]> git.sesse.net Git - bcachefs-tools-debian/blobdiff - libbcachefs/recovery.c
Update bcachefs sources to fd381c355c bcachefs: Fix a null ptr deref in fsck check_ex...
[bcachefs-tools-debian] / libbcachefs / recovery.c
index 0b923037d236fb847490979ba4658be77171b6c1..91a66b5916eb7ed0d2629c0ee64424678ae7ec3b 100644 (file)
@@ -1,6 +1,7 @@
 // SPDX-License-Identifier: GPL-2.0
 
 #include "bcachefs.h"
+#include "backpointers.h"
 #include "bkey_buf.h"
 #include "alloc_background.h"
 #include "btree_gc.h"
 #include "buckets.h"
 #include "dirent.h"
 #include "ec.h"
+#include "errcode.h"
 #include "error.h"
 #include "fs-common.h"
 #include "fsck.h"
 #include "journal_io.h"
 #include "journal_reclaim.h"
 #include "journal_seq_blacklist.h"
+#include "lru.h"
 #include "move.h"
 #include "quota.h"
 #include "recovery.h"
@@ -59,54 +62,130 @@ static void zero_out_btree_mem_ptr(struct journal_keys *keys)
 static int __journal_key_cmp(enum btree_id     l_btree_id,
                             unsigned           l_level,
                             struct bpos        l_pos,
-                            struct journal_key *r)
+                            const struct journal_key *r)
 {
        return (cmp_int(l_btree_id,     r->btree_id) ?:
                cmp_int(l_level,        r->level) ?:
                bpos_cmp(l_pos, r->k->k.p));
 }
 
-static int journal_key_cmp(struct journal_key *l, struct journal_key *r)
+static int journal_key_cmp(const struct journal_key *l, const struct journal_key *r)
 {
-       return (cmp_int(l->btree_id,    r->btree_id) ?:
-               cmp_int(l->level,       r->level) ?:
-               bpos_cmp(l->k->k.p,     r->k->k.p));
+       return __journal_key_cmp(l->btree_id, l->level, l->k->k.p, r);
 }
 
-static size_t journal_key_search(struct journal_keys *journal_keys,
-                                enum btree_id id, unsigned level,
-                                struct bpos pos)
+static inline size_t idx_to_pos(struct journal_keys *keys, size_t idx)
 {
-       size_t l = 0, r = journal_keys->nr, m;
+       size_t gap_size = keys->size - keys->nr;
+
+       if (idx >= keys->gap)
+               idx += gap_size;
+       return idx;
+}
+
+static inline struct journal_key *idx_to_key(struct journal_keys *keys, size_t idx)
+{
+       return keys->d + idx_to_pos(keys, idx);
+}
+
+static size_t __bch2_journal_key_search(struct journal_keys *keys,
+                                       enum btree_id id, unsigned level,
+                                       struct bpos pos)
+{
+       size_t l = 0, r = keys->nr, m;
 
        while (l < r) {
                m = l + ((r - l) >> 1);
-               if (__journal_key_cmp(id, level, pos, &journal_keys->d[m]) > 0)
+               if (__journal_key_cmp(id, level, pos, idx_to_key(keys, m)) > 0)
                        l = m + 1;
                else
                        r = m;
        }
 
-       BUG_ON(l < journal_keys->nr &&
-              __journal_key_cmp(id, level, pos, &journal_keys->d[l]) > 0);
+       BUG_ON(l < keys->nr &&
+              __journal_key_cmp(id, level, pos, idx_to_key(keys, l)) > 0);
 
        BUG_ON(l &&
-              __journal_key_cmp(id, level, pos, &journal_keys->d[l - 1]) <= 0);
+              __journal_key_cmp(id, level, pos, idx_to_key(keys, l - 1)) <= 0);
 
        return l;
 }
 
-static void journal_iter_fix(struct bch_fs *c, struct journal_iter *iter, unsigned idx)
+static size_t bch2_journal_key_search(struct journal_keys *keys,
+                                     enum btree_id id, unsigned level,
+                                     struct bpos pos)
 {
-       struct bkey_i *n = iter->keys->d[idx].k;
-       struct btree_and_journal_iter *biter =
-               container_of(iter, struct btree_and_journal_iter, journal);
-
-       if (iter->idx > idx ||
-           (iter->idx == idx &&
-            biter->last &&
-            bpos_cmp(n->k.p, biter->unpacked.p) <= 0))
-               iter->idx++;
+       return idx_to_pos(keys, __bch2_journal_key_search(keys, id, level, pos));
+}
+
+struct bkey_i *bch2_journal_keys_peek_upto(struct bch_fs *c, enum btree_id btree_id,
+                                          unsigned level, struct bpos pos,
+                                          struct bpos end_pos, size_t *idx)
+{
+       struct journal_keys *keys = &c->journal_keys;
+       unsigned iters = 0;
+       struct journal_key *k;
+search:
+       if (!*idx)
+               *idx = __bch2_journal_key_search(keys, btree_id, level, pos);
+
+       while ((k = *idx < keys->nr ? idx_to_key(keys, *idx) : NULL)) {
+               if (__journal_key_cmp(btree_id, level, end_pos, k) < 0)
+                       return NULL;
+
+               if (__journal_key_cmp(btree_id, level, pos, k) <= 0 &&
+                   !k->overwritten)
+                       return k->k;
+
+               (*idx)++;
+               iters++;
+               if (iters == 10) {
+                       *idx = 0;
+                       goto search;
+               }
+       }
+
+       return NULL;
+}
+
+struct bkey_i *bch2_journal_keys_peek_slot(struct bch_fs *c, enum btree_id btree_id,
+                                          unsigned level, struct bpos pos)
+{
+       size_t idx = 0;
+
+       return bch2_journal_keys_peek_upto(c, btree_id, level, pos, pos, &idx);
+}
+
+static void journal_iters_fix(struct bch_fs *c)
+{
+       struct journal_keys *keys = &c->journal_keys;
+       /* The key we just inserted is immediately before the gap: */
+       size_t gap_end = keys->gap + (keys->size - keys->nr);
+       struct btree_and_journal_iter *iter;
+
+       /*
+        * If an iterator points one after the key we just inserted, decrement
+        * the iterator so it points at the key we just inserted - if the
+        * decrement was unnecessary, bch2_btree_and_journal_iter_peek() will
+        * handle that:
+        */
+       list_for_each_entry(iter, &c->journal_iters, journal.list)
+               if (iter->journal.idx == gap_end)
+                       iter->journal.idx = keys->gap - 1;
+}
+
+static void journal_iters_move_gap(struct bch_fs *c, size_t old_gap, size_t new_gap)
+{
+       struct journal_keys *keys = &c->journal_keys;
+       struct journal_iter *iter;
+       size_t gap_size = keys->size - keys->nr;
+
+       list_for_each_entry(iter, &c->journal_iters, list) {
+               if (iter->idx > old_gap)
+                       iter->idx -= gap_size;
+               if (iter->idx >= new_gap)
+                       iter->idx += gap_size;
+       }
 }
 
 int bch2_journal_key_insert_take(struct bch_fs *c, enum btree_id id,
@@ -116,13 +195,19 @@ int bch2_journal_key_insert_take(struct bch_fs *c, enum btree_id id,
                .btree_id       = id,
                .level          = level,
                .k              = k,
-               .allocated      = true
+               .allocated      = true,
+               /*
+                * Ensure these keys are done last by journal replay, to unblock
+                * journal reclaim:
+                */
+               .journal_seq    = U32_MAX,
        };
        struct journal_keys *keys = &c->journal_keys;
-       struct journal_iter *iter;
-       unsigned idx = journal_key_search(keys, id, level, k->k.p);
+       size_t idx = bch2_journal_key_search(keys, id, level, k->k.p);
+
+       BUG_ON(test_bit(BCH_FS_RW, &c->flags));
 
-       if (idx < keys->nr &&
+       if (idx < keys->size &&
            journal_key_cmp(&n, &keys->d[idx]) == 0) {
                if (keys->d[idx].allocated)
                        kfree(keys->d[idx].k);
@@ -130,33 +215,49 @@ int bch2_journal_key_insert_take(struct bch_fs *c, enum btree_id id,
                return 0;
        }
 
+       if (idx > keys->gap)
+               idx -= keys->size - keys->nr;
+
        if (keys->nr == keys->size) {
                struct journal_keys new_keys = {
                        .nr                     = keys->nr,
-                       .size                   = keys->size * 2,
-                       .journal_seq_base       = keys->journal_seq_base,
+                       .size                   = max_t(size_t, keys->size, 8) * 2,
                };
 
