Re: [Qemu-devel] [PATCH v7 02/26] exec: add ram_debug_ops support

[Paolo Bonzini]

On 07/02/2018 17:06, Brijesh Singh wrote:
> @@ -3148,7 +3152,11 @@ MemTxResult flatview_read_continue(FlatView *fv, 
> hwaddr addr,
>          } else {
>              /* RAM case */
>              ptr = qemu_ram_ptr_length(mr->ram_block, addr1, &l, false);
> -            memcpy(buf, ptr, l);
> +            if (attrs.debug && mr->ram_debug_ops) {
> +                mr->ram_debug_ops->read(buf, ptr, l, attrs);
> +            } else {
> +                memcpy(buf, ptr, l);
> +            }
>          }
>  
>          if (release_lock) {

You also need to tweak flatview_read in include/exec/memory.h (probably
by adding an "&& !attrs.debug", which leaves the mr->ram_debug_ops->read
to the slow path in exec.c).

> @@ -3218,11 +3226,13 @@ void cpu_physical_memory_rw(hwaddr addr, uint8_t *buf,
>  
>  enum write_rom_type {
>      WRITE_DATA,
> +    READ_DATA,
>      FLUSH_CACHE,
>  };
>  
> -static inline void cpu_physical_memory_write_rom_internal(AddressSpace *as,
> -    hwaddr addr, const uint8_t *buf, int len, enum write_rom_type type)
> +static inline void cpu_physical_memory_rw_internal(AddressSpace *as,
> +    hwaddr addr, uint8_t *buf, int len, MemTxAttrs attrs,
> +    enum write_rom_type type)
>  {
>      hwaddr l;
>      uint8_t *ptr;

I wonder if READ_DATA and WRITE_DATA still need to go down to
cpu_physical_memory_rw_internal.  Maybe you can just call
address_space_rw with &address_space_memory as the address space, and
"(MemTxAttrs) { .debug = 1 }" as the attributes.

Paolo

> @@ -3237,12 +3247,33 @@ static inline void 
> cpu_physical_memory_write_rom_internal(AddressSpace *as,
>          if (!(memory_region_is_ram(mr) ||
>                memory_region_is_romd(mr))) {
>              l = memory_access_size(mr, l, addr1);
> +            /* Pass MMIO down to address address_space_rw */
> +            switch (type) {
> +            case READ_DATA:
> +            case WRITE_DATA:
> +                address_space_rw(as, addr1, attrs, buf, l,
> +                                 type == WRITE_DATA);
> +                break;
> +            case FLUSH_CACHE:
> +                break;
> +            }
>          } else {
>              /* ROM/RAM case */
>              ptr = qemu_map_ram_ptr(mr->ram_block, addr1);
>              switch (type) {
> +            case READ_DATA:
> +                if (mr->ram_debug_ops) {
> +                    mr->ram_debug_ops->read(buf, ptr, l, attrs);
> +                } else {
> +                    memcpy(buf, ptr, l);
> +                }
> +                break;
>              case WRITE_DATA:
> -                memcpy(ptr, buf, l);
> +                if (mr->ram_debug_ops) {
> +                    mr->ram_debug_ops->write(ptr, buf, l, attrs);
> +                } else {
> +                    memcpy(ptr, buf, l);
> +                }
>                  invalidate_and_set_dirty(mr, addr1, l);
>                  break;
>              case FLUSH_CACHE: