Add support for passing traffic.
Signed-off-by: Catherine Sullivan <csully@google.com>
Signed-off-by: Sagi Shahar <sagis@google.com>
Signed-off-by: Jon Olson <jonolson@google.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: Luigi Rizzo <lrizzo@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
- See description below
- Interrupts
- See supported interrupts below
+ - Transmit and Receive Queues
+ - See description below
Registers
---------
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
The notification block interrupts are used to tell the driver to poll
the queues associated with that interrupt.
+
+The handler for these irqs schedule the napi for that block to run
+and poll the queues.
+
+Traffic Queues
+--------------
+gVNIC's queues are composed of a descriptor ring and a buffer and are
+assigned to a notification block.
+
+The descriptor rings are power-of-two-sized ring buffers consisting of
+fixed-size descriptors. They advance their head pointer using a __be32
+doorbell located in Bar2. The tail pointers are advanced by consuming
+descriptors in-order and updating a __be32 counter. Both the doorbell
+and the counter overflow to zero.
+
+Each queue's buffers must be registered in advance with the device as a
+queue page list, and packet data can only be put in those pages.
+
+Transmit
+~~~~~~~~
+gve maps the buffers for transmit rings into a FIFO and copies the packets
+into the FIFO before sending them to the NIC.
+
+Receive
+~~~~~~~
+The buffers for receive rings are put into a data ring that is the same
+length as the descriptor ring and the head and tail pointers advance over
+the rings together.
# Makefile for the Google virtual Ethernet (gve) driver
obj-$(CONFIG_GVE) += gve.o
-gve-objs := gve_main.o gve_adminq.o
+gve-objs := gve_main.o gve_tx.o gve_rx.o gve_adminq.o
#include <linux/dma-mapping.h>
#include <linux/netdevice.h>
#include <linux/pci.h>
+#include <linux/u64_stats_sync.h>
+#include "gve_desc.h"
#ifndef PCI_VENDOR_ID_GOOGLE
#define PCI_VENDOR_ID_GOOGLE 0x1ae0
#define GVE_REGISTER_BAR 0
#define GVE_DOORBELL_BAR 2
-/* 1 for management */
+/* Driver can alloc up to 2 segments for the header and 2 for the payload. */
+#define GVE_TX_MAX_IOVEC 4
+/* 1 for management, 1 for rx, 1 for tx */
#define GVE_MIN_MSIX 3
+/* Each slot in the desc ring has a 1:1 mapping to a slot in the data ring */
+struct gve_rx_desc_queue {
+ struct gve_rx_desc *desc_ring; /* the descriptor ring */
+ dma_addr_t bus; /* the bus for the desc_ring */
+ u32 cnt; /* free-running total number of completed packets */
+ u32 fill_cnt; /* free-running total number of descriptors posted */
+ u32 mask; /* masks the cnt to the size of the ring */
+ u8 seqno; /* the next expected seqno for this desc*/
+};
+
+/* The page info for a single slot in the RX data queue */
+struct gve_rx_slot_page_info {
+ struct page *page;
+ void *page_address;
+ u32 page_offset; /* offset to write to in page */
+};
+
+/* A list of pages registered with the device during setup and used by a queue
+ * as buffers
+ */
+struct gve_queue_page_list {
+ u32 id; /* unique id */
+ u32 num_entries;
+ struct page **pages; /* list of num_entries pages */
+ dma_addr_t *page_buses; /* the dma addrs of the pages */
+};
+
+/* Each slot in the data ring has a 1:1 mapping to a slot in the desc ring */
+struct gve_rx_data_queue {
+ struct gve_rx_data_slot *data_ring; /* read by NIC */
+ 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 */
+ u32 mask; /* masks the cnt to the size of the ring */
+ u32 cnt; /* free-running total number of completed packets */
+};
+
+struct gve_priv;
+
+/* An RX ring that contains a power-of-two sized desc and data ring. */
+struct gve_rx_ring {
+ struct gve_priv *gve;
+ struct gve_rx_desc_queue desc;
+ struct gve_rx_data_queue data;
+ u64 rbytes; /* free-running bytes received */
+ u64 rpackets; /* free-running packets received */
+ u32 q_num; /* queue index */
+ u32 ntfy_id; /* notification block index */
+ struct gve_queue_resources *q_resources; /* head and tail pointer idx */
+ dma_addr_t q_resources_bus; /* dma address for the queue resources */
+ struct u64_stats_sync statss; /* sync stats for 32bit archs */
+};
+
+/* A TX desc ring entry */
+union gve_tx_desc {
+ struct gve_tx_pkt_desc pkt; /* first desc for a packet */
+ struct gve_tx_seg_desc seg; /* subsequent descs for a packet */
+};
+
+/* Tracks the memory in the fifo occupied by a segment of a packet */
+struct gve_tx_iovec {
+ u32 iov_offset; /* offset into this segment */
+ u32 iov_len; /* length */
+ u32 iov_padding; /* padding associated with this segment */
+};
+
+/* Tracks the memory in the fifo occupied by the skb. Mapped 1:1 to a desc
+ * ring entry but only used for a pkt_desc not a seg_desc
+ */
+struct gve_tx_buffer_state {
+ struct sk_buff *skb; /* skb for this pkt */
+ struct gve_tx_iovec iov[GVE_TX_MAX_IOVEC]; /* segments of this pkt */
+};
+
+/* A TX buffer - each queue has one */
+struct gve_tx_fifo {
+ void *base; /* address of base of FIFO */
+ u32 size; /* total size */
+ atomic_t available; /* how much space is still available */
+ u32 head; /* offset to write at */
+ struct gve_queue_page_list *qpl; /* QPL mapped into this FIFO */
+};
+
+/* A TX ring that contains a power-of-two sized desc ring and a FIFO buffer */
+struct gve_tx_ring {
+ /* Cacheline 0 -- Accessed & dirtied during transmit */
+ struct gve_tx_fifo tx_fifo;
+ u32 req; /* driver tracked head pointer */
+ u32 done; /* driver tracked tail pointer */
+
+ /* Cacheline 1 -- Accessed & dirtied during gve_clean_tx_done */
+ __be32 last_nic_done ____cacheline_aligned; /* NIC tail pointer */
+ u64 pkt_done; /* free-running - total packets completed */
+ u64 bytes_done; /* free-running - total bytes completed */
+
+ /* Cacheline 2 -- Read-mostly fields */
+ union gve_tx_desc *desc ____cacheline_aligned;
+ struct gve_tx_buffer_state *info; /* Maps 1:1 to a desc */
+ struct netdev_queue *netdev_txq;
+ struct gve_queue_resources *q_resources; /* head and tail pointer idx */
+ u32 mask; /* masks req and done down to queue size */
+
+ /* Slow-path fields */
+ u32 q_num ____cacheline_aligned; /* queue idx */
+ u32 stop_queue; /* count of queue stops */
+ u32 wake_queue; /* count of queue wakes */
+ u32 ntfy_id; /* notification block index */
+ dma_addr_t bus; /* dma address of the descr ring */
+ dma_addr_t q_resources_bus; /* dma address of the queue resources */
+ struct u64_stats_sync statss; /* sync stats for 32bit archs */
+} ____cacheline_aligned;
+
+/* Wraps the info for one irq including the napi struct and the queues
+ * associated with that irq.
+ */
struct gve_notify_block {
__be32 irq_db_index; /* idx into Bar2 - set by device, must be 1st */
char name[IFNAMSIZ + 16]; /* name registered with the kernel */
struct napi_struct napi; /* kernel napi struct for this block */
struct gve_priv *priv;
+ struct gve_tx_ring *tx; /* tx rings on this block */
+ struct gve_rx_ring *rx; /* rx rings on this block */
} ____cacheline_aligned;
+/* Tracks allowed and current queue settings */
+struct gve_queue_config {
+ u16 max_queues;
+ u16 num_queues; /* current */
+};
+
+/* Tracks the available and used qpl IDs */
+struct gve_qpl_config {
+ u32 qpl_map_size; /* map memory size */
+ unsigned long *qpl_id_map; /* bitmap of used qpl ids */
+};
+
struct gve_priv {
struct net_device *dev;
+ struct gve_tx_ring *tx; /* array of tx_cfg.num_queues */
+ struct gve_rx_ring *rx; /* array of rx_cfg.num_queues */
+ struct gve_queue_page_list *qpls; /* array of num qpls */
struct gve_notify_block *ntfy_blocks; /* array of num_ntfy_blks */
dma_addr_t ntfy_block_bus;
struct msix_entry *msix_vectors; /* array of num_ntfy_blks + 1 */
dma_addr_t counter_array_bus;
u16 num_event_counters;
+ 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 */
+ u64 max_registered_pages;
+ u64 num_registered_pages; /* num pages registered with NIC */
+ u32 rx_copybreak; /* copy packets smaller than this */
+ u16 default_num_queues; /* default num queues to set up */
+ struct gve_queue_config tx_cfg;
+ struct gve_queue_config rx_cfg;
+ struct gve_qpl_config qpl_cfg; /* map used QPL ids */
u32 num_ntfy_blks; /* spilt between TX and RX so must be even */
struct gve_registers __iomem *reg_bar0; /* see gve_register.h */
u32 msg_enable; /* level for netif* netdev print macros */
struct pci_dev *pdev;
+ /* metrics */
+ u32 tx_timeo_cnt;
+
/* Admin queue - see gve_adminq.h*/
union gve_adminq_command *adminq;
dma_addr_t adminq_bus_addr;
{
return &priv->db_bar2[be32_to_cpu(block->irq_db_index)];
}
+
+/* Returns the index into ntfy_blocks of the given tx ring's block
+ */
+static inline u32 gve_tx_idx_to_ntfy(struct gve_priv *priv, u32 queue_idx)
+{
+ return queue_idx;
+}
+
+/* Returns the index into ntfy_blocks of the given rx ring's block
+ */
+static inline u32 gve_rx_idx_to_ntfy(struct gve_priv *priv, u32 queue_idx)
+{
+ return (priv->num_ntfy_blks / 2) + queue_idx;
+}
+
+/* Returns the number of tx queue page lists
+ */
+static inline u32 gve_num_tx_qpls(struct gve_priv *priv)
+{
+ return priv->tx_cfg.num_queues;
+}
+
+/* Returns the number of rx queue page lists
+ */
+static inline u32 gve_num_rx_qpls(struct gve_priv *priv)
+{
+ return priv->rx_cfg.num_queues;
+}
+
+/* Returns a pointer to the next available tx qpl in the list of qpls
+ */
+static inline
+struct gve_queue_page_list *gve_assign_tx_qpl(struct gve_priv *priv)
+{
+ int id = find_first_zero_bit(priv->qpl_cfg.qpl_id_map,
+ priv->qpl_cfg.qpl_map_size);
+
+ /* we are out of tx qpls */
+ if (id >= gve_num_tx_qpls(priv))
+ return NULL;
+
+ set_bit(id, priv->qpl_cfg.qpl_id_map);
+ return &priv->qpls[id];
+}
+
+/* Returns a pointer to the next available rx qpl in the list of qpls
+ */
+static inline
+struct gve_queue_page_list *gve_assign_rx_qpl(struct gve_priv *priv)
+{
+ int id = find_next_zero_bit(priv->qpl_cfg.qpl_id_map,
+ priv->qpl_cfg.qpl_map_size,
+ gve_num_tx_qpls(priv));
+
+ /* we are out of rx qpls */
+ if (id == priv->qpl_cfg.qpl_map_size)
+ return NULL;
+
+ set_bit(id, priv->qpl_cfg.qpl_id_map);
+ return &priv->qpls[id];
+}
+
+/* Unassigns the qpl with the given id
+ */
+static inline void gve_unassign_qpl(struct gve_priv *priv, int id)
+{
+ clear_bit(id, priv->qpl_cfg.qpl_id_map);
+}
+
+/* Returns the correct dma direction for tx and rx qpls
+ */
+static inline enum dma_data_direction gve_qpl_dma_dir(struct gve_priv *priv,
+ int id)
+{
+ if (id < gve_num_tx_qpls(priv))
+ return DMA_TO_DEVICE;
+ else
+ return DMA_FROM_DEVICE;
+}
+
+/* Returns true if the max mtu allows page recycling */
+static inline bool gve_can_recycle_pages(struct net_device *dev)
+{
+ /* We can't recycle the pages if we can't fit a packet into half a
+ * page.
