drivers/md/md-bitmap.h

3  * bitmap.h: Copyright (C) Peter T. Breuer (ptb@ot.uc3m.es) 2003
11 /* version 4 insists the bitmap is in little-endian order
20  * in-memory bitmap:
110  * bitmap structures:
115 /* use these for bitmap->flags and bitmap->sb->state bit-fields */
117 	BITMAP_STALE	   = 1,  /* the bitmap file is out of date or had -EIO */
122 /* the superblock at the front of the bitmap file -- little endian */
125 	__le32 version;      /*  4  the bitmap major for now, could change... */
127 	__le64 events;       /* 24  event counter for the bitmap (1)*/
130 	__le32 state;        /* 48  bitmap state information */
131 	__le32 chunksize;    /* 52  the bitmap chunk size in bytes */
135 				  * reserved for the bitmap. */
143  *    When a bitmap is loaded, it is only accepted if this event counter is equal
149  *    higher, it is accepted as conforming to the bitmap.
150  * (3)This is the number of sectors represented by the bitmap, and is the range that
157 /* the in-memory bitmap is represented by bitmap_pages */
179 /* the main bitmap structure - one per mddev */
180 struct bitmap {
186 						 * in the bitmap */
195 	struct mddev *mddev; /* the md device that the bitmap is for */
202 		struct page *sb_page;		/* cached copy of the bitmap
210 		unsigned long bytes;		/* total bytes in the bitmap */
221 	 * the bitmap daemon - periodically wakes up and sweeps the bitmap
226 				      * update bitmap with resync progress */
228 	atomic_t pending_writes; /* pending writes to the bitmap file */
237 /* the bitmap API */
239 /* these are used only by md/bitmap */
240 struct bitmap *md_bitmap_create(struct mddev *mddev, int slot);
245 void md_bitmap_print_sb(struct bitmap *bitmap);
246 void md_bitmap_update_sb(struct bitmap *bitmap);
247 void md_bitmap_status(struct seq_file *seq, struct bitmap *bitmap);
249 int  md_bitmap_setallbits(struct bitmap *bitmap);
250 void md_bitmap_write_all(struct bitmap *bitmap);
252 void md_bitmap_dirty_bits(struct bitmap *bitmap, unsigned long s, unsigned long e);
255 int md_bitmap_startwrite(struct bitmap *bitmap, sector_t offset,
257 void md_bitmap_endwrite(struct bitmap *bitmap, sector_t offset,
259 int md_bitmap_start_sync(struct bitmap *bitmap, sector_t offset, sector_t *blocks, int degraded);
260 void md_bitmap_end_sync(struct bitmap *bitmap, sector_t offset, sector_t *blocks, int aborted);
261 void md_bitmap_close_sync(struct bitmap *bitmap);
262 void md_bitmap_cond_end_sync(struct bitmap *bitmap, sector_t sector, bool force);
267 void md_bitmap_unplug(struct bitmap *bitmap);
268 void md_bitmap_unplug_async(struct bitmap *bitmap);
271 int md_bitmap_resize(struct bitmap *bitmap, sector_t blocks,
273 struct bitmap *get_bitmap_from_slot(struct mddev *mddev, int slot);
276 void md_bitmap_free(struct bitmap *bitmap);
279 static inline bool md_bitmap_enabled(struct bitmap *bitmap)
281 	return bitmap && bitmap->storage.filemap &&
282 	       !test_bit(BITMAP_STALE, &bitmap->flags);