#ifndef _ASM_X86_EFI_H
#define _ASM_X86_EFI_H
#include <asm/i387.h>
#include <asm/pgtable.h>
#include <asm/processor-flags.h>
#include <asm/tlb.h>
#include <asm/spec_ctrl.h>
#include <asm/mmu_context.h>
/*
* We map the EFI regions needed for runtime services non-contiguously,
* with preserved alignment on virtual addresses starting from -4G down
* for a total max space of 64G. This way, we provide for stable runtime
* services addresses across kernels so that a kexec'd kernel can still
* use them.
*
* This is the main reason why we're doing stable VA mappings for RT
* services.
*
* This flag is used in conjuction with a chicken bit called
* "efi=old_map" which can be used as a fallback to the old runtime
* services mapping method in case there's some b0rkage with a
* particular EFI implementation (haha, it is hard to hold up the
* sarcasm here...).
*/
#define EFI_OLD_MEMMAP EFI_ARCH_1
#define EFI32_LOADER_SIGNATURE "EL32"
#define EFI64_LOADER_SIGNATURE "EL64"
#define ARCH_EFI_IRQ_FLAGS_MASK X86_EFLAGS_IF
#ifdef CONFIG_X86_32
extern unsigned long asmlinkage efi_call_phys(void *, ...);
#define arch_efi_call_virt_setup() \
{( \
bool ibrs_on; \
kernel_fpu_begin(); \
ibrs_on = unprotected_firmware_begin(); \
ibrs_on; \
)}
#define arch_efi_call_virt_teardown(ibrs_on) \
{( \
unprotected_firmware_end(ibrs_on); \
kernel_fpu_end(); \
)}
/*
* Wrap all the virtual calls in a way that forces the parameters on the stack.
*/
#define arch_efi_call_virt(p, f, args...) \
({ \
((efi_##f##_t __attribute__((regparm(0)))*) p->f)(args); \
})
#define efi_ioremap(addr, size, type, attr) ioremap_cache(addr, size)
#else /* !CONFIG_X86_32 */
#define EFI_LOADER_SIGNATURE "EL64"
extern u64 asmlinkage efi_call(void *fp, ...);
#define efi_call_phys(f, args...) efi_call((f), args)
/*
* struct efi_scratch - Scratch space used while switching to/from efi_mm
* @phys_stack: stack used during EFI Mixed Mode
* @prev_mm: store/restore stolen mm_struct while switching to/from efi_mm
* @cpu_tlbstate: store/restore the previous TLB state (for lazy flushes)
*/
struct efi_scratch {
u64 phys_stack;
struct mm_struct *prev_mm;
int cpu_tlbstate;
} __packed;
/*
* RHEL7: switch_mm() will prematurely flip the cpu_tlbstate back to
* TLBSTATE_OK for the kernel thread servicing EFI stubs, which can
* potentially trigger the assertion at leave_mm(), if the work queued
* to run after the EFI thunk happens to initiate a TLB flush (i.e.:
* if a flush worker is queued after the efivarsfs read/write work).
*
* OTOH, we cannot blindly make the cpu re-enter lazy_tlb state on
* every call to efi_switch_mm(), as it might also cause issues for
* the thread running under efi_mm when it's mapped and operated on.
*
* In order to address these two diametral corner cases, we need to
* save the CPU current TLBSTATE before calling efi_switch_mm(&efi_mm),
* and restore its value after calling efi_switch_mm(efi_scratch.prev_mm);
*/
#define EFI_SAVE_CPU_TLBSTATE() \
({ \
efi_scratch.cpu_tlbstate = this_cpu_read(cpu_tlbstate.state); \
})
#define EFI_RESTORE_CPU_TLBSTATE() \
({ \
this_cpu_write(cpu_tlbstate.state, efi_scratch.cpu_tlbstate); \
})
#define arch_efi_call_virt_setup() \
({ \
bool ibrs_on; \
efi_sync_low_kernel_mappings(); \
preempt_disable(); \
ibrs_on = unprotected_firmware_begin(); \
\
if (!efi_enabled(EFI_OLD_MEMMAP)) { \
EFI_SAVE_CPU_TLBSTATE(); \
efi_switch_mm(&efi_mm); \
} \
ibrs_on; \
})
#define arch_efi_call_virt(p, f, args...) \
efi_call((void *)p->f, args) \
#define arch_efi_call_virt_teardown(ibrs_on) \
({ \
if (!efi_enabled(EFI_OLD_MEMMAP)) { \
efi_switch_mm(efi_scratch.prev_mm); \
EFI_RESTORE_CPU_TLBSTATE(); \
} \
unprotected_firmware_end(ibrs_on); \
preempt_enable(); \
})
extern void __iomem *__init efi_ioremap(unsigned long addr, unsigned long size,
u32 type, u64 attribute);
#endif /* CONFIG_X86_32 */
extern int add_efi_memmap;
extern struct efi_scratch efi_scratch;
extern void __init efi_set_executable(efi_memory_desc_t *md, bool executable);
extern int __init efi_memblock_x86_reserve_range(void);
extern pgd_t * __init efi_call_phys_prolog(void);
extern void __init efi_call_phys_epilog(pgd_t *save_pgd);
extern void __init efi_unmap_memmap(void);
extern void __init efi_memory_uc(u64 addr, unsigned long size);
extern void __init efi_map_region(efi_memory_desc_t *md);
extern void __init efi_map_region_fixed(efi_memory_desc_t *md);
extern void efi_sync_low_kernel_mappings(void);
extern int __init efi_alloc_page_tables(void);
extern int __init efi_setup_page_tables(unsigned long pa_memmap, unsigned num_pages);
extern void __init old_map_region(efi_memory_desc_t *md);
extern void __init efi_dump_pagetable(void);
extern void __init efi_apply_memmap_quirks(void);
extern int __init efi_reuse_config(u64 tables, int nr_tables);
extern void efi_delete_dummy_variable(void);
extern void efi_switch_mm(struct mm_struct *mm);
extern void efi_recover_from_page_fault(unsigned long phys_addr);
struct efi_setup_data {
u64 fw_vendor;
u64 runtime;
u64 tables;
u64 smbios;
u64 reserved[8];
};
extern u64 efi_setup;
#ifdef CONFIG_EFI
static inline bool efi_is_native(void)
{
return IS_ENABLED(CONFIG_X86_64) == efi_enabled(EFI_64BIT);
}
static inline bool efi_runtime_supported(void)
{
if (efi_is_native())
return true;
if (IS_ENABLED(CONFIG_EFI_MIXED) && !efi_enabled(EFI_OLD_MEMMAP))
return true;
return false;
}
extern struct console early_efi_console;
extern void parse_efi_setup(u64 phys_addr, u32 data_len);
#ifdef CONFIG_EFI_MIXED
extern void efi_thunk_runtime_setup(void);
extern efi_status_t efi_thunk_set_virtual_address_map(
void *phys_set_virtual_address_map,
unsigned long memory_map_size,
unsigned long descriptor_size,
u32 descriptor_version,
efi_memory_desc_t *virtual_map);
#else
static inline void efi_thunk_runtime_setup(void) {}
static inline efi_status_t efi_thunk_set_virtual_address_map(
void *phys_set_virtual_address_map,
unsigned long memory_map_size,
unsigned long descriptor_size,
u32 descriptor_version,
efi_memory_desc_t *virtual_map)
{
return EFI_SUCCESS;
}
#endif /* CONFIG_EFI_MIXED */
#else
static inline void parse_efi_setup(u64 phys_addr, u32 data_len) {}
#endif /* CONFIG_EFI */
#endif /* _ASM_X86_EFI_H */
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