libc: set up memory partitions

* Newlib now defines a special z_newlib_partition containing
  all globals relevant to newlib. Most of these are in libc.a
  with a heap tracking variable in newlib's hooks.

* Both C libraries now expose a k_mem_partition containing the
  bounds of the malloc heap arena. Threads that want to use
  libc malloc() will need to add this to their memory domain.

* z_newlib_get_heap_bounds has been removed, in favor of the
  memory partition for the heap arena

* ztest now includes the C library partitions in its memory
  domain.

* The mem_alloc test now runs in user mode to prove that this
  all works for both C libraries.

Signed-off-by: Andrew Boie <[email protected]>

Author: Andrew Boie

CMakeLists.txt

@@ -1228,12 +1228,16 @@ if(CONFIG_APP_SHARED_MEM AND CONFIG_USERSPACE)
     kernel ${ZEPHYR_LIBS_PROPERTY}
     )
 
+  if(CONFIG_NEWLIB_LIBC)
+    set(NEWLIB_PART -l libc.a z_newlib_partition)
+  endif()
   add_custom_command(
     TARGET ${APP_SMEM_DEP}
     COMMAND ${PYTHON_EXECUTABLE}
     ${ZEPHYR_BASE}/scripts/gen_app_partitions.py
     -d ${OBJ_FILE_DIR}
     -o ${APP_SMEM_LD}
+    ${NEWLIB_PART}
     $<$<BOOL:${CMAKE_VERBOSE_MAKEFILE}>:--verbose>
     WORKING_DIRECTORY ${PROJECT_BINARY_DIR}/
     COMMENT "Generating app_smem linker section"

include/misc/libc-hooks.h

@@ -27,16 +27,27 @@ __syscall int _zephyr_read(char *buf, int nbytes);
 
 __syscall int _zephyr_write(const void *buf, int nbytes);
 
+#ifdef CONFIG_APP_SHARED_MEM
+/* Memory partition containing newlib's globals. This includes all the globals
+ * within libc.a and the supporting zephyr hooks, but not the malloc arena.
+ */
+extern struct k_mem_partition z_newlib_partition;
+#endif /* CONFIG_APP_SHARED_MEM */
+
 #else
 /* Minimal libc */
 
 __syscall int _zephyr_fputc(int c, FILE *stream);
 
 __syscall size_t _zephyr_fwrite(const void *_MLIBC_RESTRICT ptr, size_t size,
 				size_t nitems, FILE *_MLIBC_RESTRICT stream);
-
 #endif /* CONFIG_NEWLIB_LIBC */
 
+#ifdef CONFIG_APP_SHARED_MEM
+/* Memory partition containing the libc malloc arena */
+extern struct k_mem_partition z_malloc_partition;
+#endif
+
 #include <syscalls/libc-hooks.h>
 
 #endif /* ZEPHYR_INCLUDE_MISC_LIBC_HOOKS_H_ */

kernel/include/kernel_internal.h

@@ -206,21 +206,6 @@ extern void smp_init(void);
 
 extern void smp_timer_init(void);
 
-#ifdef CONFIG_NEWLIB_LIBC
-/**
- * @brief Fetch dimentions of newlib heap area for _sbrk()
- *
- * This memory region is used for heap allocations by the newlib C library.
- * If user threads need to have access to this, the results returned can be
- * used to program memory protection hardware appropriately.
- *
- * @param base Pointer to void pointer, filled in with the heap starting
- *             address
- * @param size Pointer to a size_y, filled in with the maximum heap size
- */
-extern void z_newlib_get_heap_bounds(void **base, size_t *size);
-#endif
-
 extern u32_t z_early_boot_rand32_get(void);
 
 #if CONFIG_STACK_POINTER_RANDOM

lib/libc/minimal/source/stdlib/malloc.c

@@ -10,15 +10,26 @@
 #include <errno.h>
 #include <misc/mempool.h>
 #include <string.h>
+#include <app_memory/app_memdomain.h>
 
 #define LOG_LEVEL CONFIG_KERNEL_LOG_LEVEL
 #include <logging/log.h>
 LOG_MODULE_DECLARE(os);
 
