Thread (77 messages) 77 messages, 2 authors, 2013-02-14

[PATCH 13/17] powerpc: Add new transactional memory state to the signal context

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STALE4995d

From: Michael Neuling <hidden>
Date: 2013-02-13 04:31:31
Subsystem: linux for powerpc (32-bit and 64-bit), the rest · Maintainers: Madhavan Srinivasan, Linus Torvalds

Revision v1 of 4 in this series.

Revisions (4)
  1. v1
  2. v1
  3. v1 current
  4. v1
This adds the new transactional memory archtected state to the signal context
in both 32 and 64 bit.

Signed-off-by: Matt Evans <redacted>
Signed-off-by: Michael Neuling <redacted>
---
 arch/powerpc/include/asm/reg.h  |    1 +
 arch/powerpc/kernel/signal.h    |    8 +
 arch/powerpc/kernel/signal_32.c |  500 ++++++++++++++++++++++++++++++++++++++-
 arch/powerpc/kernel/signal_64.c |  337 +++++++++++++++++++++++++-
 4 files changed, 830 insertions(+), 16 deletions(-)
diff --git a/arch/powerpc/include/asm/reg.h b/arch/powerpc/include/asm/reg.h
index eee2a60..7035e60 100644
--- a/arch/powerpc/include/asm/reg.h
+++ b/arch/powerpc/include/asm/reg.h
@@ -120,6 +120,7 @@
 #define TM_CAUSE_FAC_UNAV	0xfa
 #define TM_CAUSE_SYSCALL	0xf9 /* Persistent */
 #define TM_CAUSE_MISC		0xf6
+#define TM_CAUSE_SIGNAL		0xf4
 
 #if defined(CONFIG_PPC_BOOK3S_64)
 #define MSR_64BIT	MSR_SF
diff --git a/arch/powerpc/kernel/signal.h b/arch/powerpc/kernel/signal.h
index e00acb4..ec84c90 100644
--- a/arch/powerpc/kernel/signal.h
+++ b/arch/powerpc/kernel/signal.h
@@ -25,13 +25,21 @@ extern int handle_rt_signal32(unsigned long sig, struct k_sigaction *ka,
 
 extern unsigned long copy_fpr_to_user(void __user *to,
 				      struct task_struct *task);
+extern unsigned long copy_transact_fpr_to_user(void __user *to,
+					       struct task_struct *task);
 extern unsigned long copy_fpr_from_user(struct task_struct *task,
 					void __user *from);
+extern unsigned long copy_transact_fpr_from_user(struct task_struct *task,
+						 void __user *from);
 #ifdef CONFIG_VSX
 extern unsigned long copy_vsx_to_user(void __user *to,
 				      struct task_struct *task);
+extern unsigned long copy_transact_vsx_to_user(void __user *to,
+					       struct task_struct *task);
 extern unsigned long copy_vsx_from_user(struct task_struct *task,
 					void __user *from);
+extern unsigned long copy_transact_vsx_from_user(struct task_struct *task,
+						 void __user *from);
 #endif
 
 #ifdef CONFIG_PPC64
diff --git a/arch/powerpc/kernel/signal_32.c b/arch/powerpc/kernel/signal_32.c
index 804e323..e4a88d3 100644
--- a/arch/powerpc/kernel/signal_32.c
+++ b/arch/powerpc/kernel/signal_32.c
@@ -43,6 +43,7 @@
 #include <asm/sigcontext.h>
 #include <asm/vdso.h>
 #include <asm/switch_to.h>
+#include <asm/tm.h>
 #ifdef CONFIG_PPC64
 #include "ppc32.h"
 #include <asm/unistd.h>
@@ -293,6 +294,10 @@ long sys_sigaction(int sig, struct old_sigaction __user *act,
 struct sigframe {
 	struct sigcontext sctx;		/* the sigcontext */
 	struct mcontext	mctx;		/* all the register values */
+#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
+	struct sigcontext sctx_transact;
+	struct mcontext	mctx_transact;
+#endif
 	/*
 	 * Programs using the rs6000/xcoff abi can save up to 19 gp
 	 * regs and 18 fp regs below sp before decrementing it.
@@ -321,6 +326,9 @@ struct rt_sigframe {
 	struct siginfo info;
 #endif
 	struct ucontext	uc;
+#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
+	struct ucontext	uc_transact;
+#endif
 	/*
 	 * Programs using the rs6000/xcoff abi can save up to 19 gp
 	 * regs and 18 fp regs below sp before decrementing it.
@@ -381,6 +389,61 @@ unsigned long copy_vsx_from_user(struct task_struct *task,
 		task->thread.fpr[i][TS_VSRLOWOFFSET] = buf[i];
 	return 0;
 }
+
+#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
+unsigned long copy_transact_fpr_to_user(void __user *to,
+				  struct task_struct *task)
+{
+	double buf[ELF_NFPREG];
+	int i;
+
+	/* save FPR copy to local buffer then write to the thread_struct */
+	for (i = 0; i < (ELF_NFPREG - 1) ; i++)
+		buf[i] = task->thread.TS_TRANS_FPR(i);
+	memcpy(&buf[i], &task->thread.transact_fpscr, sizeof(double));
+	return __copy_to_user(to, buf, ELF_NFPREG * sizeof(double));
+}
+
+unsigned long copy_transact_fpr_from_user(struct task_struct *task,
+					  void __user *from)
+{
+	double buf[ELF_NFPREG];
+	int i;
+
+	if (__copy_from_user(buf, from, ELF_NFPREG * sizeof(double)))
+		return 1;
+	for (i = 0; i < (ELF_NFPREG - 1) ; i++)
+		task->thread.TS_TRANS_FPR(i) = buf[i];
+	memcpy(&task->thread.transact_fpscr, &buf[i], sizeof(double));
+
+	return 0;
+}
+
+unsigned long copy_transact_vsx_to_user(void __user *to,
+				  struct task_struct *task)
+{
+	double buf[ELF_NVSRHALFREG];
+	int i;
+
+	/* save FPR copy to local buffer then write to the thread_struct */
+	for (i = 0; i < ELF_NVSRHALFREG; i++)
+		buf[i] = task->thread.transact_fpr[i][TS_VSRLOWOFFSET];
+	return __copy_to_user(to, buf, ELF_NVSRHALFREG * sizeof(double));
+}
+
+unsigned long copy_transact_vsx_from_user(struct task_struct *task,
+					  void __user *from)
+{
+	double buf[ELF_NVSRHALFREG];
+	int i;
+
+	if (__copy_from_user(buf, from, ELF_NVSRHALFREG * sizeof(double)))
+		return 1;
+	for (i = 0; i < ELF_NVSRHALFREG ; i++)
+		task->thread.transact_fpr[i][TS_VSRLOWOFFSET] = buf[i];
+	return 0;
+}
+#endif /* CONFIG_PPC_TRANSACTIONAL_MEM */
 #else
 inline unsigned long copy_fpr_to_user(void __user *to,
 				      struct task_struct *task)
@@ -395,6 +458,22 @@ inline unsigned long copy_fpr_from_user(struct task_struct *task,
 	return __copy_from_user(task->thread.fpr, from,
 			      ELF_NFPREG * sizeof(double));
 }
+
+#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
+inline unsigned long copy_transact_fpr_to_user(void __user *to,
+					 struct task_struct *task)
+{
+	return __copy_to_user(to, task->thread.transact_fpr,
+			      ELF_NFPREG * sizeof(double));
+}
+
+inline unsigned long copy_transact_fpr_from_user(struct task_struct *task,
+						 void __user *from)
+{
+	return __copy_from_user(task->thread.transact_fpr, from,
+				ELF_NFPREG * sizeof(double));
+}
+#endif /* CONFIG_PPC_TRANSACTIONAL_MEM */
 #endif
 
