1 /* $NetBSD: mdreloc.c,v 1.42 2008/04/28 20:23:04 martin Exp $ */
4 * Copyright (c) 2000 Eduardo Horvath.
5 * Copyright (c) 1999 The NetBSD Foundation, Inc.
8 * This code is derived from software contributed to The NetBSD Foundation
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in the
18 * documentation and/or other materials provided with the distribution.
20 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
21 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
22 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
23 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
24 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
25 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
26 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
27 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
28 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
29 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
30 * POSSIBILITY OF SUCH DAMAGE.
33 #include <sys/cdefs.h>
34 __FBSDID("$FreeBSD$");
36 #include <sys/param.h>
49 * The following table holds for each relocation type:
50 * - the width in bits of the memory location the relocation
51 * applies to (not currently used)
52 * - the number of bits the relocation value must be shifted to the
53 * right (i.e. discard least significant bits) to fit into
54 * the appropriate field in the instruction word.
55 * - flags indicating whether
56 * * the relocation involves a symbol
57 * * the relocation is relative to the current position
58 * * the relocation is for a GOT entry
59 * * the relocation is relative to the load address
62 #define _RF_S 0x80000000 /* Resolve symbol */
63 #define _RF_A 0x40000000 /* Use addend */
64 #define _RF_P 0x20000000 /* Location relative */
65 #define _RF_G 0x10000000 /* GOT offset */
66 #define _RF_B 0x08000000 /* Load address relative */
67 #define _RF_U 0x04000000 /* Unaligned */
68 #define _RF_X 0x02000000 /* Bare symbols, needs proc */
69 #define _RF_D 0x01000000 /* Use dynamic TLS offset */
70 #define _RF_O 0x00800000 /* Use static TLS offset */
71 #define _RF_I 0x00400000 /* Use TLS object ID */
72 #define _RF_SZ(s) (((s) & 0xff) << 8) /* memory target size */
73 #define _RF_RS(s) ( (s) & 0xff) /* right shift */
74 static const int reloc_target_flags[] = {
76 _RF_S|_RF_A| _RF_SZ(8) | _RF_RS(0), /* 8 */
77 _RF_S|_RF_A| _RF_SZ(16) | _RF_RS(0), /* 16 */
78 _RF_S|_RF_A| _RF_SZ(32) | _RF_RS(0), /* 32 */
79 _RF_S|_RF_A|_RF_P| _RF_SZ(8) | _RF_RS(0), /* DISP_8 */
80 _RF_S|_RF_A|_RF_P| _RF_SZ(16) | _RF_RS(0), /* DISP_16 */
