Re: [PATCH v3 0/5] btrfs: encoded reads via io_uring

Mark Harmstone
2024-10-15T08:50:37Z

On 14/10/24 18:44, Boris Burkov wrote:
> >
> On Mon, Oct 14, 2024 at 06:18:22PM +0100, Mark Harmstone wrote:
>> This is a re-do of my previous patchsets: I wasn't happy with how
>> synchronous the previous version was in many ways, nor quite how badly
>> it butchered the existing ioctl.
>>
>> This adds an io_uring cmd to btrfs to match the behaviour of the
>> existing BTRFS_IOC_ENCODED_READ ioctl, which allows the reading of
>> potentially compressed extents directly from the disk.
>>
>> Pavel mentioned on the previous patches whether we definitely need to
>> keep the inode and the extent locked while doing I/O; I think the answer
>> is probably yes, a) to prevent races with no-COW extents, and b) to
>> prevent the extent from being deallocated from under us. But I think
>> it's possible to resolve this, as a future optimization.
>
> What branch is this based off of? I attempted to apply it to the current
> btrfs for-next and
> "btrfs: change btrfs_encoded_read_regular_fill_pages to take a callback"
> did not apply cleanly.

This is against v6.11, because it's the latest stable version. I'm
guessing it ought to have been against upstream/master...

Mark