This patch set adds support for dax on the BTRFS filesystem. In order to support for CoW for btrfs, there were changes which had to be made to the dax handling. The important one is copying blocks into the same dax device before using them which is performed by iomap type IOMAP_DAX_COW. Snapshotting and CoW features are supported (including mmap preservation across snapshots). Git: https://github.com/goldwynr/linux/tree/btrfs-dax Changes since v2: - Created a new type IOMAP_DAX_COW as opposed to flag IOMAP_F_COW - CoW source address is presented in iomap.inline_data - Split the patches to more elaborate dax/iomap patches Changes since v1: - use iomap instead of redoing everything in btrfs - support for mmap writeprotecting on snapshotting fs/btrfs/Makefile | 1 fs/btrfs/ctree.h | 38 +++++ fs/btrfs/dax.c | 288 +++++++++++++++++++++++++++++++++++++++++-- fs/btrfs/disk-io.c | 4 fs/btrfs/file.c | 37 ++++- fs/btrfs/inode.c | 114 ++++++++++++----- fs/btrfs/ioctl.c | 29 +++- fs/btrfs/send.c | 4 fs/btrfs/super.c | 30 ++++ fs/dax.c | 152 ++++++++++++++++++++-- fs/iomap.c | 9 - fs/ocfs2/file.c | 2 fs/read_write.c | 10 - fs/xfs/xfs_reflink.c | 2 include/linux/dax.h | 13 + include/linux/fs.h | 7 - include/linux/iomap.h | 7 + include/trace/events/btrfs.h | 56 ++++++++ 18 files changed, 717 insertions(+), 86 deletions(-) -- Goldwyn
