[PATCH v9 20/28] x86/asm: Make some functions local

From: Jiri Slaby
Date: Fri Oct 11 2019 - 07:52:18 EST


There is a couple of assembly functions, which are invoked only locally
in the file they are defined. In C, they are marked "static". In
assembly, annotate them using SYM_{FUNC,CODE}_START_LOCAL (and switch
their ENDPROC to SYM_{FUNC,CODE}_END too). Whether FUNC or CODE is used,
depends on whether ENDPROC or END was used for a particular function
before.

Signed-off-by: Jiri Slaby <jslaby@xxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxxxx>
Cc: "H. Peter Anvin" <hpa@xxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: x86@xxxxxxxxxx
Cc: Matt Fleming <matt@xxxxxxxxxxxxxxxxxxx>
Cc: Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx>
Cc: linux-efi@xxxxxxxxxxxxxxx
Cc: xen-devel@xxxxxxxxxxxxxxxxxxxx
---
arch/x86/boot/compressed/efi_thunk_64.S | 8 ++++----
arch/x86/entry/entry_64.S | 21 +++++++++++----------
arch/x86/lib/copy_page_64.S | 4 ++--
arch/x86/lib/memcpy_64.S | 12 ++++++------
arch/x86/lib/memset_64.S | 8 ++++----
arch/x86/platform/efi/efi_thunk_64.S | 12 ++++++------
arch/x86/platform/pvh/head.S | 4 ++--
7 files changed, 35 insertions(+), 34 deletions(-)

diff --git a/arch/x86/boot/compressed/efi_thunk_64.S b/arch/x86/boot/compressed/efi_thunk_64.S
index d66000d23921..31312070db22 100644
--- a/arch/x86/boot/compressed/efi_thunk_64.S
+++ b/arch/x86/boot/compressed/efi_thunk_64.S
@@ -99,12 +99,12 @@ ENTRY(efi64_thunk)
ret
ENDPROC(efi64_thunk)

-ENTRY(efi_exit32)
+SYM_FUNC_START_LOCAL(efi_exit32)
movq func_rt_ptr(%rip), %rax
push %rax
mov %rdi, %rax
ret
-ENDPROC(efi_exit32)
+SYM_FUNC_END(efi_exit32)

.code32
/*
@@ -112,7 +112,7 @@ ENDPROC(efi_exit32)
*
* The stack should represent the 32-bit calling convention.
*/
-ENTRY(efi_enter32)
+SYM_FUNC_START_LOCAL(efi_enter32)
movl $__KERNEL_DS, %eax
movl %eax, %ds
movl %eax, %es
@@ -172,7 +172,7 @@ ENTRY(efi_enter32)
btsl $X86_CR0_PG_BIT, %eax
movl %eax, %cr0
lret
-ENDPROC(efi_enter32)
+SYM_FUNC_END(efi_enter32)

.data
.balign 8
diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S
index 57d246048ac6..1568da63bf16 100644
--- a/arch/x86/entry/entry_64.S
+++ b/arch/x86/entry/entry_64.S
@@ -1101,7 +1101,8 @@ idtentry hypervisor_callback xen_do_hypervisor_callback has_error_code=0
* existing activation in its critical region -- if so, we pop the current
* activation and restart the handler using the previous one.
*/
-ENTRY(xen_do_hypervisor_callback) /* do_hypervisor_callback(struct *pt_regs) */
+/* do_hypervisor_callback(struct *pt_regs) */
+SYM_CODE_START_LOCAL(xen_do_hypervisor_callback)

/*
* Since we don't modify %rdi, evtchn_do_upall(struct *pt_regs) will
@@ -1119,7 +1120,7 @@ ENTRY(xen_do_hypervisor_callback) /* do_hypervisor_callback(struct *pt_regs) */
call xen_maybe_preempt_hcall
#endif
jmp error_exit
-END(xen_do_hypervisor_callback)
+SYM_CODE_END(xen_do_hypervisor_callback)

/*
* Hypervisor uses this for application faults while it executes.
@@ -1214,7 +1215,7 @@ idtentry machine_check do_mce has_error_code=0 paranoid=1
* Use slow, but surefire "are we in kernel?" check.
* Return: ebx=0: need swapgs on exit, ebx=1: otherwise
*/
-ENTRY(paranoid_entry)
+SYM_CODE_START_LOCAL(paranoid_entry)
UNWIND_HINT_FUNC
cld
PUSH_AND_CLEAR_REGS save_ret=1
@@ -1248,7 +1249,7 @@ ENTRY(paranoid_entry)
FENCE_SWAPGS_KERNEL_ENTRY

ret
-END(paranoid_entry)
+SYM_CODE_END(paranoid_entry)

