]> git.sesse.net Git - bcachefs-tools-debian/blobdiff - libbcachefs/journal_io.c
Update bcachefs sources to 717b356d1d bcachefs: Convert journal validation to bkey_in...
[bcachefs-tools-debian] / libbcachefs / journal_io.c
index fca9bc47b889cee09a8faa32588d99e93de5aa77..d141c749e39bc2c5cff0315402b647809fe0c0a2 100644 (file)
 #include "journal_reclaim.h"
 #include "journal_seq_blacklist.h"
 #include "replicas.h"
+#include "sb-clean.h"
+#include "trace.h"
 
-#include <trace/events/bcachefs.h>
+static struct nonce journal_nonce(const struct jset *jset)
+{
+       return (struct nonce) {{
+               [0] = 0,
+               [1] = ((__le32 *) &jset->seq)[0],
+               [2] = ((__le32 *) &jset->seq)[1],
+               [3] = BCH_NONCE_JOURNAL,
+       }};
+}
+
+static bool jset_csum_good(struct bch_fs *c, struct jset *j)
+{
+       return bch2_checksum_type_valid(c, JSET_CSUM_TYPE(j)) &&
+               !bch2_crc_cmp(j->csum,
+                             csum_vstruct(c, JSET_CSUM_TYPE(j), journal_nonce(j), j));
+}
 
-static void __journal_replay_free(struct journal_replay *i)
+static inline u32 journal_entry_radix_idx(struct bch_fs *c, u64 seq)
 {
-       list_del(&i->list);
+       return (seq - c->journal_entries_base_seq) & (~0U >> 1);
+}
+
+static void __journal_replay_free(struct bch_fs *c,
+                                 struct journal_replay *i)
+{
+       struct journal_replay **p =
+               genradix_ptr(&c->journal_entries,
+                            journal_entry_radix_idx(c, le64_to_cpu(i->j.seq)));
+
+       BUG_ON(*p != i);
+       *p = NULL;
        kvpfree(i, offsetof(struct journal_replay, j) +
                vstruct_bytes(&i->j));
-
 }
 
 static void journal_replay_free(struct bch_fs *c, struct journal_replay *i)
@@ -30,13 +57,13 @@ static void journal_replay_free(struct bch_fs *c, struct journal_replay *i)
        i->ignore = true;
 
        if (!c->opts.read_entire_journal)
-               __journal_replay_free(i);
+               __journal_replay_free(c, i);
 }
 
 struct journal_list {
        struct closure          cl;
+       u64                     last_seq;
        struct mutex            lock;
-       struct list_head        *head;
        int                     ret;
 };
 
@@ -49,93 +76,104 @@ struct journal_list {
  */
 static int journal_entry_add(struct bch_fs *c, struct bch_dev *ca,
                             struct journal_ptr entry_ptr,
-                            struct journal_list *jlist, struct jset *j,
-                            bool bad)
+                            struct journal_list *jlist, struct jset *j)
 {
-       struct journal_replay *i, *pos, *dup = NULL;
+       struct genradix_iter iter;
+       struct journal_replay **_i, *i, *dup;
        struct journal_ptr *ptr;
-       struct list_head *where;
        size_t bytes = vstruct_bytes(j);
-       u64 last_seq = 0;
+       u64 last_seq = !JSET_NO_FLUSH(j) ? le64_to_cpu(j->last_seq) : 0;
        int ret = JOURNAL_ENTRY_ADD_OK;
 
-       list_for_each_entry_reverse(i, jlist->head, list) {
-               if (!JSET_NO_FLUSH(&i->j)) {
-                       last_seq = le64_to_cpu(i->j.last_seq);
-                       break;
-               }
-       }
-
        /* Is this entry older than the range we need? */
        if (!c->opts.read_entire_journal &&
-           le64_to_cpu(j->seq) < last_seq) {
-               ret = JOURNAL_ENTRY_ADD_OUT_OF_RANGE;
-               goto out;
-       }
+           le64_to_cpu(j->seq) < jlist->last_seq)
+               return JOURNAL_ENTRY_ADD_OUT_OF_RANGE;
+
+       /*
+        * genradixes are indexed by a ulong, not a u64, so we can't index them
+        * by sequence number directly: Assume instead that they will all fall
+        * within the range of +-2billion of the filrst one we find.
+        */
+       if (!c->journal_entries_base_seq)
+               c->journal_entries_base_seq = max_t(s64, 1, le64_to_cpu(j->seq) - S32_MAX);
 
        /* Drop entries we don't need anymore */
-       if (!JSET_NO_FLUSH(j)) {
-               list_for_each_entry_safe(i, pos, jlist->head, list) {
-                       if (le64_to_cpu(i->j.seq) >= le64_to_cpu(j->last_seq))
+       if (last_seq > jlist->last_seq && !c->opts.read_entire_journal) {
+               genradix_for_each_from(&c->journal_entries, iter, _i,
+                                      journal_entry_radix_idx(c, jlist->last_seq)) {
+                       i = *_i;
+
+                       if (!i || i->ignore)
+                               continue;
+
+                       if (le64_to_cpu(i->j.seq) >= last_seq)
                                break;
                        journal_replay_free(c, i);
                }
        }
 
-       list_for_each_entry_reverse(i, jlist->head, list) {
-               if (le64_to_cpu(j->seq) > le64_to_cpu(i->j.seq)) {
-                       where = &i->list;
-                       goto add;
-               }
-       }
-
-       where = jlist->head;
-add:
-       dup = where->next != jlist->head
-               ? container_of(where->next, struct journal_replay, list)
-               : NULL;
+       jlist->last_seq = max(jlist->last_seq, last_seq);
 
-       if (dup && le64_to_cpu(j->seq) != le64_to_cpu(dup->j.seq))
-               dup = NULL;
+       _i = genradix_ptr_alloc(&c->journal_entries,
+                               journal_entry_radix_idx(c, le64_to_cpu(j->seq)),
+                               GFP_KERNEL);
+       if (!_i)
+               return -BCH_ERR_ENOMEM_journal_entry_add;
 
        /*
         * Duplicate journal entries? If so we want the one that didn't have a
         * checksum error:
         */
+       dup = *_i;
        if (dup) {
-               if (dup->bad) {
-                       /* we'll replace @dup: */
-               } else if (bad) {
+               if (bytes == vstruct_bytes(&dup->j) &&
+                   !memcmp(j, &dup->j, bytes)) {
                        i = dup;
                        goto found;
-               } else {
-                       fsck_err_on(bytes != vstruct_bytes(&dup->j) ||
-                                   memcmp(j, &dup->j, bytes), c,
-                                   "found duplicate but non identical journal entries (seq %llu)",
-                                   le64_to_cpu(j->seq));
+               }
+
+               if (!entry_ptr.csum_good) {
                        i = dup;
                        goto found;
                }
-       }
 
