btrfs: backref, cleanup __ namespace abuse
authorJeff Mahoney <jeffm@suse.com>
Thu, 29 Jun 2017 03:56:57 +0000 (21:56 -0600)
committerDavid Sterba <dsterba@suse.com>
Wed, 16 Aug 2017 12:19:53 +0000 (14:19 +0200)
We typically use __ to indicate a helper routine that shouldn't be
called directly without understanding the proper context required
to do so.  We use static functions to indicate that a function is
private to a particular C file.  The backref code uses static
function and __ prefixes on nearly everything, which makes the code
difficult to read and establishes a pattern for future code that
shouldn't be followed.  This patch drops all the unnecessary prefixes.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
fs/btrfs/backref.c

index 4a7a4b0..3725277 100644 (file)
@@ -387,7 +387,7 @@ static int find_extent_in_eb(const struct extent_buffer *eb,
 /*
  * this structure records all encountered refs on the way up to the root
  */
-struct __prelim_ref {
+struct prelim_ref {
        struct list_head list;
        u64 root_id;
        struct btrfs_key key_for_search;
@@ -403,7 +403,7 @@ static struct kmem_cache *btrfs_prelim_ref_cache;
 int __init btrfs_prelim_ref_init(void)
 {
        btrfs_prelim_ref_cache = kmem_cache_create("btrfs_prelim_ref",
-                                       sizeof(struct __prelim_ref),
+                                       sizeof(struct prelim_ref),
                                        0,
                                        SLAB_MEM_SPREAD,
                                        NULL);
@@ -449,19 +449,17 @@ void btrfs_prelim_ref_exit(void)
  *
  * - column 1, 3: we've the parent -> done
  * - column 2:    we take the first key from the block to find the parent
- *                (see __add_missing_keys)
+ *                (see add_missing_keys)
  * - column 4:    we use the key to find the parent
  *
  * additional information that's available but not required to find the parent
  * block might help in merging entries to gain some speed.
  */
-
-static int __add_prelim_ref(struct list_head *head, u64 root_id,
-                           const struct btrfs_key *key, int level,
-                           u64 parent, u64 wanted_disk_byte, int count,
-                           gfp_t gfp_mask)
+static int add_prelim_ref(struct list_head *head, u64 root_id,
+                         const struct btrfs_key *key, int level, u64 parent,
+                         u64 wanted_disk_byte, int count, gfp_t gfp_mask)
 {
-       struct __prelim_ref *ref;
+       struct prelim_ref *ref;
 
        if (root_id == BTRFS_DATA_RELOC_TREE_OBJECTID)
                return 0;
@@ -510,7 +508,7 @@ static int __add_prelim_ref(struct list_head *head, u64 root_id,
 }
 
 static int add_all_parents(struct btrfs_root *root, struct btrfs_path *path,
-                          struct ulist *parents, struct __prelim_ref *ref,
+                          struct ulist *parents, struct prelim_ref *ref,
                           int level, u64 time_seq, const u64 *extent_item_pos,
                           u64 total_refs)
 {
@@ -600,11 +598,10 @@ next:
  * resolve an indirect backref in the form (root_id, key, level)
  * to a logical address
  */
-static int __resolve_indirect_ref(struct btrfs_fs_info *fs_info,
-                                 struct btrfs_path *path, u64 time_seq,
-                                 struct __prelim_ref *ref,
-                                 struct ulist *parents,
-                                 const u64 *extent_item_pos, u64 total_refs)
+static int resolve_indirect_ref(struct btrfs_fs_info *fs_info,
+                               struct btrfs_path *path, u64 time_seq,
+                               struct prelim_ref *ref, struct ulist *parents,
+                               const u64 *extent_item_pos, u64 total_refs)
 {
        struct btrfs_root *root;
        struct btrfs_key root_key;
@@ -693,17 +690,17 @@ unode_aux_to_inode_list(struct ulist_node *node)
 /*
  * resolve all indirect backrefs from the list
  */
-static int __resolve_indirect_refs(struct btrfs_fs_info *fs_info,
-                                  struct btrfs_path *path, u64 time_seq,
-                                  struct list_head *head,
-                                  const u64 *extent_item_pos, u64 total_refs,
-                                  u64 root_objectid)
+static int resolve_indirect_refs(struct btrfs_fs_info *fs_info,
+                                struct btrfs_path *path, u64 time_seq,
+                                struct list_head *head,
+                                const u64 *extent_item_pos, u64 total_refs,
+                                u64 root_objectid)
 {
        int err;
        int ret = 0;
-       struct __prelim_ref *ref;
-       struct __prelim_ref *ref_safe;
-       struct __prelim_ref *new_ref;
+       struct prelim_ref *ref;
+       struct prelim_ref *ref_safe;
+       struct prelim_ref *new_ref;
        struct ulist *parents;
        struct ulist_node *node;
        struct ulist_iterator uiter;
@@ -726,9 +723,9 @@ static int __resolve_indirect_refs(struct btrfs_fs_info *fs_info,
                        ret = BACKREF_FOUND_SHARED;
                        goto out;
                }
-               err = __resolve_indirect_ref(fs_info, path, time_seq, ref,
-                                            parents, extent_item_pos,
-                                            total_refs);
+               err = resolve_indirect_ref(fs_info, path, time_seq, ref,
+                                          parents, extent_item_pos,
+                                          total_refs);
                /*
                 * we can only tolerate ENOENT,otherwise,we should catch error
                 * and return directly.
@@ -766,8 +763,8 @@ out:
        return ret;
 }
 
