diff options
Diffstat (limited to 'drivers/md/raid5.h')
| -rw-r--r-- | drivers/md/raid5.h | 256 |
1 files changed, 161 insertions, 95 deletions
diff --git a/drivers/md/raid5.h b/drivers/md/raid5.h index dd708359b45..bc72cd4be5f 100644 --- a/drivers/md/raid5.h +++ b/drivers/md/raid5.h @@ -6,11 +6,11 @@ /* * - * Each stripe contains one buffer per disc. Each buffer can be in + * Each stripe contains one buffer per device. Each buffer can be in * one of a number of states stored in "flags". Changes between - * these states happen *almost* exclusively under a per-stripe - * spinlock. Some very specific changes can happen in bi_end_io, and - * these are not protected by the spin lock. + * these states happen *almost* exclusively under the protection of the + * STRIPE_ACTIVE flag. Some very specific changes can happen in bi_end_io, and + * these are not protected by STRIPE_ACTIVE. * * The flag bits that are used to represent these states are: * R5_UPTODATE and R5_LOCKED @@ -27,7 +27,7 @@ * The possible state transitions are: * * Empty -> Want - on read or write to get old data for parity calc - * Empty -> Dirty - on compute_parity to satisfy write/sync request.(RECONSTRUCT_WRITE) + * Empty -> Dirty - on compute_parity to satisfy write/sync request. * Empty -> Clean - on compute_block when computing a block for failed drive * Want -> Empty - on failed read * Want -> Clean - on successful completion of read request @@ -49,7 +49,7 @@ * can't distinguish between a clean block that has been generated * from parity calculations, and a clean block that has been * successfully written to the spare ( or to parity when resyncing). - * To distingush these states we have a stripe bit STRIPE_INSYNC that + * To distinguish these states we have a stripe bit STRIPE_INSYNC that * is set whenever a write is scheduled to the spare, or to the parity * disc if there is no spare. A sync request clears this bit, and * when we find it set with no buffers locked, we know the sync is @@ -76,12 +76,10 @@ * block and the cached buffer are successfully written, any buffer on * a written list can be returned with b_end_io. * - * The write list and read list both act as fifos. The read list is - * protected by the device_lock. The write and written lists are - * protected by the stripe lock. The device_lock, which can be - * claimed while the stipe lock is held, is only for list - * manipulations and will only be held for a very short time. It can - * be claimed from interrupts. + * The write list and read list both act as fifos. The read list, + * write list and written list are protected by the device_lock. + * The device_lock is only for list manipulations and will only be + * held for a very short time. It can be claimed from interrupts. * * * Stripes in the stripe cache can be on one of two lists (or on @@ -96,7 +94,6 @@ * * The inactive_list, handle_list and hash bucket lists are all protected by the * device_lock. - * - stripes on the inactive_list never have their stripe_lock held. * - stripes have a reference counter. If count==0, they are on a list. * - If a stripe might need handling, STRIPE_HANDLE is set. * - When refcount reaches zero, then if STRIPE_HANDLE it is put on @@ -116,10 +113,10 @@ * attach a request to an active stripe (add_stripe_bh()) * lockdev attach-buffer unlockdev * handle a stripe (handle_stripe()) - * lockstripe clrSTRIPE_HANDLE ... + * setSTRIPE_ACTIVE, clrSTRIPE_HANDLE ... * (lockdev check-buffers unlockdev) .. * change-state .. - * record io/ops needed unlockstripe schedule io/ops + * record io/ops needed clearSTRIPE_ACTIVE schedule io/ops * release an active stripe (release_stripe()) * lockdev if (!