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Diffstat (limited to 'drivers/net/ethernet/intel/fm10k/fm10k_main.c')
-rw-r--r--drivers/net/ethernet/intel/fm10k/fm10k_main.c1981
1 files changed, 1981 insertions, 0 deletions
diff --git a/drivers/net/ethernet/intel/fm10k/fm10k_main.c b/drivers/net/ethernet/intel/fm10k/fm10k_main.c
new file mode 100644
index 000000000000..e645af412e76
--- /dev/null
+++ b/drivers/net/ethernet/intel/fm10k/fm10k_main.c
@@ -0,0 +1,1981 @@
+/* Intel Ethernet Switch Host Interface Driver
+ * Copyright(c) 2013 - 2014 Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * The full GNU General Public License is included in this distribution in
+ * the file called "COPYING".
+ *
+ * Contact Information:
+ * e1000-devel Mailing List <e1000-devel@lists.sourceforge.net>
+ * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
+ */
+
+#include <linux/types.h>
+#include <linux/module.h>
+#include <net/ipv6.h>
+#include <net/ip.h>
+#include <net/tcp.h>
+#include <linux/if_macvlan.h>
+#include <linux/prefetch.h>
+
+#include "fm10k.h"
+
+#define DRV_VERSION "0.12.2-k"
+const char fm10k_driver_version[] = DRV_VERSION;
+char fm10k_driver_name[] = "fm10k";
+static const char fm10k_driver_string[] =
+ "Intel(R) Ethernet Switch Host Interface Driver";
+static const char fm10k_copyright[] =
+ "Copyright (c) 2013 Intel Corporation.";
+
+MODULE_AUTHOR("Intel Corporation, <linux.nics@intel.com>");
+MODULE_DESCRIPTION("Intel(R) Ethernet Switch Host Interface Driver");
+MODULE_LICENSE("GPL");
+MODULE_VERSION(DRV_VERSION);
+
+/**
+ * fm10k_init_module - Driver Registration Routine
+ *
+ * fm10k_init_module is the first routine called when the driver is
+ * loaded. All it does is register with the PCI subsystem.
+ **/
+static int __init fm10k_init_module(void)
+{
+ pr_info("%s - version %s\n", fm10k_driver_string, fm10k_driver_version);
+ pr_info("%s\n", fm10k_copyright);
+
+ fm10k_dbg_init();
+
+ return fm10k_register_pci_driver();
+}
+module_init(fm10k_init_module);
+
+/**
+ * fm10k_exit_module - Driver Exit Cleanup Routine
+ *
+ * fm10k_exit_module is called just before the driver is removed
+ * from memory.
+ **/
+static void __exit fm10k_exit_module(void)
+{
+ fm10k_unregister_pci_driver();
+
+ fm10k_dbg_exit();
+}
+module_exit(fm10k_exit_module);
+
+static bool fm10k_alloc_mapped_page(struct fm10k_ring *rx_ring,
+ struct fm10k_rx_buffer *bi)
+{
+ struct page *page = bi->page;
+ dma_addr_t dma;
+
+ /* Only page will be NULL if buffer was consumed */
+ if (likely(page))
+ return true;
+
+ /* alloc new page for storage */
+ page = alloc_page(GFP_ATOMIC | __GFP_COLD);
+ if (unlikely(!page)) {
+ rx_ring->rx_stats.alloc_failed++;
+ return false;
+ }
+
+ /* map page for use */
+ dma = dma_map_page(rx_ring->dev, page, 0, PAGE_SIZE, DMA_FROM_DEVICE);
+
+ /* if mapping failed free memory back to system since
+ * there isn't much point in holding memory we can't use
+ */
+ if (dma_mapping_error(rx_ring->dev, dma)) {
+ __free_page(page);
+ bi->page = NULL;
+
+ rx_ring->rx_stats.alloc_failed++;
+ return false;
+ }
+
+ bi->dma = dma;
+ bi->page = page;
+ bi->page_offset = 0;
+
+ return true;
+}
+
+/**
+ * fm10k_alloc_rx_buffers - Replace used receive buffers
+ * @rx_ring: ring to place buffers on
+ * @cleaned_count: number of buffers to replace
+ **/
+void fm10k_alloc_rx_buffers(struct fm10k_ring *rx_ring, u16 cleaned_count)
+{
+ union fm10k_rx_desc *rx_desc;
+ struct fm10k_rx_buffer *bi;
+ u16 i = rx_ring->next_to_use;
+
+ /* nothing to do */
+ if (!cleaned_count)
+ return;
+
+ rx_desc = FM10K_RX_DESC(rx_ring, i);
+ bi = &rx_ring->rx_buffer[i];
+ i -= rx_ring->count;
+
+ do {
+ if (!fm10k_alloc_mapped_page(rx_ring, bi))
+ break;
+
+ /* Refresh the desc even if buffer_addrs didn't change
+ * because each write-back erases this info.
+ */
+ rx_desc->q.pkt_addr = cpu_to_le64(bi->dma + bi->page_offset);
+
+ rx_desc++;
+ bi++;
+ i++;
+ if (unlikely(!i)) {
+ rx_desc = FM10K_RX_DESC(rx_ring, 0);
+ bi = rx_ring->rx_buffer;
+ i -= rx_ring->count;
+ }
+
+ /* clear the hdr_addr for the next_to_use descriptor */
+ rx_desc->q.hdr_addr = 0;
+
+ cleaned_count--;
+ } while (cleaned_count);
+
+ i += rx_ring->count;
+
+ if (rx_ring->next_to_use != i) {
+ /* record the next descriptor to use */
+ rx_ring->next_to_use = i;
+
+ /* update next to alloc since we have filled the ring */
+ rx_ring->next_to_alloc = i;
+
+ /* Force memory writes to complete before letting h/w
+ * know there are new descriptors to fetch. (Only
+ * applicable for weak-ordered memory model archs,
+ * such as IA-64).
+ */
+ wmb();
+
+ /* notify hardware of new descriptors */
+ writel(i, rx_ring->tail);
+ }
+}
+
+/**
+ * fm10k_reuse_rx_page - page flip buffer and store it back on the ring
+ * @rx_ring: rx descriptor ring to store buffers on
+ * @old_buff: donor buffer to have page reused
+ *
+ * Synchronizes page for reuse by the interface
+ **/
+static void fm10k_reuse_rx_page(struct fm10k_ring *rx_ring,
+ struct fm10k_rx_buffer *old_buff)
+{
+ struct fm10k_rx_buffer *new_buff;
+ u16 nta = rx_ring->next_to_alloc;
+
+ new_buff = &rx_ring->rx_buffer[nta];
+
+ /* update, and store next to alloc */
+ nta++;
+ rx_ring->next_to_alloc = (nta < rx_ring->count) ? nta : 0;
+
+ /* transfer page from old buffer to new buffer */
+ memcpy(new_buff, old_buff, sizeof(struct fm10k_rx_buffer));
+
+ /* sync the buffer for use by the device */
+ dma_sync_single_range_for_device(rx_ring->dev, old_buff->dma,
+ old_buff->page_offset,
+ FM10K_RX_BUFSZ,
+ DMA_FROM_DEVICE);
+}
+
+static bool fm10k_can_reuse_rx_page(struct fm10k_rx_buffer *rx_buffer,
+ struct page *page,
+ unsigned int truesize)
+{
+ /* avoid re-using remote pages */
+ if (unlikely(page_to_nid(page) != numa_mem_id()))
+ return false;
+
+#if (PAGE_SIZE < 8192)
+ /* if we are only owner of page we can reuse it */
+ if (unlikely(page_count(page) != 1))
+ return false;
+
+ /* flip page offset to other buffer */
+ rx_buffer->page_offset ^= FM10K_RX_BUFSZ;
+
+ /* Even if we own the page, we are not allowed to use atomic_set()
+ * This would break get_page_unless_zero() users.
+ */
+ atomic_inc(&page->_count);
+#else
+ /* move offset up to the next cache line */
+ rx_buffer->page_offset += truesize;
+
+ if (rx_buffer->page_offset > (PAGE_SIZE - FM10K_RX_BUFSZ))
+ return false;
+
+ /* bump ref count on page before it is given to the stack */
+ get_page(page);
+#endif
+
+ return true;
+}
+
+/**
+ * fm10k_add_rx_frag - Add contents of Rx buffer to sk_buff
+ * @rx_ring: rx descriptor ring to transact packets on
+ * @rx_buffer: buffer containing page to add
+ * @rx_desc: descriptor containing length of buffer written by hardware
+ * @skb: sk_buff to place the data into
+ *
+ * This function will add the data contained in rx_buffer->page to the skb.
+ * This is done either through a direct copy if the data in the buffer is
+ * less than the skb header size, otherwise it will just attach the page as
+ * a frag to the skb.
+ *
+ * The function will then update the page offset if necessary and return
+ * true if the buffer can be reused by the interface.
