Towards supporing write-hints/streams for filesystem journal. Here is the v1 patch for background - https://marc.info/?l=linux-fsdevel&m=154444637519020&w=2 Changes since v1: - introduce four more hints for in-kernel use, as recommended by Dave chinner & Jens axboe. This isolates kernel-mode hints from user-mode ones. - remove mount-option to specify write-hint, as recommended by Jan kara & Dave chinner. Rather, FS always sets write-hint for journal. This gets ignored if device does not support stream. - Removed code-redundancy for write_dirty_buffer (Jan kara's review comment) Kanchan Joshi (4): block: Increase count of supported write-hints fs: introduce four macros for in-kernel hints fs: introduce APIs to enable sending write-hint with buffer-head fs/ext4,jbd2: add support for passing write-hint with journal. fs/buffer.c | 18 ++++++++++++++++-- fs/ext4/super.c | 2 ++ fs/jbd2/commit.c | 11 +++++++---- fs/jbd2/journal.c | 3 ++- fs/jbd2/revoke.c | 3 ++- include/linux/blkdev.h | 5 ++++- include/linux/buffer_head.h | 3 +++ include/linux/fs.h | 5 +++++ include/linux/jbd2.h | 8 ++++++++ 9 files changed, 49 insertions(+), 9 deletions(-) -- 2.7.4