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-rw-r--r--sysdeps/powerpc/powerpc32/sysdep.h15
-rw-r--r--sysdeps/powerpc/powerpc64/sysdep.h120
-rw-r--r--sysdeps/unix/sysv/linux/powerpc/powerpc64/clone.S9
-rw-r--r--sysdeps/unix/sysv/linux/powerpc/powerpc64/vfork.S6
-rw-r--r--sysdeps/unix/sysv/linux/powerpc/syscall.S11
-rw-r--r--sysdeps/unix/sysv/linux/powerpc/sysdep.h93
6 files changed, 214 insertions, 40 deletions
diff --git a/sysdeps/powerpc/powerpc32/sysdep.h b/sysdeps/powerpc/powerpc32/sysdep.h
index 829eec2..a3fc1f0 100644
--- a/sysdeps/powerpc/powerpc32/sysdep.h
+++ b/sysdeps/powerpc/powerpc32/sysdep.h
@@ -92,7 +92,10 @@ GOT_LABEL: ; \
#define DO_CALL(syscall) \
li 0,syscall; \
- sc
+ DO_CALL_SC
+
+#define DO_CALL_SC \
+ sc
#undef JUMPTARGET
#ifdef PIC
@@ -106,14 +109,20 @@ GOT_LABEL: ; \
# define HIDDEN_JUMPTARGET(name) __GI_##name##@local
#endif
+#define TAIL_CALL_SYSCALL_ERROR \
+ b __syscall_error@local
+
#define PSEUDO(name, syscall_name, args) \
.section ".text"; \
ENTRY (name) \
DO_CALL (SYS_ify (syscall_name));
+#define RET_SC \
+ bnslr+;
+
#define PSEUDO_RET \
- bnslr+; \
- b __syscall_error@local
+ RET_SC; \
+ TAIL_CALL_SYSCALL_ERROR
#define ret PSEUDO_RET
#undef PSEUDO_END
diff --git a/sysdeps/powerpc/powerpc64/sysdep.h b/sysdeps/powerpc/powerpc64/sysdep.h
index d557098..f6a0619 100644
--- a/sysdeps/powerpc/powerpc64/sysdep.h
+++ b/sysdeps/powerpc/powerpc64/sysdep.h
@@ -17,6 +17,7 @@
<https://www.gnu.org/licenses/>. */
#include <sysdeps/powerpc/sysdep.h>
+#include <tls.h>
#ifdef __ASSEMBLER__
@@ -263,10 +264,80 @@ LT_LABELSUFFIX(name,_name_end): ; \
TRACEBACK_MASK(name,mask); \
END_2(name)
-#define DO_CALL(syscall) \
- li 0,syscall; \
+/* We will allocate a new frame to save LR and the non-volatile register used to
+ read the TCB when checking for scv support on syscall code. We actually just
+ need the minimum frame size plus room for 1 reg (8 bytes). But the ABI
+ mandates stack frames should be aligned at 16 Bytes, so we end up allocating
+ a bit more space then what will actually be used. */
+#define SCV_FRAME_SIZE (FRAME_MIN_SIZE+16)
+#define SCV_FRAME_NVOLREG_SAVE FRAME_MIN_SIZE
+
+/* Allocate frame and save register */
+#define NVOLREG_SAVE \
+ stdu r1,-SCV_FRAME_SIZE(r1); \
+ std r31,SCV_FRAME_NVOLREG_SAVE(r1); \
+ cfi_adjust_cfa_offset(SCV_FRAME_SIZE);
+
+/* Restore register and destroy frame */
+#define NVOLREG_RESTORE \
+ ld r31,SCV_FRAME_NVOLREG_SAVE(r1); \
+ addi r1,r1,SCV_FRAME_SIZE; \
+ cfi_adjust_cfa_offset(-SCV_FRAME_SIZE);
+
+/* Check PPC_FEATURE2_SCV bit from hwcap2 in the TCB. If it is not set, scv is
+ not available, then go to JUMPFALSE (label given by the macro's caller). We
