paravirt_types.h

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#ifndef _ASM_X86_PARAVIRT_TYPES_H
#define _ASM_X86_PARAVIRT_TYPES_H

/* Bitmask of what can be clobbered: usually at least eax. */
#define CLBR_NONE 0
#define CLBR_EAX  (1 << 0)
#define CLBR_ECX  (1 << 1)
#define CLBR_EDX  (1 << 2)
#define CLBR_EDI  (1 << 3)

#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 | CLBR_EDX)
#define CLBR_SCRATCH    (0)
#else
#define CLBR_RAX  CLBR_EAX
#define CLBR_RCX  CLBR_ECX
#define CLBR_RDX  CLBR_EDX
#define CLBR_RDI  CLBR_EDI
#define CLBR_RSI  (1 << 4)
#define CLBR_R8   (1 << 5)
#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)
#define CLBR_SCRATCH    (CLBR_R10 | CLBR_R11)

#endif /* X86_64 */

#define CLBR_CALLEE_SAVE ((CLBR_ARG_REGS | CLBR_SCRATCH) & ~CLBR_RET_REG)

#ifndef __ASSEMBLY__

#include <asm/desc_defs.h>
#include <asm/kmap_types.h>
#include <asm/pgtable_types.h>

struct page;
struct thread_struct;
struct desc_ptr;
struct tss_struct;
struct mm_struct;
struct desc_struct;
struct task_struct;
struct cpumask;

/*
 * 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;
    int shared_kernel_pmd;

#ifdef CONFIG_X86_64
    u16 extra_user_64bit_cs;  /* __USER_CS if none */
#endif

    int paravirt_enabled;
    const char *name;
};

struct pv_init_ops {
    /*
     * Patch may replace one of the defined code sequences with
     * arbitrary code, subject to the same register constraints.
     * This generally means the code is not free to clobber any
     * registers other than EAX.  The patch function should return
     * the number of bytes of code generated, as we nop pad the
     * rest in generic code.
     */
    unsigned (*patch)(u8 type, u16 clobber, void *insnbuf,
              unsigned long addr, unsigned len);
};


struct pv_lazy_ops {
    /* Set deferred update mode, used for batching operations. */
    void (*enter)(void);
    void (*leave)(void);
};

struct pv_time_ops {
    unsigned long long (*sched_clock)(void);
    unsigned long long (*steal_clock)(int cpu);
    unsigned long (*get_tsc_khz)(void);
};

struct pv_cpu_ops {
    /* hooks for various privileged instructions */
    unsigned long (*get_debugreg)(int regno);
    void (*set_debugreg)(int regno, unsigned long value);

    void (*clts)(void);

    unsigned long (*read_cr0)(void);
    void (*write_cr0)(unsigned long);

    unsigned long (*read_cr4_safe)(void);
    unsigned long (*read_cr4)(void);
    void (*write_cr4)(unsigned long);

#ifdef CONFIG_X86_64
    unsigned long (*read_cr8)(void);
    void (*write_cr8)(unsigned long);
#endif

    /* Segment descriptor handling */
    void (*load_tr_desc)(void);
    void (*load_gdt)(const struct desc_ptr *);
    void (*load_idt)(const struct desc_ptr *);
    void (*store_gdt)(struct desc_ptr *);
    void (*store_idt)(struct desc_ptr *);
    void (*set_ldt)(const void *desc, unsigned entries);
    unsigned long (*store_tr)(void);
    void (*load_tls)(struct thread_struct *t, unsigned int cpu);
#ifdef CONFIG_X86_64
    void (*load_gs_index)(unsigned int idx);
#endif
    void (*write_ldt_entry)(struct desc_struct *ldt, int entrynum,
                const void *desc);
    void (*write_gdt_entry)(struct desc_struct *,
                int entrynum, const void *desc, int size);
    void (*write_idt_entry)(gate_desc *,
                int entrynum, const gate_desc *gate);
    void (*alloc_ldt)(struct desc_struct *ldt, unsigned entries);
    void (*free_ldt)(struct desc_struct *ldt, unsigned entries);

    void (*load_sp0)(struct tss_struct *tss, struct thread_struct *t);

    void (*set_iopl_mask)(unsigned mask);

    void (*wbinvd)(void);
    void (*io_delay)(void);

