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Commit ee1e17c6 authored by Al Viro's avatar Al Viro
Browse files

blackfin: convert kernel_thread() and kernel_execve() to generic ones 



Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
parent ddffeb8c

arch/blackfin/Kconfig

+2 −0
Original line number Diff line number Diff line
@@ -45,6 +45,8 @@ config BLACKFIN 
	select ARCH_USES_GETTIMEOFFSET if !GENERIC_CLOCKEVENTS

	select HAVE_MOD_ARCH_SPECIFIC

	select MODULES_USE_ELF_RELA

	select GENERIC_KERNEL_THREAD

	select GENERIC_KERNEL_EXECVE



config GENERIC_CSUM

	def_bool y

arch/blackfin/include/asm/processor.h

+0 −2
Original line number Diff line number Diff line
@@ -75,8 +75,6 @@ static inline void release_thread(struct task_struct *dead_task) 
{

}



extern int kernel_thread(int (*fn) (void *), void *arg, unsigned long flags);



/*

 * Free current thread data structures etc..

 */

arch/blackfin/kernel/entry.S

+8 −14
Original line number Diff line number Diff line
@@ -46,22 +46,16 @@ ENTRY(_ret_from_fork) 
	SP += -12;

	pseudo_long_call _schedule_tail, p5;

	SP += 12;

	r0 = [sp + PT_IPEND];

	cc = bittst(r0,1);

	if cc jump .Lin_kernel;

	p1 = [sp++];

	r0 = [sp++];

	cc = p1 == 0;

	if cc jump .Lfork;

	sp += -12;

	call (p1);

	sp += 12;

.Lfork:

	RESTORE_CONTEXT

	rti;

.Lin_kernel:

	bitclr(r0,1);

	[sp + PT_IPEND] = r0;

	/* do a 'fake' RTI by jumping to [RETI]

	 * to avoid clearing supervisor mode in child

	 */

	r0 = [sp + PT_PC];

	[sp + PT_P0] = r0;



	RESTORE_ALL_SYS

	jump (p0);

ENDPROC(_ret_from_fork)



ENTRY(_sys_vfork)

arch/blackfin/kernel/process.c

+17 −38
Original line number Diff line number Diff line
@@ -101,40 +101,6 @@ void cpu_idle(void) 
	}

}



/*

 * This gets run with P1 containing the

 * function to call, and R1 containing

 * the "args".  Note P0 is clobbered on the way here.

 */

void kernel_thread_helper(void);

__asm__(".section .text\n"

	".align 4\n"

	"_kernel_thread_helper:\n\t"

	"\tsp += -12;\n\t"

	"\tr0 = r1;\n\t" "\tcall (p1);\n\t" "\tcall _do_exit;\n" ".previous");



/*

 * Create a kernel thread.

 */

pid_t kernel_thread(int (*fn) (void *), void *arg, unsigned long flags)

{

	struct pt_regs regs;



	memset(&regs, 0, sizeof(regs));



	regs.r1 = (unsigned long)arg;

	regs.p1 = (unsigned long)fn;

	regs.pc = (unsigned long)kernel_thread_helper;

	regs.orig_p0 = -1;

	/* Set bit 2 to tell ret_from_fork we should be returning to kernel

	   mode.  */

	regs.ipend = 0x8002;

	__asm__ __volatile__("%0 = syscfg;":"=da"(regs.syscfg):);

	return do_fork(flags | CLONE_VM | CLONE_UNTRACED, 0, &regs, 0, NULL,

		       NULL);

}

EXPORT_SYMBOL(kernel_thread);



/*

 * Do necessary setup to start up a newly executed thread.

 *
@@ -193,13 +159,26 @@ copy_thread(unsigned long clone_flags, 
	    struct task_struct *p, struct pt_regs *regs)

{

	struct pt_regs *childregs;

	unsigned long *v;



	childregs = (struct pt_regs *) (task_stack_page(p) + THREAD_SIZE) - 1;

	v = ((unsigned long *)childregs) - 2;

	if (unlikely(!regs)) {

		memset(childregs, 0, sizeof(struct pt_regs));

		v[0] = usp;

		v[1] = topstk;

		childregs->orig_p0 = -1;

		childregs->ipend = 0x8000;

		__asm__ __volatile__("%0 = syscfg;":"=da"(childregs->syscfg):);

		p->thread.usp = 0;

	} else {

		*childregs = *regs;

		childregs->r0 = 0;



		p->thread.usp = usp;

	p->thread.ksp = (unsigned long)childregs;

		v[0] = v[1] = 0;

	}



	p->thread.ksp = (unsigned long)v;

	p->thread.pc = (unsigned long)ret_from_fork;



	return 0;

arch/blackfin/mach-common/entry.S

+0 −55
Original line number Diff line number Diff line
@@ -530,61 +530,6 @@ ENTRY(_trap) /* Exception: 4th entry into system event table(supervisor mode)*/ 
	jump .Lsyscall_really_exit;

ENDPROC(_trap)



ENTRY(_kernel_execve)

	link SIZEOF_PTREGS;

	p0 = sp;

	r3 = SIZEOF_PTREGS / 4;

	r4 = 0(x);

.Lclear_regs:

	[p0++] = r4;

	r3 += -1;

	cc = r3 == 0;

	if !cc jump .Lclear_regs (bp);



	p0 = sp;

	sp += -16;

	[sp + 12] = p0;

	pseudo_long_call _do_execve, p5;

	SP += 16;

	cc = r0 == 0;

	if ! cc jump .Lexecve_failed;

	/* Success.  Copy our temporary pt_regs to the top of the kernel

	 * stack and do a normal exception return.

	 */

	r1 = sp;

	r0 = (-KERNEL_STACK_SIZE) (x);

	r1 = r1 & r0;

	p2 = r1;

	p3 = [p2];

	r0 = KERNEL_STACK_SIZE - 4 (z);

	p1 = r0;

	p1 = p1 + p2;



	p0 = fp;

	r4 = [p0--];

	r3 = SIZEOF_PTREGS / 4;

.Lcopy_regs:

	r4 = [p0--];

	[p1--] = r4;

	r3 += -1;

	cc = r3 == 0;

	if ! cc jump .Lcopy_regs (bp);



	r0 = (KERNEL_STACK_SIZE - SIZEOF_PTREGS) (z);

	p1 = r0;

	p1 = p1 + p2;

	sp = p1;

	r0 = syscfg;

	[SP + PT_SYSCFG] = r0;

	[p3 + (TASK_THREAD + THREAD_KSP)] = sp;



	RESTORE_CONTEXT;

	rti;

.Lexecve_failed:

	unlink;

	rts;

ENDPROC(_kernel_execve)



ENTRY(_system_call)

	/* Store IPEND */

	p2.l = lo(IPEND);