Commit 3d1228ea authored by Catalin Marinas's avatar Catalin Marinas Committed by Russell King
Browse files

[ARM] 5387/1: Add ptrace VFP support on ARM 



This patch adds ptrace support for setting and getting the VFP registers
using PTRACE_SETVFPREGS and PTRACE_GETVFPREGS. The user_vfp structure
defined in asm/user.h contains 32 double registers (to cover VFPv3 and
Neon hardware) and the FPSCR register.

Cc: Paul Brook <paul@codesourcery.com>
Cc: Daniel Jacobowitz <dan@codesourcery.com>
Signed-off-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
Signed-off-by: default avatarRussell King <rmk+kernel@arm.linux.org.uk>
parent f373e8c0

arch/arm/include/asm/ptrace.h

+2 −0
Original line number Diff line number Diff line
@@ -27,6 +27,8 @@ 
/* PTRACE_SYSCALL is 24 */

#define PTRACE_GETCRUNCHREGS	25

#define PTRACE_SETCRUNCHREGS	26

#define PTRACE_GETVFPREGS	27

#define PTRACE_SETVFPREGS	28



/*

 * PSR bits

arch/arm/include/asm/thread_info.h

+2 −0
Original line number Diff line number Diff line
@@ -113,6 +113,8 @@ extern void iwmmxt_task_restore(struct thread_info *, void *); 
extern void iwmmxt_task_release(struct thread_info *);

extern void iwmmxt_task_switch(struct thread_info *);



extern void vfp_sync_state(struct thread_info *thread);



#endif



/*

arch/arm/include/asm/user.h

+9 −0
Original line number Diff line number Diff line
@@ -81,4 +81,13 @@ struct user{ 
#define HOST_TEXT_START_ADDR (u.start_code)

#define HOST_STACK_END_ADDR (u.start_stack + u.u_ssize * NBPG)



/*

 * User specific VFP registers. If only VFPv2 is present, registers 16 to 31

 * are ignored by the ptrace system call.

 */

struct user_vfp {

	unsigned long long fpregs[32];

	unsigned long fpscr;

};



#endif /* _ARM_USER_H */

arch/arm/kernel/ptrace.c

+58 −0
Original line number Diff line number Diff line
@@ -653,6 +653,54 @@ static int ptrace_setcrunchregs(struct task_struct *tsk, void __user *ufp) 
}

#endif



#ifdef CONFIG_VFP

/*

 * Get the child VFP state.

 */

static int ptrace_getvfpregs(struct task_struct *tsk, void __user *data)

{

	struct thread_info *thread = task_thread_info(tsk);

	union vfp_state *vfp = &thread->vfpstate;

	struct user_vfp __user *ufp = data;



	vfp_sync_state(thread);



	/* copy the floating point registers */

	if (copy_to_user(&ufp->fpregs, &vfp->hard.fpregs,

			 sizeof(vfp->hard.fpregs)))

		return -EFAULT;



	/* copy the status and control register */

	if (put_user(vfp->hard.fpscr, &ufp->fpscr))

		return -EFAULT;



	return 0;

}



/*

 * Set the child VFP state.

 */

static int ptrace_setvfpregs(struct task_struct *tsk, void __user *data)

{

	struct thread_info *thread = task_thread_info(tsk);

	union vfp_state *vfp = &thread->vfpstate;

	struct user_vfp __user *ufp = data;



	vfp_sync_state(thread);



	/* copy the floating point registers */

	if (copy_from_user(&vfp->hard.fpregs, &ufp->fpregs,

			   sizeof(vfp->hard.fpregs)))

		return -EFAULT;



	/* copy the status and control register */

	if (get_user(vfp->hard.fpscr, &ufp->fpscr))

		return -EFAULT;



	return 0;

}

#endif



long arch_ptrace(struct task_struct *child, long request, long addr, long data)

{

	int ret;
@@ -775,6 +823,16 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data) 
			break;

#endif



#ifdef CONFIG_VFP

		case PTRACE_GETVFPREGS:

			ret = ptrace_getvfpregs(child, (void __user *)data);

			break;



		case PTRACE_SETVFPREGS:

			ret = ptrace_setvfpregs(child, (void __user *)data);

			break;

#endif



		default:

			ret = ptrace_request(child, request, addr, data);

			break;

arch/arm/vfp/vfp.h

+0 −2
Original line number Diff line number Diff line
@@ -377,6 +377,4 @@ struct op { 
	u32 flags;

};



#if defined(CONFIG_SMP) || defined(CONFIG_PM)

extern void vfp_save_state(void *location, u32 fpexc);
 
#endif

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