Re: [PATCH 04/13] dma: Let dma_memory_set() propagate MemTxResult

[Li Qiang]

Philippe Mathieu-Daudé <philmd@redhat.com> 于2020年9月4日周五 下午11:47写道：
>
> address_space_write() returns a MemTxResult type.
> Do not discard it, return it to the caller.
>
> Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>

Reviewed-by: Li Qiang <liq3ea@gmail.com>

> ---
>  include/sysemu/dma.h | 15 ++++++++++++++-
>  dma-helpers.c        |  7 ++++---
>  2 files changed, 18 insertions(+), 4 deletions(-)
>
> diff --git a/include/sysemu/dma.h b/include/sysemu/dma.h
> index 19bc9ad1b69..ad8a3f82f47 100644
> --- a/include/sysemu/dma.h
> +++ b/include/sysemu/dma.h
> @@ -123,7 +123,20 @@ static inline int dma_memory_write(AddressSpace *as, 
> dma_addr_t addr,
>                           DMA_DIRECTION_FROM_DEVICE);
>  }
>
> -int dma_memory_set(AddressSpace *as, dma_addr_t addr, uint8_t c, dma_addr_t 
> len);
> +/**
> + * dma_memory_set: Fill memory with a constant byte from DMA controller.
> + *
> + * Return a MemTxResult indicating whether the operation succeeded
> + * or failed (eg unassigned memory, device rejected the transaction,
> + * IOMMU fault).
> + *
> + * @as: #AddressSpace to be accessed
> + * @addr: address within that address space
> + * @c: constant byte to fill the memory
> + * @len: the number of bytes to fill with the constant byte
> + */
> +MemTxResult dma_memory_set(AddressSpace *as, dma_addr_t addr,
> +                           uint8_t c, dma_addr_t len);
>
>  /**
>   * address_space_map: Map a physical memory region into a DMA controller
> diff --git a/dma-helpers.c b/dma-helpers.c
> index 41ef24a63b6..4a9e37d6d06 100644
> --- a/dma-helpers.c
> +++ b/dma-helpers.c
> @@ -1,7 +1,7 @@
>  /*
>   * DMA helper functions
>   *
> - * Copyright (c) 2009 Red Hat
> + * Copyright (c) 2009,2020 Red Hat
>   *
>   * This work is licensed under the terms of the GNU General Public License
>   * (GNU GPL), version 2 or later.
> @@ -18,14 +18,15 @@
>
>  /* #define DEBUG_IOMMU */
>
> -int dma_memory_set(AddressSpace *as, dma_addr_t addr, uint8_t c, dma_addr_t 
> len)
> +MemTxResult dma_memory_set(AddressSpace *as, dma_addr_t addr,
> +                           uint8_t c, dma_addr_t len)
>  {
>      dma_barrier(as, DMA_DIRECTION_FROM_DEVICE);
>
>  #define FILLBUF_SIZE 512
>      uint8_t fillbuf[FILLBUF_SIZE];
>      int l;
> -    bool error = false;
> +    MemTxResult error = MEMTX_OK;
>
>      memset(fillbuf, c, FILLBUF_SIZE);
>      while (len > 0) {
> --
> 2.26.2
>
>