Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit ccafa59a authored by mboton@gmail.com's avatar mboton@gmail.com Committed by Ingo Molnar
Browse files

x86: ioport_{32|64}.c unification 



ioport_{32|64}.c unification.

This patch unifies the code from the ioport_32.c and ioport_64.c files.

Tested and working fine with i386 and x86_64 kernels.

Signed-off-by: default avatarMiguel Botón <mboton@gmail.com>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
parent aaf23042

arch/x86/kernel/Makefile

+1 −1
Original line number Diff line number Diff line
@@ -10,7 +10,7 @@ CFLAGS_vsyscall_64.o := $(PROFILING) -g0 


obj-y			:= process_$(BITS).o signal_$(BITS).o entry_$(BITS).o

obj-y			+= traps_$(BITS).o irq_$(BITS).o

obj-y			+= time_$(BITS).o ioport_$(BITS).o ldt.o

obj-y			+= time_$(BITS).o ioport.o ldt.o

obj-y			+= setup_$(BITS).o i8259_$(BITS).o

obj-$(CONFIG_X86_32)	+= sys_i386_32.o i386_ksyms_32.o

obj-$(CONFIG_X86_64)	+= sys_x86_64.o x8664_ksyms_64.o

arch/x86/kernel/ioport_32.c→arch/x86/kernel/ioport.c

+29 −8
Original line number Diff line number Diff line 
/*

 * This contains the io-permission bitmap code - written by obz, with changes

 * by Linus.

 * by Linus. 32/64 bits code unification by Miguel Botón.

 */



#include <linux/sched.h>
@@ -36,7 +36,7 @@ asmlinkage long sys_ioperm(unsigned long from, unsigned long num, int turn_on) 
{

	struct thread_struct * t = &current->thread;

	struct tss_struct * tss;

	unsigned long i, max_long;

	unsigned int i, max_long, bytes, bytes_updated;



	if ((from + num <= from) || (from + num > IO_BITMAP_BITS))

		return -EINVAL;
@@ -79,8 +79,12 @@ asmlinkage long sys_ioperm(unsigned long from, unsigned long num, int turn_on) 
		if (t->io_bitmap_ptr[i] != ~0UL)

			max_long = i;



	t->io_bitmap_max = (max_long + 1) * sizeof(unsigned long);

	bytes = (max_long + 1) * sizeof(unsigned long);

	bytes_updated = max(bytes, t->io_bitmap_max);



	t->io_bitmap_max = bytes;



#ifdef CONFIG_X86_32

	/*

	 * Sets the lazy trigger so that the next I/O operation will

	 * reload the correct bitmap.
@@ -89,6 +93,10 @@ asmlinkage long sys_ioperm(unsigned long from, unsigned long num, int turn_on) 
	 */

	tss->x86_tss.io_bitmap_base = INVALID_IO_BITMAP_OFFSET_LAZY;

	tss->io_bitmap_owner = NULL;

#else

	/* Update the TSS: */

	memcpy(tss->io_bitmap, t->io_bitmap_ptr, bytes_updated);

#endif



	put_cpu();
@@ -105,13 +113,12 @@ asmlinkage long sys_ioperm(unsigned long from, unsigned long num, int turn_on) 
 * on system-call entry - see also fork() and the signal handling

 * code.

 */



#ifdef CONFIG_X86_32

asmlinkage long sys_iopl(unsigned long regsp)

{

	volatile struct pt_regs *regs = (struct pt_regs *)&regsp;

	unsigned int level = regs->bx;

	unsigned int old = (regs->flags >> 12) & 3;

	struct thread_struct *t = &current->thread;



	if (level > 3)

		return -EINVAL;
@@ -120,10 +127,24 @@ asmlinkage long sys_iopl(unsigned long regsp) 
		if (!capable(CAP_SYS_RAWIO))

			return -EPERM;

	}

	regs->flags = (regs->flags & ~X86_EFLAGS_IOPL) | (level << 12);



	return 0;

}

#else

asmlinkage long sys_iopl(unsigned int level, struct pt_regs *regs)

{

	unsigned int old = (regs->flags >> 12) & 3;



	t->iopl = level << 12;

	regs->flags = (regs->flags & ~X86_EFLAGS_IOPL) | t->iopl;

	set_iopl_mask(t->iopl);

	if (level > 3)

		return -EINVAL;

	/* Trying to gain more privileges? */

	if (level > old) {

		if (!capable(CAP_SYS_RAWIO))

			return -EPERM;

	}

	regs->flags = (regs->flags & ~X86_EFLAGS_IOPL) | (level << 12);



	return 0;

}

#endif

arch/x86/kernel/ioport_64.c

deleted100644 → 0
+0 −117
Original line number Diff line number Diff line 
/*

 * This contains the io-permission bitmap code - written by obz, with changes

 * by Linus.

