From 7fec1b57b8a925d83c194f995f83d9f8442fd48e Mon Sep 17 00:00:00 2001 From: Catalin Marinas Date: Mon, 28 Nov 2011 13:53:28 +0000 Subject: ARM: Remove __ARCH_WANT_INTERRUPTS_ON_CTXSW on ASID-capable CPUs Since the ASIDs must be unique to an mm across all the CPUs in a system, the __new_context() function needs to broadcast a context reset event to all the CPUs during ASID allocation if a roll-over occurred. Such IPIs cannot be issued with interrupts disabled and ARM had to define __ARCH_WANT_INTERRUPTS_ON_CTXSW. This patch changes the check_context() function to check_and_switch_context() called from switch_mm(). In case of ASID-capable CPUs (ARMv6 onwards), if a new ASID is needed and the interrupts are disabled, it defers the __new_context() and cpu_switch_mm() calls to the post-lock switch hook where the interrupts are enabled. Setting the reserved TTBR0 was also moved to check_and_switch_context() from cpu_v7_switch_mm(). Reviewed-by: Will Deacon Tested-by: Will Deacon Reviewed-by: Frank Rowand Tested-by: Marc Zyngier Signed-off-by: Catalin Marinas --- arch/arm/include/asm/thread_info.h | 1 + 1 file changed, 1 insertion(+) (limited to 'arch/arm/include/asm/thread_info.h') diff --git a/arch/arm/include/asm/thread_info.h b/arch/arm/include/asm/thread_info.h index d4c24d412a8..9e13e33ec74 100644 --- a/arch/arm/include/asm/thread_info.h +++ b/arch/arm/include/asm/thread_info.h @@ -146,6 +146,7 @@ extern void vfp_flush_hwstate(struct thread_info *); #define TIF_MEMDIE 18 /* is terminating due to OOM killer */ #define TIF_RESTORE_SIGMASK 20 #define TIF_SECCOMP 21 +#define TIF_SWITCH_MM 22 /* deferred switch_mm */ #define _TIF_SIGPENDING (1 << TIF_SIGPENDING) #define _TIF_NEED_RESCHED (1 << TIF_NEED_RESCHED) -- cgit v1.2.3-70-g09d2 From 2498814fcb3068f19b82b1519b4038721f61af43 Mon Sep 17 00:00:00 2001 From: Will Deacon Date: Mon, 23 Apr 2012 15:38:28 +0100 Subject: ARM: 7399/1: vfp: move user vfp state save/restore code out of signal.c The user VFP state must be preserved (subject to ucontext modifications) across invocation of a signal handler and this is currently handled by vfp_{preserve,restore}_context in signal.c Since this code requires intimate low-level knowledge of the VFP state, this patch moves it into vfpmodule.c. Signed-off-by: Will Deacon Signed-off-by: Russell King --- arch/arm/include/asm/thread_info.h | 7 ++++ arch/arm/kernel/signal.c | 55 ++------------------------ arch/arm/vfp/vfpmodule.c | 79 ++++++++++++++++++++++++++++++++++++++ 3 files changed, 90 insertions(+), 51 deletions(-) (limited to 'arch/arm/include/asm/thread_info.h') diff --git a/arch/arm/include/asm/thread_info.h b/arch/arm/include/asm/thread_info.h index d4c24d412a8..0f04d84582e 100644 --- a/arch/arm/include/asm/thread_info.h +++ b/arch/arm/include/asm/thread_info.h @@ -118,6 +118,13 @@ extern void iwmmxt_task_switch(struct thread_info *); extern void vfp_sync_hwstate(struct thread_info *); extern void vfp_flush_hwstate(struct thread_info *); +struct user_vfp; +struct user_vfp_exc; + +extern int vfp_preserve_user_clear_hwstate(struct user_vfp __user *, + struct user_vfp_exc __user *); +extern int vfp_restore_user_hwstate(struct user_vfp __user *, + struct user_vfp_exc __user *); #endif /* diff --git a/arch/arm/kernel/signal.c b/arch/arm/kernel/signal.c index 7cb532fc8aa..d68d1b69468 100644 --- a/arch/arm/kernel/signal.c +++ b/arch/arm/kernel/signal.c @@ -180,44 +180,23 @@ static int restore_iwmmxt_context(struct iwmmxt_sigframe *frame) static int preserve_vfp_context(struct vfp_sigframe __user *frame) { - struct thread_info *thread = current_thread_info(); - struct vfp_hard_struct *h = &thread->vfpstate.hard; const unsigned long magic = VFP_MAGIC; const unsigned long size = VFP_STORAGE_SIZE; int err = 0; - vfp_sync_hwstate(thread); __put_user_error(magic, &frame->magic, err); __put_user_error(size, &frame->size, err); - /* - * Copy the floating point registers. There can be unused - * registers see asm/hwcap.h for details. - */ - err |= __copy_to_user(&frame->ufp.fpregs, &h->fpregs, - sizeof(h->fpregs)); - /* - * Copy the status and control register. - */ - __put_user_error(h->fpscr, &frame->ufp.fpscr, err); - - /* - * Copy the exception registers. - */ - __put_user_error(h->fpexc, &frame->ufp_exc.fpexc, err); - __put_user_error(h->fpinst, &frame->ufp_exc.fpinst, err); - __put_user_error(h->fpinst2, &frame->ufp_exc.fpinst2, err); + if (err) + return -EFAULT; - return err ? -EFAULT : 0; + return vfp_preserve_user_clear_hwstate(&frame->ufp, &frame->ufp_exc); } static int restore_vfp_context(struct vfp_sigframe __user *frame) { - struct thread_info *thread = current_thread_info(); - struct vfp_hard_struct *h = &thread->vfpstate.hard; unsigned long magic; unsigned long size; - unsigned long fpexc; int err = 0; __get_user_error(magic, &frame->magic, err); @@ -228,33 +207,7 @@ static int restore_vfp_context(struct vfp_sigframe __user *frame) if (magic != VFP_MAGIC || size != VFP_STORAGE_SIZE) return -EINVAL; - vfp_flush_hwstate(thread); - - /* - * Copy the floating point registers. There can be unused - * registers see asm/hwcap.h for details. - */ - err |= __copy_from_user(&h->fpregs, &frame->ufp.fpregs, - sizeof(h->fpregs)); - /* - * Copy the status and control register. - */ - __get_user_error(h->fpscr, &frame->ufp.fpscr, err); - - /* - * Sanitise and restore the exception registers. - */ - __get_user_error(fpexc, &frame->ufp_exc.fpexc, err); - /* Ensure the VFP is enabled. */ - fpexc |= FPEXC_EN; - /* Ensure FPINST2 is invalid and the exception flag is cleared. */ - fpexc &= ~(FPEXC_EX | FPEXC_FP2V); - h->fpexc = fpexc; - - __get_user_error(h->fpinst, &frame->ufp_exc.fpinst, err); - __get_user_error(h->fpinst2, &frame->ufp_exc.fpinst2, err); - - return err ? -EFAULT : 0; + return vfp_restore_user_hwstate(&frame->ufp, &frame->ufp_exc); } #endif diff --git a/arch/arm/vfp/vfpmodule.c b/arch/arm/vfp/vfpmodule.c index 858748eaa14..05872d92fca 100644 --- a/arch/arm/vfp/vfpmodule.c +++ b/arch/arm/vfp/vfpmodule.c @@ -17,6 +17,8 @@ #include #include #include +#include +#include #include #include @@ -528,6 +530,83 @@ void vfp_flush_hwstate(struct thread_info *thread) put_cpu(); } +/* + * Save the current VFP state into the provided structures and prepare + * for entry into a new function (signal handler). + */ +int vfp_preserve_user_clear_hwstate(struct user_vfp __user *ufp, + struct user_vfp_exc __user *ufp_exc) +{ + struct thread_info *thread = current_thread_info(); + struct vfp_hard_struct *hwstate = &thread->vfpstate.hard; + int err = 0; + + /* Ensure that the saved hwstate is up-to-date. */ + vfp_sync_hwstate(thread); + + /* + * Copy the floating point registers. There can be unused + * registers see asm/hwcap.h for details. + */ + err |= __copy_to_user(&ufp->fpregs, &hwstate->fpregs, + sizeof(hwstate->fpregs)); + /* + * Copy the status and control register. + */ + __put_user_error(hwstate->fpscr, &ufp->fpscr, err); + + /* + * Copy the exception registers. + */ + __put_user_error(hwstate->fpexc, &ufp_exc->fpexc, err); + __put_user_error(hwstate->fpinst, &ufp_exc->fpinst, err); + __put_user_error(hwstate->fpinst2, &ufp_exc->fpinst2, err); + + if (err) + return -EFAULT; + return 0; +} + +/* Sanitise and restore the current VFP state from the provided structures. */ +int vfp_restore_user_hwstate(struct user_vfp __user *ufp, + struct user_vfp_exc __user *ufp_exc) +{ + struct thread_info *thread = current_thread_info(); + struct vfp_hard_struct *hwstate = &thread->vfpstate.hard; + unsigned long fpexc; + int err = 0; + + vfp_flush_hwstate(thread); + + /* + * Copy the floating point registers. There can be unused + * registers see asm/hwcap.h for details. + */ + err |= __copy_from_user(&hwstate->fpregs, &ufp->fpregs, + sizeof(hwstate->fpregs)); + /* + * Copy the status and control register. + */ + __get_user_error(hwstate->fpscr, &ufp->fpscr, err); + + /* + * Sanitise and restore the exception registers. + */ + __get_user_error(fpexc, &ufp_exc->fpexc, err); + + /* Ensure the VFP is enabled. */ + fpexc |= FPEXC_EN; + + /* Ensure FPINST2 is invalid and the exception flag is cleared. */ + fpexc &= ~(FPEXC_EX | FPEXC_FP2V); + hwstate->fpexc = fpexc; + + __get_user_error(hwstate->fpinst, &ufp_exc->fpinst, err); + __get_user_error(hwstate->fpinst2, &ufp_exc->fpinst2, err); + + return err ? -EFAULT : 0; +} + /* * VFP hardware can lose all context when a CPU goes offline. * As we will be running in SMP mode with CPU hotplug, we will save the -- cgit v1.2.3-70-g09d2