+ */
+ return dev->max_mtu <= PAGE_SIZE / 2;
+}
+
+/* buffers */
+int gve_alloc_page(struct device *dev, struct page **page, dma_addr_t *dma,
+ enum dma_data_direction);
+void gve_free_page(struct device *dev, struct page *page, dma_addr_t dma,
+ enum dma_data_direction);
+/* tx handling */
+netdev_tx_t gve_tx(struct sk_buff *skb, struct net_device *dev);
+bool gve_tx_poll(struct gve_notify_block *block, int budget);
+int gve_tx_alloc_rings(struct gve_priv *priv);
+void gve_tx_free_rings(struct gve_priv *priv);
+__be32 gve_tx_load_event_counter(struct gve_priv *priv,
+ struct gve_tx_ring *tx);
+/* rx handling */
+void gve_rx_write_doorbell(struct gve_priv *priv, struct gve_rx_ring *rx);
+bool gve_rx_poll(struct gve_notify_block *block, int budget);
+int gve_rx_alloc_rings(struct gve_priv *priv);
+void gve_rx_free_rings(struct gve_priv *priv);
+bool gve_clean_rx_done(struct gve_rx_ring *rx, int budget,
+ netdev_features_t feat);
#endif /* _GVE_H_ */
return gve_adminq_execute_cmd(priv, &cmd);
}
+int gve_adminq_create_tx_queue(struct gve_priv *priv, u32 queue_index)
+{
+ struct gve_tx_ring *tx = &priv->tx[queue_index];
+ union gve_adminq_command cmd;
+
+ memset(&cmd, 0, sizeof(cmd));
+ cmd.opcode = cpu_to_be32(GVE_ADMINQ_CREATE_TX_QUEUE);
+ cmd.create_tx_queue = (struct gve_adminq_create_tx_queue) {
+ .queue_id = cpu_to_be32(queue_index),
+ .reserved = 0,
+ .queue_resources_addr = cpu_to_be64(tx->q_resources_bus),
+ .tx_ring_addr = cpu_to_be64(tx->bus),
+ .queue_page_list_id = cpu_to_be32(tx->tx_fifo.qpl->id),
+ .ntfy_id = cpu_to_be32(tx->ntfy_id),
+ };
+
+ return gve_adminq_execute_cmd(priv, &cmd);
+}
+
+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;
+
+ 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) {
+ .queue_id = cpu_to_be32(queue_index),
+ .index = cpu_to_be32(queue_index),
+ .reserved = 0,
+ .ntfy_id = cpu_to_be32(rx->ntfy_id),
+ .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),
+ };
+
+ return gve_adminq_execute_cmd(priv, &cmd);
+}
+
+int gve_adminq_destroy_tx_queue(struct gve_priv *priv, u32 queue_index)
+{
+ union gve_adminq_command cmd;
+
+ memset(&cmd, 0, sizeof(cmd));
+ cmd.opcode = cpu_to_be32(GVE_ADMINQ_DESTROY_TX_QUEUE);
+ cmd.destroy_tx_queue = (struct gve_adminq_destroy_tx_queue) {
+ .queue_id = cpu_to_be32(queue_index),
+ };
+
+ return gve_adminq_execute_cmd(priv, &cmd);
+}
+
+int gve_adminq_destroy_rx_queue(struct gve_priv *priv, u32 queue_index)
+{
+ union gve_adminq_command cmd;
+
+ memset(&cmd, 0, sizeof(cmd));
+ cmd.opcode = cpu_to_be32(GVE_ADMINQ_DESTROY_RX_QUEUE);
+ cmd.destroy_rx_queue = (struct gve_adminq_destroy_rx_queue) {
+ .queue_id = cpu_to_be32(queue_index),
+ };
+
+ return gve_adminq_execute_cmd(priv, &cmd);
+}
+
int gve_adminq_describe_device(struct gve_priv *priv)
{
struct gve_device_descriptor *descriptor;
if (err)
goto free_device_descriptor;
+ priv->tx_desc_cnt = be16_to_cpu(descriptor->tx_queue_entries);
+ if (priv->tx_desc_cnt * sizeof(priv->tx->desc[0]) < PAGE_SIZE) {
+ netif_err(priv, drv, priv->dev, "Tx desc count %d too low\n",
+ priv->tx_desc_cnt);
+ err = -EINVAL;
+ goto free_device_descriptor;
+ }
+ priv->rx_desc_cnt = be16_to_cpu(descriptor->rx_queue_entries);
+ if (priv->rx_desc_cnt * sizeof(priv->rx->desc.desc_ring[0])
+ < PAGE_SIZE ||
+ priv->rx_desc_cnt * sizeof(priv->rx->data.data_ring[0])
+ < PAGE_SIZE) {
+ netif_err(priv, drv, priv->dev, "Rx desc count %d too low\n",
+ priv->rx_desc_cnt);
+ err = -EINVAL;
+ goto free_device_descriptor;
+ }
+ priv->max_registered_pages =
+ be64_to_cpu(descriptor->max_registered_pages);
mtu = be16_to_cpu(descriptor->mtu);
if (mtu < ETH_MIN_MTU) {
netif_err(priv, drv, priv->dev, "MTU %d below minimum MTU\n",
ether_addr_copy(priv->dev->dev_addr, descriptor->mac);
mac = descriptor->mac;
netif_info(priv, drv, priv->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) {
+ netif_err(priv, drv, priv->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->default_num_queues = be16_to_cpu(descriptor->default_num_queues);
free_device_descriptor:
dma_free_coherent(&priv->pdev->dev, sizeof(*descriptor), descriptor,
return err;
}
+int gve_adminq_register_page_list(struct gve_priv *priv,
+ struct gve_queue_page_list *qpl)
+{
+ struct device *hdev = &priv->pdev->dev;
+ u32 num_entries = qpl->num_entries;
+ u32 size = num_entries * sizeof(qpl->page_buses[0]);
+ union gve_adminq_command cmd;
+ dma_addr_t page_list_bus;
+ __be64 *page_list;
+ int err;
+ int i;
+
+ memset(&cmd, 0, sizeof(cmd));
+ page_list = dma_alloc_coherent(hdev, size, &page_list_bus, GFP_KERNEL);
+ if (!page_list)
+ return -ENOMEM;
+
+ for (i = 0; i < num_entries; i++)
+ page_list[i] = cpu_to_be64(qpl->page_buses[i]);
+
+ cmd.opcode = cpu_to_be32(GVE_ADMINQ_REGISTER_PAGE_LIST);
+ cmd.reg_page_list = (struct gve_adminq_register_page_list) {
+ .page_list_id = cpu_to_be32(qpl->id),
+ .num_pages = cpu_to_be32(num_entries),
+ .page_address_list_addr = cpu_to_be64(page_list_bus),
+ };
+
+ err = gve_adminq_execute_cmd(priv, &cmd);
+ dma_free_coherent(hdev, size, page_list, page_list_bus);
+ return err;
+}
+
+int gve_adminq_unregister_page_list(struct gve_priv *priv, u32 page_list_id)
+{
+ union gve_adminq_command cmd;
+
+ memset(&cmd, 0, sizeof(cmd));
+ cmd.opcode = cpu_to_be32(GVE_ADMINQ_UNREGISTER_PAGE_LIST);
+ cmd.unreg_page_list = (struct gve_adminq_unregister_page_list) {
+ .page_list_id = cpu_to_be32(page_list_id),
+ };
+
+ return gve_adminq_execute_cmd(priv, &cmd);
+}
+
int gve_adminq_set_mtu(struct gve_priv *priv, u64 mtu)
{
union gve_adminq_command cmd;
enum gve_adminq_opcodes {
GVE_ADMINQ_DESCRIBE_DEVICE = 0x1,
GVE_ADMINQ_CONFIGURE_DEVICE_RESOURCES = 0x2,
+ GVE_ADMINQ_REGISTER_PAGE_LIST = 0x3,
+ GVE_ADMINQ_UNREGISTER_PAGE_LIST = 0x4,
+ GVE_ADMINQ_CREATE_TX_QUEUE = 0x5,
+ GVE_ADMINQ_CREATE_RX_QUEUE = 0x6,
+ GVE_ADMINQ_DESTROY_TX_QUEUE = 0x7,
+ GVE_ADMINQ_DESTROY_RX_QUEUE = 0x8,
GVE_ADMINQ_DECONFIGURE_DEVICE_RESOURCES = 0x9,
GVE_ADMINQ_SET_DRIVER_PARAMETER = 0xB,
};
static_assert(sizeof(struct gve_adminq_configure_device_resources) == 32);
+struct gve_adminq_register_page_list {
+ __be32 page_list_id;
+ __be32 num_pages;
+ __be64 page_address_list_addr;
+};
+
+static_assert(sizeof(struct gve_adminq_register_page_list) == 16);
+
+struct gve_adminq_unregister_page_list {
+ __be32 page_list_id;
+};
+
+static_assert(sizeof(struct gve_adminq_unregister_page_list) == 4);
+
+struct gve_adminq_create_tx_queue {
+ __be32 queue_id;
+ __be32 reserved;
+ __be64 queue_resources_addr;
+ __be64 tx_ring_addr;
+ __be32 queue_page_list_id;
+ __be32 ntfy_id;
+};
+
+static_assert(sizeof(struct gve_adminq_create_tx_queue) == 32);
+
+struct gve_adminq_create_rx_queue {
+ __be32 queue_id;
+ __be32 index;
+ __be32 reserved;
+ __be32 ntfy_id;
+ __be64 queue_resources_addr;
+ __be64 rx_desc_ring_addr;
+ __be64 rx_data_ring_addr;
+ __be32 queue_page_list_id;
+ u8 padding[4];
+};
+
+static_assert(sizeof(struct gve_adminq_create_rx_queue) == 48);
+
+/* Queue resources that are shared with the device */
+struct gve_queue_resources {
+ union {
+ struct {
+ __be32 db_index; /* Device -> Guest */
+ __be32 counter_index; /* Device -> Guest */
+ };
+ u8 reserved[64];
+ };
+};
+
+static_assert(sizeof(struct gve_queue_resources) == 64);
+
+struct gve_adminq_destroy_tx_queue {
+ __be32 queue_id;
+};
+
+static_assert(sizeof(struct gve_adminq_destroy_tx_queue) == 4);
+
+struct gve_adminq_destroy_rx_queue {
+ __be32 queue_id;
+};
+
+static_assert(sizeof(struct gve_adminq_destroy_rx_queue) == 4);
+
/* GVE Set Driver Parameter Types */
enum gve_set_driver_param_types {
GVE_SET_PARAM_MTU = 0x1,
union {
struct gve_adminq_configure_device_resources
configure_device_resources;
+ struct gve_adminq_create_tx_queue create_tx_queue;
+ struct gve_adminq_create_rx_queue create_rx_queue;
+ struct gve_adminq_destroy_tx_queue destroy_tx_queue;
+ struct gve_adminq_destroy_rx_queue destroy_rx_queue;
struct gve_adminq_describe_device describe_device;
+ struct gve_adminq_register_page_list reg_page_list;
+ struct gve_adminq_unregister_page_list unreg_page_list;
struct gve_adminq_set_driver_parameter set_driver_param;
};
};
dma_addr_t db_array_bus_addr,
u32 num_ntfy_blks);
int gve_adminq_deconfigure_device_resources(struct gve_priv *priv);
+int gve_adminq_create_tx_queue(struct gve_priv *priv, u32 queue_id);
+int gve_adminq_destroy_tx_queue(struct gve_priv *priv, u32 queue_id);
+int gve_adminq_create_rx_queue(struct gve_priv *priv, u32 queue_id);
+int gve_adminq_destroy_rx_queue(struct gve_priv *priv, u32 queue_id);
+int gve_adminq_register_page_list(struct gve_priv *priv,
+ struct gve_queue_page_list *qpl);
+int gve_adminq_unregister_page_list(struct gve_priv *priv, u32 page_list_id);
int gve_adminq_set_mtu(struct gve_priv *priv, u64 mtu);
#endif /* _GVE_ADMINQ_H */
--- /dev/null
+/* SPDX-License-Identifier: (GPL-2.0 OR MIT)
+ * Google virtual Ethernet (gve) driver
+ *
+ * Copyright (C) 2015-2019 Google, Inc.
