Linux-2.6.12-rc2v2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 251 insertions, 0 deletions

diff --git a/include/asm-s390/spinlock.h b/include/asm-s390/spinlock.h
new file mode 100644
index 000000000000..53cc736b9820
--- /dev/null
+++ b/include/asm-s390/spinlock.h
@@ -0,0 +1,251 @@
+/*
+ *  include/asm-s390/spinlock.h
+ *
+ *  S390 version
+ *    Copyright (C) 1999 IBM Deutschland Entwicklung GmbH, IBM Corporation
+ *    Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com)
+ *
+ *  Derived from "include/asm-i386/spinlock.h"
+ */
+
+#ifndef __ASM_SPINLOCK_H
+#define __ASM_SPINLOCK_H
+
+#ifdef __s390x__
+/*
+ * Grmph, take care of %&#! user space programs that include
+ * asm/spinlock.h. The diagnose is only available in kernel
+ * context.
+ */
+#ifdef __KERNEL__
+#include <asm/lowcore.h>
+#define __DIAG44_INSN "ex"
+#define __DIAG44_OPERAND __LC_DIAG44_OPCODE
+#else
+#define __DIAG44_INSN "#"
+#define __DIAG44_OPERAND 0
+#endif
+#endif /* __s390x__ */
+
+/*
+ * Simple spin lock operations.  There are two variants, one clears IRQ's
+ * on the local processor, one does not.
+ *
+ * We make no fairness assumptions. They have a cost.
+ */
+
+typedef struct {
+        volatile unsigned int lock;
+#ifdef CONFIG_PREEMPT
+        unsigned int break_lock;
+#endif
+} __attribute__ ((aligned (4))) spinlock_t;
+
+#define SPIN_LOCK_UNLOCKED (spinlock_t) { 0 }
+#define spin_lock_init(lp) do { (lp)->lock = 0; } while(0)
+#define spin_unlock_wait(lp)    do { barrier(); } while(((volatile spinlock_t *)(lp))->lock)
+#define spin_is_locked(x) ((x)->lock != 0)
+#define _raw_spin_lock_flags(lock, flags) _raw_spin_lock(lock)
+
+extern inline void _raw_spin_lock(spinlock_t *lp)
+{
+#ifndef __s390x__
+        unsigned int reg1, reg2;
+        __asm__ __volatile__("    bras  %0,1f\n"
+                           "0:  diag  0,0,68\n"
+                           "1:  slr   %1,%1\n"
+                           "    cs    %1,%0,0(%3)\n"
+                           "    jl    0b\n"
+                           : "=&d" (reg1), "=&d" (reg2), "=m" (lp->lock)
+                           : "a" (&lp->lock), "m" (lp->lock)
+                           : "cc", "memory" );
+#else /* __s390x__ */
+        unsigned long reg1, reg2;
+        __asm__ __volatile__("    bras  %1,1f\n"
+                           "0:  " __DIAG44_INSN " 0,%4\n"
+                           "1:  slr   %0,%0\n"
+                           "    cs    %0,%1,0(%3)\n"
+                           "    jl    0b\n"
+                           : "=&d" (reg1), "=&d" (reg2), "=m" (lp->lock)
+                           : "a" (&lp->lock), "i" (__DIAG44_OPERAND),
+                             "m" (lp->lock) : "cc", "memory" );
+#endif /* __s390x__ */
+}
+
+extern inline int _raw_spin_trylock(spinlock_t *lp)
+{
+        unsigned long reg;
+        unsigned int result;
+
+        __asm__ __volatile__("    basr  %1,0\n"
+                           "0:  cs    %0,%1,0(%3)"
+                           : "=d" (result), "=&d" (reg), "=m" (lp->lock)
+                           : "a" (&lp->lock), "m" (lp->lock), "0" (0)
+                           : "cc", "memory" );
+        return !result;
+}
+
+extern inline void _raw_spin_unlock(spinlock_t *lp)
+{
+        unsigned int old;
+
+        __asm__ __volatile__("cs %0,%3,0(%4)"
+                           : "=d" (old), "=m" (lp->lock)
+                           : "0" (lp->lock), "d" (0), "a" (lp)
+                           : "cc", "memory" );
+}
+                
+/*
+ * Read-write spinlocks, allowing multiple readers
+ * but only one writer.
