xref: /illumos-gate/usr/src/lib/libproc/sparc/Pisadep.c (revision 7c478bd95313f5f23a4c958a745db2134aa03244)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*
23  * Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #pragma ident	"%Z%%M%	%I%	%E% SMI"
28 
29 #include <sys/stack.h>
30 #include <sys/regset.h>
31 #include <sys/frame.h>
32 #include <sys/sysmacros.h>
33 
34 #include <stdlib.h>
35 #include <unistd.h>
36 #include <sys/types.h>
37 #include <errno.h>
38 #include <string.h>
39 
40 #include "Pcontrol.h"
41 #include "Pstack.h"
42 #include "Pisadep.h"
43 
44 #define	M_PLT_NRSV	4			/* reserved PLT entries */
45 #define	M_PLT_ENTSIZE	12			/* size of each PLT entry */
46 
47 #define	SYSCALL32 0x91d02008	/* 32-bit syscall (ta 8) instruction */
48 
49 #ifndef	WINDOWSIZE32
50 #define	WINDOWSIZE32	(16 * sizeof (int32_t))
51 #endif
52 
53 const char *
54 Ppltdest(struct ps_prochandle *P, uintptr_t pltaddr)
55 {
56 	map_info_t *mp = Paddr2mptr(P, pltaddr);
57 
58 	uintptr_t r_addr;
59 	file_info_t *fp;
60 	Elf32_Rela r;
61 	size_t i;
62 
63 	if (mp == NULL || (fp = mp->map_file) == NULL ||
64 	    fp->file_plt_base == 0 || pltaddr < fp->file_plt_base ||
65 	    pltaddr >= fp->file_plt_base + fp->file_plt_size) {
66 		errno = EINVAL;
67 		return (NULL);
68 	}
69 
70 	i = (pltaddr - fp->file_plt_base -
71 	    M_PLT_NRSV * M_PLT_ENTSIZE) / M_PLT_ENTSIZE;
72 
73 	r_addr = fp->file_jmp_rel + i * sizeof (Elf32_Rela);
74 
75 	if (Pread(P, &r, sizeof (r), r_addr) == sizeof (r) &&
76 	    (i = ELF32_R_SYM(r.r_info)) < fp->file_dynsym.sym_symn) {
77 
78 		Elf_Data *data = fp->file_dynsym.sym_data;
79 		Elf32_Sym *symp = &(((Elf32_Sym *)data->d_buf)[i]);
80 
81 		return (fp->file_dynsym.sym_strs + symp->st_name);
82 	}
83 
84 	return (NULL);
85 }
86 
87 int
88 Pissyscall(struct ps_prochandle *P, uintptr_t addr)
89 {
90 	instr_t sysinstr;
91 	instr_t instr;
92 
93 	sysinstr = SYSCALL32;
94 
95 	if (Pread(P, &instr, sizeof (instr), addr) != sizeof (instr) ||
96 	    instr != sysinstr)
97 		return (0);
98 	else
99 		return (1);
100 }
101 
102 int
103 Pissyscall_prev(struct ps_prochandle *P, uintptr_t addr, uintptr_t *dst)
104 {
105 	uintptr_t prevaddr = addr - sizeof (instr_t);
106 
107 	if (Pissyscall(P, prevaddr)) {
108 		if (dst)
109 			*dst = prevaddr;
110 		return (1);
111 	}
112 
113 	return (0);
114 }
115 
116 /* ARGSUSED */
117 int
118 Pissyscall_text(struct ps_prochandle *P, const void *buf, size_t buflen)
119 {
120 	instr_t sysinstr;
121 
122 	sysinstr = SYSCALL32;
123 
124 	if (buflen >= sizeof (instr_t) &&
125 	    memcmp(buf, &sysinstr, sizeof (instr_t)) == 0)
126 		return (1);
127 	else
128 		return (0);
129 }
130 
131 /*
132  * For gwindows_t support, we define a structure to pass arguments to
133  * a Plwp_iter() callback routine.
