In btrfs, blocksize, the basic IO size of the filesystem, has been more than PAGE_SIZE. But, some 64 bit architures, like PPC64 and ARM64 have the default PAGE_SIZE as 64K, which means the filesystems handled in these architectures are with a blocksize of 64K. This works fine as long as you create and use the filesystems within these systems. In other words, one cannot create a filesystem in some other architecture and use that filesystem in PPC64 or ARM64, and vice versa., Another restriction is that we cannot use ext? filesystems in these architectures as btrfs filesystems, since ext? filesystems have a blocksize of 4K. Sometime last year, Wade Cline posted a patch(http://lwn.net/Articles/529682/). I started testing it, and found many locking/race issues. So, I changed the logic and created an extent_buffer_head that holds an array of extent buffers that belong to a page. There are few wrinkles in this patchset, like some xfstests are failing, which could be due to me doing something incorrectly w.r.t how the blocksize and PAGE_SIZE are used in these patched. Would like to get some feedback, review comments. Thanks, Chandra --- Chandra Seetharaman (7): btrfs: subpagesize-blocksize: Define extent_buffer_head btrfs: subpagesize-blocksize: Use a global alignment for size btrfs: subpagesize-blocksize: Handle small extent maps properly btrfs: subpagesize-blocksize: Handle iosize properly in submit_extent_page() btrfs: subpagesize-blocksize: handle checksum calculations properly btrfs: subpagesize-blocksize: Handle relocation clusters appropriately btrfs: subpagesize-blocksize: Allow mounting filesystems where sectorsize != PAGE_SIZE fs/btrfs/backref.c | 6 +- fs/btrfs/btrfs_inode.h | 7 + fs/btrfs/compression.c | 3 +- fs/btrfs/ctree.c | 2 +- fs/btrfs/ctree.h | 6 +- fs/btrfs/disk-io.c | 115 ++++++----- fs/btrfs/extent-tree.c | 18 +- fs/btrfs/extent_io.c | 449 ++++++++++++++++++++++++++----------------- fs/btrfs/extent_io.h | 55 ++++-- fs/btrfs/file-item.c | 45 ++++- fs/btrfs/file.c | 15 +- fs/btrfs/inode.c | 75 +++++--- fs/btrfs/ioctl.c | 6 +- fs/btrfs/ordered-data.c | 2 +- fs/btrfs/relocation.c | 6 +- fs/btrfs/tree-log.c | 2 +- fs/btrfs/volumes.c | 2 +- include/trace/events/btrfs.h | 2 +- 18 files changed, 515 insertions(+), 301 deletions(-) -- 1.7.12.4 -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
