nilfs2: insert cache operation in palloc get block routines
This implements cache operation in get block routines of palloc code:
nilfs_palloc_get_desc_block(), nilfs_palloc_get_bitmap_block(), and
nilfs_palloc_get_entry_block().
This will complete the palloc cache.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
diff --git a/fs/nilfs2/alloc.c b/fs/nilfs2/alloc.c
index c56300d..3f959f1 100644
--- a/fs/nilfs2/alloc.c
+++ b/fs/nilfs2/alloc.c
@@ -142,29 +142,75 @@
}
}
+static int nilfs_palloc_get_block(struct inode *inode, unsigned long blkoff,
+ int create,
+ void (*init_block)(struct inode *,
+ struct buffer_head *,
+ void *),
+ struct buffer_head **bhp,
+ struct nilfs_bh_assoc *prev,
+ spinlock_t *lock)
+{
+ int ret;
+
+ spin_lock(lock);
+ if (prev->bh && blkoff == prev->blkoff) {
+ get_bh(prev->bh);
+ *bhp = prev->bh;
+ spin_unlock(lock);
+ return 0;
+ }
+ spin_unlock(lock);
+
+ ret = nilfs_mdt_get_block(inode, blkoff, create, init_block, bhp);
+ if (!ret) {
+ spin_lock(lock);
+ /*
+ * The following code must be safe for change of the
+ * cache contents during the get block call.
+ */
+ brelse(prev->bh);
+ get_bh(*bhp);
+ prev->bh = *bhp;
+ prev->blkoff = blkoff;
+ spin_unlock(lock);
+ }
+ return ret;
+}
+
static int nilfs_palloc_get_desc_block(struct inode *inode,
unsigned long group,
int create, struct buffer_head **bhp)
{
- return nilfs_mdt_get_block(inode,
- nilfs_palloc_desc_blkoff(inode, group),
- create, nilfs_palloc_desc_block_init, bhp);
+ struct nilfs_palloc_cache *cache = NILFS_MDT(inode)->mi_palloc_cache;
+
+ return nilfs_palloc_get_block(inode,
+ nilfs_palloc_desc_blkoff(inode, group),
+ create, nilfs_palloc_desc_block_init,
+ bhp, &cache->prev_desc, &cache->lock);
}
static int nilfs_palloc_get_bitmap_block(struct inode *inode,
unsigned long group,
int create, struct buffer_head **bhp)
{
- return nilfs_mdt_get_block(inode,
- nilfs_palloc_bitmap_blkoff(inode, group),
- create, NULL, bhp);
+ struct nilfs_palloc_cache *cache = NILFS_MDT(inode)->mi_palloc_cache;
+
+ return nilfs_palloc_get_block(inode,
+ nilfs_palloc_bitmap_blkoff(inode, group),
+ create, NULL, bhp,
+ &cache->prev_bitmap, &cache->lock);
}
int nilfs_palloc_get_entry_block(struct inode *inode, __u64 nr,
int create, struct buffer_head **bhp)
{
- return nilfs_mdt_get_block(inode, nilfs_palloc_entry_blkoff(inode, nr),
- create, NULL, bhp);
+ struct nilfs_palloc_cache *cache = NILFS_MDT(inode)->mi_palloc_cache;
+
+ return nilfs_palloc_get_block(inode,
+ nilfs_palloc_entry_blkoff(inode, nr),
+ create, NULL, bhp,
+ &cache->prev_entry, &cache->lock);
}
static struct nilfs_palloc_group_desc *
