Commit | Line | Data |
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6f121e54 AL |
1 | /* |
2 | * This file is included twice from vdso2c.c. It generates code for 32-bit | |
3 | * and 64-bit vDSOs. We need both for 64-bit builds, since 32-bit vDSOs | |
4 | * are built for 32-bit userspace. | |
5 | */ | |
6 | ||
01156183 | 7 | static void GOFUNC(void *addr, size_t len, FILE *outfile, const char *name) |
6f121e54 AL |
8 | { |
9 | int found_load = 0; | |
10 | unsigned long load_size = -1; /* Work around bogus warning */ | |
11 | unsigned long data_size; | |
12 | Elf_Ehdr *hdr = (Elf_Ehdr *)addr; | |
13 | int i; | |
14 | unsigned long j; | |
15 | Elf_Shdr *symtab_hdr = NULL, *strtab_hdr, *secstrings_hdr, | |
16 | *alt_sec = NULL; | |
17 | Elf_Dyn *dyn = 0, *dyn_end = 0; | |
18 | const char *secstrings; | |
19 | uint64_t syms[NSYMS] = {}; | |
20 | ||
e0bf7b86 AL |
21 | uint64_t fake_sections_value = 0, fake_sections_size = 0; |
22 | ||
bdfb9bcc | 23 | Elf_Phdr *pt = (Elf_Phdr *)(addr + GET_LE(&hdr->e_phoff)); |
6f121e54 AL |
24 | |
25 | /* Walk the segment table. */ | |
bdfb9bcc PA |
26 | for (i = 0; i < GET_LE(&hdr->e_phnum); i++) { |
27 | if (GET_LE(&pt[i].p_type) == PT_LOAD) { | |
6f121e54 AL |
28 | if (found_load) |
29 | fail("multiple PT_LOAD segs\n"); | |
30 | ||
bdfb9bcc PA |
31 | if (GET_LE(&pt[i].p_offset) != 0 || |
32 | GET_LE(&pt[i].p_vaddr) != 0) | |
6f121e54 AL |
33 | fail("PT_LOAD in wrong place\n"); |
34 | ||
bdfb9bcc | 35 | if (GET_LE(&pt[i].p_memsz) != GET_LE(&pt[i].p_filesz)) |
6f121e54 AL |
36 | fail("cannot handle memsz != filesz\n"); |
37 | ||
bdfb9bcc | 38 | load_size = GET_LE(&pt[i].p_memsz); |
6f121e54 | 39 | found_load = 1; |
bdfb9bcc PA |
40 | } else if (GET_LE(&pt[i].p_type) == PT_DYNAMIC) { |
41 | dyn = addr + GET_LE(&pt[i].p_offset); | |
42 | dyn_end = addr + GET_LE(&pt[i].p_offset) + | |
43 | GET_LE(&pt[i].p_memsz); | |
6f121e54 AL |
44 | } |
45 | } | |
46 | if (!found_load) | |
47 | fail("no PT_LOAD seg\n"); | |
48 | data_size = (load_size + 4095) / 4096 * 4096; | |
49 | ||
50 | /* Walk the dynamic table */ | |
c191920f | 51 | for (i = 0; dyn + i < dyn_end && |
bdfb9bcc PA |
52 | GET_LE(&dyn[i].d_tag) != DT_NULL; i++) { |
53 | typeof(dyn[i].d_tag) tag = GET_LE(&dyn[i].d_tag); | |
add4eed0 AL |
54 | if (tag == DT_REL || tag == DT_RELSZ || |
55 | tag == DT_RELENT || tag == DT_TEXTREL) | |
6f121e54 AL |
56 | fail("vdso image contains dynamic relocations\n"); |
57 | } | |
58 | ||
59 | /* Walk the section table */ | |
bdfb9bcc PA |
60 | secstrings_hdr = addr + GET_LE(&hdr->e_shoff) + |
61 | GET_LE(&hdr->e_shentsize)*GET_LE(&hdr->e_shstrndx); | |
62 | secstrings = addr + GET_LE(&secstrings_hdr->sh_offset); | |
63 | for (i = 0; i < GET_LE(&hdr->e_shnum); i++) { | |
64 | Elf_Shdr *sh = addr + GET_LE(&hdr->e_shoff) + | |
65 | GET_LE(&hdr->e_shentsize) * i; | |
66 | if (GET_LE(&sh->sh_type) == SHT_SYMTAB) | |
6f121e54 AL |
67 | symtab_hdr = sh; |
68 | ||
bdfb9bcc | 69 | if (!strcmp(secstrings + GET_LE(&sh->sh_name), |
c191920f | 70 | ".altinstructions")) |
6f121e54 AL |
71 | alt_sec = sh; |
72 | } | |
73 | ||
01156183 | 74 | if (!symtab_hdr) |
6f121e54 | 75 | fail("no symbol table\n"); |
6f121e54 | 76 | |
bdfb9bcc PA |
77 | strtab_hdr = addr + GET_LE(&hdr->e_shoff) + |
78 | GET_LE(&hdr->e_shentsize) * GET_LE(&symtab_hdr->sh_link); | |
6f121e54 AL |
79 | |
80 | /* Walk the symbol table */ | |
c191920f | 81 | for (i = 0; |
bdfb9bcc | 82 | i < GET_LE(&symtab_hdr->sh_size) / GET_LE(&symtab_hdr->sh_entsize); |
add4eed0 | 83 | i++) { |
6f121e54 | 84 | int k; |
bdfb9bcc PA |
85 | Elf_Sym *sym = addr + GET_LE(&symtab_hdr->sh_offset) + |
86 | GET_LE(&symtab_hdr->sh_entsize) * i; | |