    /* cpuid emulation, mostly so that caps bits can be disabled */
    void (*cpuid)(unsigned int *eax, unsigned int *ebx,
              unsigned int *ecx, unsigned int *edx);

    /* MSR, PMC and TSR operations.
       err = 0/-EFAULT.  wrmsr returns 0/-EFAULT. */
    u64 (*read_msr)(unsigned int msr, int *err);
    int (*write_msr)(unsigned int msr, unsigned low, unsigned high);

    u64 (*read_tsc)(void);
    u64 (*read_pmc)(int counter);
    unsigned long long (*read_tscp)(unsigned int *aux);

    /*
     * Atomically enable interrupts and return to userspace.  This
     * is only ever used to return to 32-bit processes; in a
     * 64-bit kernel, it's used for 32-on-64 compat processes, but
     * never native 64-bit processes.  (Jump, not call.)
     */
    void (*irq_enable_sysexit)(void);

    /*
     * Switch to usermode gs and return to 64-bit usermode using
     * sysret.  Only used in 64-bit kernels to return to 64-bit
     * processes.  Usermode register state, including %rsp, must
     * already be restored.
     */
    void (*usergs_sysret64)(void);

    /*
     * Switch to usermode gs and return to 32-bit usermode using
     * sysret.  Used to return to 32-on-64 compat processes.
     * Other usermode register state, including %esp, must already
     * be restored.
     */
    void (*usergs_sysret32)(void);

    /* Normal iret.  Jump to this with the standard iret stack
       frame set up. */
    void (*iret)(void);

    void (*swapgs)(void);

    void (*start_context_switch)(struct task_struct *prev);
    void (*end_context_switch)(struct task_struct *next);
};

struct pv_irq_ops {
    /*
     * Get/set interrupt state.  save_fl and restore_fl are only
     * 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.
     */
    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);

#ifdef CONFIG_X86_64
    void (*adjust_exception_frame)(void);
#endif
};

struct pv_apic_ops {
#ifdef CONFIG_X86_LOCAL_APIC
    void (*startup_ipi_hook)(int phys_apicid,
                 unsigned long start_eip,
                 unsigned long start_esp);
#endif
};

struct pv_mmu_ops {
    unsigned long (*read_cr2)(void);
    void (*write_cr2)(unsigned long);

    unsigned long (*read_cr3)(void);
    void (*write_cr3)(unsigned long);

    /*
     * Hooks for intercepting the creation/use/destruction of an
     * mm_struct.
     */
    void (*activate_mm)(struct mm_struct *prev,
                struct mm_struct *next);
    void (*dup_mmap)(struct mm_struct *oldmm,
             struct mm_struct *mm);
    void (*exit_mmap)(struct mm_struct *mm);


    /* TLB operations */
    void (*flush_tlb_user)(void);
    void (*flush_tlb_kernel)(void);
    void (*flush_tlb_single)(unsigned long addr);
    void (*flush_tlb_others)(const struct cpumask *cpus,
                 struct mm_struct *mm,
                 unsigned long start,
                 unsigned long end);

    /* Hooks for allocating and freeing a pagetable top-level */
    int  (*pgd_alloc)(struct mm_struct *mm);
    void (*pgd_free)(struct mm_struct *mm, pgd_t *pgd);

    /*
     * Hooks for allocating/releasing pagetable pages when they're
     * attached to a pagetable
     */
    void (*alloc_pte)(struct mm_struct *mm, unsigned long pfn);
    void (*alloc_pmd)(struct mm_struct *mm, unsigned long pfn);
    void (*alloc_pud)(struct mm_struct *mm, unsigned long pfn);
    void (*release_pte)(unsigned long pfn);
    void (*release_pmd)(unsigned long pfn);
    void (*release_pud)(unsigned long pfn);