+#ifdef CONFIG_APP_SHARED_MEM
+K_APPMEM_PARTITION_DEFINE(z_malloc_partition);
+#endif
+
 #if (CONFIG_MINIMAL_LIBC_MALLOC_ARENA_SIZE > 0)
+#ifdef CONFIG_APP_SHARED_MEM
+#define POOL_SECTION K_APP_DMEM_SECTION(z_malloc_partition)
+#else
+#define POOL_SECTION .data
+#endif /* CONFIG_APP_SHARED_MEM */
+
 K_MUTEX_DEFINE(malloc_mutex);
 SYS_MEM_POOL_DEFINE(z_malloc_mem_pool, &malloc_mutex, 16,
-		    CONFIG_MINIMAL_LIBC_MALLOC_ARENA_SIZE, 1, 4, .data);
+		    CONFIG_MINIMAL_LIBC_MALLOC_ARENA_SIZE, 1, 4, POOL_SECTION);
 
 void *malloc(size_t size)
 {

lib/libc/newlib/libc-hooks.c

@@ -14,12 +14,30 @@
 #include <misc/errno_private.h>
 #include <misc/libc-hooks.h>
 #include <syscall_handler.h>
+#include <app_memory/app_memdomain.h>
+#include <init.h>
+
+#ifdef CONFIG_APP_SHARED_MEM
+K_APPMEM_PARTITION_DEFINE(z_newlib_partition);
+#define LIBC_BSS	K_APP_BMEM(z_newlib_partition)
+#define LIBC_DATA	K_APP_DMEM(z_newlib_partition)
+
+#if CONFIG_NEWLIB_LIBC_ALIGNED_HEAP_SIZE
+K_APPMEM_PARTITION_DEFINE(z_malloc_partition);
+#define MALLOC_BSS	K_APP_BMEM(z_malloc_partition)
+#endif /* CONFIG_NEWLIB_LIBC_ALIGNED_HEAP_SIZE */
+
+#else
+#define LIBC_BSS
+#define LIBC_DATA
+#define MALLOC_BSS
+#endif /* CONFIG_APP_SHARED_MEM */
 
 #define USED_RAM_END_ADDR   POINTER_TO_UINT(&_end)
 
 #if CONFIG_NEWLIB_LIBC_ALIGNED_HEAP_SIZE
 /* Compiler will throw an error if the provided value isn't a power of two */
-static unsigned char __kernel __aligned(CONFIG_NEWLIB_LIBC_ALIGNED_HEAP_SIZE)
+MALLOC_BSS static unsigned char __kernel __aligned(CONFIG_NEWLIB_LIBC_ALIGNED_HEAP_SIZE)
 	heap_base[CONFIG_NEWLIB_LIBC_ALIGNED_HEAP_SIZE];
 #define MAX_HEAP_SIZE CONFIG_NEWLIB_LIBC_ALIGNED_HEAP_SIZE
 #else
@@ -48,9 +66,25 @@ extern void *_heap_sentry;
 #endif
 
 static unsigned char *heap_base = UINT_TO_POINTER(USED_RAM_END_ADDR);
+
+#ifdef CONFIG_APP_SHARED_MEM
+struct k_mem_partition z_malloc_partition;
+
+static int malloc_prepare(struct device *unused)
+{
+	ARG_UNUSED(unused);
+
+	z_malloc_partition.start = (u32_t)heap_base;
+	z_malloc_partition.size = MAX_HEAP_SIZE;
+	z_malloc_partition.attr = K_MEM_PARTITION_P_RW_U_RW;
+	return 0;
+}
+
+SYS_INIT(malloc_prepare, APPLICATION, CONFIG_KERNEL_INIT_PRIORITY_DEFAULT);
+#endif
 #endif /* CONFIG_NEWLIB_LIBC_ALIGNED_HEAP_SIZE */
 
-static unsigned int heap_sz;
+LIBC_BSS static unsigned int heap_sz;
 
 static int _stdout_hook_default(int c)
 {
@@ -207,12 +241,6 @@ void *_sbrk(int count)
 }
 FUNC_ALIAS(_sbrk, sbrk, void *);
 
-void z_newlib_get_heap_bounds(void **base, size_t *size)
-{
-	*base = heap_base;
-	*size = MAX_HEAP_SIZE;
-}
-
 int *__errno(void)
 {
 	return z_errno();

tests/lib/mem_alloc/prj_newlib.conf

@@ -1,3 +1,4 @@
 CONFIG_ZTEST=y
 CONFIG_NEWLIB_LIBC=y
 CONFIG_MAIN_STACK_SIZE=1024
+CONFIG_NEWLIB_LIBC_ALIGNED_HEAP_SIZE=512

tests/lib/mem_alloc/src/main.c

@@ -24,10 +24,6 @@
 
 #define BUF_LEN 10
 
-#ifdef CONFIG_MINIMAL_LIBC_MALLOC_ARENA_SIZE
-#define MAX_HEAP_SIZE CONFIG_MINIMAL_LIBC_MALLOC_ARENA_SIZE
-#endif
-
 /**
  * @brief Test dynamic memory allocation using malloc
  *
@@ -40,6 +36,7 @@ void test_malloc(void)
 
