IB/rdmavt: Add per verb driver callback checking
authorDennis Dalessandro <dennis.dalessandro@intel.com>
Sun, 14 Feb 2016 20:10:37 +0000 (12:10 -0800)
committerDoug Ledford <dledford@redhat.com>
Fri, 11 Mar 2016 01:38:09 +0000 (20:38 -0500)
For each verb validate that all requirements for driver callbacks are met.
If a function is called without checking for a valid pointer, it is a
required function. Also document what each callback function does.

Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
drivers/infiniband/sw/rdmavt/vt.c
include/rdma/rdma_vt.h

index f5cb09b718bef38192083666602b4f42d37d4c88..9566a920a244b3e1628f611b7467b3a05ecbbfbc 100644 (file)
@@ -325,12 +325,375 @@ static int rvt_get_port_immutable(struct ib_device *ibdev, u8 port_num,
        return 0;
 }
 
-/*
- * Check driver override. If driver passes a value use it, otherwise we use our
- * own value.
- */
-#define CHECK_DRIVER_OVERRIDE(rdi, x) \
-       rdi->ibdev.x = rdi->ibdev.x ? : rvt_ ##x
+enum {
+       MISC,
+       QUERY_DEVICE,
+       MODIFY_DEVICE,
+       QUERY_PORT,
+       MODIFY_PORT,
+       QUERY_PKEY,
+       QUERY_GID,
+       ALLOC_UCONTEXT,
+       DEALLOC_UCONTEXT,
+       GET_PORT_IMMUTABLE,
+       CREATE_QP,
+       MODIFY_QP,
+       DESTROY_QP,
+       QUERY_QP,
+       POST_SEND,
+       POST_RECV,
+       POST_SRQ_RECV,
+       CREATE_AH,
+       DESTROY_AH,
+       MODIFY_AH,
+       QUERY_AH,
+       CREATE_SRQ,
+       MODIFY_SRQ,
+       DESTROY_SRQ,
+       QUERY_SRQ,
+       ATTACH_MCAST,
+       DETACH_MCAST,
+       GET_DMA_MR,
+       REG_USER_MR,
+       DEREG_MR,
+       ALLOC_MR,
+       ALLOC_FMR,
+       MAP_PHYS_FMR,
+       UNMAP_FMR,
+       DEALLOC_FMR,
+       MMAP,
+       CREATE_CQ,
+       DESTROY_CQ,
+       POLL_CQ,
+       REQ_NOTFIY_CQ,
+       RESIZE_CQ,
+       ALLOC_PD,
+       DEALLOC_PD,
+       _VERB_IDX_MAX /* Must always be last! */
+};
+
+static inline int check_driver_override(struct rvt_dev_info *rdi,
+                                       size_t offset, void *func)
+{
+       if (!*(void **)((void *)&rdi->ibdev + offset)) {
+               *(void **)((void *)&rdi->ibdev + offset) = func;
+               return 0;
+       }
+
+       return 1;
+}
+
+static int check_support(struct rvt_dev_info *rdi, int verb)
+{
+       switch (verb) {
+       case MISC:
+               /*
+                * These functions are not part of verbs specifically but are
+                * required for rdmavt to function.
+                */
+               if ((!rdi->driver_f.port_callback) ||
+                   (!rdi->driver_f.get_card_name) ||
+                   (!rdi->driver_f.get_pci_dev))
+                       return -EINVAL;
+               break;
+
+       case QUERY_DEVICE:
+               check_driver_override(rdi, offsetof(struct ib_device,
+                                                   query_device),
+                                                   rvt_query_device);
+               break;
+
+       case MODIFY_DEVICE:
+               /*
+                * rdmavt does not support modify device currently drivers must
+                * provide.
+                */
+               if (!check_driver_override(rdi, offsetof(struct ib_device,
+                                                        modify_device),
+                                          rvt_modify_device))
+                       return -EOPNOTSUPP;
+               break;
+
+       case QUERY_PORT:
+               if (!check_driver_override(rdi, offsetof(struct ib_device,
+                                                        query_port),
+                                          rvt_query_port))
+                       if (!rdi->driver_f.query_port_state)
+                               return -EINVAL;
+               break;
+
+       case MODIFY_PORT:
+               if (!check_driver_override(rdi, offsetof(struct ib_device,
+                                                        modify_port),
+                                          rvt_modify_port))
+                       if (!rdi->driver_f.cap_mask_chg ||
+                           !rdi->driver_f.shut_down_port)
+                               return -EINVAL;
+               break;
+
+       case QUERY_PKEY:
+               check_driver_override(rdi, offsetof(struct ib_device,
+                                                   query_pkey),
+                                     rvt_query_pkey);
+               break;
+
+       case QUERY_GID:
+               if (!check_driver_override(rdi, offsetof(struct ib_device,
+                                                        query_gid),
+                                          rvt_query_gid))
+                       if (!rdi->driver_f.get_guid_be)
+                               return -EINVAL;
+               break;
+
+       case ALLOC_UCONTEXT:
+               check_driver_override(rdi, offsetof(struct ib_device,
+                                                   alloc_ucontext),
+                                     rvt_alloc_ucontext);
+               break;
+