 /*
@@ -483,6 +562,156 @@ static int save_user_regs(struct pt_regs *regs, struct mcontext __user *frame,
 	return 0;
 }
 
+#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
+/*
+ * Save the current user registers on the user stack.
+ * We only save the altivec/spe registers if the process has used
+ * altivec/spe instructions at some point.
+ * We also save the transactional registers to a second ucontext in the
+ * frame.
+ *
+ * See save_user_regs() and signal_64.c:setup_tm_sigcontexts().
+ */
+static int save_tm_user_regs(struct pt_regs *regs,
+			     struct mcontext __user *frame,
+			     struct mcontext __user *tm_frame, int sigret)
+{
+	unsigned long msr = regs->msr;
+
+	/* tm_reclaim rolls back all reg states, updating thread.ckpt_regs,
+	 * thread.transact_fpr[], thread.transact_vr[], etc.
+	 */
+	tm_enable();
+	tm_reclaim(&current->thread, msr, TM_CAUSE_SIGNAL);
+
+	/* Make sure floating point registers are stored in regs */
+	flush_fp_to_thread(current);
+
+	/* Save both sets of general registers */
+	if (save_general_regs(&current->thread.ckpt_regs, frame)
+	    || save_general_regs(regs, tm_frame))
+		return 1;
+
+	/* Stash the top half of the 64bit MSR into the 32bit MSR word
+	 * of the transactional mcontext.  This way we have a backward-compatible
+	 * MSR in the 'normal' (checkpointed) mcontext and additionally one can
+	 * also look at what type of transaction (T or S) was active at the
+	 * time of the signal.
+	 */
+	if (__put_user((msr >> 32), &tm_frame->mc_gregs[PT_MSR]))
+		return 1;
+
+#ifdef CONFIG_ALTIVEC
+	/* save altivec registers */
+	if (current->thread.used_vr) {
+		flush_altivec_to_thread(current);
+		if (__copy_to_user(&frame->mc_vregs, current->thread.vr,
+				   ELF_NVRREG * sizeof(vector128)))
+			return 1;
+		if (msr & MSR_VEC) {
+			if (__copy_to_user(&tm_frame->mc_vregs,
+					   current->thread.transact_vr,
+					   ELF_NVRREG * sizeof(vector128)))
+				return 1;
+		} else {
+			if (__copy_to_user(&tm_frame->mc_vregs,
+					   current->thread.vr,
+					   ELF_NVRREG * sizeof(vector128)))
+				return 1;
+		}
+
+		/* set MSR_VEC in the saved MSR value to indicate that
+		 * frame->mc_vregs contains valid data
+		 */
+		msr |= MSR_VEC;
+	}
+
+	/* We always copy to/from vrsave, it's 0 if we don't have or don't
+	 * use altivec. Since VSCR only contains 32 bits saved in the least
+	 * significant bits of a vector, we "cheat" and stuff VRSAVE in the
+	 * most significant bits of that same vector. --BenH
+	 */
+	if (__put_user(current->thread.vrsave,
+		       (u32 __user *)&frame->mc_vregs[32]))
+		return 1;
+	if (msr & MSR_VEC) {
+		if (__put_user(current->thread.transact_vrsave,
+			       (u32 __user *)&tm_frame->mc_vregs[32]))
+			return 1;
+	} else {
+		if (__put_user(current->thread.vrsave,
+			       (u32 __user *)&tm_frame->mc_vregs[32]))
+			return 1;
+	}
+#endif /* CONFIG_ALTIVEC */
+
+	if (copy_fpr_to_user(&frame->mc_fregs, current))
+		return 1;
+	if (msr & MSR_FP) {
+		if (copy_transact_fpr_to_user(&tm_frame->mc_fregs, current))
+			return 1;
+	} else {
+		if (copy_fpr_to_user(&tm_frame->mc_fregs, current))
+			return 1;
+	}
+
+#ifdef CONFIG_VSX
+	/*
+	 * Copy VSR 0-31 upper half from thread_struct to local
+	 * buffer, then write that to userspace.  Also set MSR_VSX in
+	 * the saved MSR value to indicate that frame->mc_vregs
+	 * contains valid data
+	 */
+	if (current->thread.used_vsr) {
+		__giveup_vsx(current);
+		if (copy_vsx_to_user(&frame->mc_vsregs, current))
+			return 1;
+		if (msr & MSR_VSX) {
+			if (copy_transact_vsx_to_user(&tm_frame->mc_vsregs,
+						      current))
+				return 1;
+		} else {
+			if (copy_vsx_to_user(&tm_frame->mc_vsregs, current))
+				return 1;
+		}
+
+		msr |= MSR_VSX;
+	}
+#endif /* CONFIG_VSX */
+#ifdef CONFIG_SPE
+	/* SPE regs are not checkpointed with TM, so this section is
+	 * simply the same as in save_user_regs().
+	 */
+	if (current->thread.used_spe) {
+		flush_spe_to_thread(current);
+		if (__copy_to_user(&frame->mc_vregs, current->thread.evr,
+				   ELF_NEVRREG * sizeof(u32)))
+			return 1;
+		/* set MSR_SPE in the saved MSR value to indicate that
+		 * frame->mc_vregs contains valid data */
+		msr |= MSR_SPE;
+	}
+
+	/* We always copy to/from spefscr */
+	if (__put_user(current->thread.spefscr, (u32 __user *)&frame->mc_vregs + ELF_NEVRREG))
+		return 1;
+#endif /* CONFIG_SPE */
+
+	if (__put_user(msr, &frame->mc_gregs[PT_MSR]))
+		return 1;
+	if (sigret) {
+		/* Set up the sigreturn trampoline: li r0,sigret; sc */
+		if (__put_user(0x38000000UL + sigret, &frame->tramp[0])
+		    || __put_user(0x44000002UL, &frame->tramp[1]))
+			return 1;
+		flush_icache_range((unsigned long) &frame->tramp[0],
+				   (unsigned long) &frame->tramp[2]);
+	}
+
+	return 0;
+}
+#endif
+
 /*
  * Restore the current user register values from the user stack,
  * (except for MSR).
@@ -588,6 +817,139 @@ static long restore_user_regs(struct pt_regs *regs,
 	return 0;
 }
 
