x86/hyper-v: Make hv_do_hypercall() inline
We have only three call sites for hv_do_hypercall() and we're going to
change HVCALL_SIGNAL_EVENT to doing fast hypercall so we can inline this
function for optimization.
Hyper-V top level functional specification states that r9-r11 registers
and flags may be clobbered by the hypervisor during hypercall and with
inlining this is somewhat important, add the clobbers.
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/20170802160921.21791-3-vkuznets@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
diff --git a/arch/x86/hyperv/hv_init.c b/arch/x86/hyperv/hv_init.c
index 5b882cc..691603e 100644
--- a/arch/x86/hyperv/hv_init.c
+++ b/arch/x86/hyperv/hv_init.c
@@ -75,7 +75,8 @@ static struct clocksource hyperv_cs_msr = {
.flags = CLOCK_SOURCE_IS_CONTINUOUS,
};
-static void *hypercall_pg;
+void *hv_hypercall_pg;
+EXPORT_SYMBOL_GPL(hv_hypercall_pg);
struct clocksource *hyperv_cs;
EXPORT_SYMBOL_GPL(hyperv_cs);
@@ -102,15 +103,15 @@ void hyperv_init(void)
guest_id = generate_guest_id(0, LINUX_VERSION_CODE, 0);
wrmsrl(HV_X64_MSR_GUEST_OS_ID, guest_id);
- hypercall_pg = __vmalloc(PAGE_SIZE, GFP_KERNEL, PAGE_KERNEL_RX);
- if (hypercall_pg == NULL) {
+ hv_hypercall_pg = __vmalloc(PAGE_SIZE, GFP_KERNEL, PAGE_KERNEL_RX);
+ if (hv_hypercall_pg == NULL) {
wrmsrl(HV_X64_MSR_GUEST_OS_ID, 0);
return;
}
rdmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64);
hypercall_msr.enable = 1;
- hypercall_msr.guest_physical_address = vmalloc_to_pfn(hypercall_pg);
+ hypercall_msr.guest_physical_address = vmalloc_to_pfn(hv_hypercall_pg);
wrmsrl(HV_X64_MSR_HYPERCALL, hypercall_msr.as_uint64);
/*
@@ -170,51 +171,6 @@ void hyperv_cleanup(void)
}
EXPORT_SYMBOL_GPL(hyperv_cleanup);
-/*
- * hv_do_hypercall- Invoke the specified hypercall
- */
-u64 hv_do_hypercall(u64 control, void *input, void *output)
-{
- u64 input_address = (input) ? virt_to_phys(input) : 0;
- u64 output_address = (output) ? virt_to_phys(output) : 0;
-#ifdef CONFIG_X86_64
- u64 hv_status = 0;
-
- if (!hypercall_pg)
- return (u64)ULLONG_MAX;
-
- __asm__ __volatile__("mov %0, %%r8" : : "r" (output_address) : "r8");
- __asm__ __volatile__("call *%3" : "=a" (hv_status) :
- "c" (control), "d" (input_address),
- "m" (hypercall_pg));
-
- return hv_status;
-
-#else
-
- u32 control_hi = control >> 32;
- u32 control_lo = control & 0xFFFFFFFF;
- u32 hv_status_hi = 1;
- u32 hv_status_lo = 1;
- u32 input_address_hi = input_address >> 32;
- u32 input_address_lo = input_address & 0xFFFFFFFF;
- u32 output_address_hi = output_address >> 32;
- u32 output_address_lo = output_address & 0xFFFFFFFF;
-
- if (!hypercall_pg)
- return (u64)ULLONG_MAX;
-
- __asm__ __volatile__ ("call *%8" : "=d"(hv_status_hi),
- "=a"(hv_status_lo) : "d" (control_hi),
- "a" (control_lo), "b" (input_address_hi),
- "c" (input_address_lo), "D"(output_address_hi),
- "S"(output_address_lo), "m" (hypercall_pg));
-
- return hv_status_lo | ((u64)hv_status_hi << 32);
-#endif /* !x86_64 */
-}
-EXPORT_SYMBOL_GPL(hv_do_hypercall);
-
void hyperv_report_panic(struct pt_regs *regs)
{
static bool panic_reported;