lkml.org 
[lkml]   [2021]   [Jun]   [11]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    SubjectRe: [PATCH] fs: btrfs: Disable BTRFS on platforms having 256K pages
    From
    Date


    On 2021/6/10 下午1:23, Christophe Leroy wrote:
    > With a config having PAGE_SIZE set to 256K, BTRFS build fails
    > with the following message
    >
    > include/linux/compiler_types.h:326:38: error: call to '__compiletime_assert_791' declared with attribute error: BUILD_BUG_ON failed: (BTRFS_MAX_COMPRESSED % PAGE_SIZE) != 0
    >
    > BTRFS_MAX_COMPRESSED being 128K, BTRFS cannot support platforms with
    > 256K pages at the time being.
    >
    > There are two platforms that can select 256K pages:
    > - hexagon
    > - powerpc
    >
    > Disable BTRFS when 256K page size is selected.
    >
    > Reported-by: kernel test robot <lkp@intel.com>
    > Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
    > ---
    > fs/btrfs/Kconfig | 2 ++
    > 1 file changed, 2 insertions(+)
    >
    > diff --git a/fs/btrfs/Kconfig b/fs/btrfs/Kconfig
    > index 68b95ad82126..520a0f6a7d9e 100644
    > --- a/fs/btrfs/Kconfig
    > +++ b/fs/btrfs/Kconfig
    > @@ -18,6 +18,8 @@ config BTRFS_FS
    > select RAID6_PQ
    > select XOR_BLOCKS
    > select SRCU
    > + depends on !PPC_256K_PAGES # powerpc
    > + depends on !PAGE_SIZE_256KB # hexagon

    I'm OK to disable page size other than 4K, 16K, 32K, 64K for now.

    Although for other reasons.

    Not only for the BUILD_BUG_ON(), but for the fact that btrfs only
    support 4K, 16K, 32K, 64K sectorsize, and requires PAGE_SIZE == sectorsize.

    Although we're adding subpage support, the subpage support only comes
    with 4K sectorsize on 64K page size.

    Until variable length version is introduced, 256K/128K page size won't
    be support.

    Thus I'm fine to disable BTRFS for any arch outside of the supported
    page sizes for now.

    Thanks,
    Qu
    >
    > help
    > Btrfs is a general purpose copy-on-write filesystem with extents,
    >

    \
     
     \ /
      Last update: 2021-06-11 15:49    [W:4.142 / U:0.196 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site