From: Omar Sandoval <osandov@xxxxxx> This series has three parts: new Btrfs ioctls for reading/writing compressed data, support for sending compressed data via Btrfs send, and btrfs-progs support for sending/receiving compressed data and writing it with the new ioctl. The Btrfs ioctls for reading compressed data from a file without decompressing it and for writing compressed data directly to a file are adapted from my previous attempt to do this as an extension to preadv2/pwritev2 [1]. We weren't able to come up with a generic interface that everyone was happy with, so we're going to do this ourselves in Btrfs. If another user comes along, we can generalize it then. Test cases are here [2] Patches 1 and 2 are VFS changes exporting a couple of helpers for checks needed by reads and writes. Patches 3-7 are preparatory Btrfs changes for compressed reads and writes. Patch 8 adds the compressed read ioctl and patch 9 adds the compressed write ioctl. The main use-case for this interface is Btrfs send/receive. Currently, when sending data from one compressed filesystem to another, the sending side decompresses the data and the receiving side recompresses it before writing it out. This is wasteful and can be avoided if we can just send and write compressed extents. Patches 10-14 add the Btrfs send support. See the previous posting for more details and benchmarks [3]. Patches 10-12 prepare some protocol changes for send stream v2. Patch 13 implements compressed send. Patch 14 enables send stream v2 and compressed send in the send ioctl when requested. These patches are based on Dave Sterba's Btrfs misc-next branch [4], which is in turn currently based on v5.14-rc6. 1: https://lore.kernel.org/linux-fsdevel/cover.1623972518.git.osandov@xxxxxx/ 2: https://github.com/osandov/xfstests/tree/btrfs-encoded-io 3: https://lore.kernel.org/linux-btrfs/cover.1615922753.git.osandov@xxxxxx/ 4: https://github.com/kdave/btrfs-devel/tree/misc-next Omar Sandoval (14): fs: export rw_verify_area() fs: export variant of generic_write_checks without iov_iter btrfs: don't advance offset for compressed bios in btrfs_csum_one_bio() btrfs: add ram_bytes and offset to btrfs_ordered_extent btrfs: support different disk extent size for delalloc btrfs: optionally extend i_size in cow_file_range_inline() btrfs: add definitions + documentation for encoded I/O ioctls btrfs: add BTRFS_IOC_ENCODED_READ btrfs: add BTRFS_IOC_ENCODED_WRITE btrfs: add send stream v2 definitions btrfs: send: write larger chunks when using stream v2 btrfs: send: allocate send buffer with alloc_page() and vmap() for v2 btrfs: send: send compressed extents with encoded writes btrfs: send: enable support for stream v2 and compressed writes fs/btrfs/compression.c | 12 +- fs/btrfs/compression.h | 6 +- fs/btrfs/ctree.h | 17 +- fs/btrfs/delalloc-space.c | 18 +- fs/btrfs/file-item.c | 35 +- fs/btrfs/file.c | 68 ++- fs/btrfs/inode.c | 911 +++++++++++++++++++++++++++++++++---- fs/btrfs/ioctl.c | 213 +++++++++ fs/btrfs/ordered-data.c | 124 ++--- fs/btrfs/ordered-data.h | 25 +- fs/btrfs/relocation.c | 2 +- fs/btrfs/send.c | 307 +++++++++++-- fs/btrfs/send.h | 32 +- fs/internal.h | 5 - fs/read_write.c | 41 +- include/linux/fs.h | 2 + include/uapi/linux/btrfs.h | 149 +++++- 17 files changed, 1690 insertions(+), 277 deletions(-) The btrfs-progs patches were written by Boris Burkov with some updates from me. Patches 1-4 are preparation. Patch 5 implements encoded writes. Patch 6 implements the fallback to decompressing. Patches 7 and 8 implement the other commands. Patch 9 adds the new `btrfs send` options. Patch 10 adds a test case. Boris Burkov (10): btrfs-progs: receive: support v2 send stream larger tlv_len btrfs-progs: receive: dynamically allocate sctx->read_buf btrfs-progs: receive: support v2 send stream DATA tlv format btrfs-progs: receive: add send stream v2 cmds and attrs to send.h btrfs-progs: receive: process encoded_write commands btrfs-progs: receive: encoded_write fallback to explicit decode and write btrfs-progs: receive: process fallocate commands btrfs-progs: receive: process setflags ioctl commands btrfs-progs: send: stream v2 ioctl flags btrfs-progs: receive: add tests for basic encoded_write send/receive Documentation/btrfs-receive.asciidoc | 4 + Documentation/btrfs-send.asciidoc | 16 +- cmds/receive-dump.c | 31 +- cmds/receive.c | 347 +++++++++++++++++- cmds/send.c | 54 ++- common/send-stream.c | 157 ++++++-- common/send-stream.h | 7 + ioctl.h | 149 +++++++- libbtrfsutil/btrfs.h | 17 +- send.h | 19 +- .../049-receive-write-encoded/test.sh | 114 ++++++ 11 files changed, 871 insertions(+), 44 deletions(-) create mode 100755 tests/misc-tests/049-receive-write-encoded/test.sh -- 2.32.0