81 _RF_S|_RF_A|_RF_P| _RF_SZ(32) | _RF_RS(0), /* DISP_32 */
82 _RF_S|_RF_A|_RF_P| _RF_SZ(32) | _RF_RS(2), /* WDISP_30 */
83 _RF_S|_RF_A|_RF_P| _RF_SZ(32) | _RF_RS(2), /* WDISP_22 */
84 _RF_S|_RF_A|_RF_X| _RF_SZ(32) | _RF_RS(10), /* HI22 */
85 _RF_S|_RF_A|_RF_X| _RF_SZ(32) | _RF_RS(0), /* 22 */
86 _RF_S|_RF_A|_RF_X| _RF_SZ(32) | _RF_RS(0), /* 13 */
87 _RF_S|_RF_A|_RF_X| _RF_SZ(32) | _RF_RS(0), /* LO10 */
88 _RF_G| _RF_SZ(32) | _RF_RS(0), /* GOT10 */
89 _RF_G| _RF_SZ(32) | _RF_RS(0), /* GOT13 */
90 _RF_G| _RF_SZ(32) | _RF_RS(10), /* GOT22 */
91 _RF_S|_RF_A|_RF_P| _RF_SZ(32) | _RF_RS(0), /* PC10 */
92 _RF_S|_RF_A|_RF_P| _RF_SZ(32) | _RF_RS(10), /* PC22 */
93 _RF_A|_RF_P| _RF_SZ(32) | _RF_RS(2), /* WPLT30 */
94 _RF_SZ(32) | _RF_RS(0), /* COPY */
95 _RF_S|_RF_A| _RF_SZ(64) | _RF_RS(0), /* GLOB_DAT */
96 _RF_SZ(32) | _RF_RS(0), /* JMP_SLOT */
97 _RF_A| _RF_B| _RF_SZ(64) | _RF_RS(0), /* RELATIVE */
98 _RF_S|_RF_A| _RF_U| _RF_SZ(32) | _RF_RS(0), /* UA_32 */
100 _RF_A| _RF_SZ(32) | _RF_RS(0), /* PLT32 */
101 _RF_A| _RF_SZ(32) | _RF_RS(10), /* HIPLT22 */
102 _RF_A| _RF_SZ(32) | _RF_RS(0), /* LOPLT10 */
103 _RF_A|_RF_P| _RF_SZ(32) | _RF_RS(0), /* PCPLT32 */
104 _RF_A|_RF_P| _RF_SZ(32) | _RF_RS(10), /* PCPLT22 */
105 _RF_A|_RF_P| _RF_SZ(32) | _RF_RS(0), /* PCPLT10 */
106 _RF_S|_RF_A|_RF_X| _RF_SZ(32) | _RF_RS(0), /* 10 */
107 _RF_S|_RF_A|_RF_X| _RF_SZ(32) | _RF_RS(0), /* 11 */
108 _RF_S|_RF_A|_RF_X| _RF_SZ(64) | _RF_RS(0), /* 64 */
109 _RF_S|_RF_A|/*extra*/ _RF_SZ(32) | _RF_RS(0), /* OLO10 */
110 _RF_S|_RF_A|_RF_X| _RF_SZ(32) | _RF_RS(42), /* HH22 */
111 _RF_S|_RF_A|_RF_X| _RF_SZ(32) | _RF_RS(32), /* HM10 */
112 _RF_S|_RF_A|_RF_X| _RF_SZ(32) | _RF_RS(10), /* LM22 */
113 _RF_S|_RF_A|_RF_P| _RF_SZ(32) | _RF_RS(42), /* PC_HH22 */
114 _RF_S|_RF_A|_RF_P| _RF_SZ(32) | _RF_RS(32), /* PC_HM10 */
115 _RF_S|_RF_A|_RF_P| _RF_SZ(32) | _RF_RS(10), /* PC_LM22 */
116 _RF_S|_RF_A|_RF_P| _RF_SZ(32) | _RF_RS(2), /* WDISP16 */
117 _RF_S|_RF_A|_RF_P| _RF_SZ(32) | _RF_RS(2), /* WDISP19 */
118 _RF_S|_RF_A| _RF_SZ(32) | _RF_RS(0), /* GLOB_JMP */
119 _RF_S|_RF_A|_RF_X| _RF_SZ(32) | _RF_RS(0), /* 7 */
120 _RF_S|_RF_A|_RF_X| _RF_SZ(32) | _RF_RS(0), /* 5 */
121 _RF_S|_RF_A|_RF_X| _RF_SZ(32) | _RF_RS(0), /* 6 */
122 _RF_S|_RF_A|_RF_P| _RF_SZ(64) | _RF_RS(0), /* DISP64 */
123 _RF_A| _RF_SZ(64) | _RF_RS(0), /* PLT64 */
124 _RF_S|_RF_A|_RF_X| _RF_SZ(32) | _RF_RS(10), /* HIX22 */
125 _RF_S|_RF_A|_RF_X| _RF_SZ(32) | _RF_RS(0), /* LOX10 */
126 _RF_S|_RF_A|_RF_X| _RF_SZ(32) | _RF_RS(22), /* H44 */
127 _RF_S|_RF_A|_RF_X| _RF_SZ(32) | _RF_RS(12), /* M44 */
128 _RF_S|_RF_A|_RF_X| _RF_SZ(32) | _RF_RS(0), /* L44 */