+ **/
+static bool fm10k_add_rx_frag(struct fm10k_ring *rx_ring,
+ struct fm10k_rx_buffer *rx_buffer,
+ union fm10k_rx_desc *rx_desc,
+ struct sk_buff *skb)
+{
+ struct page *page = rx_buffer->page;
+ unsigned int size = le16_to_cpu(rx_desc->w.length);
+#if (PAGE_SIZE < 8192)
+ unsigned int truesize = FM10K_RX_BUFSZ;
+#else
+ unsigned int truesize = ALIGN(size, L1_CACHE_BYTES);
+#endif
+
+ if ((size <= FM10K_RX_HDR_LEN) && !skb_is_nonlinear(skb)) {
+ unsigned char *va = page_address(page) + rx_buffer->page_offset;
+
+ memcpy(__skb_put(skb, size), va, ALIGN(size, sizeof(long)));
+
+ /* we can reuse buffer as-is, just make sure it is local */
+ if (likely(page_to_nid(page) == numa_mem_id()))
+ return true;
+
+ /* this page cannot be reused so discard it */
+ put_page(page);
+ return false;
+ }
+
+ skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags, page,
+ rx_buffer->page_offset, size, truesize);
+
+ return fm10k_can_reuse_rx_page(rx_buffer, page, truesize);
+}
+
+static struct sk_buff *fm10k_fetch_rx_buffer(struct fm10k_ring *rx_ring,
+ union fm10k_rx_desc *rx_desc,
+ struct sk_buff *skb)
+{
+ struct fm10k_rx_buffer *rx_buffer;
+ struct page *page;
+
+ rx_buffer = &rx_ring->rx_buffer[rx_ring->next_to_clean];
+
+ page = rx_buffer->page;
+ prefetchw(page);
+
+ if (likely(!skb)) {
+ void *page_addr = page_address(page) +
+ rx_buffer->page_offset;
+
+ /* prefetch first cache line of first page */
+ prefetch(page_addr);
+#if L1_CACHE_BYTES < 128
+ prefetch(page_addr + L1_CACHE_BYTES);
+#endif
+
+ /* allocate a skb to store the frags */
+ skb = netdev_alloc_skb_ip_align(rx_ring->netdev,
+ FM10K_RX_HDR_LEN);
+ if (unlikely(!skb)) {
+ rx_ring->rx_stats.alloc_failed++;
+ return NULL;
+ }
+
+ /* we will be copying header into skb->data in
+ * pskb_may_pull so it is in our interest to prefetch
+ * it now to avoid a possible cache miss
+ */
+ prefetchw(skb->data);
+ }
+
+ /* we are reusing so sync this buffer for CPU use */
+ dma_sync_single_range_for_cpu(rx_ring->dev,
+ rx_buffer->dma,
+ rx_buffer->page_offset,
+ FM10K_RX_BUFSZ,
+ DMA_FROM_DEVICE);
+
+ /* pull page into skb */
+ if (fm10k_add_rx_frag(rx_ring, rx_buffer, rx_desc, skb)) {
+ /* hand second half of page back to the ring */
+ fm10k_reuse_rx_page(rx_ring, rx_buffer);
+ } else {
+ /* we are not reusing the buffer so unmap it */
+ dma_unmap_page(rx_ring->dev, rx_buffer->dma,
+ PAGE_SIZE, DMA_FROM_DEVICE);
+ }
+
+ /* clear contents of rx_buffer */
+ rx_buffer->page = NULL;
+
+ return skb;
+}
+
+static inline void fm10k_rx_checksum(struct fm10k_ring *ring,
+ union fm10k_rx_desc *rx_desc,
+ struct sk_buff *skb)
+{
+ skb_checksum_none_assert(skb);
+
+ /* Rx checksum disabled via ethtool */
+ if (!(ring->netdev->features & NETIF_F_RXCSUM))
+ return;
+
+ /* TCP/UDP checksum error bit is set */
+ if (fm10k_test_staterr(rx_desc,
+ FM10K_RXD_STATUS_L4E |
+ FM10K_RXD_STATUS_L4E2 |
+ FM10K_RXD_STATUS_IPE |
+ FM10K_RXD_STATUS_IPE2)) {
+ ring->rx_stats.csum_err++;
+ return;
+ }
+
+ /* It must be a TCP or UDP packet with a valid checksum */
+ if (fm10k_test_staterr(rx_desc, FM10K_RXD_STATUS_L4CS2))
+ skb->encapsulation = true;
+ else if (!fm10k_test_staterr(rx_desc, FM10K_RXD_STATUS_L4CS))
+ return;
+
+ skb->ip_summed = CHECKSUM_UNNECESSARY;
+}
+
+#define FM10K_RSS_L4_TYPES_MASK \
+ ((1ul << FM10K_RSSTYPE_IPV4_TCP) | \
+ (1ul << FM10K_RSSTYPE_IPV4_UDP) | \
+ (1ul << FM10K_RSSTYPE_IPV6_TCP) | \
+ (1ul << FM10K_RSSTYPE_IPV6_UDP))
+
+static inline void fm10k_rx_hash(struct fm10k_ring *ring,
+ union fm10k_rx_desc *rx_desc,
+ struct sk_buff *skb)
+{
+ u16 rss_type;
+
+ if (!(ring->netdev->features & NETIF_F_RXHASH))
+ return;
+
+ rss_type = le16_to_cpu(rx_desc->w.pkt_info) & FM10K_RXD_RSSTYPE_MASK;
+ if (!rss_type)
+ return;
+
+ skb_set_hash(skb, le32_to_cpu(rx_desc->d.rss),
+ (FM10K_RSS_L4_TYPES_MASK & (1ul << rss_type)) ?
+ PKT_HASH_TYPE_L4 : PKT_HASH_TYPE_L3);
+}
+
+static void fm10k_rx_hwtstamp(struct fm10k_ring *rx_ring,
+ union fm10k_rx_desc *rx_desc,
+ struct sk_buff *skb)
+{
+ struct fm10k_intfc *interface = rx_ring->q_vector->interface;
+
+ FM10K_CB(skb)->tstamp = rx_desc->q.timestamp;
+
+ if (unlikely(interface->flags & FM10K_FLAG_RX_TS_ENABLED))
+ fm10k_systime_to_hwtstamp(interface, skb_hwtstamps(skb),
+ le64_to_cpu(rx_desc->q.timestamp));
+}
+
+static void fm10k_type_trans(struct fm10k_ring *rx_ring,
+ union fm10k_rx_desc *rx_desc,
+ struct sk_buff *skb)
+{
+ struct net_device *dev = rx_ring->netdev;
+ struct fm10k_l2_accel *l2_accel = rcu_dereference_bh(rx_ring->l2_accel);
+
+ /* check to see if DGLORT belongs to a MACVLAN */
+ if (l2_accel) {
+ u16 idx = le16_to_cpu(FM10K_CB(skb)->fi.w.dglort) - 1;
+
+ idx -= l2_accel->dglort;
+ if (idx < l2_accel->size && l2_accel->macvlan[idx])
+ dev = l2_accel->macvlan[idx];
+ else
+ l2_accel = NULL;
+ }
+
+ skb->protocol = eth_type_trans(skb, dev);
+
+ if (!l2_accel)
+ return;
+
+ /* update MACVLAN statistics */
+ macvlan_count_rx(netdev_priv(dev), skb->len + ETH_HLEN, 1,
+ !!(rx_desc->w.hdr_info &
+ cpu_to_le16(FM10K_RXD_HDR_INFO_XC_MASK)));
+}
+
+/**
+ * fm10k_process_skb_fields - Populate skb header fields from Rx descriptor
+ * @rx_ring: rx descriptor ring packet is being transacted on
+ * @rx_desc: pointer to the EOP Rx descriptor
+ * @skb: pointer to current skb being populated
+ *
+ * This function checks the ring, descriptor, and packet information in
+ * order to populate the hash, checksum, VLAN, timestamp, protocol, and
+ * other fields within the skb.
+ **/
+static unsigned int fm10k_process_skb_fields(struct fm10k_ring *rx_ring,
+ union fm10k_rx_desc *rx_desc,
+ struct sk_buff *skb)
+{
+ unsigned int len = skb->len;
+
+ fm10k_rx_hash(rx_ring, rx_desc, skb);
+
+ fm10k_rx_checksum(rx_ring, rx_desc, skb);
+
+ fm10k_rx_hwtstamp(rx_ring, rx_desc, skb);
+
+ FM10K_CB(skb)->fi.w.vlan = rx_desc->w.vlan;
+
+ skb_record_rx_queue(skb, rx_ring->queue_index);
+
+ FM10K_CB(skb)->fi.d.glort = rx_desc->d.glort;
+
+ if (rx_desc->w.vlan) {
+ u16 vid = le16_to_cpu(rx_desc->w.vlan);
+
+ if (vid != rx_ring->vid)
+ __vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q), vid);
+ }
+
+ fm10k_type_trans(rx_ring, rx_desc, skb);
+
+ return len;
+}
+
+/**
+ * fm10k_is_non_eop - process handling of non-EOP buffers
+ * @rx_ring: Rx ring being processed
+ * @rx_desc: Rx descriptor for current buffer
+ *
+ * This function updates next to clean. If the buffer is an EOP buffer
+ * this function exits returning false, otherwise it will place the
+ * sk_buff in the next buffer to be chained and return true indicating
+ * that this is in fact a non-EOP buffer.
