From: Vyacheslav Dubeyko <slava@xxxxxxxxxxx>
Subject: [RFC][PATCH 03/15] nilfs2: introduce xanode's key related declarations
This patch adds declaration of structures, macros and auxiliary
functions for xanode's keys processing.
Signed-off-by: Vyacheslav Dubeyko <slava@xxxxxxxxxxx>
CC: Ryusuke Konishi <konishi.ryusuke@xxxxxxxxxxxxx>
---
fs/nilfs2/xafile.h | 184 ++++++++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 184 insertions(+)
diff --git a/fs/nilfs2/xafile.h b/fs/nilfs2/xafile.h
index 28faa1f..34e4bb9 100644
--- a/fs/nilfs2/xafile.h
+++ b/fs/nilfs2/xafile.h
@@ -71,6 +71,82 @@ union nilfs_xanode_header {
struct nilfs_tree_xanode_header tree_hdr;
};
+/* Key types */
+#define NILFS_UNKNOWN_KEY_TYPE 0
+/* Temporary, numbers from 1 till 4 are simply reserved */
+#define NILFS_XATTR_TREE_INDEX_KEY_TYPE 5
+#define NILFS_XATTR_TREE_LEAF_KEY_TYPE 6
+#define NILFS_XATTR_KEY_TYPE_MASK 0xF
+
+/* Key's flags*/
+#define NILFS_XATTR_KEY_FLAG_MASK 0xFFF0
+
+/*
+ * struct nilfs_xattr_name_hash - complex hash of xattr's name
+ * @name_len: length of the name
+ * @name_index: index of prefix of xattr's name
+ * @first_symbol: first symbol after first full stop
+ * @last_symbol: last symbol of xattr's name
+ * @hash: calculated hash of xattr's name (for example, jhash)
+ */
+struct nilfs_xattr_name_hash {
+ u8 name_len;
+ u8 name_index;
+ u8 first_symbol;
+ u8 last_symbol;
+ __le32 hash;
+} __packed;
+
+/*
+ * struct nilfs_xattr_value_hash - complex hash of xattr's value
+ * @value_len: length of the value
+ * @first_byte: first byte of value
+ * @last_byte: last byte of value
+ * @hash: calculated hash of xattr's value (for example, jhash)
+ */
+struct nilfs_xattr_value_hash {
+ __le16 value_len;
+ u8 first_byte;
+ u8 last_byte;
+ __le32 hash;
+} __packed;
+
+/*
+ * struct nilfs_xattr_common_key - common xattr key for xanode
+ * @flags: key's flags
+ * @entry_offset: entry offset inside the node
+ * @name_hash: complex hash of xattr's name
+ * @entry_size: size of entry in bytes
+ * @padding: padding field
+ */
+struct nilfs_xattr_common_key {
+ __le16 flags;
+ __le16 entry_offset;
+ struct nilfs_xattr_name_hash name_hash;
+ __le16 entry_size;
+ __le16 padding;
+} __packed;
+
+/*
+ * struct nilfs_xattr_index_key - xattr index key
+ * @name_hash: complex hash of xattr's name
+ * @leaf: leaf node ID
+ */
+struct nilfs_xattr_index_key {
+ struct nilfs_xattr_name_hash name_hash;
+ __le64 leaf;
+} __packed;
+
+/*
+ * struct nilfs_xattr_leaf_key - xattr leaf key
+ */
+typedef struct nilfs_xattr_common_key nilfs_xattr_leaf_key;
+
+union nilfs_xattr_key {
+ __le16 flags;
+ nilfs_xattr_leaf_key leaf_key;
+};
+
/* Xanode related declarations */
#define BH_DATA(bh) \
((char *)(((struct buffer_head *)(bh))->b_data))
@@ -136,4 +212,112 @@ void NILFS_XANODE_ADD_ENTRIES(__u16 val, union nilfs_xanode_header *hdr_ptr)
BUG();
}
+/* Key related declarations*/
+#define NILFS_XANODE_KEY(ptr) \
+ ((union nilfs_xattr_key *)(ptr))
+#define NILFS_XANODE_KEY_TYPE(key) \
+ (le16_to_cpu(NILFS_XANODE_KEY(key)->flags) & \
+ NILFS_XATTR_KEY_TYPE_MASK)
+#define NILFS_XANODE_KEY_FLAGS(key) \