--cnt) { if STRIPE_HANDLE, add to handle_list else add to inactive-list } unlockdev * @@ -128,8 +125,7 @@ * on a cached buffer, and plus one if the stripe is undergoing stripe * operations. * - * Stripe operations are performed outside the stripe lock, - * the stripe operations are: + * The stripe operations are: * -copying data between the stripe cache and user application buffers * -computing blocks to save a disk access, or to recover a missing block * -updating the parity on a write operation (reconstruct write and @@ -159,7 +155,8 @@ */ /* - * Operations state - intermediate states that are visible outside of sh->lock + * Operations state - intermediate states that are visible outside of + * STRIPE_ACTIVE. * In general _idle indicates nothing is running, _run indicates a data * processing operation is active, and _result means the data processing result * is stable and can be acted upon. For simple operations like biofill and @@ -200,20 +197,24 @@ enum reconstruct_states { struct stripe_head { struct hlist_node hash; struct list_head lru; /* inactive_list or handle_list */ - struct raid5_private_data *raid_conf; + struct llist_node release_list; + struct r5conf *raid_conf; short generation; /* increments with every * reshape */ sector_t sector; /* sector of this row */ short pd_idx; /* parity disk index */ short qd_idx; /* 'Q' disk index for raid6 */ short ddf_layout;/* use DDF ordering to calculate Q */ + short hash_lock_index; unsigned long state; /* state flags */ atomic_t count; /* nr of active thread/requests */ - spinlock_t lock; int bm_seq; /* sequence number for bitmap flushes */ int disks; /* disks in stripe */ enum check_states check_state; enum reconstruct_states reconstruct_state; + spinlock_t stripe_lock; + int cpu; + struct r5worker_group *group; /** * struct stripe_operations * @target - STRIPE_OP_COMPUTE_BLK target @@ -224,15 +225,14 @@ struct stripe_head { struct stripe_operations { int target, target2; enum sum_check_flags zero_sum_result; - #ifdef CONFIG_MULTICORE_RAID456 - unsigned long request; - wait_queue_head_t wait_for_ops; - #endif } ops; struct r5dev { - struct bio req; - struct bio_vec vec; - struct page *page; + /* rreq and rvec are used for the replacement device when + * writing data to both devices. + */ + struct bio req, rreq; + struct bio_vec vec, rvec; + struct page *page, *orig_page; struct bio *toread, *read, *towrite, *written; sector_t sector; /* sector of this page */ unsigned long flags; @@ -240,80 +240,106 @@ struct stripe_head { }; /* stripe_head_state - collects and tracks the dynamic state of a stripe_head - * for handle_stripe. It is only valid under spin_lock(sh->lock); + * for handle_stripe. */ struct stripe_head_state { - int syncing, expanding, expanded; + /* 'syncing' means that we need to read all devices, either + * to check/correct parity, or to reconstruct a missing device. + * 'replacing' means we are replacing one or more drives and + * the source is valid at this point so we don't need to + * read all devices, just the replacement targets. + */ + int syncing, expanding, expanded, replacing; int locked, uptodate, to_read, to_write, failed, written; int to_fill, compute, req_compute, non_overwrite; - int failed_num; + int failed_num[2]; + int p_failed, q_failed; + int dec_preread_active; unsigned long ops_request; -}; -/* r6_state - extra state data only relevant to r6 */ -struct r6_state { - int p_failed, q_failed, failed_num[2]; + struct bio *return_bi; + struct md_rdev *blocked_rdev; + int handle_bad_blocks; }; -/* Flags */ -#define R5_UPTODATE 0 /* page contains current data */ -#define R5_LOCKED 1 /* IO has been submitted on "req" */ -#define R5_OVERWRITE 2 /* towrite covers whole page */ +/* Flags for struct r5dev.flags */ +enum r5dev_flags { + R5_UPTODATE, /* page contains current data */ + R5_LOCKED, /* IO has been submitted on "req" */ + R5_DOUBLE_LOCKED,/* Cannot clear R5_LOCKED until 2 writes complete */ + R5_OVERWRITE, /* towrite covers whole page */ /* and some that are internal to handle_stripe */ -#define R5_Insync 3 /* rdev && rdev->in_sync at