22  *
  23  * Authors: Tom Stellard <thomas.stellard@amd.com>
  24  *
  25  */
  26
  27 #include "radeon_elf_util.h"
  28 #include "r600_pipe_common.h"
  29
  30 #include "util/u_memory.h"
  31
  32 #include <gelf.h>
  33 #include <libelf.h>
  34 #include <stdio.h>
  35
  36 static void parse_symbol_table(Elf_Data *symbol_table_data,
  37                                 const GElf_Shdr *symbol_table_header,
  38                                 struct radeon_shader_binary *binary)
  39 {
  40         GElf_Sym symbol;
  41         unsigned i = 0;
  42         unsigned symbol_count =
  43                 symbol_table_header->sh_size / symbol_table_header->sh_entsize;
  44
  45         /* We are over allocating this list, because symbol_count gives the
  46          * total number of symbols, and we will only be filling the list
  47          * with offsets of global symbols.  The memory savings from
  48          * allocating the correct size of this list will be small, and
  49          * I don't think it is worth the cost of pre-computing the number
  50          * of global symbols.
  51          */
  52         binary->global_symbol_offsets = CALLOC(symbol_count, sizeof(uint64_t));
  53
  54         while (gelf_getsym(symbol_table_data, i++, &symbol)) {
  55                 unsigned i;
  56                 if (GELF_ST_BIND(symbol.st_info) != STB_GLOBAL) {
  57                         continue;
  58                 }
  59
  60                 binary->global_symbol_offsets[binary->global_symbol_count] =
  61                                         symbol.st_value;
  62
  63                 /* Sort the list using bubble sort.  This list will usually
  64                  * be small. */
  65                 for (i = binary->global_symbol_count; i > 0; --i) {
  66                         uint64_t lhs = binary->global_symbol_offsets[i - 1];
  67                         uint64_t rhs = binary->global_symbol_offsets[i];
  68                         if (lhs < rhs) {
  69                                 break;
  70                         }
  71                         binary->global_symbol_offsets[i] = lhs;
  72                         binary->global_symbol_offsets[i - 1] = rhs;
  73                 }
  74                 ++binary->global_symbol_count;
  75         }
  76 }
  77
  78 void radeon_elf_read(const char *elf_data, unsigned elf_size,
  79                                         struct radeon_shader_binary *binary,
  80                                         unsigned debug)
  81 {
  82         char *elf_buffer;
  83         Elf *elf;
  84         Elf_Scn *section = NULL;
  85         size_t section_str_index;
  86
  87         /* One of the libelf implementations
  88          * (http://www.mr511.de/software/english.htm) requires calling
  89          * elf_version() before elf_memory().
  90          */
  91         elf_version(EV_CURRENT);
  92         elf_buffer = MALLOC(elf_size);
  93         memcpy(elf_buffer, elf_data, elf_size);
  94
  95         elf = elf_memory(elf_buffer, elf_size);
  96
  97         elf_getshdrstrndx(elf, &section_str_index);
  98         binary->disassembled = 0;
  99
 100         while ((section = elf_nextscn(elf, section))) {
 101                 const char *name;
 102                 Elf_Data *section_data = NULL;
 103                 GElf_Shdr section_header;
 104                 if (gelf_getshdr(section, &section_header) != &section_header) {
 105                         fprintf(stderr, "Failed to read ELF section header\n");
 106                         return;
 107                 }
 108                 name = elf_strptr(elf, section_str_index, section_header.sh_name);
 109                 if (!strcmp(name, ".text")) {
 110                         section_data = elf_getdata(section, section_data);
 111                         binary->code_size = section_data->d_size;
 112                         binary->code = MALLOC(binary->code_size * sizeof(unsigned char));
 113                         memcpy(binary->code, section_data->d_buf, binary->code_size);
 114                 } else if (!strcmp(name, ".AMDGPU.config")) {
 115                         section_data = elf_getdata(section, section_data);
 116                         binary->config_size = section_data->d_size;
 117                         binary->config = MALLOC(binary->config_size * sizeof(unsigned char));
 118                         memcpy(binary->config, section_data->d_buf, binary->config_size);
 119                 } else if (debug && !strcmp(name, ".AMDGPU.disasm")) {
 120                         binary->disassembled = 1;
 121                         section_data = elf_getdata(section, section_data);
 122                         fprintf(stderr, "\nShader Disassembly:\n\n");
 123                         fprintf(stderr, "%.*s\n", (int)section_data->d_size,
 124                                                   (char *)section_data->d_buf);
 125                 } else if (!strncmp(name, ".rodata", 7)) {
 126                         section_data = elf_getdata(section, section_data);
 127                         binary->rodata_size = section_data->d_size;
 128                         binary->rodata = MALLOC(binary->rodata_size * sizeof(unsigned char));
 129                         memcpy(binary->rodata, section_data->d_buf, binary->rodata_size);
 130                 } else if (!strncmp(name, ".symtab", 7)) {
 131                         section_data = elf_getdata(section, section_data);
 132                         parse_symbol_table(section_data, &section_header, binary);
 133                 }
 134         }
 135
 136         if (elf){
 137                 elf_end(elf);
 138         }
 139         FREE(elf_buffer);
 140
 141         /* Cache the config size per symbol */
 142         if (binary->global_symbol_count) {
 143                 binary->config_size_per_symbol =
 144                         binary->config_size / binary->global_symbol_count;
 145         } else {
 146                 binary->global_symbol_count = 1;
 147                 binary->config_size_per_symbol = binary->config_size;
 148         }
 149 }
 150
 151 const unsigned char *radeon_shader_binary_config_start(
 152         const struct radeon_shader_binary *binary,
 153         uint64_t symbol_offset)
 154 {
 155         unsigned i;
 156         for (i = 0; i < binary->global_symbol_count; ++i) {
 157                 if (binary->global_symbol_offsets[i] == symbol_offset) {
 158                         unsigned offset = i * binary->config_size_per_symbol;
 159                         return binary->config + offset;
 160                 }
 161         }
 162         return binary->config;
 163 }
 164
 165 void radeon_shader_binary_free_members(struct radeon_shader_binary *binary) {
 166         FREE(binary->code);
 167         FREE(binary->config);
 168         FREE(binary->rodata);
 169 }