diff options
author | Michael Neuling <mikey@neuling.org> | 2013-02-13 16:21:41 +0000 |
---|---|---|
committer | Benjamin Herrenschmidt <benh@kernel.crashing.org> | 2013-02-15 17:02:23 +1100 |
commit | 2b0a576d15e0e14751f00f9c87e46bad27f217e7 (patch) | |
tree | bd160f2f67cbae826fe0216bb9e217d9c3a290c8 /arch/powerpc/kernel/signal_32.c | |
parent | bc2a9408fa65195288b41751016c36fd00a75a85 (diff) |
powerpc: Add new transactional memory state to the signal context
This adds the new transactional memory archtected state to the signal context
in both 32 and 64 bit.
Signed-off-by: Matt Evans <matt@ozlabs.org>
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Diffstat (limited to 'arch/powerpc/kernel/signal_32.c')
-rw-r--r-- | arch/powerpc/kernel/signal_32.c | 500 |
1 files changed, 487 insertions, 13 deletions
diff --git a/arch/powerpc/kernel/signal_32.c b/arch/powerpc/kernel/signal_32.c index 804e323c139..e4a88d340de 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: |