Skip to content

Commit

Permalink
sfc: move common tx code
Browse files Browse the repository at this point in the history 
Once again, a tiny bit of refactoring was required to stitch the code
together (i.e. adding headers). The moved code deals with managing tx
queues and mappings.

Signed-off-by: Alexandru-Mihai Maftei <amaftei@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
  • Loading branch information
Alex Maftei (amaftei) authored and David S. Miller committed Jan 8, 2020
1 parent 1751cc3 commit 17d3b21
Show file tree
Hide file tree
Showing 3 changed files with 311 additions and 296 deletions.
2 changes: 1 addition & 1 deletion drivers/net/ethernet/sfc/Makefile
View file
Original file line number Diff line number Diff line change
@@ -1,7 +1,7 @@
# SPDX-License-Identifier: GPL-2.0
sfc-y += efx.o efx_common.o efx_channels.o nic.o \
farch.o siena.o ef10.o \
tx.o rx.o rx_common.o \
tx.o tx_common.o rx.o rx_common.o \
selftest.o ethtool.o ptp.o tx_tso.o \
mcdi.o mcdi_port.o \
mcdi_mon.o
Expand Down
295 changes: 0 additions & 295 deletions drivers/net/ethernet/sfc/tx.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -57,72 +57,6 @@ u8 *efx_tx_get_copy_buffer_limited(struct efx_tx_queue *tx_queue,
return efx_tx_get_copy_buffer(tx_queue, buffer);
}

void efx_dequeue_buffer(struct efx_tx_queue *tx_queue,
struct efx_tx_buffer *buffer,
unsigned int *pkts_compl,
unsigned int *bytes_compl)
{
if (buffer->unmap_len) {
struct device *dma_dev = &tx_queue->efx->pci_dev->dev;
dma_addr_t unmap_addr = buffer->dma_addr - buffer->dma_offset;
if (buffer->flags & EFX_TX_BUF_MAP_SINGLE)
dma_unmap_single(dma_dev, unmap_addr, buffer->unmap_len,
DMA_TO_DEVICE);
else
dma_unmap_page(dma_dev, unmap_addr, buffer->unmap_len,
DMA_TO_DEVICE);
buffer->unmap_len = 0;
}

if (buffer->flags & EFX_TX_BUF_SKB) {
struct sk_buff *skb = (struct sk_buff *)buffer->skb;

EFX_WARN_ON_PARANOID(!pkts_compl || !bytes_compl);
(*pkts_compl)++;
(*bytes_compl) += skb->len;
if (tx_queue->timestamping &&
(tx_queue->completed_timestamp_major ||
tx_queue->completed_timestamp_minor)) {
struct skb_shared_hwtstamps hwtstamp;

hwtstamp.hwtstamp =
efx_ptp_nic_to_kernel_time(tx_queue);
skb_tstamp_tx(skb, &hwtstamp);

tx_queue->completed_timestamp_major = 0;
tx_queue->completed_timestamp_minor = 0;
}
dev_consume_skb_any((struct sk_buff *)buffer->skb);
netif_vdbg(tx_queue->efx, tx_done, tx_queue->efx->net_dev,
"TX queue %d transmission id %x complete\n",
tx_queue->queue, tx_queue->read_count);
} else if (buffer->flags & EFX_TX_BUF_XDP) {
xdp_return_frame_rx_napi(buffer->xdpf);
}

buffer->len = 0;
buffer->flags = 0;
}

unsigned int efx_tx_max_skb_descs(struct efx_nic *efx)
{
/* Header and payload descriptor for each output segment, plus
* one for every input fragment boundary within a segment
*/
unsigned int max_descs = EFX_TSO_MAX_SEGS * 2 + MAX_SKB_FRAGS;

/* Possibly one more per segment for option descriptors */
if (efx_nic_rev(efx) >= EFX_REV_HUNT_A0)
max_descs += EFX_TSO_MAX_SEGS;