+       case DEALLOC_UCONTEXT:
+               check_driver_override(rdi, offsetof(struct ib_device,
+                                                   dealloc_ucontext),
+                                     rvt_dealloc_ucontext);
+               break;
+
+       case GET_PORT_IMMUTABLE:
+               check_driver_override(rdi, offsetof(struct ib_device,
+                                                   get_port_immutable),
+                                     rvt_get_port_immutable);
+               break;
+
+       case CREATE_QP:
+               if (!check_driver_override(rdi, offsetof(struct ib_device,
+                                                        create_qp),
+                                          rvt_create_qp))
+                       if (!rdi->driver_f.qp_priv_alloc ||
+                           !rdi->driver_f.qp_priv_free ||
+                           !rdi->driver_f.notify_qp_reset ||
+                           !rdi->driver_f.flush_qp_waiters ||
+                           !rdi->driver_f.stop_send_queue ||
+                           !rdi->driver_f.quiesce_qp)
+                               return -EINVAL;
+               break;
+
+       case MODIFY_QP:
+               if (!check_driver_override(rdi, offsetof(struct ib_device,
+                                                        modify_qp),
+                                          rvt_modify_qp))
+                       if (!rdi->driver_f.notify_qp_reset ||
+                           !rdi->driver_f.schedule_send ||
+                           !rdi->driver_f.get_pmtu_from_attr ||
+                           !rdi->driver_f.flush_qp_waiters ||
+                           !rdi->driver_f.stop_send_queue ||
+                           !rdi->driver_f.quiesce_qp ||
+                           !rdi->driver_f.notify_error_qp ||
+                           !rdi->driver_f.mtu_from_qp ||
+                           !rdi->driver_f.mtu_to_path_mtu ||
+                           !rdi->driver_f.shut_down_port ||
+                           !rdi->driver_f.cap_mask_chg)
+                               return -EINVAL;
+               break;
+
+       case DESTROY_QP:
+               if (!check_driver_override(rdi, offsetof(struct ib_device,
+                                                        destroy_qp),
+                                          rvt_destroy_qp))
+                       if (!rdi->driver_f.qp_priv_free ||
+                           !rdi->driver_f.notify_qp_reset ||
+                           !rdi->driver_f.flush_qp_waiters ||
+                           !rdi->driver_f.stop_send_queue ||
+                           !rdi->driver_f.quiesce_qp)
+                               return -EINVAL;
+               break;
+
+       case QUERY_QP:
+               check_driver_override(rdi, offsetof(struct ib_device,
+                                                   query_qp),
+                                                   rvt_query_qp);
+               break;
+
+       case POST_SEND:
+               if (!check_driver_override(rdi, offsetof(struct ib_device,
+                                                        post_send),
+                                          rvt_post_send))
+                       if (!rdi->driver_f.schedule_send ||
+                           !rdi->driver_f.do_send)
+                               return -EINVAL;
+               break;
+
+       case POST_RECV:
+               check_driver_override(rdi, offsetof(struct ib_device,
+                                                   post_recv),
+                                     rvt_post_recv);
+               break;
+       case POST_SRQ_RECV:
+               check_driver_override(rdi, offsetof(struct ib_device,
+                                                   post_srq_recv),
+                                     rvt_post_srq_recv);
+               break;
+
+       case CREATE_AH:
+               check_driver_override(rdi, offsetof(struct ib_device,
+                                                   create_ah),
+                                     rvt_create_ah);
+               break;
+
+       case DESTROY_AH:
+               check_driver_override(rdi, offsetof(struct ib_device,
+                                                   destroy_ah),
+                                     rvt_destroy_ah);
+               break;
+
+       case MODIFY_AH:
+               check_driver_override(rdi, offsetof(struct ib_device,
+                                                   modify_ah),
+                                     rvt_modify_ah);
+               break;
+
+       case QUERY_AH:
+               check_driver_override(rdi, offsetof(struct ib_device,
+                                                   query_ah),
+                                     rvt_query_ah);
+               break;
+
+       case CREATE_SRQ:
+               check_driver_override(rdi, offsetof(struct ib_device,
+                                                   create_srq),
+                                     rvt_create_srq);
+               break;
+
