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  */
  20 enum 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
  52 struct rdma_restrack_entry;
  53
  54 /**
  55  * struct rdma_restrack_root - main resource tracking management
  56  * entity, per-device
  57  */
  58 struct 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  */
  79 struct 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  */
 129 void rdma_restrack_init(struct rdma_restrack_root *res);
 130
 131 /**
 132  * rdma_restrack_clean() - clean resource tracking
 133  * @res:  resource tracking root
 134  */
 135 void 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  */
 143 int rdma_restrack_count(struct rdma_restrack_root *res,
 144                         enum rdma_restrack_type type,
 145                         struct pid_namespace *ns);
 146
 147 void rdma_restrack_kadd(struct rdma_restrack_entry *res);
 148 void 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  */
 155 void 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  */
 161 static 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  */
 170 int __must_check rdma_restrack_get(struct rdma_restrack_entry *res);
 171
 172 /**
 173  * rdma_restrack_put() - release resource
 174  * @res:  resource entry
 175  */
 176 int 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  */
 183 void 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  */
 190 int rdma_nl_put_driver_u32(struct sk_buff *msg, const char *name, u32 value);
 191 int rdma_nl_put_driver_u32_hex(struct sk_buff *msg, const char *name,
 192                                u32 value);
 193 int rdma_nl_put_driver_u64(struct sk_buff *msg, const char *name, u64 value);
 194 int rdma_nl_put_driver_u64_hex(struct sk_buff *msg, const char *name,
 195                                u64 value);
 196 #endif /* _RDMA_RESTRACK_H_ */