efi: Add 'runtime' pointer to struct efi

Instead of going through the EFI system table each time, just copy the runtime services table pointer into struct efi directly. This is the last use of the system table pointer in struct efi, allowing us to drop it in a future patch, along with a fair amount of quirky handling of the translated address. Note that usually, the runtime services pointer changes value during the call to SetVirtualAddressMap(), so grab the updated value as soon as that call returns. (Mixed mode uses a 1:1 mapping, and kexec boot enters with the updated address in the system table, so in those cases, we don't need to do anything here)

Ard Biesheuvel committed 6 years ago

Commit 59f2a611 parent 09308019 files · +49 −22Browse files

Unified · Split

9 files

arch/x86/include/asm/efi.h +2 −1
arch/x86/kernel/asm-offsets_32.c +5 −0
arch/x86/platform/efi/efi.c +6 −3
arch/x86/platform/efi/efi_32.c +8 −5
arch/x86/platform/efi/efi_64.c +8 −6
arch/x86/platform/efi/efi_stub_32.S +16 −5
drivers/firmware/efi/arm-init.c +1 −0
drivers/firmware/efi/runtime-wrappers.c +2 −2
include/linux/efi.h +1 −0

arch/x86/include/asm/efi.h+2−1

@@ -218,7 +218,8 @@ extern void efi_thunk_runtime_setup(void); · 217 unmodified lines
218	218	efi_status_t efi_set_virtual_address_map(unsigned long memory_map_size,
219	219	unsigned long descriptor_size,
220	220	u32 descriptor_version,
221		− efi_memory_desc_t *virtual_map);
	221	+ efi_memory_desc_t *virtual_map,
	222	+ unsigned long systab_phys);
222	223
223	224	/* arch specific definitions used by the stub code */
224	225

arch/x86/kernel/asm-offsets_32.c+5−0

@@ -3,6 +3,8 @@ · 2 unmodified lines
3	3	# error "Please do not build this file directly, build asm-offsets.c instead"
4	4	#endif
5	5
	6	+#include <linux/efi.h>
	7	+
6	8	#include <asm/ucontext.h>
7	9
8	10	#define __SYSCALL_I386(nr, sym, qual) [nr] = 1,
@@ -64,4 +66,7 @@ void foo(void) · 55 unmodified lines
64	66	BLANK();
65	67	DEFINE(__NR_syscall_max, sizeof(syscalls) - 1);
66	68	DEFINE(NR_syscalls, sizeof(syscalls));
	69	+
	70	+ BLANK();
	71	+ DEFINE(EFI_svam, offsetof(efi_runtime_services_t, set_virtual_address_map));
67	72	}

arch/x86/platform/efi/efi.c+6−3

@@ -55,8 +55,8 @@ · 54 unmodified lines
55	55	#include <asm/uv/uv.h>
56	56
57	57	static efi_system_table_t efi_systab __initdata;
58		−static u64 efi_systab_phys __initdata;
59	58
	59	+static unsigned long efi_systab_phys __initdata;
60	60	static unsigned long prop_phys = EFI_INVALID_TABLE_ADDR;
61	61	static unsigned long uga_phys = EFI_INVALID_TABLE_ADDR;
62	62	static unsigned long efi_runtime, efi_nr_tables;
@@ -335,7 +335,7 @@ void __init efi_print_memmap(void) · 272 unmodified lines
335	335	}
336	336	}
337	337
338		−static int __init efi_systab_init(u64 phys)
	338	+static int __init efi_systab_init(unsigned long phys)
339	339	{
340	340	int size = efi_enabled(EFI_64BIT) ? sizeof(efi_system_table_64_t)
341	341	: sizeof(efi_system_table_32_t);
@@ -949,7 +949,8 @@ static void __init __efi_enter_virtual_mode(void) · 607 unmodified lines
949	949	status = efi_set_virtual_address_map(efi.memmap.desc_size * count,
950	950	efi.memmap.desc_size,
951	951	efi.memmap.desc_version,
952		− (efi_memory_desc_t *)pa);
	952	+ (efi_memory_desc_t *)pa,
	953	+ efi_systab_phys);
953	954	if (status != EFI_SUCCESS) {
954	955	pr_err("Unable to switch EFI into virtual mode (status=%lx)!\n",
955	956	status);
@@ -983,6 +984,8 @@ void __init efi_enter_virtual_mode(void) · 27 unmodified lines
983	984	if (efi_enabled(EFI_PARAVIRT))
984	985	return;
985	986
	987	+ efi.runtime = (efi_runtime_services_t *)efi_runtime;
	988	+
986	989	if (efi_setup)
987	990	kexec_enter_virtual_mode();
988	991	else