+ */
+
+/* GVE Transmit Descriptor formats */
+
+#ifndef _GVE_DESC_H_
+#define _GVE_DESC_H_
+
+#include <linux/build_bug.h>
+
+/* A note on seg_addrs
+ *
+ * Base addresses encoded in seg_addr are not assumed to be physical
+ * addresses. The ring format assumes these come from some linear address
+ * space. This could be physical memory, kernel virtual memory, user virtual
+ * memory. gVNIC uses lists of registered pages. Each queue is assumed
+ * to be associated with a single such linear address space to ensure a
+ * consistent meaning for seg_addrs posted to its rings.
+ */
+
+struct gve_tx_pkt_desc {
+ u8 type_flags; /* desc type is lower 4 bits, flags upper */
+ u8 l4_csum_offset; /* relative offset of L4 csum word */
+ u8 l4_hdr_offset; /* Offset of start of L4 headers in packet */
+ u8 desc_cnt; /* Total descriptors for this packet */
+ __be16 len; /* Total length of this packet (in bytes) */
+ __be16 seg_len; /* Length of this descriptor's segment */
+ __be64 seg_addr; /* Base address (see note) of this segment */
+} __packed;
+
+struct gve_tx_seg_desc {
+ u8 type_flags; /* type is lower 4 bits, flags upper */
+ u8 l3_offset; /* TSO: 2 byte units to start of IPH */
+ __be16 reserved;
+ __be16 mss; /* TSO MSS */
+ __be16 seg_len;
+ __be64 seg_addr;
+} __packed;
+
+/* GVE Transmit Descriptor Types */
+#define GVE_TXD_STD (0x0 << 4) /* Std with Host Address */
+#define GVE_TXD_TSO (0x1 << 4) /* TSO with Host Address */
+#define GVE_TXD_SEG (0x2 << 4) /* Seg with Host Address */
+
+/* GVE Transmit Descriptor Flags for Std Pkts */
+#define GVE_TXF_L4CSUM BIT(0) /* Need csum offload */
+#define GVE_TXF_TSTAMP BIT(2) /* Timestamp required */
+
+/* GVE Transmit Descriptor Flags for TSO Segs */
+#define GVE_TXSF_IPV6 BIT(1) /* IPv6 TSO */
+
+/* GVE Receive Packet Descriptor */
+/* The start of an ethernet packet comes 2 bytes into the rx buffer.
+ * gVNIC adds this padding so that both the DMA and the L3/4 protocol header
+ * access is aligned.
+ */
+#define GVE_RX_PAD 2
+
+struct gve_rx_desc {
+ u8 padding[48];
+ __be32 rss_hash; /* Receive-side scaling hash (Toeplitz for gVNIC) */
+ __be16 mss;
+ __be16 reserved; /* Reserved to zero */
+ u8 hdr_len; /* Header length (L2-L4) including padding */
+ u8 hdr_off; /* 64-byte-scaled offset into RX_DATA entry */
+ __sum16 csum; /* 1's-complement partial checksum of L3+ bytes */
+ __be16 len; /* Length of the received packet */
+ __be16 flags_seq; /* Flags [15:3] and sequence number [2:0] (1-7) */
+} __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.
+ */
+struct gve_rx_data_slot {
+ /* byte offset into the rx registered segment of this slot */
+ __be64 qpl_offset;
+};
+
+/* GVE Recive Packet Descriptor Seq No */
+#define GVE_SEQNO(x) (be16_to_cpu(x) & 0x7)
+
+/* GVE Recive Packet Descriptor Flags */
+#define GVE_RXFLG(x) cpu_to_be16(1 << (3 + (x)))
+#define GVE_RXF_FRAG GVE_RXFLG(3) /* IP Fragment */
+#define GVE_RXF_IPV4 GVE_RXFLG(4) /* IPv4 */
+#define GVE_RXF_IPV6 GVE_RXFLG(5) /* IPv6 */
+#define GVE_RXF_TCP GVE_RXFLG(6) /* TCP Packet */
+#define GVE_RXF_UDP GVE_RXFLG(7) /* UDP Packet */
+#define GVE_RXF_ERR GVE_RXFLG(8) /* Packet Error Detected */
+
+/* GVE IRQ */
+#define GVE_IRQ_ACK BIT(31)
+#define GVE_IRQ_MASK BIT(30)
+#define GVE_IRQ_EVENT BIT(29)
+
+static inline bool gve_needs_rss(__be16 flag)
+{
+ if (flag & GVE_RXF_FRAG)
+ return false;
+ if (flag & (GVE_RXF_IPV4 | GVE_RXF_IPV6))
+ return true;
+ return false;
+}
+
+static inline u8 gve_next_seqno(u8 seq)
+{
+ return (seq + 1) == 8 ? 1 : seq + 1;
+}
+#endif /* _GVE_DESC_H_ */
#include "gve_adminq.h"
#include "gve_register.h"
+#define GVE_DEFAULT_RX_COPYBREAK (256)
+
#define DEFAULT_MSG_LEVEL (NETIF_MSG_DRV | NETIF_MSG_LINK)
#define GVE_VERSION "1.0.0"
#define GVE_VERSION_PREFIX "GVE-"
static const char gve_version_str[] = GVE_VERSION;
static const char gve_version_prefix[] = GVE_VERSION_PREFIX;
+static void gve_get_stats(struct net_device *dev, struct rtnl_link_stats64 *s)
+{
+ struct gve_priv *priv = netdev_priv(dev);
+ unsigned int start;
+ int ring;
+
+ if (priv->rx) {
+ for (ring = 0; ring < priv->rx_cfg.num_queues; ring++) {
+ do {
+ u64_stats_fetch_begin(&priv->rx[ring].statss);
+ s->rx_packets += priv->rx[ring].rpackets;
+ s->rx_bytes += priv->rx[ring].rbytes;
+ } while (u64_stats_fetch_retry(&priv->rx[ring].statss,
+ start));
+ }
+ }
+ if (priv->tx) {
+ for (ring = 0; ring < priv->tx_cfg.num_queues; ring++) {
+ do {
+ u64_stats_fetch_begin(&priv->tx[ring].statss);
+ s->tx_packets += priv->tx[ring].pkt_done;
+ s->tx_bytes += priv->tx[ring].bytes_done;
+ } while (u64_stats_fetch_retry(&priv->rx[ring].statss,
+ start));
+ }
+ }
+}
+
static int gve_alloc_counter_array(struct gve_priv *priv)
{
priv->counter_array =
static irqreturn_t gve_intr(int irq, void *arg)
{
+ struct gve_notify_block *block = arg;
+ struct gve_priv *priv = block->priv;
+
+ iowrite32be(GVE_IRQ_MASK, gve_irq_doorbell(priv, block));
+ napi_schedule_irqoff(&block->napi);
return IRQ_HANDLED;
}
+static int gve_napi_poll(struct napi_struct *napi, int budget)
+{
+ struct gve_notify_block *block;
+ __be32 __iomem *irq_doorbell;
+ bool reschedule = false;
+ struct gve_priv *priv;
+
+ block = container_of(napi, struct gve_notify_block, napi);
+ priv = block->priv;
+
+ if (block->tx)
+ reschedule |= gve_tx_poll(block, budget);
+ if (block->rx)
+ reschedule |= gve_rx_poll(block, budget);
+
+ if (reschedule)
+ return budget;
+
+ napi_complete(napi);
+ irq_doorbell = gve_irq_doorbell(priv, block);
+ iowrite32be(GVE_IRQ_ACK | GVE_IRQ_EVENT, irq_doorbell);
+
+ /* Double check we have no extra work.
+ * Ensure unmask synchronizes with checking for work.
