Linux-Block Archive on lore.kernel.org
 help / color / Atom feed
From: Christoph Hellwig <hch@lst.de>
To: linux-xfs@vger.kernel.org
Cc: linux-fsdevel@vger.kernel.org, linux-block@vger.kernel.org,
	linux-mm@kvack.org
Subject: [PATCH 14/33] xfs: simplify xfs_bmap_punch_delalloc_range
Date: Wed,  9 May 2018 09:48:11 +0200
Message-ID: <20180509074830.16196-15-hch@lst.de> (raw)
In-Reply-To: <20180509074830.16196-1-hch@lst.de>

Instead of using xfs_bmapi_read to find delalloc extents and then punch
them out using xfs_bunmapi, opencode the loop to iterate over the extents
and call xfs_bmap_del_extent_delay directly.  This both simplifies the
code and reduces the number of extent tree lookups required.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 fs/xfs/xfs_bmap_util.c | 78 ++++++++++++++----------------------------
 1 file changed, 25 insertions(+), 53 deletions(-)

diff --git a/fs/xfs/xfs_bmap_util.c b/fs/xfs/xfs_bmap_util.c
index 8cd8c412f52d..7d2ba4cc8fba 100644
--- a/fs/xfs/xfs_bmap_util.c
+++ b/fs/xfs/xfs_bmap_util.c
@@ -695,12 +695,10 @@ xfs_getbmap(
 }
 
 /*
- * dead simple method of punching delalyed allocation blocks from a range in
- * the inode. Walks a block at a time so will be slow, but is only executed in
- * rare error cases so the overhead is not critical. This will always punch out
- * both the start and end blocks, even if the ranges only partially overlap
- * them, so it is up to the caller to ensure that partial blocks are not
- * passed in.
+ * Dead simple method of punching delalyed allocation blocks from a range in
+ * the inode.  This will always punch out both the start and end blocks, even
+ * if the ranges only partially overlap them, so it is up to the caller to
+ * ensure that partial blocks are not passed in.
  */
 int
 xfs_bmap_punch_delalloc_range(
@@ -708,63 +706,37 @@ xfs_bmap_punch_delalloc_range(
 	xfs_fileoff_t		start_fsb,
 	xfs_fileoff_t		length)
 {
-	xfs_fileoff_t		remaining = length;
+	struct xfs_ifork	*ifp = &ip->i_df;
+	struct xfs_bmbt_irec	got, del;
+	struct xfs_iext_cursor	icur;
 	int			error = 0;
 
 	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
 
-	do {
-		int		done;
-		xfs_bmbt_irec_t	imap;
-		int		nimaps = 1;
-		xfs_fsblock_t	firstblock;
-		struct xfs_defer_ops dfops;
+	if (!(ifp->if_flags & XFS_IFEXTENTS)) {
+		error = xfs_iread_extents(NULL, ip, XFS_DATA_FORK);
+		if (error)
+			return error;
+	}
 
-		/*
-		 * Map the range first and check that it is a delalloc extent
-		 * before trying to unmap the range. Otherwise we will be
-		 * trying to remove a real extent (which requires a
-		 * transaction) or a hole, which is probably a bad idea...
-		 */
-		error = xfs_bmapi_read(ip, start_fsb, 1, &imap, &nimaps,
-				       XFS_BMAPI_ENTIRE);
+	if (!xfs_iext_lookup_extent(ip, ifp, start_fsb, &icur, &got))
+		return 0;
 
-		if (error) {
-			/* something screwed, just bail */
-			if (!XFS_FORCED_SHUTDOWN(ip->i_mount)) {
-				xfs_alert(ip->i_mount,
-			"Failed delalloc mapping lookup ino %lld fsb %lld.",
-						ip->i_ino, start_fsb);
-			}
+	do {
+		if (got.br_startoff >= start_fsb + length)
 			break;
-		}
-		if (!nimaps) {
-			/* nothing there */
-			goto next_block;
-		}
-		if (imap.br_startblock != DELAYSTARTBLOCK) {
-			/* been converted, ignore */
-			goto next_block;
-		}
-		WARN_ON(imap.br_blockcount == 0);
+		if (!isnullstartblock(got.br_startblock))
+			continue;
 
