Re: [RFC] possible fix for broken floppy driver since 2.5.13

[Pavel Machek <pavel@ucw.cz>]

Hi!

> > I haven't got a clue on how to program Linux' block I/O interfaces.
> > Show me how to do a modern equivalent of getblk(dev,0,1024) + waiting
> > for the operation to complete and I'll update the patch ASAP.
> 
> I think something like the following should do it.
> (WARNING: entirely untested)

This looks pretty complicated... Maybe bread() is worth being put back
for 2.5?
								Pavel

> static void io_done(struct bio *bio)
> {
> 	complete((struct completion *)bio->bi_private);
> }
> 
> static int doio(struct block_device *bdev, size_t size)
> {
> 	struct completion comp;
> 	struct page * page;
> 	struct bio * bio;
> 
> 	bio = bio_alloc(GFP_KERNEL, 1);
> 	if (!bio)
> 		return -ENOMEM;
> 
> 	page = alloc_page(GFP_KERNEL);
> 	if (!page) {
> 		bio_put(bio);
> 		return -ENOMEM;
> 	}
> 
> 	bio->bi_sector = 0;
> 	bio->bi_bdev = bdev;
> 	bio->bi_io_vec[0].bv_page = page;
> 	bio->bi_io_vec[0].bv_len = size;
> 	bio->bi_io_vec[0].bv_offset = 0;
> 
> 	bio->bi_vcnt = 1;
> 	bio->bi_idx = 0;
> 	bio->bi_size = LOGPSIZE;
> 
> 	bio->bi_end_io = io_done;
> 	bio->bi_private = &complete;
> 
> 	submit_bio(READ, bio);
> 	run_task_queue(&tq_disk);
> 
> 	wait_for_completion(&comp);
> 
> 	bio_put(bio);
> 	__free_page(page);
> 
> 	return 0;
> }
> 
> -
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