-       i = kvpmalloc(offsetof(struct journal_replay, j) + bytes, GFP_KERNEL);
-       if (!i) {
-               ret = -ENOMEM;
-               goto out;
+               if (!dup->csum_good)
+                       goto replace;
+
+               fsck_err(c, "found duplicate but non identical journal entries (seq %llu)",
+                        le64_to_cpu(j->seq));
+               i = dup;
+               goto found;
        }
+replace:
+       i = kvpmalloc(offsetof(struct journal_replay, j) + bytes, GFP_KERNEL);
+       if (!i)
+               return -BCH_ERR_ENOMEM_journal_entry_add;
 
-       i->nr_ptrs       = 0;
-       i->bad          = bad;
+       i->nr_ptrs      = 0;
+       i->csum_good    = entry_ptr.csum_good;
        i->ignore       = false;
-       memcpy(&i->j, j, bytes);
+       unsafe_memcpy(&i->j, j, bytes, "embedded variable length struct");
+       i->ptrs[i->nr_ptrs++] = entry_ptr;
 
        if (dup) {
-               i->nr_ptrs = dup->nr_ptrs;
-               memcpy(i->ptrs, dup->ptrs, sizeof(dup->ptrs));
-               __journal_replay_free(dup);
+               if (dup->nr_ptrs >= ARRAY_SIZE(dup->ptrs)) {
+                       bch_err(c, "found too many copies of journal entry %llu",
+                               le64_to_cpu(i->j.seq));
+                       dup->nr_ptrs = ARRAY_SIZE(dup->ptrs) - 1;
+               }
+
+               /* The first ptr should represent the jset we kept: */
+               memcpy(i->ptrs + i->nr_ptrs,
+                      dup->ptrs,
+                      sizeof(dup->ptrs[0]) * dup->nr_ptrs);
+               i->nr_ptrs += dup->nr_ptrs;
+               __journal_replay_free(c, dup);
        }
 
-       list_add(&i->list, where);
+       *_i = i;
+       return 0;
 found:
        for (ptr = i->ptrs; ptr < i->ptrs + i->nr_ptrs; ptr++) {
                if (ptr->dev == ca->dev_idx) {
@@ -157,16 +195,6 @@ fsck_err:
        return ret;
 }
 
-static struct nonce journal_nonce(const struct jset *jset)
-{
-       return (struct nonce) {{
-               [0] = 0,
-               [1] = ((__le32 *) &jset->seq)[0],
-               [2] = ((__le32 *) &jset->seq)[1],
-               [3] = BCH_NONCE_JOURNAL,
-       }};
-}
-
 /* this fills in a range with empty jset_entries: */
 static void journal_entry_null_range(void *start, void *end)
 {
@@ -180,66 +208,94 @@ static void journal_entry_null_range(void *start, void *end)
 #define JOURNAL_ENTRY_NONE     6
 #define JOURNAL_ENTRY_BAD      7
 
-#define journal_entry_err(c, msg, ...)                                 \
+static void journal_entry_err_msg(struct printbuf *out,
+                                 u32 version,
+                                 struct jset *jset,
+                                 struct jset_entry *entry)
+{
+       prt_str(out, "invalid journal entry, version=");
+       bch2_version_to_text(out, version);
+
+       if (entry) {
+               prt_str(out, " type=");
+               prt_str(out, bch2_jset_entry_types[entry->type]);
+       }
+
+       if (!jset) {
+               prt_printf(out, " in superblock");
+       } else {
+
+               prt_printf(out, " seq=%llu", le64_to_cpu(jset->seq));
+
+               if (entry)
+                       prt_printf(out, " offset=%zi/%u",
+                                  (u64 *) entry - jset->_data,
+                                  le32_to_cpu(jset->u64s));
+       }
+
+       prt_str(out, ": ");
+}
+
+#define journal_entry_err(c, version, jset, entry, msg, ...)           \
 ({                                                                     \
-       switch (write) {                                                \
+       struct printbuf buf = PRINTBUF;                                 \
+                                                                       \
+       journal_entry_err_msg(&buf, version, jset, entry);              \
+       prt_printf(&buf, msg, ##__VA_ARGS__);                           \
+                                                                       \
+       switch (flags & BKEY_INVALID_WRITE) {                           \
        case READ:                                                      \
-               mustfix_fsck_err(c, msg, ##__VA_ARGS__);                \
+               mustfix_fsck_err(c, "%s", buf.buf);                     \
                break;                                                  \
        case WRITE:                                                     \
-               bch_err(c, "corrupt metadata before write:\n"           \
-                       msg, ##__VA_ARGS__);                            \
+               bch_err(c, "corrupt metadata before write: %s\n", buf.buf);\
                if (bch2_fs_inconsistent(c)) {                          \
-                       ret = BCH_FSCK_ERRORS_NOT_FIXED;                \
+                       ret = -BCH_ERR_fsck_errors_not_fixed;           \
                        goto fsck_err;                                  \
                }                                                       \
                break;                                                  \
        }                                                               \
+                                                                       \
+       printbuf_exit(&buf);                                            \
        true;                                                           \
 })
 
-#define journal_entry_err_on(cond, c, msg, ...)                                \
-       ((cond) ? journal_entry_err(c, msg, ##__VA_ARGS__) : false)
+#define journal_entry_err_on(cond, c, version, jset, entry, msg, ...)  \
+       ((cond) ? journal_entry_err(c, version, jset, entry, msg, ##__VA_ARGS__) : false)
 
 #define FSCK_DELETED_KEY       5
 
-static int journal_validate_key(struct bch_fs *c, const char *where,
+static int journal_validate_key(struct bch_fs *c,
+                               struct jset *jset,
                                struct jset_entry *entry,
                                unsigned level, enum btree_id btree_id,
-                               struct bkey_i *k, const char *type,
-                               unsigned version, int big_endian, int write)
+                               struct bkey_i *k,
+                               unsigned version, int big_endian,
+                               enum bkey_invalid_flags flags)
 {
+       int write = flags & BKEY_INVALID_WRITE;
        void *next = vstruct_next(entry);
-       const char *invalid;
+       struct printbuf buf = PRINTBUF;
        int ret = 0;
 
-       if (journal_entry_err_on(!k->k.u64s, c,
-                       "invalid %s in %s entry offset %zi/%u: k->u64s 0",
-                       type, where,
-                       (u64 *) k - entry->_data,
-                       le16_to_cpu(entry->u64s))) {
+       if (journal_entry_err_on(!k->k.u64s, c, version, jset, entry, "k->u64s 0")) {
                entry->u64s = cpu_to_le16((u64 *) k - entry->_data);
                journal_entry_null_range(vstruct_next(entry), next);
                return FSCK_DELETED_KEY;
        }
 
        if (journal_entry_err_on((void *) bkey_next(k) >
-                               (void *) vstruct_next(entry), c,
-                       "invalid %s in %s entry offset %zi/%u: extends past end of journal entry",
-                       type, where,
-                       (u64 *) k - entry->_data,
-                       le16_to_cpu(entry->u64s))) {
+                                (void *) vstruct_next(entry),
+                                c, version, jset, entry,
+                                "extends past end of journal entry")) {
                entry->u64s = cpu_to_le16((u64 *) k - entry->_data);
                journal_entry_null_range(vstruct_next(entry), next);
                return FSCK_DELETED_KEY;
        }
 