+ save the value we read from the TCB in a non-volatile register so we can
+ reuse it later when exiting from the syscall in PSEUDO_RET. Note that for
+ the static case we need an extra check to guarantee the thread pointer has
+ already been initialized, otherwise we may try to access an invalid address
+ if a syscall is called before the TLS has been setup. */
+ .macro CHECK_SCV_SUPPORT REG JUMPFALSE
+
+#ifndef SHARED
+ /* Check if thread pointer has already been setup. */
+ cmpdi r13,0
+ beq \JUMPFALSE
+#endif
+
+ /* Read PPC_FEATURE2_SCV from TCB and store it in REG */
+ ld \REG,TCB_HWCAP(PT_THREAD_POINTER)
+ andis. \REG,\REG,PPC_FEATURE2_SCV>>16
+
+ beq \JUMPFALSE
+ .endm
+
+#if IS_IN(rtld)
+# define DO_CALL(syscall) \
+ li r0,syscall; \
+ DO_CALL_SC
+#else
+/* Before doing the syscall, check if we can use scv. scv is supported by P9
+ and later with Linux v5.9 and later. If so, use it. Otherwise, fallback to
+ sc. We use a non-volatile register to save hwcap2 from the TCB, so we need
+ to save its content beforehand. */
+# define DO_CALL(syscall) \
+ li r0,syscall; \
+ NVOLREG_SAVE; \
+ CHECK_SCV_SUPPORT r31 0f; \
+ DO_CALL_SCV; \
+ b 1f; \
+0: DO_CALL_SC; \
+1:
+#endif /* IS_IN(rtld) */
+
+/* DO_CALL_SC and DO_CALL_SCV expect the syscall number to be in r0. */
+#define DO_CALL_SC \
sc
+#define DO_CALL_SCV \
+ mflr r9; \
+ std r9,FRAME_LR_SAVE(r1); \
+ cfi_offset(lr,FRAME_LR_SAVE); \
+ scv 0; \
+ ld r9,FRAME_LR_SAVE(r1); \
+ mtlr r9; \
+ cfi_restore(lr);
+
/* ppc64 is always PIC */
#undef JUMPTARGET
#define JUMPTARGET(name) FUNC_LABEL(name)
@@ -304,9 +375,32 @@ LT_LABELSUFFIX(name,_name_end): ; \
.endif
#endif
-#define PSEUDO_RET \
- bnslr+; \
+#if IS_IN(rtld)
+# define PSEUDO_RET \
+ RET_SC; \
TAIL_CALL_SYSCALL_ERROR
+#else
+/* This should only be called after a DO_CALL. In such cases, r31 contains the
+ value of PPC_FEATURE2_SCV read from hwcap2 by CHECK_SCV_SUPPORT. If it is
+ set, we know we have entered the kernel using scv, so handle the return code
+ accordingly. */
+# define PSEUDO_RET \
+ cmpdi cr5,r31,0; \
+ NVOLREG_RESTORE; \
+ beq cr5,0f; \
+ RET_SCV; \
+ b 1f; \
+0: RET_SC; \
+1: TAIL_CALL_SYSCALL_ERROR
+#endif
+
+#define RET_SCV \
+ cmpdi r3,0; \
+ bgelr+; \
+ neg r3,r3;
+
+#define RET_SC \
+ bnslr+;
#define ret PSEUDO_RET
@@ -319,8 +413,15 @@ LT_LABELSUFFIX(name,_name_end): ; \
ENTRY (name); \
DO_CALL (SYS_ify (syscall_name))
-#define PSEUDO_RET_NOERRNO \
+#if IS_IN(rtld)
+# define PSEUDO_RET_NOERRNO \
blr
+#else
+/* This should only be called after a DO_CALL. */
+# define PSEUDO_RET_NOERRNO \
+ NVOLREG_RESTORE; \
+ blr
+#endif /* IS_IN(rtld) */
#define ret_NOERRNO PSEUDO_RET_NOERRNO
@@ -333,8 +434,15 @@ LT_LABELSUFFIX(name,_name_end): ; \
ENTRY (name); \
