Chandan Rajendra
2014-Jul-16 14:45 UTC
[RFC PATCH V4 00/12] Btrfs: Subpagesize-blocksize: Get rid of whole page I/O.
This patchset continues with the work posted earlier at https://www.mail-archive.com/linux-btrfs@vger.kernel.org/msg34954.html. Changes from V1: 1. Remove usage of bio_vec->bv_{len,offset} in end_bio_extent_readpage() and end_bio_extent_writepage(). Changes from V2: 1. Get __extent_writepage() to write only the dirty blocks of a page. 2. Fix "page private not zero on page" warning message which is printed when running xfstests. Changes from V3: 1. Get "Hole punching" and "Extent preallocation" to work correctly in subpagesize-blocksize scenario. 2. Get btrfs_page_mkwrite() to reserve space in sectorsized units. Xfstests' generic tests were run on an x86_64 machine with the patches applied. The Btrfs kernel module was compiled without ACL and quotas support and hence tests related to those were not run. On multiple runs of the tests with 4k blocksize, 'umount' process would sometimes get blocked indefinitely causing 'hung task detector' to print the function call trace. For 2k blocksize about 15 xfstests' generic test cases fail (reasons include checksum failures, softlockups and BUG_ON()s). The following is a list of known TODO items which will be implemented in future revisions of this patchset: 1. Remove usage of bvec->{bv_offset, bv_len} from btrfs_csum_one_bio. 2. Remove PAGE_CACHE_SIZE delalloc reservation in btrfs_writepage_fixup_worker(). 3. Create separate slab caches for 'extent buffer head' and 'extent buffer'. 4. Add 'leak list' tracking for 'extent buffer' instances. 5. Rename EXTENT_BUFFER_TREE_REF and EXTENT_BUFFER_IN_TREE to EXTENT_BUFFER_HEAD_TREE_REF and EXTENT_BUFFER_HEAD_IN_TREE respectively. 6. Get Xfstests' generic tests to successfully run on both 4k and 2k blocksizes. Chandan Rajendra (10): Btrfs: subpagesize-blocksize: Get rid of whole page reads. Btrfs: subpagesize-blocksize: Get rid of whole page writes. Btrfs: subpagesize-blocksize: __btrfs_buffered_write: Reserve/release extents aligned to block size. Btrfs: subpagesize-blocksize: Read tree blocks whose size is <PAGE_CACHE_SIZE. Btrfs: subpagesize-blocksize: Write only dirty extent buffers belonging to a page Btrfs: subpagesize-blocksize: Compute and look up csums based on sectorsized blocks. Btrfs: subpagesize-blocksize: __extent_writepage: Write only dirty blocks of a page. Btrfs: subpagesize-blocksize: fallocate: Work with sectorsized units. Btrfs: subpagesize-blocksize: btrfs_page_mkwrite: Reserve space in sectorsized units. Btrfs: subpagesize-blocksize: Search for all ordered extents that could span across a page. Chandra Seetharaman (2): Btrfs: subpagesize-blocksize: Define extent_buffer_head. Btrfs: subpagesize-blocksize: Allow mounting filesystems where sectorsize != PAGE_SIZE fs/btrfs/backref.c | 2 +- fs/btrfs/ctree.c | 2 +- fs/btrfs/ctree.h | 8 +- fs/btrfs/disk-io.c | 117 ++--- fs/btrfs/disk-io.h | 3 + fs/btrfs/extent-tree.c | 6 +- fs/btrfs/extent_io.c | 1111 ++++++++++++++++++++++++++++++------------ fs/btrfs/extent_io.h | 48 +- fs/btrfs/file-item.c | 85 ++-- fs/btrfs/file.c | 67 +-- fs/btrfs/inode.c | 158 +++--- fs/btrfs/volumes.c | 2 +- fs/btrfs/volumes.h | 3 + include/trace/events/btrfs.h | 2 +- 14 files changed, 1097 insertions(+), 517 deletions(-) -- 1.8.3.1 -- 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