-       if (journal_entry_err_on(k->k.format != KEY_FORMAT_CURRENT, c,
-                       "invalid %s in %s entry offset %zi/%u: bad format %u",
-                       type, where,
-                       (u64 *) k - entry->_data,
-                       le16_to_cpu(entry->u64s),
-                       k->k.format)) {
+       if (journal_entry_err_on(k->k.format != KEY_FORMAT_CURRENT,
+                                c, version, jset, entry,
+                                "bad format %u", k->k.format)) {
                le16_add_cpu(&entry->u64s, -((u16) k->k.u64s));
                memmove(k, bkey_next(k), next - (void *) bkey_next(k));
                journal_entry_null_range(vstruct_next(entry), next);
@@ -250,22 +306,26 @@ static int journal_validate_key(struct bch_fs *c, const char *where,
                bch2_bkey_compat(level, btree_id, version, big_endian,
                                 write, NULL, bkey_to_packed(k));
 
-       invalid = bch2_bkey_invalid(c, bkey_i_to_s_c(k),
-                                   __btree_node_type(level, btree_id));
-       if (invalid) {
-               struct printbuf buf = PRINTBUF;
+       if (bch2_bkey_invalid(c, bkey_i_to_s_c(k),
+                             __btree_node_type(level, btree_id), write, &buf)) {
+               printbuf_reset(&buf);
+               journal_entry_err_msg(&buf, version, jset, entry);
+               prt_newline(&buf);
+               printbuf_indent_add(&buf, 2);
 
                bch2_bkey_val_to_text(&buf, c, bkey_i_to_s_c(k));
-               mustfix_fsck_err(c, "invalid %s in %s entry offset %zi/%u: %s\n%s",
-                                type, where,
-                                (u64 *) k - entry->_data,
-                                le16_to_cpu(entry->u64s),
-                                invalid, buf.buf);
-               printbuf_exit(&buf);
+               prt_newline(&buf);
+               bch2_bkey_invalid(c, bkey_i_to_s_c(k),
+                                 __btree_node_type(level, btree_id), write, &buf);
+
+               mustfix_fsck_err(c, "%s", buf.buf);
+               BUG();
 
                le16_add_cpu(&entry->u64s, -((u16) k->k.u64s));
                memmove(k, bkey_next(k), next - (void *) bkey_next(k));
                journal_entry_null_range(vstruct_next(entry), next);
+
+               printbuf_exit(&buf);
                return FSCK_DELETED_KEY;
        }
 
@@ -273,21 +333,24 @@ static int journal_validate_key(struct bch_fs *c, const char *where,
                bch2_bkey_compat(level, btree_id, version, big_endian,
                                 write, NULL, bkey_to_packed(k));
 fsck_err:
+       printbuf_exit(&buf);
        return ret;
 }
 
 static int journal_entry_btree_keys_validate(struct bch_fs *c,
-                                            const char *where,
-                                            struct jset_entry *entry,
-                                            unsigned version, int big_endian, int write)
+                               struct jset *jset,
+                               struct jset_entry *entry,
+                               unsigned version, int big_endian,
+                               enum bkey_invalid_flags flags)
 {
        struct bkey_i *k = entry->start;
 
        while (k != vstruct_last(entry)) {
-               int ret = journal_validate_key(c, where, entry,
+               int ret = journal_validate_key(c, jset, entry,
                                               entry->level,
                                               entry->btree_id,
-                                              k, "key", version, big_endian, write);
+                                              k, version, big_endian,
+                                              flags|BKEY_INVALID_JOURNAL);
                if (ret == FSCK_DELETED_KEY)
                        continue;
 
@@ -303,27 +366,29 @@ static void journal_entry_btree_keys_to_text(struct printbuf *out, struct bch_fs
        struct bkey_i *k;
        bool first = true;
 
-       vstruct_for_each(entry, k) {
+       jset_entry_for_each_key(entry, k) {
                if (!first) {
-                       pr_newline(out);
-                       pr_buf(out, "%s: ", bch2_jset_entry_types[entry->type]);
+                       prt_newline(out);
+                       prt_printf(out, "%s: ", bch2_jset_entry_types[entry->type]);
                }
-               pr_buf(out, "btree=%s l=%u ", bch2_btree_ids[entry->btree_id], entry->level);
+               prt_printf(out, "btree=%s l=%u ", bch2_btree_ids[entry->btree_id], entry->level);
                bch2_bkey_val_to_text(out, c, bkey_i_to_s_c(k));
                first = false;
        }
 }
 
 static int journal_entry_btree_root_validate(struct bch_fs *c,
-                                            const char *where,
-                                            struct jset_entry *entry,
-                                            unsigned version, int big_endian, int write)
+                               struct jset *jset,
+                               struct jset_entry *entry,
+                               unsigned version, int big_endian,
+                               enum bkey_invalid_flags flags)
 {
        struct bkey_i *k = entry->start;
        int ret = 0;
 
        if (journal_entry_err_on(!entry->u64s ||
-                                le16_to_cpu(entry->u64s) != k->k.u64s, c,
+                                le16_to_cpu(entry->u64s) != k->k.u64s,
+                                c, version, jset, entry,
                                 "invalid btree root journal entry: wrong number of keys")) {
                void *next = vstruct_next(entry);
                /*
@@ -336,8 +401,8 @@ static int journal_entry_btree_root_validate(struct bch_fs *c,
                return 0;
        }
 
-       return journal_validate_key(c, where, entry, 1, entry->btree_id, k,
-                                   "btree root", version, big_endian, write);
+       return journal_validate_key(c, jset, entry, 1, entry->btree_id, k,
+                                   version, big_endian, flags);
 fsck_err:
        return ret;
 }
@@ -349,9 +414,10 @@ static void journal_entry_btree_root_to_text(struct printbuf *out, struct bch_fs
 }
 
 static int journal_entry_prio_ptrs_validate(struct bch_fs *c,
-                                           const char *where,
-                                           struct jset_entry *entry,
-                                           unsigned version, int big_endian, int write)
+                               struct jset *jset,
+                               struct jset_entry *entry,
+                               unsigned version, int big_endian,
+                               enum bkey_invalid_flags flags)
 {
        /* obsolete, don't care: */
        return 0;
@@ -363,13 +429,15 @@ static void journal_entry_prio_ptrs_to_text(struct printbuf *out, struct bch_fs
 }
 
 static int journal_entry_blacklist_validate(struct bch_fs *c,
-                                           const char *where,
-                                           struct jset_entry *entry,
-                                           unsigned version, int big_endian, int write)
+                               struct jset *jset,
+                               struct jset_entry *entry,
+                               unsigned version, int big_endian,
+                               enum bkey_invalid_flags flags)
 {
        int ret = 0;
 