+#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
+/*
+ * Restore the current user register values from the user stack, except for
+ * MSR, and recheckpoint the original checkpointed register state for processes
+ * in transactions.
+ */
+static long restore_tm_user_regs(struct pt_regs *regs,
+				 struct mcontext __user *sr,
+				 struct mcontext __user *tm_sr)
+{
+	long err;
+	unsigned long msr;
+#ifdef CONFIG_VSX
+	int i;
+#endif
+
+	/*
+	 * restore general registers but not including MSR or SOFTE. Also
+	 * take care of keeping r2 (TLS) intact if not a signal.
+	 * See comment in signal_64.c:restore_tm_sigcontexts();
+	 * TFHAR is restored from the checkpointed NIP; TEXASR and TFIAR
+	 * were set by the signal delivery.
+	 */
+	err = restore_general_regs(regs, tm_sr);
+	err |= restore_general_regs(&current->thread.ckpt_regs, sr);
+
+	err |= __get_user(current->thread.tm_tfhar, &sr->mc_gregs[PT_NIP]);
+
+	err |= __get_user(msr, &sr->mc_gregs[PT_MSR]);
+	if (err)
+		return 1;
+
+	/* Restore the previous little-endian mode */
+	regs->msr = (regs->msr & ~MSR_LE) | (msr & MSR_LE);
+
+	/*
+	 * Do this before updating the thread state in
+	 * current->thread.fpr/vr/evr.  That way, if we get preempted
+	 * and another task grabs the FPU/Altivec/SPE, it won't be
+	 * tempted to save the current CPU state into the thread_struct
+	 * and corrupt what we are writing there.
+	 */
+	discard_lazy_cpu_state();
+
+#ifdef CONFIG_ALTIVEC
+	regs->msr &= ~MSR_VEC;
+	if (msr & MSR_VEC) {
+		/* restore altivec registers from the stack */
+		if (__copy_from_user(current->thread.vr, &sr->mc_vregs,
+				     sizeof(sr->mc_vregs)) ||
+		    __copy_from_user(current->thread.transact_vr,
+				     &tm_sr->mc_vregs,
+				     sizeof(sr->mc_vregs)))
+			return 1;
+	} else if (current->thread.used_vr) {
+		memset(current->thread.vr, 0, ELF_NVRREG * sizeof(vector128));
+		memset(current->thread.transact_vr, 0,
+		       ELF_NVRREG * sizeof(vector128));
+	}
+
+	/* Always get VRSAVE back */
+	if (__get_user(current->thread.vrsave,
+		       (u32 __user *)&sr->mc_vregs[32]) ||
+	    __get_user(current->thread.transact_vrsave,
+		       (u32 __user *)&tm_sr->mc_vregs[32]))
+		return 1;
+#endif /* CONFIG_ALTIVEC */
+
+	regs->msr &= ~(MSR_FP | MSR_FE0 | MSR_FE1);
+
+	if (copy_fpr_from_user(current, &sr->mc_fregs) ||
+	    copy_transact_fpr_from_user(current, &tm_sr->mc_fregs))
+		return 1;
+
+#ifdef CONFIG_VSX
+	regs->msr &= ~MSR_VSX;
+	if (msr & MSR_VSX) {
+		/*
+		 * Restore altivec registers from the stack to a local
+		 * buffer, then write this out to the thread_struct
+		 */
+		if (copy_vsx_from_user(current, &sr->mc_vsregs) ||
+		    copy_transact_vsx_from_user(current, &tm_sr->mc_vsregs))
+			return 1;
+	} else if (current->thread.used_vsr)
+		for (i = 0; i < 32 ; i++) {
+			current->thread.fpr[i][TS_VSRLOWOFFSET] = 0;
+			current->thread.transact_fpr[i][TS_VSRLOWOFFSET] = 0;
+		}
+#endif /* CONFIG_VSX */
+
+#ifdef CONFIG_SPE
+	/* SPE regs are not checkpointed with TM, so this section is
+	 * simply the same as in restore_user_regs().
+	 */
+	regs->msr &= ~MSR_SPE;
+	if (msr & MSR_SPE) {
+		if (__copy_from_user(current->thread.evr, &sr->mc_vregs,
+				     ELF_NEVRREG * sizeof(u32)))
+			return 1;
+	} else if (current->thread.used_spe)
+		memset(current->thread.evr, 0, ELF_NEVRREG * sizeof(u32));
+
+	/* Always get SPEFSCR back */
+	if (__get_user(current->thread.spefscr, (u32 __user *)&sr->mc_vregs
+		       + ELF_NEVRREG))
+		return 1;
+#endif /* CONFIG_SPE */
+
+	/* Now, recheckpoint.  This loads up all of the checkpointed (older)
+	 * registers, including FP and V[S]Rs.  After recheckpointing, the
+	 * transactional versions should be loaded.
+	 */
+	tm_enable();
+	/* This loads the checkpointed FP/VEC state, if used */
+	tm_recheckpoint(&current->thread, msr);
+	/* The task has moved into TM state S, so ensure MSR reflects this */
+	regs->msr = (regs->msr & ~MSR_TS_MASK) | MSR_TS_S;
+
+	/* This loads the speculative FP/VEC state, if used */
+	if (msr & MSR_FP) {
+		do_load_up_transact_fpu(&current->thread);
+		regs->msr |= (MSR_FP | current->thread.fpexc_mode);
+	}
+	if (msr & MSR_VEC) {
+		do_load_up_transact_altivec(&current->thread);
+		regs->msr |= MSR_VEC;
+	}
+
+	return 0;
+}
+#endif
+
 #ifdef CONFIG_PPC64
 long compat_sys_rt_sigaction(int sig, const struct sigaction32 __user *act,
 		struct sigaction32 __user *oact, size_t sigsetsize)
@@ -827,6 +1189,8 @@ int handle_rt_signal32(unsigned long sig, struct k_sigaction *ka,
 	struct mcontext __user *frame;
 	void __user *addr;
 	unsigned long newsp = 0;
+	int sigret;
+	unsigned long tramp;
 
