ARM: dma-mapping: remove custom consistent dma region

This patch changes dma-mapping subsystem to use generic vmalloc areas
for all consistent dma allocations. This increases the total size limit
of the consistent allocations and removes platform hacks and a lot of
duplicated code.

Atomic allocations are served from special pool preallocated on boot,
because vmalloc areas cannot be reliably created in atomic context.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Kyungmin Park <kyungmin.park@samsung.com>
Reviewed-by: Minchan Kim <minchan@kernel.org>

1 files changed, 9 insertions, 1 deletions

diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index 11308f034f85..65fc4dc71108 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -1403,7 +1403,15 @@ struct vm_struct *get_vm_area_caller(unsigned long size, unsigned long flags,
                                                 -1, GFP_KERNEL, caller);
 }
 
-static struct vm_struct *find_vm_area(const void *addr)
+/**
+ *      find_vm_area  -  find a continuous kernel virtual area
+ *      @addr:          base address
+ *
+ *      Search for the kernel VM area starting at @addr, and return it.
+ *      It is up to the caller to do all required locking to keep the returned
+ *      pointer valid.
+ */
+struct vm_struct *find_vm_area(const void *addr)
 {
         struct vmap_area *va;