-       if (journal_entry_err_on(le16_to_cpu(entry->u64s) != 1, c,
+       if (journal_entry_err_on(le16_to_cpu(entry->u64s) != 1,
+                                c, version, jset, entry,
                "invalid journal seq blacklist entry: bad size")) {
                journal_entry_null_range(entry, vstruct_next(entry));
        }
@@ -383,18 +451,20 @@ static void journal_entry_blacklist_to_text(struct printbuf *out, struct bch_fs
        struct jset_entry_blacklist *bl =
                container_of(entry, struct jset_entry_blacklist, entry);
 
-       pr_buf(out, "seq=%llu", le64_to_cpu(bl->seq));
+       prt_printf(out, "seq=%llu", le64_to_cpu(bl->seq));
 }
 
 static int journal_entry_blacklist_v2_validate(struct bch_fs *c,
-                                              const char *where,
-                                              struct jset_entry *entry,
-                                              unsigned version, int big_endian, int write)
+                               struct jset *jset,
+                               struct jset_entry *entry,
+                               unsigned version, int big_endian,
+                               enum bkey_invalid_flags flags)
 {
        struct jset_entry_blacklist_v2 *bl_entry;
        int ret = 0;
 
-       if (journal_entry_err_on(le16_to_cpu(entry->u64s) != 2, c,
+       if (journal_entry_err_on(le16_to_cpu(entry->u64s) != 2,
+                                c, version, jset, entry,
                "invalid journal seq blacklist entry: bad size")) {
                journal_entry_null_range(entry, vstruct_next(entry));
                goto out;
@@ -403,7 +473,8 @@ static int journal_entry_blacklist_v2_validate(struct bch_fs *c,
        bl_entry = container_of(entry, struct jset_entry_blacklist_v2, entry);
 
        if (journal_entry_err_on(le64_to_cpu(bl_entry->start) >
-                                le64_to_cpu(bl_entry->end), c,
+                                le64_to_cpu(bl_entry->end),
+                                c, version, jset, entry,
                "invalid journal seq blacklist entry: start > end")) {
                journal_entry_null_range(entry, vstruct_next(entry));
        }
@@ -418,15 +489,16 @@ static void journal_entry_blacklist_v2_to_text(struct printbuf *out, struct bch_
        struct jset_entry_blacklist_v2 *bl =
                container_of(entry, struct jset_entry_blacklist_v2, entry);
 
-       pr_buf(out, "start=%llu end=%llu",
+       prt_printf(out, "start=%llu end=%llu",
               le64_to_cpu(bl->start),
               le64_to_cpu(bl->end));
 }
 
 static int journal_entry_usage_validate(struct bch_fs *c,
-                                       const char *where,
-                                       struct jset_entry *entry,
-                                       unsigned version, int big_endian, int write)
+                               struct jset *jset,
+                               struct jset_entry *entry,
+                               unsigned version, int big_endian,
+                               enum bkey_invalid_flags flags)
 {
        struct jset_entry_usage *u =
                container_of(entry, struct jset_entry_usage, entry);
@@ -434,7 +506,7 @@ static int journal_entry_usage_validate(struct bch_fs *c,
        int ret = 0;
 
        if (journal_entry_err_on(bytes < sizeof(*u),
-                                c,
+                                c, version, jset, entry,
                                 "invalid journal entry usage: bad size")) {
                journal_entry_null_range(entry, vstruct_next(entry));
                return ret;
@@ -450,15 +522,16 @@ static void journal_entry_usage_to_text(struct printbuf *out, struct bch_fs *c,
        struct jset_entry_usage *u =
                container_of(entry, struct jset_entry_usage, entry);
 
-       pr_buf(out, "type=%s v=%llu",
+       prt_printf(out, "type=%s v=%llu",
               bch2_fs_usage_types[u->entry.btree_id],
               le64_to_cpu(u->v));
 }
 
 static int journal_entry_data_usage_validate(struct bch_fs *c,
-                                       const char *where,
-                                       struct jset_entry *entry,
-                                       unsigned version, int big_endian, int write)
+                               struct jset *jset,
+                               struct jset_entry *entry,
+                               unsigned version, int big_endian,
+                               enum bkey_invalid_flags flags)
 {
        struct jset_entry_data_usage *u =
                container_of(entry, struct jset_entry_data_usage, entry);
@@ -467,7 +540,7 @@ static int journal_entry_data_usage_validate(struct bch_fs *c,
 
        if (journal_entry_err_on(bytes < sizeof(*u) ||
                                 bytes < sizeof(*u) + u->r.nr_devs,
-                                c,
+                                c, version, jset, entry,
                                 "invalid journal entry usage: bad size")) {
                journal_entry_null_range(entry, vstruct_next(entry));
                return ret;
@@ -484,13 +557,14 @@ static void journal_entry_data_usage_to_text(struct printbuf *out, struct bch_fs
                container_of(entry, struct jset_entry_data_usage, entry);
 
        bch2_replicas_entry_to_text(out, &u->r);
-       pr_buf(out, "=%llu", le64_to_cpu(u->v));
+       prt_printf(out, "=%llu", le64_to_cpu(u->v));
 }
 
 static int journal_entry_clock_validate(struct bch_fs *c,
-                                       const char *where,
-                                       struct jset_entry *entry,
-                                       unsigned version, int big_endian, int write)
+                               struct jset *jset,
+                               struct jset_entry *entry,
+                               unsigned version, int big_endian,
+                               enum bkey_invalid_flags flags)
 {
        struct jset_entry_clock *clock =
                container_of(entry, struct jset_entry_clock, entry);
@@ -498,13 +572,13 @@ static int journal_entry_clock_validate(struct bch_fs *c,
        int ret = 0;
 
        if (journal_entry_err_on(bytes != sizeof(*clock),
-                                c, "invalid journal entry clock: bad size")) {
+                                c, version, jset, entry, "bad size")) {
                journal_entry_null_range(entry, vstruct_next(entry));
                return ret;
        }
 
        if (journal_entry_err_on(clock->rw > 1,
-                                c, "invalid journal entry clock: bad rw")) {
+                                c, version, jset, entry, "bad rw")) {
                journal_entry_null_range(entry, vstruct_next(entry));
                return ret;
        }
@@ -519,13 +593,14 @@ static void journal_entry_clock_to_text(struct printbuf *out, struct bch_fs *c,
        struct jset_entry_clock *clock =
                container_of(entry, struct jset_entry_clock, entry);
 
