@@ -68,6 +68,7 @@ struct gve_rx_data_queue {
dma_addr_t data_bus; /* dma mapping of the slots */
struct gve_rx_slot_page_info *page_info; /* page info of the buffers */
struct gve_queue_page_list *qpl; /* qpl assigned to this queue */
+ bool raw_addressing; /* use raw_addressing? */
};
struct gve_priv;
@@ -82,11 +83,14 @@ struct gve_rx_ring {
u32 cnt; /* free-running total number of completed packets */
u32 fill_cnt; /* free-running total number of descs and buffs posted */
u32 mask; /* masks the cnt and fill_cnt to the size of the ring */
+ u32 db_threshold; /* threshold for posting new buffs and descs */
u64 rx_copybreak_pkt; /* free-running count of copybreak packets */
u64 rx_copied_pkt; /* free-running total number of copied packets */
u64 rx_skb_alloc_fail; /* free-running count of skb alloc fails */
u64 rx_buf_alloc_fail; /* free-running count of buffer alloc fails */
u64 rx_desc_err_dropped_pkt; /* free-running count of packets dropped by descriptor error */
+ /* free-running count of packets dropped because of lack of buffer refill */
+ u64 rx_no_refill_dropped_pkt;
u32 q_num; /* queue index */
u32 ntfy_id; /* notification block index */
struct gve_queue_resources *q_resources; /* head and tail pointer idx */
@@ -194,7 +198,7 @@ struct gve_priv {
u16 tx_desc_cnt; /* num desc per ring */
u16 rx_desc_cnt; /* num desc per ring */
u16 tx_pages_per_qpl; /* tx buffer length */
- u16 rx_pages_per_qpl; /* rx buffer length */
+ u16 rx_data_slot_cnt; /* rx buffer length */
u64 max_registered_pages;
u64 num_registered_pages; /* num pages registered with NIC */
u32 rx_copybreak; /* copy packets smaller than this */
@@ -444,7 +448,10 @@ static inline u32 gve_num_tx_qpls(struct gve_priv *priv)
*/
static inline u32 gve_num_rx_qpls(struct gve_priv *priv)
{
- return priv->rx_cfg.num_queues;
+ if (priv->raw_addressing)
+ return 0;
+ else
+ return priv->rx_cfg.num_queues;
}
/* Returns a pointer to the next available tx qpl in the list of qpls
@@ -357,8 +357,10 @@ static int gve_adminq_create_rx_queue(struct gve_priv *priv, u32 queue_index)
{
struct gve_rx_ring *rx = &priv->rx[queue_index];
union gve_adminq_command cmd;
+ u32 qpl_id;
int err;
+ qpl_id = priv->raw_addressing ? GVE_RAW_ADDRESSING_QPL_ID : rx->data.qpl->id;
memset(&cmd, 0, sizeof(cmd));
cmd.opcode = cpu_to_be32(GVE_ADMINQ_CREATE_RX_QUEUE);
cmd.create_rx_queue = (struct gve_adminq_create_rx_queue) {
@@ -369,7 +371,7 @@ static int gve_adminq_create_rx_queue(struct gve_priv *priv, u32 queue_index)
.queue_resources_addr = cpu_to_be64(rx->q_resources_bus),
.rx_desc_ring_addr = cpu_to_be64(rx->desc.bus),
.rx_data_ring_addr = cpu_to_be64(rx->data.data_bus),
- .queue_page_list_id = cpu_to_be32(rx->data.qpl->id),
+ .queue_page_list_id = cpu_to_be32(qpl_id),
};
err = gve_adminq_issue_cmd(priv, &cmd);
@@ -514,11 +516,11 @@ int gve_adminq_describe_device(struct gve_priv *priv)
mac = descriptor->mac;
dev_info(&priv->pdev->dev, "MAC addr: %pM\n", mac);
priv->tx_pages_per_qpl = be16_to_cpu(descriptor->tx_pages_per_qpl);
- priv->rx_pages_per_qpl = be16_to_cpu(descriptor->rx_pages_per_qpl);
- if (priv->rx_pages_per_qpl < priv->rx_desc_cnt) {
- dev_err(&priv->pdev->dev, "rx_pages_per_qpl cannot be smaller than rx_desc_cnt, setting rx_desc_cnt down to %d.\n",
- priv->rx_pages_per_qpl);
- priv->rx_desc_cnt = priv->rx_pages_per_qpl;
+ priv->rx_data_slot_cnt = be16_to_cpu(descriptor->rx_pages_per_qpl);
+ if (priv->rx_data_slot_cnt < priv->rx_desc_cnt) {
+ dev_err(&priv->pdev->dev, "rx_data_slot_cnt cannot be smaller than rx_desc_cnt, setting rx_desc_cnt down to %d.\n",
+ priv->rx_data_slot_cnt);
+ priv->rx_desc_cnt = priv->rx_data_slot_cnt;
}
priv->default_num_queues = be16_to_cpu(descriptor->default_num_queues);
dev_opt = (void *)(descriptor + 1);
@@ -72,12 +72,14 @@ struct gve_rx_desc {
} __packed;
static_assert(sizeof(struct gve_rx_desc) == 64);
-/* As with the Tx ring format, the qpl_offset entries below are offsets into an
- * ordered list of registered pages.
