1874aeea5SJeff Kirsher /**************************************************************************** 2874aeea5SJeff Kirsher * Driver for Solarflare Solarstorm network controllers and boards 3874aeea5SJeff Kirsher * Copyright 2005-2006 Fen Systems Ltd. 4874aeea5SJeff Kirsher * Copyright 2005-2010 Solarflare Communications Inc. 5874aeea5SJeff Kirsher * 6874aeea5SJeff Kirsher * This program is free software; you can redistribute it and/or modify it 7874aeea5SJeff Kirsher * under the terms of the GNU General Public License version 2 as published 8874aeea5SJeff Kirsher * by the Free Software Foundation, incorporated herein by reference. 9874aeea5SJeff Kirsher */ 10874aeea5SJeff Kirsher 11874aeea5SJeff Kirsher #include <linux/pci.h> 12874aeea5SJeff Kirsher #include <linux/tcp.h> 13874aeea5SJeff Kirsher #include <linux/ip.h> 14874aeea5SJeff Kirsher #include <linux/in.h> 15874aeea5SJeff Kirsher #include <linux/ipv6.h> 16874aeea5SJeff Kirsher #include <linux/slab.h> 17874aeea5SJeff Kirsher #include <net/ipv6.h> 18874aeea5SJeff Kirsher #include <linux/if_ether.h> 19874aeea5SJeff Kirsher #include <linux/highmem.h> 20874aeea5SJeff Kirsher #include "net_driver.h" 21874aeea5SJeff Kirsher #include "efx.h" 22874aeea5SJeff Kirsher #include "nic.h" 23874aeea5SJeff Kirsher #include "workarounds.h" 24874aeea5SJeff Kirsher 25874aeea5SJeff Kirsher /* 26874aeea5SJeff Kirsher * TX descriptor ring full threshold 27874aeea5SJeff Kirsher * 28874aeea5SJeff Kirsher * The tx_queue descriptor ring fill-level must fall below this value 29874aeea5SJeff Kirsher * before we restart the netif queue 30874aeea5SJeff Kirsher */ 31874aeea5SJeff Kirsher #define EFX_TXQ_THRESHOLD(_efx) ((_efx)->txq_entries / 2u) 32874aeea5SJeff Kirsher 33874aeea5SJeff Kirsher static void efx_dequeue_buffer(struct efx_tx_queue *tx_queue, 34874aeea5SJeff Kirsher struct efx_tx_buffer *buffer) 35874aeea5SJeff Kirsher { 36874aeea5SJeff Kirsher if (buffer->unmap_len) { 37874aeea5SJeff Kirsher struct pci_dev *pci_dev = tx_queue->efx->pci_dev; 38874aeea5SJeff Kirsher dma_addr_t unmap_addr = (buffer->dma_addr + buffer->len - 39874aeea5SJeff Kirsher buffer->unmap_len); 40874aeea5SJeff Kirsher if (buffer->unmap_single) 41874aeea5SJeff Kirsher pci_unmap_single(pci_dev, unmap_addr, buffer->unmap_len, 42874aeea5SJeff Kirsher PCI_DMA_TODEVICE); 43874aeea5SJeff Kirsher else 44874aeea5SJeff Kirsher pci_unmap_page(pci_dev, unmap_addr, buffer->unmap_len, 45874aeea5SJeff Kirsher PCI_DMA_TODEVICE); 46874aeea5SJeff Kirsher buffer->unmap_len = 0; 47874aeea5SJeff Kirsher buffer->unmap_single = false; 48874aeea5SJeff Kirsher } 49874aeea5SJeff Kirsher 50874aeea5SJeff Kirsher if (buffer->skb) { 51874aeea5SJeff Kirsher dev_kfree_skb_any((struct sk_buff *) buffer->skb); 52874aeea5SJeff Kirsher buffer->skb = NULL; 53874aeea5SJeff Kirsher netif_vdbg(tx_queue->efx, tx_done, tx_queue->efx->net_dev, 54874aeea5SJeff Kirsher "TX queue %d transmission id %x complete\n", 55874aeea5SJeff Kirsher tx_queue->queue, tx_queue->read_count); 56874aeea5SJeff Kirsher } 57874aeea5SJeff Kirsher } 58874aeea5SJeff Kirsher 59874aeea5SJeff Kirsher /** 60874aeea5SJeff Kirsher * struct efx_tso_header - a DMA mapped buffer for packet headers 61874aeea5SJeff Kirsher * @next: Linked list of free ones. 62874aeea5SJeff Kirsher * The list is protected by the TX queue lock. 63874aeea5SJeff Kirsher * @dma_unmap_len: Length to unmap for an oversize buffer, or 0. 64874aeea5SJeff Kirsher * @dma_addr: The DMA address of the header below. 65874aeea5SJeff Kirsher * 66874aeea5SJeff Kirsher * This controls the memory used for a TSO header. Use TSOH_DATA() 67874aeea5SJeff Kirsher * to find the packet header data. Use TSOH_SIZE() to calculate the 68874aeea5SJeff Kirsher * total size required for a given packet header length. TSO headers 69874aeea5SJeff Kirsher * in the free list are exactly %TSOH_STD_SIZE bytes in size. 70874aeea5SJeff Kirsher */ 71874aeea5SJeff Kirsher struct efx_tso_header { 72874aeea5SJeff Kirsher union { 73874aeea5SJeff Kirsher struct efx_tso_header *next; 74874aeea5SJeff Kirsher size_t unmap_len; 75874aeea5SJeff Kirsher }; 76874aeea5SJeff Kirsher dma_addr_t dma_addr; 77874aeea5SJeff Kirsher }; 78874aeea5SJeff Kirsher 79874aeea5SJeff Kirsher static int efx_enqueue_skb_tso(struct efx_tx_queue *tx_queue, 80874aeea5SJeff Kirsher struct sk_buff *skb); 81874aeea5SJeff Kirsher static void efx_fini_tso(struct efx_tx_queue *tx_queue); 82874aeea5SJeff Kirsher static void efx_tsoh_heap_free(struct efx_tx_queue *tx_queue, 83874aeea5SJeff Kirsher struct efx_tso_header *tsoh); 84874aeea5SJeff Kirsher 85874aeea5SJeff Kirsher static void efx_tsoh_free(struct efx_tx_queue *tx_queue, 86874aeea5SJeff Kirsher struct efx_tx_buffer *buffer) 87874aeea5SJeff Kirsher { 88874aeea5SJeff Kirsher if (buffer->tsoh) { 89874aeea5SJeff Kirsher if (likely(!buffer->tsoh->unmap_len)) { 90874aeea5SJeff Kirsher buffer->tsoh->next = tx_queue->tso_headers_free; 91874aeea5SJeff Kirsher tx_queue->tso_headers_free = buffer->tsoh; 92874aeea5SJeff Kirsher } else { 93874aeea5SJeff Kirsher efx_tsoh_heap_free(tx_queue, buffer->tsoh); 94874aeea5SJeff Kirsher } 95874aeea5SJeff Kirsher buffer->tsoh = NULL; 96874aeea5SJeff Kirsher } 97874aeea5SJeff Kirsher } 98874aeea5SJeff Kirsher 99874aeea5SJeff Kirsher 100874aeea5SJeff Kirsher static inline unsigned 101874aeea5SJeff Kirsher efx_max_tx_len(struct efx_nic *efx, dma_addr_t dma_addr) 102874aeea5SJeff Kirsher { 103874aeea5SJeff Kirsher /* Depending on the NIC revision, we can use descriptor 104874aeea5SJeff Kirsher * lengths up to 8K or 8K-1. However, since PCI Express 105874aeea5SJeff Kirsher * devices must split read requests at 4K boundaries, there is 106874aeea5SJeff Kirsher * little benefit from using descriptors that cross those 107874aeea5SJeff Kirsher * boundaries and we keep things simple by not doing so. 108874aeea5SJeff Kirsher */ 109874aeea5SJeff Kirsher unsigned len = (~dma_addr & 0xfff) + 1; 110874aeea5SJeff Kirsher 111874aeea5SJeff Kirsher /* Work around hardware bug for unaligned buffers. */ 112874aeea5SJeff Kirsher if (EFX_WORKAROUND_5391(efx) && (dma_addr & 0xf)) 113874aeea5SJeff Kirsher len = min_t(unsigned, len, 512 - (dma_addr & 0xf)); 114874aeea5SJeff Kirsher 115874aeea5SJeff Kirsher return len; 116874aeea5SJeff Kirsher } 117874aeea5SJeff Kirsher 118874aeea5SJeff Kirsher /* 119874aeea5SJeff Kirsher * Add a socket buffer to a TX queue 120874aeea5SJeff Kirsher * 121874aeea5SJeff Kirsher * This maps all fragments of a socket buffer for DMA and adds them to 122874aeea5SJeff Kirsher * the TX queue. The queue's insert pointer will be incremented by 123874aeea5SJeff Kirsher * the number of fragments in the socket buffer. 124874aeea5SJeff Kirsher * 125874aeea5SJeff Kirsher * If any DMA mapping fails, any mapped fragments will be unmapped, 126874aeea5SJeff Kirsher * the queue's insert pointer will be restored to its original value. 127874aeea5SJeff Kirsher * 128874aeea5SJeff Kirsher * This function is split out from efx_hard_start_xmit to allow the 129874aeea5SJeff Kirsher * loopback test to direct packets via specific TX queues. 130874aeea5SJeff Kirsher * 131874aeea5SJeff Kirsher * Returns NETDEV_TX_OK or NETDEV_TX_BUSY 132874aeea5SJeff Kirsher * You must hold netif_tx_lock() to call this function. 