-       pr_buf(out, "%s=%llu", clock->rw ? "write" : "read", le64_to_cpu(clock->time));
+       prt_printf(out, "%s=%llu", clock->rw ? "write" : "read", le64_to_cpu(clock->time));
 }
 
 static int journal_entry_dev_usage_validate(struct bch_fs *c,
-                                           const char *where,
-                                           struct jset_entry *entry,
-                                           unsigned version, int big_endian, int write)
+                               struct jset *jset,
+                               struct jset_entry *entry,
+                               unsigned version, int big_endian,
+                               enum bkey_invalid_flags flags)
 {
        struct jset_entry_dev_usage *u =
                container_of(entry, struct jset_entry_dev_usage, entry);
@@ -535,7 +610,7 @@ static int journal_entry_dev_usage_validate(struct bch_fs *c,
        int ret = 0;
 
        if (journal_entry_err_on(bytes < expected,
-                                c, "invalid journal entry dev usage: bad size (%u < %u)",
+                                c, version, jset, entry, "bad size (%u < %u)",
                                 bytes, expected)) {
                journal_entry_null_range(entry, vstruct_next(entry));
                return ret;
@@ -544,13 +619,13 @@ static int journal_entry_dev_usage_validate(struct bch_fs *c,
        dev = le32_to_cpu(u->dev);
 
        if (journal_entry_err_on(!bch2_dev_exists2(c, dev),
-                                c, "invalid journal entry dev usage: bad dev")) {
+                                c, version, jset, entry, "bad dev")) {
                journal_entry_null_range(entry, vstruct_next(entry));
                return ret;
        }
 
        if (journal_entry_err_on(u->pad,
-                                c, "invalid journal entry dev usage: bad pad")) {
+                                c, version, jset, entry, "bad pad")) {
                journal_entry_null_range(entry, vstruct_next(entry));
                return ret;
        }
@@ -566,28 +641,27 @@ static void journal_entry_dev_usage_to_text(struct printbuf *out, struct bch_fs
                container_of(entry, struct jset_entry_dev_usage, entry);
        unsigned i, nr_types = jset_entry_dev_usage_nr_types(u);
 
-       pr_buf(out, "dev=%u", le32_to_cpu(u->dev));
+       prt_printf(out, "dev=%u", le32_to_cpu(u->dev));
 
        for (i = 0; i < nr_types; i++) {
                if (i < BCH_DATA_NR)
-                       pr_buf(out, " %s", bch2_data_types[i]);
+                       prt_printf(out, " %s", bch2_data_types[i]);
                else
-                       pr_buf(out, " (unknown data type %u)", i);
-               pr_buf(out, ": buckets=%llu sectors=%llu fragmented=%llu",
+                       prt_printf(out, " (unknown data type %u)", i);
+               prt_printf(out, ": buckets=%llu sectors=%llu fragmented=%llu",
                       le64_to_cpu(u->d[i].buckets),
                       le64_to_cpu(u->d[i].sectors),
                       le64_to_cpu(u->d[i].fragmented));
        }
 
-       pr_buf(out, " buckets_ec: %llu buckets_unavailable: %llu",
-              le64_to_cpu(u->buckets_ec),
-              le64_to_cpu(u->buckets_unavailable));
+       prt_printf(out, " buckets_ec: %llu", le64_to_cpu(u->buckets_ec));
 }
 
 static int journal_entry_log_validate(struct bch_fs *c,
-                                     const char *where,
-                                     struct jset_entry *entry,
-                                     unsigned version, int big_endian, int write)
+                               struct jset *jset,
+                               struct jset_entry *entry,
+                               unsigned version, int big_endian,
+                               enum bkey_invalid_flags flags)
 {
        return 0;
 }
@@ -598,12 +672,29 @@ static void journal_entry_log_to_text(struct printbuf *out, struct bch_fs *c,
        struct jset_entry_log *l = container_of(entry, struct jset_entry_log, entry);
        unsigned bytes = vstruct_bytes(entry) - offsetof(struct jset_entry_log, d);
 
-       pr_buf(out, "%.*s", bytes, l->d);
+       prt_printf(out, "%.*s", bytes, l->d);
+}
+
+static int journal_entry_overwrite_validate(struct bch_fs *c,
+                               struct jset *jset,
+                               struct jset_entry *entry,
+                               unsigned version, int big_endian,
+                               enum bkey_invalid_flags flags)
+{
+       return journal_entry_btree_keys_validate(c, jset, entry,
+                               version, big_endian, READ);
+}
+
+static void journal_entry_overwrite_to_text(struct printbuf *out, struct bch_fs *c,
+                                           struct jset_entry *entry)
+{
+       journal_entry_btree_keys_to_text(out, c, entry);
 }
 
 struct jset_entry_ops {
-       int (*validate)(struct bch_fs *, const char *,
-                       struct jset_entry *, unsigned, int, int);
+       int (*validate)(struct bch_fs *, struct jset *,
+                       struct jset_entry *, unsigned, int,
+                       enum bkey_invalid_flags);
        void (*to_text)(struct printbuf *, struct bch_fs *, struct jset_entry *);
 };
 
@@ -617,13 +708,15 @@ static const struct jset_entry_ops bch2_jset_entry_ops[] = {
 #undef x
 };
 
-int bch2_journal_entry_validate(struct bch_fs *c, const char *where,
+int bch2_journal_entry_validate(struct bch_fs *c,
+                               struct jset *jset,
                                struct jset_entry *entry,
-                               unsigned version, int big_endian, int write)
+                               unsigned version, int big_endian,
+                               enum bkey_invalid_flags flags)
 {
        return entry->type < BCH_JSET_ENTRY_NR
-               ? bch2_jset_entry_ops[entry->type].validate(c, where, entry,
-                               version, big_endian, write)
+               ? bch2_jset_entry_ops[entry->type].validate(c, jset, entry,
+                               version, big_endian, flags)
                : 0;
 }
 
@@ -631,36 +724,30 @@ void bch2_journal_entry_to_text(struct printbuf *out, struct bch_fs *c,
                                struct jset_entry *entry)
 {
        if (entry->type < BCH_JSET_ENTRY_NR) {
-               pr_buf(out, "%s: ", bch2_jset_entry_types[entry->type]);
+               prt_printf(out, "%s: ", bch2_jset_entry_types[entry->type]);
                bch2_jset_entry_ops[entry->type].to_text(out, c, entry);
        } else {
-               pr_buf(out, "(unknown type %u)", entry->type);
+               prt_printf(out, "(unknown type %u)", entry->type);
        }
 }
 
 static int jset_validate_entries(struct bch_fs *c, struct jset *jset,
-                                int write)
+                                enum bkey_invalid_flags flags)
 {
-       char buf[100];
        struct jset_entry *entry;
+       unsigned version = le32_to_cpu(jset->version);
        int ret = 0;
 
        vstruct_for_each(jset, entry) {
-               scnprintf(buf, sizeof(buf), "jset %llu entry offset %zi/%u",
-                         le64_to_cpu(jset->seq),
-                         (u64 *) entry - jset->_data,
-                         le32_to_cpu(jset->u64s));
-
-               if (journal_entry_err_on(vstruct_next(entry) >
-                                        vstruct_last(jset), c,
+               if (journal_entry_err_on(vstruct_next(entry) > vstruct_last(jset),
+                                        c, version, jset, entry,
                                "journal entry extends past end of jset")) {
                        jset->u64s = cpu_to_le32((u64 *) entry - jset->_data);
                        break;
                }
 
