Re: [Qemu-devel] [PATCH v3 33/40] ivshmem: Inline check_shm_size() into its only caller

[Marc-André Lureau]

Hi

On Tue, Mar 15, 2016 at 7:34 PM, Markus Armbruster <address@hidden> wrote:
> Improve the error messages while there.
>
> Signed-off-by: Markus Armbruster <address@hidden>

I'd prefer we keep a seperate function to handle the shm checks, but I
don't mind much so:

Reviewed-by: Marc-André Lureau <address@hidden>


> ---
>  hw/misc/ivshmem.c | 37 +++++++++++--------------------------
>  1 file changed, 11 insertions(+), 26 deletions(-)
>
> diff --git a/hw/misc/ivshmem.c b/hw/misc/ivshmem.c
> index 1b1de65..e6282ab 100644
> --- a/hw/misc/ivshmem.c
> +++ b/hw/misc/ivshmem.c
> @@ -343,29 +343,6 @@ static void watch_vector_notifier(IVShmemState *s, 
> EventNotifier *n,
>                          NULL, &s->msi_vectors[vector]);
>  }
>
> -static int check_shm_size(IVShmemState *s, int fd, Error **errp)
> -{
> -    /* check that the guest isn't going to try and map more memory than the
> -     * the object has allocated return -1 to indicate error */
> -
> -    struct stat buf;
> -
> -    if (fstat(fd, &buf) < 0) {
> -        error_setg(errp, "exiting: fstat on fd %d failed: %s",
> -                   fd, strerror(errno));
> -        return -1;
> -    }
> -
> -    if (s->ivshmem_size > buf.st_size) {
> -        error_setg(errp, "Requested memory size greater"
> -                   " than shared object size (%zu > %" PRIu64")",
> -                   s->ivshmem_size, (uint64_t)buf.st_size);
> -        return -1;
> -    } else {
> -        return 0;
> -    }
> -}
> -
>  static void ivshmem_add_eventfd(IVShmemState *s, int posn, int i)
>  {
>      memory_region_add_eventfd(&s->ivshmem_mmio,
> @@ -480,7 +457,7 @@ static void setup_interrupt(IVShmemState *s, int vector, 
> Error **errp)
>
>  static void process_msg_shmem(IVShmemState *s, int fd, Error **errp)
>  {
> -    Error *err = NULL;
> +    struct stat buf;
>      void *ptr;
>
>      if (s->ivshmem_bar2) {
> @@ -489,8 +466,16 @@ static void process_msg_shmem(IVShmemState *s, int fd, 
> Error **errp)
>          return;
>      }
>
> -    if (check_shm_size(s, fd, &err) == -1) {
> -        error_propagate(errp, err);
> +    if (fstat(fd, &buf) < 0) {
> +        error_setg_errno(errp, errno,
> +            "can't determine size of shared memory sent by server");
> +        close(fd);
> +        return;
> +    }
> +
> +    if (s->ivshmem_size > buf.st_size) {
> +        error_setg(errp, "server sent only %zd bytes of shared memory",
> +                   (size_t)buf.st_size);
>          close(fd);
>          return;
>      }
> --
> 2.4.3
>
>



-- 
Marc-André Lureau