Merge branch 'for-linus' of git://git390.marist.edu/pub/scm/linux-2.6

* 'for-linus' of git://git390.marist.edu/pub/scm/linux-2.6:
  [S390] fill out file list in s390 MAINTAINERS entry
  [S390] Add support for LZO-compressed kernels.
  [S390] cmm: get rid of CMM_PROC config option
  [S390] cmm: remove superfluous EXPORT_SYMBOLs plus cleanups
  [S390] dasd: unit check handling during internal cio I/O
  [S390] cio: unit check handling during internal I/O
  [S390] ccwgroup: add locking around drvdata access
  [S390] cio: remove stsch
  [S390] spp: remove KVM_AWARE_CMF config option
  [S390] kprobes: forbid probing of stnsm/stosm/epsw
  [S390] spp: fix compilation for CONFIG_32BIT
  [S390] atomic: implement atomic64_dec_if_positive
  [S390] cmm: fix crash on module unload

2 files changed, 29 insertions, 0 deletions

diff --git a/arch/s390/include/asm/atomic.h b/arch/s390/include/asm/atomic.h
index 451bfbb9db3d..76daea117181 100644
--- a/arch/s390/include/asm/atomic.h
+++ b/arch/s390/include/asm/atomic.h
@@ -15,6 +15,7 @@
 
 #include <linux/compiler.h>
 #include <linux/types.h>
+#include <asm/system.h>
 
 #define ATOMIC_INIT(i)  { (i) }
 
@@ -274,6 +275,7 @@ static inline void atomic64_clear_mask(unsigned long long mask, atomic64_t *v)
 static inline int atomic64_add_unless(atomic64_t *v, long long a, long long u)
 {
         long long c, old;
+
         c = atomic64_read(v);
         for (;;) {
                 if (unlikely(c == u))
@@ -286,6 +288,23 @@ static inline int atomic64_add_unless(atomic64_t *v, long long a, long long u)
         return c != u;
 }
 
+static inline long long atomic64_dec_if_positive(atomic64_t *v)
+{
+        long long c, old, dec;
+
+        c = atomic64_read(v);
+        for (;;) {
+                dec = c - 1;
+                if (unlikely(dec < 0))
+                        break;
+                old = atomic64_cmpxchg((v), c, dec);
+                if (likely(old == c))
+                        break;
+                c = old;
+        }
+        return dec;
+}
+
 #define atomic64_add(_i, _v)            atomic64_add_return(_i, _v)
 #define atomic64_add_negative(_i, _v)   (atomic64_add_return(_i, _v) < 0)
 #define atomic64_inc(_v)                atomic64_add_return(1, _v)
diff --git a/arch/s390/include/asm/ccwdev.h b/arch/s390/include/asm/ccwdev.h
index f4bd346a52d3..1c0030f9b890 100644
--- a/arch/s390/include/asm/ccwdev.h
+++ b/arch/s390/include/asm/ccwdev.h
@@ -91,6 +91,14 @@ struct ccw_device {
         void (*handler) (struct ccw_device *, unsigned long, struct irb *);
 };
 
+/*
+ * Possible CIO actions triggered by the unit check handler.
+ */
+enum uc_todo {
+        UC_TODO_RETRY,
+        UC_TODO_RETRY_ON_NEW_PATH,
+        UC_TODO_STOP
+};
 
 /**
  * struct ccw driver - device driver for channel attached devices
@@ -107,6 +115,7 @@ struct ccw_device {
  * @freeze: callback for freezing during hibernation snapshotting
  * @thaw: undo work done in @freeze
  * @restore: callback for restoring after hibernation
+ * @uc_handler: callback for unit check handler
  * @driver: embedded device driver structure
  * @name: device driver name
  */
@@ -124,6 +133,7 @@ struct ccw_driver {
         int (*freeze)(struct ccw_device *);
         int (*thaw) (struct ccw_device *);
         int (*restore)(struct ccw_device *);
+        enum uc_todo (*uc_handler) (struct ccw_device *, struct irb *);
         struct device_driver driver;
         char *name;
 };