-               ret = bch2_journal_entry_validate(c, buf, entry,
-                                       le32_to_cpu(jset->version),
-                                       JSET_BIG_ENDIAN(jset), write);
+               ret = bch2_journal_entry_validate(c, jset, entry,
+                                       version, JSET_BIG_ENDIAN(jset), flags);
                if (ret)
                        break;
        }
@@ -671,12 +758,8 @@ fsck_err:
 static int jset_validate(struct bch_fs *c,
                         struct bch_dev *ca,
                         struct jset *jset, u64 sector,
-                        unsigned bucket_sectors_left,
-                        unsigned sectors_read,
-                        int write)
+                        enum bkey_invalid_flags flags)
 {
-       size_t bytes = vstruct_bytes(jset);
-       struct bch_csum csum;
        unsigned version;
        int ret = 0;
 
@@ -684,74 +767,80 @@ static int jset_validate(struct bch_fs *c,
                return JOURNAL_ENTRY_NONE;
 
        version = le32_to_cpu(jset->version);
-       if (journal_entry_err_on((version != BCH_JSET_VERSION_OLD &&
-                                 version < bcachefs_metadata_version_min) ||
-                                version >= bcachefs_metadata_version_max, c,
-                       "%s sector %llu seq %llu: unknown journal entry version %u",
+       if (journal_entry_err_on(!bch2_version_compatible(version),
+                       c, version, jset, NULL,
+                       "%s sector %llu seq %llu: incompatible journal entry version %u.%u",
                        ca ? ca->name : c->name,
                        sector, le64_to_cpu(jset->seq),
-                       version)) {
+                       BCH_VERSION_MAJOR(version),
+                       BCH_VERSION_MINOR(version))) {
                /* don't try to continue: */
-               return EINVAL;
+               return -EINVAL;
        }
 
-       if (bytes > (sectors_read << 9) &&
-           sectors_read < bucket_sectors_left)
-               return JOURNAL_ENTRY_REREAD;
-
-       if (journal_entry_err_on(bytes > bucket_sectors_left << 9, c,
-                       "%s sector %llu seq %llu: journal entry too big (%zu bytes)",
-                       ca ? ca->name : c->name,
-                       sector, le64_to_cpu(jset->seq), bytes)) {
-               ret = JOURNAL_ENTRY_BAD;
-               le32_add_cpu(&jset->u64s,
-                            -((bytes - (bucket_sectors_left << 9)) / 8));
-       }
-
-       if (journal_entry_err_on(!bch2_checksum_type_valid(c, JSET_CSUM_TYPE(jset)), c,
+       if (journal_entry_err_on(!bch2_checksum_type_valid(c, JSET_CSUM_TYPE(jset)),
+                                c, version, jset, NULL,
                        "%s sector %llu seq %llu: journal entry with unknown csum type %llu",
                        ca ? ca->name : c->name,
                        sector, le64_to_cpu(jset->seq),
-                       JSET_CSUM_TYPE(jset))) {
-               ret = JOURNAL_ENTRY_BAD;
-               goto csum_done;
-       }
-
-       if (write)
-               goto csum_done;
-
-       csum = csum_vstruct(c, JSET_CSUM_TYPE(jset), journal_nonce(jset), jset);
-       if (journal_entry_err_on(bch2_crc_cmp(csum, jset->csum), c,
-                                "%s sector %llu seq %llu: journal checksum bad",
-                                ca ? ca->name : c->name,
-                                sector, le64_to_cpu(jset->seq)))
+                       JSET_CSUM_TYPE(jset)))
                ret = JOURNAL_ENTRY_BAD;
 
-       ret = bch2_encrypt(c, JSET_CSUM_TYPE(jset), journal_nonce(jset),
-                    jset->encrypted_start,
-                    vstruct_end(jset) - (void *) jset->encrypted_start);
-       bch2_fs_fatal_err_on(ret, c,
-                       "error decrypting journal entry: %i", ret);
-csum_done:
        /* last_seq is ignored when JSET_NO_FLUSH is true */
        if (journal_entry_err_on(!JSET_NO_FLUSH(jset) &&
-                                le64_to_cpu(jset->last_seq) > le64_to_cpu(jset->seq), c,
+                                le64_to_cpu(jset->last_seq) > le64_to_cpu(jset->seq),
+                                c, version, jset, NULL,
                                 "invalid journal entry: last_seq > seq (%llu > %llu)",
                                 le64_to_cpu(jset->last_seq),
                                 le64_to_cpu(jset->seq))) {
                jset->last_seq = jset->seq;
                return JOURNAL_ENTRY_BAD;
        }
+
+       ret = jset_validate_entries(c, jset, flags);
 fsck_err:
        return ret;
 }
 
-static int jset_validate_for_write(struct bch_fs *c, struct jset *jset)
+static int jset_validate_early(struct bch_fs *c,
+                        struct bch_dev *ca,
+                        struct jset *jset, u64 sector,
+                        unsigned bucket_sectors_left,
+                        unsigned sectors_read)
 {
-       unsigned sectors = vstruct_sectors(jset, c->block_bits);
+       size_t bytes = vstruct_bytes(jset);
+       unsigned version;
+       enum bkey_invalid_flags flags = BKEY_INVALID_JOURNAL;
+       int ret = 0;
+
+       if (le64_to_cpu(jset->magic) != jset_magic(c))
+               return JOURNAL_ENTRY_NONE;
+
+       version = le32_to_cpu(jset->version);
+       if (journal_entry_err_on(!bch2_version_compatible(version),
+                        c, version, jset, NULL,
+                       "%s sector %llu seq %llu: unknown journal entry version %u.%u",
+                       ca ? ca->name : c->name,
+                       sector, le64_to_cpu(jset->seq),
+                       BCH_VERSION_MAJOR(version),
+                       BCH_VERSION_MINOR(version))) {
+               /* don't try to continue: */
+               return -EINVAL;
+       }
+
+       if (bytes > (sectors_read << 9) &&
+           sectors_read < bucket_sectors_left)
+               return JOURNAL_ENTRY_REREAD;
 
