From: Dave Chinner <david@fromorbit.com>
To: xfs@oss.sgi.com
Subject: [PATCH 30/36] libxfs: work around do_div() not handling 32 bit numerators
Date: Wed, 13 Nov 2013 17:40:54 +1100 [thread overview]
Message-ID: <1384324860-25677-31-git-send-email-david@fromorbit.com> (raw)
In-Reply-To: <1384324860-25677-1-git-send-email-david@fromorbit.com>
From: Dave Chinner <dchinner@redhat.com>
The libxfs dquot buffer code uses do_div() with a 32 bit numerator.
This gives incorrect results as do_div() passes the numerator by
reference as a pointer to a 64 bit value. Hence it does the division
using 32 bits of garbage gives the wrong result.
As per Christoph's suggestion, we can kill the usage of do_div()
here completely and just do the division directly, both in userspace
and kernel space.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
---
libxfs/xfs_dquot_buf.c | 7 +------
1 file changed, 1 insertion(+), 6 deletions(-)
diff --git a/libxfs/xfs_dquot_buf.c b/libxfs/xfs_dquot_buf.c
index 620d9d3..6bbb0ff 100644
--- a/libxfs/xfs_dquot_buf.c
+++ b/libxfs/xfs_dquot_buf.c
@@ -23,13 +23,8 @@ xfs_calc_dquots_per_chunk(
struct xfs_mount *mp,
unsigned int nbblks) /* basic block units */
{
- unsigned int ndquots;
-
ASSERT(nbblks > 0);
- ndquots = BBTOB(nbblks);
- do_div(ndquots, sizeof(xfs_dqblk_t));
-
- return ndquots;
+ return BBTOB(nbblks) / sizeof(xfs_dqblk_t);
}
/*
--
1.8.4.rc3
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next prev parent reply other threads:[~2013-11-13 6:41 UTC|newest]
Thread overview: 45+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-11-13 6:40 [PATCH 00/36 V5] xfsprogs: CRC write support for xfs_db + Dave Chinner
2013-11-13 6:40 ` [PATCH 01/36] xfsprogs: fix automatic dependency generation Dave Chinner
2013-11-13 6:40 ` [PATCH 02/36] xfs: fix some minor sparse warnings Dave Chinner
2013-11-13 6:40 ` [PATCH 03/36] xfs: create a shared header file for format-related information Dave Chinner
2013-11-13 6:40 ` [PATCH 04/36] xfs: split dquot buffer operations out Dave Chinner
2013-11-13 6:40 ` [PATCH 05/36] xfs: decouple inode and bmap btree header files Dave Chinner
2013-11-13 6:40 ` [PATCH 06/36] libxfs: unify xfs_btree.c with kernel code Dave Chinner
2013-11-13 6:40 ` [PATCH 07/36] libxfs: bmap btree owner swap support Dave Chinner
2013-11-13 6:40 ` [PATCH 08/36] libxfs: xfs_rtalloc.c becomes xfs_rtbitmap.c Dave Chinner
2013-11-13 6:40 ` [PATCH 09/36] libxfs: bring across inode buffer readahead verifier changes Dave Chinner
2013-11-13 6:40 ` [PATCH 10/36] libxfs: Minor cleanup and bug fix sync Dave Chinner
2013-11-13 6:40 ` [PATCH 11/36] xfs: remove newlines from strings passed to __xfs_printk Dave Chinner
2013-11-13 6:40 ` [PATCH 12/36] xfs: fix the wrong new_size/rnew_size at xfs_iext_realloc_direct() Dave Chinner
2013-11-13 6:40 ` [PATCH 13/36] xfs: fix node forward in xfs_node_toosmall Dave Chinner
2013-11-13 6:40 ` [PATCH 14/36] xfs: don't emit corruption noise on fs probes Dave Chinner
2013-11-13 6:40 ` [PATCH 15/36] libxfs: fix root inode handling inconsistencies Dave Chinner
2013-11-13 6:40 ` [PATCH 16/36] libxfs: stop caching inode structures Dave Chinner
2013-11-13 6:40 ` [PATCH 17/36] db: separate out straight buffer IO from map based IO Dave Chinner
2013-11-13 6:40 ` [PATCH 18/36] db: rewrite bbmap to use xfs_buf_map Dave Chinner
2013-11-13 6:40 ` [PATCH 19/36] libxfs: refactor libxfs_buf_read_map for xfs_db Dave Chinner
2013-11-13 6:40 ` [PATCH 20/36] db: rewrite IO engine to use libxfs Dave Chinner
2013-11-13 16:05 ` Christoph Hellwig
2013-11-13 6:40 ` [PATCH 21/36] db: introduce verifier support into set_cur Dave Chinner
2013-11-13 6:40 ` [PATCH 22/36] db: indicate if the CRC on a buffer is correct or not Dave Chinner
2013-11-13 6:40 ` [PATCH 23/36] db: verify and calculate inode CRCs Dave Chinner
2013-11-13 6:40 ` [PATCH 24/36] db: verify and calculate dquot CRCs Dave Chinner
2013-11-13 16:05 ` Christoph Hellwig
2013-11-13 6:40 ` [PATCH 25/36] db: add a special directory buffer verifier Dave Chinner
2013-11-13 6:40 ` [PATCH 26/36] db: add a special attribute " Dave Chinner
2013-11-13 6:40 ` [PATCH 27/36] db: re-enable write support for v5 filesystems Dave Chinner
2013-11-13 6:40 ` [PATCH 28/36] xfs_db: use inode cluster buffers for inode IO Dave Chinner
2013-11-13 6:40 ` [PATCH 29/36] xfs_db: avoid libxfs buffer lookup warnings Dave Chinner
2013-11-13 6:40 ` Dave Chinner [this message]
2013-11-13 6:40 ` [PATCH 31/36] db: enable metadump on CRC filesystems Dave Chinner
2013-11-13 16:09 ` Christoph Hellwig
2013-11-13 21:00 ` Dave Chinner
2013-11-14 13:34 ` Christoph Hellwig
2013-11-13 6:40 ` [PATCH 32/36] xfs: support larger inode clusters on v5 filesystems Dave Chinner
2013-11-13 6:40 ` [PATCH 33/36] xfsprogs: kill experimental warnings for " Dave Chinner
2013-11-13 6:40 ` [PATCH 34/36] repair: prefetching is turned off unnecessarily Dave Chinner
2013-11-13 6:40 ` [PATCH 35/36] repair: Increase default repair parallelism on large filesystems Dave Chinner
2013-11-13 16:10 ` Christoph Hellwig
2013-11-13 21:01 ` Dave Chinner
2013-11-13 6:41 ` [PATCH 36/36] repair: fix leaf node directory data check Dave Chinner
2013-11-14 16:18 ` [PATCH 00/36 V5] xfsprogs: CRC write support for xfs_db + Rich Johnston
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