RDMA/bnxt_re: Add UAPI to share a page with user space

Gen P7 adapters require to share a toggle value for CQ
and SRQ. This is received by the driver as part of
interrupt notifications and needs to be shared with the
user space. Add a new UAPI infrastructure to get the
shared page for CQ and SRQ.

Signed-off-by: Selvin Xavier <selvin.xavier@broadcom.com>
Link: https://lore.kernel.org/r/1702535484-26844-2-git-send-email-selvin.xavier@broadcom.com
Signed-off-by: Leon Romanovsky <leon@kernel.org>

2 files changed, 106 insertions, 0 deletions

diff --git a/drivers/infiniband/hw/bnxt_re/ib_verbs.c b/drivers/infiniband/hw/bnxt_re/ib_verbs.c
index e7ef099c3edd..758ea02e1d13 100644
--- a/drivers/infiniband/hw/bnxt_re/ib_verbs.c
+++ b/drivers/infiniband/hw/bnxt_re/ib_verbs.c
@@ -567,6 +567,7 @@ bnxt_re_mmap_entry_insert(struct bnxt_re_ucontext *uctx, u64 mem_offset,
 	case BNXT_RE_MMAP_WC_DB:
 	case BNXT_RE_MMAP_DBR_BAR:
 	case BNXT_RE_MMAP_DBR_PAGE:
+	case BNXT_RE_MMAP_TOGGLE_PAGE:
 		ret = rdma_user_mmap_entry_insert(&uctx->ib_uctx,
 						  &entry->rdma_entry, PAGE_SIZE);
 		break;
@@ -4254,6 +4255,7 @@ int bnxt_re_mmap(struct ib_ucontext *ib_uctx, struct vm_area_struct *vma)
 					rdma_entry);
 		break;
 	case BNXT_RE_MMAP_DBR_PAGE:
+	case BNXT_RE_MMAP_TOGGLE_PAGE:
 		/* Driver doesn't expect write access for user space */
 		if (vma->vm_flags & VM_WRITE)
 			return -EFAULT;
@@ -4430,8 +4432,111 @@ DECLARE_UVERBS_NAMED_METHOD(BNXT_RE_METHOD_NOTIFY_DRV);
 DECLARE_UVERBS_GLOBAL_METHODS(BNXT_RE_OBJECT_NOTIFY_DRV,
 			      &UVERBS_METHOD(BNXT_RE_METHOD_NOTIFY_DRV));
 