-static inline int ref_for_same_block(struct __prelim_ref *ref1,
-                                    struct __prelim_ref *ref2)
+static inline int ref_for_same_block(struct prelim_ref *ref1,
+                                    struct prelim_ref *ref2)
 {
        if (ref1->level != ref2->level)
                return 0;
@@ -788,10 +785,10 @@ static inline int ref_for_same_block(struct __prelim_ref *ref1,
 /*
  * read tree blocks and add keys where required.
  */
-static int __add_missing_keys(struct btrfs_fs_info *fs_info,
-                             struct list_head *head)
+static int add_missing_keys(struct btrfs_fs_info *fs_info,
+                           struct list_head *head)
 {
-       struct __prelim_ref *ref;
+       struct prelim_ref *ref;
        struct extent_buffer *eb;
 
        list_for_each_entry(ref, head, list) {
@@ -821,20 +818,20 @@ static int __add_missing_keys(struct btrfs_fs_info *fs_info,
 /*
  * merge backrefs and adjust counts accordingly
  *
- *    FIXME: For MERGE_IDENTICAL_KEYS, if we add more keys in __add_prelim_ref
+ *    FIXME: For MERGE_IDENTICAL_KEYS, if we add more keys in add_prelim_ref
  *           then we can merge more here. Additionally, we could even add a key
  *           range for the blocks we looked into to merge even more (-> replace
  *           unresolved refs by those having a parent).
  */
-static void __merge_refs(struct list_head *head, enum merge_mode mode)
+static void merge_refs(struct list_head *head, enum merge_mode mode)
 {
-       struct __prelim_ref *pos1;
+       struct prelim_ref *pos1;
 
        list_for_each_entry(pos1, head, list) {
-               struct __prelim_ref *pos2 = pos1, *tmp;
+               struct prelim_ref *pos2 = pos1, *tmp;
 
                list_for_each_entry_safe_continue(pos2, tmp, head, list) {
-                       struct __prelim_ref *ref1 = pos1, *ref2 = pos2;
+                       struct prelim_ref *ref1 = pos1, *ref2 = pos2;
                        struct extent_inode_elem *eie;
 
                        if (!ref_for_same_block(ref1, ref2))
@@ -868,9 +865,9 @@ static void __merge_refs(struct list_head *head, enum merge_mode mode)
  * add all currently queued delayed refs from this head whose seq nr is
  * smaller or equal that seq to the list
  */
-static int __add_delayed_refs(struct btrfs_delayed_ref_head *head, u64 seq,
-                             struct list_head *prefs, u64 *total_refs,
-                             u64 inum)
+static int add_delayed_refs(struct btrfs_delayed_ref_head *head, u64 seq,
+                           struct list_head *prefs, u64 *total_refs,
+                           u64 inum)
 {
        struct btrfs_delayed_ref_node *node;
        struct btrfs_delayed_extent_op *extent_op = head->extent_op;
@@ -907,19 +904,18 @@ static int __add_delayed_refs(struct btrfs_delayed_ref_head *head, u64 seq,
                        struct btrfs_delayed_tree_ref *ref;
 
