1 /* Cell SPU GNU/Linux support -- shared library handling.
2 Copyright (C) 2009, 2010 Free Software Foundation, Inc.
4 Contributed by Ulrich Weigand <uweigand@de.ibm.com>.
6 This file is part of GDB.
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 3 of the License, or
11 (at your option) any later version.
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with this program. If not, see <http://www.gnu.org/licenses/>. */
23 #include "gdb_string.h"
24 #include "gdb_assert.h"
26 #include "arch-utils.h"
30 #include "solib-svr4.h"
35 #include "breakpoint.h"
36 #include "gdbthread.h"
40 /* Highest SPE id (file handle) the inferior may have. */
41 #define MAX_SPE_FD 1024
43 /* Stand-alone SPE executable? */
44 #define spu_standalone_p() \
45 (symfile_objfile && symfile_objfile->obfd \
46 && bfd_get_arch (symfile_objfile->obfd) == bfd_arch_spu)
49 /* Relocate main SPE executable. */
51 spu_relocate_main_executable (int spufs_fd)
53 struct section_offsets *new_offsets;
56 if (symfile_objfile == NULL)
59 new_offsets = alloca (symfile_objfile->num_sections
60 * sizeof (struct section_offsets));
62 for (i = 0; i < symfile_objfile->num_sections; i++)
63 new_offsets->offsets[i] = SPUADDR (spufs_fd, 0);
65 objfile_relocate (symfile_objfile, new_offsets);
68 /* When running a stand-alone SPE executable, we may need to skip one more
69 exec event on startup, to get past the binfmt_misc loader. */
71 spu_skip_standalone_loader (void)
73 if (target_has_execution && !current_inferior ()->attach_flag)
75 struct target_waitstatus ws;
77 /* Only some kernels report an extra SIGTRAP with the binfmt_misc
78 loader; others do not. In addition, if we have attached to an
79 already running inferior instead of starting a new one, we will
80 not see the extra SIGTRAP -- and we cannot readily distinguish
81 the two cases, in particular with the extended-remote target.
83 Thus we issue a single-step here. If no extra SIGTRAP was pending,
84 this will step past the first instruction of the stand-alone SPE
85 executable loader, but we don't care about that. */
87 inferior_thread ()->in_infcall = 1; /* Suppress MI messages. */
89 target_resume (inferior_ptid, 1, TARGET_SIGNAL_0);
90 target_wait (minus_one_ptid, &ws, 0);
91 set_executing (minus_one_ptid, 0);
93 inferior_thread ()->in_infcall = 0;
97 /* Build a list of `struct so_list' objects describing the shared
98 objects currently loaded in the inferior. */
99 static struct so_list *
100 spu_current_sos (void)
102 enum bfd_endian byte_order = gdbarch_byte_order (target_gdbarch);
103 struct so_list *head;
104 struct so_list **link_ptr;
106 char buf[MAX_SPE_FD * 4];
109 /* First, retrieve the SVR4 shared library list. */
110 head = svr4_so_ops.current_sos ();
112 /* Append our libraries to the end of the list. */
113 for (link_ptr = &head; *link_ptr; link_ptr = &(*link_ptr)->next)
116 /* Determine list of SPU ids. */
117 size = target_read (¤t_target, TARGET_OBJECT_SPU, NULL,
120 /* Do not add stand-alone SPE executable context as shared library,
121 but relocate main SPE executable objfile. */
122 if (spu_standalone_p ())
126 int fd = extract_unsigned_integer (buf, 4, byte_order);
127 spu_relocate_main_executable (fd);
129 /* Re-enable breakpoints after main SPU context was established;
130 see also comments in spu_solib_create_inferior_hook. */
131 enable_breakpoints_after_startup ();
137 /* Create an so_list entry for each SPU id. */
138 for (i = 0; i < size; i += 4)
140 int fd = extract_unsigned_integer (buf + i, 4, byte_order);
143 unsigned long long addr;
144 char annex[32], id[100];
147 /* Read object ID. There's a race window where the inferior may have
148 already created the SPE context, but not installed the object-id
