diff options
Diffstat (limited to 'runtime/transport')
| -rw-r--r-- | runtime/transport/symbols.c | 571 | ||||
| -rw-r--r-- | runtime/transport/transport.c | 18 |
2 files changed, 22 insertions, 567 deletions
diff --git a/runtime/transport/symbols.c b/runtime/transport/symbols.c index 77263284..c868c5fd 100644 --- a/runtime/transport/symbols.c +++ b/runtime/transport/symbols.c @@ -16,205 +16,20 @@ #define _STP_SYMBOLS_C_ #include "../sym.h" -static char *_stp_symbol_data = NULL; -static int _stp_symbol_state = 0; -static char *_stp_module_data = NULL; -static int _stp_module_state = 0; -/* these are all the symbol types we are interested in */ -static int _stp_sym_type_ok(int type) -{ - /* we only care about function symbols, which are in the text section */ - if (type == 'T' || type == 't') - return 1; - return 0; -} - -/* From a module struct, scan the symtab and figure out how much space */ -/* we need to store all the parts we are interested in */ -static unsigned _stp_get_sym_sizes(struct module *m, unsigned *dsize) -{ - unsigned int i; - unsigned num = 0, datasize = 0; - for (i = 0; i < m->num_symtab; i++) { - char *str = (char *)(m->strtab + m->symtab[i].st_name); - if (*str != '\0' && _stp_sym_type_ok(m->symtab[i].st_info)) { - datasize += strlen(str) + 1; - num++; - } - } - *dsize = datasize; - return num; -} - -/* allocate space for a module, sections, and symbols */ -static struct _stp_module *_stp_alloc_module(unsigned sectsize, unsigned num, unsigned datasize) -{ - struct _stp_module *mod = (struct _stp_module *)_stp_kzalloc(sizeof(struct _stp_module)); - if (mod == NULL) - goto bad; - - mod->sections = (struct _stp_symbol *)_stp_kmalloc(sectsize); - if (mod->sections == NULL) - goto bad; - - mod->symbols = (struct _stp_symbol *)_stp_kmalloc(num * sizeof(struct _stp_symbol)); - if (mod->symbols == NULL) { - mod->symbols = (struct _stp_symbol *)_stp_vmalloc(num * sizeof(struct _stp_symbol)); - if (mod->symbols == NULL) - goto bad; - mod->allocated.symbols = 1; - } - - mod->symbol_data = _stp_kmalloc(datasize); - if (mod->symbol_data == NULL) { - mod->symbol_data = _stp_vmalloc(datasize); - if (mod->symbol_data == NULL) - goto bad; - mod->allocated.symbol_data = 1; - } - - mod->num_symbols = num; - return mod; - -bad: - if (mod) { - if (mod->sections) - _stp_kfree(mod->sections); - if (mod->symbols) { - if (mod->allocated.symbols) - _stp_vfree(mod->symbols); - else - _stp_kfree(mod->symbols); - } - _stp_kfree(mod); - } - return NULL; -} - -static void _stp_free_module(struct _stp_module *mod) -{ - /* The module write lock is held. Any prior readers of this */ - /* module's data will have read locks and need to finish before */ - /* the memory is freed. */ - write_lock(&mod->lock); - write_unlock(&mod->lock); /* there will be no more readers */ - - /* Free symbol memory */ - /* If symbol_data wasn't allocated, then symbols weren't either. */ - if (mod->symbol_data) { - if (mod->symbols) { - if (mod->allocated.symbols) - _stp_vfree(mod->symbols); - else - _stp_kfree(mod->symbols); - } - if (mod->allocated.symbol_data) - _stp_vfree(mod->symbol_data); - else - _stp_kfree(mod->symbol_data); - } - if (mod->unwind_data) { - if (mod->allocated.unwind_data) - _stp_vfree(mod->unwind_data); - else - _stp_kfree(mod->unwind_data); - } - if (mod->unwind_hdr) { - if (mod->allocated.unwind_hdr) - _stp_vfree(mod->unwind_hdr); - else - _stp_kfree(mod->unwind_hdr); - } - if (mod->sections) - _stp_kfree(mod->sections); - - /* free module memory */ - _stp_kfree(mod); -} - -/* Delete a module and free its memory. */ -/* The module lock should already be held before calling this. */ -static void _stp_del_module(struct _stp_module *mod) -{ - int i, num; - - dbug_sym(1, "deleting module %s\n", mod->name); - - /* signal relocation code to clear its cache */ - _stp_module_relocate((char *)-1, NULL, 0); - - /* remove module from the arrays */ - for (num = 0; num < _stp_num_modules; num++) { - if (_stp_modules[num] == mod) - break; - } - if (num >= _stp_num_modules) - return; - for (i = num; i < _stp_num_modules - 1; i++) - _stp_modules[i] = _stp_modules[i + 1]; - - for (num = 0; num < _stp_num_modules; num++) { - if (_stp_modules_by_addr[num] == mod) - break; - } - for (i = num; i < _stp_num_modules - 1; i++) - _stp_modules_by_addr[i] = _stp_modules_by_addr[i + 1]; - - _stp_num_modules--; - - _stp_free_module(mod); -} - -static void _stp_free_modules(void) -{ - int i; - /* This only happens when the systemtap module unloads */ - /* so there is no need for locks. */ - for (i = _stp_num_modules - 1; i >= 0; i--) - _stp_del_module(_stp_modules[i]); -} - -static unsigned long _stp_kallsyms_lookup_name(const char *name); static void _stp_create_unwind_hdr(struct _stp_module *m); -extern unsigned _stp_num_kernel_symbols; -extern struct _stp_symbol _stp_kernel_symbols[]; - -/* initialize the kernel symbols */ -static int _stp_init_kernel_symbols(void) -{ - _stp_modules[0] = (struct _stp_module *)_stp_kzalloc(sizeof(struct _stp_module)); - if (_stp_modules[0] == NULL) { - _dbug("cannot allocate memory\n"); - return -1; - } - _stp_modules[0]->symbols = _stp_kernel_symbols; - _stp_modules[0]->num_symbols = _stp_num_kernel_symbols; - rwlock_init(&_stp_modules[0]->lock); - _stp_num_modules = 1; - - /* Note: this mapping is used by kernel/_stext pseudo-relocations. */ - _stp_modules[0]->text = 0; /* This should be set by a STP_RELOCATE message. */ - _stp_modules[0]->data = 0; /* XXX */ - _stp_modules[0]->text_size = 0; /* XXX */ - - _stp_kretprobe_trampoline = 0; /* XXX */ - _stp_modules_by_addr[0] = _stp_modules[0]; - - dbug_sym(2, "systemtap supplied %u kernel symbols\n", _stp_num_kernel_symbols); - - return 0; -} - static void _stp_do_relocation(const char __user *buf, size_t count) { struct _stp_msg_relocation msg; + unsigned mi, si; + if (sizeof(msg) != count) { - errk ("STP_RELOCATE message size mismatch (%u vs %u)\n", sizeof(msg), count); + errk ("STP_RELOCATE message size mismatch (%lu vs %lu)\n", + (long unsigned) sizeof(msg), (long unsigned) count); return; } @@ -223,107 +38,28 @@ static void _stp_do_relocation(const char __user *buf, size_t count) dbug_sym(2, "relocate (%s %s 0x%lx)\n", msg.module, msg.reloc, (unsigned long) msg.address); - if (!strcmp (msg.module, "kernel") && - !strcmp (msg.reloc, "_stext")) - - { - unsigned i; - - _stp_modules[0]->text = (unsigned long) msg.address; - /* Now, relocate all the elements in the kernel symbol table. - We should at that point arrive at a strict subset of the - /proc/kallsyms table. */ + /* Save the relocation value. XXX: While keeping the data here is + fine for the kernel address space ("kernel" and "*.ko" modules), + it is NOT fine for user-space apps. They need a separate + relocation values for each address space, since the same shared + libraries/executables can be mapped in at different + addresses. */ - for (i=0; i<_stp_modules[0]->num_symbols; i++) - _stp_modules[0]->symbols[i].addr += msg.address; - } -} - - -#if 0 -static void _stp_do_unwind_data(const char __user *buf, size_t count) -{ - u32 unwind_len; - unsigned long flags; - char name[STP_MODULE_NAME_LEN]; - int i; - struct _stp_module *m; - - dbug_unwind(1, "got unwind data, count=%d\n", count); - - if (count < STP_MODULE_NAME_LEN + sizeof(unwind_len)) { - dbug_unwind(1, "unwind message too