 	iptr = malloc(BUF_LEN * sizeof(int));
 	zassert_not_null((iptr), "malloc failed, errno: %d", errno);
+	memset(iptr, 'p', BUF_LEN * sizeof(int));
 	free(iptr);
 	iptr = NULL;
 }
@@ -64,7 +61,7 @@ void test_free(void)
  * @see calloc(), free()
  */
 #define CALLOC_BUFLEN (200)
-static unsigned char zerobuf[CALLOC_BUFLEN];
+ZTEST_BMEM static unsigned char zerobuf[CALLOC_BUFLEN];
 
 void test_calloc(void)
 {
@@ -74,6 +71,7 @@ void test_calloc(void)
 	zassert_not_null((cptr), "calloc failed, errno: %d", errno);
 	zassert_true(((memcmp(cptr, zerobuf, CALLOC_BUFLEN)) == 0),
 			"calloc failed to set zero value, errno: %d", errno);
+	memset(cptr, 'p', CALLOC_BUFLEN);
 	free(cptr);
 	cptr = NULL;
 }
@@ -83,7 +81,7 @@ void test_calloc(void)
  *
  * @see malloc(), realloc(), free()
  */
-unsigned char filled_buf[BUF_LEN];
+ZTEST_BMEM unsigned char filled_buf[BUF_LEN];
 
 void test_realloc(void)
 {
@@ -191,17 +189,9 @@ void test_memalloc_all(void)
 
 void test_memalloc_max(void)
 {
-	size_t max_heap_size = 0;
 	char *ptr = NULL;
 
-#ifdef CONFIG_NEWLIB_LIBC
-	void *heap_base = NULL;
-
-	z_newlib_get_heap_bounds(&heap_base, &max_heap_size);
-#else
-	max_heap_size = MAX_HEAP_SIZE;
-#endif
-	ptr = malloc(max_heap_size + 1);
+	ptr = malloc(0xF0000000);
 	zassert_is_null(ptr, "malloc passed unexpectedly");
 	free(ptr);
 	ptr = NULL;
@@ -210,13 +200,13 @@ void test_memalloc_max(void)
 void test_main(void)
 {
 	ztest_test_suite(test_c_lib_dynamic_memalloc,
-			 ztest_unit_test(test_malloc),
-			 ztest_unit_test(test_free),
-			 ztest_unit_test(test_calloc),
-			 ztest_unit_test(test_realloc),
-			 ztest_unit_test(test_reallocarray),
-			 ztest_unit_test(test_memalloc_all),
-			 ztest_unit_test(test_memalloc_max)
+			 ztest_user_unit_test(test_malloc),
+			 ztest_user_unit_test(test_free),
+			 ztest_user_unit_test(test_calloc),
+			 ztest_user_unit_test(test_realloc),
+			 ztest_user_unit_test(test_reallocarray),
+			 ztest_user_unit_test(test_memalloc_all),
+			 ztest_user_unit_test(test_memalloc_max)
 			 );
 	ztest_run_test_suite(test_c_lib_dynamic_memalloc);
 }

tests/lib/mem_alloc/testcase.yaml

@@ -2,9 +2,9 @@ tests:
   libraries.libc.minimal:
     extra_args: CONF_FILE=prj.conf
     arch_exclude: posix
-    tags: clib minimal_libc
+    tags: clib minimal_libc userspace
   libraries.libc.newlib:
     extra_args: CONF_FILE=prj_newlib.conf
     arch_exclude: posix
     filter: TOOLCHAIN_HAS_NEWLIB == 1
-    tags: clib newlib
+    tags: clib newlib userspace

tests/ztest/src/ztest.c

@@ -7,6 +7,10 @@
 #include <ztest.h>
 #include <stdio.h>
 #include <app_memory/app_memdomain.h>
+#ifdef CONFIG_APP_SHARED_MEM
+#include <misc/libc-hooks.h>
+#endif
+
 #ifdef KERNEL
 __kernel static struct k_thread ztest_thread;
 #endif
@@ -297,7 +301,13 @@ void main(void)
 {
 #ifdef CONFIG_APP_SHARED_MEM
 	struct k_mem_partition *parts[] = {
-		&ztest_mem_partition
+		&ztest_mem_partition,
+#ifdef CONFIG_NEWLIB_LIBC
+		/* Newlib libc.a library and hooks globals */
+		&z_newlib_partition,
+#endif
+		/* Both minimal and newlib libc expose this for malloc arena */
+		&z_malloc_partition
 	};
 
 	/* Ztests just have one memory domain with one partition.