From 395d8ef5bebe547a80737692f9789d2e36da16f2 Mon Sep 17 00:00:00 2001 From: Bartlomiej Zolnierkiewicz Date: Mon, 11 Feb 2008 00:32:14 +0100 Subject: ide-disk: fix flush requests (take 2) commit 813a0eb233ee67d7166241a8b389b6a76f2247f9 Author: Bartlomiej Zolnierkiewicz Date: Fri Jan 25 22:17:10 2008 +0100 ide: switch idedisk_prepare_flush() to use REQ_TYPE_ATA_TASKFILE requests ... broke flush requests. Allocating IDE command structure on the stack for flush requests is not a very brilliant idea: - idedisk_prepare_flush() only prepares the request and it doesn't wait for it to be completed - there are can be multiple flush requests queued in the queue Fix the problem (per hints from James Bottomley) by: - dynamically allocating ide_task_t instance using kmalloc(..., GFP_ATOMIC) - adding new taskfile flag (IDE_TFLAG_DYN) - calling kfree() in ide_end_drive_command() if IDE_TFLAG_DYN is set (while at it rename 'args' to 'task' and fix whitespace damage) [ This will be fixed properly before 2.6.25 but this bug is rather critical and the proper solution requires some more work + testing. ] Thanks to Sebastian Siewior and Christoph Hellwig for reporting the problem and testing patches (extra thanks to Sebastian for bisecting it to the guilty commmit). Tested-by: Sebastian Siewior Cc: Christoph Hellwig Cc: James Bottomley Cc: Jens Axboe Cc: Tejun Heo Cc: Sergei Shtylyov Signed-off-by: Bartlomiej Zolnierkiewicz --- drivers/ide/ide-io.c | 16 ++++++++++------ 1 file changed, 10 insertions(+), 6 deletions(-) (limited to 'drivers/ide/ide-io.c') diff --git a/drivers/ide/ide-io.c b/drivers/ide/ide-io.c index e41383fa3a5..715379605a7 100644 --- a/drivers/ide/ide-io.c +++ b/drivers/ide/ide-io.c @@ -361,17 +361,21 @@ void ide_end_drive_cmd (ide_drive_t *drive, u8 stat, u8 err) spin_unlock_irqrestore(&ide_lock, flags); if (rq->cmd_type == REQ_TYPE_ATA_TASKFILE) { - ide_task_t *args = (ide_task_t *) rq->special; + ide_task_t *task = (ide_task_t *)rq->special; + if (rq->errors == 0) - rq->errors = !OK_STAT(stat,READY_STAT,BAD_STAT); - - if (args) { - struct ide_taskfile *tf = &args->tf; + rq->errors = !OK_STAT(stat, READY_STAT, BAD_STAT); + + if (task) { + struct ide_taskfile *tf = &task->tf; tf->error = err; tf->status = stat; - ide_tf_read(drive, args); + ide_tf_read(drive, task); + + if (task->tf_flags & IDE_TFLAG_DYN) + kfree(task); } } else if (blk_pm_request(rq)) { struct request_pm_state *pm = rq->data; -- cgit v1.2.3-18-g5258