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, 121 insertions, 0 deletions

diff --git a/drivers/md/raid10.h b/drivers/md/raid10.h
new file mode 100644
index 00000000000..244dbe507a5
--- /dev/null
+++ b/drivers/md/raid10.h
@@ -0,0 +1,121 @@
+#ifndef _RAID10_H
+#define _RAID10_H
+
+typedef struct mirror_info mirror_info_t;
+
+struct mirror_info {
+	mdk_rdev_t	*rdev;
+	sector_t	head_position;
+};
+
+typedef struct r10bio_s r10bio_t;
+
+struct r10_private_data_s {
+	mddev_t			*mddev;
+	mirror_info_t		*mirrors;
+	int			raid_disks;
+	spinlock_t		device_lock;
+
+	/* geometry */
+	int			near_copies;  /* number of copies layed out raid0 style */
+	int 			far_copies;   /* number of copies layed out
+					       * at large strides across drives
+					       */
+	int			far_offset;   /* far_copies are offset by 1 stripe
+					       * instead of many
+					       */
+	int			copies;	      /* near_copies * far_copies.
+					       * must be <= raid_disks
+					       */
+	sector_t		stride;	      /* distance between far copies.
+					       * This is size / far_copies unless
+					       * far_offset, in which case it is
+					       * 1 stripe.
+					       */
+
+	int chunk_shift; /* shift from chunks to sectors */
+	sector_t chunk_mask;
+
+	struct list_head	retry_list;
+	/* queue pending writes and submit them on unplug */
+	struct bio_list		pending_bio_list;
+
+
+	spinlock_t		resync_lock;
+	int nr_pending;
+	int nr_waiting;
+	int nr_queued;
+	int barrier;
+	sector_t		next_resync;
+	int			fullsync;  /* set to 1 if a full sync is needed,
+					    * (fresh device added).
+					    * Cleared when a sync completes.
+					    */
+
+	wait_queue_head_t	wait_barrier;
+
+	mempool_t *r10bio_pool;
+	mempool_t *r10buf_pool;
+	struct page		*tmppage;
+};
+
+typedef struct r10_private_data_s 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) ((conf_t *) mddev->private)
+
+/*
+ * this is our 'private' RAID10 bio.
+ *
+ * it contains information about what kind of IO operations were started
+ * for this RAID10 operation, and about their status:
+ */
+
+struct r10bio_s {
+	atomic_t		remaining; /* 'have we finished' count,
+					    * used from IRQ handlers
+					    */
+	sector_t		sector;	/* virtual sector number */
+	int			sectors;
+	unsigned long		state;
+	mddev_t			*mddev;
+	/*
+	 * original bio going to /dev/mdx
+	 */
+	struct bio		*master_bio;
+	/*
+	 * if the IO is in READ direction, then this is where we read
+	 */
+	int			read_slot;
+
+	struct list_head	retry_list;
+	/*
+	 * if the IO is in WRITE direction, then multiple bios are used,
+	 * one for each copy.
+	 * When resyncing we also use one for each copy.
+	 * When reconstructing, we use 2 bios, one for read, one for write.
+	 * We choose the number when they are allocated.
+	 */
+	struct {
+		struct bio		*bio;
+		sector_t addr;
+		int devnum;
+	} devs[0];
+};
+
+/* when we get a read error on a read-only array, we redirect to another
+ * device without failing the first device, or trying to over-write to
+ * correct the read error.  To keep track of bad blocks on a per-bio
+ * level, we store IO_BLOCKED in the appropriate 'bios' pointer
+ */
+#define IO_BLOCKED ((struct bio*)1)
+
+/* bits for r10bio.state */
+#define	R10BIO_Uptodate	0
+#define	R10BIO_IsSync	1
+#define	R10BIO_IsRecover 2
+#define	R10BIO_Degraded 3
+#endif