ide: IDE settings don't need an ide_lock held (1f473e9c) · Commits · 戴 / test

drivers/ide/ide-ioctls.c

+0 −3

Original line number	Diff line number	Diff line
		@@ -19,7 +19,6 @@ int ide_setting_ioctl(ide_drive_t drive, struct block_device bdev,
		const struct ide_ioctl_devset *s)
		{
		const struct ide_devset *ds;
		unsigned long flags;
		int err = -EOPNOTSUPP;

		for (; (ds = s->setting); s++) {
		@@ -33,9 +32,7 @@ int ide_setting_ioctl(ide_drive_t drive, struct block_device bdev,

		read_val:
		mutex_lock(&ide_setting_mtx);
		spin_lock_irqsave(&ide_lock, flags);
		err = ds->get(drive);
		spin_unlock_irqrestore(&ide_lock, flags);
		mutex_unlock(&ide_setting_mtx);
		return err >= 0 ? put_user(err, (long __user *)arg) : err;

+4 −21

Original line number	Diff line number	Diff line
		@@ -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);