md: move headers out of include/linux/raid/

Move the headers with the local structures for the disciplines and
bitmap.h into drivers/md/ so that they are more easily grepable for
hacking and not far away.  md.h is left where it is for now as there
are some uses from the outside.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: NeilBrown <neilb@suse.de>

1 files changed, 0 insertions, 402 deletions

diff --git a/include/linux/raid/raid5.h b/include/linux/raid/raid5.h
deleted file mode 100644
index 3b2672792457..000000000000
--- a/include/linux/raid/raid5.h
+++ /dev/null
@@ -1,402 +0,0 @@
-#ifndef _RAID5_H
-#define _RAID5_H
-
-#include <linux/raid/md.h>
-#include <linux/raid/xor.h>
-
-/*
- *
- * Each stripe contains one buffer per disc.  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.
- *
- * The flag bits that are used to represent these states are:
- *   R5_UPTODATE and R5_LOCKED
- *
- * State Empty == !UPTODATE, !LOCK
- *        We have no data, and there is no active request
- * State Want == !UPTODATE, LOCK
- *        A read request is being submitted for this block
- * State Dirty == UPTODATE, LOCK
- *        Some new data is in this buffer, and it is being written out
- * State Clean == UPTODATE, !LOCK
- *        We have valid data which is the same as on disc
- *
- * 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 -> Clean  - on compute_block when computing a block for failed drive
- *  Want  -> Empty  - on failed read
- *  Want  -> Clean  - on successful completion of read request
- *  Dirty -> Clean  - on successful completion of write request
- *  Dirty -> Clean  - on failed write
- *  Clean -> Dirty  - on compute_parity to satisfy write/sync (RECONSTRUCT or RMW)
- *
- * The Want->Empty, Want->Clean, Dirty->Clean, transitions
- * all happen in b_end_io at interrupt time.
- * Each sets the Uptodate bit before releasing the Lock bit.
- * This leaves one multi-stage transition:
- *    Want->Dirty->Clean
- * This is safe because thinking that a Clean buffer is actually dirty
- * will at worst delay some action, and the stripe will be scheduled
- * for attention after the transition is complete.
- *
- * There is one possibility that is not covered by these states.  That
- * is if one drive has failed and there is a spare being rebuilt.  We
- * 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
- * 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
- * complete.
- *
- * Buffers for the md device that arrive via make_request are attached
- * to the appropriate stripe in one of two lists linked on b_reqnext.
- * One list (bh_read) for read requests, one (bh_write) for write.
- * There should never be more than one buffer on the two lists
- * together, but we are not guaranteed of that so we allow for more.
- *
- * If a buffer is on the read list when the associated cache buffer is
- * Uptodate, the data is copied into the read buffer and it's b_end_io
- * routine is called.  This may happen in the end_request routine only
- * if the buffer has just successfully been read.  end_request should
- * remove the buffers from the list and then set the Uptodate bit on
- * the buffer.  Other threads may do this only if they first check
- * that the Uptodate bit is set.  Once they have checked that they may
- * take buffers off the read queue.
- *
- * When a buffer on the write list is committed for write it is copied
- * into the cache buffer, which is then marked dirty, and moved onto a
- * third list, the written list (bh_written).  Once both the parity
- * 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.
- *
- *
- * Stripes in the stripe cache can be on one of two lists (or on
- * neither).  The "inactive_list" contains stripes which are not
- * currently being used for any request.  They can freely be reused
- * for another stripe.  The "handle_list" contains stripes that need
- * to be handled in some way.  Both of these are fifo queues.  Each
- * stripe is also (potentially) linked to a hash bucket in the hash
- * table so that it can be found by sector number.  Stripes that are
- * not hashed must be on the inactive_list, and will normally be at
- * the front.  All stripes start life this way.
- *
- * 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
- *    handle_list else inactive_list
- *
- * This, combined with the fact that STRIPE_HANDLE is only ever
- * cleared while a stripe has a non-zero count means that if the
- * refcount is 0 and STRIPE_HANDLE is set, then it is on the
- * handle_list and if recount is 0 and STRIPE_HANDLE is not set, then
- * the stripe is on inactive_list.