/*
* "Paranoid" exit path from exception stack. This is invoked
@@ -1262,7 +1263,7 @@ END(paranoid_entry)
*
* On entry, ebx is "no swapgs" flag (1: don't need swapgs, 0: need it)
*/
-ENTRY(paranoid_exit)
+SYM_CODE_START_LOCAL(paranoid_exit)
UNWIND_HINT_REGS
DISABLE_INTERRUPTS(CLBR_ANY)
TRACE_IRQS_OFF_DEBUG
@@ -1279,12 +1280,12 @@ ENTRY(paranoid_exit)
RESTORE_CR3 scratch_reg=%rbx save_reg=%r14
.Lparanoid_exit_restore:
jmp restore_regs_and_return_to_kernel
-END(paranoid_exit)
+SYM_CODE_END(paranoid_exit)

/*
* Save all registers in pt_regs, and switch GS if needed.
*/
-ENTRY(error_entry)
+SYM_CODE_START_LOCAL(error_entry)
UNWIND_HINT_FUNC
cld
PUSH_AND_CLEAR_REGS save_ret=1
@@ -1364,16 +1365,16 @@ ENTRY(error_entry)
call fixup_bad_iret
mov %rax, %rsp
jmp .Lerror_entry_from_usermode_after_swapgs
-END(error_entry)
+SYM_CODE_END(error_entry)

-ENTRY(error_exit)
+SYM_CODE_START_LOCAL(error_exit)
UNWIND_HINT_REGS
DISABLE_INTERRUPTS(CLBR_ANY)
TRACE_IRQS_OFF
testb $3, CS(%rsp)
jz retint_kernel
jmp .Lretint_user
-END(error_exit)
+SYM_CODE_END(error_exit)

/*
* Runs on exception stack. Xen PV does not go through this path at all,
diff --git a/arch/x86/lib/copy_page_64.S b/arch/x86/lib/copy_page_64.S
index fd2d09afa097..f505870bd93b 100644
--- a/arch/x86/lib/copy_page_64.S
+++ b/arch/x86/lib/copy_page_64.S
@@ -21,7 +21,7 @@ ENTRY(copy_page)
ENDPROC(copy_page)
EXPORT_SYMBOL(copy_page)

-ENTRY(copy_page_regs)
+SYM_FUNC_START_LOCAL(copy_page_regs)
subq $2*8, %rsp
movq %rbx, (%rsp)
movq %r12, 1*8(%rsp)
@@ -86,4 +86,4 @@ ENTRY(copy_page_regs)
movq 1*8(%rsp), %r12
addq $2*8, %rsp
ret
-ENDPROC(copy_page_regs)
+SYM_FUNC_END(copy_page_regs)
diff --git a/arch/x86/lib/memcpy_64.S b/arch/x86/lib/memcpy_64.S
index 57a64266ba69..3265b21e86c0 100644
--- a/arch/x86/lib/memcpy_64.S
+++ b/arch/x86/lib/memcpy_64.S
@@ -29,7 +29,7 @@
* rax original destination
*/
SYM_FUNC_START_ALIAS(__memcpy)
-ENTRY(memcpy)
+SYM_FUNC_START_LOCAL(memcpy)
ALTERNATIVE_2 "jmp memcpy_orig", "", X86_FEATURE_REP_GOOD, \
"jmp memcpy_erms", X86_FEATURE_ERMS

@@ -41,7 +41,7 @@ ENTRY(memcpy)
movl %edx, %ecx
rep movsb
ret
-ENDPROC(memcpy)
+SYM_FUNC_END(memcpy)
SYM_FUNC_END_ALIAS(__memcpy)
EXPORT_SYMBOL(memcpy)
EXPORT_SYMBOL(__memcpy)
@@ -50,14 +50,14 @@ EXPORT_SYMBOL(__memcpy)
* memcpy_erms() - enhanced fast string memcpy. This is faster and
* simpler than memcpy. Use memcpy_erms when possible.
*/
-ENTRY(memcpy_erms)
+SYM_FUNC_START_LOCAL(memcpy_erms)
movq %rdi, %rax
movq %rdx, %rcx
rep movsb
ret
-ENDPROC(memcpy_erms)
+SYM_FUNC_END(memcpy_erms)

