elf_machdep.c revision 294136 
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
26#include <sys/cdefs.h>
27__FBSDID("$FreeBSD: stable/10/sys/arm/arm/elf_machdep.c 294136 2016-01-16 07:56:49Z dchagin $");
28
29#include <sys/param.h>
30#include <sys/kernel.h>
31#include <sys/systm.h>
32#include <sys/exec.h>
33#include <sys/imgact.h>
34#include <sys/linker.h>
35#include <sys/sysent.h>
36#include <sys/imgact_elf.h>
37#include <sys/proc.h>
38#include <sys/syscall.h>
39#include <sys/signalvar.h>
40#include <sys/vnode.h>
41
42#include <vm/vm.h>
43#include <vm/pmap.h>
44#include <vm/vm_param.h>
45
46#include <machine/elf.h>
47#include <machine/md_var.h>
48
49struct sysentvec elf32_freebsd_sysvec = {
50	.sv_size	= SYS_MAXSYSCALL,
51	.sv_table	= sysent,
52	.sv_mask	= 0,
53	.sv_sigsize	= 0,
54	.sv_sigtbl	= NULL,
55	.sv_errsize	= 0,
56	.sv_errtbl	= NULL,
57	.sv_transtrap	= NULL,
58	.sv_fixup	= __elfN(freebsd_fixup),
59	.sv_sendsig	= sendsig,
60	.sv_sigcode	= sigcode,
61	.sv_szsigcode	= &szsigcode,
62	.sv_prepsyscall	= NULL,
63	.sv_name	= "FreeBSD ELF32",
64	.sv_coredump	= __elfN(coredump),
65	.sv_imgact_try	= NULL,
66	.sv_minsigstksz	= MINSIGSTKSZ,
67	.sv_pagesize	= PAGE_SIZE,
68	.sv_minuser	= VM_MIN_ADDRESS,
69	.sv_maxuser	= VM_MAXUSER_ADDRESS,
70	.sv_usrstack	= USRSTACK,
71	.sv_psstrings	= PS_STRINGS,
72	.sv_stackprot	= VM_PROT_ALL,
73	.sv_copyout_strings = exec_copyout_strings,
74	.sv_setregs	= exec_setregs,
75	.sv_fixlimit	= NULL,
76	.sv_maxssiz	= NULL,
77	.sv_flags	= SV_ABI_FREEBSD | SV_ILP32,
78	.sv_set_syscall_retval = cpu_set_syscall_retval,
79	.sv_fetch_syscall_args = cpu_fetch_syscall_args,
80	.sv_syscallnames = syscallnames,
81	.sv_schedtail	= NULL,
82	.sv_thread_detach = NULL,
83	.sv_trap	= NULL,
84};
85
86static Elf32_Brandinfo freebsd_brand_info = {
87	.brand		= ELFOSABI_FREEBSD,
88	.machine	= EM_ARM,
89	.compat_3_brand	= "FreeBSD",
90	.emul_path	= NULL,
91	.interp_path	= "/libexec/ld-elf.so.1",
92	.sysvec		= &elf32_freebsd_sysvec,
93	.interp_newpath	= NULL,
94	.brand_note	= &elf32_freebsd_brandnote,
95	.flags		= BI_CAN_EXEC_DYN | BI_BRAND_NOTE
96};
97
98SYSINIT(elf32, SI_SUB_EXEC, SI_ORDER_FIRST,
99	(sysinit_cfunc_t) elf32_insert_brand_entry,
100	&freebsd_brand_info);
101
102static Elf32_Brandinfo freebsd_brand_oinfo = {
103	.brand		= ELFOSABI_FREEBSD,
104	.machine	= EM_ARM,
105	.compat_3_brand	= "FreeBSD",
106	.emul_path	= NULL,
107	.interp_path	= "/usr/libexec/ld-elf.so.1",
108	.sysvec		= &elf32_freebsd_sysvec,
109	.interp_newpath	= NULL,
110	.brand_note	= &elf32_freebsd_brandnote,
111	.flags		= BI_CAN_EXEC_DYN | BI_BRAND_NOTE
112};
113
114SYSINIT(oelf32, SI_SUB_EXEC, SI_ORDER_ANY,
115	(sysinit_cfunc_t) elf32_insert_brand_entry,
116	&freebsd_brand_oinfo);
117
118
119void
120elf32_dump_thread(struct thread *td __unused, void *dst __unused,
121    size_t *off __unused)
122{
123}
124
125
126/* Process one elf relocation with addend. */
127static int
128elf_reloc_internal(linker_file_t lf, Elf_Addr relocbase, const void *data,
129    int type, int local, elf_lookup_fn lookup)
130{