    /* Pagetable manipulation functions */
    void (*set_pte)(pte_t *ptep, pte_t pteval);
    void (*set_pte_at)(struct mm_struct *mm, unsigned long addr,
               pte_t *ptep, pte_t pteval);
    void (*set_pmd)(pmd_t *pmdp, pmd_t pmdval);
    void (*set_pmd_at)(struct mm_struct *mm, unsigned long addr,
               pmd_t *pmdp, pmd_t pmdval);
    void (*pte_update)(struct mm_struct *mm, unsigned long addr,
               pte_t *ptep);
    void (*pte_update_defer)(struct mm_struct *mm,
                 unsigned long addr, pte_t *ptep);
    void (*pmd_update)(struct mm_struct *mm, unsigned long addr,
               pmd_t *pmdp);
    void (*pmd_update_defer)(struct mm_struct *mm,
                 unsigned long addr, pmd_t *pmdp);

    pte_t (*ptep_modify_prot_start)(struct mm_struct *mm, unsigned long addr,
                    pte_t *ptep);
    void (*ptep_modify_prot_commit)(struct mm_struct *mm, unsigned long addr,
                    pte_t *ptep, pte_t pte);

    struct paravirt_callee_save pte_val;
    struct paravirt_callee_save make_pte;

    struct paravirt_callee_save pgd_val;
    struct paravirt_callee_save make_pgd;

#if PAGETABLE_LEVELS >= 3
#ifdef CONFIG_X86_PAE
    void (*set_pte_atomic)(pte_t *ptep, pte_t pteval);
    void (*pte_clear)(struct mm_struct *mm, unsigned long addr,
              pte_t *ptep);
    void (*pmd_clear)(pmd_t *pmdp);

#endif  /* CONFIG_X86_PAE */

    void (*set_pud)(pud_t *pudp, pud_t pudval);

    struct paravirt_callee_save pmd_val;
    struct paravirt_callee_save make_pmd;

#if PAGETABLE_LEVELS == 4
    struct paravirt_callee_save pud_val;
    struct paravirt_callee_save make_pud;

    void (*set_pgd)(pgd_t *pudp, pgd_t pgdval);
#endif  /* PAGETABLE_LEVELS == 4 */
#endif  /* PAGETABLE_LEVELS >= 3 */

    struct pv_lazy_ops lazy_mode;

    /* dom0 ops */

    /* Sometimes the physical address is a pfn, and sometimes its
       an mfn.  We can tell which is which from the index. */
    void (*set_fixmap)(unsigned /* enum fixed_addresses */ idx,
               phys_addr_t phys, pgprot_t flags);
};

struct arch_spinlock;
struct pv_lock_ops {
    int (*spin_is_locked)(struct arch_spinlock *lock);
    int (*spin_is_contended)(struct arch_spinlock *lock);
    void (*spin_lock)(struct arch_spinlock *lock);
    void (*spin_lock_flags)(struct arch_spinlock *lock, unsigned long flags);
    int (*spin_trylock)(struct arch_spinlock *lock);
    void (*spin_unlock)(struct arch_spinlock *lock);
};

/* This contains all the paravirt structures: we get a convenient
 * number for each function using the offset which we use to indicate
 * what to patch. */
struct paravirt_patch_template {
    struct pv_init_ops pv_init_ops;
    struct pv_time_ops pv_time_ops;
    struct pv_cpu_ops pv_cpu_ops;
    struct pv_irq_ops pv_irq_ops;
    struct pv_apic_ops pv_apic_ops;
    struct pv_mmu_ops pv_mmu_ops;
    struct pv_lock_ops pv_lock_ops;
};

extern struct pv_info pv_info;
extern struct pv_init_ops pv_init_ops;
extern struct pv_time_ops pv_time_ops;
extern struct pv_cpu_ops pv_cpu_ops;
extern struct pv_irq_ops pv_irq_ops;
extern struct pv_apic_ops pv_apic_ops;
extern struct pv_mmu_ops pv_mmu_ops;
extern struct pv_lock_ops pv_lock_ops;

#define PARAVIRT_PATCH(x)                   \
    (offsetof(struct paravirt_patch_template, x) / sizeof(void *))