-       return jset_validate(c, NULL, jset, 0, sectors, sectors, WRITE) ?:
-               jset_validate_entries(c, jset, WRITE);
+       if (journal_entry_err_on(bytes > bucket_sectors_left << 9,
+                        c, version, jset, NULL,
+                       "%s sector %llu seq %llu: journal entry too big (%zu bytes)",
+                       ca ? ca->name : c->name,
+                       sector, le64_to_cpu(jset->seq), bytes))
+               le32_add_cpu(&jset->u64s,
+                            -((bytes - (bucket_sectors_left << 9)) / 8));
+fsck_err:
+       return ret;
 }
 
 struct journal_read_buf {
@@ -766,12 +855,12 @@ static int journal_read_buf_realloc(struct journal_read_buf *b,
 
        /* the bios are sized for this many pages, max: */
        if (new_size > JOURNAL_ENTRY_SIZE_MAX)
-               return -ENOMEM;
+               return -BCH_ERR_ENOMEM_journal_read_buf_realloc;
 
        new_size = roundup_pow_of_two(new_size);
        n = kvpmalloc(new_size, GFP_KERNEL);
        if (!n)
-               return -ENOMEM;
+               return -BCH_ERR_ENOMEM_journal_read_buf_realloc;
 
        kvpfree(b->data, b->size);
        b->data = n;
@@ -790,7 +879,7 @@ static int journal_read_bucket(struct bch_dev *ca,
        unsigned sectors, sectors_read = 0;
        u64 offset = bucket_to_sector(ca, ja->buckets[bucket]),
            end = offset + ca->mi.bucket_size;
-       bool saw_bad = false;
+       bool saw_bad = false, csum_good;
        int ret = 0;
 
        pr_debug("reading %u", bucket);
@@ -798,20 +887,20 @@ static int journal_read_bucket(struct bch_dev *ca,
        while (offset < end) {
                if (!sectors_read) {
                        struct bio *bio;
+                       unsigned nr_bvecs;
 reread:
                        sectors_read = min_t(unsigned,
                                end - offset, buf->size >> 9);
+                       nr_bvecs = buf_pages(buf->data, sectors_read << 9);
+
+                       bio = bio_kmalloc(nr_bvecs, GFP_KERNEL);
+                       bio_init(bio, ca->disk_sb.bdev, bio->bi_inline_vecs, nr_bvecs, REQ_OP_READ);
 
-                       bio = bio_kmalloc(GFP_KERNEL,
-                                         buf_pages(buf->data,
-                                                   sectors_read << 9));
-                       bio_set_dev(bio, ca->disk_sb.bdev);
-                       bio->bi_iter.bi_sector  = offset;
-                       bio_set_op_attrs(bio, REQ_OP_READ, 0);
+                       bio->bi_iter.bi_sector = offset;
                        bch2_bio_map(bio, buf->data, sectors_read << 9);
 
                        ret = submit_bio_wait(bio);
-                       bio_put(bio);
+                       kfree(bio);
 
                        if (bch2_dev_io_err_on(ret, ca,
                                               "journal read error: sector %llu",
@@ -829,11 +918,10 @@ reread:
                        j = buf->data;
                }
 
-               ret = jset_validate(c, ca, j, offset,
-                                   end - offset, sectors_read,
-                                   READ);
+               ret = jset_validate_early(c, ca, j, offset,
+                                   end - offset, sectors_read);
                switch (ret) {
-               case BCH_FSCK_OK:
+               case 0:
                        sectors = vstruct_sectors(j, c->block_bits);
                        break;
                case JOURNAL_ENTRY_REREAD:
@@ -847,17 +935,13 @@ reread:
                case JOURNAL_ENTRY_NONE:
                        if (!saw_bad)
                                return 0;
-                       sectors = block_sectors(c);
-                       goto next_block;
-               case JOURNAL_ENTRY_BAD:
-                       saw_bad = true;
                        /*
                         * On checksum error we don't really trust the size
                         * field of the journal entry we read, so try reading
                         * again at next block boundary:
                         */
                        sectors = block_sectors(c);
-                       break;
+                       goto next_block;
                default:
                        return ret;
                }
@@ -873,14 +957,25 @@ reread:
 
                ja->bucket_seq[bucket] = le64_to_cpu(j->seq);
 
+               csum_good = jset_csum_good(c, j);
+               if (!csum_good)
+                       saw_bad = true;
+
+               ret = bch2_encrypt(c, JSET_CSUM_TYPE(j), journal_nonce(j),
+                            j->encrypted_start,
+                            vstruct_end(j) - (void *) j->encrypted_start);
+               bch2_fs_fatal_err_on(ret, c,
+                               "error decrypting journal entry: %i", ret);
+
                mutex_lock(&jlist->lock);
                ret = journal_entry_add(c, ca, (struct journal_ptr) {
+                                       .csum_good      = csum_good,
                                        .dev            = ca->dev_idx,
                                        .bucket         = bucket,
                                        .bucket_offset  = offset -
                                                bucket_to_sector(ca, ja->buckets[bucket]),
                                        .sector         = offset,
-                                       }, jlist, j, ret != 0);
+                                       }, jlist, j);
                mutex_unlock(&jlist->lock);
 
                switch (ret) {
@@ -909,9 +1004,9 @@ static void bch2_journal_read_device(struct closure *cl)
        struct bch_fs *c = ca->fs;
        struct journal_list *jlist =
                container_of(cl->parent, struct journal_list, cl);
-       struct journal_replay *r;
+       struct journal_replay *r, **_r;
+       struct genradix_iter iter;
        struct journal_read_buf buf = { NULL, 0 };
-       u64 min_seq = U64_MAX;
        unsigned i;
        int ret = 0;
 
@@ -930,44 +1025,39 @@ static void bch2_journal_read_device(struct closure *cl)
                        goto err;
        }
 
-       /* Find the journal bucket with the highest sequence number: */
-       for (i = 0; i < ja->nr; i++) {
-               if (ja->bucket_seq[i] > ja->bucket_seq[ja->cur_idx])
-                       ja->cur_idx = i;
-
-               min_seq = min(ja->bucket_seq[i], min_seq);
-       }
-
-       /*
-        * If there's duplicate journal entries in multiple buckets (which
-        * definitely isn't supposed to happen, but...) - make sure to start
-        * cur_idx at the last of those buckets, so we don't deadlock trying to
-        * allocate
-        */
-       while (ja->bucket_seq[ja->cur_idx] > min_seq &&
-              ja->bucket_seq[ja->cur_idx] ==
-              ja->bucket_seq[(ja->cur_idx + 1) % ja->nr])
-               ja->cur_idx = (ja->cur_idx + 1) % ja->nr;
-
        ja->sectors_free = ca->mi.bucket_size;
 
        mutex_lock(&jlist->lock);
-       list_for_each_entry(r, jlist->head, list) {
+       genradix_for_each_reverse(&c->journal_entries, iter, _r) {
+               r = *_r;
+
+               if (!r)
+                       continue;
+
                for (i = 0; i < r->nr_ptrs; i++) {
-                       if (r->ptrs[i].dev == ca->dev_idx &&
-                           sector_to_bucket(ca, r->ptrs[i].sector) == ja->buckets[ja->cur_idx]) {
-                               unsigned wrote = (r->ptrs[i].sector % ca->mi.bucket_size) +
+                       if (r->ptrs[i].dev == ca->dev_idx) {
+                               unsigned wrote = bucket_remainder(ca, r->ptrs[i].sector) +
                                        vstruct_sectors(&r->j, c->block_bits);
 