arch/x86/platform/efi/efi_32.c+8−5

@@ -66,14 +66,16 @@ void __init efi_map_region(efi_memory_desc_t *md) · 65 unmodified lines
66	66	void __init efi_map_region_fixed(efi_memory_desc_t *md) {}
67	67	void __init parse_efi_setup(u64 phys_addr, u32 data_len) {}
68	68
69		−efi_status_t efi_call_svam(efi_set_virtual_address_map_t __efiapi ,
70		− u32, u32, u32, void *);
	69	+efi_status_t efi_call_svam(efi_runtime_services_t * const *,
	70	+ u32, u32, u32, void *, u32);
71	71
72	72	efi_status_t __init efi_set_virtual_address_map(unsigned long memory_map_size,
73	73	unsigned long descriptor_size,
74	74	u32 descriptor_version,
75		− efi_memory_desc_t *virtual_map)
	75	+ efi_memory_desc_t *virtual_map,
	76	+ unsigned long systab_phys)
76	77	{
	78	+ const efi_system_table_t systab = (efi_system_table_t )systab_phys;
77	79	struct desc_ptr gdt_descr;
78	80	efi_status_t status;
79	81	unsigned long flags;
@@ -90,9 +92,10 @@ efi_status_t __init efi_set_virtual_address_map(unsigned long memory_map_size, · 10 unmodified lines
90	92
91	93	/* Disable interrupts around EFI calls: */
92	94	local_irq_save(flags);
93		− status = efi_call_svam(&efi.systab->runtime->set_virtual_address_map,
	95	+ status = efi_call_svam(&systab->runtime,
94	96	memory_map_size, descriptor_size,
95		− descriptor_version, virtual_map);
	97	+ descriptor_version, virtual_map,
	98	+ __pa(&efi.runtime));
96	99	local_irq_restore(flags);
97	100
98	101	load_fixmap_gdt(0);

arch/x86/platform/efi/efi_64.c+8−6

@@ -500,12 +500,9 @@ static DEFINE_SPINLOCK(efi_runtime_lock); · 499 unmodified lines
500	500	*/
501	501	#define __efi_thunk(func, ...) \
502	502	({ \
503		− efi_runtime_services_32_t *__rt; \
504	503	unsigned short __ds, __es; \
505	504	efi_status_t ____s; \
506	505	\
507		− __rt = (void *)(unsigned long)efi.systab->mixed_mode.runtime; \
508		− \
509	506	savesegment(ds, __ds); \
510	507	savesegment(es, __es); \
511	508	\
@@ -513,7 +510,7 @@ static DEFINE_SPINLOCK(efi_runtime_lock); · 1 unmodified line
513	510	loadsegment(ds, __KERNEL_DS); \
514	511	loadsegment(es, __KERNEL_DS); \
515	512	\
516		− ____s = efi64_thunk(__rt->func, __VA_ARGS__); \
	513	+ ____s = efi64_thunk(efi.runtime->mixed_mode.func, __VA_ARGS__); \
517	514	\
518	515	loadsegment(ds, __ds); \
519	516	loadsegment(es, __es); \
@@ -886,8 +883,10 @@ efi_status_t __init __no_sanitize_address · 366 unmodified lines
886	883	efi_set_virtual_address_map(unsigned long memory_map_size,
887	884	unsigned long descriptor_size,
888	885	u32 descriptor_version,
889		− efi_memory_desc_t *virtual_map)
	886	+ efi_memory_desc_t *virtual_map,
	887	+ unsigned long systab_phys)
890	888	{
	889	+ const efi_system_table_t systab = (efi_system_table_t )systab_phys;
891	890	efi_status_t status;
892	891	unsigned long flags;
893	892	pgd_t *save_pgd = NULL;
@@ -910,13 +909,16 @@ efi_set_virtual_address_map(unsigned long memory_map_size, · 16 unmodified lines
910	909
911	910	/* Disable interrupts around EFI calls: */
912	911	local_irq_save(flags);
913		− status = efi_call(efi.systab->runtime->set_virtual_address_map,
	912	+ status = efi_call(efi.runtime->set_virtual_address_map,
914	913	memory_map_size, descriptor_size,
915	914	descriptor_version, virtual_map);
916	915	local_irq_restore(flags);
917	916
918	917	kernel_fpu_end();
919	918
	919	+ /* grab the virtually remapped EFI runtime services table pointer */
	920	+ efi.runtime = READ_ONCE(systab->runtime);
	921	+
920	922	if (save_pgd)
921	923	efi_uv1_memmap_phys_epilog(save_pgd);
922	924	else

