kernel-fxtec-pro1x/drivers/net/ethernet/sfc/rx.c
Ben Hutchings 9f2cb71c2b sfc: Leave interrupts and event queues enabled whenever we can
When SR-IOV is enabled we may receive FLR (Function-Level Reset)
events, associated queue flush events and requests from VF drivers at
any time.  Therefore we need to keep event queues and interrupts
enabled whenever possible.

Currently we stop interrupt-driven event processing before flushing RX
and TX queues; efx_nic_flush_queues() then polls event queues for
flush events and discards any others it finds.  Change it to work with
the regular event handling functions.

Currently efx_start_channel() fills RX queues synchronously when a
device is brought up.  This could now race with NAPI, so change it to
send fill events.

This was almost entirely written by Steve Hodgson, formerly
shodgson@solarflare.com.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
2012-02-16 00:24:46 +00:00

753 lines
22 KiB
C

/****************************************************************************
* Driver for Solarflare Solarstorm network controllers and boards
* Copyright 2005-2006 Fen Systems Ltd.
* Copyright 2005-2011 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/socket.h>
#include <linux/in.h>
#include <linux/slab.h>
#include <linux/ip.h>
#include <linux/tcp.h>
#include <linux/udp.h>
#include <linux/prefetch.h>
#include <linux/moduleparam.h>
#include <net/ip.h>
#include <net/checksum.h>
#include "net_driver.h"
#include "efx.h"
#include "nic.h"
#include "selftest.h"
#include "workarounds.h"
/* Number of RX descriptors pushed at once. */
#define EFX_RX_BATCH 8
/* Maximum size of a buffer sharing a page */
#define EFX_RX_HALF_PAGE ((PAGE_SIZE >> 1) - sizeof(struct efx_rx_page_state))
/* Size of buffer allocated for skb header area. */
#define EFX_SKB_HEADERS 64u
/*
* rx_alloc_method - RX buffer allocation method
*
* This driver supports two methods for allocating and using RX buffers:
* each RX buffer may be backed by an skb or by an order-n page.
*
* When GRO is in use then the second method has a lower overhead,
* since we don't have to allocate then free skbs on reassembled frames.
*
* Values:
* - RX_ALLOC_METHOD_AUTO = 0
* - RX_ALLOC_METHOD_SKB = 1
* - RX_ALLOC_METHOD_PAGE = 2
*
* The heuristic for %RX_ALLOC_METHOD_AUTO is a simple hysteresis count
* controlled by the parameters below.
*
* - Since pushing and popping descriptors are separated by the rx_queue
* size, so the watermarks should be ~rxd_size.
* - The performance win by using page-based allocation for GRO is less
* than the performance hit of using page-based allocation of non-GRO,
* so the watermarks should reflect this.
*
* Per channel we maintain a single variable, updated by each channel:
*
* rx_alloc_level += (gro_performed ? RX_ALLOC_FACTOR_GRO :
* RX_ALLOC_FACTOR_SKB)
* Per NAPI poll interval, we constrain rx_alloc_level to 0..MAX (which
* limits the hysteresis), and update the allocation strategy:
*
* rx_alloc_method = (rx_alloc_level > RX_ALLOC_LEVEL_GRO ?
* RX_ALLOC_METHOD_PAGE : RX_ALLOC_METHOD_SKB)
*/
static int rx_alloc_method = RX_ALLOC_METHOD_AUTO;
#define RX_ALLOC_LEVEL_GRO 0x2000
#define RX_ALLOC_LEVEL_MAX 0x3000
#define RX_ALLOC_FACTOR_GRO 1
#define RX_ALLOC_FACTOR_SKB (-2)
/* This is the percentage fill level below which new RX descriptors
* will be added to the RX descriptor ring.
*/
static unsigned int rx_refill_threshold = 90;
/* This is the percentage fill level to which an RX queue will be refilled
* when the "RX refill threshold" is reached.
*/
static unsigned int rx_refill_limit = 95;
/*
* RX maximum head room required.
*
* This must be at least 1 to prevent overflow and at least 2 to allow
* pipelined receives.
