Here's v4 of the io_uring interface. No user visible changes this time, outside of bumping the io_uring_sqe submission entry to a full 64-bytes. This aligns better with caches, and leaves us some room to grow for future features. See the v3 posting for full details on the API: https://lore.kernel.org/linux-block/20190112213011.1439-1-axboe@xxxxxxxxx/ What I neglected to mention in the v3 posting, is that the fixed buffer and fixed file interfaces are available through the io_uring_register() system call. This means they can be registered (and unregistered) independently of the io_uring context setup. Patches are against 5.0-rc2 and can also be found in my 'io_uring' git branch: git://git.kernel.dk/linux-block io_uring Changes since v3: - Clean up fixed buffer index validation - Add IORING_OP_NOP for ring perf testing - Drop struct io_kiocb ki_* variable prefix, it clashes with struct kiocb for no reason except to cause confusement - Bump io_uring_sqe to 64 bytes. Cacheline sized and aligned (on x86-64), and more future proof - Use kmalloc_array() - Make the page mlock rlimit incremental and not for root / CAP_IPC_LOCK - Ensure io_uring_register() can't race with fops->release() - Simplify and improve iopoll implementation - Use FOLL_WRITE instead of open-coding it - Fix 32-bit vs 64-bit sizing for the io_uring_register() structs - Added x86 32-bit system calls - Added 32-bit compat mode - Rebased on 5.0-rc2 Documentation/filesystems/vfs.txt | 3 + arch/x86/entry/syscalls/syscall_32.tbl | 3 + arch/x86/entry/syscalls/syscall_64.tbl | 3 + block/bio.c | 59 +- fs/Makefile | 1 + fs/block_dev.c | 19 +- fs/file.c | 15 +- fs/file_table.c | 9 +- fs/gfs2/file.c | 2 + fs/io_uring.c | 2072 ++++++++++++++++++++++++ fs/iomap.c | 48 +- fs/xfs/xfs_file.c | 1 + include/linux/bio.h | 14 + include/linux/blk_types.h | 1 + include/linux/file.h | 2 + include/linux/fs.h | 6 +- include/linux/iomap.h | 1 + include/linux/sched/user.h | 2 +- include/linux/syscalls.h | 7 + include/uapi/linux/io_uring.h | 155 ++ init/Kconfig | 9 + kernel/sys_ni.c | 3 + 22 files changed, 2395 insertions(+), 40 deletions(-) -- Jens Axboe