133874aeea5SJeff Kirsher */ 134874aeea5SJeff Kirsher netdev_tx_t efx_enqueue_skb(struct efx_tx_queue *tx_queue, struct sk_buff *skb) 135874aeea5SJeff Kirsher { 136874aeea5SJeff Kirsher struct efx_nic *efx = tx_queue->efx; 137874aeea5SJeff Kirsher struct pci_dev *pci_dev = efx->pci_dev; 138874aeea5SJeff Kirsher struct efx_tx_buffer *buffer; 139874aeea5SJeff Kirsher skb_frag_t *fragment; 140874aeea5SJeff Kirsher unsigned int len, unmap_len = 0, fill_level, insert_ptr; 141874aeea5SJeff Kirsher dma_addr_t dma_addr, unmap_addr = 0; 142874aeea5SJeff Kirsher unsigned int dma_len; 143874aeea5SJeff Kirsher bool unmap_single; 144874aeea5SJeff Kirsher int q_space, i = 0; 145874aeea5SJeff Kirsher netdev_tx_t rc = NETDEV_TX_OK; 146874aeea5SJeff Kirsher 147874aeea5SJeff Kirsher EFX_BUG_ON_PARANOID(tx_queue->write_count != tx_queue->insert_count); 148874aeea5SJeff Kirsher 149874aeea5SJeff Kirsher if (skb_shinfo(skb)->gso_size) 150874aeea5SJeff Kirsher return efx_enqueue_skb_tso(tx_queue, skb); 151874aeea5SJeff Kirsher 152874aeea5SJeff Kirsher /* Get size of the initial fragment */ 153874aeea5SJeff Kirsher len = skb_headlen(skb); 154874aeea5SJeff Kirsher 155874aeea5SJeff Kirsher /* Pad if necessary */ 156874aeea5SJeff Kirsher if (EFX_WORKAROUND_15592(efx) && skb->len <= 32) { 157874aeea5SJeff Kirsher EFX_BUG_ON_PARANOID(skb->data_len); 158874aeea5SJeff Kirsher len = 32 + 1; 159874aeea5SJeff Kirsher if (skb_pad(skb, len - skb->len)) 160874aeea5SJeff Kirsher return NETDEV_TX_OK; 161874aeea5SJeff Kirsher } 162874aeea5SJeff Kirsher 163874aeea5SJeff Kirsher fill_level = tx_queue->insert_count - tx_queue->old_read_count; 164874aeea5SJeff Kirsher q_space = efx->txq_entries - 1 - fill_level; 165874aeea5SJeff Kirsher 166874aeea5SJeff Kirsher /* Map for DMA. Use pci_map_single rather than pci_map_page 167874aeea5SJeff Kirsher * since this is more efficient on machines with sparse 168874aeea5SJeff Kirsher * memory. 169874aeea5SJeff Kirsher */ 170874aeea5SJeff Kirsher unmap_single = true; 171874aeea5SJeff Kirsher dma_addr = pci_map_single(pci_dev, skb->data, len, PCI_DMA_TODEVICE); 172874aeea5SJeff Kirsher 173874aeea5SJeff Kirsher /* Process all fragments */ 174874aeea5SJeff Kirsher while (1) { 175874aeea5SJeff Kirsher if (unlikely(pci_dma_mapping_error(pci_dev, dma_addr))) 176874aeea5SJeff Kirsher goto pci_err; 177874aeea5SJeff Kirsher 178874aeea5SJeff Kirsher /* Store fields for marking in the per-fragment final 179874aeea5SJeff Kirsher * descriptor */ 180874aeea5SJeff Kirsher unmap_len = len; 181874aeea5SJeff Kirsher unmap_addr = dma_addr; 182874aeea5SJeff Kirsher 183874aeea5SJeff Kirsher /* Add to TX queue, splitting across DMA boundaries */ 184874aeea5SJeff Kirsher do { 185874aeea5SJeff Kirsher if (unlikely(q_space-- <= 0)) { 186874aeea5SJeff Kirsher /* It might be that completions have 187874aeea5SJeff Kirsher * happened since the xmit path last 188874aeea5SJeff Kirsher * checked. Update the xmit path's 189874aeea5SJeff Kirsher * copy of read_count. 190874aeea5SJeff Kirsher */ 191874aeea5SJeff Kirsher netif_tx_stop_queue(tx_queue->core_txq); 192874aeea5SJeff Kirsher /* This memory barrier protects the 193874aeea5SJeff Kirsher * change of queue state from the access 194874aeea5SJeff Kirsher * of read_count. */ 195874aeea5SJeff Kirsher smp_mb(); 196874aeea5SJeff Kirsher tx_queue->old_read_count = 197874aeea5SJeff Kirsher ACCESS_ONCE(tx_queue->read_count); 198874aeea5SJeff Kirsher fill_level = (tx_queue->insert_count 199874aeea5SJeff Kirsher - tx_queue->old_read_count); 200874aeea5SJeff Kirsher q_space = efx->txq_entries - 1 - fill_level; 201874aeea5SJeff Kirsher if (unlikely(q_space-- <= 0)) { 202874aeea5SJeff Kirsher rc = NETDEV_TX_BUSY; 203874aeea5SJeff Kirsher goto unwind; 204874aeea5SJeff Kirsher } 205874aeea5SJeff Kirsher smp_mb(); 206874aeea5SJeff Kirsher if (likely(!efx->loopback_selftest)) 207874aeea5SJeff Kirsher netif_tx_start_queue( 208874aeea5SJeff Kirsher tx_queue->core_txq); 209874aeea5SJeff Kirsher } 210874aeea5SJeff Kirsher 211874aeea5SJeff Kirsher insert_ptr = tx_queue->insert_count & tx_queue->ptr_mask; 212874aeea5SJeff Kirsher buffer = &tx_queue->buffer[insert_ptr]; 213874aeea5SJeff Kirsher efx_tsoh_free(tx_queue, buffer); 214874aeea5SJeff Kirsher EFX_BUG_ON_PARANOID(buffer->tsoh); 215874aeea5SJeff Kirsher EFX_BUG_ON_PARANOID(buffer->skb); 216874aeea5SJeff Kirsher EFX_BUG_ON_PARANOID(buffer->len); 217874aeea5SJeff Kirsher EFX_BUG_ON_PARANOID(!buffer->continuation); 218874aeea5SJeff Kirsher EFX_BUG_ON_PARANOID(buffer->unmap_len); 219874aeea5SJeff Kirsher 220874aeea5SJeff Kirsher dma_len = efx_max_tx_len(efx, dma_addr); 221874aeea5SJeff Kirsher if (likely(dma_len >= len)) 222874aeea5SJeff Kirsher dma_len = len; 223874aeea5SJeff Kirsher 224874aeea5SJeff Kirsher /* Fill out per descriptor fields */ 225874aeea5SJeff Kirsher buffer->len = dma_len; 226874aeea5SJeff Kirsher buffer->dma_addr = dma_addr; 227874aeea5SJeff Kirsher len -= dma_len; 228874aeea5SJeff Kirsher dma_addr += dma_len; 229874aeea5SJeff Kirsher ++tx_queue->insert_count; 230874aeea5SJeff Kirsher } while (len); 231874aeea5SJeff Kirsher 232874aeea5SJeff Kirsher /* Transfer ownership of the unmapping to the final buffer */ 233874aeea5SJeff Kirsher buffer->unmap_single = unmap_single; 234874aeea5SJeff Kirsher buffer->unmap_len = unmap_len; 235874aeea5SJeff Kirsher unmap_len = 0; 236874aeea5SJeff Kirsher 237874aeea5SJeff Kirsher /* Get address and size of next fragment */ 238874aeea5SJeff Kirsher if (i >= skb_shinfo(skb)->nr_frags) 239874aeea5SJeff Kirsher break; 240874aeea5SJeff Kirsher fragment = &skb_shinfo(skb)->frags[i]; 241874aeea5SJeff Kirsher len = fragment->size; 242874aeea5SJeff Kirsher i++; 243874aeea5SJeff Kirsher /* Map for DMA */ 244874aeea5SJeff Kirsher unmap_single = false; 2454a22c4c9SIan Campbell dma_addr = skb_frag_dma_map(&pci_dev->dev, fragment, 0, len, 2465d6bcdfeSIan Campbell DMA_TO_DEVICE); 247874aeea5SJeff Kirsher } 248874aeea5SJeff Kirsher 249874aeea5SJeff Kirsher /* Transfer ownership of the skb to the final buffer */ 250874aeea5SJeff Kirsher buffer->skb = skb; 251874aeea5SJeff Kirsher buffer->continuation = false; 252874aeea5SJeff Kirsher 253874aeea5SJeff Kirsher /* Pass off to hardware */ 254874aeea5SJeff Kirsher efx_nic_push_buffers(tx_queue); 255874aeea5SJeff Kirsher 256874aeea5SJeff Kirsher return NETDEV_TX_OK; 257874aeea5SJeff Kirsher 258874aeea5SJeff Kirsher pci_err: 259874aeea5SJeff Kirsher netif_err(efx, tx_err, efx->net_dev, 260874aeea5SJeff Kirsher " TX queue %d could not map skb with %d bytes %d " 261874aeea5SJeff Kirsher "fragments for DMA\n", tx_queue->queue, skb->len, 262874aeea5SJeff Kirsher skb_shinfo(skb)->nr_frags + 1); 263874aeea5SJeff Kirsher 264874aeea5SJeff Kirsher /* Mark the packet as transmitted, and free the SKB ourselves */ 265874aeea5SJeff Kirsher dev_kfree_skb_any(skb); 266874aeea5SJeff Kirsher 267874aeea5SJeff Kirsher unwind: 268874aeea5SJeff Kirsher /* Work backwards until we hit the original insert pointer value */ 269874aeea5SJeff Kirsher while (tx_queue->insert_count != tx_queue->write_count) { 270874aeea5SJeff Kirsher --tx_queue->insert_count; 271874aeea5SJeff Kirsher insert_ptr = tx_queue->insert_count & tx_queue->ptr_mask; 272874aeea5SJeff Kirsher buffer = &tx_queue->buffer[insert_ptr]; 273874aeea5SJeff Kirsher efx_dequeue_buffer(tx_queue, buffer); 274874aeea5SJeff Kirsher buffer->len = 0; 275874aeea5SJeff Kirsher } 276874aeea5SJeff Kirsher 277874aeea5SJeff Kirsher /* Free the fragment we were mid-way through pushing */ 278874aeea5SJeff Kirsher if (unmap_len) { 279874aeea5SJeff Kirsher if (unmap_single) 280874aeea5SJeff Kirsher pci_unmap_single(pci_dev, unmap_addr, unmap_len, 281874aeea5SJeff Kirsher PCI_DMA_TODEVICE); 282874aeea5SJeff Kirsher else 283874aeea5SJeff Kirsher pci_unmap_page(pci_dev, unmap_addr, unmap_len, 284874aeea5SJeff Kirsher PCI_DMA_TODEVICE); 285874aeea5SJeff Kirsher } 286874aeea5SJeff Kirsher 287874aeea5SJeff Kirsher return rc; 288874aeea5SJeff Kirsher } 289874aeea5SJeff Kirsher 290874aeea5SJeff Kirsher /* Remove packets from the TX queue 291874aeea5SJeff Kirsher * 292874aeea5SJeff Kirsher * This removes packets from the TX queue, up to and including the 293874aeea5SJeff Kirsher * specified index. 