*/
#define EFX_RXD_HEAD_ROOM 2
/* Offset of ethernet header within page */
static inline unsigned int efx_rx_buf_offset(struct efx_nic *efx,
struct efx_rx_buffer *buf)
{
/* Offset is always within one page, so we don't need to consider
* the page order.
*/
return ((unsigned int) buf->dma_addr & (PAGE_SIZE - 1)) +
efx->type->rx_buffer_hash_size;
}
static inline unsigned int efx_rx_buf_size(struct efx_nic *efx)
{
return PAGE_SIZE << efx->rx_buffer_order;
}
static u8 *efx_rx_buf_eh(struct efx_nic *efx, struct efx_rx_buffer *buf)
{
if (buf->flags & EFX_RX_BUF_PAGE)
return page_address(buf->u.page) + efx_rx_buf_offset(efx, buf);
else
return (u8 *)buf->u.skb->data + efx->type->rx_buffer_hash_size;
}
static inline u32 efx_rx_buf_hash(const u8 *eh)
{
/* The ethernet header is always directly after any hash. */
#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) || NET_IP_ALIGN % 4 == 0
return __le32_to_cpup((const __le32 *)(eh - 4));
#else
const u8 *data = eh - 4;
return (u32)data[0] |
(u32)data[1] << 8 |
(u32)data[2] << 16 |
(u32)data[3] << 24;
#endif
}
/**
* efx_init_rx_buffers_skb - create EFX_RX_BATCH skb-based RX buffers
*
* @rx_queue: Efx RX queue
*
* This allocates EFX_RX_BATCH skbs, maps them for DMA, and populates a
* struct efx_rx_buffer for each one. Return a negative error code or 0
* on success. May fail having only inserted fewer than EFX_RX_BATCH
* buffers.
*/
static int efx_init_rx_buffers_skb(struct efx_rx_queue *rx_queue)
{
struct efx_nic *efx = rx_queue->efx;
struct net_device *net_dev = efx->net_dev;
struct efx_rx_buffer *rx_buf;
struct sk_buff *skb;
int skb_len = efx->rx_buffer_len;
unsigned index, count;
for (count = 0; count < EFX_RX_BATCH; ++count) {
index = rx_queue->added_count & rx_queue->ptr_mask;
rx_buf = efx_rx_buffer(rx_queue, index);
rx_buf->u.skb = skb = netdev_alloc_skb(net_dev, skb_len);
if (unlikely(!skb))
return -ENOMEM;
/* Adjust the SKB for padding and checksum */
skb_reserve(skb, NET_IP_ALIGN);
rx_buf->len = skb_len - NET_IP_ALIGN;
rx_buf->flags = 0;
skb->ip_summed = CHECKSUM_UNNECESSARY;
rx_buf->dma_addr = pci_map_single(efx->pci_dev,
skb->data, rx_buf->len,
PCI_DMA_FROMDEVICE);
if (unlikely(pci_dma_mapping_error(efx->pci_dev,
rx_buf->dma_addr))) {
dev_kfree_skb_any(skb);
rx_buf->u.skb = NULL;
return -EIO;
}
++rx_queue->added_count;
++rx_queue->alloc_skb_count;
}
return 0;
}
/**
* efx_init_rx_buffers_page - create EFX_RX_BATCH page-based RX buffers
*
* @rx_queue: Efx RX queue
*
* This allocates memory for EFX_RX_BATCH receive buffers, maps them for DMA,
* and populates struct efx_rx_buffers for each one. Return a negative error
* code or 0 on success. If a single page can be split between two buffers,
* then the page will either be inserted fully, or not at at all.
