diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2016-12-12 18:54:15 +0300 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2016-12-12 18:54:15 +0300 |
commit | ce38aa9cbed3d109355b0169b520362c409c0541 (patch) | |
tree | 621511c34edd22ac30ca12f78f0d478245b4ccd7 /drivers/net/ethernet/sfc/tx_tso.c | |
parent | 69973b830859bc6529a7a0468ba0d80ee5117826 (diff) | |
parent | d84701ecbcd6ad63faa7a9c18ad670d1c4d561c0 (diff) | |
download | linux-ce38aa9cbed3d109355b0169b520362c409c0541.tar.xz |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller:
1) Platform regulatory domain support for ath10k, from Bartosz
Markowski.
2) Centralize min/max MTU checking, thus removing tons of duplicated
code all of the the various drivers. From Jarod Wilson.
3) Support ingress actions in act_mirred, from Shmulik Ladkani.
4) Improve device adjacency tracking, from David Ahern.
5) Add support for LED triggers on PHY link state changes, from Zach
Brown.
6) Improve UDP socket memory accounting, from Paolo Abeni.
7) Set SK_MEM_QUANTUM to a fixed size of 4096, instead of PAGE_SIZE.
From Eric Dumazet.
8) Collapse TCP SKBs at retransmit time even if the right side SKB has
frags. Also from Eric Dumazet.
9) Add IP_RECVFRAGSIZE and IPV6_RECVFRAGSIZE cmsgs, from Willem de
Bruijn.
10) Support routing by UID, from Lorenzo Colitti.
11) Handle L3 domain binding (ie. VRF) for RAW sockets, from David
Ahern.
12) tcp_get_info() can run lockless, from Eric Dumazet.
13) 4-tuple UDP hashing in SFC driver, from Edward Cree.
14) Avoid reorders in GRO code, from Eric Dumazet.
15) IPV6 Segment Routing support, from David Lebrun.
16) Support MPLS push and pop for L3 packets in openvswitch, from Jiri
Benc.
17) Add LRU datastructure support for BPF, Martin KaFai Lau.
18) VF support in liquidio driver, from Raghu Vatsavayi.
19) Multiqueue support in alx driver, from Tobias Regnery.
20) Networking cgroup BPF support, from Daniel Mack.
21) TCP chronograph measurements, from Francis Yan.
22) XDP support for qed driver, from Yuval Mintz.
23) BPF based lwtunnels, from Thomas Graf.
24) Consistent FIB dumping to offloading drivers, from Ido Schimmel.
25) Many optimizations for UDP under high load, from Eric Dumazet.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1522 commits)
netfilter: nft_counter: rework atomic dump and reset
e1000: use disable_hardirq() for e1000_netpoll()
i40e: don't truncate match_method assignment
net: ethernet: ti: netcp: add support of cpts
net: phy: phy drivers should not set SUPPORTED_[Asym_]Pause
net: l2tp: ppp: change PPPOL2TP_MSG_* => L2TP_MSG_*
net: l2tp: deprecate PPPOL2TP_MSG_* in favour of L2TP_MSG_*
net: l2tp: export debug flags to UAPI
net: ethernet: stmmac: remove private tx queue lock
net: ethernet: sxgbe: remove private tx queue lock
net: bridge: shorten ageing time on topology change
net: bridge: add helper to set topology change
net: bridge: add helper to offload ageing time
net: nicvf: use new api ethtool_{get|set}_link_ksettings
net: ethernet: ti: cpsw: sync rates for channels in dual emac mode
net: ethernet: ti: cpsw: re-split res only when speed is changed
net: ethernet: ti: cpsw: combine budget and weight split and check
net: ethernet: ti: cpsw: don't start queue twice
net: ethernet: ti: cpsw: use same macros to get active slave
net: mvneta: select GENERIC_ALLOCATOR
...
