[f2fs-dev][PATCH v2] f2fs: use ra_meta_pages to simplify readahead code in restore_node_summary

From: Chao Yu
Date: Wed Dec 17 2014 - 05:11:43 EST


Use more common function ra_meta_pages() with META_POR to readahead node blocks
in restore_node_summary() instead of ra_sum_pages(), hence we can simplify the
readahead code there, and also we can remove unused function ra_sum_pages().

changes from v1:
o fix one bug when using truncate_inode_pages_range which is pointed out by
Jaegeuk Kim.

Signed-off-by: Chao Yu <chao2.yu@xxxxxxxxxxx>
---
fs/f2fs/node.c | 68 +++++++++++++---------------------------------------------
1 file changed, 15 insertions(+), 53 deletions(-)

diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c
index 5aa54a0..ab48b4c 100644
--- a/fs/f2fs/node.c
+++ b/fs/f2fs/node.c
@@ -1726,80 +1726,42 @@ int recover_inode_page(struct f2fs_sb_info *sbi, struct page *page)
return 0;
}

-/*
- * ra_sum_pages() merge contiguous pages into one bio and submit.
- * these pre-read pages are allocated in bd_inode's mapping tree.
- */
-static int ra_sum_pages(struct f2fs_sb_info *sbi, struct page **pages,
- int start, int nrpages)
-{
- struct inode *inode = sbi->sb->s_bdev->bd_inode;
- struct address_space *mapping = inode->i_mapping;
- int i, page_idx = start;
- struct f2fs_io_info fio = {
- .type = META,
- .rw = READ_SYNC | REQ_META | REQ_PRIO
- };
-
- for (i = 0; page_idx < start + nrpages; page_idx++, i++) {
- /* alloc page in bd_inode for reading node summary info */
- pages[i] = grab_cache_page(mapping, page_idx);
- if (!pages[i])
- break;
- f2fs_submit_page_mbio(sbi, pages[i], page_idx, &fio);
- }
-
- f2fs_submit_merged_bio(sbi, META, READ);
- return i;
-}
-
int restore_node_summary(struct f2fs_sb_info *sbi,
unsigned int segno, struct f2fs_summary_block *sum)
{
struct f2fs_node *rn;
struct f2fs_summary *sum_entry;
- struct inode *inode = sbi->sb->s_bdev->bd_inode;
block_t addr;
int bio_blocks = MAX_BIO_BLOCKS(sbi);
- struct page *pages[bio_blocks];
- int i, idx, last_offset, nrpages, err = 0;
+ int i, idx, last_offset, nrpages;

/* scan the node segment */
last_offset = sbi->blocks_per_seg;
addr = START_BLOCK(sbi, segno);
sum_entry = &sum->entries[0];

- for (i = 0; !err && i < last_offset; i += nrpages, addr += nrpages) {
+ for (i = 0; i < last_offset; i += nrpages, addr += nrpages) {
nrpages = min(last_offset - i, bio_blocks);

/* readahead node pages */
- nrpages = ra_sum_pages(sbi, pages, addr, nrpages);
- if (!nrpages)
- return -ENOMEM;
+ ra_meta_pages(sbi, addr, nrpages, META_POR);

- for (idx = 0; idx < nrpages; idx++) {
- if (err)
- goto skip;
+ for (idx = addr; idx < addr + nrpages; idx++) {
+ struct page *page = get_meta_page(sbi, idx);

- lock_page(pages[idx]);
- if (unlikely(!PageUptodate(pages[idx]))) {
- err = -EIO;
- } else {
- rn = F2FS_NODE(pages[idx]);
- sum_entry->nid = rn->footer.nid;
- sum_entry->version = 0;
- sum_entry->ofs_in_node = 0;
- sum_entry++;
- }
- unlock_page(pages[idx]);
-skip:
- page_cache_release(pages[idx]);
+ rn = F2FS_NODE(page);
+ sum_entry->nid = rn->footer.nid;
+ sum_entry->version = 0;
+ sum_entry->ofs_in_node = 0;
+ sum_entry++;
+ f2fs_put_page(page, 1);
}

- invalidate_mapping_pages(inode->i_mapping, addr,
- addr + nrpages);
+ truncate_inode_pages_range(META_MAPPING(sbi),
+ addr << PAGE_CACHE_SHIFT,
+ ((addr + nrpages) << PAGE_CACHE_SHIFT) - 1);
}
- return err;
+ return 0;
}

static void remove_nats_in_journal(struct f2fs_sb_info *sbi)
--
2.1.2


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/