+/* If the device supports raw dma addressing then the addr in data slot is
+ * the dma address of the buffer.
+ * If the device only supports registered segments than the addr is a byte
+ * offset into the registered segment (an ordered list of pages) where the
+ * buffer is.
*/
struct gve_rx_data_slot {
- /* byte offset into the rx registered segment of this slot */
- __be64 qpl_offset;
+ __be64 addr;
};
/* GVE Recive Packet Descriptor Seq No */
@@ -596,6 +596,7 @@ int gve_alloc_page(struct gve_priv *priv, struct device *dev,
if (dma_mapping_error(dev, *dma)) {
priv->dma_mapping_error++;
put_page(*page);
+ *page = NULL;
return -ENOMEM;
}
return 0;
@@ -694,7 +695,7 @@ static int gve_alloc_qpls(struct gve_priv *priv)
}
for (; i < num_qpls; i++) {
err = gve_alloc_queue_page_list(priv, i,
- priv->rx_pages_per_qpl);
+ priv->rx_data_slot_cnt);
if (err)
goto free_qpls;
}
@@ -6,6 +6,7 @@
#include "gve.h"
#include "gve_adminq.h"
+#include "linux/device-mapper.h"
#include <linux/etherdevice.h>
static void gve_rx_remove_from_block(struct gve_priv *priv, int queue_idx)
@@ -16,12 +17,22 @@ static void gve_rx_remove_from_block(struct gve_priv *priv, int queue_idx)
block->rx = NULL;
}
+static void gve_rx_free_buffer(struct device *dev,
+ struct gve_rx_slot_page_info *page_info,
+ struct gve_rx_data_slot *data_slot)
+{
+ dma_addr_t dma = (dma_addr_t)(be64_to_cpu(data_slot->addr) -
+ page_info->page_offset);
+
+ gve_free_page(dev, page_info->page, dma, DMA_FROM_DEVICE);
+}
+
static void gve_rx_free_ring(struct gve_priv *priv, int idx)
{
struct gve_rx_ring *rx = &priv->rx[idx];
struct device *dev = &priv->pdev->dev;
+ u32 slots = rx->mask + 1;
size_t bytes;
- u32 slots;
gve_rx_remove_from_block(priv, idx);
@@ -33,11 +44,18 @@ static void gve_rx_free_ring(struct gve_priv *priv, int idx)
rx->q_resources, rx->q_resources_bus);
rx->q_resources = NULL;
- gve_unassign_qpl(priv, rx->data.qpl->id);
- rx->data.qpl = NULL;
+ if (rx->data.raw_addressing) {
+ int i;
+
+ for (i = 0; i < slots; i++)
+ gve_rx_free_buffer(dev, &rx->data.page_info[i],
+ &rx->data.data_ring[i]);
+ } else {
+ gve_unassign_qpl(priv, rx->data.qpl->id);
+ rx->data.qpl = NULL;
+ }
kvfree(rx->data.page_info);
- slots = rx->mask + 1;
bytes = sizeof(*rx->data.data_ring) * slots;
dma_free_coherent(dev, bytes, rx->data.data_ring,
rx->data.data_bus);
@@ -52,13 +70,14 @@ static void gve_setup_rx_buffer(struct gve_rx_slot_page_info *page_info,
page_info->page = page;
page_info->page_offset = 0;
page_info->page_address = page_address(page);
- slot->qpl_offset = cpu_to_be64(addr);
+ slot->addr = cpu_to_be64(addr);