+ *
+ * NOTE! it is quite common to have readers in interrupts
+ * but no interrupt writers. For those circumstances we
+ * can "mix" irq-safe locks - any writer needs to get a
+ * irq-safe write-lock, but readers can get non-irqsafe
+ * read-locks.
+ */
+typedef struct {
+        volatile unsigned long lock;
+        volatile unsigned long owner_pc;
+#ifdef CONFIG_PREEMPT
+        unsigned int break_lock;
+#endif
+} rwlock_t;
+
+#define RW_LOCK_UNLOCKED (rwlock_t) { 0, 0 }
+
+#define rwlock_init(x)  do { *(x) = RW_LOCK_UNLOCKED; } while(0)
+
+/**
+ * read_can_lock - would read_trylock() succeed?
+ * @lock: the rwlock in question.
+ */
+#define read_can_lock(x) ((int)(x)->lock >= 0)
+
+/**
+ * write_can_lock - would write_trylock() succeed?
+ * @lock: the rwlock in question.
+ */
+#define write_can_lock(x) ((x)->lock == 0)
+
+#ifndef __s390x__
+#define _raw_read_lock(rw)   \
+        asm volatile("   l     2,0(%1)\n"   \
+                     "   j     1f\n"     \
+                     "0: diag  0,0,68\n" \
+                     "1: la    2,0(2)\n"     /* clear high (=write) bit */ \
+                     "   la    3,1(2)\n"     /* one more reader */ \
+                     "   cs    2,3,0(%1)\n"  /* try to write new value */ \
+                     "   jl    0b"       \
+                     : "=m" ((rw)->lock) : "a" (&(rw)->lock), \
+                       "m" ((rw)->lock) : "2", "3", "cc", "memory" )
+#else /* __s390x__ */
+#define _raw_read_lock(rw)   \
+        asm volatile("   lg    2,0(%1)\n"   \
+                     "   j     1f\n"     \
+                     "0: " __DIAG44_INSN " 0,%2\n" \
+                     "1: nihh  2,0x7fff\n" /* clear high (=write) bit */ \
+                     "   la    3,1(2)\n"   /* one more reader */  \
+                     "   csg   2,3,0(%1)\n" /* try to write new value */ \
+                     "   jl    0b"       \
+                     : "=m" ((rw)->lock) \
+                     : "a" (&(rw)->lock), "i" (__DIAG44_OPERAND), \
+                       "m" ((rw)->lock) : "2", "3", "cc", "memory" )
+#endif /* __s390x__ */
+
+#ifndef __s390x__
+#define _raw_read_unlock(rw) \
+        asm volatile("   l     2,0(%1)\n"   \
+                     "   j     1f\n"     \
+                     "0: diag  0,0,68\n" \
+                     "1: lr    3,2\n"    \
+                     "   ahi   3,-1\n"    /* one less reader */ \
+                     "   cs    2,3,0(%1)\n" \
+                     "   jl    0b"       \
+                     : "=m" ((rw)->lock) : "a" (&(rw)->lock), \
+                       "m" ((rw)->lock) : "2", "3", "cc", "memory" )
+#else /* __s390x__ */
+#define _raw_read_unlock(rw) \
+        asm volatile("   lg    2,0(%1)\n"   \
+                     "   j     1f\n"     \
+                     "0: " __DIAG44_INSN " 0,%2\n" \
+                     "1: lgr   3,2\n"    \
+                     "   bctgr 3,0\n"    /* one less reader */ \
+                     "   csg   2,3,0(%1)\n" \
+                     "   jl    0b"       \
+                     : "=m" ((rw)->lock) \
+                     : "a" (&(rw)->lock), "i" (__DIAG44_OPERAND), \
+                       "m" ((rw)->lock) : "2", "3", "cc", "memory" )
