Commit 415ddc3b authored by Al Viro's avatar Al Viro
Browse files

sparc32: take ->thread.flags out 



it was used for two things - dealing with unusual ->kregs for kernel
threads and "emulate unaligned userland accesses for this thread";
the former is killed off by the previous commit, the latter never
had been set in the first place.

Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
parent af765250

arch/sparc/include/asm/processor_32.h

+0 −5
Original line number Diff line number Diff line
@@ -50,15 +50,10 @@ struct thread_struct { 
	unsigned long   fsr;

	unsigned long   fpqdepth;

	struct fpq	fpqueue[16];

	unsigned long flags;

	mm_segment_t current_ds;

};



#define SPARC_FLAG_KTHREAD      0x1    /* task is a kernel thread */

#define SPARC_FLAG_UNALIGNED    0x2    /* is allowed to do unaligned accesses */



#define INIT_THREAD  { \

	.flags = SPARC_FLAG_KTHREAD, \

	.current_ds = KERNEL_DS, \

	.kregs = (struct pt_regs *)(init_stack+THREAD_SIZE)-1 \

}

arch/sparc/kernel/process_32.c

+0 −5
Original line number Diff line number Diff line
@@ -216,9 +216,6 @@ void flush_thread(void) 
		clear_thread_flag(TIF_USEDFPU);

#endif

	}



	/* This task is no longer a kernel thread. */

	current->thread.flags &= ~SPARC_FLAG_KTHREAD;

}



static inline struct sparc_stackf __user *
@@ -306,7 +303,6 @@ int copy_thread(unsigned long clone_flags, unsigned long sp, unsigned long arg, 
		extern int nwindows;

		unsigned long psr;

		memset(new_stack, 0, STACKFRAME_SZ + TRACEREG_SZ);

		p->thread.flags |= SPARC_FLAG_KTHREAD;

		p->thread.current_ds = KERNEL_DS;

		ti->kpc = (((unsigned long) ret_from_kernel_thread) - 0x8);

		childregs->u_regs[UREG_G1] = sp; /* function */
@@ -318,7 +314,6 @@ int copy_thread(unsigned long clone_flags, unsigned long sp, unsigned long arg, 
	}

	memcpy(new_stack, (char *)regs - STACKFRAME_SZ, STACKFRAME_SZ + TRACEREG_SZ);

	childregs->u_regs[UREG_FP] = sp;

	p->thread.flags &= ~SPARC_FLAG_KTHREAD;

	p->thread.current_ds = USER_DS;

	ti->kpc = (((unsigned long) ret_from_fork) - 0x8);

	ti->kpsr = current->thread.fork_kpsr | PSR_PIL;

arch/sparc/kernel/unaligned_32.c

+1 −95
Original line number Diff line number Diff line
@@ -274,103 +274,9 @@ asmlinkage void kernel_unaligned_trap(struct pt_regs *regs, unsigned int insn) 
	}

}



static inline int ok_for_user(struct pt_regs *regs, unsigned int insn,

			      enum direction dir)

{

	unsigned int reg;

	int size = ((insn >> 19) & 3) == 3 ? 8 : 4;



	if ((regs->pc | regs->npc) & 3)

		return 0;



	/* Must access_ok() in all the necessary places. */

#define WINREG_ADDR(regnum) \

	((void __user *)(((unsigned long *)regs->u_regs[UREG_FP])+(regnum)))



	reg = (insn >> 25) & 0x1f;

	if (reg >= 16) {

		if (!access_ok(WINREG_ADDR(reg - 16), size))

			return -EFAULT;

	}

	reg = (insn >> 14) & 0x1f;

	if (reg >= 16) {

		if (!access_ok(WINREG_ADDR(reg - 16), size))

			return -EFAULT;

	}

	if (!(insn & 0x2000)) {

		reg = (insn & 0x1f);

		if (reg >= 16) {

			if (!access_ok(WINREG_ADDR(reg - 16), size))

				return -EFAULT;

		}

	}

#undef WINREG_ADDR

	return 0;

}



static void user_mna_trap_fault(struct pt_regs *regs, unsigned int insn)

asmlinkage void user_unaligned_trap(struct pt_regs *regs, unsigned int insn)

{

	send_sig_fault(SIGBUS, BUS_ADRALN,

		       (void __user *)safe_compute_effective_address(regs, insn),

		       0, current);

}
 


asmlinkage void user_unaligned_trap(struct pt_regs *regs, unsigned int insn)

{

	enum direction dir;



	if(!(current->thread.flags & SPARC_FLAG_UNALIGNED) ||

	   (((insn >> 30) & 3) != 3))

		goto kill_user;

	dir = decode_direction(insn);

	if(!ok_for_user(regs, insn, dir)) {

		goto kill_user;

	} else {

		int err, size = decode_access_size(insn);

		unsigned long addr;



		if(floating_point_load_or_store_p(insn)) {

			printk("User FPU load/store unaligned unsupported.\n");

			goto kill_user;

		}



		addr = compute_effective_address(regs, insn);

		perf_sw_event(PERF_COUNT_SW_ALIGNMENT_FAULTS, 1, regs, addr);

		switch(dir) {

		case load:

			err = do_int_load(fetch_reg_addr(((insn>>25)&0x1f),

							 regs),

					  size, (unsigned long *) addr,

					  decode_signedness(insn));

			break;



		case store:

			err = do_int_store(((insn>>25)&0x1f), size,

					   (unsigned long *) addr, regs);

			break;



		case both:

			/*

			 * This was supported in 2.4. However, we question

			 * the value of SWAP instruction across word boundaries.

			 */

			printk("Unaligned SWAP unsupported.\n");

			err = -EFAULT;

			break;



		default:

			unaligned_panic("Impossible user unaligned trap.");

			goto out;

		}

		if (err)

			goto kill_user;

		else

			advance(regs);

		goto out;

	}



kill_user:

	user_mna_trap_fault(regs, insn);

out:

	;

}