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

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
......@@ -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
......
/*
* 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
/*
* 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;
}
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