2 * Copyright 1996-1998 John D. Polstra.
3 * Copyright (c) 2015 Ruslan Bukin <br@bsdpad.com>
4 * Copyright (c) 2016 Yukishige Shibata <y-shibat@mtd.biglobe.ne.jp>
7 * Portions of this software were developed by SRI International and the
8 * University of Cambridge Computer Laboratory under DARPA/AFRL contract
9 * FA8750-10-C-0237 ("CTSRD"), as part of the DARPA CRASH research programme.
11 * Portions of this software were developed by the University of Cambridge
12 * Computer Laboratory as part of the CTSRD Project, with support from the
13 * UK Higher Education Innovation Fund (HEIF).
15 * Redistribution and use in source and binary forms, with or without
16 * modification, are permitted provided that the following conditions
18 * 1. Redistributions of source code must retain the above copyright
19 * notice, this list of conditions and the following disclaimer.
20 * 2. Redistributions in binary form must reproduce the above copyright
21 * notice, this list of conditions and the following disclaimer in the
22 * documentation and/or other materials provided with the distribution.
24 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
37 #include <sys/cdefs.h>
38 __FBSDID("$FreeBSD$");
40 #include <sys/param.h>
41 #include <sys/kernel.h>
42 #include <sys/systm.h>
44 #include <sys/imgact.h>
45 #include <sys/linker.h>
47 #include <sys/sysctl.h>
48 #include <sys/sysent.h>
49 #include <sys/imgact_elf.h>
50 #include <sys/syscall.h>
51 #include <sys/signalvar.h>
52 #include <sys/vnode.h>
56 #include <vm/vm_param.h>
58 #include <machine/elf.h>
59 #include <machine/md_var.h>
61 static const char *riscv_machine_arch(struct proc *p);
65 struct sysentvec elf64_freebsd_sysvec = {
66 .sv_size = SYS_MAXSYSCALL,
69 .sv_fixup = __elfN(freebsd_fixup),
70 .sv_sendsig = sendsig,
71 .sv_sigcode = sigcode,
72 .sv_szsigcode = &szsigcode,
73 .sv_name = "FreeBSD ELF64",
74 .sv_coredump = __elfN(coredump),
75 .sv_imgact_try = NULL,
76 .sv_minsigstksz = MINSIGSTKSZ,
77 .sv_minuser = VM_MIN_ADDRESS,
78 .sv_maxuser = VM_MAXUSER_ADDRESS,
79 .sv_usrstack = USRSTACK,
80 .sv_psstrings = PS_STRINGS,
81 .sv_stackprot = VM_PROT_READ | VM_PROT_WRITE,
82 .sv_copyout_auxargs = __elfN(freebsd_copyout_auxargs),
83 .sv_copyout_strings = exec_copyout_strings,
84 .sv_setregs = exec_setregs,
87 .sv_flags = SV_ABI_FREEBSD | SV_LP64 | SV_SHP | SV_ASLR |
89 .sv_set_syscall_retval = cpu_set_syscall_retval,
90 .sv_fetch_syscall_args = cpu_fetch_syscall_args,
91 .sv_syscallnames = syscallnames,
92 .sv_shared_page_base = SHAREDPAGE,
93 .sv_shared_page_len = PAGE_SIZE,
95 .sv_thread_detach = NULL,
97 .sv_hwcap = &elf_hwcap,
98 .sv_machine_arch = riscv_machine_arch,
100 INIT_SYSENTVEC(elf64_sysvec, &elf64_freebsd_sysvec);
103 riscv_machine_arch(struct proc *p)
106 if ((p->p_elf_flags & EF_RISCV_FLOAT_ABI_MASK) ==
107 EF_RISCV_FLOAT_ABI_SOFT)
108 return (MACHINE_ARCH "sf");
109 return (MACHINE_ARCH);
112 static Elf64_Brandinfo freebsd_brand_info = {
113 .brand = ELFOSABI_FREEBSD,
115 .compat_3_brand = "FreeBSD",
117 .interp_path = "/libexec/ld-elf.so.1",
118 .sysvec = &elf64_freebsd_sysvec,
119 .interp_newpath = NULL,
120 .brand_note = &elf64_freebsd_brandnote,
121 .flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE
124 SYSINIT(elf64, SI_SUB_EXEC, SI_ORDER_FIRST,
125 (sysinit_cfunc_t)elf64_insert_brand_entry, &freebsd_brand_info);
127 static bool debug_kld;
128 SYSCTL_BOOL(_debug, OID_AUTO, kld_reloc, CTLFLAG_RW, &debug_kld, 0,
129 "Activate debug prints in elf_reloc_internal()");
131 struct type2str_ent {
137 elf64_dump_thread(struct thread *td, void *dst, size_t *off)
143 * Following 4 functions are used to manupilate bits on 32bit interger value.
144 * FIXME: I implemetend for ease-to-understand rather than for well-optimized.
