xref: /titanic_41/usr/src/lib/libproc/sparc/Pisadep.c (revision 3e3d658f8af590806331539f141881e82c204c61)
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 (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 /*
22  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 #include <sys/stack.h>
27 #include <sys/regset.h>
28 #include <sys/frame.h>
29 #include <sys/sysmacros.h>
30 #include <sys/machelf.h>
31 
32 #include <stdlib.h>
33 #include <unistd.h>
34 #include <sys/types.h>
35 #include <errno.h>
36 #include <string.h>
37 
38 #include "Pcontrol.h"
39 #include "Pstack.h"
40 #include "Pisadep.h"
41 
42 #define	SYSCALL32 0x91d02008	/* 32-bit syscall (ta 8) instruction */
43 
44 #ifndef	WINDOWSIZE32
45 #define	WINDOWSIZE32	(16 * sizeof (int32_t))
46 #endif
47 
48 const char *
49 Ppltdest(struct ps_prochandle *P, uintptr_t pltaddr)
50 {
51 	map_info_t *mp = Paddr2mptr(P, pltaddr);
52 
53 	uintptr_t r_addr;
54 	file_info_t *fp;
55 	Elf32_Rela r;
56 	size_t i;
57 
58 	if (mp == NULL || (fp = mp->map_file) == NULL ||
59 	    fp->file_plt_base == 0 || pltaddr < fp->file_plt_base ||
60 	    pltaddr >= fp->file_plt_base + fp->file_plt_size) {
61 		errno = EINVAL;
62 		return (NULL);
63 	}
64 
65 	i = (pltaddr - fp->file_plt_base -
66 	    M_PLT_XNumber * M32_PLT_ENTSIZE) / M32_PLT_ENTSIZE;
67 
68 	r_addr = fp->file_jmp_rel + i * sizeof (Elf32_Rela);
69 
70 	if (Pread(P, &r, sizeof (r), r_addr) == sizeof (r) &&
71 	    (i = ELF32_R_SYM(r.r_info)) < fp->file_dynsym.sym_symn) {
72 
73 		Elf_Data *data = fp->file_dynsym.sym_data_pri;
74 		Elf32_Sym *symp = &(((Elf32_Sym *)data->d_buf)[i]);
75 
76 		return (fp->file_dynsym.sym_strs + symp->st_name);
77 	}
78 
79 	return (NULL);
80 }
81 
82 int
83 Pissyscall(struct ps_prochandle *P, uintptr_t addr)
84 {
85 	instr_t sysinstr;
86 	instr_t instr;
87 
88 	sysinstr = SYSCALL32;
89 
90 	if (Pread(P, &instr, sizeof (instr), addr) != sizeof (instr) ||
91 	    instr != sysinstr)
92 		return (0);
93 	else
94 		return (1);
95 }
96 
97 int
98 Pissyscall_prev(struct ps_prochandle *P, uintptr_t addr, uintptr_t *dst)
99 {
100 	uintptr_t prevaddr = addr - sizeof (instr_t);
101 
102 	if (Pissyscall(P, prevaddr)) {
103 		if (dst)
104 			*dst = prevaddr;
105 		return (1);
106 	}
107 
108 	return (0);
109 }
110 
111 /* ARGSUSED */
112 int
113 Pissyscall_text(struct ps_prochandle *P, const void *buf, size_t buflen)
114 {
115 	instr_t sysinstr;
116 
117 	sysinstr = SYSCALL32;
118 
119 	if (buflen >= sizeof (instr_t) &&
120 	    memcmp(buf, &sysinstr, sizeof (instr_t)) == 0)
121 		return (1);
122 	else
123 		return (0);
124 }
125 
126 /*
127  * For gwindows_t support, we define a structure to pass arguments to
128  * a Plwp_iter() callback routine.
129  */
130 typedef struct {
131 	struct ps_prochandle *gq_proc;	/* libproc handle */
132 	struct rwindow *gq_rwin;	/* rwindow destination buffer */
133 	uintptr_t gq_addr;		/* stack address to match */
134 } gwin_query_t;
135 
136 static int
137 find_gwin(gwin_query_t *gqp, const lwpstatus_t *psp)
138 {
139 	gwindows_t gwin;
140 	struct stat64 st;
141 	char path[64];
142 	ssize_t n;
143 	int fd, i;
144 	int rv = 0; /* Return value for skip to next lwp */
145 
146 	(void) snprintf(path, sizeof (path), "/proc/%d/lwp/%d/gwindows",
147 	    (int)gqp->gq_proc->pid, (int)psp->pr_lwpid);
148 
149 	if (stat64(path, &st) == -1 || st.st_size == 0)
150 		return (0); /* Nothing doing; skip to next lwp */
151 
152 	if ((fd = open64(path, O_RDONLY)) >= 0) {
153 		/*
154 		 * Zero out the gwindows_t because the gwindows file only has
155 		 * as much data as needed to represent the saved windows.
