IB/mlx5: Let read user wqe also from SRQ buffer
Reading a WQE from SRQ is almost identical to reading from regular RQ.
The differences are the size of the queue, the size of a WQE and buffer
location.
Make necessary changes to mlx5_ib_read_user_wqe() to let it read a WQE
from a SRQ or RQ by caller choice.
Signed-off-by: Moni Shoua <monis@mellanox.com>
Reviewed-by: Majd Dibbiny <majd@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
diff --git a/drivers/infiniband/hw/mlx5/qp.c b/drivers/infiniband/hw/mlx5/qp.c
index 529e76f..8cde49d 100644
--- a/drivers/infiniband/hw/mlx5/qp.c
+++ b/drivers/infiniband/hw/mlx5/qp.c
@@ -109,75 +109,173 @@ static int is_sqp(enum ib_qp_type qp_type)
}
/**
- * mlx5_ib_read_user_wqe() - Copy a user-space WQE to kernel space.
+ * mlx5_ib_read_user_wqe_common() - Copy a WQE (or part of) from user WQ
+ * to kernel buffer
*
- * @qp: QP to copy from.
- * @send: copy from the send queue when non-zero, use the receive queue
- * otherwise.
- * @wqe_index: index to start copying from. For send work queues, the
- * wqe_index is in units of MLX5_SEND_WQE_BB.
- * For receive work queue, it is the number of work queue
- * element in the queue.
- * @buffer: destination buffer.
- * @length: maximum number of bytes to copy.
+ * @umem: User space memory where the WQ is
+ * @buffer: buffer to copy to
+ * @buflen: buffer length
+ * @wqe_index: index of WQE to copy from
+ * @wq_offset: offset to start of WQ
+ * @wq_wqe_cnt: number of WQEs in WQ
+ * @wq_wqe_shift: log2 of WQE size
+ * @bcnt: number of bytes to copy
+ * @bytes_copied: number of bytes to copy (return value)
*
- * Copies at least a single WQE, but may copy more data.
+ * Copies from start of WQE bcnt or less bytes.
+ * Does not gurantee to copy the entire WQE.
*
- * Return: the number of bytes copied, or an error code.
+ * Return: zero on success, or an error code.
*/
-int mlx5_ib_read_user_wqe(struct mlx5_ib_qp *qp, int send, int wqe_index,
- void *buffer, u32 length,
- struct mlx5_ib_qp_base *base)
+static int mlx5_ib_read_user_wqe_common(struct ib_umem *umem,
+ void *buffer,
+ u32 buflen,
+ int wqe_index,
+ int wq_offset,
+ int wq_wqe_cnt,
+ int wq_wqe_shift,
+ int bcnt,
+ size_t *bytes_copied)
{
- struct ib_device *ibdev = qp->ibqp.device;
- struct mlx5_ib_dev *dev = to_mdev(ibdev);
- struct mlx5_ib_wq *wq = send ? &qp->sq : &qp->rq;
- size_t offset;
- size_t wq_end;
- struct ib_umem *umem = base->ubuffer.umem;
- u32 first_copy_length;
- int wqe_length;
+ size_t offset = wq_offset + ((wqe_index % wq_wqe_cnt) << wq_wqe_shift);
+ size_t wq_end = wq_offset + (wq_wqe_cnt << wq_wqe_shift);
+ size_t copy_length;
int ret;
- if (wq->wqe_cnt == 0) {
- mlx5_ib_dbg(dev, "mlx5_ib_read_user_wqe for a QP with wqe_cnt == 0. qp_type: 0x%x\n",
- qp->ibqp.qp_type);
- return -EINVAL;
- }
+ /* don't copy more than requested, more than buffer length or
+ * beyond WQ end
+ */
+ copy_length = min_t(u32, buflen, wq_end - offset);
+ copy_length = min_t(u32, copy_length, bcnt);
- offset = wq->offset + ((wqe_index % wq->wqe_cnt) << wq->wqe_shift);
- wq_end = wq->offset + (wq->wqe_cnt << wq->wqe_shift);
-
- if (send && length < sizeof(struct mlx5_wqe_ctrl_seg))