+       case MODIFY_SRQ:
+               check_driver_override(rdi, offsetof(struct ib_device,
+                                                   modify_srq),
+                                     rvt_modify_srq);
+               break;
+
+       case DESTROY_SRQ:
+               check_driver_override(rdi, offsetof(struct ib_device,
+                                                   destroy_srq),
+                                     rvt_destroy_srq);
+               break;
+
+       case QUERY_SRQ:
+               check_driver_override(rdi, offsetof(struct ib_device,
+                                                   query_srq),
+                                     rvt_query_srq);
+               break;
+
+       case ATTACH_MCAST:
+               check_driver_override(rdi, offsetof(struct ib_device,
+                                                   attach_mcast),
+                                     rvt_attach_mcast);
+               break;
+
+       case DETACH_MCAST:
+               check_driver_override(rdi, offsetof(struct ib_device,
+                                                   detach_mcast),
+                                     rvt_detach_mcast);
+               break;
+
+       case GET_DMA_MR:
+               check_driver_override(rdi, offsetof(struct ib_device,
+                                                   get_dma_mr),
+                                     rvt_get_dma_mr);
+               break;
+
+       case REG_USER_MR:
+               check_driver_override(rdi, offsetof(struct ib_device,
+                                                   reg_user_mr),
+                                     rvt_reg_user_mr);
+               break;
+
+       case DEREG_MR:
+               check_driver_override(rdi, offsetof(struct ib_device,
+                                                   dereg_mr),
+                                     rvt_dereg_mr);
+               break;
+
+       case ALLOC_FMR:
+               check_driver_override(rdi, offsetof(struct ib_device,
+                                                   alloc_fmr),
+                                     rvt_alloc_fmr);
+               break;
+
+       case ALLOC_MR:
+               check_driver_override(rdi, offsetof(struct ib_device,
+                                                   alloc_mr),
+                                     rvt_alloc_mr);
+               break;
+
+       case MAP_PHYS_FMR:
+               check_driver_override(rdi, offsetof(struct ib_device,
+                                                   map_phys_fmr),
+                                     rvt_map_phys_fmr);
+               break;
+
+       case UNMAP_FMR:
+               check_driver_override(rdi, offsetof(struct ib_device,
+                                                   unmap_fmr),
+                                     rvt_unmap_fmr);
+               break;
+
+       case DEALLOC_FMR:
+               check_driver_override(rdi, offsetof(struct ib_device,
+                                                   dealloc_fmr),
+                                     rvt_dealloc_fmr);
+               break;
+
+       case MMAP:
+               check_driver_override(rdi, offsetof(struct ib_device,
+                                                   mmap),
+                                     rvt_mmap);
+               break;
+
+       case CREATE_CQ:
+               check_driver_override(rdi, offsetof(struct ib_device,
+                                                   create_cq),
+                                     rvt_create_cq);
+               break;
+
+       case DESTROY_CQ:
+               check_driver_override(rdi, offsetof(struct ib_device,
+                                                   destroy_cq),
+                                     rvt_destroy_cq);
+               break;
+
+       case POLL_CQ:
+               check_driver_override(rdi, offsetof(struct ib_device,
+                                                   poll_cq),
+                                     rvt_poll_cq);
+               break;
+
+       case REQ_NOTFIY_CQ:
+               check_driver_override(rdi, offsetof(struct ib_device,
+                                                   req_notify_cq),
+                                     rvt_req_notify_cq);
+               break;
+
+       case RESIZE_CQ:
+               check_driver_override(rdi, offsetof(struct ib_device,
+                                                   resize_cq),
+                                     rvt_resize_cq);
+               break;
+
+       case ALLOC_PD:
+               check_driver_override(rdi, offsetof(struct ib_device,
+                                                   alloc_pd),
+                                     rvt_alloc_pd);
+               break;
+
+       case DEALLOC_PD:
+               check_driver_override(rdi, offsetof(struct ib_device,
+                                                   dealloc_pd),
+                                     rvt_dealloc_pd);
+               break;
+
+       default:
+               return -EINVAL;
+       }
+
+       return 0;
+}
 
