1 #ifndef _RAID10_H 2 #define _RAID10_H 3 4 struct mirror_info { 5 struct md_rdev *rdev; 6 sector_t head_position; 7 int recovery_disabled; /* matches 8 * mddev->recovery_disabled 9 * when we shouldn't try 10 * recovering this device. 11 */ 12 }; 13 14 struct r10conf { 15 struct mddev *mddev; 16 struct mirror_info *mirrors; 17 int raid_disks; 18 spinlock_t device_lock; 19 20 /* geometry */ 21 int near_copies; /* number of copies laid out raid0 style */ 22 int far_copies; /* number of copies laid out 23 * at large strides across drives 24 */ 25 int far_offset; /* far_copies are offset by 1 stripe 26 * instead of many 27 */ 28 int copies; /* near_copies * far_copies. 29 * must be <= raid_disks 30 */ 31 sector_t stride; /* distance between far copies. 32 * This is size / far_copies unless 33 * far_offset, in which case it is 34 * 1 stripe. 35 */ 36 37 sector_t dev_sectors; /* temp copy of mddev->dev_sectors */ 38 39 int chunk_shift; /* shift from chunks to sectors */ 40 sector_t chunk_mask; 41 42 struct list_head retry_list; 43 /* queue pending writes and submit them on unplug */ 44 struct bio_list pending_bio_list; 45 int pending_count; 46 47 spinlock_t resync_lock; 48 int nr_pending; 49 int nr_waiting; 50 int nr_queued; 51 int barrier; 52 sector_t next_resync; 53 int fullsync; /* set to 1 if a full sync is needed, 54 * (fresh device added). 55 * Cleared when a sync completes. 56 */ 57 58 wait_queue_head_t wait_barrier; 59 60 mempool_t *r10bio_pool; 61 mempool_t *r10buf_pool; 62 struct page *tmppage; 63 64 /* When taking over an array from a different personality, we store 65 * the new thread here until we fully activate the array. 66 */ 67 struct md_thread *thread; 68 }; 69 70 /* 71 * this is our 'private' RAID10 bio. 72 * 73 * it contains information about what kind of IO operations were started 74 * for this RAID10 operation, and about their status: 75 */ 76 77 struct r10bio { 78 atomic_t remaining; /* 'have we finished' count, 79 * used from IRQ handlers 80 */ 81 sector_t sector; /* virtual sector number */ 82 int sectors; 83 unsigned long state; 84 struct mddev *mddev; 85 /* 86 * original bio going to /dev/mdx 87 */ 88 struct bio *master_bio; 89 /* 90 * if the IO is in READ direction, then this is where we read 91 */ 92 int read_slot; 93 94 struct list_head retry_list; 95 /* 96 * if the IO is in WRITE direction, then multiple bios are used, 97 * one for each copy. 98 * When resyncing we also use one for each copy. 99 * When reconstructing, we use 2 bios, one for read, one for write. 100 * We choose the number when they are allocated. 101 */ 102 struct { 103 struct bio *bio; 104 sector_t addr; 105 int devnum; 106 } devs[0]; 107 }; 108 109 /* when we get a read error on a read-only array, we redirect to another 110 * device without failing the first device, or trying to over-write to 111 * correct the read error. To keep track of bad blocks on a per-bio 112 * level, we store IO_BLOCKED in the appropriate 'bios' pointer 113 */ 114 #define IO_BLOCKED ((struct bio*)1) 115 /* When we successfully write to a known bad-block, we need to remove the 116 * bad-block marking which must be done from process context. So we record 117 * the success by setting devs[n].bio to IO_MADE_GOOD 118 */ 119 #define IO_MADE_GOOD ((struct bio *)2) 120 121 #define BIO_SPECIAL(bio) ((unsigned long)bio <= 2) 122 123 /* bits for r10bio.state */ 124 #define R10BIO_Uptodate 0 125 #define R10BIO_IsSync 1 126 #define R10BIO_IsRecover 2 127 #define R10BIO_Degraded 3 128 /* Set ReadError on bios that experience a read error 129 * so that raid10d knows what to do with them. 130 */ 131 #define R10BIO_ReadError 4 132 /* If a write for this request means we can clear some 133 * known-bad-block records, we set this flag. 134 */ 135 #define R10BIO_MadeGood 5 136 #define R10BIO_WriteError 6 137 #endif 138