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author | Christophe Lyon <christophe.lyon@linaro.org> | 2018-12-14 09:33:53 +0000 |
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committer | Christophe Lyon <christophe.lyon@linaro.org> | 2018-12-14 09:33:53 +0000 |
commit | 548c794021c606a2aae2cb9c44e2b0ac338a75d6 (patch) | |
tree | 7f637bfa80db3cf53fa69357af5fce8555cfcc0a | |
parent | 24bce9bbe510c9efa36c0f85fb2f8a93ec8b623e (diff) | |
download | gdb-548c794021c606a2aae2cb9c44e2b0ac338a75d6.zip gdb-548c794021c606a2aae2cb9c44e2b0ac338a75d6.tar.gz gdb-548c794021c606a2aae2cb9c44e2b0ac338a75d6.tar.bz2 |
ARM FDPIC: initial commit
-rw-r--r-- | gdb/Makefile.in | 1 | ||||
-rw-r--r-- | gdb/arm-linux-tdep.c | 10 | ||||
-rw-r--r-- | gdb/arm-tdep.h | 6 | ||||
-rw-r--r-- | gdb/configure.tgt | 6 | ||||
-rw-r--r-- | gdb/solib-fdpic.c | 1287 |
5 files changed, 1310 insertions, 0 deletions
diff --git a/gdb/Makefile.in b/gdb/Makefile.in index 3be058f..fa9037b 100644 --- a/gdb/Makefile.in +++ b/gdb/Makefile.in @@ -768,6 +768,7 @@ ALL_TARGET_OBS = \ solib-aix.o \ solib-darwin.o \ solib-dsbt.o \ + solib-fdpic.o \ solib-frv.o \ solib-spu.o \ solib-svr4.o \ diff --git a/gdb/arm-linux-tdep.c b/gdb/arm-linux-tdep.c index 78c4c80..a571e8b 100644 --- a/gdb/arm-linux-tdep.c +++ b/gdb/arm-linux-tdep.c @@ -25,6 +25,7 @@ #include "frame.h" #include "regcache.h" #include "solib-svr4.h" +#include "solib.h" #include "osabi.h" #include "regset.h" #include "trad-frame.h" @@ -1777,8 +1778,12 @@ arm_linux_init_abi (struct gdbarch_info info, } tdep->jb_elt_size = ARM_LINUX_JB_ELEMENT_SIZE; + if (tdep->is_fdpic) { + set_solib_ops (gdbarch, &fdpic_so_ops); + } else { set_solib_svr4_fetch_link_map_offsets (gdbarch, svr4_ilp32_fetch_link_map_offsets); + } /* Single stepping. */ set_gdbarch_software_single_step (gdbarch, arm_linux_software_single_step); @@ -1788,8 +1793,13 @@ arm_linux_init_abi (struct gdbarch_info info, set_gdbarch_skip_solib_resolver (gdbarch, glibc_skip_solib_resolver); /* Enable TLS support. */ + if (tdep->is_fdpic) { + set_gdbarch_fetch_tls_load_module_address (gdbarch, + fdpic_fetch_objfile_link_map); + } else { set_gdbarch_fetch_tls_load_module_address (gdbarch, svr4_fetch_objfile_link_map); + } tramp_frame_prepend_unwinder (gdbarch, &arm_linux_sigreturn_tramp_frame); diff --git a/gdb/arm-tdep.h b/gdb/arm-tdep.h index 8fa8b68..c85b60d 100644 --- a/gdb/arm-tdep.h +++ b/gdb/arm-tdep.h @@ -113,6 +113,7 @@ struct gdbarch_tdep int have_neon; /* Do we have a NEON unit? */ int is_m; /* Does the target follow the "M" profile. */ + int is_fdpic; /* Is the loaded binary a fdpic one. */ CORE_ADDR lowest_pc; /* Lowest address at which instructions will appear. */ @@ -297,4 +298,9 @@ extern struct target_desc *tdesc_arm_with_vfpv2; extern struct target_desc *tdesc_arm_with_vfpv3; extern struct target_desc *tdesc_arm_with_neon; +/* FDPIC structure and API. */ +extern struct target_so_ops fdpic_so_ops; +extern CORE_ADDR fdpic_fetch_objfile_link_map (struct objfile *objfile); +extern CORE_ADDR fdpic_find_global_pointer (CORE_ADDR addr); + #endif /* arm-tdep.h */ diff --git a/gdb/configure.tgt b/gdb/configure.tgt index 9b646fa..9e1805d 100644 --- a/gdb/configure.tgt +++ b/gdb/configure.tgt @@ -166,6 +166,12 @@ arm*-*-linux*) solib-svr4.o symfile-mem.o linux-tdep.o linux-record.o" build_gdbserver=yes ;; +arm*-*-uclinuxfdpiceabi) + # Target: ARM based machine running GNU/Linux + gdb_target_obs="arch/arm-linux.o arm-linux-tdep.o glibc-tdep.o \ + solib-svr4.o solib-fdpic.o symfile-mem.o linux-tdep.o linux-record.o" + # NO YET build_gdbserver=yes + ;; arm*-*-freebsd*) # Target: FreeBSD/arm gdb_target_obs="arm-fbsd-tdep.o" diff --git a/gdb/solib-fdpic.c b/gdb/solib-fdpic.c new file mode 100644 index 0000000..de530ce --- /dev/null +++ b/gdb/solib-fdpic.c @@ -0,0 +1,1287 @@ +/* Handle FR-V (FDPIC) shared libraries for GDB, the GNU Debugger. + Copyright (C) 2004-2018 Free Software Foundation, Inc. + + This file is part of GDB. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see <http://www.gnu.org/licenses/>. */ + + +#include "defs.h" +#include "inferior.h" +#include "gdbcore.h" +#include "solib.h" +#include "solist.h" +//#include "arm-tdep.h" +int fdpic_fdpic_loadmap_addresses (struct gdbarch *gdbarch, + CORE_ADDR *interp_addr, CORE_ADDR *exec_addr); +#include "objfiles.h" +#include "symtab.h" +#include "language.h" +#include "command.h" +#include "gdbcmd.h" +//#include "elf/frv.h" +#include "gdb_bfd.h" + +/* Flag which indicates whether internal debug messages should be printed. */ +static unsigned int solib_fdpic_debug; + +/* FR-V pointers are four bytes wide. */ +enum { FDPIC_PTR_SIZE = 4 }; + +/* Representation of loadmap and related structs for the FR-V FDPIC ABI. */ + +/* External versions; the size and alignment of the fields should be + the same as those on the target. When loaded, the placement of + the bits in each field will be the same as on the target. */ +typedef gdb_byte ext_Elf32_Half[2]; +typedef gdb_byte ext_Elf32_Addr[4]; +typedef gdb_byte ext_Elf32_Word[4]; + +struct