}
static int gve_prefill_rx_pages(struct gve_rx_ring *rx)
{
struct gve_priv *priv = rx->gve;
u32 slots;
+ int err;
int i;
/* Allocate one page per Rx queue slot. Each page is split into two
@@ -71,12 +90,30 @@ static int gve_prefill_rx_pages(struct gve_rx_ring *rx)
if (!rx->data.page_info)
return -ENOMEM;
- rx->data.qpl = gve_assign_rx_qpl(priv);
-
+ if (!rx->data.raw_addressing)
+ rx->data.qpl = gve_assign_rx_qpl(priv);
for (i = 0; i < slots; i++) {
- struct page *page = rx->data.qpl->pages[i];
- dma_addr_t addr = i * PAGE_SIZE;
+ struct page *page;
+ dma_addr_t addr;
+
+ if (rx->data.raw_addressing) {
+ err = gve_alloc_page(priv, &priv->pdev->dev, &page,
+ &addr, DMA_FROM_DEVICE);
+ if (err) {
+ int j;
+ u64_stats_update_begin(&rx->statss);
+ rx->rx_buf_alloc_fail++;
+ u64_stats_update_end(&rx->statss);
+ for (j = 0; j < i; j++)
+ gve_free_page(&priv->pdev->dev, page,
+ addr, DMA_FROM_DEVICE);
+ return err;
+ }
+ } else {
+ page = rx->data.qpl->pages[i];
+ addr = i * PAGE_SIZE;
+ }
gve_setup_rx_buffer(&rx->data.page_info[i],
&rx->data.data_ring[i], addr, page);
}
@@ -110,8 +147,9 @@ static int gve_rx_alloc_ring(struct gve_priv *priv, int idx)
rx->gve = priv;
rx->q_num = idx;
- slots = priv->rx_pages_per_qpl;
+ slots = priv->rx_data_slot_cnt;
rx->mask = slots - 1;
+ rx->data.raw_addressing = priv->raw_addressing;
/* alloc rx data ring */
bytes = sizeof(*rx->data.data_ring) * slots;
@@ -156,8 +194,8 @@ static int gve_rx_alloc_ring(struct gve_priv *priv, int idx)
err = -ENOMEM;
goto abort_with_q_resources;
}
- rx->mask = slots - 1;
rx->cnt = 0;
+ rx->db_threshold = priv->rx_desc_cnt / 2;
rx->desc.seqno = 1;
gve_rx_add_to_block(priv, idx);
@@ -251,8 +289,7 @@ static struct sk_buff *gve_rx_copy(struct gve_rx_ring *rx,
return skb;
}
-static struct sk_buff *gve_rx_add_frags(struct net_device *dev,
- struct napi_struct *napi,
+static struct sk_buff *gve_rx_add_frags(struct napi_struct *napi,
struct gve_rx_slot_page_info *page_info,
u16 len)
{
@@ -268,14 +305,49 @@ static struct sk_buff *gve_rx_add_frags(struct net_device *dev,
return skb;
}
+static int gve_rx_alloc_buffer(struct gve_priv *priv, struct device *dev,
+ struct gve_rx_slot_page_info *page_info,
+ struct gve_rx_data_slot *data_slot,
+ struct gve_rx_ring *rx)
+{
+ struct page *page;
+ dma_addr_t dma;
+ int err;
+
+ err = gve_alloc_page(priv, dev, &page, &dma, DMA_FROM_DEVICE);
+ if (err) {
+ u64_stats_update_begin(&rx->statss);
+ rx->rx_buf_alloc_fail++;
+ u64_stats_update_end(&rx->statss);
+ return err;
+ }
+
+ gve_setup_rx_buffer(page_info, data_slot, dma, page);
+ return 0;
+}
+
