lkml.org 
[lkml]   [2011]   [Aug]   [20]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH] Btrfs: fix 64 bit divide problem
Date
This fixes a regression introduced by

cdcb725c05fe0cb71777c66ddc2445fedbbb3c59

In cases where we need to divide/multiply by 2 we should just left/right shift
respectively, and in cases where theres N number of devices use do_div. Also
make the counters u64 to match up with rw_devices. Thanks,

Signed-off-by: Josef Bacik <josef@redhat.com>
---
fs/btrfs/extent-tree.c | 12 +++++++-----
1 files changed, 7 insertions(+), 5 deletions(-)

diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 44a3107..99ab571 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -6727,9 +6727,9 @@ int btrfs_can_relocate(struct btrfs_root *root, u64 bytenr)
struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
struct btrfs_device *device;
u64 min_free;
+ u64 dev_min = 1;
+ u64 dev_nr = 0;
int index;
- int dev_nr = 0;
- int dev_min = 1;
int full = 0;
int ret = 0;

@@ -6788,14 +6788,16 @@ int btrfs_can_relocate(struct btrfs_root *root, u64 bytenr)
index = get_block_group_index(block_group);
if (index == 0) {
dev_min = 4;
- min_free /= 2;
+ /* Divide by 2 */
+ min_free >>= 1;
} else if (index == 1) {
dev_min = 2;
} else if (index == 2) {
- min_free *= 2;
+ /* Multiply by 2 */
+ min_free <<= 1;
} else if (index == 3) {
dev_min = fs_devices->rw_devices;
- min_free /= dev_min;
+ do_div(min_free, dev_min);
}

mutex_lock(&root->fs_info->chunk_mutex);
--
1.7.5.2


\
 
 \ /
  Last update: 2011-08-20 14:33    [W:0.042 / U:0.328 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site