+ **/
+static bool fm10k_is_non_eop(struct fm10k_ring *rx_ring,
+ union fm10k_rx_desc *rx_desc)
+{
+ u32 ntc = rx_ring->next_to_clean + 1;
+
+ /* fetch, update, and store next to clean */
+ ntc = (ntc < rx_ring->count) ? ntc : 0;
+ rx_ring->next_to_clean = ntc;
+
+ prefetch(FM10K_RX_DESC(rx_ring, ntc));
+
+ if (likely(fm10k_test_staterr(rx_desc, FM10K_RXD_STATUS_EOP)))
+ return false;
+
+ return true;
+}
+
+/**
+ * fm10k_pull_tail - fm10k specific version of skb_pull_tail
+ * @rx_ring: rx descriptor ring packet is being transacted on
+ * @rx_desc: pointer to the EOP Rx descriptor
+ * @skb: pointer to current skb being adjusted
+ *
+ * This function is an fm10k specific version of __pskb_pull_tail. The
+ * main difference between this version and the original function is that
+ * this function can make several assumptions about the state of things
+ * that allow for significant optimizations versus the standard function.
+ * As a result we can do things like drop a frag and maintain an accurate
+ * truesize for the skb.
+ */
+static void fm10k_pull_tail(struct fm10k_ring *rx_ring,
+ union fm10k_rx_desc *rx_desc,
+ struct sk_buff *skb)
+{
+ struct skb_frag_struct *frag = &skb_shinfo(skb)->frags[0];
+ unsigned char *va;
+ unsigned int pull_len;
+
+ /* it is valid to use page_address instead of kmap since we are
+ * working with pages allocated out of the lomem pool per
+ * alloc_page(GFP_ATOMIC)
+ */
+ va = skb_frag_address(frag);
+
+ /* we need the header to contain the greater of either ETH_HLEN or
+ * 60 bytes if the skb->len is less than 60 for skb_pad.
+ */
+ pull_len = eth_get_headlen(va, FM10K_RX_HDR_LEN);
+
+ /* align pull length to size of long to optimize memcpy performance */
+ skb_copy_to_linear_data(skb, va, ALIGN(pull_len, sizeof(long)));
+
+ /* update all of the pointers */
+ skb_frag_size_sub(frag, pull_len);
+ frag->page_offset += pull_len;
+ skb->data_len -= pull_len;
+ skb->tail += pull_len;
+}
+
+/**
+ * fm10k_cleanup_headers - Correct corrupted or empty headers
+ * @rx_ring: rx descriptor ring packet is being transacted on
+ * @rx_desc: pointer to the EOP Rx descriptor
+ * @skb: pointer to current skb being fixed
+ *
+ * Address the case where we are pulling data in on pages only
+ * and as such no data is present in the skb header.
+ *
+ * In addition if skb is not at least 60 bytes we need to pad it so that
+ * it is large enough to qualify as a valid Ethernet frame.
+ *
+ * Returns true if an error was encountered and skb was freed.
+ **/
+static bool fm10k_cleanup_headers(struct fm10k_ring *rx_ring,
+ union fm10k_rx_desc *rx_desc,
+ struct sk_buff *skb)
+{
+ if (unlikely((fm10k_test_staterr(rx_desc,
+ FM10K_RXD_STATUS_RXE)))) {
+ dev_kfree_skb_any(skb);
+ rx_ring->rx_stats.errors++;
+ return true;
+ }
+
+ /* place header in linear portion of buffer */
+ if (skb_is_nonlinear(skb))
+ fm10k_pull_tail(rx_ring, rx_desc, skb);
+
+ /* if skb_pad returns an error the skb was freed */
+ if (unlikely(skb->len < 60)) {
+ int pad_len = 60 - skb->len;
+
+ if (skb_pad(skb, pad_len))
+ return true;
+ __skb_put(skb, pad_len);
+ }
+
+ return false;
+}
+
+/**
+ * fm10k_receive_skb - helper function to handle rx indications
+ * @q_vector: structure containing interrupt and ring information
+ * @skb: packet to send up
+ **/
+static void fm10k_receive_skb(struct fm10k_q_vector *q_vector,
+ struct sk_buff *skb)
+{
+ napi_gro_receive(&q_vector->napi, skb);
+}
+
+static bool fm10k_clean_rx_irq(struct fm10k_q_vector *q_vector,
+ struct fm10k_ring *rx_ring,
+ int budget)
+{
+ struct sk_buff *skb = rx_ring->skb;
+ unsigned int total_bytes = 0, total_packets = 0;
+ u16 cleaned_count = fm10k_desc_unused(rx_ring);
+
+ do {
+ union fm10k_rx_desc *rx_desc;
+
+ /* return some buffers to hardware, one at a time is too slow */
+ if (cleaned_count >= FM10K_RX_BUFFER_WRITE) {
+ fm10k_alloc_rx_buffers(rx_ring, cleaned_count);
+ cleaned_count = 0;
+ }
+
+ rx_desc = FM10K_RX_DESC(rx_ring, rx_ring->next_to_clean);
+
+ if (!fm10k_test_staterr(rx_desc, FM10K_RXD_STATUS_DD))
+ break;
+
+ /* This memory barrier is needed to keep us from reading
+ * any other fields out of the rx_desc until we know the
+ * RXD_STATUS_DD bit is set
+ */
+ rmb();
+
+ /* retrieve a buffer from the ring */
+ skb = fm10k_fetch_rx_buffer(rx_ring, rx_desc, skb);
+
+ /* exit if we failed to retrieve a buffer */
+ if (!skb)
+ break;
+
+ cleaned_count++;
+
+ /* fetch next buffer in frame if non-eop */
+ if (fm10k_is_non_eop(rx_ring, rx_desc))
+ continue;
+
+ /* verify the packet layout is correct */
+ if (fm10k_cleanup_headers(rx_ring, rx_desc, skb)) {
+ skb = NULL;
+ continue;
+ }
+
+ /* populate checksum, timestamp, VLAN, and protocol */
+ total_bytes += fm10k_process_skb_fields(rx_ring, rx_desc, skb);
+
+ fm10k_receive_skb(q_vector, skb);
+
+ /* reset skb pointer */
+ skb = NULL;
+
+ /* update budget accounting */
+ total_packets++;
+ } while (likely(total_packets < budget));
+
+ /* place incomplete frames back on ring for completion */
+ rx_ring->skb = skb;
+
+ u64_stats_update_begin(&rx_ring->syncp);
+ rx_ring->stats.packets += total_packets;
+ rx_ring->stats.bytes += total_bytes;
+ u64_stats_update_end(&rx_ring->syncp);
+ q_vector->rx.total_packets += total_packets;
+ q_vector->rx.total_bytes += total_bytes;
+
+ return total_packets < budget;
+}
+
+#define VXLAN_HLEN (sizeof(struct udphdr) + 8)
+static struct ethhdr *fm10k_port_is_vxlan(struct sk_buff *skb)
+{
+ struct fm10k_intfc *interface = netdev_priv(skb->dev);
+ struct fm10k_vxlan_port *vxlan_port;
+
+ /* we can only offload a vxlan if we recognize it as such */
+ vxlan_port = list_first_entry_or_null(&interface->vxlan_port,
+ struct fm10k_vxlan_port, list);
+
+ if (!vxlan_port)
+ return NULL;
+ if (vxlan_port->port != udp_hdr(skb)->dest)
+ return NULL;
+
+ /* return offset of udp_hdr plus 8 bytes for VXLAN header */
+ return (struct ethhdr *)(skb_transport_header(skb) + VXLAN_HLEN);
+}
+
+#define FM10K_NVGRE_RESERVED0_FLAGS htons(0x9FFF)
+#define NVGRE_TNI htons(0x2000)
+struct fm10k_nvgre_hdr {
+ __be16 flags;
+ __be16 proto;
+ __be32 tni;
+};
+
+static struct ethhdr *fm10k_gre_is_nvgre(struct sk_buff *skb)
+{
+ struct fm10k_nvgre_hdr *nvgre_hdr;
+ int hlen = ip_hdrlen(skb);
+
+ /* currently only IPv4 is supported due to hlen above */
+ if (vlan_get_protocol(skb) != htons(ETH_P_IP))
+ return NULL;
+
+ /* our transport header should be NVGRE */
+ nvgre_hdr = (struct fm10k_nvgre_hdr *)(skb_network_header(skb) + hlen);
+
+ /* verify all reserved flags are 0 */
+ if (nvgre_hdr->flags & FM10K_NVGRE_RESERVED0_FLAGS)
+ return NULL;
+
+ /* verify protocol is transparent Ethernet bridging */
+ if (nvgre_hdr->proto != htons(ETH_P_TEB))
+ return NULL;
+
+ /* report start of ethernet header */
+ if (nvgre_hdr->flags & NVGRE_TNI)
+ return (struct ethhdr *)(nvgre_hdr + 1);
+
+ return (struct ethhdr *)(&nvgre_hdr->tni);
+}
+
+static __be16 fm10k_tx_encap_offload(struct sk_buff *skb)
+{
+ struct ethhdr *eth_hdr;
+ u8 l4_hdr = 0;
+
+ switch (vlan_get_protocol(skb)) {
+ case htons(ETH_P_IP):
+ l4_hdr = ip_hdr(skb)->protocol;
+ break;
+ case htons(ETH_P_IPV6):
+ l4_hdr = ipv6_hdr(skb)->nexthdr;
+ break;
+ default:
+ return 0;
+ }
+
+ switch (l4_hdr) {
+ case IPPROTO_UDP:
+ eth_hdr = fm10k_port_is_vxlan(skb);