+#endif /* __s390x__ */
+
+#ifndef __s390x__
+#define _raw_write_lock(rw) \
+        asm volatile("   lhi   3,1\n"    \
+                     "   sll   3,31\n"    /* new lock value = 0x80000000 */ \
+                     "   j     1f\n"     \
+                     "0: diag  0,0,68\n" \
+                     "1: slr   2,2\n"     /* old lock value must be 0 */ \
+                     "   cs    2,3,0(%1)\n" \
+                     "   jl    0b"       \
+                     : "=m" ((rw)->lock) : "a" (&(rw)->lock), \
+                       "m" ((rw)->lock) : "2", "3", "cc", "memory" )
+#else /* __s390x__ */
+#define _raw_write_lock(rw) \
+        asm volatile("   llihh 3,0x8000\n" /* new lock value = 0x80...0 */ \
+                     "   j     1f\n"       \
+                     "0: " __DIAG44_INSN " 0,%2\n"   \
+                     "1: slgr  2,2\n"      /* old lock value must be 0 */ \
+                     "   csg   2,3,0(%1)\n" \
+                     "   jl    0b"         \
+                     : "=m" ((rw)->lock) \
+                     : "a" (&(rw)->lock), "i" (__DIAG44_OPERAND), \
+                       "m" ((rw)->lock) : "2", "3", "cc", "memory" )
+#endif /* __s390x__ */
+
+#ifndef __s390x__
+#define _raw_write_unlock(rw) \
+        asm volatile("   slr   3,3\n"     /* new lock value = 0 */ \
+                     "   j     1f\n"     \
+                     "0: diag  0,0,68\n" \
+                     "1: lhi   2,1\n"    \
+                     "   sll   2,31\n"    /* old lock value must be 0x80000000 */ \
+                     "   cs    2,3,0(%1)\n" \
+                     "   jl    0b"       \
+                     : "=m" ((rw)->lock) : "a" (&(rw)->lock), \
+                       "m" ((rw)->lock) : "2", "3", "cc", "memory" )
+#else /* __s390x__ */
+#define _raw_write_unlock(rw) \
+        asm volatile("   slgr  3,3\n"      /* new lock value = 0 */ \
+                     "   j     1f\n"       \
+                     "0: " __DIAG44_INSN " 0,%2\n"   \
+                     "1: llihh 2,0x8000\n" /* old lock value must be 0x8..0 */\
+                     "   csg   2,3,0(%1)\n"   \
+                     "   jl    0b"         \
+                     : "=m" ((rw)->lock) \
+                     : "a" (&(rw)->lock), "i" (__DIAG44_OPERAND), \
+                       "m" ((rw)->lock) : "2", "3", "cc", "memory" )
+#endif /* __s390x__ */
+
+#define _raw_read_trylock(lock) generic_raw_read_trylock(lock)
+
+extern inline int _raw_write_trylock(rwlock_t *rw)
+{
+        unsigned long result, reg;
+        
+        __asm__ __volatile__(
+#ifndef __s390x__
+                             "   lhi  %1,1\n"
+                             "   sll  %1,31\n"
+                             "   cs   %0,%1,0(%3)"
+#else /* __s390x__ */
+                             "   llihh %1,0x8000\n"
+                             "0: csg %0,%1,0(%3)\n"
+#endif /* __s390x__ */
+                             : "=d" (result), "=&d" (reg), "=m" (rw->lock)
+                             : "a" (&rw->lock), "m" (rw->lock), "0" (0UL)
+                             : "cc", "memory" );
+        return result == 0;
+}
+
+#endif /* __ASM_SPINLOCK_H */