arch/x86/platform/efi/efi_stub_32.S+16−5

@@ -8,14 +8,20 @@ · 7 unmodified lines
8	8
9	9	#include <linux/linkage.h>
10	10	#include <linux/init.h>
	11	+#include <asm/asm-offsets.h>
11	12	#include <asm/page_types.h>
12	13
13	14	__INIT
14	15	SYM_FUNC_START(efi_call_svam)
15		− push 8(%esp)
16		− push 8(%esp)
	16	+ push %ebp
	17	+ movl %esp, %ebp
	18	+ push %ebx
	19	+
	20	+ push 16(%esp)
	21	+ push 16(%esp)
17	22	push %ecx
18	23	push %edx
	24	+ movl %eax, %ebx // &systab_phys->runtime
19	25
20	26	/*
21	27	* Switch to the flat mapped alias of this routine, by jumping to the
@@ -35,15 +41,20 @@ SYM_FUNC_START(efi_call_svam) · 13 unmodified lines
35	41	subl $__PAGE_OFFSET, %esp
36	42
37	43	/* call the EFI routine */
38		− call *(%eax)
	44	+ movl (%eax), %eax
	45	+ call *EFI_svam(%eax)
39	46
40		− /* convert ESP back to a kernel VA, and pop the outgoing args */
41		− addl $__PAGE_OFFSET + 16, %esp
	47	+ /* grab the virtually remapped EFI runtime services table pointer */
	48	+ movl (%ebx), %ecx
	49	+ movl 36(%esp), %edx // &efi.runtime
	50	+ movl %ecx, (%edx)
42	51
43	52	/* re-enable paging */
44	53	movl %cr0, %edx
45	54	orl $0x80000000, %edx
46	55	movl %edx, %cr0
47	56
	57	+ pop %ebx
	58	+ leave
48	59	ret
49	60	SYM_FUNC_END(efi_call_svam)

drivers/firmware/efi/arm-init.c+1−0

@@ -104,6 +104,7 @@ static int __init uefi_init(void) · 103 unmodified lines
104	104	if (retval)
105	105	goto out;
106	106
	107	+ efi.runtime = efi.systab->runtime;
107	108	efi.runtime_version = efi.systab->hdr.revision;
108	109
109	110	efi_systab_report_header(&efi.systab->hdr,

drivers/firmware/efi/runtime-wrappers.c+2−2

@@ -40,9 +40,9 @@ · 39 unmodified lines
40	40	* code doesn't get too cluttered:
41	41	*/
42	42	#define efi_call_virt(f, args...) \
43		− efi_call_virt_pointer(efi.systab->runtime, f, args)
	43	+ efi_call_virt_pointer(efi.runtime, f, args)
44	44	#define __efi_call_virt(f, args...) \
45		− __efi_call_virt_pointer(efi.systab->runtime, f, args)
	45	+ __efi_call_virt_pointer(efi.runtime, f, args)
46	46
47	47	struct efi_runtime_work efi_rts_work;
48	48

include/linux/efi.h+1−0

@@ -529,6 +529,7 @@ typedef struct { · 528 unmodified lines
529	529	* All runtime access to EFI goes through this structure:
530	530	*/
531	531	extern struct efi {
	532	+ const efi_runtime_services_t runtime; / EFI runtime services table */
532	533	efi_system_table_t systab; / EFI system table */
533	534	unsigned int runtime_version; /* Runtime services version */
534	535	unsigned long acpi; /* ACPI table (IA64 ext 0.71) */