[PATCH v10 1/5] genalloc:support memory-allocation with bytes-alignment to genalloc

Zhao Qiang
2015-09-18T07:21:26Z

Bytes alignment is required to manage some special RAM,
so add gen_pool_first_fit_align to genalloc,
meanwhile add gen_pool_alloc_data to pass data to
gen_pool_first_fit_align(modify gen_pool_alloc as a wrapper)

Signed-off-by: Zhao Qiang <qiang.zhao@freescale.com>
---
Changes for v6:
- patches set v6 include a new patch because of using
- genalloc to manage QE MURAM, patch 0001 is the new
- patch, adding bytes alignment for allocation for use.
Changes for v7:
- cpm muram also need to use genalloc to manage, it has
a function to reserve a specific region of muram,
add offset to genpool_data for start addr to be allocated.
Changes for v8:
- remove supporting reserving a specific region from this patch
add a new patch to support it.
Changes for v9:
- Nil
Changes for v10:
- Nil

include/linux/genalloc.h | 24 ++++++++++++++++----
lib/genalloc.c | 58 +++++++++++++++++++++++++++++++++++++++++++-----
2 files changed, 73 insertions(+), 9 deletions(-)

diff --git a/include/linux/genalloc.h b/include/linux/genalloc.h
index 1ccaab4..aaf3dc2 100644
--- a/include/linux/genalloc.h
+++ b/include/linux/genalloc.h
@@ -30,10 +30,12 @@
#ifndef __GENALLOC_H__
#define __GENALLOC_H__

+#include <linux/types.h>
#include <linux/spinlock_types.h>

struct device;
struct device_node;
+struct gen_pool;

/**
* Allocation callback function type definition
@@ -47,7 +49,7 @@ typedef unsigned long (*genpool_algo_t)(unsigned long *map,
unsigned long size,
unsigned long start,
unsigned int nr,
- void *data);
+ void *data, struct gen_pool *pool);

/*
* General purpose special memory pool descriptor.
@@ -73,6 +75,13 @@ struct gen_pool_chunk {
unsigned long bits[0]; /* bitmap for allocating memory chunk */
};

+/*
+ * gen_pool data descriptor for gen_pool_first_fit_align.
+ */
+struct genpool_data_align {
+ int align; /* alignment by bytes for starting address */
+};
+
extern struct gen_pool *gen_pool_create(int, int);
extern phys_addr_t gen_pool_virt_to_phys(struct gen_pool *pool, unsigned long);
extern int gen_pool_add_virt(struct gen_pool *, unsigned long, phys_addr_t,
@@ -96,6 +105,7 @@ static inline int gen_pool_add(struct gen_pool *pool, unsigned long addr,
}
extern void gen_pool_destroy(struct gen_pool *);
extern unsigned long gen_pool_alloc(struct gen_pool *, size_t);
+extern unsigned long gen_pool_alloc_data(struct gen_pool *, size_t, void *data);
extern void *gen_pool_dma_alloc(struct gen_pool *pool, size_t size,
dma_addr_t *dma);
extern void gen_pool_free(struct gen_pool *, unsigned long, size_t);
@@ -108,14 +118,20 @@ extern void gen_pool_set_algo(struct gen_pool *pool, genpool_algo_t algo,
void *data);

extern 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);
+
+extern 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);

extern unsigned long gen_pool_first_fit_order_align(unsigned long *map,
unsigned long size, unsigned long start, unsigned int nr,
- void *data);
+ void *data, struct gen_pool *pool);

extern 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);

extern struct gen_pool *devm_gen_pool_create(struct device *dev,
int min_alloc_order, int nid);
diff --git a/lib/genalloc.c b/lib/genalloc.c
index d214866..b8762b1 100644
--- a/lib/genalloc.c
+++ b/lib/genalloc.c
@@ -269,6 +269,24 @@ EXPORT_SYMBOL(gen_pool_destroy);
*/
unsigned long gen_pool_alloc(struct gen_pool *pool, size_t size)
{
+ return gen_pool_alloc_data(pool, size, pool->data);
+}
+EXPORT_SYMBOL(gen_pool_alloc);
+
+/**
+ * gen_pool_alloc_data - allocate special memory from the pool
+ * @pool: pool to allocate from
+ * @size: number of bytes to allocate from the pool
+ * @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_data(struct gen_pool *pool, size_t size,
+ void *data)
+{
struct gen_pool_chunk *chunk;
unsigned long addr = 0;
int order = pool->min_alloc_order;
@@ -290,7 +308,7 @@ unsigned long gen_pool_alloc(struct gen_pool *pool, size_t size)
end_bit = chunk_size(chunk) >> order;
retry:
start_bit = pool->algo(chunk->bits, end_bit, start_bit, nbits,
- pool->data);
+ data, pool);
if (start_bit >= end_bit)
continue;
remain = bitmap_set_ll(chunk->bits, start_bit, nbits);
@@ -309,7 +327,7 @@ retry:
rcu_read_unlock();
return addr;
}
-EXPORT_SYMBOL(gen_pool_alloc);
+EXPORT_SYMBOL(gen_pool_alloc_data);

/**
* gen_pool_dma_alloc - allocate special memory from the pool for DMA usage
@@ -500,15 +518,42 @@ EXPORT_SYMBOL(gen_pool_set_algo);
* @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.
@@ -517,10 +562,11 @@ EXPORT_SYMBOL(gen_pool_first_fit);
* @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;

@@ -536,12 +582,14 @@ EXPORT_SYMBOL(gen_pool_first_fit_order_align);
* @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;
--
2.1.0.27.g96db324