aboutsummaryrefslogtreecommitdiff
path: root/arch/x86/kernel/ioport_32.c
diff options
context:
space:
mode:
authormboton@gmail.com <mboton@gmail.com>2008-01-30 13:33:10 +0100
committerIngo Molnar <mingo@elte.hu>2008-01-30 13:33:10 +0100
commitccafa59a0061d7c44d15d02403120fd02b52c667 (patch)
tree46783be3e882843ea2057697a28b97de4bdea1f8 /arch/x86/kernel/ioport_32.c
parentaaf230424204864e2833dcc1da23e2cb0b9f39cd (diff)
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: Miguel Botón <mboton@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Diffstat (limited to 'arch/x86/kernel/ioport_32.c')
-rw-r--r--arch/x86/kernel/ioport_32.c129
1 files changed, 0 insertions, 129 deletions
diff --git a/arch/x86/kernel/ioport_32.c b/arch/x86/kernel/ioport_32.c
deleted file mode 100644
index 9295e01ff49..00000000000
--- a/arch/x86/kernel/ioport_32.c
+++ /dev/null
@@ -1,129 +0,0 @@
-/*
- * 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)
-{
- unsigned int i;
-
- for (i = base; i < base + extent; i++) {
- if (new_value)
- __set_bit(i, bitmap);
- else
- __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)
-{
- struct thread_struct * t = &current->thread;
- struct tss_struct * tss;
- unsigned long i, max_long;
-
- 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) {
- unsigned long *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;
-
- t->io_bitmap_max = (max_long + 1) * sizeof(unsigned long);
-
- /*
- * Sets the lazy trigger so that the next I/O operation will
- * reload the correct bitmap.
- * Reset the owner so that a process switch will not set
- * tss->io_bitmap_base to IO_BITMAP_OFFSET.
- */
- tss->x86_tss.io_bitmap_base = INVALID_IO_BITMAP_OFFSET_LAZY;
- tss->io_bitmap_owner = NULL;
-
- 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 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;
- /* Trying to gain more privileges? */
- if (level > old) {
- if (!capable(CAP_SYS_RAWIO))
- return -EPERM;
- }
-
- t->iopl = level << 12;
- regs->flags = (regs->flags & ~X86_EFLAGS_IOPL) | t->iopl;
- set_iopl_mask(t->iopl);
-
- return 0;
-}