ide: use lock bitops for ports serialization (v2)
* Add ->host_busy field to struct ide_host and use it's first bit
together with lock bitops to provide new ports serialization method.
* Convert core IDE code to use new ide_[un]lock_host() helpers.
This removes the need for taking hwgroup->lock if host is already
busy on serialized hosts and makes it possible to merge ide_hwgroup_t
into ide_hwif_t (done in the later patch).
* Remove no longer needed ide_hwgroup_t.busy and ide_[un]lock_hwgroup().
* Update do_ide_request() documentation.
v2:
* ide_release_lock() should be called inside IDE_HFLAG_SERIALIZE check.
* Add ide_hwif_t.busy flag and ide_[un]lock_port() for serializing
devices on a port.
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
diff --git a/include/linux/ide.h b/include/linux/ide.h
index 8b74ccd..00df155 100644
--- a/include/linux/ide.h
+++ b/include/linux/ide.h
@@ -828,6 +828,7 @@
unsigned present : 1; /* this interface exists */
unsigned sg_mapped : 1; /* sg_table and sg_nents are ready */
+ unsigned busy : 1; /* serializes devices on a port */
struct device gendev;
struct device *portdev;
@@ -851,8 +852,13 @@
unsigned long host_flags;
void *host_priv;
ide_hwif_t *cur_port; /* for hosts requiring serialization */
+
+ /* used for hosts requiring serialization */
+ volatile long host_busy;
};
+#define IDE_HOST_BUSY 0
+
/*
* internal ide interrupt handler type
*/
@@ -866,8 +872,6 @@
/* irq handler, if active */
ide_startstop_t (*handler)(ide_drive_t *);
- /* BOOL: protects all fields below */
- volatile int busy;
/* BOOL: polling active & poll_timeout field valid */
unsigned int polling : 1;
@@ -1271,26 +1275,6 @@
extern void ide_timer_expiry(unsigned long);
extern irqreturn_t ide_intr(int irq, void *dev_id);
-
-static inline int ide_lock_hwgroup(ide_hwgroup_t *hwgroup, ide_hwif_t *hwif)
-{
- if (hwgroup->busy)
- return 1;
-
- hwgroup->busy = 1;
- /* for atari only */
- ide_get_lock(ide_intr, hwif);
-
- return 0;
-}
-
-static inline void ide_unlock_hwgroup(ide_hwgroup_t *hwgroup)
-{
- /* for atari only */
- ide_release_lock();
- hwgroup->busy = 0;
-}
-
extern void do_ide_request(struct request_queue *);
void ide_init_disk(struct gendisk *, ide_drive_t *);
@@ -1617,13 +1601,6 @@
extern spinlock_t ide_lock;
extern struct mutex ide_cfg_mtx;
-/*
- * Structure locking:
- *
- * ide_hwgroup_t->busy: hwgroup->lock
- * ide_hwif_t->{hwgroup,mate}: constant, no locking
- * ide_drive_t->hwif: constant, no locking
- */
#define local_irq_set(flags) do { local_save_flags((flags)); local_irq_enable_in_hardirq(); } while (0)