-               new_keys.d = kvmalloc(sizeof(new_keys.d[0]) * new_keys.size, GFP_KERNEL);
+               new_keys.d = kvmalloc_array(new_keys.size, sizeof(new_keys.d[0]), GFP_KERNEL);
                if (!new_keys.d) {
                        bch_err(c, "%s: error allocating new key array (size %zu)",
                                __func__, new_keys.size);
-                       return -ENOMEM;
+                       return -BCH_ERR_ENOMEM_journal_key_insert;
                }
 
+               /* Since @keys was full, there was no gap: */
                memcpy(new_keys.d, keys->d, sizeof(keys->d[0]) * keys->nr);
                kvfree(keys->d);
                *keys = new_keys;
+
+               /* And now the gap is at the end: */
+               keys->gap = keys->nr;
        }
 
-       array_insert_item(keys->d, keys->nr, idx, n);
+       journal_iters_move_gap(c, keys->gap, idx);
+
+       move_gap(keys->d, keys->nr, keys->size, keys->gap, idx);
+       keys->gap = idx;
 
-       list_for_each_entry(iter, &c->journal_iters, list)
-               journal_iter_fix(c, iter, idx);
+       keys->nr++;
+       keys->d[keys->gap++] = n;
+
+       journal_iters_fix(c);
 
        return 0;
 }
 
+/*
+ * Can only be used from the recovery thread while we're still RO - can't be
+ * used once we've got RW, as journal_keys is at that point used by multiple
+ * threads:
+ */
 int bch2_journal_key_insert(struct bch_fs *c, enum btree_id id,
                            unsigned level, struct bkey_i *k)
 {
@@ -165,7 +266,7 @@ int bch2_journal_key_insert(struct bch_fs *c, enum btree_id id,
 
        n = kmalloc(bkey_bytes(&k->k), GFP_KERNEL);
        if (!n)
-               return -ENOMEM;
+               return -BCH_ERR_ENOMEM_journal_key_insert;
 
        bkey_copy(n, k);
        ret = bch2_journal_key_insert_take(c, id, level, n);
@@ -185,24 +286,43 @@ int bch2_journal_key_delete(struct bch_fs *c, enum btree_id id,
        return bch2_journal_key_insert(c, id, level, &whiteout);
 }
 
-static struct bkey_i *bch2_journal_iter_peek(struct journal_iter *iter)
+void bch2_journal_key_overwritten(struct bch_fs *c, enum btree_id btree,
+                                 unsigned level, struct bpos pos)
 {
-       struct journal_key *k = iter->idx - iter->keys->nr
-               ? iter->keys->d + iter->idx : NULL;
-
-       if (k &&
-           k->btree_id == iter->btree_id &&
-           k->level    == iter->level)
-               return k->k;
+       struct journal_keys *keys = &c->journal_keys;
+       size_t idx = bch2_journal_key_search(keys, btree, level, pos);
 
-       iter->idx = iter->keys->nr;
-       return NULL;
+       if (idx < keys->size &&
+           keys->d[idx].btree_id       == btree &&
+           keys->d[idx].level          == level &&
+           bpos_eq(keys->d[idx].k->k.p, pos))
+               keys->d[idx].overwritten = true;
 }
 
 static void bch2_journal_iter_advance(struct journal_iter *iter)
 {
-       if (iter->idx < iter->keys->nr)
+       if (iter->idx < iter->keys->size) {
                iter->idx++;
+               if (iter->idx == iter->keys->gap)
+                       iter->idx += iter->keys->size - iter->keys->nr;
+       }
+}
+
+struct bkey_s_c bch2_journal_iter_peek(struct journal_iter *iter)
+{
+       struct journal_key *k = iter->keys->d + iter->idx;
+
+       while (k < iter->keys->d + iter->keys->size &&
+              k->btree_id      == iter->btree_id &&
+              k->level         == iter->level) {
+               if (!k->overwritten)
+                       return bkey_i_to_s_c(k->k);
+
+               bch2_journal_iter_advance(iter);
+               k = iter->keys->d + iter->idx;
+       }
+
+       return bkey_s_c_null;
 }
 
 static void bch2_journal_iter_exit(struct journal_iter *iter)
@@ -218,8 +338,7 @@ static void bch2_journal_iter_init(struct bch_fs *c,
        iter->btree_id  = id;
        iter->level     = level;
        iter->keys      = &c->journal_keys;
-       iter->idx       = journal_key_search(&c->journal_keys, id, level, pos);
-       list_add(&iter->list, &c->journal_iters);
+       iter->idx       = bch2_journal_key_search(&c->journal_keys, id, level, pos);
 }
 
 static struct bkey_s_c bch2_journal_iter_peek_btree(struct btree_and_journal_iter *iter)
@@ -235,190 +354,97 @@ static void bch2_journal_iter_advance_btree(struct btree_and_journal_iter *iter)
 
 void bch2_btree_and_journal_iter_advance(struct btree_and_journal_iter *iter)
 {
-       switch (iter->last) {
-       case none:
-               break;
-       case btree:
-               bch2_journal_iter_advance_btree(iter);
-               break;
-       case journal:
-               bch2_journal_iter_advance(&iter->journal);
-               break;
-       }
-
-       iter->last = none;
+       if (bpos_eq(iter->pos, SPOS_MAX))
+               iter->at_end = true;
+       else
+               iter->pos = bpos_successor(iter->pos);
 }
 
 struct bkey_s_c bch2_btree_and_journal_iter_peek(struct btree_and_journal_iter *iter)
 {
-       struct bkey_s_c ret;
-
-       while (1) {
-               struct bkey_s_c btree_k         =
-                       bch2_journal_iter_peek_btree(iter);
-               struct bkey_s_c journal_k       =
-                       bkey_i_to_s_c(bch2_journal_iter_peek(&iter->journal));
+       struct bkey_s_c btree_k, journal_k, ret;
+again:
+       if (iter->at_end)
+               return bkey_s_c_null;
 
-               if (btree_k.k && journal_k.k) {
-                       int cmp = bpos_cmp(btree_k.k->p, journal_k.k->p);
+       while ((btree_k = bch2_journal_iter_peek_btree(iter)).k &&
+              bpos_lt(btree_k.k->p, iter->pos))
+               bch2_journal_iter_advance_btree(iter);
 
-                       if (!cmp)
-                               bch2_journal_iter_advance_btree(iter);
+       while ((journal_k = bch2_journal_iter_peek(&iter->journal)).k &&
+              bpos_lt(journal_k.k->p, iter->pos))
+               bch2_journal_iter_advance(&iter->journal);
 
-                       iter->last = cmp < 0 ? btree : journal;
-               } else if (btree_k.k) {
-                       iter->last = btree;
-               } else if (journal_k.k) {
-                       iter->last = journal;
-               } else {
-                       iter->last = none;
-                       return bkey_s_c_null;
-               }
+       ret = journal_k.k &&
+               (!btree_k.k || bpos_le(journal_k.k->p, btree_k.k->p))
+               ? journal_k
+               : btree_k;
 
-               ret = iter->last == journal ? journal_k : btree_k;
+       if (ret.k && iter->b && bpos_gt(ret.k->p, iter->b->data->max_key))
+               ret = bkey_s_c_null;
 
-               if (iter->b &&
-                   bpos_cmp(ret.k->p, iter->b->data->max_key) > 0) {
-                       iter->journal.idx = iter->journal.keys->nr;
-                       iter->last = none;
-                       return bkey_s_c_null;
+       if (ret.k) {
+               iter->pos = ret.k->p;
+               if (bkey_deleted(ret.k)) {
+                       bch2_btree_and_journal_iter_advance(iter);
+                       goto again;
                }
-
-               if (!bkey_deleted(ret.k))
-                       break;
-
-               bch2_btree_and_journal_iter_advance(iter);
+       } else {
+               iter->pos = SPOS_MAX;
+               iter->at_end = true;
        }
 
        return ret;
 }
 
-struct bkey_s_c bch2_btree_and_journal_iter_next(struct btree_and_journal_iter *iter)
-{
-       bch2_btree_and_journal_iter_advance(iter);
-
-       return bch2_btree_and_journal_iter_peek(iter);
-}
-
 void bch2_btree_and_journal_iter_exit(struct btree_and_journal_iter *iter)
 {
        bch2_journal_iter_exit(&iter->journal);
 }
 