start */ -#define R5_Wantread 4 /* want to schedule a read */ -#define R5_Wantwrite 5 -#define R5_Overlap 7 /* There is a pending overlapping request on this block */ -#define R5_ReadError 8 /* seen a read error here recently */ -#define R5_ReWrite 9 /* have tried to over-write the readerror */ - -#define R5_Expanded 10 /* This block now has post-expand data */ -#define R5_Wantcompute 11 /* compute_block in progress treat as - * uptodate - */ -#define R5_Wantfill 12 /* dev->toread contains a bio that needs - * filling - */ -#define R5_Wantdrain 13 /* dev->towrite needs to be drained */ -/* - * Write method - */ -#define RECONSTRUCT_WRITE 1 -#define READ_MODIFY_WRITE 2 -/* not a write method, but a compute_parity mode */ -#define CHECK_PARITY 3 -/* Additional compute_parity mode -- updates the parity w/o LOCKING */ -#define UPDATE_PARITY 4 + R5_Insync, /* rdev && rdev->in_sync at start */ + R5_Wantread, /* want to schedule a read */ + R5_Wantwrite, + R5_Overlap, /* There is a pending overlapping request + * on this block */ + R5_ReadNoMerge, /* prevent bio from merging in block-layer */ + R5_ReadError, /* seen a read error here recently */ + R5_ReWrite, /* have tried to over-write the readerror */ + + R5_Expanded, /* This block now has post-expand data */ + R5_Wantcompute, /* compute_block in progress treat as + * uptodate + */ + R5_Wantfill, /* dev->toread contains a bio that needs + * filling + */ + R5_Wantdrain, /* dev->towrite needs to be drained */ + R5_WantFUA, /* Write should be FUA */ + R5_SyncIO, /* The IO is sync */ + R5_WriteError, /* got a write error - need to record it */ + R5_MadeGood, /* A bad block has been fixed by writing to it */ + R5_ReadRepl, /* Will/did read from replacement rather than orig */ + R5_MadeGoodRepl,/* A bad block on the replacement device has been + * fixed by writing to it */ + R5_NeedReplace, /* This device has a replacement which is not + * up-to-date at this stripe. */ + R5_WantReplace, /* We need to update the replacement, we have read + * data in, and now is a good time to write it out. + */ + R5_Discard, /* Discard the stripe */ + R5_SkipCopy, /* Don't copy data from bio to stripe cache */ +}; /* * Stripe state */ -#define STRIPE_HANDLE 2 -#define STRIPE_SYNCING 3 -#define STRIPE_INSYNC 4 -#define STRIPE_PREREAD_ACTIVE 5 -#define STRIPE_DELAYED 6 -#define STRIPE_DEGRADED 7 -#define STRIPE_BIT_DELAY 8 -#define STRIPE_EXPANDING 9 -#define STRIPE_EXPAND_SOURCE 10 -#define STRIPE_EXPAND_READY 11 -#define STRIPE_IO_STARTED 12 /* do not count towards 'bypass_count' */ -#define STRIPE_FULL_WRITE 13 /* all blocks are set to be overwritten */ -#define STRIPE_BIOFILL_RUN 14 -#define STRIPE_COMPUTE_RUN 15 -#define STRIPE_OPS_REQ_PENDING 16 +enum { + STRIPE_ACTIVE, + STRIPE_HANDLE, + STRIPE_SYNC_REQUESTED, + STRIPE_SYNCING, + STRIPE_INSYNC, + STRIPE_REPLACED, + STRIPE_PREREAD_ACTIVE, + STRIPE_DELAYED, + STRIPE_DEGRADED, + STRIPE_BIT_DELAY, + STRIPE_EXPANDING, + STRIPE_EXPAND_SOURCE, + STRIPE_EXPAND_READY, + STRIPE_IO_STARTED, /* do not count towards 'bypass_count' */ + STRIPE_FULL_WRITE, /* all blocks are set to be overwritten */ + STRIPE_BIOFILL_RUN, + STRIPE_COMPUTE_RUN, + STRIPE_OPS_REQ_PENDING, + STRIPE_ON_UNPLUG_LIST, + STRIPE_DISCARD, + STRIPE_ON_RELEASE_LIST, +}; /* * Operation request flags */ -#define STRIPE_OP_BIOFILL 0 -#define STRIPE_OP_COMPUTE_BLK 1 -#define STRIPE_OP_PREXOR 2 -#define STRIPE_OP_BIODRAIN 3 -#define STRIPE_OP_RECONSTRUCT 4 -#define STRIPE_OP_CHECK 5 - +enum { + STRIPE_OP_BIOFILL, + STRIPE_OP_COMPUTE_BLK, + STRIPE_OP_PREXOR, + STRIPE_OP_BIODRAIN, + STRIPE_OP_RECONSTRUCT, + STRIPE_OP_CHECK, +}; /* * Plugging: * @@ -335,18 +361,41 @@ struct r6_state { * PREREAD_ACTIVE. * In stripe_handle, if we find pre-reading is necessary, we do it if * PREREAD_ACTIVE is set, else we set DELAYED which will send it to the delayed queue. - * HANDLE gets cleared if stripe_handle