ext_elf32_fdpic_loadseg +{ + /* Core address to which the segment is mapped. */ + ext_Elf32_Addr addr; + /* VMA recorded in the program header. */ + ext_Elf32_Addr p_vaddr; + /* Size of this segment in memory. */ + ext_Elf32_Word p_memsz; +}; + +struct ext_elf32_fdpic_loadmap { + /* Protocol version number, must be zero. */ + ext_Elf32_Half version; + /* Number of segments in this map. */ + ext_Elf32_Half nsegs; + /* The actual memory map. */ + struct ext_elf32_fdpic_loadseg segs[1 /* nsegs, actually */]; +}; + +/* Internal versions; the types are GDB types and the data in each + of the fields is (or will be) decoded from the external struct + for ease of consumption. */ +struct int_elf32_fdpic_loadseg +{ + /* Core address to which the segment is mapped. */ + CORE_ADDR addr; + /* VMA recorded in the program header. */ + CORE_ADDR p_vaddr; + /* Size of this segment in memory. */ + long p_memsz; +}; + +struct int_elf32_fdpic_loadmap { + /* Protocol version number, must be zero. */ + int version; + /* Number of segments in this map. */ + int nsegs; + /* The actual memory map. */ + struct int_elf32_fdpic_loadseg segs[1 /* nsegs, actually */]; +}; + +/* Given address LDMADDR, fetch and decode the loadmap at that address. + Return NULL if there is a problem reading the target memory or if + there doesn't appear to be a loadmap at the given address. The + allocated space (representing the loadmap) returned by this + function may be freed via a single call to xfree(). */ + +static struct int_elf32_fdpic_loadmap * +fetch_loadmap (CORE_ADDR ldmaddr) +{ + enum bfd_endian byte_order = gdbarch_byte_order (target_gdbarch ()); + struct ext_elf32_fdpic_loadmap ext_ldmbuf_partial; + struct ext_elf32_fdpic_loadmap *ext_ldmbuf; + struct int_elf32_fdpic_loadmap *int_ldmbuf; + int ext_ldmbuf_size, int_ldmbuf_size; + int version, seg, nsegs; + + /* Fetch initial portion of the loadmap. */ + if (target_read_memory (ldmaddr, (gdb_byte *) &ext_ldmbuf_partial, + sizeof ext_ldmbuf_partial)) + { + /* Problem reading the target's memory. */ + return NULL; + } + + /* Extract the version. */ + version = extract_unsigned_integer (ext_ldmbuf_partial.version, + sizeof ext_ldmbuf_partial.version, + byte_order); + if (version != 0) + { + /* We only handle version 0. */ + return NULL; + } + + /* Extract the number of segments. */ + nsegs = extract_unsigned_integer (ext_ldmbuf_partial.nsegs, + sizeof ext_ldmbuf_partial.nsegs, + byte_order); + + if (nsegs <= 0) + return NULL; + + /* Allocate space for the complete (external) loadmap. */ + ext_ldmbuf_size = sizeof (struct ext_elf32_fdpic_loadmap) + + (nsegs - 1) * sizeof (struct ext_elf32_fdpic_loadseg); + ext_ldmbuf = (struct ext_elf32_fdpic_loadmap *) xmalloc (ext_ldmbuf_size); + + /* Copy over the portion of the loadmap that's already been read. */ + memcpy (ext_ldmbuf, &ext_ldmbuf_partial, sizeof ext_ldmbuf_partial); + + /* Read the rest of the loadmap from the target. */ + if (target_read_memory (ldmaddr + sizeof ext_ldmbuf_partial, + (gdb_byte *) ext_ldmbuf + sizeof ext_ldmbuf_partial, + ext_ldmbuf_size - sizeof ext_ldmbuf_partial)) + { + /* Couldn't read rest of the loadmap. */ + xfree (ext_ldmbuf); + return NULL; + } + + /* Allocate space into which to put information extract from the + external loadsegs. I.e, allocate the internal loadsegs. */ + int_ldmbuf_size = sizeof (struct int_elf32_fdpic_loadmap) + + (nsegs - 1) * sizeof (struct int_elf32_fdpic_loadseg); + int_ldmbuf = (struct int_elf32_fdpic_loadmap *) xmalloc (int_ldmbuf_size); + + /* Place extracted information in internal structs. */ + int_ldmbuf->version = version; + int_ldmbuf->nsegs = nsegs; + for (seg = 0; seg < nsegs; seg++) + { + int_ldmbuf->segs[seg].addr + = extract_unsigned_integer (ext_ldmbuf->segs[seg].addr, + sizeof (ext_ldmbuf->segs[seg].addr), + byte_order); + int_ldmbuf->segs[seg].p_vaddr + = extract_unsigned_integer (ext_ldmbuf->segs[seg].p_vaddr, + sizeof (ext_ldmbuf->segs[seg].p_vaddr), + byte_order); + int_ldmbuf->segs[seg].p_memsz + = extract_unsigned_integer (ext_ldmbuf->segs[seg].p_memsz, + sizeof (ext_ldmbuf->segs[seg].p_memsz), + byte_order); + } + + xfree (ext_ldmbuf); + return int_ldmbuf; +} + +/* External link_map and elf32_fdpic_loadaddr struct definitions. */ + +typedef gdb_byte ext_ptr[4]; + +struct ext_elf32_fdpic_loadaddr +{ + ext_ptr map; /* struct elf32_fdpic_loadmap *map; */ + ext_ptr got_value; /* void *got_value; */ +}; + +struct ext_link_map +{ + struct ext_elf32_fdpic_loadaddr l_addr; + + /* Absolute file name object was found in. */ + ext_ptr l_name; /* char *l_name; */ + + /* Dynamic section of the shared object. */ + ext_ptr l_ld; /* ElfW(Dyn) *l_ld; */ + + /* Chain of loaded objects. */ + ext_ptr l_next, l_prev; /* struct link_map *l_next, *l_prev; */ +}; + +/* Link map info to include in an allocated so_list entry. */ + +struct lm_info_fdpic : public lm_info_base +{ + ~lm_info_fdpic () + { + xfree (this->map); + xfree (this->dyn_syms); + xfree (this->dyn_relocs); + } + + /* The loadmap, digested into an easier to use form. */ + int_elf32_fdpic_loadmap *map = NULL; + /* The GOT address for this link map entry. */ + CORE_ADDR got_value = 0; + /* The link map address, needed for fdpic_fetch_objfile_link_map(). */ + CORE_ADDR lm_addr = 0; + + /* Cached dynamic symbol table and dynamic relocs initialized and + used only by find_canonical_descriptor_in_load_object(). + + Note: kevinb/2004-02-26: It appears that calls to + bfd_canonicalize_dynamic_reloc() will use the same symbols as + those supplied to the first call to this function. Therefore, + it's important to NOT free the asymbol ** data structure + supplied to the first call. Thus the caching of the dynamic + symbols (dyn_syms) is critical for correct operation. The + caching of the dynamic relocations could be dispensed with. */ + asymbol **dyn_syms = NULL; + arelent **dyn_relocs = NULL; + int dyn_reloc_count = 0; /* Number of dynamic relocs. */ +}; + +/* The load map, got value, etc. are not available from the chain + of loaded shared objects. ``main_executable_lm_info'' provides + a way to get at this information so that it doesn't need to be + frequently recomputed. Initialized by fdpic_relocate_main_executable(). */ +static lm_info_fdpic *main_executable_lm_info; + +static void fdpic_relocate_main_executable (void); +static CORE_ADDR main_got (void); +static int enable_break2 (void); + +/* Implement the "open_symbol_file_object" target_so_ops method. */ + +static int +open_symbol_file_object (int from_tty) +{ + /* Unimplemented. */ + return 0; +} + +/* Cached value for lm_base(), below. */ +static CORE_ADDR lm_base_cache = 0; + +/* Link map address for main module. */ +static CORE_ADDR main_lm_addr = 0; + +/* Return the address from which the link map chain may be found. On + the FR-V, this may be found in a number of ways. Assuming that the + main executable has already been relocated, the easiest way to find + this value is to look up the address of _GLOBAL_OFFSET_TABLE_. A + pointer to the start of the link map will be located at the word found + at _GLOBAL_OFFSET_TABLE_ + 8. (This is part of the dynamic linker + reserve area mandated by the ABI.) */ + +static CORE_ADDR +lm_base (void) +{ + enum bfd_endian byte_order = gdbarch_byte_order (target_gdbarch ()); + struct bound_minimal_symbol got_sym; + CORE_ADDR addr; + gdb_byte buf[FDPIC_PTR_SIZE]; + + /* One of our assumptions is that the main executable has been relocated. + Bail out if this has not happened. (Note that post_create_inferior() + in infcmd.c will call solib_add prior to solib_create_inferior_hook(). + If we allow this to happen, lm_base_cache will be initialized with + a bogus value. */ + if (main_executable_lm_info == 0) + return 0; + + /* If we already have a cached value, return it. */ + if (lm_base_cache) + return lm_base_cache; + + got_sym = lookup_minimal_symbol ("_GLOBAL_OFFSET_TABLE_", NULL, + symfile_objfile); + if (got_sym.minsym == 0) + { + if (solib_fdpic_debug) + fprintf_unfiltered (gdb_stdlog, + "lm_base: _GLOBAL_OFFSET_TABLE_ not found.\n"); + return 0; + } + + addr = BMSYMBOL_VALUE_ADDRESS (got_sym) + 8; + + if (solib_fdpic_debug) + fprintf_unfiltered (gdb_stdlog, + "lm_base: _GLOBAL_OFFSET_TABLE_ + 8 = %s\n", + hex_string_custom (addr, 8)); + + if (target_read_memory (addr, buf, sizeof buf) != 0) + return 0; + lm_base_cache = extract_unsigned_integer (buf, sizeof buf, byte_order); + + if (solib_fdpic_debug) + fprintf_unfiltered (gdb_stdlog, + "lm_base: lm_base_cache = %s\n", + hex_string_custom (lm_base_cache, 8)); + + return lm_base_cache; +} + + +/* Implement the "current_sos" target_so_ops method. */ + +static struct so_list * +fdpic_current_sos (void) +{ + enum bfd_endian byte_order = gdbarch_byte_order (target_gdbarch ()); + CORE_ADDR lm_addr, mgot; + struct so_list *sos_head = NULL; + struct so_list **sos_next_ptr = &sos_head; + + /* Make sure that the main executable has been relocated. This is + required in order to find the address of the global offset table, + which in turn is used to find the link map info. (See lm_base() + for details.) + + Note that the relocation of the main executable is also performed + by solib_create_inferior_hook(), however, in the case of core + files, this hook is called too late in order to be of benefit to + solib_add. solib_add eventually calls this this function, + fdpic_current_sos, and also precedes the call to + solib_create_inferior_hook(). (See post_create_inferior() in + infcmd.c.) */ + if (main_executable_lm_info == 0 && core_bfd != NULL) + fdpic_relocate_main_executable (); + + /* Fetch the GOT corresponding to the main executable. */ + mgot = main_got (); + + /* Locate the address of the first link map struct. */ + lm_addr = lm_base (); + + /* We have at least one link map entry. Fetch the lot of them, + building the solist chain. */ + while (lm_addr) + { + struct ext_link_map lm_buf; + CORE_ADDR got_addr; + + if (solib_fdpic_debug) + fprintf_unfiltered (gdb_stdlog, + "current_sos: reading link_map entry at %s\n", + hex_string_custom (lm_addr, 8)); + + if (target_read_memory (lm_addr, (gdb_byte *) &lm_buf, + sizeof (lm_buf)) != 0) + { + warning (_("fdpic_current_sos: Unable to read link map entry. " + "Shared object chain may be incomplete.")); + break; + } + + got_addr + = extract_unsigned_integer (lm_buf.l_addr.got_value, + sizeof (lm_buf.l_addr.got_value), + byte_order); + /* If the got_addr is the same as mgotr, then we're looking at the + entry for the main executable. By convention, we don't include + this in the list of shared objects. */ + if (got_addr != mgot) + { + int errcode; + gdb::unique_xmalloc_ptr<char> name_buf; + struct int_elf32_fdpic_loadmap *loadmap; + struct so_list *sop; + CORE_ADDR addr; + + /* Fetch the load map address. */ + addr = extract_unsigned_integer (lm_buf.l_addr.map, + sizeof lm_buf.l_addr.map, + byte_order); + loadmap = fetch_loadmap (addr); + if (loadmap == NULL) + { + warning (_("fdpic_current_sos: Unable to fetch load map. " + "Shared object chain may be incomplete.")); + break; + } + + sop = XCNEW (struct so_list); + lm_info_fdpic *li = new lm_info_fdpic; + sop->lm_info = li; + li->map = loadmap; + li->got_value = got_addr; + li->lm_addr = lm_addr; + /* Fetch the name. */ + addr = extract_unsigned_integer (lm_buf.l_name, + sizeof (lm_buf.l_name), + byte_order); + target_read_string (addr, &name_buf, SO_NAME_MAX_PATH_SIZE - 1, + &errcode); + + if (solib_fdpic_debug) + fprintf_unfiltered (gdb_stdlog, "current_sos: name = %s\n", + name_buf.get ()); + + if (errcode != 0) + warning (_("Can't read pathname for link map entry: %s."), + safe_strerror (errcode)); + else + { + strncpy (sop->so_name, name_buf.get (), + SO_NAME_MAX_PATH_SIZE - 1); + sop->so_name[SO_NAME_MAX_PATH_SIZE - 1] = '\0'; + strcpy (sop->so_original_name, sop->so_name); + } + + *sos_next_ptr = sop; + sos_next_ptr = &sop->next; + } + else + { + main_lm_addr = lm_addr; + } + + lm_addr = extract_unsigned_integer (lm_buf.l_next, + sizeof (lm_buf.l_next), byte_order); + } + + enable_break2 (); + + return sos_head; +} + + +/* Return 1 if PC lies in the dynamic symbol resolution code of the + run time loader. */ + +static CORE_ADDR interp_text_sect_low; +static CORE_ADDR interp_text_sect_high; +static CORE_ADDR interp_plt_sect_low; +static CORE_ADDR interp_plt_sect_high; + +static int +fdpic_in_dynsym_resolve_code (CORE_ADDR pc) +{ + return ((pc >= interp_text_sect_low && pc < interp_text_sect_high) + || (pc >= interp_plt_sect_low && pc < interp_plt_sect_high) + || in_plt_section (pc)); +} + +/* Given a loadmap and an address, return the displacement needed + to relocate the address. */ + +static CORE_ADDR +displacement_from_map (struct int_elf32_fdpic_loadmap *map, + CORE_ADDR addr) +{ + int seg; + + for (seg = 0; seg < map->nsegs; seg++) + { + if (map->segs[seg].p_vaddr <= addr + && addr < map->segs[seg].p_vaddr + map->segs[seg].p_memsz) + { + return map->segs[seg].addr - map->segs[seg].p_vaddr; + } + } + + return 0; +} + +/* Print a warning about being unable to set the dynamic linker + breakpoint. */ + +static void +enable_break_failure_warning (void) +{ + warning (_("Unable to find dynamic linker breakpoint function.\n" + "GDB will be unable to debug shared library initializers\n" + "and track explicitly loaded dynamic code.")); +} + +/* Helper function for gdb_bfd_lookup_symbol. */ + +static int +cmp_name (const asymbol *sym, const void *data) +{ + return (strcmp (sym->name, (const char *) data) == 0); +} + +/* Arrange for dynamic linker to hit breakpoint. + + The dynamic linkers has, as part of its debugger interface, support + for arranging for the inferior to hit a breakpoint after mapping in + the shared libraries. This function enables that breakpoint. + + On the FR-V, using the shared library (FDPIC) ABI, the symbol + _dl_debug_addr points to the r_debug struct which contains + a field called r_brk. r_brk is the address of the function + descriptor upon which a breakpoint must be placed. Being a + function descriptor, we must extract the entry point in order + to set the breakpoint. + + Our strategy will be to get the .interp section from the + executable. This section will provide us with the name of the + interpreter. We'll open the interpreter and then look up + the address of _dl_debug_addr. We then relocate this address + using the interpreter's loadmap. Once the relocated address + is known, we fetch the value (address) corresponding to r_brk + and then use that value to fetch the entry point of the function + we're interested in. */ + +static int enable_break2_done = 0; + +static int +enable_break2 (void) +{ + enum bfd_endian byte_order = gdbarch_byte_order (target_gdbarch ()); + asection *interp_sect; + + if (enable_break2_done) + return 1; + + interp_text_sect_low = interp_text_sect_high = 0; + interp_plt_sect_low = interp_plt_sect_high = 0; + + /* Find the .interp section; if not found, warn the user and drop + into the old breakpoint at symbol code. */ + interp_sect = bfd_get_section_by_name (exec_bfd, ".interp"); + if (interp_sect) + { + unsigned int interp_sect_size; + char *buf; + int status; + CORE_ADDR addr, interp_loadmap_addr; + gdb_byte