87 | const char *name = addr + GET_LE(&strtab_hdr->sh_offset) + | |
88 | GET_LE(&sym->st_name); | |
e0bf7b86 | 89 | |
6f121e54 AL |
90 | for (k = 0; k < NSYMS; k++) { |
91 | if (!strcmp(name, required_syms[k])) { | |
92 | if (syms[k]) { | |
93 | fail("duplicate symbol %s\n", | |
94 | required_syms[k]); | |
95 | } | |
bdfb9bcc | 96 | syms[k] = GET_LE(&sym->st_value); |
6f121e54 AL |
97 | } |
98 | } | |
e0bf7b86 AL |
99 | |
100 | if (!strcmp(name, "vdso_fake_sections")) { | |
101 | if (fake_sections_value) | |
102 | fail("duplicate vdso_fake_sections\n"); | |
103 | fake_sections_value = GET_LE(&sym->st_value); | |
104 | fake_sections_size = GET_LE(&sym->st_size); | |
105 | } | |
6f121e54 AL |
106 | } |
107 | ||
18d0a6fd AL |
108 | /* Validate mapping addresses. */ |
109 | for (i = 0; i < sizeof(special_pages) / sizeof(special_pages[0]); i++) { | |
110 | if (!syms[i]) | |
111 | continue; /* The mapping isn't used; ignore it. */ | |
112 | ||
113 | if (syms[i] % 4096) | |
114 | fail("%s must be a multiple of 4096\n", | |
115 | required_syms[i]); | |
116 | if (syms[i] < data_size) | |
117 | fail("%s must be after the text mapping\n", | |
118 | required_syms[i]); | |
119 | if (syms[sym_end_mapping] < syms[i] + 4096) | |
120 | fail("%s overruns end_mapping\n", required_syms[i]); | |
121 | } | |
122 | if (syms[sym_end_mapping] % 4096) | |
123 | fail("end_mapping must be a multiple of 4096\n"); | |
124 | ||
e0bf7b86 AL |
125 | /* Remove sections or use fakes */ |
126 | if (fake_sections_size % sizeof(Elf_Shdr)) | |
127 | fail("vdso_fake_sections size is not a multiple of %ld\n", | |
128 | (long)sizeof(Elf_Shdr)); | |
129 | PUT_LE(&hdr->e_shoff, fake_sections_value); | |
130 | PUT_LE(&hdr->e_shentsize, fake_sections_value ? sizeof(Elf_Shdr) : 0); | |
131 | PUT_LE(&hdr->e_shnum, fake_sections_size / sizeof(Elf_Shdr)); | |
132 | PUT_LE(&hdr->e_shstrndx, SHN_UNDEF); | |
6f121e54 AL |
133 | |
134 | if (!name) { | |
135 | fwrite(addr, load_size, 1, outfile); | |
01156183 | 136 | return; |
6f121e54 AL |
137 | } |
138 | ||
139 | fprintf(outfile, "/* AUTOMATICALLY GENERATED -- DO NOT EDIT */\n\n"); | |
140 | fprintf(outfile, "#include <linux/linkage.h>\n"); | |
141 | fprintf(outfile, "#include <asm/page_types.h>\n"); | |
142 | fprintf(outfile, "#include <asm/vdso.h>\n"); | |
143 | fprintf(outfile, "\n"); | |
144 | fprintf(outfile, | |
145 | "static unsigned char raw_data[%lu] __page_aligned_data = {", | |
146 | data_size); | |
147 | for (j = 0; j < load_size; j++) { | |
148 | if (j % 10 == 0) | |
149 | fprintf(outfile, "\n\t"); | |
150 | fprintf(outfile, "0x%02X, ", (int)((unsigned char *)addr)[j]); | |
151 | } | |
152 | fprintf(outfile, "\n};\n\n"); | |
153 | ||
154 | fprintf(outfile, "static struct page *pages[%lu];\n\n", | |
155 | data_size / 4096); | |
156 | ||
157 | fprintf(outfile, "const struct vdso_image %s = {\n", name); | |
158 | fprintf(outfile, "\t.data = raw_data,\n"); | |
159 | fprintf(outfile, "\t.size = %lu,\n", data_size); | |
a62c34bd AL |
160 | fprintf(outfile, "\t.text_mapping = {\n"); |
161 | fprintf(outfile, "\t\t.name = \"[vdso]\",\n"); | |
162 | fprintf(outfile, "\t\t.pages = pages,\n"); | |
163 | fprintf(outfile, "\t},\n"); | |
6f121e54 AL |
164 | if (alt_sec) { |
165 | fprintf(outfile, "\t.alt = %lu,\n", | |
bdfb9bcc | 166 | (unsigned long)GET_LE(&alt_sec->sh_offset)); |
6f121e54 | 167 | fprintf(outfile, "\t.alt_len = %lu,\n", |
bdfb9bcc | 168 | (unsigned long)GET_LE(&alt_sec->sh_size)); |
6f121e54 AL |
169 | } |
170 | for (i = 0; i < NSYMS; i++) { | |
171 | if (syms[i]) | |
172 | fprintf(outfile, "\t.sym_%s = 0x%" PRIx64 ",\n", | |
173 | required_syms[i], syms[i]); | |
174 | } | |
175 | fprintf(outfile, "};\n"); | |
6f121e54 | 176 | } |