Commit fc53662f authored by Vitaly Kuznetsov's avatar Vitaly Kuznetsov Committed by Ingo Molnar

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: default avatarVitaly Kuznetsov <vkuznets@redhat.com>
Reviewed-by: default avatarAndy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: default avatarStephen 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.comSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
parent 79cadff2
......@@ -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;
......
......@@ -3,6 +3,7 @@
#include <linux/types.h>
#include <linux/atomic.h>
#include <asm/io.h>
#include <asm/hyperv.h>
/*
......@@ -168,6 +169,45 @@ void hv_remove_crash_handler(void);
#if IS_ENABLED(CONFIG_HYPERV)
extern struct clocksource *hyperv_cs;
extern void *hv_hypercall_pg;
static inline 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;
u64 hv_status;
register void *__sp asm(_ASM_SP);
#ifdef CONFIG_X86_64
if (!hv_hypercall_pg)
return U64_MAX;
__asm__ __volatile__("mov %4, %%r8\n"
"call *%5"
: "=a" (hv_status), "+r" (__sp),
"+c" (control), "+d" (input_address)
: "r" (output_address), "m" (hv_hypercall_pg)
: "cc", "memory", "r8", "r9", "r10", "r11");
#else
u32 input_address_hi = upper_32_bits(input_address);
u32 input_address_lo = lower_32_bits(input_address);
u32 output_address_hi = upper_32_bits(output_address);
u32 output_address_lo = lower_32_bits(output_address);
if (!hv_hypercall_pg)
return U64_MAX;
__asm__ __volatile__("call *%7"
: "=A" (hv_status),
"+c" (input_address_lo), "+r" (__sp)
: "A" (control),
"b" (input_address_hi),
"D"(output_address_hi), "S"(output_address_lo),
"m" (hv_hypercall_pg)
: "cc", "memory");
#endif /* !x86_64 */
return hv_status;
}
void hyperv_init(void);
void hyperv_report_panic(struct pt_regs *regs);
......
......@@ -32,6 +32,8 @@
#include <linux/hyperv.h>
#include <linux/export.h>
#include <asm/hyperv.h>
#include <asm/mshyperv.h>
#include "hyperv_vmbus.h"
......
......@@ -1187,7 +1187,6 @@ int vmbus_allocate_mmio(struct resource **new, struct hv_device *device_obj,
bool fb_overlap_ok);
void vmbus_free_mmio(resource_size_t start, resource_size_t size);
int vmbus_cpu_number_to_vp_number(int cpu_number);
u64 hv_do_hypercall(u64 control, void *input, void *output);
/*
* GUID definitions of various offer types - services offered to the guest.
......
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