On 21.09.20 г. 17:43 ч., Goldwyn Rodrigues wrote: > From: Goldwyn Rodrigues <rgoldwyn@xxxxxxxx> > > fs_info->fs_state is a filesystem bit check as opposed to inode > and can be performed before we begin with write checks. This eliminates > inode lock/unlock in case of error bit is set. > > Signed-off-by: Goldwyn Rodrigues <rgoldwyn@xxxxxxxx> > --- > fs/btrfs/file.c | 21 +++++++++------------ > 1 file changed, 9 insertions(+), 12 deletions(-) > > diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c > index 4c40a2742aab..ca374cb5ffc9 100644 > --- a/fs/btrfs/file.c > +++ b/fs/btrfs/file.c > @@ -1981,6 +1981,15 @@ static ssize_t btrfs_file_write_iter(struct kiocb *iocb, > size_t count; > loff_t oldsize; > > + /* > + * If BTRFS flips readonly due to some impossible error > + * (fs_info->fs_state now has BTRFS_SUPER_FLAG_ERROR), > + * although we have opened a file as writable, we have > + * to stop this write operation to ensure FS consistency. > + */ > + if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state)) > + return -EROFS; > + nit: Actually can't this check be eliminated altogether or the comment vastly simplified because BTRFS_SUPER_FLAG_ERROR check is performed only during mount so the description in the parantheses is invalid i.e the fs won't flip to RO because BTRFS_SUPER_FLAG_ERROR is now set in the super block. As a matter of fact how is this flag set - because I don't see it set in the kernel code nor in btrfs-progs ? <snip>
