diff --git a/drivers/net/ethernet/cisco/enic/enic.h b/drivers/net/ethernet/cisco/enic/enic.h index 398227448b37..0f08de228b36 100644 --- a/drivers/net/ethernet/cisco/enic/enic.h +++ b/drivers/net/ethernet/cisco/enic/enic.h @@ -301,6 +301,14 @@ struct enic { struct vnic_rq admin_rq; struct vnic_cq admin_cq[2]; struct vnic_intr admin_intr; + struct delayed_work admin_poll_work; + unsigned int admin_intr_index; + struct work_struct admin_msg_work; + spinlock_t admin_msg_lock; /* protects admin_msg_list */ + struct list_head admin_msg_list; + unsigned int admin_msg_count; /* current depth of admin_msg_list */ + void (*admin_rq_handler)(struct enic *enic, void *buf, + unsigned int len); }; static inline struct net_device *vnic_get_netdev(struct vnic_dev *vdev) diff --git a/drivers/net/ethernet/cisco/enic/enic_admin.c b/drivers/net/ethernet/cisco/enic/enic_admin.c index edd0a2d3994b..65aec9651a6f 100644 --- a/drivers/net/ethernet/cisco/enic/enic_admin.c +++ b/drivers/net/ethernet/cisco/enic/enic_admin.c @@ -4,6 +4,7 @@ #include #include #include +#include #include "vnic_dev.h" #include "vnic_wq.h" @@ -15,9 +16,15 @@ #include "enic.h" #include "enic_admin.h" #include "cq_desc.h" +#include "cq_enet_desc.h" #include "wq_enet_desc.h" #include "rq_enet_desc.h" +/* Retry interval for a failed admin RQ refill. Short so the control + * channel recovers quickly once memory is available again. + */ +#define ENIC_ADMIN_RQ_REFILL_RETRY_MS 100 + /* Clean up any admin WQ buffers still held by hardware at close time. * Normally buffers are freed inline after send completion, but a timed-out * send intentionally leaves the buffer live until the queue is stopped. @@ -94,6 +101,283 @@ static void enic_admin_rq_drain(struct enic *enic) vnic_rq_clean(&enic->admin_rq, enic_admin_rq_buf_clean); } +static unsigned int enic_admin_cq_color(void *cq_desc, unsigned int desc_size) +{ + u8 type_color = *((u8 *)cq_desc + desc_size - 1); + + return (type_color >> CQ_DESC_COLOR_SHIFT) & CQ_DESC_COLOR_MASK; +} + +unsigned int enic_admin_wq_cq_service(struct enic *enic) +{ + struct vnic_cq *cq = &enic->admin_cq[0]; + unsigned int work = 0; + void *desc; + + desc = vnic_cq_to_clean(cq); + while (enic_admin_cq_color(desc, cq->ring.desc_size) != + cq->last_color) { + vnic_cq_inc_to_clean(cq); + work++; + desc = vnic_cq_to_clean(cq); + } + + return work; +} + +/* Upper bound on pending admin messages. A buggy or hostile VF could flood + * the PF admin channel faster than admin_msg_work drains it; cap the backlog + * so a guest cannot drive the host out of memory. + */ +#define ENIC_ADMIN_MSG_MAX 256 + +static void enic_admin_msg_enqueue(struct enic *enic, void *buf, + unsigned int len) +{ + struct enic_admin_msg *msg; + + msg = kmalloc(struct_size(msg, data, len), GFP_KERNEL); + if (!msg) + return; + + msg->len = len; + memcpy(msg->data, buf, len); + + spin_lock(&enic->admin_msg_lock); + if (enic->admin_msg_count >= ENIC_ADMIN_MSG_MAX) { + spin_unlock(&enic->admin_msg_lock); + kfree(msg); + if (net_ratelimit()) + netdev_warn(enic->netdev, + "admin msg backlog full (%u); dropping\n", + ENIC_ADMIN_MSG_MAX); + return; + } + list_add_tail(&msg->list, &enic->admin_msg_list); + enic->admin_msg_count++; + spin_unlock(&enic->admin_msg_lock); +} + +unsigned int enic_admin_rq_cq_service(struct enic *enic) +{ + struct vnic_cq *cq = &enic->admin_cq[1]; + struct vnic_rq *rq = &enic->admin_rq; + struct cq_enet_rq_desc *rq_desc; + struct vnic_rq_buf *buf; + u16 bwf, bytes_written; + unsigned int work = 0; + void *desc; + + /* The admin RQ and its CQ form a single in-order channel: firmware + * posts exactly one CQE per consumed RQ descriptor, in submission + * order. Each CQE therefore pairs with rq->to_clean below without a + * completed_index