+ (le16_to_cpu(NILFS_XANODE_KEY(key)->flags) & \
+ NILFS_XATTR_KEY_FLAG_MASK)
+#define NILFS_XANODE_KEY_SET_TYPE(type, key) \
+ (NILFS_XANODE_KEY(key)->flags = \
+ cpu_to_le16(NILFS_XANODE_KEY_FLAGS(key) | \
+ ((u16)type & NILFS_XATTR_KEY_TYPE_MASK)))
+#define NILFS_XANODE_KEY_SET_FLAGS(flags, key) \
+ (NILFS_XANODE_KEY(key)->flags = \
+ cpu_to_le16((u16)flags & NILFS_XANODE_KEY_TYPE(key)))
+
+#define NILFS_XANODE_END_KEY(hdr_ptr) \
+ ((__u32 *)((char *)(hdr_ptr) + \
+ NILFS_XANODE_HDR_SIZE(hdr_ptr) + \
+ NILFS_XANODE_INDEX_KEYS_SIZE(hdr_ptr) + \
+ (NILFS_XANODE_NOT_INDEX_KEY_SIZE(hdr_ptr) * \
+ NILFS_XANODE_ENTRIES(hdr_ptr))))
+
+#define NILFS_XANODE_END_KEY_VALUE 0
+#define NILFS_XANODE_END_KEY_SIZE sizeof(__u32)
+#define IS_END_KEY(key) (*(__u32 *)(key) == NILFS_XANODE_END_KEY_VALUE)
+
+#define NILFS_XANODE_INDEX_KEY(ptr) \
+ ((struct nilfs_xattr_index_key *)(ptr))
+#define NILFS_XANODE_LEAF_KEY(ptr) \
+ ((nilfs_xattr_leaf_key *)(ptr))
+
+static inline
+union nilfs_xattr_key *NEXT_KEY(union nilfs_xattr_key *key, int count)
+{
+ switch (NILFS_XANODE_KEY_TYPE(key)) {
+ case NILFS_XATTR_TREE_LEAF_KEY_TYPE:
+ return NILFS_XANODE_KEY(NILFS_XANODE_LEAF_KEY(key) + count);
+ };
+ BUG();
+}
+
+static inline
+union nilfs_xattr_key *PREV_KEY(union nilfs_xattr_key *key, int count)
+{
+ switch (NILFS_XANODE_KEY_TYPE(key)) {
+ case NILFS_XATTR_TREE_LEAF_KEY_TYPE:
+ return NILFS_XANODE_KEY(NILFS_XANODE_LEAF_KEY(key) - count);
+ };
+ BUG();
+}
+
+#define NILFS_XANODE_INDEX_KEYS_SIZE(hdr_ptr) \
+ (NILFS_XANODE_HDR(hdr_ptr)->tree_hdr.log_index_keys == 0 ? 0 : \
+ ((1 << NILFS_XANODE_HDR(hdr_ptr)->tree_hdr.log_index_keys) * \
+ sizeof(struct nilfs_xattr_index_key)))
+
+static inline
+size_t NILFS_XANODE_NOT_INDEX_KEY_SIZE(union nilfs_xanode_header *hdr_ptr)
+{
+ switch (NILFS_XANODE_TYPE(hdr_ptr)) {
+ case NILFS_XATTR_TREE_XANODE_TYPE:
+ return sizeof(nilfs_xattr_leaf_key);
+ };
+ BUG();
+}
+
+#define NILFS_XANODE_FIRST_INDEX_KEY(hdr_ptr) \
+ (NILFS_XANODE_INDEX_KEY((char *)(hdr_ptr) + \
+ NILFS_XANODE_HDR_SIZE(hdr_ptr)))
+#define NILFS_XANODE_FIRST_LEAF_KEY(hdr_ptr) \
+ (NILFS_XANODE_LEAF_KEY((char *)NILFS_XANODE_FIRST_INDEX_KEY(hdr_ptr) + \
+ NILFS_XANODE_INDEX_KEYS_SIZE(hdr_ptr)))
+
+static inline
+nilfs_xattr_leaf_key *
+NILFS_XANODE_LAST_LEAF_KEY(union nilfs_xanode_header *hdr_ptr)
+{
+ if (NILFS_XANODE_ENTRIES(hdr_ptr) == 0)
+ return NILFS_XANODE_LEAF_KEY(NILFS_XANODE_END_KEY(hdr_ptr));
+
+ return NILFS_XANODE_FIRST_LEAF_KEY(hdr_ptr) +
+ (NILFS_XANODE_ENTRIES(hdr_ptr) - 1);
+}
+
+static inline
+union nilfs_xattr_key *
+NILFS_XANODE_FIRST_NOT_INDEX_KEY(union nilfs_xanode_header *hdr_ptr)
+{
+ switch (NILFS_XANODE_TYPE(hdr_ptr)) {
+ case NILFS_XATTR_TREE_XANODE_TYPE:
+ return NILFS_XANODE_KEY(NILFS_XANODE_FIRST_LEAF_KEY(hdr_ptr));
+ };
+ BUG();
+}
+
+static inline
+union nilfs_xattr_key *
+NILFS_XANODE_LAST_NOT_INDEX_KEY(union nilfs_xanode_header *hdr_ptr)
+{
+ switch (NILFS_XANODE_TYPE(hdr_ptr)) {
+ case NILFS_XATTR_TREE_XANODE_TYPE:
+ return NILFS_XANODE_KEY(NILFS_XANODE_LAST_LEAF_KEY(hdr_ptr));
+ };
+ BUG();
+}
+
#endif /* _NILFS_XAFILE_H */
--
1.7.9.5
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