[PATCH v12 04/30] powerpc/ptrace: Enable in transaction NT_PPC_VMX ptrace requests

wei.guo.simon at gmail.com wei.guo.simon at gmail.com
Wed Jul 27 19:26:29 AEST 2016


From: Anshuman Khandual <khandual at linux.vnet.ibm.com>

This patch enables in transaction NT_PPC_VMX ptrace requests. The
function vr_get which gets the running value of all VMX registers
and the function vr_set which sets the running value of of all VMX
registers work on the running set of VMX registers whose location
will be different if transaction is active. This patch makes these
functions adapt to situations when the transaction is active.

Cc: Benjamin Herrenschmidt <benh at kernel.crashing.org>
Cc: Paul Mackerras <paulus at samba.org>
Cc: Michael Ellerman <mpe at ellerman.id.au>
Cc: Shuah Khan <shuahkh at osg.samsung.com>
Cc: Anton Blanchard <anton at samba.org>
Cc: Cyril Bur <cyrilbur at gmail.com>
Cc: Anshuman Khandual <khandual at linux.vnet.ibm.com>
Cc: Simon Guo <wei.guo.simon at gmail.com>
Cc: Ulrich Weigand <ulrich.weigand at de.ibm.com>
Cc: Michael Neuling <mikey at neuling.org>
Cc: Andrew Morton <akpm at linux-foundation.org>
Cc: Kees Cook <keescook at chromium.org>
Cc: Rashmica Gupta <rashmicy at gmail.com>
Cc: Khem Raj <raj.khem at gmail.com>
Cc: Jessica Yu <jeyu at redhat.com>
Cc: Jiri Kosina <jkosina at suse.cz>
Cc: Miroslav Benes <mbenes at suse.cz>
Cc: Suraj Jitindar Singh <sjitindarsingh at gmail.com>
Cc: Chris Smart <chris at distroguy.com>
Cc: linuxppc-dev at lists.ozlabs.org
Cc: linux-kernel at vger.kernel.org
Cc: linux-kselftest at vger.kernel.org
Signed-off-by: Anshuman Khandual <khandual at linux.vnet.ibm.com>
---
 arch/powerpc/kernel/ptrace.c | 90 ++++++++++++++++++++++++++++++++++++++++++--
 1 file changed, 87 insertions(+), 3 deletions(-)

diff --git a/arch/powerpc/kernel/ptrace.c b/arch/powerpc/kernel/ptrace.c
index 82db082..3baa57e 100644
--- a/arch/powerpc/kernel/ptrace.c
+++ b/arch/powerpc/kernel/ptrace.c
@@ -518,10 +518,28 @@ static int vr_active(struct task_struct *target,
 	return target->thread.used_vr ? regset->n : 0;
 }
 
+/*
+ * When the transaction is active, 'transact_vr' holds the current running
+ * value of all the VMX registers and 'vr_state' holds the last checkpointed
+ * value of all the VMX registers for the current transaction to fall back
+ * on in case it aborts. When transaction is not active 'vr_state' holds
+ * the current running state of all the VMX registers. So this function which
+ * gets the current running values of all the VMX registers, needs to know
+ * whether any transaction is active or not.
+ *
+ * Userspace interface buffer layout:
+ *
+ * struct data {
+ *	vector128	vr[32];
+ *	vector128	vscr;
+ *	vector128	vrsave;
+ * };
+ */
 static int vr_get(struct task_struct *target, const struct user_regset *regset,
 		  unsigned int pos, unsigned int count,
 		  void *kbuf, void __user *ubuf)
 {
+	struct thread_vr_state *addr;
 	int ret;
 
 	flush_altivec_to_thread(target);
@@ -529,8 +547,19 @@ static int vr_get(struct task_struct *target, const struct user_regset *regset,
 	BUILD_BUG_ON(offsetof(struct thread_vr_state, vscr) !=
 		     offsetof(struct thread_vr_state, vr[32]));
 
