f2fs: enhance on-disk inode structure scalability
This patch add new flag F2FS_EXTRA_ATTR storing in inode.i_inline
to indicate that on-disk structure of current inode is extended.
In order to extend, we changed the inode structure a bit:
Original one:
struct f2fs_inode {
...
struct f2fs_extent i_ext;
__le32 i_addr[DEF_ADDRS_PER_INODE];
__le32 i_nid[DEF_NIDS_PER_INODE];
}
Extended one:
struct f2fs_inode {
...
struct f2fs_extent i_ext;
union {
struct {
__le16 i_extra_isize;
__le16 i_padding;
__le32 i_extra_end[0];
};
__le32 i_addr[DEF_ADDRS_PER_INODE];
};
__le32 i_nid[DEF_NIDS_PER_INODE];
}
Once F2FS_EXTRA_ATTR is set, we will steal four bytes in the head of
i_addr field for storing i_extra_isize and i_padding. with i_extra_isize,
we can calculate actual size of reserved space in i_addr, available
attribute fields included in total extra attribute fields for current
inode can be described as below:
+--------------------+
| .i_mode |
| ... |
| .i_ext |
+--------------------+
| .i_extra_isize |-----+
| .i_padding | |
| .i_prjid | |
| .i_atime_extra | |
| .i_ctime_extra | |
| .i_mtime_extra |<----+
| .i_inode_cs |<----- store blkaddr/inline from here
| .i_xattr_cs |
| ... |
+--------------------+
| |
| block address |
| |
+--------------------+
| .i_nid |
+--------------------+
| node_footer |
| (nid, ino, offset) |
+--------------------+
Hence, with this patch, we would enhance scalability of f2fs inode for
storing more newly added attribute.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c
index 5396611..547b84f 100644
--- a/fs/f2fs/node.c
+++ b/fs/f2fs/node.c
@@ -655,7 +655,8 @@
dn->nid = nids[level];
dn->ofs_in_node = offset[level];
dn->node_page = npage[level];
- dn->data_blkaddr = datablock_addr(dn->node_page, dn->ofs_in_node);
+ dn->data_blkaddr = datablock_addr(dn->inode,
+ dn->node_page, dn->ofs_in_node);
return 0;
release_pages:
@@ -2263,7 +2264,9 @@
dst->i_blocks = cpu_to_le64(1);
dst->i_links = cpu_to_le32(1);
dst->i_xattr_nid = 0;
- dst->i_inline = src->i_inline & F2FS_INLINE_XATTR;
+ dst->i_inline = src->i_inline & (F2FS_INLINE_XATTR | F2FS_EXTRA_ATTR);
+ if (dst->i_inline & F2FS_EXTRA_ATTR)
+ dst->i_extra_isize = src->i_extra_isize;
new_ni = old_ni;
new_ni.ino = ino;