156 		 */
157 		(void) memset(&gwin, 0, sizeof (gwin));
158 		n = read(fd, &gwin, sizeof (gwin));
159 
160 		if (n > 0) {
161 			/*
162 			 * If we actually found a non-zero gwindows file and
163 			 * were able to read it, iterate through the buffers
164 			 * looking for a stack pointer match; if one is found,
165 			 * copy out the corresponding register window.
166 			 */
167 			for (i = 0; i < gwin.wbcnt; i++) {
168 				if (gwin.spbuf[i] == (greg_t *)gqp->gq_addr) {
169 					(void) memcpy(gqp->gq_rwin,
170 					    &gwin.wbuf[i],
171 					    sizeof (struct rwindow));
172 
173 					rv = 1; /* We're done */
174 					break;
175 				}
176 			}
177 		}
178 		(void) close(fd);
179 	}
180 
181 	return (rv);
182 }
183 
184 static int
185 read_gwin(struct ps_prochandle *P, struct rwindow *rwp, uintptr_t sp)
186 {
187 	gwin_query_t gq;
188 
189 	if (P->state == PS_DEAD) {
190 		core_info_t *core = P->data;
191 		lwp_info_t *lwp = list_next(&core->core_lwp_head);
192 		uint_t n;
193 		int i;
194 
195 		for (n = 0; n < core->core_nlwp; n++, lwp = list_next(lwp)) {
196 			gwindows_t *gwin = lwp->lwp_gwins;
197 
198 			if (gwin == NULL)
199 				continue; /* No gwindows for this lwp */
200 
201 			/*
202 			 * If this lwp has gwindows associated with it, iterate
203 			 * through the buffers looking for a stack pointer
204 			 * match; if one is found, copy out the register window.
205 			 */
206 			for (i = 0; i < gwin->wbcnt; i++) {
207 				if (gwin->spbuf[i] == (greg_t *)sp) {
208 					(void) memcpy(rwp, &gwin->wbuf[i],
209 					    sizeof (struct rwindow));
210 					return (0); /* We're done */
211 				}
212 			}
213 		}
214 
215 		return (-1); /* No gwindows match found */
216 
217 	}
218 
219 	gq.gq_proc = P;
220 	gq.gq_rwin = rwp;
221 	gq.gq_addr = sp;
222 
223 	return (Plwp_iter(P, (proc_lwp_f *)find_gwin, &gq) ? 0 : -1);
224 }
225 
226 static void
227 ucontext_n_to_prgregs(const ucontext_t *src, prgregset_t dst)
228 {
229 	const greg_t *gregs = &src->uc_mcontext.gregs[0];
230 
231 	dst[R_PSR] = gregs[REG_PSR];
232 	dst[R_PC] = gregs[REG_PC];
233 	dst[R_nPC] = gregs[REG_nPC];
234 	dst[R_Y] = gregs[REG_Y];
235 
236 	dst[R_G1] = gregs[REG_G1];
237 	dst[R_G2] = gregs[REG_G2];
238 	dst[R_G3] = gregs[REG_G3];
239 	dst[R_G4] = gregs[REG_G4];
240 	dst[R_G5] = gregs[REG_G5];
241 	dst[R_G6] = gregs[REG_G6];
242 	dst[R_G7] = gregs[REG_G7];
243 
244 	dst[R_O0] = gregs[REG_O0];
245 	dst[R_O1] = gregs[REG_O1];
246 	dst[R_O2] = gregs[REG_O2];
247 	dst[R_O3] = gregs[REG_O3];
248 	dst[R_O4] = gregs[REG_O4];
249 	dst[R_O5] = gregs[REG_O5];
250 	dst[R_O6] = gregs[REG_O6];
251 	dst[R_O7] = gregs[REG_O7];
252 }
253 
254 int
255 Pstack_iter(struct ps_prochandle *P, const prgregset_t regs,
256 	proc_stack_f *func, void *arg)
257 {
258 	prgreg_t *prevfp = NULL;
259 	uint_t pfpsize = 0;
260 	int nfp = 0;
261 	prgregset_t gregs;
262 	long args[6];
263 	prgreg_t fp;
