[PATCH 1/2] lib/genalloc.c: Add algorithm, align and zeroed family of DMA allocators

From: Fredrik Noring
Date: Tue Jun 25 2019 - 11:06:18 EST


Provide the algorithm option to DMA allocators as well, along with
convenience variants for zeroed and aligned memory. The following
four functions are added:

- gen_pool_dma_alloc_algo()
- gen_pool_dma_alloc_align()
- gen_pool_dma_zalloc_algo()
- gen_pool_dma_zalloc_align()

Signed-off-by: Fredrik Noring <noring@xxxxxxxxxx>
---
Hi Christoph,

This patch is based on my v5.0.21 branch, with Laurentiu Tudor's other
local memory changes.

Fredrik
---
include/linux/genalloc.h | 10 +++-
lib/genalloc.c | 100 +++++++++++++++++++++++++++++++++++++--
2 files changed, 105 insertions(+), 5 deletions(-)

diff --git a/include/linux/genalloc.h b/include/linux/genalloc.h
--- a/include/linux/genalloc.h
+++ b/include/linux/genalloc.h
@@ -121,7 +121,15 @@ extern unsigned long gen_pool_alloc_algo(struct gen_pool *, size_t,
genpool_algo_t algo, void *data);
extern void *gen_pool_dma_alloc(struct gen_pool *pool, size_t size,
dma_addr_t *dma);
-void *gen_pool_dma_zalloc(struct gen_pool *pool, size_t size, dma_addr_t *dma);
+extern void *gen_pool_dma_alloc_algo(struct gen_pool *pool, size_t size,
+ dma_addr_t *dma, genpool_algo_t algo, void *data);
+extern void *gen_pool_dma_alloc_align(struct gen_pool *pool, size_t size,
+ dma_addr_t *dma, int align);
+extern void *gen_pool_dma_zalloc(struct gen_pool *pool, size_t size, dma_addr_t *dma);
+extern void *gen_pool_dma_zalloc_algo(struct gen_pool *pool, size_t size,
+ dma_addr_t *dma, genpool_algo_t algo, void *data);
+extern void *gen_pool_dma_zalloc_align(struct gen_pool *pool, size_t size,
+ dma_addr_t *dma, int align);
extern void gen_pool_free(struct gen_pool *, unsigned long, size_t);
extern void gen_pool_for_each_chunk(struct gen_pool *,
void (*)(struct gen_pool *, struct gen_pool_chunk *, void *), void *);
diff --git a/lib/genalloc.c b/lib/genalloc.c
--- a/lib/genalloc.c
+++ b/lib/genalloc.c
@@ -347,13 +347,35 @@ EXPORT_SYMBOL(gen_pool_alloc_algo);
* Return: virtual address of the allocated memory, or %NULL on failure
*/
void *gen_pool_dma_alloc(struct gen_pool *pool, size_t size, dma_addr_t *dma)
+{
+ return gen_pool_dma_alloc_algo(pool, size, dma, pool->algo, pool->data);
+}
+EXPORT_SYMBOL(gen_pool_dma_alloc);
+
+/**
+ * gen_pool_dma_alloc_algo - allocate special memory from the pool for DMA
+ * usage with the given pool algorithm
+ * @pool: pool to allocate from
+ * @size: number of bytes to allocate from the pool
+ * @dma: DMA-view physical address return value. Use %NULL if unneeded.
+ * @algo: algorithm passed from caller
+ * @data: data passed to algorithm
+ *
+ * Allocate the requested number of bytes from the specified pool. Uses the
+ * given pool allocation function. Can not be used in NMI handler on
+ * architectures without NMI-safe cmpxchg implementation.
+ *
+ * Return: virtual address of the allocated memory, or %NULL on failure
+ */
+void *gen_pool_dma_alloc_algo(struct gen_pool *pool, size_t size,
+ dma_addr_t *dma, genpool_algo_t algo, void *data)
{
unsigned long vaddr;

if (!pool)
return NULL;

- vaddr = gen_pool_alloc(pool, size);
+ vaddr = gen_pool_alloc_algo(pool, size, algo, data);
if (!vaddr)
return NULL;

