--- /dev/null
+/*
+ * Copyright (c) 2015 HGST, a Western Digital Company.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ */
+#include <linux/module.h>
+#include <linux/err.h>
+#include <linux/slab.h>
+#include <rdma/ib_verbs.h>
+
+/* # of WCs to poll for with a single call to ib_poll_cq */
+#define IB_POLL_BATCH 16
+
+/* # of WCs to iterate over before yielding */
+#define IB_POLL_BUDGET_IRQ 256
+#define IB_POLL_BUDGET_WORKQUEUE 65536
+
+#define IB_POLL_FLAGS \
+ (IB_CQ_NEXT_COMP | IB_CQ_REPORT_MISSED_EVENTS)
+
+static int __ib_process_cq(struct ib_cq *cq, int budget)
+{
+ int i, n, completed = 0;
+
+ while ((n = ib_poll_cq(cq, IB_POLL_BATCH, cq->wc)) > 0) {
+ for (i = 0; i < n; i++) {
+ struct ib_wc *wc = &cq->wc[i];
+
+ if (wc->wr_cqe)
+ wc->wr_cqe->done(cq, wc);
+ else
+ WARN_ON_ONCE(wc->status == IB_WC_SUCCESS);
+ }
+
+ completed += n;
+
+ if (n != IB_POLL_BATCH ||
+ (budget != -1 && completed >= budget))
+ break;
+ }
+
+ return completed;
+}
+
+/**
+ * ib_process_direct_cq - process a CQ in caller context
+ * @cq: CQ to process
+ * @budget: number of CQEs to poll for
+ *
+ * This function is used to process all outstanding CQ entries on a
+ * %IB_POLL_DIRECT CQ. It does not offload CQ processing to a different
+ * context and does not ask for completion interrupts from the HCA.
+ *
+ * Note: for compatibility reasons -1 can be passed in %budget for unlimited
+ * polling. Do not use this feature in new code, it will be removed soon.
+ */
+int ib_process_cq_direct(struct ib_cq *cq, int budget)
+{
+ WARN_ON_ONCE(cq->poll_ctx != IB_POLL_DIRECT);
+
+ return __ib_process_cq(cq, budget);
+}
+EXPORT_SYMBOL(ib_process_cq_direct);
+
+static void ib_cq_completion_direct(struct ib_cq *cq, void *private)
+{
+ WARN_ONCE(1, "got unsolicited completion for CQ 0x%p\n", cq);
+}
+
+static int ib_poll_handler(struct irq_poll *iop, int budget)
+{
+ struct ib_cq *cq = container_of(iop, struct ib_cq, iop);
+ int completed;
+
+ completed = __ib_process_cq(cq, budget);
+ if (completed < budget) {
+ irq_poll_complete(&cq->iop);
+ if (ib_req_notify_cq(cq, IB_POLL_FLAGS) > 0)
+ irq_poll_sched(&cq->iop);
+ }
+
+ return completed;
+}
+
+static void ib_cq_completion_softirq(struct ib_cq *cq, void *private)
+{
+ irq_poll_sched(&cq->iop);
+}
+
+static void ib_cq_poll_work(struct work_struct *work)
+{
+ struct ib_cq *cq = container_of(work, struct ib_cq, work);
+ int completed;
+
+ completed = __ib_process_cq(cq, IB_POLL_BUDGET_WORKQUEUE);
+ if (completed >= IB_POLL_BUDGET_WORKQUEUE ||
+ ib_req_notify_cq(cq, IB_POLL_FLAGS) > 0)
+ queue_work(ib_comp_wq, &cq->work);
+}
+
+static void ib_cq_completion_workqueue(struct ib_cq *cq, void *private)
+{
+ queue_work(ib_comp_wq, &cq->work);
+}
+
+/**
+ * ib_alloc_cq - allocate a completion queue
+ * @dev: device to allocate the CQ for
+ * @private: driver private data, accessible from cq->cq_context
+ * @nr_cqe: number of CQEs to allocate
+ * @comp_vector: HCA completion vectors for this CQ
+ * @poll_ctx: context to poll the CQ from.
+ *
+ * This is the proper interface to allocate a CQ for in-kernel users. A
+ * CQ allocated with this interface will automatically be polled from the
+ * specified context. The ULP needs must use wr->wr_cqe instead of wr->wr_id
+ * to use this CQ abstraction.