294874aeea5SJeff Kirsher */ 295874aeea5SJeff Kirsher static void efx_dequeue_buffers(struct efx_tx_queue *tx_queue, 296874aeea5SJeff Kirsher unsigned int index) 297874aeea5SJeff Kirsher { 298874aeea5SJeff Kirsher struct efx_nic *efx = tx_queue->efx; 299874aeea5SJeff Kirsher unsigned int stop_index, read_ptr; 300874aeea5SJeff Kirsher 301874aeea5SJeff Kirsher stop_index = (index + 1) & tx_queue->ptr_mask; 302874aeea5SJeff Kirsher read_ptr = tx_queue->read_count & tx_queue->ptr_mask; 303874aeea5SJeff Kirsher 304874aeea5SJeff Kirsher while (read_ptr != stop_index) { 305874aeea5SJeff Kirsher struct efx_tx_buffer *buffer = &tx_queue->buffer[read_ptr]; 306874aeea5SJeff Kirsher if (unlikely(buffer->len == 0)) { 307874aeea5SJeff Kirsher netif_err(efx, tx_err, efx->net_dev, 308874aeea5SJeff Kirsher "TX queue %d spurious TX completion id %x\n", 309874aeea5SJeff Kirsher tx_queue->queue, read_ptr); 310874aeea5SJeff Kirsher efx_schedule_reset(efx, RESET_TYPE_TX_SKIP); 311874aeea5SJeff Kirsher return; 312874aeea5SJeff Kirsher } 313874aeea5SJeff Kirsher 314874aeea5SJeff Kirsher efx_dequeue_buffer(tx_queue, buffer); 315874aeea5SJeff Kirsher buffer->continuation = true; 316874aeea5SJeff Kirsher buffer->len = 0; 317874aeea5SJeff Kirsher 318874aeea5SJeff Kirsher ++tx_queue->read_count; 319874aeea5SJeff Kirsher read_ptr = tx_queue->read_count & tx_queue->ptr_mask; 320874aeea5SJeff Kirsher } 321874aeea5SJeff Kirsher } 322874aeea5SJeff Kirsher 323874aeea5SJeff Kirsher /* Initiate a packet transmission. We use one channel per CPU 324874aeea5SJeff Kirsher * (sharing when we have more CPUs than channels). On Falcon, the TX 325874aeea5SJeff Kirsher * completion events will be directed back to the CPU that transmitted 326874aeea5SJeff Kirsher * the packet, which should be cache-efficient. 327874aeea5SJeff Kirsher * 328874aeea5SJeff Kirsher * Context: non-blocking. 329874aeea5SJeff Kirsher * Note that returning anything other than NETDEV_TX_OK will cause the 330874aeea5SJeff Kirsher * OS to free the skb. 331874aeea5SJeff Kirsher */ 332874aeea5SJeff Kirsher netdev_tx_t efx_hard_start_xmit(struct sk_buff *skb, 333874aeea5SJeff Kirsher struct net_device *net_dev) 334874aeea5SJeff Kirsher { 335874aeea5SJeff Kirsher struct efx_nic *efx = netdev_priv(net_dev); 336874aeea5SJeff Kirsher struct efx_tx_queue *tx_queue; 337874aeea5SJeff Kirsher unsigned index, type; 338874aeea5SJeff Kirsher 339874aeea5SJeff Kirsher EFX_WARN_ON_PARANOID(!netif_device_present(net_dev)); 340874aeea5SJeff Kirsher 341874aeea5SJeff Kirsher index = skb_get_queue_mapping(skb); 342874aeea5SJeff Kirsher type = skb->ip_summed == CHECKSUM_PARTIAL ? EFX_TXQ_TYPE_OFFLOAD : 0; 343874aeea5SJeff Kirsher if (index >= efx->n_tx_channels) { 344874aeea5SJeff Kirsher index -= efx->n_tx_channels; 345874aeea5SJeff Kirsher type |= EFX_TXQ_TYPE_HIGHPRI; 346874aeea5SJeff Kirsher } 347874aeea5SJeff Kirsher tx_queue = efx_get_tx_queue(efx, index, type); 348874aeea5SJeff Kirsher 349874aeea5SJeff Kirsher return efx_enqueue_skb(tx_queue, skb); 350874aeea5SJeff Kirsher } 351874aeea5SJeff Kirsher 352874aeea5SJeff Kirsher void efx_init_tx_queue_core_txq(struct efx_tx_queue *tx_queue) 353874aeea5SJeff Kirsher { 354874aeea5SJeff Kirsher struct efx_nic *efx = tx_queue->efx; 355874aeea5SJeff Kirsher 356874aeea5SJeff Kirsher /* Must be inverse of queue lookup in efx_hard_start_xmit() */ 357874aeea5SJeff Kirsher tx_queue->core_txq = 358874aeea5SJeff Kirsher netdev_get_tx_queue(efx->net_dev, 359874aeea5SJeff Kirsher tx_queue->queue / EFX_TXQ_TYPES + 360874aeea5SJeff Kirsher ((tx_queue->queue & EFX_TXQ_TYPE_HIGHPRI) ? 361874aeea5SJeff Kirsher efx->n_tx_channels : 0)); 362874aeea5SJeff Kirsher } 363874aeea5SJeff Kirsher 364874aeea5SJeff Kirsher int efx_setup_tc(struct net_device *net_dev, u8 num_tc) 365874aeea5SJeff Kirsher { 366874aeea5SJeff Kirsher struct efx_nic *efx = netdev_priv(net_dev); 367874aeea5SJeff Kirsher struct efx_channel *channel; 368874aeea5SJeff Kirsher struct efx_tx_queue *tx_queue; 369874aeea5SJeff Kirsher unsigned tc; 370874aeea5SJeff Kirsher int rc; 371874aeea5SJeff Kirsher 372874aeea5SJeff Kirsher if (efx_nic_rev(efx) < EFX_REV_FALCON_B0 || num_tc > EFX_MAX_TX_TC) 373874aeea5SJeff Kirsher return -EINVAL; 374874aeea5SJeff Kirsher 375874aeea5SJeff Kirsher if (num_tc == net_dev->num_tc) 376874aeea5SJeff Kirsher return 0; 377874aeea5SJeff Kirsher 378874aeea5SJeff Kirsher for (tc = 0; tc < num_tc; tc++) { 379874aeea5SJeff Kirsher net_dev->tc_to_txq[tc].offset = tc * efx->n_tx_channels; 380874aeea5SJeff Kirsher net_dev->tc_to_txq[tc].count = efx->n_tx_channels; 381874aeea5SJeff Kirsher } 382874aeea5SJeff Kirsher 383874aeea5SJeff Kirsher if (num_tc > net_dev->num_tc) { 384874aeea5SJeff Kirsher /* Initialise high-priority queues as necessary */ 385874aeea5SJeff Kirsher efx_for_each_channel(channel, efx) { 386874aeea5SJeff Kirsher efx_for_each_possible_channel_tx_queue(tx_queue, 387874aeea5SJeff Kirsher channel) { 388874aeea5SJeff Kirsher if (!(tx_queue->queue & EFX_TXQ_TYPE_HIGHPRI)) 389874aeea5SJeff Kirsher continue; 390874aeea5SJeff Kirsher if (!tx_queue->buffer) { 391874aeea5SJeff Kirsher rc = efx_probe_tx_queue(tx_queue); 392874aeea5SJeff Kirsher if (rc) 393874aeea5SJeff Kirsher return rc; 394874aeea5SJeff Kirsher } 395874aeea5SJeff Kirsher if (!tx_queue->initialised) 396874aeea5SJeff Kirsher efx_init_tx_queue(tx_queue); 397874aeea5SJeff Kirsher efx_init_tx_queue_core_txq(tx_queue); 398874aeea5SJeff Kirsher } 399874aeea5SJeff Kirsher } 400874aeea5SJeff Kirsher } else { 401874aeea5SJeff Kirsher /* Reduce number of classes before number of queues */ 402874aeea5SJeff Kirsher net_dev->num_tc = num_tc; 403874aeea5SJeff Kirsher } 404874aeea5SJeff Kirsher 405874aeea5SJeff Kirsher rc = netif_set_real_num_tx_queues(net_dev, 406874aeea5SJeff Kirsher max_t(int, num_tc, 1) * 407874aeea5SJeff Kirsher efx->n_tx_channels); 408874aeea5SJeff Kirsher if (rc) 409874aeea5SJeff Kirsher return rc; 410874aeea5SJeff Kirsher 411874aeea5SJeff Kirsher /* Do not destroy high-priority queues when they become 412874aeea5SJeff Kirsher * unused. We would have to flush them first, and it is 413874aeea5SJeff Kirsher * fairly difficult to flush a subset of TX queues. Leave 414874aeea5SJeff Kirsher * it to efx_fini_channels(). 415874aeea5SJeff Kirsher */ 416874aeea5SJeff Kirsher 417874aeea5SJeff Kirsher net_dev->num_tc = num_tc; 418874aeea5SJeff Kirsher return 0; 419874aeea5SJeff Kirsher } 420874aeea5SJeff Kirsher 421874aeea5SJeff Kirsher void efx_xmit_done(struct efx_tx_queue *tx_queue, unsigned int index) 422874aeea5SJeff Kirsher { 423874aeea5SJeff Kirsher unsigned fill_level; 424874aeea5SJeff Kirsher struct efx_nic *efx = tx_queue->efx; 425874aeea5SJeff Kirsher 426874aeea5SJeff Kirsher EFX_BUG_ON_PARANOID(index > tx_queue->ptr_mask); 427874aeea5SJeff Kirsher 428874aeea5SJeff Kirsher efx_dequeue_buffers(tx_queue, index); 429874aeea5SJeff Kirsher 430874aeea5SJeff Kirsher /* See if we need to restart the netif queue. This barrier 431874aeea5SJeff Kirsher * separates the update of read_count from the test of the 432874aeea5SJeff Kirsher * queue state. */ 433874aeea5SJeff Kirsher smp_mb(); 434874aeea5SJeff Kirsher if (unlikely(netif_tx_queue_stopped(tx_queue->core_txq)) && 435874aeea5SJeff Kirsher likely(efx->port_enabled) && 436874aeea5SJeff Kirsher likely(netif_device_present(efx->net_dev))) { 437874aeea5SJeff Kirsher fill_level = tx_queue->insert_count - tx_queue->read_count; 438874aeea5SJeff Kirsher if (fill_level < EFX_TXQ_THRESHOLD(efx)) { 439874aeea5SJeff Kirsher EFX_BUG_ON_PARANOID(!efx_dev_registered(efx)); 440874aeea5SJeff Kirsher netif_tx_wake_queue(tx_queue->core_txq); 441874aeea5SJeff Kirsher } 442874aeea5SJeff Kirsher } 443874aeea5SJeff Kirsher 444874aeea5SJeff Kirsher /* Check whether the hardware queue is now empty */ 445874aeea5SJeff Kirsher if ((int)(tx_queue->read_count - tx_queue->old_write_count) >= 0) { 446874aeea5SJeff Kirsher tx_queue->old_write_count = ACCESS_ONCE(tx_queue->write_count); 447874aeea5SJeff Kirsher if (tx_queue->read_count == tx_queue->old_write_count) { 448874aeea5SJeff Kirsher smp_mb(); 449874aeea5SJeff Kirsher tx_queue->empty_read_count = 450874aeea5SJeff Kirsher tx_queue->read_count | EFX_EMPTY_COUNT_VALID; 451874aeea5SJeff Kirsher } 452874aeea5SJeff Kirsher } 453874aeea5SJeff Kirsher } 454874aeea5SJeff Kirsher 455874aeea5SJeff Kirsher int efx_probe_tx_queue(struct efx_tx_queue *tx_queue) 456874aeea5SJeff Kirsher { 457874aeea5SJeff Kirsher struct efx_nic *efx = tx_queue->efx; 458874aeea5SJeff Kirsher unsigned int entries; 459874aeea5SJeff Kirsher int i, rc; 460874aeea5SJeff Kirsher 461874aeea5SJeff Kirsher /* Create the smallest power-of-two aligned ring */ 462874aeea5SJeff Kirsher entries = max(roundup_pow_of_two(efx->txq_entries), EFX_MIN_DMAQ_SIZE); 463874aeea5SJeff Kirsher EFX_BUG_ON_PARANOID(entries > EFX_MAX_DMAQ_SIZE); 464874aeea5SJeff Kirsher tx_queue->ptr_mask = entries - 1; 465874aeea5SJeff Kirsher 466874aeea5SJeff Kirsher netif_dbg(efx, probe, efx->net_dev, 467874aeea5SJeff Kirsher "creating TX queue %d size %#x mask %#x\n", 468874aeea5SJeff Kirsher tx_queue->queue, efx->txq_entries, tx_queue->ptr_mask); 469874aeea5SJeff Kirsher 470874aeea5SJeff Kirsher /* Allocate software ring */ 471874aeea5SJeff Kirsher tx_queue->buffer = kzalloc(entries * sizeof(*tx_queue->buffer), 472874aeea5SJeff Kirsher GFP_KERNEL); 473874aeea5SJeff Kirsher if (!tx_queue->buffer) 474874aeea5SJeff Kirsher return -ENOMEM; 475874aeea5SJeff Kirsher for (i = 0; i <= tx_queue->ptr_mask; ++i) 476874aeea5SJeff Kirsher tx_queue->buffer[i].continuation = true; 477874aeea5SJeff Kirsher 478874aeea5SJeff Kirsher /* Allocate hardware ring */ 479874aeea5SJeff Kirsher rc = efx_nic_probe_tx(tx_queue); 480874aeea5SJeff Kirsher if (rc) 481874aeea5SJeff Kirsher goto fail; 482874aeea5SJeff Kirsher 483874aeea5SJeff Kirsher return 0; 484874aeea5SJeff Kirsher 485874aeea5SJeff Kirsher fail: 486874aeea5SJeff Kirsher kfree(tx_queue->buffer); 487874aeea5SJeff Kirsher tx_queue->buffer = NULL; 488874aeea5SJeff Kirsher return rc; 489874aeea5SJeff Kirsher } 490874aeea5SJeff Kirsher 491874aeea5SJeff Kirsher void efx_init_tx_queue(struct efx_tx_queue *tx_queue) 492874aeea5SJeff Kirsher { 493874aeea5SJeff Kirsher netif_dbg(tx_queue->efx, drv, tx_queue->efx->net_dev, 494874aeea5SJeff Kirsher "initialising TX queue %d\n", tx_queue->queue); 495874aeea5SJeff Kirsher 496874aeea5SJeff Kirsher tx_queue->insert_count = 0; 497874aeea5SJeff Kirsher tx_queue->write_count = 0; 498874aeea5SJeff Kirsher tx_queue->old_write_count = 0; 499874aeea5SJeff Kirsher tx_queue->read_count = 0; 500874aeea5SJeff Kirsher tx_queue->old_read_count = 0; 501874aeea5SJeff Kirsher tx_queue->empty_read_count = 0 | EFX_EMPTY_COUNT_VALID; 502874aeea5SJeff Kirsher 503874aeea5SJeff Kirsher /* Set up TX descriptor ring */ 504874aeea5SJeff Kirsher efx_nic_init_tx(tx_queue); 505874aeea5SJeff Kirsher 506874aeea5SJeff Kirsher tx_queue->initialised = true; 507874aeea5SJeff Kirsher } 508874aeea5SJeff Kirsher 509874aeea5SJeff Kirsher void efx_release_tx_buffers(struct efx_tx_queue *tx_queue) 510874aeea5SJeff Kirsher { 511874aeea5SJeff Kirsher struct efx_tx_buffer *buffer; 512874aeea5SJeff Kirsher 513874aeea5SJeff Kirsher if (!tx_queue->buffer) 514874aeea5SJeff Kirsher return; 515874aeea5SJeff Kirsher 516874aeea5SJeff Kirsher /* Free any buffers left in the ring */ 517874aeea5SJeff Kirsher while (tx_queue->read_count != tx_queue->write_count) { 518874aeea5SJeff Kirsher buffer = &tx_queue->buffer[tx_queue->read_count & tx_queue->ptr_mask]; 519874aeea5SJeff Kirsher efx_dequeue_buffer(tx_queue, buffer); 520874aeea5SJeff Kirsher buffer->continuation = true; 521874aeea5SJeff Kirsher buffer->len = 0; 522874aeea5SJeff Kirsher 523874aeea5SJeff Kirsher ++tx_queue->read_count; 524874aeea5SJeff Kirsher } 525874aeea5SJeff Kirsher } 526874aeea5SJeff Kirsher 527874aeea5SJeff Kirsher void efx_fini_tx_queue(struct efx_tx_queue *tx_queue) 528874aeea5SJeff Kirsher { 529874aeea5SJeff Kirsher if (!tx_queue->initialised) 530874aeea5SJeff Kirsher return; 531874aeea5SJeff Kirsher 532874aeea5SJeff Kirsher netif_dbg(tx_queue->efx, drv, tx_queue->efx->net_dev, 533874aeea5SJeff Kirsher "shutting down TX queue %d\n", tx_queue->queue); 534874aeea5SJeff Kirsher 535874aeea5SJeff Kirsher tx_queue->initialised = false; 536874aeea5SJeff Kirsher 537874aeea5SJeff Kirsher /* Flush TX queue, remove descriptor ring */ 538874aeea5SJeff Kirsher efx_nic_fini_tx(tx_queue); 539874aeea5SJeff Kirsher 540874aeea5SJeff Kirsher efx_release_tx_buffers(tx_queue); 541874aeea5SJeff Kirsher 542874aeea5SJeff Kirsher /* Free up TSO header cache */ 543874aeea5SJeff Kirsher efx_fini_tso(tx_queue); 544874aeea5SJeff Kirsher } 545874aeea5SJeff Kirsher 546874aeea5SJeff Kirsher void efx_remove_tx_queue(struct efx_tx_queue *tx_queue) 547874aeea5SJeff Kirsher { 548874aeea5SJeff Kirsher if (!tx_queue->buffer) 549874aeea5SJeff Kirsher return; 550874aeea5SJeff Kirsher 551874aeea5SJeff Kirsher netif_dbg(tx_queue->efx, drv, tx_queue->efx->net_dev, 552874aeea5SJeff Kirsher "destroying TX queue %d\n", tx_queue->queue); 553874aeea5SJeff Kirsher efx_nic_remove_tx(tx_queue); 554874aeea5SJeff Kirsher 555874aeea5SJeff Kirsher kfree(tx_queue->buffer); 556874aeea5SJeff Kirsher tx_queue->buffer = NULL; 557874aeea5SJeff Kirsher } 558874aeea5SJeff Kirsher 559874aeea5SJeff Kirsher 560874aeea5SJeff Kirsher /* Efx TCP segmentation acceleration. 561874aeea5SJeff Kirsher * 562874aeea5SJeff Kirsher * Why? Because by doing it here in the driver we can go significantly 563874aeea5SJeff Kirsher * faster than the GSO. 564874aeea5SJeff Kirsher * 565874aeea5SJeff Kirsher * Requires TX checksum offload support. 566874aeea5SJeff Kirsher */ 567874aeea5SJeff Kirsher 568874aeea5SJeff Kirsher /* Number of bytes inserted at the start of a TSO header buffer, 569874aeea5SJeff Kirsher * similar to NET_IP_ALIGN. 570874aeea5SJeff Kirsher */ 571874aeea5SJeff Kirsher #ifdef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS 572874aeea5SJeff Kirsher #define TSOH_OFFSET 0 573874aeea5SJeff Kirsher #else 574874aeea5SJeff Kirsher #define TSOH_OFFSET NET_IP_ALIGN 575874aeea5SJeff Kirsher #endif 576874aeea5SJeff Kirsher 577874aeea5SJeff Kirsher #define TSOH_BUFFER(tsoh) ((u8 *)(tsoh + 1) + TSOH_OFFSET) 578874aeea5SJeff Kirsher 579874aeea5SJeff Kirsher /* Total size of struct efx_tso_header, buffer and padding */ 580874aeea5SJeff Kirsher #define TSOH_SIZE(hdr_len) \ 581874aeea5SJeff Kirsher (sizeof(struct efx_tso_header) + TSOH_OFFSET + hdr_len) 582874aeea5SJeff Kirsher 583874aeea5SJeff Kirsher /* Size of blocks on free list. Larger blocks must be allocated from 584874aeea5SJeff Kirsher * the heap. 585874aeea5SJeff Kirsher */ 586874aeea5SJeff Kirsher #define TSOH_STD_SIZE 128 587874aeea5SJeff Kirsher 588874aeea5SJeff Kirsher #define PTR_DIFF(p1, p2) ((u8 *)(p1) - (u8 *)(p2)) 589874aeea5SJeff Kirsher #define ETH_HDR_LEN(skb) (skb_network_header(skb) - (skb)->data) 590874aeea5SJeff Kirsher #define SKB_TCP_OFF(skb) PTR_DIFF(tcp_hdr(skb), (skb)->data) 591874aeea5SJeff Kirsher #define SKB_IPV4_OFF(skb) PTR_DIFF(ip_hdr(skb), (skb)->data) 592874aeea5SJeff Kirsher #define SKB_IPV6_OFF(skb) PTR_DIFF(ipv6_hdr(skb), (skb)->data) 593874aeea5SJeff Kirsher 594874aeea5SJeff Kirsher /** 595874aeea5SJeff Kirsher * struct tso_state - TSO state for an SKB 596874aeea5SJeff Kirsher * @out_len: Remaining length in current segment 597874aeea5SJeff Kirsher * @seqnum: Current sequence number 598874aeea5SJeff Kirsher * @ipv4_id: Current IPv4 ID, host endian 599874aeea5SJeff Kirsher * @packet_space: Remaining space in current packet 600874aeea5SJeff Kirsher * @dma_addr: DMA address of current position 601874aeea5SJeff Kirsher * @in_len: Remaining length in current SKB fragment 602874aeea5SJeff Kirsher * @unmap_len: Length of SKB fragment 603874aeea5SJeff Kirsher * @unmap_addr: DMA address of SKB fragment 604874aeea5SJeff Kirsher * @unmap_single: DMA single vs page mapping flag 605874aeea5SJeff Kirsher * @protocol: Network protocol (after any VLAN header) 606874aeea5SJeff Kirsher * @header_len: Number of bytes of header 607874aeea5SJeff Kirsher * @full_packet_size: Number of bytes to put in each outgoing segment 608874aeea5SJeff Kirsher * 609874aeea5SJeff Kirsher * The state used during segmentation. It is put into this data structure 610874aeea5SJeff Kirsher * just to make it easy to pass into inline functions. 