From cdacc1278b12d929f9a053c245ff3d16eb7af9f8 Mon Sep 17 00:00:00 2001 From: Jeremy Fitzhardinge Date: Tue, 8 Jul 2008 15:06:46 -0700 Subject: [PATCH] xen64: add 64-bit assembler Split xen-asm into 32- and 64-bit files, and implement the 64-bit variants. Signed-off-by: Jeremy Fitzhardinge Cc: Stephen Tweedie Cc: Eduardo Habkost Cc: Mark McLoughlin Signed-off-by: Ingo Molnar --- arch/x86/xen/Makefile | 2 +- arch/x86/xen/{xen-asm.S => xen-asm_32.S} | 0 arch/x86/xen/xen-asm_64.S | 141 +++++++++++++++++++++++ 3 files changed, 142 insertions(+), 1 deletion(-) rename arch/x86/xen/{xen-asm.S => xen-asm_32.S} (100%) create mode 100644 arch/x86/xen/xen-asm_64.S diff --git a/arch/x86/xen/Makefile b/arch/x86/xen/Makefile index 2ba2d1649131..59c1e539aed2 100644 --- a/arch/x86/xen/Makefile +++ b/arch/x86/xen/Makefile @@ -1,4 +1,4 @@ obj-y := enlighten.o setup.o multicalls.o mmu.o \ - time.o xen-asm.o grant-table.o suspend.o + time.o xen-asm_$(BITS).o grant-table.o suspend.o obj-$(CONFIG_SMP) += smp.o diff --git a/arch/x86/xen/xen-asm.S b/arch/x86/xen/xen-asm_32.S similarity index 100% rename from arch/x86/xen/xen-asm.S rename to arch/x86/xen/xen-asm_32.S diff --git a/arch/x86/xen/xen-asm_64.S b/arch/x86/xen/xen-asm_64.S new file mode 100644 index 000000000000..4ec10827370b --- /dev/null +++ b/arch/x86/xen/xen-asm_64.S @@ -0,0 +1,141 @@ +/* + Asm versions of Xen pv-ops, suitable for either direct use or inlining. + The inline versions are the same as the direct-use versions, with the + pre- and post-amble chopped off. + + This code is encoded for size rather than absolute efficiency, + with a view to being able to inline as much as possible. + + We only bother with direct forms (ie, vcpu in pda) of the operations + here; the indirect forms are better handled in C, since they're + generally too large to inline anyway. + */ + +#include + +#include +#include + +#include + +#define RELOC(x, v) .globl x##_reloc; x##_reloc=v +#define ENDPATCH(x) .globl x##_end; x##_end=. + +/* Pseudo-flag used for virtual NMI, which we don't implement yet */ +#define XEN_EFLAGS_NMI 0x80000000 + +#if 0 +#include + +/* + Enable events. This clears the event mask and tests the pending + event status with one and operation. If there are pending + events, then enter the hypervisor to get them handled. + */ +ENTRY(xen_irq_enable_direct) + /* Unmask events */ + movb $0, PER_CPU_VAR(xen_vcpu_info, XEN_vcpu_info_mask) + + /* Preempt here doesn't matter because that will deal with + any pending interrupts. The pending check may end up being + run on the wrong CPU, but that doesn't hurt. */ + + /* Test for pending */ + testb $0xff, PER_CPU_VAR(xen_vcpu_info, XEN_vcpu_info_pending) + jz 1f + +2: call check_events +1: +ENDPATCH(xen_irq_enable_direct) + ret + ENDPROC(xen_irq_enable_direct) + RELOC(xen_irq_enable_direct, 2b+1) + +/* + Disabling events is simply a matter of making the event mask + non-zero. + */ +ENTRY(xen_irq_disable_direct) + movb $1, PER_CPU_VAR(xen_vcpu_info, XEN_vcpu_info_mask) +ENDPATCH(xen_irq_disable_direct) + ret + ENDPROC(xen_irq_disable_direct) + RELOC(xen_irq_disable_direct, 0) + +/* + (xen_)save_fl is used to get the current interrupt enable status. + Callers expect the status to be in X86_EFLAGS_IF, and other bits + may be set in the return value. We take advantage of this by + making sure that X86_EFLAGS_IF has the right value (and other bits + in that byte are 0), but other bits in the return value are + undefined. We need to toggle the state of the bit, because + Xen and x86 use opposite senses (mask vs enable). + */ +ENTRY(xen_save_fl_direct) + testb $0xff, PER_CPU_VAR(xen_vcpu_info, XEN_vcpu_info_mask) + setz %ah + addb %ah,%ah +ENDPATCH(xen_save_fl_direct) + ret + ENDPROC(xen_save_fl_direct) + RELOC(xen_save_fl_direct, 0) + +/* + In principle the caller should be passing us a value return + from xen_save_fl_direct, but for robustness sake we test only + the X86_EFLAGS_IF flag rather than the whole byte. After + setting the interrupt mask state, it checks for unmasked + pending events and enters the hypervisor to get them delivered + if so. + */ +ENTRY(xen_restore_fl_direct) + testb $X86_EFLAGS_IF>>8, %ah + setz PER_CPU_VAR(xen_vcpu_info, XEN_vcpu_info_mask) + /* Preempt here doesn't matter because that will deal with + any pending interrupts. The pending check may end up being + run on the wrong CPU, but that doesn't hurt. */ + + /* check for unmasked and pending */ + cmpw $0x0001, PER_CPU_VAR(xen_vcpu_info, XEN_vcpu_info_pending) + jz 1f +2: call check_events +1: +ENDPATCH(xen_restore_fl_direct) + ret + ENDPROC(xen_restore_fl_direct) + RELOC(xen_restore_fl_direct, 2b+1) + + +/* + Force an event check by making a hypercall, + but preserve regs before making the call. + */ +check_events: + push %rax + push %rcx + push %rdx + push %rsi + push %rdi + push %r8 + push %r9 + push %r10 + push %r11 + call force_evtchn_callback + pop %r11 + pop %r10 + pop %r9 + pop %r8 + pop %rdi + pop %rsi + pop %rdx + pop %rcx + pop %rax + ret +#endif + +ENTRY(xen_iret) + pushq $0 + jmp hypercall_page + __HYPERVISOR_iret * 32 + +ENTRY(xen_sysexit) + ud2a -- 2.39.2