149 yet. Skip such entries; we'll be back for them later. */
150 xsnprintf (annex, sizeof annex, "%d/object-id", fd);
151 len = target_read (¤t_target, TARGET_OBJECT_SPU, annex,
153 if (len <= 0 || len >= sizeof id)
156 if (sscanf (id, "0x%llx", &addr) != 1 || !addr)
159 /* Allocate so_list structure. */
160 new = XZALLOC (struct so_list);
162 /* Encode FD and object ID in path name. Choose the name so as not
163 to conflict with any (normal) SVR4 library path name. */
164 xsnprintf (new->so_name, sizeof new->so_name, "@0x%llx <%d>", addr, fd);
165 strcpy (new->so_original_name, new->so_name);
168 link_ptr = &new->next;
174 /* Free so_list information. */
176 spu_free_so (struct so_list *so)
178 if (so->so_original_name[0] != '@')
179 svr4_so_ops.free_so (so);
182 /* Relocate section addresses. */
184 spu_relocate_section_addresses (struct so_list *so,
185 struct target_section *sec)
187 if (so->so_original_name[0] != '@')
188 svr4_so_ops.relocate_section_addresses (so, sec);
191 unsigned long long addr;
194 /* Set addr_low/high to just LS offset for display. */
195 if (so->addr_low == 0 && so->addr_high == 0
196 && strcmp (sec->the_bfd_section->name, ".text") == 0)
198 so->addr_low = sec->addr;
199 so->addr_high = sec->endaddr;
202 /* Decode object ID. */
203 if (sscanf (so->so_original_name, "@0x%llx <%d>", &addr, &fd) != 2)
204 internal_error (__FILE__, __LINE__, "bad object ID");
206 sec->addr = SPUADDR (fd, sec->addr);
207 sec->endaddr = SPUADDR (fd, sec->endaddr);
212 /* Inferior memory should contain an SPE executable image at location ADDR.
213 Allocate a BFD representing that executable. Return NULL on error. */
216 spu_bfd_iovec_open (bfd *nbfd, void *open_closure)
222 spu_bfd_iovec_close (bfd *nbfd, void *stream)
229 spu_bfd_iovec_pread (bfd *abfd, void *stream, void *buf,
230 file_ptr nbytes, file_ptr offset)
232 CORE_ADDR addr = *(CORE_ADDR *)stream;
235 ret = target_read_memory (addr + offset, buf, nbytes);
238 bfd_set_error (bfd_error_invalid_operation);
246 spu_bfd_iovec_stat (bfd *abfd, void *stream, struct stat *sb)
248 /* We don't have an easy way of finding the size of embedded spu
249 images. We could parse the in-memory ELF header and section
250 table to find the extent of the last section but that seems
251 pointless when the size is needed only for checks of other
252 parsed values in dbxread.c. */
253 sb->st_size = INT_MAX;
258 spu_bfd_fopen (char *name, CORE_ADDR addr)
262 CORE_ADDR *open_closure = xmalloc (sizeof (CORE_ADDR));
263 *open_closure = addr;
265 nbfd = bfd_openr_iovec (xstrdup (name), "elf32-spu",
266 spu_bfd_iovec_open, open_closure,
267 spu_bfd_iovec_pread, spu_bfd_iovec_close,
272 if (!bfd_check_format (nbfd, bfd_object))
281 /* Open shared library BFD. */
283 spu_bfd_open (char *pathname)
285 char *original_name = strrchr (pathname, '@');
288 unsigned long long addr;
291 /* Handle regular SVR4 libraries. */
293 return svr4_so_ops.bfd_open (pathname);
295 /* Decode object ID. */
296 if (sscanf (original_name, "@0x%llx <%d>", &addr, &fd) != 2)
297 internal_error (__FILE__, __LINE__, "bad object ID");
299 /* Open BFD representing SPE executable. */
300 abfd = spu_bfd_fopen (original_name, (CORE_ADDR) addr);
302 error (_("Cannot read SPE executable at %s"), original_name);
304 /* Retrieve SPU name note. */
305 spu_name = bfd_get_section_by_name (abfd, ".note.spu_name");
308 int sect_size = bfd_section_size (abfd, spu_name);
311 char *buf = alloca (sect_size - 20 + strlen (original_name) + 1);
312 bfd_get_section_contents (abfd, spu_name, buf, 20, sect_size - 20);
313 buf[sect_size - 20] = '\0';
315 strcat (buf, original_name);
317 xfree ((char *)abfd->filename);
318 abfd->filename = xstrdup (buf);
