Commit 08dcc47c authored by Lendacky, Thomas's avatar Lendacky, Thomas Committed by David S. Miller

amd-xgbe: Use page allocations for Rx buffers

Use page allocations for Rx buffers instead of pre-allocating skbs
of a set size.
Signed-off-by: default avatarTom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent aa96bd3c
......@@ -117,7 +117,7 @@
#include "xgbe.h"
#include "xgbe-common.h"
static void xgbe_unmap_skb(struct xgbe_prv_data *, struct xgbe_ring_data *);
static void xgbe_unmap_rdata(struct xgbe_prv_data *, struct xgbe_ring_data *);
static void xgbe_free_ring(struct xgbe_prv_data *pdata,
struct xgbe_ring *ring)
......@@ -131,13 +131,24 @@ static void xgbe_free_ring(struct xgbe_prv_data *pdata,
if (ring->rdata) {
for (i = 0; i < ring->rdesc_count; i++) {
rdata = XGBE_GET_DESC_DATA(ring, i);
xgbe_unmap_skb(pdata, rdata);
xgbe_unmap_rdata(pdata, rdata);
}
kfree(ring->rdata);
ring->rdata = NULL;
}
if (ring->rx_pa.pages) {
dma_unmap_page(pdata->dev, ring->rx_pa.pages_dma,
ring->rx_pa.pages_len, DMA_FROM_DEVICE);
put_page(ring->rx_pa.pages);
ring->rx_pa.pages = NULL;
ring->rx_pa.pages_len = 0;
ring->rx_pa.pages_offset = 0;
ring->rx_pa.pages_dma = 0;
}
if (ring->rdesc) {
dma_free_coherent(pdata->dev,
(sizeof(struct xgbe_ring_desc) *
......@@ -233,6 +244,65 @@ static int xgbe_alloc_ring_resources(struct xgbe_prv_data *pdata)
return ret;
}
static int xgbe_map_rx_buffer(struct xgbe_prv_data *pdata,
struct xgbe_ring *ring,
struct xgbe_ring_data *rdata)
{
if (!ring->rx_pa.pages) {
struct page *pages = NULL;
dma_addr_t pages_dma;
gfp_t gfp;
int order, ret;
/* Try to obtain pages, decreasing order if necessary */
gfp = GFP_ATOMIC | __GFP_COLD | __GFP_COMP;
order = max_t(int, PAGE_ALLOC_COSTLY_ORDER, 1);
while (--order >= 0) {
pages = alloc_pages(gfp, order);
if (pages)
break;
}
if (!pages)
return -ENOMEM;
/* Map the pages */
pages_dma = dma_map_page(pdata->dev, pages, 0,
PAGE_SIZE << order, DMA_FROM_DEVICE);
ret = dma_mapping_error(pdata->dev, pages_dma);
if (ret) {
put_page(pages);
return ret;
}
/* Set the values for this ring */
ring->rx_pa.pages = pages;
ring->rx_pa.pages_len = PAGE_SIZE << order;
ring->rx_pa.pages_offset = 0;
ring->rx_pa.pages_dma = pages_dma;
}
get_page(ring->rx_pa.pages);
rdata->rx_pa = ring->rx_pa;
rdata->rx_dma = ring->rx_pa.pages_dma + ring->rx_pa.pages_offset;
rdata->rx_dma_len = pdata->rx_buf_size;
ring->rx_pa.pages_offset += pdata->rx_buf_size;
if ((ring->rx_pa.pages_offset + pdata->rx_buf_size) >
ring->rx_pa.pages_len) {
/* This data descriptor is responsible for unmapping page(s) */
rdata->rx_unmap = ring->rx_pa;
/* Get a new allocation next time */
ring->rx_pa.pages = NULL;
ring->rx_pa.pages_len = 0;
ring->rx_pa.pages_offset = 0;
ring->rx_pa.pages_dma = 0;
}
return 0;
}
static void xgbe_wrapper_tx_descriptor_init(struct xgbe_prv_data *pdata)
{
struct xgbe_hw_if *hw_if = &pdata->hw_if;
......@@ -281,8 +351,7 @@ static void xgbe_wrapper_rx_descriptor_init(struct xgbe_prv_data *pdata)