#define paravirt_type(op)               \
    [paravirt_typenum] "i" (PARAVIRT_PATCH(op)),    \
    [paravirt_opptr] "i" (&(op))
#define paravirt_clobber(clobber)       \
    [paravirt_clobber] "i" (clobber)

/*
 * Generate some code, and mark it as patchable by the
 * apply_paravirt() alternate instruction patcher.
 */
#define _paravirt_alt(insn_string, type, clobber)   \
    "771:\n\t" insn_string "\n" "772:\n"        \
    ".pushsection .parainstructions,\"a\"\n"    \
    _ASM_ALIGN "\n"                 \
    _ASM_PTR " 771b\n"              \
    "  .byte " type "\n"                \
    "  .byte 772b-771b\n"               \
    "  .short " clobber "\n"            \
    ".popsection\n"

/* Generate patchable code, with the default asm parameters. */
#define paravirt_alt(insn_string)                   \
    _paravirt_alt(insn_string, "%c[paravirt_typenum]", "%c[paravirt_clobber]")

/* Simple instruction patching code. */
#define DEF_NATIVE(ops, name, code)                     \
    extern const char start_##ops##_##name[], end_##ops##_##name[]; \
    asm("start_" #ops "_" #name ": " code "; end_" #ops "_" #name ":")

unsigned paravirt_patch_nop(void);
unsigned paravirt_patch_ident_32(void *insnbuf, unsigned len);
unsigned paravirt_patch_ident_64(void *insnbuf, unsigned len);
unsigned paravirt_patch_ignore(unsigned len);
unsigned paravirt_patch_call(void *insnbuf,
                 const void *target, u16 tgt_clobbers,
                 unsigned long addr, u16 site_clobbers,
                 unsigned len);
unsigned paravirt_patch_jmp(void *insnbuf, const void *target,
                unsigned long addr, unsigned len);
unsigned paravirt_patch_default(u8 type, u16 clobbers, void *insnbuf,
                unsigned long addr, unsigned len);

unsigned paravirt_patch_insns(void *insnbuf, unsigned len,
                  const char *start, const char *end);

unsigned native_patch(u8 type, u16 clobbers, void *ibuf,
              unsigned long addr, unsigned len);

int paravirt_disable_iospace(void);

/*
 * This generates an indirect call based on the operation type number.
 * The type number, computed in PARAVIRT_PATCH, is derived from the
 * offset into the paravirt_patch_template structure, and can therefore be
 * freely converted back into a structure offset.
 */
#define PARAVIRT_CALL   "call *%c[paravirt_opptr];"

/*
 * These macros are intended to wrap calls through one of the paravirt
 * ops structs, so that they can be later identified and patched at
 * runtime.
 *
 * Normally, a call to a pv_op function is a simple indirect call:
 * (pv_op_struct.operations)(args...).
 *
 * Unfortunately, this is a relatively slow operation for modern CPUs,
 * because it cannot necessarily determine what the destination
 * address is.  In this case, the address is a runtime constant, so at
 * the very least we can patch the call to e a simple direct call, or
 * ideally, patch an inline implementation into the callsite.  (Direct
 * calls are essentially free, because the call and return addresses
 * are completely predictable.)
 *
 * For i386, these macros rely on the standard gcc "regparm(3)" calling
 * convention, in which the first three arguments are placed in %eax,
 * %edx, %ecx (in that order), and the remaining arguments are placed
 * on the stack.  All caller-save registers (eax,edx,ecx) are expected
 * to be modified (either clobbered or used for return values).
 * X86_64, on the other hand, already specifies a register-based calling
 * conventions, returning at %rax, with parameteres going on %rdi, %rsi,
 * %rdx, and %rcx. Note that for this reason, x86_64 does not need any
 * special handling for dealing with 4 arguments, unlike i386.
 * However, x86_64 also have to clobber all caller saved registers, which
 * unfortunately, are quite a bit (r8 - r11)
 *
 * The call instruction itself is marked by placing its start address
 * and size into the .parainstructions section, so that
 * apply_paravirt() in arch/i386/kernel/alternative.c can do the
 * appropriate patching under the control of the backend pv_init_ops
 * implementation.
 *
 * Unfortunately there's no way to get gcc to generate the args setup
 * for the call, and then allow the call itself to be generated by an
 * inline asm.  Because of this, we must do the complete arg setup and
 * return value handling from within these macros.  This is fairly
 * cumbersome.
 *
 * There are 5 sets of PVOP_* macros for dealing with 0-4 arguments.
 * It could be extended to more arguments, but there would be little
 * to be gained from that.  For each number of arguments, there are
 * the two VCALL and CALL variants for void and non-void functions.
 *
 * When there is a return value, the invoker of the macro must specify
 * the return type.  The macro then uses sizeof() on that type to
 * determine whether its a 32 or 64 bit value, and places the return
 * in the right register(s) (just %eax for 32-bit, and %edx:%eax for
 * 64-bit). For x86_64 machines, it just returns at %rax regardless of
 * the return value size.
 *
 * 64-bit arguments are passed as a pair of adjacent 32-bit arguments
 * i386 also passes 64-bit arguments as a pair of adjacent 32-bit arguments
 * in low,high order
 *
 * Small structures are passed and returned in registers.  The macro
 * calling convention can't directly deal with this, so the wrapper
 * functions must do this.
 *
 * These PVOP_* macros are only defined within this header.  This
 * means that all uses must be wrapped in inline functions.  This also
 * makes sure the incoming and outgoing types are always correct.
 */
#ifdef CONFIG_X86_32
#define PVOP_VCALL_ARGS             \
    unsigned long __eax = __eax, __edx = __edx, __ecx = __ecx
#define PVOP_CALL_ARGS          PVOP_VCALL_ARGS

