mm: add dma_pool_zalloc() call to DMA API

Add a wrapper function for dma_pool_alloc() to get zeroed memory.

Signed-off-by: Sean O. Stalley <sean.stalley@intel.com>
Cc: Vinod Koul <vinod.koul@intel.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Gilles Muller <Gilles.Muller@lip6.fr>
Cc: Nicolas Palix <nicolas.palix@imag.fr>
Cc: Michal Marek <mmarek@suse.cz>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/Documentation/DMA-API.txt b/Documentation/DMA-API.txt
index 7eba542eff7c8317d0da92ea4b638076b4f0f996..edccacd4f048a13e8afdb63db7d98ad41667a503 100644 (file)
--- a/Documentation/DMA-API.txt
+++ b/Documentation/DMA-API.txt
@@ -104,6 +104,13 @@ crossing restrictions, pass 0 for alloc; passing 4096 says memory allocated
 from this pool must not cross 4KByte boundaries.
 
 
+       void *dma_pool_zalloc(struct dma_pool *pool, gfp_t mem_flags,
+                             dma_addr_t *handle)
+
+Wraps dma_pool_alloc() and also zeroes the returned memory if the
+allocation attempt succeeded.
+
+
        void *dma_pool_alloc(struct dma_pool *pool, gfp_t gfp_flags,
                        dma_addr_t *dma_handle);
 

diff --git a/include/linux/dmapool.h b/include/linux/dmapool.h
index e1043f79122f827405afbb7b176d14611702098a..53ba737505df31c7673c814d8d00884f72a17cb1 100644 (file)
--- a/include/linux/dmapool.h
+++ b/include/linux/dmapool.h
@@ -24,6 +24,12 @@ void dma_pool_destroy(struct dma_pool *pool);
 void *dma_pool_alloc(struct dma_pool *pool, gfp_t mem_flags,
                     dma_addr_t *handle);
 
+static inline void *dma_pool_zalloc(struct dma_pool *pool, gfp_t mem_flags,
+                                   dma_addr_t *handle)
+{
+       return dma_pool_alloc(pool, mem_flags | __GFP_ZERO, handle);
+}
+
 void dma_pool_free(struct dma_pool *pool, void *vaddr, dma_addr_t addr);
 
 /*