 /**
  * rvt_register_device - register a driver
@@ -343,35 +706,26 @@ static int rvt_get_port_immutable(struct ib_device *ibdev, u8 port_num,
  */
 int rvt_register_device(struct rvt_dev_info *rdi)
 {
-       /* Validate that drivers have provided the right information */
-       int ret = 0;
+       int ret = 0, i;
 
        if (!rdi)
                return -EINVAL;
 
-       if ((!rdi->driver_f.port_callback) ||
-           (!rdi->driver_f.get_card_name) ||
-           (!rdi->driver_f.get_pci_dev) ||
-           (!rdi->driver_f.check_ah)) {
-               pr_err("Driver not supporting req func\n");
-               return -EINVAL;
-       }
+       /*
+        * Check to ensure drivers have setup the required helpers for the verbs
+        * they want rdmavt to handle
+        */
+       for (i = 0; i < _VERB_IDX_MAX; i++)
+               if (check_support(rdi, i)) {
+                       pr_err("Driver support req not met at %d\n", i);
+                       return -EINVAL;
+               }
+
 
        /* Once we get past here we can use rvt_pr macros and tracepoints */
        trace_rvt_dbg(rdi, "Driver attempting registration");
        rvt_mmap_init(rdi);
 
-       /* Dev Ops */
-       CHECK_DRIVER_OVERRIDE(rdi, query_device);
-       CHECK_DRIVER_OVERRIDE(rdi, modify_device);
-       CHECK_DRIVER_OVERRIDE(rdi, query_port);
-       CHECK_DRIVER_OVERRIDE(rdi, modify_port);
-       CHECK_DRIVER_OVERRIDE(rdi, query_pkey);
-       CHECK_DRIVER_OVERRIDE(rdi, query_gid);
-       CHECK_DRIVER_OVERRIDE(rdi, alloc_ucontext);
-       CHECK_DRIVER_OVERRIDE(rdi, dealloc_ucontext);
-       CHECK_DRIVER_OVERRIDE(rdi, get_port_immutable);
-
        /* Queue Pairs */
        ret = rvt_driver_qp_init(rdi);
        if (ret) {
@@ -379,33 +733,15 @@ int rvt_register_device(struct rvt_dev_info *rdi)
                return -EINVAL;
        }
 
-       CHECK_DRIVER_OVERRIDE(rdi, create_qp);
-       CHECK_DRIVER_OVERRIDE(rdi, modify_qp);
-       CHECK_DRIVER_OVERRIDE(rdi, destroy_qp);
-       CHECK_DRIVER_OVERRIDE(rdi, query_qp);
-       CHECK_DRIVER_OVERRIDE(rdi, post_send);
-       CHECK_DRIVER_OVERRIDE(rdi, post_recv);
-       CHECK_DRIVER_OVERRIDE(rdi, post_srq_recv);
-
        /* Address Handle */
-       CHECK_DRIVER_OVERRIDE(rdi, create_ah);
-       CHECK_DRIVER_OVERRIDE(rdi, destroy_ah);
-       CHECK_DRIVER_OVERRIDE(rdi, modify_ah);
-       CHECK_DRIVER_OVERRIDE(rdi, query_ah);
        spin_lock_init(&rdi->n_ahs_lock);
        rdi->n_ahs_allocated = 0;
 
        /* Shared Receive Queue */
-       CHECK_DRIVER_OVERRIDE(rdi, create_srq);
-       CHECK_DRIVER_OVERRIDE(rdi, modify_srq);
-       CHECK_DRIVER_OVERRIDE(rdi, destroy_srq);
-       CHECK_DRIVER_OVERRIDE(rdi, query_srq);
        rvt_driver_srq_init(rdi);
 
        /* Multicast */
        rvt_driver_mcast_init(rdi);
-       CHECK_DRIVER_OVERRIDE(rdi, attach_mcast);
-       CHECK_DRIVER_OVERRIDE(rdi, detach_mcast);
 