                        ref = btrfs_delayed_node_to_tree_ref(node);
-                       ret = __add_prelim_ref(prefs, ref->root, &op_key,
-                                              ref->level + 1, 0, node->bytenr,
-                                              node->ref_mod * sgn, GFP_ATOMIC);
+                       ret = add_prelim_ref(prefs, ref->root, &op_key,
+                                            ref->level + 1, 0, node->bytenr,
+                                            node->ref_mod * sgn, GFP_ATOMIC);
                        break;
                }
                case BTRFS_SHARED_BLOCK_REF_KEY: {
                        struct btrfs_delayed_tree_ref *ref;
 
                        ref = btrfs_delayed_node_to_tree_ref(node);
-                       ret = __add_prelim_ref(prefs, 0, NULL,
-                                              ref->level + 1, ref->parent,
-                                              node->bytenr,
-                                              node->ref_mod * sgn, GFP_ATOMIC);
+                       ret = add_prelim_ref(prefs, 0, NULL, ref->level + 1,
+                                            ref->parent, node->bytenr,
+                                            node->ref_mod * sgn, GFP_ATOMIC);
                        break;
                }
                case BTRFS_EXTENT_DATA_REF_KEY: {
@@ -939,18 +935,18 @@ static int __add_delayed_refs(struct btrfs_delayed_ref_head *head, u64 seq,
                                break;
                        }
 
-                       ret = __add_prelim_ref(prefs, ref->root, &key, 0, 0,
-                                              node->bytenr,
-                                              node->ref_mod * sgn, GFP_ATOMIC);
+                       ret = add_prelim_ref(prefs, ref->root, &key, 0, 0,
+                                            node->bytenr, node->ref_mod * sgn,
+                                            GFP_ATOMIC);
                        break;
                }
                case BTRFS_SHARED_DATA_REF_KEY: {
                        struct btrfs_delayed_data_ref *ref;
 
                        ref = btrfs_delayed_node_to_data_ref(node);
-                       ret = __add_prelim_ref(prefs, 0, NULL, 0,
-                                              ref->parent, node->bytenr,
-                                              node->ref_mod * sgn, GFP_ATOMIC);
+                       ret = add_prelim_ref(prefs, 0, NULL, 0, ref->parent,
+                                            node->bytenr, node->ref_mod * sgn,
+                                            GFP_ATOMIC);
                        break;
                }
                default:
@@ -966,10 +962,10 @@ static int __add_delayed_refs(struct btrfs_delayed_ref_head *head, u64 seq,
 /*
  * add all inline backrefs for bytenr to the list
  */
-static int __add_inline_refs(struct btrfs_path *path, u64 bytenr,
-                            int *info_level, struct list_head *prefs,
-                            struct ref_root *ref_tree,
-                            u64 *total_refs, u64 inum)
+static int add_inline_refs(struct btrfs_path *path, u64 bytenr,
+                          int *info_level, struct list_head *prefs,
+                          struct ref_root *ref_tree,
+                          u64 *total_refs, u64 inum)
 {
        int ret = 0;
        int slot;
@@ -1024,9 +1020,8 @@ static int __add_inline_refs(struct btrfs_path *path, u64 bytenr,
 
                switch (type) {
                case BTRFS_SHARED_BLOCK_REF_KEY:
-                       ret = __add_prelim_ref(prefs, 0, NULL,
-                                               *info_level + 1, offset,
-                                               bytenr, 1, GFP_NOFS);
+                       ret = add_prelim_ref(prefs, 0, NULL, *info_level + 1,
+                                            offset, bytenr, 1, GFP_NOFS);
                        break;
                case BTRFS_SHARED_DATA_REF_KEY: {
                        struct btrfs_shared_data_ref *sdref;
@@ -1034,8 +1029,8 @@ static int __add_inline_refs(struct btrfs_path *path, u64 bytenr,
 
