| Message ID | 53D1DCB4.8090409@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 07/25/2014 12:27 PM, Eric Sandeen wrote: > make_btrfs() rounds down the first device size to a multiple of sectorsize: > > num_bytes = (num_bytes / sectorsize) * sectorsize; > > but subsequent device adds don't. > > This seems a bit odd & inconsistent, and it makes xfstest btrfs/011 > _notrun(), because it explicitly checks that devices are the same size. > > I don't know that there is anything inherently wrong with having > a few device bytes extend past the last block, but to be consistent, > it seems like btrfs_add_to_fsid() should round the size in the same > way. > > And now btrfs/011 runs more consistently; the test devices don't > have to be sectorsize multiples in order for all mkfs'd device > sizes to match. > Signed-off-by: Eric Sandeen <sandeen@redhat.com> > --- > > ideally this might go into btrfs_device_size(), but we don't have > the chosen sector size anywhere near there... > > diff --git a/utils.c b/utils.c > index e130849..4d7ee35 100644 > --- a/utils.c > +++ b/utils.c > @@ -554,7 +554,7 @@ int btrfs_add_to_fsid(struct btrfs_trans_handle *trans, > device->sector_size = sectorsize; > device->fd = fd; > device->writeable = 1; > - device->total_bytes = block_count; > + device->total_bytes = (block_count / sectorsize) * sectorsize; > device->bytes_used = 0; > device->total_ios = 0; > device->dev_root = root->fs_info->dev_root; its better to do this at the function btrfs_prepare_device() itself, so that it would include first and the rest added. or we need to apply this on the block_count instead, as we do add that to the total_bytes. Thanks, Anand > -- > To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Thu, Jul 24, 2014 at 11:27:32PM -0500, Eric Sandeen wrote: > make_btrfs() rounds down the first device size to a multiple of sectorsize: ^^^^^^^^^^^ > - device->total_bytes = block_count; > + device->total_bytes = (block_count / sectorsize) * sectorsize; kerncompat.h:#define round_down(x, y) ((x) & ~__round_mask(x, y)) - z -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 7/25/14, 12:12 PM, Zach Brown wrote: > On Thu, Jul 24, 2014 at 11:27:32PM -0500, Eric Sandeen wrote: >> make_btrfs() rounds down the first device size to a multiple of sectorsize: > > ^^^^^^^^^^^ > >> - device->total_bytes = block_count; >> + device->total_bytes = (block_count / sectorsize) * sectorsize; > > kerncompat.h:#define round_down(x, y) ((x) & ~__round_mask(x, y)) > > - z > yeah yeah ;) this isn't copied kernel code but sure, that'd be better. I'm trying to clean up this whole "we say blocks when we mean bytes!" thing, and I'll include round_down() as well. Thanks, -Eric -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 7/25/14, 12:25 PM, Eric Sandeen wrote: > On 7/25/14, 12:12 PM, Zach Brown wrote: >> On Thu, Jul 24, 2014 at 11:27:32PM -0500, Eric Sandeen wrote: >>> make_btrfs() rounds down the first device size to a multiple of sectorsize: >> >> ^^^^^^^^^^^ >> >>> - device->total_bytes = block_count; >>> + device->total_bytes = (block_count / sectorsize) * sectorsize; >> >> kerncompat.h:#define round_down(x, y) ((x) & ~__round_mask(x, y)) >> >> - z >> > > yeah yeah ;) this isn't copied kernel code but sure, that'd be better. > > I'm trying to clean up this whole "we say blocks when we mean bytes!" > thing, and I'll include round_down() as well. meh. And half this is done in kernelspace for device add/replace (device size setting etc) so TBH I'm increasingly inclined to just back away slowly here. :( (IOWs device_add calls btrfs_prepare_device(), but the size it finds is never used; the kernel does: device->total_bytes = i_size_read(bdev->bd_inode); so changing prepare_device doesn't catch add/replace cases...) Perhaps the simpler option is to remove the rounding which is only done on the first device added in userspace, but I honestly don't know what the design plan is, or what the ramifications of that might be ... -Eric -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/utils.c b/utils.c index e130849..4d7ee35 100644 --- a/utils.c +++ b/utils.c @@ -554,7 +554,7 @@ int btrfs_add_to_fsid(struct btrfs_trans_handle *trans, device->sector_size = sectorsize; device->fd = fd; device->writeable = 1; - device->total_bytes = block_count; + device->total_bytes = (block_count / sectorsize) * sectorsize; device->bytes_used = 0; device->total_ios = 0; device->dev_root = root->fs_info->dev_root;
make_btrfs() rounds down the first device size to a multiple of sectorsize: num_bytes = (num_bytes / sectorsize) * sectorsize; but subsequent device adds don't. This seems a bit odd & inconsistent, and it makes xfstest btrfs/011 _notrun(), because it explicitly checks that devices are the same size. I don't know that there is anything inherently wrong with having a few device bytes extend past the last block, but to be consistent, it seems like btrfs_add_to_fsid() should round the size in the same way. And now btrfs/011 runs more consistently; the test devices don't have to be sectorsize multiples in order for all mkfs'd device sizes to match. Signed-off-by: Eric Sandeen <sandeen@redhat.com> --- ideally this might go into btrfs_device_size(), but we don't have the chosen sector size anywhere near there... -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html