aboutsummaryrefslogtreecommitdiff
path: root/drivers/md/raid1.h
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/md/raid1.h')
-rw-r--r--drivers/md/raid1.h132
1 files changed, 132 insertions, 0 deletions
diff --git a/drivers/md/raid1.h b/drivers/md/raid1.h
new file mode 100644
index 00000000000..1620eea3d57
--- /dev/null
+++ b/drivers/md/raid1.h
@@ -0,0 +1,132 @@
+#ifndef _RAID1_H
+#define _RAID1_H
+
+typedef struct mirror_info mirror_info_t;
+
+struct mirror_info {
+ mdk_rdev_t *rdev;
+ sector_t head_position;
+};
+
+/*
+ * memory pools need a pointer to the mddev, so they can force an unplug
+ * when memory is tight, and a count of the number of drives that the
+ * pool was allocated for, so they know how much to allocate and free.
+ * mddev->raid_disks cannot be used, as it can change while a pool is active
+ * These two datums are stored in a kmalloced struct.
+ */
+
+struct pool_info {
+ mddev_t *mddev;
+ int raid_disks;
+};
+
+
+typedef struct r1bio_s r1bio_t;
+
+struct r1_private_data_s {
+ mddev_t *mddev;
+ mirror_info_t *mirrors;
+ int raid_disks;
+ int last_used;
+ sector_t next_seq_sect;
+ spinlock_t device_lock;
+
+ struct list_head retry_list;
+ /* queue pending writes and submit them on unplug */
+ struct bio_list pending_bio_list;
+ /* queue of writes that have been unplugged */
+ struct bio_list flushing_bio_list;
+
+ /* for use when syncing mirrors: */
+
+ 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;
+
+ struct pool_info *poolinfo;
+
+ struct page *tmppage;
+
+ mempool_t *r1bio_pool;
+ mempool_t *r1buf_pool;
+};
+
+typedef struct r1_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' RAID1 bio.
+ *
+ * it contains information about what kind of IO operations were started
+ * for this RAID1 operation, and about their status:
+ */
+
+struct r1bio_s {
+ atomic_t remaining; /* 'have we finished' count,
+ * used from IRQ handlers
+ */
+ atomic_t behind_remaining; /* number of write-behind ios remaining
+ * in this BehindIO request
+ */
+ sector_t sector;
+ 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_disk;
+
+ struct list_head retry_list;
+ struct bitmap_update *bitmap_update;
+ /*
+ * if the IO is in WRITE direction, then multiple bios are used.
+ * We choose the number when they are allocated.
+ */
+ struct bio *bios[0];
+ /* DO NOT PUT ANY NEW FIELDS HERE - bios array is contiguously alloced*/
+};
+
+/* 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 r1bio.state */
+#define R1BIO_Uptodate 0
+#define R1BIO_IsSync 1
+#define R1BIO_Degraded 2
+#define R1BIO_BehindIO 3
+#define R1BIO_Barrier 4
+#define R1BIO_BarrierRetry 5
+/* For write-behind requests, we call bi_end_io when
+ * the last non-write-behind device completes, providing
+ * any write was successful. Otherwise we call when
+ * any write-behind write succeeds, otherwise we call
+ * with failure when last write completes (and all failed).
+ * Record that bi_end_io was called with this flag...
+ */
+#define R1BIO_Returned 6
+
+#endif