                        sdref = (struct btrfs_shared_data_ref *)(iref + 1);
                        count = btrfs_shared_data_ref_count(leaf, sdref);
-                       ret = __add_prelim_ref(prefs, 0, NULL, 0, offset,
-                                              bytenr, count, GFP_NOFS);
+                       ret = add_prelim_ref(prefs, 0, NULL, 0, offset,
+                                            bytenr, count, GFP_NOFS);
                        if (ref_tree) {
                                if (!ret)
                                        ret = ref_tree_add(ref_tree, 0, 0, 0,
@@ -1046,9 +1041,9 @@ static int __add_inline_refs(struct btrfs_path *path, u64 bytenr,
                        break;
                }
                case BTRFS_TREE_BLOCK_REF_KEY:
-                       ret = __add_prelim_ref(prefs, offset, NULL,
-                                              *info_level + 1, 0,
-                                              bytenr, 1, GFP_NOFS);
+                       ret = add_prelim_ref(prefs, offset, NULL,
+                                            *info_level + 1, 0,
+                                            bytenr, 1, GFP_NOFS);
                        break;
                case BTRFS_EXTENT_DATA_REF_KEY: {
                        struct btrfs_extent_data_ref *dref;
@@ -1068,8 +1063,8 @@ static int __add_inline_refs(struct btrfs_path *path, u64 bytenr,
                        }
 
                        root = btrfs_extent_data_ref_root(leaf, dref);
-                       ret = __add_prelim_ref(prefs, root, &key, 0, 0,
-                                              bytenr, count, GFP_NOFS);
+                       ret = add_prelim_ref(prefs, root, &key, 0, 0,
+                                            bytenr, count, GFP_NOFS);
                        if (ref_tree) {
                                if (!ret)
                                        ret = ref_tree_add(ref_tree, root,
@@ -1095,10 +1090,10 @@ static int __add_inline_refs(struct btrfs_path *path, u64 bytenr,
 /*
  * add all non-inline backrefs for bytenr to the list
  */
-static int __add_keyed_refs(struct btrfs_fs_info *fs_info,
-                           struct btrfs_path *path, u64 bytenr,
-                           int info_level, struct list_head *prefs,
-                           struct ref_root *ref_tree, u64 inum)
+static int add_keyed_refs(struct btrfs_fs_info *fs_info,
+                         struct btrfs_path *path, u64 bytenr,
+                         int info_level, struct list_head *prefs,
+                         struct ref_root *ref_tree, u64 inum)
 {
        struct btrfs_root *extent_root = fs_info->extent_root;
        int ret;
@@ -1128,9 +1123,8 @@ static int __add_keyed_refs(struct btrfs_fs_info *fs_info,
 
                switch (key.type) {
                case BTRFS_SHARED_BLOCK_REF_KEY:
-                       ret = __add_prelim_ref(prefs, 0, NULL,
-                                               info_level + 1, key.offset,
-                                               bytenr, 1, GFP_NOFS);
+                       ret = add_prelim_ref(prefs, 0, NULL, info_level + 1,
+                                            key.offset, bytenr, 1, GFP_NOFS);
                        break;
                case BTRFS_SHARED_DATA_REF_KEY: {
                        struct btrfs_shared_data_ref *sdref;
@@ -1139,8 +1133,8 @@ static int __add_keyed_refs(struct btrfs_fs_info *fs_info,
                        sdref = btrfs_item_ptr(leaf, slot,
                                              struct btrfs_shared_data_ref);
                        count = btrfs_shared_data_ref_count(leaf, sdref);
-                       ret = __add_prelim_ref(prefs, 0, NULL, 0, key.offset,
-                                               bytenr, count, GFP_NOFS);
+                       ret = add_prelim_ref(prefs, 0, NULL, 0, key.offset,
+                                            bytenr, count, GFP_NOFS);
                        if (ref_tree) {
                                if (!ret)
                                        ret = ref_tree_add(ref_tree, 0, 0, 0,
@@ -1151,9 +1145,9 @@ static int __add_keyed_refs(struct btrfs_fs_info *fs_info,
                        break;
                }
                case BTRFS_TREE_BLOCK_REF_KEY:
-                       ret = __add_prelim_ref(prefs, key.offset, NULL,
-                                              info_level + 1, 0,
-                                              bytenr, 1, GFP_NOFS);
+                       ret = add_prelim_ref(prefs, key.offset, NULL,
+                                            info_level + 1, 0,
+                                            bytenr, 1, GFP_NOFS);
                        break;
                case BTRFS_EXTENT_DATA_REF_KEY: {
                        struct btrfs_extent_data_ref *dref;
@@ -1174,8 +1168,8 @@ static int __add_keyed_refs(struct btrfs_fs_info *fs_info,
                        }
 
