From fc53662f13b889a5a1c069e79ee1e3d4534df132 Mon Sep 17 00:00:00 2001 From: Vitaly Kuznetsov Date: Wed, 2 Aug 2017 18:09:14 +0200 Subject: [PATCH] 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 Reviewed-by: Andy Shevchenko Reviewed-by: Stephen Hemminger Cc: Andy Lutomirski Cc: Haiyang Zhang Cc: Jork Loeser Cc: K. Y. Srinivasan Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Simon Xiao Cc: Steven Rostedt Cc: Thomas Gleixner Cc: devel@linuxdriverproject.org Link: http://lkml.kernel.org/r/20170802160921.21791-3-vkuznets@redhat.com Signed-off-by: Ingo Molnar --- arch/x86/hyperv/hv_init.c | 54 ++++------------------------------------- arch/x86/include/asm/mshyperv.h | 40 ++++++++++++++++++++++++++++++ drivers/hv/connection.c | 2 ++ include/linux/hyperv.h | 1 - 4 files changed, 47 insertions(+), 50 deletions(-) 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; diff --git a/arch/x86/include/asm/mshyperv.h b/arch/x86/include/asm/mshyperv.h index baea267..6fa5e34 100644 --- a/arch/x86/include/asm/mshyperv.h +++ b/arch/x86/include/asm/mshyperv.h @@ -3,6 +3,7 @@ #include #include +#include #include /* @@ -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); diff --git a/drivers/hv/connection.c b/drivers/hv/connection.c index 59c11ff..45e806e 100644 --- a/drivers/hv/connection.c +++ b/drivers/hv/connection.c @@ -32,6 +32,8 @@ #include #include #include +#include + #include "hyperv_vmbus.h" diff --git a/include/linux/hyperv.h b/include/linux/hyperv.h index b7d7bbe..6608a71 100644 --- a/include/linux/hyperv.h +++ b/include/linux/hyperv.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. -- 2.7.4