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.ryus...@lab.ntt.co.jp>
---
fs/nilfs2/btnode.c | 17 ++++++++++++++---
fs/nilfs2/btnode.h | 4 ++--
fs/nilfs2/btree.c | 3 ++-
fs/nilfs2/gcinode.c | 6 ++++--
4 files changed, 22 insertions(+), 8 deletions(-)
diff --git a/fs/nilfs2/btnode.c b/fs/nilfs2/btnode.c
index 0a6834b..f78ab10 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;
diff --git a/fs/nilfs2/btnode.h b/fs/nilfs2/btnode.h
index 07da83f..7903749 100644
--- a/fs/nilfs2/btnode.h
+++ b/fs/nilfs2/btnode.h
@@ -42,8 +42,8 @@ void nilfs_btnode_cache_init(struct address_space *, struct
backing_dev_info *);
void nilfs_btnode_cache_clear(struct address_space *);
struct buffer_head *nilfs_btnode_create_block(struct address_space *btnc,
__u64 blocknr);
-int nilfs_btnode_submit_block(struct address_space *, __u64, sector_t,
- struct buffer_head **);
+int nilfs_btnode_submit_block(struct address_space *, __u64, sector_t, int,
+ struct buffer_head **, sector_t *);
void nilfs_btnode_delete(struct buffer_head *);
int nilfs_btnode_prepare_change_key(struct address_space *,
struct nilfs_btnode_chkey_ctxt *);
diff --git a/fs/nilfs2/btree.c b/fs/nilfs2/btree.c
index 6462c70..4669389 100644
--- a/fs/nilfs2/btree.c
+++ b/fs/nilfs2/btree.c
@@ -71,9 +71,10 @@ static int nilfs_btree_get_block(const struct nilfs_bmap
*btree, __u64 ptr,
{
struct address_space *btnc = &NILFS_BMAP_I(btree)->i_btnode_cache;
struct buffer_head *bh;
+ sector_t pbn = 0;
int err;
- err = nilfs_btnode_submit_block(btnc, ptr, 0, bhp);
+ err = nilfs_btnode_submit_block(btnc, ptr, pbn, READ, bhp, &pbn);
if (err)
return err == -EEXIST ? 0 : err;
diff --git a/fs/nilfs2/gcinode.c b/fs/nilfs2/gcinode.c
index b634382..bed3a78 100644
--- a/fs/nilfs2/gcinode.c
+++ b/fs/nilfs2/gcinode.c
@@ -151,8 +151,10 @@ int nilfs_gccache_submit_read_data(struct inode *inode,
sector_t blkoff,
int nilfs_gccache_submit_read_node(struct inode *inode, sector_t pbn,
__u64 vbn, struct buffer_head **out_bh)
{
- int ret = nilfs_btnode_submit_block(&NILFS_I(inode)->i_btnode_cache,
- vbn ? : pbn, pbn, out_bh);
+ int ret;
+
+ ret = nilfs_btnode_submit_block(&NILFS_I(inode)->i_btnode_cache,
+ vbn ? : pbn, pbn, READ, out_bh, &pbn);
if (ret == -EEXIST) /* internal code (cache hit) */
ret = 0;
return ret;
--
1.6.6.2
--
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