acpi: use non-racy method for proc entries creation

Use proc_create()/proc_create_data() to make sure that ->proc_fops and ->data
be setup before gluing PDE to main tree.

Add correct ->owner to proc_fops to fix reading/module unloading race.

Signed-off-by: Denis V. Lunev <den@openvz.org>
Cc: Len Brown <lenb@kernel.org>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 4 insertions, 8 deletions

diff --git a/drivers/acpi/ac.c b/drivers/acpi/ac.c
index 43a95e5640de..5b73f6a2cd86 100644
--- a/drivers/acpi/ac.c
+++ b/drivers/acpi/ac.c
@@ -92,6 +92,7 @@ struct acpi_ac {
 
 #ifdef CONFIG_ACPI_PROCFS_POWER
 static const struct file_operations acpi_ac_fops = {
+        .owner = THIS_MODULE,
         .open = acpi_ac_open_fs,
         .read = seq_read,
         .llseek = seq_lseek,
@@ -195,16 +196,11 @@ static int acpi_ac_add_fs(struct acpi_device *device)
         }
 
         /* 'state' [R] */
-        entry = create_proc_entry(ACPI_AC_FILE_STATE,
-                                  S_IRUGO, acpi_device_dir(device));
+        entry = proc_create_data(ACPI_AC_FILE_STATE,
+                                 S_IRUGO, acpi_device_dir(device),
+                                 &acpi_ac_fops, acpi_driver_data(device));
         if (!entry)
                 return -ENODEV;
-        else {
-                entry->proc_fops = &acpi_ac_fops;
-                entry->data = acpi_driver_data(device);
-                entry->owner = THIS_MODULE;
-        }
-
         return 0;
 }