create-ext4_feat-kobject-dynamically

   1 ext4: create ext4_feat kobject dynamically
   2
   3 From: Riccardo Schirone <sirmy15@gmail.com>
   4
   5 kobjects should always be allocated dynamically, because it is unknown
   6 to whoever creates them when kobjects can be released.
   7
   8 Signed-off-by: Riccardo Schirone <sirmy15@gmail.com>
   9 Signed-off-by: Theodore Ts'o <tytso@mit.edu>
  10 ---
  11  fs/ext4/sysfs.c | 33 ++++++++++++++++++++++-----------
  12  1 file changed, 22 insertions(+), 11 deletions(-)
  13
  14 diff --git a/fs/ext4/sysfs.c b/fs/ext4/sysfs.c
  15 index b096e157934f..c447f23cc876 100644
  16 --- a/fs/ext4/sysfs.c
  17 +++ b/fs/ext4/sysfs.c
  18 @@ -10,6 +10,7 @@
  19  #include <linux/time.h>
  20  #include <linux/fs.h>
  21  #include <linux/seq_file.h>
  22 +#include <linux/slab.h>
  23  #include <linux/proc_fs.h>
  24
  25  #include "ext4.h"
  26 @@ -350,11 +351,10 @@ static struct kset ext4_kset = {
  27  static struct kobj_type ext4_feat_ktype = {
  28         .default_attrs  = ext4_feat_attrs,
  29         .sysfs_ops      = &ext4_attr_ops,
  30 +       .release        = (void (*)(struct kobject *))kfree,
  31  };
  32
  33 -static struct kobject ext4_feat = {
  34 -       .kset   = &ext4_kset,
  35 -};
  36 +static struct kobject *ext4_feat;
  37
  38  #define PROC_FILE_SHOW_DEFN(name) \
  39  static int name##_open(struct inode *inode, struct file *file) \
  40 @@ -437,20 +437,31 @@ int __init ext4_init_sysfs(void)
  41                 return ret;
  42         }
  43
  44 -       ret = kobject_init_and_add(&ext4_feat, &ext4_feat_ktype,
  45 -                                  NULL, "features");
  46 -       if (ret) {
  47 -               kobject_put(&ext4_feat);
  48 -               kset_unregister(&ext4_kset);
  49 -       } else {
  50 -               ext4_proc_root = proc_mkdir(proc_dirname, NULL);
  51 +       ext4_feat = kzalloc(sizeof(*ext4_feat), GFP_KERNEL);
  52 +       if (!ext4_feat) {
  53 +               ret = -ENOMEM;
  54 +               goto kset_err;
  55         }
  56 +
  57 +       ext4_feat->kset = &ext4_kset;
  58 +       ret = kobject_init_and_add(ext4_feat, &ext4_feat_ktype,
  59 +                                  NULL, "features");
  60 +       if (ret)
  61 +               goto feat_err;
  62 +
  63 +       ext4_proc_root = proc_mkdir(proc_dirname, NULL);
  64 +       return ret;
  65 +
  66 +feat_err:
  67 +       kobject_put(ext4_feat);
  68 +kset_err:
  69 +       kset_unregister(&ext4_kset);
  70         return ret;
  71  }
  72
  73  void ext4_exit_sysfs(void)
  74  {
  75 -       kobject_put(&ext4_feat);
  76 +       kobject_put(ext4_feat);
  77         kset_unregister(&ext4_kset);
  78         remove_proc_entry(proc_dirname, NULL);
  79         ext4_proc_root = NULL;
  80 --
  81 2.14.3