Re: [Qemu-devel] [PATCH v2 09/11] memory: return MemoryRegion from qemu_ram_addr_from_host

[Jan Kiszka <jan.kiszka@siemens.com>]

On 2013-06-28 18:58, Paolo Bonzini wrote:
> It will be needed in the next patches.
> 
> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
> ---
>  cputlb.c                  |  2 +-
>  exec.c                    | 33 ++++++++++++++++++++-------------
>  include/exec/cpu-common.h |  2 +-
>  target-i386/kvm.c         |  4 ++--
>  4 files changed, 24 insertions(+), 17 deletions(-)
> 
> diff --git a/cputlb.c b/cputlb.c
> index b716bbe..51381ae 100644
> --- a/cputlb.c
> +++ b/cputlb.c
> @@ -162,7 +162,7 @@ static inline ram_addr_t qemu_ram_addr_from_host_nofail(void *ptr)
>  {
>      ram_addr_t ram_addr;
>  
> -    if (qemu_ram_addr_from_host(ptr, &ram_addr)) {
> +    if (qemu_ram_addr_from_host(ptr, &ram_addr) == NULL) {
>          fprintf(stderr, "Bad ram pointer %p\n", ptr);
>          abort();
>      }
> diff --git a/exec.c b/exec.c
> index aa76366..a372963 100644
> --- a/exec.c
> +++ b/exec.c
> @@ -1296,15 +1296,7 @@ void qemu_ram_remap(ram_addr_t addr, ram_addr_t length)
>  }
>  #endif /* !_WIN32 */
>  
> -/* Return a host pointer to ram allocated with qemu_ram_alloc.
> -   With the exception of the softmmu code in this file, this should
> -   only be used for local memory (e.g. video ram) that the device owns,
> -   and knows it isn't going to access beyond the end of the block.
> -
> -   It should not be used for general purpose DMA.
> -   Use cpu_physical_memory_map/cpu_physical_memory_rw instead.
> - */
> -void *qemu_get_ram_ptr(ram_addr_t addr)
> +static RAMBlock *qemu_get_ram_block(ram_addr_t addr)
>  {
>      RAMBlock *block;
>  
> @@ -1324,6 +1316,21 @@ void *qemu_get_ram_ptr(ram_addr_t addr)
>  
>  found:
>      ram_list.mru_block = block;
> +    return block;
> +}
> +
> +/* Return a host pointer to ram allocated with qemu_ram_alloc.
> +   With the exception of the softmmu code in this file, this should
> +   only be used for local memory (e.g. video ram) that the device owns,
> +   and knows it isn't going to access beyond the end of the block.
> +
> +   It should not be used for general purpose DMA.
> +   Use cpu_physical_memory_map/cpu_physical_memory_rw instead.
> + */
> +void *qemu_get_ram_ptr(ram_addr_t addr)
> +{
> +    RAMBlock *block = qemu_get_ram_block(addr);
> +
>      if (xen_enabled()) {
>          /* We need to check if the requested address is in the RAM
>           * because we don't want to map the entire memory in QEMU.
> @@ -1400,14 +1407,14 @@ static void *qemu_ram_ptr_length(ram_addr_t addr, ram_addr_t *size)
>  
>  /* Some of the softmmu routines need to translate from a host pointer
>     (typically a TLB entry) back to a ram offset.  */
> -int qemu_ram_addr_from_host(void *ptr, ram_addr_t *ram_addr)
> +MemoryRegion *qemu_ram_addr_from_host(void *ptr, ram_addr_t *ram_addr)
>  {
>      RAMBlock *block;
>      uint8_t *host = ptr;
>  
>      if (xen_enabled()) {
>          *ram_addr = xen_ram_addr_from_mapcache(ptr);
> -        return 0;
> +        return qemu_get_ram_block(*ram_addr)->mr;
>      }
>  
>      block = ram_list.mru_block;
> @@ -1425,11 +1432,11 @@ int qemu_ram_addr_from_host(void *ptr, ram_addr_t *ram_addr)
>          }
>      }
>  
> -    return -1;
> +    return NULL;
>  
>  found:
>      *ram_addr = block->offset + (host - block->host);
> -    return 0;
> +    return block->mr;
>  }
>  
>  static void notdirty_mem_write(void *opaque, hwaddr ram_addr,
> diff --git a/include/exec/cpu-common.h b/include/exec/cpu-common.h
> index 8063ba2..8f75233 100644
> --- a/include/exec/cpu-common.h
> +++ b/include/exec/cpu-common.h
> @@ -50,7 +50,7 @@ typedef uint32_t CPUReadMemoryFunc(void *opaque, hwaddr addr);
>  
>  void qemu_ram_remap(ram_addr_t addr, ram_addr_t length);
>  /* This should not be used by devices.  */
> -int qemu_ram_addr_from_host(void *ptr, ram_addr_t *ram_addr);
> +MemoryRegion *qemu_ram_addr_from_host(void *ptr, ram_addr_t *ram_addr);
>  void qemu_ram_set_idstr(ram_addr_t addr, const char *name, DeviceState *dev);
>  
>  void cpu_physical_memory_rw(hwaddr addr, uint8_t *buf,
> diff --git a/target-i386/kvm.c b/target-i386/kvm.c
> index 9ffb6ca..7ba98cd 100644
> --- a/target-i386/kvm.c
> +++ b/target-i386/kvm.c
> @@ -318,7 +318,7 @@ int kvm_arch_on_sigbus_vcpu(CPUState *c, int code, void *addr)
>  
>      if ((env->mcg_cap & MCG_SER_P) && addr
>          && (code == BUS_MCEERR_AR || code == BUS_MCEERR_AO)) {
> -        if (qemu_ram_addr_from_host(addr, &ram_addr) ||
> +        if (qemu_ram_addr_from_host(addr, &ram_addr) == NULL ||
>              !kvm_physical_memory_addr_from_host(c->kvm_state, addr, &paddr)) {
>              fprintf(stderr, "Hardware memory error for memory used by "
>                      "QEMU itself instead of guest system!\n");
> @@ -350,7 +350,7 @@ int kvm_arch_on_sigbus(int code, void *addr)
>          hwaddr paddr;
>  
>          /* Hope we are lucky for AO MCE */
> -        if (qemu_ram_addr_from_host(addr, &ram_addr) ||
> +        if (qemu_ram_addr_from_host(addr, &ram_addr) == NULL ||
>              !kvm_physical_memory_addr_from_host(CPU(first_cpu)->kvm_state,
>                                                  addr, &paddr)) {
>              fprintf(stderr, "Hardware memory error for memory used by "
> 

Reviewed-by: Jan Kiszka <jan.kiszka@siemens.com>

Jan

-- 
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