diff options
| -rw-r--r-- | fs/nilfs2/the_nilfs.c | 92 | ||||
| -rw-r--r-- | fs/nilfs2/the_nilfs.h | 42 |
2 files changed, 134 insertions, 0 deletions
diff --git a/fs/nilfs2/the_nilfs.c b/fs/nilfs2/the_nilfs.c index 6a012b9e1b31..f1d599273d9e 100644 --- a/fs/nilfs2/the_nilfs.c +++ b/fs/nilfs2/the_nilfs.c @@ -89,6 +89,8 @@ static struct the_nilfs *alloc_nilfs(struct block_device *bdev) INIT_LIST_HEAD(&nilfs->ns_supers); INIT_LIST_HEAD(&nilfs->ns_gc_inodes); spin_lock_init(&nilfs->ns_last_segment_lock); + nilfs->ns_cptree = RB_ROOT; + spin_lock_init(&nilfs->ns_cptree_lock); init_rwsem(&nilfs->ns_segctor_sem); return nilfs; @@ -809,6 +811,96 @@ int nilfs_near_disk_full(struct the_nilfs *nilfs) return ncleansegs <= nilfs->ns_nrsvsegs + nincsegs; } +struct nilfs_root *nilfs_lookup_root(struct the_nilfs *nilfs, __u64 cno) +{ + struct rb_node *n; + struct nilfs_root *root; + + spin_lock(&nilfs->ns_cptree_lock); + n = nilfs->ns_cptree.rb_node; + while (n) { + root = rb_entry(n, struct nilfs_root, rb_node); + + if (cno < root->cno) { + n = n->rb_left; + } else if (cno > root->cno) { + n = n->rb_right; + } else { + atomic_inc(&root->count); + spin_unlock(&nilfs->ns_cptree_lock); + return root; + } + } + spin_unlock(&nilfs->ns_cptree_lock); + + return NULL; +} + +struct nilfs_root * +nilfs_find_or_create_root(struct the_nilfs *nilfs, __u64 cno) +{ + struct rb_node **p, *parent; + struct nilfs_root *root, *new; + + root = nilfs_lookup_root(nilfs, cno); + if (root) + return root; + + new = kmalloc(sizeof(*root), GFP_KERNEL); + if (!new) + return NULL; + + spin_lock(&nilfs->ns_cptree_lock); + + p = &nilfs->ns_cptree.rb_node; + parent = NULL; + + while (*p) { + parent = *p; + root = rb_entry(parent, struct nilfs_root, rb_node); + + if (cno < root->cno) { + p = &(*p)->rb_left; + } else if (cno > root->cno) { + p = &(*p)->rb_right; + } else { + atomic_inc(&root->count); + spin_unlock(&nilfs->ns_cptree_lock); + kfree(new); + return root; + } + } + + new->cno = cno; + new->ifile = NULL; + new->nilfs = nilfs; + atomic_set(&new->count, 1); + atomic_set(&new->inodes_count, 0); + atomic_set(&new->blocks_count, 0); + + rb_link_node(&new->rb_node, parent, p); + rb_insert_color(&new->rb_node, &nilfs->ns_cptree); + + spin_unlock(&nilfs->ns_cptree_lock); + + return new; +} + +void nilfs_put_root(struct nilfs_root *root) +{ + if (atomic_dec_and_test(&root->count)) { + struct the_nilfs *nilfs = root->nilfs; + + spin_lock(&nilfs->ns_cptree_lock); + rb_erase(&root->rb_node, &nilfs->ns_cptree); + spin_unlock(&nilfs->ns_cptree_lock); + if (root->ifile) + nilfs_mdt_destroy(root->ifile); + + kfree(root); + } +} + /** * nilfs_find_sbinfo - find existing nilfs_sb_info structure * @nilfs: nilfs object diff --git a/fs/nilfs2/the_nilfs.h b/fs/nilfs2/the_nilfs.h index c7ecd0c623a3..0afede68a9e1 100644 --- a/fs/nilfs2/the_nilfs.h +++ b/fs/nilfs2/the_nilfs.h @@ -26,6 +26,7 @@ #include <linux/types.h> #include <linux/buffer_head.h> +#include <linux/rbtree.h> #include <linux/fs.h> #include <linux/blkdev.h> #include <linux/backing-dev.h> @@ -80,6 +81,8 @@ enum { * @ns_cpfile: checkpoint file inode * @ns_sufile: segusage file inode * @ns_gc_dat: shadow inode of the DAT file inode for GC + * @ns_cptree: rb-tree of all mounted checkpoints (nilfs_root) + * @ns_cptree_lock: lock protecting @ns_cptree * @ns_gc_inodes: dummy inodes to keep live blocks * @ns_blocksize_bits: bit length of block size * @ns_blocksize: block size @@ -164,6 +167,10 @@ struct the_nilfs { struct inode *ns_sufile; struct inode *ns_gc_dat; + /* Checkpoint tree */ + struct rb_root ns_cptree; + spinlock_t ns_cptree_lock; + /* GC inode list */ struct list_head ns_gc_inodes; @@ -200,6 +207,32 @@ THE_NILFS_FNS(DISCONTINUED, discontinued) THE_NILFS_FNS(GC_RUNNING, gc_running) THE_NILFS_FNS(SB_DIRTY, sb_dirty) +/** + * struct nilfs_root - nilfs root object + * @cno: checkpoint number + * @rb_node: red-black tree node + * @count: refcount of this structure + * @nilfs: nilfs object + * @ifile: inode file + * @root: root inode + * @inodes_count: number of inodes + * @blocks_count: number of blocks (Reserved) + */ +struct nilfs_root { + __u64 cno; + struct rb_node rb_node; + + atomic_t count; + struct the_nilfs *nilfs; + struct inode *ifile; + + atomic_t inodes_count; + atomic_t blocks_count; +}; + +/* Special checkpoint number */ +#define NILFS_CPTREE_CURRENT_CNO 0 + /* Minimum interval of periodical update of superblocks (in seconds) */ #define NILFS_SB_FREQ 10 @@ -222,6 +255,10 @@ int init_nilfs(struct the_nilfs *, struct nilfs_sb_info *, char *); int load_nilfs(struct the_nilfs *, struct nilfs_sb_info *); int nilfs_discard_segments(struct the_nilfs *, __u64 *, size_t); int nilfs_count_free_blocks(struct the_nilfs *, sector_t *); +struct nilfs_root *nilfs_lookup_root(struct the_nilfs *nilfs, __u64 cno); +struct nilfs_root *nilfs_find_or_create_root(struct the_nilfs *nilfs, + __u64 cno); +void nilfs_put_root(struct nilfs_root *root); struct nilfs_sb_info *nilfs_find_sbinfo(struct the_nilfs *, int, __u64); int nilfs_checkpoint_is_mounted(struct the_nilfs *, __u64, int); int nilfs_near_disk_full(struct the_nilfs *); @@ -235,6 +272,11 @@ static inline void get_nilfs(struct the_nilfs *nilfs) atomic_inc(&nilfs->ns_count); } +static inline void nilfs_get_root(struct nilfs_root *root) +{ + atomic_inc(&root->count); +} + static inline void nilfs_attach_writer(struct the_nilfs *nilfs, struct nilfs_sb_info *sbi) { |