129 _RF_S|_RF_A| _RF_SZ(64) | _RF_RS(0), /* REGISTER */
130 _RF_S|_RF_A| _RF_U| _RF_SZ(64) | _RF_RS(0), /* UA64 */
131 _RF_S|_RF_A| _RF_U| _RF_SZ(16) | _RF_RS(0), /* UA16 */
134 _RF_S|_RF_A| _RF_SZ(32) | _RF_RS(10), /* GD_HI22 */
135 _RF_S|_RF_A| _RF_SZ(32) | _RF_RS(0), /* GD_LO10 */
137 _RF_A|_RF_P| _RF_SZ(32) | _RF_RS(2), /* GD_CALL */
138 _RF_S|_RF_A| _RF_SZ(32) | _RF_RS(10), /* LDM_HI22 */
139 _RF_S|_RF_A| _RF_SZ(32) | _RF_RS(0), /* LDM_LO10 */
141 _RF_A|_RF_P| _RF_SZ(32) | _RF_RS(2), /* LDM_CALL */
142 _RF_S|_RF_A| _RF_SZ(32) | _RF_RS(10), /* LDO_HIX22 */
143 _RF_S|_RF_A| _RF_SZ(32) | _RF_RS(0), /* LDO_LOX10 */
145 _RF_S|_RF_A| _RF_SZ(32) | _RF_RS(10), /* IE_HI22 */
146 _RF_S|_RF_A| _RF_SZ(32) | _RF_RS(0), /* IE_LO10 */
150 _RF_S|_RF_A| _RF_O| _RF_SZ(32) | _RF_RS(10), /* LE_HIX22 */
151 _RF_S|_RF_A| _RF_O| _RF_SZ(32) | _RF_RS(0), /* LE_LOX10 */
152 _RF_S| _RF_I| _RF_SZ(32) | _RF_RS(0), /* DTPMOD32 */
153 _RF_S| _RF_I| _RF_SZ(64) | _RF_RS(0), /* DTPMOD64 */
154 _RF_S|_RF_A| _RF_D| _RF_SZ(32) | _RF_RS(0), /* DTPOFF32 */
155 _RF_S|_RF_A| _RF_D| _RF_SZ(64) | _RF_RS(0), /* DTPOFF64 */
156 _RF_S|_RF_A| _RF_O| _RF_SZ(32) | _RF_RS(0), /* TPOFF32 */
157 _RF_S|_RF_A| _RF_O| _RF_SZ(64) | _RF_RS(0) /* TPOFF64 */
161 static const char *const reloc_names[] = {
162 "NONE", "8", "16", "32", "DISP_8", "DISP_16", "DISP_32", "WDISP_30",
163 "WDISP_22", "HI22", "22", "13", "LO10", "GOT10", "GOT13", "GOT22",
164 "PC10", "PC22", "WPLT30", "COPY", "GLOB_DAT", "JMP_SLOT", "RELATIVE",
165 "UA_32", "PLT32", "HIPLT22", "LOPLT10", "LOPLT10", "PCPLT22",
166 "PCPLT32", "10", "11", "64", "OLO10", "HH22", "HM10", "LM22",
167 "PC_HH22", "PC_HM10", "PC_LM22", "WDISP16", "WDISP19", "GLOB_JMP",
168 "7", "5", "6", "DISP64", "PLT64", "HIX22", "LOX10", "H44", "M44",
169 "L44", "REGISTER", "UA64", "UA16", "GD_HI22", "GD_LO10", "GD_ADD",
170 "GD_CALL", "LDM_HI22", "LDMO10", "LDM_ADD", "LDM_CALL", "LDO_HIX22",
171 "LDO_LOX10", "LDO_ADD", "IE_HI22", "IE_LO10", "IE_LD", "IE_LDX",
172 "IE_ADD", "LE_HIX22", "LE_LOX10", "DTPMOD32", "DTPMOD64", "DTPOFF32",
173 "DTPOFF64", "TPOFF32", "TPOFF64"
177 #define RELOC_RESOLVE_SYMBOL(t) ((reloc_target_flags[t] & _RF_S) != 0)
178 #define RELOC_PC_RELATIVE(t) ((reloc_target_flags[t] & _RF_P) != 0)
179 #define RELOC_BASE_RELATIVE(t) ((reloc_target_flags[t] & _RF_B) != 0)
180 #define RELOC_UNALIGNED(t) ((reloc_target_flags[t] & _RF_U) != 0)
181 #define RELOC_USE_ADDEND(t) ((reloc_target_flags[t] & _RF_A) != 0)
182 #define RELOC_BARE_SYMBOL(t) ((reloc_target_flags[t] & _RF_X) != 0)