-void bch2_btree_and_journal_iter_init_node_iter(struct btree_and_journal_iter *iter,
-                                               struct bch_fs *c,
-                                               struct btree *b)
+void __bch2_btree_and_journal_iter_init_node_iter(struct btree_and_journal_iter *iter,
+                                                 struct bch_fs *c,
+                                                 struct btree *b,
+                                                 struct btree_node_iter node_iter,
+                                                 struct bpos pos)
 {
        memset(iter, 0, sizeof(*iter));
 
        iter->b = b;
-       bch2_btree_node_iter_init_from_start(&iter->node_iter, iter->b);
-       bch2_journal_iter_init(c, &iter->journal,
-                              b->c.btree_id, b->c.level, b->data->min_key);
+       iter->node_iter = node_iter;
+       bch2_journal_iter_init(c, &iter->journal, b->c.btree_id, b->c.level, pos);
+       INIT_LIST_HEAD(&iter->journal.list);
+       iter->pos = b->data->min_key;
+       iter->at_end = false;
 }
 
-/* Walk btree, overlaying keys from the journal: */
-
-static void btree_and_journal_iter_prefetch(struct bch_fs *c, struct btree *b,
-                                          struct btree_and_journal_iter iter)
-{
-       unsigned i = 0, nr = b->c.level > 1 ? 2 : 16;
-       struct bkey_s_c k;
-       struct bkey_buf tmp;
-
-       BUG_ON(!b->c.level);
-
-       bch2_bkey_buf_init(&tmp);
-
-       while (i < nr &&
-              (k = bch2_btree_and_journal_iter_peek(&iter)).k) {
-               bch2_bkey_buf_reassemble(&tmp, c, k);
-
-               bch2_btree_node_prefetch(c, NULL, NULL, tmp.k,
-                                       b->c.btree_id, b->c.level - 1);
-
-               bch2_btree_and_journal_iter_advance(&iter);
-               i++;
-       }
-
-       bch2_bkey_buf_exit(&tmp, c);
-}
-
-static int bch2_btree_and_journal_walk_recurse(struct btree_trans *trans, struct btree *b,
-                               enum btree_id btree_id,
-                               btree_walk_key_fn key_fn)
-{
-       struct bch_fs *c = trans->c;
-       struct btree_and_journal_iter iter;
-       struct bkey_s_c k;
-       struct bkey_buf tmp;
-       struct btree *child;
-       int ret = 0;
-
-       bch2_bkey_buf_init(&tmp);
-       bch2_btree_and_journal_iter_init_node_iter(&iter, c, b);
-
-       while ((k = bch2_btree_and_journal_iter_peek(&iter)).k) {
-               if (b->c.level) {
-                       bch2_bkey_buf_reassemble(&tmp, c, k);
-
-                       child = bch2_btree_node_get_noiter(c, tmp.k,
-                                               b->c.btree_id, b->c.level - 1,
-                                               false);
-
-                       ret = PTR_ERR_OR_ZERO(child);
-                       if (ret)
-                               break;
-
-                       btree_and_journal_iter_prefetch(c, b, iter);
-
-                       ret = bch2_btree_and_journal_walk_recurse(trans, child,
-                                       btree_id, key_fn);
-                       six_unlock_read(&child->c.lock);
-               } else {
-                       ret = key_fn(trans, k);
-               }
-
-               if (ret)
-                       break;
-
-               bch2_btree_and_journal_iter_advance(&iter);
-       }
-
-       bch2_btree_and_journal_iter_exit(&iter);
-       bch2_bkey_buf_exit(&tmp, c);
-       return ret;
-}
-
-int bch2_btree_and_journal_walk(struct btree_trans *trans, enum btree_id btree_id,
-                               btree_walk_key_fn key_fn)
+/*
+ * this version is used by btree_gc before filesystem has gone RW and
+ * multithreaded, so uses the journal_iters list:
+ */
+void bch2_btree_and_journal_iter_init_node_iter(struct btree_and_journal_iter *iter,
+                                               struct bch_fs *c,
+                                               struct btree *b)
 {
-       struct bch_fs *c = trans->c;
-       struct btree *b = c->btree_roots[btree_id].b;
-       int ret = 0;
-
-       if (btree_node_fake(b))
-               return 0;
-
-       six_lock_read(&b->c.lock, NULL, NULL);
-       ret = bch2_btree_and_journal_walk_recurse(trans, b, btree_id, key_fn);
-       six_unlock_read(&b->c.lock);
+       struct btree_node_iter node_iter;
 
-       return ret;
+       bch2_btree_node_iter_init_from_start(&node_iter, b);
+       __bch2_btree_and_journal_iter_init_node_iter(iter, c, b, node_iter, b->data->min_key);
+       list_add(&iter->journal.list, &c->journal_iters);
 }
 
 /* sort and dedup all keys in the journal: */
 
-void bch2_journal_entries_free(struct list_head *list)
+void bch2_journal_entries_free(struct bch_fs *c)
 {
-
-       while (!list_empty(list)) {
-               struct journal_replay *i =
-                       list_first_entry(list, struct journal_replay, list);
-               list_del(&i->list);
-               kvpfree(i, offsetof(struct journal_replay, j) +
-                       vstruct_bytes(&i->j));
-       }
+       struct journal_replay **i;
+       struct genradix_iter iter;
+
+       genradix_for_each(&c->journal_entries, iter, i)
+               if (*i)
+                       kvpfree(*i, offsetof(struct journal_replay, j) +
+                               vstruct_bytes(&(*i)->j));
+       genradix_free(&c->journal_entries);
 }
 
 /*
@@ -429,9 +455,7 @@ static int journal_sort_key_cmp(const void *_l, const void *_r)
        const struct journal_key *l = _l;
        const struct journal_key *r = _r;
 
-       return  cmp_int(l->btree_id,    r->btree_id) ?:
-               cmp_int(l->level,       r->level) ?:
-               bpos_cmp(l->k->k.p, r->k->k.p) ?:
+       return  journal_key_cmp(l, r) ?:
                cmp_int(l->journal_seq, r->journal_seq) ?:
                cmp_int(l->journal_offset, r->journal_offset);
 }
@@ -440,77 +464,115 @@ void bch2_journal_keys_free(struct journal_keys *keys)
 {
        struct journal_key *i;
 
+       move_gap(keys->d, keys->nr, keys->size, keys->gap, keys->nr);
+       keys->gap = keys->nr;
+
        for (i = keys->d; i < keys->d + keys->nr; i++)
                if (i->allocated)
                        kfree(i->k);
 
        kvfree(keys->d);
        keys->d = NULL;
-       keys->nr = 0;
+       keys->nr = keys->gap = keys->size = 0;
 }
 
-static struct journal_keys journal_keys_sort(struct list_head *journal_entries)
+static void __journal_keys_sort(struct journal_keys *keys)
 {
-       struct journal_replay *i;
-       struct jset_entry *entry;
-       struct bkey_i *k, *_n;
-       struct journal_keys keys = { NULL };
        struct journal_key *src, *dst;
-       size_t nr_keys = 0;
 
-       if (list_empty(journal_entries))
-               return keys;
+       sort(keys->d, keys->nr, sizeof(keys->d[0]), journal_sort_key_cmp, NULL);
 
-       list_for_each_entry(i, journal_entries, list) {
-               if (i->ignore)
-                       continue;
+       src = dst = keys->d;
+       while (src < keys->d + keys->nr) {
+               while (src + 1 < keys->d + keys->nr &&
+                      src[0].btree_id  == src[1].btree_id &&
+                      src[0].level     == src[1].level &&
+                      bpos_eq(src[0].k->k.p, src[1].k->k.p))
+                       src++;
 
-               if (!keys.journal_seq_base)
-                       keys.journal_seq_base = le64_to_cpu(i->j.seq);
+               *dst++ = *src++;
+       }
 
-               for_each_jset_key(k, _n, entry, &i->j)
+       keys->nr = dst - keys->d;
+}
+
+static int journal_keys_sort(struct bch_fs *c)
+{
+       struct genradix_iter iter;
+       struct journal_replay *i, **_i;
+       struct jset_entry *entry;
+       struct bkey_i *k;
+       struct journal_keys *keys = &c->journal_keys;
+       size_t nr_keys = 0, nr_read = 0;
+
+       genradix_for_each(&c->journal_entries, iter, _i) {
+               i = *_i;
+
+               if (!i || i->ignore)
+                       continue;
+
+               for_each_jset_key(k, entry, &i->j)
                        nr_keys++;
        }
 
