aot loader: Refine os_mmap related code (#3711)

Author: wenyongh

core/iwasm/aot/aot_loader.c

@@ -294,6 +294,39 @@ loader_malloc(uint64 size, char *error_buf, uint32 error_buf_size)
     return mem;
 }
 
+static void *
+loader_mmap(uint32 size, bool prot_exec, char *error_buf, uint32 error_buf_size)
+{
+    int map_prot =
+        MMAP_PROT_READ | MMAP_PROT_WRITE | (prot_exec ? MMAP_PROT_EXEC : 0);
+    int map_flags;
+    void *mem;
+
+#if UINTPTR_MAX == UINT64_MAX
+    /* The mmapped AOT data and code in 64-bit targets had better be in
+       range 0 to 2G, or aot loader may fail to apply some relocations,
+       e.g., R_X86_64_32/R_X86_64_32S/R_X86_64_PC32/R_RISCV_32.
+       We try to mmap with MMAP_MAP_32BIT flag first, and if fails, mmap
+       again without the flag. */
+    map_flags = MMAP_MAP_32BIT;
+    if ((mem = os_mmap(NULL, size, map_prot, map_flags,
+                       os_get_invalid_handle()))) {
+        /* The mmapped memory must be in the first 2 Gigabytes of the
+           process address space */
+        bh_assert((uintptr_t)mem < INT32_MAX);
+        return mem;
+    }
+#endif
+
+    map_flags = MMAP_MAP_NONE;
+    if (!(mem = os_mmap(NULL, size, map_prot, map_flags,
+                        os_get_invalid_handle()))) {
+        set_error_buf(error_buf, error_buf_size, "allocate memory failed");
+        return NULL;
+    }
+    return mem;
+}
+
 static char *
 load_string(uint8 **p_buf, const uint8 *buf_end, AOTModule *module,
             bool is_load_from_file_buf,
@@ -2407,7 +2440,8 @@ load_object_data_sections(const uint8 **p_buf, const uint8 *buf_end,
         read_string(buf, buf_end, data_sections[i].name);
         read_uint32(buf, buf_end, data_sections[i].size);
         CHECK_BUF(buf, buf_end, data_sections[i].size);
-        /* temporary record data ptr for merge, will be replaced after mmaped */
+        /* Temporary record data ptr for merge, will be replaced after the
+           merged_data_sections is mmapped */
         if (data_sections[i].size > 0)
             data_sections[i].data = (uint8 *)buf;
         buf += data_sections[i].size;
@@ -2418,33 +2452,13 @@ load_object_data_sections(const uint8 **p_buf, const uint8 *buf_end,
         return false;
     }
     if (total_size > 0) {
-        int map_prot = MMAP_PROT_READ | MMAP_PROT_WRITE;
-#if defined(BUILD_TARGET_X86_64) || defined(BUILD_TARGET_AMD_64) \
-    || defined(BUILD_TARGET_RISCV64_LP64D)                       \
-    || defined(BUILD_TARGET_RISCV64_LP64)
-        /* aot code and data in x86_64 must be in range 0 to 2G due to
-           relocation for R_X86_64_32/32S/PC32 */
-        int map_flags = MMAP_MAP_32BIT;
-#else
-        int map_flags = MMAP_MAP_NONE;
-#endif
         /* Allocate memory for data */
         merged_sections = module->merged_data_sections =
-            os_mmap(NULL, (uint32)total_size, map_prot, map_flags,
-                    os_get_invalid_handle());
+            loader_mmap((uint32)total_size, false, error_buf, error_buf_size);
         if (!merged_sections) {
-            set_error_buf(error_buf, error_buf_size, "allocate memory failed");
             return false;
         }
         module->merged_data_sections_size = (uint32)total_size;
-#if defined(BUILD_TARGET_X86_64) || defined(BUILD_TARGET_AMD_64)
-#if !defined(BH_PLATFORM_LINUX_SGX) && !defined(BH_PLATFORM_WINDOWS) \
-    && !defined(BH_PLATFORM_DARWIN)
-        /* address must be in the first 2 Gigabytes of
-           the process address space */
-        bh_assert((uintptr_t)merged_sections < INT32_MAX);
-#endif
-#endif
     }
 
     /* Second iteration: Create each data section */
@@ -2570,71 +2584,63 @@ try_merge_data_and_text(const uint8 **buf, const uint8 **buf_end,
         return true;
     }
 
