diff options
Diffstat (limited to 'drivers/md/raid10.h')
| -rw-r--r-- | drivers/md/raid10.h | 150 |
1 files changed, 150 insertions, 0 deletions
diff --git a/drivers/md/raid10.h b/drivers/md/raid10.h new file mode 100644 index 00000000..7c615613 --- /dev/null +++ b/drivers/md/raid10.h @@ -0,0 +1,150 @@ +#ifndef _RAID10_H +#define _RAID10_H + +struct mirror_info { + struct md_rdev *rdev, *replacement; + sector_t head_position; + int recovery_disabled; /* matches + * mddev->recovery_disabled + * when we shouldn't try + * recovering this device. + */ +}; + +struct r10conf { + struct mddev *mddev; + struct mirror_info *mirrors; + int raid_disks; + spinlock_t device_lock; + + /* geometry */ + int near_copies; /* number of copies laid out + * raid0 style */ + int far_copies; /* number of copies laid 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. + */ + + sector_t dev_sectors; /* temp copy of + * mddev->dev_sectors */ + + 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; + int pending_count; + + 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. + */ + int have_replacement; /* There is at least one + * replacement device. + */ + wait_queue_head_t wait_barrier; + + mempool_t *r10bio_pool; + mempool_t *r10buf_pool; + struct page *tmppage; + + /* When taking over an array from a different personality, we store + * the new thread here until we fully activate the array. + */ + struct md_thread *thread; +}; + +/* + * 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 { + atomic_t remaining; /* 'have we finished' count, + * used from IRQ handlers + */ + sector_t sector; /* virtual sector number */ + int sectors; + unsigned long state; + struct mddev *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. + * We sometimes need an extra bio to write to the replacement. + */ + struct { + struct bio *bio; + union { + struct bio *repl_bio; /* used for resync and + * writes */ + struct md_rdev *rdev; /* used for reads + * (read_slot >= 0) */ + }; + 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) +/* When we successfully write to a known bad-block, we need to remove the + * bad-block marking which must be done from process context. So we record + * the success by setting devs[n].bio to IO_MADE_GOOD + */ +#define IO_MADE_GOOD ((struct bio *)2) + +#define BIO_SPECIAL(bio) ((unsigned long)bio <= 2) + +/* bits for r10bio.state */ +enum r10bio_state { + R10BIO_Uptodate, + R10BIO_IsSync, + R10BIO_IsRecover, + R10BIO_Degraded, +/* Set ReadError on bios that experience a read error + * so that raid10d knows what to do with them. + */ + R10BIO_ReadError, +/* If a write for this request means we can clear some + * known-bad-block records, we set this flag. + */ + R10BIO_MadeGood, + R10BIO_WriteError, +}; +#endif |