-       keys.size = roundup_pow_of_two(nr_keys);
+       if (!nr_keys)
+               return 0;
 
-       keys.d = kvmalloc(sizeof(keys.d[0]) * keys.size, GFP_KERNEL);
-       if (!keys.d)
-               goto err;
+       keys->size = roundup_pow_of_two(nr_keys);
+
+       keys->d = kvmalloc_array(keys->size, sizeof(keys->d[0]), GFP_KERNEL);
+       if (!keys->d) {
+               bch_err(c, "Failed to allocate buffer for sorted journal keys (%zu keys); trying slowpath",
+                       nr_keys);
+
+               do {
+                       keys->size >>= 1;
+                       keys->d = kvmalloc_array(keys->size, sizeof(keys->d[0]), GFP_KERNEL);
+               } while (!keys->d && keys->size > nr_keys / 8);
+
+               if (!keys->d) {
+                       bch_err(c, "Failed to allocate %zu size buffer for sorted journal keys; exiting",
+                               keys->size);
+                       return -BCH_ERR_ENOMEM_journal_keys_sort;
+               }
+       }
+
+       genradix_for_each(&c->journal_entries, iter, _i) {
+               i = *_i;
 
-       list_for_each_entry(i, journal_entries, list) {
-               if (i->ignore)
+               if (!i || i->ignore)
                        continue;
 
-               BUG_ON(le64_to_cpu(i->j.seq) - keys.journal_seq_base > U32_MAX);
+               cond_resched();
+
+               for_each_jset_key(k, entry, &i->j) {
+                       if (keys->nr == keys->size) {
+                               __journal_keys_sort(keys);
 
-               for_each_jset_key(k, _n, entry, &i->j)
-                       keys.d[keys.nr++] = (struct journal_key) {
+                               if (keys->nr > keys->size * 7 / 8) {
+                                       bch_err(c, "Too many journal keys for slowpath; have %zu compacted, buf size %zu, processed %zu/%zu",
+                                               keys->nr, keys->size, nr_read, nr_keys);
+                                       return -BCH_ERR_ENOMEM_journal_keys_sort;
+                               }
+                       }
+
+                       keys->d[keys->nr++] = (struct journal_key) {
                                .btree_id       = entry->btree_id,
                                .level          = entry->level,
                                .k              = k,
-                               .journal_seq    = le64_to_cpu(i->j.seq) -
-                                       keys.journal_seq_base,
+                               .journal_seq    = le64_to_cpu(i->j.seq),
                                .journal_offset = k->_data - i->j._data,
                        };
-       }
-
-       sort(keys.d, keys.nr, sizeof(keys.d[0]), journal_sort_key_cmp, NULL);
 
-       src = dst = keys.d;
-       while (src < keys.d + keys.nr) {
-               while (src + 1 < keys.d + keys.nr &&
-                      src[0].btree_id  == src[1].btree_id &&
-                      src[0].level     == src[1].level &&
-                      !bpos_cmp(src[0].k->k.p, src[1].k->k.p))
-                       src++;
-
-               *dst++ = *src++;
+                       nr_read++;
+               }
        }
 
-       keys.nr = dst - keys.d;
-err:
-       return keys;
+       __journal_keys_sort(keys);
+       keys->gap = keys->nr;
+
+       bch_verbose(c, "Journal keys: %zu read, %zu after sorting and compacting", nr_keys, keys->nr);
+       return 0;
 }
 
 /* journal replay: */
@@ -518,14 +580,15 @@ err:
 static void replay_now_at(struct journal *j, u64 seq)
 {
        BUG_ON(seq < j->replay_journal_seq);
-       BUG_ON(seq > j->replay_journal_seq_end);
+
+       seq = min(seq, j->replay_journal_seq_end);
 
        while (j->replay_journal_seq < seq)
                bch2_journal_pin_put(j, j->replay_journal_seq++);
 }
 
-static int __bch2_journal_replay_key(struct btree_trans *trans,
-                                    struct journal_key *k)
+static int bch2_journal_replay_key(struct btree_trans *trans,
+                                  struct journal_key *k)
 {
        struct btree_iter iter;
        unsigned iter_flags =
@@ -534,29 +597,23 @@ static int __bch2_journal_replay_key(struct btree_trans *trans,
        int ret;
 
        if (!k->level && k->btree_id == BTREE_ID_alloc)
-               iter_flags |= BTREE_ITER_CACHED|BTREE_ITER_CACHED_NOFILL;
+               iter_flags |= BTREE_ITER_CACHED;
 
        bch2_trans_node_iter_init(trans, &iter, k->btree_id, k->k->k.p,
                                  BTREE_MAX_DEPTH, k->level,
                                  iter_flags);
-       ret   = bch2_btree_iter_traverse(&iter) ?:
-               bch2_trans_update(trans, &iter, k->k, BTREE_TRIGGER_NORUN);
-       bch2_trans_iter_exit(trans, &iter);
-       return ret;
-}
-
-static int bch2_journal_replay_key(struct bch_fs *c, struct journal_key *k)
-{
-       unsigned commit_flags =
-               BTREE_INSERT_LAZY_RW|
-               BTREE_INSERT_NOFAIL|
-               BTREE_INSERT_JOURNAL_RESERVED;
+       ret = bch2_btree_iter_traverse(&iter);
+       if (ret)
+               goto out;
 
-       if (!k->allocated)
-               commit_flags |= BTREE_INSERT_JOURNAL_REPLAY;
+       /* Must be checked with btree locked: */
+       if (k->overwritten)
+               goto out;
 
-       return bch2_trans_do(c, NULL, NULL, commit_flags,
-                            __bch2_journal_replay_key(&trans, k));
+       ret = bch2_trans_update(trans, &iter, k->k, BTREE_TRIGGER_NORUN);
+out:
+       bch2_trans_iter_exit(trans, &iter);
+       return ret;
 }
 
 static int journal_sort_seq_cmp(const void *_l, const void *_r)
@@ -564,26 +621,23 @@ static int journal_sort_seq_cmp(const void *_l, const void *_r)
        const struct journal_key *l = *((const struct journal_key **)_l);
        const struct journal_key *r = *((const struct journal_key **)_r);
 
-       return  cmp_int(r->level,       l->level) ?:
-               cmp_int(l->journal_seq, r->journal_seq) ?:
-               cmp_int(l->btree_id,    r->btree_id) ?:
-               bpos_cmp(l->k->k.p,     r->k->k.p);
+       return cmp_int(l->journal_seq, r->journal_seq);
 }
 
-static int bch2_journal_replay(struct bch_fs *c)
+static int bch2_journal_replay(struct bch_fs *c, u64 start_seq, u64 end_seq)
 {
        struct journal_keys *keys = &c->journal_keys;
        struct journal_key **keys_sorted, *k;
        struct journal *j = &c->journal;
-       struct bch_dev *ca;
-       unsigned idx;
        size_t i;
-       u64 seq;
        int ret;
 
-       keys_sorted = kmalloc_array(sizeof(*keys_sorted), keys->nr, GFP_KERNEL);
+       move_gap(keys->d, keys->nr, keys->size, keys->gap, keys->nr);
+       keys->gap = keys->nr;
+
+       keys_sorted = kvmalloc_array(sizeof(*keys_sorted), keys->nr, GFP_KERNEL);
        if (!keys_sorted)
-               return -ENOMEM;
+               return -BCH_ERR_ENOMEM_journal_replay;
 
        for (i = 0; i < keys->nr; i++)
                keys_sorted[i] = &keys->d[i];
@@ -592,76 +646,32 @@ static int bch2_journal_replay(struct bch_fs *c)
             sizeof(keys_sorted[0]),
             journal_sort_seq_cmp, NULL);
 
-       if (keys->nr)
-               replay_now_at(j, keys->journal_seq_base);
-
-       seq = j->replay_journal_seq;
-
-       /*
-        * First replay updates to the alloc btree - these will only update the
-        * btree key cache:
-        */
-       for (i = 0; i < keys->nr; i++) {
-               k = keys_sorted[i];
-
-               cond_resched();
-
-               if (!k->level && k->btree_id == BTREE_ID_alloc) {
-                       j->replay_journal_seq = keys->journal_seq_base + k->journal_seq;
-                       ret = bch2_journal_replay_key(c, k);
-                       if (ret)
-                               goto err;
-               }
-       }
-
-       /* Now we can start the allocator threads: */
-       set_bit(BCH_FS_ALLOC_REPLAY_DONE, &c->flags);
-       for_each_member_device(ca, c, idx)
-               bch2_wake_allocator(ca);
-
-       /*
-        * Next replay updates to interior btree nodes:
-        */
-       for (i = 0; i < keys->nr; i++) {
-               k = keys_sorted[i];
-
-               cond_resched();
-
-               if (k->level) {
-                       j->replay_journal_seq = keys->journal_seq_base + k->journal_seq;
-                       ret = bch2_journal_replay_key(c, k);
-                       if (ret)
-                               goto err;
-               }
+       if (keys->nr) {
+               ret = bch2_journal_log_msg(c, "Starting journal replay (%zu keys in entries %llu-%llu)",
+                                          keys->nr, start_seq, end_seq);
+               if (ret)
+                       goto err;
        }
 