264 	int i;
265 	int rv;
266 	uintptr_t sp;
267 	ssize_t n;
268 	uclist_t ucl;
269 	ucontext_t uc;
270 
271 	init_uclist(&ucl, P);
272 	(void) memcpy(gregs, regs, sizeof (gregs));
273 
274 	for (;;) {
275 		fp = gregs[R_FP];
276 		if (stack_loop(fp, &prevfp, &nfp, &pfpsize))
277 			break;
278 
279 		for (i = 0; i < 6; i++)
280 			args[i] = gregs[R_I0 + i];
281 		if ((rv = func(arg, gregs, 6, args)) != 0)
282 			break;
283 
284 		gregs[R_PC] = gregs[R_I7];
285 		gregs[R_nPC] = gregs[R_PC] + 4;
286 		(void) memcpy(&gregs[R_O0], &gregs[R_I0], 8*sizeof (prgreg_t));
287 		if ((sp = gregs[R_FP]) == 0)
288 			break;
289 
290 		sp += STACK_BIAS;
291 
292 		if (find_uclink(&ucl, sp + SA(sizeof (struct frame))) &&
293 		    Pread(P, &uc, sizeof (uc), sp +
294 		    SA(sizeof (struct frame))) == sizeof (uc)) {
295 			ucontext_n_to_prgregs(&uc, gregs);
296 			sp = gregs[R_SP] + STACK_BIAS;
297 		}
298 
299 		n = Pread(P, &gregs[R_L0], sizeof (struct rwindow), sp);
300 
301 		if (n == sizeof (struct rwindow))
302 			continue;
303 
304 		/*
305 		 * If we get here, then our Pread of the register window
306 		 * failed.  If this is because the address was not mapped,
307 		 * then we attempt to read this window via any gwindows
308 		 * information we have.  If that too fails, abort our loop.
309 		 */
310 		if (n > 0)
311 			break;	/* Failed for reason other than not mapped */
312 
313 		if (read_gwin(P, (struct rwindow *)&gregs[R_L0], sp) == -1)
314 			break;	/* No gwindows match either */
315 	}
316 
317 	if (prevfp)
318 		free(prevfp);
319 
320 	free_uclist(&ucl);
321 	return (rv);
322 }
323 
324 uintptr_t
325 Psyscall_setup(struct ps_prochandle *P, int nargs, int sysindex, uintptr_t sp)
326 {
327 	sp -= (nargs > 6)?
328 	    WINDOWSIZE32 + sizeof (int32_t) * (1 + nargs) :
329 	    WINDOWSIZE32 + sizeof (int32_t) * (1 + 6);
330 	sp = PSTACK_ALIGN32(sp);
331 
332 	P->status.pr_lwp.pr_reg[R_G1] = sysindex;
333 	P->status.pr_lwp.pr_reg[R_SP] = sp;
334 	P->status.pr_lwp.pr_reg[R_PC] = P->sysaddr;
335 	P->status.pr_lwp.pr_reg[R_nPC] = P->sysaddr + sizeof (instr_t);
336 
337 	return (sp + WINDOWSIZE32 + sizeof (int32_t));
338 }
339 
340 int
341 Psyscall_copyinargs(struct ps_prochandle *P, int nargs, argdes_t *argp,
342     uintptr_t ap)
343 {
344 	uint32_t arglist[MAXARGS+2];
345 	int i;
346 	argdes_t *adp;
347 
348 	for (i = 0, adp = argp; i < nargs; i++, adp++) {
349 		arglist[i] = adp->arg_value;
350 
351 		if (i < 6)
352 			(void) Pputareg(P, R_O0+i, adp->arg_value);
353 	}
354 
355 	if (nargs > 6 &&
356 	    Pwrite(P, &arglist[0], sizeof (int32_t) * nargs,
357 	    (uintptr_t)ap) != sizeof (int32_t) * nargs)
358 		return (-1);
359 
360 	return (0);
361 }
362 
363 /* ARGSUSED */
364 int
365 Psyscall_copyoutargs(struct ps_prochandle *P, int nargs, argdes_t *argp,
366     uintptr_t ap)
367 {
368 	/* Do nothing */
369 	return (0);
370 }
371