        /* Mem Region */
        ret = rvt_driver_mr_init(rdi);
@@ -414,35 +750,18 @@ int rvt_register_device(struct rvt_dev_info *rdi)
                goto bail_no_mr;
        }
 
-       CHECK_DRIVER_OVERRIDE(rdi, get_dma_mr);
-       CHECK_DRIVER_OVERRIDE(rdi, reg_user_mr);
-       CHECK_DRIVER_OVERRIDE(rdi, dereg_mr);
-       CHECK_DRIVER_OVERRIDE(rdi, alloc_mr);
-       CHECK_DRIVER_OVERRIDE(rdi, alloc_fmr);
-       CHECK_DRIVER_OVERRIDE(rdi, map_phys_fmr);
-       CHECK_DRIVER_OVERRIDE(rdi, unmap_fmr);
-       CHECK_DRIVER_OVERRIDE(rdi, dealloc_fmr);
-       CHECK_DRIVER_OVERRIDE(rdi, mmap);
-
        /* Completion queues */
        ret = rvt_driver_cq_init(rdi);
        if (ret) {
                pr_err("Error in driver CQ init.\n");
                goto bail_mr;
        }
-       CHECK_DRIVER_OVERRIDE(rdi, create_cq);
-       CHECK_DRIVER_OVERRIDE(rdi, destroy_cq);
-       CHECK_DRIVER_OVERRIDE(rdi, poll_cq);
-       CHECK_DRIVER_OVERRIDE(rdi, req_notify_cq);
-       CHECK_DRIVER_OVERRIDE(rdi, resize_cq);
 
        /* DMA Operations */
        rdi->ibdev.dma_ops =
                rdi->ibdev.dma_ops ? : &rvt_default_dma_mapping_ops;
 
        /* Protection Domain */
-       CHECK_DRIVER_OVERRIDE(rdi, alloc_pd);
-       CHECK_DRIVER_OVERRIDE(rdi, dealloc_pd);
        spin_lock_init(&rdi->n_pds_lock);
        rdi->n_pds_allocated = 0;
 
index 57c708dddab407b45ca847c9bfe0187a07871802..ec658d8bf34e79fbcfcf42cf31c5c0eee42f03fe 100644 (file)
@@ -208,62 +208,157 @@ struct rvt_dev_info;
 struct rvt_swqe;
 struct rvt_driver_provided {
        /*
-        * The work to create port files in /sys/class Infiniband is different
-        * depending on the driver. This should not be extracted away and
-        * instead drivers are responsible for setting the correct callback for
-        * this.
+        * Which functions are required depends on which verbs rdmavt is
+        * providing and which verbs the driver is overriding. See
+        * check_support() for details.
         */
 
