Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/torvalds/linux-2.6

1 files changed, 277 insertions, 228 deletions

diff --git a/drivers/md/bitmap.c b/drivers/md/bitmap.c
index 1742435ce3a..ed4900ade93 100644
--- a/drivers/md/bitmap.c
+++ b/drivers/md/bitmap.c
@@ -13,7 +13,6 @@
  * Still to do:
  *
  * flush after percent set rather than just time based. (maybe both).
- * wait if count gets too high, wake when it drops to half.
  */
 
 #include <linux/blkdev.h>
@@ -30,6 +29,7 @@
 #include "md.h"
 #include "bitmap.h"
 
+#include <linux/dm-dirty-log.h>
 /* debug macros */
 
 #define DEBUG 0
@@ -51,9 +51,6 @@
 #define INJECT_FATAL_FAULT_3 0 /* undef */
 #endif
 
-//#define DPRINTK PRINTK /* set this NULL to avoid verbose debug output */
-#define DPRINTK(x...) do { } while(0)
-
 #ifndef PRINTK
 #  if DEBUG > 0
 #    define PRINTK(x...) printk(KERN_DEBUG x)
@@ -62,12 +59,11 @@
 #  endif
 #endif
 
-static inline char * bmname(struct bitmap *bitmap)
+static inline char *bmname(struct bitmap *bitmap)
 {
 	return bitmap->mddev ? mdname(bitmap->mddev) : "mdX";
 }
 
-
 /*
  * just a placeholder - calls kmalloc for bitmap pages
  */
@@ -78,7 +74,7 @@ static unsigned char *bitmap_alloc_page(struct bitmap *bitmap)
 #ifdef INJECT_FAULTS_1
 	page = NULL;
 #else
-	page = kmalloc(PAGE_SIZE, GFP_NOIO);
+	page = kzalloc(PAGE_SIZE, GFP_NOIO);
 #endif
 	if (!page)
 		printk("%s: bitmap_alloc_page FAILED\n", bmname(bitmap));
@@ -107,7 +103,8 @@ static void bitmap_free_page(struct bitmap *bitmap, unsigned char *page)
  * if we find our page, we increment the page's refcount so that it stays
  * allocated while we're using it
  */
-static int bitmap_checkpage(struct bitmap *bitmap, unsigned long page, int create)
+static int bitmap_checkpage(struct bitmap *bitmap,
+			    unsigned long page, int create)
 __releases(bitmap->lock)
 __acquires(bitmap->lock)
 {
@@ -121,7 +118,6 @@ __acquires(bitmap->lock)
 		return -EINVAL;
 	}
 
-
 	if (bitmap->bp[page].hijacked) /* it's hijacked, don't try to alloc */
 		return 0;
 
@@ -131,43 +127,34 @@ __acquires(bitmap->lock)
 	if (!create)
 		return -ENOENT;
 
-	spin_unlock_irq(&bitmap->lock);
-
 	/* this page has not been allocated yet */
 
-	if ((mappage = bitmap_alloc_page(bitmap)) == NULL) {
+	spin_unlock_irq(&bitmap->lock);
+	mappage = bitmap_alloc_page(bitmap);
+	spin_lock_irq(&bitmap->lock);
+
+	if (mappage == NULL) {
 		PRINTK("%s: bitmap map page allocation failed, hijacking\n",
 			bmname(bitmap));
 		/* failed - set the hijacked flag so that we can use the
 		 * pointer as a counter */
-		spin_lock_irq(&bitmap->lock);
 		if (!bitmap->bp[page].map)
 			bitmap->bp[page].hijacked = 1;
-		goto out;
-	}
-
-	/* got a page */
-
-	spin_lock_irq(&bitmap->lock);
-
-	/* recheck the page */
-
-	if (bitmap->bp[page].map || bitmap->bp[page].hijacked) {
+	} else if (bitmap->bp[page].map ||
+		   bitmap->bp[page].hijacked) {
 		/* somebody beat us to getting the page */
 		bitmap_free_page(bitmap, mappage);
 		return 0;
-	}
+	} else {
 
-	/* no page was in place and we have one, so install it */
+		/* no page was in place and we have one, so install it */
 
-	memset(mappage, 0, PAGE_SIZE);
-	bitmap->bp[page].map = mappage;
-	bitmap->missing_pages--;
-out:
+		bitmap->bp[page].map = mappage;
+		bitmap->missing_pages--;
+	}
 	return 0;
 }
 
-
 /* if page is completely empty, put it back on the free list, or dealloc it */
 /* if page was hijacked, unmark the flag so it might get alloced next time */
 /* Note: lock should be held when calling this */
@@ -183,26 +170,15 @@ static void bitmap_checkfree(struct bitmap *bitmap, unsigned long page)
 	if (bitmap->bp[page].hijacked) { /* page was hijacked, undo this now */
 		bitmap->bp[page].hijacked = 0;
 		bitmap->bp[page].map = NULL;
-		return;
+	} else {
+		/* normal case, free the page */
+		ptr = bitmap->bp[page].map;
+		bitmap->bp[page].map = NULL;
+		bitmap->missing_pages++;
+		bitmap_free_page(bitmap, ptr);
 	}
-
-	/* normal case, free the page */
-
-#if 0
-/* actually ... let's not.  We will probably need the page again exactly when
- * memory is tight and we are flusing to disk
- */
-	return;
-#else
-	ptr = bitmap->bp[page].map;
-	bitmap->bp[page].map = NULL;
-	bitmap->missing_pages++;
-	bitmap_free_page(bitmap, ptr);
-	return;
-#endif
 }
 