- *
- * The possible transitions are:
- *  activate an unhashed/inactive stripe (get_active_stripe())
- *     lockdev check-hash unlink-stripe cnt++ clean-stripe hash-stripe unlockdev
- *  activate a hashed, possibly active stripe (get_active_stripe())
- *     lockdev check-hash if(!cnt++)unlink-stripe unlockdev
- *  attach a request to an active stripe (add_stripe_bh())
- *     lockdev attach-buffer unlockdev
- *  handle a stripe (handle_stripe())
- *     lockstripe clrSTRIPE_HANDLE ...
- *              (lockdev check-buffers unlockdev) ..
- *              change-state ..
- *              record io/ops needed unlockstripe 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
- *
- * The refcount counts each thread that have activated the stripe,
- * plus raid5d if it is handling it, plus one for each active request
- * 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:
- * -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
- *  read-modify-write)
- * -checking parity correctness
- * -running i/o to disk
- * These operations are carried out by raid5_run_ops which uses the async_tx
- * api to (optionally) offload operations to dedicated hardware engines.
- * When requesting an operation handle_stripe sets the pending bit for the
- * operation and increments the count.  raid5_run_ops is then run whenever
- * the count is non-zero.
- * There are some critical dependencies between the operations that prevent some
- * from being requested while another is in flight.
- * 1/ Parity check operations destroy the in cache version of the parity block,
- *    so we prevent parity dependent operations like writes and compute_blocks
- *    from starting while a check is in progress.  Some dma engines can perform
- *    the check without damaging the parity block, in these cases the parity
- *    block is re-marked up to date (assuming the check was successful) and is
- *    not re-read from disk.
- * 2/ When a write operation is requested we immediately lock the affected
- *    blocks, and mark them as not up to date.  This causes new read requests
- *    to be held off, as well as parity checks and compute block operations.
- * 3/ Once a compute block operation has been requested handle_stripe treats
- *    that block as if it is up to date.  raid5_run_ops guaruntees that any
- *    operation that is dependent on the compute block result is initiated after
- *    the compute block completes.
- */
-
-/*
- * Operations state - intermediate states that are visible outside of sh->lock
- * 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
- * compute that only have an _idle and _run state they are indicated with
- * sh->state flags (STRIPE_BIOFILL_RUN and STRIPE_COMPUTE_RUN)
- */
-/**
- * enum check_states - handles syncing / repairing a stripe
- * @check_state_idle - check operations are quiesced
- * @check_state_run - check operation is running
- * @check_state_result - set outside lock when check result is valid
- * @check_state_compute_run - check failed and we are repairing
- * @check_state_compute_result - set outside lock when compute result is valid
- */
-enum check_states {
-        check_state_idle = 0,
-        check_state_run, /* parity check */
-        check_state_check_result,
-        check_state_compute_run, /* parity repair */
-        check_state_compute_result,
-};
-
-/**
- * enum reconstruct_states - handles writing or expanding a stripe
- */
-enum reconstruct_states {
-        reconstruct_state_idle = 0,
-        reconstruct_state_prexor_drain_run,     /* prexor-write */
-        reconstruct_state_drain_run,            /* write */
-        reconstruct_state_run,                  /* expand */
-        reconstruct_state_prexor_drain_result,
-        reconstruct_state_drain_result,
-        reconstruct_state_result,
-};
-
-struct stripe_head {
-        struct hlist_node       hash;
-        struct list_head        lru;                    /* inactive_list or handle_list */
-        struct raid5_private_data       *raid_conf;
-        sector_t                sector;                 /* sector of this row */
-        int                     pd_idx;                 /* parity disk 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;
-        /* stripe_operations
-         * @target - STRIPE_OP_COMPUTE_BLK target
-         */
-        struct stripe_operations {
-                int                target;
-                u32                zero_sum_result;
-        } ops;
-        struct r5dev {
-                struct bio      req;
-                struct bio_vec  vec;
-                struct page     *page;
-                struct bio      *toread, *read, *towrite, *written;
-                sector_t        sector;                 /* sector of this page */
-                unsigned long   flags;
-        } dev[1]; /* allocated with extra space depending of RAID geometry */
-};
-
-/* 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);
- */
-struct stripe_head_state {
-        int syncing, expanding, expanded;
-        int locked, uptodate, to_read, to_write, failed, written;
-        int to_fill, compute, req_compute, non_overwrite;
-        int failed_num;
-        unsigned long ops_request;
-};
-
-/* r6_state - extra state data only relevant to r6 */
-struct r6_state {
-        int p_failed, q_failed, qd_idx, failed_num[2];
-};
-
-/* 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 */
-/* 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
-
-/*
- * 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
-/*
- * 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_POSTXOR       4
-#define STRIPE_OP_CHECK 5
-
-/*
- * Plugging:
- *
- * To improve write throughput, we need to delay the handling of some
- * stripes until there has been a chance that several write requests
- * for the one stripe have all been collected.
