RE: [PATCH for-next 1/2] RDMA/qedr: Notify user application if DPM is supported

Amrani, Ram
2017-06-22T11:27:43Z

> On Sun, Jun 18, 2017 at 04:01:10PM +0300, Ram Amrani wrote:
> > Direct Packet Mode support may be disabled, e.g, due to limited BAR
> > resources. Notifying the user application prevents wasting cycles
> > on attempting to send these kind of packets.
> >
> > Signed-off-by: Ram Amrani <Ram.Amrani-YGCgFSpz5w/QT0dZR+AlfA@public.gmane.org>
> > drivers/infiniband/hw/qedr/main.c | 1 +
> > drivers/infiniband/hw/qedr/qedr.h | 2 ++
> > drivers/infiniband/hw/qedr/verbs.c | 6 ++++++
> > include/uapi/rdma/qedr-abi.h | 1 +
> > 4 files changed, 10 insertions(+)
> >
> > diff --git a/drivers/infiniband/hw/qedr/main.c b/drivers/infiniband/hw/qedr/main.c
> > index 6a72095..d228718 100644
> > +++ b/drivers/infiniband/hw/qedr/main.c
> > @@ -778,6 +778,7 @@ static struct qedr_dev *qedr_add(struct qed_dev *cdev, struct pci_dev *pdev,
> > if (rc)
> > goto init_err;
> >
> > + dev->user_dpm_enabled = dev_info.user_dpm_enabled;
> > dev->num_hwfns = dev_info.common.num_hwfns;
> > dev->rdma_ctx = dev->ops->rdma_get_rdma_ctx(cdev);
> >
> > diff --git a/drivers/infiniband/hw/qedr/qedr.h b/drivers/infiniband/hw/qedr/qedr.h
> > index aa08c76..42af9b6 100644
> > +++ b/drivers/infiniband/hw/qedr/qedr.h
> > @@ -158,6 +158,8 @@ struct qedr_dev {
> > struct qedr_qp *gsi_qp;
> >
> > unsigned long enet_state;
> > +
> > + u8 user_dpm_enabled;
> > };
> >
> > #define QEDR_MAX_SQ_PBL (0x8000)
> > diff --git a/drivers/infiniband/hw/qedr/verbs.c b/drivers/infiniband/hw/qedr/verbs.c
> > index 17685cf..6a0acfa 100644
> > +++ b/drivers/infiniband/hw/qedr/verbs.c
> > @@ -335,6 +335,9 @@ static bool qedr_search_mmap(struct qedr_ucontext *uctx, u64 phy_addr,
> > return found;
> > }
> >
> > +#define QEDR_LIB_UCXT_SUPPORT(field, udata, value) \
> > + ((offsetof(struct qedr_alloc_ucontext_resp, field) < udata->outlen) ? \
> > + (value) : 0)
> > struct ib_ucontext *qedr_alloc_ucontext(struct ib_device *ibdev,
> > struct ib_udata *udata)
> > {
> > @@ -368,6 +371,9 @@ struct ib_ucontext *qedr_alloc_ucontext(struct ib_device *ibdev,
> >
> > memset(&uresp, 0, sizeof(uresp));
> >
> > + uresp.dpm_enabled = QEDR_LIB_UCXT_SUPPORT(dpm_enabled, udata,
> > + dev->user_dpm_enabled);
> > +
> > uresp.db_pa = ctx->dpi_phys_addr;
> > uresp.db_size = ctx->dpi_size;
> > uresp.max_send_wr = dev->attr.max_sqe;
> > diff --git a/include/uapi/rdma/qedr-abi.h b/include/uapi/rdma/qedr-abi.h
> > index 75c270d..2684004 100644
> > +++ b/include/uapi/rdma/qedr-abi.h
> > @@ -49,6 +49,7 @@ struct qedr_alloc_ucontext_resp {
> > __u32 sges_per_recv_wr;
> > __u32 sges_per_srq_wr;
> > __u32 max_cqes;
> > + __u8 dpm_enabled;
> > };
>
>
> Um, how is uapi compatibility achieved here? I don't see any size
> tests related to qedr_alloc_ucontext_resp:
>
> struct ib_ucontext *qedr_alloc_ucontext(struct ib_device *ibdev,
> struct ib_udata *udata)
> {
> struct qedr_alloc_ucontext_resp uresp;
> rc = ib_copy_to_udata(udata, &uresp, sizeof(uresp));
>
> Seems bad.
>
> Same with the other patch.
>
> Jason

By the way, if it wasn't clear, the aspect part of the compatibility is
achieved via the QEDR_LIB_UCXT_SUPPORT macro above.

Ram