Changeset f356618 in mainline for uspace/lib/c/generic/rtld/rtld.c

Timestamp:

2016-05-22T21:05:55Z (9 years ago)

Author:

Jiri Svoboda <jiri@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

b3364b7c

Parents:

af2254ec (diff), 3a9414e (diff)
Note: this is a merge changeset, the changes displayed below correspond to the merge itself.
Use the (diff) links above to see all the changes relative to each parent.

Message:

Merge dynamic linking support for thread local storage.

File:

• uspace/lib/c/generic/rtld/rtld.c (modified) (7 diffs)

uspace/lib/c/generic/rtld/rtld.c

@@ -43 +43 @@
 rtld_t *runtime_env;
 static rtld_t rt_env_static;
-static module_t prog_mod;
 
 /** Initialize the runtime linker for use in a statically-linked executable. */
-void rtld_init_static(void)
-{
+int rtld_init_static(void)
+{
+        int rc;
+
         runtime_env = &rt_env_static;
         list_initialize(&runtime_env->modules);
+        list_initialize(&runtime_env->imodules);
         runtime_env->next_bias = 0x2000000;
         runtime_env->program = NULL;
+        runtime_env->next_id = 1;
+
+        rc = module_create_static_exec(runtime_env, NULL);
+        if (rc != EOK)
+                return rc;
+
+        modules_process_tls(runtime_env);
+
+        return EOK;
 }
 
@@ -62 +73 @@
 {
         rtld_t *env;
+        module_t *prog;
 
         DPRINTF("Load dynamically linked program.\n");
@@ -70 +82 @@
                 return ENOMEM;
 
+        env->next_id = 1;
+
+        prog = calloc(1, sizeof(module_t));
+        if (prog == NULL) {
+                free(env);
+                return ENOMEM;
+        }
+
         /*
          * First we need to process dynamic sections of the executable
@@ -76 +96 @@
 
         DPRINTF("Parse program .dynamic section at %p\n", p_info->dynamic);
-        dynamic_parse(p_info->dynamic, 0, &prog_mod.dyn);
-        prog_mod.bias = 0;
-        prog_mod.dyn.soname = "[program]";
-        prog_mod.rtld = env;
-        prog_mod.exec = true;
-        prog_mod.local = false;
+        dynamic_parse(p_info->dynamic, 0, &prog->dyn);
+        prog->bias = 0;
+        prog->dyn.soname = "[program]";
+        prog->rtld = env;
+        prog->id = rtld_get_next_id(env);
+        prog->exec = true;
+        prog->local = false;
+
+        prog->tdata = p_info->tls.tdata;
+        prog->tdata_size = p_info->tls.tdata_size;
+        prog->tbss_size = p_info->tls.tbss_size;
+        prog->tls_align = p_info->tls.tls_align;
+
+        DPRINTF("prog tdata at %p size %zu, tbss size %zu\n",
+            prog->tdata, prog->tdata_size, prog->tbss_size);
 
         /* Initialize list of loaded modules */
         list_initialize(&env->modules);
-        list_append(&prog_mod.modules_link, &env->modules);
+        list_initialize(&env->imodules);
+        list_append(&prog->modules_link, &env->modules);
 
         /* Pointer to program module. Used as root of the module graph. */
-        env->program = &prog_mod;
+        env->program = prog;
 
         /* Work around non-existent memory space allocation. */
@@ -98 +128 @@
 
         DPRINTF("Load all program dependencies\n");
-        module_load_deps(&prog_mod, 0);
+        module_load_deps(prog, 0);
+
+        /* Compute static TLS size */
+        modules_process_tls(env);
 
         /*
@@ -106 +139 @@
         /* Process relocations in all modules */
         DPRINTF("Relocate all modules\n");
-        modules_process_relocs(env, &prog_mod);
+        modules_process_relocs(env, prog);
 
