diff options
| -rw-r--r-- | fs/btrfs/backref.c | 18 | ||||
| -rw-r--r-- | fs/btrfs/ulist.c | 23 | ||||
| -rw-r--r-- | fs/btrfs/ulist.h | 9 |
3 files changed, 29 insertions, 21 deletions
diff --git a/fs/btrfs/backref.c b/fs/btrfs/backref.c index bcec06750232..b41d94a6471b 100644 --- a/fs/btrfs/backref.c +++ b/fs/btrfs/backref.c @@ -201,6 +201,7 @@ static int __resolve_indirect_refs(struct btrfs_fs_info *fs_info, struct __prelim_ref *new_ref; struct ulist *parents; struct ulist_node *node; + struct ulist_iterator uiter; parents = ulist_alloc(GFP_NOFS); if (!parents) @@ -225,11 +226,12 @@ static int __resolve_indirect_refs(struct btrfs_fs_info *fs_info, } /* we put the first parent into the ref at hand */ - node = ulist_next(parents, NULL); + ULIST_ITER_INIT(&uiter); + node = ulist_next(parents, &uiter); ref->parent = node ? node->val : 0; /* additional parents require new refs being added here */ - while ((node = ulist_next(parents, node))) { + while ((node = ulist_next(parents, &uiter))) { new_ref = kmalloc(sizeof(*new_ref), GFP_NOFS); if (!new_ref) { ret = -ENOMEM; @@ -788,6 +790,7 @@ int btrfs_find_all_roots(struct btrfs_trans_handle *trans, { struct ulist *tmp; struct ulist_node *node = NULL; + struct ulist_iterator uiter; int ret; tmp = ulist_alloc(GFP_NOFS); @@ -799,6 +802,7 @@ int btrfs_find_all_roots(struct btrfs_trans_handle *trans, return -ENOMEM; } + ULIST_ITER_INIT(&uiter); while (1) { ret = find_parent_nodes(trans, fs_info, bytenr, seq, tmp, *roots); @@ -807,7 +811,7 @@ int btrfs_find_all_roots(struct btrfs_trans_handle *trans, ulist_free(*roots); return ret; } - node = ulist_next(tmp, node); + node = ulist_next(tmp, &uiter); if (!node) break; bytenr = node->val; @@ -1176,6 +1180,8 @@ int iterate_extent_inodes(struct btrfs_fs_info *fs_info, struct ulist_node *ref_node = NULL; struct ulist_node *root_node = NULL; struct seq_list seq_elem; + struct ulist_iterator ref_uiter; + struct ulist_iterator root_uiter; struct btrfs_delayed_ref_root *delayed_refs = NULL; pr_debug("resolving all inodes for extent %llu\n", @@ -1201,12 +1207,14 @@ int iterate_extent_inodes(struct btrfs_fs_info *fs_info, if (ret) goto out; - while (!ret && (ref_node = ulist_next(refs, ref_node))) { + ULIST_ITER_INIT(&ref_uiter); + while (!ret && (ref_node = ulist_next(refs, &ref_uiter))) { ret = btrfs_find_all_roots(trans, fs_info, ref_node->val, -1, seq_elem.seq, &roots); if (ret) break; - while (!ret && (root_node = ulist_next(roots, root_node))) { + ULIST_ITER_INIT(&root_uiter); + while (!ret && (root_node = ulist_next(roots, &root_uiter))) { pr_debug("root %llu references leaf %llu\n", root_node->val, ref_node->val); ret = iterate_leaf_refs(fs_info, ref_node->val, diff --git a/fs/btrfs/ulist.c b/fs/btrfs/ulist.c index 12f5147bd2b1..17e68bdc307c 100644 --- a/fs/btrfs/ulist.c +++ b/fs/btrfs/ulist.c @@ -23,9 +23,9 @@ * * ulist = ulist_alloc(); * ulist_add(ulist, root); - * elem = NULL; + * ULIST_ITER_INIT(&uiter); * - * while ((elem = ulist_next(ulist, elem)) { + * while ((elem = ulist_next(ulist, &uiter)) { * for (all child nodes n in elem) * ulist_add(ulist, n); * do something useful with the node; @@ -188,33 +188,26 @@ EXPORT_SYMBOL(ulist_add); /** * ulist_next - iterate ulist * @ulist: ulist to iterate - * @prev: previously returned element or %NULL to start iteration + * @uiter: iterator variable, initialized with ULIST_ITER_INIT(&iterator) * * Note: locking must be provided by the caller. In case of rwlocks only read * locking is needed * - * This function is used to iterate an ulist. The iteration is started with - * @prev = %NULL. It returns the next element from the ulist or %NULL when the + * This function is used to iterate an ulist. + * It returns the next element from the ulist or %NULL when the * end is reached. No guarantee is made with respect to the order in which * the elements are returned. They might neither be returned in order of * addition nor in ascending order. * It is allowed to call ulist_add during an enumeration. Newly added items * are guaranteed to show up in the running enumeration. */ -struct ulist_node *ulist_next(struct ulist *ulist, struct ulist_node *prev) +struct ulist_node *ulist_next(struct ulist *ulist, struct ulist_iterator *uiter) { - int next; - if (ulist->nnodes == 0) return NULL; - - if (!prev) - return &ulist->nodes[0]; - - next = (prev - ulist->nodes) + 1; - if (next < 0 || next >= ulist->nnodes) + if (uiter->i < 0 || uiter->i >= ulist->nnodes) return NULL; - return &ulist->nodes[next]; + return &ulist->nodes[uiter->i++]; } EXPORT_SYMBOL(ulist_next); diff --git a/fs/btrfs/ulist.h b/fs/btrfs/ulist.h index 2e25dec58ec0..62d2574f775a 100644 --- a/fs/btrfs/ulist.h +++ b/fs/btrfs/ulist.h @@ -24,6 +24,10 @@ */ #define ULIST_SIZE 16 +struct ulist_iterator { + int i; +}; + /* * element of the list */ @@ -63,6 +67,9 @@ struct ulist *ulist_alloc(unsigned long gfp_mask); void ulist_free(struct ulist *ulist); int ulist_add(struct ulist *ulist, u64 val, unsigned long aux, unsigned long gfp_mask); -struct ulist_node *ulist_next(struct ulist *ulist, struct ulist_node *prev); +struct ulist_node *ulist_next(struct ulist *ulist, + struct ulist_iterator *uiter); + +#define ULIST_ITER_INIT(uiter) ((uiter)->i = 0) #endif |