147 gen_bitmask(int msb, int lsb)
151 if (msb == sizeof(mask) * 8 - 1)
154 mask = (1U << (msb + 1)) - 1;
157 mask &= ~((1U << lsb) - 1);
163 extract_bits(uint32_t x, int msb, int lsb)
167 mask = gen_bitmask(msb, lsb);
176 insert_bits(uint32_t d, uint32_t s, int msb, int lsb)
180 mask = gen_bitmask(msb, lsb);
191 insert_imm(uint32_t insn, uint32_t imm, int imm_msb, int imm_lsb,
197 v = extract_bits(imm, imm_msb, imm_lsb);
198 insn_msb = (imm_msb - imm_lsb) + insn_lsb;
200 return (insert_bits(insn, v, insn_msb, insn_lsb));
204 * The RISC-V ISA is designed so that all of immediate values are
206 * An immediate value is sometimes generated at runtime by adding
207 * 12bit sign integer and 20bit signed integer. This requests 20bit
208 * immediate value to be ajusted if the MSB of the 12bit immediate
209 * value is asserted (sign-extended value is treated as negative value).
211 * For example, 0x123800 can be calculated by adding upper 20 bit of
212 * 0x124000 and sign-extended 12bit immediate whose bit pattern is
216 * = (0x123000 + 0x1000) + (-0x1000 + 0x800)
217 * = (0x123000 + 0x1000) + (0xff...ff800)
218 * = 0x124000 + sign-extention(0x800)
221 calc_hi20_imm(uint32_t value)
224 * There is the arithmetical hack that can remove conditional
225 * statement. But I implement it in straightforward way.
227 if ((value & 0x800) != 0)
229 return (value & ~0xfff);
232 static const struct type2str_ent t2s[] = {
233 { R_RISCV_NONE, "R_RISCV_NONE" },
234 { R_RISCV_64, "R_RISCV_64" },
235 { R_RISCV_JUMP_SLOT, "R_RISCV_JUMP_SLOT" },
236 { R_RISCV_RELATIVE, "R_RISCV_RELATIVE" },
237 { R_RISCV_JAL, "R_RISCV_JAL" },
238 { R_RISCV_CALL, "R_RISCV_CALL" },
239 { R_RISCV_PCREL_HI20, "R_RISCV_PCREL_HI20" },
240 { R_RISCV_PCREL_LO12_I, "R_RISCV_PCREL_LO12_I" },
241 { R_RISCV_PCREL_LO12_S, "R_RISCV_PCREL_LO12_S" },
242 { R_RISCV_HI20, "R_RISCV_HI20" },
243 { R_RISCV_LO12_I, "R_RISCV_LO12_I" },
244 { R_RISCV_LO12_S, "R_RISCV_LO12_S" },
248 reloctype_to_str(int type)
252 for (i = 0; i < sizeof(t2s) / sizeof(t2s[0]); ++i) {
253 if (type == t2s[i].type)
261 elf_is_ifunc_reloc(Elf_Size r_info __unused)
268 * Currently kernel loadable module for RISCV is compiled with -fPIC option.
269 * (see also additional CFLAGS definition for RISCV in sys/conf/kmod.mk)
270 * Only R_RISCV_64, R_RISCV_JUMP_SLOT and RISCV_RELATIVE are emitted in
271 * the module. Other relocations will be processed when kernel loadable
272 * modules are built in non-PIC.
274 * FIXME: only RISCV64 is supported.
277 elf_reloc_internal(linker_file_t lf, Elf_Addr relocbase, const void *data,
278 int type, int local, elf_lookup_fn lookup)
280 Elf_Size rtype, symidx;
281 const Elf_Rela *rela;
294 rela = (const Elf_Rela *)data;
295 where = (Elf_Addr *)(relocbase + rela->r_offset);
296 insn32p = (uint32_t *)where;
297 addend = rela->r_addend;
298 rtype = ELF_R_TYPE(rela->r_info);
299 symidx = ELF_R_SYM(rela->r_info);
302 printf("%s:%d unknown reloc type %d\n",
303 __FUNCTION__, __LINE__, type);
312 case R_RISCV_JUMP_SLOT:
313 error = lookup(lf, symidx, 1, &addr);
322 printf("%p %c %-24s %016lx -> %016lx\n", where,
323 (local ? 'l' : 'g'), reloctype_to_str(rtype),
327 case R_RISCV_RELATIVE:
329 *where = elf_relocaddr(lf, relocbase + addend);
331 printf("%p %c %-24s %016lx -> %016lx\n", where,
332 (local ? 'l' : 'g'), reloctype_to_str(rtype),
337 error = lookup(lf, symidx, 1, &addr);
341 val = addr - (Elf_Addr)where;
342 if (val <= -(1UL << 20) || (1UL << 20) <= val) {
343 printf("kldload: huge offset against R_RISCV_JAL\n");
348 *insn32p = insert_imm(*insn32p, val, 20, 20, 31);
349 *insn32p = insert_imm(*insn32p, val, 10, 1, 21);
350 *insn32p = insert_imm(*insn32p, val, 11, 11, 20);
351 *insn32p = insert_imm(*insn32p, val, 19, 12, 12);
353 printf("%p %c %-24s %08x -> %08x\n", where,
354 (local ? 'l' : 'g'), reloctype_to_str(rtype),
360 * R_RISCV_CALL relocates 8-byte region that consists
361 * of the sequence of AUIPC and JALR.
