LXR linux/include/rdma/restrack.h

   1/* SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB */
   2/*
   3 * Copyright (c) 2017-2018 Mellanox Technologies. All rights reserved.
   4 */
   5
   6#ifndef _RDMA_RESTRACK_H_
   7#define _RDMA_RESTRACK_H_
   8
   9#include <linux/typecheck.h>
  10#include <linux/rwsem.h>
  11#include <linux/sched.h>
  12#include <linux/kref.h>
  13#include <linux/completion.h>
  14#include <linux/sched/task.h>
  15#include <uapi/rdma/rdma_netlink.h>
  16
  17/**
  18 * enum rdma_restrack_type - HW objects to track
  19 */
  20enum rdma_restrack_type {
  21        /**
  22         * @RDMA_RESTRACK_PD: Protection domain (PD)
  23         */
  24        RDMA_RESTRACK_PD,
  25        /**
  26         * @RDMA_RESTRACK_CQ: Completion queue (CQ)
  27         */
  28        RDMA_RESTRACK_CQ,
  29        /**
  30         * @RDMA_RESTRACK_QP: Queue pair (QP)
  31         */
  32        RDMA_RESTRACK_QP,
  33        /**
  34         * @RDMA_RESTRACK_CM_ID: Connection Manager ID (CM_ID)
  35         */
  36        RDMA_RESTRACK_CM_ID,
  37        /**
  38         * @RDMA_RESTRACK_MR: Memory Region (MR)
  39         */
  40        RDMA_RESTRACK_MR,
  41        /**
  42         * @RDMA_RESTRACK_CTX: Verbs contexts (CTX)
  43         */
  44        RDMA_RESTRACK_CTX,
  45        /**
  46         * @RDMA_RESTRACK_MAX: Last entry, used for array dclarations
  47         */
  48        RDMA_RESTRACK_MAX
  49};
  50
  51#define RDMA_RESTRACK_HASH_BITS 8
  52struct rdma_restrack_entry;
  53
  54/**
  55 * struct rdma_restrack_root - main resource tracking management
  56 * entity, per-device
  57 */
  58struct rdma_restrack_root {
  59        /*
  60         * @rwsem: Read/write lock to protect lists
  61         */
  62        struct rw_semaphore     rwsem;
  63        /**
  64         * @hash: global database for all resources per-device
  65         */
  66        DECLARE_HASHTABLE(hash, RDMA_RESTRACK_HASH_BITS);
  67        /**
  68         * @fill_res_entry: driver-specific fill function
  69         *
  70         * Allows rdma drivers to add their own restrack attributes.
  71         */
  72        int (*fill_res_entry)(struct sk_buff *msg,
  73                              struct rdma_restrack_entry *entry);
  74};
  75
  76/**
  77 * struct rdma_restrack_entry - metadata per-entry
  78 */
  79struct rdma_restrack_entry {
  80        /**
  81         * @valid: validity indicator
  82         *
  83         * The entries are filled during rdma_restrack_add,
  84         * can be attempted to be free during rdma_restrack_del.
  85         *
  86         * As an example for that, see mlx5 QPs with type MLX5_IB_QPT_HW_GSI
  87         */
  88        bool                    valid;
  89        /*
  90         * @kref: Protect destroy of the resource
  91         */
  92        struct kref             kref;
  93        /*
  94         * @comp: Signal that all consumers of resource are completed their work
  95         */
  96        struct completion       comp;
  97        /**
  98         * @task: owner of resource tracking entity
  99         *
 100         * There are two types of entities: created by user and created
 101         * by kernel.
 102         *
 103         * This is relevant for the entities created by users.
 104         * For the entities created by kernel, this pointer will be NULL.
 105         */
 106        struct task_struct      *task;
 107        /**
 108         * @kern_name: name of owner for the kernel created entities.
 109         */
 110        const char              *kern_name;
 111        /**
 112         * @node: hash table entry
 113         */
 114        struct hlist_node       node;
 115        /**
 116         * @type: various objects in restrack database
 117         */
 118        enum rdma_restrack_type type;
 119        /**
 120         * @user: user resource
 121         */
 122        bool                    user;
 123};
 124
 125/**
 126 * rdma_restrack_init() - initialize resource tracking
 127 * @res:  resource tracking root
 128 */
 129void rdma_restrack_init(struct rdma_restrack_root *res);
 130
 131/**
 132 * rdma_restrack_clean() - clean resource tracking
 133 * @res:  resource tracking root
 134 */
 135void rdma_restrack_clean(struct rdma_restrack_root *res);
 136
 137/**
 138 * rdma_restrack_count() - the current usage of specific object
 139 * @res:  resource entry
 140 * @type: actual type of object to operate
 141 * @ns:   PID namespace
 142 */
 143int rdma_restrack_count(struct rdma_restrack_root *res,
 144                        enum rdma_restrack_type type,
 145                        struct pid_namespace *ns);
 146
 147void rdma_restrack_kadd(struct rdma_restrack_entry *res);
 148void rdma_restrack_uadd(struct rdma_restrack_entry *res);
 149
 150/**
 151 * rdma_restrack_del() - delete object from the reource tracking database
 152 * @res:  resource entry
 153 * @type: actual type of object to operate
 154 */
 155void rdma_restrack_del(struct rdma_restrack_entry *res);
 156
 157/**
 158 * rdma_is_kernel_res() - check the owner of resource
 159 * @res:  resource entry
 160 */
 161static inline bool rdma_is_kernel_res(struct rdma_restrack_entry *res)
 162{
 163        return !res->user;
 164}
 165
 166/**
 167 * rdma_restrack_get() - grab to protect resource from release
 168 * @res:  resource entry
 169 */
 170int __must_check rdma_restrack_get(struct rdma_restrack_entry *res);
 171
 172/**
 173 * rdma_restrack_put() - release resource
 174 * @res:  resource entry
 175 */
 176int rdma_restrack_put(struct rdma_restrack_entry *res);
 177
 178/**
 179 * rdma_restrack_set_task() - set the task for this resource
 180 * @res:  resource entry
 181 * @caller: kernel name, the current task will be used if the caller is NULL.
 182 */
 183void rdma_restrack_set_task(struct rdma_restrack_entry *res,
 184                            const char *caller);
 185
 186/*
 187 * Helper functions for rdma drivers when filling out
 188 * nldev driver attributes.
 189 */
 190int rdma_nl_put_driver_u32(struct sk_buff *msg, const char *name, u32 value);
 191int rdma_nl_put_driver_u32_hex(struct sk_buff *msg, const char *name,
 192                               u32 value);
 193int rdma_nl_put_driver_u64(struct sk_buff *msg, const char *name, u64 value);
 194int rdma_nl_put_driver_u64_hex(struct sk_buff *msg, const char *name,
 195                               u64 value);
 196#endif /* _RDMA_RESTRACK_H_ */
 197