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>
This commit is contained in:
Jaegeuk Kim
2016-09-19 17:55:10 -07:00
parent 5d4c0af41f
commit a468f0ef51
7 changed files with 63 additions and 100 deletions

View File

@@ -229,6 +229,37 @@ static inline void set_to_next_nat(struct f2fs_nm_info *nm_i, nid_t start_nid)
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 @@ static inline void fill_node_footer_blkaddr(struct page *page, block_t blkaddr)
{
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);
}
/*