-
 /*
  * bitmap file handling - read and write the bitmap file and its superblock
  */
@@ -220,11 +196,14 @@ static struct page *read_sb_page(mddev_t *mddev, loff_t offset,
 
 	mdk_rdev_t *rdev;
 	sector_t target;
+	int did_alloc = 0;
 
-	if (!page)
+	if (!page) {
 		page = alloc_page(GFP_KERNEL);
-	if (!page)
-		return ERR_PTR(-ENOMEM);
+		if (!page)
+			return ERR_PTR(-ENOMEM);
+		did_alloc = 1;
+	}
 
 	list_for_each_entry(rdev, &mddev->disks, same_set) {
 		if (! test_bit(In_sync, &rdev->flags)
@@ -242,6 +221,8 @@ static struct page *read_sb_page(mddev_t *mddev, loff_t offset,
 			return page;
 		}
 	}
+	if (did_alloc)
+		put_page(page);
 	return ERR_PTR(-EIO);
 
 }
@@ -286,49 +267,51 @@ static int write_sb_page(struct bitmap *bitmap, struct page *page, int wait)
 	mddev_t *mddev = bitmap->mddev;
 
 	while ((rdev = next_active_rdev(rdev, mddev)) != NULL) {
-			int size = PAGE_SIZE;
-			loff_t offset = mddev->bitmap_info.offset;
-			if (page->index == bitmap->file_pages-1)
-				size = roundup(bitmap->last_page_size,
-					       bdev_logical_block_size(rdev->bdev));
-			/* Just make sure we aren't corrupting data or
-			 * metadata
-			 */
-			if (mddev->external) {
-				/* Bitmap could be anywhere. */
-				if (rdev->sb_start + offset + (page->index *(PAGE_SIZE/512)) >
-				    rdev->data_offset &&
-				    rdev->sb_start + offset < 
-				    rdev->data_offset + mddev->dev_sectors +
-				    (PAGE_SIZE/512))
-					goto bad_alignment;
-			} else if (offset < 0) {
-				/* DATA  BITMAP METADATA  */
-				if (offset
-				    + (long)(page->index * (PAGE_SIZE/512))
-				    + size/512 > 0)
-					/* bitmap runs in to metadata */
-					goto bad_alignment;
-				if (rdev->data_offset + mddev->dev_sectors
-				    > rdev->sb_start + offset)
-					/* data runs in to bitmap */
-					goto bad_alignment;
-			} else if (rdev->sb_start < rdev->data_offset) {
-				/* METADATA BITMAP DATA */
-				if (rdev->sb_start
-				    + offset
-				    + page->index*(PAGE_SIZE/512) + size/512
-				    > rdev->data_offset)
-					/* bitmap runs in to data */
-					goto bad_alignment;
-			} else {
-				/* DATA METADATA BITMAP - no problems */
-			}
-			md_super_write(mddev, rdev,
-				       rdev->sb_start + offset
-				       + page->index * (PAGE_SIZE/512),
-				       size,
-				       page);
+		int size = PAGE_SIZE;
+		loff_t offset = mddev->bitmap_info.offset;
+		if (page->index == bitmap->file_pages-1)
+			size = roundup(bitmap->last_page_size,
+				       bdev_logical_block_size(rdev->bdev));
+		/* Just make sure we aren't corrupting data or
+		 * metadata
+		 */
+		if (mddev->external) {
+			/* Bitmap could be anywhere. */
+			if (rdev->sb_start + offset + (page->index
+						       * (PAGE_SIZE/512))
+			    > rdev->data_offset
+			    &&
+			    rdev->sb_start + offset
+			    < (rdev->data_offset + mddev->dev_sectors
+			     + (PAGE_SIZE/512)))
+				goto bad_alignment;
+		} else if (offset < 0) {
+			/* DATA  BITMAP METADATA  */
+			if (offset
+			    + (long)(page->index * (PAGE_SIZE/512))
+			    + size/512 > 0)
+				/* bitmap runs in to metadata */
+				goto bad_alignment;
+			if (rdev->data_offset + mddev->dev_sectors
+			    > rdev->sb_start + offset)
+				/* data runs in to bitmap */
+				goto bad_alignment;
+		} else if (rdev->sb_start < rdev->data_offset) {
+			/* METADATA BITMAP DATA */
+			if (rdev->sb_start
+			    + offset
+			    + page->index*(PAGE_SIZE/512) + size/512
+			    > rdev->data_offset)
+				/* bitmap runs in to data */
+				goto bad_alignment;
+		} else {
+			/* DATA METADATA BITMAP - no problems */
+		}
+		md_super_write(mddev, rdev,
+			       rdev->sb_start + offset
+			       + page->index * (PAGE_SIZE/512),
+			       size,
+			       page);
 	}
 
 	if (wait)
@@ -364,10 +347,9 @@ static void write_page(struct bitmap *bitmap, struct page *page, int wait)
 			bh = bh->b_this_page;
 		}
 
