From: Christoph Hellwig <hch@lst.de>
To: linux-xfs@vger.kernel.org, linux-fsdevel@vger.kernel.org,
linux-nvdimm@ml01.01.org
Cc: ross.zwisler@linux.intel.com
Subject: [PATCH 08/12] xfs: take the ilock shared if possible in xfs_file_iomap_begin
Date: Fri, 16 Sep 2016 13:27:10 +0200 [thread overview]
Message-ID: <1474025234-13804-9-git-send-email-hch@lst.de> (raw)
In-Reply-To: <1474025234-13804-1-git-send-email-hch@lst.de>
We always just read the extent first, and will later lock exlusively
after first dropping the lock in case we actually allocate blocks.
Signed-off-by: Christoph Hellwig <hch@lst.de>
---
fs/xfs/xfs_iomap.c | 10 ++++++----
1 file changed, 6 insertions(+), 4 deletions(-)
diff --git a/fs/xfs/xfs_iomap.c b/fs/xfs/xfs_iomap.c
index 5d06a2d..c3cc175 100644
--- a/fs/xfs/xfs_iomap.c
+++ b/fs/xfs/xfs_iomap.c
@@ -955,6 +955,7 @@ xfs_file_iomap_begin(
struct xfs_bmbt_irec imap;
xfs_fileoff_t offset_fsb, end_fsb;
int nimaps = 1, error = 0;
+ unsigned lockmode;
if (XFS_FORCED_SHUTDOWN(mp))
return -EIO;
@@ -964,7 +965,7 @@ xfs_file_iomap_begin(
iomap);
}
- xfs_ilock(ip, XFS_ILOCK_EXCL);
+ lockmode = xfs_ilock_data_map_shared(ip);
ASSERT(offset <= mp->m_super->s_maxbytes);
if ((xfs_fsize_t)offset + length > mp->m_super->s_maxbytes)
@@ -975,7 +976,7 @@ xfs_file_iomap_begin(
error = xfs_bmapi_read(ip, offset_fsb, end_fsb - offset_fsb, &imap,
&nimaps, XFS_BMAPI_ENTIRE);
if (error) {
- xfs_iunlock(ip, XFS_ILOCK_EXCL);
+ xfs_iunlock(ip, lockmode);
return error;
}
@@ -995,7 +996,8 @@ xfs_file_iomap_begin(
* xfs_iomap_write_direct() expects the shared lock. It
* is unlocked on return.
*/
- xfs_ilock_demote(ip, XFS_ILOCK_EXCL);
+ if (lockmode == XFS_ILOCK_EXCL)
+ xfs_ilock_demote(ip, lockmode);
error = xfs_iomap_write_direct(ip, offset, length, &imap,
nimaps);
if (error)
@@ -1006,7 +1008,7 @@ xfs_file_iomap_begin(
} else {
ASSERT(nimaps);
- xfs_iunlock(ip, XFS_ILOCK_EXCL);
+ xfs_iunlock(ip, lockmode);
trace_xfs_iomap_found(ip, offset, length, 0, &imap);
}
--
2.1.4
next prev parent reply other threads:[~2016-09-16 11:27 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-09-16 11:27 iomap based DAX path V3 Christoph Hellwig
2016-09-16 11:27 ` [PATCH 01/12] iomap: add IOMAP_F_NEW flag Christoph Hellwig
2016-09-16 11:27 ` [PATCH 02/12] iomap: expose iomap_apply outside iomap.c Christoph Hellwig
2016-09-16 11:27 ` [PATCH 03/12] dax: don't pass buffer_head to dax_insert_mapping Christoph Hellwig
2016-09-16 11:27 ` [PATCH 04/12] dax: don't pass buffer_head to copy_user_dax Christoph Hellwig
2016-09-16 11:27 ` [PATCH 05/12] dax: provide an iomap based dax read/write path Christoph Hellwig
2016-09-16 11:27 ` [PATCH 06/12] dax: provide an iomap based fault handler Christoph Hellwig
2016-09-16 11:27 ` [PATCH 07/12] xfs: fix locking for DAX writes Christoph Hellwig
2016-09-16 11:27 ` Christoph Hellwig [this message]
2016-09-16 11:27 ` [PATCH 09/12] xfs: refactor xfs_setfilesize Christoph Hellwig
2016-09-16 11:27 ` [PATCH 10/12] xfs: use iomap to implement DAX Christoph Hellwig
2016-09-16 11:27 ` [PATCH 11/12] ext2: stop passing buffer_head to ext2_get_blocks Christoph Hellwig
2016-09-16 11:27 ` [PATCH 12/12] ext2: use iomap to implement DAX Christoph Hellwig
2016-09-26 14:49 ` Jan Kara
-- strict thread matches above, loose matches on Subject: below --
2016-09-14 10:01 iomap based DAX path V2 Christoph Hellwig
2016-09-14 10:01 ` [PATCH 08/12] xfs: take the ilock shared if possible in xfs_file_iomap_begin Christoph Hellwig
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