Eric Lee / linux-smarc-t335x-v3.2

Download as
Browse Code ยป

Commit 6719db6a23d4b7f1e5052eedae394135e3aef9c1

Authored by Josef Bacik
Committed by Linus Torvalds
1 parent c063d8a60f
Exists in master and in 4 other branches v3.2_AM335xPSP_04.06.00.11, v3.2_NEWT335xPSP_04.06.00.11, v3.2_SBC_SMARTMEN, v3.2_SMARCT335xPSP_04.06.00.11

Btrfs: fix 64 bit divide problem 

This fixes a regression introduced by commit cdcb725c05fe ("Btrfs: check
if there is enough space for balancing smarter").  We can't do 64-bit
divides on 32-bit architectures.

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>
Acked-and-tested-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Showing 1 changed file with 7 additions and 5 deletions Side-by-side Diff

fs/btrfs/extent-tree.c
Diff comments   View file @ 6719db6
... ... @@ -6735,9 +6735,9 @@
6735 6735 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
6736 6736 struct btrfs_device *device;
6737 6737 u64 min_free;
  6738 + u64 dev_min = 1;
  6739 + u64 dev_nr = 0;
6738 6740 int index;
6739   - int dev_nr = 0;
6740   - int dev_min = 1;
6741 6741 int full = 0;
6742 6742 int ret = 0;
6743 6743  
6744 6744  
6745 6745  
... ... @@ -6796,14 +6796,16 @@
6796 6796 index = get_block_group_index(block_group);
6797 6797 if (index == 0) {
6798 6798 dev_min = 4;
6799   - min_free /= 2;
  6799 + /* Divide by 2 */
  6800 + min_free >>= 1;
6800 6801 } else if (index == 1) {
6801 6802 dev_min = 2;
6802 6803 } else if (index == 2) {
6803   - min_free *= 2;
  6804 + /* Multiply by 2 */
  6805 + min_free <<= 1;
6804 6806 } else if (index == 3) {
6805 6807 dev_min = fs_devices->rw_devices;
6806   - min_free /= dev_min;
  6808 + do_div(min_free, dev_min);
6807 6809 }
6808 6810  
6809 6811 mutex_lock(&root->fs_info->chunk_mutex);