summaryrefslogtreecommitdiffstats
path: root/include/linux/flex_array.h
diff options
context:
space:
mode:
authorIngo Molnar <mingo@elte.hu>2009-09-04 14:44:16 +0200
committerIngo Molnar <mingo@elte.hu>2009-09-04 14:44:16 +0200
commit695a461296e5df148c99ac087b9e1cb380f4db15 (patch)
tree951893036fdc0b7bae0e17bc739ac8ffe909781d /include/linux/flex_array.h
parentc7084b35eb1a4d3353a501508baf9d3d82822c93 (diff)
parent2b681fafcc50fea6304ed418667c9d04282acb73 (diff)
Merge branch 'amd-iommu/2.6.32' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/linux-2.6-iommu into core/iommu
Diffstat (limited to 'include/linux/flex_array.h')
-rw-r--r--include/linux/flex_array.h49
1 files changed, 49 insertions, 0 deletions
diff --git a/include/linux/flex_array.h b/include/linux/flex_array.h
new file mode 100644
index 00000000000..45ff1849151
--- /dev/null
+++ b/include/linux/flex_array.h
@@ -0,0 +1,49 @@
+#ifndef _FLEX_ARRAY_H
+#define _FLEX_ARRAY_H
+
+#include <linux/types.h>
+#include <asm/page.h>
+
+#define FLEX_ARRAY_PART_SIZE PAGE_SIZE
+#define FLEX_ARRAY_BASE_SIZE PAGE_SIZE
+
+struct flex_array_part;
+
+/*
+ * This is meant to replace cases where an array-like
+ * structure has gotten too big to fit into kmalloc()
+ * and the developer is getting tempted to use
+ * vmalloc().
+ */
+
+struct flex_array {
+ union {
+ struct {
+ int element_size;
+ int total_nr_elements;
+ struct flex_array_part *parts[];
+ };
+ /*
+ * This little trick makes sure that
+ * sizeof(flex_array) == PAGE_SIZE
+ */
+ char padding[FLEX_ARRAY_BASE_SIZE];
+ };
+};
+
+#define FLEX_ARRAY_INIT(size, total) { { {\
+ .element_size = (size), \
+ .total_nr_elements = (total), \
+} } }
+
+struct flex_array *flex_array_alloc(int element_size, unsigned int total,
+ gfp_t flags);
+int flex_array_prealloc(struct flex_array *fa, unsigned int start,
+ unsigned int end, gfp_t flags);
+void flex_array_free(struct flex_array *fa);
+void flex_array_free_parts(struct flex_array *fa);
+int flex_array_put(struct flex_array *fa, unsigned int element_nr, void *src,
+ gfp_t flags);
+void *flex_array_get(struct flex_array *fa, unsigned int element_nr);
+
+#endif /* _FLEX_ARRAY_H */