 	/* Set up Signal Frame */
 	/* Put a Real Time Context onto stack */
@@ -838,7 +1202,6 @@ int handle_rt_signal32(unsigned long sig, struct k_sigaction *ka,
 	/* Put the siginfo & fill in most of the ucontext */
 	if (copy_siginfo_to_user(&rt_sf->info, info)
 	    || __put_user(0, &rt_sf->uc.uc_flags)
-	    || __put_user(0, &rt_sf->uc.uc_link)
 	    || __put_user(current->sas_ss_sp, &rt_sf->uc.uc_stack.ss_sp)
 	    || __put_user(sas_ss_flags(regs->gpr[1]),
 			  &rt_sf->uc.uc_stack.ss_flags)
@@ -852,14 +1215,37 @@ int handle_rt_signal32(unsigned long sig, struct k_sigaction *ka,
 	frame = &rt_sf->uc.uc_mcontext;
 	addr = frame;
 	if (vdso32_rt_sigtramp && current->mm->context.vdso_base) {
-		if (save_user_regs(regs, frame, 0, 1))
-			goto badframe;
-		regs->link = current->mm->context.vdso_base + vdso32_rt_sigtramp;
+		sigret = 0;
+		tramp = current->mm->context.vdso_base + vdso32_rt_sigtramp;
 	} else {
-		if (save_user_regs(regs, frame, __NR_rt_sigreturn, 1))
+		sigret = __NR_rt_sigreturn;
+		tramp = (unsigned long) frame->tramp;
+	}
+
+#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
+	if (MSR_TM_ACTIVE(regs->msr)) {
+		if (save_tm_user_regs(regs, &rt_sf->uc.uc_mcontext,
+				      &rt_sf->uc_transact.uc_mcontext, sigret))
 			goto badframe;
-		regs->link = (unsigned long) frame->tramp;
 	}
+	else
+#endif
+		if (save_user_regs(regs, frame, sigret, 1))
+			goto badframe;
+	regs->link = tramp;
+
+#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
+	if (MSR_TM_ACTIVE(regs->msr)) {
+		if (__put_user((unsigned long)&rt_sf->uc_transact,
+			       &rt_sf->uc.uc_link)
+		    || __put_user(to_user_ptr(&rt_sf->uc_transact.uc_mcontext),
+				  &rt_sf->uc_transact.uc_regs))
+			goto badframe;
+	}
+	else
+#endif
+		if (__put_user(0, &rt_sf->uc.uc_link))
+			goto badframe;
 
 	current->thread.fpscr.val = 0;	/* turn off all fp exceptions */
 
@@ -878,6 +1264,13 @@ int handle_rt_signal32(unsigned long sig, struct k_sigaction *ka,
 	regs->nip = (unsigned long) ka->sa.sa_handler;
 	/* enter the signal handler in big-endian mode */
 	regs->msr &= ~MSR_LE;
+#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
+	/* Remove TM bits from thread's MSR.  The MSR in the sigcontext
+	 * just indicates to userland that we were doing a transaction, but we
+	 * don't want to return in transactional state:
+	 */
+	regs->msr &= ~MSR_TS_MASK;
+#endif
 	return 1;
 
 badframe:
@@ -925,6 +1318,35 @@ static int do_setcontext(struct ucontext __user *ucp, struct pt_regs *regs, int
 	return 0;
 }
 