cross-check, mirroring the in-order assumption of + * the main enic RX path. + */ + desc = vnic_cq_to_clean(cq); + while (enic_admin_cq_color(desc, cq->ring.desc_size) != + cq->last_color) { + /* Ensure DMA descriptor fields are read after + * the color/valid check. dma_rmb() is the + * correct barrier for DMA-written descriptors. + */ + dma_rmb(); + buf = rq->to_clean; + + /* Decode the actual number of bytes hardware wrote into + * the RX buffer. buf->len is the static allocation size + * (ENIC_ADMIN_BUF_SIZE); copying that many bytes would read + * beyond the actual DMA payload. bytes_written_flags is at + * the same offset in every cq_enet_rq_desc[_32|_64] variant. + */ + rq_desc = desc; + bwf = le16_to_cpu(rq_desc->bytes_written_flags); + bytes_written = bwf & CQ_ENET_RQ_DESC_BYTES_WRITTEN_MASK; + if (bytes_written > buf->len) + goto next_desc; + + dma_sync_single_for_cpu(&enic->pdev->dev, + buf->dma_addr, buf->len, + DMA_FROM_DEVICE); + + /* Drop on hardware error indications. Admin messages + * are internal to the VIC, not received over the wire. + * Firmware sets TRUNCATED when the message does not fit + * in the posted buffer, and FCS_OK is always set on + * healthy admin completions. + */ + if (bwf & CQ_ENET_RQ_DESC_FLAGS_TRUNCATED) { + netdev_warn_once(enic->netdev, + "admin RQ: truncated message dropped\n"); + goto next_desc; + } + if (!(rq_desc->flags & CQ_ENET_RQ_DESC_FLAGS_FCS_OK)) { + netdev_warn_once(enic->netdev, + "admin RQ: bad FCS, dropping message\n"); + goto next_desc; + } + + enic_admin_msg_enqueue(enic, buf->os_buf, bytes_written); + +next_desc: + enic_admin_rq_buf_clean(rq, rq->to_clean); + rq->to_clean = rq->to_clean->next; + rq->ring.desc_avail++; + + vnic_cq_inc_to_clean(cq); + work++; + desc = vnic_cq_to_clean(cq); + } + + if (enic_admin_rq_fill(enic, GFP_KERNEL)) { + /* Some RX buffers could not be reposted (transient memory + * pressure). If the ring is left empty the channel would stall + * with no completion to drive the next refill, so arm a delayed + * re-run of this poll work (the sole owner of the admin RQ ring) + * to repost buffers and re-arm the RQ from a single context. + */ + if (net_ratelimit()) + netdev_warn(enic->netdev, + "admin RQ refill failed; scheduling retry\n"); + schedule_delayed_work(&enic->admin_poll_work, + msecs_to_jiffies(ENIC_ADMIN_RQ_REFILL_RETRY_MS)); + } + + return work; +} + +static irqreturn_t enic_admin_isr_msix(int irq, void *data) +{ + struct enic *enic = data; + + schedule_delayed_work(&enic->admin_poll_work, 0); + + return IRQ_HANDLED; +} + +static void enic_admin_msg_work_handler(struct work_struct *work) +{ + struct enic *enic = container_of(work, struct enic, admin_msg_work); + struct enic_admin_msg *msg, *tmp; + LIST_HEAD(local_list); + + spin_lock_bh(&enic->admin_msg_lock); + list_splice_init(&enic->admin_msg_list, &local_list); + enic->admin_msg_count = 0; + spin_unlock_bh(&enic->admin_msg_lock); + + list_for_each_entry_safe(msg, tmp, &local_list, list) { + if (enic->admin_rq_handler) + enic->admin_rq_handler(enic, msg->data, msg->len); + list_del(&msg->list); + kfree(msg); + } +} + +static void enic_admin_poll_work_handler(struct work_struct *work) +{ + struct enic *enic = container_of(to_delayed_work(work), struct enic, + admin_poll_work); + unsigned int credits; + unsigned int rq_work; + + /* Snapshot the pending credit count before draining so we acknowledge + * exactly what the hardware reported for this interrupt. Credits that + * accrue while enic_admin_rq_cq_service() runs are left for the next + * interrupt, which is harmless on this low-rate control path. + */ + credits = vnic_intr_credits(&enic->admin_intr); + + rq_work = enic_admin_rq_cq_service(enic); + + if (rq_work > 0) + schedule_work(&enic->admin_msg_work); + + /* Acknowledge