+#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
+	if (MSR_TM_ACTIVE(target->thread.regs->msr)) {
+		flush_fp_to_thread(target);
+		flush_tmregs_to_thread(target);
+		addr = &target->thread.transact_vr;
+	} else {
+		addr = &target->thread.vr_state;
+	}
+#else
+	addr = &target->thread.vr_state;
+#endif
 	ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
-				  &target->thread.vr_state, 0,
+				  addr, 0,
 				  33 * sizeof(vector128));
 	if (!ret) {
 		/*
@@ -541,7 +570,16 @@ static int vr_get(struct task_struct *target, const struct user_regset *regset,
 			u32 word;
 		} vrsave;
 		memset(&vrsave, 0, sizeof(vrsave));
+
+#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
+		if (MSR_TM_ACTIVE(target->thread.regs->msr))
+			vrsave.word = target->thread.transact_vrsave;
+		else
+			vrsave.word = target->thread.vrsave;
+#else
 		vrsave.word = target->thread.vrsave;
+#endif
+
 		ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, &vrsave,
 					  33 * sizeof(vector128), -1);
 	}
@@ -549,10 +587,28 @@ static int vr_get(struct task_struct *target, const struct user_regset *regset,
 	return ret;
 }
 
+/*
+ * When the transaction is active, 'transact_vr' holds the current running
+ * value of all the VMX registers and 'vr_state' holds the last checkpointed
+ * value of all the VMX registers for the current transaction to fall back
+ * on in case it aborts. When transaction is not active 'vr_state' holds
+ * the current running state of all the VMX registers. So this function which
+ * sets the current running values of all the VMX registers, needs to know
+ * whether any transaction is active or not.
+ *
+ * Userspace interface buffer layout:
+ *
+ * struct data {
+ *	vector128	vr[32];
+ *	vector128	vscr;
+ *	vector128	vrsave;
+ * };
+ */
 static int vr_set(struct task_struct *target, const struct user_regset *regset,
 		  unsigned int pos, unsigned int count,
 		  const void *kbuf, const void __user *ubuf)
 {
+	struct thread_vr_state *addr;
 	int ret;
 
 	flush_altivec_to_thread(target);
@@ -560,8 +616,19 @@ static int vr_set(struct task_struct *target, const struct user_regset *regset,
 	BUILD_BUG_ON(offsetof(struct thread_vr_state, vscr) !=
 		     offsetof(struct thread_vr_state, vr[32]));
 
+#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
+	if (MSR_TM_ACTIVE(target->thread.regs->msr)) {
+		flush_fp_to_thread(target);
+		flush_tmregs_to_thread(target);
+		addr = &target->thread.transact_vr;
+	} else {
+		addr = &target->thread.vr_state;
+	}
+#else
+	addr = &target->thread.vr_state;
+#endif
 	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
-				 &target->thread.vr_state, 0,
+				 addr, 0,
 				 33 * sizeof(vector128));
 	if (!ret && count > 0) {
 		/*
@@ -572,11 +639,28 @@ static int vr_set(struct task_struct *target, const struct user_regset *regset,
 			u32 word;
 		} vrsave;
 		memset(&vrsave, 0, sizeof(vrsave));
+
+#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
+		if (MSR_TM_ACTIVE(target->thread.regs->msr))
+			vrsave.word = target->thread.transact_vrsave;
+		else
+			vrsave.word = target->thread.vrsave;
+#else
 		vrsave.word = target->thread.vrsave;
+#endif
 		ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &vrsave,
 					 33 * sizeof(vector128), -1);
-		if (!ret)
+		if (!ret) {
+
+#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
+			if (MSR_TM_ACTIVE(target->thread.regs->msr))
+				target->thread.transact_vrsave = vrsave.word;
+			else
+				target->thread.vrsave = vrsave.word;
+#else
 			target->thread.vrsave = vrsave.word;
+#endif
+		}
 	}
 
 	return ret;
-- 
1.8.3.1



More information about the Linuxppc-dev mailing list