addr_buf[FDPIC_PTR_SIZE]; + struct int_elf32_fdpic_loadmap *ldm; + + /* Read the contents of the .interp section into a local buffer; + the contents specify the dynamic linker this program uses. */ + interp_sect_size = bfd_section_size (exec_bfd, interp_sect); + buf = (char *) alloca (interp_sect_size); + bfd_get_section_contents (exec_bfd, interp_sect, + buf, 0, interp_sect_size); + + /* Now we need to figure out where the dynamic linker was + loaded so that we can load its symbols and place a breakpoint + in the dynamic linker itself. + + This address is stored on the stack. However, I've been unable + to find any magic formula to find it for Solaris (appears to + be trivial on GNU/Linux). Therefore, we have to try an alternate + mechanism to find the dynamic linker's base address. */ + + gdb_bfd_ref_ptr tmp_bfd; + TRY + { + tmp_bfd = solib_bfd_open (buf); + } + CATCH (ex, RETURN_MASK_ALL) + { + } + END_CATCH + + if (tmp_bfd == NULL) + { + enable_break_failure_warning (); + return 0; + } + + status = fdpic_fdpic_loadmap_addresses (target_gdbarch (), + &interp_loadmap_addr, 0); + if (status < 0) + { + warning (_("Unable to determine dynamic linker loadmap address.")); + enable_break_failure_warning (); + return 0; + } + + if (solib_fdpic_debug) + fprintf_unfiltered (gdb_stdlog, + "enable_break: interp_loadmap_addr = %s\n", + hex_string_custom (interp_loadmap_addr, 8)); + + ldm = fetch_loadmap (interp_loadmap_addr); + if (ldm == NULL) + { + warning (_("Unable to load dynamic linker loadmap at address %s."), + hex_string_custom (interp_loadmap_addr, 8)); + enable_break_failure_warning (); + return 0; + } + + /* Record the relocated start and end address of the dynamic linker + text and plt section for svr4_in_dynsym_resolve_code. */ + interp_sect = bfd_get_section_by_name (tmp_bfd.get (), ".text"); + if (interp_sect) + { + interp_text_sect_low + = bfd_section_vma (tmp_bfd.get (), interp_sect); + interp_text_sect_low + += displacement_from_map (ldm, interp_text_sect_low); + interp_text_sect_high + = interp_text_sect_low + bfd_section_size (tmp_bfd.get (), + interp_sect); + } + interp_sect = bfd_get_section_by_name (tmp_bfd.get (), ".plt"); + if (interp_sect) + { + interp_plt_sect_low = + bfd_section_vma (tmp_bfd.get (), interp_sect); + interp_plt_sect_low + += displacement_from_map (ldm, interp_plt_sect_low); + interp_plt_sect_high = + interp_plt_sect_low + bfd_section_size (tmp_bfd.get (), + interp_sect); + } + + addr = gdb_bfd_lookup_symbol (tmp_bfd.get (), cmp_name, "_dl_debug_addr"); + + if (addr == 0) + { + warning (_("Could not find symbol _dl_debug_addr " + "in dynamic linker")); + enable_break_failure_warning (); + return 0; + } + + if (solib_fdpic_debug) + fprintf_unfiltered (gdb_stdlog, + "enable_break: _dl_debug_addr " + "(prior to relocation) = %s\n", + hex_string_custom (addr, 8)); + + addr += displacement_from_map (ldm, addr); + + if (solib_fdpic_debug) + fprintf_unfiltered (gdb_stdlog, + "enable_break: _dl_debug_addr " + "(after relocation) = %s\n", + hex_string_custom (addr, 8)); + + /* Fetch the address of the r_debug struct. */ + if (target_read_memory (addr, addr_buf, sizeof addr_buf) != 0) + { + warning (_("Unable to fetch contents of _dl_debug_addr " + "(at address %s) from dynamic linker"), + hex_string_custom (addr, 8)); + } + addr = extract_unsigned_integer (addr_buf, sizeof addr_buf, byte_order); + + if (solib_fdpic_debug) + fprintf_unfiltered (gdb_stdlog, + "enable_break: _dl_debug_addr[0..3] = %s\n", + hex_string_custom (addr, 8)); + + /* If it's zero, then the ldso hasn't initialized yet, and so + there are no shared libs yet loaded. */ + if (addr == 0) + { + if (solib_fdpic_debug) + fprintf_unfiltered (gdb_stdlog, + "enable_break: ldso not yet initialized\n"); + /* Do not warn, but mark to run again. */ + return 0; + } + + /* Fetch the r_brk field. It's 8 bytes from the start of + _dl_debug_addr. */ + if (target_read_memory (addr + 8, addr_buf, sizeof addr_buf) != 0) + { + warning (_("Unable to fetch _dl_debug_addr->r_brk " + "(at address %s) from dynamic linker"), + hex_string_custom (addr + 8, 8)); + enable_break_failure_warning (); + return 0; + } + addr = extract_unsigned_integer (addr_buf, sizeof addr_buf, byte_order); + + /* Now fetch the function entry point. */ + if (target_read_memory (addr, addr_buf, sizeof addr_buf) != 0) + { + warning (_("Unable to fetch _dl_debug_addr->.r_brk entry point " + "(at address %s) from dynamic linker"), + hex_string_custom (addr, 8)); + enable_break_failure_warning (); + return 0; + } + addr = extract_unsigned_integer (addr_buf, sizeof addr_buf, byte_order); + + /* We're done with the loadmap. */ + xfree (ldm); + + /* Remove all the solib event breakpoints. Their addresses + may have changed since the last time we ran the program. */ + remove_solib_event_breakpoints (); + + /* Now (finally!) create the solib breakpoint. */ + create_solib_event_breakpoint (target_gdbarch (), addr); + + enable_break2_done = 1; + + return 1; + } + + /* Tell the user we couldn't set a dynamic linker breakpoint. */ + enable_break_failure_warning (); + + /* Failure return. */ + return 0; +} + +static int +enable_break (void) +{ + asection *interp_sect; + CORE_ADDR entry_point; + + if (symfile_objfile == NULL) + { + if (solib_fdpic_debug) + fprintf_unfiltered (gdb_stdlog, + "enable_break: No symbol file found.