#define PVOP_CALL_ARG1(x)       "a" ((unsigned long)(x))
#define PVOP_CALL_ARG2(x)       "d" ((unsigned long)(x))
#define PVOP_CALL_ARG3(x)       "c" ((unsigned long)(x))

#define PVOP_VCALL_CLOBBERS     "=a" (__eax), "=d" (__edx), \
                    "=c" (__ecx)
#define PVOP_CALL_CLOBBERS      PVOP_VCALL_CLOBBERS

#define PVOP_VCALLEE_CLOBBERS       "=a" (__eax), "=d" (__edx)
#define PVOP_CALLEE_CLOBBERS        PVOP_VCALLEE_CLOBBERS

#define EXTRA_CLOBBERS
#define VEXTRA_CLOBBERS
#else  /* CONFIG_X86_64 */
/* [re]ax isn't an arg, but the return val */
#define PVOP_VCALL_ARGS                 \
    unsigned long __edi = __edi, __esi = __esi, \
        __edx = __edx, __ecx = __ecx, __eax = __eax
#define PVOP_CALL_ARGS      PVOP_VCALL_ARGS

#define PVOP_CALL_ARG1(x)       "D" ((unsigned long)(x))
#define PVOP_CALL_ARG2(x)       "S" ((unsigned long)(x))
#define PVOP_CALL_ARG3(x)       "d" ((unsigned long)(x))
#define PVOP_CALL_ARG4(x)       "c" ((unsigned long)(x))

#define PVOP_VCALL_CLOBBERS "=D" (__edi),               \
                "=S" (__esi), "=d" (__edx),     \
                "=c" (__ecx)
#define PVOP_CALL_CLOBBERS  PVOP_VCALL_CLOBBERS, "=a" (__eax)

/* void functions are still allowed [re]ax for scratch */
#define PVOP_VCALLEE_CLOBBERS   "=a" (__eax)
#define PVOP_CALLEE_CLOBBERS    PVOP_VCALLEE_CLOBBERS

#define EXTRA_CLOBBERS   , "r8", "r9", "r10", "r11"
#define VEXTRA_CLOBBERS  , "rax", "r8", "r9", "r10", "r11"
#endif  /* CONFIG_X86_32 */

#ifdef CONFIG_PARAVIRT_DEBUG
#define PVOP_TEST_NULL(op)  BUG_ON(op == NULL)
#else
#define PVOP_TEST_NULL(op)  ((void)op)
#endif