-       /*
-        * Now that the btree is in a consistent state, we can start journal
-        * reclaim (which will be flushing entries from the btree key cache back
-        * to the btree:
-        */
-       set_bit(BCH_FS_BTREE_INTERIOR_REPLAY_DONE, &c->flags);
-       set_bit(JOURNAL_RECLAIM_STARTED, &j->flags);
-       journal_reclaim_kick(j);
-
-       j->replay_journal_seq = seq;
-
-       /*
-        * Now replay leaf node updates:
-        */
        for (i = 0; i < keys->nr; i++) {
                k = keys_sorted[i];
 
                cond_resched();
 
-               if (k->level || k->btree_id == BTREE_ID_alloc)
-                       continue;
-
-               replay_now_at(j, keys->journal_seq_base + k->journal_seq);
+               replay_now_at(j, k->journal_seq);
 
-               ret = bch2_journal_replay_key(c, k);
-               if (ret)
+               ret = bch2_trans_do(c, NULL, NULL,
+                                   BTREE_INSERT_LAZY_RW|
+                                   BTREE_INSERT_NOFAIL|
+                                   (!k->allocated
+                                    ? BTREE_INSERT_JOURNAL_REPLAY|JOURNAL_WATERMARK_reserved
+                                    : 0),
+                            bch2_journal_replay_key(&trans, k));
+               if (ret) {
+                       bch_err(c, "journal replay: error while replaying key at btree %s level %u: %s",
+                               bch2_btree_ids[k->btree_id], k->level, bch2_err_str(ret));
                        goto err;
+               }
        }
 
        replay_now_at(j, j->replay_journal_seq_end);
@@ -669,14 +679,12 @@ static int bch2_journal_replay(struct bch_fs *c)
 
        bch2_journal_set_replay_done(j);
        bch2_journal_flush_all_pins(j);
-       kfree(keys_sorted);
+       ret = bch2_journal_error(j);
 
-       return bch2_journal_error(j);
+       if (keys->nr && !ret)
+               bch2_journal_log_msg(c, "journal replay finished");
 err:
-       bch_err(c, "journal replay: error %d while replaying key at btree %s level %u",
-               ret, bch2_btree_ids[k->btree_id], k->level);
-       kfree(keys_sorted);
-
+       kvfree(keys_sorted);
        return ret;
 }
 
@@ -714,15 +722,15 @@ static int journal_replay_entry_early(struct bch_fs *c,
                        container_of(entry, struct jset_entry_usage, entry);
 
                switch (entry->btree_id) {
-               case FS_USAGE_RESERVED:
+               case BCH_FS_USAGE_reserved:
                        if (entry->level < BCH_REPLICAS_MAX)
                                c->usage_base->persistent_reserved[entry->level] =
                                        le64_to_cpu(u->v);
                        break;
-               case FS_USAGE_INODES:
+               case BCH_FS_USAGE_inodes:
                        c->usage_base->nr_inodes = le64_to_cpu(u->v);
                        break;
-               case FS_USAGE_KEY_VERSION:
+               case BCH_FS_USAGE_key_version:
                        atomic64_set(&c->key_version,
                                     le64_to_cpu(u->v));
                        break;
@@ -742,13 +750,9 @@ static int journal_replay_entry_early(struct bch_fs *c,
                struct jset_entry_dev_usage *u =
                        container_of(entry, struct jset_entry_dev_usage, entry);
                struct bch_dev *ca = bch_dev_bkey_exists(c, le32_to_cpu(u->dev));
-               unsigned bytes = jset_u64s(le16_to_cpu(entry->u64s)) * sizeof(u64);
-               unsigned nr_types = (bytes - sizeof(struct jset_entry_dev_usage)) /
-                       sizeof(struct jset_entry_dev_usage_type);
-               unsigned i;
+               unsigned i, nr_types = jset_entry_dev_usage_nr_types(u);
 
                ca->usage_base->buckets_ec              = le64_to_cpu(u->buckets_ec);
-               ca->usage_base->buckets_unavailable     = le64_to_cpu(u->buckets_unavailable);
 
                for (i = 0; i < min_t(unsigned, nr_types, BCH_DATA_NR); i++) {
                        ca->usage_base->d[i].buckets    = le64_to_cpu(u->d[i].buckets);
@@ -788,10 +792,8 @@ static int journal_replay_entry_early(struct bch_fs *c,
 }
 
 static int journal_replay_early(struct bch_fs *c,
-                               struct bch_sb_field_clean *clean,
-                               struct list_head *journal)
+                               struct bch_sb_field_clean *clean)
 {
-       struct journal_replay *i;
        struct jset_entry *entry;
        int ret;
 
@@ -804,8 +806,13 @@ static int journal_replay_early(struct bch_fs *c,
                                return ret;
                }
        } else {
-               list_for_each_entry(i, journal, list) {
-                       if (i->ignore)
+               struct genradix_iter iter;
+               struct journal_replay *i, **_i;
+
+               genradix_for_each(&c->journal_entries, iter, _i) {
+                       i = *_i;
+
+                       if (!i || i->ignore)
                                continue;
 
                        vstruct_for_each(&i->j, entry) {
@@ -860,6 +867,8 @@ static int verify_superblock_clean(struct bch_fs *c,
 {
        unsigned i;
        struct bch_sb_field_clean *clean = *cleanp;
+       struct printbuf buf1 = PRINTBUF;
+       struct printbuf buf2 = PRINTBUF;
        int ret = 0;
 
        if (mustfix_fsck_err_on(j->seq != clean->journal_seq, c,
@@ -872,7 +881,6 @@ static int verify_superblock_clean(struct bch_fs *c,
        }
 
        for (i = 0; i < BTREE_ID_NR; i++) {
-               char buf1[200], buf2[200];
                struct bkey_i *k1, *k2;
                unsigned l1 = 0, l2 = 0;
 
@@ -882,19 +890,34 @@ static int verify_superblock_clean(struct bch_fs *c,
                if (!k1 && !k2)
                        continue;
 
+               printbuf_reset(&buf1);
+               printbuf_reset(&buf2);
+
+               if (k1)
+                       bch2_bkey_val_to_text(&buf1, c, bkey_i_to_s_c(k1));
+               else
+                       prt_printf(&buf1, "(none)");
+
+               if (k2)
+                       bch2_bkey_val_to_text(&buf2, c, bkey_i_to_s_c(k2));
+               else
+                       prt_printf(&buf2, "(none)");
+
                mustfix_fsck_err_on(!k1 || !k2 ||
                                    IS_ERR(k1) ||
                                    IS_ERR(k2) ||
                                    k1->k.u64s != k2->k.u64s ||
-                                   memcmp(k1, k2, bkey_bytes(k1)) ||
+                                   memcmp(k1, k2, bkey_bytes(&k1->k)) ||
                                    l1 != l2, c,
                        "superblock btree root %u doesn't match journal after clean shutdown\n"
                        "sb:      l=%u %s\n"
                        "journal: l=%u %s\n", i,
-                       l1, (bch2_bkey_val_to_text(&PBUF(buf1), c, bkey_i_to_s_c(k1)), buf1),
-                       l2, (bch2_bkey_val_to_text(&PBUF(buf2), c, bkey_i_to_s_c(k2)), buf2));
+                       l1, buf1.buf,
+                       l2, buf2.buf);
        }
 fsck_err:
+       printbuf_exit(&buf2);
+       printbuf_exit(&buf1);
        return ret;
 }
 
@@ -918,10 +941,10 @@ static struct bch_sb_field_clean *read_superblock_clean(struct bch_fs *c)
                        GFP_KERNEL);
        if (!clean) {
                mutex_unlock(&c->sb_lock);
-               return ERR_PTR(-ENOMEM);
+               return ERR_PTR(-BCH_ERR_ENOMEM_read_superblock_clean);
        }
 
