Commit 75ddb38f authored by Tejun Heo's avatar Tejun Heo
Browse files

floppy: don't use PREPARE_[DELAYED_]WORK 



PREPARE_[DELAYED_]WORK() are being phased out.  They have few users
and a nasty surprise in terms of reentrancy guarantee as workqueue
considers work items to be different if they don't have the same work
function.

floppy has been multiplexing floppy_work and fd_timer with multiple
work functions.  Introduce floppy_work_workfn() and fd_timer_workfn()
which invoke floppy_work_fn and fd_timer_fn respectively and always
use the two functions as the work functions and update the users to
set floppy_work_fn and fd_timer_fn instead of overriding work
functions using PREPARE_[DELAYED_]WORK().

It would probably be best to route this with other related updates
through the workqueue tree.

Lightly tested using qemu.

Signed-off-by: default avatarTejun Heo <tj@kernel.org>
Acked-by: default avatarJiri Kosina <jkosina@suse.cz>
parent 4a8bb7f5

drivers/block/floppy.c

+28 −14
Original line number Diff line number Diff line
@@ -961,17 +961,31 @@ static void empty(void) 
{

}



static DECLARE_WORK(floppy_work, NULL);

static void (*floppy_work_fn)(void);



static void floppy_work_workfn(struct work_struct *work)

{

	floppy_work_fn();

}



static DECLARE_WORK(floppy_work, floppy_work_workfn);



static void schedule_bh(void (*handler)(void))

{

	WARN_ON(work_pending(&floppy_work));



	PREPARE_WORK(&floppy_work, (work_func_t)handler);

	floppy_work_fn = handler;

	queue_work(floppy_wq, &floppy_work);

}



static DECLARE_DELAYED_WORK(fd_timer, NULL);

static void (*fd_timer_fn)(void) = NULL;



static void fd_timer_workfn(struct work_struct *work)

{

	fd_timer_fn();

}



static DECLARE_DELAYED_WORK(fd_timer, fd_timer_workfn);



static void cancel_activity(void)

{
@@ -982,7 +996,7 @@ static void cancel_activity(void) 


/* this function makes sure that the disk stays in the drive during the

 * transfer */

static void fd_watchdog(struct work_struct *arg)

static void fd_watchdog(void)

{

	debug_dcl(DP->flags, "calling disk change from watchdog\n");
@@ -993,7 +1007,7 @@ static void fd_watchdog(struct work_struct *arg) 
		reset_fdc();

	} else {

		cancel_delayed_work(&fd_timer);

		PREPARE_DELAYED_WORK(&fd_timer, fd_watchdog);

		fd_timer_fn = fd_watchdog;

		queue_delayed_work(floppy_wq, &fd_timer, HZ / 10);

	}

}
@@ -1005,7 +1019,8 @@ static void main_command_interrupt(void) 
}



/* waits for a delay (spinup or select) to pass */

static int fd_wait_for_completion(unsigned long expires, work_func_t function)

static int fd_wait_for_completion(unsigned long expires,

				  void (*function)(void))

{

	if (FDCS->reset) {

		reset_fdc();	/* do the reset during sleep to win time
@@ -1016,7 +1031,7 @@ static int fd_wait_for_completion(unsigned long expires, work_func_t function) 


	if (time_before(jiffies, expires)) {

		cancel_delayed_work(&fd_timer);

		PREPARE_DELAYED_WORK(&fd_timer, function);

		fd_timer_fn = function;

		queue_delayed_work(floppy_wq, &fd_timer, expires - jiffies);

		return 1;

	}
@@ -1334,8 +1349,7 @@ static int fdc_dtr(void) 
	 * Pause 5 msec to avoid trouble. (Needs to be 2 jiffies)

	 */

	FDCS->dtr = raw_cmd->rate & 3;

	return fd_wait_for_completion(jiffies + 2UL * HZ / 100,

				      (work_func_t)floppy_ready);

	return fd_wait_for_completion(jiffies + 2UL * HZ / 100, floppy_ready);

}				/* fdc_dtr */



static void tell_sector(void)
@@ -1440,7 +1454,7 @@ static void setup_rw_floppy(void) 
	int flags;

	int dflags;

	unsigned long ready_date;

	work_func_t function;

	void (*function)(void);



	flags = raw_cmd->flags;

	if (flags & (FD_RAW_READ | FD_RAW_WRITE))
@@ -1454,9 +1468,9 @@ static void setup_rw_floppy(void) 
		 */

		if (time_after(ready_date, jiffies + DP->select_delay)) {

			ready_date -= DP->select_delay;

			function = (work_func_t)floppy_start;

			function = floppy_start;

		} else

			function = (work_func_t)setup_rw_floppy;

			function = setup_rw_floppy;



		/* wait until the floppy is spinning fast enough */

		if (fd_wait_for_completion(ready_date, function))
@@ -1486,7 +1500,7 @@ static void setup_rw_floppy(void) 
		inr = result();

		cont->interrupt();

	} else if (flags & FD_RAW_NEED_DISK)

		fd_watchdog(NULL);

		fd_watchdog();

}



static int blind_seek;
@@ -1863,7 +1877,7 @@ static int start_motor(void (*function)(void)) 


	/* wait_for_completion also schedules reset if needed. */

	return fd_wait_for_completion(DRS->select_date + DP->select_delay,

				      (work_func_t)function);

				      function);

}



static void floppy_ready(void)

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