static void gve_rx_flip_buff(struct gve_rx_slot_page_info *page_info,
struct gve_rx_data_slot *data_ring)
{
- u64 addr = be64_to_cpu(data_ring->qpl_offset);
+ u64 addr = be64_to_cpu(data_ring->addr);
page_info->page_offset ^= PAGE_SIZE / 2;
addr ^= PAGE_SIZE / 2;
- data_ring->qpl_offset = cpu_to_be64(addr);
+ data_ring->addr = cpu_to_be64(addr);
+}
+
+static struct sk_buff *
+gve_rx_raw_addressing(struct device *dev, struct net_device *netdev,
+ struct gve_rx_slot_page_info *page_info, u16 len,
+ struct napi_struct *napi,
+ struct gve_rx_data_slot *data_slot)
+{
+ struct sk_buff *skb = gve_rx_add_frags(napi, page_info, len);
+
+ if (!skb)
+ return NULL;
+
+ return skb;
}
static bool gve_rx(struct gve_rx_ring *rx, struct gve_rx_desc *rx_desc,
@@ -285,7 +357,9 @@ static bool gve_rx(struct gve_rx_ring *rx, struct gve_rx_desc *rx_desc,
struct gve_priv *priv = rx->gve;
struct napi_struct *napi = &priv->ntfy_blocks[rx->ntfy_id].napi;
struct net_device *dev = priv->dev;
- struct sk_buff *skb;
+ struct gve_rx_data_slot *data_slot;
+ struct sk_buff *skb = NULL;
+ dma_addr_t page_bus;
int pagecount;
u16 len;
@@ -294,18 +368,18 @@ static bool gve_rx(struct gve_rx_ring *rx, struct gve_rx_desc *rx_desc,
u64_stats_update_begin(&rx->statss);
rx->rx_desc_err_dropped_pkt++;
u64_stats_update_end(&rx->statss);
- return true;
+ return false;
}
len = be16_to_cpu(rx_desc->len) - GVE_RX_PAD;
page_info = &rx->data.page_info[idx];
- dma_sync_single_for_cpu(&priv->pdev->dev, rx->data.qpl->page_buses[idx],
- PAGE_SIZE, DMA_FROM_DEVICE);
- /* gvnic can only receive into registered segments. If the buffer
- * can't be recycled, our only choice is to copy the data out of
- * it so that we can return it to the device.
- */
+ data_slot = &rx->data.data_ring[idx];
+ page_bus = (rx->data.raw_addressing) ?
+ be64_to_cpu(data_slot->addr) - page_info->page_offset :
+ rx->data.qpl->page_buses[idx];
+ dma_sync_single_for_cpu(&priv->pdev->dev, page_bus,
+ PAGE_SIZE, DMA_FROM_DEVICE);
if (PAGE_SIZE == 4096) {
if (len <= priv->rx_copybreak) {
@@ -316,6 +390,12 @@ static bool gve_rx(struct gve_rx_ring *rx, struct gve_rx_desc *rx_desc,
u64_stats_update_end(&rx->statss);
goto have_skb;
}
+ if (rx->data.raw_addressing) {
+ skb = gve_rx_raw_addressing(&priv->pdev->dev, dev,
+ page_info, len, napi,
+ data_slot);
+ goto have_skb;
+ }
if (unlikely(!gve_can_recycle_pages(dev))) {
skb = gve_rx_copy(rx, dev, napi, page_info, len);
goto have_skb;
@@ -326,12 +406,12 @@ static bool gve_rx(struct gve_rx_ring *rx, struct gve_rx_desc *rx_desc,
* the page fragment to a new SKB and pass it up the
* stack.
