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>
This commit is contained in:
Michael Neuling 2013-02-13 16:21:41 +00:00 committed by Benjamin Herrenschmidt
parent bc2a9408fa
commit 2b0a576d15
4 changed files with 832 additions and 18 deletions

View file

@ -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

View file

@ -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

View file

@ -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)
@ -852,15 +1215,38 @@ 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))
goto badframe;
regs->link = (unsigned long) frame->tramp;
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;
}
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 */
/* create a stack frame for the caller of the handler */
@ -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);
@ -1201,15 +1658,26 @@ 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))
goto badframe;
regs->link = (unsigned long) frame->mctx.tramp;
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;
}
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 */
/* create a stack frame for the caller of the handler */
@ -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:

View file

@ -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) {