[RFC PATCH 09/12] cma: Introduce cma_for_each_area

[Laura Abbott <labbott@redhat.com>]

Frameworks (e.g. Ion) may want to iterate over each possible CMA area to
allow for enumeration. Introduce a function to allow a callback.

Signed-off-by: Laura Abbott <labbott@redhat.com>
---
 include/linux/cma.h |  2 ++
 mm/cma.c            | 14 ++++++++++++++
 2 files changed, 16 insertions(+)

diff --git a/include/linux/cma.h b/include/linux/cma.h
index 49f98ea..b521e3c 100644
--- a/include/linux/cma.h
+++ b/include/linux/cma.h
@@ -33,4 +33,6 @@ extern int cma_init_reserved_mem(phys_addr_t base, phys_addr_t size,
 					struct cma **res_cma);
 extern struct page *cma_alloc(struct cma *cma, size_t count, unsigned int align);
 extern bool cma_release(struct cma *cma, const struct page *pages, unsigned int count);
+
+extern int cma_for_each_area(int (*it)(struct cma *cma, void *data), void *data);
 #endif
diff --git a/mm/cma.c b/mm/cma.c
index 4a93d2b..a430df0 100644
--- a/mm/cma.c
+++ b/mm/cma.c
@@ -464,3 +464,17 @@ bool cma_release(struct cma *cma, const struct page *pages, unsigned int count)
 
 	return true;
 }
+
+int cma_for_each_area(int (*it)(struct cma *cma, void *data), void *data)
+{
+	int i;
+
+	for (i = 0; i < cma_area_count; i++) {
+		int ret = it(&cma_areas[i], data);
+
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
-- 
2.7.4