/* Possibly more for PCIe page boundaries within input fragments */
if (PAGE_SIZE > EFX_PAGE_SIZE)
max_descs += max_t(unsigned int, MAX_SKB_FRAGS,
DIV_ROUND_UP(GSO_MAX_SIZE, EFX_PAGE_SIZE));

return max_descs;
}

static void efx_tx_maybe_stop_queue(struct efx_tx_queue *txq1)
{
/* We need to consider both queues that the net core sees as one */
Expand Down Expand Up @@ -334,107 +268,6 @@ static int efx_enqueue_skb_pio(struct efx_tx_queue *tx_queue,
}
#endif /* EFX_USE_PIO */

struct efx_tx_buffer *efx_tx_map_chunk(struct efx_tx_queue *tx_queue,
dma_addr_t dma_addr,
size_t len)
{
const struct efx_nic_type *nic_type = tx_queue->efx->type;
struct efx_tx_buffer *buffer;
unsigned int dma_len;

/* Map the fragment taking account of NIC-dependent DMA limits. */
do {
buffer = efx_tx_queue_get_insert_buffer(tx_queue);
dma_len = nic_type->tx_limit_len(tx_queue, dma_addr, len);

buffer->len = dma_len;
buffer->dma_addr = dma_addr;
buffer->flags = EFX_TX_BUF_CONT;
len -= dma_len;
dma_addr += dma_len;
++tx_queue->insert_count;
} while (len);

return buffer;
}

/* Map all data from an SKB for DMA and create descriptors on the queue.
*/
int efx_tx_map_data(struct efx_tx_queue *tx_queue, struct sk_buff *skb,
unsigned int segment_count)
{
struct efx_nic *efx = tx_queue->efx;
struct device *dma_dev = &efx->pci_dev->dev;
unsigned int frag_index, nr_frags;
dma_addr_t dma_addr, unmap_addr;
unsigned short dma_flags;
size_t len, unmap_len;

nr_frags = skb_shinfo(skb)->nr_frags;
frag_index = 0;

/* Map header data. */
len = skb_headlen(skb);
dma_addr = dma_map_single(dma_dev, skb->data, len, DMA_TO_DEVICE);
dma_flags = EFX_TX_BUF_MAP_SINGLE;
unmap_len = len;
unmap_addr = dma_addr;

if (unlikely(dma_mapping_error(dma_dev, dma_addr)))
return -EIO;

if (segment_count) {
/* For TSO we need to put the header in to a separate
* descriptor. Map this separately if necessary.
*/
size_t header_len = skb_transport_header(skb) - skb->data +
(tcp_hdr(skb)->doff << 2u);

if (header_len != len) {
tx_queue->tso_long_headers++;
efx_tx_map_chunk(tx_queue, dma_addr, header_len);
len -= header_len;
dma_addr += header_len;
}
}

/* Add descriptors for each fragment. */
do {
struct efx_tx_buffer *buffer;
skb_frag_t *fragment;

buffer = efx_tx_map_chunk(tx_queue, dma_addr, len);

/* The final descriptor for a fragment is responsible for
* unmapping the whole fragment.
*/
buffer->flags = EFX_TX_BUF_CONT | dma_flags;
buffer->unmap_len = unmap_len;
buffer->dma_offset = buffer->dma_addr - unmap_addr;

if (frag_index >= nr_frags) {
/* Store SKB details with the final buffer for
* the completion.
*/
buffer->skb = skb;
buffer->flags = EFX_TX_BUF_SKB | dma_flags;
return 0;
}

/* Move on to the next fragment. */
fragment = &skb_shinfo(skb)->frags[frag_index++];
len = skb_frag_size(fragment);
dma_addr = skb_frag_dma_map(dma_dev, fragment,
0, len, DMA_TO_DEVICE);
dma_flags = 0;
unmap_len = len;
unmap_addr = dma_addr;

if (unlikely(dma_mapping_error(dma_dev, dma_addr)))
return -EIO;
} while (1);
}

/* Remove buffers put into a tx_queue for the current packet.
* None of the buffers must have an skb attached.
*/
Expand Down Expand Up @@ -877,131 +710,3 @@ void efx_xmit_done(struct efx_tx_queue *tx_queue, unsigned int index)
}
}
}

static unsigned int efx_tx_cb_page_count(struct efx_tx_queue *tx_queue)
{
return DIV_ROUND_UP(tx_queue->ptr_mask + 1, PAGE_SIZE >> EFX_TX_CB_ORDER);
}

int efx_probe_tx_queue(struct efx_tx_queue *tx_queue)
{
struct efx_nic *efx = tx_queue->efx;
unsigned int entries;
int rc;

