Re: [PATCH v3 4/4] hw/block/nvme: Align I/O BAR to 4 KiB

[Dmitry Fomichev]

On Tue, 2020-06-30 at 13:04 +0200, Philippe Mathieu-Daudé wrote:
> Simplify the NVMe emulated device by aligning the I/O BAR to 4 KiB.
> 
> Reviewed-by: Klaus Jensen <k.jensen@samsung.com>
> Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
> ---
>  include/block/nvme.h | 2 ++
>  hw/block/nvme.c      | 5 ++---
>  2 files changed, 4 insertions(+), 3 deletions(-)
> 
> diff --git a/include/block/nvme.h b/include/block/nvme.h
> index 82c384614a..4e1cea576a 100644
> --- a/include/block/nvme.h
> +++ b/include/block/nvme.h
> @@ -22,6 +22,7 @@ typedef struct QEMU_PACKED NvmeBar {
>      uint32_t    pmrebs;
>      uint32_t    pmrswtp;
>      uint64_t    pmrmsc;
> +    uint8_t     reserved[484];
>  } NvmeBar;
>  
>  enum NvmeCapShift {
> @@ -879,6 +880,7 @@ enum NvmeIdNsDps {
>  
>  static inline void _nvme_check_size(void)
>  {
> +    QEMU_BUILD_BUG_ON(sizeof(NvmeBar) != 4096);
>      QEMU_BUILD_BUG_ON(sizeof(NvmeAerResult) != 4);
>      QEMU_BUILD_BUG_ON(sizeof(NvmeCqe) != 16);
>      QEMU_BUILD_BUG_ON(sizeof(NvmeDsmRange) != 16);
> diff --git a/hw/block/nvme.c b/hw/block/nvme.c
> index 6628d0a4ba..2aa54bc20e 100644
> --- a/hw/block/nvme.c
> +++ b/hw/block/nvme.c
> @@ -55,7 +55,6 @@
>  #include "nvme.h"
>  
>  #define NVME_MAX_IOQPAIRS 0xffff
> -#define NVME_REG_SIZE 0x1000
>  #define NVME_DB_SIZE  4
>  #define NVME_CMB_BIR 2
>  #define NVME_PMR_BIR 2
> @@ -1322,7 +1321,7 @@ static void nvme_mmio_write(void *opaque, hwaddr addr, 
> uint64_t data,
>      NvmeCtrl *n = (NvmeCtrl *)opaque;
>      if (addr < sizeof(n->bar)) {
>          nvme_write_bar(n, addr, data, size);
> -    } else if (addr >= 0x1000) {
> +    } else {
>          nvme_process_db(n, addr, data);
>      }
>  }
> @@ -1416,7 +1415,7 @@ static void nvme_init_state(NvmeCtrl *n)
>  {
>      n->num_namespaces = 1;
>      /* add one to max_ioqpairs to account for the admin queue pair */
> -    n->reg_size = pow2ceil(NVME_REG_SIZE +
> +    n->reg_size = pow2ceil(sizeof(NvmeBar) +
>                             2 * (n->params.max_ioqpairs + 1) * NVME_DB_SIZE);
>      n->namespaces = g_new0(NvmeNamespace, n->num_namespaces);
>      n->sq = g_new0(NvmeSQueue *, n->params.max_ioqpairs + 1);
> -- 
> 2.21.3
> 
> 

Reviewed-by: Dmitry Fomichev <dmitry.fomichev@wdc.com>