Re: [PATCH v1 7/9] memory: introduce RAM_NORESERVE and wire it up in qemu_ram_mmap()

[Peter Xu]

On Tue, Feb 09, 2021 at 02:49:37PM +0100, David Hildenbrand wrote:
> @@ -899,13 +899,17 @@ int kvm_s390_mem_op_pv(S390CPU *cpu, uint64_t offset, 
> void *hostbuf,
>   * to grow. We also have to use MAP parameters that avoid
>   * read-only mapping of guest pages.
>   */
> -static void *legacy_s390_alloc(size_t size, uint64_t *align, bool shared)
> +static void *legacy_s390_alloc(size_t size, uint64_t *align, bool shared,
> +                               bool noreserve)
>  {
>      static void *mem;
>  
>      if (mem) {
>          /* we only support one allocation, which is enough for initial ram */
>          return NULL;
> +    } else if (noreserve) {
> +        error_report("Skipping reservation of swap space is not supported.");
> +        return NULL

Semicolon missing.

>      }
>  
>      mem = mmap((void *) 0x800000000ULL, size,
> diff --git a/util/mmap-alloc.c b/util/mmap-alloc.c
> index b50dc86a3c..bb99843106 100644
> --- a/util/mmap-alloc.c
> +++ b/util/mmap-alloc.c
> @@ -20,6 +20,7 @@
>  #include "qemu/osdep.h"
>  #include "qemu/mmap-alloc.h"
>  #include "qemu/host-utils.h"
> +#include "qemu/error-report.h"
>  
>  #define HUGETLBFS_MAGIC       0x958458f6
>  
> @@ -174,12 +175,18 @@ void *qemu_ram_mmap(int fd,
>                      size_t align,
>                      bool readonly,
>                      bool shared,
> -                    bool is_pmem)
> +                    bool is_pmem,
> +                    bool noreserve)

Maybe at some point we should use flags too here to cover all bools.

Thanks,

-- 
Peter Xu