*/
static int efx_init_rx_buffers_page(struct efx_rx_queue *rx_queue)
{
struct efx_nic *efx = rx_queue->efx;
struct efx_rx_buffer *rx_buf;
struct page *page;
void *page_addr;
struct efx_rx_page_state *state;
dma_addr_t dma_addr;
unsigned index, count;
/* We can split a page between two buffers */
BUILD_BUG_ON(EFX_RX_BATCH & 1);
for (count = 0; count < EFX_RX_BATCH; ++count) {
page = alloc_pages(__GFP_COLD | __GFP_COMP | GFP_ATOMIC,
efx->rx_buffer_order);
if (unlikely(page == NULL))
return -ENOMEM;
dma_addr = pci_map_page(efx->pci_dev, page, 0,
efx_rx_buf_size(efx),
PCI_DMA_FROMDEVICE);
if (unlikely(pci_dma_mapping_error(efx->pci_dev, dma_addr))) {
__free_pages(page, efx->rx_buffer_order);
return -EIO;
}
page_addr = page_address(page);
state = page_addr;
state->refcnt = 0;
state->dma_addr = dma_addr;
page_addr += sizeof(struct efx_rx_page_state);
dma_addr += sizeof(struct efx_rx_page_state);
split:
index = rx_queue->added_count & rx_queue->ptr_mask;
rx_buf = efx_rx_buffer(rx_queue, index);
rx_buf->dma_addr = dma_addr + EFX_PAGE_IP_ALIGN;
rx_buf->u.page = page;
rx_buf->len = efx->rx_buffer_len - EFX_PAGE_IP_ALIGN;
rx_buf->flags = EFX_RX_BUF_PAGE;
++rx_queue->added_count;
++rx_queue->alloc_page_count;
++state->refcnt;
if ((~count & 1) && (efx->rx_buffer_len <= EFX_RX_HALF_PAGE)) {
/* Use the second half of the page */
get_page(page);
dma_addr += (PAGE_SIZE >> 1);
page_addr += (PAGE_SIZE >> 1);
++count;
goto split;
}
}
return 0;
}
static void efx_unmap_rx_buffer(struct efx_nic *efx,
struct efx_rx_buffer *rx_buf)
{
if ((rx_buf->flags & EFX_RX_BUF_PAGE) && rx_buf->u.page) {
struct efx_rx_page_state *state;
state = page_address(rx_buf->u.page);
if (--state->refcnt == 0) {
pci_unmap_page(efx->pci_dev,
state->dma_addr,
efx_rx_buf_size(efx),
PCI_DMA_FROMDEVICE);
}
} else if (!(rx_buf->flags & EFX_RX_BUF_PAGE) && rx_buf->u.skb) {
pci_unmap_single(efx->pci_dev, rx_buf->dma_addr,
rx_buf->len, PCI_DMA_FROMDEVICE);
}
}
static void efx_free_rx_buffer(struct efx_nic *efx,
struct efx_rx_buffer *rx_buf)
{
if ((rx_buf->flags & EFX_RX_BUF_PAGE) && rx_buf->u.page) {
__free_pages(rx_buf->u.page, efx->rx_buffer_order);
rx_buf->u.page = NULL;
} else if (!(rx_buf->flags & EFX_RX_BUF_PAGE) && rx_buf->u.skb) {
dev_kfree_skb_any(rx_buf->u.skb);
rx_buf->u.skb = NULL;
}
}
static void efx_fini_rx_buffer(struct efx_rx_queue *rx_queue,
struct efx_rx_buffer *rx_buf)
{
efx_unmap_rx_buffer(rx_queue->efx, rx_buf);
efx_free_rx_buffer(rx_queue->efx, rx_buf);
}
/* Attempt to resurrect the other receive buffer that used to share this page,
* which had previously been passed up to the kernel and freed. */
static void efx_resurrect_rx_buffer(struct efx_rx_queue *rx_queue,
struct efx_rx_buffer *rx_buf)
{
struct efx_rx_page_state *state = page_address(rx_buf->u.page);
struct efx_rx_buffer *new_buf;
unsigned fill_level, index;
/* +1 because efx_rx_packet() incremented removed_count. +1 because
* we'd like to insert an additional descriptor whilst leaving
* EFX_RXD_HEAD_ROOM for the non-recycle path */
fill_level = (rx_queue->added_count - rx_queue->removed_count + 2);
if (unlikely(fill_level > rx_queue->max_fill)) {
/* We could place "state" on a list, and drain the list in
* efx_fast_push_rx_descriptors(). For now, this will do. */
return;
}
++state->refcnt;
get_page(rx_buf->u.page);
index = rx_queue->added_count & rx_queue->ptr_mask;
new_buf = efx_rx_buffer(rx_queue, index);
new_buf->dma_addr = rx_buf->dma_addr ^ (PAGE_SIZE >> 1);
new_buf->u.page = rx_buf->u.page;
new_buf->len = rx_buf->len;
new_buf->flags = EFX_RX_BUF_PAGE;
++rx_queue->added_count;
}
/* Recycle the given rx buffer directly back into the rx_queue. There is
* always room to add this buffer, because we've just popped a buffer. */
