From 1567b85eb8ad2d0fe8d77e50118e876df565d9c7 Mon Sep 17 00:00:00 2001 From: Ilias Apalodimas Date: Wed, 13 Feb 2019 02:55:45 +0100 Subject: 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 Signed-off-by: Jesper Dangaard Brouer Signed-off-by: David S. Miller --- net/core/page_pool.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) (limited to 'net/core') 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 */ -- cgit