scripts/coccinelle: find constant additions that could be bit ors
[linux-3.10.git] / scripts / sortextable.h
1 /*
2  * sortextable.h
3  *
4  * Copyright 2011 - 2012 Cavium, Inc.
5  *
6  * Some of this code was taken out of recordmcount.h written by:
7  *
8  * Copyright 2009 John F. Reiser <jreiser@BitWagon.com>.  All rights reserved.
9  * Copyright 2010 Steven Rostedt <srostedt@redhat.com>, Red Hat Inc.
10  *
11  *
12  * Licensed under the GNU General Public License, version 2 (GPLv2).
13  */
14
15 #undef extable_ent_size
16 #undef compare_extable
17 #undef do_func
18 #undef Elf_Addr
19 #undef Elf_Ehdr
20 #undef Elf_Shdr
21 #undef Elf_Rel
22 #undef Elf_Rela
23 #undef Elf_Sym
24 #undef ELF_R_SYM
25 #undef Elf_r_sym
26 #undef ELF_R_INFO
27 #undef Elf_r_info
28 #undef ELF_ST_BIND
29 #undef ELF_ST_TYPE
30 #undef fn_ELF_R_SYM
31 #undef fn_ELF_R_INFO
32 #undef uint_t
33 #undef _r
34 #undef _w
35
36 #ifdef SORTEXTABLE_64
37 # define extable_ent_size       16
38 # define compare_extable        compare_extable_64
39 # define do_func                do64
40 # define Elf_Addr               Elf64_Addr
41 # define Elf_Ehdr               Elf64_Ehdr
42 # define Elf_Shdr               Elf64_Shdr
43 # define Elf_Rel                Elf64_Rel
44 # define Elf_Rela               Elf64_Rela
45 # define Elf_Sym                Elf64_Sym
46 # define ELF_R_SYM              ELF64_R_SYM
47 # define Elf_r_sym              Elf64_r_sym
48 # define ELF_R_INFO             ELF64_R_INFO
49 # define Elf_r_info             Elf64_r_info
50 # define ELF_ST_BIND            ELF64_ST_BIND
51 # define ELF_ST_TYPE            ELF64_ST_TYPE
52 # define fn_ELF_R_SYM           fn_ELF64_R_SYM
53 # define fn_ELF_R_INFO          fn_ELF64_R_INFO
54 # define uint_t                 uint64_t
55 # define _r                     r8
56 # define _w                     w8
57 #else
58 # define extable_ent_size       8
59 # define compare_extable        compare_extable_32
60 # define do_func                do32
61 # define Elf_Addr               Elf32_Addr
62 # define Elf_Ehdr               Elf32_Ehdr
63 # define Elf_Shdr               Elf32_Shdr
64 # define Elf_Rel                Elf32_Rel
65 # define Elf_Rela               Elf32_Rela
66 # define Elf_Sym                Elf32_Sym
67 # define ELF_R_SYM              ELF32_R_SYM
68 # define Elf_r_sym              Elf32_r_sym
69 # define ELF_R_INFO             ELF32_R_INFO
70 # define Elf_r_info             Elf32_r_info
71 # define ELF_ST_BIND            ELF32_ST_BIND
72 # define ELF_ST_TYPE            ELF32_ST_TYPE
73 # define fn_ELF_R_SYM           fn_ELF32_R_SYM
74 # define fn_ELF_R_INFO          fn_ELF32_R_INFO
75 # define uint_t                 uint32_t
76 # define _r                     r
77 # define _w                     w
78 #endif
79
80 static int compare_extable(const void *a, const void *b)
81 {
82         Elf_Addr av = _r(a);
83         Elf_Addr bv = _r(b);
84
85         if (av < bv)
86                 return -1;
87         if (av > bv)
88                 return 1;
89         return 0;
90 }
91
92 static void
93 do_func(Elf_Ehdr *ehdr, char const *const fname, table_sort_t custom_sort)
94 {
95         Elf_Shdr *shdr;
96         Elf_Shdr *shstrtab_sec;
97         Elf_Shdr *strtab_sec = NULL;
98         Elf_Shdr *symtab_sec = NULL;
99         Elf_Shdr *extab_sec = NULL;
100         Elf_Sym *sym;
101         Elf_Sym *sort_needed_sym;
102         Elf_Shdr *sort_needed_sec;
103         Elf_Rel *relocs = NULL;
104         int relocs_size;
105         uint32_t *sort_done_location;
106         const char *secstrtab;
107         const char *strtab;
108         char *extab_image;