-    /* calc total memory needed */
+    /* calculate the total memory needed */
     total_size += align_uint64((uint64)code_size, page_size);
     for (i = 0; i < module->data_section_count; ++i) {
         total_size +=
             align_uint64((uint64)module->data_sections[i].size, page_size);
     }
-    /* distance between .data and .text should not greater than 4GB for some
-     * targets (eg. arm64 reloc need < 4G distance) */
+    /* distance between .data and .text should not be greater than 4GB
+       for some targets (e.g. arm64 reloc need < 4G distance) */
     if (total_size > UINT32_MAX) {
         return false;
     }
+    /* code_size was checked and must be larger than 0 here */
+    bh_assert(total_size > 0);
 
-    if (total_size != 0) {
-        int map_prot = MMAP_PROT_READ | MMAP_PROT_WRITE;
+    sections = loader_mmap((uint32)total_size, false, NULL, 0);
+    if (!sections) {
+        /* merge failed but may be not critical for some targets */
+        return false;
+    }
+    /* change the code part to be executable */
+    if (os_mprotect(sections, code_size,
+                    MMAP_PROT_READ | MMAP_PROT_WRITE | MMAP_PROT_EXEC)
+        != 0) {
+        os_munmap(sections, (uint32)total_size);
+        return false;
+    }
 
-#if defined(BUILD_TARGET_X86_64) || defined(BUILD_TARGET_AMD_64) \
-    || defined(BUILD_TARGET_RISCV64_LP64D)                       \
-    || defined(BUILD_TARGET_RISCV64_LP64)
-        /* aot code and data in x86_64 must be in range 0 to 2G due
-           to relocation for R_X86_64_32/32S/PC32 */
-        int map_flags = MMAP_MAP_32BIT;
-#else
-        int map_flags = MMAP_MAP_NONE;
-#endif
+    module->merged_data_text_sections = sections;
+    module->merged_data_text_sections_size = (uint32)total_size;
 
-        sections = os_mmap(NULL, (uint32)total_size, map_prot, map_flags,
-                           os_get_invalid_handle());
-        if (!sections) {
-            /* merge failed but maybe not critical for some targes */
-            return false;
-        }
-        if (os_mprotect(sections, code_size, map_prot | MMAP_PROT_EXEC) != 0) {
-            os_munmap(sections, (uint32)total_size);
-            return false;
-        }
+    /* order not essential just as compiler does: .text section first */
+    *buf = sections;
+    *buf_end = sections + code_size;
+    bh_memcpy_s(sections, code_size, old_buf, code_size);
+    os_munmap(old_buf, code_size);
+    sections += align_uint((uint32)code_size, page_size);
 
-        module->merged_data_text_sections = sections;
-        module->merged_data_text_sections_size = (uint32)total_size;
-
-        /* order not essential just as compilers do: .text section first */
-        *buf = sections;
-        *buf_end = sections + code_size;
-        bh_memcpy_s(sections, code_size, old_buf, code_size);
-        os_munmap(old_buf, code_size);
-        sections += align_uint((uint32)code_size, page_size);
-
-        /* then .data sections */
-        for (i = 0; i < module->data_section_count; ++i) {
-            AOTObjectDataSection *data_section = module->data_sections + i;
-            uint8 *old_data = data_section->data;
-            data_section->data = sections;
-            bh_memcpy_s(data_section->data, data_section->size, old_data,
-                        data_section->size);
-            sections += align_uint(data_section->size, page_size);
-        }
-        if (module->merged_data_sections) {
-            os_munmap(module->merged_data_sections,
-                      module->merged_data_sections_size);
-            module->merged_data_sections = NULL;
-            module->merged_data_sections_size = 0;
-        }
+    /* then migrate .data sections */
+    for (i = 0; i < module->data_section_count; ++i) {
+        AOTObjectDataSection *data_section = module->data_sections + i;
+        uint8 *old_data = data_section->data;
+        data_section->data = sections;
+        bh_memcpy_s(data_section->data, data_section->size, old_data,
+                    data_section->size);
+        sections += align_uint(data_section->size, page_size);
+    }
+    /* free the original data sections */
+    if (module->merged_data_sections) {
+        os_munmap(module->merged_data_sections,
+                  module->merged_data_sections_size);
+        module->merged_data_sections = NULL;
+        module->merged_data_sections_size = 0;
     }
+
     return true;
 }
-#endif //! defined(BH_PLATFORM_NUTTX) && !defined(BH_PLATFORM_ESP_IDF)
+#endif /* ! defined(BH_PLATFORM_NUTTX) && !defined(BH_PLATFORM_ESP_IDF) */
 