\n"); + return 0; + } + + if (!entry_point_address_query (&entry_point)) + { + if (solib_fdpic_debug) + fprintf_unfiltered (gdb_stdlog, + "enable_break: Symbol file has no entry point.\n"); + return 0; + } + + /* Check for the presence of a .interp section. If there is no + such section, the executable is statically linked. */ + + interp_sect = bfd_get_section_by_name (exec_bfd, ".interp"); + + if (interp_sect == NULL) + { + if (solib_fdpic_debug) + fprintf_unfiltered (gdb_stdlog, + "enable_break: No .interp section found.\n"); + return 0; + } + + create_solib_event_breakpoint (target_gdbarch (), entry_point); + + if (solib_fdpic_debug) + fprintf_unfiltered (gdb_stdlog, + "enable_break: solib event breakpoint " + "placed at entry point: %s\n", + hex_string_custom (entry_point, 8)); + return 1; +} + +/* CLYON: FIXME */ +int +fdpic_fdpic_loadmap_addresses (struct gdbarch *gdbarch, CORE_ADDR *interp_addr, + CORE_ADDR *exec_addr) +{ +#if 0 + if (frv_abi (gdbarch) != FRV_ABI_FDPIC) + return -1; + else + { +#endif + enum bfd_endian byte_order = gdbarch_byte_order (target_gdbarch ()); + gdb::optional<gdb::byte_vector> buf + = target_read_alloc (current_top_target (), TARGET_OBJECT_FDPIC, "exec"); + /* CHECK BUF CF solib-dsbt.c */ + + if (exec_addr != NULL) + *exec_addr = extract_unsigned_integer (buf->data (), 4 /*FIXME*/, byte_order); + + buf = target_read_alloc (current_top_target (), TARGET_OBJECT_FDPIC, "interp"); + if (interp_addr != NULL) + *interp_addr = extract_unsigned_integer (buf->data (), 4 /*FIXME*/, byte_order); + + return 0; /* FIXME */ +#if 0 + struct regcache *regcache = get_current_regcache (); + + if (interp_addr != NULL) + { + ULONGEST val; + regcache_cooked_read_unsigned (regcache, + fdpic_loadmap_interp_regnum, &val); + *interp_addr = val; + } + if (exec_addr != NULL) + { + ULONGEST val; + regcache_cooked_read_unsigned (regcache, + fdpic_loadmap_exec_regnum, &val); + *exec_addr = val; + } + return 0; +#endif +#if 0 + } +#endif +} + + +#if 0 +/* Per-program-space data key. */ +static const struct program_space_data *solib_fdpic_pspace_data; + +static void +fdpic_pspace_data_cleanup (struct program_space *pspace, void *arg) +{ + xfree (arg); +} + +/* Get the current fdpic data. If none is found yet, add it now. This + function always returns a valid object. */ + +static struct fdpic_info * +get_fdpic_info (void) +{ + struct fdpic_info *info; + + info = (struct fdpic_info *) program_space_data (current_program_space, + solib_fdpic_pspace_data); + if (info != NULL) + return info; + + info = XCNEW (struct fdpic_info); + set_program_space_data (current_program_space, solib_fdpic_pspace_data, info); + + info->lm_base_cache = 0; + info->main_lm_addr = 0; + /* FIXME is_static_binary */ + + return info; +} +/* Interrogate the Linux kernel to find out where the program was loaded. + There are two load maps; one for the executable and one for the + interpreter (only in the case of a dynamically linked executable). */ + +static void +fdpic_get_initial_loadmaps (void) +{ + struct dsbt_info *info = get_dsbt_info (); + gdb::optional<gdb::byte_vector> buf + = target_read_alloc (current_top_target (), TARGET_OBJECT_FDPIC, "exec"); + + if (!buf || buf->empty ()) + { + info->exec_loadmap = NULL; + error (_("Error reading DSBT exec loadmap")); + } + info->exec_loadmap = decode_loadmap (buf->data ()); + if (solib_dsbt_debug) + dsbt_print_loadmap (info->exec_loadmap); + + buf = target_read_alloc (current_top_target (), TARGET_OBJECT_FDPIC, "exec"); + if (!buf || buf->empty ()) + { + info->interp_loadmap = NULL; + error (_("Error reading DSBT interp loadmap")); + } + info->interp_loadmap = decode_loadmap (buf->data ()); + if (solib_dsbt_debug) + dsbt_print_loadmap (info->interp_loadmap); +} +#endif + +static void +fdpic_relocate_main_executable (void) +{ + int status; + CORE_ADDR exec_addr, interp_addr; + struct int_elf32_fdpic_loadmap *ldm; + int changed; + struct obj_section *osect; + + status = fdpic_fdpic_loadmap_addresses (target_gdbarch (), + &interp_addr, &exec_addr); + + if (status < 0 || (exec_addr == 0 && interp_addr == 0)) + { + /* Not using FDPIC ABI, so do nothing. */ + return; + } + + /* Fetch the loadmap located at ``exec_addr''. */ + ldm = fetch_loadmap (exec_addr); + if (ldm == NULL) + error (_("Unable to load the executable's loadmap.")); + + delete main_executable_lm_info; + main_executable_lm_info = new lm_info_fdpic; + main_executable_lm_info->map = ldm; + + gdb::unique_xmalloc_ptr<struct section_offsets> new_offsets + (XCNEWVEC (struct section_offsets, symfile_objfile->num_sections)); + changed = 0; + + ALL_OBJFILE_OSECTIONS (symfile_objfile, osect) + { + CORE_ADDR orig_addr, addr, offset; + int osect_idx; + int seg; + + osect_idx = osect - symfile_objfile->sections; + + /* Current address of section. */ + addr = obj_section_addr (osect); + /* Offset from where this section started. */ + offset = ANOFFSET (symfile_objfile->section_offsets, osect_idx); + /* Original address prior to any past relocations. */ + orig_addr = addr - offset; + + for (seg = 0; seg < ldm->nsegs; seg++) + { + if (ldm->segs[seg].p_vaddr <= orig_addr + && orig_addr < ldm->segs[seg].p_vaddr + ldm->segs[seg].p_memsz) + { + new_offsets->offsets[osect_idx] + = ldm->segs[seg].addr - ldm->segs[seg].p_vaddr; + + if (new_offsets->offsets[osect_idx] != offset) + changed = 1; + break; + } + } + } + + if (changed) + objfile_relocate (symfile_objfile, new_offsets.get ()); + + /* Now that symfile_objfile has been relocated, we can compute the + GOT value and stash it away. */ + main_executable_lm_info->got_value = main_got (); +} + +/* Implement the "create_inferior_hook" target_solib_ops method. + + For the FR-V shared library ABI (FDPIC), the main executable needs + to be relocated. The shared library breakpoints also need to be + enabled. */ + +static void +fdpic_solib_create_inferior_hook (int from_tty) +{ + /* Relocate main executable. */ + fdpic_relocate_main_executable (); + + /* Enable shared library breakpoints. */ + if (!enable_break ()) + { + warning (_("shared library handler failed to enable breakpoint")); + return; + } +} + +static void +fdpic_clear_solib (void) +{ + lm_base_cache = 0; + enable_break2_done = 0; + main_lm_addr = 0; + + delete main_executable_lm_info; + main_executable_lm_info = NULL; +} + +static void +fdpic_free_so (struct so_list *so) +{ + lm_info_fdpic *li = (lm_info_fdpic *) so->lm_info; + + delete li; +} + +static void +fdpic_relocate_section_addresses (struct so_list *so, + struct target_section *sec) +{ + int seg; + lm_info_fdpic *li = (lm_info_fdpic *) so->lm_info; + int_elf32_fdpic_loadmap *map = li->map; + + for (seg = 0; seg < map->nsegs; seg++) + { + if (map->segs[seg].p_vaddr <= sec->addr + && sec->addr < map->segs[seg].p_vaddr + map->segs[seg].p_memsz) + { + CORE_ADDR displ = map->segs[seg].addr - map->segs[seg].p_vaddr; + + sec->addr += displ; + sec->endaddr += displ; + break; + } + } +} + +/* Return the GOT address associated with the main executable. Return + 0 if it can't be found. */ + +static CORE_ADDR +main_got (void) +{ + struct bound_minimal_symbol got_sym; + + got_sym = lookup_minimal_symbol ("_GLOBAL_OFFSET_TABLE_", + NULL, symfile_objfile); + if (got_sym.minsym == 0) + return 0; + + return BMSYMBOL_VALUE_ADDRESS (got_sym); +} + +/* Find the global pointer for the given function address ADDR. */ + +CORE_ADDR +fdpic_fdpic_find_global_pointer (CORE_ADDR addr) +{ + struct so_list *so; + + so = master_so_list (); + while (so) + { + int seg; + lm_info_fdpic *li = (lm_info_fdpic *) so->lm_info; + int_elf32_fdpic_loadmap *map = li->map; + + for (seg = 0; seg < map->nsegs; seg++) + { + if (map->segs[seg].addr <= addr + && addr < map->segs[seg].addr + map->segs[seg].p_memsz) + return li->got_value; + } + + so = so->next; + } + + /* Didn't find it in any of the shared objects. So assume it's in the + main executable. */ + return main_got (); +} + +/* Forward declarations for fdpic_fdpic_find_canonical_descriptor(). */ +static CORE_ADDR find_canonical_descriptor_in_load_object + (CORE_ADDR, CORE_ADDR, const char *, bfd *, lm_info_fdpic *); + +/* Given a function entry point, attempt to find the canonical descriptor + associated with that entry point. Return 0 if no canonical descriptor + could be found. */ + +CORE_ADDR +fdpic_fdpic_find_canonical_descriptor (CORE_ADDR entry_point) +{ + const char *name; + CORE_ADDR addr; + CORE_ADDR got_value; + struct symbol *sym; + + /* Fetch the corresponding global pointer for the entry point. */ + got_value = fdpic_fdpic_find_global_pointer (entry_point); + + /* Attempt to find the name of the function. If the name is available, + it'll be used as an aid in finding matching functions in the dynamic + symbol table. */ + sym = find_pc_function (entry_point); + if (sym == 0) + name = 0; + else + name = SYMBOL_LINKAGE_NAME (sym); + + /* Check the main executable. */ + addr = find_canonical_descriptor_in_load_object + (entry_point, got_value, name, symfile_objfile->obfd, + main_executable_lm_info); + + /* If descriptor not found via main executable, check each load object + in list of shared objects. */ + if (addr == 0) + { + struct so_list *so; + + so = master_so_list (); + while (so) + { + lm_info_fdpic *li = (lm_info_fdpic *) so->lm_info; + + addr = find_canonical_descriptor_in_load_object + (entry_point, got_value, name, so->abfd, li); + + if (addr != 0) + break; + + so = so->next; + } + } + + return addr; +} + +static CORE_ADDR +find_canonical_descriptor_in_load_object + (CORE_ADDR entry_point, CORE_ADDR got_value, const char *name, bfd *abfd, + lm_info_fdpic *lm) +{ + enum bfd_endian byte_order = gdbarch_byte_order (target_gdbarch ()); + arelent *rel; + unsigned int i; + CORE_ADDR addr = 0; + + /* Nothing to do if no bfd. */ + if (abfd == 0) + return 0; + + /* Nothing