+ break;
+ case IPPROTO_GRE:
+ eth_hdr = fm10k_gre_is_nvgre(skb);
+ break;
+ default:
+ return 0;
+ }
+
+ if (!eth_hdr)
+ return 0;
+
+ switch (eth_hdr->h_proto) {
+ case htons(ETH_P_IP):
+ case htons(ETH_P_IPV6):
+ break;
+ default:
+ return 0;
+ }
+
+ return eth_hdr->h_proto;
+}
+
+static int fm10k_tso(struct fm10k_ring *tx_ring,
+ struct fm10k_tx_buffer *first)
+{
+ struct sk_buff *skb = first->skb;
+ struct fm10k_tx_desc *tx_desc;
+ unsigned char *th;
+ u8 hdrlen;
+
+ if (skb->ip_summed != CHECKSUM_PARTIAL)
+ return 0;
+
+ if (!skb_is_gso(skb))
+ return 0;
+
+ /* compute header lengths */
+ if (skb->encapsulation) {
+ if (!fm10k_tx_encap_offload(skb))
+ goto err_vxlan;
+ th = skb_inner_transport_header(skb);
+ } else {
+ th = skb_transport_header(skb);
+ }
+
+ /* compute offset from SOF to transport header and add header len */
+ hdrlen = (th - skb->data) + (((struct tcphdr *)th)->doff << 2);
+
+ first->tx_flags |= FM10K_TX_FLAGS_CSUM;
+
+ /* update gso size and bytecount with header size */
+ first->gso_segs = skb_shinfo(skb)->gso_segs;
+ first->bytecount += (first->gso_segs - 1) * hdrlen;
+
+ /* populate Tx descriptor header size and mss */
+ tx_desc = FM10K_TX_DESC(tx_ring, tx_ring->next_to_use);
+ tx_desc->hdrlen = hdrlen;
+ tx_desc->mss = cpu_to_le16(skb_shinfo(skb)->gso_size);
+
+ return 1;
+err_vxlan:
+ tx_ring->netdev->features &= ~NETIF_F_GSO_UDP_TUNNEL;
+ if (!net_ratelimit())
+ netdev_err(tx_ring->netdev,
+ "TSO requested for unsupported tunnel, disabling offload\n");
+ return -1;
+}
+
+static void fm10k_tx_csum(struct fm10k_ring *tx_ring,
+ struct fm10k_tx_buffer *first)
+{
+ struct sk_buff *skb = first->skb;
+ struct fm10k_tx_desc *tx_desc;
+ union {
+ struct iphdr *ipv4;
+ struct ipv6hdr *ipv6;
+ u8 *raw;
+ } network_hdr;
+ __be16 protocol;
+ u8 l4_hdr = 0;
+
+ if (skb->ip_summed != CHECKSUM_PARTIAL)
+ goto no_csum;
+
+ if (skb->encapsulation) {
+ protocol = fm10k_tx_encap_offload(skb);
+ if (!protocol) {
+ if (skb_checksum_help(skb)) {
+ dev_warn(tx_ring->dev,
+ "failed to offload encap csum!\n");
+ tx_ring->tx_stats.csum_err++;
+ }
+ goto no_csum;
+ }
+ network_hdr.raw = skb_inner_network_header(skb);
+ } else {
+ protocol = vlan_get_protocol(skb);
+ network_hdr.raw = skb_network_header(skb);
+ }
+
+ switch (protocol) {
+ case htons(ETH_P_IP):
+ l4_hdr = network_hdr.ipv4->protocol;
+ break;
+ case htons(ETH_P_IPV6):
+ l4_hdr = network_hdr.ipv6->nexthdr;
+ break;
+ default:
+ if (unlikely(net_ratelimit())) {
+ dev_warn(tx_ring->dev,
+ "partial checksum but ip version=%x!\n",
+ protocol);
+ }
+ tx_ring->tx_stats.csum_err++;
+ goto no_csum;
+ }
+
+ switch (l4_hdr) {
+ case IPPROTO_TCP:
+ case IPPROTO_UDP:
+ break;
+ case IPPROTO_GRE:
+ if (skb->encapsulation)
+ break;
+ default:
+ if (unlikely(net_ratelimit())) {
+ dev_warn(tx_ring->dev,
+ "partial checksum but l4 proto=%x!\n",
+ l4_hdr);
+ }
+ tx_ring->tx_stats.csum_err++;
+ goto no_csum;
+ }
+
+ /* update TX checksum flag */
+ first->tx_flags |= FM10K_TX_FLAGS_CSUM;
+
+no_csum:
+ /* populate Tx descriptor header size and mss */
+ tx_desc = FM10K_TX_DESC(tx_ring, tx_ring->next_to_use);
+ tx_desc->hdrlen = 0;
+ tx_desc->mss = 0;
+}
+
+#define FM10K_SET_FLAG(_input, _flag, _result) \
+ ((_flag <= _result) ? \
+ ((u32)(_input & _flag) * (_result / _flag)) : \
+ ((u32)(_input & _flag) / (_flag / _result)))
+
+static u8 fm10k_tx_desc_flags(struct sk_buff *skb, u32 tx_flags)
+{
+ /* set type for advanced descriptor with frame checksum insertion */
+ u32 desc_flags = 0;
+
+ /* set timestamping bits */
+ if (unlikely(skb_shinfo(skb)->tx_flags & SKBTX_HW_TSTAMP) &&
+ likely(skb_shinfo(skb)->tx_flags & SKBTX_IN_PROGRESS))
+ desc_flags |= FM10K_TXD_FLAG_TIME;
+
+ /* set checksum offload bits */
+ desc_flags |= FM10K_SET_FLAG(tx_flags, FM10K_TX_FLAGS_CSUM,
+ FM10K_TXD_FLAG_CSUM);
+
+ return desc_flags;
+}
+
+static bool fm10k_tx_desc_push(struct fm10k_ring *tx_ring,
+ struct fm10k_tx_desc *tx_desc, u16 i,
+ dma_addr_t dma, unsigned int size, u8 desc_flags)
+{
+ /* set RS and INT for last frame in a cache line */
+ if ((++i & (FM10K_TXD_WB_FIFO_SIZE - 1)) == 0)
+ desc_flags |= FM10K_TXD_FLAG_RS | FM10K_TXD_FLAG_INT;
+
+ /* record values to descriptor */
+ tx_desc->buffer_addr = cpu_to_le64(dma);
+ tx_desc->flags = desc_flags;
+ tx_desc->buflen = cpu_to_le16(size);
+
+ /* return true if we just wrapped the ring */
+ return i == tx_ring->count;
+}
+
+static int __fm10k_maybe_stop_tx(struct fm10k_ring *tx_ring, u16 size)
+{
+ netif_stop_subqueue(tx_ring->netdev, tx_ring->queue_index);
+
+ smp_mb();
+
+ /* We need to check again in a case another CPU has just
+ * made room available. */
+ if (likely(fm10k_desc_unused(tx_ring) < size))
+ return -EBUSY;
+
+ /* A reprieve! - use start_queue because it doesn't call schedule */
+ netif_start_subqueue(tx_ring->netdev, tx_ring->queue_index);
+ ++tx_ring->tx_stats.restart_queue;
+ return 0;
+}
+
+static inline int fm10k_maybe_stop_tx(struct fm10k_ring *tx_ring, u16 size)
+{
+ if (likely(fm10k_desc_unused(tx_ring) >= size))
+ return 0;
+ return __fm10k_maybe_stop_tx(tx_ring, size);
+}
+
+static void fm10k_tx_map(struct fm10k_ring *tx_ring,
+ struct fm10k_tx_buffer *first)
+{
+ struct sk_buff *skb = first->skb;
+ struct fm10k_tx_buffer *tx_buffer;
+ struct fm10k_tx_desc *tx_desc;
+ struct skb_frag_struct *frag;
+ unsigned char *data;
+ dma_addr_t dma;
+ unsigned int data_len, size;
+ u32 tx_flags = first->tx_flags;
+ u16 i = tx_ring->next_to_use;
+ u8 flags = fm10k_tx_desc_flags(skb, tx_flags);
+
+ tx_desc = FM10K_TX_DESC(tx_ring, i);
+
+ /* add HW VLAN tag */
+ if (vlan_tx_tag_present(skb))
+ tx_desc->vlan = cpu_to_le16(vlan_tx_tag_get(skb));
+ else
+ tx_desc->vlan = 0;
+
+ size = skb_headlen(skb);
+ data = skb->data;
+
+ dma = dma_map_single(tx_ring->dev, data, size, DMA_TO_DEVICE);
+
+ data_len = skb->data_len;
+ tx_buffer = first;
+
+ for (frag = &skb_shinfo(skb)->frags[0];; frag++) {
+ if (dma_mapping_error(tx_ring->dev, dma))
+ goto dma_error;
+
+ /* record length, and DMA address */
+ dma_unmap_len_set(tx_buffer, len, size);
+ dma_unmap_addr_set(tx_buffer, dma, dma);
+
+ while (unlikely(size > FM10K_MAX_DATA_PER_TXD)) {
+ if (fm10k_tx_desc_push(tx_ring, tx_desc++, i++, dma,
+ FM10K_MAX_DATA_PER_TXD, flags)) {
+ tx_desc = FM10K_TX_DESC(tx_ring, 0);
+ i = 0;
+ }
+
+ dma += FM10K_MAX_DATA_PER_TXD;
+ size -= FM10K_MAX_DATA_PER_TXD;
+ }
+
+ if (likely(!data_len))
+ break;
+
+ if (fm10k_tx_desc_push(tx_ring, tx_desc++, i++,
+ dma, size, flags)) {
+ tx_desc = FM10K_TX_DESC(tx_ring, 0);
+ i = 0;
+ }
+
+ size = skb_frag_size(frag);
+ data_len -= size;
+
+ dma = skb_frag_dma_map(tx_ring->dev, frag, 0, size,
+ DMA_TO_DEVICE);
+
+ tx_buffer = &tx_ring->tx_buffer[i];
+ }
+
+ /* write last descriptor with LAST bit set */
+ flags |= FM10K_TXD_FLAG_LAST;
+
+ if (fm10k_tx_desc_push(tx_ring, tx_desc, i++, dma, size, flags))
+ i = 0;
+
+ /* record bytecount for BQL */
+ netdev_tx_sent_queue(txring_txq(tx_ring), first->bytecount);
+
+ /* record SW timestamp if HW timestamp is not available */
+ skb_tx_timestamp(first->skb);
+
+ /* Force memory writes to complete before letting h/w know there
+ * are new descriptors to fetch. (Only applicable for weak-ordered
+ * memory model archs, such as IA-64).
