Fwd: [PATCH for-next v5 09/10] RDMA/rxe: Implement memory access through MWs

["Pearson, Robert B" <rpearsonhpe@xxxxxxxxx>]

On 4/24/2021 11:23 PM, Zhu Yanjun wrote:
> On Fri, Apr 23, 2021 at 12:13 AM Bob Pearson <rpearsonhpe@xxxxxxxxx> 
> wrote:
> > Add code to implement memory access through memory windows.
> >
> > Signed-off-by: Bob Pearson <rpearson@xxxxxxx>
> > ---
> > v3:
> > Adjusted patch for collisions with v3 of "RDMA/rxe: Implement
> > invalidate MW operations" patch.
> > v2:
> > Removed a copy of changes in ea4922518940 "Fix missing acks from 
> > responder"
> > that was submitted separately.
> > ---
> > drivers/infiniband/sw/rxe/rxe_loc.h | 1 +
> > drivers/infiniband/sw/rxe/rxe_mw.c | 23 +++++++++++
> > drivers/infiniband/sw/rxe/rxe_resp.c | 55 +++++++++++++++++++--------
> > drivers/infiniband/sw/rxe/rxe_verbs.h | 11 ++++++
> > 4 files changed, 75 insertions(+), 15 deletions(-)
> >
> > diff --git a/drivers/infiniband/sw/rxe/rxe_loc.h 
> > b/drivers/infiniband/sw/rxe/rxe_loc.h
> > index bc0e484f8cde..076e1460577f 100644
> > --- a/drivers/infiniband/sw/rxe/rxe_loc.h
> > +++ b/drivers/infiniband/sw/rxe/rxe_loc.h
> > @@ -94,6 +94,7 @@ int rxe_alloc_mw(struct ib_mw *ibmw, struct 
> > ib_udata *udata);
> > int rxe_dealloc_mw(struct ib_mw *ibmw);
> > int rxe_bind_mw(struct rxe_qp *qp, struct rxe_send_wqe *wqe);
> > int rxe_invalidate_mw(struct rxe_qp *qp, u32 rkey);
> > +struct rxe_mw *lookup_mw(struct rxe_qp *qp, int access, u32 rkey);
> > void rxe_mw_cleanup(struct rxe_pool_entry *arg);
> >
> > /* rxe_net.c */
> > diff --git a/drivers/infiniband/sw/rxe/rxe_mw.c 
> > b/drivers/infiniband/sw/rxe/rxe_mw.c
> > index 00490f232fde..6ed36845c693 100644
> > --- a/drivers/infiniband/sw/rxe/rxe_mw.c
> > +++ b/drivers/infiniband/sw/rxe/rxe_mw.c
> > @@ -312,6 +312,29 @@ int rxe_invalidate_mw(struct rxe_qp *qp, u32 rkey)
> > return ret;
> > }
> >
> > +struct rxe_mw *lookup_mw(struct rxe_qp *qp, int access, u32 rkey)
> will this function lookup_mw be used outside of softroce?
> If not, how about changing the name from lookup_mw to rxe_lookup_mw?
>
> Thanks
> Zhu Yanjun

I would think the opposite is correct. If a name is used outside of the 
driver then the prefix reduces the chance

of a collision with some more global name. If it is only used locally in 
the driver this is less of an issue. Mostly

I have been following the rule that if a name is shared between files in 
rxe then add the prefix and if it is local

to a file (e.g. static) then drop it. Here I broke that and will make 
this change. If a routine is frequently used

for example to_rdev() then the prefix just gets in the way of clarity. 
The shared names are declared in rxe_loc.h.

The common names are defined in rxe_verbs.h.

