elf32_machdep.c revision 291420
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: head/sys/powerpc/powerpc/elf32_machdep.c 291420 2015-11-28 08:49:07Z kib $
26 */
27
28#include <sys/param.h>
29#include <sys/kernel.h>
30#include <sys/systm.h>
31
32#define __ELF_WORD_SIZE 32
33
34#include <sys/exec.h>
35#include <sys/imgact.h>
36#include <sys/malloc.h>
37#include <sys/proc.h>
38#include <sys/namei.h>
39#include <sys/fcntl.h>
40#include <sys/sysent.h>
41#include <sys/imgact_elf.h>
42#include <sys/syscall.h>
43#include <sys/signalvar.h>
44#include <sys/vnode.h>
45#include <sys/linker.h>
46
47#include <vm/vm.h>
48#include <vm/vm_param.h>
49
50#include <machine/altivec.h>
51#include <machine/cpu.h>
52#include <machine/elf.h>
53#include <machine/reg.h>
54#include <machine/md_var.h>
55
56#ifdef __powerpc64__
57#include <compat/freebsd32/freebsd32_proto.h>
58#include <compat/freebsd32/freebsd32_util.h>
59
60extern const char *freebsd32_syscallnames[];
61#endif
62
63struct sysentvec elf32_freebsd_sysvec = {
64	.sv_size	= SYS_MAXSYSCALL,
65#ifdef __powerpc64__
66	.sv_table	= freebsd32_sysent,
67#else
68	.sv_table	= sysent,
69#endif
70	.sv_mask	= 0,
71	.sv_errsize	= 0,
72	.sv_errtbl	= NULL,
73	.sv_transtrap	= NULL,
74	.sv_fixup	= __elfN(freebsd_fixup),
75	.sv_sendsig	= sendsig,
76	.sv_sigcode	= sigcode32,
77	.sv_szsigcode	= &szsigcode32,
78	.sv_name	= "FreeBSD ELF32",
79	.sv_coredump	= __elfN(coredump),
80	.sv_imgact_try	= NULL,
81	.sv_minsigstksz	= MINSIGSTKSZ,
82	.sv_pagesize	= PAGE_SIZE,
83	.sv_minuser	= VM_MIN_ADDRESS,
84	.sv_stackprot	= VM_PROT_ALL,
85#ifdef __powerpc64__
86	.sv_maxuser	= VM_MAXUSER_ADDRESS,
87	.sv_usrstack	= FREEBSD32_USRSTACK,
88	.sv_psstrings	= FREEBSD32_PS_STRINGS,
89	.sv_copyout_strings = freebsd32_copyout_strings,
90	.sv_setregs	= ppc32_setregs,
91	.sv_syscallnames = freebsd32_syscallnames,
92#else
93	.sv_maxuser	= VM_MAXUSER_ADDRESS,
94	.sv_usrstack	= USRSTACK,
95	.sv_psstrings	= PS_STRINGS,
96	.sv_copyout_strings = exec_copyout_strings,
97	.sv_setregs	= exec_setregs,
98	.sv_syscallnames = syscallnames,
99#endif
100	.sv_fixlimit	= NULL,
101	.sv_maxssiz	= NULL,
102	.sv_flags	= SV_ABI_FREEBSD | SV_ILP32 | SV_SHP,
103	.sv_set_syscall_retval = cpu_set_syscall_retval,
104	.sv_fetch_syscall_args = cpu_fetch_syscall_args,
105	.sv_shared_page_base = FREEBSD32_SHAREDPAGE,
106	.sv_shared_page_len = PAGE_SIZE,
107	.sv_schedtail	= NULL,
108	.sv_thread_detach = NULL,
109};
110INIT_SYSENTVEC(elf32_sysvec, &elf32_freebsd_sysvec);
111
112static Elf32_Brandinfo freebsd_brand_info = {
113	.brand		= ELFOSABI_FREEBSD,
114	.machine	= EM_PPC,
115	.compat_3_brand	= "FreeBSD",
116	.emul_path	= NULL,
117	.interp_path	= "/libexec/ld-elf.so.1",
118	.sysvec		= &elf32_freebsd_sysvec,
119#ifdef __powerpc64__
120	.interp_newpath	= "/libexec/ld-elf32.so.1",
121#else
122	.interp_newpath	= NULL,
123#endif
124	.brand_note	= &elf32_freebsd_brandnote,
125	.flags		= BI_CAN_EXEC_DYN | BI_BRAND_NOTE
126};
127
128SYSINIT(elf32, SI_SUB_EXEC, SI_ORDER_FIRST,
129    (sysinit_cfunc_t) elf32_insert_brand_entry,
130    &freebsd_brand_info);
131
132static Elf32_Brandinfo freebsd_brand_oinfo = {
133	.brand		= ELFOSABI_FREEBSD,
134	.machine	= EM_PPC,
135	.compat_3_brand	= "FreeBSD",
136	.emul_path	= NULL,
137	.interp_path	= "/usr/libexec/ld-elf.so.1",
138	.sysvec		= &elf32_freebsd_sysvec,
139	.interp_newpath	= NULL,
140	.brand_note	= &elf32_freebsd_brandnote,
141	.flags		= BI_CAN_EXEC_DYN | BI_BRAND_NOTE
142};
143
144SYSINIT(oelf32, SI_SUB_EXEC, SI_ORDER_ANY,
145	(sysinit_cfunc_t) elf32_insert_brand_entry,
146	&freebsd_brand_oinfo);
147
148void elf_reloc_self(Elf_Dyn *dynp, Elf_Addr relocbase);
149
150void
151elf32_dump_thread(struct thread *td, void *dst, size_t *off)
152{
153	size_t len;
154	struct pcb *pcb;
155
156	len = 0;
157	pcb = td->td_pcb;
158	if (pcb->pcb_flags & PCB_VEC) {
159		save_vec_nodrop(td);
160		if (dst != NULL) {
161			len += elf32_populate_note(NT_PPC_VMX,
162			    &pcb->pcb_vec, dst,
163			    sizeof(pcb->pcb_vec), NULL);
164		} else