+#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
+static int do_setcontext_tm(struct ucontext __user *ucp,
+			    struct ucontext __user *tm_ucp,
+			    struct pt_regs *regs)
+{
+	sigset_t set;
+	struct mcontext __user *mcp;
+	struct mcontext __user *tm_mcp;
+	u32 cmcp;
+	u32 tm_cmcp;
+
+	if (get_sigset_t(&set, &ucp->uc_sigmask))
+		return -EFAULT;
+
+	if (__get_user(cmcp, &ucp->uc_regs) ||
+	    __get_user(tm_cmcp, &tm_ucp->uc_regs))
+		return -EFAULT;
+	mcp = (struct mcontext __user *)(u64)cmcp;
+	tm_mcp = (struct mcontext __user *)(u64)tm_cmcp;
+	/* no need to check access_ok(mcp), since mcp < 4GB */
+
+	set_current_blocked(&set);
+	if (restore_tm_user_regs(regs, mcp, tm_mcp))
+		return -EFAULT;
+
+	return 0;
+}
+#endif
+
 long sys_swapcontext(struct ucontext __user *old_ctx,
 		     struct ucontext __user *new_ctx,
 		     int ctx_size, int r6, int r7, int r8, struct pt_regs *regs)
@@ -1020,7 +1442,12 @@ long sys_rt_sigreturn(int r3, int r4, int r5, int r6, int r7, int r8,
 		     struct pt_regs *regs)
 {
 	struct rt_sigframe __user *rt_sf;
-
+#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
+	struct ucontext __user *uc_transact;
+	unsigned long msr_hi;
+	unsigned long tmp;
+	int tm_restore = 0;
+#endif
 	/* Always make any pending restarted system calls return -EINTR */
 	current_thread_info()->restart_block.fn = do_no_restart_syscall;
 
@@ -1028,6 +1455,34 @@ long sys_rt_sigreturn(int r3, int r4, int r5, int r6, int r7, int r8,
 		(regs->gpr[1] + __SIGNAL_FRAMESIZE + 16);
 	if (!access_ok(VERIFY_READ, rt_sf, sizeof(*rt_sf)))
 		goto bad;
+#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
+	if (__get_user(tmp, &rt_sf->uc.uc_link))
+		goto bad;
+	uc_transact = (struct ucontext __user *)(uintptr_t)tmp;
+	if (uc_transact) {
+		u32 cmcp;
+		struct mcontext __user *mcp;
+
+		if (__get_user(cmcp, &uc_transact->uc_regs))
+			return -EFAULT;
+		mcp = (struct mcontext __user *)(u64)cmcp;
+		/* The top 32 bits of the MSR are stashed in the transactional
+		 * ucontext. */
+		if (__get_user(msr_hi, &mcp->mc_gregs[PT_MSR]))
+			goto bad;
+
+		if (MSR_TM_SUSPENDED(msr_hi<<32)) {
+			/* We only recheckpoint on return if we're
+			 * transaction.
+			 */
+			tm_restore = 1;
+			if (do_setcontext_tm(&rt_sf->uc, uc_transact, regs))
+				goto bad;
+		}
+	}
+	if (!tm_restore)
+		/* Fall through, for non-TM restore */
+#endif
 	if (do_setcontext(&rt_sf->uc, regs, 1))
 		goto bad;
 
@@ -1179,6 +1634,8 @@ int handle_signal32(unsigned long sig, struct k_sigaction *ka,
 	struct sigcontext __user *sc;
 	struct sigframe __user *frame;
 	unsigned long newsp = 0;
+	int sigret;
+	unsigned long tramp;
 
 	/* Set up Signal Frame */
 	frame = get_sigframe(ka, regs, sizeof(*frame), 1);
@@ -1201,14 +1658,25 @@ int handle_signal32(unsigned long sig, struct k_sigaction *ka,
 		goto badframe;
 
 	if (vdso32_sigtramp && current->mm->context.vdso_base) {
-		if (save_user_regs(regs, &frame->mctx, 0, 1))
-			goto badframe;
-		regs->link = current->mm->context.vdso_base + vdso32_sigtramp;
+		sigret = 0;
+		tramp = current->mm->context.vdso_base + vdso32_sigtramp;
 	} else {
-		if (save_user_regs(regs, &frame->mctx, __NR_sigreturn, 1))
+		sigret = __NR_sigreturn;
+		tramp = (unsigned long) frame->mctx.tramp;
+	}
+
+#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
+	if (MSR_TM_ACTIVE(regs->msr)) {
+		if (save_tm_user_regs(regs, &frame->mctx, &frame->mctx_transact,
+				      sigret))
 			goto badframe;
-		regs->link = (unsigned long) frame->mctx.tramp;
 	}
+	else
+#endif
+		if (save_user_regs(regs, &frame->mctx, sigret, 1))
+			goto badframe;
+
+	regs->link = tramp;
 
 	current->thread.fpscr.val = 0;	/* turn off all fp exceptions */
 
@@ -1223,7 +1691,13 @@ int handle_signal32(unsigned long sig, struct k_sigaction *ka,
 	regs->nip = (unsigned long) ka->sa.sa_handler;
 	/* enter the signal handler in big-endian mode */
 	regs->msr &= ~MSR_LE;
-
+#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
+	/* Remove TM bits from thread's MSR.  The MSR in the sigcontext
+	 * just indicates to userland that we were doing a transaction, but we
+	 * don't want to return in transactional state:
+	 */
+	regs->msr &= ~MSR_TS_MASK;
+#endif
 	return 1;
 
 badframe:
diff --git a/arch/powerpc/kernel/signal_64.c b/arch/powerpc/kernel/signal_64.c
index 1ca045d..7a76ee4 100644
--- a/arch/powerpc/kernel/signal_64.c
+++ b/arch/powerpc/kernel/signal_64.c
@@ -34,6 +34,7 @@
 #include <asm/syscalls.h>
 #include <asm/vdso.h>
 #include <asm/switch_to.h>
+#include <asm/tm.h>
 
 #include "signal.h"
 
