X-Git-Url: https://gerrit.opnfv.org/gerrit/gitweb?a=blobdiff_plain;f=kernel%2Farch%2Fpowerpc%2Fkernel%2Fentry_64.S;h=1aae3fdb0c2a5ef224f72335c46ff31e9cff72f6;hb=52f993b8e89487ec9ee15a7fb4979e0f09a45b27;hp=5e2d2645d1e00649408a4f6fe0d3a93af8507283;hpb=9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00;p=kvmfornfv.git

diff --git a/kernel/arch/powerpc/kernel/entry_64.S b/kernel/arch/powerpc/kernel/entry_64.S
index 5e2d2645d..1aae3fdb0 100644
--- a/kernel/arch/powerpc/kernel/entry_64.S
+++ b/kernel/arch/powerpc/kernel/entry_64.S
@@ -19,6 +19,7 @@
  */
 
 #include <linux/errno.h>
+#include <linux/err.h>
 #include <asm/unistd.h>
 #include <asm/processor.h>
 #include <asm/page.h>
@@ -34,6 +35,7 @@
 #include <asm/ftrace.h>
 #include <asm/hw_irq.h>
 #include <asm/context_tracking.h>
+#include <asm/tm.h>
 
 /*
  * System calls.
@@ -51,6 +53,12 @@ exception_marker:
 
 	.globl system_call_common
 system_call_common:
+#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
+BEGIN_FTR_SECTION
+	extrdi.	r10, r12, 1, (63-MSR_TS_T_LG) /* transaction active? */
+	bne	tabort_syscall
+END_FTR_SECTION_IFSET(CPU_FTR_TM)
+#endif
 	andi.	r10,r12,MSR_PR
 	mr	r10,r1
 	addi	r1,r1,-INT_FRAME_SIZE
@@ -143,8 +151,7 @@ END_FW_FTR_SECTION_IFSET(FW_FEATURE_SPLPAR)
 	CURRENT_THREAD_INFO(r11, r1)
 	ld	r10,TI_FLAGS(r11)
 	andi.	r11,r10,_TIF_SYSCALL_DOTRACE
-	bne	syscall_dotrace
-.Lsyscall_dotrace_cont:
+	bne	syscall_dotrace		/* does not return */
 	cmpldi	0,r0,NR_syscalls
 	bge-	syscall_enosys
 
@@ -200,7 +207,7 @@ system_call:			/* label this so stack traces look sane */
 #endif /* CONFIG_PPC_BOOK3E */
 
 	ld	r9,TI_FLAGS(r12)
-	li	r11,-_LAST_ERRNO
+	li	r11,-MAX_ERRNO
 	andi.	r0,r9,(_TIF_SYSCALL_DOTRACE|_TIF_SINGLESTEP|_TIF_USER_WORK_MASK|_TIF_PERSYSCALL_MASK)
 	bne-	syscall_exit_work
 	cmpld	r3,r11
@@ -238,22 +245,34 @@ syscall_dotrace:
 	bl	save_nvgprs
 	addi	r3,r1,STACK_FRAME_OVERHEAD
 	bl	do_syscall_trace_enter
+
 	/*
-	 * Restore argument registers possibly just changed.
-	 * We use the return value of do_syscall_trace_enter
-	 * for the call number to look up in the table (r0).
+	 * We use the return value of do_syscall_trace_enter() as the syscall
+	 * number. If the syscall was rejected for any reason do_syscall_trace_enter()
+	 * returns an invalid syscall number and the test below against
+	 * NR_syscalls will fail.
 	 */
 	mr	r0,r3
+
+	/* Restore argument registers just clobbered and/or possibly changed. */
 	ld	r3,GPR3(r1)
 	ld	r4,GPR4(r1)
 	ld	r5,GPR5(r1)
 	ld	r6,GPR6(r1)
 	ld	r7,GPR7(r1)
 	ld	r8,GPR8(r1)
+
+	/* Repopulate r9 and r10 for the system_call path */
 	addi	r9,r1,STACK_FRAME_OVERHEAD
 	CURRENT_THREAD_INFO(r10, r1)
 	ld	r10,TI_FLAGS(r10)
-	b	.Lsyscall_dotrace_cont
+
+	cmpldi	r0,NR_syscalls
+	blt+	system_call
+
+	/* Return code is already in r3 thanks to do_syscall_trace_enter() */
+	b	.Lsyscall_exit
+
 
 syscall_enosys:
 	li	r3,-ENOSYS
@@ -270,7 +289,7 @@ syscall_exit_work:
 	beq+	0f
 	REST_NVGPRS(r1)
 	b	2f
-0:	cmpld	r3,r11		/* r10 is -LAST_ERRNO */
+0:	cmpld	r3,r11		/* r11 is -MAX_ERRNO */
 	blt+	1f
 	andi.	r0,r9,_TIF_NOERROR
 	bne-	1f
@@ -311,6 +330,34 @@ syscall_exit_work:
 	bl	do_syscall_trace_leave
 	b	ret_from_except
 
+#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
+tabort_syscall:
+	/* Firstly we need to enable TM in the kernel */
+	mfmsr	r10
+	li	r9, 1
+	rldimi	r10, r9, MSR_TM_LG, 63-MSR_TM_LG
+	mtmsrd	r10, 0
+
+	/* tabort, this dooms the transaction, nothing else */
+	li	r9, (TM_CAUSE_SYSCALL|TM_CAUSE_PERSISTENT)
+	TABORT(R9)
+
+	/*
+	 * Return directly to userspace. We have corrupted user register state,
+	 * but userspace will never see that register state. Execution will
+	 * resume after the tbegin of the aborted transaction with the
+	 * checkpointed register state.
+	 */
+	li	r9, MSR_RI
+	andc	r10, r10, r9
+	mtmsrd	r10, 1
+	mtspr	SPRN_SRR0, r11
+	mtspr	SPRN_SRR1, r12
+
+	rfid
+	b	.	/* prevent speculative execution */
+#endif
+
 /* Save non-volatile GPRs, if not already saved. */
 _GLOBAL(save_nvgprs)
 	ld	r11,_TRAP(r1)
@@ -556,7 +603,7 @@ BEGIN_FTR_SECTION
 	ld	r0,THREAD_DSCR(r4)
 	cmpwi	r6,0
 	bne	1f
-	ld	r0,PACA_DSCR(r13)
+	ld	r0,PACA_DSCR_DEFAULT(r13)
 1:
 BEGIN_FTR_SECTION_NESTED(70)
 	mfspr	r8, SPRN_FSCR