IB/uverbs: Extend modify_qp and support packet pacing

An new uverbs command ib_uverbs_ex_modify_qp is added to support more QP
attributes. User driver should choose to call the legacy/extended API
based on input mask.

IB_USER_LAST_QP_ATTR_MASK is added to indicated the maximum bit position
which supports legacy ib_uverbs_modify_qp.
IB_USER_LEGACY_LAST_QP_ATTR_MASK indicates the maximum bit position
which supports ib_uverbs_ex_modify_qp, the value of this mask should be
updated if new mask is added later.

Along with this change, rate_limit is supported by the extended command,
user driver could use it to control packet packing.

Signed-off-by: Bodong Wang <bodong@mellanox.com>
Reviewed-by: Matan Barak <matanb@mellanox.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Doug Ledford <dledford@redhat.com>

4 files changed, 146 insertions, 69 deletions

diff --git a/drivers/infiniband/core/uverbs.h b/drivers/infiniband/core/uverbs.h
index df26a741cda6..455034ac994e 100644
--- a/drivers/infiniband/core/uverbs.h
+++ b/drivers/infiniband/core/uverbs.h
@@ -289,5 +289,6 @@ IB_UVERBS_DECLARE_EX_CMD(modify_wq);
 IB_UVERBS_DECLARE_EX_CMD(destroy_wq);
 IB_UVERBS_DECLARE_EX_CMD(create_rwq_ind_table);
 IB_UVERBS_DECLARE_EX_CMD(destroy_rwq_ind_table);
+IB_UVERBS_DECLARE_EX_CMD(modify_qp);
 
 #endif /* UVERBS_H */
diff --git a/drivers/infiniband/core/uverbs_cmd.c b/drivers/infiniband/core/uverbs_cmd.c
index cdb935ddab69..09b649159e6c 100644
--- a/drivers/infiniband/core/uverbs_cmd.c
+++ b/drivers/infiniband/core/uverbs_cmd.c
@@ -2328,96 +2328,88 @@ static int modify_qp_mask(enum ib_qp_type qp_type, int mask)
         }
 }
 
-ssize_t ib_uverbs_modify_qp(struct ib_uverbs_file *file,
-                            struct ib_device *ib_dev,
-                            const char __user *buf, int in_len,
-                            int out_len)
+static int modify_qp(struct ib_uverbs_file *file,
+                     struct ib_uverbs_ex_modify_qp *cmd, struct ib_udata *udata)
 {
-        struct ib_uverbs_modify_qp cmd;
-        struct ib_udata            udata;
-        struct ib_qp              *qp;
-        struct ib_qp_attr         *attr;
-        int                        ret;
-
-        if (copy_from_user(&cmd, buf, sizeof cmd))
-                return -EFAULT;
-
-        INIT_UDATA(&udata, buf + sizeof cmd, NULL, in_len - sizeof cmd,
-                   out_len);
+        struct ib_qp_attr *attr;
+        struct ib_qp *qp;
+        int ret;
 
         attr = kmalloc(sizeof *attr, GFP_KERNEL);
         if (!attr)
                 return -ENOMEM;
 
-        qp = idr_read_qp(cmd.qp_handle, file->ucontext);
+        qp = idr_read_qp(cmd->base.qp_handle, file->ucontext);
         if (!qp) {
                 ret = -EINVAL;
                 goto out;
         }
 
