| Message ID | d0a60acec35353dd7ad535bdddec0907857f2dd6.1686028197.git.naohiro.aota@wdc.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | btrfs: fixes for reclaim | expand |
On Tue, Jun 6, 2023 at 7:21 AM Naohiro Aota <naota@elisp.net> wrote: > > When a filesystem is read-only, we cannot reclaim a block group as it > cannot rewrite the data. Just bail out in that case. > > Note that it can drop BGs in this case. As we did sb_start_write(), > read-only filesystem means we got a fatal error and forced read-only. There > is no chance to reclaim them again. > > Fixes: 18bb8bbf13c1 ("btrfs: zoned: automatically reclaim zones") > CC: stable@vger.kernel.org # 5.15+ > Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com> > --- > fs/btrfs/block-group.c | 11 +++++++++-- > 1 file changed, 9 insertions(+), 2 deletions(-) > > diff --git a/fs/btrfs/block-group.c b/fs/btrfs/block-group.c > index d5bba02167be..db9bee071434 100644 > --- a/fs/btrfs/block-group.c > +++ b/fs/btrfs/block-group.c > @@ -1794,8 +1794,15 @@ void btrfs_reclaim_bgs_work(struct work_struct *work) > } > spin_unlock(&bg->lock); > > - /* Get out fast, in case we're unmounting the filesystem */ > - if (btrfs_fs_closing(fs_info)) { > + /* > + * Get out fast, in case we're read-only or unmounting the > + * filesystem. It is OK to drop block groups from the list even > + * for the read-only case. As we did sb_start_write(), "mount -o > + * ro" won't happen and read-only FS means it is forced I think here you mean "mount -o remount,ro", just to be more clear. > + * read-only due to a fatal error. So, it never get back to get -> gets > + * read-write to let us reclaime again. reclaime -> reclaim Other than that, it looks good to me. Reviewed-by: Filipe Manana <fdmanana@suse.com> Thanks. > + */ > + if (btrfs_need_cleaner_sleep(fs_info)) { > up_write(&space_info->groups_sem); > goto next; > } > -- > 2.40.1 >
With Filipe's comments incorporated:
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
diff --git a/fs/btrfs/block-group.c b/fs/btrfs/block-group.c index d5bba02167be..db9bee071434 100644 --- a/fs/btrfs/block-group.c +++ b/fs/btrfs/block-group.c @@ -1794,8 +1794,15 @@ void btrfs_reclaim_bgs_work(struct work_struct *work) } spin_unlock(&bg->lock); - /* Get out fast, in case we're unmounting the filesystem */ - if (btrfs_fs_closing(fs_info)) { + /* + * Get out fast, in case we're read-only or unmounting the + * filesystem. It is OK to drop block groups from the list even + * for the read-only case. As we did sb_start_write(), "mount -o + * ro" won't happen and read-only FS means it is forced + * read-only due to a fatal error. So, it never get back to + * read-write to let us reclaime again. + */ + if (btrfs_need_cleaner_sleep(fs_info)) { up_write(&space_info->groups_sem); goto next; }
When a filesystem is read-only, we cannot reclaim a block group as it cannot rewrite the data. Just bail out in that case. Note that it can drop BGs in this case. As we did sb_start_write(), read-only filesystem means we got a fatal error and forced read-only. There is no chance to reclaim them again. Fixes: 18bb8bbf13c1 ("btrfs: zoned: automatically reclaim zones") CC: stable@vger.kernel.org # 5.15+ Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com> --- fs/btrfs/block-group.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-)