[feature] add memalign function for areas

This patch provides aligned allocations for all areas. Simple tests
included.

Note that I haven't tested if it conflicts with arena-wide alignements.

src/aml.h

@@ -126,6 +126,8 @@ int aml_vector_destroy(struct aml_vector *vector);
 /* If passed as a flag to arena's mallocx()/reallocx() routines, the newly
  * allocated memory will be 0-initialized. */
 #define AML_ARENA_FLAG_ZERO ((int)0x40)
+/* As a flag to arena mallocx/reallocx, will align on (1<<a). */
+#define AML_ARENA_FLAG_ALIGN(a) ((int)(a))
 
 /* opaque handle to configuration data */
 struct aml_arena_data;
@@ -271,6 +273,7 @@ struct aml_area_ops {
 	void *(*malloc)(struct aml_area_data *area, size_t size);
 	void (*free)(struct aml_area_data *area, void *ptr);
 	void *(*calloc)(struct aml_area_data *area, size_t num, size_t size);
+	void *(*memalign)(struct aml_area_data *area, size_t align, size_t size);
 	void *(*realloc)(struct aml_area_data *area, void *ptr, size_t size);
 	void *(*acquire)(struct aml_area_data *area, size_t size);
 	void (*release)(struct aml_area_data *area, void *ptr);
@@ -711,6 +714,14 @@ void aml_area_free(struct aml_area *area, void *ptr);
  * Returns a pointer to the newly allocated memory buffer; NULL if unsuccessful.
  */
 void *aml_area_calloc(struct aml_area *area, size_t num, size_t size);
+/*
+ * Allocates a new, aligned, memory buffer from a memory area.
+ * "area": an initialized memory area structure.
+ * "align": an alignment for the returned pointer.
+ * "size": the buffer size in bytes; if 0 is passed, NULL will be returned.
+ * Returns a pointer to the newly allocated memory buffer; NULL if unsuccessful.
+ */
+void *aml_area_memalign(struct aml_area *area, size_t align, size_t size);
 /*
  * Changes the size of a previously allocated memory buffer.
  * "area": an initialized memory area structure.

src/area.c

@@ -25,6 +25,12 @@ void *aml_area_calloc(struct aml_area *area, size_t num, size_t size)
 	return area->ops->calloc(area->data, num, size);
 }
 
+void *aml_area_memalign(struct aml_area *area, size_t align, size_t size)
+{
+	assert(area != NULL);
+	return area->ops->memalign(area->data, align, size);
+}
+
 void *aml_area_realloc(struct aml_area *area, void *ptr, size_t size)
 {
 	assert(area != NULL);

src/area_linux.c

@@ -72,6 +72,25 @@ void *aml_area_linux_calloc(struct aml_area_data *a, size_t num, size_t size)
 	return aml_area_linux_malloc(a, num*size);
 }
 
+void *aml_area_linux_memalign(struct aml_area_data *a, size_t align,
+			      size_t size)
+{
+	assert(a != NULL);
+	struct aml_area_linux *area = (struct aml_area_linux *)a;
+	struct aml_arena *arena = (struct aml_arena *)
+		area->ops.manager.get_arena(&area->data.manager);
+	void *ret;
+	assert(arena != NULL);
+	if(size == 0)
+		return NULL;
+
+	area->ops.mbind.pre_bind(&area->data.mbind);
+	ret = aml_arena_mallocx(arena, size, AML_ARENA_FLAG_ZERO |
+				AML_ARENA_FLAG_ALIGN(align));
+	area->ops.mbind.post_bind(&area->data.mbind, ret, size);
+	return ret;
+}
+
 void *aml_area_linux_realloc(struct aml_area_data *a, void *ptr, size_t size)
 {
 	assert(a != NULL);
@@ -121,6 +140,7 @@ struct aml_area_ops aml_area_linux_ops = {
 	aml_area_linux_malloc,
 	aml_area_linux_free,
 	aml_area_linux_calloc,
+	aml_area_linux_memalign,
 	aml_area_linux_realloc,
 	aml_area_linux_acquire,
 	aml_area_linux_release,

src/area_posix.c

@@ -57,6 +57,13 @@ void *aml_area_posix_calloc(struct aml_area_data *data, size_t nm, size_t size)
 	return calloc(nm, size);
 }
 
+void *aml_area_posix_memalign(struct aml_area_data *data, size_t align,
+			      size_t size)
+{
+	assert(data != NULL);
+	return aligned_alloc(align, size);
+}
+
 void *aml_area_posix_realloc(struct aml_area_data *data, void *ptr, size_t size)
 {
 	assert(data != NULL);
@@ -79,6 +86,7 @@ struct aml_area_ops aml_area_posix_ops = {
 	aml_area_posix_malloc,
 	aml_area_posix_free,
 	aml_area_posix_calloc,
+	aml_area_posix_memalign,
 	aml_area_posix_realloc,
 	aml_area_posix_acquire,
 	aml_area_posix_release,

tests/area_linux.c

@@ -7,6 +7,7 @@ void doit(struct aml_area *area)
 {
 	void *ptr;
 	unsigned long *a, *b, *c;
+	intptr_t iptr;
 
 	/* try to allocate something */
 	ptr = aml_area_malloc(area, sizeof(unsigned long) * 10);
@@ -30,6 +31,14 @@ void doit(struct aml_area *area)
 	assert(a[0] == a[9]);
 	aml_area_free(area, ptr);
 
+	/* memalign */
+	ptr = aml_area_memalign(area, 16, sizeof(unsigned long));
+	assert(ptr != NULL);
+	iptr = ptr;
+	assert(iptr % 16 == 0);
+	aml_area_free(area, ptr);
+
+
 	/* libc API compatibility: calloc(0): same as malloc(0) */
 	ptr = aml_area_calloc(area, 0, sizeof(unsigned long));
 	aml_area_free(area, ptr);

tests/area_posix.c

@@ -7,6 +7,7 @@ int main(int argc, char *argv[])
 	void *ptr;
 	unsigned long *a, *b, *c;
 	unsigned long i;
+	intptr_t iptr;
 
 	/* library initialization */
 	aml_init(&argc, &argv);
@@ -36,6 +37,13 @@ int main(int argc, char *argv[])
 	assert(a[0] == a[9]);
 	aml_area_free(&area, ptr);
 
+	/* memalign */
+	ptr = aml_area_memalign(&area, 16, sizeof(unsigned long));
+	assert(ptr != NULL);
+	iptr = ptr;
+	assert(iptr % 16 == 0);
+	aml_area_free(&area, ptr);
+
 	/* libc API compatibility: calloc(0): same as malloc(0) */
 	ptr = aml_area_calloc(&area, 0, sizeof(unsigned long));
 	aml_area_free(&area, ptr);