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Subject[PATCH] x86/ioperm: Save an indentation level in tss_update_io_bitmap()
Date
From: Borislav Petkov <bp@suse.de>

... for better readability.

No functional changes.

Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86@kernel.org
---
arch/x86/kernel/process.c | 52 +++++++++++++++++++--------------------
1 file changed, 26 insertions(+), 26 deletions(-)

diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c
index bd2a11ca5dd6..17ef878fd5dd 100644
--- a/arch/x86/kernel/process.c
+++ b/arch/x86/kernel/process.c
@@ -377,37 +377,37 @@ static void tss_copy_io_bitmap(struct tss_struct *tss, struct io_bitmap *iobm)
void tss_update_io_bitmap(void)
{
struct tss_struct *tss = this_cpu_ptr(&cpu_tss_rw);
+ struct thread_struct *t = &current->thread;
u16 *base = &tss->x86_tss.io_bitmap_base;

- if (test_thread_flag(TIF_IO_BITMAP)) {
- struct thread_struct *t = &current->thread;
-
- if (IS_ENABLED(CONFIG_X86_IOPL_IOPERM) && t->iopl_emul == 3) {
- *base = IO_BITMAP_OFFSET_VALID_ALL;
- } else {
- struct io_bitmap *iobm = t->io_bitmap;
- /*
- * Only copy bitmap data when the sequence number
- * differs. The update time is accounted to the
- * incoming task.
- */
- if (tss->io_bitmap.prev_sequence != iobm->sequence)
- tss_copy_io_bitmap(tss, iobm);
-
- /* Enable the bitmap */
- *base = IO_BITMAP_OFFSET_VALID_MAP;
- }
+ if (!test_thread_flag(TIF_IO_BITMAP)) {
+ tss_invalidate_io_bitmap(tss);
+ return;
+ }
+
+ if (IS_ENABLED(CONFIG_X86_IOPL_IOPERM) && t->iopl_emul == 3) {
+ *base = IO_BITMAP_OFFSET_VALID_ALL;
+ } else {
+ struct io_bitmap *iobm = t->io_bitmap;
+
/*
- * Make sure that the TSS limit is covering the io bitmap.
- * It might have been cut down by a VMEXIT to 0x67 which
- * would cause a subsequent I/O access from user space to
- * trigger a #GP because tbe bitmap is outside the TSS
- * limit.
+ * Only copy bitmap data when the sequence number differs. The
+ * update time is accounted to the incoming task.
*/
- refresh_tss_limit();
- } else {
- tss_invalidate_io_bitmap(tss);
+ if (tss->io_bitmap.prev_sequence != iobm->sequence)
+ tss_copy_io_bitmap(tss, iobm);
+
+ /* Enable the bitmap */
+ *base = IO_BITMAP_OFFSET_VALID_MAP;
}
+
+ /*
+ * Make sure that the TSS limit is covering the io bitmap. It might have
+ * been cut down by a VMEXIT to 0x67 which would cause a subsequent I/O
+ * access from user space to trigger a #GP because tbe bitmap is outside
+ * the TSS limit.
+ */
+ refresh_tss_limit();
}
#else /* CONFIG_X86_IOPL_IOPERM */
static inline void switch_to_bitmap(unsigned long tifp) { }
--
2.21.0
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