Re: [PATCH 0/2] Introduce IORING_OP_MMAP

["David Hildenbrand (arm)" <david@kernel.org>]

On 1/29/26 23:11, Gabriel Krisman Bertazi wrote:
> Hi,
> 
> There's been a few requests over time for supporting mmap(2) over
> io_uring. The reasoning are twofold: 1) serving as base for batching
> multiple mappings in a single operation 2) supporting mmap of fixed
> files.
> 
> Since mmap can operate on either anonymous memory and file descriptors,
> patch 1 adds support for optional fds in io_uring commands.  Patch 2
> implements the mmap operation itself.
> 
> Note this patchset doesn't do any kind of smarter batching in MM.  While
> we can potentially do some interesting optimizations already, like
> holding the MM write lock instead of reacquiring it for each mapping, I
> wanted to focus on the API discussion first.  This is left as future
> work.
> 
> liburing support, including testcases, will be sent shortly to the list,
> but can also be found at:

Just a general question: why do we unlock each syscall individually, and 
not in some intelligent way, all syscalls at once? :)

I assume supporting arbitrary syscalls could be rather hard (or am I 
wrong? :) ).

I also assume that we might want to block some syscalls (do we?), which 
could be done in some generic way (allow-list, deny-list etc).

Again, just curious.

-- 
Cheers

David