183 #define RELOC_USE_TLS_DOFF(t) ((reloc_target_flags[t] & _RF_D) != 0)
184 #define RELOC_USE_TLS_OFF(t) ((reloc_target_flags[t] & _RF_O) != 0)
185 #define RELOC_USE_TLS_ID(t) ((reloc_target_flags[t] & _RF_I) != 0)
186 #define RELOC_TARGET_SIZE(t) ((reloc_target_flags[t] >> 8) & 0xff)
187 #define RELOC_VALUE_RIGHTSHIFT(t) (reloc_target_flags[t] & 0xff)
189 static const long reloc_target_bitmask[] = {
190 #define _BM(x) (~(-(1ULL << (x))))
192 _BM(8), _BM(16), _BM(32), /* 8, 16, 32 */
193 _BM(8), _BM(16), _BM(32), /* DISP8, DISP16, DISP32 */
194 _BM(30), _BM(22), /* WDISP30, WDISP22 */
195 _BM(22), _BM(22), /* HI22, 22 */
196 _BM(13), _BM(10), /* 13, LO10 */
197 _BM(10), _BM(13), _BM(22), /* GOT10, GOT13, GOT22 */
198 _BM(10), _BM(22), /* PC10, PC22 */
199 _BM(30), 0, /* WPLT30, COPY */
200 _BM(32), _BM(32), _BM(32), /* GLOB_DAT, JMP_SLOT, RELATIVE */
201 _BM(32), _BM(32), /* UA32, PLT32 */
202 _BM(22), _BM(10), /* HIPLT22, LOPLT10 */
203 _BM(32), _BM(22), _BM(10), /* PCPLT32, PCPLT22, PCPLT10 */
204 _BM(10), _BM(11), -1, /* 10, 11, 64 */
205 _BM(13), _BM(22), /* OLO10, HH22 */
206 _BM(10), _BM(22), /* HM10, LM22 */
207 _BM(22), _BM(10), _BM(22), /* PC_HH22, PC_HM10, PC_LM22 */
208 _BM(16), _BM(19), /* WDISP16, WDISP19 */
210 _BM(7), _BM(5), _BM(6), /* 7, 5, 6 */
211 -1, -1, /* DISP64, PLT64 */
212 _BM(22), _BM(13), /* HIX22, LOX10 */
213 _BM(22), _BM(10), _BM(13), /* H44, M44, L44 */
214 -1, -1, _BM(16), /* REGISTER, UA64, UA16 */
215 _BM(22), _BM(10), 0, _BM(30), /* GD_HI22, GD_LO10, GD_ADD, GD_CALL */
216 _BM(22), _BM(10), 0, /* LDM_HI22, LDMO10, LDM_ADD */
217 _BM(30), /* LDM_CALL */
218 _BM(22), _BM(10), 0, /* LDO_HIX22, LDO_LOX10, LDO_ADD */
219 _BM(22), _BM(10), 0, 0, /* IE_HI22, IE_LO10, IE_LD, IE_LDX */
221 _BM(22), _BM(13), /* LE_HIX22, LE_LOX10 */
222 _BM(32), -1, /* DTPMOD32, DTPMOD64 */
223 _BM(32), -1, /* DTPOFF32, DTPOFF64 */
224 _BM(32), -1 /* TPOFF32, TPOFF64 */
227 #define RELOC_VALUE_BITMASK(t) (reloc_target_bitmask[t])
230 #define flush(va, offs) \
231 __asm __volatile("flush %0 + %1" : : "r" (va), "I" (offs));
233 static int reloc_nonplt_object(Obj_Entry *obj, const Elf_Rela *rela,
235 static void install_plt(Elf_Word *pltgot, Elf_Addr proc);
237 extern char _rtld_bind_start_0[];
238 extern char _rtld_bind_start_1[];
241 do_copy_relocations(Obj_Entry *dstobj)
243 const Elf_Rela *relalim;
244 const Elf_Rela *rela;
245 const Elf_Sym *dstsym;
246 const Elf_Sym *srcsym;
255 assert(dstobj->mainprog); /* COPY relocations are invalid elsewhere */
257 relalim = (const Elf_Rela *)((caddr_t)dstobj->rela + dstobj->relasize);
258 for (rela = dstobj->rela; rela < relalim; rela++) {