+ */
+ dma_rmb();
+ if (block->tx)
+ reschedule |= gve_tx_poll(block, -1);
+ if (block->rx)
+ reschedule |= gve_rx_poll(block, -1);
+ if (reschedule && napi_reschedule(napi))
+ iowrite32be(GVE_IRQ_MASK, irq_doorbell);
+
+ return 0;
+}
+
static int gve_alloc_notify_blocks(struct gve_priv *priv)
{
int num_vecs_requested = priv->num_ntfy_blks + 1;
goto abort_with_msix_vectors;
}
if (vecs_enabled != num_vecs_requested) {
- priv->num_ntfy_blks = (vecs_enabled - 1) & ~0x1;
+ int new_num_ntfy_blks = (vecs_enabled - 1) & ~0x1;
+ int vecs_per_type = new_num_ntfy_blks / 2;
+ int vecs_left = new_num_ntfy_blks % 2;
+
+ priv->num_ntfy_blks = new_num_ntfy_blks;
+ priv->tx_cfg.max_queues = min_t(int, priv->tx_cfg.max_queues,
+ vecs_per_type);
+ priv->rx_cfg.max_queues = min_t(int, priv->rx_cfg.max_queues,
+ vecs_per_type + vecs_left);
dev_err(&priv->pdev->dev,
- "Only received %d msix. Lowering number of notification blocks to %d\n",
- vecs_enabled, priv->num_ntfy_blks);
+ "Could not enable desired msix, only enabled %d, adjusting tx max queues to %d, and rx max queues to %d\n",
+ vecs_enabled, priv->tx_cfg.max_queues,
+ priv->rx_cfg.max_queues);
+ if (priv->tx_cfg.num_queues > priv->tx_cfg.max_queues)
+ priv->tx_cfg.num_queues = priv->tx_cfg.max_queues;
+ if (priv->rx_cfg.num_queues > priv->rx_cfg.max_queues)
+ priv->rx_cfg.num_queues = priv->rx_cfg.max_queues;
}
/* Half the notification blocks go to TX and half to RX */
active_cpus = min_t(int, priv->num_ntfy_blks / 2, num_online_cpus());
gve_clear_device_resources_ok(priv);
}
+static void gve_add_napi(struct gve_priv *priv, int ntfy_idx)
+{
+ struct gve_notify_block *block = &priv->ntfy_blocks[ntfy_idx];
+
+ netif_napi_add(priv->dev, &block->napi, gve_napi_poll,
+ NAPI_POLL_WEIGHT);
+}
+
+static void gve_remove_napi(struct gve_priv *priv, int ntfy_idx)
+{
+ struct gve_notify_block *block = &priv->ntfy_blocks[ntfy_idx];
+
+ netif_napi_del(&block->napi);
+}
+
+static int gve_register_qpls(struct gve_priv *priv)
+{
+ int num_qpls = gve_num_tx_qpls(priv) + gve_num_rx_qpls(priv);
+ int err;
+ int i;
+
+ for (i = 0; i < num_qpls; i++) {
+ err = gve_adminq_register_page_list(priv, &priv->qpls[i]);
+ if (err) {
+ netif_err(priv, drv, priv->dev,
+ "failed to register queue page list %d\n",
+ priv->qpls[i].id);
+ return err;
+ }
+ }
+ return 0;
+}
+
+static int gve_unregister_qpls(struct gve_priv *priv)
+{
+ int num_qpls = gve_num_tx_qpls(priv) + gve_num_rx_qpls(priv);
+ int err;
+ int i;
+
+ for (i = 0; i < num_qpls; i++) {
+ err = gve_adminq_unregister_page_list(priv, priv->qpls[i].id);
+ if (err) {
+ netif_err(priv, drv, priv->dev,
+ "Failed to unregister queue page list %d\n",
+ priv->qpls[i].id);
+ return err;
+ }
+ }
+ return 0;
+}
+
+static int gve_create_rings(struct gve_priv *priv)
+{
+ int err;
+ int i;
+
+ for (i = 0; i < priv->tx_cfg.num_queues; i++) {
+ err = gve_adminq_create_tx_queue(priv, i);
+ if (err) {
+ netif_err(priv, drv, priv->dev, "failed to create tx queue %d\n",
+ i);
+ return err;
+ }
+ netif_dbg(priv, drv, priv->dev, "created tx queue %d\n", i);
+ }
+ for (i = 0; i < priv->rx_cfg.num_queues; i++) {
+ err = gve_adminq_create_rx_queue(priv, i);
+ if (err) {
+ netif_err(priv, drv, priv->dev, "failed to create rx queue %d\n",
+ i);
+ return err;
+ }
+ /* Rx data ring has been prefilled with packet buffers at
+ * queue allocation time.
+ * Write the doorbell to provide descriptor slots and packet
+ * buffers to the NIC.
+ */
+ gve_rx_write_doorbell(priv, &priv->rx[i]);
+ netif_dbg(priv, drv, priv->dev, "created rx queue %d\n", i);
+ }
+
+ return 0;
+}
+
+static int gve_alloc_rings(struct gve_priv *priv)
+{
+ int ntfy_idx;
+ int err;
+ int i;
+
+ /* Setup tx rings */
+ priv->tx = kvzalloc(priv->tx_cfg.num_queues * sizeof(*priv->tx),
+ GFP_KERNEL);
+ if (!priv->tx)
+ return -ENOMEM;
+ err = gve_tx_alloc_rings(priv);
+ if (err)
+ goto free_tx;
+ /* Setup rx rings */
+ priv->rx = kvzalloc(priv->rx_cfg.num_queues * sizeof(*priv->rx),
+ GFP_KERNEL);
+ if (!priv->rx) {
+ err = -ENOMEM;
+ goto free_tx_queue;
+ }
+ err = gve_rx_alloc_rings(priv);
+ if (err)
+ goto free_rx;
+ /* Add tx napi & init sync stats*/
+ for (i = 0; i < priv->tx_cfg.num_queues; i++) {
+ u64_stats_init(&priv->tx[i].statss);
+ ntfy_idx = gve_tx_idx_to_ntfy(priv, i);
+ gve_add_napi(priv, ntfy_idx);
+ }
+ /* Add rx napi & init sync stats*/
+ for (i = 0; i < priv->rx_cfg.num_queues; i++) {
+ u64_stats_init(&priv->rx[i].statss);
+ ntfy_idx = gve_rx_idx_to_ntfy(priv, i);
+ gve_add_napi(priv, ntfy_idx);
+ }
+
+ return 0;
+
+free_rx:
+ kfree(priv->rx);
+ priv->rx = NULL;
+free_tx_queue:
+ gve_tx_free_rings(priv);
+free_tx:
+ kfree(priv->tx);
+ priv->tx = NULL;
+ return err;
+}
+
+static int gve_destroy_rings(struct gve_priv *priv)
+{
+ int err;
+ int i;
+
+ for (i = 0; i < priv->tx_cfg.num_queues; i++) {
+ err = gve_adminq_destroy_tx_queue(priv, i);
+ if (err) {
+ netif_err(priv, drv, priv->dev,
+ "failed to destroy tx queue %d\n",
+ i);
+ return err;
+ }
+ netif_dbg(priv, drv, priv->dev, "destroyed tx queue %d\n", i);
+ }
+ for (i = 0; i < priv->rx_cfg.num_queues; i++) {
+ err = gve_adminq_destroy_rx_queue(priv, i);
+ if (err) {
+ netif_err(priv, drv, priv->dev,
+ "failed to destroy rx queue %d\n",
+ i);
+ return err;
+ }
+ netif_dbg(priv, drv, priv->dev, "destroyed rx queue %d\n", i);
+ }
+ return 0;
+}
+
+static void gve_free_rings(struct gve_priv *priv)
+{
+ int ntfy_idx;
+ int i;
+
+ if (priv->tx) {
+ for (i = 0; i < priv->tx_cfg.num_queues; i++) {
+ ntfy_idx = gve_tx_idx_to_ntfy(priv, i);
+ gve_remove_napi(priv, ntfy_idx);
+ }
+ gve_tx_free_rings(priv);
+ kfree(priv->tx);
+ priv->tx = NULL;
+ }
+ if (priv->rx) {
+ for (i = 0; i < priv->rx_cfg.num_queues; i++) {
+ ntfy_idx = gve_rx_idx_to_ntfy(priv, i);
+ gve_remove_napi(priv, ntfy_idx);
+ }
+ gve_rx_free_rings(priv);
+ kfree(priv->rx);
+ priv->rx = NULL;
+ }
+}
+
+int gve_alloc_page(struct device *dev, struct page **page, dma_addr_t *dma,
+ enum dma_data_direction dir)
+{
+ *page = alloc_page(GFP_KERNEL);
+ if (!page)
+ return -ENOMEM;
+ *dma = dma_map_page(dev, *page, 0, PAGE_SIZE, dir);
+ if (dma_mapping_error(dev, *dma)) {
+ put_page(*page);
+ return -ENOMEM;
+ }
+ return 0;
+}
+
+static int gve_alloc_queue_page_list(struct gve_priv *priv, u32 id,
+ int pages)
+{
+ struct gve_queue_page_list *qpl = &priv->qpls[id];
+ int err;
+ int i;
+
+ if (pages + priv->num_registered_pages > priv->max_registered_pages) {
+ netif_err(priv, drv, priv->dev,
+ "Reached max number of registered pages %llu > %llu\n",
+ pages + priv->num_registered_pages,
+ priv->max_registered_pages);
+ return -EINVAL;
+ }
+
+ qpl->id = id;
+ qpl->num_entries = pages;
+ qpl->pages = kvzalloc(pages * sizeof(*qpl->pages), GFP_KERNEL);
+ /* caller handles clean up */
+ if (!qpl->pages)
+ return -ENOMEM;
+ qpl->page_buses = kvzalloc(pages * sizeof(*qpl->page_buses),
+ GFP_KERNEL);
+ /* caller handles clean up */
+ if (!qpl->page_buses)
+ return -ENOMEM;
+
+ for (i = 0; i < pages; i++) {
+ err = gve_alloc_page(&priv->pdev->dev, &qpl->pages[i],
+ &qpl->page_buses[i],
+ gve_qpl_dma_dir(priv, id));
+ /* caller handles clean up */
+ if (err)
+ return -ENOMEM;
+ }
+ priv->num_registered_pages += pages;
+
+ return 0;
+}
+
+void gve_free_page(struct device *dev, struct page *page, dma_addr_t dma,
+ enum dma_data_direction dir)
+{
+ if (!dma_mapping_error(dev, dma))
+ dma_unmap_page(dev, dma, PAGE_SIZE, dir);
+ if (page)
+ put_page(page);
+}
+
+static void gve_free_queue_page_list(struct gve_priv *priv,
+ int id)
+{
+ struct gve_queue_page_list *qpl = &priv->qpls[id];
+ int i;
+
+ if (!qpl->pages)
+ return;
+ if (!qpl->page_buses)
+ goto free_pages;
+
+ for (i = 0; i < qpl->num_entries; i++)
+ gve_free_page(&priv->pdev->dev, qpl->pages[i],
+ qpl->page_buses[i], gve_qpl_dma_dir(priv, id));
+
+ kfree(qpl->page_buses);
+free_pages:
+ kfree(qpl->pages);
+ priv->num_registered_pages -= qpl->num_entries;
+}
+
