ide: use per-device request queue locks (v2)

* Move hack for flush requests from choose_drive() to do_ide_request().

* Add ide_plug_device() helper and convert core IDE code from using
  per-hwgroup lock as a request lock to use the ->queue_lock instead.

* Remove no longer needed:
  - choose_drive() function
  - WAKEUP() macro
  - 'sleeping' flag from ide_hwif_t
  - 'service_{start,time}' fields from ide_drive_t

This patch results in much simpler and more maintainable code
(besides being a scalability improvement).

v2:
* Fixes/improvements based on review from Elias:
  - take as many requests off the queue as possible
  - remove now redundant BUG_ON()

Cc: Elias Oltmanns <eo@nebensachen.de>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

1 files changed, 0 insertions, 4 deletions

diff --git a/include/linux/ide.h b/include/linux/ide.h
index f408d6123f1..5f86ad40ee7 100644
--- a/include/linux/ide.h
+++ b/include/linux/ide.h
@@ -603,8 +603,6 @@ struct ide_drive_s {
         unsigned long dev_flags;
 
         unsigned long sleep;            /* sleep until this time */
-        unsigned long service_start;    /* time we started last request */
-        unsigned long service_time;     /* service time of last request */
         unsigned long timeout;          /* max time to wait for irq */
 
         special_t       special;        /* special action flags */
@@ -872,8 +870,6 @@ typedef struct hwgroup_s {
 
                 /* BOOL: protects all fields below */
         volatile int busy;
-                /* BOOL: wake us up on timer expiry */
-        unsigned int sleeping   : 1;
                 /* BOOL: polling active & poll_timeout field valid */
         unsigned int polling    : 1;