[07/12] fs: btrfs: Use ktime_get_real_ts for root ctime

Submitted by Deepa Dinamani on April 8, 2017, 12:57 a.m.

Details

Message ID 1491613030-11599-8-git-send-email-deepa.kernel@gmail.com
State New
Headers show

Commit Message

Deepa Dinamani April 8, 2017, 12:57 a.m.
btrfs_root_item maintains the ctime for root updates.
This is not part of vfs_inode.

Since current_time() uses struct inode* as an argument
as Linus suggested, this cannot be used to update root
times unless, we modify the signature to use inode.

Since btrfs uses nanosecond time granularity, it can also
use ktime_get_real_ts directly to obtain timestamp for
the root. It is necessary to use the timespec time api
here because the same btrfs_set_stack_timespec_*() apis
are used for vfs inode times as well. These can be
transitioned to using timespec64 when btrfs internally
changes to use timespec64 as well.

Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Acked-by: David Sterba <dsterba@suse.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
---
 fs/btrfs/root-tree.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

Comments

David Sterba April 12, 2017, 1:42 p.m.
On Fri, Apr 07, 2017 at 05:57:05PM -0700, Deepa Dinamani wrote:
> btrfs_root_item maintains the ctime for root updates.
> This is not part of vfs_inode.
> 
> Since current_time() uses struct inode* as an argument
> as Linus suggested, this cannot be used to update root
> times unless, we modify the signature to use inode.
> 
> Since btrfs uses nanosecond time granularity, it can also
> use ktime_get_real_ts directly to obtain timestamp for
> the root. It is necessary to use the timespec time api
> here because the same btrfs_set_stack_timespec_*() apis
> are used for vfs inode times as well. These can be
> transitioned to using timespec64 when btrfs internally
> changes to use timespec64 as well.
> 
> Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
> Acked-by: David Sterba <dsterba@suse.com>
> Reviewed-by: Arnd Bergmann <arnd@arndb.de>

I'm going to add the patch to my 4.12 queue and will let Andrew know.

Patch hide | download patch | download mbox

diff --git a/fs/btrfs/root-tree.c b/fs/btrfs/root-tree.c
index a08224e..7d6bc30 100644
--- a/fs/btrfs/root-tree.c
+++ b/fs/btrfs/root-tree.c
@@ -501,8 +501,9 @@  void btrfs_update_root_times(struct btrfs_trans_handle *trans,
 			     struct btrfs_root *root)
 {
 	struct btrfs_root_item *item = &root->root_item;
-	struct timespec ct = current_fs_time(root->fs_info->sb);
+	struct timespec ct;
 
+	ktime_get_real_ts(&ct);
 	spin_lock(&root->root_item_lock);
 	btrfs_set_root_ctransid(item, trans->transid);
 	btrfs_set_stack_timespec_sec(&item->ctime, ct.tv_sec);