#define ____PVOP_CALL(rettype, op, clbr, call_clbr, extra_clbr,     \
              pre, post, ...)                   \
    ({                              \
        rettype __ret;                      \
        PVOP_CALL_ARGS;                     \
        PVOP_TEST_NULL(op);                 \
        /* This is 32-bit specific, but is okay in 64-bit */    \
        /* since this condition will never hold */      \
        if (sizeof(rettype) > sizeof(unsigned long)) {      \
            asm volatile(pre                \
                     paravirt_alt(PARAVIRT_CALL)    \
                     post               \
                     : call_clbr            \
                     : paravirt_type(op),       \
                       paravirt_clobber(clbr),      \
                       ##__VA_ARGS__            \
                     : "memory", "cc" extra_clbr);  \
            __ret = (rettype)((((u64)__edx) << 32) | __eax); \
        } else {                        \
            asm volatile(pre                \
                     paravirt_alt(PARAVIRT_CALL)    \
                     post               \
                     : call_clbr            \
                     : paravirt_type(op),       \
                       paravirt_clobber(clbr),      \
                       ##__VA_ARGS__            \
                     : "memory", "cc" extra_clbr);  \
            __ret = (rettype)__eax;             \
        }                           \
        __ret;                          \
    })

#define __PVOP_CALL(rettype, op, pre, post, ...)            \
    ____PVOP_CALL(rettype, op, CLBR_ANY, PVOP_CALL_CLOBBERS,    \
              EXTRA_CLOBBERS, pre, post, ##__VA_ARGS__)

#define __PVOP_CALLEESAVE(rettype, op, pre, post, ...)          \
    ____PVOP_CALL(rettype, op.func, CLBR_RET_REG,           \
              PVOP_CALLEE_CLOBBERS, ,               \
              pre, post, ##__VA_ARGS__)


#define ____PVOP_VCALL(op, clbr, call_clbr, extra_clbr, pre, post, ...) \
    ({                              \
        PVOP_VCALL_ARGS;                    \
        PVOP_TEST_NULL(op);                 \
        asm volatile(pre                    \
                 paravirt_alt(PARAVIRT_CALL)        \
                 post                   \
                 : call_clbr                \
                 : paravirt_type(op),           \
                   paravirt_clobber(clbr),          \
                   ##__VA_ARGS__                \
                 : "memory", "cc" extra_clbr);      \
    })

#define __PVOP_VCALL(op, pre, post, ...)                \
    ____PVOP_VCALL(op, CLBR_ANY, PVOP_VCALL_CLOBBERS,       \
               VEXTRA_CLOBBERS,                 \
               pre, post, ##__VA_ARGS__)

#define __PVOP_VCALLEESAVE(op, pre, post, ...)              \
    ____PVOP_VCALL(op.func, CLBR_RET_REG,               \
              PVOP_VCALLEE_CLOBBERS, ,              \
              pre, post, ##__VA_ARGS__)



#define PVOP_CALL0(rettype, op)                     \
    __PVOP_CALL(rettype, op, "", "")
#define PVOP_VCALL0(op)                         \
    __PVOP_VCALL(op, "", "")

#define PVOP_CALLEE0(rettype, op)                   \
    __PVOP_CALLEESAVE(rettype, op, "", "")
#define PVOP_VCALLEE0(op)                       \
    __PVOP_VCALLEESAVE(op, "", "")


#define PVOP_CALL1(rettype, op, arg1)                   \
    __PVOP_CALL(rettype, op, "", "", PVOP_CALL_ARG1(arg1))
#define PVOP_VCALL1(op, arg1)                       \
    __PVOP_VCALL(op, "", "", PVOP_CALL_ARG1(arg1))

#define PVOP_CALLEE1(rettype, op, arg1)                 \
    __PVOP_CALLEESAVE(rettype, op, "", "", PVOP_CALL_ARG1(arg1))
#define PVOP_VCALLEE1(op, arg1)                     \
    __PVOP_VCALLEESAVE(op, "", "", PVOP_CALL_ARG1(arg1))


