Re: [Qemu-devel] [PATCH RFC 1/8] exec: Fix Xen RAM allocation with unusual options

[Stefano Stabellini]

On Thu, 13 Jun 2013, Markus Armbruster wrote:
> Issues:
> 
> * We try to obey -mem-path even though it can't work with Xen.
> 
> * To implement -machine mem-merge, we call
>   memory_try_enable_merging(new_block->host, size).  But with Xen,
>   new_block->host remains null.  Oops.
> 
> Fix by separating Xen allocation from normal allocation.
> 
> Signed-off-by: Markus Armbruster <address@hidden>

Acked-by: Stefano Stabellini <address@hidden>


>  exec.c | 20 ++++++++++++--------
>  1 file changed, 12 insertions(+), 8 deletions(-)
> 
> diff --git a/exec.c b/exec.c
> index 5b8b40d..b424e12 100644
> --- a/exec.c
> +++ b/exec.c
> @@ -1081,6 +1081,12 @@ ram_addr_t qemu_ram_alloc_from_ptr(ram_addr_t size, 
> void *host,
>      if (host) {
>          new_block->host = host;
>          new_block->flags |= RAM_PREALLOC_MASK;
> +    } else if (xen_enabled()) {
> +        if (mem_path) {
> +            fprintf(stderr, "-mem-path not supported with Xen\n");
> +            exit(1);
> +        }
> +        xen_ram_alloc(new_block->offset, size, mr);
>      } else {
>          if (mem_path) {
>  #if defined (__linux__) && !defined(TARGET_S390X)
> @@ -1094,9 +1100,7 @@ ram_addr_t qemu_ram_alloc_from_ptr(ram_addr_t size, 
> void *host,
>              exit(1);
>  #endif
>          } else {
> -            if (xen_enabled()) {
> -                xen_ram_alloc(new_block->offset, size, mr);
> -            } else if (kvm_enabled()) {
> +            if (kvm_enabled()) {
>                  /* some s390/kvm configurations have special constraints */
>                  new_block->host = kvm_ram_alloc(size);
>              } else {
> @@ -1174,6 +1178,8 @@ void qemu_ram_free(ram_addr_t addr)
>              ram_list.version++;
>              if (block->flags & RAM_PREALLOC_MASK) {
>                  ;
> +            } else if (xen_enabled()) {
> +                xen_invalidate_map_cache_entry(block->host);
>              } else if (mem_path) {
>  #if defined (__linux__) && !defined(TARGET_S390X)
>                  if (block->fd) {
> @@ -1186,11 +1192,7 @@ void qemu_ram_free(ram_addr_t addr)
>                  abort();
>  #endif
>              } else {
> -                if (xen_enabled()) {
> -                    xen_invalidate_map_cache_entry(block->host);
> -                } else {
> -                    qemu_anon_ram_free(block->host, block->length);
> -                }
> +                qemu_anon_ram_free(block->host, block->length);
>              }
>              g_free(block);
>              break;
> @@ -1214,6 +1216,8 @@ void qemu_ram_remap(ram_addr_t addr, ram_addr_t length)
>              vaddr = block->host + offset;
>              if (block->flags & RAM_PREALLOC_MASK) {
>                  ;
> +            } else if (xen_enabled()) {
> +                abort();
>              } else {
>                  flags = MAP_FIXED;
>                  munmap(vaddr, length);
> -- 
> 1.7.11.7
>