powerpc/signal32: Isolate non-copy actions in save_user_regs() and save_tm_user_regs()

Reorder actions in save_user_regs() and save_tm_user_regs() to
regroup copies together in order to switch to user_access_begin()
logic in a later patch.

Move non-copy actions into new functions called
prepare_save_user_regs() and prepare_save_tm_user_regs().

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/f6eac65781b4a57220477c8864bca2b57f29a5d5.1597770847.git.christophe.leroy@csgroup.eu
This commit is contained in:
Christophe Leroy 2020-08-18 17:19:36 +00:00 committed by Michael Ellerman
parent b3484a1d4d
commit 968c4fccd1
1 changed files with 41 additions and 13 deletions

View File

@ -229,14 +229,31 @@ struct rt_sigframe {
* We only save the altivec/spe registers if the process has used
* altivec/spe instructions at some point.
*/
static void prepare_save_user_regs(int ctx_has_vsx_region)
{
/* Make sure floating point registers are stored in regs */
flush_fp_to_thread(current);
#ifdef CONFIG_ALTIVEC
if (current->thread.used_vr)
flush_altivec_to_thread(current);
if (cpu_has_feature(CPU_FTR_ALTIVEC))
current->thread.vrsave = mfspr(SPRN_VRSAVE);
#endif
#ifdef CONFIG_VSX
if (current->thread.used_vsr && ctx_has_vsx_region)
flush_vsx_to_thread(current);
#endif
#ifdef CONFIG_SPE
if (current->thread.used_spe)
flush_spe_to_thread(current);
#endif
}
static int save_user_regs(struct pt_regs *regs, struct mcontext __user *frame,
struct mcontext __user *tm_frame, int ctx_has_vsx_region)
{
unsigned long msr = regs->msr;
/* Make sure floating point registers are stored in regs */
flush_fp_to_thread(current);
/* save general registers */
if (save_general_regs(regs, frame))
return 1;
@ -244,7 +261,6 @@ static int save_user_regs(struct pt_regs *regs, struct mcontext __user *frame,
#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_state,
ELF_NVRREG * sizeof(vector128)))
return 1;
@ -260,8 +276,6 @@ static int save_user_regs(struct pt_regs *regs, struct mcontext __user *frame,
* most significant bits of that same vector. --BenH
* Note that the current VRSAVE value is in the SPR at this point.
*/
if (cpu_has_feature(CPU_FTR_ALTIVEC))
current->thread.vrsave = mfspr(SPRN_VRSAVE);
if (__put_user(current->thread.vrsave, (u32 __user *)&frame->mc_vregs[32]))
return 1;
#endif /* CONFIG_ALTIVEC */
@ -281,7 +295,6 @@ static int save_user_regs(struct pt_regs *regs, struct mcontext __user *frame,
* contains valid data
*/
if (current->thread.used_vsr && ctx_has_vsx_region) {
flush_vsx_to_thread(current);
if (copy_vsx_to_user(&frame->mc_vsregs, current))
return 1;
msr |= MSR_VSX;
@ -290,7 +303,6 @@ static int save_user_regs(struct pt_regs *regs, struct mcontext __user *frame,
#ifdef CONFIG_SPE
/* save spe registers */
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;
@ -326,11 +338,23 @@ static int save_user_regs(struct pt_regs *regs, struct mcontext __user *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, unsigned long msr)
static void prepare_save_tm_user_regs(void)
{
WARN_ON(tm_suspend_disabled);
#ifdef CONFIG_ALTIVEC
if (cpu_has_feature(CPU_FTR_ALTIVEC))
current->thread.ckvrsave = mfspr(SPRN_VRSAVE);
#endif
#ifdef CONFIG_SPE
if (current->thread.used_spe)
flush_spe_to_thread(current);
#endif
}
static int save_tm_user_regs(struct pt_regs *regs, struct mcontext __user *frame,
struct mcontext __user *tm_frame, unsigned long msr)
{
/* Save both sets of general registers */
if (save_general_regs(&current->thread.ckpt_regs, frame)
|| save_general_regs(regs, tm_frame))
@ -374,8 +398,6 @@ static int save_tm_user_regs(struct pt_regs *regs, struct mcontext __user *frame
* significant bits of a vector, we "cheat" and stuff VRSAVE in the
* most significant bits of that same vector. --BenH
*/
if (cpu_has_feature(CPU_FTR_ALTIVEC))
current->thread.ckvrsave = mfspr(SPRN_VRSAVE);
if (__put_user(current->thread.ckvrsave,
(u32 __user *)&frame->mc_vregs[32]))
return 1;
@ -427,7 +449,6 @@ static int save_tm_user_regs(struct pt_regs *regs, struct mcontext __user *frame
* 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;
@ -447,6 +468,8 @@ static int save_tm_user_regs(struct pt_regs *regs, struct mcontext __user *frame
return 0;
}
#else
static void prepare_save_tm_user_regs(void) { }
static int save_tm_user_regs(struct pt_regs *regs, struct mcontext __user *frame,
struct mcontext __user *tm_frame, unsigned long msr)
{
@ -790,9 +813,11 @@ int handle_rt_signal32(struct ksignal *ksig, sigset_t *oldset,
flush_icache_range(tramp, tramp + 2 * sizeof(unsigned long));
if (MSR_TM_ACTIVE(msr)) {
prepare_save_tm_user_regs();
if (save_tm_user_regs(regs, mctx, tm_mctx, msr))
goto badframe;
} else {
prepare_save_user_regs(1);
if (save_user_regs(regs, mctx, tm_mctx, 1))
goto badframe;
}
@ -881,9 +906,11 @@ int handle_signal32(struct ksignal *ksig, sigset_t *oldset,
flush_icache_range(tramp, tramp + 2 * sizeof(unsigned long));
if (MSR_TM_ACTIVE(msr)) {
prepare_save_tm_user_regs();
if (save_tm_user_regs(regs, mctx, tm_mctx, msr))
goto badframe;
} else {
prepare_save_user_regs(1);
if (save_user_regs(regs, mctx, tm_mctx, 1))
goto badframe;
}
@ -1038,6 +1065,7 @@ SYSCALL_DEFINE3(swapcontext, struct ucontext __user *, old_ctx,
*/
mctx = (struct mcontext __user *)
((unsigned long) &old_ctx->uc_mcontext & ~0xfUL);
prepare_save_user_regs(ctx_has_vsx_region);
if (save_user_regs(regs, mctx, NULL, ctx_has_vsx_region))
return -EFAULT;
if (!user_write_access_begin(old_ctx, ctx_size))