@@ -56,6 +57,9 @@
 struct rt_sigframe {
 	/* sys_rt_sigreturn requires the ucontext be the first field */
 	struct ucontext uc;
+#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
+	struct ucontext uc_transact;
+#endif
 	unsigned long _unused[2];
 	unsigned int tramp[TRAMP_SIZE];
 	struct siginfo __user *pinfo;
@@ -145,6 +149,145 @@ static long setup_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs,
 	return err;
 }
 
+#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
+/*
+ * As above, but Transactional Memory is in use, so deliver sigcontexts
+ * containing checkpointed and transactional register states.
+ *
+ * To do this, we treclaim to gather both sets of registers and set up the
+ * 'normal' sigcontext registers with rolled-back register values such that a
+ * simple signal handler sees a correct checkpointed register state.
+ * If interested, a TM-aware sighandler can examine the transactional registers
+ * in the 2nd sigcontext to determine the real origin of the signal.
+ */
+static long setup_tm_sigcontexts(struct sigcontext __user *sc,
+				 struct sigcontext __user *tm_sc,
+				 struct pt_regs *regs,
+				 int signr, sigset_t *set, unsigned long handler)
+{
+	/* When CONFIG_ALTIVEC is set, we _always_ setup v_regs even if the
+	 * process never used altivec yet (MSR_VEC is zero in pt_regs of
+	 * the context). This is very important because we must ensure we
+	 * don't lose the VRSAVE content that may have been set prior to
+	 * the process doing its first vector operation
+	 * Userland shall check AT_HWCAP to know wether it can rely on the
+	 * v_regs pointer or not.
+	 */
+#ifdef CONFIG_ALTIVEC
+	elf_vrreg_t __user *v_regs = (elf_vrreg_t __user *)
+		(((unsigned long)sc->vmx_reserve + 15) & ~0xful);
+	elf_vrreg_t __user *tm_v_regs = (elf_vrreg_t __user *)
+		(((unsigned long)tm_sc->vmx_reserve + 15) & ~0xful);
+#endif
+	unsigned long msr = regs->msr;
+	long err = 0;
+
+	BUG_ON(!MSR_TM_ACTIVE(regs->msr));
+
+	/* tm_reclaim rolls back all reg states, saving checkpointed (older)
+	 * GPRs to thread.ckpt_regs and (if used) FPRs to (newer)
+	 * thread.transact_fp and/or VRs to (newer) thread.transact_vr.
+	 * THEN we save out FP/VRs, if necessary, to the checkpointed (older)
+	 * thread.fr[]/vr[]s.  The transactional (newer) GPRs are on the
+	 * stack, in *regs.
+	 */
+	tm_enable();
+	tm_reclaim(&current->thread, msr, TM_CAUSE_SIGNAL);
+
+	flush_fp_to_thread(current);
+
+#ifdef CONFIG_ALTIVEC
+	err |= __put_user(v_regs, &sc->v_regs);
+	err |= __put_user(tm_v_regs, &tm_sc->v_regs);
+
+	/* save altivec registers */
+	if (current->thread.used_vr) {
+		flush_altivec_to_thread(current);
+		/* Copy 33 vec registers (vr0..31 and vscr) to the stack */
+		err |= __copy_to_user(v_regs, current->thread.vr,
+				      33 * sizeof(vector128));
+		/* If VEC was enabled there are transactional VRs valid too,
+		 * else they're a copy of the checkpointed VRs.
+		 */
+		if (msr & MSR_VEC)
+			err |= __copy_to_user(tm_v_regs,
+					      current->thread.transact_vr,
+					      33 * sizeof(vector128));
+		else
+			err |= __copy_to_user(tm_v_regs,
+					      current->thread.vr,
+					      33 * sizeof(vector128));
+
+		/* set MSR_VEC in the MSR value in the frame to indicate
+		 * that sc->v_reg contains valid data.
+		 */
+		msr |= MSR_VEC;
+	}
+	/* We always copy to/from vrsave, it's 0 if we don't have or don't
+	 * use altivec.
+	 */
+	err |= __put_user(current->thread.vrsave, (u32 __user *)&v_regs[33]);
+	if (msr & MSR_VEC)
+		err |= __put_user(current->thread.transact_vrsave,
+				  (u32 __user *)&tm_v_regs[33]);
+	else
+		err |= __put_user(current->thread.vrsave,
+				  (u32 __user *)&tm_v_regs[33]);
+
+#else /* CONFIG_ALTIVEC */
+	err |= __put_user(0, &sc->v_regs);
+	err |= __put_user(0, &tm_sc->v_regs);
+#endif /* CONFIG_ALTIVEC */
+
+	/* copy fpr regs and fpscr */
+	err |= copy_fpr_to_user(&sc->fp_regs, current);
+	if (msr & MSR_FP)
+		err |= copy_transact_fpr_to_user(&tm_sc->fp_regs, current);
+	else
+		err |= copy_fpr_to_user(&tm_sc->fp_regs, current);
+
+#ifdef CONFIG_VSX
+	/*
+	 * Copy VSX low doubleword to local buffer for formatting,
+	 * then out to userspace.  Update v_regs to point after the
+	 * VMX data.
+	 */
+	if (current->thread.used_vsr) {
+		__giveup_vsx(current);
+		v_regs += ELF_NVRREG;
+		tm_v_regs += ELF_NVRREG;
+
+		err |= copy_vsx_to_user(v_regs, current);
+
+		if (msr & MSR_VSX)
+			err |= copy_transact_vsx_to_user(tm_v_regs, current);
+		else
+			err |= copy_vsx_to_user(tm_v_regs, current);
+
+		/* set MSR_VSX in the MSR value in the frame to
+		 * indicate that sc->vs_reg) contains valid data.
+		 */
+		msr |= MSR_VSX;
+	}
+#endif /* CONFIG_VSX */
+
+	err |= __put_user(&sc->gp_regs, &sc->regs);
+	err |= __put_user(&tm_sc->gp_regs, &tm_sc->regs);
+	WARN_ON(!FULL_REGS(regs));
+	err |= __copy_to_user(&tm_sc->gp_regs, regs, GP_REGS_SIZE);
+	err |= __copy_to_user(&sc->gp_regs,
+			      &current->thread.ckpt_regs, GP_REGS_SIZE);
+	err |= __put_user(msr, &tm_sc->gp_regs[PT_MSR]);
+	err |= __put_user(msr, &sc->gp_regs[PT_MSR]);
+	err |= __put_user(signr, &sc->signal);
+	err |= __put_user(handler, &sc->handler);
+	if (set != NULL)
+		err |=  __put_user(set->sig[0], &sc->oldmask);
+
+	return err;
+}
+#endif
+
 /*
  * Restore the sigcontext from the signal frame.
  */
@@ -241,6 +384,153 @@ static long restore_sigcontext(struct pt_regs *regs, sigset_t *set, int sig,
 	return err;
 }
 