-		if (wait) {
+		if (wait)
 			wait_event(bitmap->write_wait,
 				   atomic_read(&bitmap->pending_writes)==0);
-		}
 	}
 	if (bitmap->flags & BITMAP_WRITE_ERROR)
 		bitmap_file_kick(bitmap);
@@ -424,7 +406,7 @@ static struct page *read_page(struct file *file, unsigned long index,
 	struct buffer_head *bh;
 	sector_t block;
 
-	PRINTK("read bitmap file (%dB @ %Lu)\n", (int)PAGE_SIZE,
+	PRINTK("read bitmap file (%dB @ %llu)\n", (int)PAGE_SIZE,
 			(unsigned long long)index << PAGE_SHIFT);
 
 	page = alloc_page(GFP_KERNEL);
@@ -478,7 +460,7 @@ static struct page *read_page(struct file *file, unsigned long index,
 	}
 out:
 	if (IS_ERR(page))
-		printk(KERN_ALERT "md: bitmap read error: (%dB @ %Lu): %ld\n",
+		printk(KERN_ALERT "md: bitmap read error: (%dB @ %llu): %ld\n",
 			(int)PAGE_SIZE,
 			(unsigned long long)index << PAGE_SHIFT,
 			PTR_ERR(page));
@@ -664,11 +646,14 @@ static int bitmap_mask_state(struct bitmap *bitmap, enum bitmap_state bits,
 	sb = kmap_atomic(bitmap->sb_page, KM_USER0);
 	old = le32_to_cpu(sb->state) & bits;
 	switch (op) {
-		case MASK_SET: sb->state |= cpu_to_le32(bits);
-				break;
-		case MASK_UNSET: sb->state &= cpu_to_le32(~bits);
-				break;
-		default: BUG();
+	case MASK_SET:
+		sb->state |= cpu_to_le32(bits);
+		break;
+	case MASK_UNSET:
+		sb->state &= cpu_to_le32(~bits);
+		break;
+	default:
+		BUG();
 	}
 	kunmap_atomic(sb, KM_USER0);
 	return old;
@@ -710,12 +695,14 @@ static inline unsigned long file_page_offset(struct bitmap *bitmap, unsigned lon
 static inline struct page *filemap_get_page(struct bitmap *bitmap,
 					unsigned long chunk)
 {
-	if (file_page_index(bitmap, chunk) >= bitmap->file_pages) return NULL;
+	if (bitmap->filemap == NULL)
+		return NULL;
+	if (file_page_index(bitmap, chunk) >= bitmap->file_pages)
+		return NULL;
 	return bitmap->filemap[file_page_index(bitmap, chunk)
 			       - file_page_index(bitmap, 0)];
 }
 
-
 static void bitmap_file_unmap(struct bitmap *bitmap)
 {
 	struct page **map, *sb_page;
@@ -766,7 +753,6 @@ static void bitmap_file_put(struct bitmap *bitmap)
 	}
 }
 
-
 /*
  * bitmap_file_kick - if an error occurs while manipulating the bitmap file
  * then it is no longer reliable, so we stop using it and we mark the file
@@ -785,7 +771,6 @@ static void bitmap_file_kick(struct bitmap *bitmap)
 				ptr = d_path(&bitmap->file->f_path, path,
 					     PAGE_SIZE);
 
-
 			printk(KERN_ALERT
 			      "%s: kicking failed bitmap file %s from array!\n",
 			      bmname(bitmap), IS_ERR(ptr) ? "" : ptr);
@@ -803,27 +788,36 @@ static void bitmap_file_kick(struct bitmap *bitmap)
 }
 
 enum bitmap_page_attr {
-	BITMAP_PAGE_DIRTY = 0, // there are set bits that need to be synced
-	BITMAP_PAGE_CLEAN = 1, // there are bits that might need to be cleared
-	BITMAP_PAGE_NEEDWRITE=2, // there are cleared bits that need to be synced
+	BITMAP_PAGE_DIRTY = 0,     /* there are set bits that need to be synced */
+	BITMAP_PAGE_CLEAN = 1,     /* there are bits that might need to be cleared */
+	BITMAP_PAGE_NEEDWRITE = 2, /* there are cleared bits that need to be synced */
 };
 
 static inline void set_page_attr(struct bitmap *bitmap, struct page *page,
 				enum bitmap_page_attr attr)
 {
-	__set_bit((page->index<<2) + attr, bitmap->filemap_attr);
+	if (page)
+		__set_bit((page->index<<2) + attr, bitmap->filemap_attr);
+	else
+		__set_bit(attr, &bitmap->logattrs);
 }
 
 static inline void clear_page_attr(struct bitmap *bitmap, struct page *page,
 				enum bitmap_page_attr attr)
 {
-	__clear_bit((page->index<<2) + attr, bitmap->filemap_attr);
+	if (page)
+		__clear_bit((page->index<<2) + attr, bitmap->filemap_attr);
+	else
+		__clear_bit(attr, &bitmap->logattrs);
 }
 
 static inline unsigned long test_page_attr(struct bitmap *bitmap, struct page *page,
 					   enum bitmap_page_attr attr)
 {
-	return test_bit((page->index<<2) + attr, bitmap->filemap_attr);
+	if (page)
+		return test_bit((page->index<<2) + attr, bitmap->filemap_attr);
+	else
+		return test_bit(attr, &bitmap->logattrs);
 }
 