static void efx_recycle_rx_buffer(struct efx_channel *channel,
struct efx_rx_buffer *rx_buf)
{
struct efx_nic *efx = channel->efx;
struct efx_rx_queue *rx_queue = efx_channel_get_rx_queue(channel);
struct efx_rx_buffer *new_buf;
unsigned index;
rx_buf->flags &= EFX_RX_BUF_PAGE;
if ((rx_buf->flags & EFX_RX_BUF_PAGE) &&
efx->rx_buffer_len <= EFX_RX_HALF_PAGE &&
page_count(rx_buf->u.page) == 1)
efx_resurrect_rx_buffer(rx_queue, rx_buf);
index = rx_queue->added_count & rx_queue->ptr_mask;
new_buf = efx_rx_buffer(rx_queue, index);
memcpy(new_buf, rx_buf, sizeof(*new_buf));
rx_buf->u.page = NULL;
++rx_queue->added_count;
}
/**
* efx_fast_push_rx_descriptors - push new RX descriptors quickly
* @rx_queue: RX descriptor queue
* This will aim to fill the RX descriptor queue up to
* @rx_queue->@fast_fill_limit. If there is insufficient atomic
* memory to do so, a slow fill will be scheduled.
*
* The caller must provide serialisation (none is used here). In practise,
* this means this function must run from the NAPI handler, or be called
* when NAPI is disabled.
*/
void efx_fast_push_rx_descriptors(struct efx_rx_queue *rx_queue)
{
struct efx_channel *channel = efx_rx_queue_channel(rx_queue);
unsigned fill_level;
int space, rc = 0;
/* Calculate current fill level, and exit if we don't need to fill */
fill_level = (rx_queue->added_count - rx_queue->removed_count);
EFX_BUG_ON_PARANOID(fill_level > rx_queue->efx->rxq_entries);
if (fill_level >= rx_queue->fast_fill_trigger)
goto out;
/* Record minimum fill level */
if (unlikely(fill_level < rx_queue->min_fill)) {
if (fill_level)
rx_queue->min_fill = fill_level;
}
space = rx_queue->fast_fill_limit - fill_level;
if (space < EFX_RX_BATCH)
goto out;
netif_vdbg(rx_queue->efx, rx_status, rx_queue->efx->net_dev,
"RX queue %d fast-filling descriptor ring from"
" level %d to level %d using %s allocation\n",
efx_rx_queue_index(rx_queue), fill_level,
rx_queue->fast_fill_limit,
channel->rx_alloc_push_pages ? "page" : "skb");
do {
if (channel->rx_alloc_push_pages)
rc = efx_init_rx_buffers_page(rx_queue);
else
rc = efx_init_rx_buffers_skb(rx_queue);
if (unlikely(rc)) {
/* Ensure that we don't leave the rx queue empty */
if (rx_queue->added_count == rx_queue->removed_count)
efx_schedule_slow_fill(rx_queue);
goto out;
}
} while ((space -= EFX_RX_BATCH) >= EFX_RX_BATCH);
netif_vdbg(rx_queue->efx, rx_status, rx_queue->efx->net_dev,
"RX queue %d fast-filled descriptor ring "
"to level %d\n", efx_rx_queue_index(rx_queue),
rx_queue->added_count - rx_queue->removed_count);
out:
if (rx_queue->notified_count != rx_queue->added_count)
efx_nic_notify_rx_desc(rx_queue);
}
void efx_rx_slow_fill(unsigned long context)
{
struct efx_rx_queue *rx_queue = (struct efx_rx_queue *)context;
/* Post an event to cause NAPI to run and refill the queue */
efx_nic_generate_fill_event(rx_queue);
++rx_queue->slow_fill_count;
}
static void efx_rx_packet__check_len(struct efx_rx_queue *rx_queue,
struct efx_rx_buffer *rx_buf,
int len, bool *leak_packet)
{
struct efx_nic *efx = rx_queue->efx;
unsigned max_len = rx_buf->len - efx->type->rx_buffer_padding;
if (likely(len <= max_len))
return;
/* The packet must be discarded, but this is only a fatal error
* if the caller indicated it was
*/
rx_buf->flags |= EFX_RX_PKT_DISCARD;
if ((len > rx_buf->len) && EFX_WORKAROUND_8071(efx)) {
if (net_ratelimit())
netif_err(efx, rx_err, efx->net_dev,
" RX queue %d seriously overlength "
"RX event (0x%x > 0x%x+0x%x). Leaking\n",
efx_rx_queue_index(rx_queue), len, max_len,
efx->type->rx_buffer_padding);
/* If this buffer was skb-allocated, then the meta
* data at the end of the skb will be trashed. So
* we have no choice but to leak the fragment.