325 /* Lookup global symbol in a SPE executable. */
326 static struct symbol *
327 spu_lookup_lib_symbol (const struct objfile *objfile,
329 const domain_enum domain)
331 if (bfd_get_arch (objfile->obfd) == bfd_arch_spu)
332 return lookup_global_symbol_from_objfile (objfile, name, domain);
334 if (svr4_so_ops.lookup_lib_global_symbol != NULL)
335 return svr4_so_ops.lookup_lib_global_symbol (objfile, name, domain);
339 /* Enable shared library breakpoint. */
341 spu_enable_break (struct objfile *objfile)
343 struct minimal_symbol *spe_event_sym = NULL;
345 /* The libspe library will call __spe_context_update_event whenever any
346 SPE context is allocated or destroyed. */
347 spe_event_sym = lookup_minimal_symbol ("__spe_context_update_event",
350 /* Place a solib_event breakpoint on the symbol. */
353 CORE_ADDR addr = SYMBOL_VALUE_ADDRESS (spe_event_sym);
354 addr = gdbarch_convert_from_func_ptr_addr (target_gdbarch, addr,
356 create_solib_event_breakpoint (target_gdbarch, addr);
363 /* Create inferior hook. */
365 spu_solib_create_inferior_hook (int from_tty)
367 /* Handle SPE stand-alone executables. */
368 if (spu_standalone_p ())
370 /* After an SPE stand-alone executable was loaded, we'll receive
371 an additional trap due to the binfmt_misc handler. Make sure
372 to skip that trap. */
373 spu_skip_standalone_loader ();
375 /* If the user established breakpoints before starting the inferior, GDB
376 would attempt to insert those now. This would fail because the SPU
377 context has not yet been created and the SPU executable has not yet
378 been loaded. To prevent such failures, we disable all user-created
379 breakpoints now; they will be re-enabled in spu_current_sos once the
380 main SPU context has been detected. */
381 disable_breakpoints_before_startup ();
383 /* A special case arises when re-starting an executable, because at
384 this point it still resides at the relocated address range that was
385 determined during its last execution. We need to undo the relocation
386 so that that multi-architecture target recognizes the stand-alone
387 initialization special case. */
388 spu_relocate_main_executable (-1);
391 /* Call SVR4 hook -- this will re-insert the SVR4 solib breakpoints. */
392 svr4_so_ops.solib_create_inferior_hook (from_tty);
394 /* If the inferior is statically linked against libspe, we need to install
395 our own solib breakpoint right now. Otherwise, it will be installed by
396 the solib_loaded observer below as soon as libspe is loaded. */
397 spu_enable_break (NULL);
400 /* Install SPE "shared library" handling. This is called by -tdep code
401 that wants to support SPU as a secondary architecture. */
403 set_spu_solib_ops (struct gdbarch *gdbarch)
405 static struct target_so_ops spu_so_ops;
407 /* Initialize this lazily, to avoid an initialization order
408 dependency on solib-svr4.c's _initialize routine. */
409 if (spu_so_ops.current_sos == NULL)
411 spu_so_ops = svr4_so_ops;
412 spu_so_ops.solib_create_inferior_hook = spu_solib_create_inferior_hook;
413 spu_so_ops.relocate_section_addresses = spu_relocate_section_addresses;
414 spu_so_ops.free_so = spu_free_so;
415 spu_so_ops.current_sos = spu_current_sos;
416 spu_so_ops.bfd_open = spu_bfd_open;
417 spu_so_ops.lookup_lib_global_symbol = spu_lookup_lib_symbol;
420 set_solib_ops (gdbarch, &spu_so_ops);
423 /* Observer for the solib_loaded event. Used to install our breakpoint
424 if libspe is a shared library. */
426 spu_solib_loaded (struct so_list *so)
428 if (strstr (so->so_original_name, "/libspe") != NULL)
430 solib_read_symbols (so, so->from_tty ? SYMFILE_VERBOSE : 0);
431 spu_enable_break (so->objfile);
436 _initialize_spu_solib (void)
438 observer_attach_solib_loaded (spu_solib_loaded);