611874aeea5SJeff Kirsher */ 612874aeea5SJeff Kirsher struct tso_state { 613874aeea5SJeff Kirsher /* Output position */ 614874aeea5SJeff Kirsher unsigned out_len; 615874aeea5SJeff Kirsher unsigned seqnum; 616874aeea5SJeff Kirsher unsigned ipv4_id; 617874aeea5SJeff Kirsher unsigned packet_space; 618874aeea5SJeff Kirsher 619874aeea5SJeff Kirsher /* Input position */ 620874aeea5SJeff Kirsher dma_addr_t dma_addr; 621874aeea5SJeff Kirsher unsigned in_len; 622874aeea5SJeff Kirsher unsigned unmap_len; 623874aeea5SJeff Kirsher dma_addr_t unmap_addr; 624874aeea5SJeff Kirsher bool unmap_single; 625874aeea5SJeff Kirsher 626874aeea5SJeff Kirsher __be16 protocol; 627874aeea5SJeff Kirsher unsigned header_len; 628874aeea5SJeff Kirsher int full_packet_size; 629874aeea5SJeff Kirsher }; 630874aeea5SJeff Kirsher 631874aeea5SJeff Kirsher 632874aeea5SJeff Kirsher /* 633874aeea5SJeff Kirsher * Verify that our various assumptions about sk_buffs and the conditions 634874aeea5SJeff Kirsher * under which TSO will be attempted hold true. Return the protocol number. 635874aeea5SJeff Kirsher */ 636874aeea5SJeff Kirsher static __be16 efx_tso_check_protocol(struct sk_buff *skb) 637874aeea5SJeff Kirsher { 638874aeea5SJeff Kirsher __be16 protocol = skb->protocol; 639874aeea5SJeff Kirsher 640874aeea5SJeff Kirsher EFX_BUG_ON_PARANOID(((struct ethhdr *)skb->data)->h_proto != 641874aeea5SJeff Kirsher protocol); 642874aeea5SJeff Kirsher if (protocol == htons(ETH_P_8021Q)) { 643874aeea5SJeff Kirsher /* Find the encapsulated protocol; reset network header 644874aeea5SJeff Kirsher * and transport header based on that. */ 645874aeea5SJeff Kirsher struct vlan_ethhdr *veh = (struct vlan_ethhdr *)skb->data; 646874aeea5SJeff Kirsher protocol = veh->h_vlan_encapsulated_proto; 647874aeea5SJeff Kirsher skb_set_network_header(skb, sizeof(*veh)); 648874aeea5SJeff Kirsher if (protocol == htons(ETH_P_IP)) 649874aeea5SJeff Kirsher skb_set_transport_header(skb, sizeof(*veh) + 650874aeea5SJeff Kirsher 4 * ip_hdr(skb)->ihl); 651874aeea5SJeff Kirsher else if (protocol == htons(ETH_P_IPV6)) 652874aeea5SJeff Kirsher skb_set_transport_header(skb, sizeof(*veh) + 653874aeea5SJeff Kirsher sizeof(struct ipv6hdr)); 654874aeea5SJeff Kirsher } 655874aeea5SJeff Kirsher 656874aeea5SJeff Kirsher if (protocol == htons(ETH_P_IP)) { 657874aeea5SJeff Kirsher EFX_BUG_ON_PARANOID(ip_hdr(skb)->protocol != IPPROTO_TCP); 658874aeea5SJeff Kirsher } else { 659874aeea5SJeff Kirsher EFX_BUG_ON_PARANOID(protocol != htons(ETH_P_IPV6)); 660874aeea5SJeff Kirsher EFX_BUG_ON_PARANOID(ipv6_hdr(skb)->nexthdr != NEXTHDR_TCP); 661874aeea5SJeff Kirsher } 662874aeea5SJeff Kirsher EFX_BUG_ON_PARANOID((PTR_DIFF(tcp_hdr(skb), skb->data) 663874aeea5SJeff Kirsher + (tcp_hdr(skb)->doff << 2u)) > 664874aeea5SJeff Kirsher skb_headlen(skb)); 665874aeea5SJeff Kirsher 666874aeea5SJeff Kirsher return protocol; 667874aeea5SJeff Kirsher } 668874aeea5SJeff Kirsher 669874aeea5SJeff Kirsher 670874aeea5SJeff Kirsher /* 671874aeea5SJeff Kirsher * Allocate a page worth of efx_tso_header structures, and string them 672874aeea5SJeff Kirsher * into the tx_queue->tso_headers_free linked list. Return 0 or -ENOMEM. 673874aeea5SJeff Kirsher */ 674874aeea5SJeff Kirsher static int efx_tsoh_block_alloc(struct efx_tx_queue *tx_queue) 675874aeea5SJeff Kirsher { 676874aeea5SJeff Kirsher 677874aeea5SJeff Kirsher struct pci_dev *pci_dev = tx_queue->efx->pci_dev; 678874aeea5SJeff Kirsher struct efx_tso_header *tsoh; 679874aeea5SJeff Kirsher dma_addr_t dma_addr; 680874aeea5SJeff Kirsher u8 *base_kva, *kva; 681874aeea5SJeff Kirsher 682874aeea5SJeff Kirsher base_kva = pci_alloc_consistent(pci_dev, PAGE_SIZE, &dma_addr); 683874aeea5SJeff Kirsher if (base_kva == NULL) { 684874aeea5SJeff Kirsher netif_err(tx_queue->efx, tx_err, tx_queue->efx->net_dev, 685874aeea5SJeff Kirsher "Unable to allocate page for TSO headers\n"); 686874aeea5SJeff Kirsher return -ENOMEM; 687874aeea5SJeff Kirsher } 688874aeea5SJeff Kirsher 689874aeea5SJeff Kirsher /* pci_alloc_consistent() allocates pages. */ 690874aeea5SJeff Kirsher EFX_BUG_ON_PARANOID(dma_addr & (PAGE_SIZE - 1u)); 691874aeea5SJeff Kirsher 692874aeea5SJeff Kirsher for (kva = base_kva; kva < base_kva + PAGE_SIZE; kva += TSOH_STD_SIZE) { 693874aeea5SJeff Kirsher tsoh = (struct efx_tso_header *)kva; 694874aeea5SJeff Kirsher tsoh->dma_addr = dma_addr + (TSOH_BUFFER(tsoh) - base_kva); 695874aeea5SJeff Kirsher tsoh->next = tx_queue->tso_headers_free; 696874aeea5SJeff Kirsher tx_queue->tso_headers_free = tsoh; 697874aeea5SJeff Kirsher } 698874aeea5SJeff Kirsher 699874aeea5SJeff Kirsher return 0; 700874aeea5SJeff Kirsher } 701874aeea5SJeff Kirsher 702874aeea5SJeff Kirsher 703874aeea5SJeff Kirsher /* Free up a TSO header, and all others in the same page. */ 704874aeea5SJeff Kirsher static void efx_tsoh_block_free(struct efx_tx_queue *tx_queue, 705874aeea5SJeff Kirsher struct efx_tso_header *tsoh, 706874aeea5SJeff Kirsher struct pci_dev *pci_dev) 707874aeea5SJeff Kirsher { 708874aeea5SJeff Kirsher struct efx_tso_header **p; 709874aeea5SJeff Kirsher unsigned long base_kva; 710874aeea5SJeff Kirsher dma_addr_t base_dma; 711874aeea5SJeff Kirsher 712874aeea5SJeff Kirsher base_kva = (unsigned long)tsoh & PAGE_MASK; 713874aeea5SJeff Kirsher base_dma = tsoh->dma_addr & PAGE_MASK; 714874aeea5SJeff Kirsher 715874aeea5SJeff Kirsher p = &tx_queue->tso_headers_free; 716874aeea5SJeff Kirsher while (*p != NULL) { 717874aeea5SJeff Kirsher if (((unsigned long)*p & PAGE_MASK) == base_kva) 718874aeea5SJeff Kirsher *p = (*p)->next; 719874aeea5SJeff Kirsher else 720874aeea5SJeff Kirsher p = &(*p)->next; 721874aeea5SJeff Kirsher } 722874aeea5SJeff Kirsher 723874aeea5SJeff Kirsher pci_free_consistent(pci_dev, PAGE_SIZE, (void *)base_kva, base_dma); 724874aeea5SJeff Kirsher } 725874aeea5SJeff Kirsher 726874aeea5SJeff Kirsher static struct efx_tso_header * 727874aeea5SJeff Kirsher efx_tsoh_heap_alloc(struct efx_tx_queue *tx_queue, size_t header_len) 728874aeea5SJeff Kirsher { 729874aeea5SJeff Kirsher struct efx_tso_header *tsoh; 730874aeea5SJeff Kirsher 731874aeea5SJeff Kirsher tsoh = kmalloc(TSOH_SIZE(header_len), GFP_ATOMIC | GFP_DMA); 732874aeea5SJeff Kirsher if (unlikely(!tsoh)) 733874aeea5SJeff Kirsher return NULL; 734874aeea5SJeff Kirsher 735874aeea5SJeff Kirsher tsoh->dma_addr = pci_map_single(tx_queue->efx->pci_dev, 736874aeea5SJeff Kirsher TSOH_BUFFER(tsoh), header_len, 737874aeea5SJeff Kirsher PCI_DMA_TODEVICE); 738874aeea5SJeff Kirsher if (unlikely(pci_dma_mapping_error(tx_queue->efx->pci_dev, 739874aeea5SJeff Kirsher tsoh->dma_addr))) { 740874aeea5SJeff Kirsher kfree(tsoh); 741874aeea5SJeff Kirsher return NULL; 742874aeea5SJeff Kirsher } 743874aeea5SJeff Kirsher 744874aeea5SJeff Kirsher tsoh->unmap_len = header_len; 745874aeea5SJeff Kirsher return tsoh; 746874aeea5SJeff Kirsher } 747874aeea5SJeff Kirsher 748874aeea5SJeff Kirsher static void 749874aeea5SJeff Kirsher efx_tsoh_heap_free(struct efx_tx_queue *tx_queue, struct efx_tso_header *tsoh) 750874aeea5SJeff Kirsher { 751874aeea5SJeff Kirsher pci_unmap_single(tx_queue->efx->pci_dev, 752874aeea5SJeff Kirsher tsoh->dma_addr, tsoh->unmap_len, 753874aeea5SJeff Kirsher PCI_DMA_TODEVICE); 754874aeea5SJeff Kirsher kfree(tsoh); 755874aeea5SJeff Kirsher } 756874aeea5SJeff Kirsher 757874aeea5SJeff Kirsher /** 758874aeea5SJeff Kirsher * efx_tx_queue_insert - push descriptors onto the TX queue 759874aeea5SJeff Kirsher * @tx_queue: Efx TX queue 760874aeea5SJeff Kirsher * @dma_addr: DMA address of fragment 761874aeea5SJeff Kirsher * @len: Length of fragment 762874aeea5SJeff Kirsher * @final_buffer: The final buffer inserted into the queue 763874aeea5SJeff Kirsher * 764874aeea5SJeff Kirsher * Push descriptors onto the TX queue. Return 0 on success or 1 if 765874aeea5SJeff Kirsher * @tx_queue full. 766874aeea5SJeff Kirsher */ 767874aeea5SJeff Kirsher static int efx_tx_queue_insert(struct efx_tx_queue *tx_queue, 768874aeea5SJeff Kirsher dma_addr_t dma_addr, unsigned len, 769874aeea5SJeff Kirsher struct efx_tx_buffer **final_buffer) 770874aeea5SJeff Kirsher { 771874aeea5SJeff Kirsher struct efx_tx_buffer *buffer; 772874aeea5SJeff Kirsher struct efx_nic *efx = tx_queue->efx; 773874aeea5SJeff Kirsher unsigned dma_len, fill_level, insert_ptr; 774874aeea5SJeff Kirsher int q_space; 775874aeea5SJeff Kirsher 776874aeea5SJeff Kirsher EFX_BUG_ON_PARANOID(len <= 0); 777874aeea5SJeff Kirsher 778874aeea5SJeff Kirsher fill_level = tx_queue->insert_count - tx_queue->old_read_count; 779874aeea5SJeff Kirsher /* -1 as there is no way to represent all descriptors used */ 780874aeea5SJeff Kirsher q_space = efx->txq_entries - 1 - fill_level; 781874aeea5SJeff Kirsher 782874aeea5SJeff Kirsher while (1) { 783874aeea5SJeff Kirsher if (unlikely(q_space-- <= 0)) { 784874aeea5SJeff Kirsher /* It might be that completions have happened 785874aeea5SJeff Kirsher * since the xmit path last checked. Update 786874aeea5SJeff Kirsher * the xmit path's copy of read_count. 787874aeea5SJeff Kirsher */ 788874aeea5SJeff Kirsher netif_tx_stop_queue(tx_queue->core_txq); 789874aeea5SJeff Kirsher /* This memory barrier protects the change of 790874aeea5SJeff Kirsher * queue state from the access of read_count. */ 791874aeea5SJeff Kirsher smp_mb(); 792874aeea5SJeff Kirsher tx_queue->old_read_count = 793874aeea5SJeff Kirsher ACCESS_ONCE(tx_queue->read_count); 794874aeea5SJeff Kirsher fill_level = (tx_queue->insert_count 795874aeea5SJeff Kirsher - tx_queue->old_read_count); 796874aeea5SJeff Kirsher q_space = efx->txq_entries - 1 - fill_level; 797874aeea5SJeff Kirsher if (unlikely(q_space-- <= 0)) { 798874aeea5SJeff Kirsher *final_buffer = NULL; 799874aeea5SJeff Kirsher return 1; 800874aeea5SJeff Kirsher } 801874aeea5SJeff Kirsher smp_mb(); 802874aeea5SJeff Kirsher netif_tx_start_queue(tx_queue->core_txq); 803874aeea5SJeff Kirsher } 804874aeea5SJeff Kirsher 805874aeea5SJeff Kirsher insert_ptr = tx_queue->insert_count & tx_queue->ptr_mask; 806874aeea5SJeff Kirsher buffer = &tx_queue->buffer[insert_ptr]; 807874aeea5SJeff Kirsher ++tx_queue->insert_count; 808874aeea5SJeff Kirsher 809874aeea5SJeff Kirsher EFX_BUG_ON_PARANOID(tx_queue->insert_count - 810874aeea5SJeff Kirsher tx_queue->read_count >= 811874aeea5SJeff Kirsher efx->txq_entries); 812874aeea5SJeff Kirsher 813874aeea5SJeff Kirsher efx_tsoh_free(tx_queue, buffer); 814874aeea5SJeff Kirsher EFX_BUG_ON_PARANOID(buffer->len); 815874aeea5SJeff Kirsher EFX_BUG_ON_PARANOID(buffer->unmap_len); 816874aeea5SJeff Kirsher EFX_BUG_ON_PARANOID(buffer->skb); 817874aeea5SJeff Kirsher EFX_BUG_ON_PARANOID(!buffer->continuation); 818874aeea5SJeff Kirsher EFX_BUG_ON_PARANOID(buffer->tsoh); 819874aeea5SJeff Kirsher 820874aeea5SJeff Kirsher buffer->dma_addr = dma_addr; 821874aeea5SJeff Kirsher 822874aeea5SJeff Kirsher dma_len = efx_max_tx_len(efx, dma_addr); 823874aeea5SJeff Kirsher 824874aeea5SJeff Kirsher /* If there is enough space to send then do so */ 825874aeea5SJeff Kirsher if (dma_len >= len) 826874aeea5SJeff Kirsher break; 827874aeea5SJeff Kirsher 828874aeea5SJeff Kirsher buffer->len = dma_len; /* Don't set the other members */ 829874aeea5SJeff Kirsher dma_addr += dma_len; 830874aeea5SJeff Kirsher len -= dma_len; 831874aeea5SJeff Kirsher } 832874aeea5SJeff Kirsher 833874aeea5SJeff Kirsher EFX_BUG_ON_PARANOID(!len); 834874aeea5SJeff Kirsher buffer->len = len; 835874aeea5SJeff Kirsher *final_buffer = buffer; 836874aeea5SJeff Kirsher return 0; 837874aeea5SJeff Kirsher } 838874aeea5SJeff Kirsher 839874aeea5SJeff Kirsher 840874aeea5SJeff Kirsher /* 841874aeea5SJeff Kirsher * Put a TSO header into the TX queue. 842874aeea5SJeff Kirsher * 843874aeea5SJeff Kirsher * This is special-cased because we know that it is small enough to fit in 844874aeea5SJeff Kirsher * a single fragment, and we know it doesn't cross a page boundary. It 845874aeea5SJeff Kirsher * also allows us to not worry about end-of-packet etc. 846874aeea5SJeff Kirsher */ 847874aeea5SJeff Kirsher static void efx_tso_put_header(struct efx_tx_queue *tx_queue, 848874aeea5SJeff Kirsher struct efx_tso_header *tsoh, unsigned len) 849874aeea5SJeff Kirsher { 850874aeea5SJeff Kirsher struct efx_tx_buffer *buffer; 851874aeea5SJeff Kirsher 852874aeea5SJeff Kirsher buffer = &tx_queue->buffer[tx_queue->insert_count & tx_queue->ptr_mask]; 853874aeea5SJeff Kirsher efx_tsoh_free(tx_queue, buffer); 854874aeea5SJeff Kirsher EFX_BUG_ON_PARANOID(buffer->len); 855874aeea5SJeff Kirsher EFX_BUG_ON_PARANOID(buffer->unmap_len); 856874aeea5SJeff Kirsher EFX_BUG_ON_PARANOID(buffer->skb); 857874aeea5SJeff Kirsher EFX_BUG_ON_PARANOID(!buffer->continuation); 858874aeea5SJeff Kirsher EFX_BUG_ON_PARANOID(buffer->tsoh); 859874aeea5SJeff Kirsher buffer->len = len; 860874aeea5SJeff Kirsher buffer->dma_addr = tsoh->dma_addr; 861874aeea5SJeff Kirsher buffer->tsoh = tsoh; 862874aeea5SJeff Kirsher 863874aeea5SJeff Kirsher ++tx_queue->insert_count; 864874aeea5SJeff Kirsher } 865874aeea5SJeff Kirsher 866874aeea5SJeff Kirsher 867874aeea5SJeff Kirsher /* Remove descriptors put into a tx_queue. */ 868874aeea5SJeff Kirsher static void efx_enqueue_unwind(struct efx_tx_queue *tx_queue) 869874aeea5SJeff Kirsher { 870874aeea5SJeff Kirsher struct efx_tx_buffer *buffer; 871874aeea5SJeff Kirsher dma_addr_t unmap_addr; 872874aeea5SJeff Kirsher 873874aeea5SJeff Kirsher /* Work backwards until we hit the original insert pointer value */ 874874aeea5SJeff Kirsher while (tx_queue->insert_count != tx_queue->write_count) { 875874aeea5SJeff Kirsher --tx_queue->insert_count; 876874aeea5SJeff Kirsher buffer = &tx_queue->buffer[tx_queue->insert_count & 877874aeea5SJeff Kirsher tx_queue->ptr_mask]; 878874aeea5SJeff Kirsher efx_tsoh_free(tx_queue, buffer); 879874aeea5SJeff Kirsher EFX_BUG_ON_PARANOID(buffer->skb); 880874aeea5SJeff Kirsher if (buffer->unmap_len) { 881874aeea5SJeff Kirsher unmap_addr = (buffer->dma_addr + buffer->len - 882874aeea5SJeff Kirsher buffer->unmap_len); 883874aeea5SJeff Kirsher if (buffer->unmap_single) 884874aeea5SJeff Kirsher pci_unmap_single(tx_queue->efx->pci_dev, 885874aeea5SJeff Kirsher unmap_addr, buffer->unmap_len, 886874aeea5SJeff Kirsher PCI_DMA_TODEVICE); 887874aeea5SJeff Kirsher else 888874aeea5SJeff Kirsher pci_unmap_page(tx_queue->efx->pci_dev, 889874aeea5SJeff Kirsher unmap_addr, buffer->unmap_len, 890874aeea5SJeff Kirsher PCI_DMA_TODEVICE); 891874aeea5SJeff Kirsher buffer->unmap_len = 0; 892874aeea5SJeff Kirsher } 893874aeea5SJeff Kirsher buffer->len = 0; 894874aeea5SJeff Kirsher buffer->continuation = true; 895874aeea5SJeff Kirsher } 896874aeea5SJeff Kirsher } 897874aeea5SJeff Kirsher 898874aeea5SJeff Kirsher 899874aeea5SJeff Kirsher /* Parse the SKB header and initialise state. */ 900874aeea5SJeff Kirsher static void tso_start(struct tso_state *st, const struct sk_buff *skb) 901874aeea5SJeff Kirsher { 902874aeea5SJeff Kirsher /* All ethernet/IP/TCP headers combined size is TCP header size 903874aeea5SJeff Kirsher * plus offset of TCP header relative to start of packet. 