*/
*leak_packet = !(rx_buf->flags & EFX_RX_BUF_PAGE);
efx_schedule_reset(efx, RESET_TYPE_RX_RECOVERY);
} else {
if (net_ratelimit())
netif_err(efx, rx_err, efx->net_dev,
" RX queue %d overlength RX event "
"(0x%x > 0x%x)\n",
efx_rx_queue_index(rx_queue), len, max_len);
}
efx_rx_queue_channel(rx_queue)->n_rx_overlength++;
}
/* Pass a received packet up through the generic GRO stack
*
* Handles driverlink veto, and passes the fragment up via
* the appropriate GRO method
*/
static void efx_rx_packet_gro(struct efx_channel *channel,
struct efx_rx_buffer *rx_buf,
const u8 *eh)
{
struct napi_struct *napi = &channel->napi_str;
gro_result_t gro_result;
/* Pass the skb/page into the GRO engine */
if (rx_buf->flags & EFX_RX_BUF_PAGE) {
struct efx_nic *efx = channel->efx;
struct page *page = rx_buf->u.page;
struct sk_buff *skb;
rx_buf->u.page = NULL;
skb = napi_get_frags(napi);
if (!skb) {
put_page(page);
return;
}
if (efx->net_dev->features & NETIF_F_RXHASH)
skb->rxhash = efx_rx_buf_hash(eh);
skb_fill_page_desc(skb, 0, page,
efx_rx_buf_offset(efx, rx_buf), rx_buf->len);
skb->len = rx_buf->len;
skb->data_len = rx_buf->len;
skb->truesize += rx_buf->len;
skb->ip_summed = ((rx_buf->flags & EFX_RX_PKT_CSUMMED) ?
CHECKSUM_UNNECESSARY : CHECKSUM_NONE);
skb_record_rx_queue(skb, channel->channel);
gro_result = napi_gro_frags(napi);
} else {
struct sk_buff *skb = rx_buf->u.skb;
EFX_BUG_ON_PARANOID(!(rx_buf->flags & EFX_RX_PKT_CSUMMED));
rx_buf->u.skb = NULL;
gro_result = napi_gro_receive(napi, skb);
}
if (gro_result == GRO_NORMAL) {
channel->rx_alloc_level += RX_ALLOC_FACTOR_SKB;
} else if (gro_result != GRO_DROP) {
channel->rx_alloc_level += RX_ALLOC_FACTOR_GRO;
channel->irq_mod_score += 2;
}
}
void efx_rx_packet(struct efx_rx_queue *rx_queue, unsigned int index,
unsigned int len, u16 flags)
{
struct efx_nic *efx = rx_queue->efx;
struct efx_channel *channel = efx_rx_queue_channel(rx_queue);
struct efx_rx_buffer *rx_buf;
bool leak_packet = false;
rx_buf = efx_rx_buffer(rx_queue, index);
rx_buf->flags |= flags;
/* This allows the refill path to post another buffer.
* EFX_RXD_HEAD_ROOM ensures that the slot we are using
* isn't overwritten yet.
