[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Qemu-devel] [PATCH 2/3] linux-user: Fix NR_fadvise64 and NR_fadvise
From: |
Laurent Vivier |
Subject: |
Re: [Qemu-devel] [PATCH 2/3] linux-user: Fix NR_fadvise64 and NR_fadvise64_64 for 32-bit guests |
Date: |
Thu, 2 Jun 2016 15:29:49 +0200 |
User-agent: |
Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.1.0 |
Le 31/05/2016 à 16:45, Peter Maydell a écrit :
> Fix errors in the implementation of NR_fadvise64 and NR_fadvise64_64
> for 32-bit guests, which pass their off_t values in register pairs.
> We can't use the 64-bit code path for this, so split out the 32-bit
> cases, so that we can correctly handle the "only offset is 64-bit"
> and "both offset and length are 64-bit" syscall flavours, and
> "uses aligned register pairs" and "does not" flavours of target.
>
> Signed-off-by: Peter Maydell <address@hidden>
Reviewed-by: Laurent Vivier <address@hidden>
> ---
> linux-user/syscall.c | 40 ++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 40 insertions(+)
>
> diff --git a/linux-user/syscall.c b/linux-user/syscall.c
> index 4894919..638b455 100644
> --- a/linux-user/syscall.c
> +++ b/linux-user/syscall.c
> @@ -9340,6 +9340,44 @@ abi_long do_syscall(void *cpu_env, int num, abi_long
> arg1,
> ret = -host_to_target_errno(ret);
> break;
> #endif
> +
> +#if TARGET_ABI_BITS == 32
> +
> +#ifdef TARGET_NR_fadvise64_64
> + case TARGET_NR_fadvise64_64:
> + /* 6 args: fd, offset (high, low), len (high, low), advice */
> + if (regpairs_aligned(cpu_env)) {
> + /* offset is in (3,4), len in (5,6) and advice in 7 */
> + arg2 = arg3;
> + arg3 = arg4;
> + arg4 = arg5;
> + arg5 = arg6;
> + arg6 = arg7;
> + }
> + ret = -host_to_target_errno(posix_fadvise(arg1,
> + target_offset64(arg2,
> arg3),
> + target_offset64(arg4,
> arg5),
> + arg6));
> + break;
> +#endif
> +
> +#ifdef TARGET_NR_fadvise64
> + case TARGET_NR_fadvise64:
> + /* 5 args: fd, offset (high, low), len, advice */
> + if (regpairs_aligned(cpu_env)) {
> + /* offset is in (3,4), len in 5 and advice in 6 */
> + arg2 = arg3;
> + arg3 = arg4;
> + arg4 = arg5;
> + arg5 = arg6;
> + }
> + ret = -host_to_target_errno(posix_fadvise(arg1,
> + target_offset64(arg2,
> arg3),
> + arg4, arg5));
> + break;
> +#endif
> +
> +#else /* not a 32-bit ABI */
> #if defined(TARGET_NR_fadvise64_64) || defined(TARGET_NR_fadvise64)
> #ifdef TARGET_NR_fadvise64_64
> case TARGET_NR_fadvise64_64:
> @@ -9359,6 +9397,8 @@ abi_long do_syscall(void *cpu_env, int num, abi_long
> arg1,
> ret = -posix_fadvise(arg1, arg2, arg3, arg4);
> break;
> #endif
> +#endif /* end of 64-bit ABI fadvise handling */
> +
> #ifdef TARGET_NR_madvise
> case TARGET_NR_madvise:
> /* A straight passthrough may not be safe because qemu sometimes
>
[Prev in Thread] |
Current Thread |
[Next in Thread] |
- Re: [Qemu-devel] [PATCH 2/3] linux-user: Fix NR_fadvise64 and NR_fadvise64_64 for 32-bit guests,
Laurent Vivier <=