+#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
+/*
+ * Restore the two sigcontexts from the frame of a transactional processes.
+ */
+
+static long restore_tm_sigcontexts(struct pt_regs *regs,
+				   struct sigcontext __user *sc,
+				   struct sigcontext __user *tm_sc)
+{
+#ifdef CONFIG_ALTIVEC
+	elf_vrreg_t __user *v_regs, *tm_v_regs;
+#endif
+	unsigned long err = 0;
+	unsigned long msr;
+#ifdef CONFIG_VSX
+	int i;
+#endif
+	/* copy the GPRs */
+	err |= __copy_from_user(regs->gpr, tm_sc->gp_regs, sizeof(regs->gpr));
+	err |= __copy_from_user(&current->thread.ckpt_regs, sc->gp_regs,
+				sizeof(regs->gpr));
+
+	/*
+	 * TFHAR is restored from the checkpointed 'wound-back' ucontext's NIP.
+	 * TEXASR was set by the signal delivery reclaim, as was TFIAR.
+	 * Users doing anything abhorrent like thread-switching w/ signals for
+	 * TM-Suspended code will have to back TEXASR/TFIAR up themselves.
+	 * For the case of getting a signal and simply returning from it,
+	 * we don't need to re-copy them here.
+	 */
+	err |= __get_user(regs->nip, &tm_sc->gp_regs[PT_NIP]);
+	err |= __get_user(current->thread.tm_tfhar, &sc->gp_regs[PT_NIP]);
+
+	/* get MSR separately, transfer the LE bit if doing signal return */
+	err |= __get_user(msr, &sc->gp_regs[PT_MSR]);
+	regs->msr = (regs->msr & ~MSR_LE) | (msr & MSR_LE);
+
+	/* The following non-GPR non-FPR non-VR state is also checkpointed: */
+	err |= __get_user(regs->ctr, &tm_sc->gp_regs[PT_CTR]);
+	err |= __get_user(regs->link, &tm_sc->gp_regs[PT_LNK]);
+	err |= __get_user(regs->xer, &tm_sc->gp_regs[PT_XER]);
+	err |= __get_user(regs->ccr, &tm_sc->gp_regs[PT_CCR]);
+	err |= __get_user(current->thread.ckpt_regs.ctr,
+			  &sc->gp_regs[PT_CTR]);
+	err |= __get_user(current->thread.ckpt_regs.link,
+			  &sc->gp_regs[PT_LNK]);
+	err |= __get_user(current->thread.ckpt_regs.xer,
+			  &sc->gp_regs[PT_XER]);
+	err |= __get_user(current->thread.ckpt_regs.ccr,
+			  &sc->gp_regs[PT_CCR]);
+
+	/* These regs are not checkpointed; they can go in 'regs'. */
+	err |= __get_user(regs->trap, &sc->gp_regs[PT_TRAP]);
+	err |= __get_user(regs->dar, &sc->gp_regs[PT_DAR]);
+	err |= __get_user(regs->dsisr, &sc->gp_regs[PT_DSISR]);
+	err |= __get_user(regs->result, &sc->gp_regs[PT_RESULT]);
+
+	/*
+	 * Do this before updating the thread state in
+	 * current->thread.fpr/vr.  That way, if we get preempted
+	 * and another task grabs the FPU/Altivec, it won't be
+	 * tempted to save the current CPU state into the thread_struct
+	 * and corrupt what we are writing there.
+	 */
+	discard_lazy_cpu_state();
+
+	/*
+	 * Force reload of FP/VEC.
+	 * This has to be done before copying stuff into current->thread.fpr/vr
+	 * for the reasons explained in the previous comment.
+	 */
+	regs->msr &= ~(MSR_FP | MSR_FE0 | MSR_FE1 | MSR_VEC | MSR_VSX);
+
+#ifdef CONFIG_ALTIVEC
+	err |= __get_user(v_regs, &sc->v_regs);
+	err |= __get_user(tm_v_regs, &tm_sc->v_regs);
+	if (err)
+		return err;
+	if (v_regs && !access_ok(VERIFY_READ, v_regs, 34 * sizeof(vector128)))
+		return -EFAULT;
+	if (tm_v_regs && !access_ok(VERIFY_READ,
+				    tm_v_regs, 34 * sizeof(vector128)))
+		return -EFAULT;
+	/* Copy 33 vec registers (vr0..31 and vscr) from the stack */
+	if (v_regs != 0 && tm_v_regs != 0 && (msr & MSR_VEC) != 0) {
+		err |= __copy_from_user(current->thread.vr, v_regs,
+					33 * sizeof(vector128));
+		err |= __copy_from_user(current->thread.transact_vr, tm_v_regs,
+					33 * sizeof(vector128));
+	}
+	else if (current->thread.used_vr) {
+		memset(current->thread.vr, 0, 33 * sizeof(vector128));
+		memset(current->thread.transact_vr, 0, 33 * sizeof(vector128));
+	}
+	/* Always get VRSAVE back */
+	if (v_regs != 0 && tm_v_regs != 0) {
+		err |= __get_user(current->thread.vrsave,
+				  (u32 __user *)&v_regs[33]);
+		err |= __get_user(current->thread.transact_vrsave,
+				  (u32 __user *)&tm_v_regs[33]);
+	}
+	else {
+		current->thread.vrsave = 0;
+		current->thread.transact_vrsave = 0;
+	}
+#endif /* CONFIG_ALTIVEC */
+	/* restore floating point */
+	err |= copy_fpr_from_user(current, &sc->fp_regs);
+	err |= copy_transact_fpr_from_user(current, &tm_sc->fp_regs);
+#ifdef CONFIG_VSX
+	/*
+	 * Get additional VSX data. Update v_regs to point after the
+	 * VMX data.  Copy VSX low doubleword from userspace to local
+	 * buffer for formatting, then into the taskstruct.
+	 */
+	if (v_regs && ((msr & MSR_VSX) != 0)) {
+		v_regs += ELF_NVRREG;
+		tm_v_regs += ELF_NVRREG;
+		err |= copy_vsx_from_user(current, v_regs);
+		err |= copy_transact_vsx_from_user(current, tm_v_regs);
+	} else {
+		for (i = 0; i < 32 ; i++) {
+			current->thread.fpr[i][TS_VSRLOWOFFSET] = 0;
+			current->thread.transact_fpr[i][TS_VSRLOWOFFSET] = 0;
+		}
+	}
+#endif
+	tm_enable();
+	/* This loads the checkpointed FP/VEC state, if used */
+	tm_recheckpoint(&current->thread, msr);
+	/* The task has moved into TM state S, so ensure MSR reflects this: */
+	regs->msr = (regs->msr & ~MSR_TS_MASK) | __MASK(33);
+
+	/* This loads the speculative FP/VEC state, if used */
+	if (msr & MSR_FP) {
+		do_load_up_transact_fpu(&current->thread);
+		regs->msr |= (MSR_FP | current->thread.fpexc_mode);
+	}
+	if (msr & MSR_VEC) {
+		do_load_up_transact_altivec(&current->thread);
+		regs->msr |= MSR_VEC;
+	}
+
+	return err;
+}
+#endif
+
 /*
  * Setup the trampoline code on the stack
  */
@@ -355,6 +645,9 @@ int sys_rt_sigreturn(unsigned long r3, unsigned long r4, unsigned long r5,
 {
 	struct ucontext __user *uc = (struct ucontext __user *)regs->gpr[1];
 	sigset_t set;
+#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
+	unsigned long msr;
+#endif
 
