genalloc:support memory-allocation with bytes-alignment to genalloc

Bytes alignment is required to manage some special RAM,
so add gen_pool_first_fit_align to genalloc,
meanwhile add gen_pool_alloc_algo to pass algo in case user
layer using more than one algo, and pass data to
gen_pool_first_fit_align(modify gen_pool_alloc as a wrapper)

Signed-off-by: Zhao Qiang <qiang.zhao@freescale.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>
diff --git a/lib/genalloc.c b/lib/genalloc.c
index 116a166..b8cf89d 100644
--- a/lib/genalloc.c
+++ b/lib/genalloc.c
@@ -270,6 +270,25 @@
  */
 unsigned long gen_pool_alloc(struct gen_pool *pool, size_t size)
 {
+	return gen_pool_alloc_algo(pool, size, pool->algo, pool->data);
+}
+EXPORT_SYMBOL(gen_pool_alloc);
+
+/**
+ * gen_pool_alloc_algo - allocate special memory from the pool
+ * @pool: pool to allocate from
+ * @size: number of bytes to allocate from the pool
+ * @algo: algorithm passed from caller
+ * @data: data passed to algorithm
+ *
+ * Allocate the requested number of bytes from the specified pool.
+ * Uses the pool allocation function (with first-fit algorithm by default).
+ * Can not be used in NMI handler on architectures without
+ * NMI-safe cmpxchg implementation.
+ */
+unsigned long gen_pool_alloc_algo(struct gen_pool *pool, size_t size,
+		genpool_algo_t algo, void *data)
+{
 	struct gen_pool_chunk *chunk;
 	unsigned long addr = 0;
 	int order = pool->min_alloc_order;
@@ -290,8 +309,8 @@
 
 		end_bit = chunk_size(chunk) >> order;
 retry:
-		start_bit = pool->algo(chunk->bits, end_bit, start_bit, nbits,
-				pool->data);
+		start_bit = algo(chunk->bits, end_bit, start_bit,
+				 nbits, data, pool);
 		if (start_bit >= end_bit)
 			continue;
 		remain = bitmap_set_ll(chunk->bits, start_bit, nbits);
@@ -310,7 +329,7 @@
 	rcu_read_unlock();
 	return addr;
 }
-EXPORT_SYMBOL(gen_pool_alloc);
+EXPORT_SYMBOL(gen_pool_alloc_algo);
 
 /**
  * gen_pool_dma_alloc - allocate special memory from the pool for DMA usage
@@ -501,15 +520,42 @@
  * @start: The bitnumber to start searching at
  * @nr: The number of zeroed bits we're looking for
  * @data: additional data - unused
+ * @pool: pool to find the fit region memory from
  */
 unsigned long gen_pool_first_fit(unsigned long *map, unsigned long size,
-		unsigned long start, unsigned int nr, void *data)
+		unsigned long start, unsigned int nr, void *data,
+		struct gen_pool *pool)
 {
 	return bitmap_find_next_zero_area(map, size, start, nr, 0);
 }
 EXPORT_SYMBOL(gen_pool_first_fit);
 
 /**
+ * gen_pool_first_fit_align - find the first available region
+ * of memory matching the size requirement (alignment constraint)
+ * @map: The address to base the search on
+ * @size: The bitmap size in bits
+ * @start: The bitnumber to start searching at
+ * @nr: The number of zeroed bits we're looking for
+ * @data: data for alignment
+ * @pool: pool to get order from
+ */
+unsigned long gen_pool_first_fit_align(unsigned long *map, unsigned long size,
+		unsigned long start, unsigned int nr, void *data,
+		struct gen_pool *pool)
+{
+	struct genpool_data_align *alignment;
+	unsigned long align_mask;
+	int order;
+
+	alignment = data;
+	order = pool->min_alloc_order;
+	align_mask = ((alignment->align + (1UL << order) - 1) >> order) - 1;
+	return bitmap_find_next_zero_area(map, size, start, nr, align_mask);
+}
+EXPORT_SYMBOL(gen_pool_first_fit_align);
+
+/**
  * gen_pool_first_fit_order_align - find the first available region
  * of memory matching the size requirement. The region will be aligned
  * to the order of the size specified.
@@ -518,10 +564,11 @@
  * @start: The bitnumber to start searching at
  * @nr: The number of zeroed bits we're looking for
  * @data: additional data - unused
+ * @pool: pool to find the fit region memory from
  */
 unsigned long gen_pool_first_fit_order_align(unsigned long *map,
 		unsigned long size, unsigned long start,
-		unsigned int nr, void *data)
+		unsigned int nr, void *data, struct gen_pool *pool)
 {
 	unsigned long align_mask = roundup_pow_of_two(nr) - 1;
 
@@ -537,12 +584,14 @@
  * @start: The bitnumber to start searching at
  * @nr: The number of zeroed bits we're looking for
  * @data: additional data - unused
+ * @pool: pool to find the fit region memory from
  *
  * Iterate over the bitmap to find the smallest free region
  * which we can allocate the memory.
  */
 unsigned long gen_pool_best_fit(unsigned long *map, unsigned long size,
-		unsigned long start, unsigned int nr, void *data)
+		unsigned long start, unsigned int nr, void *data,
+		struct gen_pool *pool)
 {
 	unsigned long start_bit = size;
 	unsigned long len = size + 1;