904874aeea5SJeff Kirsher */ 905874aeea5SJeff Kirsher st->header_len = ((tcp_hdr(skb)->doff << 2u) 906874aeea5SJeff Kirsher + PTR_DIFF(tcp_hdr(skb), skb->data)); 907874aeea5SJeff Kirsher st->full_packet_size = st->header_len + skb_shinfo(skb)->gso_size; 908874aeea5SJeff Kirsher 909874aeea5SJeff Kirsher if (st->protocol == htons(ETH_P_IP)) 910874aeea5SJeff Kirsher st->ipv4_id = ntohs(ip_hdr(skb)->id); 911874aeea5SJeff Kirsher else 912874aeea5SJeff Kirsher st->ipv4_id = 0; 913874aeea5SJeff Kirsher st->seqnum = ntohl(tcp_hdr(skb)->seq); 914874aeea5SJeff Kirsher 915874aeea5SJeff Kirsher EFX_BUG_ON_PARANOID(tcp_hdr(skb)->urg); 916874aeea5SJeff Kirsher EFX_BUG_ON_PARANOID(tcp_hdr(skb)->syn); 917874aeea5SJeff Kirsher EFX_BUG_ON_PARANOID(tcp_hdr(skb)->rst); 918874aeea5SJeff Kirsher 919874aeea5SJeff Kirsher st->packet_space = st->full_packet_size; 920874aeea5SJeff Kirsher st->out_len = skb->len - st->header_len; 921874aeea5SJeff Kirsher st->unmap_len = 0; 922874aeea5SJeff Kirsher st->unmap_single = false; 923874aeea5SJeff Kirsher } 924874aeea5SJeff Kirsher 925874aeea5SJeff Kirsher static int tso_get_fragment(struct tso_state *st, struct efx_nic *efx, 926874aeea5SJeff Kirsher skb_frag_t *frag) 927874aeea5SJeff Kirsher { 9284a22c4c9SIan Campbell st->unmap_addr = skb_frag_dma_map(&efx->pci_dev->dev, frag, 0, 9295d6bcdfeSIan Campbell frag->size, DMA_TO_DEVICE); 9305d6bcdfeSIan Campbell if (likely(!dma_mapping_error(&efx->pci_dev->dev, st->unmap_addr))) { 931874aeea5SJeff Kirsher st->unmap_single = false; 932874aeea5SJeff Kirsher st->unmap_len = frag->size; 933874aeea5SJeff Kirsher st->in_len = frag->size; 934874aeea5SJeff Kirsher st->dma_addr = st->unmap_addr; 935874aeea5SJeff Kirsher return 0; 936874aeea5SJeff Kirsher } 937874aeea5SJeff Kirsher return -ENOMEM; 938874aeea5SJeff Kirsher } 939874aeea5SJeff Kirsher 940874aeea5SJeff Kirsher static int tso_get_head_fragment(struct tso_state *st, struct efx_nic *efx, 941874aeea5SJeff Kirsher const struct sk_buff *skb) 942874aeea5SJeff Kirsher { 943874aeea5SJeff Kirsher int hl = st->header_len; 944874aeea5SJeff Kirsher int len = skb_headlen(skb) - hl; 945874aeea5SJeff Kirsher 946874aeea5SJeff Kirsher st->unmap_addr = pci_map_single(efx->pci_dev, skb->data + hl, 947874aeea5SJeff Kirsher len, PCI_DMA_TODEVICE); 948874aeea5SJeff Kirsher if (likely(!pci_dma_mapping_error(efx->pci_dev, st->unmap_addr))) { 949874aeea5SJeff Kirsher st->unmap_single = true; 950874aeea5SJeff Kirsher st->unmap_len = len; 951874aeea5SJeff Kirsher st->in_len = len; 952874aeea5SJeff Kirsher st->dma_addr = st->unmap_addr; 953874aeea5SJeff Kirsher return 0; 954874aeea5SJeff Kirsher } 955874aeea5SJeff Kirsher return -ENOMEM; 956874aeea5SJeff Kirsher } 957874aeea5SJeff Kirsher 958874aeea5SJeff Kirsher 959874aeea5SJeff Kirsher /** 960874aeea5SJeff Kirsher * tso_fill_packet_with_fragment - form descriptors for the current fragment 961874aeea5SJeff Kirsher * @tx_queue: Efx TX queue 962874aeea5SJeff Kirsher * @skb: Socket buffer 963874aeea5SJeff Kirsher * @st: TSO state 964874aeea5SJeff Kirsher * 965874aeea5SJeff Kirsher * Form descriptors for the current fragment, until we reach the end 966874aeea5SJeff Kirsher * of fragment or end-of-packet. Return 0 on success, 1 if not enough 967874aeea5SJeff Kirsher * space in @tx_queue. 968874aeea5SJeff Kirsher */ 969874aeea5SJeff Kirsher static int tso_fill_packet_with_fragment(struct efx_tx_queue *tx_queue, 970874aeea5SJeff Kirsher const struct sk_buff *skb, 971874aeea5SJeff Kirsher struct tso_state *st) 972874aeea5SJeff Kirsher { 973874aeea5SJeff Kirsher struct efx_tx_buffer *buffer; 974874aeea5SJeff Kirsher int n, end_of_packet, rc; 975874aeea5SJeff Kirsher 976874aeea5SJeff Kirsher if (st->in_len == 0) 977874aeea5SJeff Kirsher return 0; 978874aeea5SJeff Kirsher if (st->packet_space == 0) 979874aeea5SJeff Kirsher return 0; 980874aeea5SJeff Kirsher 981874aeea5SJeff Kirsher EFX_BUG_ON_PARANOID(st->in_len <= 0); 982874aeea5SJeff Kirsher EFX_BUG_ON_PARANOID(st->packet_space <= 0); 983874aeea5SJeff Kirsher 984874aeea5SJeff Kirsher n = min(st->in_len, st->packet_space); 985874aeea5SJeff Kirsher 986874aeea5SJeff Kirsher st->packet_space -= n; 987874aeea5SJeff Kirsher st->out_len -= n; 988874aeea5SJeff Kirsher st->in_len -= n; 989874aeea5SJeff Kirsher 990874aeea5SJeff Kirsher rc = efx_tx_queue_insert(tx_queue, st->dma_addr, n, &buffer); 991874aeea5SJeff Kirsher if (likely(rc == 0)) { 992874aeea5SJeff Kirsher if (st->out_len == 0) 993874aeea5SJeff Kirsher /* Transfer ownership of the skb */ 994874aeea5SJeff Kirsher buffer->skb = skb; 995874aeea5SJeff Kirsher 996874aeea5SJeff Kirsher end_of_packet = st->out_len == 0 || st->packet_space == 0; 997874aeea5SJeff Kirsher buffer->continuation = !end_of_packet; 998874aeea5SJeff Kirsher 999874aeea5SJeff Kirsher if (st->in_len == 0) { 1000874aeea5SJeff Kirsher /* Transfer ownership of the pci mapping */ 1001874aeea5SJeff Kirsher buffer->unmap_len = st->unmap_len; 1002874aeea5SJeff Kirsher buffer->unmap_single = st->unmap_single; 1003874aeea5SJeff Kirsher st->unmap_len = 0; 1004874aeea5SJeff Kirsher } 1005874aeea5SJeff Kirsher } 1006874aeea5SJeff Kirsher 1007874aeea5SJeff Kirsher st->dma_addr += n; 1008874aeea5SJeff Kirsher return rc; 1009874aeea5SJeff Kirsher } 1010874aeea5SJeff Kirsher 1011874aeea5SJeff Kirsher 1012874aeea5SJeff Kirsher /** 1013874aeea5SJeff Kirsher * tso_start_new_packet - generate a new header and prepare for the new packet 1014874aeea5SJeff Kirsher * @tx_queue: Efx TX queue 1015874aeea5SJeff Kirsher * @skb: Socket buffer 1016874aeea5SJeff Kirsher * @st: TSO state 1017874aeea5SJeff Kirsher * 1018874aeea5SJeff Kirsher * Generate a new header and prepare for the new packet. Return 0 on 1019874aeea5SJeff Kirsher * success, or -1 if failed to alloc header. 1020874aeea5SJeff Kirsher */ 1021874aeea5SJeff Kirsher static int tso_start_new_packet(struct efx_tx_queue *tx_queue, 1022874aeea5SJeff Kirsher const struct sk_buff *skb, 1023874aeea5SJeff Kirsher struct tso_state *st) 1024874aeea5SJeff Kirsher { 1025874aeea5SJeff Kirsher struct efx_tso_header *tsoh; 1026874aeea5SJeff Kirsher struct tcphdr *tsoh_th; 1027874aeea5SJeff Kirsher unsigned ip_length; 1028874aeea5SJeff Kirsher u8 *header; 1029874aeea5SJeff Kirsher 1030874aeea5SJeff Kirsher /* Allocate a DMA-mapped header buffer. */ 1031874aeea5SJeff Kirsher if (likely(TSOH_SIZE(st->header_len) <= TSOH_STD_SIZE)) { 1032874aeea5SJeff Kirsher if (tx_queue->tso_headers_free == NULL) { 1033874aeea5SJeff Kirsher if (efx_tsoh_block_alloc(tx_queue)) 1034874aeea5SJeff Kirsher return -1; 1035874aeea5SJeff Kirsher } 1036874aeea5SJeff Kirsher EFX_BUG_ON_PARANOID(!tx_queue->tso_headers_free); 1037874aeea5SJeff Kirsher tsoh = tx_queue->tso_headers_free; 1038874aeea5SJeff Kirsher tx_queue->tso_headers_free = tsoh->next; 1039874aeea5SJeff Kirsher tsoh->unmap_len = 0; 1040874aeea5SJeff Kirsher } else { 1041874aeea5SJeff Kirsher tx_queue->tso_long_headers++; 1042874aeea5SJeff Kirsher tsoh = efx_tsoh_heap_alloc(tx_queue, st->header_len); 1043874aeea5SJeff Kirsher if (unlikely(!tsoh)) 1044874aeea5SJeff Kirsher return -1; 1045874aeea5SJeff Kirsher } 1046874aeea5SJeff Kirsher 1047874aeea5SJeff Kirsher header = TSOH_BUFFER(tsoh); 1048874aeea5SJeff Kirsher tsoh_th = (struct tcphdr *)(header + SKB_TCP_OFF(skb)); 1049874aeea5SJeff Kirsher 1050874aeea5SJeff Kirsher /* Copy and update the headers. */ 1051874aeea5SJeff Kirsher memcpy(header, skb->data, st->header_len); 1052874aeea5SJeff Kirsher 1053874aeea5SJeff Kirsher tsoh_th->seq = htonl(st->seqnum); 1054874aeea5SJeff Kirsher st->seqnum += skb_shinfo(skb)->gso_size; 1055874aeea5SJeff Kirsher if (st->out_len > skb_shinfo(skb)->gso_size) { 1056874aeea5SJeff Kirsher /* This packet will not finish the TSO burst. */ 1057874aeea5SJeff Kirsher ip_length = st->full_packet_size - ETH_HDR_LEN(skb); 1058874aeea5SJeff Kirsher tsoh_th->fin = 0; 1059874aeea5SJeff Kirsher tsoh_th->psh = 0; 1060874aeea5SJeff Kirsher } else { 1061874aeea5SJeff Kirsher /* This packet will be the last in the TSO burst. */ 1062874aeea5SJeff Kirsher ip_length = st->header_len - ETH_HDR_LEN(skb) + st->out_len; 1063874aeea5SJeff Kirsher tsoh_th->fin = tcp_hdr(skb)->fin; 1064874aeea5SJeff Kirsher tsoh_th->psh = tcp_hdr(skb)->psh; 1065874aeea5SJeff Kirsher } 1066874aeea5SJeff Kirsher 1067874aeea5SJeff Kirsher if (st->protocol == htons(ETH_P_IP)) { 1068874aeea5SJeff Kirsher struct iphdr *tsoh_iph = 1069874aeea5SJeff Kirsher (struct iphdr *)(header + SKB_IPV4_OFF(skb)); 1070874aeea5SJeff Kirsher 1071874aeea5SJeff Kirsher tsoh_iph->tot_len = htons(ip_length); 1072874aeea5SJeff Kirsher 1073874aeea5SJeff Kirsher /* Linux leaves suitable gaps in the IP ID space for us to fill. */ 1074874aeea5SJeff Kirsher tsoh_iph->id = htons(st->ipv4_id); 1075874aeea5SJeff Kirsher st->ipv4_id++; 1076874aeea5SJeff Kirsher } else { 1077874aeea5SJeff Kirsher struct ipv6hdr *tsoh_iph = 1078874aeea5SJeff Kirsher (struct ipv6hdr *)(header + SKB_IPV6_OFF(skb)); 1079874aeea5SJeff Kirsher 1080874aeea5SJeff Kirsher tsoh_iph->payload_len = htons(ip_length - sizeof(*tsoh_iph)); 1081874aeea5SJeff Kirsher } 1082874aeea5SJeff Kirsher 1083874aeea5SJeff Kirsher st->packet_space = skb_shinfo(skb)->gso_size; 1084874aeea5SJeff Kirsher ++tx_queue->tso_packets; 1085874aeea5SJeff Kirsher 1086874aeea5SJeff Kirsher /* Form a descriptor for this header. */ 1087874aeea5SJeff Kirsher efx_tso_put_header(tx_queue, tsoh, st->header_len); 1088874aeea5SJeff Kirsher 1089874aeea5SJeff Kirsher return 0; 1090874aeea5SJeff Kirsher } 1091874aeea5SJeff Kirsher 1092874aeea5SJeff Kirsher 1093874aeea5SJeff Kirsher /** 1094874aeea5SJeff Kirsher * efx_enqueue_skb_tso - segment and transmit a TSO socket buffer 1095874aeea5SJeff Kirsher * @tx_queue: Efx TX queue 1096874aeea5SJeff Kirsher * @skb: Socket buffer 1097874aeea5SJeff Kirsher * 1098874aeea5SJeff Kirsher * Context: You must hold netif_tx_lock() to call this function. 1099874aeea5SJeff Kirsher * 1100874aeea5SJeff Kirsher * Add socket buffer @skb to @tx_queue, doing TSO or return != 0 if 1101874aeea5SJeff Kirsher * @skb was not enqueued. In all cases @skb is consumed. Return 1102874aeea5SJeff Kirsher * %NETDEV_TX_OK or %NETDEV_TX_BUSY. 1103874aeea5SJeff Kirsher */ 1104874aeea5SJeff Kirsher static int efx_enqueue_skb_tso(struct efx_tx_queue *tx_queue, 1105874aeea5SJeff Kirsher struct sk_buff *skb) 1106874aeea5SJeff Kirsher { 1107874aeea5SJeff Kirsher struct efx_nic *efx = tx_queue->efx; 1108874aeea5SJeff Kirsher int frag_i, rc, rc2 = NETDEV_TX_OK; 1109874aeea5SJeff Kirsher struct tso_state state; 1110874aeea5SJeff Kirsher 1111874aeea5SJeff Kirsher /* Find the packet protocol and sanity-check it */ 1112874aeea5SJeff Kirsher state.protocol = efx_tso_check_protocol(skb); 1113874aeea5SJeff Kirsher 1114874aeea5SJeff Kirsher EFX_BUG_ON_PARANOID(tx_queue->write_count != tx_queue->insert_count); 1115874aeea5SJeff Kirsher 1116874aeea5SJeff Kirsher tso_start(&state, skb); 1117874aeea5SJeff Kirsher 1118874aeea5SJeff Kirsher /* Assume that skb header area contains exactly the headers, and 1119874aeea5SJeff Kirsher * all payload is in the frag list. 1120874aeea5SJeff Kirsher */ 1121874aeea5SJeff Kirsher if (skb_headlen(skb) == state.header_len) { 1122874aeea5SJeff Kirsher /* Grab the first payload fragment. */ 1123874aeea5SJeff Kirsher EFX_BUG_ON_PARANOID(skb_shinfo(skb)->nr_frags < 1); 1124874aeea5SJeff Kirsher frag_i = 0; 1125874aeea5SJeff Kirsher rc = tso_get_fragment(&state, efx, 1126874aeea5SJeff Kirsher skb_shinfo(skb)->frags + frag_i); 1127874aeea5SJeff Kirsher if (rc) 1128874aeea5SJeff Kirsher goto mem_err; 1129874aeea5SJeff Kirsher } else { 1130874aeea5SJeff Kirsher rc = tso_get_head_fragment(&state, efx, skb); 1131874aeea5SJeff Kirsher if (rc) 1132874aeea5SJeff Kirsher goto mem_err; 1133874aeea5SJeff Kirsher frag_i = -1; 1134874aeea5SJeff Kirsher } 1135874aeea5SJeff Kirsher 1136874aeea5SJeff Kirsher if (tso_start_new_packet(tx_queue, skb, &state) < 0) 1137874aeea5SJeff Kirsher goto mem_err; 1138874aeea5SJeff Kirsher 1139874aeea5SJeff Kirsher while (1) { 1140874aeea5SJeff Kirsher rc = tso_fill_packet_with_fragment(tx_queue, skb, &state); 1141874aeea5SJeff Kirsher if (unlikely(rc)) { 1142874aeea5SJeff Kirsher rc2 = NETDEV_TX_BUSY; 1143874aeea5SJeff Kirsher goto unwind; 1144874aeea5SJeff Kirsher } 1145874aeea5SJeff Kirsher 1146874aeea5SJeff Kirsher /* Move onto the next fragment? */ 1147874aeea5SJeff Kirsher if (state.in_len == 0) { 1148874aeea5SJeff Kirsher if (++frag_i >= skb_shinfo(skb)->nr_frags) 1149874aeea5SJeff Kirsher /* End of payload reached. */ 1150874aeea5SJeff Kirsher break; 1151874aeea5SJeff Kirsher rc = tso_get_fragment(&state, efx, 1152874aeea5SJeff Kirsher skb_shinfo(skb)->frags + frag_i); 1153874aeea5SJeff Kirsher if (rc) 1154874aeea5SJeff Kirsher goto mem_err; 1155874aeea5SJeff Kirsher } 1156874aeea5SJeff Kirsher 1157874aeea5SJeff Kirsher /* Start at new packet? */ 1158874aeea5SJeff Kirsher if (state.packet_space == 0 && 1159874aeea5SJeff Kirsher tso_start_new_packet(tx_queue, skb, &state) < 0) 1160874aeea5SJeff Kirsher goto mem_err; 1161874aeea5SJeff Kirsher } 1162874aeea5SJeff Kirsher 1163874aeea5SJeff Kirsher /* Pass off to hardware */ 1164874aeea5SJeff Kirsher efx_nic_push_buffers(tx_queue); 1165874aeea5SJeff Kirsher 1166874aeea5SJeff Kirsher tx_queue->tso_bursts++; 1167874aeea5SJeff Kirsher return NETDEV_TX_OK; 1168874aeea5SJeff Kirsher 1169874aeea5SJeff Kirsher mem_err: 1170874aeea5SJeff Kirsher netif_err(efx, tx_err, efx->net_dev, 1171874aeea5SJeff Kirsher "Out of memory for TSO headers, or PCI mapping error\n"); 1172874aeea5SJeff Kirsher dev_kfree_skb_any(skb); 1173874aeea5SJeff Kirsher 1174874aeea5SJeff Kirsher unwind: 1175874aeea5SJeff Kirsher /* Free the DMA mapping we were in the process of writing out */ 1176874aeea5SJeff Kirsher if (state.unmap_len) { 1177874aeea5SJeff Kirsher if (state.unmap_single) 1178874aeea5SJeff Kirsher pci_unmap_single(efx->pci_dev, state.unmap_addr, 1179874aeea5SJeff Kirsher state.unmap_len, PCI_DMA_TODEVICE); 1180874aeea5SJeff Kirsher else 1181874aeea5SJeff Kirsher pci_unmap_page(efx->pci_dev, state.unmap_addr, 1182874aeea5SJeff Kirsher state.unmap_len, PCI_DMA_TODEVICE); 1183874aeea5SJeff Kirsher } 1184874aeea5SJeff Kirsher 1185874aeea5SJeff Kirsher efx_enqueue_unwind(tx_queue); 1186874aeea5SJeff Kirsher return rc2; 1187874aeea5SJeff Kirsher } 1188874aeea5SJeff Kirsher 1189874aeea5SJeff Kirsher 1190874aeea5SJeff Kirsher /* 1191874aeea5SJeff Kirsher * Free up all TSO datastructures associated with tx_queue. This 1192874aeea5SJeff Kirsher * routine should be called only once the tx_queue is both empty and 1193874aeea5SJeff Kirsher * will no longer be used. 1194874aeea5SJeff Kirsher */ 1195874aeea5SJeff Kirsher static void efx_fini_tso(struct efx_tx_queue *tx_queue) 1196874aeea5SJeff Kirsher { 1197874aeea5SJeff Kirsher unsigned i; 1198874aeea5SJeff Kirsher 1199874aeea5SJeff Kirsher if (tx_queue->buffer) { 1200874aeea5SJeff Kirsher for (i = 0; i <= tx_queue->ptr_mask; ++i) 1201874aeea5SJeff Kirsher efx_tsoh_free(tx_queue, &tx_queue->buffer[i]); 1202874aeea5SJeff Kirsher } 1203874aeea5SJeff Kirsher 1204874aeea5SJeff Kirsher while (tx_queue->tso_headers_free != NULL) 1205874aeea5SJeff Kirsher efx_tsoh_block_free(tx_queue, tx_queue->tso_headers_free, 1206874aeea5SJeff Kirsher tx_queue->efx->pci_dev); 1207874aeea5SJeff Kirsher } 1208