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_MAX: Last entry, used for array dclarations
  43         */
  44        RDMA_RESTRACK_MAX
  45};
  46
  47#define RDMA_RESTRACK_HASH_BITS 8
  48struct rdma_restrack_entry;
  49
  50/**
  51 * struct rdma_restrack_root - main resource tracking management
  52 * entity, per-device
  53 */
  54struct rdma_restrack_root {
  55        /*
  56         * @rwsem: Read/write lock to protect lists
  57         */
  58        struct rw_semaphore     rwsem;
  59        /**
  60         * @hash: global database for all resources per-device
  61         */
  62        DECLARE_HASHTABLE(hash, RDMA_RESTRACK_HASH_BITS);
  63        /**
  64         * @fill_res_entry: driver-specific fill function
  65         *
  66         * Allows rdma drivers to add their own restrack attributes.
  67         */
  68        int (*fill_res_entry)(struct sk_buff *msg,
  69                              struct rdma_restrack_entry *entry);
  70};
  71
  72/**
  73 * struct rdma_restrack_entry - metadata per-entry
  74 */
  75struct rdma_restrack_entry {
  76        /**
  77         * @valid: validity indicator
  78         *
  79         * The entries are filled during rdma_restrack_add,
  80         * can be attempted to be free during rdma_restrack_del.
  81         *
  82         * As an example for that, see mlx5 QPs with type MLX5_IB_QPT_HW_GSI
  83         */
  84        bool                    valid;
  85        /*
  86         * @kref: Protect destroy of the resource
  87         */
  88        struct kref             kref;
  89        /*
  90         * @comp: Signal that all consumers of resource are completed their work
  91         */
  92        struct completion       comp;
  93        /**
  94         * @task: owner of resource tracking entity
  95         *
  96         * There are two types of entities: created by user and created
  97         * by kernel.
  98         *
  99         * This is relevant for the entities created by users.
 100         * For the entities created by kernel, this pointer will be NULL.
 101         */
 102        struct task_struct      *task;
 103        /**
 104         * @kern_name: name of owner for the kernel created entities.
 105         */
 106        const char              *kern_name;
 107        /**
 108         * @node: hash table entry
 109         */
 110        struct hlist_node       node;
 111        /**
 112         * @type: various objects in restrack database
 113         */
 114        enum rdma_restrack_type type;
 115};
 116
 117/**
 118 * rdma_restrack_init() - initialize resource tracking
 119 * @res:  resource tracking root
 120 */
 121void rdma_restrack_init(struct rdma_restrack_root *res);
 122
 123/**
 124 * rdma_restrack_clean() - clean resource tracking
 125 * @res:  resource tracking root
 126 */
 127void rdma_restrack_clean(struct rdma_restrack_root *res);
 128
 129/**
 130 * rdma_restrack_count() - the current usage of specific object
 131 * @res:  resource entry
 132 * @type: actual type of object to operate
 133 * @ns:   PID namespace
 134 */
 135int rdma_restrack_count(struct rdma_restrack_root *res,
 136                        enum rdma_restrack_type type,
 137                        struct pid_namespace *ns);
 138
 139/**
 140 * rdma_restrack_add() - add object to the reource tracking database
 141 * @res:  resource entry
 142 */
 143void rdma_restrack_add(struct rdma_restrack_entry *res);
 144
 145/**
 146 * rdma_restrack_del() - delete object from the reource tracking database
 147 * @res:  resource entry
 148 * @type: actual type of object to operate
 149 */
 150void rdma_restrack_del(struct rdma_restrack_entry *res);
 151
 152/**
 153 * rdma_is_kernel_res() - check the owner of resource
 154 * @res:  resource entry
 155 */
 156static inline bool rdma_is_kernel_res(struct rdma_restrack_entry *res)
 157{
 158        return !res->task;
 159}
 160
 161/**
 162 * rdma_restrack_get() - grab to protect resource from release
 163 * @res:  resource entry
 164 */
 165int __must_check rdma_restrack_get(struct rdma_restrack_entry *res);
 166
 167/**
 168 * rdma_restrack_put() - release resource
 169 * @res:  resource entry
 170 */
 171int rdma_restrack_put(struct rdma_restrack_entry *res);
 172
 173/**
 174 * rdma_restrack_set_task() - set the task for this resource
 175 * @res:  resource entry
 176 * @caller: kernel name, the current task will be used if the caller is NULL.
 177 */
 178void rdma_restrack_set_task(struct rdma_restrack_entry *res,
 179                            const char *caller);
 180
 181/*
 182 * Helper functions for rdma drivers when filling out
 183 * nldev driver attributes.
 184 */
 185int rdma_nl_put_driver_u32(struct sk_buff *msg, const char *name, u32 value);
 186int rdma_nl_put_driver_u32_hex(struct sk_buff *msg, const char *name,
 187                               u32 value);
 188int rdma_nl_put_driver_u64(struct sk_buff *msg, const char *name, u64 value);
 189int rdma_nl_put_driver_u64_hex(struct sk_buff *msg, const char *name,
 190                               u64 value);
 191#endif /* _RDMA_RESTRACK_H_ */
 192