Bob

> > +{
> > + struct rxe_dev *rxe = to_rdev(qp->ibqp.device);
> > + struct rxe_pd *pd = to_rpd(qp->ibqp.pd);
> > + struct rxe_mw *mw;
> > + int index = rkey >> 8;
> > +
> > + mw = rxe_pool_get_index(&rxe->mw_pool, index);
> > + if (!mw)
> > + return NULL;
> > +
> > + if (unlikely((mw_rkey(mw) != rkey) || mw_pd(mw) != pd ||
> > + (mw->ibmw.type == IB_MW_TYPE_2 && mw->qp != qp) ||
> > + (mw->length == 0) ||
> > + (access && !(access & mw->access)) ||
> > + mw->state != RXE_MW_STATE_VALID)) {
> > + rxe_drop_ref(mw);
> > + return NULL;
> > + }
> > +
> > + return mw;
> > +}
> > +
> > void rxe_mw_cleanup(struct rxe_pool_entry *elem)
> > {
> > struct rxe_mw *mw = container_of(elem, typeof(*mw), pelem);
> > diff --git a/drivers/infiniband/sw/rxe/rxe_resp.c 
> > b/drivers/infiniband/sw/rxe/rxe_resp.c
> > index 759e9789cd4d..9c8cbfbc8820 100644
> > --- a/drivers/infiniband/sw/rxe/rxe_resp.c
> > +++ b/drivers/infiniband/sw/rxe/rxe_resp.c
> > @@ -394,6 +394,7 @@ static enum resp_states check_rkey(struct rxe_qp *qp,
> > struct rxe_pkt_info *pkt)
> > {
> > struct rxe_mr *mr = NULL;
> > + struct rxe_mw *mw = NULL;
> > u64 va;
> > u32 rkey;
> > u32 resid;
> > @@ -405,6 +406,7 @@ static enum resp_states check_rkey(struct rxe_qp *qp,
> > if (pkt->mask & (RXE_READ_MASK | RXE_WRITE_MASK)) {
> > if (pkt->mask & RXE_RETH_MASK) {
> > qp->resp.va = reth_va(pkt);
> > + qp->resp.offset = 0;
> > qp->resp.rkey = reth_rkey(pkt);
> > qp->resp.resid = reth_len(pkt);
> > qp->resp.length = reth_len(pkt);
> > @@ -413,6 +415,7 @@ static enum resp_states check_rkey(struct rxe_qp *qp,
> > : IB_ACCESS_REMOTE_WRITE;
> > } else if (pkt->mask & RXE_ATOMIC_MASK) {
> > qp->resp.va = atmeth_va(pkt);
> > + qp->resp.offset = 0;
> > qp->resp.rkey = atmeth_rkey(pkt);
> > qp->resp.resid = sizeof(u64);
> > access = IB_ACCESS_REMOTE_ATOMIC;
> > @@ -432,18 +435,36 @@ static enum resp_states check_rkey(struct 
> > rxe_qp *qp,
> > resid = qp->resp.resid;
> > pktlen = payload_size(pkt);
> >
> > - mr = lookup_mr(qp->pd, access, rkey, RXE_LOOKUP_REMOTE);
> > - if (!mr) {
> > - state = RESPST_ERR_RKEY_VIOLATION;
> > - goto err;
> > - }
> > + if (rkey_is_mw(rkey)) {
> > + mw = lookup_mw(qp, access, rkey);
> > + if (!mw) {
> > + pr_err("%s: no MW matches rkey %#x\n", __func__, rkey);
> > + state = RESPST_ERR_RKEY_VIOLATION;
> > + goto err;
> > + }
> >
> > - if (unlikely(mr->state == RXE_MR_STATE_FREE)) {
> > - state = RESPST_ERR_RKEY_VIOLATION;
> > - goto err;
> > + mr = mw->mr;
> > + if (!mr) {
> > + pr_err("%s: MW doesn't have an MR\n", __func__);
> > + state = RESPST_ERR_RKEY_VIOLATION;
> > + goto err;
> > + }
> > +
> > + if (mw->access & IB_ZERO_BASED)
> > + qp->resp.offset = mw->addr;
> > +
> > + rxe_drop_ref(mw);
> > + rxe_add_ref(mr);
> > + } else {
> > + mr = lookup_mr(qp->pd, access, rkey, RXE_LOOKUP_REMOTE);
> > + if (!mr) {
