Commit 1defeac9 authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Nathan Scott
Browse files

[XFS] clean up the xfs_offset_to_map interface Currently we pass a struct 


page and a relative offset into that page around, and returns the current
xfs_iomap_t if the block at the specified offset fits into it, or a NULL
pointer otherwise.  This patch passed the full 64bit offset into the inode
that all callers have anyway, and changes the return value to a simple
boolean.  Also the function gets a more descriptive name: xfs_iomap_valid.

SGI-PV: 947118
SGI-Modid: xfs-linux-melb:xfs-kern:203825a

Signed-off-by: default avatarChristoph Hellwig <hch@sgi.com>
Signed-off-by: default avatarNathan Scott <nathans@sgi.com>
parent 10ce4444

fs/xfs/linux-2.6/xfs_aops.c

+53 −83
Original line number Diff line number Diff line
@@ -228,29 +228,13 @@ xfs_map_blocks( 
	return -error;

}



/*

 * Finds the corresponding mapping in block @map array of the

 * given @offset within a @page.

 */

STATIC xfs_iomap_t *

xfs_offset_to_map(

	struct page		*page,

STATIC inline int

xfs_iomap_valid(

	xfs_iomap_t		*iomapp,

	unsigned long		offset)

	loff_t			offset)

{

	xfs_off_t		full_offset;	/* offset from start of file */



	ASSERT(offset < PAGE_CACHE_SIZE);



	full_offset = page->index;		/* NB: using 64bit number */

	full_offset <<= PAGE_CACHE_SHIFT;	/* offset from file start */

	full_offset += offset;			/* offset from page start */



	if (full_offset < iomapp->iomap_offset)

		return NULL;

	if (iomapp->iomap_offset + (iomapp->iomap_bsize -1) >= full_offset)

		return iomapp;

	return NULL;

	return offset >= iomapp->iomap_offset &&

		offset < iomapp->iomap_offset + iomapp->iomap_bsize;

}



/*
@@ -461,31 +445,23 @@ xfs_add_to_ioend( 


STATIC void

xfs_map_at_offset(

	struct page		*page,

	struct buffer_head	*bh,

	unsigned long		offset,

	loff_t			offset,

	int			block_bits,

	xfs_iomap_t		*iomapp,

	xfs_ioend_t		*ioend)

	xfs_iomap_t		*iomapp)

{

	xfs_daddr_t		bn;

	xfs_off_t		delta;

	int			sector_shift;



	ASSERT(!(iomapp->iomap_flags & IOMAP_HOLE));

	ASSERT(!(iomapp->iomap_flags & IOMAP_DELAY));

	ASSERT(iomapp->iomap_bn != IOMAP_DADDR_NULL);



	delta = page->index;

	delta <<= PAGE_CACHE_SHIFT;

	delta += offset;

	delta -= iomapp->iomap_offset;

	delta >>= block_bits;



	sector_shift = block_bits - BBSHIFT;

	bn = iomapp->iomap_bn >> sector_shift;

	bn += delta;

	BUG_ON(!bn && !(iomapp->iomap_flags & IOMAP_REALTIME));

	bn = (iomapp->iomap_bn >> sector_shift) +

	      ((offset - iomapp->iomap_offset) >> block_bits);



	ASSERT(bn || (iomapp->iomap_flags & IOMAP_REALTIME));

	ASSERT((bn << sector_shift) >= iomapp->iomap_bn);



	lock_buffer(bh);
@@ -569,8 +545,10 @@ xfs_probe_unmapped_cluster( 
			if (tindex == tlast) {

				pg_offset =

				    i_size_read(inode) & (PAGE_CACHE_SIZE - 1);

				if (!pg_offset)

				if (!pg_offset) {

					done = 1;

					break;

				}

			} else

				pg_offset = PAGE_CACHE_SIZE;
@@ -585,6 +563,7 @@ xfs_probe_unmapped_cluster( 
			}



			total += len;

			tindex++;

		}



		pagevec_release(&pvec);
@@ -638,19 +617,19 @@ xfs_convert_page( 
	struct inode		*inode,

	struct page		*page,

	loff_t			tindex,

	xfs_iomap_t		*iomapp,

	xfs_iomap_t		*mp,

	xfs_ioend_t		**ioendp,

	struct writeback_control *wbc,

	int			startio,

	int			all_bh)

{

	struct buffer_head	*bh, *head;

	xfs_iomap_t		*mp = iomapp, *tmp;

	unsigned long		p_offset, end_offset;

	unsigned int		type;

	int			bbits = inode->i_blkbits;

	int			len, page_dirty;

	int			count = 0, done = 0, uptodate = 1;

 	xfs_off_t		f_offset = page_offset(page);



	if (page->index != tindex)

		goto fail;
@@ -703,15 +682,15 @@ xfs_convert_page( 
			}

			continue;

		}

		tmp = xfs_offset_to_map(page, mp, p_offset);

		if (!tmp) {



		if (!xfs_iomap_valid(mp, f_offset + p_offset)) {

			done = 1;

			continue;

		}

		ASSERT(!(tmp->iomap_flags & IOMAP_HOLE));

		ASSERT(!(tmp->iomap_flags & IOMAP_DELAY));

		ASSERT(!(mp->iomap_flags & IOMAP_HOLE));

		ASSERT(!(mp->iomap_flags & IOMAP_DELAY));



		xfs_map_at_offset(page, bh, p_offset, bbits, tmp, *ioendp);

		xfs_map_at_offset(bh, f_offset + p_offset, bbits, mp);

		if (startio) {

			xfs_add_to_ioend(inode, bh, p_offset,

					type, ioendp, done);
@@ -805,15 +784,14 @@ xfs_page_state_convert( 
	int		unmapped) /* also implies page uptodate */