*/
- skb = gve_rx_add_frags(dev, napi, page_info, len);
+ skb = gve_rx_add_frags(napi, page_info, len);
if (!skb) {
u64_stats_update_begin(&rx->statss);
rx->rx_skb_alloc_fail++;
u64_stats_update_end(&rx->statss);
- return true;
+ return false;
}
/* Make sure the kernel stack can't release the page */
get_page(page_info->page);
@@ -347,7 +427,12 @@ static bool gve_rx(struct gve_rx_ring *rx, struct gve_rx_desc *rx_desc,
return false;
}
} else {
- skb = gve_rx_copy(rx, dev, napi, page_info, len);
+ if (rx->data.raw_addressing)
+ skb = gve_rx_copy(rx, dev, napi, page_info, len);
+ else
+ skb = gve_rx_raw_addressing(&priv->pdev->dev, dev,
+ page_info, len, napi,
+ data_slot);
}
have_skb:
@@ -358,7 +443,7 @@ static bool gve_rx(struct gve_rx_ring *rx, struct gve_rx_desc *rx_desc,
u64_stats_update_begin(&rx->statss);
rx->rx_skb_alloc_fail++;
u64_stats_update_end(&rx->statss);
- return true;
+ return false;
}
if (likely(feat & NETIF_F_RXCSUM)) {
@@ -399,19 +484,41 @@ static bool gve_rx_work_pending(struct gve_rx_ring *rx)
return (GVE_SEQNO(flags_seq) == rx->desc.seqno);
}
+static bool gve_rx_refill_buffers(struct gve_priv *priv, struct gve_rx_ring *rx)
+{
+ u32 fill_cnt = rx->fill_cnt;
+
+ while ((fill_cnt & rx->mask) != (rx->cnt & rx->mask)) {
+ u32 idx = fill_cnt & rx->mask;
+ struct gve_rx_slot_page_info *page_info = &rx->data.page_info[idx];
+ struct gve_rx_data_slot *data_slot = &rx->data.data_ring[idx];
+ struct device *dev = &priv->pdev->dev;
+
+ gve_rx_free_buffer(dev, page_info, data_slot);
+ page_info->page = NULL;
+ if (gve_rx_alloc_buffer(priv, dev, page_info, data_slot, rx))
+ break;
+ fill_cnt++;
+ }
+ rx->fill_cnt = fill_cnt;
+ return true;
+}
+
bool gve_clean_rx_done(struct gve_rx_ring *rx, int budget,
netdev_features_t feat)
{
struct gve_priv *priv = rx->gve;
+ u32 work_done = 0, packets = 0;
struct gve_rx_desc *desc;
u32 cnt = rx->cnt;
u32 idx = cnt & rx->mask;
- u32 work_done = 0;
u64 bytes = 0;
desc = rx->desc.desc_ring + idx;
while ((GVE_SEQNO(desc->flags_seq) == rx->desc.seqno) &&
work_done < budget) {
+ bool dropped;
+
netif_info(priv, rx_status, priv->dev,
"[%d] idx=%d desc=%p desc->flags_seq=0x%x\n",
rx->q_num, idx, desc, desc->flags_seq);
@@ -419,9 +526,11 @@ bool gve_clean_rx_done(struct gve_rx_ring *rx, int budget,
"[%d] seqno=%d rx->desc.seqno=%d\n",
rx->q_num, GVE_SEQNO(desc->flags_seq),
rx->desc.seqno);
- bytes += be16_to_cpu(desc->len) - GVE_RX_PAD;
- if (!gve_rx(rx, desc, feat, idx))
- gve_schedule_reset(priv);
+ dropped = !gve_rx(rx, desc, feat, idx);
+ if (!dropped) {
+ bytes += be16_to_cpu(desc->len) - GVE_RX_PAD;
+ packets++;
+ }
cnt++;
idx = cnt & rx->mask;
desc = rx->desc.desc_ring + idx;
@@ -433,11 +542,21 @@ bool gve_clean_rx_done(struct gve_rx_ring *rx, int budget,
return false;
u64_stats_update_begin(&rx->statss);
- rx->rpackets += work_done;
+ rx->rpackets += packets;
rx->rbytes += bytes;
u64_stats_update_end(&rx->statss);
rx->cnt = cnt;
- rx->fill_cnt += work_done;
+ /* restock ring slots */
+ if (!rx->data.raw_addressing) {
+ /* In QPL mode buffs are refilled as the desc are processed */
+ rx->fill_cnt += work_done;
+ } else if (rx->fill_cnt - cnt <= rx->db_threshold) {
+ /* In raw addressing mode buffs are only refilled if the avail
+ * falls below a threshold.
+ */
+ if (!gve_rx_refill_buffers(priv, rx))
+ return false;
+ }
gve_rx_write_doorbell(priv, rx);
return gve_rx_work_pending(rx);