259 if (ELF_R_TYPE(rela->r_info) == R_SPARC_COPY) {
260 dstaddr = (void *)(dstobj->relocbase + rela->r_offset);
261 dstsym = dstobj->symtab + ELF_R_SYM(rela->r_info);
262 name = dstobj->strtab + dstsym->st_name;
263 hash = elf_hash(name);
264 size = dstsym->st_size;
265 ve = fetch_ventry(dstobj, ELF_R_SYM(rela->r_info));
267 for (srcobj = dstobj->next; srcobj != NULL;
268 srcobj = srcobj->next)
269 if ((srcsym = symlook_obj(name, hash, srcobj,
273 if (srcobj == NULL) {
274 _rtld_error("Undefined symbol \"%s\""
275 "referenced from COPY relocation"
276 "in %s", name, dstobj->path);
280 srcaddr = (const void *)(srcobj->relocbase +
282 memcpy(dstaddr, srcaddr, size);
290 reloc_non_plt(Obj_Entry *obj, Obj_Entry *obj_rtld)
292 const Elf_Rela *relalim;
293 const Elf_Rela *rela;
295 int bytes = obj->nchains * sizeof(SymCache);
299 * The dynamic loader may be called from a thread, we have
300 * limited amounts of stack available so we cannot use alloca().
302 if (obj != obj_rtld) {
303 cache = mmap(NULL, bytes, PROT_READ|PROT_WRITE, MAP_ANON,
305 if (cache == MAP_FAILED)
310 relalim = (const Elf_Rela *)((caddr_t)obj->rela + obj->relasize);
311 for (rela = obj->rela; rela < relalim; rela++) {
312 if (reloc_nonplt_object(obj, rela, cache) < 0)
318 munmap(cache, bytes);
323 reloc_nonplt_object(Obj_Entry *obj, const Elf_Rela *rela, SymCache *cache)
325 const Obj_Entry *defobj;
333 where = (Elf_Addr *)(obj->relocbase + rela->r_offset);
334 where32 = (Elf_Word *)where;
338 type = ELF64_R_TYPE_ID(rela->r_info);
339 if (type == R_SPARC_NONE)
342 /* We do JMP_SLOTs below. */
343 if (type == R_SPARC_JMP_SLOT)
346 /* COPY relocs are also handled elsewhere. */
347 if (type == R_SPARC_COPY)
350 /* Ignore ADD and CALL relocations for dynamic TLS references. */
351 if (type == R_SPARC_TLS_GD_ADD || type == R_SPARC_TLS_GD_CALL ||
352 type == R_SPARC_TLS_LDM_ADD || type == R_SPARC_TLS_LDM_CALL ||
353 type == R_SPARC_TLS_LDO_ADD)
357 * Note: R_SPARC_TLS_TPOFF64 must be the numerically largest
360 if (type >= sizeof(reloc_target_bitmask) /
361 sizeof(*reloc_target_bitmask)) {
362 _rtld_error("%s: Unsupported relocation type %d in non-PLT "
363 "object\n", obj->path, type);
367 value = rela->r_addend;
370 * Handle relative relocs here, because we might not be able to access
373 if (type == R_SPARC_RELATIVE) {
374 /* XXXX -- apparently we ignore the preexisting value. */
375 *where = (Elf_Addr)(obj->relocbase + value);
380 * If we get here while relocating rtld itself, we will crash because
381 * a non-local variable is accessed.