{

	struct buffer_head	*bh, *head;

	xfs_iomap_t		*iomp, iomap;

	xfs_iomap_t		iomap;

	xfs_ioend_t		*ioend = NULL, *iohead = NULL;

	loff_t			offset;

	unsigned long           p_offset = 0;

	unsigned int		type;

	__uint64_t              end_offset;

	pgoff_t                 end_index, last_index, tlast;

	int			flags, len, err, done = 1;

	int			uptodate = 1;

	int			flags, len, err, iomap_valid = 0, uptodate = 1;

	int			page_dirty, count = 0, trylock_flag = 0;



	/* wait for other IO threads? */
@@ -854,11 +832,9 @@ xfs_page_state_convert( 
	p_offset = p_offset ? roundup(p_offset, len) : PAGE_CACHE_SIZE;

	page_dirty = p_offset / len;



	iomp = NULL;

	bh = head = page_buffers(page);

	offset = page_offset(page);



	/* TODO: fix up "done" variable and iomap pointer (boolean) */

	/* TODO: cleanup count and page_dirty */



	do {
@@ -867,14 +843,16 @@ xfs_page_state_convert( 
		if (!buffer_uptodate(bh))

			uptodate = 0;

		if (!(PageUptodate(page) || buffer_uptodate(bh)) && !startio) {

			done = 1;

			/*

			 * the iomap is actually still valid, but the ioend

			 * isn't.  shouldn't happen too often.

			 */

			iomap_valid = 0;

			continue;

		}



		if (iomp) {

			iomp = xfs_offset_to_map(page, &iomap, p_offset);

			done = (iomp == NULL);

		}

		if (iomap_valid)

			iomap_valid = xfs_iomap_valid(&iomap, offset);



		/*

		 * First case, map an unwritten extent and prepare for
@@ -894,22 +872,20 @@ xfs_page_state_convert( 
					flags |= trylock_flag;

			}



			if (!iomp) {

				done = 1;

			if (!iomap_valid) {

				err = xfs_map_blocks(inode, offset, len, &iomap,

						flags);

				if (err)

					goto error;

				iomp = xfs_offset_to_map(page, &iomap,

								p_offset);

				done = (iomp == NULL);

				iomap_valid = xfs_iomap_valid(&iomap, offset);

			}

			if (iomp) {

				xfs_map_at_offset(page, bh, p_offset,

						inode->i_blkbits, iomp, ioend);

			if (iomap_valid) {

				xfs_map_at_offset(bh, offset,

						inode->i_blkbits, &iomap);

				if (startio) {

					xfs_add_to_ioend(inode, bh, p_offset,

						type, &ioend, done);

							type, &ioend,

							!iomap_valid);

				} else {

					set_buffer_dirty(bh);

					unlock_buffer(bh);
@@ -917,8 +893,6 @@ xfs_page_state_convert( 
				}

				page_dirty--;

				count++;

			} else {

				done = 1;

			}

		} else if ((buffer_uptodate(bh) || PageUptodate(page)) &&

			   (unmapped || startio)) {
@@ -931,7 +905,7 @@ xfs_page_state_convert( 
				 * was found, and we are in a path where we

				 * need to write the whole page out.

				 */

				if (!iomp) {

				if (!iomap_valid) {

					int	size;



					size = xfs_probe_unmapped_cluster(
@@ -939,21 +913,19 @@ xfs_page_state_convert( 
					err = xfs_map_blocks(inode, offset,

							size, &iomap,

							BMAPI_WRITE|BMAPI_MMAP);

					if (err) {

					if (err)

						goto error;

					iomap_valid = xfs_iomap_valid(&iomap,

								     offset);

				}

					iomp = xfs_offset_to_map(page, &iomap,

								     p_offset);

					done = (iomp == NULL);

				}

				if (iomp) {

					xfs_map_at_offset(page, bh, p_offset,

							inode->i_blkbits, iomp,

							ioend);

				if (iomap_valid) {

					xfs_map_at_offset(bh, offset,

							inode->i_blkbits,

							&iomap);

					if (startio) {

						xfs_add_to_ioend(inode,

							bh, p_offset, type,

							&ioend, done);

							&ioend, !iomap_valid);

					} else {

						set_buffer_dirty(bh);

						unlock_buffer(bh);
@@ -961,8 +933,6 @@ xfs_page_state_convert( 
					}

					page_dirty--;

					count++;

				} else {

					done = 1;

				}

			} else if (startio) {

				if (buffer_uptodate(bh) &&
@@ -970,14 +940,14 @@ xfs_page_state_convert( 
					ASSERT(buffer_mapped(bh));

					xfs_add_to_ioend(inode,

							bh, p_offset, type,

							&ioend, done);

							&ioend, !iomap_valid);

					page_dirty--;

					count++;

				} else {

					done = 1;

					iomap_valid = 0;

				}

			} else {

				done = 1;

				iomap_valid = 0;

			}

		}
@@ -992,11 +962,11 @@ xfs_page_state_convert( 
	if (startio)

		xfs_start_page_writeback(page, wbc, 1, count);



	if (ioend && iomp && !done) {

		offset = (iomp->iomap_offset + iomp->iomap_bsize - 1) >>

	if (ioend && iomap_valid) {

		offset = (iomap.iomap_offset + iomap.iomap_bsize - 1) >>

					PAGE_CACHE_SHIFT;

		tlast = min_t(pgoff_t, offset, last_index);

		xfs_cluster_write(inode, page->index + 1, iomp, &ioend,

		xfs_cluster_write(inode, page->index + 1, &iomap, &ioend,

					wbc, startio, unmapped, tlast);

	}

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