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Diffstat (limited to 'arch/powerpc/kernel/signal_64.c')
-rw-r--r--arch/powerpc/kernel/signal_64.c337
1 files changed, 334 insertions, 3 deletions
diff --git a/arch/powerpc/kernel/signal_64.c b/arch/powerpc/kernel/signal_64.c
index 1ca045d4432..7a76ee48a95 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) {