109         int extab_index = 0;
110         int i;
111         int idx;
112
113         shdr = (Elf_Shdr *)((char *)ehdr + _r(&ehdr->e_shoff));
114         shstrtab_sec = shdr + r2(&ehdr->e_shstrndx);
115         secstrtab = (const char *)ehdr + _r(&shstrtab_sec->sh_offset);
116         for (i = 0; i < r2(&ehdr->e_shnum); i++) {
117                 idx = r(&shdr[i].sh_name);
118                 if (strcmp(secstrtab + idx, "__ex_table") == 0) {
119                         extab_sec = shdr + i;
120                         extab_index = i;
121                 }
122                 if ((r(&shdr[i].sh_type) == SHT_REL ||
123                      r(&shdr[i].sh_type) == SHT_RELA) &&
124                     r(&shdr[i].sh_info) == extab_index) {
125                         relocs = (void *)ehdr + _r(&shdr[i].sh_offset);
126                         relocs_size = _r(&shdr[i].sh_size);
127                 }
128                 if (strcmp(secstrtab + idx, ".symtab") == 0)
129                         symtab_sec = shdr + i;
130                 if (strcmp(secstrtab + idx, ".strtab") == 0)
131                         strtab_sec = shdr + i;
132         }
133         if (strtab_sec == NULL) {
134                 fprintf(stderr, "no .strtab in  file: %s\n", fname);
135                 fail_file();
136         }
137         if (symtab_sec == NULL) {
138                 fprintf(stderr, "no .symtab in  file: %s\n", fname);
139                 fail_file();
140         }
141         if (extab_sec == NULL) {
142                 fprintf(stderr, "no __ex_table in  file: %s\n", fname);
143                 fail_file();
144         }
145         strtab = (const char *)ehdr + _r(&strtab_sec->sh_offset);
146
147         extab_image = (void *)ehdr + _r(&extab_sec->sh_offset);
148
149         if (custom_sort) {
150                 custom_sort(extab_image, _r(&extab_sec->sh_size));
151         } else {
152                 int num_entries = _r(&extab_sec->sh_size) / extable_ent_size;
153                 qsort(extab_image, num_entries,
154                       extable_ent_size, compare_extable);
155         }
156         /* If there were relocations, we no longer need them. */
157         if (relocs)
158                 memset(relocs, 0, relocs_size);
159
160         /* find main_extable_sort_needed */
161         sort_needed_sym = NULL;
162         for (i = 0; i < _r(&symtab_sec->sh_size) / sizeof(Elf_Sym); i++) {
163                 sym = (void *)ehdr + _r(&symtab_sec->sh_offset);
164                 sym += i;
165                 if (ELF_ST_TYPE(sym->st_info) != STT_OBJECT)
166                         continue;
167                 idx = r(&sym->st_name);
168                 if (strcmp(strtab + idx, "main_extable_sort_needed") == 0) {
169                         sort_needed_sym = sym;
170                         break;
171                 }
172         }
173         if (sort_needed_sym == NULL) {
174                 fprintf(stderr,
175                         "no main_extable_sort_needed symbol in  file: %s\n",
176                         fname);
177                 fail_file();
178         }
179         sort_needed_sec = &shdr[r2(&sort_needed_sym->st_shndx)];
180         sort_done_location = (void *)ehdr +
181                 _r(&sort_needed_sec->sh_offset) +
182                 _r(&sort_needed_sym->st_value) -
183                 _r(&sort_needed_sec->sh_addr);
184
185 #if 1
186         printf("sort done marker at %lx\n",
187                (unsigned long)((char *)sort_done_location - (char *)ehdr));
188 #endif
189         /* We sorted it, clear the flag. */
190         w(0, sort_done_location);
191 }