#ifdef CONFIG_X86_32
/* CLBR_ANY should match all regs platform has. For i386, that's just it */
#define CLBR_ANY ((1 << 4) - 1)
+
+#define CLBR_ARG_REGS (CLBR_EAX | CLBR_EDX | CLBR_ECX)
+#define CLBR_RET_REG (CLBR_EAX)
+#define CLBR_SCRATCH (0)
#else
#define CLBR_RAX CLBR_EAX
#define CLBR_RCX CLBR_ECX
#define CLBR_R9 (1 << 6)
#define CLBR_R10 (1 << 7)
#define CLBR_R11 (1 << 8)
+
#define CLBR_ANY ((1 << 9) - 1)
#define CLBR_ARG_REGS (CLBR_RDI | CLBR_RSI | CLBR_RDX | \
CLBR_RCX | CLBR_R8 | CLBR_R9)
-#define CLBR_RET_REG (CLBR_RAX | CLBR_RDX)
+#define CLBR_RET_REG (CLBR_RAX)
#define CLBR_SCRATCH (CLBR_R10 | CLBR_R11)
#include <asm/desc_defs.h>
#endif /* X86_64 */
+#define CLBR_CALLEE_SAVE ((CLBR_ARG_REGS | CLBR_SCRATCH) & ~CLBR_RET_REG)
+
#ifndef __ASSEMBLY__
#include <linux/types.h>
#include <linux/cpumask.h>
struct mm_struct;
struct desc_struct;
+/*
+ * Wrapper type for pointers to code which uses the non-standard
+ * calling convention. See PV_CALL_SAVE_REGS_THUNK below.
+ */
+struct paravirt_callee_save {
+ void *func;
+};
+
/* general info */
struct pv_info {
unsigned int kernel_rpl;
* expected to use X86_EFLAGS_IF; all other bits
* returned from save_fl are undefined, and may be ignored by
* restore_fl.
+ *
+ * NOTE: These functions callers expect the callee to preserve
+ * more registers than the standard C calling convention.
*/
- unsigned long (*save_fl)(void);
- void (*restore_fl)(unsigned long);
- void (*irq_disable)(void);
- void (*irq_enable)(void);
+ struct paravirt_callee_save save_fl;
+ struct paravirt_callee_save restore_fl;
+ struct paravirt_callee_save irq_disable;
+ struct paravirt_callee_save irq_enable;
+
void (*safe_halt)(void);
void (*halt)(void);
__parainstructions_end[];
#ifdef CONFIG_X86_32
-#define PV_SAVE_REGS "pushl %%ecx; pushl %%edx;"
-#define PV_RESTORE_REGS "popl %%edx; popl %%ecx"
+#define PV_SAVE_REGS "pushl %ecx; pushl %edx;"
+#define PV_RESTORE_REGS "popl %edx; popl %ecx;"
+
+/* save and restore all caller-save registers, except return value */
+#define PV_SAVE_ALL_CALLER_REGS PV_SAVE_REGS
+#define PV_RESTORE_ALL_CALLER_REGS PV_RESTORE_REGS
+
#define PV_FLAGS_ARG "0"
#define PV_EXTRA_CLOBBERS
#define PV_VEXTRA_CLOBBERS
#else
+/* save and restore all caller-save registers, except return value */
+#define PV_SAVE_ALL_CALLER_REGS \
+ "push %rcx;" \
+ "push %rdx;" \
+ "push %rsi;" \
+ "push %rdi;" \
+ "push %r8;" \
+ "push %r9;" \
+ "push %r10;" \
+ "push %r11;"
+#define PV_RESTORE_ALL_CALLER_REGS \
+ "pop %r11;" \
+ "pop %r10;" \
+ "pop %r9;" \
+ "pop %r8;" \
+ "pop %rdi;" \
+ "pop %rsi;" \
+ "pop %rdx;" \
+ "pop %rcx;"
+
/* We save some registers, but all of them, that's too much. We clobber all
* caller saved registers but the argument parameter */
#define PV_SAVE_REGS "pushq %%rdi;"
#define PV_FLAGS_ARG "D"
#endif
+/*
+ * Generate a thunk around a function which saves all caller-save
+ * registers except for the return value. This allows C functions to
+ * be called from assembler code where fewer than normal registers are
+ * available. It may also help code generation around calls from C
+ * code if the common case doesn't use many registers.