 /*
@@ -836,30 +830,32 @@ static inline unsigned long test_page_attr(struct bitmap *bitmap, struct page *p
 static void bitmap_file_set_bit(struct bitmap *bitmap, sector_t block)
 {
 	unsigned long bit;
-	struct page *page;
+	struct page *page = NULL;
 	void *kaddr;
 	unsigned long chunk = block >> CHUNK_BLOCK_SHIFT(bitmap);
 
 	if (!bitmap->filemap) {
-		return;
-	}
-
-	page = filemap_get_page(bitmap, chunk);
-	if (!page) return;
-	bit = file_page_offset(bitmap, chunk);
+		struct dm_dirty_log *log = bitmap->mddev->bitmap_info.log;
+		if (log)
+			log->type->mark_region(log, chunk);
+	} else {
 
- 	/* set the bit */
-	kaddr = kmap_atomic(page, KM_USER0);
-	if (bitmap->flags & BITMAP_HOSTENDIAN)
-		set_bit(bit, kaddr);
-	else
-		ext2_set_bit(bit, kaddr);
-	kunmap_atomic(kaddr, KM_USER0);
-	PRINTK("set file bit %lu page %lu\n", bit, page->index);
+		page = filemap_get_page(bitmap, chunk);
+		if (!page)
+			return;
+		bit = file_page_offset(bitmap, chunk);
 
+		/* set the bit */
+		kaddr = kmap_atomic(page, KM_USER0);
+		if (bitmap->flags & BITMAP_HOSTENDIAN)
+			set_bit(bit, kaddr);
+		else
+			ext2_set_bit(bit, kaddr);
+		kunmap_atomic(kaddr, KM_USER0);
+		PRINTK("set file bit %lu page %lu\n", bit, page->index);
+	}
 	/* record page number so it gets flushed to disk when unplug occurs */
 	set_page_attr(bitmap, page, BITMAP_PAGE_DIRTY);
-
 }
 
 /* this gets called when the md device is ready to unplug its underlying
@@ -874,6 +870,16 @@ void bitmap_unplug(struct bitmap *bitmap)
 
 	if (!bitmap)
 		return;
+	if (!bitmap->filemap) {
+		/* Must be using a dirty_log */
+		struct dm_dirty_log *log = bitmap->mddev->bitmap_info.log;
+		dirty = test_and_clear_bit(BITMAP_PAGE_DIRTY, &bitmap->logattrs);
+		need_write = test_and_clear_bit(BITMAP_PAGE_NEEDWRITE, &bitmap->logattrs);
+		if (dirty || need_write)
+			if (log->type->flush(log))
+				bitmap->flags |= BITMAP_WRITE_ERROR;
+		goto out;
+	}
 
 	/* look at each page to see if there are any set bits that need to be
 	 * flushed out to disk */
@@ -892,7 +898,7 @@ void bitmap_unplug(struct bitmap *bitmap)
 			wait = 1;
 		spin_unlock_irqrestore(&bitmap->lock, flags);
 
-		if (dirty | need_write)
+		if (dirty || need_write)
 			write_page(bitmap, page, 0);
 	}
 	if (wait) { /* if any writes were performed, we need to wait on them */
@@ -902,9 +908,11 @@ void bitmap_unplug(struct bitmap *bitmap)
 		else
 			md_super_wait(bitmap->mddev);
 	}
+out:
 	if (bitmap->flags & BITMAP_WRITE_ERROR)
 		bitmap_file_kick(bitmap);
 }
+EXPORT_SYMBOL(bitmap_unplug);
 
 static void bitmap_set_memory_bits(struct bitmap *bitmap, sector_t offset, int needed);
 /* * bitmap_init_from_disk -- called at bitmap_create time to initialize
@@ -943,12 +951,11 @@ static int bitmap_init_from_disk(struct bitmap *bitmap, sector_t start)
 		printk(KERN_INFO "%s: bitmap file is out of date, doing full "
 			"recovery\n", bmname(bitmap));
 
-	bytes = (chunks + 7) / 8;
+	bytes = DIV_ROUND_UP(bitmap->chunks, 8);
 	if (!bitmap->mddev->bitmap_info.external)
 		bytes += sizeof(bitmap_super_t);
 
-	
-	num_pages = (bytes + PAGE_SIZE - 1) / PAGE_SIZE;
+	num_pages = DIV_ROUND_UP(bytes, PAGE_SIZE);
 
 	if (file && i_size_read(file->f_mapping->host) < bytes) {
 		printk(KERN_INFO "%s: bitmap file too short %lu < %lu\n",
@@ -966,7 +973,7 @@ static int bitmap_init_from_disk(struct bitmap *bitmap, sector_t start)
 
 	/* We need 4 bits per page, rounded up to a multiple of sizeof(unsigned long) */
 	bitmap->filemap_attr = kzalloc(
-		roundup( DIV_ROUND_UP(num_pages*4, 8), sizeof(unsigned long)),
+		roundup(DIV_ROUND_UP(num_pages*4, 8), sizeof(unsigned long)),
 		GFP_KERNEL);
 	if (!bitmap->filemap_attr)
 		goto err;
@@ -1021,7 +1028,7 @@ static int bitmap_init_from_disk(struct bitmap *bitmap, sector_t start)
 			if (outofdate) {
 				/*
 				 * if bitmap is out of date, dirty the
-			 	 * whole page and write it out
+				 * whole page and write it out
 				 */
 				paddr = kmap_atomic(page, KM_USER0);
 				memset(paddr + offset, 0xff,
@@ -1052,7 +1059,7 @@ static int bitmap_init_from_disk(struct bitmap *bitmap, sector_t start)
 		}
 	}
 
