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authorQu Wenruo <quwenruo@cn.fujitsu.com>2015-04-20 09:26:02 +0800
committerChris Mason <clm@fb.com>2015-06-10 09:26:17 -0700
commitd4b804045924d7f8d2ea988be22c4b9e6492ec11 (patch)
tree9b866bbf41de8dfa612f1f50575b62f01f26cfae
parente69bcee37692f5d8c557335ddd2444cb4afe0005 (diff)
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btrfs: ulist: Add ulist_del() function.
This function will delete unode with given (val,aux) pair. And with this patch, seqnum for debug usage doesn't have any meaning now, so remove them. This is used by later patches to skip snapshot root. Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com> Signed-off-by: Chris Mason <clm@fb.com>
-rw-r--r--fs/btrfs/ulist.c47
-rw-r--r--fs/btrfs/ulist.h1
2 files changed, 37 insertions, 11 deletions
diff --git a/fs/btrfs/ulist.c b/fs/btrfs/ulist.c
index 840a38b2778a..91feb2bdefee 100644
--- a/fs/btrfs/ulist.c
+++ b/fs/btrfs/ulist.c
@@ -132,6 +132,15 @@ static struct ulist_node *ulist_rbtree_search(struct ulist *ulist, u64 val)
return NULL;
}
+static void ulist_rbtree_erase(struct ulist *ulist, struct ulist_node *node)
+{
+ rb_erase(&node->rb_node, &ulist->root);
+ list_del(&node->list);
+ kfree(node);
+ BUG_ON(ulist->nnodes == 0);
+ ulist->nnodes--;
+}
+
static int ulist_rbtree_insert(struct ulist *ulist, struct ulist_node *ins)
{
struct rb_node **p = &ulist->root.rb_node;
@@ -197,9 +206,6 @@ int ulist_add_merge(struct ulist *ulist, u64 val, u64 aux,
node->val = val;
node->aux = aux;
-#ifdef CONFIG_BTRFS_DEBUG
- node->seqnum = ulist->nnodes;
-#endif
ret = ulist_rbtree_insert(ulist, node);
ASSERT(!ret);
@@ -209,6 +215,33 @@ int ulist_add_merge(struct ulist *ulist, u64 val, u64 aux,
return 1;
}
+/*
+ * ulist_del - delete one node from ulist
+ * @ulist: ulist to remove node from
+ * @val: value to delete
+ * @aux: aux to delete
+ *
+ * The deletion will only be done when *BOTH* val and aux matches.
+ * Return 0 for successful delete.
+ * Return > 0 for not found.
+ */
+int ulist_del(struct ulist *ulist, u64 val, u64 aux)
+{
+ struct ulist_node *node;
+
+ node = ulist_rbtree_search(ulist, val);
+ /* Not found */
+ if (!node)
+ return 1;
+
+ if (node->aux != aux)
+ return 1;
+
+ /* Found and delete */
+ ulist_rbtree_erase(ulist, node);
+ return 0;
+}
+
/**
* ulist_next - iterate ulist
* @ulist: ulist to iterate
@@ -237,15 +270,7 @@ struct ulist_node *ulist_next(struct ulist *ulist, struct ulist_iterator *uiter)
uiter->cur_list = uiter->cur_list->next;
} else {
uiter->cur_list = ulist->nodes.next;
-#ifdef CONFIG_BTRFS_DEBUG
- uiter->i = 0;
-#endif
}
node = list_entry(uiter->cur_list, struct ulist_node, list);
-#ifdef CONFIG_BTRFS_DEBUG
- ASSERT(node->seqnum == uiter->i);
- ASSERT(uiter->i >= 0 && uiter->i < ulist->nnodes);
- uiter->i++;
-#endif
return node;
}
diff --git a/fs/btrfs/ulist.h b/fs/btrfs/ulist.h
index 4c29db604bbe..a01a2c45825f 100644
--- a/fs/btrfs/ulist.h
+++ b/fs/btrfs/ulist.h
@@ -57,6 +57,7 @@ void ulist_free(struct ulist *ulist);
int ulist_add(struct ulist *ulist, u64 val, u64 aux, gfp_t gfp_mask);
int ulist_add_merge(struct ulist *ulist, u64 val, u64 aux,
u64 *old_aux, gfp_t gfp_mask);
+int ulist_del(struct ulist *ulist, u64 val, u64 aux);
/* just like ulist_add_merge() but take a pointer for the aux data */
static inline int ulist_add_merge_ptr(struct ulist *ulist, u64 val, void *aux,