383 if (RELOC_RESOLVE_SYMBOL(type)) {
384 /* Find the symbol. */
385 def = find_symdef(ELF_R_SYM(rela->r_info), obj, &defobj,
390 if (RELOC_USE_TLS_ID(type))
391 value = (Elf_Addr)defobj->tlsindex;
392 else if (RELOC_USE_TLS_DOFF(type))
393 value += (Elf_Addr)def->st_value;
394 else if (RELOC_USE_TLS_OFF(type)) {
396 * We lazily allocate offsets for static TLS as we
397 * see the first relocation that references the TLS
398 * block. This allows us to support (small amounts
399 * of) static TLS in dynamically loaded modules. If
400 * we run out of space, we generate an error.
402 if (!defobj->tls_done &&
403 !allocate_tls_offset((Obj_Entry*)defobj)) {
404 _rtld_error("%s: No space available for "
405 "static Thread Local Storage", obj->path);
408 value += (Elf_Addr)(def->st_value -
411 /* Add in the symbol's absolute address. */
412 value += (Elf_Addr)(def->st_value +
417 if (type == R_SPARC_OLO10)
418 value = (value & 0x3ff) + ELF64_R_TYPE_DATA(rela->r_info);
420 if (type == R_SPARC_HIX22 || type == R_SPARC_TLS_LE_HIX22)
421 value ^= 0xffffffffffffffff;
423 if (RELOC_PC_RELATIVE(type))
424 value -= (Elf_Addr)where;
426 if (RELOC_BASE_RELATIVE(type)) {
428 * Note that even though sparcs use `Elf_rela' exclusively
429 * we still need the implicit memory addend in relocations
430 * referring to GOT entries. Undoubtedly, someone f*cked
431 * this up in the distant past, and now we're stuck with
432 * it in the name of compatibility for all eternity ...
434 * In any case, the implicit and explicit should be mutually
435 * exclusive. We provide a check for that here.
437 /* XXXX -- apparently we ignore the preexisting value */
438 value += (Elf_Addr)(obj->relocbase);
441 mask = RELOC_VALUE_BITMASK(type);
442 value >>= RELOC_VALUE_RIGHTSHIFT(type);
445 if (type == R_SPARC_LOX10 || type == R_SPARC_TLS_LE_LOX10)
448 if (RELOC_UNALIGNED(type)) {
449 /* Handle unaligned relocations. */
455 size = RELOC_TARGET_SIZE(type) / 8;
459 /* Read it in one byte at a time. */
460 for (i = 0; i < size; i++)
461 tmp = (tmp << 8) | ptr[i];
466 /* Write it back out. */
467 for (i = 0; i < size; i++)
468 ptr[i] = ((tmp >> ((size - i - 1) * 8)) & 0xff);
469 } else if (RELOC_TARGET_SIZE(type) > 32) {
481 reloc_plt(Obj_Entry *obj)
484 const Obj_Entry *defobj;
485 const Elf_Rela *relalim;
486 const Elf_Rela *rela;
491 relalim = (const Elf_Rela *)((char *)obj->pltrela + obj->pltrelasize);
492 for (rela = obj->pltrela; rela < relalim; rela++) {
493 if (rela->r_addend == 0)
495 assert(ELF64_R_TYPE_ID(rela->r_info) == R_SPARC_JMP_SLOT);
496 where = (Elf_Addr *)(obj->relocbase + rela->r_offset);
497 def = find_symdef(ELF_R_SYM(rela->r_info), obj, &defobj,
499 value = (Elf_Addr)(defobj->relocbase + def->st_value);
507 * Instruction templates:
