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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 829eec266a..a3fc1f0ca7 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 d557098898..f6a0619743 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 b30641c805..fc496fa671 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 17199fb14a..a71f69e929 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 48dade4642..9fc4ddd3cb 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 b2bca598b9..7f69804edc 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-pink 1.4.1 (git 2.36.1) at 2024-07-31 23:28:27 +0000