+/* Toggle MEM */
+static int UVERBS_HANDLER(BNXT_RE_METHOD_GET_TOGGLE_MEM)(struct uverbs_attr_bundle *attrs)
+{
+	struct ib_uobject *uobj = uverbs_attr_get_uobject(attrs, BNXT_RE_TOGGLE_MEM_HANDLE);
+	enum bnxt_re_mmap_flag mmap_flag = BNXT_RE_MMAP_TOGGLE_PAGE;
+	enum bnxt_re_get_toggle_mem_type res_type;
+	struct bnxt_re_user_mmap_entry *entry;
+	struct bnxt_re_ucontext *uctx;
+	struct ib_ucontext *ib_uctx;
+	struct bnxt_re_dev *rdev;
+	u64 mem_offset;
+	u64 addr = 0;
+	u32 length;
+	u32 offset;
+	int err;
+
+	ib_uctx = ib_uverbs_get_ucontext(attrs);
+	if (IS_ERR(ib_uctx))
+		return PTR_ERR(ib_uctx);
+
+	err = uverbs_get_const(&res_type, attrs, BNXT_RE_TOGGLE_MEM_TYPE);
+	if (err)
+		return err;
+
+	uctx = container_of(ib_uctx, struct bnxt_re_ucontext, ib_uctx);
+	rdev = uctx->rdev;
+
+	switch (res_type) {
+	case BNXT_RE_CQ_TOGGLE_MEM:
+	case BNXT_RE_SRQ_TOGGLE_MEM:
+		break;
+
+	default:
+		return -EOPNOTSUPP;
+	}
+
+	entry = bnxt_re_mmap_entry_insert(uctx, addr, mmap_flag, &mem_offset);
+	if (!entry)
+		return -ENOMEM;
+
+	uobj->object = entry;
+	uverbs_finalize_uobj_create(attrs, BNXT_RE_TOGGLE_MEM_HANDLE);
+	err = uverbs_copy_to(attrs, BNXT_RE_TOGGLE_MEM_MMAP_PAGE,
+			     &mem_offset, sizeof(mem_offset));
+	if (err)
+		return err;
+
+	err = uverbs_copy_to(attrs, BNXT_RE_TOGGLE_MEM_MMAP_LENGTH,
+			     &length, sizeof(length));
+	if (err)
+		return err;
+
+	err = uverbs_copy_to(attrs, BNXT_RE_TOGGLE_MEM_MMAP_OFFSET,
+			     &offset, sizeof(length));
+	if (err)
+		return err;
+
+	return 0;
+}
+
+static int get_toggle_mem_obj_cleanup(struct ib_uobject *uobject,
+				      enum rdma_remove_reason why,
+				      struct uverbs_attr_bundle *attrs)
+{
+	struct  bnxt_re_user_mmap_entry *entry = uobject->object;
+
+	rdma_user_mmap_entry_remove(&entry->rdma_entry);
+	return 0;
+}
+
+DECLARE_UVERBS_NAMED_METHOD(BNXT_RE_METHOD_GET_TOGGLE_MEM,
+			    UVERBS_ATTR_IDR(BNXT_RE_TOGGLE_MEM_HANDLE,
+					    BNXT_RE_OBJECT_GET_TOGGLE_MEM,
+					    UVERBS_ACCESS_NEW,
+					    UA_MANDATORY),
+			    UVERBS_ATTR_CONST_IN(BNXT_RE_TOGGLE_MEM_TYPE,
+						 enum bnxt_re_get_toggle_mem_type,
+						 UA_MANDATORY),
+			    UVERBS_ATTR_PTR_IN(BNXT_RE_TOGGLE_MEM_RES_ID,
+					       UVERBS_ATTR_TYPE(u32),
+					       UA_MANDATORY),
+			    UVERBS_ATTR_PTR_OUT(BNXT_RE_TOGGLE_MEM_MMAP_PAGE,
+						UVERBS_ATTR_TYPE(u64),
+						UA_MANDATORY),
+			    UVERBS_ATTR_PTR_OUT(BNXT_RE_TOGGLE_MEM_MMAP_OFFSET,
+						UVERBS_ATTR_TYPE(u32),
+						UA_MANDATORY),
+			    UVERBS_ATTR_PTR_OUT(BNXT_RE_TOGGLE_MEM_MMAP_LENGTH,
+						UVERBS_ATTR_TYPE(u32),
+						UA_MANDATORY));
+
+DECLARE_UVERBS_NAMED_METHOD_DESTROY(BNXT_RE_METHOD_RELEASE_TOGGLE_MEM,
+				    UVERBS_ATTR_IDR(BNXT_RE_RELEASE_TOGGLE_MEM_HANDLE,
+						    BNXT_RE_OBJECT_GET_TOGGLE_MEM,
+						    UVERBS_ACCESS_DESTROY,
+						    UA_MANDATORY));
+
+DECLARE_UVERBS_NAMED_OBJECT(BNXT_RE_OBJECT_GET_TOGGLE_MEM,
+			    UVERBS_TYPE_ALLOC_IDR(get_toggle_mem_obj_cleanup),
+			    &UVERBS_METHOD(BNXT_RE_METHOD_GET_TOGGLE_MEM),
+			    &UVERBS_METHOD(BNXT_RE_METHOD_RELEASE_TOGGLE_MEM));
+
 const struct uapi_definition bnxt_re_uapi_defs[] = {
 	UAPI_DEF_CHAIN_OBJ_TREE_NAMED(BNXT_RE_OBJECT_ALLOC_PAGE),
 	UAPI_DEF_CHAIN_OBJ_TREE_NAMED(BNXT_RE_OBJECT_NOTIFY_DRV),
+	UAPI_DEF_CHAIN_OBJ_TREE_NAMED(BNXT_RE_OBJECT_GET_TOGGLE_MEM),
 	{}
 };
diff --git a/drivers/infiniband/hw/bnxt_re/ib_verbs.h b/drivers/infiniband/hw/bnxt_re/ib_verbs.h
index 98baea98fc17..da3fe018f255 100644
--- a/drivers/infiniband/hw/bnxt_re/ib_verbs.h
+++ b/drivers/infiniband/hw/bnxt_re/ib_verbs.h
@@ -149,6 +149,7 @@ enum bnxt_re_mmap_flag {
 	BNXT_RE_MMAP_WC_DB,
 	BNXT_RE_MMAP_DBR_PAGE,
 	BNXT_RE_MMAP_DBR_BAR,
+	BNXT_RE_MMAP_TOGGLE_PAGE,
 };
 
 struct bnxt_re_user_mmap_entry {