+ *
+ * We also need this memory barrier to make certain all of the
+ * status bits have been updated before next_to_watch is written.
+ */
+ wmb();
+
+ /* set next_to_watch value indicating a packet is present */
+ first->next_to_watch = tx_desc;
+
+ tx_ring->next_to_use = i;
+
+ /* Make sure there is space in the ring for the next send. */
+ fm10k_maybe_stop_tx(tx_ring, DESC_NEEDED);
+
+ /* notify HW of packet */
+ if (netif_xmit_stopped(txring_txq(tx_ring)) || !skb->xmit_more) {
+ writel(i, tx_ring->tail);
+
+ /* we need this if more than one processor can write to our tail
+ * at a time, it synchronizes IO on IA64/Altix systems
+ */
+ mmiowb();
+ }
+
+ return;
+dma_error:
+ dev_err(tx_ring->dev, "TX DMA map failed\n");
+
+ /* clear dma mappings for failed tx_buffer map */
+ for (;;) {
+ tx_buffer = &tx_ring->tx_buffer[i];
+ fm10k_unmap_and_free_tx_resource(tx_ring, tx_buffer);
+ if (tx_buffer == first)
+ break;
+ if (i == 0)
+ i = tx_ring->count;
+ i--;
+ }
+
+ tx_ring->next_to_use = i;
+}
+
+netdev_tx_t fm10k_xmit_frame_ring(struct sk_buff *skb,
+ struct fm10k_ring *tx_ring)
+{
+ struct fm10k_tx_buffer *first;
+ int tso;
+ u32 tx_flags = 0;
+#if PAGE_SIZE > FM10K_MAX_DATA_PER_TXD
+ unsigned short f;
+#endif
+ u16 count = TXD_USE_COUNT(skb_headlen(skb));
+
+ /* need: 1 descriptor per page * PAGE_SIZE/FM10K_MAX_DATA_PER_TXD,
+ * + 1 desc for skb_headlen/FM10K_MAX_DATA_PER_TXD,
+ * + 2 desc gap to keep tail from touching head
+ * otherwise try next time
+ */
+#if PAGE_SIZE > FM10K_MAX_DATA_PER_TXD
+ for (f = 0; f < skb_shinfo(skb)->nr_frags; f++)
+ count += TXD_USE_COUNT(skb_shinfo(skb)->frags[f].size);
+#else
+ count += skb_shinfo(skb)->nr_frags;
+#endif
+ if (fm10k_maybe_stop_tx(tx_ring, count + 3)) {
+ tx_ring->tx_stats.tx_busy++;
+ return NETDEV_TX_BUSY;
+ }
+
+ /* record the location of the first descriptor for this packet */
+ first = &tx_ring->tx_buffer[tx_ring->next_to_use];
+ first->skb = skb;
+ first->bytecount = max_t(unsigned int, skb->len, ETH_ZLEN);
+ first->gso_segs = 1;
+
+ /* record initial flags and protocol */
+ first->tx_flags = tx_flags;
+
+ tso = fm10k_tso(tx_ring, first);
+ if (tso < 0)
+ goto out_drop;
+ else if (!tso)
+ fm10k_tx_csum(tx_ring, first);
+
+ fm10k_tx_map(tx_ring, first);
+
+ return NETDEV_TX_OK;
+
+out_drop:
+ dev_kfree_skb_any(first->skb);
+ first->skb = NULL;
+
+ return NETDEV_TX_OK;
+}
+
+static u64 fm10k_get_tx_completed(struct fm10k_ring *ring)
+{
+ return ring->stats.packets;
+}
+
+static u64 fm10k_get_tx_pending(struct fm10k_ring *ring)
+{
+ /* use SW head and tail until we have real hardware */
+ u32 head = ring->next_to_clean;
+ u32 tail = ring->next_to_use;
+
+ return ((head <= tail) ? tail : tail + ring->count) - head;
+}
+
+bool fm10k_check_tx_hang(struct fm10k_ring *tx_ring)
+{
+ u32 tx_done = fm10k_get_tx_completed(tx_ring);
+ u32 tx_done_old = tx_ring->tx_stats.tx_done_old;
+ u32 tx_pending = fm10k_get_tx_pending(tx_ring);
+
+ clear_check_for_tx_hang(tx_ring);
+
+ /* Check for a hung queue, but be thorough. This verifies
+ * that a transmit has been completed since the previous
+ * check AND there is at least one packet pending. By
+ * requiring this to fail twice we avoid races with
+ * clearing the ARMED bit and conditions where we
+ * run the check_tx_hang logic with a transmit completion
+ * pending but without time to complete it yet.