+static int gve_alloc_qpls(struct gve_priv *priv)
+{
+ int num_qpls = gve_num_tx_qpls(priv) + gve_num_rx_qpls(priv);
+ int i, j;
+ int err;
+
+ priv->qpls = kvzalloc(num_qpls * sizeof(*priv->qpls), GFP_KERNEL);
+ if (!priv->qpls)
+ return -ENOMEM;
+
+ for (i = 0; i < gve_num_tx_qpls(priv); i++) {
+ err = gve_alloc_queue_page_list(priv, i,
+ priv->tx_pages_per_qpl);
+ if (err)
+ goto free_qpls;
+ }
+ for (; i < num_qpls; i++) {
+ err = gve_alloc_queue_page_list(priv, i,
+ priv->rx_pages_per_qpl);
+ if (err)
+ goto free_qpls;
+ }
+
+ priv->qpl_cfg.qpl_map_size = BITS_TO_LONGS(num_qpls) *
+ sizeof(unsigned long) * BITS_PER_BYTE;
+ priv->qpl_cfg.qpl_id_map = kvzalloc(BITS_TO_LONGS(num_qpls) *
+ sizeof(unsigned long), GFP_KERNEL);
+ if (!priv->qpl_cfg.qpl_id_map)
+ goto free_qpls;
+
+ return 0;
+
+free_qpls:
+ for (j = 0; j <= i; j++)
+ gve_free_queue_page_list(priv, j);
+ kfree(priv->qpls);
+ return err;
+}
+
+static void gve_free_qpls(struct gve_priv *priv)
+{
+ int num_qpls = gve_num_tx_qpls(priv) + gve_num_rx_qpls(priv);
+ int i;
+
+ kfree(priv->qpl_cfg.qpl_id_map);
+
+ for (i = 0; i < num_qpls; i++)
+ gve_free_queue_page_list(priv, i);
+
+ kfree(priv->qpls);
+}
+
+static void gve_turndown(struct gve_priv *priv);
+static void gve_turnup(struct gve_priv *priv);
+
+static int gve_open(struct net_device *dev)
+{
+ struct gve_priv *priv = netdev_priv(dev);
+ int err;
+
+ err = gve_alloc_qpls(priv);
+ if (err)
+ return err;
+ err = gve_alloc_rings(priv);
+ if (err)
+ goto free_qpls;
+
+ err = netif_set_real_num_tx_queues(dev, priv->tx_cfg.num_queues);
+ if (err)
+ goto free_rings;
+ err = netif_set_real_num_rx_queues(dev, priv->rx_cfg.num_queues);
+ if (err)
+ goto free_rings;
+
+ err = gve_register_qpls(priv);
+ if (err)
+ return err;
+ err = gve_create_rings(priv);
+ if (err)
+ return err;
+ gve_set_device_rings_ok(priv);
+
+ gve_turnup(priv);
+ netif_carrier_on(dev);
+ return 0;
+
+free_rings:
+ gve_free_rings(priv);
+free_qpls:
+ gve_free_qpls(priv);
+ return err;
+}
+
+static int gve_close(struct net_device *dev)
+{
+ struct gve_priv *priv = netdev_priv(dev);
+ int err;
+
+ netif_carrier_off(dev);
+ if (gve_get_device_rings_ok(priv)) {
+ gve_turndown(priv);
+ err = gve_destroy_rings(priv);
+ if (err)
+ return err;
+ err = gve_unregister_qpls(priv);
+ if (err)
+ return err;
+ gve_clear_device_rings_ok(priv);
+ }
+
+ gve_free_rings(priv);
+ gve_free_qpls(priv);
+ return 0;
+}
+
+static void gve_turndown(struct gve_priv *priv)
+{
+ int idx;
+
+ if (netif_carrier_ok(priv->dev))
+ netif_carrier_off(priv->dev);
+
+ if (!gve_get_napi_enabled(priv))
+ return;
+
+ /* Disable napi to prevent more work from coming in */
+ for (idx = 0; idx < priv->tx_cfg.num_queues; idx++) {
+ int ntfy_idx = gve_tx_idx_to_ntfy(priv, idx);
+ struct gve_notify_block *block = &priv->ntfy_blocks[ntfy_idx];
+
+ napi_disable(&block->napi);
+ }
+ for (idx = 0; idx < priv->rx_cfg.num_queues; idx++) {
+ int ntfy_idx = gve_rx_idx_to_ntfy(priv, idx);
+ struct gve_notify_block *block = &priv->ntfy_blocks[ntfy_idx];
+
+ napi_disable(&block->napi);
+ }
+
+ /* Stop tx queues */
+ netif_tx_disable(priv->dev);
+
+ gve_clear_napi_enabled(priv);
+}
+
+static void gve_turnup(struct gve_priv *priv)
+{
+ int idx;
+
+ /* Start the tx queues */
+ netif_tx_start_all_queues(priv->dev);
+
+ /* Enable napi and unmask interrupts for all queues */
+ for (idx = 0; idx < priv->tx_cfg.num_queues; idx++) {
+ int ntfy_idx = gve_tx_idx_to_ntfy(priv, idx);
+ struct gve_notify_block *block = &priv->ntfy_blocks[ntfy_idx];
+
+ napi_enable(&block->napi);
+ iowrite32be(0, gve_irq_doorbell(priv, block));
+ }
+ for (idx = 0; idx < priv->rx_cfg.num_queues; idx++) {
+ int ntfy_idx = gve_rx_idx_to_ntfy(priv, idx);
+ struct gve_notify_block *block = &priv->ntfy_blocks[ntfy_idx];
+
+ napi_enable(&block->napi);
+ iowrite32be(0, gve_irq_doorbell(priv, block));
+ }
+
+ gve_set_napi_enabled(priv);
+}
+
+static void gve_tx_timeout(struct net_device *dev)
+{
+ struct gve_priv *priv = netdev_priv(dev);
+
+ priv->tx_timeo_cnt++;
+}
+
+static const struct net_device_ops gve_netdev_ops = {
+ .ndo_start_xmit = gve_tx,
+ .ndo_open = gve_open,
+ .ndo_stop = gve_close,
+ .ndo_get_stats64 = gve_get_stats,
+ .ndo_tx_timeout = gve_tx_timeout,
+};
+
static int gve_init_priv(struct gve_priv *priv, bool skip_describe_device)
{
int num_ntfy;
goto err;
}
+ priv->num_registered_pages = 0;
+ priv->rx_copybreak = GVE_DEFAULT_RX_COPYBREAK;
/* gvnic has one Notification Block per MSI-x vector, except for the
* management vector
*/
priv->num_ntfy_blks = (num_ntfy - 1) & ~0x1;
priv->mgmt_msix_idx = priv->num_ntfy_blks;
+ priv->tx_cfg.max_queues =
+ min_t(int, priv->tx_cfg.max_queues, priv->num_ntfy_blks / 2);
+ priv->rx_cfg.max_queues =
+ min_t(int, priv->rx_cfg.max_queues, priv->num_ntfy_blks / 2);
+
+ priv->tx_cfg.num_queues = priv->tx_cfg.max_queues;
+ priv->rx_cfg.num_queues = priv->rx_cfg.max_queues;
+ if (priv->default_num_queues > 0) {
+ priv->tx_cfg.num_queues = min_t(int, priv->default_num_queues,
+ priv->tx_cfg.num_queues);
+ priv->rx_cfg.num_queues = min_t(int, priv->default_num_queues,
+ priv->rx_cfg.num_queues);
+ }
+
+ netif_info(priv, drv, priv->dev, "TX queues %d, RX queues %d\n",
+ priv->tx_cfg.num_queues, priv->rx_cfg.num_queues);
+ netif_info(priv, drv, priv->dev, "Max TX queues %d, Max RX queues %d\n",
+ priv->tx_cfg.max_queues, priv->rx_cfg.max_queues);
+
setup_device:
err = gve_setup_device_resources(priv);
if (!err)
reg_bar = pci_iomap(pdev, GVE_REGISTER_BAR, 0);
if (!reg_bar) {
+ dev_err(&pdev->dev, "Failed to map pci bar!\n");
err = -ENOMEM;
goto abort_with_pci_region;
}
}
SET_NETDEV_DEV(dev, &pdev->dev);
pci_set_drvdata(pdev, dev);
+ dev->netdev_ops = &gve_netdev_ops;
/* advertise features */
dev->hw_features = NETIF_F_HIGHDMA;
dev->hw_features |= NETIF_F_SG;
dev->hw_features |= NETIF_F_RXCSUM;
dev->hw_features |= NETIF_F_RXHASH;
dev->features = dev->hw_features;
+ dev->watchdog_timeo = 5 * HZ;
dev->min_mtu = ETH_MIN_MTU;
netif_carrier_off(dev);
priv->reg_bar0 = reg_bar;
priv->db_bar2 = db_bar;
priv->state_flags = 0x0;
+ priv->tx_cfg.max_queues = max_tx_queues;
+ priv->rx_cfg.max_queues = max_rx_queues;
err = gve_init_priv(priv, false);
if (err)
--- /dev/null
+// SPDX-License-Identifier: (GPL-2.0 OR MIT)
+/* Google virtual Ethernet (gve) driver
+ *
+ * Copyright (C) 2015-2019 Google, Inc.
+ */
+
+#include "gve.h"
+#include "gve_adminq.h"
+#include <linux/etherdevice.h>
+
+static void gve_rx_remove_from_block(struct gve_priv *priv, int queue_idx)
+{
+ struct gve_notify_block *block =
+ &priv->ntfy_blocks[gve_rx_idx_to_ntfy(priv, queue_idx)];
+
+ block->rx = NULL;
+}
+
+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;
+ size_t bytes;
+ u32 slots;
+
+ gve_rx_remove_from_block(priv, idx);
+
+ bytes = sizeof(struct gve_rx_desc) * priv->rx_desc_cnt;
+ dma_free_coherent(dev, bytes, rx->desc.desc_ring, rx->desc.bus);
+ rx->desc.desc_ring = NULL;
+
+ dma_free_coherent(dev, sizeof(*rx->q_resources),
+ rx->q_resources, rx->q_resources_bus);
+ rx->q_resources = NULL;
+
+ gve_unassign_qpl(priv, rx->data.qpl->id);
+ rx->data.qpl = NULL;
+ kfree(rx->data.page_info);
+
+ slots = rx->data.mask + 1;
+ bytes = sizeof(*rx->data.data_ring) * slots;
+ dma_free_coherent(dev, bytes, rx->data.data_ring,
+ rx->data.data_bus);
+ rx->data.data_ring = NULL;
+ netif_dbg(priv, drv, priv->dev, "freed rx ring %d\n", idx);
+}
+
+static void gve_setup_rx_buffer(struct gve_rx_slot_page_info *page_info,
+ struct gve_rx_data_slot *slot,
+ dma_addr_t addr, struct page *page)
+{
+ page_info->page = page;
+ page_info->page_offset = 0;
+ page_info->page_address = page_address(page);
+ slot->qpl_offset = cpu_to_be64(addr);
+}
+
+static int gve_prefill_rx_pages(struct gve_rx_ring *rx)
+{
+ struct gve_priv *priv = rx->gve;
+ u32 slots;
+ int i;
+
+ /* Allocate one page per Rx queue slot. Each page is split into two
+ * packet buffers, when possible we "page flip" between the two.
