Re: [PATCH 0/2] Support direct I/O read and write for memory allocated by dmabuf

[Christian König]

Am 10.07.24 um 15:57 schrieb Lei Liu:
> Use vm_insert_page to establish a mapping for the memory allocated
> by dmabuf, thus supporting direct I/O read and write; and fix the
> issue of incorrect memory statistics after mapping dmabuf memory.

Well big NAK to that! Direct I/O is intentionally disabled on DMA-bufs.

We already discussed enforcing that in the DMA-buf framework and this 
patch probably means that we should really do that.

Regards,
Christian.

> Lei Liu (2):
>    mm: dmabuf_direct_io: Support direct_io for memory allocated by dmabuf
>    mm: dmabuf_direct_io: Fix memory statistics error for dmabuf allocated
>      memory with direct_io support
>
>   drivers/dma-buf/heaps/system_heap.c |  5 +++--
>   fs/proc/task_mmu.c                  |  8 +++++++-
>   include/linux/mm.h                  |  1 +
>   mm/memory.c                         | 15 ++++++++++-----
>   mm/rmap.c                           |  9 +++++----
>   5 files changed, 26 insertions(+), 12 deletions(-)