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authorDaniel Vetter <daniel.vetter@ffwll.ch>2016-08-15 10:41:47 +0200
committerDaniel Vetter <daniel.vetter@ffwll.ch>2016-08-15 10:41:47 +0200
commitcc9263874b42bf98209dce0afe698b550648e770 (patch)
treef0eafd344c501e420de06c2e0f29f2ae0e6a9a1b /include/linux/ceph/string_table.h
parentdrm/i915: Unbind closed vma for i915_gem_object_unbind() (diff)
parentMerge tag 'drm-intel-next-2016-08-08' of git://anongit.freedesktop.org/drm-intel into drm-next (diff)
Merge remote-tracking branch 'airlied/drm-next' into drm-intel-next-queued
Backmerge because too many conflicts, and also we need to get at the latest struct fence patches from Gustavo. Requested by Chris Wilson. Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Diffstat (limited to 'include/linux/ceph/string_table.h')
-rw-r--r--include/linux/ceph/string_table.h62
1 files changed, 62 insertions, 0 deletions
diff --git a/include/linux/ceph/string_table.h b/include/linux/ceph/string_table.h
new file mode 100644
index 000000000000..1b02c96daf75
--- /dev/null
+++ b/include/linux/ceph/string_table.h
@@ -0,0 +1,62 @@
+#ifndef _FS_CEPH_STRING_TABLE_H
+#define _FS_CEPH_STRING_TABLE_H
+
+#include <linux/types.h>
+#include <linux/kref.h>
+#include <linux/rbtree.h>
+#include <linux/rcupdate.h>
+
+struct ceph_string {
+ struct kref kref;
+ union {
+ struct rb_node node;
+ struct rcu_head rcu;
+ };
+ size_t len;
+ char str[];
+};
+
+extern void ceph_release_string(struct kref *ref);
+extern struct ceph_string *ceph_find_or_create_string(const char *str,
+ size_t len);
+extern bool ceph_strings_empty(void);
+
+static inline struct ceph_string *ceph_get_string(struct ceph_string *str)
+{
+ kref_get(&str->kref);
+ return str;
+}
+
+static inline void ceph_put_string(struct ceph_string *str)
+{
+ if (!str)
+ return;
+ kref_put(&str->kref, ceph_release_string);
+}
+
+static inline int ceph_compare_string(struct ceph_string *cs,
+ const char* str, size_t len)
+{
+ size_t cs_len = cs ? cs->len : 0;
+ if (cs_len != len)
+ return cs_len - len;
+ if (len == 0)
+ return 0;
+ return strncmp(cs->str, str, len);
+}
+
+#define ceph_try_get_string(x) \
+({ \
+ struct ceph_string *___str; \
+ rcu_read_lock(); \
+ for (;;) { \
+ ___str = rcu_dereference(x); \
+ if (!___str || \
+ kref_get_unless_zero(&___str->kref)) \
+ break; \
+ } \
+ rcu_read_unlock(); \
+ (___str); \
+})
+
+#endif