+ */
+ slots = rx->data.mask + 1;
+
+ rx->data.page_info = kvzalloc(slots *
+ sizeof(*rx->data.page_info), GFP_KERNEL);
+ if (!rx->data.page_info)
+ return -ENOMEM;
+
+ 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;
+
+ gve_setup_rx_buffer(&rx->data.page_info[i],
+ &rx->data.data_ring[i], addr, page);
+ }
+
+ return slots;
+}
+
+static void gve_rx_add_to_block(struct gve_priv *priv, int queue_idx)
+{
+ u32 ntfy_idx = gve_rx_idx_to_ntfy(priv, queue_idx);
+ struct gve_notify_block *block = &priv->ntfy_blocks[ntfy_idx];
+ struct gve_rx_ring *rx = &priv->rx[queue_idx];
+
+ block->rx = rx;
+ rx->ntfy_id = ntfy_idx;
+}
+
+static int gve_rx_alloc_ring(struct gve_priv *priv, int idx)
+{
+ struct gve_rx_ring *rx = &priv->rx[idx];
+ struct device *hdev = &priv->pdev->dev;
+ u32 slots, npages;
+ int filled_pages;
+ size_t bytes;
+ int err;
+
+ netif_dbg(priv, drv, priv->dev, "allocating rx ring\n");
+ /* Make sure everything is zeroed to start with */
+ memset(rx, 0, sizeof(*rx));
+
+ rx->gve = priv;
+ rx->q_num = idx;
+
+ slots = priv->rx_pages_per_qpl;
+ rx->data.mask = slots - 1;
+
+ /* alloc rx data ring */
+ bytes = sizeof(*rx->data.data_ring) * slots;
+ rx->data.data_ring = dma_alloc_coherent(hdev, bytes,
+ &rx->data.data_bus,
+ GFP_KERNEL);
+ if (!rx->data.data_ring)
+ return -ENOMEM;
+ filled_pages = gve_prefill_rx_pages(rx);
+ if (filled_pages < 0) {
+ err = -ENOMEM;
+ goto abort_with_slots;
+ }
+ rx->desc.fill_cnt = filled_pages;
+ /* Ensure data ring slots (packet buffers) are visible. */
+ dma_wmb();
+
+ /* Alloc gve_queue_resources */
+ rx->q_resources =
+ dma_alloc_coherent(hdev,
+ sizeof(*rx->q_resources),
+ &rx->q_resources_bus,
+ GFP_KERNEL);
+ if (!rx->q_resources) {
+ err = -ENOMEM;
+ goto abort_filled;
+ }
+ netif_dbg(priv, drv, priv->dev, "rx[%d]->data.data_bus=%lx\n", idx,
+ (unsigned long)rx->data.data_bus);
+
+ /* alloc rx desc ring */
+ bytes = sizeof(struct gve_rx_desc) * priv->rx_desc_cnt;
+ npages = bytes / PAGE_SIZE;
+ if (npages * PAGE_SIZE != bytes) {
+ err = -EIO;
+ goto abort_with_q_resources;
+ }
+
+ rx->desc.desc_ring = dma_alloc_coherent(hdev, bytes, &rx->desc.bus,
+ GFP_KERNEL);
+ if (!rx->desc.desc_ring) {
+ err = -ENOMEM;
+ goto abort_with_q_resources;
+ }
+ rx->desc.mask = slots - 1;
+ rx->desc.cnt = 0;
+ rx->desc.seqno = 1;
+ gve_rx_add_to_block(priv, idx);
+
+ return 0;
+
+abort_with_q_resources:
+ dma_free_coherent(hdev, sizeof(*rx->q_resources),
+ rx->q_resources, rx->q_resources_bus);
+ rx->q_resources = NULL;
+abort_filled:
+ kfree(rx->data.page_info);
+abort_with_slots:
+ bytes = sizeof(*rx->data.data_ring) * slots;
+ dma_free_coherent(hdev, bytes, rx->data.data_ring, rx->data.data_bus);
+ rx->data.data_ring = NULL;
+
+ return err;
+}
+
+int gve_rx_alloc_rings(struct gve_priv *priv)
+{
+ int err = 0;
+ int i;
+
+ for (i = 0; i < priv->rx_cfg.num_queues; i++) {
+ err = gve_rx_alloc_ring(priv, i);
+ if (err) {
+ netif_err(priv, drv, priv->dev,
+ "Failed to alloc rx ring=%d: err=%d\n",
+ i, err);
+ break;
+ }
+ }
+ /* Unallocate if there was an error */
+ if (err) {
+ int j;
+
+ for (j = 0; j < i; j++)
+ gve_rx_free_ring(priv, j);
+ }
+ return err;
+}
+
+void gve_rx_free_rings(struct gve_priv *priv)
+{
+ int i;
+
+ for (i = 0; i < priv->rx_cfg.num_queues; i++)
+ gve_rx_free_ring(priv, i);
+}
+
+void gve_rx_write_doorbell(struct gve_priv *priv, struct gve_rx_ring *rx)
+{
+ u32 db_idx = be32_to_cpu(rx->q_resources->db_index);
+
+ iowrite32be(rx->desc.fill_cnt, &priv->db_bar2[db_idx]);
+}
+
+static enum pkt_hash_types gve_rss_type(__be16 pkt_flags)
+{
+ if (likely(pkt_flags & (GVE_RXF_TCP | GVE_RXF_UDP)))
+ return PKT_HASH_TYPE_L4;
+ if (pkt_flags & (GVE_RXF_IPV4 | GVE_RXF_IPV6))
+ return PKT_HASH_TYPE_L3;
+ return PKT_HASH_TYPE_L2;
+}
+
+static struct sk_buff *gve_rx_copy(struct net_device *dev,
+ struct napi_struct *napi,
+ struct gve_rx_slot_page_info *page_info,
+ u16 len)
+{
+ struct sk_buff *skb = napi_alloc_skb(napi, len);
+ void *va = page_info->page_address + GVE_RX_PAD +
+ page_info->page_offset;
+
+ if (unlikely(!skb))
+ return NULL;
+
+ __skb_put(skb, len);
+
+ skb_copy_to_linear_data(skb, va, len);
+
+ skb->protocol = eth_type_trans(skb, dev);
+ return skb;
+}
+
+static struct sk_buff *gve_rx_add_frags(struct net_device *dev,
+ struct napi_struct *napi,
+ struct gve_rx_slot_page_info *page_info,
+ u16 len)
+{
+ struct sk_buff *skb = napi_get_frags(napi);
+
+ if (unlikely(!skb))
+ return NULL;
+
+ skb_add_rx_frag(skb, 0, page_info->page,
+ page_info->page_offset +
+ GVE_RX_PAD, len, PAGE_SIZE / 2);
+
+ return skb;
+}
+
+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);
+
+ page_info->page_offset ^= PAGE_SIZE / 2;
+ addr ^= PAGE_SIZE / 2;
+ data_ring->qpl_offset = cpu_to_be64(addr);
+}
+
+static bool gve_rx(struct gve_rx_ring *rx, struct gve_rx_desc *rx_desc,
+ netdev_features_t feat)
+{
+ struct gve_rx_slot_page_info *page_info;
+ 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;
+ int pagecount;
+ u16 len;
+ u32 idx;
+
+ /* drop this packet */
+ if (unlikely(rx_desc->flags_seq & GVE_RXF_ERR))
+ return true;
+
+ len = be16_to_cpu(rx_desc->len) - GVE_RX_PAD;
+ idx = rx->data.cnt & rx->data.mask;
+ page_info = &rx->data.page_info[idx];
+
+ /* 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.
+ */
+
+#if PAGE_SIZE == 4096
+ if (len <= priv->rx_copybreak) {
+ /* Just copy small packets */
+ skb = gve_rx_copy(dev, napi, page_info, len);
+ goto have_skb;
+ }
+ if (unlikely(!gve_can_recycle_pages(dev))) {
+ skb = gve_rx_copy(dev, napi, page_info, len);
+ goto have_skb;
+ }
+ pagecount = page_count(page_info->page);
+ if (pagecount == 1) {
+ /* No part of this page is used by any SKBs; we attach
+ * the page fragment to a new SKB and pass it up the
+ * stack.
+ */
+ skb = gve_rx_add_frags(dev, napi, page_info, len);
+ if (!skb)
+ return true;
+ /* Make sure the kernel stack can't release the page */
+ get_page(page_info->page);
+ /* "flip" to other packet buffer on this page */
+ gve_rx_flip_buff(page_info, &rx->data.data_ring[idx]);
+ } else if (pagecount >= 2) {
+ /* We have previously passed the other half of this
+ * page up the stack, but it has not yet been freed.
+ */
+ skb = gve_rx_copy(dev, napi, page_info, len);
+ } else {
+ WARN(pagecount < 1, "Pagecount should never be < 1");
+ return false;
+ }
+#else
+ skb = gve_rx_copy(dev, napi, page_info, len);
+#endif
+
+have_skb:
+ if (!skb)
+ return true;
+
+ rx->data.cnt++;
+
+ if (likely(feat & NETIF_F_RXCSUM)) {
+ /* NIC passes up the partial sum */
+ if (rx_desc->csum)
+ skb->ip_summed = CHECKSUM_COMPLETE;
+ else
+ skb->ip_summed = CHECKSUM_NONE;
+ skb->csum = csum_unfold(rx_desc->csum);
+ }
+
+ /* parse flags & pass relevant info up */
+ if (likely(feat & NETIF_F_RXHASH) &&
+ gve_needs_rss(rx_desc->flags_seq))
+ skb_set_hash(skb, be32_to_cpu(rx_desc->rss_hash),
+ gve_rss_type(rx_desc->flags_seq));
+
+ if (skb_is_nonlinear(skb))
+ napi_gro_frags(napi);
+ else
+ napi_gro_receive(napi, skb);
+ return true;
+}
+
+static bool gve_rx_work_pending(struct gve_rx_ring *rx)
+{
+ struct gve_rx_desc *desc;
+ __be16 flags_seq;
+ u32 next_idx;
+
+ next_idx = rx->desc.cnt & rx->desc.mask;
+ desc = rx->desc.desc_ring + next_idx;
+
+ flags_seq = desc->flags_seq;
+ /* Make sure we have synchronized the seq no with the device */
+ smp_rmb();
+
+ return (GVE_SEQNO(flags_seq) == rx->desc.seqno);
+}
+
+bool gve_clean_rx_done(struct gve_rx_ring *rx, int budget,
+ netdev_features_t feat)
+{
+ struct gve_priv *priv = rx->gve;
+ struct gve_rx_desc *desc;
+ u32 cnt = rx->desc.cnt;
+ u32 idx = cnt & rx->desc.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) {
+ 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);
+ netif_info(priv, rx_status, priv->dev,
+ "[%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))
+ return false;
+ cnt++;
+ idx = cnt & rx->desc.mask;
+ desc = rx->desc.desc_ring + idx;
+ rx->desc.seqno = gve_next_seqno(rx->desc.seqno);
+ work_done++;
+ }
+
+ if (!work_done)
+ return false;
+
+ u64_stats_update_begin(&rx->statss);
+ rx->rpackets += work_done;
+ rx->rbytes += bytes;
+ u64_stats_update_end(&rx->statss);
+ rx->desc.cnt = cnt;
+ rx->desc.fill_cnt += work_done;
+
+ /* restock desc ring slots */
+ dma_wmb(); /* Ensure descs are visible before ringing doorbell */
+ gve_rx_write_doorbell(priv, rx);
+ return gve_rx_work_pending(rx);
+}
+
+bool gve_rx_poll(struct gve_notify_block *block, int budget)
+{
+ struct gve_rx_ring *rx = block->rx;
+ netdev_features_t feat;
+ bool repoll = false;
+
+ feat = block->napi.dev->features;
+
+ /* If budget is 0, do all the work */
+ if (budget == 0)
+ budget = INT_MAX;
+
+ if (budget > 0)
+ repoll |= gve_clean_rx_done(rx, budget, feat);
+ else
+ repoll |= gve_rx_work_pending(rx);
+ return repoll;
+}
--- /dev/null
+// SPDX-License-Identifier: (GPL-2.0 OR MIT)
+/* Google virtual Ethernet (gve) driver
+ *
+ * Copyright (C) 2015-2019 Google, Inc.
+ */
+
+#include "gve.h"
+#include "gve_adminq.h"
+#include <linux/ip.h>
+#include <linux/tcp.h>
+#include <linux/vmalloc.h>
+#include <linux/skbuff.h>
+
+static inline void gve_tx_put_doorbell(struct gve_priv *priv,
+ struct gve_queue_resources *q_resources,
+ u32 val)
+{
+ iowrite32be(val, &priv->db_bar2[be32_to_cpu(q_resources->db_index)]);
+}
+
+/* gvnic can only transmit from a Registered Segment.
