Re: [PATCH v5 0/2] io_uring: add support for ftruncate

[Jens Axboe <axboe@kernel.dk>]

On 1/24/24 6:35 AM, Cedric Blancher wrote:
> On Wed, 24 Jan 2024 at 13:52, Jens Axboe <axboe@kernel.dk> wrote:
>>
>> On 1/24/24 1:52 AM, Cedric Blancher wrote:
>>> On Wed, 24 Jan 2024 at 09:33, Tony Solomonik <tony.solomonik@gmail.com> wrote:
>>>>
>>>> This patch adds support for doing truncate through io_uring, eliminating
>>>> the need for applications to roll their own thread pool or offload
>>>> mechanism to be able to do non-blocking truncates.
>>>>
>>>> Tony Solomonik (2):
>>>>   Add ftruncate_file that truncates a struct file
>>>>   io_uring: add support for ftruncate
>>>>
>>>>  fs/internal.h                 |  1 +
>>>>  fs/open.c                     | 53 ++++++++++++++++++-----------------
>>>>  include/uapi/linux/io_uring.h |  1 +
>>>>  io_uring/Makefile             |  2 +-
>>>>  io_uring/opdef.c              | 10 +++++++
>>>>  io_uring/truncate.c           | 48 +++++++++++++++++++++++++++++++
>>>>  io_uring/truncate.h           |  4 +++
>>>>  7 files changed, 93 insertions(+), 26 deletions(-)
>>>>  create mode 100644 io_uring/truncate.c
>>>>  create mode 100644 io_uring/truncate.h
>>>>
>>>>
>>>> base-commit: d3fa86b1a7b4cdc4367acacea16b72e0a200b3d7
>>>
>>> Also fallocate() to punch holes, aka sparse files, must be implemented
>>
>> fallocate has been supported for years.
> 
> Does it support punching holes? Does lseek() with SEEK_HOLE and
> SEEK_DATA work, with more than one hole, and/or hole at the end?

It does anything that fallocate(2) will do.

-- 
Jens Axboe