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-rw-r--r--arch/mips/kernel/r4k_switch.S59
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diff --git a/arch/mips/kernel/r4k_switch.S b/arch/mips/kernel/r4k_switch.S
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+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 1994, 1995, 1996, 1998, 1999, 2002, 2003 Ralf Baechle
+ * Copyright (C) 1996 David S. Miller (davem@davemloft.net)
+ * Copyright (C) 1994, 1995, 1996, by Andreas Busse
+ * Copyright (C) 1999 Silicon Graphics, Inc.
+ * Copyright (C) 2000 MIPS Technologies, Inc.
+ * written by Carsten Langgaard, carstenl@mips.com
+ */
+#include <asm/asm.h>
+#include <asm/cachectl.h>
+#include <asm/mipsregs.h>
+#include <asm/asm-offsets.h>
+#include <asm/regdef.h>
+#include <asm/stackframe.h>
+#include <asm/thread_info.h>
+
+#include <asm/asmmacro.h>
+
+/*
+ * task_struct *resume(task_struct *prev, task_struct *next,
+ * struct thread_info *next_ti)
+ */
+ .align 5
+ LEAF(resume)
+ mfc0 t1, CP0_STATUS
+ LONG_S t1, THREAD_STATUS(a0)
+ cpu_save_nonscratch a0
+ LONG_S ra, THREAD_REG31(a0)
+
+#if defined(CONFIG_STACKPROTECTOR) && !defined(CONFIG_SMP)
+ PTR_LA t8, __stack_chk_guard
+ LONG_L t9, TASK_STACK_CANARY(a1)
+ LONG_S t9, 0(t8)
+#endif
+
+ /*
+ * The order of restoring the registers takes care of the race
+ * updating $28, $29 and kernelsp without disabling ints.
+ */
+ move $28, a2
+ cpu_restore_nonscratch a1
+
+ PTR_ADDU t0, $28, _THREAD_SIZE - 32
+ set_saved_sp t0, t1, t2
+ mfc0 t1, CP0_STATUS /* Do we really need this? */
+ li a3, 0xff01
+ and t1, a3
+ LONG_L a2, THREAD_STATUS(a1)
+ nor a3, $0, a3
+ and a2, a3
+ or a2, t1
+ mtc0 a2, CP0_STATUS
+ move v0, a0
+ jr ra
+ END(resume)