parport/pf: stop sharing request queue across multiple gendisks
Compile-tested only.
Cc: Tim Waugh <tim@cyberelk.net>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
diff --git a/drivers/block/paride/pf.c b/drivers/block/paride/pf.c
index 14c5d32..f24ca73 100644
--- a/drivers/block/paride/pf.c
+++ b/drivers/block/paride/pf.c
@@ -287,6 +287,12 @@
struct gendisk *disk = alloc_disk(1);
if (!disk)
continue;
+ disk->queue = blk_init_queue(do_pf_request, &pf_spin_lock);
+ if (!disk->queue) {
+ put_disk(disk);
+ return;
+ }
+ blk_queue_max_segments(disk->queue, cluster);
pf->disk = disk;
pf->pi = &pf->pia;
pf->media_status = PF_NM;
@@ -772,7 +778,28 @@
return (((status_reg(pf_current) & (STAT_BUSY | pf_mask)) == pf_mask));
}
-static struct request_queue *pf_queue;
+static int pf_queue;
+
+static int set_next_request(void)
+{
+ struct pf_unit *pf;
+ struct request_queue *q;
+ int old_pos = pf_queue;
+
+ do {
+ pf = &units[pf_queue];
+ q = pf->present ? pf->disk->queue : NULL;
+ if (++pf_queue == PF_UNITS)
+ pf_queue = 0;
+ if (q) {
+ pf_req = blk_fetch_request(q);
+ if (pf_req)
+ break;
+ }
+ } while (pf_queue != old_pos);
+
+ return pf_req != NULL;
+}
static void pf_end_request(int err)
{
@@ -780,16 +807,13 @@
pf_req = NULL;
}
-static void do_pf_request(struct request_queue * q)
+static void pf_request(void)
{
if (pf_busy)
return;
repeat:
- if (!pf_req) {
- pf_req = blk_fetch_request(q);
- if (!pf_req)
- return;
- }
+ if (!pf_req && !set_next_request())
+ return;
pf_current = pf_req->rq_disk->private_data;
pf_block = blk_rq_pos(pf_req);
@@ -817,6 +841,11 @@
}
}
+static void do_pf_request(struct request_queue *q)
+{
+ pf_request();
+}
+
static int pf_next_buf(void)
{
unsigned long saved_flags;
@@ -846,7 +875,7 @@
spin_lock_irqsave(&pf_spin_lock, saved_flags);
pf_end_request(err);
pf_busy = 0;
- do_pf_request(pf_queue);
+ pf_request();
spin_unlock_irqrestore(&pf_spin_lock, saved_flags);
}
@@ -972,15 +1001,6 @@
put_disk(pf->disk);
return -EBUSY;
}
- pf_queue = blk_init_queue(do_pf_request, &pf_spin_lock);
- if (!pf_queue) {
- unregister_blkdev(major, name);
- for (pf = units, unit = 0; unit < PF_UNITS; pf++, unit++)
- put_disk(pf->disk);
- return -ENOMEM;
- }
-
- blk_queue_max_segments(pf_queue, cluster);
for (pf = units, unit = 0; unit < PF_UNITS; pf++, unit++) {
struct gendisk *disk = pf->disk;
@@ -988,7 +1008,6 @@
if (!pf->present)
continue;
disk->private_data = pf;
- disk->queue = pf_queue;
add_disk(disk);
}
return 0;
@@ -1003,10 +1022,10 @@
if (!pf->present)
continue;
del_gendisk(pf->disk);
+ blk_cleanup_queue(pf->disk->queue);
put_disk(pf->disk);
pi_release(pf->pi);
}
- blk_cleanup_queue(pf_queue);
}
MODULE_LICENSE("GPL");