diff options
| author | Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> | 2010-07-18 05:42:23 +0400 |
|---|---|---|
| committer | Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> | 2010-07-23 05:02:15 +0400 |
| commit | 26dfdd8e29f28c08aa67861b3c83d0f3f7d30cee (patch) | |
| tree | 3cc14a71010b454f6524006e973147837f040a39 /fs/nilfs2/btnode.c | |
| parent | f8e6cc013b896d75d6ce4ec9e168014af1257fd8 (diff) | |
| download | linux-26dfdd8e29f28c08aa67861b3c83d0f3f7d30cee.tar.xz | |
nilfs2: add read ahead mode to nilfs_btnode_submit_block
This adds mode argument to nilfs_btnode_submit_block() function and
allows it to issue a read-ahead request.
An optional submit_ptr argument is also added to store the actual
block address for which bio is sent. submit_ptr is used for a series
of read-ahead requests, and helps to decide if each requested block is
continous to the previous one on disk.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Diffstat (limited to 'fs/nilfs2/btnode.c')
| -rw-r--r-- | fs/nilfs2/btnode.c | 17 |
1 files changed, 14 insertions, 3 deletions
diff --git a/fs/nilfs2/btnode.c b/fs/nilfs2/btnode.c index 0a6834bb278e..f78ab1044d1d 100644 --- a/fs/nilfs2/btnode.c +++ b/fs/nilfs2/btnode.c @@ -96,7 +96,8 @@ nilfs_btnode_create_block(struct address_space *btnc, __u64 blocknr) } int nilfs_btnode_submit_block(struct address_space *btnc, __u64 blocknr, - sector_t pblocknr, struct buffer_head **pbh) + sector_t pblocknr, int mode, + struct buffer_head **pbh, sector_t *submit_ptr) { struct buffer_head *bh; struct inode *inode = NILFS_BTNC_I(btnc); @@ -127,7 +128,16 @@ int nilfs_btnode_submit_block(struct address_space *btnc, __u64 blocknr, } } } - lock_buffer(bh); + + if (mode == READA) { + if (pblocknr != *submit_ptr + 1 || !trylock_buffer(bh)) { + err = -EBUSY; /* internal code */ + brelse(bh); + goto out_locked; + } + } else { /* mode == READ */ + lock_buffer(bh); + } if (buffer_uptodate(bh)) { unlock_buffer(bh); err = -EEXIST; /* internal code */ @@ -138,8 +148,9 @@ int nilfs_btnode_submit_block(struct address_space *btnc, __u64 blocknr, bh->b_blocknr = pblocknr; /* set block address for read */ bh->b_end_io = end_buffer_read_sync; get_bh(bh); - submit_bh(READ, bh); + submit_bh(mode, bh); bh->b_blocknr = blocknr; /* set back to the given block address */ + *submit_ptr = pblocknr; err = 0; found: *pbh = bh; |