> > + pr_err("%s: no MR matches rkey %#x\n", __func__, rkey);
> > + state = RESPST_ERR_RKEY_VIOLATION;
> > + goto err;
> > + }
> > }
> >
> > - if (mr_check_range(mr, va, resid)) {
> > + if (mr_check_range(mr, va + qp->resp.offset, resid)) {
> > state = RESPST_ERR_RKEY_VIOLATION;
> > goto err;
> > }
> > @@ -477,6 +498,9 @@ static enum resp_states check_rkey(struct rxe_qp *qp,
> > err:
> > if (mr)
> > rxe_drop_ref(mr);
> > + if (mw)
> > + rxe_drop_ref(mw);
> > +
> > return state;
> > }
> >
> > @@ -501,8 +525,8 @@ static enum resp_states write_data_in(struct 
> > rxe_qp *qp,
> > int err;
> > int data_len = payload_size(pkt);
> >
> > - err = rxe_mr_copy(qp->resp.mr, qp->resp.va, payload_addr(pkt), 
> > data_len,
> > - RXE_TO_MR_OBJ, NULL);
> > + err = rxe_mr_copy(qp->resp.mr, qp->resp.va + qp->resp.offset,
> > + payload_addr(pkt), data_len, RXE_TO_MR_OBJ, NULL);
> > if (err) {
> > rc = RESPST_ERR_RKEY_VIOLATION;
> > goto out;
> > @@ -521,7 +545,6 @@ static DEFINE_SPINLOCK(atomic_ops_lock);
> > static enum resp_states process_atomic(struct rxe_qp *qp,
> > struct rxe_pkt_info *pkt)
> > {
> > - u64 iova = atmeth_va(pkt);
> > u64 *vaddr;
> > enum resp_states ret;
> > struct rxe_mr *mr = qp->resp.mr;
> > @@ -531,7 +554,7 @@ static enum resp_states process_atomic(struct 
> > rxe_qp *qp,
> > goto out;
> > }
> >
> > - vaddr = iova_to_vaddr(mr, iova, sizeof(u64));
> > + vaddr = iova_to_vaddr(mr, qp->resp.va + qp->resp.offset, sizeof(u64));
> >
> > /* check vaddr is 8 bytes aligned. */
> > if (!vaddr || (uintptr_t)vaddr & 7) {
> > @@ -655,8 +678,10 @@ static enum resp_states read_reply(struct rxe_qp 
> > *qp,
> > res->type = RXE_READ_MASK;
> > res->replay = 0;
> >
> > - res->read.va = qp->resp.va;
> > - res->read.va_org = qp->resp.va;
> > + res->read.va = qp->resp.va +
> > + qp->resp.offset;
> > + res->read.va_org = qp->resp.va +
> > + qp->resp.offset;
> >
> > res->first_psn = req_pkt->psn;
> >
> > diff --git a/drivers/infiniband/sw/rxe/rxe_verbs.h 
> > b/drivers/infiniband/sw/rxe/rxe_verbs.h
> > index 74fcd871757d..f426bf30f86a 100644
> > --- a/drivers/infiniband/sw/rxe/rxe_verbs.h
> > +++ b/drivers/infiniband/sw/rxe/rxe_verbs.h
> > @@ -183,6 +183,7 @@ struct rxe_resp_info {
> >
> > /* RDMA read / atomic only */
> > u64 va;
> > + u64 offset;
> > struct rxe_mr *mr;
> > u32 resid;
> > u32 rkey;
> > @@ -480,6 +481,16 @@ static inline u32 mr_rkey(struct rxe_mr *mr)
> > return mr->ibmr.rkey;
> > }
> >
> > +static inline struct rxe_pd *mw_pd(struct rxe_mw *mw)
> rxe_mw_pd
No. See above.
> > +{
> > + return to_rpd(mw->ibmw.pd);
> > +}
> > +
> > +static inline u32 mw_rkey(struct rxe_mw *mw)
> rxe_mw_rkey
No.
> > +{
> > + return mw->ibmw.rkey;
> > +}
> > +
> > int rxe_register_device(struct rxe_dev *rxe, const char *ibdev_name);
> >
> > void rxe_mc_cleanup(struct rxe_pool_entry *arg);
> > --
> > 2.27.0