diff options
| author |   Ilias Apalodimas <ilias.apalodimas@linaro.org> | 2019-02-13 02:55:45 +0100 |
|---|---|---|
| committer |   David S. Miller <davem@davemloft.net> | 2019-02-13 22:00:16 -0800 |
| commit | 1567b85eb8ad2d0fe8d77e50118e876df565d9c7 (patch) | |
| tree | d7357f5cf9befd591a7fc17bf120a4210d040eac /net/core | |
| parent | mm: add dma_addr_t to struct page (diff) | |
| download | linux-dev-1567b85eb8ad2d0fe8d77e50118e876df565d9c7.tar.xz linux-dev-1567b85eb8ad2d0fe8d77e50118e876df565d9c7.zip | |
net: page_pool: don't use page->private to store dma_addr_t
As pointed out by David Miller the current page_pool implementation
stores dma_addr_t in page->private.
This won't work on 32-bit platforms with 64-bit DMA addresses since the
page->private is an unsigned long and the dma_addr_t a u64.
A previous patch is adding dma_addr_t on struct page to accommodate this.
This patch adapts the page_pool related functions to use the newly added
struct for storing and retrieving DMA addresses from network drivers.
Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/core')
| -rw-r--r-- | net/core/page_pool.c | 13 |
1 files changed, 9 insertions, 4 deletions
diff --git a/net/core/page_pool.c b/net/core/page_pool.c index 43a932cb609b..897a69a1477e 100644 --- a/net/core/page_pool.c +++ b/net/core/page_pool.c @@ -136,7 +136,9 @@ static struct page *__page_pool_alloc_pages_slow(struct page_pool *pool, if (!(pool->p.flags & PP_FLAG_DMA_MAP)) goto skip_dma_map; - /* Setup DMA mapping: use page->private for DMA-addr + /* Setup DMA mapping: use 'struct page' area for storing DMA-addr + * since dma_addr_t can be either 32 or 64 bits and does not always fit + * into page private data (i.e 32bit cpu with 64bit DMA caps) * This mapping is kept for lifetime of page, until leaving pool. */ dma = dma_map_page(pool->p.dev, page, 0, @@ -146,7 +148,7 @@ static struct page *__page_pool_alloc_pages_slow(struct page_pool *pool, put_page(page); return NULL; } - set_page_private(page, dma); /* page->private = dma; */ + page->dma_addr = dma; skip_dma_map: /* When page just alloc'ed is should/must have refcnt 1. */ @@ -175,13 +177,16 @@ EXPORT_SYMBOL(page_pool_alloc_pages); static void __page_pool_clean_page(struct page_pool *pool, struct page *page) { + dma_addr_t dma; + if (!(pool->p.flags & PP_FLAG_DMA_MAP)) return; + dma = page->dma_addr; /* DMA unmap */ - dma_unmap_page(pool->p.dev, page_private(page), + dma_unmap_page(pool->p.dev, dma, PAGE_SIZE << pool->p.order, pool->p.dma_dir); - set_page_private(page, 0); + page->dma_addr = 0; } /* Return a page to the page allocator, cleaning up our state */ |