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authorMike Snitzer <snitzer@redhat.com>2017-10-10 17:02:41 -0400
committerShaohua Li <shli@fb.com>2017-10-16 19:06:36 -0700
commit935fe0983e09f4f7331ebf5ea4ae2124f6e9f9e8 (patch)
treea3debe3ff3a5c4462b416f8992577d30c06a8a8a /drivers/md/bitmap.h
parent584ed9fa9532f8b9d5955628ff87ee3b2ab9f5a9 (diff)
downloadlinux-935fe0983e09f4f7331ebf5ea4ae2124f6e9f9e8.tar.bz2
md: rename some drivers/md/ files to have an "md-" prefix
Motivated by the desire to illiminate the imprecise nature of DM-specific patches being unnecessarily sent to both the MD maintainer and mailing-list. Which is born out of the fact that DM files also reside in drivers/md/ Now all MD-specific files in drivers/md/ start with either "raid" or "md-" and the MAINTAINERS file has been updated accordingly. Shaohua: don't change module name Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Shaohua Li <shli@fb.com>
Diffstat (limited to 'drivers/md/bitmap.h')
-rw-r--r--drivers/md/bitmap.h277
1 files changed, 0 insertions, 277 deletions
diff --git a/drivers/md/bitmap.h b/drivers/md/bitmap.h
deleted file mode 100644
index d15721ac07a6..000000000000
--- a/drivers/md/bitmap.h
+++ /dev/null
@@ -1,277 +0,0 @@
-/*
- * bitmap.h: Copyright (C) Peter T. Breuer (ptb@ot.uc3m.es) 2003
- *
- * additions: Copyright (C) 2003-2004, Paul Clements, SteelEye Technology, Inc.
- */
-#ifndef BITMAP_H
-#define BITMAP_H 1
-
-#define BITMAP_MAJOR_LO 3
-/* version 4 insists the bitmap is in little-endian order
- * with version 3, it is host-endian which is non-portable
- * Version 5 is currently set only for clustered devices
- */
-#define BITMAP_MAJOR_HI 4
-#define BITMAP_MAJOR_CLUSTERED 5
-#define BITMAP_MAJOR_HOSTENDIAN 3
-
-/*
- * in-memory bitmap:
- *
- * Use 16 bit block counters to track pending writes to each "chunk".
- * The 2 high order bits are special-purpose, the first is a flag indicating
- * whether a resync is needed. The second is a flag indicating whether a
- * resync is active.
- * This means that the counter is actually 14 bits:
- *
- * +--------+--------+------------------------------------------------+
- * | resync | resync | counter |
- * | needed | active | |
- * | (0-1) | (0-1) | (0-16383) |
- * +--------+--------+------------------------------------------------+
- *
- * The "resync needed" bit is set when:
- * a '1' bit is read from storage at startup.
- * a write request fails on some drives
- * a resync is aborted on a chunk with 'resync active' set
- * It is cleared (and resync-active set) when a resync starts across all drives
- * of the chunk.
- *
- *
- * The "resync active" bit is set when:
- * a resync is started on all drives, and resync_needed is set.
- * resync_needed will be cleared (as long as resync_active wasn't already set).
- * It is cleared when a resync completes.
- *
- * The counter counts pending write requests, plus the on-disk bit.
- * When the counter is '1' and the resync bits are clear, the on-disk
- * bit can be cleared as well, thus setting the counter to 0.
- * When we set a bit, or in the counter (to start a write), if the fields is
- * 0, we first set the disk bit and set the counter to 1.
- *
- * If the counter is 0, the on-disk bit is clear and the stripe is clean
- * Anything that dirties the stripe pushes the counter to 2 (at least)
- * and sets the on-disk bit (lazily).
- * If a periodic sweep find the counter at 2, it is decremented to 1.
- * If the sweep find the counter at 1, the on-disk bit is cleared and the
- * counter goes to zero.