-ENTRY(memcpy_orig)
+SYM_FUNC_START_LOCAL(memcpy_orig)
movq %rdi, %rax

cmpq $0x20, %rdx
@@ -182,7 +182,7 @@ ENTRY(memcpy_orig)

.Lend:
retq
-ENDPROC(memcpy_orig)
+SYM_FUNC_END(memcpy_orig)

#ifndef CONFIG_UML

diff --git a/arch/x86/lib/memset_64.S b/arch/x86/lib/memset_64.S
index 927ac44d34aa..564abf9ecedb 100644
--- a/arch/x86/lib/memset_64.S
+++ b/arch/x86/lib/memset_64.S
@@ -59,16 +59,16 @@ EXPORT_SYMBOL(__memset)
*
* rax original destination
*/
-ENTRY(memset_erms)
+SYM_FUNC_START_LOCAL(memset_erms)
movq %rdi,%r9
movb %sil,%al
movq %rdx,%rcx
rep stosb
movq %r9,%rax
ret
-ENDPROC(memset_erms)
+SYM_FUNC_END(memset_erms)

-ENTRY(memset_orig)
+SYM_FUNC_START_LOCAL(memset_orig)
movq %rdi,%r10

/* expand byte value */
@@ -139,4 +139,4 @@ ENTRY(memset_orig)
subq %r8,%rdx
jmp .Lafter_bad_alignment
.Lfinal:
-ENDPROC(memset_orig)
+SYM_FUNC_END(memset_orig)
diff --git a/arch/x86/platform/efi/efi_thunk_64.S b/arch/x86/platform/efi/efi_thunk_64.S
index 46c58b08739c..d677a7eb2d0a 100644
--- a/arch/x86/platform/efi/efi_thunk_64.S
+++ b/arch/x86/platform/efi/efi_thunk_64.S
@@ -67,7 +67,7 @@ ENDPROC(efi64_thunk)
*
* This function must be invoked with a 1:1 mapped stack.
*/
-ENTRY(__efi64_thunk)
+SYM_FUNC_START_LOCAL(__efi64_thunk)
movl %ds, %eax
push %rax
movl %es, %eax
@@ -114,14 +114,14 @@ ENTRY(__efi64_thunk)
or %rcx, %rax
1:
ret
-ENDPROC(__efi64_thunk)
+SYM_FUNC_END(__efi64_thunk)

-ENTRY(efi_exit32)
+SYM_FUNC_START_LOCAL(efi_exit32)
movq func_rt_ptr(%rip), %rax
push %rax
mov %rdi, %rax
ret
-ENDPROC(efi_exit32)
+SYM_FUNC_END(efi_exit32)

.code32
/*
@@ -129,7 +129,7 @@ ENDPROC(efi_exit32)
*
* The stack should represent the 32-bit calling convention.
*/
-ENTRY(efi_enter32)
+SYM_FUNC_START_LOCAL(efi_enter32)
movl $__KERNEL_DS, %eax
movl %eax, %ds
movl %eax, %es
@@ -145,7 +145,7 @@ ENTRY(efi_enter32)
pushl %eax

lret
-ENDPROC(efi_enter32)
+SYM_FUNC_END(efi_enter32)

.data
.balign 8
diff --git a/arch/x86/platform/pvh/head.S b/arch/x86/platform/pvh/head.S
index 4e63480bb223..43b4d864817e 100644
--- a/arch/x86/platform/pvh/head.S
+++ b/arch/x86/platform/pvh/head.S
@@ -50,7 +50,7 @@
#define PVH_DS_SEL (PVH_GDT_ENTRY_DS * 8)
#define PVH_CANARY_SEL (PVH_GDT_ENTRY_CANARY * 8)

-ENTRY(pvh_start_xen)
+SYM_CODE_START_LOCAL(pvh_start_xen)
cld

lgdt (_pa(gdt))
@@ -146,7 +146,7 @@ ENTRY(pvh_start_xen)

ljmp $PVH_CS_SEL, $_pa(startup_32)
#endif
-END(pvh_start_xen)
+SYM_CODE_END(pvh_start_xen)

.section ".init.data","aw"
.balign 8
--
2.23.0