+ *
+ * When a callee is wrapped in a thunk, the caller can assume that all
+ * arg regs and all scratch registers are preserved across the
+ * call. The return value in rax/eax will not be saved, even for void
+ * functions.
+ */
+#define PV_CALLEE_SAVE_REGS_THUNK(func) \
+ extern typeof(func) __raw_callee_save_##func; \
+ static void *__##func##__ __used = func; \
+ \
+ asm(".pushsection .text;" \
+ "__raw_callee_save_" #func ": " \
+ PV_SAVE_ALL_CALLER_REGS \
+ "call " #func ";" \
+ PV_RESTORE_ALL_CALLER_REGS \
+ "ret;" \
+ ".popsection")
+
+/* Get a reference to a callee-save function */
+#define PV_CALLEE_SAVE(func) \
+ ((struct paravirt_callee_save) { __raw_callee_save_##func })
+
+/* Promise that "func" already uses the right calling convention */
+#define __PV_IS_CALLEE_SAVE(func) \
+ ((struct paravirt_callee_save) { func })
+
static inline unsigned long __raw_local_save_flags(void)
{
unsigned long f;
- asm volatile(paravirt_alt(PV_SAVE_REGS
- PARAVIRT_CALL
- PV_RESTORE_REGS)
+ asm volatile(paravirt_alt(PARAVIRT_CALL)
: "=a"(f)
: paravirt_type(pv_irq_ops.save_fl),
paravirt_clobber(CLBR_EAX)
- : "memory", "cc" PV_VEXTRA_CLOBBERS);
+ : "memory", "cc");
return f;
}
static inline void raw_local_irq_restore(unsigned long f)
{
- asm volatile(paravirt_alt(PV_SAVE_REGS
- PARAVIRT_CALL
- PV_RESTORE_REGS)
+ asm volatile(paravirt_alt(PARAVIRT_CALL)
: "=a"(f)
: PV_FLAGS_ARG(f),
paravirt_type(pv_irq_ops.restore_fl),
paravirt_clobber(CLBR_EAX)
- : "memory", "cc" PV_EXTRA_CLOBBERS);
+ : "memory", "cc");
}
static inline void raw_local_irq_disable(void)
{
- asm volatile(paravirt_alt(PV_SAVE_REGS
- PARAVIRT_CALL
- PV_RESTORE_REGS)
+ asm volatile(paravirt_alt(PARAVIRT_CALL)
:
: paravirt_type(pv_irq_ops.irq_disable),
paravirt_clobber(CLBR_EAX)
- : "memory", "eax", "cc" PV_EXTRA_CLOBBERS);
+ : "memory", "eax", "cc");
}
static inline void raw_local_irq_enable(void)
{
- asm volatile(paravirt_alt(PV_SAVE_REGS
- PARAVIRT_CALL
- PV_RESTORE_REGS)
+ asm volatile(paravirt_alt(PARAVIRT_CALL)
:
: paravirt_type(pv_irq_ops.irq_enable),
paravirt_clobber(CLBR_EAX)
- : "memory", "eax", "cc" PV_EXTRA_CLOBBERS);
+ : "memory", "eax", "cc");
}
static inline unsigned long __raw_local_irq_save(void)
#define COND_PUSH(set, mask, reg) \
- .if ((~set) & mask); push %reg; .endif
+ .if ((~(set)) & mask); push %reg; .endif
#define COND_POP(set, mask, reg) \
- .if ((~set) & mask); pop %reg; .endif
+ .if ((~(set)) & mask); pop %reg; .endif
#ifdef CONFIG_X86_64
#define DISABLE_INTERRUPTS(clobbers) \
PARA_SITE(PARA_PATCH(pv_irq_ops, PV_IRQ_irq_disable), clobbers, \
- PV_SAVE_REGS(clobbers); \
+ PV_SAVE_REGS(clobbers | CLBR_CALLEE_SAVE); \
call PARA_INDIRECT(pv_irq_ops+PV_IRQ_irq_disable); \
- PV_RESTORE_REGS(clobbers);)
