dmapool: rearrange page alloc failure handling

Handle the error in a condition so the good path can be in the normal
flow.

Link: https://lkml.kernel.org/r/20230126215125.4069751-8-kbusch@meta.com
Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Tony Battersby <tonyb@cybernetics.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/mm/dmapool.c b/mm/dmapool.c
index 30b069e..900f2af 100644 (file)
--- a/mm/dmapool.c
+++ b/mm/dmapool.c
@@ -292,17 +292,19 @@ static struct dma_page *pool_alloc_page(struct dma_pool *pool, gfp_t mem_flags)
        page = kmalloc(sizeof(*page), mem_flags);
        if (!page)
                return NULL;
+
        page->vaddr = dma_alloc_coherent(pool->dev, pool->allocation,
                                         &page->dma, mem_flags);
-       if (page->vaddr) {
-               pool_init_page(pool, page);
-               pool_initialise_page(pool, page);
-               page->in_use = 0;
-               page->offset = 0;
-       } else {
+       if (!page->vaddr) {
                kfree(page);
-               page = NULL;
+               return NULL;
        }
+
+       pool_init_page(pool, page);
+       pool_initialise_page(pool, page);
+       page->in_use = 0;
+       page->offset = 0;
+
        return page;
 }