elf_machdep.c revision 288287 
1/*-
2 * Copyright 1996-1998 John D. Polstra.
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
15 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
16 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
17 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
18 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
19 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
20 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
21 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
23 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 *
25 * $FreeBSD: stable/10/sys/ia64/ia64/elf_machdep.c 288287 2015-09-27 01:33:43Z kib $
26 */
27
28#include <sys/param.h>
29#include <sys/kernel.h>
30#include <sys/systm.h>
31#include <sys/exec.h>
32#include <sys/imgact.h>
33#include <sys/malloc.h>
34#include <sys/proc.h>
35#include <sys/namei.h>
36#include <sys/fcntl.h>
37#include <sys/vnode.h>
38#include <sys/linker.h>
39#include <sys/sysent.h>
40#include <sys/imgact_elf.h>
41#include <sys/syscall.h>
42#include <sys/signalvar.h>
43
44#include <vm/vm.h>
45#include <vm/vm_param.h>
46
47#include <machine/elf.h>
48#include <machine/frame.h>
49#include <machine/md_var.h>
50#include <machine/unwind.h>
51
52Elf_Addr link_elf_get_gp(linker_file_t);
53
54extern Elf_Addr fptr_storage[];
55
56struct sysentvec elf64_freebsd_sysvec = {
57	.sv_size	= SYS_MAXSYSCALL,
58	.sv_table	= sysent,
59	.sv_mask	= 0,
60	.sv_sigsize	= 0,
61	.sv_sigtbl	= NULL,
62	.sv_errsize	= 0,
63	.sv_errtbl	= NULL,
64	.sv_transtrap	= NULL,
65	.sv_fixup	= __elfN(freebsd_fixup),
66	.sv_sendsig	= sendsig,
67	.sv_sigcode	= NULL,
68	.sv_szsigcode	= NULL,
69	.sv_prepsyscall	= NULL,
70	.sv_name	= "FreeBSD ELF64",
71	.sv_coredump	= __elfN(coredump),
72	.sv_imgact_try	= NULL,
73	.sv_minsigstksz	= MINSIGSTKSZ,
74	.sv_pagesize	= PAGE_SIZE,
75	.sv_minuser	= VM_MIN_ADDRESS,
76	.sv_maxuser	= VM_MAXUSER_ADDRESS,
77	.sv_usrstack	= USRSTACK,
78	.sv_psstrings	= PS_STRINGS,
79	.sv_stackprot	= VM_PROT_READ|VM_PROT_WRITE,
80	.sv_copyout_strings = exec_copyout_strings,
81	.sv_setregs	= exec_setregs,
82	.sv_fixlimit	= NULL,
83	.sv_maxssiz	= NULL,
84	.sv_flags	= SV_ABI_FREEBSD | SV_LP64,
85	.sv_set_syscall_retval = cpu_set_syscall_retval,
86	.sv_fetch_syscall_args = cpu_fetch_syscall_args,
87	.sv_syscallnames = syscallnames,
88	.sv_schedtail	= NULL,
89};
90
91static Elf64_Brandinfo freebsd_brand_info = {
92	.brand		= ELFOSABI_FREEBSD,
93	.machine	= EM_IA_64,
94	.compat_3_brand	= "FreeBSD",
95	.emul_path	= NULL,
96	.interp_path	= "/libexec/ld-elf.so.1",
97	.sysvec		= &elf64_freebsd_sysvec,
98	.interp_newpath	= NULL,
99	.brand_note	= &elf64_freebsd_brandnote,
100	.flags		= BI_CAN_EXEC_DYN | BI_BRAND_NOTE
101};
102SYSINIT(elf64, SI_SUB_EXEC, SI_ORDER_FIRST,
103    (sysinit_cfunc_t)elf64_insert_brand_entry, &freebsd_brand_info);
104
105static Elf64_Brandinfo freebsd_brand_oinfo = {
106	.brand		= ELFOSABI_FREEBSD,
107	.machine	= EM_IA_64,
108	.compat_3_brand	= "FreeBSD",
109	.emul_path	= NULL,
110	.interp_path	= "/usr/libexec/ld-elf.so.1",
111	.sysvec		= &elf64_freebsd_sysvec,
112	.interp_newpath	= NULL,
113	.brand_note	= &elf64_freebsd_brandnote,
114	.flags		= BI_CAN_EXEC_DYN | BI_BRAND_NOTE
115};
116SYSINIT(oelf64, SI_SUB_EXEC, SI_ORDER_ANY,
117    (sysinit_cfunc_t)elf64_insert_brand_entry, &freebsd_brand_oinfo);
118
119
120void
121elf64_dump_thread(struct thread *td, void *dst, size_t *off __unused)
122{
123
124	/* Flush the dirty registers onto the backingstore. */
125	if (dst == NULL)
126		ia64_flush_dirty(td, &td->td_frame->tf_special);
127}
128
129
130static int
131lookup_fdesc(linker_file_t lf, Elf_Size symidx, elf_lookup_fn lookup,
132    Elf_Addr *addr1)
133{
134	linker_file_t top;
135	Elf_Addr addr;
136	const char *symname;
137	int i, error;
138	static int eot = 0;
139
140	error = lookup(lf, symidx, 0, &addr);
141	if (error != 0) {
142		top = lf;
143		symname = elf_get_symname(top, symidx);
144		for (i = 0; i < top->ndeps; i++) {
145			lf = top->deps[i];
146			addr = (Elf_Addr)linker_file_lookup_symbol(lf,
147			    symname, 0);
148			if (addr != 0)
149				break;
150		}
151		if (addr == 0)
152			return (EINVAL);
153	}
154
155	if (eot)
156		return (EINVAL);
157
158	/*