- return -EINVAL;
-
- if (offset > umem->length ||
- (send && offset + sizeof(struct mlx5_wqe_ctrl_seg) > umem->length))
- return -EINVAL;
-
- first_copy_length = min_t(u32, offset + length, wq_end) - offset;
- ret = ib_umem_copy_from(buffer, umem, offset, first_copy_length);
+ ret = ib_umem_copy_from(buffer, umem, offset, copy_length);
if (ret)
return ret;
- if (send) {
- struct mlx5_wqe_ctrl_seg *ctrl = buffer;
- int ds = be32_to_cpu(ctrl->qpn_ds) & MLX5_WQE_CTRL_DS_MASK;
+ if (!ret && bytes_copied)
+ *bytes_copied = copy_length;
- wqe_length = ds * MLX5_WQE_DS_UNITS;
- } else {
- wqe_length = 1 << wq->wqe_shift;
- }
+ return 0;
+}
- if (wqe_length <= first_copy_length)
- return first_copy_length;
+int mlx5_ib_read_user_wqe_sq(struct mlx5_ib_qp *qp,
+ int wqe_index,
+ void *buffer,
+ int buflen,
+ size_t *bc)
+{
+ struct mlx5_ib_qp_base *base = &qp->trans_qp.base;
+ struct ib_umem *umem = base->ubuffer.umem;
+ struct mlx5_ib_wq *wq = &qp->sq;
+ struct mlx5_wqe_ctrl_seg *ctrl;
+ size_t bytes_copied;
+ size_t bytes_copied2;
+ size_t wqe_length;
+ int ret;
+ int ds;
- ret = ib_umem_copy_from(buffer + first_copy_length, umem, wq->offset,
- wqe_length - first_copy_length);
+ if (buflen < sizeof(*ctrl))
+ return -EINVAL;
+
+ /* at first read as much as possible */
+ ret = mlx5_ib_read_user_wqe_common(umem,
+ buffer,
+ buflen,
+ wqe_index,
+ wq->offset,
+ wq->wqe_cnt,
+ wq->wqe_shift,
+ buflen,
+ &bytes_copied);
if (ret)
return ret;
- return wqe_length;
+ /* we need at least control segment size to proceed */
+ if (bytes_copied < sizeof(*ctrl))
+ return -EINVAL;
+
+ ctrl = buffer;
+ ds = be32_to_cpu(ctrl->qpn_ds) & MLX5_WQE_CTRL_DS_MASK;
+ wqe_length = ds * MLX5_WQE_DS_UNITS;
+
+ /* if we copied enough then we are done */
+ if (bytes_copied >= wqe_length) {
+ *bc = bytes_copied;
+ return 0;
+ }
+
+ /* otherwise this a wrapped around wqe
+ * so read the remaining bytes starting
+ * from wqe_index 0
+ */
+ ret = mlx5_ib_read_user_wqe_common(umem,
+ buffer + bytes_copied,
+ buflen - bytes_copied,
+ 0,
+ wq->offset,
+ wq->wqe_cnt,
+ wq->wqe_shift,
+ wqe_length - bytes_copied,
+ &bytes_copied2);
+
+ if (ret)
+ return ret;
+ *bc = bytes_copied + bytes_copied2;
+ return 0;
+}
+
+int mlx5_ib_read_user_wqe_rq(struct mlx5_ib_qp *qp,
+ int wqe_index,
+ void *buffer,
+ int buflen,
+ size_t *bc)
+{
+ struct mlx5_ib_qp_base *base = &qp->trans_qp.base;
+ struct ib_umem *umem = base->ubuffer.umem;
+ struct mlx5_ib_wq *wq = &qp->rq;
+ size_t bytes_copied;
+ int ret;
+
+ ret = mlx5_ib_read_user_wqe_common(umem,
+ buffer,
+ buflen,
+ wqe_index,
+ wq->offset,
+ wq->wqe_cnt,
+ wq->wqe_shift,
+ buflen,
+ &bytes_copied);
+
+ if (ret)
+ return ret;
+ *bc = bytes_copied;
+ return 0;
+}
+
+int mlx5_ib_read_user_wqe_srq(struct mlx5_ib_srq *srq,
+ int wqe_index,
+ void *buffer,
+ int buflen,
+ size_t *bc)
+{
+ struct ib_umem *umem = srq->umem;
+ size_t bytes_copied;
+ int ret;
+
+ ret = mlx5_ib_read_user_wqe_common(umem,
+ buffer,
+ buflen,
+ wqe_index,
+ 0,
+ srq->msrq.max,
+ srq->msrq.wqe_shift,
+ buflen,
+ &bytes_copied);
+
+ if (ret)
+ return ret;
+ *bc = bytes_copied;
+ return 0;
}
static void mlx5_ib_qp_event(struct mlx5_core_qp *qp, int type)