-        attr->qp_state            = cmd.qp_state;
-        attr->cur_qp_state        = cmd.cur_qp_state;
-        attr->path_mtu            = cmd.path_mtu;
-        attr->path_mig_state      = cmd.path_mig_state;
-        attr->qkey                = cmd.qkey;
-        attr->rq_psn              = cmd.rq_psn;
-        attr->sq_psn              = cmd.sq_psn;
-        attr->dest_qp_num         = cmd.dest_qp_num;
-        attr->qp_access_flags     = cmd.qp_access_flags;
-        attr->pkey_index          = cmd.pkey_index;
-        attr->alt_pkey_index      = cmd.alt_pkey_index;
-        attr->en_sqd_async_notify = cmd.en_sqd_async_notify;
-        attr->max_rd_atomic       = cmd.max_rd_atomic;
-        attr->max_dest_rd_atomic  = cmd.max_dest_rd_atomic;
-        attr->min_rnr_timer       = cmd.min_rnr_timer;
-        attr->port_num            = cmd.port_num;
-        attr->timeout             = cmd.timeout;
-        attr->retry_cnt           = cmd.retry_cnt;
-        attr->rnr_retry           = cmd.rnr_retry;
-        attr->alt_port_num        = cmd.alt_port_num;
-        attr->alt_timeout         = cmd.alt_timeout;
-
-        memcpy(attr->ah_attr.grh.dgid.raw, cmd.dest.dgid, 16);
-        attr->ah_attr.grh.flow_label        = cmd.dest.flow_label;
-        attr->ah_attr.grh.sgid_index        = cmd.dest.sgid_index;
-        attr->ah_attr.grh.hop_limit         = cmd.dest.hop_limit;
-        attr->ah_attr.grh.traffic_class     = cmd.dest.traffic_class;
-        attr->ah_attr.dlid                  = cmd.dest.dlid;
-        attr->ah_attr.sl                    = cmd.dest.sl;
-        attr->ah_attr.src_path_bits         = cmd.dest.src_path_bits;
-        attr->ah_attr.static_rate           = cmd.dest.static_rate;
-        attr->ah_attr.ah_flags              = cmd.dest.is_global ? IB_AH_GRH : 0;
-        attr->ah_attr.port_num              = cmd.dest.port_num;
-
-        memcpy(attr->alt_ah_attr.grh.dgid.raw, cmd.alt_dest.dgid, 16);
-        attr->alt_ah_attr.grh.flow_label    = cmd.alt_dest.flow_label;
-        attr->alt_ah_attr.grh.sgid_index    = cmd.alt_dest.sgid_index;
-        attr->alt_ah_attr.grh.hop_limit     = cmd.alt_dest.hop_limit;
-        attr->alt_ah_attr.grh.traffic_class = cmd.alt_dest.traffic_class;
-        attr->alt_ah_attr.dlid              = cmd.alt_dest.dlid;
-        attr->alt_ah_attr.sl                = cmd.alt_dest.sl;
-        attr->alt_ah_attr.src_path_bits     = cmd.alt_dest.src_path_bits;
-        attr->alt_ah_attr.static_rate       = cmd.alt_dest.static_rate;
-        attr->alt_ah_attr.ah_flags          = cmd.alt_dest.is_global ? IB_AH_GRH : 0;
-        attr->alt_ah_attr.port_num          = cmd.alt_dest.port_num;
+        attr->qp_state            = cmd->base.qp_state;
+        attr->cur_qp_state        = cmd->base.cur_qp_state;
+        attr->path_mtu            = cmd->base.path_mtu;
+        attr->path_mig_state      = cmd->base.path_mig_state;
+        attr->qkey                = cmd->base.qkey;
+        attr->rq_psn              = cmd->base.rq_psn;
+        attr->sq_psn              = cmd->base.sq_psn;
+        attr->dest_qp_num         = cmd->base.dest_qp_num;
+        attr->qp_access_flags     = cmd->base.qp_access_flags;
+        attr->pkey_index          = cmd->base.pkey_index;
+        attr->alt_pkey_index      = cmd->base.alt_pkey_index;
+        attr->en_sqd_async_notify = cmd->base.en_sqd_async_notify;
+        attr->max_rd_atomic       = cmd->base.max_rd_atomic;
+        attr->max_dest_rd_atomic  = cmd->base.max_dest_rd_atomic;
+        attr->min_rnr_timer       = cmd->base.min_rnr_timer;
+        attr->port_num            = cmd->base.port_num;
+        attr->timeout             = cmd->base.timeout;
+        attr->retry_cnt           = cmd->base.retry_cnt;
+        attr->rnr_retry           = cmd->base.rnr_retry;
+        attr->alt_port_num        = cmd->base.alt_port_num;
+        attr->alt_timeout         = cmd->base.alt_timeout;
+        attr->rate_limit          = cmd->rate_limit;
+
+        memcpy(attr->ah_attr.grh.dgid.raw, cmd->base.dest.dgid, 16);
+        attr->ah_attr.grh.flow_label    = cmd->base.dest.flow_label;
+        attr->ah_attr.grh.sgid_index    = cmd->base.dest.sgid_index;
+        attr->ah_attr.grh.hop_limit     = cmd->base.dest.hop_limit;
+        attr->ah_attr.grh.traffic_class = cmd->base.dest.traffic_class;
+        attr->ah_attr.dlid              = cmd->base.dest.dlid;
+        attr->ah_attr.sl                = cmd->base.dest.sl;
+        attr->ah_attr.src_path_bits     = cmd->base.dest.src_path_bits;
+        attr->ah_attr.static_rate       = cmd->base.dest.static_rate;
+        attr->ah_attr.ah_flags          = cmd->base.dest.is_global ?
+                                          IB_AH_GRH : 0;
+        attr->ah_attr.port_num          = cmd->base.dest.port_num;
+
+        memcpy(attr->alt_ah_attr.grh.dgid.raw, cmd->base.alt_dest.dgid, 16);
+        attr->alt_ah_attr.grh.flow_label    = cmd->base.alt_dest.flow_label;
+        attr->alt_ah_attr.grh.sgid_index    = cmd->base.alt_dest.sgid_index;
+        attr->alt_ah_attr.grh.hop_limit     = cmd->base.alt_dest.hop_limit;
+        attr->alt_ah_attr.grh.traffic_class = cmd->base.alt_dest.traffic_class;
+        attr->alt_ah_attr.dlid              = cmd->base.alt_dest.dlid;
+        attr->alt_ah_attr.sl                = cmd->base.alt_dest.sl;
+        attr->alt_ah_attr.src_path_bits     = cmd->base.alt_dest.src_path_bits;
+        attr->alt_ah_attr.static_rate       = cmd->base.alt_dest.static_rate;
+        attr->alt_ah_attr.ah_flags          = cmd->base.alt_dest.is_global ?
+                                              IB_AH_GRH : 0;
+        attr->alt_ah_attr.port_num          = cmd->base.alt_dest.port_num;
 
