On Mon, Mar 29, 2021 at 07:44:31PM +0100, Matthew Wilcox wrote:

On Mon, Mar 29, 2021 at 11:25:53AM -0700, Minchan Kim wrote:

quoted

size_t in cma_alloc is confusing since it makes people think
it's byte count, not pages. Fix it.

i think it has to be unsigned long.

67a2e213e7e937c41c52ab5bc46bf3f4de469f6e

Thanks for the pinter. I wanted to have the smallest change.
The commit leads me to change cma_release, trace_cma_alloc,
cma_clear_bitmap and front_contig_range as well.(Not sure
we have more. Will check).

Ccing david@redhat.com for upcoming changing free_contig_range.

quoted

Link: https://lore.kernel.org/linux-mm/20210324043434.GP1719932@casper.infradead.org/ (local)
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Minchan Kim <minchan@kernel.org>
---
 include/linux/cma.h | 2 +-
 mm/cma.c            | 8 ++++----
 2 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/include/linux/cma.h b/include/linux/cma.h
index 217999c8a762..a873edc20ca2 100644
--- a/include/linux/cma.h
+++ b/include/linux/cma.h

@@ -44,7 +44,7 @@ extern int cma_init_reserved_mem(phys_addr_t base, phys_addr_t size,
 					unsigned int order_per_bit,
 					const char *name,
 					struct cma **res_cma);
-extern struct page *cma_alloc(struct cma *cma, size_t count, unsigned int align,
+extern struct page *cma_alloc(struct cma *cma, unsigned int count, unsigned int align,
 			      bool no_warn);
 extern bool cma_release(struct cma *cma, const struct page *pages, unsigned int count);
 

diff --git a/mm/cma.c b/mm/cma.c
index 08c45157911a..24dc01e26d45 100644
--- a/mm/cma.c
+++ b/mm/cma.c

@@ -423,21 +423,21 @@ static inline void cma_debug_show_areas(struct cma *cma) { }
  * 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, unsigned int count, unsigned int align,
 		       bool no_warn)
 {
 	unsigned long mask, offset;
 	unsigned long pfn = -1;
 	unsigned long start = 0;
 	unsigned long bitmap_maxno, bitmap_no, bitmap_count;
-	size_t i;
+	unsigned int i;
 	struct page *page = NULL;
 	int ret = -ENOMEM;
 
 	if (!cma || !cma->count || !cma->bitmap)
 		goto out;
 
-	pr_debug("%s(cma %p, count %zu, align %d)\n", __func__, (void *)cma,
+	pr_debug("%s(cma %p, count %u, align %d)\n", __func__, (void *)cma,
 		 count, align);
 
 	if (!count)

@@ -500,7 +500,7 @@ struct page *cma_alloc(struct cma *cma, size_t count, unsigned int align,
 	}
 
 	if (ret && !no_warn) {
-		pr_err_ratelimited("%s: %s: alloc failed, req-size: %zu pages, ret: %d\n",
+		pr_err_ratelimited("%s: %s: alloc failed, req-size: %u pages, ret: %d\n",
 				   __func__, cma->name, count, ret);
 		cma_debug_show_areas(cma);
 	}

-- 
2.31.0.291.g576ba9dcdaf-goog