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authorZygo Blaxell <ce3g8jdj@umail.furryterror.org>2019-09-12 19:55:01 -0400
committerPaul Gortmaker <paul.gortmaker@windriver.com>2019-11-09 19:33:47 -0500
commit810f5770978a8ce9ea641976beec50f23806c8d2 (patch)
parent7816678e39346a9736e6923f7831d5d49c63a8d0 (diff)
btrfs: fix balance convert to single on 32-bit host CPUs
commit 7a54789074a54f64addf5b49bf1994f478337a83 upstream. Currently, the command: btrfs balance start -dconvert=single,soft . on a Raspberry Pi produces the following kernel message: BTRFS error (device mmcblk0p2): balance: invalid convert data profile single This fails because we use is_power_of_2(unsigned long) to validate the new data profile, the constant for 'single' profile uses bit 48, and there are only 32 bits in a long on ARM. Fix by open-coding the check using u64 variables. Tested by completing the original balance command on several Raspberry Pis. Fixes: 818255feece6 ("btrfs: use common helper instead of open coding a bit test") CC: stable@vger.kernel.org # 4.20+ Signed-off-by: Zygo Blaxell <ce3g8jdj@umail.furryterror.org> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
1 files changed, 5 insertions, 1 deletions
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 8508f6028c8d..4075b1b95105 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -3857,7 +3857,11 @@ static int alloc_profile_is_valid(u64 flags, int extended)
return !extended; /* "0" is valid for usual profiles */
/* true if exactly one bit set */
- return is_power_of_2(flags);
+ /*
+ * Don't use is_power_of_2(unsigned long) because it won't work
+ * for the single profile (1ULL << 48) on 32-bit CPUs.
+ */
+ return flags != 0 && (flags & (flags - 1)) == 0;
static inline int balance_need_close(struct btrfs_fs_info *fs_info)