struct xgbe_ring *ring;
struct xgbe_ring_desc *rdesc;
struct xgbe_ring_data *rdata;
dma_addr_t rdesc_dma, skb_dma;
struct sk_buff *skb = NULL;
dma_addr_t rdesc_dma;
unsigned int i, j;
DBGPR("-->xgbe_wrapper_rx_descriptor_init\n");
......@@ -302,22 +371,8 @@ static void xgbe_wrapper_rx_descriptor_init(struct xgbe_prv_data *pdata)
rdata->rdesc = rdesc;
rdata->rdesc_dma = rdesc_dma;
/* Allocate skb & assign to each rdesc */
skb = dev_alloc_skb(pdata->rx_buf_size);
if (skb == NULL)
break;
skb_dma = dma_map_single(pdata->dev, skb->data,
pdata->rx_buf_size,
DMA_FROM_DEVICE);
if (dma_mapping_error(pdata->dev, skb_dma)) {
netdev_alert(pdata->netdev,
"failed to do the dma map\n");
dev_kfree_skb_any(skb);
if (xgbe_map_rx_buffer(pdata, ring, rdata))
break;
}
rdata->skb = skb;
rdata->skb_dma = skb_dma;
rdata->skb_dma_len = pdata->rx_buf_size;
rdesc++;
rdesc_dma += sizeof(struct xgbe_ring_desc);
......@@ -334,7 +389,7 @@ static void xgbe_wrapper_rx_descriptor_init(struct xgbe_prv_data *pdata)
DBGPR("<--xgbe_wrapper_rx_descriptor_init\n");
}
static void xgbe_unmap_skb(struct xgbe_prv_data *pdata,
static void xgbe_unmap_rdata(struct xgbe_prv_data *pdata,
struct xgbe_ring_data *rdata)
{
if (rdata->skb_dma) {
......@@ -354,6 +409,21 @@ static void xgbe_unmap_skb(struct xgbe_prv_data *pdata,
rdata->skb = NULL;
}
if (rdata->rx_pa.pages)
put_page(rdata->rx_pa.pages);
if (rdata->rx_unmap.pages) {
dma_unmap_page(pdata->dev, rdata->rx_unmap.pages_dma,
rdata->rx_unmap.pages_len, DMA_FROM_DEVICE);
put_page(rdata->rx_unmap.pages);
}
memset(&rdata->rx_pa, 0, sizeof(rdata->rx_pa));
memset(&rdata->rx_unmap, 0, sizeof(rdata->rx_unmap));
rdata->rx_dma = 0;
rdata->rx_dma_len = 0;
rdata->tso_header = 0;
rdata->len = 0;
rdata->interrupt = 0;
......@@ -494,7 +564,7 @@ static int xgbe_map_tx_skb(struct xgbe_channel *channel, struct sk_buff *skb)
err_out:
while (start_index < cur_index) {
rdata = XGBE_GET_DESC_DATA(ring, start_index++);
xgbe_unmap_skb(pdata, rdata);
xgbe_unmap_rdata(pdata, rdata);
}
DBGPR("<--xgbe_map_tx_skb: count=0\n");
......@@ -502,40 +572,25 @@ static int xgbe_map_tx_skb(struct xgbe_channel *channel, struct sk_buff *skb)
return 0;
}
static void xgbe_realloc_skb(struct xgbe_channel *channel)
static void xgbe_realloc_rx_buffer(struct xgbe_channel *channel)
{
struct xgbe_prv_data *pdata = channel->pdata;
struct xgbe_hw_if *hw_if = &pdata->hw_if;
struct xgbe_ring *ring = channel->rx_ring;
struct xgbe_ring_data *rdata;
struct sk_buff *skb = NULL;
dma_addr_t skb_dma;
int i;
DBGPR("-->xgbe_realloc_skb: rx_ring->rx.realloc_index = %u\n",
DBGPR("-->xgbe_realloc_rx_buffer: rx_ring->rx.realloc_index = %u\n",
ring->rx.realloc_index);
for (i = 0; i < ring->dirty; i++) {
rdata = XGBE_GET_DESC_DATA(ring, ring->rx.realloc_index);
/* Reset rdata values */
xgbe_unmap_skb(pdata, rdata);
xgbe_unmap_rdata(pdata, rdata);
/* Allocate skb & assign to each rdesc */
skb = dev_alloc_skb(pdata->rx_buf_size);
if (skb == NULL)
if (xgbe_map_rx_buffer(pdata, ring, rdata))