 */



#include <linux/sched.h>

#include <linux/kernel.h>

#include <linux/capability.h>

#include <linux/errno.h>

#include <linux/types.h>

#include <linux/ioport.h>

#include <linux/smp.h>

#include <linux/stddef.h>

#include <linux/slab.h>

#include <linux/thread_info.h>

#include <linux/syscalls.h>



/* Set EXTENT bits starting at BASE in BITMAP to value TURN_ON. */

static void set_bitmap(unsigned long *bitmap, unsigned int base, unsigned int extent, int new_value)

{

	int i;

		if (new_value)

		for (i = base; i < base + extent; i++) 

			__set_bit(i, bitmap); 

		else

		for (i = base; i < base + extent; i++) 

			clear_bit(i, bitmap); 

}



/*

 * this changes the io permissions bitmap in the current task.

 */

asmlinkage long sys_ioperm(unsigned long from, unsigned long num, int turn_on)

{

	unsigned int i, max_long, bytes, bytes_updated;

	struct thread_struct * t = &current->thread;

	struct tss_struct * tss;

	unsigned long *bitmap;



	if ((from + num <= from) || (from + num > IO_BITMAP_BITS))

		return -EINVAL;

	if (turn_on && !capable(CAP_SYS_RAWIO))

		return -EPERM;



	/*

	 * If it's the first ioperm() call in this thread's lifetime, set the

	 * IO bitmap up. ioperm() is much less timing critical than clone(),

	 * this is why we delay this operation until now:

	 */

	if (!t->io_bitmap_ptr) {

		bitmap = kmalloc(IO_BITMAP_BYTES, GFP_KERNEL);

		if (!bitmap)

			return -ENOMEM;



		memset(bitmap, 0xff, IO_BITMAP_BYTES);

		t->io_bitmap_ptr = bitmap;

		set_thread_flag(TIF_IO_BITMAP);

	}



	/*

	 * do it in the per-thread copy and in the TSS ...

	 *

	 * Disable preemption via get_cpu() - we must not switch away

	 * because the ->io_bitmap_max value must match the bitmap

	 * contents:

	 */

	tss = &per_cpu(init_tss, get_cpu());



	set_bitmap(t->io_bitmap_ptr, from, num, !turn_on);



	/*

	 * Search for a (possibly new) maximum. This is simple and stupid,

	 * to keep it obviously correct:

	 */

	max_long = 0;

	for (i = 0; i < IO_BITMAP_LONGS; i++)

		if (t->io_bitmap_ptr[i] != ~0UL)

			max_long = i;



	bytes = (max_long + 1) * sizeof(long);

	bytes_updated = max(bytes, t->io_bitmap_max);



	t->io_bitmap_max = bytes;



	/* Update the TSS: */

	memcpy(tss->io_bitmap, t->io_bitmap_ptr, bytes_updated);



	put_cpu();



	return 0;

}



/*

 * sys_iopl has to be used when you want to access the IO ports

 * beyond the 0x3ff range: to get the full 65536 ports bitmapped

 * you'd need 8kB of bitmaps/process, which is a bit excessive.

 *

 * Here we just change the flags value on the stack: we allow

 * only the super-user to do it. This depends on the stack-layout

 * on system-call entry - see also fork() and the signal handling

 * code.

 */



asmlinkage long sys_iopl(unsigned int level, struct pt_regs *regs)

{

	unsigned int old = (regs->flags >> 12) & 3;



	if (level > 3)

		return -EINVAL;

	/* Trying to gain more privileges? */

	if (level > old) {

		if (!capable(CAP_SYS_RAWIO))

			return -EPERM;

	}

	regs->flags = (regs->flags &~ X86_EFLAGS_IOPL) | (level << 12);

	return 0;

}