diff --git a/fs/btrfs/send.c b/fs/btrfs/send.c index 9cee678c0fb654f923241d8c1e95393cf0ac68ab..02e901adc3e830bc3ed34781d1d623a5323be76b 100644 --- a/fs/btrfs/send.c +++ b/fs/btrfs/send.c @@ -125,6 +125,15 @@ struct send_ctx { struct name_cache_entry { struct list_head list; + /* + * radix_tree has only 32bit entries but we need to handle 64bit inums. + * We use the lower 32bit of the 64bit inum to store it in the tree. If + * more then one inum would fall into the same entry, we use radix_list + * to store the additional entries. radix_list is also used to store + * entries where two entries have the same inum but different + * generations. + */ + struct list_head radix_list; u64 ino; u64 gen; u64 parent_ino; @@ -1726,27 +1735,21 @@ static int name_cache_insert(struct send_ctx *sctx, struct name_cache_entry *nce) { int ret = 0; - struct name_cache_entry **ncea; - - ncea = radix_tree_lookup(&sctx->name_cache, nce->ino); - if (ncea) { - if (!ncea[0]) - ncea[0] = nce; - else if (!ncea[1]) - ncea[1] = nce; - else - BUG(); - } else { - ncea = kmalloc(sizeof(void *) * 2, GFP_NOFS); - if (!ncea) + struct list_head *nce_head; + + nce_head = radix_tree_lookup(&sctx->name_cache, + (unsigned long)nce->ino); + if (!nce_head) { + nce_head = kmalloc(sizeof(*nce_head), GFP_NOFS); + if (!nce_head) return -ENOMEM; + INIT_LIST_HEAD(nce_head); - ncea[0] = nce; - ncea[1] = NULL; - ret = radix_tree_insert(&sctx->name_cache, nce->ino, ncea); + ret = radix_tree_insert(&sctx->name_cache, nce->ino, nce_head); if (ret < 0) return ret; } + list_add_tail(&nce->radix_list, nce_head); list_add_tail(&nce->list, &sctx->name_cache_list); sctx->name_cache_size++; @@ -1756,41 +1759,36 @@ static int name_cache_insert(struct send_ctx *sctx, static void name_cache_delete(struct send_ctx *sctx, struct name_cache_entry *nce) { - struct name_cache_entry **ncea; - - ncea = radix_tree_lookup(&sctx->name_cache, nce->ino); - BUG_ON(!ncea); - - if (ncea[0] == nce) - ncea[0] = NULL; - else if (ncea[1] == nce) - ncea[1] = NULL; - else - BUG(); + struct list_head *nce_head; - if (!ncea[0] && !ncea[1]) { - radix_tree_delete(&sctx->name_cache, nce->ino); - kfree(ncea); - } + nce_head = radix_tree_lookup(&sctx->name_cache, + (unsigned long)nce->ino); + BUG_ON(!nce_head); + list_del(&nce->radix_list); list_del(&nce->list); - sctx->name_cache_size--; + + if (list_empty(nce_head)) { + radix_tree_delete(&sctx->name_cache, (unsigned long)nce->ino); + kfree(nce_head); + } } static struct name_cache_entry *name_cache_search(struct send_ctx *sctx, u64 ino, u64 gen) { - struct name_cache_entry **ncea; + struct list_head *nce_head; + struct name_cache_entry *cur; - ncea = radix_tree_lookup(&sctx->name_cache, ino); - if (!ncea) + nce_head = radix_tree_lookup(&sctx->name_cache, (unsigned long)ino); + if (!nce_head) return NULL; - if (ncea[0] && ncea[0]->gen == gen) - return ncea[0]; - else if (ncea[1] && ncea[1]->gen == gen) - return ncea[1]; + list_for_each_entry(cur, nce_head, radix_list) { + if (cur->ino == ino && cur->gen == gen) + return cur; + } return NULL; }