drivers/net/netdevsim/sdev.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /* Copyright (c) 2019 Mellanox Technologies. All rights reserved */
   3
   4 #include <linux/debugfs.h>
   5 #include <linux/err.h>
   6 #include <linux/kernel.h>
   7 #include <linux/slab.h>
   8
   9 #include "netdevsim.h"
  10
  11 static struct dentry *nsim_sdev_ddir;
  12
  13 static u32 nsim_sdev_id;
  14
  15 struct netdevsim_shared_dev *nsim_sdev_get(struct netdevsim *joinns)
  16 {
  17         struct netdevsim_shared_dev *sdev;
  18         char sdev_ddir_name[10];
  19         int err;
  20
  21         if (joinns) {
  22                 if (WARN_ON(!joinns->sdev))
  23                         return ERR_PTR(-EINVAL);
  24                 sdev = joinns->sdev;
  25                 sdev->refcnt++;
  26                 return sdev;
  27         }
  28
  29         sdev = kzalloc(sizeof(*sdev), GFP_KERNEL);
  30         if (!sdev)
  31                 return ERR_PTR(-ENOMEM);
  32         sdev->refcnt = 1;
  33         sdev->switch_id = nsim_sdev_id++;
  34
  35         sprintf(sdev_ddir_name, "%u", sdev->switch_id);
  36         sdev->ddir = debugfs_create_dir(sdev_ddir_name, nsim_sdev_ddir);
  37         if (IS_ERR_OR_NULL(sdev->ddir)) {
  38                 err = PTR_ERR_OR_ZERO(sdev->ddir) ?: -EINVAL;
  39                 goto err_sdev_free;
  40         }
  41
  42         return sdev;
  43
  44 err_sdev_free:
  45         nsim_sdev_id--;
  46         kfree(sdev);
  47         return ERR_PTR(err);
  48 }
  49
  50 void nsim_sdev_put(struct netdevsim_shared_dev *sdev)
  51 {
  52         if (--sdev->refcnt)
  53                 return;
  54         debugfs_remove_recursive(sdev->ddir);
  55         kfree(sdev);
  56 }
  57
  58 int nsim_sdev_init(void)
  59 {
  60         nsim_sdev_ddir = debugfs_create_dir(DRV_NAME "_sdev", NULL);
  61         if (IS_ERR_OR_NULL(nsim_sdev_ddir))
  62                 return -ENOMEM;
  63         return 0;
  64 }
  65
  66 void nsim_sdev_exit(void)
  67 {
  68         debugfs_remove_recursive(nsim_sdev_ddir);
  69 }