- 	/* everything went OK */
+	/* everything went OK */
 	ret = 0;
 	bitmap_mask_state(bitmap, BITMAP_STALE, MASK_UNSET);
 
@@ -1080,21 +1087,16 @@ void bitmap_write_all(struct bitmap *bitmap)
 	 */
 	int i;
 
-	for (i=0; i < bitmap->file_pages; i++)
+	for (i = 0; i < bitmap->file_pages; i++)
 		set_page_attr(bitmap, bitmap->filemap[i],
 			      BITMAP_PAGE_NEEDWRITE);
 }
 
-
 static void bitmap_count_page(struct bitmap *bitmap, sector_t offset, int inc)
 {
 	sector_t chunk = offset >> CHUNK_BLOCK_SHIFT(bitmap);
 	unsigned long page = chunk >> PAGE_COUNTER_SHIFT;
 	bitmap->bp[page].count += inc;
-/*
-	if (page == 0) printk("count page 0, offset %llu: %d gives %d\n",
-			      (unsigned long long)offset, inc, bitmap->bp[page].count);
-*/
 	bitmap_checkfree(bitmap, page);
 }
 static bitmap_counter_t *bitmap_get_counter(struct bitmap *bitmap,
@@ -1114,6 +1116,7 @@ void bitmap_daemon_work(mddev_t *mddev)
 	struct page *page = NULL, *lastpage = NULL;
 	int blocks;
 	void *paddr;
+	struct dm_dirty_log *log = mddev->bitmap_info.log;
 
 	/* Use a mutex to guard daemon_work against
 	 * bitmap_destroy.
@@ -1138,11 +1141,12 @@ void bitmap_daemon_work(mddev_t *mddev)
 	spin_lock_irqsave(&bitmap->lock, flags);
 	for (j = 0; j < bitmap->chunks; j++) {
 		bitmap_counter_t *bmc;
-		if (!bitmap->filemap)
-			/* error or shutdown */
-			break;
-
-		page = filemap_get_page(bitmap, j);
+		if (!bitmap->filemap) {
+			if (!log)
+				/* error or shutdown */
+				break;
+		} else
+			page = filemap_get_page(bitmap, j);
 
 		if (page != lastpage) {
 			/* skip this page unless it's marked as needing cleaning */
@@ -1197,14 +1201,11 @@ void bitmap_daemon_work(mddev_t *mddev)
 					 (sector_t)j << CHUNK_BLOCK_SHIFT(bitmap),
 					 &blocks, 0);
 		if (bmc) {
-/*
-  if (j < 100) printk("bitmap: j=%lu, *bmc = 0x%x\n", j, *bmc);
-*/
 			if (*bmc)
 				bitmap->allclean = 0;
 
 			if (*bmc == 2) {
-				*bmc=1; /* maybe clear the bit next time */
+				*bmc = 1; /* maybe clear the bit next time */
 				set_page_attr(bitmap, page, BITMAP_PAGE_CLEAN);
 			} else if (*bmc == 1 && !bitmap->need_sync) {
 				/* we can clear the bit */
@@ -1214,14 +1215,17 @@ void bitmap_daemon_work(mddev_t *mddev)
 						  -1);
 
 				/* clear the bit */
-				paddr = kmap_atomic(page, KM_USER0);
-				if (bitmap->flags & BITMAP_HOSTENDIAN)
-					clear_bit(file_page_offset(bitmap, j),
-						  paddr);
-				else
-					ext2_clear_bit(file_page_offset(bitmap, j),
-						       paddr);
-				kunmap_atomic(paddr, KM_USER0);
+				if (page) {
+					paddr = kmap_atomic(page, KM_USER0);
+					if (bitmap->flags & BITMAP_HOSTENDIAN)
+						clear_bit(file_page_offset(bitmap, j),
+							  paddr);
+					else
+						ext2_clear_bit(file_page_offset(bitmap, j),
+							       paddr);
+					kunmap_atomic(paddr, KM_USER0);
+				} else
+					log->type->clear_region(log, j);
 			}
 		} else
 			j |= PAGE_COUNTER_MASK;
@@ -1229,12 +1233,16 @@ void bitmap_daemon_work(mddev_t *mddev)
 	spin_unlock_irqrestore(&bitmap->lock, flags);
 
 	/* now sync the final page */
-	if (lastpage != NULL) {
+	if (lastpage != NULL || log != NULL) {
 		spin_lock_irqsave(&bitmap->lock, flags);
 		if (test_page_attr(bitmap, lastpage, BITMAP_PAGE_NEEDWRITE)) {
 			clear_page_attr(bitmap, lastpage, BITMAP_PAGE_NEEDWRITE);
 			spin_unlock_irqrestore(&bitmap->lock, flags);
-			write_page(bitmap, lastpage, 0);
+			if (lastpage)
+				write_page(bitmap, lastpage, 0);
+			else
+				if (log->type->flush(log))
+					bitmap->flags |= BITMAP_WRITE_ERROR;
 		} else {
 			set_page_attr(bitmap, lastpage, BITMAP_PAGE_NEEDWRITE);
 			spin_unlock_irqrestore(&bitmap->lock, flags);
@@ -1243,7 +1251,7 @@ void bitmap_daemon_work(mddev_t *mddev)
 
  done:
 	if (bitmap->allclean == 0)
-		bitmap->mddev->thread->timeout = 
+		bitmap->mddev->thread->timeout =
 			bitmap->mddev->bitmap_info.daemon_sleep;
 	mutex_unlock(&mddev->bitmap_info.mutex);
 }
@@ -1262,34 +1270,38 @@ __acquires(bitmap->lock)
 	unsigned long page = chunk >> PAGE_COUNTER_SHIFT;
 	unsigned long pageoff = (chunk & PAGE_COUNTER_MASK) << COUNTER_BYTE_SHIFT;
 	sector_t csize;
+	int err;
 