+ PV_RESTORE_REGS(clobbers | CLBR_CALLEE_SAVE);)
#define ENABLE_INTERRUPTS(clobbers) \
PARA_SITE(PARA_PATCH(pv_irq_ops, PV_IRQ_irq_enable), clobbers, \
- PV_SAVE_REGS(clobbers); \
+ PV_SAVE_REGS(clobbers | CLBR_CALLEE_SAVE); \
call PARA_INDIRECT(pv_irq_ops+PV_IRQ_irq_enable); \
- PV_RESTORE_REGS(clobbers);)
+ PV_RESTORE_REGS(clobbers | CLBR_CALLEE_SAVE);)
#define USERGS_SYSRET32 \
PARA_SITE(PARA_PATCH(pv_cpu_ops, PV_CPU_usergs_sysret32), \
{
return lguest_data.irq_enabled;
}
+PV_CALLEE_SAVE_REGS_THUNK(save_fl);
/* restore_flags() just sets the flags back to the value given. */
static void restore_fl(unsigned long flags)
{
lguest_data.irq_enabled = flags;
}
+PV_CALLEE_SAVE_REGS_THUNK(restore_fl);
/* Interrupts go off... */
static void irq_disable(void)
{
lguest_data.irq_enabled = 0;
}
+PV_CALLEE_SAVE_REGS_THUNK(irq_disable);
/* Interrupts go on... */
static void irq_enable(void)
{
lguest_data.irq_enabled = X86_EFLAGS_IF;
}
+PV_CALLEE_SAVE_REGS_THUNK(irq_enable);
+
/*:*/
/*M:003 Note that we don't check for outstanding interrupts when we re-enable
* them (or when we unmask an interrupt). This seems to work for the moment,
/* interrupt-related operations */
pv_irq_ops.init_IRQ = lguest_init_IRQ;
- pv_irq_ops.save_fl = save_fl;
- pv_irq_ops.restore_fl = restore_fl;
- pv_irq_ops.irq_disable = irq_disable;
- pv_irq_ops.irq_enable = irq_enable;
+ pv_irq_ops.save_fl = PV_CALLEE_SAVE(save_fl);
+ pv_irq_ops.restore_fl = PV_CALLEE_SAVE(restore_fl);
+ pv_irq_ops.irq_disable = PV_CALLEE_SAVE(irq_disable);
+ pv_irq_ops.irq_enable = PV_CALLEE_SAVE(irq_enable);
pv_irq_ops.safe_halt = lguest_safe_halt;
/* init-time operations */
*/
return (-flags) & X86_EFLAGS_IF;
}
+PV_CALLEE_SAVE_REGS_THUNK(xen_save_fl);
static void xen_restore_fl(unsigned long flags)
{
xen_force_evtchn_callback();
}
}
+PV_CALLEE_SAVE_REGS_THUNK(xen_restore_fl);
static void xen_irq_disable(void)
{
percpu_read(xen_vcpu)->evtchn_upcall_mask = 1;
preempt_enable_no_resched();
}
+PV_CALLEE_SAVE_REGS_THUNK(xen_irq_disable);
static void xen_irq_enable(void)
{
if (unlikely(vcpu->evtchn_upcall_pending))
xen_force_evtchn_callback();
}
+PV_CALLEE_SAVE_REGS_THUNK(xen_irq_enable);
static void xen_safe_halt(void)
{
static const struct pv_irq_ops xen_irq_ops __initdata = {
.init_IRQ = __xen_init_IRQ,
- .save_fl = xen_save_fl,
- .restore_fl = xen_restore_fl,
- .irq_disable = xen_irq_disable,
- .irq_enable = xen_irq_enable,
+
+ .save_fl = PV_CALLEE_SAVE(xen_save_fl),
+ .restore_fl = PV_CALLEE_SAVE(xen_restore_fl),
+ .irq_disable = PV_CALLEE_SAVE(xen_irq_disable),
+ .irq_enable = PV_CALLEE_SAVE(xen_irq_enable),
+
.safe_halt = xen_safe_halt,
.halt = xen_halt,
#ifdef CONFIG_X86_64
projects / GitHub / LineageOS / android_kernel_samsung_universal7580.git / commitdiff