-       ret = bch2_sb_clean_validate(c, clean, READ);
+       ret = bch2_sb_clean_validate_late(c, clean, READ);
        if (ret) {
                mutex_unlock(&c->sb_lock);
                return ERR_PTR(ret);
@@ -935,6 +958,20 @@ fsck_err:
        return ERR_PTR(ret);
 }
 
+static bool btree_id_is_alloc(enum btree_id id)
+{
+       switch (id) {
+       case BTREE_ID_alloc:
+       case BTREE_ID_backpointers:
+       case BTREE_ID_need_discard:
+       case BTREE_ID_freespace:
+       case BTREE_ID_bucket_gens:
+               return true;
+       default:
+               return false;
+       }
+}
+
 static int read_btree_roots(struct bch_fs *c)
 {
        unsigned i;
@@ -946,14 +983,14 @@ static int read_btree_roots(struct bch_fs *c)
                if (!r->alive)
                        continue;
 
-               if (i == BTREE_ID_alloc &&
+               if (btree_id_is_alloc(i) &&
                    c->opts.reconstruct_alloc) {
                        c->sb.compat &= ~(1ULL << BCH_COMPAT_alloc_info);
                        continue;
                }
 
                if (r->error) {
-                       __fsck_err(c, i == BTREE_ID_alloc
+                       __fsck_err(c, btree_id_is_alloc(i)
                                   ? FSCK_CAN_IGNORE : 0,
                                   "invalid btree root %s",
                                   bch2_btree_ids[i]);
@@ -963,18 +1000,25 @@ static int read_btree_roots(struct bch_fs *c)
 
                ret = bch2_btree_root_read(c, i, &r->key, r->level);
                if (ret) {
-                       __fsck_err(c, i == BTREE_ID_alloc
+                       __fsck_err(c,
+                                  btree_id_is_alloc(i)
                                   ? FSCK_CAN_IGNORE : 0,
                                   "error reading btree root %s",
                                   bch2_btree_ids[i]);
-                       if (i == BTREE_ID_alloc)
+                       if (btree_id_is_alloc(i))
                                c->sb.compat &= ~(1ULL << BCH_COMPAT_alloc_info);
                }
        }
 
-       for (i = 0; i < BTREE_ID_NR; i++)
-               if (!c->btree_roots[i].b)
+       for (i = 0; i < BTREE_ID_NR; i++) {
+               struct btree_root *r = &c->btree_roots[i];
+
+               if (!r->b) {
+                       r->alive = false;
+                       r->level = 0;
                        bch2_btree_root_alloc(c, i);
+               }
+       }
 fsck_err:
        return ret;
 }
@@ -999,7 +1043,6 @@ static int bch2_fs_initialize_subvolumes(struct bch_fs *c)
        if (ret)
                return ret;
 
-
        bkey_subvolume_init(&root_volume.k_i);
        root_volume.k.p.offset = BCACHEFS_ROOT_SUBVOL;
        root_volume.v.flags     = 0;
@@ -1017,7 +1060,6 @@ static int bch2_fs_initialize_subvolumes(struct bch_fs *c)
 
 static int bch2_fs_upgrade_for_subvolumes(struct btree_trans *trans)
 {
-       struct bch_fs *c = trans->c;
        struct btree_iter iter;
        struct bkey_s_c k;
        struct bch_inode_unpacked inode;
@@ -1031,7 +1073,7 @@ static int bch2_fs_upgrade_for_subvolumes(struct btree_trans *trans)
                goto err;
 
        if (!bkey_is_inode(k.k)) {
-               bch_err(c, "root inode not found");
+               bch_err(trans->c, "root inode not found");
                ret = -ENOENT;
                goto err;
        }
@@ -1052,7 +1094,7 @@ int bch2_fs_recovery(struct bch_fs *c)
        const char *err = "cannot allocate memory";
        struct bch_sb_field_clean *clean = NULL;
        struct jset *last_journal_entry = NULL;
-       u64 blacklist_seq, journal_seq;
+       u64 last_seq, blacklist_seq, journal_seq;
        bool write_sb = false;
        int ret = 0;
 
@@ -1093,28 +1135,21 @@ int bch2_fs_recovery(struct bch_fs *c)
                c->opts.fix_errors = FSCK_OPT_YES;
        }
 
-       if (!c->replicas.entries ||
-           c->opts.rebuild_replicas) {
-               bch_info(c, "building replicas info");
-               set_bit(BCH_FS_REBUILD_REPLICAS, &c->flags);
-       }
-
        if (!c->opts.nochanges) {
-               if (c->sb.version < bcachefs_metadata_version_inode_backpointers) {
-                       bch_info(c, "version prior to inode backpointers, upgrade and fsck required");
+               if (c->sb.version < bcachefs_metadata_version_no_bps_in_alloc_keys) {
+                       bch_info(c, "version prior to no_bps_in_alloc_keys, upgrade and fsck required");
                        c->opts.version_upgrade = true;
                        c->opts.fsck            = true;
                        c->opts.fix_errors      = FSCK_OPT_YES;
-               } else if (c->sb.version < bcachefs_metadata_version_subvol_dirent) {
-                       bch_info(c, "filesystem version is prior to subvol_dirent - upgrading");
-                       c->opts.version_upgrade = true;
-                       c->opts.fsck            = true;
-               } else if (c->sb.version < bcachefs_metadata_version_inode_v2) {
-                       bch_info(c, "filesystem version is prior to inode_v2 - upgrading");
-                       c->opts.version_upgrade = true;
                }
        }
 
+       if (c->opts.fsck && c->opts.norecovery) {
+               bch_err(c, "cannot select both norecovery and fsck");
+               ret = -EINVAL;
+               goto err;
+       }
+
        ret = bch2_blacklist_table_initialize(c);
        if (ret) {
                bch_err(c, "error initializing blacklist table");
@@ -1122,16 +1157,24 @@ int bch2_fs_recovery(struct bch_fs *c)
        }
 
        if (!c->sb.clean || c->opts.fsck || c->opts.keep_journal) {
-               struct journal_replay *i;
+               struct genradix_iter iter;
+               struct journal_replay **i;
 
-               ret = bch2_journal_read(c, &c->journal_entries,
-                                       &blacklist_seq, &journal_seq);
+               bch_verbose(c, "starting journal read");
+               ret = bch2_journal_read(c, &last_seq, &blacklist_seq, &journal_seq);
                if (ret)
                        goto err;
 
-               list_for_each_entry_reverse(i, &c->journal_entries, list)
-                       if (!i->ignore) {
-                               last_journal_entry = &i->j;
+               /*
+                * note: cmd_list_journal needs the blacklist table fully up to date so
+                * it can asterisk ignored journal entries:
+                */
+               if (c->opts.read_journal_only)
+                       goto out;
+
+               genradix_for_each_reverse(&c->journal_entries, iter, i)
+                       if (*i && !(*i)->ignore) {
+                               last_journal_entry = &(*i)->j;
                                break;
                        }
 
@@ -1146,14 +1189,20 @@ int bch2_fs_recovery(struct bch_fs *c)
 
                if (!last_journal_entry) {
                        fsck_err_on(!c->sb.clean, c, "no journal entries found");
-                       goto use_clean;
+                       if (clean)
+                               goto use_clean;
+
+                       genradix_for_each_reverse(&c->journal_entries, iter, i)
+                               if (*i) {
+                                       last_journal_entry = &(*i)->j;
+                                       (*i)->ignore = false;
+                                       break;
+                               }
                }
 
-               c->journal_keys = journal_keys_sort(&c->journal_entries);
-               if (!c->journal_keys.d) {
-                       ret = -ENOMEM;
+               ret = journal_keys_sort(c);
+               if (ret)
                        goto err;
-               }
 
                if (c->sb.clean && last_journal_entry) {
                        ret = verify_superblock_clean(c, &clean,
@@ -1165,7 +1214,7 @@ int bch2_fs_recovery(struct bch_fs *c)
 use_clean:
                if (!clean) {
                        bch_err(c, "no superblock clean section found");
-                       ret = BCH_FSCK_REPAIR_IMPOSSIBLE;
+                       ret = -BCH_ERR_fsck_repair_impossible;
                        goto err;
 
                }
@@ -1179,12 +1228,24 @@ use_clean:
 
        zero_out_btree_mem_ptr(&c->journal_keys);
 
-       ret = journal_replay_early(c, clean, &c->journal_entries);
+       ret = journal_replay_early(c, clean);
        if (ret)
                goto err;
 
