From 272baeeb6a98f5f746c2eeab4973c2df89e9d7ea Mon Sep 17 00:00:00 2001 From: Ben Hutchings Date: Tue, 29 Jan 2013 23:33:14 +0000 Subject: [PATCH] sfc: Properly distinguish RX buffer and DMA lengths Replace efx_nic::rx_buffer_len with efx_nic::rx_dma_len, the maximum RX DMA length. Signed-off-by: Ben Hutchings --- drivers/net/ethernet/sfc/efx.c | 11 +++++------ drivers/net/ethernet/sfc/net_driver.h | 5 ++--- drivers/net/ethernet/sfc/rx.c | 19 ++++++++----------- 3 files changed, 15 insertions(+), 20 deletions(-) diff --git a/drivers/net/ethernet/sfc/efx.c b/drivers/net/ethernet/sfc/efx.c index 5e1ddc559b4f..34b56ec87fba 100644 --- a/drivers/net/ethernet/sfc/efx.c +++ b/drivers/net/ethernet/sfc/efx.c @@ -639,12 +639,11 @@ static void efx_start_datapath(struct efx_nic *efx) * support the current MTU, including padding for header * alignment and overruns. */ - efx->rx_buffer_len = (max(EFX_PAGE_IP_ALIGN, NET_IP_ALIGN) + - EFX_MAX_FRAME_LEN(efx->net_dev->mtu) + - efx->type->rx_buffer_hash_size + - efx->type->rx_buffer_padding); - efx->rx_buffer_order = get_order(efx->rx_buffer_len + - sizeof(struct efx_rx_page_state)); + efx->rx_dma_len = (efx->type->rx_buffer_hash_size + + EFX_MAX_FRAME_LEN(efx->net_dev->mtu) + + efx->type->rx_buffer_padding); + efx->rx_buffer_order = get_order(sizeof(struct efx_rx_page_state) + + EFX_PAGE_IP_ALIGN + efx->rx_dma_len); /* We must keep at least one descriptor in a TX ring empty. * We could avoid this when the queue size does not exactly diff --git a/drivers/net/ethernet/sfc/net_driver.h b/drivers/net/ethernet/sfc/net_driver.h index f74411fc000c..fc6770e07d5a 100644 --- a/drivers/net/ethernet/sfc/net_driver.h +++ b/drivers/net/ethernet/sfc/net_driver.h @@ -669,8 +669,7 @@ struct vfdi_status; * @n_channels: Number of channels in use * @n_rx_channels: Number of channels used for RX (= number of RX queues) * @n_tx_channels: Number of channels used for TX - * @rx_buffer_len: RX buffer length, including start alignment but excluding - * any metadata + * @rx_dma_len: Current maximum RX DMA length * @rx_buffer_order: Order (log2) of number of pages for each RX buffer * @rx_hash_key: Toeplitz hash key for RSS * @rx_indir_table: Indirection table for RSS @@ -786,7 +785,7 @@ struct efx_nic { unsigned rss_spread; unsigned tx_channel_offset; unsigned n_tx_channels; - unsigned int rx_buffer_len; + unsigned int rx_dma_len; unsigned int rx_buffer_order; u8 rx_hash_key[40]; u32 rx_indir_table[128]; diff --git a/drivers/net/ethernet/sfc/rx.c b/drivers/net/ethernet/sfc/rx.c index e7aa28eb9327..31361db28f91 100644 --- a/drivers/net/ethernet/sfc/rx.c +++ b/drivers/net/ethernet/sfc/rx.c @@ -27,8 +27,9 @@ /* Number of RX descriptors pushed at once. */ #define EFX_RX_BATCH 8 -/* Maximum size of a buffer sharing a page */ -#define EFX_RX_HALF_PAGE ((PAGE_SIZE >> 1) - sizeof(struct efx_rx_page_state)) +/* Maximum length for an RX descriptor sharing a page */ +#define EFX_RX_HALF_PAGE ((PAGE_SIZE >> 1) - sizeof(struct efx_rx_page_state) \ + - EFX_PAGE_IP_ALIGN) /* Size of buffer allocated for skb header area. */ #define EFX_SKB_HEADERS 64u @@ -52,10 +53,6 @@ static inline unsigned int efx_rx_buf_offset(struct efx_nic *efx, { return buf->page_offset + efx->type->rx_buffer_hash_size; } -static inline unsigned int efx_rx_buf_size(struct efx_nic *efx) -{ - return PAGE_SIZE << efx->rx_buffer_order; -} static u8 *efx_rx_buf_eh(struct efx_nic *efx, struct efx_rx_buffer *buf) { @@ -105,7 +102,7 @@ static int efx_init_rx_buffers(struct efx_rx_queue *rx_queue) if (unlikely(page == NULL)) return -ENOMEM; dma_addr = dma_map_page(&efx->pci_dev->dev, page, 0, - efx_rx_buf_size(efx), + PAGE_SIZE << efx->rx_buffer_order, DMA_FROM_DEVICE); if (unlikely(dma_mapping_error(&efx->pci_dev->dev, dma_addr))) { __free_pages(page, efx->rx_buffer_order); @@ -124,12 +121,12 @@ static int efx_init_rx_buffers(struct efx_rx_queue *rx_queue) rx_buf->dma_addr = dma_addr + EFX_PAGE_IP_ALIGN; rx_buf->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->len = efx->rx_dma_len; rx_buf->flags = 0; ++rx_queue->added_count; ++state->refcnt; - if ((~count & 1) && (efx->rx_buffer_len <= EFX_RX_HALF_PAGE)) { + if ((~count & 1) && (efx->rx_dma_len <= EFX_RX_HALF_PAGE)) { /* Use the second half of the page */ get_page(page); dma_addr += (PAGE_SIZE >> 1); @@ -153,7 +150,7 @@ static void efx_unmap_rx_buffer(struct efx_nic *efx, if (--state->refcnt == 0) { dma_unmap_page(&efx->pci_dev->dev, state->dma_addr, - efx_rx_buf_size(efx), + PAGE_SIZE << efx->rx_buffer_order, DMA_FROM_DEVICE); } else if (used_len) { dma_sync_single_for_cpu(&efx->pci_dev->dev, @@ -221,7 +218,7 @@ static void efx_recycle_rx_buffer(struct efx_channel *channel, rx_buf->flags = 0; - if (efx->rx_buffer_len <= EFX_RX_HALF_PAGE && + if (efx->rx_dma_len <= EFX_RX_HALF_PAGE && page_count(rx_buf->page) == 1) efx_resurrect_rx_buffer(rx_queue, rx_buf); -- 2.20.1