         if (qp->real_qp == qp) {
-                if (cmd.attr_mask & IB_QP_AV) {
+                if (cmd->base.attr_mask & IB_QP_AV) {
                         ret = ib_resolve_eth_dmac(qp->device, &attr->ah_attr);
                         if (ret)
                                 goto release_qp;
                 }
                 ret = qp->device->modify_qp(qp, attr,
-                        modify_qp_mask(qp->qp_type, cmd.attr_mask), &udata);
+                                            modify_qp_mask(qp->qp_type,
+                                                           cmd->base.attr_mask),
+                                            udata);
         } else {
-                ret = ib_modify_qp(qp, attr, modify_qp_mask(qp->qp_type, cmd.attr_mask));
+                ret = ib_modify_qp(qp, attr,
+                                   modify_qp_mask(qp->qp_type,
+                                                  cmd->base.attr_mask));
         }
 
-        if (ret)
-                goto release_qp;
-
-        ret = in_len;
-
 release_qp:
         put_qp_read(qp);
 
@@ -2427,6 +2419,68 @@ out:
         return ret;
 }
 
+ssize_t ib_uverbs_modify_qp(struct ib_uverbs_file *file,
+                            struct ib_device *ib_dev,
+                            const char __user *buf, int in_len,
+                            int out_len)
+{
+        struct ib_uverbs_ex_modify_qp cmd = {};
+        struct ib_udata udata;
+        int ret;
+
+        if (copy_from_user(&cmd.base, buf, sizeof(cmd.base)))
+                return -EFAULT;
+
+        if (cmd.base.attr_mask &
+            ~((IB_USER_LEGACY_LAST_QP_ATTR_MASK << 1) - 1))
+                return -EOPNOTSUPP;
+
+        INIT_UDATA(&udata, buf + sizeof(cmd.base), NULL,
+                   in_len - sizeof(cmd.base), out_len);
+
+        ret = modify_qp(file, &cmd, &udata);
+        if (ret)
+                return ret;
+
+        return in_len;
+}
+
+int ib_uverbs_ex_modify_qp(struct ib_uverbs_file *file,
+                           struct ib_device *ib_dev,
+                           struct ib_udata *ucore,
+                           struct ib_udata *uhw)
+{
+        struct ib_uverbs_ex_modify_qp cmd = {};
+        int ret;
+
+        /*
+         * Last bit is reserved for extending the attr_mask by
+         * using another field.
+         */
+        BUILD_BUG_ON(IB_USER_LAST_QP_ATTR_MASK == (1 << 31));
+
+        if (ucore->inlen < sizeof(cmd.base))
+                return -EINVAL;
+
+        ret = ib_copy_from_udata(&cmd, ucore, min(sizeof(cmd), ucore->inlen));
+        if (ret)
+                return ret;
+
+        if (cmd.base.attr_mask &
+            ~((IB_USER_LAST_QP_ATTR_MASK << 1) - 1))
+                return -EOPNOTSUPP;
+
+        if (ucore->inlen > sizeof(cmd)) {
+                if (ib_is_udata_cleared(ucore, sizeof(cmd),
+                                        ucore->inlen - sizeof(cmd)))
+                        return -EOPNOTSUPP;
+        }
+
+        ret = modify_qp(file, &cmd, uhw);
+
+        return ret;
+}
+
 ssize_t ib_uverbs_destroy_qp(struct ib_uverbs_file *file,
                              struct ib_device *ib_dev,
                              const char __user *buf, int in_len,
diff --git a/drivers/infiniband/core/uverbs_main.c b/drivers/infiniband/core/uverbs_main.c
index 0012fa58c105..80839c31c887 100644
--- a/drivers/infiniband/core/uverbs_main.c
+++ b/drivers/infiniband/core/uverbs_main.c
@@ -137,6 +137,7 @@ static int (*uverbs_ex_cmd_table[])(struct ib_uverbs_file *file,
         [IB_USER_VERBS_EX_CMD_DESTROY_WQ]       = ib_uverbs_ex_destroy_wq,
         [IB_USER_VERBS_EX_CMD_CREATE_RWQ_IND_TBL] = ib_uverbs_ex_create_rwq_ind_table,
         [IB_USER_VERBS_EX_CMD_DESTROY_RWQ_IND_TBL] = ib_uverbs_ex_destroy_rwq_ind_table,
+        [IB_USER_VERBS_EX_CMD_MODIFY_QP]        = ib_uverbs_ex_modify_qp,
 };
 
 static void ib_uverbs_add_one(struct ib_device *device);
diff --git a/include/uapi/rdma/ib_user_verbs.h b/include/uapi/rdma/ib_user_verbs.h
index 90ba5e88ec00..dfdfe4e92d31 100644
--- a/include/uapi/rdma/ib_user_verbs.h
+++ b/include/uapi/rdma/ib_user_verbs.h
@@ -37,6 +37,7 @@
 #define IB_USER_VERBS_H
 
 #include <linux/types.h>
+#include <rdma/ib_verbs.h>
 
 /*
  * Increment this value if any changes that break userspace ABI
@@ -93,6 +94,7 @@ enum {
         IB_USER_VERBS_EX_CMD_QUERY_DEVICE = IB_USER_VERBS_CMD_QUERY_DEVICE,
         IB_USER_VERBS_EX_CMD_CREATE_CQ = IB_USER_VERBS_CMD_CREATE_CQ,
         IB_USER_VERBS_EX_CMD_CREATE_QP = IB_USER_VERBS_CMD_CREATE_QP,
+        IB_USER_VERBS_EX_CMD_MODIFY_QP = IB_USER_VERBS_CMD_MODIFY_QP,
         IB_USER_VERBS_EX_CMD_CREATE_FLOW = IB_USER_VERBS_CMD_THRESHOLD,
         IB_USER_VERBS_EX_CMD_DESTROY_FLOW,
         IB_USER_VERBS_EX_CMD_CREATE_WQ,
@@ -545,6 +547,14 @@ enum {
         IB_UVERBS_CREATE_QP_SUP_COMP_MASK = IB_UVERBS_CREATE_QP_MASK_IND_TABLE,
 };
 
+enum {
+        IB_USER_LEGACY_LAST_QP_ATTR_MASK = IB_QP_DEST_QPN
+};
+
+enum {
+        IB_USER_LAST_QP_ATTR_MASK = IB_QP_RATE_LIMIT
+};
+
 struct ib_uverbs_ex_create_qp {
         __u64 user_handle;
         __u32 pd_handle;
@@ -684,9 +694,20 @@ struct ib_uverbs_modify_qp {
         __u64 driver_data[0];
 };
 
+struct ib_uverbs_ex_modify_qp {
+        struct ib_uverbs_modify_qp base;
+        __u32   rate_limit;
+        __u32   reserved;
+};
+
 struct ib_uverbs_modify_qp_resp {
 };
 
+struct ib_uverbs_ex_modify_qp_resp {
+        __u32  comp_mask;
+        __u32  response_length;
+};
+
 struct ib_uverbs_destroy_qp {
         __u64 response;
         __u32 qp_handle;