                        root = btrfs_extent_data_ref_root(leaf, dref);
-                       ret = __add_prelim_ref(prefs, root, &key, 0, 0,
-                                              bytenr, count, GFP_NOFS);
+                       ret = add_prelim_ref(prefs, root, &key, 0, 0,
+                                            bytenr, count, GFP_NOFS);
                        if (ref_tree) {
                                if (!ret)
                                        ret = ref_tree_add(ref_tree, root,
@@ -1230,7 +1224,7 @@ static int find_parent_nodes(struct btrfs_trans_handle *trans,
        int ret;
        struct list_head prefs_delayed;
        struct list_head prefs;
-       struct __prelim_ref *ref;
+       struct prelim_ref *ref;
        struct extent_inode_elem *eie = NULL;
        struct ref_root *ref_tree = NULL;
        u64 total_refs = 0;
@@ -1311,9 +1305,9 @@ again:
                                goto again;
                        }
                        spin_unlock(&delayed_refs->lock);
-                       ret = __add_delayed_refs(head, time_seq,
-                                                &prefs_delayed, &total_refs,
-                                                inum);
+                       ret = add_delayed_refs(head, time_seq,
+                                              &prefs_delayed, &total_refs,
+                                              inum);
                        mutex_unlock(&head->mutex);
                        if (ret)
                                goto out;
@@ -1363,15 +1357,13 @@ again:
                if (key.objectid == bytenr &&
                    (key.type == BTRFS_EXTENT_ITEM_KEY ||
                     key.type == BTRFS_METADATA_ITEM_KEY)) {
-                       ret = __add_inline_refs(path, bytenr,
-                                               &info_level, &prefs,
-                                               ref_tree, &total_refs,
-                                               inum);
+                       ret = add_inline_refs(path, bytenr, &info_level,
+                                             &prefs, ref_tree, &total_refs,
+                                             inum);
                        if (ret)
                                goto out;
-                       ret = __add_keyed_refs(fs_info, path, bytenr,
-                                              info_level, &prefs,
-                                              ref_tree, inum);
+                       ret = add_keyed_refs(fs_info, path, bytenr, info_level,
+                                            &prefs, ref_tree, inum);
                        if (ret)
                                goto out;
                }
@@ -1380,22 +1372,22 @@ again:
 
        list_splice_init(&prefs_delayed, &prefs);
 
-       ret = __add_missing_keys(fs_info, &prefs);
+       ret = add_missing_keys(fs_info, &prefs);
        if (ret)
                goto out;
 
-       __merge_refs(&prefs, MERGE_IDENTICAL_KEYS);
+       merge_refs(&prefs, MERGE_IDENTICAL_KEYS);
 
-       ret = __resolve_indirect_refs(fs_info, path, time_seq, &prefs,
-                                     extent_item_pos, total_refs,
-                                     root_objectid);
+       ret = resolve_indirect_refs(fs_info, path, time_seq, &prefs,
+                                   extent_item_pos, total_refs,
+                                   root_objectid);
        if (ret)
                goto out;
 
-       __merge_refs(&prefs, MERGE_IDENTICAL_PARENTS);
+       merge_refs(&prefs, MERGE_IDENTICAL_PARENTS);
 
