summaryrefslogtreecommitdiff
path: root/drivers/md/raid10.h
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/md/raid10.h')
-rw-r--r--drivers/md/raid10.h121
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