mm: cma_alloc: allow to specify GFP mask

Most users of this interface just want to use it with the default
GFP_KERNEL flags, but for cases where DMA memory is allocated it may be
called from a different context.

No functional change yet, just passing through the flag to the
underlying alloc_contig_range function.

Link: http://lkml.kernel.org/r/20170127172328.18574-2-l.stach@pengutronix.de
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Radim Krcmar <rkrcmar@redhat.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Alexander Graf <agraf@suse.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2 files changed, 4 insertions, 3 deletions

diff --git a/mm/cma.c b/mm/cma.c
index c6aed23ca6df..2906ae5a83ff 100644
--- a/mm/cma.c
+++ b/mm/cma.c
@@ -357,7 +357,8 @@ err:
  * This function allocates part of contiguous memory on specific
  * contiguous memory area.
  */
-struct page *cma_alloc(struct cma *cma, size_t count, unsigned int align)
+struct page *cma_alloc(struct cma *cma, size_t count, unsigned int align,
+                       gfp_t gfp_mask)
 {
         unsigned long mask, offset;
         unsigned long pfn = -1;
@@ -403,7 +404,7 @@ struct page *cma_alloc(struct cma *cma, size_t count, unsigned int align)
                 pfn = cma->base_pfn + (bitmap_no << cma->order_per_bit);
                 mutex_lock(&cma_mutex);
                 ret = alloc_contig_range(pfn, pfn + count, MIGRATE_CMA,
-                                         GFP_KERNEL);
+                                         gfp_mask);
                 mutex_unlock(&cma_mutex);
                 if (ret == 0) {
                         page = pfn_to_page(pfn);
diff --git a/mm/cma_debug.c b/mm/cma_debug.c
index f8e4b60db167..ffc0c3d0ae64 100644
--- a/mm/cma_debug.c
+++ b/mm/cma_debug.c
@@ -138,7 +138,7 @@ static int cma_alloc_mem(struct cma *cma, int count)
         if (!mem)
                 return -ENOMEM;
 
-        p = cma_alloc(cma, count, 0);
+        p = cma_alloc(cma, count, 0, GFP_KERNEL);
         if (!p) {
                 kfree(mem);
                 return -ENOMEM;