+ */
+struct ib_cq *ib_alloc_cq(struct ib_device *dev, void *private,
+ int nr_cqe, int comp_vector, enum ib_poll_context poll_ctx)
+{
+ struct ib_cq_init_attr cq_attr = {
+ .cqe = nr_cqe,
+ .comp_vector = comp_vector,
+ };
+ struct ib_cq *cq;
+ int ret = -ENOMEM;
+
+ cq = dev->create_cq(dev, &cq_attr, NULL, NULL);
+ if (IS_ERR(cq))
+ return cq;
+
+ cq->device = dev;
+ cq->uobject = NULL;
+ cq->event_handler = NULL;
+ cq->cq_context = private;
+ cq->poll_ctx = poll_ctx;
+ atomic_set(&cq->usecnt, 0);
+
+ cq->wc = kmalloc_array(IB_POLL_BATCH, sizeof(*cq->wc), GFP_KERNEL);
+ if (!cq->wc)
+ goto out_destroy_cq;
+
+ switch (cq->poll_ctx) {
+ case IB_POLL_DIRECT:
+ cq->comp_handler = ib_cq_completion_direct;
+ break;
+ case IB_POLL_SOFTIRQ:
+ cq->comp_handler = ib_cq_completion_softirq;
+
+ irq_poll_init(&cq->iop, IB_POLL_BUDGET_IRQ, ib_poll_handler);
+ ib_req_notify_cq(cq, IB_CQ_NEXT_COMP);
+ break;
+ case IB_POLL_WORKQUEUE:
+ cq->comp_handler = ib_cq_completion_workqueue;
+ INIT_WORK(&cq->work, ib_cq_poll_work);
+ ib_req_notify_cq(cq, IB_CQ_NEXT_COMP);
+ break;
+ default:
+ ret = -EINVAL;
+ goto out_free_wc;
+ }
+
+ return cq;
+
+out_free_wc:
+ kfree(cq->wc);
+out_destroy_cq:
+ cq->device->destroy_cq(cq);
+ return ERR_PTR(ret);
+}
+EXPORT_SYMBOL(ib_alloc_cq);
+
+/**
+ * ib_free_cq - free a completion queue
+ * @cq: completion queue to free.
+ */
+void ib_free_cq(struct ib_cq *cq)
+{
+ int ret;
+
+ if (WARN_ON_ONCE(atomic_read(&cq->usecnt)))
+ return;
+
+ switch (cq->poll_ctx) {
+ case IB_POLL_DIRECT:
+ break;
+ case IB_POLL_SOFTIRQ:
+ irq_poll_disable(&cq->iop);
+ break;
+ case IB_POLL_WORKQUEUE:
+ flush_work(&cq->work);
+ break;
+ default:
+ WARN_ON_ONCE(1);
+ }
+
+ kfree(cq->wc);
+ ret = cq->device->destroy_cq(cq);
+ WARN_ON_ONCE(ret);
+}
+EXPORT_SYMBOL(ib_free_cq);
#include <linux/scatterlist.h>
#include <linux/workqueue.h>
#include <linux/socket.h>
+#include <linux/irq_poll.h>
#include <uapi/linux/if_ether.h>
#include <linux/atomic.h>
#include <asm/uaccess.h>
extern struct workqueue_struct *ib_wq;
+extern struct workqueue_struct *ib_comp_wq;
union ib_gid {
u8 raw[16];
};
struct ib_wc {
- u64 wr_id;
+ union {
+ u64 wr_id;
+ struct ib_cqe *wr_cqe;
+ };
enum ib_wc_status status;
enum ib_wc_opcode opcode;
u32 vendor_err;
int mw_access_flags;
};
+struct ib_cqe {
+ void (*done)(struct ib_cq *cq, struct ib_wc *wc);
+};
+
struct ib_send_wr {
struct ib_send_wr *next;
- u64 wr_id;
+ union {
+ u64 wr_id;
+ struct ib_cqe *wr_cqe;
+ };
struct ib_sge *sg_list;
int num_sge;
enum ib_wr_opcode opcode;
struct ib_recv_wr {
struct ib_recv_wr *next;
- u64 wr_id;
+ union {
+ u64 wr_id;
+ struct ib_cqe *wr_cqe;
+ };
struct ib_sge *sg_list;
int num_sge;
};
typedef void (*ib_comp_handler)(struct ib_cq *cq, void *cq_context);
+enum ib_poll_context {
+ IB_POLL_DIRECT, /* caller context, no hw completions */
+ IB_POLL_SOFTIRQ, /* poll from softirq context */
+ IB_POLL_WORKQUEUE, /* poll from workqueue */
+};
+
struct ib_cq {
struct ib_device *device;
struct ib_uobject *uobject;
void *cq_context;
int cqe;
atomic_t usecnt; /* count number of work queues */
+ enum ib_poll_context poll_ctx;
+ struct ib_wc *wc;
+ union {
+ struct irq_poll iop;
+ struct work_struct work;
+ };
};
struct ib_srq {
return qp->device->post_recv(qp, recv_wr, bad_recv_wr);
}
+struct ib_cq *ib_alloc_cq(struct ib_device *dev, void *private,
+ int nr_cqe, int comp_vector, enum ib_poll_context poll_ctx);
+void ib_free_cq(struct ib_cq *cq);
+int ib_process_cq_direct(struct ib_cq *cq, int budget);
+
/**
* ib_create_cq - Creates a CQ on the specified device.
* @device: The device on which to create the CQ.
projects / linux-beck.git / commitdiff