[PATCH 1/1] DmaBufAllocator: Make DmaSyncer non-copyable

[Kieran Bingham]

Quoting Harvey Yang (2024-11-29 18:53:28)
> This fixes commit 39482d59fe7160740ea5dd61f3ed965a88d848ce.

Have you seen how we style fixes tags to match the linux kernel?

Taken from: https://docs.kernel.org/process/submitting-patches.html#describe-your-changes


"""

If your patch fixes a bug in a specific commit, e.g. you found an issue
using git bisect, please use the ‘Fixes:’ tag with the first 12
characters of the SHA-1 ID, and the one line summary. Do not split the
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Fixes: 54a4f0239f2e ("KVM: MMU: make kvm_mmu_zap_page() return the number of pages it actually freed")

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"""



> 
> As DmaSyncer does sync start/end in the c'tor/d'tor, copying a DmaSyncer
> instance would trigger sync end earlier than expected. This patch makes
> it non-copyable to avoid the issue.
> 
> Signed-off-by: Harvey Yang <chenghaoyang at chromium.org>

With the fixes tag corrected


Reviewed-by: Kieran Bingham <kieran.bingham at ideasonboard.com>

> ---
>  include/libcamera/internal/dma_buf_allocator.h |  5 +++++
>  src/libcamera/dma_buf_allocator.cpp            | 10 ++++++++++
>  2 files changed, 15 insertions(+)
> 
> diff --git a/include/libcamera/internal/dma_buf_allocator.h b/include/libcamera/internal/dma_buf_allocator.h
> index fc5de2c13..0cb209630 100644
> --- a/include/libcamera/internal/dma_buf_allocator.h
> +++ b/include/libcamera/internal/dma_buf_allocator.h
> @@ -60,9 +60,14 @@ public:
>  
>         explicit DmaSyncer(SharedFD fd, SyncType type = SyncType::ReadWrite);
>  
> +       DmaSyncer(DmaSyncer &&) = default;
> +       DmaSyncer &operator=(DmaSyncer &&) = default;
> +
>         ~DmaSyncer();
>  
>  private:
> +       LIBCAMERA_DISABLE_COPY(DmaSyncer)
> +
>         void sync(uint64_t step);
>  
>         SharedFD fd_;
> diff --git a/src/libcamera/dma_buf_allocator.cpp b/src/libcamera/dma_buf_allocator.cpp
> index 3cc52f968..5f517828d 100644
> --- a/src/libcamera/dma_buf_allocator.cpp
> +++ b/src/libcamera/dma_buf_allocator.cpp
> @@ -311,6 +311,16 @@ DmaSyncer::DmaSyncer(SharedFD fd, SyncType type)
>         sync(DMA_BUF_SYNC_START);
>  }
>  
> +/**
> + * \fn DmaSyncer::DmaSyncer(DmaSyncer &&) = default;
> + * \brief Enable move on class DmaSyncer
> + */
> +
> +/**
> + * \fn DmaSyncer::operator=(DmaSyncer &&) = default;
> + * \brief Enable move on class DmaSyncer
> + */
> +
>  DmaSyncer::~DmaSyncer()
>  {
>         sync(DMA_BUF_SYNC_END);
> -- 
> 2.47.0.338.g60cca15819-goog
>