*/
rx_queue->removed_count++;
/* Validate the length encoded in the event vs the descriptor pushed */
efx_rx_packet__check_len(rx_queue, rx_buf, len, &leak_packet);
netif_vdbg(efx, rx_status, efx->net_dev,
"RX queue %d received id %x at %llx+%x %s%s\n",
efx_rx_queue_index(rx_queue), index,
(unsigned long long)rx_buf->dma_addr, len,
(rx_buf->flags & EFX_RX_PKT_CSUMMED) ? " [SUMMED]" : "",
(rx_buf->flags & EFX_RX_PKT_DISCARD) ? " [DISCARD]" : "");
/* Discard packet, if instructed to do so */
if (unlikely(rx_buf->flags & EFX_RX_PKT_DISCARD)) {
if (unlikely(leak_packet))
channel->n_skbuff_leaks++;
else
efx_recycle_rx_buffer(channel, rx_buf);
/* Don't hold off the previous receive */
rx_buf = NULL;
goto out;
}
/* Release card resources - assumes all RX buffers consumed in-order
* per RX queue
*/
efx_unmap_rx_buffer(efx, rx_buf);
/* Prefetch nice and early so data will (hopefully) be in cache by
* the time we look at it.
*/
prefetch(efx_rx_buf_eh(efx, rx_buf));
/* Pipeline receives so that we give time for packet headers to be
* prefetched into cache.
*/
rx_buf->len = len - efx->type->rx_buffer_hash_size;
out:
if (channel->rx_pkt)
__efx_rx_packet(channel, channel->rx_pkt);
channel->rx_pkt = rx_buf;
}
static void efx_rx_deliver(struct efx_channel *channel,
struct efx_rx_buffer *rx_buf)
{
struct sk_buff *skb;
/* We now own the SKB */
skb = rx_buf->u.skb;
rx_buf->u.skb = NULL;
/* Set the SKB flags */
skb_checksum_none_assert(skb);
/* Pass the packet up */
netif_receive_skb(skb);
/* Update allocation strategy method */
channel->rx_alloc_level += RX_ALLOC_FACTOR_SKB;
}
/* Handle a received packet. Second half: Touches packet payload. */
void __efx_rx_packet(struct efx_channel *channel, struct efx_rx_buffer *rx_buf)
{
struct efx_nic *efx = channel->efx;
u8 *eh = efx_rx_buf_eh(efx, rx_buf);
/* If we're in loopback test, then pass the packet directly to the
* loopback layer, and free the rx_buf here
*/
if (unlikely(efx->loopback_selftest)) {
efx_loopback_rx_packet(efx, eh, rx_buf->len);
efx_free_rx_buffer(efx, rx_buf);
return;
}
if (!(rx_buf->flags & EFX_RX_BUF_PAGE)) {
struct sk_buff *skb = rx_buf->u.skb;
prefetch(skb_shinfo(skb));
skb_reserve(skb, efx->type->rx_buffer_hash_size);
skb_put(skb, rx_buf->len);
if (efx->net_dev->features & NETIF_F_RXHASH)
skb->rxhash = efx_rx_buf_hash(eh);
/* Move past the ethernet header. rx_buf->data still points
* at the ethernet header */
skb->protocol = eth_type_trans(skb, efx->net_dev);
skb_record_rx_queue(skb, channel->channel);
}
if (unlikely(!(efx->net_dev->features & NETIF_F_RXCSUM)))
rx_buf->flags &= ~EFX_RX_PKT_CSUMMED;
if (likely(rx_buf->flags & (EFX_RX_BUF_PAGE | EFX_RX_PKT_CSUMMED)))
efx_rx_packet_gro(channel, rx_buf, eh);
else
efx_rx_deliver(channel, rx_buf);
}
void efx_rx_strategy(struct efx_channel *channel)
{
enum efx_rx_alloc_method method = rx_alloc_method;
/* Only makes sense to use page based allocation if GRO is enabled */
if (!(channel->efx->net_dev->features & NETIF_F_GRO)) {
method = RX_ALLOC_METHOD_SKB;
} else if (method == RX_ALLOC_METHOD_AUTO) {
/* Constrain the rx_alloc_level */
if (channel->rx_alloc_level < 0)
channel->rx_alloc_level = 0;
else if (channel->rx_alloc_level > RX_ALLOC_LEVEL_MAX)
channel->rx_alloc_level = RX_ALLOC_LEVEL_MAX;
/* Decide on the allocation method */
method = ((channel->rx_alloc_level > RX_ALLOC_LEVEL_GRO) ?