DO_CALL (SYS_ify (syscall_name))
-#define PSEUDO_RET_ERRVAL \
+#if IS_IN(rtld)
+# define PSEUDO_RET_ERRVAL \
+ blr
+#else
+/* This should only be called after a DO_CALL. */
+# define PSEUDO_RET_ERRVAL \
+ NVOLREG_RESTORE; \
blr
+#endif /* IS_IN(rtld) */
#define ret_ERRVAL PSEUDO_RET_ERRVAL
diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc64/clone.S b/sysdeps/unix/sysv/linux/powerpc/powerpc64/clone.S
index b30641c..fc496fa 100644
--- a/sysdeps/unix/sysv/linux/powerpc/powerpc64/clone.S
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc64/clone.S
@@ -68,7 +68,8 @@ ENTRY (__clone)
cfi_endproc
/* Do the call. */
- DO_CALL(SYS_ify(clone))
+ li r0,SYS_ify(clone)
+ DO_CALL_SC
/* Check for child process. */
cmpdi cr1,r3,0
@@ -82,7 +83,8 @@ ENTRY (__clone)
bctrl
ld r2,FRAME_TOC_SAVE(r1)
- DO_CALL(SYS_ify(exit))
+ li r0,(SYS_ify(exit))
+ DO_CALL_SC
/* We won't ever get here but provide a nop so that the linker
will insert a toc adjusting stub if necessary. */
nop
@@ -104,7 +106,8 @@ L(parent):
cfi_restore(r30)
cfi_restore(r31)
- PSEUDO_RET
+ RET_SC
+ TAIL_CALL_SYSCALL_ERROR
END (__clone)
diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc64/vfork.S b/sysdeps/unix/sysv/linux/powerpc/powerpc64/vfork.S
index 17199fb..a71f69e 100644
--- a/sysdeps/unix/sysv/linux/powerpc/powerpc64/vfork.S
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc64/vfork.S
@@ -28,9 +28,11 @@
ENTRY (__vfork)
CALL_MCOUNT 0
- DO_CALL (SYS_ify (vfork))
+ li r0,SYS_ify (vfork)
+ DO_CALL_SC
- PSEUDO_RET
+ RET_SC
+ TAIL_CALL_SYSCALL_ERROR
PSEUDO_END (__vfork)
libc_hidden_def (__vfork)
diff --git a/sysdeps/unix/sysv/linux/powerpc/syscall.S b/sysdeps/unix/sysv/linux/powerpc/syscall.S
index 48dade4..9fc4ddd 100644
--- a/sysdeps/unix/sysv/linux/powerpc/syscall.S
+++ b/sysdeps/unix/sysv/linux/powerpc/syscall.S
@@ -25,6 +25,13 @@ ENTRY (syscall)
mr r6,r7
mr r7,r8
mr r8,r9
- sc
- PSEUDO_RET
+#if !IS_IN(rtld) && (defined(__PPC64__) || defined(__powerpc64__))
+ CHECK_SCV_SUPPORT r9 0f
+ DO_CALL_SCV
+ RET_SCV
+ b 1f
+#endif
+0: DO_CALL_SC
+ RET_SC
+1: TAIL_CALL_SYSCALL_ERROR
PSEUDO_END (syscall)
diff --git a/sysdeps/unix/sysv/linux/powerpc/sysdep.h b/sysdeps/unix/sysv/linux/powerpc/sysdep.h
index b2bca59..7f69804 100644
--- a/sysdeps/unix/sysv/linux/powerpc/sysdep.h
+++ b/sysdeps/unix/sysv/linux/powerpc/sysdep.h
@@ -64,39 +64,84 @@
#define INTERNAL_VSYSCALL_CALL(funcptr, nr, args...) \
INTERNAL_VSYSCALL_CALL_TYPE(funcptr, long int, nr, args)
+#define DECLARE_REGS \
+ register long int r0 __asm__ ("r0"); \
+ register long int r3 __asm__ ("r3"); \
+ register long int r4 __asm__ ("r4"); \
+ register long int r5 __asm__ ("r5"); \
+ register long int r6 __asm__ ("r6"); \
+ register long int r7 __asm__ ("r7"); \