-	if (bitmap_checkpage(bitmap, page, create) < 0) {
+	err = bitmap_checkpage(bitmap, page, create);
+
+	if (bitmap->bp[page].hijacked ||
+	    bitmap->bp[page].map == NULL)
+		csize = ((sector_t)1) << (CHUNK_BLOCK_SHIFT(bitmap) +
+					  PAGE_COUNTER_SHIFT - 1);
+	else
 		csize = ((sector_t)1) << (CHUNK_BLOCK_SHIFT(bitmap));
-		*blocks = csize - (offset & (csize- 1));
+	*blocks = csize - (offset & (csize - 1));
+
+	if (err < 0)
 		return NULL;
-	}
+
 	/* now locked ... */
 
 	if (bitmap->bp[page].hijacked) { /* hijacked pointer */
 		/* should we use the first or second counter field
 		 * of the hijacked pointer? */
 		int hi = (pageoff > PAGE_COUNTER_MASK);
-		csize = ((sector_t)1) << (CHUNK_BLOCK_SHIFT(bitmap) +
-					  PAGE_COUNTER_SHIFT - 1);
-		*blocks = csize - (offset & (csize- 1));
 		return  &((bitmap_counter_t *)
 			  &bitmap->bp[page].map)[hi];
-	} else { /* page is allocated */
-		csize = ((sector_t)1) << (CHUNK_BLOCK_SHIFT(bitmap));
-		*blocks = csize - (offset & (csize- 1));
+	} else /* page is allocated */
 		return (bitmap_counter_t *)
 			&(bitmap->bp[page].map[pageoff]);
-	}
 }
 
 int bitmap_startwrite(struct bitmap *bitmap, sector_t offset, unsigned long sectors, int behind)
 {
-	if (!bitmap) return 0;
+	if (!bitmap)
+		return 0;
 
 	if (behind) {
 		int bw;
@@ -1322,17 +1334,16 @@ int bitmap_startwrite(struct bitmap *bitmap, sector_t offset, unsigned long sect
 			prepare_to_wait(&bitmap->overflow_wait, &__wait,
 					TASK_UNINTERRUPTIBLE);
 			spin_unlock_irq(&bitmap->lock);
-			blk_unplug(bitmap->mddev->queue);
+			md_unplug(bitmap->mddev);
 			schedule();
 			finish_wait(&bitmap->overflow_wait, &__wait);
 			continue;
 		}
 
-		switch(*bmc) {
+		switch (*bmc) {
 		case 0:
 			bitmap_file_set_bit(bitmap, offset);
-			bitmap_count_page(bitmap,offset, 1);
-			blk_plug_device_unlocked(bitmap->mddev->queue);
+			bitmap_count_page(bitmap, offset, 1);
 			/* fall through */
 		case 1:
 			*bmc = 2;
@@ -1345,16 +1356,19 @@ int bitmap_startwrite(struct bitmap *bitmap, sector_t offset, unsigned long sect
 		offset += blocks;
 		if (sectors > blocks)
 			sectors -= blocks;
-		else sectors = 0;
+		else
+			sectors = 0;
 	}
 	bitmap->allclean = 0;
 	return 0;
 }
+EXPORT_SYMBOL(bitmap_startwrite);
 
 void bitmap_endwrite(struct bitmap *bitmap, sector_t offset, unsigned long sectors,
 		     int success, int behind)
 {
-	if (!bitmap) return;
+	if (!bitmap)
+		return;
 	if (behind) {
 		if (atomic_dec_and_test(&bitmap->behind_writes))
 			wake_up(&bitmap->behind_wait);
@@ -1381,7 +1395,7 @@ void bitmap_endwrite(struct bitmap *bitmap, sector_t offset, unsigned long secto
 		    bitmap->events_cleared < bitmap->mddev->events) {
 			bitmap->events_cleared = bitmap->mddev->events;
 			bitmap->need_sync = 1;
-			sysfs_notify_dirent(bitmap->sysfs_can_clear);
+			sysfs_notify_dirent_safe(bitmap->sysfs_can_clear);
 		}
 
 		if (!success && ! (*bmc & NEEDED_MASK))
@@ -1391,18 +1405,22 @@ void bitmap_endwrite(struct bitmap *bitmap, sector_t offset, unsigned long secto
 			wake_up(&bitmap->overflow_wait);
 