Diffstat (limited to 'drivers/net/ethernet/sfc/tx_tso.c')
-rw-r--r-- | drivers/net/ethernet/sfc/tx_tso.c | 451 |
1 files changed, 451 insertions, 0 deletions
diff --git a/drivers/net/ethernet/sfc/tx_tso.c b/drivers/net/ethernet/sfc/tx_tso.c new file mode 100644 index 000000000000..e0cbda9ae859 --- /dev/null +++ b/drivers/net/ethernet/sfc/tx_tso.c @@ -0,0 +1,451 @@ +/**************************************************************************** + * Driver for Solarflare network controllers and boards + * Copyright 2005-2006 Fen Systems Ltd. + * Copyright 2005-2015 Solarflare Communications Inc. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published + * by the Free Software Foundation, incorporated herein by reference. + */ + +#include <linux/pci.h> +#include <linux/tcp.h> +#include <linux/ip.h> +#include <linux/in.h> +#include <linux/ipv6.h> +#include <linux/slab.h> +#include <net/ipv6.h> +#include <linux/if_ether.h> +#include <linux/highmem.h> +#include <linux/moduleparam.h> +#include <linux/cache.h> +#include "net_driver.h" +#include "efx.h" +#include "io.h" +#include "nic.h" +#include "tx.h" +#include "workarounds.h" +#include "ef10_regs.h" + +/* Efx legacy TCP segmentation acceleration. + * + * Utilises firmware support to go faster than GSO (but not as fast as TSOv2). + * + * Requires TX checksum offload support. + */ + +#define PTR_DIFF(p1, p2) ((u8 *)(p1) - (u8 *)(p2)) + +/** + * struct tso_state - TSO state for an SKB + * @out_len: Remaining length in current segment + * @seqnum: Current sequence number + * @ipv4_id: Current IPv4 ID, host endian + * @packet_space: Remaining space in current packet + * @dma_addr: DMA address of current position + * @in_len: Remaining length in current SKB fragment + * @unmap_len: Length of SKB fragment + * @unmap_addr: DMA address of SKB fragment + * @protocol: Network protocol (after any VLAN header) + * @ip_off: Offset of IP header + * @tcp_off: Offset of TCP header + * @header_len: Number of bytes of header + * @ip_base_len: IPv4 tot_len or IPv6 payload_len, before TCP payload + * @header_dma_addr: Header DMA address + * @header_unmap_len: Header DMA mapped length + * + * The state used during segmentation. It is put into this data structure + * just to make it easy to pass into inline functions. + */ +struct tso_state { + /* Output position */ + unsigned int out_len; + unsigned int seqnum; + u16 ipv4_id; + unsigned int packet_space; + + /* Input position */ + dma_addr_t dma_addr; + unsigned int in_len; + unsigned int unmap_len; + dma_addr_t unmap_addr; + + __be16 protocol; + unsigned int ip_off; + unsigned int tcp_off; + unsigned int header_len; + unsigned int ip_base_len; + dma_addr_t header_dma_addr; + unsigned int header_unmap_len; +}; + +static inline void prefetch_ptr(struct efx_tx_queue *tx_queue) +{ + unsigned int insert_ptr = efx_tx_queue_get_insert_index(tx_queue); + char *ptr; + + ptr = (char *) (tx_queue->buffer + insert_ptr); + prefetch(ptr); + prefetch(ptr + 0x80); + + ptr = (char *) (((efx_qword_t *)tx_queue->txd.buf.addr) + insert_ptr); + prefetch(ptr); + prefetch(ptr + 0x80); +} + +/** + * efx_tx_queue_insert - push descriptors onto the