/* Create the smallest power-of-two aligned ring */
entries = max(roundup_pow_of_two(efx->txq_entries), EFX_MIN_DMAQ_SIZE);
EFX_WARN_ON_PARANOID(entries > EFX_MAX_DMAQ_SIZE);
tx_queue->ptr_mask = entries - 1;

netif_dbg(efx, probe, efx->net_dev,
"creating TX queue %d size %#x mask %#x\n",
tx_queue->queue, efx->txq_entries, tx_queue->ptr_mask);

/* Allocate software ring */
tx_queue->buffer = kcalloc(entries, sizeof(*tx_queue->buffer),
GFP_KERNEL);
if (!tx_queue->buffer)
return -ENOMEM;

tx_queue->cb_page = kcalloc(efx_tx_cb_page_count(tx_queue),
sizeof(tx_queue->cb_page[0]), GFP_KERNEL);
if (!tx_queue->cb_page) {
rc = -ENOMEM;
goto fail1;
}

/* Allocate hardware ring */
rc = efx_nic_probe_tx(tx_queue);
if (rc)
goto fail2;

return 0;

fail2:
kfree(tx_queue->cb_page);
tx_queue->cb_page = NULL;
fail1:
kfree(tx_queue->buffer);
tx_queue->buffer = NULL;
return rc;
}

void efx_init_tx_queue(struct efx_tx_queue *tx_queue)
{
struct efx_nic *efx = tx_queue->efx;

netif_dbg(efx, drv, efx->net_dev,
"initialising TX queue %d\n", tx_queue->queue);

tx_queue->insert_count = 0;
tx_queue->write_count = 0;
tx_queue->packet_write_count = 0;
tx_queue->old_write_count = 0;
tx_queue->read_count = 0;
tx_queue->old_read_count = 0;
tx_queue->empty_read_count = 0 | EFX_EMPTY_COUNT_VALID;
tx_queue->xmit_more_available = false;
tx_queue->timestamping = (efx_ptp_use_mac_tx_timestamps(efx) &&
tx_queue->channel == efx_ptp_channel(efx));
tx_queue->completed_desc_ptr = tx_queue->ptr_mask;
tx_queue->completed_timestamp_major = 0;
tx_queue->completed_timestamp_minor = 0;

tx_queue->xdp_tx = efx_channel_is_xdp_tx(tx_queue->channel);

/* Set up default function pointers. These may get replaced by
* efx_nic_init_tx() based off NIC/queue capabilities.
*/
tx_queue->handle_tso = efx_enqueue_skb_tso;

/* Set up TX descriptor ring */
efx_nic_init_tx(tx_queue);

tx_queue->initialised = true;
}

void efx_fini_tx_queue(struct efx_tx_queue *tx_queue)
{
struct efx_tx_buffer *buffer;

netif_dbg(tx_queue->efx, drv, tx_queue->efx->net_dev,
"shutting down TX queue %d\n", tx_queue->queue);

if (!tx_queue->buffer)
return;

/* Free any buffers left in the ring */
while (tx_queue->read_count != tx_queue->write_count) {
unsigned int pkts_compl = 0, bytes_compl = 0;
buffer = &tx_queue->buffer[tx_queue->read_count & tx_queue->ptr_mask];
efx_dequeue_buffer(tx_queue, buffer, &pkts_compl, &bytes_compl);

++tx_queue->read_count;
}
tx_queue->xmit_more_available = false;
netdev_tx_reset_queue(tx_queue->core_txq);
}

void efx_remove_tx_queue(struct efx_tx_queue *tx_queue)
{
int i;

if (!tx_queue->buffer)
return;

netif_dbg(tx_queue->efx, drv, tx_queue->efx->net_dev,
"destroying TX queue %d\n", tx_queue->queue);
efx_nic_remove_tx(tx_queue);

if (tx_queue->cb_page) {
for (i = 0; i < efx_tx_cb_page_count(tx_queue); i++)
efx_nic_free_buffer(tx_queue->efx,
&tx_queue->cb_page[i]);
kfree(tx_queue->cb_page);
tx_queue->cb_page = NULL;
}

kfree(tx_queue->buffer);
tx_queue->buffer = NULL;
}
Loading

0 comments on commit 17d3b21

Please sign in to comment.