break;
skb_dma = dma_map_single(pdata->dev, skb->data,
pdata->rx_buf_size, DMA_FROM_DEVICE);
if (dma_mapping_error(pdata->dev, skb_dma)) {
netdev_alert(pdata->netdev,
"failed to do the dma map\n");
dev_kfree_skb_any(skb);
break;
}
rdata->skb = skb;
rdata->skb_dma = skb_dma;
rdata->skb_dma_len = pdata->rx_buf_size;
hw_if->rx_desc_reset(rdata);
......@@ -543,7 +598,7 @@ static void xgbe_realloc_skb(struct xgbe_channel *channel)
}
ring->dirty = 0;
DBGPR("<--xgbe_realloc_skb\n");
DBGPR("<--xgbe_realloc_rx_buffer\n");
}
void xgbe_init_function_ptrs_desc(struct xgbe_desc_if *desc_if)
......@@ -553,8 +608,8 @@ void xgbe_init_function_ptrs_desc(struct xgbe_desc_if *desc_if)
desc_if->alloc_ring_resources = xgbe_alloc_ring_resources;
desc_if->free_ring_resources = xgbe_free_ring_resources;
desc_if->map_tx_skb = xgbe_map_tx_skb;
desc_if->realloc_skb = xgbe_realloc_skb;
desc_if->unmap_skb = xgbe_unmap_skb;
desc_if->realloc_rx_buffer = xgbe_realloc_rx_buffer;
desc_if->unmap_rdata = xgbe_unmap_rdata;
desc_if->wrapper_tx_desc_init = xgbe_wrapper_tx_descriptor_init;
desc_if->wrapper_rx_desc_init = xgbe_wrapper_rx_descriptor_init;
......
......@@ -880,13 +880,15 @@ static void xgbe_tx_desc_reset(struct xgbe_ring_data *rdata)
rdesc->desc1 = 0;
rdesc->desc2 = 0;
rdesc->desc3 = 0;
/* Make sure ownership is written to the descriptor */
wmb();
}
static void xgbe_tx_desc_init(struct xgbe_channel *channel)
{
struct xgbe_ring *ring = channel->tx_ring;
struct xgbe_ring_data *rdata;
struct xgbe_ring_desc *rdesc;
int i;
int start_index = ring->cur;
......@@ -895,26 +897,11 @@ static void xgbe_tx_desc_init(struct xgbe_channel *channel)
/* Initialze all descriptors */
for (i = 0; i < ring->rdesc_count; i++) {
rdata = XGBE_GET_DESC_DATA(ring, i);
rdesc = rdata->rdesc;
/* Initialize Tx descriptor
* Set buffer 1 (lo) address to zero
* Set buffer 1 (hi) address to zero
* Reset all other control bits (IC, TTSE, B2L & B1L)
* Reset all other control bits (OWN, CTXT, FD, LD, CPC, CIC,
* etc)
*/
rdesc->desc0 = 0;
rdesc->desc1 = 0;
rdesc->desc2 = 0;
rdesc->desc3 = 0;
/* Initialize Tx descriptor */
xgbe_tx_desc_reset(rdata);
}
/* Make sure everything is written to the descriptor(s) before
* telling the device about them
*/
wmb();
/* Update the total number of Tx descriptors */
XGMAC_DMA_IOWRITE(channel, DMA_CH_TDRLR, ring->rdesc_count - 1);
......@@ -939,8 +926,8 @@ static void xgbe_rx_desc_reset(struct xgbe_ring_data *rdata)
* Set buffer 2 (hi) address to zero and set control bits
* OWN and INTE
*/
rdesc->desc0 = cpu_to_le32(lower_32_bits(rdata->skb_dma));
rdesc->desc1 = cpu_to_le32(upper_32_bits(rdata->skb_dma));
rdesc->desc0 = cpu_to_le32(lower_32_bits(rdata->rx_dma));
rdesc->desc1 = cpu_to_le32(upper_32_bits(rdata->rx_dma));
rdesc->desc2 = 0;
rdesc->desc3 = 0;
......@@ -964,7 +951,6 @@ static void xgbe_rx_desc_init(struct xgbe_channel *channel)
struct xgbe_prv_data *pdata = channel->pdata;
struct xgbe_ring *ring = channel->rx_ring;