+ register long int r8 __asm__ ("r8");
-#undef INTERNAL_SYSCALL
-#define INTERNAL_SYSCALL_NCS(name, nr, args...) \
- ({ \
- register long int r0 __asm__ ("r0"); \
- register long int r3 __asm__ ("r3"); \
- register long int r4 __asm__ ("r4"); \
- register long int r5 __asm__ ("r5"); \
- register long int r6 __asm__ ("r6"); \
- register long int r7 __asm__ ("r7"); \
- register long int r8 __asm__ ("r8"); \
- LOADARGS_##nr (name, ##args); \
- __asm__ __volatile__ \
- ("sc\n\t" \
- "mfcr %0\n\t" \
- "0:" \
- : "=&r" (r0), \
- "=&r" (r3), "=&r" (r4), "=&r" (r5), \
- "=&r" (r6), "=&r" (r7), "=&r" (r8) \
- : ASM_INPUT_##nr \
- : "r9", "r10", "r11", "r12", \
- "cr0", "ctr", "memory"); \
- r0 & (1 << 28) ? -r3 : r3; \
+#define SYSCALL_SCV(nr) \
+ ({ \
+ __asm__ __volatile__ \
+ ("scv 0\n\t" \
+ "0:" \
+ : "=&r" (r0), \
+ "=&r" (r3), "=&r" (r4), "=&r" (r5), \
+ "=&r" (r6), "=&r" (r7), "=&r" (r8) \
+ : ASM_INPUT_##nr \
+ : "r9", "r10", "r11", "r12", \
+ "lr", "ctr", "memory"); \
+ r3; \
})
-#define INTERNAL_SYSCALL(name, nr, args...) \
- INTERNAL_SYSCALL_NCS (__NR_##name, nr, args)
+
+#define SYSCALL_SC(nr) \
+ ({ \
+ __asm__ __volatile__ \
+ ("sc\n\t" \
+ "mfcr %0\n\t" \
+ "0:" \
+ : "=&r" (r0), \
+ "=&r" (r3), "=&r" (r4), "=&r" (r5), \
+ "=&r" (r6), "=&r" (r7), "=&r" (r8) \
+ : ASM_INPUT_##nr \
+ : "r9", "r10", "r11", "r12", \
+ "cr0", "ctr", "memory"); \
+ r0 & (1 << 28) ? -r3 : r3; \
+ })
+
+/* This will only be non-empty for 64-bit systems, see below. */
+#define TRY_SYSCALL_SCV(nr)
#if defined(__PPC64__) || defined(__powerpc64__)
# define SYSCALL_ARG_SIZE 8
+
+/* For the static case, unlike the dynamic loader, there is no compile-time way
+ to check if we are inside startup code. So we need to check if the thread
+ pointer has already been setup before trying to access the TLS. */
+# ifndef SHARED
+# define CHECK_THREAD_POINTER (__thread_register != 0)
+# else
+# define CHECK_THREAD_POINTER (1)
+# endif
+
+/* When inside the dynamic loader, the thread pointer may not have been
+ initialized yet, so don't check for scv support in that case. */
+# if !IS_IN(rtld)
+# undef TRY_SYSCALL_SCV
+# define TRY_SYSCALL_SCV(nr) \
+ CHECK_THREAD_POINTER && THREAD_GET_HWCAP() & PPC_FEATURE2_SCV ? \
+ SYSCALL_SCV(nr) :
+# endif
+
#else
# define SYSCALL_ARG_SIZE 4
#endif
+# define INTERNAL_SYSCALL_NCS(name, nr, args...) \
+ ({ \
+ DECLARE_REGS; \
+ LOADARGS_##nr (name, ##args); \
+ TRY_SYSCALL_SCV(nr) \
+ SYSCALL_SC(nr); \
+ })
+
+#undef INTERNAL_SYSCALL
+#define INTERNAL_SYSCALL(name, nr, args...) \
+ INTERNAL_SYSCALL_NCS (__NR_##name, nr, args)
+
#define LOADARGS_0(name, dummy) \
r0 = name
#define LOADARGS_1(name, __arg1) \
generated by cgit v1.1 at 2024-07-25 21:18:46 +0000