This simplifies __switch_to_xtra, and will make it easier to make IO
optional later.
Signed-off-by: Josh Triplett <josh@xxxxxxxxxxxxxxxx>
---
arch/x86/kernel/process-io.h | 23 +++++++++++++++++++++++
arch/x86/kernel/process.c | 14 +-------------
2 files changed, 24 insertions(+), 13 deletions(-)
diff --git a/arch/x86/kernel/process-io.h b/arch/x86/kernel/process-io.h
index 012c1d5..e48d5c9 100644
--- a/arch/x86/kernel/process-io.h
+++ b/arch/x86/kernel/process-io.h
@@ -57,4 +57,27 @@ static inline void switch_iopl_mask(struct thread_struct *prev,
set_iopl_mask(next->iopl);
}
+static inline void switch_io_bitmap(struct tss_struct *tss,
+ struct task_struct *prev_p,
+ struct task_struct *next_p)
+{
+ struct thread_struct *prev, *next;
+ prev = &prev_p->thread;
+ next = &next_p->thread;
+
+ if (test_tsk_thread_flag(next_p, TIF_IO_BITMAP)) {
+ /*
+ * Copy the relevant range of the IO bitmap.
+ * Normally this is 128 bytes or less:
+ */
+ memcpy(tss->io_bitmap, next->io_bitmap_ptr,
+ max(prev->io_bitmap_max, next->io_bitmap_max));
+ } else if (test_tsk_thread_flag(prev_p, TIF_IO_BITMAP)) {
+ /*
+ * Clear any possible leftover bits:
+ */
+ memset(tss->io_bitmap, 0xff, prev->io_bitmap_max);
+ }
+}
+
#endif /* _X86_KERNEL_PROCESS_IO_H */
diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c
index 37b45ca..7ac01bf 100644
--- a/arch/x86/kernel/process.c
+++ b/arch/x86/kernel/process.c
@@ -211,19 +211,7 @@ void __switch_to_xtra(struct task_struct *prev_p, struct task_struct *next_p,
hard_enable_TSC();
}
- if (test_tsk_thread_flag(next_p, TIF_IO_BITMAP)) {
- /*
- * Copy the relevant range of the IO bitmap.
- * Normally this is 128 bytes or less:
- */
- memcpy(tss->io_bitmap, next->io_bitmap_ptr,
- max(prev->io_bitmap_max, next->io_bitmap_max));
- } else if (test_tsk_thread_flag(prev_p, TIF_IO_BITMAP)) {
- /*
- * Clear any possible leftover bits:
- */
- memset(tss->io_bitmap, 0xff, prev->io_bitmap_max);
- }
+ switch_io_bitmap(tss, prev_p, next_p);
propagate_user_return_notify(prev_p, next_p);
}
--
2.1.1
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