Commit 8b0c441e authored by Omar Sandoval's avatar Omar Sandoval Committed by Jens Axboe
Browse files

jsflash: stop sharing request queue across multiple gendisks 



Compile-tested only (by hacking it to compile on x86).

Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: default avatarOmar Sandoval <osandov@fb.com>
Signed-off-by: default avatarJens Axboe <axboe@fb.com>
parent 103db8b2

drivers/sbus/char/jsflash.c

+36 −14
Original line number Diff line number Diff line
@@ -183,11 +183,33 @@ static void jsfd_read(char *buf, unsigned long p, size_t togo) { 
	}

}



static void jsfd_do_request(struct request_queue *q)

static int jsfd_queue;



static struct request *jsfd_next_request(void)

{

	struct request_queue *q;

	struct request *rq;

	int old_pos = jsfd_queue;



	do {

		q = jsfd_disk[jsfd_queue]->queue;

		if (++jsfd_queue == JSF_MAX)

			jsfd_queue = 0;

		if (q) {

			rq = blk_fetch_request(q);

			if (rq)

				return rq;

		}

	} while (jsfd_queue != old_pos);



	return NULL;

}



static void jsfd_request(void)

{

	struct request *req;



	req = blk_fetch_request(q);

	req = jsfd_next_request();

	while (req) {

		struct jsfd_part *jdp = req->rq_disk->private_data;

		unsigned long offset = blk_rq_pos(req) << 9;
@@ -211,10 +233,15 @@ static void jsfd_do_request(struct request_queue *q) 
		err = 0;

	end:

		if (!__blk_end_request_cur(req, err))

			req = blk_fetch_request(q);

			req = jsfd_next_request();

	}

}



static void jsfd_do_request(struct request_queue *q)

{

	jsfd_request();

}



/*

 * The memory devices use the full 32/64 bits of the offset, and so we cannot

 * check against negative addresses: they are ok. The return value is weird,
@@ -544,8 +571,6 @@ static int jsflash_init(void) 
	return 0;

}



static struct request_queue *jsf_queue;



static int jsfd_init(void)

{

	static DEFINE_SPINLOCK(lock);
@@ -562,6 +587,11 @@ static int jsfd_init(void) 
		struct gendisk *disk = alloc_disk(1);

		if (!disk)

			goto out;

		disk->queue = blk_init_queue(jsfd_do_request, &lock);

		if (!disk->queue) {

			put_disk(disk);

			goto out;

		}

		jsfd_disk[i] = disk;

	}
@@ -570,13 +600,6 @@ static int jsfd_init(void) 
		goto out;

	}



	jsf_queue = blk_init_queue(jsfd_do_request, &lock);

	if (!jsf_queue) {

		err = -ENOMEM;

		unregister_blkdev(JSFD_MAJOR, "jsfd");

		goto out;

	}



	for (i = 0; i < JSF_MAX; i++) {

		struct gendisk *disk = jsfd_disk[i];

		if ((i & JSF_PART_MASK) >= JSF_NPART) continue;
@@ -589,7 +612,6 @@ static int jsfd_init(void) 
		disk->fops = &jsfd_fops;

		set_capacity(disk, jdp->dsize >> 9);

		disk->private_data = jdp;

		disk->queue = jsf_queue;

		add_disk(disk);

		set_disk_ro(disk, 1);

	}
@@ -619,6 +641,7 @@ static void __exit jsflash_cleanup_module(void) 
	for (i = 0; i < JSF_MAX; i++) {

		if ((i & JSF_PART_MASK) >= JSF_NPART) continue;

		del_gendisk(jsfd_disk[i]);

		blk_cleanup_queue(jsfd_disk[i]->queue);

		put_disk(jsfd_disk[i]);

	}

	if (jsf0.busy)
@@ -628,7 +651,6 @@ static void __exit jsflash_cleanup_module(void) 


	misc_deregister(&jsf_dev);

	unregister_blkdev(JSFD_MAJOR, "jsfd");

	blk_cleanup_queue(jsf_queue);

}



module_init(jsflash_init_module);