509 #define BAA 0x10400000 /* ba,a %xcc, 0 */
510 #define SETHI 0x03000000 /* sethi %hi(0), %g1 */
511 #define JMP 0x81c06000 /* jmpl %g1+%lo(0), %g0 */
512 #define NOP 0x01000000 /* sethi %hi(0), %g0 */
513 #define OR 0x82806000 /* or %g1, 0, %g1 */
514 #define XOR 0x82c06000 /* xor %g1, 0, %g1 */
515 #define MOV71 0x8283a000 /* or %o7, 0, %g1 */
516 #define MOV17 0x9c806000 /* or %g1, 0, %o7 */
517 #define CALL 0x40000000 /* call 0 */
518 #define SLLX 0x8b407000 /* sllx %g1, 0, %g1 */
519 #define SETHIG5 0x0b000000 /* sethi %hi(0), %g5 */
520 #define ORG5 0x82804005 /* or %g1, %g5, %g1 */
522 /* %hi(v) with variable shift */
523 #define HIVAL(v, s) (((v) >> (s)) & 0x003fffff)
524 #define LOVAL(v) ((v) & 0x000003ff)
527 reloc_jmpslots(Obj_Entry *obj)
529 const Obj_Entry *defobj;
530 const Elf_Rela *relalim;
531 const Elf_Rela *rela;
536 relalim = (const Elf_Rela *)((char *)obj->pltrela + obj->pltrelasize);
537 for (rela = obj->pltrela; rela < relalim; rela++) {
538 assert(ELF64_R_TYPE_ID(rela->r_info) == R_SPARC_JMP_SLOT);
539 where = (Elf_Addr *)(obj->relocbase + rela->r_offset);
540 def = find_symdef(ELF_R_SYM(rela->r_info), obj, &defobj,
544 target = (Elf_Addr)(defobj->relocbase + def->st_value);
545 reloc_jmpslot(where, target, defobj, obj, (Elf_Rel *)rela);
547 obj->jmpslots_done = true;
552 reloc_jmpslot(Elf_Addr *wherep, Elf_Addr target, const Obj_Entry *obj,
553 const Obj_Entry *refobj, const Elf_Rel *rel)
555 const Elf_Rela *rela = (const Elf_Rela *)rel;
559 if (rela - refobj->pltrela < 32764) {
561 * At the PLT entry pointed at by `where', we now construct
562 * a direct transfer to the now fully resolved function
565 * A PLT entry is supposed to start by looking like this:
567 * sethi (. - .PLT0), %g1
576 * When we replace these entries we start from the second
577 * entry and do it in reverse order so the last thing we
578 * do is replace the branch. That allows us to change this
581 * We now need to find out how far we need to jump. We
582 * have a choice of several different relocation techniques
583 * which are increasingly expensive.
585 where = (Elf_Word *)wherep;
586 offset = ((Elf_Addr)where) - target;
587 if (offset <= (1L<<20) && offset >= -(1L<<20)) {
589 * We're within 1MB -- we can use a direct branch
592 * We can generate this pattern:
594 * sethi %hi(. - .PLT0), %g1
604 where[1] = BAA | ((offset >> 2) &0x3fffff);
606 } else if (target >= 0 && target < (1L<<32)) {
608 * We're withing 32-bits of address zero.
610 * The resulting code in the jump slot is:
612 * sethi %hi(. - .PLT0), %g1
613 * sethi %hi(addr), %g1
622 where[2] = JMP | LOVAL(target);
624 where[1] = SETHI | HIVAL(target, 10);
626 } else if (target <= 0 && target > -(1L<<32)) {
628 * We're withing 32-bits of address -1.
