f2fs: use crc and cp version to determine roll-forward recovery
Previously, we used cp_version only to detect recoverable dnodes.
In order to avoid same garbage cp_version, we needed to truncate the next
dnode during checkpoint, resulting in additional discard or data write.
If we can distinguish this by using crc in addition to cp_version, we can
remove this overhead.
There is backward compatibility concern where it changes node_footer layout.
So, this patch introduces a new checkpoint flag, CP_CRC_RECOVERY_FLAG, to
detect new layout. New layout will be activated only when this flag is set.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
diff --git a/fs/f2fs/node.h b/fs/f2fs/node.h
index fc76845..e8ca64a 100644
--- a/fs/f2fs/node.h
+++ b/fs/f2fs/node.h
@@ -229,6 +229,37 @@
f2fs_change_bit(block_off, nm_i->nat_bitmap);
}
+static inline nid_t ino_of_node(struct page *node_page)
+{
+ struct f2fs_node *rn = F2FS_NODE(node_page);
+ return le32_to_cpu(rn->footer.ino);
+}
+
+static inline nid_t nid_of_node(struct page *node_page)
+{
+ struct f2fs_node *rn = F2FS_NODE(node_page);
+ return le32_to_cpu(rn->footer.nid);
+}
+
+static inline unsigned int ofs_of_node(struct page *node_page)
+{
+ struct f2fs_node *rn = F2FS_NODE(node_page);
+ unsigned flag = le32_to_cpu(rn->footer.flag);
+ return flag >> OFFSET_BIT_SHIFT;
+}
+
+static inline __u64 cpver_of_node(struct page *node_page)
+{
+ struct f2fs_node *rn = F2FS_NODE(node_page);
+ return le64_to_cpu(rn->footer.cp_ver);
+}
+
+static inline block_t next_blkaddr_of_node(struct page *node_page)
+{
+ struct f2fs_node *rn = F2FS_NODE(node_page);
+ return le32_to_cpu(rn->footer.next_blkaddr);
+}
+
static inline void fill_node_footer(struct page *page, nid_t nid,
nid_t ino, unsigned int ofs, bool reset)
{
@@ -259,40 +290,30 @@
{
struct f2fs_checkpoint *ckpt = F2FS_CKPT(F2FS_P_SB(page));
struct f2fs_node *rn = F2FS_NODE(page);
+ size_t crc_offset = le32_to_cpu(ckpt->checksum_offset);
+ __u64 cp_ver = le64_to_cpu(ckpt->checkpoint_ver);
- rn->footer.cp_ver = ckpt->checkpoint_ver;
+ if (is_set_ckpt_flags(ckpt, CP_CRC_RECOVERY_FLAG)) {
+ __u64 crc = le32_to_cpu(*((__le32 *)
+ ((unsigned char *)ckpt + crc_offset)));
+ cp_ver |= (crc << 32);
+ }
+ rn->footer.cp_ver = cpu_to_le64(cp_ver);
rn->footer.next_blkaddr = cpu_to_le32(blkaddr);
}
-static inline nid_t ino_of_node(struct page *node_page)
+static inline bool is_recoverable_dnode(struct page *page)
{
- struct f2fs_node *rn = F2FS_NODE(node_page);
- return le32_to_cpu(rn->footer.ino);
-}
+ struct f2fs_checkpoint *ckpt = F2FS_CKPT(F2FS_P_SB(page));
+ size_t crc_offset = le32_to_cpu(ckpt->checksum_offset);
+ __u64 cp_ver = cur_cp_version(ckpt);
-static inline nid_t nid_of_node(struct page *node_page)
-{
- struct f2fs_node *rn = F2FS_NODE(node_page);
- return le32_to_cpu(rn->footer.nid);
-}
-
-static inline unsigned int ofs_of_node(struct page *node_page)
-{
- struct f2fs_node *rn = F2FS_NODE(node_page);
- unsigned flag = le32_to_cpu(rn->footer.flag);
- return flag >> OFFSET_BIT_SHIFT;
-}
-
-static inline unsigned long long cpver_of_node(struct page *node_page)
-{
- struct f2fs_node *rn = F2FS_NODE(node_page);
- return le64_to_cpu(rn->footer.cp_ver);
-}
-
-static inline block_t next_blkaddr_of_node(struct page *node_page)
-{
- struct f2fs_node *rn = F2FS_NODE(node_page);
- return le32_to_cpu(rn->footer.next_blkaddr);
+ if (is_set_ckpt_flags(ckpt, CP_CRC_RECOVERY_FLAG)) {
+ __u64 crc = le32_to_cpu(*((__le32 *)
+ ((unsigned char *)ckpt + crc_offset)));
+ cp_ver |= (crc << 32);
+ }
+ return cpu_to_le64(cp_ver) == cpver_of_node(page);
}
/*