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authorYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 12:17:53 -0700
committerYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 15:44:42 -0700
commit9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch)
tree1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/include/linux/flex_array.h
parent98260f3884f4a202f9ca5eabed40b1354c489b29 (diff)
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/include/linux/flex_array.h')
-rw-r--r--kernel/include/linux/flex_array.h81
1 files changed, 81 insertions, 0 deletions
diff --git a/kernel/include/linux/flex_array.h b/kernel/include/linux/flex_array.h
new file mode 100644
index 000000000..b6efb0c64
--- /dev/null
+++ b/kernel/include/linux/flex_array.h
@@ -0,0 +1,81 @@
+#ifndef _FLEX_ARRAY_H
+#define _FLEX_ARRAY_H
+
+#include <linux/types.h>
+#include <linux/reciprocal_div.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;
+ int elems_per_part;
+ struct reciprocal_value reciprocal_elems;
+ struct flex_array_part *parts[];
+ };
+ /*
+ * This little trick makes sure that
+ * sizeof(flex_array) == PAGE_SIZE
+ */
+ char padding[FLEX_ARRAY_BASE_SIZE];
+ };
+};
+
+/* Number of bytes left in base struct flex_array, excluding metadata */
+#define FLEX_ARRAY_BASE_BYTES_LEFT \
+ (FLEX_ARRAY_BASE_SIZE - offsetof(struct flex_array, parts))
+
+/* Number of pointers in base to struct flex_array_part pages */
+#define FLEX_ARRAY_NR_BASE_PTRS \
+ (FLEX_ARRAY_BASE_BYTES_LEFT / sizeof(struct flex_array_part *))
+
+/* Number of elements of size that fit in struct flex_array_part */
+#define FLEX_ARRAY_ELEMENTS_PER_PART(size) \
+ (FLEX_ARRAY_PART_SIZE / size)
+
+/*
+ * Defines a statically allocated flex array and ensures its parameters are
+ * valid.
+ */
+#define DEFINE_FLEX_ARRAY(__arrayname, __element_size, __total) \
+ struct flex_array __arrayname = { { { \
+ .element_size = (__element_size), \
+ .total_nr_elements = (__total), \
+ } } }; \
+ static inline void __arrayname##_invalid_parameter(void) \
+ { \
+ BUILD_BUG_ON((__total) > FLEX_ARRAY_NR_BASE_PTRS * \
+ FLEX_ARRAY_ELEMENTS_PER_PART(__element_size)); \
+ }
+
+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 nr_elements, 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);
+int flex_array_clear(struct flex_array *fa, unsigned int element_nr);
+void *flex_array_get(struct flex_array *fa, unsigned int element_nr);
+int flex_array_shrink(struct flex_array *fa);
+
+#define flex_array_put_ptr(fa, nr, src, gfp) \
+ flex_array_put(fa, nr, (void *)&(src), gfp)
+
+void *flex_array_get_ptr(struct flex_array *fa, unsigned int element_nr);
+
+#endif /* _FLEX_ARRAY_H */