 		(*bmc)--;
-		if (*bmc <= 2) {
+		if (*bmc <= 2)
 			set_page_attr(bitmap,
-				      filemap_get_page(bitmap, offset >> CHUNK_BLOCK_SHIFT(bitmap)),
+				      filemap_get_page(
+					      bitmap,
+					      offset >> CHUNK_BLOCK_SHIFT(bitmap)),
 				      BITMAP_PAGE_CLEAN);
-		}
+
 		spin_unlock_irqrestore(&bitmap->lock, flags);
 		offset += blocks;
 		if (sectors > blocks)
 			sectors -= blocks;
-		else sectors = 0;
+		else
+			sectors = 0;
 	}
 }
+EXPORT_SYMBOL(bitmap_endwrite);
 
 static int __bitmap_start_sync(struct bitmap *bitmap, sector_t offset, int *blocks,
 			       int degraded)
@@ -1455,14 +1473,14 @@ int bitmap_start_sync(struct bitmap *bitmap, sector_t offset, int *blocks,
 	}
 	return rv;
 }
+EXPORT_SYMBOL(bitmap_start_sync);
 
 void bitmap_end_sync(struct bitmap *bitmap, sector_t offset, int *blocks, int aborted)
 {
 	bitmap_counter_t *bmc;
 	unsigned long flags;
-/*
-	if (offset == 0) printk("bitmap_end_sync 0 (%d)\n", aborted);
-*/	if (bitmap == NULL) {
+
+	if (bitmap == NULL) {
 		*blocks = 1024;
 		return;
 	}
@@ -1471,26 +1489,23 @@ void bitmap_end_sync(struct bitmap *bitmap, sector_t offset, int *blocks, int ab
 	if (bmc == NULL)
 		goto unlock;
 	/* locked */
-/*
-	if (offset == 0) printk("bitmap_end sync found 0x%x, blocks %d\n", *bmc, *blocks);
-*/
 	if (RESYNC(*bmc)) {
 		*bmc &= ~RESYNC_MASK;
 
 		if (!NEEDED(*bmc) && aborted)
 			*bmc |= NEEDED_MASK;
 		else {
-			if (*bmc <= 2) {
+			if (*bmc <= 2)
 				set_page_attr(bitmap,
 					      filemap_get_page(bitmap, offset >> CHUNK_BLOCK_SHIFT(bitmap)),
 					      BITMAP_PAGE_CLEAN);
-			}
 		}
 	}
  unlock:
 	spin_unlock_irqrestore(&bitmap->lock, flags);
 	bitmap->allclean = 0;
 }
+EXPORT_SYMBOL(bitmap_end_sync);
 
 void bitmap_close_sync(struct bitmap *bitmap)
 {
@@ -1507,6 +1522,7 @@ void bitmap_close_sync(struct bitmap *bitmap)
 		sector += blocks;
 	}
 }
+EXPORT_SYMBOL(bitmap_close_sync);
 
 void bitmap_cond_end_sync(struct bitmap *bitmap, sector_t sector)
 {
@@ -1536,6 +1552,7 @@ void bitmap_cond_end_sync(struct bitmap *bitmap, sector_t sector)
 	bitmap->last_end_sync = jiffies;
 	sysfs_notify(&bitmap->mddev->kobj, NULL, "sync_completed");
 }
+EXPORT_SYMBOL(bitmap_cond_end_sync);
 
 static void bitmap_set_memory_bits(struct bitmap *bitmap, sector_t offset, int needed)
 {
@@ -1552,9 +1569,9 @@ static void bitmap_set_memory_bits(struct bitmap *bitmap, sector_t offset, int n
 		spin_unlock_irq(&bitmap->lock);
 		return;
 	}
-	if (! *bmc) {
+	if (!*bmc) {
 		struct page *page;
-		*bmc = 1 | (needed?NEEDED_MASK:0);
+		*bmc = 1 | (needed ? NEEDED_MASK : 0);
 		bitmap_count_page(bitmap, offset, 1);
 		page = filemap_get_page(bitmap, offset >> CHUNK_BLOCK_SHIFT(bitmap));
 		set_page_attr(bitmap, page, BITMAP_PAGE_CLEAN);
@@ -1663,15 +1680,17 @@ int bitmap_create(mddev_t *mddev)
 	unsigned long pages;
 	struct file *file = mddev->bitmap_info.file;
 	int err;
-	sector_t start;
-	struct sysfs_dirent *bm;
+	struct sysfs_dirent *bm = NULL;
 
 	BUILD_BUG_ON(sizeof(bitmap_super_t) != 256);
 
-	if (!file && !mddev->bitmap_info.offset) /* bitmap disabled, nothing to do */
+	if (!file
+	    && !mddev->bitmap_info.offset
+	    && !mddev->bitmap_info.log) /* bitmap disabled, nothing to do */
 		return 0;
 
 	BUG_ON(file && mddev->bitmap_info.offset);
+	BUG_ON(mddev->bitmap_info.offset && mddev->bitmap_info.log);
 
 	bitmap = kzalloc(sizeof(*bitmap), GFP_KERNEL);
 	if (!bitmap)
@@ -1685,7 +1704,8 @@ int bitmap_create(mddev_t *mddev)
 
 	bitmap->mddev = mddev;
 
-	bm = sysfs_get_dirent(mddev->kobj.sd, NULL, "bitmap");
+	if (mddev->kobj.sd)
+		bm = sysfs_get_dirent(mddev->kobj.sd, NULL, "bitmap");
 	if (bm) {
 		bitmap->sysfs_can_clear = sysfs_get_dirent(bm, NULL, "can_clear");
 		sysfs_put(bm);
@@ -1719,9 +1739,9 @@ int bitmap_create(mddev_t *mddev)
 	bitmap->chunkshift = ffz(~mddev->bitmap_info.chunksize);
 
