core: add cset_busy helpers

This avoid driver developer to handle with cset flags and locking. It also simplify the driver code. set and clear helpers can be locked; the 'if' statement doesn't slow down the code because the compiler will remove it according to the function argument (only if you pass static value) Signed-off-by: Federico Vaga <federico.vaga@cern.ch> Acked-by: Alessandro Rubini <rubini@gnudd.com>

core: add cset_busy helpers
This avoid driver developer to handle with cset flags and locking. It also simplify the driver code. set and clear helpers can be locked; the 'if' statement doesn't slow down the code because the compiler will remove it according to the function argument (only if you pass static value) Signed-off-by: Federico Vaga <federico.vaga@cern.ch> Acked-by: Alessandro Rubini <rubini@gnudd.com>
14923d2d · Federico Vaga · Federico Vaga · e926a4cb · 14923d2d
Commit 14923d2d authored Sep 23, 2014 by Federico Vaga Committed by Federico Vaga Mar 03, 2015
Hide whitespace changes
Inline Side-by-side

Showing with 45 additions and 1 deletion

zio.h include/linux/zio.h +45 -1

No files found.
--- a/include/linux/zio.h
+++ b/include/linux/zio.h
@@ -20,6 +20,7 @@
 #include <linux/cdev.h>
 #include <linux/list.h>
 #include <linux/string.h>
+#include <linux/spinlock.h>

 #include <linux/zio-sysfs.h>

@@ -301,6 +302,50 @@ struct zio_block {
 	size_t			uoff;
 };

+
+/**
+ * Mark the cset as 'busy'
+ * @param cset the cset to set busy
+ * @param locked '1' if you want to protect the operatio, '0' if you will
+ *               protect the operation by yourself
+ */
+static inline void zio_cset_busy_set(struct zio_cset *cset, int locked)
+{
+	unsigned long flags;
+
+	if (locked)
+		spin_lock_irqsave(&cset->lock, flags);
+	cset->flags |= ZIO_CSET_HW_BUSY;
+	if (locked)
+		spin_unlock_irqrestore(&cset->lock, flags);
+}
+
+/**
+ * Mark the cset as 'not busy'
+ * @param cset the cset to set busy
+ * @param locked '1' if you want to protect the operatio, '0' if you will
+ *               protect the operation by yourself
+ */
+static inline void zio_cset_busy_clear(struct zio_cset *cset, int locked)
+{
+	unsigned long flags;
+
+	if (locked)
+		spin_lock_irqsave(&cset->lock, flags);
+	cset->flags &= ~ZIO_CSET_HW_BUSY;
+	if (locked)
+		spin_unlock_irqrestore(&cset->lock, flags);
+}
+
+/**
+ * Check if the cset is marked as 'busy'
+ * @param cset the cset to check
+ */
+static inline int zio_cset_is_busy(struct zio_cset *cset)
+{
+	return !!(cset->flags & ZIO_CSET_HW_BUSY);
+}
+
 /*
 * We must know whether the ctrl block has been filled/read or not: "cdone"
 * No "set_ctrl" or "clr_cdone" are needed, as cdone starts 0 and is only set
@@ -337,6 +382,5 @@ void zio_ffa_free_s(struct zio_ffa *ffa, unsigned long addr, size_t size);
 void zio_ffa_dump(struct zio_ffa *ffa); /* diagnostics */
 void zio_ffa_reset(struct zio_ffa *ffa);

-
 #endif /* __KERNEL__ */
 #endif /* __ZIO_H__ */