On Fri, Apr 01, 2016 at 02:34:55PM +0800, Qu Wenruo wrote: > From: Wang Xiaoguang <wangxg.f...@cn.fujitsu.com> > > Introduce static function inmem_del() to remove hash from in-memory > dedupe tree. > And implement btrfs_dedupe_del() and btrfs_dedup_destroy() interfaces. > > Signed-off-by: Qu Wenruo <quwen...@cn.fujitsu.com> > Signed-off-by: Wang Xiaoguang <wangxg.f...@cn.fujitsu.com> > --- > fs/btrfs/dedupe.c | 105 > ++++++++++++++++++++++++++++++++++++++++++++++++++++++ > 1 file changed, 105 insertions(+) > > diff --git a/fs/btrfs/dedupe.c b/fs/btrfs/dedupe.c > index 4e8455e..a229ded 100644 > --- a/fs/btrfs/dedupe.c > +++ b/fs/btrfs/dedupe.c > @@ -303,3 +303,108 @@ int btrfs_dedupe_add(struct btrfs_trans_handle *trans, > return inmem_add(dedupe_info, hash); > return -EINVAL; > } > + > +static struct inmem_hash * > +inmem_search_bytenr(struct btrfs_dedupe_info *dedupe_info, u64 bytenr) > +{ > + struct rb_node **p = &dedupe_info->bytenr_root.rb_node; > + struct rb_node *parent = NULL; > + struct inmem_hash *entry = NULL; > + > + while (*p) { > + parent = *p; > + entry = rb_entry(parent, struct inmem_hash, bytenr_node); > + > + if (bytenr < entry->bytenr) > + p = &(*p)->rb_left; > + else if (bytenr > entry->bytenr) > + p = &(*p)->rb_right; > + else > + return entry; > + } > + > + return NULL; > +} > + > +/* Delete a hash from in-memory dedupe tree */ > +static int inmem_del(struct btrfs_dedupe_info *dedupe_info, u64 bytenr) > +{ > + struct inmem_hash *hash; > + > + mutex_lock(&dedupe_info->lock); > + hash = inmem_search_bytenr(dedupe_info, bytenr); > + if (!hash) { > + mutex_unlock(&dedupe_info->lock); > + return 0; > + } > + > + __inmem_del(dedupe_info, hash); > + mutex_unlock(&dedupe_info->lock); > + return 0; > +} > + > +/* Remove a dedupe hash from dedupe tree */ > +int btrfs_dedupe_del(struct btrfs_trans_handle *trans, > + struct btrfs_fs_info *fs_info, u64 bytenr) > +{ > + struct btrfs_dedupe_info *dedupe_info = fs_info->dedupe_info; > + > + if (!fs_info->dedupe_enabled) > + return 0; > + > + if (WARN_ON(dedupe_info == NULL)) > + return -EINVAL; > + > + if (dedupe_info->backend == BTRFS_DEDUPE_BACKEND_INMEMORY) > + return inmem_del(dedupe_info, bytenr); > + return -EINVAL; > +} > + > +static void inmem_destroy(struct btrfs_dedupe_info *dedupe_info) > +{ > + struct inmem_hash *entry, *tmp; > + > + mutex_lock(&dedupe_info->lock); > + list_for_each_entry_safe(entry, tmp, &dedupe_info->lru_list, lru_list) > + __inmem_del(dedupe_info, entry); > + mutex_unlock(&dedupe_info->lock); > +} > + > +int btrfs_dedupe_disable(struct btrfs_fs_info *fs_info) > +{ > + struct btrfs_dedupe_info *dedupe_info; > + int ret; > + > + /* Here we don't want to increase refs of dedupe_info */ > + fs_info->dedupe_enabled = 0;
Can this clear of fs_info->dedupe_enabled race with another thread in write? I don't see any locking (but perhaps that comes in a later patch). --Mark -- Mark Fasheh -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html