630 * The resulting code in the jump slot is:
632 * sethi %hi(. - .PLT0), %g1
633 * sethi %hix(addr), %g1
634 * xor %g1, %lox(addr), %g1
644 where[2] = XOR | ((~target) & 0x00001fff);
646 where[1] = SETHI | HIVAL(~target, 10);
648 } else if (offset <= (1L<<32) && offset >= -((1L<<32) - 4)) {
650 * We're withing 32-bits -- we can use a direct call
653 * The resulting code in the jump slot is:
655 * sethi %hi(. - .PLT0), %g1
667 where[2] = CALL | ((offset >> 4) & 0x3fffffff);
671 } else if (offset >= 0 && offset < (1L<<44)) {
673 * We're withing 44 bits. We can generate this
676 * The resulting code in the jump slot is:
678 * sethi %hi(. - .PLT0), %g1
679 * sethi %h44(addr), %g1
680 * or %g1, %m44(addr), %g1
688 where[4] = JMP | LOVAL(offset);
690 where[3] = SLLX | 12;
692 where[2] = OR | (((offset) >> 12) & 0x00001fff);
694 where[1] = SETHI | HIVAL(offset, 22);
696 } else if (offset < 0 && offset > -(1L<<44)) {
698 * We're withing 44 bits. We can generate this
701 * The resulting code in the jump slot is:
703 * sethi %hi(. - .PLT0), %g1
704 * sethi %h44(-addr), %g1
705 * xor %g1, %m44(-addr), %g1
713 where[4] = JMP | LOVAL(offset);
715 where[3] = SLLX | 12;
717 where[2] = XOR | (((~offset) >> 12) & 0x00001fff);
719 where[1] = SETHI | HIVAL(~offset, 22);
723 * We need to load all 64-bits
725 * The resulting code in the jump slot is:
727 * sethi %hi(. - .PLT0), %g1
728 * sethi %hh(addr), %g1
729 * sethi %lm(addr), %g5
730 * or %g1, %hm(addr), %g1
737 where[6] = JMP | LOVAL(target);
741 where[4] = SLLX | 32;
743 where[3] = OR | LOVAL((target) >> 32);
745 where[2] = SETHIG5 | HIVAL(target, 10);
747 where[1] = SETHI | HIVAL(target, 42);
752 * This is a high PLT slot; the relocation offset specifies a
753 * pointer that needs to be frobbed; no actual code needs to
754 * be modified. The pointer to be calculated needs the addend
755 * added and the reference object relocation base subtraced.
757 *wherep = target + rela->r_addend -
758 (Elf_Addr)refobj->relocbase;
765 * Install rtld function call into this PLT slot.
767 #define SAVE 0x9de3bf50
768 #define SETHI_l0 0x21000000
769 #define SETHI_l1 0x23000000
770 #define OR_l0_l0 0xa0142000
771 #define SLLX_l0_32_l0 0xa12c3020
772 #define OR_l0_l1_l0 0xa0140011
773 #define JMPL_l0_o1 0x93c42000
774 #define MOV_g1_o0 0x90100001
777 init_pltgot(Obj_Entry *obj)
781 if (obj->pltgot != NULL) {
782 entry = (Elf_Word *)obj->pltgot;
783 install_plt(&entry[0], (Elf_Addr)_rtld_bind_start_0);
784 install_plt(&entry[8], (Elf_Addr)_rtld_bind_start_1);
785 obj->pltgot[8] = (Elf_Addr)obj;
790 install_plt(Elf_Word *pltgot, Elf_Addr proc)
794 pltgot[1] = SETHI_l0 | HIVAL(proc, 42);
796 pltgot[2] = SETHI_l1 | HIVAL(proc, 10);
798 pltgot[3] = OR_l0_l0 | LOVAL((proc) >> 32);
800 pltgot[4] = SLLX_l0_32_l0;
802 pltgot[5] = OR_l0_l1_l0;
804 pltgot[6] = JMPL_l0_o1 | LOVAL(proc);
806 pltgot[7] = MOV_g1_o0;
811 allocate_initial_tls(Obj_Entry *objs)
816 * Fix the size of the static TLS block by using the maximum offset
817 * allocated so far and adding a bit for dynamic modules to use.
819 tls_static_space = tls_last_offset + RTLD_STATIC_TLS_EXTRA;
820 tpval = allocate_tls(objs, NULL, 3 * sizeof(Elf_Addr),
822 __asm __volatile("mov %0, %%g7" : : "r" (tpval));
825 void *__tls_get_addr(tls_index *ti)
827 register Elf_Addr** tp __asm__("%g7");
829 return (tls_get_addr_common(tp, ti->ti_module, ti->ti_offset));