TX queue + * @tx_queue: Efx TX queue + * @dma_addr: DMA address of fragment + * @len: Length of fragment + * @final_buffer: The final buffer inserted into the queue + * + * Push descriptors onto the TX queue. + */ +static void efx_tx_queue_insert(struct efx_tx_queue *tx_queue, + dma_addr_t dma_addr, unsigned int len, + struct efx_tx_buffer **final_buffer) +{ + struct efx_tx_buffer *buffer; + unsigned int dma_len; + + EFX_WARN_ON_ONCE_PARANOID(len <= 0); + + while (1) { + buffer = efx_tx_queue_get_insert_buffer(tx_queue); + ++tx_queue->insert_count; + + EFX_WARN_ON_ONCE_PARANOID(tx_queue->insert_count - + tx_queue->read_count >= + tx_queue->efx->txq_entries); + + buffer->dma_addr = dma_addr; + + dma_len = tx_queue->efx->type->tx_limit_len(tx_queue, + dma_addr, len); + + /* If there's space for everything this is our last buffer. */ + if (dma_len >= len) + break; + + buffer->len = dma_len; + buffer->flags = EFX_TX_BUF_CONT; + dma_addr += dma_len; + len -= dma_len; + } + + EFX_WARN_ON_ONCE_PARANOID(!len); + buffer->len = len; + *final_buffer = buffer; +} + +/* + * Verify that our various assumptions about sk_buffs and the conditions + * under which TSO will be attempted hold true. Return the protocol number. + */ +static __be16 efx_tso_check_protocol(struct sk_buff *skb) +{ + __be16 protocol = skb->protocol; + + EFX_WARN_ON_ONCE_PARANOID(((struct ethhdr *)skb->data)->h_proto != + protocol); + if (protocol == htons(ETH_P_8021Q)) { + struct vlan_ethhdr *veh = (struct vlan_ethhdr *)skb->data; + + protocol = veh->h_vlan_encapsulated_proto; + } + + if (protocol == htons(ETH_P_IP)) { + EFX_WARN_ON_ONCE_PARANOID(ip_hdr(skb)->protocol != IPPROTO_TCP); + } else { + EFX_WARN_ON_ONCE_PARANOID(protocol != htons(ETH_P_IPV6)); + EFX_WARN_ON_ONCE_PARANOID(ipv6_hdr(skb)->nexthdr != NEXTHDR_TCP); + } + EFX_WARN_ON_ONCE_PARANOID((PTR_DIFF(tcp_hdr(skb), skb->data) + + (tcp_hdr(skb)->doff << 2u)) > + skb_headlen(skb)); + + return protocol; +} + +/* Parse the SKB header and initialise state. */ +static int tso_start(struct tso_state *st, struct efx_nic *efx, + struct efx_tx_queue *tx_queue, + const struct sk_buff *skb) +{ + struct device *dma_dev = &efx->pci_dev->dev; + unsigned int header_len, in_len; + dma_addr_t dma_addr; + + st->ip_off = skb_network_header(skb) - skb->data; + st->tcp_off = skb_transport_header(skb) - skb->data; + header_len = st->tcp_off + (tcp_hdr(skb)->doff << 2u); + in_len = skb_headlen(skb) - header_len; + st->header_len = header_len; + st->in_len = in_len; + if (st->protocol == htons(ETH_P_IP)) { + st->ip_base_len = st->header_len - st->ip_off; + st->ipv4_id = ntohs(ip_hdr(skb)->id); + } else { + st->ip_base_len = st->header_len - st->tcp_off; + st->ipv4_id = 0; + } + st->seqnum = ntohl(tcp_hdr(skb)->seq); + + EFX_WARN_ON_ONCE_PARANOID(tcp_hdr(skb)->urg); + EFX_WARN_ON_ONCE_PARANOID(tcp_hdr(skb)->syn); + EFX_WARN_ON_ONCE_PARANOID(tcp_hdr(skb)->rst); + + st->out_len = skb->len - header_len; + + dma_addr = dma_map_single(dma_dev, skb->data, + skb_headlen(skb), DMA_TO_DEVICE); + st->header_dma_addr = dma_addr; + st->header_unmap_len = skb_headlen(skb); + st->dma_addr = dma_addr + header_len; + st->unmap_len = 0; + + return unlikely(dma_mapping_error(dma_dev, dma_addr)) ? -ENOMEM : 0; +} + +static int tso_get_fragment(struct tso_state *st, struct efx_nic *efx, + skb_frag_t *frag) +{ + st->unmap_addr = skb_frag_dma_map(&efx->pci_dev->dev, frag, 0, + skb_frag_size(frag), DMA_TO_DEVICE); + if (likely(!dma_mapping_error(&efx->pci_dev->dev, st->unmap_addr))) { + st->unmap_len = skb_frag_size(frag); + st->in_len = skb_frag_size(frag); + st->dma_addr = st->unmap_addr; + return 0; + } + return -ENOMEM; +} + + +/** + * tso_fill_packet_with_fragment - form descriptors for the current fragment + * @tx_queue: Efx TX queue + * @skb: Socket buffer + * @st: TSO state + * + * Form descriptors for the current fragment, until we reach the end + * of fragment or end-of-packet. + */ +static void tso_fill_packet_with_fragment(struct efx_tx_queue *tx_queue, + const struct sk_buff *skb, + struct tso_state *st) +{ + struct efx_tx_buffer *buffer; + int n; + + if (st->in_len == 0) + return; + if (st->packet_space == 0) + return; + + EFX_WARN_ON_ONCE_PARANOID(st->in_len <= 0); + EFX_WARN_ON_ONCE_PARANOID(st->packet_space <= 0); + + n = min(st->in_len, st->packet_space); + + st->packet_space -= n; + st->out_len -= n; + st->in_len -= n; + + efx_tx_queue_insert(tx_queue, st->dma_addr, n, &buffer); + + if (st->out_len == 0) { + /* Transfer ownership of the skb */ + buffer->skb = skb; + buffer->flags = EFX_TX_BUF_SKB; + } else if (st->packet_space != 0) { + buffer->flags = EFX_TX_BUF_CONT; + } + + if (st->in_len == 0) { + /* Transfer ownership of the DMA mapping */ + buffer->unmap_len = st->unmap_len; + buffer->dma_offset = buffer->unmap_len - buffer->len; + st->unmap_len = 0; + } + + st->dma_addr += n; +} + + +#define TCP_FLAGS_OFFSET 13 + +/** + * tso_start_new_packet - generate a new header and prepare for the new packet + * @tx_queue: Efx TX queue + * @skb: Socket buffer + * @st: TSO state + * + * Generate a new header and prepare for the new packet. Return 0 on + * success, or -%ENOMEM if failed to alloc header, or other negative error. + */ +static int tso_start_new_packet(struct efx_tx_queue *tx_queue, + const struct sk_buff *skb, + struct tso_state *st) +{ + struct efx_tx_buffer *buffer = + efx_tx_queue_get_insert_buffer(tx_queue); + bool is_last = st->out_len <= skb_shinfo(skb)->gso_size; + u8 tcp_flags_mask, tcp_flags; + + if (!is_last) { + st->packet_space = skb_shinfo(skb)->gso_size; + tcp_flags_mask = 0x09; /* mask out FIN and PSH */ + } else { + st->packet_space = st->out_len; + tcp_flags_mask = 0x00; + } + + if (WARN_ON(!st->header_unmap_len)) + return -EINVAL; + /* Send the original headers with a TSO option descriptor + * in front + */ + tcp_flags = ((u8 *)tcp_hdr(skb))[TCP_FLAGS_OFFSET] & ~tcp_flags_mask; + + buffer->flags = EFX_TX_BUF_OPTION; + buffer->len = 0; + buffer->unmap_len = 0; + EFX_POPULATE_QWORD_5(buffer->option, + ESF_DZ_TX_DESC_IS_OPT, 1, + ESF_DZ_TX_OPTION_TYPE, + ESE_DZ_TX_OPTION_DESC_TSO, + ESF_DZ_TX_TSO_TCP_FLAGS, tcp_flags, + ESF_DZ_TX_TSO_IP_ID, st->ipv4_id, + ESF_DZ_TX_TSO_TCP_SEQNO, st->seqnum); + ++tx_queue->insert_count; + + /* We mapped the headers in tso_start(). Unmap them + * when the