Merge branch 'for-linus' of git://neil.brown.name/md

* 'for-linus' of git://neil.brown.name/md: (53 commits)
  md/raid5 revise rules for when to update metadata during reshape
  md/raid5: minor code cleanups in make_request.
  md: remove CONFIG_MD_RAID_RESHAPE config option.
  md/raid5: be more careful about write ordering when reshaping.
  md: don't display meaningless values in sysfs files resync_start and sync_speed
  md/raid5: allow layout and chunksize to be changed on active array.
  md/raid5: reshape using largest of old and new chunk size
  md/raid5: prepare for allowing reshape to change layout
  md/raid5: prepare for allowing reshape to change chunksize.
  md/raid5: clearly differentiate 'before' and 'after' stripes during reshape.
  Documentation/md.txt update
  md: allow number of drives in raid5 to be reduced
  md/raid5: change reshape-progress measurement to cope with reshaping backwards.
  md: add explicit method to signal the end of a reshape.
  md/raid5: enhance raid5_size to work correctly with negative delta_disks
  md/raid5: drop qd_idx from r6_state
  md/raid6: move raid6 data processing to raid6_pq.ko
  md: raid5 run(): Fix max_degraded for raid level 4.
  md: 'array_size' sysfs attribute
  md: centralize ->array_sectors modifications
  ...

1 files changed, 40 insertions, 0 deletions

diff --git a/drivers/md/multipath.h b/drivers/md/multipath.h
new file mode 100644
index 000000000000..6fa70b400cda
--- /dev/null
+++ b/drivers/md/multipath.h
@@ -0,0 +1,40 @@
+#ifndef _MULTIPATH_H
+#define _MULTIPATH_H
+
+struct multipath_info {
+        mdk_rdev_t      *rdev;
+};
+
+struct multipath_private_data {
+        mddev_t                 *mddev;
+        struct multipath_info   *multipaths;
+        int                     raid_disks;
+        int                     working_disks;
+        spinlock_t              device_lock;
+        struct list_head        retry_list;
+
+        mempool_t               *pool;
+};
+
+typedef struct multipath_private_data multipath_conf_t;
+
+/*
+ * this is the only point in the RAID code where we violate
+ * C type safety. mddev->private is an 'opaque' pointer.
+ */
+#define mddev_to_conf(mddev) ((multipath_conf_t *) mddev->private)
+
+/*
+ * this is our 'private' 'collective' MULTIPATH buffer head.
+ * it contains information about what kind of IO operations were started
+ * for this MULTIPATH operation, and about their status:
+ */
+
+struct multipath_bh {
+        mddev_t                 *mddev;
+        struct bio              *master_bio;
+        struct bio              bio;
+        int                     path;
+        struct list_head        retry_list;
+};
+#endif