159	 * Lookup and/or construct OPD
160	 */
161	for (i = 0; i < 8192; i += 2) {
162		if (fptr_storage[i] == addr) {
163			*addr1 = (Elf_Addr)(fptr_storage + i);
164			return (0);
165		}
166
167		if (fptr_storage[i] == 0) {
168			fptr_storage[i] = addr;
169			fptr_storage[i+1] = link_elf_get_gp(lf);
170			*addr1 = (Elf_Addr)(fptr_storage + i);
171			return (0);
172		}
173	}
174
175	printf("%s: fptr table full\n", __func__);
176	eot = 1;
177
178	return (EINVAL);
179}
180
181/* Process one elf relocation with addend. */
182static int
183elf_reloc_internal(linker_file_t lf, Elf_Addr relocbase, const void *data,
184    int type, int local, elf_lookup_fn lookup)
185{
186	Elf_Addr *where;
187	Elf_Addr addend, addr;
188	Elf_Size rtype, symidx;
189	const Elf_Rel *rel;
190	const Elf_Rela *rela;
191	int error;
192
193	switch (type) {
194	case ELF_RELOC_REL:
195		rel = (const Elf_Rel *)data;
196		where = (Elf_Addr *)(relocbase + rel->r_offset);
197		rtype = ELF_R_TYPE(rel->r_info);
198		symidx = ELF_R_SYM(rel->r_info);
199		switch (rtype) {
200		case R_IA_64_DIR64LSB:
201		case R_IA_64_FPTR64LSB:
202		case R_IA_64_REL64LSB:
203			addend = *where;
204			break;
205		default:
206			addend = 0;
207			break;
208		}
209		break;
210	case ELF_RELOC_RELA:
211		rela = (const Elf_Rela *)data;
212		where = (Elf_Addr *)(relocbase + rela->r_offset);
213		rtype = ELF_R_TYPE(rela->r_info);
214		symidx = ELF_R_SYM(rela->r_info);
215		addend = rela->r_addend;
216		break;
217	default:
218		panic("%s: invalid ELF relocation (0x%x)\n", __func__, type);
219	}
220
221	if (local) {
222		if (rtype == R_IA_64_REL64LSB)
223			*where = elf_relocaddr(lf, relocbase + addend);
224		return (0);
225	}
226
227	switch (rtype) {
228	case R_IA_64_NONE:
229		break;
230	case R_IA_64_DIR64LSB:	/* word64 LSB	S + A */
231		error = lookup(lf, symidx, 1, &addr);
232		if (error != 0)
233			return (-1);
234		*where = addr + addend;
235		break;
236	case R_IA_64_FPTR64LSB:	/* word64 LSB	@fptr(S + A) */
237		if (addend != 0) {
238			printf("%s: addend ignored for OPD relocation\n",
239			    __func__);
240		}
241		error = lookup_fdesc(lf, symidx, lookup, &addr);
242		if (error != 0)
243			return (-1);
244		*where = addr;
245		break;
246	case R_IA_64_REL64LSB:	/* word64 LSB	BD + A */
247		break;
248	case R_IA_64_IPLTLSB:
249		error = lookup_fdesc(lf, symidx, lookup, &addr);
250		if (error != 0)
251			return (-1);
252		where[0] = *((Elf_Addr*)addr) + addend;
253		where[1] = *((Elf_Addr*)addr + 1);
254		break;
255	default:
256		printf("%s: unknown relocation (0x%x)\n", __func__,
257		    (int)rtype);
258		return -1;
259	}
260
261	return (0);
262}
263
264int
265elf_reloc(linker_file_t lf, Elf_Addr relocbase, const void *data, int type,
266    elf_lookup_fn lookup)
267{
268
269	return (elf_reloc_internal(lf, relocbase, data, type, 0, lookup));
270}
271
272int
273elf_reloc_local(linker_file_t lf, Elf_Addr relocbase, const void *data,
274    int type, elf_lookup_fn lookup)
275{
276
277	return (elf_reloc_internal(lf, relocbase, data, type, 1, lookup));
278}
279
280int
281elf_cpu_load_file(linker_file_t lf)
282{
283	Elf_Ehdr *hdr;
284	Elf_Phdr *ph, *phlim;
285	Elf_Addr reloc, vaddr;
286
287	hdr = (Elf_Ehdr *)(lf->address);
288	if (!IS_ELF(*hdr)) {
289		printf("Missing or corrupted ELF header at %p\n", hdr);
290		return (EFTYPE);
291	}
292
293	/*
294	 * Iterate over the segments and register the unwind table if
295	 * we come across it.
296	 */
297	ph = (Elf_Phdr *)(lf->address + hdr->e_phoff);
298	phlim = ph + hdr->e_phnum;
299	reloc = ~0ULL;
300	while (ph < phlim) {
301		if (ph->p_type == PT_LOAD && reloc == ~0ULL)
302			reloc = (Elf_Addr)lf->address - ph->p_vaddr;
303
304		if (ph->p_type == PT_IA_64_UNWIND) {
305			vaddr = ph->p_vaddr + reloc;
306			unw_table_add((vm_offset_t)lf->address, vaddr,
307			    vaddr + ph->p_memsz);
308		}
309		++ph;
310	}
311
312	/*
313	 * Make the I-cache coherent, but don't worry obout the kernel
314	 * itself because the loader needs to do that.
315	 */
316	if (lf->id != 1)
317		ia64_sync_icache((uintptr_t)lf->address, lf->size);
318
319	return (0);
320}
321
322int
323elf_cpu_unload_file(linker_file_t lf)
324{
325
326	unw_table_remove((vm_offset_t)lf->address);
327	return (0);
328}
329