+ */
+ if (!tx_pending || (tx_done_old != tx_done)) {
+ /* update completed stats and continue */
+ tx_ring->tx_stats.tx_done_old = tx_done;
+ /* reset the countdown */
+ clear_bit(__FM10K_HANG_CHECK_ARMED, &tx_ring->state);
+
+ return false;
+ }
+
+ /* make sure it is true for two checks in a row */
+ return test_and_set_bit(__FM10K_HANG_CHECK_ARMED, &tx_ring->state);
+}
+
+/**
+ * fm10k_tx_timeout_reset - initiate reset due to Tx timeout
+ * @interface: driver private struct
+ **/
+void fm10k_tx_timeout_reset(struct fm10k_intfc *interface)
+{
+ /* Do the reset outside of interrupt context */
+ if (!test_bit(__FM10K_DOWN, &interface->state)) {
+ netdev_err(interface->netdev, "Reset interface\n");
+ interface->tx_timeout_count++;
+ interface->flags |= FM10K_FLAG_RESET_REQUESTED;
+ fm10k_service_event_schedule(interface);
+ }
+}
+
+/**
+ * fm10k_clean_tx_irq - Reclaim resources after transmit completes
+ * @q_vector: structure containing interrupt and ring information
+ * @tx_ring: tx ring to clean
+ **/
+static bool fm10k_clean_tx_irq(struct fm10k_q_vector *q_vector,
+ struct fm10k_ring *tx_ring)
+{
+ struct fm10k_intfc *interface = q_vector->interface;
+ struct fm10k_tx_buffer *tx_buffer;
+ struct fm10k_tx_desc *tx_desc;
+ unsigned int total_bytes = 0, total_packets = 0;
+ unsigned int budget = q_vector->tx.work_limit;
+ unsigned int i = tx_ring->next_to_clean;
+
+ if (test_bit(__FM10K_DOWN, &interface->state))
+ return true;
+
+ tx_buffer = &tx_ring->tx_buffer[i];
+ tx_desc = FM10K_TX_DESC(tx_ring, i);
+ i -= tx_ring->count;
+
+ do {
+ struct fm10k_tx_desc *eop_desc = tx_buffer->next_to_watch;
+
+ /* if next_to_watch is not set then there is no work pending */
+ if (!eop_desc)
+ break;
+
+ /* prevent any other reads prior to eop_desc */
+ read_barrier_depends();
+
+ /* if DD is not set pending work has not been completed */
+ if (!(eop_desc->flags & FM10K_TXD_FLAG_DONE))
+ break;
+
+ /* clear next_to_watch to prevent false hangs */
+ tx_buffer->next_to_watch = NULL;
+
+ /* update the statistics for this packet */
+ total_bytes += tx_buffer->bytecount;
+ total_packets += tx_buffer->gso_segs;
+
+ /* free the skb */
+ dev_consume_skb_any(tx_buffer->skb);
+
+ /* unmap skb header data */
+ dma_unmap_single(tx_ring->dev,
+ dma_unmap_addr(tx_buffer, dma),
+ dma_unmap_len(tx_buffer, len),
+ DMA_TO_DEVICE);
+
+ /* clear tx_buffer data */
+ tx_buffer->skb = NULL;
+ dma_unmap_len_set(tx_buffer, len, 0);
+
+ /* unmap remaining buffers */
+ while (tx_desc != eop_desc) {
+ tx_buffer++;
+ tx_desc++;
+ i++;
+ if (unlikely(!i)) {
+ i -= tx_ring->count;
+ tx_buffer = tx_ring->tx_buffer;
+ tx_desc = FM10K_TX_DESC(tx_ring, 0);
+ }
+
+ /* unmap any remaining paged data */
+ if (dma_unmap_len(tx_buffer, len)) {
+ dma_unmap_page(tx_ring->dev,
+ dma_unmap_addr(tx_buffer, dma),
+ dma_unmap_len(tx_buffer, len),
+ DMA_TO_DEVICE);
+ dma_unmap_len_set(tx_buffer, len, 0);
+ }
+ }
+
+ /* move us one more past the eop_desc for start of next pkt */
+ tx_buffer++;
+ tx_desc++;
+ i++;
+ if (unlikely(!i)) {
+ i -= tx_ring->count;
+ tx_buffer = tx_ring->tx_buffer;
+ tx_desc = FM10K_TX_DESC(tx_ring, 0);
+ }
+
+ /* issue prefetch for next Tx descriptor */
+ prefetch(tx_desc);
+
+ /* update budget accounting */
+ budget--;
+ } while (likely(budget));
+
+ i += tx_ring->count;
+ tx_ring->next_to_clean = i;
+ u64_stats_update_begin(&tx_ring->syncp);
+ tx_ring->stats.bytes += total_bytes;
+ tx_ring->stats.packets += total_packets;
+ u64_stats_update_end(&tx_ring->syncp);
+ q_vector->tx.total_bytes += total_bytes;
+ q_vector->tx.total_packets += total_packets;
+
+ if (check_for_tx_hang(tx_ring) && fm10k_check_tx_hang(tx_ring)) {
+ /* schedule immediate reset if we believe we hung */
+ struct fm10k_hw *hw = &interface->hw;
+
+ netif_err(interface, drv, tx_ring->netdev,
+ "Detected Tx Unit Hang\n"
+ " Tx Queue <%d>\n"
+ " TDH, TDT <%x>, <%x>\n"
+ " next_to_use <%x>\n"
+ " next_to_clean <%x>\n",
+ tx_ring->queue_index,
+ fm10k_read_reg(hw, FM10K_TDH(tx_ring->reg_idx)),
+ fm10k_read_reg(hw, FM10K_TDT(tx_ring->reg_idx)),
+ tx_ring->next_to_use, i);
+
+ netif_stop_subqueue(tx_ring->netdev,
+ tx_ring->queue_index);
+
+ netif_info(interface, probe, tx_ring->netdev,
+ "tx hang %d detected on queue %d, resetting interface\n",
+ interface->tx_timeout_count + 1,
+ tx_ring->queue_index);
+
+ fm10k_tx_timeout_reset(interface);
+
+ /* the netdev is about to reset, no point in enabling stuff */
+ return true;
+ }
+
+ /* notify netdev of completed buffers */
+ netdev_tx_completed_queue(txring_txq(tx_ring),
+ total_packets, total_bytes);
+
+#define TX_WAKE_THRESHOLD min_t(u16, FM10K_MIN_TXD - 1, DESC_NEEDED * 2)
+ if (unlikely(total_packets && netif_carrier_ok(tx_ring->netdev) &&
+ (fm10k_desc_unused(tx_ring) >= TX_WAKE_THRESHOLD))) {
+ /* Make sure that anybody stopping the queue after this
+ * sees the new next_to_clean.
+ */
+ smp_mb();
+ if (__netif_subqueue_stopped(tx_ring->netdev,
+ tx_ring->queue_index) &&
+ !test_bit(__FM10K_DOWN, &interface->state)) {
+ netif_wake_subqueue(tx_ring->netdev,
+ tx_ring->queue_index);
+ ++tx_ring->tx_stats.restart_queue;
+ }
+ }
+
+ return !!budget;
+}
+
+/**
+ * fm10k_update_itr - update the dynamic ITR value based on packet size
+ *
+ * Stores a new ITR value based on strictly on packet size. The
+ * divisors and thresholds used by this function were determined based
+ * on theoretical maximum wire speed and testing data, in order to
+ * minimize response time while increasing bulk throughput.
+ *
+ * @ring_container: Container for rings to have ITR updated
+ **/
+static void fm10k_update_itr(struct fm10k_ring_container *ring_container)
+{
+ unsigned int avg_wire_size, packets;
+
+ /* Only update ITR if we are using adaptive setting */
+ if (!(ring_container->itr & FM10K_ITR_ADAPTIVE))
+ goto clear_counts;
+
+ packets = ring_container->total_packets;
+ if (!packets)
+ goto clear_counts;
+
+ avg_wire_size = ring_container->total_bytes / packets;
+
+ /* Add 24 bytes to size to account for CRC, preamble, and gap */
+ avg_wire_size += 24;
+
+ /* Don't starve jumbo frames */
+ if (avg_wire_size > 3000)
+ avg_wire_size = 3000;
+
+ /* Give a little boost to mid-size frames */
+ if ((avg_wire_size > 300) && (avg_wire_size < 1200))
+ avg_wire_size /= 3;
+ else
+ avg_wire_size /= 2;
+
+ /* write back value and retain adaptive flag */
+ ring_container->itr = avg_wire_size | FM10K_ITR_ADAPTIVE;
+
+clear_counts:
+ ring_container->total_bytes = 0;
+ ring_container->total_packets = 0;
+}
+
+static void fm10k_qv_enable(struct fm10k_q_vector *q_vector)
+{
+ /* Enable auto-mask and clear the current mask */
+ u32 itr = FM10K_ITR_ENABLE;
+
+ /* Update Tx ITR */
+ fm10k_update_itr(&q_vector->tx);
+
+ /* Update Rx ITR */
+ fm10k_update_itr(&q_vector->rx);
+
+ /* Store Tx itr in timer slot 0 */
+ itr |= (q_vector->tx.itr & FM10K_ITR_MAX);
+
+ /* Shift Rx itr to timer slot 1 */
+ itr |= (q_vector->rx.itr & FM10K_ITR_MAX) << FM10K_ITR_INTERVAL1_SHIFT;
+
+ /* Write the final value to the ITR register */
+ writel(itr, q_vector->itr);
+}
+
+static int fm10k_poll(struct napi_struct *napi, int budget)
+{
+ struct fm10k_q_vector *q_vector =
+ container_of(napi, struct fm10k_q_vector, napi);
+ struct fm10k_ring *ring;
+ int per_ring_budget;
+ bool clean_complete = true;
+
+ fm10k_for_each_ring(ring, q_vector->tx)
+ clean_complete &= fm10k_clean_tx_irq(q_vector, ring);
+
+ /* attempt to distribute budget to each queue fairly, but don't
+ * allow the budget to go below 1 because we'll exit polling
+ */
+ if (q_vector->rx.count > 1)
+ per_ring_budget = max(budget/q_vector->rx.count, 1);
+ else
+ per_ring_budget = budget;
+
+ fm10k_for_each_ring(ring, q_vector->rx)
+ clean_complete &= fm10k_clean_rx_irq(q_vector, ring,
+ per_ring_budget);
+
+ /* If all work not completed, return budget and keep polling */
+ if (!clean_complete)
+ return budget;
+
+ /* all work done, exit the polling mode */
+ napi_complete(napi);
+
+ /* re-enable the q_vector */
+ fm10k_qv_enable(q_vector);
+
+ return 0;
+}
+
+/**
+ * fm10k_set_qos_queues: Allocate queues for a QOS-enabled device
+ * @interface: board private structure to initialize
+ *
+ * When QoS (Quality of Service) is enabled, allocate queues for
+ * each traffic class. If multiqueue isn't available,then abort QoS
+ * initialization.
+ *
+ * This function handles all combinations of Qos and RSS.
