Commit ec7a3197 authored by NeilBrown's avatar NeilBrown Committed by Linus Torvalds
Browse files

[PATCH] md/bitmap: cleaner separation of page attribute handlers in md/bitmap 



md/bitmap has some attributes per-page.  Handling of these attributes in
largely abstracted in set_page_attr and clear_page_attr.  However
get_page_attr exposes the format used to store them.  So prior to changing
that format, introduce test_page_attr instead of get_page_attr, and make
appropriate usage changes.

Signed-off-by: default avatarNeil Brown <neilb@suse.de>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent 0b79ccf0

drivers/md/bitmap.c

+22 −19
Original line number Diff line number Diff line
@@ -717,9 +717,10 @@ static inline void clear_page_attr(struct bitmap *bitmap, struct page *page, 
	bitmap->filemap_attr[page->index] &= ~attr;

}



static inline unsigned long get_page_attr(struct bitmap *bitmap, struct page *page)

static inline unsigned long test_page_attr(struct bitmap *bitmap, struct page *page,

					   enum bitmap_page_attr attr)

{

	return bitmap->filemap_attr[page->index];

	return bitmap->filemap_attr[page->index] & attr;

}



/*
@@ -745,7 +746,7 @@ static void bitmap_file_set_bit(struct bitmap *bitmap, sector_t block) 




	/* make sure the page stays cached until it gets written out */

	if (! (get_page_attr(bitmap, page) & BITMAP_PAGE_DIRTY))

	if (! test_page_attr(bitmap, page, BITMAP_PAGE_DIRTY))

		get_page(page);



 	/* set the bit */
@@ -769,7 +770,8 @@ static void bitmap_writeback(struct bitmap *bitmap); 
 * sync the dirty pages of the bitmap file to disk */

int bitmap_unplug(struct bitmap *bitmap)

{

	unsigned long i, attr, flags;

	unsigned long i, flags;

	int dirty, need_write;

	struct page *page;

	int wait = 0;

	int err;
@@ -786,17 +788,18 @@ int bitmap_unplug(struct bitmap *bitmap) 
			return 0;

		}

		page = bitmap->filemap[i];

		attr = get_page_attr(bitmap, page);

		dirty = test_page_attr(bitmap, page, BITMAP_PAGE_DIRTY);

		need_write = test_page_attr(bitmap, page, BITMAP_PAGE_NEEDWRITE);

		clear_page_attr(bitmap, page, BITMAP_PAGE_DIRTY);

		clear_page_attr(bitmap, page, BITMAP_PAGE_NEEDWRITE);

		if ((attr & BITMAP_PAGE_DIRTY))

		if (dirty)

			wait = 1;

		spin_unlock_irqrestore(&bitmap->lock, flags);



		if (attr & (BITMAP_PAGE_DIRTY | BITMAP_PAGE_NEEDWRITE)) {

		if (dirty | need_write) {

			err = write_page(bitmap, page, 0);

			if (err == -EAGAIN) {

				if (attr & BITMAP_PAGE_DIRTY)

				if (dirty)

					err = write_page(bitmap, page, 1);

				else

					err = 0;
@@ -961,12 +964,11 @@ void bitmap_write_all(struct bitmap *bitmap) 
	/* We don't actually write all bitmap blocks here,

	 * just flag them as needing to be written

	 */

	int i;



	unsigned long chunks = bitmap->chunks;

	unsigned long bytes = (chunks+7)/8 + sizeof(bitmap_super_t);

	unsigned long num_pages = (bytes + PAGE_SIZE-1) / PAGE_SIZE;

	while (num_pages--)

		bitmap->filemap_attr[num_pages] |= BITMAP_PAGE_NEEDWRITE;

	for (i=0; i < bitmap->file_pages; i++)

		set_page_attr(bitmap, bitmap->filemap[i],

			      BITMAP_PAGE_NEEDWRITE);

}
@@ -997,7 +999,6 @@ int bitmap_daemon_work(struct bitmap *bitmap) 
	struct page *page = NULL, *lastpage = NULL;

	int err = 0;

	int blocks;

	int attr;

	void *paddr;



	if (bitmap == NULL)
@@ -1019,13 +1020,15 @@ int bitmap_daemon_work(struct bitmap *bitmap) 


		if (page != lastpage) {

			/* skip this page unless it's marked as needing cleaning */

			if (!((attr=get_page_attr(bitmap, page)) & BITMAP_PAGE_CLEAN)) {

				if (attr & BITMAP_PAGE_NEEDWRITE) {

			if (!test_page_attr(bitmap, page, BITMAP_PAGE_CLEAN)) {

				int need_write = test_page_attr(bitmap, page,

								BITMAP_PAGE_NEEDWRITE);

				if (need_write) {

					get_page(page);

					clear_page_attr(bitmap, page, BITMAP_PAGE_NEEDWRITE);

				}

				spin_unlock_irqrestore(&bitmap->lock, flags);

				if (attr & BITMAP_PAGE_NEEDWRITE) {

				if (need_write) {

					switch (write_page(bitmap, page, 0)) {

					case -EAGAIN:

						set_page_attr(bitmap, page, BITMAP_PAGE_NEEDWRITE);
@@ -1043,7 +1046,7 @@ int bitmap_daemon_work(struct bitmap *bitmap) 
			/* grab the new page, sync and release the old */

			get_page(page);

			if (lastpage != NULL) {

				if (get_page_attr(bitmap, lastpage) & BITMAP_PAGE_NEEDWRITE) {

				if (test_page_attr(bitmap, lastpage, BITMAP_PAGE_NEEDWRITE)) {

					clear_page_attr(bitmap, lastpage, BITMAP_PAGE_NEEDWRITE);

					spin_unlock_irqrestore(&bitmap->lock, flags);

					err = write_page(bitmap, lastpage, 0);
@@ -1097,7 +1100,7 @@ int bitmap_daemon_work(struct bitmap *bitmap) 
	/* now sync the final page */

	if (lastpage != NULL) {

		spin_lock_irqsave(&bitmap->lock, flags);

		if (get_page_attr(bitmap, lastpage) &BITMAP_PAGE_NEEDWRITE) {

		if (test_page_attr(bitmap, lastpage, BITMAP_PAGE_NEEDWRITE)) {

			clear_page_attr(bitmap, lastpage, BITMAP_PAGE_NEEDWRITE);

			spin_unlock_irqrestore(&bitmap->lock, flags);

			err = write_page(bitmap, lastpage, 0);