the snapshotted credits and unmask the vector. Unlike + * the NAPI data path, the admin channel is not re-polled, so the vector + * must be re-armed here to receive the next completion. The unmask is + * applied through the interrupt mask register independently of the + * credit count, so returning zero credits on a spurious wakeup still + * re-arms the vector. + */ + vnic_intr_return_credits(&enic->admin_intr, + credits, + 1 /* unmask */, 0); +} + +static int enic_admin_setup_intr(struct enic *enic) +{ + unsigned int intr_index = enic->intr_count; + int err; + + if (vnic_dev_get_intr_mode(enic->vdev) != VNIC_DEV_INTR_MODE_MSIX || + intr_index >= enic->intr_avail) + return -ENODEV; + + /* The admin INTR uses a slot in the same RES_TYPE_INTR_CTRL + * strided array of per-vector control blocks (mask, coalescing + * timer, credit return) that the data-path IRQs occupy in BAR0. + * vnic_intr_alloc() defaults to RES_TYPE_INTR_CTRL, which is what + * we want here. + */ + err = vnic_intr_alloc(enic->vdev, &enic->admin_intr, intr_index); + if (err) { + netdev_warn(enic->netdev, + "Failed to alloc admin intr at index %u: %d\n", + intr_index, err); + return err; + } + + enic->admin_intr_index = intr_index; + + /* Mask the admin vector before requesting the IRQ so an early or + * spurious completion cannot run the poll handler against the + * not-yet-initialised admin rings. enic_admin_channel_open() unmasks + * it only after the rings are initialised and filled. + */ + vnic_intr_mask(&enic->admin_intr); + + /* A V2 VF opens the admin channel during probe, before + * register_netdev() resolves the "eth%d" name template, so using + * netdev->name here would register the literal "eth%d-admin" in + * /proc/interrupts. Use the already-stable PCI device name instead. + */ + snprintf(enic->msix[intr_index].devname, + sizeof(enic->msix[intr_index].devname), + "%s-admin", pci_name(enic->pdev)); + enic->msix[intr_index].isr = enic_admin_isr_msix; + enic->msix[intr_index].devid = enic; + + err = request_irq(enic->msix_entry[intr_index].vector, + enic->msix[intr_index].isr, 0, + enic->msix[intr_index].devname, + enic->msix[intr_index].devid); + if (err) { + netdev_warn(enic->netdev, + "Failed to request admin MSI-X irq: %d\n", err); + vnic_intr_free(&enic->admin_intr); + return err; + } + + enic->msix[intr_index].requested = 1; + + netdev_dbg(enic->netdev, + "admin channel using MSI-X interrupt (index %u)\n", + intr_index); + + return 0; +} + +static void enic_admin_teardown_intr(struct enic *enic) +{ + unsigned int intr_index = enic->admin_intr_index; + + free_irq(enic->msix_entry[intr_index].vector, + enic->msix[intr_index].devid); + cancel_delayed_work_sync(&enic->admin_poll_work); + enic->msix[intr_index].requested = 0; +} + static int enic_admin_qp_type_set(struct enic *enic, u32 enable) { u64 a0 = QP_TYPE_ADMIN, a1 = enable; @@ -173,6 +457,7 @@ static int enic_admin_alloc_resources(struct enic *enic) static void enic_admin_free_resources(struct enic *enic) { + vnic_intr_free(&enic->admin_intr); vnic_cq_free(&enic->admin_cq[1]); vnic_cq_free(&enic->admin_cq[0]); vnic_rq_free(&enic->admin_rq); @@ -181,6 +466,8 @@ static void enic_admin_free_resources(struct enic *enic) static void enic_admin_init_resources(struct enic *enic) { + unsigned int intr_offset = enic->admin_intr_index; + vnic_wq_init(&enic->admin_wq, 0, 0, 0); /* cq_index, err_intr_enable, err_intr_offset */ vnic_rq_init(&enic->admin_rq, @@ -189,20 +476,35 @@ static void enic_admin_init_resources(struct enic *enic) VNIC_CQ_FC_DISABLE, VNIC_CQ_COLOR_ENABLE, 0, 0, 1, /* cq_head, cq_tail, cq_tail_color */ - VNIC_CQ_INTR_DISABLE, + VNIC_CQ_INTR_DISABLE, /* polled synchronously by mbox send */ VNIC_CQ_ENTRY_ENABLE, VNIC_CQ_MSG_DISABLE, - 