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-rw-r--r--arch/x86/include/asm/lguest_hcall.h29
-rw-r--r--arch/x86/lguest/boot.c61
-rw-r--r--arch/x86/lguest/i386_head.S2
3 files changed, 54 insertions, 38 deletions
diff --git a/arch/x86/include/asm/lguest_hcall.h b/arch/x86/include/asm/lguest_hcall.h
index ba0eed8aa1a6..b60f2924c413 100644
--- a/arch/x86/include/asm/lguest_hcall.h
+++ b/arch/x86/include/asm/lguest_hcall.h
@@ -28,22 +28,39 @@
#ifndef __ASSEMBLY__
#include <asm/hw_irq.h>
-#include <asm/kvm_para.h>
/*G:030
* But first, how does our Guest contact the Host to ask for privileged
* operations? There are two ways: the direct way is to make a "hypercall",
* to make requests of the Host Itself.
*
- * We use the KVM hypercall mechanism, though completely different hypercall
- * numbers. Seventeen hypercalls are available: the hypercall number is put in
- * the %eax register, and the arguments (when required) are placed in %ebx,
- * %ecx, %edx and %esi. If a return value makes sense, it's returned in %eax.
+ * Our hypercall mechanism uses the highest unused trap code (traps 32 and
+ * above are used by real hardware interrupts). Seventeen hypercalls are
+ * available: the hypercall number is put in the %eax register, and the
+ * arguments (when required) are placed in %ebx, %ecx, %edx and %esi.
+ * If a return value makes sense, it's returned in %eax.
*
* Grossly invalid calls result in Sudden Death at the hands of the vengeful
* Host, rather than returning failure. This reflects Winston Churchill's
* definition of a gentleman: "someone who is only rude intentionally".
-:*/
+ */
+static inline unsigned long
+hcall(unsigned long call,
+ unsigned long arg1, unsigned long arg2, unsigned long arg3,
+ unsigned long arg4)
+{
+ /* "int" is the Intel instruction to trigger a trap. */
+ asm volatile("int $" __stringify(LGUEST_TRAP_ENTRY)
+ /* The call in %eax (aka "a") might be overwritten */
+ : "=a"(call)
+ /* The arguments are in %eax, %ebx, %ecx, %edx & %esi */
+ : "a"(call), "b"(arg1), "c"(arg2), "d"(arg3), "S"(arg4)
+ /* "memory" means this might write somewhere in memory.
+ * This isn't true for all calls, but it's safe to tell
+ * gcc that it might happen so it doesn't get clever. */
+ : "memory");
+ return call;
+}
/* Can't use our min() macro here: needs to be a constant */
#define LGUEST_IRQS (NR_IRQS < 32 ? NR_IRQS: 32)
diff --git a/arch/x86/lguest/boot.c b/arch/x86/lguest/boot.c
index 7e59dc1d3fc2..2bdf628066bd 100644
--- a/arch/x86/lguest/boot.c
+++ b/arch/x86/lguest/boot.c
@@ -115,7 +115,7 @@ static void async_hcall(unsigned long call, unsigned long arg1,
local_irq_save(flags);
if (lguest_data.hcall_status[next_call] != 0xFF) {
/* Table full, so do normal hcall which will flush table. */
- kvm_hypercall4(call, arg1, arg2, arg3, arg4);
+ hcall(call, arg1, arg2, arg3, arg4);
} else {
lguest_data.hcalls[next_call].arg0 = call;
lguest_data.hcalls[next_call].arg1 = arg1;