- *
- * Also, we'll hijack the "map" pointer itself and use it as two 16 bit block
- * counters as a fallback when "page" memory cannot be allocated:
- *
- * Normal case (page memory allocated):
- *
- * page pointer (32-bit)
- *
- * [ ] ------+
- * |
- * +-------> [ ][ ]..[ ] (4096 byte page == 2048 counters)
- * c1 c2 c2048
- *
- * Hijacked case (page memory allocation failed):
- *
- * hijacked page pointer (32-bit)
- *
- * [ ][ ] (no page memory allocated)
- * counter #1 (16-bit) counter #2 (16-bit)
- *
- */
-
-#ifdef __KERNEL__
-
-#define PAGE_BITS (PAGE_SIZE << 3)
-#define PAGE_BIT_SHIFT (PAGE_SHIFT + 3)
-
-typedef __u16 bitmap_counter_t;
-#define COUNTER_BITS 16
-#define COUNTER_BIT_SHIFT 4
-#define COUNTER_BYTE_SHIFT (COUNTER_BIT_SHIFT - 3)
-
-#define NEEDED_MASK ((bitmap_counter_t) (1 << (COUNTER_BITS - 1)))
-#define RESYNC_MASK ((bitmap_counter_t) (1 << (COUNTER_BITS - 2)))
-#define COUNTER_MAX ((bitmap_counter_t) RESYNC_MASK - 1)
-#define NEEDED(x) (((bitmap_counter_t) x) & NEEDED_MASK)
-#define RESYNC(x) (((bitmap_counter_t) x) & RESYNC_MASK)
-#define COUNTER(x) (((bitmap_counter_t) x) & COUNTER_MAX)
-
-/* how many counters per page? */
-#define PAGE_COUNTER_RATIO (PAGE_BITS / COUNTER_BITS)
-/* same, except a shift value for more efficient bitops */
-#define PAGE_COUNTER_SHIFT (PAGE_BIT_SHIFT - COUNTER_BIT_SHIFT)
-/* same, except a mask value for more efficient bitops */
-#define PAGE_COUNTER_MASK (PAGE_COUNTER_RATIO - 1)
-
-#define BITMAP_BLOCK_SHIFT 9
-
-#endif
-
-/*
- * bitmap structures:
- */
-
-#define BITMAP_MAGIC 0x6d746962
-
-/* use these for bitmap->flags and bitmap->sb->state bit-fields */
-enum bitmap_state {
- BITMAP_STALE = 1, /* the bitmap file is out of date or had -EIO */
- BITMAP_WRITE_ERROR = 2, /* A write error has occurred */
- BITMAP_HOSTENDIAN =15,
-};
-
-/* the superblock at the front of the bitmap file -- little endian */
-typedef struct bitmap_super_s {
- __le32 magic; /* 0 BITMAP_MAGIC */
- __le32 version; /* 4 the bitmap major for now, could change... */
- __u8 uuid[16]; /* 8 128 bit uuid - must match md device uuid */
- __le64 events; /* 24 event counter for the bitmap (1)*/
- __le64 events_cleared;/*32 event counter when last bit cleared (2) */
- __le64 sync_size; /* 40 the size of the md device's sync range(3) */
- __le32 state; /* 48 bitmap state information */
- __le32 chunksize; /* 52 the bitmap chunk size in bytes */
- __le32 daemon_sleep; /* 56 seconds between disk flushes */
- __le32 write_behind; /* 60 number of outstanding write-behind writes */
- __le32 sectors_reserved; /* 64 number of 512-byte sectors that are
- * reserved for the bitmap. */
- __le32 nodes; /* 68 the maximum number of nodes in cluster. */
- __u8 cluster_name[64]; /* 72 cluster name to which this md belongs */
- __u8 pad[256 - 136]; /* set to zero */
-} bitmap_super_t;
-
-/* notes:
- * (1) This event counter is updated before the eventcounter in the md superblock
- * When a bitmap is loaded, it is only accepted if this event counter is equal
- * to, or one greater than, the event counter in the superblock.
- * (2) This event counter is updated when the other one is *if*and*only*if* the
- * array is not degraded. As bits are not cleared when the array is degraded,
- * this represents the last time that any bits were cleared.
- * If a device is being added that has an event count with this value or
- * higher, it is accepted as conforming to the bitmap.
- * (3)This is the number of sectors represented by the bitmap, and is the range that
- * resync happens across. For raid1 and raid5/6 it is the size of individual
- * devices. For raid10 it is the size of the array.