-		/*
-		 * Note: while we initialise the firstblock/dfops pair, they
-		 * should never be used because blocks should never be
-		 * allocated or freed for a delalloc extent and hence we need
-		 * don't cancel or finish them after the xfs_bunmapi() call.
-		 */
-		xfs_defer_init(&dfops, &firstblock);
-		error = xfs_bunmapi(NULL, ip, start_fsb, 1, 0, 1, &firstblock,
-					&dfops, &done);
+		del = got;
+		xfs_trim_extent(&del, start_fsb, length);
+		error = xfs_bmap_del_extent_delay(ip, XFS_DATA_FORK, &icur,
+				&got, &del);
 		if (error)
 			break;
-
-		ASSERT(!xfs_defer_has_unfinished_work(&dfops));
-next_block:
-		start_fsb++;
-		remaining--;
-	} while(remaining > 0);
+		if (!xfs_iext_get_extent(ifp, &icur, &got))
+			break;
+	} while (xfs_iext_next_extent(ifp, &icur, &got));
 
 	return error;
 }
-- 
2.17.0

  parent reply index

Thread overview: 64+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-05-09  7:47 stop using buffer heads in xfs and iomap Christoph Hellwig
2018-05-09  7:47 ` [PATCH 01/33] block: add a lower-level bio_add_page interface Christoph Hellwig
2018-05-09 15:12   ` Matthew Wilcox
2018-05-10  6:40     ` Christoph Hellwig
2018-05-10 21:49       ` Andreas Dilger
2018-05-11  6:29         ` Christoph Hellwig
2018-05-15 16:47           ` Jens Axboe
2018-05-10  8:52   ` Ming Lei
2018-05-11  6:24     ` Christoph Hellwig
2018-05-16  5:06   ` Ritesh Harjani
2018-05-16 18:05     ` Christoph Hellwig
2018-05-17  4:18       ` Ritesh Harjani
2018-05-09  7:47 ` [PATCH 02/33] fs: factor out a __generic_write_end helper Christoph Hellwig
2018-05-09 15:15   ` Matthew Wilcox
2018-05-10  6:40     ` Christoph Hellwig
2018-05-09  7:48 ` [PATCH 03/33] fs: move page_cache_seek_hole_data to iomap.c Christoph Hellwig
2018-05-09  7:48 ` [PATCH 04/33] fs: remove the buffer_unwritten check in page_seek_hole_data Christoph Hellwig
2018-05-17 11:33   ` Andreas Grünbacher
2018-05-09  7:48 ` [PATCH 05/33] fs: use ->is_partially_uptodate in page_cache_seek_hole_data Christoph Hellwig
2018-05-09  7:48 ` [PATCH 06/33] mm: give the 'ret' variable a better name __do_page_cache_readahead Christoph Hellwig
2018-05-09 15:45   ` Matthew Wilcox
2018-05-10  6:41     ` Christoph Hellwig
2018-05-09  7:48 ` [PATCH 07/33] mm: split ->readpages calls to avoid non-contiguous pages lists Christoph Hellwig
2018-05-09 15:46   ` Matthew Wilcox
2018-05-09  7:48 ` [PATCH 08/33] iomap: use __bio_add_page in iomap_dio_zero Christoph Hellwig
2018-05-09  7:48 ` [PATCH 09/33] iomap: add a iomap_sector helper Christoph Hellwig
2018-05-09  7:48 ` [PATCH 10/33] iomap: add an iomap-based bmap implementation Christoph Hellwig
2018-05-09 16:46   ` Darrick J. Wong
2018-05-10  6:42     ` Christoph Hellwig
2018-05-10 15:08       ` Darrick J. Wong
2018-05-11  6:25         ` Christoph Hellwig
2018-05-12  1:56           ` Darrick J. Wong
2018-05-09  7:48 ` [PATCH 11/33] iomap: add an iomap-based readpage and readpages implementation Christoph Hellwig
2018-05-10  1:17   ` Dave Chinner
2018-05-10  6:44     ` Christoph Hellwig
2018-05-09  7:48 ` [PATCH 12/33] xfs: use iomap_bmap Christoph Hellwig