+ *
+ **/
+static bool fm10k_set_qos_queues(struct fm10k_intfc *interface)
+{
+ struct net_device *dev = interface->netdev;
+ struct fm10k_ring_feature *f;
+ int rss_i, i;
+ int pcs;
+
+ /* Map queue offset and counts onto allocated tx queues */
+ pcs = netdev_get_num_tc(dev);
+
+ if (pcs <= 1)
+ return false;
+
+ /* set QoS mask and indices */
+ f = &interface->ring_feature[RING_F_QOS];
+ f->indices = pcs;
+ f->mask = (1 << fls(pcs - 1)) - 1;
+
+ /* determine the upper limit for our current DCB mode */
+ rss_i = interface->hw.mac.max_queues / pcs;
+ rss_i = 1 << (fls(rss_i) - 1);
+
+ /* set RSS mask and indices */
+ f = &interface->ring_feature[RING_F_RSS];
+ rss_i = min_t(u16, rss_i, f->limit);
+ f->indices = rss_i;
+ f->mask = (1 << fls(rss_i - 1)) - 1;
+
+ /* configure pause class to queue mapping */
+ for (i = 0; i < pcs; i++)
+ netdev_set_tc_queue(dev, i, rss_i, rss_i * i);
+
+ interface->num_rx_queues = rss_i * pcs;
+ interface->num_tx_queues = rss_i * pcs;
+
+ return true;
+}
+
+/**
+ * fm10k_set_rss_queues: Allocate queues for RSS
+ * @interface: board private structure to initialize
+ *
+ * This is our "base" multiqueue mode. RSS (Receive Side Scaling) will try
+ * to allocate one Rx queue per CPU, and if available, one Tx queue per CPU.
+ *
+ **/
+static bool fm10k_set_rss_queues(struct fm10k_intfc *interface)
+{
+ struct fm10k_ring_feature *f;
+ u16 rss_i;
+
+ f = &interface->ring_feature[RING_F_RSS];
+ rss_i = min_t(u16, interface->hw.mac.max_queues, f->limit);
+
+ /* record indices and power of 2 mask for RSS */
+ f->indices = rss_i;
+ f->mask = (1 << fls(rss_i - 1)) - 1;
+
+ interface->num_rx_queues = rss_i;
+ interface->num_tx_queues = rss_i;
+
+ return true;
+}
+
+/**
+ * fm10k_set_num_queues: Allocate queues for device, feature dependent
+ * @interface: board private structure to initialize
+ *
+ * This is the top level queue allocation routine. The order here is very
+ * important, starting with the "most" number of features turned on at once,
+ * and ending with the smallest set of features. This way large combinations
+ * can be allocated if they're turned on, and smaller combinations are the
+ * fallthrough conditions.
+ *
+ **/
+static void fm10k_set_num_queues(struct fm10k_intfc *interface)
+{
+ /* Start with base case */
+ interface->num_rx_queues = 1;
+ interface->num_tx_queues = 1;
+
+ if (fm10k_set_qos_queues(interface))
+ return;
+
+ fm10k_set_rss_queues(interface);
+}
+
+/**
+ * fm10k_alloc_q_vector - Allocate memory for a single interrupt vector
+ * @interface: board private structure to initialize
+ * @v_count: q_vectors allocated on interface, used for ring interleaving
+ * @v_idx: index of vector in interface struct
+ * @txr_count: total number of Tx rings to allocate
+ * @txr_idx: index of first Tx ring to allocate
+ * @rxr_count: total number of Rx rings to allocate
+ * @rxr_idx: index of first Rx ring to allocate
+ *
+ * We allocate one q_vector. If allocation fails we return -ENOMEM.
+ **/
+static int fm10k_alloc_q_vector(struct fm10k_intfc *interface,
+ unsigned int v_count, unsigned int v_idx,
+ unsigned int txr_count, unsigned int txr_idx,
+ unsigned int rxr_count, unsigned int rxr_idx)
+{
+ struct fm10k_q_vector *q_vector;
+ struct fm10k_ring *ring;
+ int ring_count, size;
+
+ ring_count = txr_count + rxr_count;
+ size = sizeof(struct fm10k_q_vector) +
+ (sizeof(struct fm10k_ring) * ring_count);
+
+ /* allocate q_vector and rings */
+ q_vector = kzalloc(size, GFP_KERNEL);
+ if (!q_vector)
+ return -ENOMEM;
+
+ /* initialize NAPI */
+ netif_napi_add(interface->netdev, &q_vector->napi,
+ fm10k_poll, NAPI_POLL_WEIGHT);
+
+ /* tie q_vector and interface together */
+ interface->q_vector[v_idx] = q_vector;
+ q_vector->interface = interface;
+ q_vector->v_idx = v_idx;
+
+ /* initialize pointer to rings */
+ ring = q_vector->ring;
+
+ /* save Tx ring container info */
+ q_vector->tx.ring = ring;
+ q_vector->tx.work_limit = FM10K_DEFAULT_TX_WORK;
+ q_vector->tx.itr = interface->tx_itr;
+ q_vector->tx.count = txr_count;
+
+ while (txr_count) {
+ /* assign generic ring traits */
+ ring->dev = &interface->pdev->dev;
+ ring->netdev = interface->netdev;
+
+ /* configure backlink on ring */
+ ring->q_vector = q_vector;
+
+ /* apply Tx specific ring traits */
+ ring->count = interface->tx_ring_count;
+ ring->queue_index = txr_idx;
+
+ /* assign ring to interface */
+ interface->tx_ring[txr_idx] = ring;
+
+ /* update count and index */
+ txr_count--;
+ txr_idx += v_count;
+
+ /* push pointer to next ring */
+ ring++;
+ }
+
+ /* save Rx ring container info */
+ q_vector->rx.ring = ring;
+ q_vector->rx.itr = interface->rx_itr;
+ q_vector->rx.count = rxr_count;
+
+ while (rxr_count) {
+ /* assign generic ring traits */
+ ring->dev = &interface->pdev->dev;
+ ring->netdev = interface->netdev;
+ rcu_assign_pointer(ring->l2_accel, interface->l2_accel);
+
+ /* configure backlink on ring */
+ ring->q_vector = q_vector;
+
+ /* apply Rx specific ring traits */
+ ring->count = interface->rx_ring_count;
+ ring->queue_index = rxr_idx;
+
+ /* assign ring to interface */
+ interface->rx_ring[rxr_idx] = ring;
+
+ /* update count and index */
+ rxr_count--;
+ rxr_idx += v_count;
+
+ /* push pointer to next ring */
+ ring++;
+ }
+
+ fm10k_dbg_q_vector_init(q_vector);
+
+ return 0;
+}
+
+/**
+ * fm10k_free_q_vector - Free memory allocated for specific interrupt vector
+ * @interface: board private structure to initialize
+ * @v_idx: Index of vector to be freed
+ *
+ * This function frees the memory allocated to the q_vector. In addition if
+ * NAPI is enabled it will delete any references to the NAPI struct prior
+ * to freeing the q_vector.
+ **/
+static void fm10k_free_q_vector(struct fm10k_intfc *interface, int v_idx)
+{
+ struct fm10k_q_vector *q_vector = interface->q_vector[v_idx];
+ struct fm10k_ring *ring;
+
+ fm10k_dbg_q_vector_exit(q_vector);
+
+ fm10k_for_each_ring(ring, q_vector->tx)
+ interface->tx_ring[ring->queue_index] = NULL;
+
+ fm10k_for_each_ring(ring, q_vector->rx)
+ interface->rx_ring[ring->queue_index] = NULL;
+
+ interface->q_vector[v_idx] = NULL;
+ netif_napi_del(&q_vector->napi);
+ kfree_rcu(q_vector, rcu);
+}
+
+/**
+ * fm10k_alloc_q_vectors - Allocate memory for interrupt vectors
+ * @interface: board private structure to initialize
+ *
+ * We allocate one q_vector per queue interrupt. If allocation fails we
+ * return -ENOMEM.
+ **/
+static int fm10k_alloc_q_vectors(struct fm10k_intfc *interface)
+{
+ unsigned int q_vectors = interface->num_q_vectors;
+ unsigned int rxr_remaining = interface->num_rx_queues;
+ unsigned int txr_remaining = interface->num_tx_queues;
+ unsigned int rxr_idx = 0, txr_idx = 0, v_idx = 0;
+ int err;
+
+ if (q_vectors >= (rxr_remaining + txr_remaining)) {
+ for (; rxr_remaining; v_idx++) {
+ err = fm10k_alloc_q_vector(interface, q_vectors, v_idx,
+ 0, 0, 1, rxr_idx);
+ if (err)
+ goto err_out;
+
+ /* update counts and index */
+ rxr_remaining--;
+ rxr_idx++;
+ }
+ }
+
+ for (; v_idx < q_vectors; v_idx++) {
+ int rqpv = DIV_ROUND_UP(rxr_remaining, q_vectors - v_idx);
+ int tqpv = DIV_ROUND_UP(txr_remaining, q_vectors - v_idx);
+
+ err = fm10k_alloc_q_vector(interface, q_vectors, v_idx,
+ tqpv, txr_idx,
+ rqpv, rxr_idx);
+
+ if (err)
+ goto err_out;
+
+ /* update counts and index */
+ rxr_remaining -= rqpv;
+ txr_remaining -= tqpv;
+ rxr_idx++;
+ txr_idx++;
+ }
+
+ return 0;
+
+err_out:
+ interface->num_tx_queues = 0;
+ interface->num_rx_queues = 0;
+ interface->num_q_vectors = 0;
+
+ while (v_idx--)
+ fm10k_free_q_vector(interface, v_idx);
+
+ return -ENOMEM;
+}
+
+/**
+ * fm10k_free_q_vectors - Free memory allocated for interrupt vectors
+ * @interface: board private structure to initialize
+ *
+ * This function frees the memory allocated to the q_vectors. In addition if
+ * NAPI is enabled it will delete any references to the NAPI struct prior
+ * to freeing the q_vector.
