From 4b8fd2aa494aff51404a4afa0fe36475fd419b76 Mon Sep 17 00:00:00 2001 From: Ben Hutchings Date: Thu, 10 Jan 2013 23:51:54 +0000 Subject: [PATCH] sfc: Fix efx_rx_buf_offset() in the presence of swiotlb [ Upstream commits b590ace09d51cd39744e0f7662c5e4a0d1b5d952 and c73e787a8db9117d59b5180baf83203a42ecadca ] We assume that the mapping between DMA and virtual addresses is done on whole pages, so we can find the page offset of an RX buffer using the lower bits of the DMA address. However, swiotlb maps in units of 2K, breaking this assumption. Add an explicit page_offset field to struct efx_rx_buffer. Signed-off-by: Ben Hutchings Signed-off-by: Greg Kroah-Hartman --- drivers/net/ethernet/sfc/net_driver.h | 4 +++- drivers/net/ethernet/sfc/rx.c | 10 +++++----- 2 files changed, 8 insertions(+), 6 deletions(-) diff --git a/drivers/net/ethernet/sfc/net_driver.h b/drivers/net/ethernet/sfc/net_driver.h index 9c32e05e9cde..b71ef1400857 100644 --- a/drivers/net/ethernet/sfc/net_driver.h +++ b/drivers/net/ethernet/sfc/net_driver.h @@ -206,6 +206,7 @@ struct efx_tx_queue { * Will be %NULL if the buffer slot is currently free. * @page: The associated page buffer. Valif iff @flags & %EFX_RX_BUF_PAGE. * Will be %NULL if the buffer slot is currently free. + * @page_offset: Offset within page. Valid iff @flags & %EFX_RX_BUF_PAGE. * @len: Buffer length, in bytes. * @flags: Flags for buffer and packet state. */ @@ -215,7 +216,8 @@ struct efx_rx_buffer { struct sk_buff *skb; struct page *page; } u; - unsigned int len; + u16 page_offset; + u16 len; u16 flags; }; #define EFX_RX_BUF_PAGE 0x0001 diff --git a/drivers/net/ethernet/sfc/rx.c b/drivers/net/ethernet/sfc/rx.c index c9766cad98f5..7b3c068a9f52 100644 --- a/drivers/net/ethernet/sfc/rx.c +++ b/drivers/net/ethernet/sfc/rx.c @@ -95,11 +95,7 @@ static unsigned int rx_refill_limit = 95; static inline unsigned int efx_rx_buf_offset(struct efx_nic *efx, struct efx_rx_buffer *buf) { - /* Offset is always within one page, so we don't need to consider - * the page order. - */ - return ((unsigned int) buf->dma_addr & (PAGE_SIZE - 1)) + - efx->type->rx_buffer_hash_size; + return buf->page_offset + efx->type->rx_buffer_hash_size; } static inline unsigned int efx_rx_buf_size(struct efx_nic *efx) { @@ -193,6 +189,7 @@ static int efx_init_rx_buffers_page(struct efx_rx_queue *rx_queue) struct efx_rx_buffer *rx_buf; struct page *page; void *page_addr; + unsigned int page_offset; struct efx_rx_page_state *state; dma_addr_t dma_addr; unsigned index, count; @@ -219,12 +216,14 @@ static int efx_init_rx_buffers_page(struct efx_rx_queue *rx_queue) page_addr += sizeof(struct efx_rx_page_state); dma_addr += sizeof(struct efx_rx_page_state); + page_offset = sizeof(struct efx_rx_page_state); split: index = rx_queue->added_count & rx_queue->ptr_mask; rx_buf = efx_rx_buffer(rx_queue, index); rx_buf->dma_addr = dma_addr + EFX_PAGE_IP_ALIGN; rx_buf->u.page = page; + rx_buf->page_offset = page_offset + EFX_PAGE_IP_ALIGN; rx_buf->len = efx->rx_buffer_len - EFX_PAGE_IP_ALIGN; rx_buf->flags = EFX_RX_BUF_PAGE; ++rx_queue->added_count; @@ -236,6 +235,7 @@ static int efx_init_rx_buffers_page(struct efx_rx_queue *rx_queue) get_page(page); dma_addr += (PAGE_SIZE >> 1); page_addr += (PAGE_SIZE >> 1); + page_offset += (PAGE_SIZE >> 1); ++count; goto split; } -- 2.39.5