@@ -145,46 +145,45 @@ static void async_hcall(unsigned long call, unsigned long arg1,
* So, when we're in lazy mode, we call async_hcall() to store the call for
* future processing:
*/
-static void lazy_hcall1(unsigned long call,
- unsigned long arg1)
+static void lazy_hcall1(unsigned long call, unsigned long arg1)
{
if (paravirt_get_lazy_mode() == PARAVIRT_LAZY_NONE)
- kvm_hypercall1(call, arg1);
+ hcall(call, arg1, 0, 0, 0);
else
async_hcall(call, arg1, 0, 0, 0);
}
/* You can imagine what lazy_hcall2, 3 and 4 look like. :*/
static void lazy_hcall2(unsigned long call,
- unsigned long arg1,
- unsigned long arg2)
+ unsigned long arg1,
+ unsigned long arg2)
{
if (paravirt_get_lazy_mode() == PARAVIRT_LAZY_NONE)
- kvm_hypercall2(call, arg1, arg2);
+ hcall(call, arg1, arg2, 0, 0);
else
async_hcall(call, arg1, arg2, 0, 0);
}
static void lazy_hcall3(unsigned long call,
- unsigned long arg1,
- unsigned long arg2,
- unsigned long arg3)
+ unsigned long arg1,
+ unsigned long arg2,
+ unsigned long arg3)
{
if (paravirt_get_lazy_mode() == PARAVIRT_LAZY_NONE)
- kvm_hypercall3(call, arg1, arg2, arg3);
+ hcall(call, arg1, arg2, arg3, 0);
else
async_hcall(call, arg1, arg2, arg3, 0);
}
#ifdef CONFIG_X86_PAE
static void lazy_hcall4(unsigned long call,
- unsigned long arg1,
- unsigned long arg2,
- unsigned long arg3,
- unsigned long arg4)
+ unsigned long arg1,
+ unsigned long arg2,
+ unsigned long arg3,
+ unsigned long arg4)
{
if (paravirt_get_lazy_mode() == PARAVIRT_LAZY_NONE)
- kvm_hypercall4(call, arg1, arg2, arg3, arg4);
+ hcall(call, arg1, arg2, arg3, arg4);
else
async_hcall(call, arg1, arg2, arg3, arg4);
}
@@ -196,13 +195,13 @@ static void lazy_hcall4(unsigned long call,
:*/
static void lguest_leave_lazy_mmu_mode(void)
{
- kvm_hypercall0(LHCALL_FLUSH_ASYNC);
+ hcall(LHCALL_FLUSH_ASYNC, 0, 0, 0, 0);
paravirt_leave_lazy_mmu();
}
static void lguest_end_context_switch(struct task_struct *next)
{
- kvm_hypercall0(LHCALL_FLUSH_ASYNC);
+ hcall(LHCALL_FLUSH_ASYNC, 0, 0, 0, 0);
paravirt_end_context_switch(next);
}
@@ -286,7 +285,7 @@ static void lguest_write_idt_entry(gate_desc *dt,
/* Keep the local copy up to date. */
native_write_idt_entry(dt, entrynum, g);
/* Tell Host about this new entry. */
- kvm_hypercall3(LHCALL_LOAD_IDT_ENTRY, entrynum, desc[0], desc[1]);
+ hcall(LHCALL_LOAD_IDT_ENTRY, entrynum, desc[0], desc[1], 0);
}
/*
@@ -300,7 +299,7 @@ static void lguest_load_idt(const struct desc_ptr *desc)
struct desc_struct *idt = (void *)desc->address;
for (i = 0; i < (desc->size+1)/8; i++)
- kvm_hypercall3(LHCALL_LOAD_IDT_ENTRY, i, idt[i].a, idt[i].b);
+ hcall(LHCALL_LOAD_IDT_ENTRY, i, idt[i].a, idt[i].b, 0);
}
/*
@@ -321,7 +320,7 @@ static void lguest_load_gdt(const struct desc_ptr *desc)
struct desc_struct *gdt = (void *)desc->address;
for (i = 0; i < (desc->size+1)/8; i++)
- kvm_hypercall3(LHCALL_LOAD_GDT_ENTRY, i, gdt[i].a, gdt[i].b);
+ hcall(LHCALL_LOAD_GDT_ENTRY, i, gdt[i].a, gdt[i].b, 0);
}
/*