-       /* -------------------*/
-       /* Required functions */
-       /* -------------------*/
+       /* Passed to ib core registration. Callback to create syfs files */
        int (*port_callback)(struct ib_device *, u8, struct kobject *);
+
+       /*
+        * Returns a string to represent the device for which is being
+        * registered. This is primarily used for error and debug messages on
+        * the console.
+        */
        const char * (*get_card_name)(struct rvt_dev_info *rdi);
+
+       /*
+        * Returns a pointer to the undelying hardware's PCI device. This is
+        * used to display information as to what hardware is being referenced
+        * in an output message
+        */
        struct pci_dev * (*get_pci_dev)(struct rvt_dev_info *rdi);
-       unsigned (*free_all_qps)(struct rvt_dev_info *rdi);
+
+       /*
+        * Allocate a private queue pair data structure for driver specific
+        * information which is opaque to rdmavt.
+        */
        void * (*qp_priv_alloc)(struct rvt_dev_info *rdi, struct rvt_qp *qp,
                                gfp_t gfp);
+
+       /*
+        * Free the driver's private qp structure.
+        */
        void (*qp_priv_free)(struct rvt_dev_info *rdi, struct rvt_qp *qp);
+
+       /*
+        * Inform the driver the particular qp in quesiton has been reset so
+        * that it can clean up anything it needs to.
+        */
        void (*notify_qp_reset)(struct rvt_qp *qp);
+
+       /*
+        * Give the driver a notice that there is send work to do. It is up to
+        * the driver to generally push the packets out, this just queues the
+        * work with the driver. There are two variants here. The no_lock
+        * version requires the s_lock not to be held. The other assumes the
+        * s_lock is held.
+        */
        void (*schedule_send)(struct rvt_qp *qp);
        void (*schedule_send_no_lock)(struct rvt_qp *qp);
+
+       /*
+        * Sometimes rdmavt needs to kick the driver's send progress. That is
+        * done by this call back.
+        */
        void (*do_send)(struct rvt_qp *qp);
+
+       /*
+        * Get a path mtu from the driver based on qp attributes.
+        */
        int (*get_pmtu_from_attr)(struct rvt_dev_info *rdi, struct rvt_qp *qp,
                                  struct ib_qp_attr *attr);
+
+       /*
+        * Notify driver that it needs to flush any outstanding IO requests that
+        * are waiting on a qp.
+        */
        void (*flush_qp_waiters)(struct rvt_qp *qp);
+
+       /*
+        * Notify driver to stop its queue of sending packets. Nothing else
+        * should be posted to the queue pair after this has been called.
+        */
        void (*stop_send_queue)(struct rvt_qp *qp);
+
+       /*
+        * Have the drivr drain any in progress operations
+        */
        void (*quiesce_qp)(struct rvt_qp *qp);
+
+       /*
+        * Inform the driver a qp has went to error state.
+        */
        void (*notify_error_qp)(struct rvt_qp *qp);
+
+       /*
+        * Get an MTU for a qp.
+        */
        u32 (*mtu_from_qp)(struct rvt_dev_info *rdi, struct rvt_qp *qp,
                           u32 pmtu);
+       /*
+        * Convert an mtu to a path mtu
+        */
        int (*mtu_to_path_mtu)(u32 mtu);
+
+       /*
+        * Get the guid of a port in big endian byte order
+        */
        int (*get_guid_be)(struct rvt_dev_info *rdi, struct rvt_ibport *rvp,
                           int guid_index, __be64 *guid);
+
+       /*
+        * Query driver for the state of the port.
+        */
        int (*query_port_state)(struct rvt_dev_info *rdi, u8 port_num,
                                struct ib_port_attr *props);
+
+       /*
+        * Tell driver to shutdown a port
+        */
        int (*shut_down_port)(struct rvt_dev_info *rdi, u8 port_num);
+
+       /* Tell driver to send a trap for changed  port capabilities */
        void (*cap_mask_chg)(struct rvt_dev_info *rdi, u8 port_num);
 
-       /*--------------------*/
-       /* Optional functions */
-       /*--------------------*/
+       /*
+        * The following functions can be safely ignored completely. Any use of
+        * these is checked for NULL before blindly calling. Rdmavt should also
+        * be functional if drivers omit these.
+        */
+
+       /* Called to inform the driver that all qps should now be freed. */
+       unsigned (*free_all_qps)(struct rvt_dev_info *rdi);
+
+       /* Driver specific AH validation */
        int (*check_ah)(struct ib_device *, struct ib_ah_attr *);
+
+       /* Inform the driver a new AH has been created */
        void (*notify_new_ah)(struct ib_device *, struct ib_ah_attr *,
                              struct rvt_ah *);
+
+       /* Let the driver pick the next queue pair number*/
        int (*alloc_qpn)(struct rvt_dev_info *rdi, struct rvt_qpn_table *qpt,
                         enum ib_qp_type type, u8 port_num, gfp_t gfp);
-       /**
-        * Return 0 if modification is valid, -errno otherwise
-        */
+
+       /* Determine if its safe or allowed to modify the qp */
        int (*check_modify_qp)(struct rvt_qp *qp, struct ib_qp_attr *attr,
                               int attr_mask, struct ib_udata *udata);
+
+       /* Driver specific QP modification/notification-of */
        void (*modify_qp)(struct rvt_qp *qp, struct ib_qp_attr *attr,
                          int attr_mask, struct ib_udata *udata);
 
+       /* Driver specific work request checking */
        int (*check_send_wqe)(struct rvt_qp *qp, struct rvt_swqe *wqe);
 
+       /* Notify driver a mad agent has been created */
        void (*notify_create_mad_agent)(struct rvt_dev_info *rdi, int port_idx);
+
+       /* Notify driver a mad agent has been removed */
        void (*notify_free_mad_agent)(struct rvt_dev_info *rdi, int port_idx);
+
 };
 
 struct rvt_dev_info {