to do if no link map. */ + if (lm == 0) + return 0; + + /* We want to scan the dynamic relocs for R_FDPIC_FUNCDESC relocations. + (More about this later.) But in order to fetch the relocs, we + need to first fetch the dynamic symbols. These symbols need to + be cached due to the way that bfd_canonicalize_dynamic_reloc() + works. (See the comments in the declaration of struct lm_info + for more information.) */ + if (lm->dyn_syms == NULL) + { + long storage_needed; + unsigned int number_of_symbols; + + /* Determine amount of space needed to hold the dynamic symbol table. */ + storage_needed = bfd_get_dynamic_symtab_upper_bound (abfd); + + /* If there are no dynamic symbols, there's nothing to do. */ + if (storage_needed <= 0) + return 0; + + /* Allocate space for the dynamic symbol table. */ + lm->dyn_syms = (asymbol **) xmalloc (storage_needed); + + /* Fetch the dynamic symbol table. */ + number_of_symbols = bfd_canonicalize_dynamic_symtab (abfd, lm->dyn_syms); + + if (number_of_symbols == 0) + return 0; + } + + /* Fetch the dynamic relocations if not already cached. */ + if (lm->dyn_relocs == NULL) + { + long storage_needed; + + /* Determine amount of space needed to hold the dynamic relocs. */ + storage_needed = bfd_get_dynamic_reloc_upper_bound (abfd); + + /* Bail out if there are no dynamic relocs. */ + if (storage_needed <= 0) + return 0; + + /* Allocate space for the relocs. */ + lm->dyn_relocs = (arelent **) xmalloc (storage_needed); + + /* Fetch the dynamic relocs. */ + lm->dyn_reloc_count + = bfd_canonicalize_dynamic_reloc (abfd, lm->dyn_relocs, lm->dyn_syms); + } + + /* Search the dynamic relocs. */ + for (i = 0; i < lm->dyn_reloc_count; i++) + { + rel = lm->dyn_relocs[i]; + + /* Relocs of interest are those which meet the following + criteria: + + - the names match (assuming the caller could provide + a name which matches ``entry_point''). + - the relocation type must be R_FDPIC_FUNCDESC. Relocs + of this type are used (by the dynamic linker) to + look up the address of a canonical descriptor (allocating + it if need be) and initializing the GOT entry referred + to by the offset to the address of the descriptor. + + These relocs of interest may be used to obtain a + candidate descriptor by first adjusting the reloc's + address according to the link map and then dereferencing + this address (which is a GOT entry) to obtain a descriptor + address. */ + if ((name == 0 || strcmp (name, (*rel->sym_ptr_ptr)->name) == 0) + /*FIXME && rel->howto->type == R_FDPIC_FUNCDESC*/) + { + gdb_byte buf [FDPIC_PTR_SIZE]; + + /* Compute address of address of candidate descriptor. */ + addr = rel->address + displacement_from_map (lm->map, rel->address); + + /* Fetch address of candidate descriptor. */ + if (target_read_memory (addr, buf, sizeof buf) != 0) + continue; + addr = extract_unsigned_integer (buf, sizeof buf, byte_order); + + /* Check for matching entry point. */ + if (target_read_memory (addr, buf, sizeof buf) != 0) + continue; + if (extract_unsigned_integer (buf, sizeof buf, byte_order) + != entry_point) + continue; + + /* Check for matching got value. */ + if (target_read_memory (addr + 4, buf, sizeof buf) != 0) + continue; + if (extract_unsigned_integer (buf, sizeof buf, byte_order) + != got_value) + continue; + + /* Match was successful! Exit loop. */ + break; + } + } + + return addr; +} + +/* Given an objfile, return the address of its link map. This value is + needed for TLS support. */ +CORE_ADDR +fdpic_fetch_objfile_link_map (struct objfile *objfile) +{ + struct so_list *so; + + /* Cause fdpic_current_sos() to be run if it hasn't been already. */ + if (main_lm_addr == 0) + solib_add (0, 0, 1); + + /* fdpic_current_sos() will set main_lm_addr for the main executable. */ + if (objfile == symfile_objfile) + return main_lm_addr; + + /* The other link map addresses may be found by examining the list + of shared libraries. */ + for (so = master_so_list (); so; so = so->next) + { + lm_info_fdpic *li = (lm_info_fdpic *) so->lm_info; + + if (so->objfile == objfile) + return li->lm_addr; + } + + /* Not found! */ + return 0; +} + +struct target_so_ops fdpic_so_ops; + +void +_initialize_fdpic_solib (void) +{ + fdpic_so_ops.relocate_section_addresses = fdpic_relocate_section_addresses; + fdpic_so_ops.free_so = fdpic_free_so; + fdpic_so_ops.clear_solib = fdpic_clear_solib; + fdpic_so_ops.solib_create_inferior_hook = fdpic_solib_create_inferior_hook; + fdpic_so_ops.current_sos = fdpic_current_sos; + fdpic_so_ops.open_symbol_file_object = open_symbol_file_object; + fdpic_so_ops.in_dynsym_resolve_code = fdpic_in_dynsym_resolve_code; + fdpic_so_ops.bfd_open = solib_bfd_open; + + /* Debug this file's internals. */ + add_setshow_zuinteger_cmd ("solib-fdpic", class_maintenance, + &solib_fdpic_debug, _("\ +Set internal debugging of shared library code for FR-V."), _("\ +Show internal debugging of shared library code for FR-V."), _("\ +When non-zero, FR-V solib specific internal debugging is enabled."), + NULL, + NULL, /* FIXME: i18n: */ + &setdebuglist, &showdebuglist); +} |