From: Michael Margolin <mrgolin@amazon.com>
To: <jgg@nvidia.com>, <leon@kernel.org>, <linux-rdma@vger.kernel.org>
Cc: <sleybo@amazon.com>, <matua@amazon.com>, <gal.pressman@linux.dev>,
"Yonatan Nachum" <ynachum@amazon.com>
Subject: [PATCH for-next v9 3/6] RDMA/core: Expose Completion Counter capabilities to userspace
Date: Mon, 20 Jul 2026 07:58:03 +0000 [thread overview]
Message-ID: <20260720075806.12334-2-mrgolin@amazon.com> (raw)
In-Reply-To: <20260720075806.12334-1-mrgolin@amazon.com>
Add a dedicated query interface for completion counter capabilities
via UVERBS_METHOD_QUERY_COMP_CNTR_CAPS on the device object.
The query returns the maximum number of counters, maximum counter
value, and a bitmask of supported QP attach operations. Each field
is an optional ioctl attribute, allowing userspace to request only
the capabilities it needs.
Drivers implement the query_comp_cntr_caps operation to report
device-specific capabilities.
Reviewed-by: Yonatan Nachum <ynachum@amazon.com>
Signed-off-by: Michael Margolin <mrgolin@amazon.com>
---
drivers/infiniband/core/device.c | 1 +
.../infiniband/core/uverbs_std_types_device.c | 51 ++++++++++++++++++-
include/rdma/ib_verbs.h | 9 ++++
include/uapi/rdma/ib_user_ioctl_cmds.h | 7 +++
4 files changed, 67 insertions(+), 1 deletion(-)
diff --git a/drivers/infiniband/core/device.c b/drivers/infiniband/core/device.c
index a4c57279f19d..ddf75867ac61 100644
--- a/drivers/infiniband/core/device.c
+++ b/drivers/infiniband/core/device.c
@@ -2829,6 +2829,7 @@ void ib_set_device_ops(struct ib_device *dev, const struct ib_device_ops *ops)
SET_DEVICE_OP(dev_ops, post_srq_recv);
SET_DEVICE_OP(dev_ops, process_mad);
SET_DEVICE_OP(dev_ops, query_ah);
+ SET_DEVICE_OP(dev_ops, query_comp_cntr_caps);
SET_DEVICE_OP(dev_ops, query_device);
SET_DEVICE_OP(dev_ops, query_gid);
SET_DEVICE_OP(dev_ops, query_pkey);
diff --git a/drivers/infiniband/core/uverbs_std_types_device.c b/drivers/infiniband/core/uverbs_std_types_device.c
index 12ca15739cd2..ce0a7de00405 100644
--- a/drivers/infiniband/core/uverbs_std_types_device.c
+++ b/drivers/infiniband/core/uverbs_std_types_device.c
@@ -472,6 +472,42 @@ static int UVERBS_HANDLER(UVERBS_METHOD_QUERY_GID_ENTRY)(
return ret;
}
+static int UVERBS_HANDLER(UVERBS_METHOD_QUERY_COMP_CNTR_CAPS)(
+ struct uverbs_attr_bundle *attrs)
+{
+ struct ib_comp_cntr_caps caps = {};
+ struct ib_ucontext *ucontext;
+ struct ib_device *ib_dev;
+ int ret;
+
+ ucontext = ib_uverbs_get_ucontext(attrs);
+ if (IS_ERR(ucontext))
+ return PTR_ERR(ucontext);
+ ib_dev = ucontext->device;
+
+ if (!ib_dev->ops.query_comp_cntr_caps)
+ return -EOPNOTSUPP;
+
+ ret = ib_dev->ops.query_comp_cntr_caps(ib_dev, &caps, attrs);
+ if (ret)
+ return ret;
+
+ ret = uverbs_copy_to(attrs, UVERBS_ATTR_QUERY_COMP_CNTR_CAPS_MAX_COUNTERS,
+ &caps.max_counters, sizeof(caps.max_counters));
+ if (IS_UVERBS_COPY_ERR(ret))
+ return ret;
+
+ ret = uverbs_copy_to(attrs, UVERBS_ATTR_QUERY_COMP_CNTR_CAPS_MAX_VALUE,
+ &caps.max_value, sizeof(caps.max_value));
+ if (IS_UVERBS_COPY_ERR(ret))
+ return ret;
+
+ ret = uverbs_copy_to(attrs, UVERBS_ATTR_QUERY_COMP_CNTR_CAPS_SUPPORTED_QP_ATTACH_OPS,
+ &caps.supported_qp_attach_ops,
+ sizeof(caps.supported_qp_attach_ops));
+ return IS_UVERBS_COPY_ERR(ret) ? ret : 0;
+}
+
DECLARE_UVERBS_NAMED_METHOD(
UVERBS_METHOD_GET_CONTEXT,
UVERBS_ATTR_PTR_OUT(UVERBS_ATTR_GET_CONTEXT_NUM_COMP_VECTORS,
@@ -542,6 +578,18 @@ DECLARE_UVERBS_NAMED_METHOD(
netdev_ifindex),
UA_MANDATORY));
+DECLARE_UVERBS_NAMED_METHOD(
+ UVERBS_METHOD_QUERY_COMP_CNTR_CAPS,