363 /* Calculate and check the pc relative offset. */
364 error = lookup(lf, symidx, 1, &addr);
368 val = addr - (Elf_Addr)where;
369 if (val <= -(1UL << 32) || (1UL << 32) <= val) {
370 printf("kldload: huge offset against R_RISCV_CALL\n");
374 /* Relocate AUIPC. */
375 before32 = insn32p[0];
376 imm20 = calc_hi20_imm(val);
377 insn32p[0] = insert_imm(insn32p[0], imm20, 31, 12, 12);
380 before32_1 = insn32p[1];
381 insn32p[1] = insert_imm(insn32p[1], val, 11, 0, 20);
383 printf("%p %c %-24s %08x %08x -> %08x %08x\n", where,
384 (local ? 'l' : 'g'), reloctype_to_str(rtype),
385 before32, insn32p[0], before32_1, insn32p[1]);
388 case R_RISCV_PCREL_HI20:
389 error = lookup(lf, symidx, 1, &addr);
393 val = addr - (Elf_Addr)where;
394 insn32p = (uint32_t *)where;
396 imm20 = calc_hi20_imm(val);
397 *insn32p = insert_imm(*insn32p, imm20, 31, 12, 12);
399 printf("%p %c %-24s %08x -> %08x\n", where,
400 (local ? 'l' : 'g'), reloctype_to_str(rtype),
404 case R_RISCV_PCREL_LO12_I:
405 error = lookup(lf, symidx, 1, &addr);
409 val = addr - (Elf_Addr)where;
410 insn32p = (uint32_t *)where;
412 *insn32p = insert_imm(*insn32p, addr, 11, 0, 20);
414 printf("%p %c %-24s %08x -> %08x\n", where,
415 (local ? 'l' : 'g'), reloctype_to_str(rtype),
419 case R_RISCV_PCREL_LO12_S:
420 error = lookup(lf, symidx, 1, &addr);
424 val = addr - (Elf_Addr)where;
425 insn32p = (uint32_t *)where;
427 *insn32p = insert_imm(*insn32p, addr, 11, 5, 25);
428 *insn32p = insert_imm(*insn32p, addr, 4, 0, 7);
430 printf("%p %c %-24s %08x -> %08x\n", where,
431 (local ? 'l' : 'g'), reloctype_to_str(rtype),
436 error = lookup(lf, symidx, 1, &addr);
441 insn32p = (uint32_t *)where;
443 imm20 = calc_hi20_imm(val);
444 *insn32p = insert_imm(*insn32p, imm20, 31, 12, 12);
446 printf("%p %c %-24s %08x -> %08x\n", where,
447 (local ? 'l' : 'g'), reloctype_to_str(rtype),
452 error = lookup(lf, symidx, 1, &addr);
457 insn32p = (uint32_t *)where;
459 *insn32p = insert_imm(*insn32p, addr, 11, 0, 20);
461 printf("%p %c %-24s %08x -> %08x\n", where,
462 (local ? 'l' : 'g'), reloctype_to_str(rtype),
467 error = lookup(lf, symidx, 1, &addr);
472 insn32p = (uint32_t *)where;
474 *insn32p = insert_imm(*insn32p, addr, 11, 5, 25);
475 *insn32p = insert_imm(*insn32p, addr, 4, 0, 7);
477 printf("%p %c %-24s %08x -> %08x\n", where,
478 (local ? 'l' : 'g'), reloctype_to_str(rtype),
483 printf("kldload: unexpected relocation type %ld, "
484 "symbol index %ld\n", rtype, symidx);
492 elf_reloc(linker_file_t lf, Elf_Addr relocbase, const void *data, int type,
493 elf_lookup_fn lookup)
496 return (elf_reloc_internal(lf, relocbase, data, type, 0, lookup));
500 elf_reloc_local(linker_file_t lf, Elf_Addr relocbase, const void *data,
501 int type, elf_lookup_fn lookup)
504 return (elf_reloc_internal(lf, relocbase, data, type, 1, lookup));
508 elf_cpu_load_file(linker_file_t lf __unused)
515 elf_cpu_unload_file(linker_file_t lf __unused)
522 elf_cpu_parse_dynamic(caddr_t loadbase __unused, Elf_Dyn *dynamic __unused)