f2fs: remove the ugly pointer conversion

This patch modifies the use of bi_private to remove pointer chasing for sbi.
Previously, we had a bi_private structure, but it needs memory allocation.
So this patch uses bi_private by the sbi pointer and adds a completion pointer
into the sbi.
This can achieve no memory allocation and nice use of the bi_private.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>

diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index 20c3c64..d175ae3 100644 (file)
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -45,7 +45,7 @@ static void f2fs_read_end_io(struct bio *bio, int err)
 
 static void f2fs_write_end_io(struct bio *bio, int err)
 {
-       struct f2fs_sb_info *sbi = F2FS_SB(bio->bi_io_vec->bv_page->mapping->host->i_sb);
+       struct f2fs_sb_info *sbi = bio->bi_private;
        struct bio_vec *bvec;
        int i;
 
@@ -61,8 +61,10 @@ static void f2fs_write_end_io(struct bio *bio, int err)
                dec_page_count(sbi, F2FS_WRITEBACK);
        }
 
-       if (bio->bi_private)
-               complete(bio->bi_private);
+       if (sbi->wait_io) {
+               complete(sbi->wait_io);
+               sbi->wait_io = NULL;
+       }
 
        if (!get_pages(sbi, F2FS_WRITEBACK) &&
                        !list_empty(&sbi->cp_wait.task_list))
@@ -85,6 +87,7 @@ static struct bio *__bio_alloc(struct f2fs_sb_info *sbi, block_t blk_addr,
        bio->bi_bdev = sbi->sb->s_bdev;
        bio->bi_iter.bi_sector = SECTOR_FROM_BLOCK(sbi, blk_addr);
        bio->bi_end_io = is_read ? f2fs_read_end_io : f2fs_write_end_io;
+       bio->bi_private = sbi;
 
        return bio;
 }
@@ -112,7 +115,7 @@ static void __submit_merged_bio(struct f2fs_bio_info *io)
                 */
                if (fio->type == META_FLUSH) {
                        DECLARE_COMPLETION_ONSTACK(wait);
-                       io->bio->bi_private = &wait;
+                       io->sbi->wait_io = &wait;
                        submit_bio(rw, io->bio);
                        wait_for_completion(&wait);
                } else {

diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 55288d2..aeff132 100644 (file)
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -398,6 +398,7 @@ struct f2fs_sb_info {
        /* for bio operations */
        struct f2fs_bio_info read_io;                   /* for read bios */
        struct f2fs_bio_info write_io[NR_PAGE_TYPE];    /* for write bios */
+       struct completion *wait_io;             /* for completion bios */
 
        /* for checkpoint */
        struct f2fs_checkpoint *ckpt;           /* raw checkpoint pointer */