- * In particular, any write request that would require pre-reading
- * is put on a "delayed" queue until there are no stripes currently
- * in a pre-read phase.  Further, if the "delayed" queue is empty when
- * a stripe is put on it then we "plug" the queue and do not process it
- * until an unplug call is made. (the unplug_io_fn() is called).
- *
- * When preread is initiated on a stripe, we set PREREAD_ACTIVE and add
- * it to the count of prereading stripes.
- * When write is initiated, or the stripe refcnt == 0 (just in case) we
- * clear the PREREAD_ACTIVE flag and decrement the count
- * Whenever the 'handle' queue is empty and the device is not plugged, we
- * move any strips from delayed to handle and clear the DELAYED flag and set
- * 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.
- */
- 
-
-struct disk_info {
-        mdk_rdev_t      *rdev;
-};
-
-struct raid5_private_data {
-        struct hlist_head       *stripe_hashtbl;
-        mddev_t                 *mddev;
-        struct disk_info        *spare;
-        int                     chunk_size, level, algorithm;
-        int                     max_degraded;
-        int                     raid_disks;
-        int                     max_nr_stripes;
-
-        /* used during an expand */
-        sector_t                expand_progress;        /* MaxSector when no expand happening */
-        sector_t                expand_lo; /* from here up to expand_progress it out-of-bounds
-                                            * as we haven't flushed the metadata yet
-                                            */
-        int                     previous_raid_disks;
-
-        struct list_head        handle_list; /* stripes needing handling */
-        struct list_head        hold_list; /* preread ready stripes */
-        struct list_head        delayed_list; /* stripes that have plugged requests */
-        struct list_head        bitmap_list; /* stripes delaying awaiting bitmap update */
-        struct bio              *retry_read_aligned; /* currently retrying aligned bios   */
-        struct bio              *retry_read_aligned_list; /* aligned bios retry list  */
-        atomic_t                preread_active_stripes; /* stripes with scheduled io */
-        atomic_t                active_aligned_reads;
-        atomic_t                pending_full_writes; /* full write backlog */
-        int                     bypass_count; /* bypassed prereads */
-        int                     bypass_threshold; /* preread nice */
-        struct list_head        *last_hold; /* detect hold_list promotions */
-
-        atomic_t                reshape_stripes; /* stripes with pending writes for reshape */
-        /* unfortunately we need two cache names as we temporarily have
-         * two caches.
-         */
-        int                     active_name;
-        char                    cache_name[2][20];
-        struct kmem_cache               *slab_cache; /* for allocating stripes */
-
-        int                     seq_flush, seq_write;
-        int                     quiesce;
-
-        int                     fullsync;  /* set to 1 if a full sync is needed,
-                                            * (fresh device added).
-                                            * Cleared when a sync completes.
-                                            */
-
-        struct page             *spare_page; /* Used when checking P/Q in raid6 */
-
-        /*
-         * Free stripes pool
-         */
-        atomic_t                active_stripes;
-        struct list_head        inactive_list;
-        wait_queue_head_t       wait_for_stripe;
-        wait_queue_head_t       wait_for_overlap;
-        int                     inactive_blocked;       /* release of inactive stripes blocked,
-                                                         * waiting for 25% to be free
-                                                         */
-        int                     pool_size; /* number of disks in stripeheads in pool */
-        spinlock_t              device_lock;
-        struct disk_info        *disks;
-};
-
-typedef struct raid5_private_data raid5_conf_t;
-
-#define mddev_to_conf(mddev) ((raid5_conf_t *) mddev->private)
-
-/*
- * Our supported algorithms
- */
-#define ALGORITHM_LEFT_ASYMMETRIC       0
-#define ALGORITHM_RIGHT_ASYMMETRIC      1
-#define ALGORITHM_LEFT_SYMMETRIC        2
-#define ALGORITHM_RIGHT_SYMMETRIC       3
-
-#endif