1 #ifndef _RAID10_H 2 #define _RAID10_H 3 4 struct mirror_info { 5 struct md_rdev *rdev, *replacement; 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 struct mirror_info *mirrors_new, *mirrors_old; 18 spinlock_t device_lock; 19 20 /* geometry */ 21 struct geom { 22 int raid_disks; 23 int near_copies; /* number of copies laid out 24 * raid0 style */ 25 int far_copies; /* number of copies laid out 26 * at large strides across drives 27 */ 28 int far_offset; /* far_copies are offset by 1 29 * stripe instead of many 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 int chunk_shift; /* shift from chunks to sectors */ 37 sector_t chunk_mask; 38 } prev, geo; 39 int copies; /* near_copies * far_copies. 40 * must be <= raid_disks 41 */ 42 43 sector_t dev_sectors; /* temp copy of 44 * mddev->dev_sectors */ 45 sector_t reshape_progress; 46 sector_t reshape_safe; 47 unsigned long reshape_checkpoint; 48 sector_t offset_diff; 49 50 struct list_head retry_list; 51 /* queue pending writes and submit them on unplug */ 52 struct bio_list pending_bio_list; 53 int pending_count; 54 55 spinlock_t resync_lock; 56 int nr_pending; 57 int nr_waiting; 58 int nr_queued; 59 int barrier; 60 sector_t next_resync; 61 int fullsync; /* set to 1 if a full sync is needed, 62 * (fresh device added). 63 * Cleared when a sync completes. 64 */ 65 int have_replacement; /* There is at least one 66 * replacement device. 67 */ 68 wait_queue_head_t wait_barrier; 69 70 mempool_t *r10bio_pool; 71 mempool_t *r10buf_pool; 72 struct page *tmppage; 73 74 /* When taking over an array from a different personality, we store 75 * the new thread here until we fully activate the array. 76 */ 77 struct md_thread *thread; 78 }; 79 80 /* 81 * this is our 'private' RAID10 bio. 82 * 83 * it contains information about what kind of IO operations were started 84 * for this RAID10 operation, and about their status: 85 */ 86 87 struct r10bio { 88 atomic_t remaining; /* 'have we finished' count, 89 * used from IRQ handlers 90 */ 91 sector_t sector; /* virtual sector number */ 92 int sectors; 93 unsigned long state; 94 struct mddev *mddev; 95 /* 96 * original bio going to /dev/mdx 97 */ 98 struct bio *master_bio; 99 /* 100 * if the IO is in READ direction, then this is where we read 101 */ 102 int read_slot; 103 104 struct list_head retry_list; 105 /* 106 * if the IO is in WRITE direction, then multiple bios are used, 107 * one for each copy. 108 * When resyncing we also use one for each copy. 109 * When reconstructing, we use 2 bios, one for read, one for write. 110 * We choose the number when they are allocated. 111 * We sometimes need an extra bio to write to the replacement. 112 */ 113 struct { 114 struct bio *bio; 115 union { 116 struct bio *repl_bio; /* used for resync and 117 * writes */ 118 struct md_rdev *rdev; /* used for reads 119 * (read_slot >= 0) */ 120 }; 121 sector_t addr; 122 int devnum; 123 } devs[0]; 124 }; 125 126 /* when we get a read error on a read-only array, we redirect to another 127 * device without failing the first device, or trying to over-write to 128 * correct the read error. To keep track of bad blocks on a per-bio 129 * level, we store IO_BLOCKED in the appropriate 'bios' pointer 130 */ 131 #define IO_BLOCKED ((struct bio*)1) 132 /* When we successfully write to a known bad-block, we need to remove the 133 * bad-block marking which must be done from process context. So we record 134 * the success by setting devs[n].bio to IO_MADE_GOOD 135 */ 136 #define IO_MADE_GOOD ((struct bio *)2) 137 138 #define BIO_SPECIAL(bio) ((unsigned long)bio <= 2) 139 140 /* bits for r10bio.state */ 141 enum r10bio_state { 142 R10BIO_Uptodate, 143 R10BIO_IsSync, 144 R10BIO_IsRecover, 145 R10BIO_IsReshape, 146 R10BIO_Degraded, 147 /* Set ReadError on bios that experience a read error 148 * so that raid10d knows what to do with them. 149 */ 150 R10BIO_ReadError, 151 /* If a write for this request means we can clear some 152 * known-bad-block records, we set this flag. 153 */ 154 R10BIO_MadeGood, 155 R10BIO_WriteError, 156 /* During a reshape we might be performing IO on the 157 * 'previous' part of the array, in which case this 158 * flag is set 159 */ 160 R10BIO_Previous, 161 }; 162 #endif 163