2018-05-09  7:48 ` [PATCH 13/33] xfs: use iomap for blocksize == PAGE_SIZE readpage and readpages Christoph Hellwig
2018-05-09  7:48 ` Christoph Hellwig [this message]
2018-05-09  7:48 ` [PATCH 15/33] xfs: simplify xfs_aops_discard_page Christoph Hellwig
2018-05-09  7:48 ` [PATCH 16/33] xfs: move locking into xfs_bmap_punch_delalloc_range Christoph Hellwig
2018-05-09  7:48 ` [PATCH 17/33] xfs: make xfs_writepage_map extent map centric Christoph Hellwig
2018-05-09  7:48 ` [PATCH 18/33] xfs: remove the now unused XFS_BMAPI_IGSTATE flag Christoph Hellwig
2018-05-09  7:48 ` [PATCH 19/33] xfs: remove xfs_reflink_find_cow_mapping Christoph Hellwig
2018-05-09  7:48 ` [PATCH 20/33] xfs: remove xfs_reflink_trim_irec_to_next_cow Christoph Hellwig
2018-05-09  7:48 ` [PATCH 21/33] xfs: simplify xfs_map_blocks by using xfs_iext_lookup_extent directly Christoph Hellwig
2018-05-09  7:48 ` [PATCH 22/33] xfs: don't clear imap_valid for a non-uptodate buffers Christoph Hellwig
2018-05-09  7:48 ` [PATCH 23/33] xfs: remove the imap_valid flag Christoph Hellwig
2018-05-09  7:48 ` [PATCH 24/33] xfs: don't look at buffer heads in xfs_add_to_ioend Christoph Hellwig
2018-05-09  7:48 ` [PATCH 25/33] xfs: move all writeback buffer_head manipulation into xfs_map_at_offset Christoph Hellwig
2018-05-09  7:48 ` [PATCH 26/33] xfs: allow writeback on pages without buffer heads Christoph Hellwig
2018-05-09  7:48 ` [PATCH 27/33] xfs: remove xfs_start_page_writeback Christoph Hellwig
2018-05-09  7:48 ` [PATCH 28/33] xfs: refactor the tail of xfs_writepage_map Christoph Hellwig
2018-05-09  7:48 ` [PATCH 29/33] xfs: do not set the page uptodate in xfs_writepage_map Christoph Hellwig
2018-05-09  7:48 ` [PATCH 30/33] iomap: add initial support for writes without buffer heads Christoph Hellwig
2018-05-09  7:48 ` [PATCH 31/33] iomap: add support for sub-pagesize buffered I/O " Christoph Hellwig
2018-05-14 16:00   ` Goldwyn Rodrigues
2018-05-15  7:26     ` Christoph Hellwig
2018-05-15 13:47       ` Goldwyn Rodrigues
2018-05-16  5:46         ` Dave Chinner
2018-05-09  7:48 ` [PATCH 32/33] xfs: add support for sub-pagesize writeback without buffer_heads Christoph Hellwig
2018-05-09  7:48 ` [PATCH 33/33] fs: remove __block_write_begin and iomap_to_bh Christoph Hellwig
2018-05-10 15:13 ` stop using buffer heads in xfs and iomap Darrick J. Wong
2018-05-11  6:22   ` Christoph Hellwig
2018-05-11  6:39     ` Darrick J. Wong

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20180509074830.16196-15-hch@lst.de \
    --to=hch@lst.de \
    --cc=linux-block@vger.kernel.org \
    --cc=linux-fsdevel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=linux-xfs@vger.kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

Linux-Block Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/linux-block/0 linux-block/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 linux-block linux-block/ https://lore.kernel.org/linux-block \
		linux-block@vger.kernel.org
	public-inbox-index linux-block

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.kernel.vger.linux-block


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git