struct xgbe_ring_data *rdata;
struct xgbe_ring_desc *rdesc;
unsigned int start_index = ring->cur;
unsigned int rx_coalesce, rx_frames;
unsigned int i;
......@@ -977,34 +963,16 @@ static void xgbe_rx_desc_init(struct xgbe_channel *channel)
/* Initialize all descriptors */
for (i = 0; i < ring->rdesc_count; i++) {
rdata = XGBE_GET_DESC_DATA(ring, i);
rdesc = rdata->rdesc;
/* Initialize Rx descriptor
* Set buffer 1 (lo) address to dma address (lo)
* Set buffer 1 (hi) address to dma address (hi)
* Set buffer 2 (lo) address to zero
* Set buffer 2 (hi) address to zero and set control
* bits OWN and INTE appropriateley
*/
rdesc->desc0 = cpu_to_le32(lower_32_bits(rdata->skb_dma));
rdesc->desc1 = cpu_to_le32(upper_32_bits(rdata->skb_dma));
rdesc->desc2 = 0;
rdesc->desc3 = 0;
XGMAC_SET_BITS_LE(rdesc->desc3, RX_NORMAL_DESC3, OWN, 1);
XGMAC_SET_BITS_LE(rdesc->desc3, RX_NORMAL_DESC3, INTE, 1);
rdata->interrupt = 1;
if (rx_coalesce && (!rx_frames || ((i + 1) % rx_frames))) {
/* Clear interrupt on completion bit */
XGMAC_SET_BITS_LE(rdesc->desc3, RX_NORMAL_DESC3, INTE,
0);
/* Set interrupt on completion bit as appropriate */
if (rx_coalesce && (!rx_frames || ((i + 1) % rx_frames)))
rdata->interrupt = 0;
}
}
else
rdata->interrupt = 1;
/* Make sure everything is written to the descriptors before
* telling the device about them
*/
wmb();
/* Initialize Rx descriptor */
xgbe_rx_desc_reset(rdata);
}
/* Update the total number of Rx descriptors */
XGMAC_DMA_IOWRITE(channel, DMA_CH_RDRLR, ring->rdesc_count - 1);
......
......@@ -218,8 +218,8 @@ static int xgbe_calc_rx_buf_size(struct net_device *netdev, unsigned int mtu)
}
rx_buf_size = mtu + ETH_HLEN + ETH_FCS_LEN + VLAN_HLEN;
if (rx_buf_size < XGBE_RX_MIN_BUF_SIZE)
rx_buf_size = XGBE_RX_MIN_BUF_SIZE;
rx_buf_size = clamp_val(rx_buf_size, XGBE_RX_MIN_BUF_SIZE, PAGE_SIZE);
rx_buf_size = (rx_buf_size + XGBE_RX_BUF_ALIGN - 1) &
~(XGBE_RX_BUF_ALIGN - 1);
......@@ -546,7 +546,7 @@ void xgbe_init_rx_coalesce(struct xgbe_prv_data *pdata)
DBGPR("<--xgbe_init_rx_coalesce\n");
}
static void xgbe_free_tx_skbuff(struct xgbe_prv_data *pdata)
static void xgbe_free_tx_data(struct xgbe_prv_data *pdata)
{
struct xgbe_desc_if *desc_if = &pdata->desc_if;
struct xgbe_channel *channel;
......@@ -554,7 +554,7 @@ static void xgbe_free_tx_skbuff(struct xgbe_prv_data *pdata)
struct xgbe_ring_data *rdata;
unsigned int i, j;
DBGPR("-->xgbe_free_tx_skbuff\n");
DBGPR("-->xgbe_free_tx_data\n");
channel = pdata->channel;
for (i = 0; i < pdata->channel_count; i++, channel++) {
......@@ -564,14 +564,14 @@ static void xgbe_free_tx_skbuff(struct xgbe_prv_data *pdata)
for (j = 0; j < ring->rdesc_count; j++) {
rdata = XGBE_GET_DESC_DATA(ring, j);
desc_if->unmap_skb(pdata, rdata);
desc_if->unmap_rdata(pdata, rdata);
}
}
DBGPR("<--xgbe_free_tx_skbuff\n");
DBGPR("<--xgbe_free_tx_data\n");
}
static void xgbe_free_rx_skbuff(struct xgbe_prv_data *pdata)
static void xgbe_free_rx_data(struct xgbe_prv_data *pdata)
{