 	/* Always make any pending restarted system calls return -EINTR */
 	current_thread_info()->restart_block.fn = do_no_restart_syscall;
@@ -365,6 +658,21 @@ int sys_rt_sigreturn(unsigned long r3, unsigned long r4, unsigned long r5,
 	if (__copy_from_user(&set, &uc->uc_sigmask, sizeof(set)))
 		goto badframe;
 	set_current_blocked(&set);
+#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
+	if (__get_user(msr, &uc->uc_mcontext.gp_regs[PT_MSR]))
+		goto badframe;
+	if (MSR_TM_SUSPENDED(msr)) {
+		/* We recheckpoint on return. */
+		struct ucontext __user *uc_transact;
+		if (__get_user(uc_transact, &uc->uc_link))
+			goto badframe;
+		if (restore_tm_sigcontexts(regs, &uc->uc_mcontext,
+					   &uc_transact->uc_mcontext))
+			goto badframe;
+	}
+	else
+	/* Fall through, for non-TM restore */
+#endif
 	if (restore_sigcontext(regs, NULL, 1, &uc->uc_mcontext))
 		goto badframe;
 
@@ -415,19 +723,42 @@ int handle_rt_signal64(int signr, struct k_sigaction *ka, siginfo_t *info,
 
 	/* Create the ucontext.  */
 	err |= __put_user(0, &frame->uc.uc_flags);
-	err |= __put_user(0, &frame->uc.uc_link);
 	err |= __put_user(current->sas_ss_sp, &frame->uc.uc_stack.ss_sp);
 	err |= __put_user(sas_ss_flags(regs->gpr[1]),
 			  &frame->uc.uc_stack.ss_flags);
 	err |= __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size);
-	err |= setup_sigcontext(&frame->uc.uc_mcontext, regs, signr, NULL,
-				(unsigned long)ka->sa.sa_handler, 1);
+#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
+	if (MSR_TM_ACTIVE(regs->msr)) {
+		/* The ucontext_t passed to userland points to the second
+		 * ucontext_t (for transactional state) with its uc_link ptr.
+		 */
+		err |= __put_user(&frame->uc_transact, &frame->uc.uc_link);
+		err |= setup_tm_sigcontexts(&frame->uc.uc_mcontext,
+					    &frame->uc_transact.uc_mcontext,
+					    regs, signr,
+					    NULL,
+					    (unsigned long)ka->sa.sa_handler);
+	} else
+#endif
+	{
+		err |= __put_user(0, &frame->uc.uc_link);
+		err |= setup_sigcontext(&frame->uc.uc_mcontext, regs, signr,
+					NULL, (unsigned long)ka->sa.sa_handler,
+					1);
+	}
 	err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
 	if (err)
 		goto badframe;
 
 	/* Make sure signal handler doesn't get spurious FP exceptions */
 	current->thread.fpscr.val = 0;
+#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
+	/* Remove TM bits from thread's MSR.  The MSR in the sigcontext
+	 * just indicates to userland that we were doing a transaction, but we
+	 * don't want to return in transactional state:
+	 */
+	regs->msr &= ~MSR_TS_MASK;
+#endif
 
 	/* Set up to return from userspace. */
 	if (vdso64_rt_sigtramp && current->mm->context.vdso_base) {
-- 
1.7.10.4
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