+ * We copy skb payloads into the registered segment before writing Tx
+ * descriptors and ringing the Tx doorbell.
+ *
+ * gve_tx_fifo_* manages the Registered Segment as a FIFO - clients must
+ * free allocations in the order they were allocated.
+ */
+
+static int gve_tx_fifo_init(struct gve_priv *priv, struct gve_tx_fifo *fifo)
+{
+ fifo->base = vmap(fifo->qpl->pages, fifo->qpl->num_entries, VM_MAP,
+ PAGE_KERNEL);
+ if (unlikely(!fifo->base)) {
+ netif_err(priv, drv, priv->dev, "Failed to vmap fifo, qpl_id = %d\n",
+ fifo->qpl->id);
+ return -ENOMEM;
+ }
+
+ fifo->size = fifo->qpl->num_entries * PAGE_SIZE;
+ atomic_set(&fifo->available, fifo->size);
+ fifo->head = 0;
+ return 0;
+}
+
+static void gve_tx_fifo_release(struct gve_priv *priv, struct gve_tx_fifo *fifo)
+{
+ WARN(atomic_read(&fifo->available) != fifo->size,
+ "Releasing non-empty fifo");
+
+ vunmap(fifo->base);
+}
+
+static int gve_tx_fifo_pad_alloc_one_frag(struct gve_tx_fifo *fifo,
+ size_t bytes)
+{
+ return (fifo->head + bytes < fifo->size) ? 0 : fifo->size - fifo->head;
+}
+
+static bool gve_tx_fifo_can_alloc(struct gve_tx_fifo *fifo, size_t bytes)
+{
+ return (atomic_read(&fifo->available) <= bytes) ? false : true;
+}
+
+/* gve_tx_alloc_fifo - Allocate fragment(s) from Tx FIFO
+ * @fifo: FIFO to allocate from
+ * @bytes: Allocation size
+ * @iov: Scatter-gather elements to fill with allocation fragment base/len
+ *
+ * Returns number of valid elements in iov[] or negative on error.
+ *
+ * Allocations from a given FIFO must be externally synchronized but concurrent
+ * allocation and frees are allowed.
+ */
+static int gve_tx_alloc_fifo(struct gve_tx_fifo *fifo, size_t bytes,
+ struct gve_tx_iovec iov[2])
+{
+ size_t overflow, padding;
+ u32 aligned_head;
+ int nfrags = 0;
+
+ if (!bytes)
+ return 0;
+
+ /* This check happens before we know how much padding is needed to
+ * align to a cacheline boundary for the payload, but that is fine,
+ * because the FIFO head always start aligned, and the FIFO's boundaries
+ * are aligned, so if there is space for the data, there is space for
+ * the padding to the next alignment.
+ */
+ WARN(!gve_tx_fifo_can_alloc(fifo, bytes),
+ "Reached %s when there's not enough space in the fifo", __func__);
+
+ nfrags++;
+
+ iov[0].iov_offset = fifo->head;
+ iov[0].iov_len = bytes;
+ fifo->head += bytes;
+
+ if (fifo->head > fifo->size) {
+ /* If the allocation did not fit in the tail fragment of the
+ * FIFO, also use the head fragment.
+ */
+ nfrags++;
+ overflow = fifo->head - fifo->size;
+ iov[0].iov_len -= overflow;
+ iov[1].iov_offset = 0; /* Start of fifo*/
+ iov[1].iov_len = overflow;
+
+ fifo->head = overflow;
+ }
+
+ /* Re-align to a cacheline boundary */
+ aligned_head = L1_CACHE_ALIGN(fifo->head);
+ padding = aligned_head - fifo->head;
+ iov[nfrags - 1].iov_padding = padding;
+ atomic_sub(bytes + padding, &fifo->available);
+ fifo->head = aligned_head;
+
+ if (fifo->head == fifo->size)
+ fifo->head = 0;
+
+ return nfrags;
+}
+
+/* gve_tx_free_fifo - Return space to Tx FIFO
+ * @fifo: FIFO to return fragments to
+ * @bytes: Bytes to free
+ */
+static void gve_tx_free_fifo(struct gve_tx_fifo *fifo, size_t bytes)
+{
+ atomic_add(bytes, &fifo->available);
+}
+
+static void gve_tx_remove_from_block(struct gve_priv *priv, int queue_idx)
+{
+ struct gve_notify_block *block =
+ &priv->ntfy_blocks[gve_tx_idx_to_ntfy(priv, queue_idx)];
+
+ block->tx = NULL;
+}
+
+static int gve_clean_tx_done(struct gve_priv *priv, struct gve_tx_ring *tx,
+ u32 to_do, bool try_to_wake);
+
+static void gve_tx_free_ring(struct gve_priv *priv, int idx)
+{
+ struct gve_tx_ring *tx = &priv->tx[idx];
+ struct device *hdev = &priv->pdev->dev;
+ size_t bytes;
+ u32 slots;
+
+ gve_tx_remove_from_block(priv, idx);
+ slots = tx->mask + 1;
+ gve_clean_tx_done(priv, tx, tx->req, false);
+ netdev_tx_reset_queue(tx->netdev_txq);
+
+ dma_free_coherent(hdev, sizeof(*tx->q_resources),
+ tx->q_resources, tx->q_resources_bus);
+ tx->q_resources = NULL;
+
+ gve_tx_fifo_release(priv, &tx->tx_fifo);
+ gve_unassign_qpl(priv, tx->tx_fifo.qpl->id);
+ tx->tx_fifo.qpl = NULL;
+
+ bytes = sizeof(*tx->desc) * slots;
+ dma_free_coherent(hdev, bytes, tx->desc, tx->bus);
+ tx->desc = NULL;
+
+ vfree(tx->info);
+ tx->info = NULL;
+
+ netif_dbg(priv, drv, priv->dev, "freed tx queue %d\n", idx);
+}
+
+static void gve_tx_add_to_block(struct gve_priv *priv, int queue_idx)
+{
+ int ntfy_idx = gve_tx_idx_to_ntfy(priv, queue_idx);
+ struct gve_notify_block *block = &priv->ntfy_blocks[ntfy_idx];
+ struct gve_tx_ring *tx = &priv->tx[queue_idx];
+
+ block->tx = tx;
+ tx->ntfy_id = ntfy_idx;
+}
+
+static int gve_tx_alloc_ring(struct gve_priv *priv, int idx)
+{
+ struct gve_tx_ring *tx = &priv->tx[idx];
+ struct device *hdev = &priv->pdev->dev;
+ u32 slots = priv->tx_desc_cnt;
+ size_t bytes;
+
+ /* Make sure everything is zeroed to start */
+ memset(tx, 0, sizeof(*tx));
+ tx->q_num = idx;
+
+ tx->mask = slots - 1;
+
+ /* alloc metadata */
+ tx->info = vzalloc(sizeof(*tx->info) * slots);
+ if (!tx->info)
+ return -ENOMEM;
+
+ /* alloc tx queue */
+ bytes = sizeof(*tx->desc) * slots;
+ tx->desc = dma_alloc_coherent(hdev, bytes, &tx->bus, GFP_KERNEL);
+ if (!tx->desc)
+ goto abort_with_info;
+
+ tx->tx_fifo.qpl = gve_assign_tx_qpl(priv);
+
+ /* map Tx FIFO */
+ if (gve_tx_fifo_init(priv, &tx->tx_fifo))
+ goto abort_with_desc;
+
+ tx->q_resources =
+ dma_alloc_coherent(hdev,
+ sizeof(*tx->q_resources),
+ &tx->q_resources_bus,
+ GFP_KERNEL);
+ if (!tx->q_resources)
+ goto abort_with_fifo;
+
+ netif_dbg(priv, drv, priv->dev, "tx[%d]->bus=%lx\n", idx,
+ (unsigned long)tx->bus);
+ tx->netdev_txq = netdev_get_tx_queue(priv->dev, idx);
+ gve_tx_add_to_block(priv, idx);
+
+ return 0;
+
+abort_with_fifo:
+ gve_tx_fifo_release(priv, &tx->tx_fifo);
+abort_with_desc:
+ dma_free_coherent(hdev, bytes, tx->desc, tx->bus);
+ tx->desc = NULL;
+abort_with_info:
+ vfree(tx->info);
+ tx->info = NULL;
+ return -ENOMEM;
+}
+
+int gve_tx_alloc_rings(struct gve_priv *priv)
+{
+ int err = 0;
+ int i;
+
+ for (i = 0; i < priv->tx_cfg.num_queues; i++) {
+ err = gve_tx_alloc_ring(priv, i);
+ if (err) {
+ netif_err(priv, drv, priv->dev,
+ "Failed to alloc tx ring=%d: err=%d\n",
+ i, err);
+ break;
+ }
+ }
+ /* Unallocate if there was an error */
+ if (err) {
+ int j;
+
+ for (j = 0; j < i; j++)
+ gve_tx_free_ring(priv, j);
+ }
+ return err;
+}
+
+void gve_tx_free_rings(struct gve_priv *priv)
+{
+ int i;
+
+ for (i = 0; i < priv->tx_cfg.num_queues; i++)
+ gve_tx_free_ring(priv, i);
+}
+
+/* gve_tx_avail - Calculates the number of slots available in the ring
+ * @tx: tx ring to check
+ *
+ * Returns the number of slots available
+ *
+ * The capacity of the queue is mask + 1. We don't need to reserve an entry.
+ **/
+static inline u32 gve_tx_avail(struct gve_tx_ring *tx)
+{
+ return tx->mask + 1 - (tx->req - tx->done);
+}
+
+static inline int gve_skb_fifo_bytes_required(struct gve_tx_ring *tx,
+ struct sk_buff *skb)
+{
+ int pad_bytes, align_hdr_pad;
+ int bytes;
+ int hlen;
+
+ hlen = skb_is_gso(skb) ? skb_checksum_start_offset(skb) +
+ tcp_hdrlen(skb) : skb_headlen(skb);
+
+ pad_bytes = gve_tx_fifo_pad_alloc_one_frag(&tx->tx_fifo,
+ hlen);
+ /* We need to take into account the header alignment padding. */
+ align_hdr_pad = L1_CACHE_ALIGN(hlen) - hlen;
+ bytes = align_hdr_pad + pad_bytes + skb->len;
+
+ return bytes;
+}
+
+/* The most descriptors we could need are 3 - 1 for the headers, 1 for
+ * the beginning of the payload at the end of the FIFO, and 1 if the
+ * payload wraps to the beginning of the FIFO.
+ */
+#define MAX_TX_DESC_NEEDED 3
+
+/* Check if sufficient resources (descriptor ring space, FIFO space) are
+ * available to transmit the given number of bytes.