134  */
135 typedef struct {
136 	struct ps_prochandle *gq_proc;	/* libproc handle */
137 	struct rwindow *gq_rwin;	/* rwindow destination buffer */
138 	uintptr_t gq_addr;		/* stack address to match */
139 } gwin_query_t;
140 
141 static int
142 find_gwin(gwin_query_t *gqp, const lwpstatus_t *psp)
143 {
144 	gwindows_t gwin;
145 	struct stat64 st;
146 	char path[64];
147 	ssize_t n;
148 	int fd, i;
149 	int rv = 0; /* Return value for skip to next lwp */
150 
151 	(void) snprintf(path, sizeof (path), "/proc/%d/lwp/%d/gwindows",
152 	    (int)gqp->gq_proc->pid, (int)psp->pr_lwpid);
153 
154 	if (stat64(path, &st) == -1 || st.st_size == 0)
155 		return (0); /* Nothing doing; skip to next lwp */
156 
157 	if ((fd = open64(path, O_RDONLY)) >= 0) {
158 		/*
159 		 * Zero out the gwindows_t because the gwindows file only has
160 		 * as much data as needed to represent the saved windows.
161 		 */
162 		(void) memset(&gwin, 0, sizeof (gwin));
163 		n = read(fd, &gwin, sizeof (gwin));
164 
165 		if (n > 0) {
166 			/*
167 			 * If we actually found a non-zero gwindows file and
168 			 * were able to read it, iterate through the buffers
169 			 * looking for a stack pointer match; if one is found,
170 			 * copy out the corresponding register window.
171 			 */
172 			for (i = 0; i < gwin.wbcnt; i++) {
173 				if (gwin.spbuf[i] == (greg_t *)gqp->gq_addr) {
174 					(void) memcpy(gqp->gq_rwin,
175 					    &gwin.wbuf[i],
176 					    sizeof (struct rwindow));
177 
178 					rv = 1; /* We're done */
179 					break;
180 				}
181 			}
182 		}
183 		(void) close(fd);
184 	}
185 
186 	return (rv);
187 }
188 
189 static int
190 read_gwin(struct ps_prochandle *P, struct rwindow *rwp, uintptr_t sp)
191 {
192 	gwin_query_t gq;
193 
194 	if (P->state == PS_DEAD) {
195 		lwp_info_t *lwp = list_next(&P->core->core_lwp_head);
196 		uint_t n;
197 		int i;
198 
199 		for (n = 0; n < P->core->core_nlwp; n++, lwp = list_next(lwp)) {
200 			gwindows_t *gwin = lwp->lwp_gwins;
201 
202 			if (gwin == NULL)
203 				continue; /* No gwindows for this lwp */
204 
205 			/*
206 			 * If this lwp has gwindows associated with it, iterate
207 			 * through the buffers looking for a stack pointer
208 			 * match; if one is found, copy out the register window.
209 			 */
210 			for (i = 0; i < gwin->wbcnt; i++) {
211 				if (gwin->spbuf[i] == (greg_t *)sp) {
212 					(void) memcpy(rwp, &gwin->wbuf[i],
213 					    sizeof (struct rwindow));
214 					return (0); /* We're done */
215 				}
216 			}
217 		}
218 
219 		return (-1); /* No gwindows match found */
220 
221 	}
222 
223 	gq.gq_proc = P;
224 	gq.gq_rwin = rwp;
225 	gq.gq_addr = sp;
226 
227 	return (Plwp_iter(P, (proc_lwp_f *)find_gwin, &gq) ? 0 : -1);
228 }
229 
230 static void
231 ucontext_n_to_prgregs(const ucontext_t *src, prgregset_t dst)
232 {
233 	const greg_t *gregs = &src->uc_mcontext.gregs[0];
234 
235 	dst[R_PSR] = gregs[REG_PSR];
236 	dst[R_PC] = gregs[REG_PC];
237 	dst[R_nPC] = gregs[REG_nPC];
238 	dst[R_Y] = gregs[REG_Y];
239 
240 	dst[R_G1] = gregs[REG_G1];
241 	dst[R_G2] = gregs[REG_G2];
242 	dst[R_G3] = gregs[REG_G3];
243 	dst[R_G4] = gregs[REG_G4];
244 	dst[R_G5] = gregs[REG_G5];
245 	dst[R_G6] = gregs[REG_G6];
246 	dst[R_G7] = gregs[REG_G7];
247 
248 	dst[R_O0] = gregs[REG_O0];
249 	dst[R_O1] = gregs[REG_O1];