165			len += elf32_populate_note(NT_PPC_VMX, NULL, NULL,
166			    sizeof(pcb->pcb_vec), NULL);
167	}
168	*off = len;
169}
170
171#ifndef __powerpc64__
172/* Process one elf relocation with addend. */
173static int
174elf_reloc_internal(linker_file_t lf, Elf_Addr relocbase, const void *data,
175    int type, int local, elf_lookup_fn lookup)
176{
177	Elf_Addr *where;
178	Elf_Half *hwhere;
179	Elf_Addr addr;
180	Elf_Addr addend;
181	Elf_Word rtype, symidx;
182	const Elf_Rela *rela;
183	int error;
184
185	switch (type) {
186	case ELF_RELOC_REL:
187		panic("PPC only supports RELA relocations");
188		break;
189	case ELF_RELOC_RELA:
190		rela = (const Elf_Rela *)data;
191		where = (Elf_Addr *) ((uintptr_t)relocbase + rela->r_offset);
192		hwhere = (Elf_Half *) ((uintptr_t)relocbase + rela->r_offset);
193		addend = rela->r_addend;
194		rtype = ELF_R_TYPE(rela->r_info);
195		symidx = ELF_R_SYM(rela->r_info);
196		break;
197	default:
198		panic("elf_reloc: unknown relocation mode %d\n", type);
199	}
200
201	switch (rtype) {
202
203	case R_PPC_NONE:
204		break;
205
206	case R_PPC_ADDR32: /* word32 S + A */
207		error = lookup(lf, symidx, 1, &addr);
208		if (error != 0)
209			return -1;
210		*where = elf_relocaddr(lf, addr + addend);
211			break;
212
213	case R_PPC_ADDR16_LO: /* #lo(S) */
214		error = lookup(lf, symidx, 1, &addr);
215		if (error != 0)
216			return -1;
217		/*
218		 * addend values are sometimes relative to sections
219		 * (i.e. .rodata) in rela, where in reality they
220		 * are relative to relocbase. Detect this condition.
221		 */
222		if (addr > relocbase && addr <= (relocbase + addend))
223			addr = relocbase;
224		addr = elf_relocaddr(lf, addr + addend);
225		*hwhere = addr & 0xffff;
226		break;
227
228	case R_PPC_ADDR16_HA: /* #ha(S) */
229		error = lookup(lf, symidx, 1, &addr);
230		if (error != 0)
231			return -1;
232		/*
233		 * addend values are sometimes relative to sections
234		 * (i.e. .rodata) in rela, where in reality they
235		 * are relative to relocbase. Detect this condition.
236		 */
237		if (addr > relocbase && addr <= (relocbase + addend))
238			addr = relocbase;
239		addr = elf_relocaddr(lf, addr + addend);
240		*hwhere = ((addr >> 16) + ((addr & 0x8000) ? 1 : 0))
241		    & 0xffff;
242		break;
243
244	case R_PPC_RELATIVE: /* word32 B + A */
245		*where = elf_relocaddr(lf, relocbase + addend);
246		break;
247
248	default:
249		printf("kldload: unexpected relocation type %d\n",
250		    (int) rtype);
251		return -1;
252	}
253	return(0);
254}
255
256void
257elf_reloc_self(Elf_Dyn *dynp, Elf_Addr relocbase)
258{
259	Elf_Rela *rela = 0, *relalim;
260	Elf_Addr relasz = 0;
261	Elf_Addr *where;
262
263	/*
264	 * Extract the rela/relasz values from the dynamic section
265	 */
266	for (; dynp->d_tag != DT_NULL; dynp++) {
267		switch (dynp->d_tag) {
268		case DT_RELA:
269			rela = (Elf_Rela *)(relocbase+dynp->d_un.d_ptr);
270			break;
271		case DT_RELASZ:
272			relasz = dynp->d_un.d_val;
273			break;
274		}
275	}
276
277	/*
278	 * Relocate these values
279	 */
280	relalim = (Elf_Rela *)((caddr_t)rela + relasz);
281	for (; rela < relalim; rela++) {
282		if (ELF_R_TYPE(rela->r_info) != R_PPC_RELATIVE)
283			continue;
284		where = (Elf_Addr *)(relocbase + rela->r_offset);
285		*where = (Elf_Addr)(relocbase + rela->r_addend);
286	}
287}
288
289int
290elf_reloc(linker_file_t lf, Elf_Addr relocbase, const void *data, int type,
291    elf_lookup_fn lookup)
292{
293
294	return (elf_reloc_internal(lf, relocbase, data, type, 0, lookup));
295}
296
297int
298elf_reloc_local(linker_file_t lf, Elf_Addr relocbase, const void *data,
299    int type, elf_lookup_fn lookup)
300{
301
302	return (elf_reloc_internal(lf, relocbase, data, type, 1, lookup));
303}
304
305int
306elf_cpu_load_file(linker_file_t lf)
307{
308	/* Only sync the cache for non-kernel modules */
309	if (lf->id != 1)
310		__syncicache(lf->address, lf->size);
311	return (0);
312}
313
314int
315elf_cpu_unload_file(linker_file_t lf __unused)
316{
317
318	return (0);
319}
320#endif
321