0, /* interrupt_offset */ + intr_offset, 0 /* cq_message_addr */); vnic_cq_init(&enic->admin_cq[1], VNIC_CQ_FC_DISABLE, VNIC_CQ_COLOR_ENABLE, 0, 0, 1, /* cq_head, cq_tail, cq_tail_color */ - VNIC_CQ_INTR_DISABLE, + VNIC_CQ_INTR_ENABLE, VNIC_CQ_ENTRY_ENABLE, VNIC_CQ_MSG_DISABLE, - 0, /* interrupt_offset */ + intr_offset, 0 /* cq_message_addr */); + vnic_intr_init(&enic->admin_intr, + 0, 0, 1); /* coalescing_timer, coalescing_type, mask_on_assertion */ +} + +static void enic_admin_msg_drain(struct enic *enic) +{ + struct enic_admin_msg *msg, *tmp; + + spin_lock_bh(&enic->admin_msg_lock); + list_for_each_entry_safe(msg, tmp, &enic->admin_msg_list, list) { + list_del(&msg->list); + kfree(msg); + } + enic->admin_msg_count = 0; + spin_unlock_bh(&enic->admin_msg_lock); } int enic_admin_channel_open(struct enic *enic) @@ -220,6 +522,19 @@ int enic_admin_channel_open(struct enic *enic) return err; } + spin_lock_init(&enic->admin_msg_lock); + INIT_LIST_HEAD(&enic->admin_msg_list); + INIT_WORK(&enic->admin_msg_work, enic_admin_msg_work_handler); + INIT_DELAYED_WORK(&enic->admin_poll_work, enic_admin_poll_work_handler); + + err = enic_admin_setup_intr(enic); + if (err) { + netdev_err(enic->netdev, + "Admin channel requires MSI-X, SR-IOV unavailable: %d\n", + err); + goto free_resources; + } + enic_admin_init_resources(enic); vnic_wq_enable(&enic->admin_wq); @@ -239,17 +554,31 @@ int enic_admin_channel_open(struct enic *enic) goto disable_queues; } + vnic_intr_unmask(&enic->admin_intr); + + netdev_dbg(enic->netdev, + "admin channel open: intr=%u wq_avail=%u rq_avail=%u cq0_color=%u cq1_color=%u\n", + enic->admin_intr_index, + vnic_wq_desc_avail(&enic->admin_wq), + vnic_rq_desc_avail(&enic->admin_rq), + enic->admin_cq[0].last_color, + enic->admin_cq[1].last_color); + enic->admin_chan_up = true; return 0; disable_queues: + enic_admin_teardown_intr(enic); enic_admin_qp_type_set(enic, QP_DISABLE); if (vnic_wq_disable(&enic->admin_wq)) netdev_warn(enic->netdev, "Failed to disable admin WQ\n"); if (vnic_rq_disable(&enic->admin_rq)) netdev_warn(enic->netdev, "Failed to disable admin RQ\n"); + cancel_work_sync(&enic->admin_msg_work); + enic_admin_msg_drain(enic); enic_admin_rq_drain(enic); +free_resources: enic_admin_free_resources(enic); return err; } @@ -268,6 +597,13 @@ void enic_admin_channel_close(struct enic *enic) if (!enic->admin_chan_up) return; + netdev_dbg(enic->netdev, "admin channel close\n"); + + vnic_intr_mask(&enic->admin_intr); + enic_admin_teardown_intr(enic); + cancel_work_sync(&enic->admin_msg_work); + enic_admin_msg_drain(enic); + enic_admin_qp_type_set(enic, QP_DISABLE); err = vnic_wq_disable(&enic->admin_wq); @@ -283,6 +619,7 @@ void enic_admin_channel_close(struct enic *enic) enic_admin_rq_drain(enic); vnic_cq_clean(&enic->admin_cq[0]); vnic_cq_clean(&enic->admin_cq[1]); + vnic_intr_clean(&enic->admin_intr); enic_admin_free_resources(enic); enic->admin_chan_up = false; diff --git a/drivers/net/ethernet/cisco/enic/enic_admin.h b/drivers/net/ethernet/cisco/enic/enic_admin.h index 569aadeb9312..62c80220b0ca 100644 --- a/drivers/net/ethernet/cisco/enic/enic_admin.h +++ b/drivers/net/ethernet/cisco/enic/enic_admin.h @@ -9,7 +9,19 @@ struct enic; +/* Wrapper for received admin messages queued for deferred processing. + * The admin CQ poll work handler enqueues these; a separate work handler + * processes them where sleeping (mutex, GFP_KERNEL) is safe. + */ +struct enic_admin_msg { + struct list_head list; + unsigned int len; + u8 data[] __aligned(8); +}; + int enic_admin_channel_open(struct enic *enic); void enic_admin_channel_close(struct enic *enic); +unsigned int enic_admin_wq_cq_service(struct enic *enic); +unsigned int enic_admin_rq_cq_service(struct enic *enic); #endif /* _ENIC_ADMIN_H_ */