+       /*
+        * After an unclean shutdown, skip then next few journal sequence
+        * numbers as they may have been referenced by btree writes that
+        * happened before their corresponding journal writes - those btree
+        * writes need to be ignored, by skipping and blacklisting the next few
+        * journal sequence numbers:
+        */
+       if (!c->sb.clean)
+               journal_seq += 8;
+
        if (blacklist_seq != journal_seq) {
-               ret = bch2_journal_seq_blacklist_add(c,
+               ret =   bch2_journal_log_msg(c, "blacklisting entries %llu-%llu",
+                                            blacklist_seq, journal_seq) ?:
+                       bch2_journal_seq_blacklist_add(c,
                                        blacklist_seq, journal_seq);
                if (ret) {
                        bch_err(c, "error creating new journal seq blacklist entry");
@@ -1192,18 +1253,35 @@ use_clean:
                }
        }
 
-       ret = bch2_fs_journal_start(&c->journal, journal_seq,
-                                   &c->journal_entries);
+       ret =   bch2_journal_log_msg(c, "starting journal at entry %llu, replaying %llu-%llu",
+                                    journal_seq, last_seq, blacklist_seq - 1) ?:
+               bch2_fs_journal_start(&c->journal, journal_seq);
        if (ret)
                goto err;
 
+       if (c->opts.reconstruct_alloc)
+               bch2_journal_log_msg(c, "dropping alloc info");
+
+       /*
+        * Skip past versions that might have possibly been used (as nonces),
+        * but hadn't had their pointers written:
+        */
+       if (c->sb.encryption_type && !c->sb.clean)
+               atomic64_add(1 << 16, &c->key_version);
+
        ret = read_btree_roots(c);
        if (ret)
                goto err;
 
        bch_verbose(c, "starting alloc read");
        err = "error reading allocation information";
-       ret = bch2_alloc_read(c);
+
+       down_read(&c->gc_lock);
+       ret = c->sb.version < bcachefs_metadata_version_bucket_gens
+               ? bch2_alloc_read(c)
+               : bch2_bucket_gens_read(c);
+       up_read(&c->gc_lock);
+
        if (ret)
                goto err;
        bch_verbose(c, "alloc read done");
@@ -1215,76 +1293,124 @@ use_clean:
                goto err;
        bch_verbose(c, "stripes_read done");
 
-       set_bit(BCH_FS_ALLOC_READ_DONE, &c->flags);
+       if (c->sb.version < bcachefs_metadata_version_snapshot_2) {
+               err = "error creating root snapshot node";
+               ret = bch2_fs_initialize_subvolumes(c);
+               if (ret)
+                       goto err;
+       }
+
+       bch_verbose(c, "reading snapshots table");
+       err = "error reading snapshots table";
+       ret = bch2_fs_snapshots_start(c);
+       if (ret)
+               goto err;
+       bch_verbose(c, "reading snapshots done");
 
-       if (c->opts.fsck ||
-           !(c->sb.compat & (1ULL << BCH_COMPAT_alloc_info)) ||
-           !(c->sb.compat & (1ULL << BCH_COMPAT_alloc_metadata)) ||
-           test_bit(BCH_FS_REBUILD_REPLICAS, &c->flags)) {
+       if (c->opts.fsck) {
                bool metadata_only = c->opts.norecovery;
 
-               bch_info(c, "starting mark and sweep");
-               err = "error in mark and sweep";
+               bch_info(c, "checking allocations");
+               err = "error checking allocations";
                ret = bch2_gc(c, true, metadata_only);
                if (ret)
                        goto err;
-               bch_verbose(c, "mark and sweep done");
-       }
+               bch_verbose(c, "done checking allocations");
 
-       bch2_stripes_heap_start(c);
+               set_bit(BCH_FS_INITIAL_GC_DONE, &c->flags);
 
-       clear_bit(BCH_FS_REBUILD_REPLICAS, &c->flags);
-       set_bit(BCH_FS_INITIAL_GC_DONE, &c->flags);
+               set_bit(BCH_FS_MAY_GO_RW, &c->flags);
 
-       /*
-        * Skip past versions that might have possibly been used (as nonces),
-        * but hadn't had their pointers written:
-        */
-       if (c->sb.encryption_type && !c->sb.clean)
-               atomic64_add(1 << 16, &c->key_version);
+               bch_info(c, "starting journal replay, %zu keys", c->journal_keys.nr);
+               err = "journal replay failed";
+               ret = bch2_journal_replay(c, last_seq, blacklist_seq - 1);
+               if (ret)
+                       goto err;
+               if (c->opts.verbose || !c->sb.clean)
+                       bch_info(c, "journal replay done");
 
-       if (c->opts.norecovery)
-               goto out;
+               bch_info(c, "checking need_discard and freespace btrees");
+               err = "error checking need_discard and freespace btrees";
+               ret = bch2_check_alloc_info(c);
+               if (ret)
+                       goto err;
+               bch_verbose(c, "done checking need_discard and freespace btrees");
 
-       bch_verbose(c, "starting journal replay");
-       err = "journal replay failed";
-       ret = bch2_journal_replay(c);
-       if (ret)
-               goto err;
-       bch_verbose(c, "journal replay done");
+               set_bit(BCH_FS_CHECK_ALLOC_DONE, &c->flags);
 
-       if (test_bit(BCH_FS_NEED_ALLOC_WRITE, &c->flags) &&
-           !c->opts.nochanges) {
-               /*
-                * note that even when filesystem was clean there might be work
-                * to do here, if we ran gc (because of fsck) which recalculated
-                * oldest_gen:
-                */
-               bch_verbose(c, "writing allocation info");
-               err = "error writing out alloc info";
-               ret = bch2_alloc_write_all(c, BTREE_INSERT_LAZY_RW);
-               if (ret) {
-                       bch_err(c, "error writing alloc info");
+               bch_info(c, "checking lrus");
+               err = "error checking lrus";
+               ret = bch2_check_lrus(c);
+               if (ret)
                        goto err;
-               }
-               bch_verbose(c, "alloc write done");
-       }
+               bch_verbose(c, "done checking lrus");
+               set_bit(BCH_FS_CHECK_LRUS_DONE, &c->flags);
 
-       if (c->sb.version < bcachefs_metadata_version_snapshot_2) {
-               bch2_fs_lazy_rw(c);
+               bch_info(c, "checking backpointers to alloc keys");
+               err = "error checking backpointers to alloc keys";
+               ret = bch2_check_btree_backpointers(c);
+               if (ret)
+                       goto err;
+               bch_verbose(c, "done checking backpointers to alloc keys");
 
-               err = "error creating root snapshot node";
-               ret = bch2_fs_initialize_subvolumes(c);
+               bch_info(c, "checking backpointers to extents");
+               err = "error checking backpointers to extents";
+               ret = bch2_check_backpointers_to_extents(c);
+               if (ret)
+                       goto err;
+               bch_verbose(c, "done checking backpointers to extents");
+
+               bch_info(c, "checking extents to backpointers");
+               err = "error checking extents to backpointers";
+               ret = bch2_check_extents_to_backpointers(c);
+               if (ret)
+                       goto err;
+               bch_verbose(c, "done checking extents to backpointers");
+               set_bit(BCH_FS_CHECK_BACKPOINTERS_DONE, &c->flags);
+
+               bch_info(c, "checking alloc to lru refs");
+               err = "error checking alloc to lru refs";
+               ret = bch2_check_alloc_to_lru_refs(c);
+               if (ret)
+                       goto err;
+               bch_verbose(c, "done checking alloc to lru refs");
+               set_bit(BCH_FS_CHECK_ALLOC_TO_LRU_REFS_DONE, &c->flags);
+       } else {
+               set_bit(BCH_FS_INITIAL_GC_DONE, &c->flags);
+               set_bit(BCH_FS_CHECK_ALLOC_DONE, &c->flags);
+               set_bit(BCH_FS_CHECK_LRUS_DONE, &c->flags);
+               set_bit(BCH_FS_CHECK_BACKPOINTERS_DONE, &c->flags);
+               set_bit(BCH_FS_CHECK_ALLOC_TO_LRU_REFS_DONE, &c->flags);
+               set_bit(BCH_FS_FSCK_DONE, &c->flags);
+
+               if (c->opts.norecovery)
+                       goto out;
+
+               set_bit(BCH_FS_MAY_GO_RW, &c->flags);
+
+               bch_verbose(c, "starting journal replay, %zu keys", c->journal_keys.nr);
+               err = "journal replay failed";
+               ret = bch2_journal_replay(c, last_seq, blacklist_seq - 1);
                if (ret)
                        goto err;
+               if (c->opts.verbose || !c->sb.clean)
+                       bch_info(c, "journal replay done");
        }
 