last segment is completed. + */ + buffer = efx_tx_queue_get_insert_buffer(tx_queue); + buffer->dma_addr = st->header_dma_addr; + buffer->len = st->header_len; + if (is_last) { + buffer->flags = EFX_TX_BUF_CONT | EFX_TX_BUF_MAP_SINGLE; + buffer->unmap_len = st->header_unmap_len; + buffer->dma_offset = 0; + /* Ensure we only unmap them once in case of a + * later DMA mapping error and rollback + */ + st->header_unmap_len = 0; + } else { + buffer->flags = EFX_TX_BUF_CONT; + buffer->unmap_len = 0; + } + ++tx_queue->insert_count; + + st->seqnum += skb_shinfo(skb)->gso_size; + + /* Linux leaves suitable gaps in the IP ID space for us to fill. */ + ++st->ipv4_id; + + return 0; +} + +/** + * efx_enqueue_skb_tso - segment and transmit a TSO socket buffer + * @tx_queue: Efx TX queue + * @skb: Socket buffer + * @data_mapped: Did we map the data? Always set to true + * by this on success. + * + * Context: You must hold netif_tx_lock() to call this function. + * + * Add socket buffer @skb to @tx_queue, doing TSO or return != 0 if + * @skb was not enqueued. @skb is consumed unless return value is + * %EINVAL. + */ +int efx_enqueue_skb_tso(struct efx_tx_queue *tx_queue, + struct sk_buff *skb, + bool *data_mapped) +{ + struct efx_nic *efx = tx_queue->efx; + int frag_i, rc; + struct tso_state state; + + if (tx_queue->tso_version != 1) + return -EINVAL; + + prefetch(skb->data); + + /* Find the packet protocol and sanity-check it */ + state.protocol = efx_tso_check_protocol(skb); + + EFX_WARN_ON_ONCE_PARANOID(tx_queue->write_count != tx_queue->insert_count); + + rc = tso_start(&state, efx, tx_queue, skb); + if (rc) + goto fail; + + if (likely(state.in_len == 0)) { + /* Grab the first payload fragment. */ + EFX_WARN_ON_ONCE_PARANOID(skb_shinfo(skb)->nr_frags < 1); + frag_i = 0; + rc = tso_get_fragment(&state, efx, + skb_shinfo(skb)->frags + frag_i); + if (rc) + goto fail; + } else { + /* Payload starts in the header area. */ + frag_i = -1; + } + + rc = tso_start_new_packet(tx_queue, skb, &state); + if (rc) + goto fail; + + prefetch_ptr(tx_queue); + + while (1) { + tso_fill_packet_with_fragment(tx_queue, skb, &state); + + /* Move onto the next fragment? */ + if (state.in_len == 0) { + if (++frag_i >= skb_shinfo(skb)->nr_frags) + /* End of payload reached. */ + break; + rc = tso_get_fragment(&state, efx, + skb_shinfo(skb)->frags + frag_i); + if (rc) + goto fail; + } + + /* Start at new packet? */ + if (state.packet_space == 0) { + rc = tso_start_new_packet(tx_queue, skb, &state); + if (rc) + goto fail; + } + } + + *data_mapped = true; + + return 0; + +fail: + if (rc == -ENOMEM) + netif_err(efx, tx_err, efx->net_dev, + "Out of memory for TSO headers, or DMA mapping error\n"); + else + netif_err(efx, tx_err, efx->net_dev, "TSO failed, rc = %d\n", rc); + + /* Free the DMA mapping we were in the process of writing out */ + if (state.unmap_len) { + dma_unmap_page(&efx->pci_dev->dev, state.unmap_addr, + state.unmap_len, DMA_TO_DEVICE); + } + + /* Free the header DMA mapping */ + if (state.header_unmap_len) + dma_unmap_single(&efx->pci_dev->dev, state.header_dma_addr, + state.header_unmap_len, DMA_TO_DEVICE); + + return rc; +} |