short\n"); - return; - } - if (strncpy_from_user(name, buf, STP_MODULE_NAME_LEN) < 0) { - errk("userspace copy failed\n"); - return; - } - dbug_unwind(1, "name=%s\n", name); - if (!strcmp(name,"*")) { - /* OK, all initial unwind data received. Ready to go. */ - _stp_ctl_send(STP_TRANSPORT, NULL, 0); - return; - } - count -= STP_MODULE_NAME_LEN; - buf += STP_MODULE_NAME_LEN; - - if (get_user(unwind_len, (u32 __user *)buf)) { - errk("userspace copy failed\n"); - return; - } - count -= sizeof(unwind_len); - buf += sizeof(unwind_len); - if (count != unwind_len) { - dbug_unwind(1, "count=%d unwind_len=%d\n", (int)count, (int)unwind_len); - return; - } + for (mi=0; mi<_stp_num_modules; mi++) + { + if (strcmp (_stp_modules[mi]->name, msg.module)) + continue; - STP_RLOCK_MODULES; - for (i = 0; i < _stp_num_modules; i++) { - if (strcmp(name, _stp_modules[i]->name) == 0) - break; - } - if (unlikely(i == _stp_num_modules)) { - dbug_unwind(1, "module %s not found!\n", name); - STP_RUNLOCK_MODULES; - return; - } - m = _stp_modules[i]; - write_lock(&m->lock); - STP_RUNLOCK_MODULES; + for (si=0; si<_stp_modules[mi]->num_sections; si++) + { + if (strcmp (_stp_modules[mi]->sections[si].symbol, msg.reloc)) + continue; - /* allocate space for unwind data */ - m->unwind_data = _stp_kmalloc(count); - if (unlikely(m->unwind_data == NULL)) { - m->unwind_data = _stp_vmalloc(count); - if (m->unwind_data == NULL) { - errk("kmalloc failed\n"); - goto done; - } - m->allocated.unwind_data = 1; - } - - if (unlikely(copy_from_user(m->unwind_data, buf, count))) { - errk("userspace copy failed\n"); - if (m->unwind_data) { - if (m->allocated.unwind_data) - _stp_vfree(m->unwind_data); - else - _stp_kfree(m->unwind_data); - m->unwind_data = NULL; - } - goto done; - } - m->unwind_data_len = count; -#ifdef STP_USE_DWARF_UNWINDER - _stp_create_unwind_hdr(m); -#endif -done: - write_unlock(&m->lock); + _stp_modules[mi]->sections[si].addr = msg.address; + } /* loop over sections */ + } /* loop over modules */ } -#endif /* do_unwind_data; not used */ static int _stp_compare_addr(const void *p1, const void *p2) @@ -428,270 +164,5 @@ static int _stp_section_is_interesting(const char *name) return ret; } -#if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,25) -struct module_sect_attr -{ - struct module_attribute mattr; - char *name; - unsigned long address; -}; - -struct module_sect_attrs -{ - struct attribute_group grp; - unsigned int nsections; - struct module_sect_attr attrs[0]; -}; -#endif - -/* Create a new _stp_module and load the symbols */ -static struct _stp_module *_stp_load_module_symbols(struct module *mod) -{ - int i, num, overflow = 0; - struct module_sect_attrs *sa = mod->sect_attrs; - struct attribute_group *sag = & sa->grp; - unsigned sect_size = 0, sect_num = 0, sym_size, sym_num; - struct _stp_module *sm; - char *dataptr, *endptr; - unsigned nsections = 0; - -#ifdef STAPCONF_MODULE_NSECTIONS - nsections = sa->nsections; -#else - /* count section attributes on older kernel */ - struct attribute** gattr; - for (gattr = sag->attrs; *gattr; gattr++) - nsections++; - dbug_sym(2, "\tcount %d\n", nsections); -#endif - - /* calculate how much space to allocate for section strings */ - for (i = 0; i < nsections; i++) { - if (_stp_section_is_interesting(sa->attrs[i].name)) { - sect_num++; - sect_size += strlen(sa->attrs[i].name) + 1; - dbug_sym(2, "\t%s\t%lx\n", sa->attrs[i].name, sa->attrs[i].address); - } - } - sect_size += sect_num * sizeof(struct _stp_symbol); - - /* and how much space for symbols */ - sym_num = _stp_get_sym_sizes(mod, &sym_size); - - sm = _stp_alloc_module(sect_size, sym_num, sym_size); - if (!sm) { - errk("failed to allocate memory for module.