@@ -362,7 +384,31 @@ void *gen_pool_dma_alloc(struct gen_pool *pool, size_t size, dma_addr_t *dma)

return (void *)vaddr;
}
-EXPORT_SYMBOL(gen_pool_dma_alloc);
+EXPORT_SYMBOL(gen_pool_dma_alloc_algo);
+
+/**
+ * gen_pool_dma_alloc_align - allocate special memory from the pool for DMA
+ * usage with the given alignment
+ * @pool: pool to allocate from
+ * @size: number of bytes to allocate from the pool
+ * @dma: DMA-view physical address return value. Use %NULL if unneeded.
+ * @align: alignment in bytes for starting address
+ *
+ * Allocate the requested number bytes from the specified pool, with the given
+ * alignment restriction. Can not be used in NMI handler on architectures
+ * without NMI-safe cmpxchg implementation.
+ *
+ * Return: virtual address of the allocated memory, or %NULL on failure
+ */
+void *gen_pool_dma_alloc_align(struct gen_pool *pool, size_t size,
+ dma_addr_t *dma, int align)
+{
+ struct genpool_data_align data = { .align = align };
+
+ return gen_pool_dma_alloc_algo(pool, size, dma,
+ gen_pool_first_fit_align, &data);
+}
+EXPORT_SYMBOL(gen_pool_dma_alloc_align);

/**
* gen_pool_dma_zalloc - allocate special zeroed memory from the pool for
@@ -380,14 +426,60 @@ EXPORT_SYMBOL(gen_pool_dma_alloc);
*/
void *gen_pool_dma_zalloc(struct gen_pool *pool, size_t size, dma_addr_t *dma)
{
- void *vaddr = gen_pool_dma_alloc(pool, size, dma);
+ return gen_pool_dma_zalloc_algo(pool, size, dma, pool->algo, pool->data);
+}
+EXPORT_SYMBOL(gen_pool_dma_zalloc);
+
+/**
+ * gen_pool_dma_zalloc_algo - allocate special zeroed memory from the pool for
+ * DMA usage with the given pool algorithm
+ * @pool: pool to allocate from
+ * @size: number of bytes to allocate from the pool
+ * @dma: DMA-view physical address return value. Use %NULL if unneeded.
+ * @algo: algorithm passed from caller
+ * @data: data passed to algorithm
+ *
+ * Allocate the requested number of zeroed bytes from the specified pool. Uses
+ * the given pool allocation function. Can not be used in NMI handler on
+ * architectures without NMI-safe cmpxchg implementation.
+ *
+ * Return: virtual address of the allocated zeroed memory, or %NULL on failure
+ */
+void *gen_pool_dma_zalloc_algo(struct gen_pool *pool, size_t size,
+ dma_addr_t *dma, genpool_algo_t algo, void *data)
+{
+ void *vaddr = gen_pool_dma_alloc_algo(pool, size, dma, algo, data);

if (vaddr)
memset(vaddr, 0, size);

return vaddr;
}
-EXPORT_SYMBOL(gen_pool_dma_zalloc);
+EXPORT_SYMBOL(gen_pool_dma_zalloc_algo);
+
+/**
+ * gen_pool_dma_zalloc_align - allocate special zeroed memory from the pool for
+ * DMA usage with the given alignment
+ * @pool: pool to allocate from
+ * @size: number of bytes to allocate from the pool
+ * @dma: DMA-view physical address return value. Use %NULL if unneeded.
+ * @align: alignment in bytes for starting address
+ *
+ * Allocate the requested number of zeroed bytes from the specified pool,
+ * with the given alignment restriction. Can not be used in NMI handler on
+ * architectures without NMI-safe cmpxchg implementation.
+ *
+ * Return: virtual address of the allocated zeroed memory, or %NULL on failure
+ */
+void *gen_pool_dma_zalloc_align(struct gen_pool *pool, size_t size,
+ dma_addr_t *dma, int align)
+{
+ struct genpool_data_align data = { .align = align };
+
+ return gen_pool_dma_zalloc_algo(pool, size, dma,
+ gen_pool_first_fit_align, &data);
+}
+EXPORT_SYMBOL(gen_pool_dma_zalloc_align);

/**
* gen_pool_free - free allocated special memory back to the pool
--
2.21.0