131	Elf_Addr *where;
132	Elf_Addr addr;
133	Elf_Addr addend;
134	Elf_Word rtype, symidx;
135	const Elf_Rel *rel;
136	const Elf_Rela *rela;
137	int error;
138
139	switch (type) {
140	case ELF_RELOC_REL:
141		rel = (const Elf_Rel *)data;
142		where = (Elf_Addr *) (relocbase + rel->r_offset);
143		addend = *where;
144		rtype = ELF_R_TYPE(rel->r_info);
145		symidx = ELF_R_SYM(rel->r_info);
146		break;
147	case ELF_RELOC_RELA:
148		rela = (const Elf_Rela *)data;
149		where = (Elf_Addr *) (relocbase + rela->r_offset);
150		addend = rela->r_addend;
151		rtype = ELF_R_TYPE(rela->r_info);
152		symidx = ELF_R_SYM(rela->r_info);
153		break;
154	default:
155		panic("unknown reloc type %d\n", type);
156	}
157
158	if (local) {
159		if (rtype == R_ARM_RELATIVE) {	/* A + B */
160			addr = elf_relocaddr(lf, relocbase + addend);
161			if (*where != addr)
162				*where = addr;
163		}
164		return (0);
165	}
166
167	switch (rtype) {
168
169		case R_ARM_NONE:	/* none */
170			break;
171
172		case R_ARM_ABS32:
173			error = lookup(lf, symidx, 1, &addr);
174			if (error != 0)
175				return -1;
176			*where += addr;
177			break;
178
179		case R_ARM_COPY:	/* none */
180			/*
181			 * There shouldn't be copy relocations in kernel
182			 * objects.
183			 */
184			printf("kldload: unexpected R_COPY relocation\n");
185			return -1;
186			break;
187
188		case R_ARM_JUMP_SLOT:
189			error = lookup(lf, symidx, 1, &addr);
190			if (error == 0) {
191				*where = addr;
192				return (0);
193			}
194			return (-1);
195		case R_ARM_RELATIVE:
196			break;
197
198		default:
199			printf("kldload: unexpected relocation type %d\n",
200			       rtype);
201			return -1;
202	}
203	return(0);
204}
205
206int
207elf_reloc(linker_file_t lf, Elf_Addr relocbase, const void *data, int type,
208    elf_lookup_fn lookup)
209{
210
211	return (elf_reloc_internal(lf, relocbase, data, type, 0, lookup));
212}
213
214int
215elf_reloc_local(linker_file_t lf, Elf_Addr relocbase, const void *data,
216    int type, elf_lookup_fn lookup)
217{
218
219	return (elf_reloc_internal(lf, relocbase, data, type, 1, lookup));
220}
221
222int
223elf_cpu_load_file(linker_file_t lf __unused)
224{
225
226	/*
227	 * The pmap code does not do an icache sync upon establishing executable
228	 * mappings in the kernel pmap.  It's an optimization based on the fact
229	 * that kernel memory allocations always have EXECUTABLE protection even
230	 * when the memory isn't going to hold executable code.  The only time
231	 * kernel memory holding instructions does need a sync is after loading
232	 * a kernel module, and that's when this function gets called.  Normal
233	 * data cache maintenance has already been done by the IO code, and TLB
234	 * maintenance has been done by the pmap code, so all we have to do here
235	 * is invalidate the instruction cache (which also invalidates the
236	 * branch predictor cache on platforms that have one).
237	 */
238	cpu_icache_sync_all();
239	return (0);
240}
241
242int
243elf_cpu_unload_file(linker_file_t lf __unused)
244{
245
246	return (0);
247}
248