         *rre = env;
@@ -112 +145 @@
 }
 
+/** Create TLS (Thread Local Storage) data structures.
+ *
+ * @return Pointer to TCB.
+ */
+tcb_t *rtld_tls_make(rtld_t *rtld)
+{
+        void *data;
+        tcb_t *tcb;
+        size_t offset;
+        void **dtv;
+        size_t nmods;
+        size_t i;
+
+        tcb = tls_alloc_arch(&data, rtld->tls_size);
+        if (tcb == NULL)
+                return NULL;
+
+        /** Allocate dynamic thread vector */
+        nmods = list_count(&rtld->imodules);
+        dtv = malloc((nmods + 1) * sizeof(void *));
+        if (dtv == NULL) {
+                tls_free(tcb);
+                return NULL;
+        }
+
+        /*
+         * We define generation number to be equal to vector length.
+         * We start with a vector covering the initially loaded modules.
+         */
+        DTV_GN(dtv) = nmods;
+
+        /*
+         * Copy thread local data from the initialization images of initial
+         * modules. Zero out thread-local uninitialized data.
+         */
+
+#ifdef CONFIG_TLS_VARIANT_1
+        /*
+         * Ascending addresses
+         */
+        offset = 0; i = 1;
+        list_foreach(rtld->imodules, imodules_link, module_t, m) {
+                assert(i == m->id);
+                assert(offset + m->tdata_size + m->tbss_size <= rtld->tls_size);
+                dtv[i++] = data + offset;
+                memcpy(data + offset, m->tdata, m->tdata_size);
+                offset += m->tdata_size;
+                memset(data + offset, 0, m->tbss_size);
+                offset += m->tbss_size;
+        }
+#else /* CONFIG_TLS_VARIANT_2 */
+        /*
+         * Descending addresses
+         */
+        offset = 0; i = 1;
+        list_foreach(rtld->imodules, imodules_link, module_t, m) {
+                assert(i == m->id);
+                assert(offset + m->tdata_size + m->tbss_size <= rtld->tls_size);
+                offset += m->tbss_size;
+                memset(data + rtld->tls_size - offset, 0, m->tbss_size);
+                offset += m->tdata_size;
+                memcpy(data + rtld->tls_size - offset, m->tdata, m->tdata_size);
+                dtv[i++] = data + rtld->tls_size - offset;
+        }
+#endif
+
+        tcb->dtv = dtv;
+        return tcb;
+}
+
+unsigned long rtld_get_next_id(rtld_t *rtld)
+{
+        return rtld->next_id++;
+}
+
+/** Get address of thread-local variable.
+ *
+ * @param rtld RTLD instance
+ * @param tcb TCB of the thread whose instance to return
+ * @param mod_id Module ID
+ * @param offset Offset within TLS block of the module
+ *
+ * @return Address of thread-local variable
+ */
+void *rtld_tls_get_addr(rtld_t *rtld, tcb_t *tcb, unsigned long mod_id,
+    unsigned long offset)
+{
+        module_t *m;
+        size_t dtv_len;
+        void *tls_block;
+
+        dtv_len = DTV_GN(tcb->dtv);
+        if (dtv_len < mod_id) {
+                /* Vector is short */
+
+                tcb->dtv = realloc(tcb->dtv, (1 + mod_id) * sizeof(void *));
+                /* XXX This can fail if OOM */
+                assert(tcb->dtv != NULL);
+                /* Zero out new part of vector */
+                memset(tcb->dtv + (1 + dtv_len), 0, (mod_id - dtv_len) *
+                    sizeof(void *));
+        }
+
+        if (tcb->dtv[mod_id] == NULL) {
+                /* TLS block is not allocated */
+
+                m = module_by_id(rtld, mod_id);
+                assert(m != NULL);
+                /* Should not be initial module, those have TLS pre-allocated */
+                assert(!link_used(&m->imodules_link));
+
+                tls_block = malloc(m->tdata_size + m->tbss_size);
+                /* XXX This can fail if OOM */
+                assert(tls_block != NULL);
+
+                /* Copy tdata */
+                memcpy(tls_block, m->tdata, m->tdata_size);
+                /* Zero out tbss */
+                memset(tls_block + m->tdata_size, 0, m->tbss_size);
+
+                tcb->dtv[mod_id] = tls_block;
+        }
+
+        return (uint8_t *)(tcb->dtv[mod_id]) + offset;
+}
+
 /** @}
  */