 	/* now that chunksize and chunkshift are set, we can use these macros */
- 	chunks = (blocks + CHUNK_BLOCK_RATIO(bitmap) - 1) >>
+	chunks = (blocks + CHUNK_BLOCK_RATIO(bitmap) - 1) >>
 			CHUNK_BLOCK_SHIFT(bitmap);
- 	pages = (chunks + PAGE_COUNTER_RATIO - 1) / PAGE_COUNTER_RATIO;
+	pages = (chunks + PAGE_COUNTER_RATIO - 1) / PAGE_COUNTER_RATIO;
 
 	BUG_ON(!pages);
 
@@ -1741,27 +1761,11 @@ int bitmap_create(mddev_t *mddev)
 	if (!bitmap->bp)
 		goto error;
 
-	/* now that we have some pages available, initialize the in-memory
-	 * bitmap from the on-disk bitmap */
-	start = 0;
-	if (mddev->degraded == 0
-	    || bitmap->events_cleared == mddev->events)
-		/* no need to keep dirty bits to optimise a re-add of a missing device */
-		start = mddev->recovery_cp;
-	err = bitmap_init_from_disk(bitmap, start);
-
-	if (err)
-		goto error;
-
 	printk(KERN_INFO "created bitmap (%lu pages) for device %s\n",
 		pages, bmname(bitmap));
 
 	mddev->bitmap = bitmap;
 
-	mddev->thread->timeout = mddev->bitmap_info.daemon_sleep;
-	md_wakeup_thread(mddev->thread);
-
-	bitmap_update_sb(bitmap);
 
 	return (bitmap->flags & BITMAP_WRITE_ERROR) ? -EIO : 0;
 
@@ -1770,15 +1774,69 @@ int bitmap_create(mddev_t *mddev)
 	return err;
 }
 
+int bitmap_load(mddev_t *mddev)
+{
+	int err = 0;
+	sector_t sector = 0;
+	struct bitmap *bitmap = mddev->bitmap;
+
+	if (!bitmap)
+		goto out;
+
+	/* Clear out old bitmap info first:  Either there is none, or we
+	 * are resuming after someone else has possibly changed things,
+	 * so we should forget old cached info.
+	 * All chunks should be clean, but some might need_sync.
+	 */
+	while (sector < mddev->resync_max_sectors) {
+		int blocks;
+		bitmap_start_sync(bitmap, sector, &blocks, 0);
+		sector += blocks;
+	}
+	bitmap_close_sync(bitmap);
+
+	if (mddev->bitmap_info.log) {
+		unsigned long i;
+		struct dm_dirty_log *log = mddev->bitmap_info.log;
+		for (i = 0; i < bitmap->chunks; i++)
+			if (!log->type->in_sync(log, i, 1))
+				bitmap_set_memory_bits(bitmap,
+						       (sector_t)i << CHUNK_BLOCK_SHIFT(bitmap),
+						       1);
+	} else {
+		sector_t start = 0;
+		if (mddev->degraded == 0
+		    || bitmap->events_cleared == mddev->events)
+			/* no need to keep dirty bits to optimise a
+			 * re-add of a missing device */
+			start = mddev->recovery_cp;
+
+		err = bitmap_init_from_disk(bitmap, start);
+	}
+	if (err)
+		goto out;
+
+	mddev->thread->timeout = mddev->bitmap_info.daemon_sleep;
+	md_wakeup_thread(mddev->thread);
+
+	bitmap_update_sb(bitmap);
+
+	if (bitmap->flags & BITMAP_WRITE_ERROR)
+		err = -EIO;
+out:
+	return err;
+}
+EXPORT_SYMBOL_GPL(bitmap_load);
+
 static ssize_t
 location_show(mddev_t *mddev, char *page)
 {
 	ssize_t len;
-	if (mddev->bitmap_info.file) {
+	if (mddev->bitmap_info.file)
 		len = sprintf(page, "file");
-	} else if (mddev->bitmap_info.offset) {
+	else if (mddev->bitmap_info.offset)
 		len = sprintf(page, "%+lld", (long long)mddev->bitmap_info.offset);
-	} else
+	else
 		len = sprintf(page, "none");
 	len += sprintf(page+len, "\n");
 	return len;
@@ -1867,7 +1925,7 @@ timeout_show(mddev_t *mddev, char *page)
 	ssize_t len;
 	unsigned long secs = mddev->bitmap_info.daemon_sleep / HZ;
 	unsigned long jifs = mddev->bitmap_info.daemon_sleep % HZ;
-	
+
 	len = sprintf(page, "%lu", secs);
 	if (jifs)
 		len += sprintf(page+len, ".%03u", jiffies_to_msecs(jifs));
@@ -2049,12 +2107,3 @@ struct attribute_group md_bitmap_group = {
 	.attrs = md_bitmap_attrs,
 };
 
-
-/* the bitmap API -- for raid personalities */
-EXPORT_SYMBOL(bitmap_startwrite);
-EXPORT_SYMBOL(bitmap_endwrite);
-EXPORT_SYMBOL(bitmap_start_sync);
-EXPORT_SYMBOL(bitmap_end_sync);
-EXPORT_SYMBOL(bitmap_unplug);
-EXPORT_SYMBOL(bitmap_close_sync);
-EXPORT_SYMBOL(bitmap_cond_end_sync);