+ UVERBS_ATTR_PTR_OUT(UVERBS_ATTR_QUERY_COMP_CNTR_CAPS_MAX_COUNTERS,
+ UVERBS_ATTR_TYPE(u32),
+ UA_OPTIONAL),
+ UVERBS_ATTR_PTR_OUT(UVERBS_ATTR_QUERY_COMP_CNTR_CAPS_MAX_VALUE,
+ UVERBS_ATTR_TYPE(u64),
+ UA_OPTIONAL),
+ UVERBS_ATTR_PTR_OUT(UVERBS_ATTR_QUERY_COMP_CNTR_CAPS_SUPPORTED_QP_ATTACH_OPS,
+ UVERBS_ATTR_TYPE(u32),
+ UA_OPTIONAL));
+
DECLARE_UVERBS_GLOBAL_METHODS(UVERBS_OBJECT_DEVICE,
&UVERBS_METHOD(UVERBS_METHOD_GET_CONTEXT),
&UVERBS_METHOD(UVERBS_METHOD_INVOKE_WRITE),
@@ -550,7 +598,8 @@ DECLARE_UVERBS_GLOBAL_METHODS(UVERBS_OBJECT_DEVICE,
&UVERBS_METHOD(UVERBS_METHOD_QUERY_PORT_SPEED),
&UVERBS_METHOD(UVERBS_METHOD_QUERY_CONTEXT),
&UVERBS_METHOD(UVERBS_METHOD_QUERY_GID_TABLE),
- &UVERBS_METHOD(UVERBS_METHOD_QUERY_GID_ENTRY));
+ &UVERBS_METHOD(UVERBS_METHOD_QUERY_GID_ENTRY),
+ &UVERBS_METHOD(UVERBS_METHOD_QUERY_COMP_CNTR_CAPS));
const struct uapi_definition uverbs_def_obj_device[] = {
UAPI_DEF_CHAIN_OBJ_TREE_NAMED(UVERBS_OBJECT_DEVICE),
diff --git a/include/rdma/ib_verbs.h b/include/rdma/ib_verbs.h
index 84a8904fbad4..033f4a2c965f 100644
--- a/include/rdma/ib_verbs.h
+++ b/include/rdma/ib_verbs.h
@@ -1755,6 +1755,12 @@ enum ib_qp_attach_comp_cntr_op {
IB_QP_ATTACH_COMP_CNTR_OP_REMOTE_RDMA_WRITE = IB_UVERBS_QP_ATTACH_COMP_CNTR_OP_REMOTE_RDMA_WRITE,
};
+struct ib_comp_cntr_caps {
+ u64 max_value;
+ u32 max_counters;
+ u32 supported_qp_attach_ops; /* Bitmask of enum ib_qp_attach_comp_cntr_op */
+};
+
struct ib_comp_cntr {
struct ib_device *device;
struct ib_uobject *uobject;
@@ -2689,6 +2695,9 @@ struct ib_device_ops {
int (*modify_comp_cntr)(struct ib_comp_cntr *cc, enum ib_comp_cntr_entry entry,
enum ib_comp_cntr_modify_op op, u64 value);
int (*read_comp_cntr)(struct ib_comp_cntr *cc, enum ib_comp_cntr_entry entry, u64 *value);
+ int (*query_comp_cntr_caps)(struct ib_device *dev,
+ struct ib_comp_cntr_caps *caps,
+ struct uverbs_attr_bundle *attrs);
struct ib_mr *(*get_dma_mr)(struct ib_pd *pd, int mr_access_flags);
struct ib_mr *(*reg_user_mr)(struct ib_pd *pd, u64 start, u64 length,
u64 virt_addr, int mr_access_flags,
diff --git a/include/uapi/rdma/ib_user_ioctl_cmds.h b/include/uapi/rdma/ib_user_ioctl_cmds.h
index 19a94b91987e..6a3d59d03f54 100644
--- a/include/uapi/rdma/ib_user_ioctl_cmds.h
+++ b/include/uapi/rdma/ib_user_ioctl_cmds.h
@@ -76,6 +76,7 @@ enum uverbs_methods_device {
UVERBS_METHOD_QUERY_GID_TABLE,
UVERBS_METHOD_QUERY_GID_ENTRY,
UVERBS_METHOD_QUERY_PORT_SPEED,
+ UVERBS_METHOD_QUERY_COMP_CNTR_CAPS,
};
enum uverbs_attrs_invoke_write_cmd_attr_ids {
@@ -94,6 +95,12 @@ enum uverbs_attrs_query_port_speed_cmd_attr_ids {
UVERBS_ATTR_QUERY_PORT_SPEED_RESP,
};
+enum uverbs_attrs_query_comp_cntr_caps_attr_ids {
+ UVERBS_ATTR_QUERY_COMP_CNTR_CAPS_MAX_COUNTERS,
+ UVERBS_ATTR_QUERY_COMP_CNTR_CAPS_MAX_VALUE,
+ UVERBS_ATTR_QUERY_COMP_CNTR_CAPS_SUPPORTED_QP_ATTACH_OPS,
+};
+
enum uverbs_attrs_get_context_attr_ids {
UVERBS_ATTR_GET_CONTEXT_NUM_COMP_VECTORS,
UVERBS_ATTR_GET_CONTEXT_CORE_SUPPORT,
--
2.47.3
next prev parent reply other threads:[~2026-07-20 7:58 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-07-20 7:58 [PATCH for-next v9 2/6] RDMA/core: Prevent destroying in-use completion counters Michael Margolin
2026-07-20 7:58 ` Michael Margolin [this message]
2026-07-20 7:58 ` [PATCH for-next v9 4/6] RDMA/core: Add Completion Counters to resource tracking Michael Margolin
2026-07-20 7:58 ` [PATCH for-next v9 5/6] RDMA/efa: Update device interface Michael Margolin
2026-07-20 7:58 ` [PATCH for-next v9 6/6] RDMA/efa: Add Completion Counters support Michael Margolin
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