250 	dst[R_O2] = gregs[REG_O2];
251 	dst[R_O3] = gregs[REG_O3];
252 	dst[R_O4] = gregs[REG_O4];
253 	dst[R_O5] = gregs[REG_O5];
254 	dst[R_O6] = gregs[REG_O6];
255 	dst[R_O7] = gregs[REG_O7];
256 }
257 
258 int
259 Pstack_iter(struct ps_prochandle *P, const prgregset_t regs,
260 	proc_stack_f *func, void *arg)
261 {
262 	prgreg_t *prevfp = NULL;
263 	uint_t pfpsize = 0;
264 	int nfp = 0;
265 	prgregset_t gregs;
266 	long args[6];
267 	prgreg_t fp;
268 	int i;
269 	int rv;
270 	uintptr_t sp;
271 	ssize_t n;
272 	uclist_t ucl;
273 	ucontext_t uc;
274 
275 	init_uclist(&ucl, P);
276 	(void) memcpy(gregs, regs, sizeof (gregs));
277 
278 	for (;;) {
279 		fp = gregs[R_FP];
280 		if (stack_loop(fp, &prevfp, &nfp, &pfpsize))
281 			break;
282 
283 		for (i = 0; i < 6; i++)
284 			args[i] = gregs[R_I0 + i];
285 		if ((rv = func(arg, gregs, 6, args)) != 0)
286 			break;
287 
288 		gregs[R_PC] = gregs[R_I7];
289 		gregs[R_nPC] = gregs[R_PC] + 4;
290 		(void) memcpy(&gregs[R_O0], &gregs[R_I0], 8*sizeof (prgreg_t));
291 		if ((sp = gregs[R_FP]) == 0)
292 			break;
293 
294 		sp += STACK_BIAS;
295 
296 		if (find_uclink(&ucl, sp + SA(sizeof (struct frame))) &&
297 		    Pread(P, &uc, sizeof (uc), sp +
298 		    SA(sizeof (struct frame))) == sizeof (uc)) {
299 			ucontext_n_to_prgregs(&uc, gregs);
300 			sp = gregs[R_SP] + STACK_BIAS;
301 		}
302 
303 		n = Pread(P, &gregs[R_L0], sizeof (struct rwindow), sp);
304 
305 		if (n == sizeof (struct rwindow))
306 			continue;
307 
308 		/*
309 		 * If we get here, then our Pread of the register window
310 		 * failed.  If this is because the address was not mapped,
311 		 * then we attempt to read this window via any gwindows
312 		 * information we have.  If that too fails, abort our loop.
313 		 */
314 		if (n > 0)
315 			break;	/* Failed for reason other than not mapped */
316 
317 		if (read_gwin(P, (struct rwindow *)&gregs[R_L0], sp) == -1)
318 			break;	/* No gwindows match either */
319 	}
320 
321 	if (prevfp)
322 		free(prevfp);
323 
324 	free_uclist(&ucl);
325 	return (rv);
326 }
327 
328 uintptr_t
329 Psyscall_setup(struct ps_prochandle *P, int nargs, int sysindex, uintptr_t sp)
330 {
331 	sp -= (nargs > 6)?
332 		WINDOWSIZE32 + sizeof (int32_t) * (1 + nargs) :
333 		WINDOWSIZE32 + sizeof (int32_t) * (1 + 6);
334 	sp = PSTACK_ALIGN32(sp);
335 
336 	P->status.pr_lwp.pr_reg[R_G1] = sysindex;
337 	P->status.pr_lwp.pr_reg[R_SP] = sp;
338 	P->status.pr_lwp.pr_reg[R_PC] = P->sysaddr;
339 	P->status.pr_lwp.pr_reg[R_nPC] = P->sysaddr + sizeof (instr_t);
340 
341 	return (sp + WINDOWSIZE32 + sizeof (int32_t));
342 }
343 
344 int
345 Psyscall_copyinargs(struct ps_prochandle *P, int nargs, argdes_t *argp,
346     uintptr_t ap)
347 {
348 	uint32_t arglist[MAXARGS+2];
349 	int i;
350 	argdes_t *adp;
351 
352 	for (i = 0, adp = argp; i < nargs; i++, adp++) {
353 		arglist[i] = adp->arg_value;
354 
355 		if (i < 6)
356 			(void) Pputareg(P, R_O0+i, adp->arg_value);
357 	}
358 
359 	if (nargs > 6 &&
360 	    Pwrite(P, &arglist[0], sizeof (int32_t) * nargs,
361 	    (uintptr_t)ap) != sizeof (int32_t) * nargs)
362 		return (-1);
363 
364 	return (0);
365 }
366 
367 /* ARGSUSED */
368 int
369 Psyscall_copyoutargs(struct ps_prochandle *P, int nargs, argdes_t *argp,
370     uintptr_t ap)
371 {
372 	/* Do nothing */
373 	return (0);
374 }
375