X-Git-Url: https://git.proxmox.com/?a=blobdiff_plain;f=lib%2Fgenalloc.c;h=dda31168844f42c9c6fe2f9c9d25526e30884529;hb=db0b2d01163cc3050eb52a979541e0d16553be48;hp=26cf20be72b74013dd874abc551c3f9a412bc1b6;hpb=7c6a4acc645cdd938300d5f9bb367f72170af310;p=mirror_ubuntu-bionic-kernel.git

diff --git a/lib/genalloc.c b/lib/genalloc.c
index 26cf20be72b7..dda31168844f 100644
--- a/lib/genalloc.c
+++ b/lib/genalloc.c
@@ -312,6 +312,34 @@ retry:
 }
 EXPORT_SYMBOL(gen_pool_alloc);
 
+/**
+ * gen_pool_dma_alloc - allocate special memory from the pool for DMA usage
+ * @pool: pool to allocate from
+ * @size: number of bytes to allocate from the pool
+ * @dma: dma-view physical address
+ *
+ * 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.
+ */
+void *gen_pool_dma_alloc(struct gen_pool *pool, size_t size, dma_addr_t *dma)
+{
+	unsigned long vaddr;
+
+	if (!pool)
+		return NULL;
+
+	vaddr = gen_pool_alloc(pool, size);
+	if (!vaddr)
+		return NULL;
+
+	*dma = gen_pool_virt_to_phys(pool, vaddr);
+
+	return (void *)vaddr;
+}
+EXPORT_SYMBOL(gen_pool_dma_alloc);
+
 /**
  * gen_pool_free - free allocated special memory back to the pool
  * @pool: pool to free to