struct xgbe_desc_if *desc_if = &pdata->desc_if;
struct xgbe_channel *channel;
......@@ -579,7 +579,7 @@ static void xgbe_free_rx_skbuff(struct xgbe_prv_data *pdata)
struct xgbe_ring_data *rdata;
unsigned int i, j;
DBGPR("-->xgbe_free_rx_skbuff\n");
DBGPR("-->xgbe_free_rx_data\n");
channel = pdata->channel;
for (i = 0; i < pdata->channel_count; i++, channel++) {
......@@ -589,11 +589,11 @@ static void xgbe_free_rx_skbuff(struct xgbe_prv_data *pdata)
for (j = 0; j < ring->rdesc_count; j++) {
rdata = XGBE_GET_DESC_DATA(ring, j);
desc_if->unmap_skb(pdata, rdata);
desc_if->unmap_rdata(pdata, rdata);
}
}
DBGPR("<--xgbe_free_rx_skbuff\n");
DBGPR("<--xgbe_free_rx_data\n");
}
static void xgbe_adjust_link(struct net_device *netdev)
......@@ -839,8 +839,8 @@ static void xgbe_restart_dev(struct xgbe_prv_data *pdata, unsigned int reset)
xgbe_stop(pdata);
synchronize_irq(pdata->irq_number);
xgbe_free_tx_skbuff(pdata);
xgbe_free_rx_skbuff(pdata);
xgbe_free_tx_data(pdata);
xgbe_free_rx_data(pdata);
/* Issue software reset to device if requested */
if (reset)
......@@ -1609,7 +1609,7 @@ static void xgbe_rx_refresh(struct xgbe_channel *channel)
struct xgbe_ring *ring = channel->rx_ring;
struct xgbe_ring_data *rdata;
desc_if->realloc_skb(channel);
desc_if->realloc_rx_buffer(channel);
/* Update the Rx Tail Pointer Register with address of
* the last cleaned entry */
......@@ -1618,6 +1618,37 @@ static void xgbe_rx_refresh(struct xgbe_channel *channel)
lower_32_bits(rdata->rdesc_dma));
}
static struct sk_buff *xgbe_create_skb(struct xgbe_prv_data *pdata,
struct xgbe_ring_data *rdata,
unsigned int len)
{
struct net_device *netdev = pdata->netdev;
struct sk_buff *skb;
u8 *packet;
unsigned int copy_len;
skb = netdev_alloc_skb_ip_align(netdev, XGBE_SKB_ALLOC_SIZE);
if (!skb)
return NULL;
packet = page_address(rdata->rx_pa.pages) + rdata->rx_pa.pages_offset;
copy_len = min_t(unsigned int, XGBE_SKB_ALLOC_SIZE, len);
skb_copy_to_linear_data(skb, packet, copy_len);
skb_put(skb, copy_len);
rdata->rx_pa.pages_offset += copy_len;
len -= copy_len;
if (len)
skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags,
rdata->rx_pa.pages,
rdata->rx_pa.pages_offset,
len, rdata->rx_dma_len);
else
put_page(rdata->rx_pa.pages);
return skb;
}
static int xgbe_tx_poll(struct xgbe_channel *channel)
{
struct xgbe_prv_data *pdata = channel->pdata;
......@@ -1651,7 +1682,7 @@ static int xgbe_tx_poll(struct xgbe_channel *channel)
#endif
/* Free the SKB and reset the descriptor for re-use */
desc_if->unmap_skb(pdata, rdata);
desc_if->unmap_rdata(pdata, rdata);
hw_if->tx_desc_reset(rdata);
processed++;
......@@ -1726,9 +1757,9 @@ static int xgbe_rx_poll(struct xgbe_channel *channel, int budget)
ring->cur++;
ring->dirty++;
dma_unmap_single(pdata->dev, rdata->skb_dma,
rdata->skb_dma_len, DMA_FROM_DEVICE);
rdata->skb_dma = 0;
dma_sync_single_for_cpu(pdata->dev, rdata->rx_dma,
rdata->rx_dma_len,
DMA_FROM_DEVICE);
incomplete = XGMAC_GET_BITS(packet->attributes,
RX_PACKET_ATTRIBUTES,