- */
-
-#ifdef __KERNEL__
-
-/* the in-memory bitmap is represented by bitmap_pages */
-struct bitmap_page {
- /*
- * map points to the actual memory page
- */
- char *map;
- /*
- * in emergencies (when map cannot be alloced), hijack the map
- * pointer and use it as two counters itself
- */
- unsigned int hijacked:1;
- /*
- * If any counter in this page is '1' or '2' - and so could be
- * cleared then that page is marked as 'pending'
- */
- unsigned int pending:1;
- /*
- * count of dirty bits on the page
- */
- unsigned int count:30;
-};
-
-/* the main bitmap structure - one per mddev */
-struct bitmap {
-
- struct bitmap_counts {
- spinlock_t lock;
- struct bitmap_page *bp;
- unsigned long pages; /* total number of pages
- * in the bitmap */
- unsigned long missing_pages; /* number of pages
- * not yet allocated */
- unsigned long chunkshift; /* chunksize = 2^chunkshift
- * (for bitops) */
- unsigned long chunks; /* Total number of data
- * chunks for the array */
- } counts;
-
- struct mddev *mddev; /* the md device that the bitmap is for */
-
- __u64 events_cleared;
- int need_sync;
-
- struct bitmap_storage {
- struct file *file; /* backing disk file */
- struct page *sb_page; /* cached copy of the bitmap
- * file superblock */
- struct page **filemap; /* list of cache pages for
- * the file */
- unsigned long *filemap_attr; /* attributes associated
- * w/ filemap pages */
- unsigned long file_pages; /* number of pages in the file*/
- unsigned long bytes; /* total bytes in the bitmap */
- } storage;
-
- unsigned long flags;
-
- int allclean;
-
- atomic_t behind_writes;
- unsigned long behind_writes_used; /* highest actual value at runtime */
-
- /*
- * the bitmap daemon - periodically wakes up and sweeps the bitmap
- * file, cleaning up bits and flushing out pages to disk as necessary
- */
- unsigned long daemon_lastrun; /* jiffies of last run */
- unsigned long last_end_sync; /* when we lasted called end_sync to
- * update bitmap with resync progress */
-
- atomic_t pending_writes; /* pending writes to the bitmap file */
- wait_queue_head_t write_wait;
- wait_queue_head_t overflow_wait;
- wait_queue_head_t behind_wait;
-
- struct kernfs_node *sysfs_can_clear;
- int cluster_slot; /* Slot offset for clustered env */
-};
-
-/* the bitmap API */
-
-/* these are used only by md/bitmap */
-struct bitmap *bitmap_create(struct mddev *mddev, int slot);
-int bitmap_load(struct mddev *mddev);
-void bitmap_flush(struct mddev *mddev);
-void bitmap_destroy(struct mddev *mddev);
-
-void bitmap_print_sb(struct bitmap *bitmap);
-void bitmap_update_sb(struct bitmap *bitmap);
-void bitmap_status(struct seq_file *seq, struct bitmap *bitmap);
-
-int bitmap_setallbits(struct bitmap *bitmap);
-void bitmap_write_all(struct bitmap *bitmap);
-
-void bitmap_dirty_bits(struct bitmap *bitmap, unsigned long s, unsigned long e);
-
-/* these are exported */
-int bitmap_startwrite(struct bitmap *bitmap, sector_t offset,
- unsigned long sectors, int behind);
-void bitmap_endwrite(struct bitmap *bitmap, sector_t offset,
- unsigned long sectors, int success, int behind);
-int bitmap_start_sync(struct bitmap *bitmap, sector_t offset, sector_t *blocks, int degraded);
-void bitmap_end_sync(struct bitmap *bitmap, sector_t offset, sector_t *blocks, int aborted);
-void bitmap_close_sync(struct bitmap *bitmap);
-void bitmap_cond_end_sync(struct bitmap *bitmap, sector_t sector, bool force);
-void bitmap_sync_with_cluster(struct mddev *mddev,
- sector_t old_lo, sector_t old_hi,
- sector_t new_lo, sector_t new_hi);
-
-void bitmap_unplug(struct bitmap *bitmap);
-void bitmap_daemon_work(struct mddev *mddev);
-
-int bitmap_resize(struct bitmap *bitmap, sector_t blocks,
- int chunksize, int init);
-struct bitmap *get_bitmap_from_slot(struct mddev *mddev, int slot);
-int bitmap_copy_from_slot(struct mddev *mddev, int slot,
- sector_t *lo, sector_t *hi, bool clear_bits);
-void bitmap_free(struct bitmap *bitmap);
-void bitmap_wait_behind_writes(struct mddev *mddev);
-#endif
-
-#endif