For better read performance, we add a new function to support for merging contiguous read as the one for write.
Signed-off-by: Chao Yu <chao2.yu@xxxxxxxxxxx>
---
fs/f2fs/data.c | 45 +++++++++++++++++++++++++++++++++++++++++++++
fs/f2fs/f2fs.h | 2 ++
2 files changed, 47 insertions(+)
diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index aa3438c..f30060b 100644
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -404,6 +404,51 @@ int f2fs_readpage(struct f2fs_sb_info *sbi, struct page *page,
return 0;
}
+void f2fs_submit_read_bio(struct f2fs_sb_info *sbi, int rw)
+{
+ down_read(&sbi->bio_sem);
+ if (sbi->read_bio) {
+ submit_bio(rw, sbi->read_bio);
+ sbi->read_bio = NULL;
+ }
+ up_read(&sbi->bio_sem);
+}
+
+void submit_read_page(struct f2fs_sb_info *sbi, struct page *page,
+ block_t blk_addr, int rw)
+{
+ struct block_device *bdev = sbi->sb->s_bdev;
+ int bio_blocks;
+
+ verify_block_addr(sbi, blk_addr);
+
+ down_read(&sbi->bio_sem);
+
+ if (sbi->read_bio && sbi->last_read_block != blk_addr - 1) {
+ submit_bio(rw, sbi->read_bio);
+ sbi->read_bio = NULL;
+ }
+
+alloc_new:
+ if (sbi->read_bio == NULL) {
+ bio_blocks = MAX_BIO_BLOCKS(max_hw_blocks(sbi));
+ sbi->read_bio = f2fs_bio_alloc(bdev, bio_blocks);
+ sbi->read_bio->bi_sector = SECTOR_FROM_BLOCK(sbi, blk_addr);
+ sbi->read_bio->bi_end_io = read_end_io;
+ }
+
+ if (bio_add_page(sbi->read_bio, page, PAGE_CACHE_SIZE, 0) <
+ PAGE_CACHE_SIZE) {
+ submit_bio(rw, sbi->read_bio);
+ sbi->read_bio = NULL;
+ goto alloc_new;
+ }
+
+ sbi->last_read_block = blk_addr;
+
+ up_read(&sbi->bio_sem);
+}
+
/*
* This function should be used by the data read flow only where it
* does not check the "create" flag that indicates block allocation.
diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 89dc750..0afdcec 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -359,6 +359,8 @@ struct f2fs_sb_info {
/* for segment-related operations */
struct f2fs_sm_info *sm_info; /* segment manager */
+ struct bio *read_bio; /* read bios to merge */
+ sector_t last_read_block; /* last read block number */
struct bio *bio[NR_PAGE_TYPE]; /* bios to merge */
sector_t last_block_in_bio[NR_PAGE_TYPE]; /* last block number */
struct rw_semaphore bio_sem; /* IO semaphore */
--
1.7.9.5
--
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