[PATCH 13/17] powerpc: Add new transactional memory state to the signal context
Michael Neuling
mikey at neuling.org
Wed Feb 13 15:31:31 EST 2013
This adds the new transactional memory archtected state to the signal context
in both 32 and 64 bit.
Signed-off-by: Matt Evans <matt at ozlabs.org>
Signed-off-by: Michael Neuling <mikey at neuling.org>
---
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(¤t->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(¤t->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(¤t->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(¤t->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(¤t->thread);
+ regs->msr |= (MSR_FP | current->thread.fpexc_mode);
+ }
+ if (msr & MSR_VEC) {
+ do_load_up_transact_altivec(¤t->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(¤t->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,
+ ¤t->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(¤t->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(¤t->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(¤t->thread);
+ regs->msr |= (MSR_FP | current->thread.fpexc_mode);
+ }
+ if (msr & MSR_VEC) {
+ do_load_up_transact_altivec(¤t->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
More information about the Linuxppc-dev
mailing list