f2fs: introduce __get_node_page to reuse common code

There are duplicated code in between get_node_page and get_node_page_ra,
introduce __get_node_page to includes common parts of these two, and
export get_node_page and get_node_page_ra by reusing __get_node_page.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c
index c1ddf3d88dd99dc91517a7c5d8ab51e92faccc30..5a2d800f4abca95870f5f470323e457aff258002 100644 (file)
--- a/fs/f2fs/node.c
+++ b/fs/f2fs/node.c
@@ -1060,56 +1060,35 @@ void ra_node_page(struct f2fs_sb_info *sbi, nid_t nid)
        f2fs_put_page(apage, err ? 1 : 0);
 }
 
-struct page *get_node_page(struct f2fs_sb_info *sbi, pgoff_t nid)
+/*
+ * readahead MAX_RA_NODE number of node pages.
+ */
+void ra_node_pages(struct page *parent, int start)
 {
-       struct page *page;
-       int err;
+       struct f2fs_sb_info *sbi = F2FS_P_SB(parent);
+       struct blk_plug plug;
+       int i, end;
+       nid_t nid;
 
-       if (!nid)
-               return ERR_PTR(-ENOENT);
-       f2fs_bug_on(sbi, check_nid_range(sbi, nid));
-repeat:
-       page = grab_cache_page(NODE_MAPPING(sbi), nid);
-       if (!page)
-               return ERR_PTR(-ENOMEM);
+       blk_start_plug(&plug);
 
-       err = read_node_page(page, READ_SYNC);
-       if (err < 0) {
-               f2fs_put_page(page, 1);
-               return ERR_PTR(err);
-       } else if (err == LOCKED_PAGE) {
-               goto page_hit;
+       /* Then, try readahead for siblings of the desired node */
+       end = start + MAX_RA_NODE;
+       end = min(end, NIDS_PER_BLOCK);
+       for (i = start; i < end; i++) {
+               nid = get_nid(parent, i, false);
+               ra_node_page(sbi, nid);
        }
 
-       lock_page(page);
-
-       if (unlikely(!PageUptodate(page))) {
-               f2fs_put_page(page, 1);
-               return ERR_PTR(-EIO);
-       }
-       if (unlikely(page->mapping != NODE_MAPPING(sbi))) {
-               f2fs_put_page(page, 1);
-               goto repeat;
-       }
-page_hit:
-       f2fs_bug_on(sbi, nid != nid_of_node(page));
-       return page;
+       blk_finish_plug(&plug);
 }
 
-/*
- * Return a locked page for the desired node page.
- * And, readahead MAX_RA_NODE number of node pages.
- */
-struct page *get_node_page_ra(struct page *parent, int start)
+struct page *__get_node_page(struct f2fs_sb_info *sbi, pgoff_t nid,
+                                       struct page *parent, int start)
 {
-       struct f2fs_sb_info *sbi = F2FS_P_SB(parent);
-       struct blk_plug plug;
        struct page *page;
-       int err, i, end;
-       nid_t nid;
+       int err;
 
-       /* First, try getting the desired direct node. */
-       nid = get_nid(parent, start, false);
        if (!nid)
                return ERR_PTR(-ENOENT);
        f2fs_bug_on(sbi, check_nid_range(sbi, nid));
@@ -1126,21 +1105,11 @@ repeat:
                goto page_hit;
        }
 
-       blk_start_plug(&plug);
-
-       /* Then, try readahead for siblings of the desired node */
-       end = start + MAX_RA_NODE;
-       end = min(end, NIDS_PER_BLOCK);
-       for (i = start + 1; i < end; i++) {
-               nid_t tnid;
-
-               tnid = get_nid(parent, i, false);
-               ra_node_page(sbi, tnid);
-       }
-
-       blk_finish_plug(&plug);
+       if (parent)
+               ra_node_pages(parent, start + 1);
 
        lock_page(page);
+
        if (unlikely(!PageUptodate(page))) {
                f2fs_put_page(page, 1);
                return ERR_PTR(-EIO);
@@ -1154,6 +1123,19 @@ page_hit:
        return page;
 }
 
+struct page *get_node_page(struct f2fs_sb_info *sbi, pgoff_t nid)
+{
+       return __get_node_page(sbi, nid, NULL, 0);
+}
+
+struct page *get_node_page_ra(struct page *parent, int start)
+{
+       struct f2fs_sb_info *sbi = F2FS_P_SB(parent);
+       nid_t nid = get_nid(parent, start, false);
+
+       return __get_node_page(sbi, nid, parent, start);
+}
+
 void sync_inode_page(struct dnode_of_data *dn)
 {
        if (IS_INODE(dn->node_page) || dn->inode_page == dn->node_page) {