Changeset 1d8cdb1 in mainline for uspace/lib/libblock/libblock.h

Timestamp:

2008-11-18T20:28:17Z (16 years ago)

Author:

Jakub Jermar <jakub@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

18c485a

Parents:

26fa0f9f

Message:

Avoid unnecessary block reads in block_get().

File:

• uspace/lib/libblock/libblock.h (modified) (2 diffs)

uspace/lib/libblock/libblock.h

@@ -45 +45 @@
 #include <libadt/list.h>
 
+/*
+ * Flags that can be used with block_get().
+ */
+
+/** 
+ * This macro is a symbolic value for situations where no special flags are
+ * needed.
+ */
+#define BLOCK_FLAGS_NONE        0
+
+/**
+ * When the client of block_get() intends to overwrite the current contents of
+ * the block, this flag is used to avoid the unnecessary read.
+ */
+#define BLOCK_FLAGS_NOREAD      1
+
 typedef unsigned bn_t;  /**< Block number type. */
 
@@ -78 +94 @@
 extern int block_cache_init(dev_handle_t, size_t, unsigned);
 
-extern block_t *block_get(dev_handle_t, bn_t);
+extern block_t *block_get(dev_handle_t, bn_t, int flags);
 extern void block_put(block_t *);