 static bool
 load_text_section(const uint8 *buf, const uint8 *buf_end, AOTModule *module,
@@ -3495,16 +3501,9 @@ load_relocation_section(const uint8 *buf, const uint8 *buf_end,
            + sizeof(uint64) * module->real_plt_count
            + sizeof(uint32) * module->float_plt_count;
     if (size > 0) {
-        map_prot = MMAP_PROT_READ | MMAP_PROT_WRITE | MMAP_PROT_EXEC;
-        /* aot code and data in x86_64 must be in range 0 to 2G due to
-           relocation for R_X86_64_32/32S/PC32 */
-        map_flags = MMAP_MAP_32BIT;
-
         if (size > UINT32_MAX
-            || !(module->extra_plt_data =
-                     os_mmap(NULL, (uint32)size, map_prot, map_flags,
-                             os_get_invalid_handle()))) {
-            set_error_buf(error_buf, error_buf_size, "mmap memory failed");
+            || !(module->extra_plt_data = loader_mmap(
+                     (uint32)size, true, error_buf, error_buf_size))) {
             goto fail;
         }
         module->extra_plt_data_size = (uint32)size;
@@ -3616,19 +3615,12 @@ load_relocation_section(const uint8 *buf, const uint8 *buf_end,
         GOTItem *got_item = module->got_item_list;
         uint32 got_item_idx = 0;
 
-        map_prot = MMAP_PROT_READ | MMAP_PROT_WRITE;
-        /* aot code and data in x86_64 must be in range 0 to 2G due to
-           relocation for R_X86_64_32/32S/PC32 */
-        map_flags = MMAP_MAP_32BIT;
-
         /* Create the GOT for func_ptrs, note that it is different from
            the .got section of a dynamic object file */
         size = (uint64)sizeof(void *) * got_item_count;
         if (size > UINT32_MAX
-            || !(module->got_func_ptrs =
-                     os_mmap(NULL, (uint32)size, map_prot, map_flags,
-                             os_get_invalid_handle()))) {
-            set_error_buf(error_buf, error_buf_size, "mmap memory failed");
+            || !(module->got_func_ptrs = loader_mmap(
+                     (uint32)size, false, error_buf, error_buf_size))) {
             goto fail;
         }
 
@@ -3863,7 +3855,7 @@ load_from_sections(AOTModule *module, AOTSection *sections,
                     if (!try_merge_data_and_text(&buf, &buf_end, module,
                                                  error_buf, error_buf_size))
                         LOG_WARNING("merge .data and .text sections failed");
-#endif //! defined(BH_PLATFORM_NUTTX) && !defined(BH_PLATFORM_ESP_IDF)
+#endif /* ! defined(BH_PLATFORM_NUTTX) && !defined(BH_PLATFORM_ESP_IDF) */
                 if (!load_text_section(buf, buf_end, module, error_buf,
                                        error_buf_size))
                     return false;
@@ -4180,37 +4172,16 @@ create_sections(AOTModule *module, const uint8 *buf, uint32 size,
 
             if (section_type == AOT_SECTION_TYPE_TEXT) {
                 if ((section_size > 0) && !module->is_indirect_mode) {
-                    int map_prot =
-                        MMAP_PROT_READ | MMAP_PROT_WRITE | MMAP_PROT_EXEC;
-#if defined(BUILD_TARGET_X86_64) || defined(BUILD_TARGET_AMD_64) \
-    || defined(BUILD_TARGET_RISCV64_LP64D)                       \
-    || defined(BUILD_TARGET_RISCV64_LP64)
-                    /* aot code and data in x86_64 must be in range 0 to 2G due
-                       to relocation for R_X86_64_32/32S/PC32 */
-                    int map_flags = MMAP_MAP_32BIT;
-#else
-                    int map_flags = MMAP_MAP_NONE;
-#endif
                     total_size =
                         (uint64)section_size + aot_get_plt_table_size();
                     total_size = (total_size + 3) & ~((uint64)3);
                     if (total_size >= UINT32_MAX
                         || !(aot_text =
-                                 os_mmap(NULL, (uint32)total_size, map_prot,
-                                         map_flags, os_get_invalid_handle()))) {
+                                 loader_mmap((uint32)total_size, true,
+                                             error_buf, error_buf_size))) {
                         wasm_runtime_free(section);
-                        set_error_buf(error_buf, error_buf_size,
-                                      "mmap memory failed");
                         goto fail;
                     }
-#if defined(BUILD_TARGET_X86_64) || defined(BUILD_TARGET_AMD_64)
-#if !defined(BH_PLATFORM_LINUX_SGX) && !defined(BH_PLATFORM_WINDOWS) \
-    && !defined(BH_PLATFORM_DARWIN)
-                    /* address must be in the first 2 Gigabytes of
-                       the process address space */
-                    bh_assert((uintptr_t)aot_text < INT32_MAX);
-#endif
-#endif
 
 #if (WASM_MEM_DUAL_BUS_MIRROR != 0)
                     mirrored_text = os_get_dbus_mirror(aot_text);