+ */
+static inline bool gve_can_tx(struct gve_tx_ring *tx, int bytes_required)
+{
+ return (gve_tx_avail(tx) >= MAX_TX_DESC_NEEDED &&
+ gve_tx_fifo_can_alloc(&tx->tx_fifo, bytes_required));
+}
+
+/* Stops the queue if the skb cannot be transmitted. */
+static int gve_maybe_stop_tx(struct gve_tx_ring *tx, struct sk_buff *skb)
+{
+ int bytes_required;
+
+ bytes_required = gve_skb_fifo_bytes_required(tx, skb);
+ if (likely(gve_can_tx(tx, bytes_required)))
+ return 0;
+
+ /* No space, so stop the queue */
+ tx->stop_queue++;
+ netif_tx_stop_queue(tx->netdev_txq);
+ smp_mb(); /* sync with restarting queue in gve_clean_tx_done() */
+
+ /* Now check for resources again, in case gve_clean_tx_done() freed
+ * resources after we checked and we stopped the queue after
+ * gve_clean_tx_done() checked.
+ *
+ * gve_maybe_stop_tx() gve_clean_tx_done()
+ * nsegs/can_alloc test failed
+ * gve_tx_free_fifo()
+ * if (tx queue stopped)
+ * netif_tx_queue_wake()
+ * netif_tx_stop_queue()
+ * Need to check again for space here!
+ */
+ if (likely(!gve_can_tx(tx, bytes_required)))
+ return -EBUSY;
+
+ netif_tx_start_queue(tx->netdev_txq);
+ tx->wake_queue++;
+ return 0;
+}
+
+static void gve_tx_fill_pkt_desc(union gve_tx_desc *pkt_desc,
+ struct sk_buff *skb, bool is_gso,
+ int l4_hdr_offset, u32 desc_cnt,
+ u16 hlen, u64 addr)
+{
+ /* l4_hdr_offset and csum_offset are in units of 16-bit words */
+ if (is_gso) {
+ pkt_desc->pkt.type_flags = GVE_TXD_TSO | GVE_TXF_L4CSUM;
+ pkt_desc->pkt.l4_csum_offset = skb->csum_offset >> 1;
+ pkt_desc->pkt.l4_hdr_offset = l4_hdr_offset >> 1;
+ } else if (likely(skb->ip_summed == CHECKSUM_PARTIAL)) {
+ pkt_desc->pkt.type_flags = GVE_TXD_STD | GVE_TXF_L4CSUM;
+ pkt_desc->pkt.l4_csum_offset = skb->csum_offset >> 1;
+ pkt_desc->pkt.l4_hdr_offset = l4_hdr_offset >> 1;
+ } else {
+ pkt_desc->pkt.type_flags = GVE_TXD_STD;
+ pkt_desc->pkt.l4_csum_offset = 0;
+ pkt_desc->pkt.l4_hdr_offset = 0;
+ }
+ pkt_desc->pkt.desc_cnt = desc_cnt;
+ pkt_desc->pkt.len = cpu_to_be16(skb->len);
+ pkt_desc->pkt.seg_len = cpu_to_be16(hlen);
+ pkt_desc->pkt.seg_addr = cpu_to_be64(addr);
+}
+
+static void gve_tx_fill_seg_desc(union gve_tx_desc *seg_desc,
+ struct sk_buff *skb, bool is_gso,
+ u16 len, u64 addr)
+{
+ seg_desc->seg.type_flags = GVE_TXD_SEG;
+ if (is_gso) {
+ if (skb_is_gso_v6(skb))
+ seg_desc->seg.type_flags |= GVE_TXSF_IPV6;
+ seg_desc->seg.l3_offset = skb_network_offset(skb) >> 1;
+ seg_desc->seg.mss = cpu_to_be16(skb_shinfo(skb)->gso_size);
+ }
+ seg_desc->seg.seg_len = cpu_to_be16(len);
+ seg_desc->seg.seg_addr = cpu_to_be64(addr);
+}
+
+static int gve_tx_add_skb(struct gve_tx_ring *tx, struct sk_buff *skb)
+{
+ int pad_bytes, hlen, hdr_nfrags, payload_nfrags, l4_hdr_offset;
+ union gve_tx_desc *pkt_desc, *seg_desc;
+ struct gve_tx_buffer_state *info;
+ bool is_gso = skb_is_gso(skb);
+ u32 idx = tx->req & tx->mask;
+ int payload_iov = 2;
+ int copy_offset;
+ u32 next_idx;
+ int i;
+
+ info = &tx->info[idx];
+ pkt_desc = &tx->desc[idx];
+
+ l4_hdr_offset = skb_checksum_start_offset(skb);
+ /* If the skb is gso, then we want the tcp header in the first segment
+ * otherwise we want the linear portion of the skb (which will contain
+ * the checksum because skb->csum_start and skb->csum_offset are given
+ * relative to skb->head) in the first segment.
+ */
+ hlen = is_gso ? l4_hdr_offset + tcp_hdrlen(skb) :
+ skb_headlen(skb);
+
+ info->skb = skb;
+ /* We don't want to split the header, so if necessary, pad to the end
+ * of the fifo and then put the header at the beginning of the fifo.
+ */
+ pad_bytes = gve_tx_fifo_pad_alloc_one_frag(&tx->tx_fifo, hlen);
+ hdr_nfrags = gve_tx_alloc_fifo(&tx->tx_fifo, hlen + pad_bytes,
+ &info->iov[0]);
+ WARN(!hdr_nfrags, "hdr_nfrags should never be 0!");
+ payload_nfrags = gve_tx_alloc_fifo(&tx->tx_fifo, skb->len - hlen,
+ &info->iov[payload_iov]);
+
+ gve_tx_fill_pkt_desc(pkt_desc, skb, is_gso, l4_hdr_offset,
+ 1 + payload_nfrags, hlen,
+ info->iov[hdr_nfrags - 1].iov_offset);
+
+ skb_copy_bits(skb, 0,
+ tx->tx_fifo.base + info->iov[hdr_nfrags - 1].iov_offset,
+ hlen);
+ copy_offset = hlen;
+
+ for (i = payload_iov; i < payload_nfrags + payload_iov; i++) {
+ next_idx = (tx->req + 1 + i - payload_iov) & tx->mask;
+ seg_desc = &tx->desc[next_idx];
+
+ gve_tx_fill_seg_desc(seg_desc, skb, is_gso,
+ info->iov[i].iov_len,
+ info->iov[i].iov_offset);
+
+ skb_copy_bits(skb, copy_offset,
+ tx->tx_fifo.base + info->iov[i].iov_offset,
+ info->iov[i].iov_len);
+ copy_offset += info->iov[i].iov_len;
+ }
+
+ return 1 + payload_nfrags;
+}
+
+netdev_tx_t gve_tx(struct sk_buff *skb, struct net_device *dev)
+{
+ struct gve_priv *priv = netdev_priv(dev);
+ struct gve_tx_ring *tx;
+ int nsegs;
+
+ WARN(skb_get_queue_mapping(skb) > priv->tx_cfg.num_queues,
+ "skb queue index out of range");
+ tx = &priv->tx[skb_get_queue_mapping(skb)];
+ if (unlikely(gve_maybe_stop_tx(tx, skb))) {
+ /* We need to ring the txq doorbell -- we have stopped the Tx
+ * queue for want of resources, but prior calls to gve_tx()
+ * may have added descriptors without ringing the doorbell.
+ */
+
+ /* Ensure tx descs from a prior gve_tx are visible before
+ * ringing doorbell.
+ */
+ dma_wmb();
+ gve_tx_put_doorbell(priv, tx->q_resources, tx->req);
+ return NETDEV_TX_BUSY;
+ }
+ nsegs = gve_tx_add_skb(tx, skb);
+
+ netdev_tx_sent_queue(tx->netdev_txq, skb->len);
+ skb_tx_timestamp(skb);
+
+ /* give packets to NIC */
+ tx->req += nsegs;
+
+ if (!netif_xmit_stopped(tx->netdev_txq) && netdev_xmit_more())
+ return NETDEV_TX_OK;
+
+ /* Ensure tx descs are visible before ringing doorbell */
+ dma_wmb();
+ gve_tx_put_doorbell(priv, tx->q_resources, tx->req);
+ return NETDEV_TX_OK;
+}
+
+#define GVE_TX_START_THRESH PAGE_SIZE
+
+static int gve_clean_tx_done(struct gve_priv *priv, struct gve_tx_ring *tx,
+ u32 to_do, bool try_to_wake)
+{
+ struct gve_tx_buffer_state *info;
+ u64 pkts = 0, bytes = 0;
+ size_t space_freed = 0;
+ struct sk_buff *skb;
+ int i, j;
+ u32 idx;
+
+ for (j = 0; j < to_do; j++) {
+ idx = tx->done & tx->mask;
+ netif_info(priv, tx_done, priv->dev,
+ "[%d] %s: idx=%d (req=%u done=%u)\n",
+ tx->q_num, __func__, idx, tx->req, tx->done);
+ info = &tx->info[idx];
+ skb = info->skb;
+
+ /* Mark as free */
+ if (skb) {
+ info->skb = NULL;
+ bytes += skb->len;
+ pkts++;
+ dev_consume_skb_any(skb);
+ /* FIFO free */
+ for (i = 0; i < ARRAY_SIZE(info->iov); i++) {
+ space_freed += info->iov[i].iov_len +
+ info->iov[i].iov_padding;
+ info->iov[i].iov_len = 0;
+ info->iov[i].iov_padding = 0;
+ }
+ }
+ tx->done++;
+ }
+
+ gve_tx_free_fifo(&tx->tx_fifo, space_freed);
+ u64_stats_update_begin(&tx->statss);
+ tx->bytes_done += bytes;
+ tx->pkt_done += pkts;
+ u64_stats_update_end(&tx->statss);
+ netdev_tx_completed_queue(tx->netdev_txq, pkts, bytes);
+
+ /* start the queue if we've stopped it */
+#ifndef CONFIG_BQL
+ /* Make sure that the doorbells are synced */
+ smp_mb();
+#endif
+ if (try_to_wake && netif_tx_queue_stopped(tx->netdev_txq) &&
+ likely(gve_can_tx(tx, GVE_TX_START_THRESH))) {
+ tx->wake_queue++;
+ netif_tx_wake_queue(tx->netdev_txq);
+ }
+
+ return pkts;
+}
+
+__be32 gve_tx_load_event_counter(struct gve_priv *priv,
+ struct gve_tx_ring *tx)
+{
+ u32 counter_index = be32_to_cpu((tx->q_resources->counter_index));
+
+ return READ_ONCE(priv->counter_array[counter_index]);
+}
+
+bool gve_tx_poll(struct gve_notify_block *block, int budget)
+{
+ struct gve_priv *priv = block->priv;
+ struct gve_tx_ring *tx = block->tx;
+ bool repoll = false;
+ u32 nic_done;
+ u32 to_do;
+
+ /* If budget is 0, do all the work */
+ if (budget == 0)
+ budget = INT_MAX;
+
+ /* Find out how much work there is to be done */
+ tx->last_nic_done = gve_tx_load_event_counter(priv, tx);
+ nic_done = be32_to_cpu(tx->last_nic_done);
+ if (budget > 0) {
+ /* Do as much work as we have that the budget will
+ * allow
+ */
+ to_do = min_t(u32, (nic_done - tx->done), budget);
+ gve_clean_tx_done(priv, tx, to_do, true);
+ }
+ /* If we still have work we want to repoll */
+ repoll |= (nic_done != tx->done);
+ return repoll;
+}
projects / platform / kernel / linux-rpi.git / commitdiff