On Mon, 17 Feb 2014 12:04:52 +0100, Andreas Rohner wrote: > On 2014-02-17 11:42, Ryusuke Konishi wrote: >> On Mon, 17 Feb 2014 10:06:56 +0100, Andreas Rohner wrote: >>> Hi Ryusuke, >>> >>> On 2014-02-17 04:00, Ryusuke Konishi wrote: >>>>> + segnum >= nilfs->ns_nsegments || >>>> >>>> This is bad too, because userland programs usually don't know the >>>> segment structure of NILFS. When we specify the partition size to >>>> range->len, FITRIM can fail due to this check. >>>> >>>> The upper limit of (range->start + range->len) should be >>>> the block device size. >>> >>> ext4 also checks the range structure like that. Besides couldn't it be >>> possible, that the block device is bigger than the file system? >> >> As I mentioned in my second mail, I misunderstood the meaning of this >> check at first. >> >> As you pointed out, the block device size may be bigger than the file >> system size after shrinking the file system. So, sbp->s_dev_size >> should be used for for this check. But it is a bit complicated since >> the current nilfs object doesn't have on-memory copy of it. >> >> It is OK to use nilfs->ns_nsegments as its alternative. > > Ok, just to be clear. According to your second mail it should look > something like this in nilfs_sufile_trim_fs(): > > if (segnum >= nilfs->ns_nsegments) > goto out; > > And in nilfs_ioctl_trim_fs(): > > if (range.len < nilfs->ns_blocksize || > range.start >= (nilfs->ns_nsegments * > nilfs->ns_blocks_per_segment) << > nilfs->ns_blocksize_bits) > return -EINVAL; > > > Is that correct? Yes, exactly. Regards, Ryusuke Konishi -- To unsubscribe from this list: send the line "unsubscribe linux-nilfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