RX_ALLOC_METHOD_PAGE : RX_ALLOC_METHOD_SKB);
}
/* Push the option */
channel->rx_alloc_push_pages = (method == RX_ALLOC_METHOD_PAGE);
}
int efx_probe_rx_queue(struct efx_rx_queue *rx_queue)
{
struct efx_nic *efx = rx_queue->efx;
unsigned int entries;
int rc;
/* Create the smallest power-of-two aligned ring */
entries = max(roundup_pow_of_two(efx->rxq_entries), EFX_MIN_DMAQ_SIZE);
EFX_BUG_ON_PARANOID(entries > EFX_MAX_DMAQ_SIZE);
rx_queue->ptr_mask = entries - 1;
netif_dbg(efx, probe, efx->net_dev,
"creating RX queue %d size %#x mask %#x\n",
efx_rx_queue_index(rx_queue), efx->rxq_entries,
rx_queue->ptr_mask);
/* Allocate RX buffers */
rx_queue->buffer = kcalloc(entries, sizeof(*rx_queue->buffer),
GFP_KERNEL);
if (!rx_queue->buffer)
return -ENOMEM;
rc = efx_nic_probe_rx(rx_queue);
if (rc) {
kfree(rx_queue->buffer);
rx_queue->buffer = NULL;
}
return rc;
}
void efx_init_rx_queue(struct efx_rx_queue *rx_queue)
{
struct efx_nic *efx = rx_queue->efx;
unsigned int max_fill, trigger, limit;
netif_dbg(rx_queue->efx, drv, rx_queue->efx->net_dev,
"initialising RX queue %d\n", efx_rx_queue_index(rx_queue));
/* Initialise ptr fields */
rx_queue->added_count = 0;
rx_queue->notified_count = 0;
rx_queue->removed_count = 0;
rx_queue->min_fill = -1U;
/* Initialise limit fields */
max_fill = efx->rxq_entries - EFX_RXD_HEAD_ROOM;
trigger = max_fill * min(rx_refill_threshold, 100U) / 100U;
limit = max_fill * min(rx_refill_limit, 100U) / 100U;
rx_queue->max_fill = max_fill;
rx_queue->fast_fill_trigger = trigger;
rx_queue->fast_fill_limit = limit;
/* Set up RX descriptor ring */
rx_queue->enabled = true;
efx_nic_init_rx(rx_queue);
}
void efx_fini_rx_queue(struct efx_rx_queue *rx_queue)
{
int i;
struct efx_rx_buffer *rx_buf;
netif_dbg(rx_queue->efx, drv, rx_queue->efx->net_dev,
"shutting down RX queue %d\n", efx_rx_queue_index(rx_queue));
/* A flush failure might have left rx_queue->enabled */
rx_queue->enabled = false;
del_timer_sync(&rx_queue->slow_fill);
efx_nic_fini_rx(rx_queue);
/* Release RX buffers NB start at index 0 not current HW ptr */
if (rx_queue->buffer) {
for (i = 0; i <= rx_queue->ptr_mask; i++) {
rx_buf = efx_rx_buffer(rx_queue, i);
efx_fini_rx_buffer(rx_queue, rx_buf);
}
}
}
void efx_remove_rx_queue(struct efx_rx_queue *rx_queue)
{
netif_dbg(rx_queue->efx, drv, rx_queue->efx->net_dev,
"destroying RX queue %d\n", efx_rx_queue_index(rx_queue));
efx_nic_remove_rx(rx_queue);
kfree(rx_queue->buffer);
rx_queue->buffer = NULL;
}
module_param(rx_alloc_method, int, 0644);
MODULE_PARM_DESC(rx_alloc_method, "Allocation method used for RX buffers");
module_param(rx_refill_threshold, uint, 0444);
MODULE_PARM_DESC(rx_refill_threshold,
"RX descriptor ring fast/slow fill threshold (%)");