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, 15 insertions, 24 deletions

diff --git a/drivers/acpi/processor_core.c b/drivers/acpi/processor_core.c
index a825b431b64f..dd28c912e84f 100644
--- a/drivers/acpi/processor_core.c
+++ b/drivers/acpi/processor_core.c
@@ -112,6 +112,7 @@ static struct acpi_driver acpi_processor_driver = {
 #define UNINSTALL_NOTIFY_HANDLER        2
 
 static const struct file_operations acpi_processor_info_fops = {
+        .owner = THIS_MODULE,
         .open = acpi_processor_info_open_fs,
         .read = seq_read,
         .llseek = seq_lseek,
@@ -326,40 +327,30 @@ static int acpi_processor_add_fs(struct acpi_device *device)
         acpi_device_dir(device)->owner = THIS_MODULE;
 
         /* 'info' [R] */
-        entry = create_proc_entry(ACPI_PROCESSOR_FILE_INFO,
-                                  S_IRUGO, acpi_device_dir(device));
+        entry = proc_create_data(ACPI_PROCESSOR_FILE_INFO,
+                                 S_IRUGO, acpi_device_dir(device),
+                                 &acpi_processor_info_fops,
+                                 acpi_driver_data(device));
         if (!entry)
                 return -EIO;
-        else {
-                entry->proc_fops = &acpi_processor_info_fops;
-                entry->data = acpi_driver_data(device);
-                entry->owner = THIS_MODULE;
-        }
 
         /* 'throttling' [R/W] */
-        entry = create_proc_entry(ACPI_PROCESSOR_FILE_THROTTLING,
-                                  S_IFREG | S_IRUGO | S_IWUSR,
-                                  acpi_device_dir(device));
+        entry = proc_create_data(ACPI_PROCESSOR_FILE_THROTTLING,
+                                 S_IFREG | S_IRUGO | S_IWUSR,
+                                 acpi_device_dir(device),
+                                 &acpi_processor_throttling_fops,
+                                 acpi_driver_data(device));
         if (!entry)
                 return -EIO;
-        else {
-                entry->proc_fops = &acpi_processor_throttling_fops;
-                entry->data = acpi_driver_data(device);
-                entry->owner = THIS_MODULE;
-        }
 
         /* 'limit' [R/W] */
-        entry = create_proc_entry(ACPI_PROCESSOR_FILE_LIMIT,
-                                  S_IFREG | S_IRUGO | S_IWUSR,
-                                  acpi_device_dir(device));
+        entry = proc_create_data(ACPI_PROCESSOR_FILE_LIMIT,
+                                 S_IFREG | S_IRUGO | S_IWUSR,
+                                 acpi_device_dir(device),
+                                 &acpi_processor_limit_fops,
+                                 acpi_driver_data(device));
         if (!entry)
                 return -EIO;
-        else {
-                entry->proc_fops = &acpi_processor_limit_fops;
-                entry->data = acpi_driver_data(device);
-                entry->owner = THIS_MODULE;
-        }
-
         return 0;
 }