ide: IDE settings don't need an ide_lock held

IDE settings are protected by ide_setting_mtx mutex so there is
no need to hold ide_lock in ide_setting_ioctl(), ide_read_setting()
and ide_proc_unregister_driver().

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

1 files changed, 4 insertions, 21 deletions

diff --git a/drivers/ide/ide-proc.c b/drivers/ide/ide-proc.c
index f3cddd1b2f8f..dd899e1f3841 100644
--- a/drivers/ide/ide-proc.c
+++ b/drivers/ide/ide-proc.c
@@ -155,13 +155,8 @@ static int ide_read_setting(ide_drive_t *drive,
         const struct ide_devset *ds = setting->setting;
         int val = -EINVAL;
 
-        if (ds->get) {
-                unsigned long flags;
-
-                spin_lock_irqsave(&ide_lock, flags);
+        if (ds->get)
                 val = ds->get(drive);
-                spin_unlock_irqrestore(&ide_lock, flags);
-        }
 
         return val;
 }
@@ -583,31 +578,19 @@ EXPORT_SYMBOL(ide_proc_register_driver);
  *      Clean up the driver specific /proc files and IDE settings
  *      for a given drive.
  *
- *      Takes ide_setting_mtx and ide_lock.
- *      Caller must hold none of the locks.
+ *      Takes ide_setting_mtx.
  */
 
 void ide_proc_unregister_driver(ide_drive_t *drive, ide_driver_t *driver)
 {
-        unsigned long flags;
-
         ide_remove_proc_entries(drive->proc, driver->proc_entries(drive));
 
         mutex_lock(&ide_setting_mtx);
-        spin_lock_irqsave(&ide_lock, flags);
         /*
-         * ide_setting_mtx protects the settings list
-         * ide_lock protects the use of settings
-         *
-         * so we need to hold both, ide_settings_sem because we want to
-         * modify the settings list, and ide_lock because we cannot take
-         * a setting out that is being used.
-         *
-         * OTOH both ide_{read,write}_setting are only ever used under
-         * ide_setting_mtx.
+         * ide_setting_mtx protects both the settings list and the use
+         * of settings (we cannot take a setting out that is being used).
          */
         drive->settings = NULL;
-        spin_unlock_irqrestore(&ide_lock, flags);
         mutex_unlock(&ide_setting_mtx);
 }
 EXPORT_SYMBOL(ide_proc_unregister_driver);