On Wed, 16 Apr 2014, Dave Chinner wrote: > Date: Wed, 16 Apr 2014 08:02:20 +1000 > From: Dave Chinner <david@xxxxxxxxxxxxx> > To: Lukas Czerner <lczerner@xxxxxxxxxx> > Cc: linux-fsdevel@xxxxxxxxxxxxxxx, linux-ext4@xxxxxxxxxxxxxxx, xfs@xxxxxxxxxxx > Subject: Re: [PATCH 2/3 v2] fs: Prevent doing FALLOC_FL_ZERO_RANGE on append > only file > > On Tue, Apr 15, 2014 at 06:41:15PM +0200, Lukas Czerner wrote: > > Currently punch hole and collapse range fallocate operation are not > > allowed on append only file. This should be case for zero range as well. > > Fix it by allowing only pure fallocate (possibly with keep size set). > > > > Signed-off-by: Lukas Czerner <lczerner@xxxxxxxxxx> > > --- > > v2: Change the condition to be future proof as suggested by hch > > > > fs/open.c | 6 ++---- > > 1 file changed, 2 insertions(+), 4 deletions(-) > > > > diff --git a/fs/open.c b/fs/open.c > > index 631aea81..fe48b2f 100644 > > --- a/fs/open.c > > +++ b/fs/open.c > > @@ -254,11 +254,9 @@ int do_fallocate(struct file *file, int mode, loff_t offset, loff_t len) > > return -EBADF; > > > > /* > > - * It's not possible to punch hole or perform collapse range > > - * on append only file > > + * We can only allow pure fallocate on append only files > > */ > > - if (mode & (FALLOC_FL_PUNCH_HOLE | FALLOC_FL_COLLAPSE_RANGE) > > - && IS_APPEND(inode)) > > + if (mode & ~FALLOC_FL_KEEP_SIZE && IS_APPEND(inode)) > > if ((mode & ~FALLOC_FL_KEEP_SIZE) && IS_APPEND(inode)) > > gcc normally complains when you mix & and && in the same logic > statement without () to separate the logic. I agree with gcc here, > because the () indicate the intent of the logic and make it easy to > determine that the & and && haven't been mixed up or fat-fingered... Yeah, I was thinking about this and then left it to operator precedence. But having () in there is fine as well. -Lukas > > Cheers, > > Dave. > -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