-       bch_verbose(c, "reading snapshots table");
-       err = "error reading snapshots table";
-       ret = bch2_fs_snapshots_start(c);
+       err = "error initializing freespace";
+       ret = bch2_fs_freespace_init(c);
        if (ret)
                goto err;
-       bch_verbose(c, "reading snapshots done");
+
+       if (c->sb.version < bcachefs_metadata_version_bucket_gens &&
+           c->opts.version_upgrade) {
+               bch_info(c, "initializing bucket_gens");
+               err = "error initializing bucket gens";
+               ret = bch2_bucket_gens_init(c);
+               if (ret)
+                       goto err;
+               bch_verbose(c, "bucket_gens init done");
+       }
 
        if (c->sb.version < bcachefs_metadata_version_snapshot_2) {
                /* set bi_subvol on root inode */
@@ -1320,14 +1446,6 @@ use_clean:
        }
 
        mutex_lock(&c->sb_lock);
-       /*
-        * With journal replay done, we can clear the journal seq blacklist
-        * table:
-        */
-       BUG_ON(!test_bit(JOURNAL_REPLAY_DONE, &c->journal.flags));
-       if (le16_to_cpu(c->sb.version_min) >= bcachefs_metadata_version_btree_ptr_sectors_written)
-               bch2_sb_resize_journal_seq_blacklist(&c->disk_sb, 0);
-
        if (c->opts.version_upgrade) {
                c->disk_sb.sb->version = cpu_to_le16(bcachefs_metadata_version_current);
                c->disk_sb.sb->features[0] |= cpu_to_le64(BCH_SB_FEATURES_ALL);
@@ -1356,7 +1474,7 @@ use_clean:
            le16_to_cpu(c->sb.version_min) < bcachefs_metadata_version_btree_ptr_sectors_written) {
                struct bch_move_stats stats;
 
-               bch_move_stats_init(&stats, "recovery");
+               bch2_move_stats_init(&stats, "recovery");
 
                bch_info(c, "scanning for old btree nodes");
                ret = bch2_fs_read_write(c);
@@ -1369,20 +1487,31 @@ use_clean:
                bch_info(c, "scanning for old btree nodes done");
        }
 
+       if (c->journal_seq_blacklist_table &&
+           c->journal_seq_blacklist_table->nr > 128)
+               queue_work(system_long_wq, &c->journal_seq_blacklist_gc_work);
+
        ret = 0;
 out:
        set_bit(BCH_FS_FSCK_DONE, &c->flags);
        bch2_flush_fsck_errs(c);
 
-       if (!c->opts.keep_journal) {
+       if (!c->opts.keep_journal &&
+           test_bit(JOURNAL_REPLAY_DONE, &c->journal.flags)) {
                bch2_journal_keys_free(&c->journal_keys);
-               bch2_journal_entries_free(&c->journal_entries);
+               bch2_journal_entries_free(c);
        }
        kfree(clean);
+
+       if (!ret && test_bit(BCH_FS_HAVE_DELETED_SNAPSHOTS, &c->flags)) {
+               bch2_fs_read_write_early(c);
+               bch2_delete_dead_snapshots_async(c);
+       }
+
        if (ret)
-               bch_err(c, "Error in recovery: %s (%i)", err, ret);
+               bch_err(c, "Error in recovery: %s (%s)", err, bch2_err_str(ret));
        else
-               bch_verbose(c, "ret %i", ret);
+               bch_verbose(c, "ret %s", bch2_err_str(ret));
        return ret;
 err:
 fsck_err:
@@ -1397,7 +1526,6 @@ int bch2_fs_initialize(struct bch_fs *c)
        struct qstr lostfound = QSTR("lost+found");
        const char *err = "cannot allocate memory";
        struct bch_dev *ca;
-       LIST_HEAD(journal);
        unsigned i;
        int ret;
 
@@ -1407,6 +1535,9 @@ int bch2_fs_initialize(struct bch_fs *c)
        c->disk_sb.sb->compat[0] |= cpu_to_le64(1ULL << BCH_COMPAT_extents_above_btree_updates_done);
        c->disk_sb.sb->compat[0] |= cpu_to_le64(1ULL << BCH_COMPAT_bformat_overflow_done);
 
+       if (c->sb.version < bcachefs_metadata_version_inode_v3)
+               c->opts.version_upgrade = true;
+
        if (c->opts.version_upgrade) {
                c->disk_sb.sb->version = cpu_to_le16(bcachefs_metadata_version_current);
                c->disk_sb.sb->features[0] |= cpu_to_le64(BCH_SB_FEATURES_ALL);
@@ -1414,15 +1545,18 @@ int bch2_fs_initialize(struct bch_fs *c)
        }
        mutex_unlock(&c->sb_lock);
 
-       set_bit(BCH_FS_ALLOC_READ_DONE, &c->flags);
        set_bit(BCH_FS_INITIAL_GC_DONE, &c->flags);
+       set_bit(BCH_FS_CHECK_LRUS_DONE, &c->flags);
+       set_bit(BCH_FS_CHECK_BACKPOINTERS_DONE, &c->flags);
+       set_bit(BCH_FS_CHECK_ALLOC_TO_LRU_REFS_DONE, &c->flags);
+       set_bit(BCH_FS_MAY_GO_RW, &c->flags);
+       set_bit(BCH_FS_FSCK_DONE, &c->flags);
 
        for (i = 0; i < BTREE_ID_NR; i++)
                bch2_btree_root_alloc(c, i);
 
-       set_bit(BCH_FS_ALLOC_REPLAY_DONE, &c->flags);
-       set_bit(BCH_FS_BTREE_INTERIOR_REPLAY_DONE, &c->flags);
-       set_bit(JOURNAL_RECLAIM_STARTED, &c->journal.flags);
+       for_each_online_member(ca, c, i)
+               bch2_dev_usage_init(ca);
 
        err = "unable to allocate journal buckets";
        for_each_online_member(ca, c, i) {
@@ -1437,7 +1571,7 @@ int bch2_fs_initialize(struct bch_fs *c)
         * journal_res_get() will crash if called before this has
         * set up the journal.pin FIFO and journal.cur pointer:
         */
-       bch2_fs_journal_start(&c->journal, 1, &journal);
+       bch2_fs_journal_start(&c->journal, 1);
        bch2_journal_set_replay_done(&c->journal);
 
        err = "error going read-write";
@@ -1449,6 +1583,7 @@ int bch2_fs_initialize(struct bch_fs *c)
         * Write out the superblock and journal buckets, now that we can do
         * btree updates
         */
+       bch_verbose(c, "marking superblocks");
        err = "error marking superblock and journal";
        for_each_member_device(ca, c, i) {
                ret = bch2_trans_mark_dev_sb(c, ca);
@@ -1460,6 +1595,12 @@ int bch2_fs_initialize(struct bch_fs *c)
                ca->new_fs_bucket_idx = 0;
        }
 
+       bch_verbose(c, "initializing freespace");
+       err = "error initializing freespace";
+       ret = bch2_fs_freespace_init(c);
+       if (ret)
+               goto err;
+
        err = "error creating root snapshot node";
        ret = bch2_fs_initialize_subvolumes(c);
        if (ret)
@@ -1472,11 +1613,10 @@ int bch2_fs_initialize(struct bch_fs *c)
                goto err;
        bch_verbose(c, "reading snapshots done");
 
-       bch2_inode_init(c, &root_inode, 0, 0,
-                       S_IFDIR|S_IRWXU|S_IRUGO|S_IXUGO, 0, NULL);
+       bch2_inode_init(c, &root_inode, 0, 0, S_IFDIR|0755, 0, NULL);
        root_inode.bi_inum      = BCACHEFS_ROOT_INO;
        root_inode.bi_subvol    = BCACHEFS_ROOT_SUBVOL;
-       bch2_inode_pack(c, &packed_inode, &root_inode);
+       bch2_inode_pack(&packed_inode, &root_inode);
        packed_inode.inode.k.p.snapshot = U32_MAX;
 
        err = "error creating root directory";
@@ -1521,6 +1661,6 @@ int bch2_fs_initialize(struct bch_fs *c)
 
        return 0;
 err:
-       pr_err("Error initializing new filesystem: %s (%i)", err, ret);
+       pr_err("Error initializing new filesystem: %s (%s)", err, bch2_err_str(ret));
        return ret;
 }