+ **/
+static void fm10k_free_q_vectors(struct fm10k_intfc *interface)
+{
+ int v_idx = interface->num_q_vectors;
+
+ interface->num_tx_queues = 0;
+ interface->num_rx_queues = 0;
+ interface->num_q_vectors = 0;
+
+ while (v_idx--)
+ fm10k_free_q_vector(interface, v_idx);
+}
+
+/**
+ * f10k_reset_msix_capability - reset MSI-X capability
+ * @interface: board private structure to initialize
+ *
+ * Reset the MSI-X capability back to its starting state
+ **/
+static void fm10k_reset_msix_capability(struct fm10k_intfc *interface)
+{
+ pci_disable_msix(interface->pdev);
+ kfree(interface->msix_entries);
+ interface->msix_entries = NULL;
+}
+
+/**
+ * f10k_init_msix_capability - configure MSI-X capability
+ * @interface: board private structure to initialize
+ *
+ * Attempt to configure the interrupts using the best available
+ * capabilities of the hardware and the kernel.
+ **/
+static int fm10k_init_msix_capability(struct fm10k_intfc *interface)
+{
+ struct fm10k_hw *hw = &interface->hw;
+ int v_budget, vector;
+
+ /* It's easy to be greedy for MSI-X vectors, but it really
+ * doesn't do us much good if we have a lot more vectors
+ * than CPU's. So let's be conservative and only ask for
+ * (roughly) the same number of vectors as there are CPU's.
+ * the default is to use pairs of vectors
+ */
+ v_budget = max(interface->num_rx_queues, interface->num_tx_queues);
+ v_budget = min_t(u16, v_budget, num_online_cpus());
+
+ /* account for vectors not related to queues */
+ v_budget += NON_Q_VECTORS(hw);
+
+ /* At the same time, hardware can only support a maximum of
+ * hw.mac->max_msix_vectors vectors. With features
+ * such as RSS and VMDq, we can easily surpass the number of Rx and Tx
+ * descriptor queues supported by our device. Thus, we cap it off in
+ * those rare cases where the cpu count also exceeds our vector limit.
+ */
+ v_budget = min_t(int, v_budget, hw->mac.max_msix_vectors);
+
+ /* A failure in MSI-X entry allocation is fatal. */
+ interface->msix_entries = kcalloc(v_budget, sizeof(struct msix_entry),
+ GFP_KERNEL);
+ if (!interface->msix_entries)
+ return -ENOMEM;
+
+ /* populate entry values */
+ for (vector = 0; vector < v_budget; vector++)
+ interface->msix_entries[vector].entry = vector;
+
+ /* Attempt to enable MSI-X with requested value */
+ v_budget = pci_enable_msix_range(interface->pdev,
+ interface->msix_entries,
+ MIN_MSIX_COUNT(hw),
+ v_budget);
+ if (v_budget < 0) {
+ kfree(interface->msix_entries);
+ interface->msix_entries = NULL;
+ return -ENOMEM;
+ }
+
+ /* record the number of queues available for q_vectors */
+ interface->num_q_vectors = v_budget - NON_Q_VECTORS(hw);
+
+ return 0;
+}
+
+/**
+ * fm10k_cache_ring_qos - Descriptor ring to register mapping for QoS
+ * @interface: Interface structure continaining rings and devices
+ *
+ * Cache the descriptor ring offsets for Qos
+ **/
+static bool fm10k_cache_ring_qos(struct fm10k_intfc *interface)
+{
+ struct net_device *dev = interface->netdev;
+ int pc, offset, rss_i, i, q_idx;
+ u16 pc_stride = interface->ring_feature[RING_F_QOS].mask + 1;
+ u8 num_pcs = netdev_get_num_tc(dev);
+
+ if (num_pcs <= 1)
+ return false;
+
+ rss_i = interface->ring_feature[RING_F_RSS].indices;
+
+ for (pc = 0, offset = 0; pc < num_pcs; pc++, offset += rss_i) {
+ q_idx = pc;
+ for (i = 0; i < rss_i; i++) {
+ interface->tx_ring[offset + i]->reg_idx = q_idx;
+ interface->tx_ring[offset + i]->qos_pc = pc;
+ interface->rx_ring[offset + i]->reg_idx = q_idx;
+ interface->rx_ring[offset + i]->qos_pc = pc;
+ q_idx += pc_stride;
+ }
+ }
+
+ return true;
+}
+
+/**
+ * fm10k_cache_ring_rss - Descriptor ring to register mapping for RSS
+ * @interface: Interface structure continaining rings and devices
+ *
+ * Cache the descriptor ring offsets for RSS
+ **/
+static void fm10k_cache_ring_rss(struct fm10k_intfc *interface)
+{
+ int i;
+
+ for (i = 0; i < interface->num_rx_queues; i++)
+ interface->rx_ring[i]->reg_idx = i;
+
+ for (i = 0; i < interface->num_tx_queues; i++)
+ interface->tx_ring[i]->reg_idx = i;
+}
+
+/**
+ * fm10k_assign_rings - Map rings to network devices
+ * @interface: Interface structure containing rings and devices
+ *
+ * This function is meant to go though and configure both the network
+ * devices so that they contain rings, and configure the rings so that
+ * they function with their network devices.
+ **/
+static void fm10k_assign_rings(struct fm10k_intfc *interface)
+{
+ if (fm10k_cache_ring_qos(interface))
+ return;
+
+ fm10k_cache_ring_rss(interface);
+}
+
+static void fm10k_init_reta(struct fm10k_intfc *interface)
+{
+ u16 i, rss_i = interface->ring_feature[RING_F_RSS].indices;
+ u32 reta, base;
+
+ /* If the netdev is initialized we have to maintain table if possible */
+ if (interface->netdev->reg_state) {
+ for (i = FM10K_RETA_SIZE; i--;) {
+ reta = interface->reta[i];
+ if ((((reta << 24) >> 24) < rss_i) &&
+ (((reta << 16) >> 24) < rss_i) &&
+ (((reta << 8) >> 24) < rss_i) &&
+ (((reta) >> 24) < rss_i))
+ continue;
+ goto repopulate_reta;
+ }
+
+ /* do nothing if all of the elements are in bounds */
+ return;
+ }
+
+repopulate_reta:
+ /* Populate the redirection table 4 entries at a time. To do this
+ * we are generating the results for n and n+2 and then interleaving
+ * those with the results with n+1 and n+3.
+ */
+ for (i = FM10K_RETA_SIZE; i--;) {
+ /* first pass generates n and n+2 */
+ base = ((i * 0x00040004) + 0x00020000) * rss_i;
+ reta = (base & 0x3F803F80) >> 7;
+
+ /* second pass generates n+1 and n+3 */
+ base += 0x00010001 * rss_i;
+ reta |= (base & 0x3F803F80) << 1;
+
+ interface->reta[i] = reta;
+ }
+}
+
+/**
+ * fm10k_init_queueing_scheme - Determine proper queueing scheme
+ * @interface: board private structure to initialize
+ *
+ * We determine which queueing scheme to use based on...
+ * - Hardware queue count (num_*_queues)
+ * - defined by miscellaneous hardware support/features (RSS, etc.)
+ **/
+int fm10k_init_queueing_scheme(struct fm10k_intfc *interface)
+{
+ int err;
+
+ /* Number of supported queues */
+ fm10k_set_num_queues(interface);
+
+ /* Configure MSI-X capability */
+ err = fm10k_init_msix_capability(interface);
+ if (err) {
+ dev_err(&interface->pdev->dev,
+ "Unable to initialize MSI-X capability\n");
+ return err;
+ }
+
+ /* Allocate memory for queues */
+ err = fm10k_alloc_q_vectors(interface);
+ if (err)
+ return err;
+
+ /* Map rings to devices, and map devices to physical queues */
+ fm10k_assign_rings(interface);
+
+ /* Initialize RSS redirection table */
+ fm10k_init_reta(interface);
+
+ return 0;
+}
+
+/**
+ * fm10k_clear_queueing_scheme - Clear the current queueing scheme settings
+ * @interface: board private structure to clear queueing scheme on
+ *
+ * We go through and clear queueing specific resources and reset the structure
+ * to pre-load conditions
+ **/
+void fm10k_clear_queueing_scheme(struct fm10k_intfc *interface)
+{
+ fm10k_free_q_vectors(interface);
+ fm10k_reset_msix_capability(interface);
+}