        while (!list_empty(&prefs)) {
-               ref = list_first_entry(&prefs, struct __prelim_ref, list);
+               ref = list_first_entry(&prefs, struct prelim_ref, list);
                WARN_ON(ref->count < 0);
                if (roots && ref->count && ref->root_id && ref->parent == 0) {
                        if (root_objectid && ref->root_id != root_objectid) {
@@ -1457,12 +1449,12 @@ out:
        btrfs_free_path(path);
        ref_root_free(ref_tree);
        while (!list_empty(&prefs)) {
-               ref = list_first_entry(&prefs, struct __prelim_ref, list);
+               ref = list_first_entry(&prefs, struct prelim_ref, list);
                list_del(&ref->list);
                kmem_cache_free(btrfs_prelim_ref_cache, ref);
        }
        while (!list_empty(&prefs_delayed)) {
-               ref = list_first_entry(&prefs_delayed, struct __prelim_ref,
+               ref = list_first_entry(&prefs_delayed, struct prelim_ref,
                                       list);
                list_del(&ref->list);
                kmem_cache_free(btrfs_prelim_ref_cache, ref);
@@ -1532,9 +1524,9 @@ static int btrfs_find_all_leafs(struct btrfs_trans_handle *trans,
  *
  * returns 0 on success, < 0 on error.
  */
-static int __btrfs_find_all_roots(struct btrfs_trans_handle *trans,
-                                 struct btrfs_fs_info *fs_info, u64 bytenr,
-                                 u64 time_seq, struct ulist **roots)
+static int btrfs_find_all_roots_safe(struct btrfs_trans_handle *trans,
+                                    struct btrfs_fs_info *fs_info, u64 bytenr,
+                                    u64 time_seq, struct ulist **roots)
 {
        struct ulist *tmp;
        struct ulist_node *node = NULL;
@@ -1578,7 +1570,8 @@ int btrfs_find_all_roots(struct btrfs_trans_handle *trans,
 
        if (!trans)
                down_read(&fs_info->commit_root_sem);
-       ret = __btrfs_find_all_roots(trans, fs_info, bytenr, time_seq, roots);
+       ret = btrfs_find_all_roots_safe(trans, fs_info, bytenr,
+                                       time_seq, roots);
        if (!trans)
                up_read(&fs_info->commit_root_sem);
        return ret;
@@ -1877,17 +1870,17 @@ int extent_from_logical(struct btrfs_fs_info *fs_info, u64 logical,
  * helper function to iterate extent inline refs. ptr must point to a 0 value
  * for the first call and may be modified. it is used to track state.
  * if more refs exist, 0 is returned and the next call to
- * __get_extent_inline_ref must pass the modified ptr parameter to get the
+ * get_extent_inline_ref must pass the modified ptr parameter to get the
  * next ref. after the last ref was processed, 1 is returned.
  * returns <0 on error
  */
-static int __get_extent_inline_ref(unsigned long *ptr,
-                                  const struct extent_buffer *eb,
-                                  const struct btrfs_key *key,
-                                  const struct btrfs_extent_item *ei,
-                                  u32 item_size,
-                                  struct btrfs_extent_inline_ref **out_eiref,
-                                  int *out_type)
+static int get_extent_inline_ref(unsigned long *ptr,
+                                const struct extent_buffer *eb,
+                                const struct btrfs_key *key,
+                                const struct btrfs_extent_item *ei,
+                                u32 item_size,
+                                struct btrfs_extent_inline_ref **out_eiref,
+                                int *out_type)
 {
        unsigned long end;
        u64 flags;
@@ -1930,7 +1923,7 @@ static int __get_extent_inline_ref(unsigned long *ptr,
 /*
  * reads the tree block backref for an extent. tree level and root are returned
  * through out_level and out_root. ptr must point to a 0 value for the first
- * call and may be modified (see __get_extent_inline_ref comment).
+ * call and may be modified (see get_extent_inline_ref comment).
  * returns 0 if data was provided, 1 if there was no more data to provide or
  * <0 on error.
  */
@@ -1946,7 +1939,7 @@ int tree_backref_for_extent(unsigned long *ptr, struct extent_buffer *eb,
                return 1;
 
        while (1) {
-               ret = __get_extent_inline_ref(ptr, eb, key, ei, item_size,
+               ret = get_extent_inline_ref(ptr, eb, key, ei, item_size,
                                              &eiref, &type);
                if (ret < 0)
                        return ret;
@@ -2043,8 +2036,8 @@ int iterate_extent_inodes(struct btrfs_fs_info *fs_info,
 
        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,
-                                            tree_mod_seq_elem.seq, &roots);
+               ret = btrfs_find_all_roots_safe(trans, fs_info, ref_node->val,
+                                               tree_mod_seq_elem.seq, &roots);
                if (ret)
                        break;
                ULIST_ITER_INIT(&root_uiter);