\n"); - return NULL; - } - - strlcpy(sm->name, mod->name, STP_MODULE_NAME_LEN); - sm->module = (unsigned long)mod; - sm->text = (unsigned long)mod->module_core; - sm->text_size = mod->core_text_size; - sm->data = 0; /* fixme */ - sm->num_sections = sect_num; - rwlock_init(&sm->lock); - - /* copy in section data */ - dataptr = (char *)((long)sm->sections + sect_num * sizeof(struct _stp_symbol)); - endptr = (char *)((long)sm->sections + sect_size); - num = 0; - for (i = 0; i < nsections; i++) { - size_t len, maxlen; - if (_stp_section_is_interesting(sa->attrs[i].name)) { - sm->sections[num].addr = sa->attrs[i].address; - sm->sections[num].symbol = dataptr; - maxlen = (size_t) (endptr - dataptr); - len = strlcpy(dataptr, sa->attrs[i].name, maxlen); - if (unlikely(len >= maxlen)) { - _dbug("dataptr=%lx endptr=%lx len=%d maxlen=%d\n", dataptr, endptr, len, maxlen); - overflow = 1; - } - dataptr += len + 1; - num++; - } - } - if (unlikely(overflow)) { - errk("Section names truncated!!! Should never happen!!\n"); - *endptr = 0; - overflow = 0; - } - - /* now copy all the symbols we are interested in */ - dataptr = sm->symbol_data; - endptr = dataptr + sym_size - 1; - num = 0; - for (i = 0; i < mod->num_symtab; i++) { - char *str = (char *)(mod->strtab + mod->symtab[i].st_name); - if (*str != '\0' && _stp_sym_type_ok(mod->symtab[i].st_info)) { - sm->symbols[num].symbol = dataptr; - sm->symbols[num].addr = mod->symtab[i].st_value; - while (*str && (dataptr < endptr)) - *dataptr++ = *str++; - if (unlikely(*str)) - overflow = 1; - *dataptr++ = 0; - num++; - } - } - if (unlikely(overflow)) - errk("Symbol names truncated!!! Should never happen!!\n"); - - /* sort symbols by address */ - _stp_sort(sm->symbols, num, sizeof(struct _stp_symbol), _stp_compare_addr, _stp_swap_symbol); - - return sm; -} - -/* Remove any old module info from our database. */ -static void _stp_module_exists_delete(struct _stp_module *mod) -{ - int i, num; - /* remove any old modules with the same name */ - for (num = 1; num < _stp_num_modules; num++) { - if (strcmp(_stp_modules[num]->name, mod->name) == 0) { - dbug_sym(1, "found existing module with name %s. Deleting.\n", mod->name); - _stp_del_module(_stp_modules[num]); - break; - } - } - - /* remove modules with overlapping addresses */ - for (num = 1; num < _stp_num_modules; num++) { - if (mod->text + mod->text_size < _stp_modules_by_addr[num]->text) - continue; - if (mod->text < _stp_modules_by_addr[num]->text + _stp_modules_by_addr[num]->text_size) { - dbug_sym(1, "New module %s overlaps with old module %s. Deleting old.\n", - mod->name, _stp_modules_by_addr[num]->name); - _stp_del_module(_stp_modules_by_addr[num]); - } - } - -} - -static void _stp_ins_module(struct module *mod) -{ - int i, num, res; - unsigned long flags; - struct _stp_module *m; - dbug_sym(1, "insert %s\n", mod->name); - m = _stp_load_module_symbols(mod); - if (m == NULL) - return; - - STP_WLOCK_MODULES; - _stp_module_exists_delete(m); - /* check for overflow */ - if (_stp_num_modules == STP_MAX_MODULES) { - errk("Exceeded the limit of %d modules\n", STP_MAX_MODULES); - goto done; - } - - /* insert alphabetically in _stp_modules[] */ - for (num = 1; num < _stp_num_modules; num++) - if (strcmp(_stp_modules[num]->name, m->name) > 0) - break; - for (i = _stp_num_modules; i > num; i--) - _stp_modules[i] = _stp_modules[i - 1]; - _stp_modules[num] = m; - /* insert by text address in _stp_modules_by_addr[] */ - for (num = 1; num < _stp_num_modules; num++) - if (m->text < _stp_modules_by_addr[num]->text) - break; - for (i = _stp_num_modules; i > num; i--) - _stp_modules_by_addr[i] = _stp_modules_by_addr[i - 1]; - _stp_modules_by_addr[num] = m; - _stp_num_modules++; -done: - STP_WUNLOCK_MODULES; - return; -} - -static int _stp_module_load_notify(struct notifier_block *self, unsigned long val, void *data) -{ - struct module *mod = (struct module *)data; - struct _stp_module rmod; - switch (val) { - case MODULE_STATE_COMING: - dbug_sym(1, "module %s load notify\n", mod->name); - _stp_ins_module(mod); - break; - default: - errk("module loaded? val=%ld\n", val); - } - return 0; -} - -static struct notifier_block _stp_module_load_nb = { - .notifier_call = _stp_module_load_notify, -}; - -#include <linux/seq_file.h> - -static int _stp_init_modules(void) -{ - loff_t pos = 0; - void *res; - struct module *mod; - const struct seq_operations *modules_op = (const struct seq_operations *)_stp_kallsyms_lookup_name("modules_op"); - - if (modules_op == NULL) { - _dbug("Lookup of modules_op failed.\n"); - return -1; - } - - /* Use the seq_file interface to safely get a list of installed modules */ - res = modules_op->start(NULL, &pos); - while (res) { - mod = list_entry(res, struct module, list); - _stp_ins_module(mod); - res = modules_op->next(NULL, res, &pos); - } - - if (register_module_notifier(&_stp_module_load_nb)) - errk("failed to load module notifier\n"); - - /* unlocks the list */ - modules_op->stop(NULL, NULL); - -#if 0 /* def STP_USE_DWARF_UNWINDER */ - /* now that we have all the modules, ask for their unwind info */ - { - unsigned long flags; - int i, left = STP_CTL_BUFFER_SIZE; - char buf[STP_CTL_BUFFER_SIZE]; - char *ptr = buf; - *ptr = 0; - - STP_RLOCK_MODULES; - /* Loop through modules, sending module names packed into */ - /* messages of size STP_CTL_BUFFER. */ - for (i = 0; i < _stp_num_modules; i++) { - char *name = _stp_modules[i]->name; - int len = strlen(name); - if (len >= left) { - _stp_ctl_send(STP_UNWIND, buf, sizeof(buf) - left); - ptr = buf; - left = STP_CTL_BUFFER_SIZE; - } - strlcpy(ptr, name, left); - ptr += len + 1; - left -= len + 1; - } - STP_RUNLOCK_MODULES; - - /* Send terminator. When we get this back from stapio */ - /* that means all the unwind info has been sent. */ - strlcpy(ptr, "*", left); - left -= 2; - _stp_ctl_send(STP_UNWIND, buf, sizeof(buf) - left); - } -#else - /* done with modules, now go */ - _stp_ctl_send(STP_TRANSPORT, NULL, 0); -#endif /* STP_USE_DWARF_UNWINDER */ - - return 0; -} #endif /* _STP_SYMBOLS_C_ */ diff --git a/runtime/transport/transport.c b/runtime/transport/transport.c index c6ca4c62..01a24033 100644 --- a/runtime/transport/transport.c +++ b/runtime/transport/transport.c @@ -84,7 +84,6 @@ static void _stp_cleanup_and_exit(int send_exit) int failures; _stp_exit_flag = 1; - unregister_module_notifier(&_stp_module_load_nb); /* we only want to do this stuff once */ _stp_exit_called = 1; @@ -180,8 +179,7 @@ void _stp_transport_close() _stp_unregister_ctl_channel(); if (_stp_utt) utt_trace_remove(_stp_utt); - _stp_free_modules(); - _stp_kill_time(); + _stp_kill_time(); /* Go to a beach. Drink a beer. */ _stp_print_cleanup(); /* free print buffers */ _stp_mem_debug_done(); dbug_trans(1, "---- CLOSED ----\n"); @@ -263,25 +261,11 @@ int _stp_transport_init(void) _stp_transport_state = 1; - dbug_trans(1, "calling init_kernel_symbols\n"); - if (_stp_init_kernel_symbols() < 0) - goto err4; - - /* - dbug_trans(1, "calling init_modules\n"); - if (_stp_init_modules() < 0) - goto err4; - */ - /* Signal stapio to send us STP_START back (XXX: ?!?!?!). */ _stp_ctl_send(STP_TRANSPORT, NULL, 0); return 0; -err4: - errk("failed to initialize modules\n"); - _stp_free_modules(); - destroy_workqueue(_stp_wq); err3: _stp_print_cleanup(); err2: |