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| author | Vitaly Kuznetsov <vkuznets@redhat.com> | 2017-08-02 19:09:15 +0300 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2017-08-10 17:50:22 +0300 |
| commit | 6a8edbd0c54ae266b12f4f63e406313481c9d4bc (patch) | |
| tree | cf8411957fdf7910e0fcb7d2abfa05d2c7717614 /arch | |
| parent | fc53662f13b889a5a1c069e79ee1e3d4534df132 (diff) | |
| download | linux-6a8edbd0c54ae266b12f4f63e406313481c9d4bc.tar.xz | |
x86/hyper-v: Introduce fast hypercall implementation
Hyper-V supports 'fast' hypercalls when all parameters are passed through
registers. Implement an inline version of a simpliest of these calls:
hypercall with one 8-byte input and no output.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Stephen Hemminger <sthemmin@microsoft.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Jork Loeser <Jork.Loeser@microsoft.com>
Cc: K. Y. Srinivasan <kys@microsoft.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Simon Xiao <sixiao@microsoft.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: devel@linuxdriverproject.org
Link: http://lkml.kernel.org/r/20170802160921.21791-4-vkuznets@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/x86/include/asm/mshyperv.h | 34 |
1 files changed, 34 insertions, 0 deletions
diff --git a/arch/x86/include/asm/mshyperv.h b/arch/x86/include/asm/mshyperv.h index 6fa5e342cc86..e484255bd9de 100644 --- a/arch/x86/include/asm/mshyperv.h +++ b/arch/x86/include/asm/mshyperv.h @@ -209,6 +209,40 @@ static inline u64 hv_do_hypercall(u64 control, void *input, void *output) return hv_status; } +#define HV_HYPERCALL_FAST_BIT BIT(16) + +/* Fast hypercall with 8 bytes of input and no output */ +static inline u64 hv_do_fast_hypercall8(u16 code, u64 input1) +{ + u64 hv_status, control = (u64)code | HV_HYPERCALL_FAST_BIT; + register void *__sp asm(_ASM_SP); + +#ifdef CONFIG_X86_64 + { + __asm__ __volatile__("call *%4" + : "=a" (hv_status), "+r" (__sp), + "+c" (control), "+d" (input1) + : "m" (hv_hypercall_pg) + : "cc", "r8", "r9", "r10", "r11"); + } +#else + { + u32 input1_hi = upper_32_bits(input1); + u32 input1_lo = lower_32_bits(input1); + + __asm__ __volatile__ ("call *%5" + : "=A"(hv_status), + "+c"(input1_lo), + "+r"(__sp) + : "A" (control), + "b" (input1_hi), + "m" (hv_hypercall_pg) + : "cc", "edi", "esi"); + } +#endif + return hv_status; +} + void hyperv_init(void); void hyperv_report_panic(struct pt_regs *regs); bool hv_is_hypercall_page_setup(void); |