@@ -334,8 +333,8 @@ static void lguest_write_gdt_entry(struct desc_struct *dt, int entrynum,
{
native_write_gdt_entry(dt, entrynum, desc, type);
/* Tell Host about this new entry. */
- kvm_hypercall3(LHCALL_LOAD_GDT_ENTRY, entrynum,
- dt[entrynum].a, dt[entrynum].b);
+ hcall(LHCALL_LOAD_GDT_ENTRY, entrynum,
+ dt[entrynum].a, dt[entrynum].b, 0);
}
/*
@@ -931,7 +930,7 @@ static int lguest_clockevent_set_next_event(unsigned long delta,
}
/* Please wake us this far in the future. */
- kvm_hypercall1(LHCALL_SET_CLOCKEVENT, delta);
+ hcall(LHCALL_SET_CLOCKEVENT, delta, 0, 0, 0);
return 0;
}
@@ -942,7 +941,7 @@ static void lguest_clockevent_set_mode(enum clock_event_mode mode,
case CLOCK_EVT_MODE_UNUSED:
case CLOCK_EVT_MODE_SHUTDOWN:
/* A 0 argument shuts the clock down. */
- kvm_hypercall0(LHCALL_SET_CLOCKEVENT);
+ hcall(LHCALL_SET_CLOCKEVENT, 0, 0, 0, 0);
break;
case CLOCK_EVT_MODE_ONESHOT:
/* This is what we expect. */
@@ -1100,7 +1099,7 @@ static void set_lguest_basic_apic_ops(void)
/* STOP! Until an interrupt comes in. */
static void lguest_safe_halt(void)
{
- kvm_hypercall0(LHCALL_HALT);
+ hcall(LHCALL_HALT, 0, 0, 0, 0);
}
/*
@@ -1112,8 +1111,8 @@ static void lguest_safe_halt(void)
*/
static void lguest_power_off(void)
{
- kvm_hypercall2(LHCALL_SHUTDOWN, __pa("Power down"),
- LGUEST_SHUTDOWN_POWEROFF);
+ hcall(LHCALL_SHUTDOWN, __pa("Power down"),
+ LGUEST_SHUTDOWN_POWEROFF, 0, 0);
}
/*
@@ -1123,7 +1122,7 @@ static void lguest_power_off(void)
*/
static int lguest_panic(struct notifier_block *nb, unsigned long l, void *p)
{
- kvm_hypercall2(LHCALL_SHUTDOWN, __pa(p), LGUEST_SHUTDOWN_POWEROFF);
+ hcall(LHCALL_SHUTDOWN, __pa(p), LGUEST_SHUTDOWN_POWEROFF, 0, 0);
/* The hcall won't return, but to keep gcc happy, we're "done". */
return NOTIFY_DONE;
}
@@ -1162,7 +1161,7 @@ static __init int early_put_chars(u32 vtermno, const char *buf, int count)
len = sizeof(scratch) - 1;
scratch[len] = '\0';
memcpy(scratch, buf, len);
- kvm_hypercall1(LHCALL_NOTIFY, __pa(scratch));
+ hcall(LHCALL_NOTIFY, __pa(scratch), 0, 0, 0);
/* This routine returns the number of bytes actually written. */
return len;
@@ -1174,7 +1173,7 @@ static __init int early_put_chars(u32 vtermno, const char *buf, int count)
*/
static void lguest_restart(char *reason)
{
- kvm_hypercall2(LHCALL_SHUTDOWN, __pa(reason), LGUEST_SHUTDOWN_RESTART);
+ hcall(LHCALL_SHUTDOWN, __pa(reason), LGUEST_SHUTDOWN_RESTART, 0, 0);
}
/*G:050
diff --git a/arch/x86/lguest/i386_head.S b/arch/x86/lguest/i386_head.S
index 27eac0faee48..4f420c2f2d55 100644
--- a/arch/x86/lguest/i386_head.S
+++ b/arch/x86/lguest/i386_head.S
@@ -32,7 +32,7 @@ ENTRY(lguest_entry)
*/
movl $LHCALL_LGUEST_INIT, %eax
movl $lguest_data - __PAGE_OFFSET, %ebx
- .byte 0x0f,0x01,0xc1 /* KVM_HYPERCALL */
+ int $LGUEST_TRAP_ENTRY
/* Set up the initial stack so we can run C code. */
movl $(init_thread_union+THREAD_SIZE),%esp
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-05 01:44:25 +0100