#define PVOP_CALL2(rettype, op, arg1, arg2)             \
    __PVOP_CALL(rettype, op, "", "", PVOP_CALL_ARG1(arg1),      \
            PVOP_CALL_ARG2(arg2))
#define PVOP_VCALL2(op, arg1, arg2)                 \
    __PVOP_VCALL(op, "", "", PVOP_CALL_ARG1(arg1),          \
             PVOP_CALL_ARG2(arg2))

#define PVOP_CALLEE2(rettype, op, arg1, arg2)               \
    __PVOP_CALLEESAVE(rettype, op, "", "", PVOP_CALL_ARG1(arg1),    \
              PVOP_CALL_ARG2(arg2))
#define PVOP_VCALLEE2(op, arg1, arg2)                   \
    __PVOP_VCALLEESAVE(op, "", "", PVOP_CALL_ARG1(arg1),        \
               PVOP_CALL_ARG2(arg2))


#define PVOP_CALL3(rettype, op, arg1, arg2, arg3)           \
    __PVOP_CALL(rettype, op, "", "", PVOP_CALL_ARG1(arg1),      \
            PVOP_CALL_ARG2(arg2), PVOP_CALL_ARG3(arg3))
#define PVOP_VCALL3(op, arg1, arg2, arg3)               \
    __PVOP_VCALL(op, "", "", PVOP_CALL_ARG1(arg1),          \
             PVOP_CALL_ARG2(arg2), PVOP_CALL_ARG3(arg3))

/* This is the only difference in x86_64. We can make it much simpler */
#ifdef CONFIG_X86_32
#define PVOP_CALL4(rettype, op, arg1, arg2, arg3, arg4)         \
    __PVOP_CALL(rettype, op,                    \
            "push %[_arg4];", "lea 4(%%esp),%%esp;",        \
            PVOP_CALL_ARG1(arg1), PVOP_CALL_ARG2(arg2),     \
            PVOP_CALL_ARG3(arg3), [_arg4] "mr" ((u32)(arg4)))
#define PVOP_VCALL4(op, arg1, arg2, arg3, arg4)             \
    __PVOP_VCALL(op,                        \
            "push %[_arg4];", "lea 4(%%esp),%%esp;",        \
            "0" ((u32)(arg1)), "1" ((u32)(arg2)),       \
            "2" ((u32)(arg3)), [_arg4] "mr" ((u32)(arg4)))
#else
#define PVOP_CALL4(rettype, op, arg1, arg2, arg3, arg4)         \
    __PVOP_CALL(rettype, op, "", "",                \
            PVOP_CALL_ARG1(arg1), PVOP_CALL_ARG2(arg2),     \
            PVOP_CALL_ARG3(arg3), PVOP_CALL_ARG4(arg4))
#define PVOP_VCALL4(op, arg1, arg2, arg3, arg4)             \
    __PVOP_VCALL(op, "", "",                    \
             PVOP_CALL_ARG1(arg1), PVOP_CALL_ARG2(arg2),    \
             PVOP_CALL_ARG3(arg3), PVOP_CALL_ARG4(arg4))
#endif

/* Lazy mode for batching updates / context switch */
enum paravirt_lazy_mode {
    PARAVIRT_LAZY_NONE,
    PARAVIRT_LAZY_MMU,
    PARAVIRT_LAZY_CPU,
};

enum paravirt_lazy_mode paravirt_get_lazy_mode(void);
void paravirt_start_context_switch(struct task_struct *prev);
void paravirt_end_context_switch(struct task_struct *next);

void paravirt_enter_lazy_mmu(void);
void paravirt_leave_lazy_mmu(void);

void _paravirt_nop(void);
u32 _paravirt_ident_32(u32);
u64 _paravirt_ident_64(u64);

#define paravirt_nop    ((void *)_paravirt_nop)

/* These all sit in the .parainstructions section to tell us what to patch. */
struct paravirt_patch_site {
    u8 *instr;      /* original instructions */
    u8 instrtype;       /* type of this instruction */
    u8 len;         /* length of original instruction */
    u16 clobbers;       /* what registers you may clobber */
};

extern struct paravirt_patch_site __parainstructions[],
    __parainstructions_end[];

#endif  /* __ASSEMBLY__ */

#endif  /* _ASM_X86_PARAVIRT_TYPES_H */