ide: add ide_device_{get,put}() helpers

* Add 'struct ide_host *host' field to ide_hwif_t and set it
  in ide_host_alloc_all().

* Add ide_device_{get,put}() helpers loosely based on SCSI's
  scsi_device_{get,put}() ones.

* Convert IDE device drivers to use ide_device_{get,put}().

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

1 files changed, 9 insertions, 3 deletions

diff --git a/drivers/ide/ide-disk.c b/drivers/ide/ide-disk.c
index df5fe5756871..28d85b410f7c 100644
--- a/drivers/ide/ide-disk.c
+++ b/drivers/ide/ide-disk.c
@@ -56,23 +56,29 @@ static DEFINE_MUTEX(idedisk_ref_mutex);
 #define ide_disk_g(disk) \
         container_of((disk)->private_data, struct ide_disk_obj, driver)
 
+static void ide_disk_release(struct kref *);
+
 static struct ide_disk_obj *ide_disk_get(struct gendisk *disk)
 {
         struct ide_disk_obj *idkp = NULL;
 
         mutex_lock(&idedisk_ref_mutex);
         idkp = ide_disk_g(disk);
-        if (idkp)
+        if (idkp) {
                 kref_get(&idkp->kref);
+                if (ide_device_get(idkp->drive)) {
+                        kref_put(&idkp->kref, ide_disk_release);
+                        idkp = NULL;
+                }
+        }
         mutex_unlock(&idedisk_ref_mutex);
         return idkp;
 }
 
-static void ide_disk_release(struct kref *);
-
 static void ide_disk_put(struct ide_disk_obj *idkp)
 {
         mutex_lock(&idedisk_ref_mutex);
+        ide_device_put(idkp->drive);
         kref_put(&idkp->kref, ide_disk_release);
         mutex_unlock(&idedisk_ref_mutex);
 }