......@@ -1753,26 +1784,22 @@ static int xgbe_rx_poll(struct xgbe_channel *channel, int budget)
if (!context) {
put_len = rdata->len - len;
if (skb) {
if (pskb_expand_head(skb, 0, put_len,
GFP_ATOMIC)) {
DBGPR("pskb_expand_head error\n");
if (incomplete) {
len += put_len;
if (!skb) {
skb = xgbe_create_skb(pdata, rdata, put_len);
if (!skb) {
error = 1;
goto read_again;
}
dev_kfree_skb(skb);
goto next_packet;
}
memcpy(skb_tail_pointer(skb), rdata->skb->data,
put_len);
} else {
skb = rdata->skb;
rdata->skb = NULL;
skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags,
rdata->rx_pa.pages,
rdata->rx_pa.pages_offset,
put_len, rdata->rx_dma_len);
}
skb_put(skb, put_len);
len += put_len;
rdata->rx_pa.pages = NULL;
}
if (incomplete || context_next)
......
......@@ -142,6 +142,7 @@
#define XGBE_RX_MIN_BUF_SIZE (ETH_FRAME_LEN + ETH_FCS_LEN + VLAN_HLEN)
#define XGBE_RX_BUF_ALIGN 64
#define XGBE_SKB_ALLOC_SIZE 256
#define XGBE_MAX_DMA_CHANNELS 16
#define XGBE_MAX_QUEUES 16
......@@ -240,6 +241,15 @@ struct xgbe_ring_desc {
u32 desc3;
};
/* Page allocation related values */
struct xgbe_page_alloc {
struct page *pages;
unsigned int pages_len;
unsigned int pages_offset;
dma_addr_t pages_dma;
};
/* Structure used to hold information related to the descriptor
* and the packet associated with the descriptor (always use
* use the XGBE_GET_DESC_DATA macro to access this data from the ring)
......@@ -253,6 +263,12 @@ struct xgbe_ring_data {
unsigned int skb_dma_len; /* Length of SKB DMA area */
unsigned int tso_header; /* TSO header indicator */
struct xgbe_page_alloc rx_pa; /* Rx buffer page allocation */
struct xgbe_page_alloc rx_unmap;
dma_addr_t rx_dma; /* DMA address of Rx buffer */
unsigned int rx_dma_len; /* Length of the Rx DMA buffer */
unsigned short len; /* Length of received Rx packet */
unsigned int interrupt; /* Interrupt indicator */
......@@ -291,6 +307,9 @@ struct xgbe_ring {
*/
struct xgbe_ring_data *rdata;
/* Page allocation for RX buffers */
struct xgbe_page_alloc rx_pa;
/* Ring index values
* cur - Tx: index of descriptor to be used for current transfer
* Rx: index of descriptor to check for packet availability
......@@ -515,8 +534,8 @@ struct xgbe_desc_if {
int (*alloc_ring_resources)(struct xgbe_prv_data *);
void (*free_ring_resources)(struct xgbe_prv_data *);
int (*map_tx_skb)(struct xgbe_channel *, struct sk_buff *);
void (*realloc_skb)(struct xgbe_channel *);
void (*unmap_skb)(struct xgbe_prv_data *, struct xgbe_ring_data *);
void (*realloc_rx_buffer)(struct xgbe_channel *);
void (*unmap_rdata)(struct xgbe_prv_data *, struct xgbe_ring_data *);
void (*wrapper_tx_desc_init)(struct xgbe_prv_data *);
void (*wrapper_rx_desc_init)(struct xgbe_prv_data *);
};
......@@ -624,7 +643,7 @@ struct xgbe_prv_data {
unsigned int rx_riwt;
unsigned int rx_frames;
/* Current MTU */
/* Current Rx buffer size */
unsigned int rx_buf_size;
/* Flow control settings */
......
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