leave nothing locked. + * HANDLE gets cleared if stripe_handle leaves nothing locked. */ struct disk_info { - mdk_rdev_t *rdev; + struct md_rdev *rdev, *replacement; }; -struct raid5_private_data { +/* NOTE NR_STRIPE_HASH_LOCKS must remain below 64. + * This is because we sometimes take all the spinlocks + * and creating that much locking depth can cause + * problems. + */ +#define NR_STRIPE_HASH_LOCKS 8 +#define STRIPE_HASH_LOCKS_MASK (NR_STRIPE_HASH_LOCKS - 1) + +struct r5worker { + struct work_struct work; + struct r5worker_group *group; + struct list_head temp_inactive_list[NR_STRIPE_HASH_LOCKS]; + bool working; +}; + +struct r5worker_group { + struct list_head handle_list; + struct r5conf *conf; + struct r5worker *workers; + int stripes_cnt; +}; + +struct r5conf { struct hlist_head *stripe_hashtbl; - mddev_t *mddev; - struct disk_info *spare; + /* only protect corresponding hash list and inactive_list */ + spinlock_t hash_locks[NR_STRIPE_HASH_LOCKS]; + struct mddev *mddev; int chunk_sectors; int level, algorithm; int max_degraded; @@ -367,8 +416,15 @@ struct raid5_private_data { int prev_chunk_sectors; int prev_algo; short generation; /* increments with every reshape */ + seqcount_t gen_lock; /* lock against generation changes */ unsigned long reshape_checkpoint; /* Time we last updated * metadata */ + long long min_offset_diff; /* minimum difference between + * data_offset and + * new_data_offset across all + * devices. May be negative, + * but is closest to zero. + */ struct list_head handle_list; /* stripes needing handling */ struct list_head hold_list; /* preread ready stripes */ @@ -381,6 +437,7 @@ struct raid5_private_data { atomic_t pending_full_writes; /* full write backlog */ int bypass_count; /* bypassed prereads */ int bypass_threshold; /* preread nice */ + int skip_copy; /* Don't copy data from bio to stripe cache */ struct list_head *last_hold; /* detect hold_list promotions */ atomic_t reshape_stripes; /* stripes with pending writes for reshape */ @@ -388,7 +445,7 @@ struct raid5_private_data { * two caches. */ int active_name; - char cache_name[2][20]; + char cache_name[2][32]; struct kmem_cache *slab_cache; /* for allocating stripes */ int seq_flush, seq_write; @@ -398,6 +455,7 @@ struct raid5_private_data { * (fresh device added). * Cleared when a sync completes. */ + int recovery_disabled; /* per cpu variables */ struct raid5_percpu { struct page *spare_page; /* Used when checking P/Q in raid6 */ @@ -405,7 +463,7 @@ struct raid5_private_data { * lists and performing address * conversions */ - } *percpu; + } __percpu *percpu; size_t scribble_len; /* size of scribble region must be * associated with conf to handle * cpu hotplug while reshaping @@ -418,7 +476,9 @@ struct raid5_private_data { * Free stripes pool */ atomic_t active_stripes; - struct list_head inactive_list; + struct list_head inactive_list[NR_STRIPE_HASH_LOCKS]; + atomic_t empty_inactive_list_nr; + struct llist_head released_stripes; wait_queue_head_t wait_for_stripe; wait_queue_head_t wait_for_overlap; int inactive_blocked; /* release of inactive stripes blocked, @@ -431,11 +491,13 @@ struct raid5_private_data { /* When taking over an array from a different personality, we store * the new thread here until we fully activate the array. */ - struct mdk_thread_s *thread; + struct md_thread *thread; + struct list_head temp_inactive_list[NR_STRIPE_HASH_LOCKS]; + struct r5worker_group *worker_groups; + int group_cnt; + int worker_cnt_per_group; }; -typedef struct raid5_private_data raid5_conf_t; - /* * Our supported algorithms */ @@ -497,4 +559,8 @@ static inline int algorithm_is_DDF(int layout) { return layout >= 8 && layout <= 10; } + +extern int md_raid5_congested(struct mddev *mddev, int bits); +extern void md_raid5_kick_device(struct r5conf *conf); +extern int raid5_set_cache_size(struct mddev *mddev, int size); #endif |