-                               ja->sectors_free = min(ja->sectors_free,
-                                                      ca->mi.bucket_size - wrote);
+                               ja->cur_idx = r->ptrs[i].bucket;
+                               ja->sectors_free = ca->mi.bucket_size - wrote;
+                               goto found;
                        }
                }
        }
+found:
        mutex_unlock(&jlist->lock);
 
-       BUG_ON(ja->bucket_seq[ja->cur_idx] &&
-              ja->sectors_free == ca->mi.bucket_size);
+       if (ja->bucket_seq[ja->cur_idx] &&
+           ja->sectors_free == ca->mi.bucket_size) {
+               bch_err(c, "ja->sectors_free == ca->mi.bucket_size");
+               bch_err(c, "cur_idx %u/%u", ja->cur_idx, ja->nr);
+               for (i = 0; i < 3; i++) {
+                       unsigned idx = (ja->cur_idx + ja->nr - 1 + i) % ja->nr;
+                       bch_err(c, "bucket_seq[%u] = %llu", idx, ja->bucket_seq[idx]);
+               }
+               ja->sectors_free = 0;
+       }
 
        /*
         * Set dirty_idx to indicate the entire journal is full and needs to be
@@ -1001,8 +1091,8 @@ void bch2_journal_ptrs_to_text(struct printbuf *out, struct bch_fs *c,
                div64_u64_rem(j->ptrs[i].sector, ca->mi.bucket_size, &offset);
 
                if (i)
-                       pr_buf(out, " ");
-               pr_buf(out, "%u:%u:%u (sector %llu)",
+                       prt_printf(out, " ");
+               prt_printf(out, "%u:%u:%u (sector %llu)",
                       j->ptrs[i].dev,
                       j->ptrs[i].bucket,
                       j->ptrs[i].bucket_offset,
@@ -1010,26 +1100,28 @@ void bch2_journal_ptrs_to_text(struct printbuf *out, struct bch_fs *c,
        }
 }
 
-int bch2_journal_read(struct bch_fs *c, struct list_head *list,
-                     u64 *blacklist_seq, u64 *start_seq)
+int bch2_journal_read(struct bch_fs *c,
+                     u64 *last_seq,
+                     u64 *blacklist_seq,
+                     u64 *start_seq)
 {
        struct journal_list jlist;
-       struct journal_replay *i, *t;
+       struct journal_replay *i, **_i, *prev = NULL;
+       struct genradix_iter radix_iter;
        struct bch_dev *ca;
        unsigned iter;
        struct printbuf buf = PRINTBUF;
-       size_t keys = 0, entries = 0;
-       bool degraded = false;
-       u64 seq, last_seq = 0;
+       bool degraded = false, last_write_torn = false;
+       u64 seq;
        int ret = 0;
 
        closure_init_stack(&jlist.cl);
        mutex_init(&jlist.lock);
-       jlist.head = list;
+       jlist.last_seq = 0;
        jlist.ret = 0;
 
        for_each_member_device(ca, c, iter) {
-               if (!test_bit(BCH_FS_REBUILD_REPLICAS, &c->flags) &&
+               if (!c->opts.fsck &&
                    !(bch2_dev_has_data(c, ca) & (1 << BCH_DATA_journal)))
                        continue;
 
@@ -1049,44 +1141,74 @@ int bch2_journal_read(struct bch_fs *c, struct list_head *list,
        if (jlist.ret)
                return jlist.ret;
 
-       if (list_empty(list)) {
-               bch_info(c, "journal read done, but no entries found");
-               return 0;
-       }
-
-       i = list_last_entry(list, struct journal_replay, list);
-       *start_seq = le64_to_cpu(i->j.seq) + 1;
+       *last_seq       = 0;
+       *start_seq      = 0;
+       *blacklist_seq  = 0;
 
        /*
         * Find most recent flush entry, and ignore newer non flush entries -
         * those entries will be blacklisted:
         */
-       list_for_each_entry_safe_reverse(i, t, list, list) {
-               if (i->ignore)
+       genradix_for_each_reverse(&c->journal_entries, radix_iter, _i) {
+               enum bkey_invalid_flags flags = BKEY_INVALID_JOURNAL;
+
+               i = *_i;
+
+               if (!i || i->ignore)
                        continue;
 
-               if (!JSET_NO_FLUSH(&i->j)) {
-                       last_seq        = le64_to_cpu(i->j.last_seq);
-                       *blacklist_seq  = le64_to_cpu(i->j.seq) + 1;
-                       break;
+               if (!*start_seq)
+                       *blacklist_seq = *start_seq = le64_to_cpu(i->j.seq) + 1;
+
+               if (JSET_NO_FLUSH(&i->j)) {
+                       i->ignore = true;
+                       continue;
+               }
+
+               if (!last_write_torn && !i->csum_good) {
+                       last_write_torn = true;
+                       i->ignore = true;
+                       continue;
                }
 
-               journal_replay_free(c, i);
+               if (journal_entry_err_on(le64_to_cpu(i->j.last_seq) > le64_to_cpu(i->j.seq),
+                                        c, le32_to_cpu(i->j.version), &i->j, NULL,
+                                        "invalid journal entry: last_seq > seq (%llu > %llu)",
+                                        le64_to_cpu(i->j.last_seq),
+                                        le64_to_cpu(i->j.seq)))
+                       i->j.last_seq = i->j.seq;
+
+               *last_seq       = le64_to_cpu(i->j.last_seq);
+               *blacklist_seq  = le64_to_cpu(i->j.seq) + 1;
+               break;
        }
 
-       if (!last_seq) {
+       if (!*start_seq) {
+               bch_info(c, "journal read done, but no entries found");
+               return 0;
+       }
+
+       if (!*last_seq) {
                fsck_err(c, "journal read done, but no entries found after dropping non-flushes");
-               ret = -1;
-               goto err;
+               return 0;
        }
 
+       bch_info(c, "journal read done, replaying entries %llu-%llu",
+                *last_seq, *blacklist_seq - 1);
+
+       if (*start_seq != *blacklist_seq)
+               bch_info(c, "dropped unflushed entries %llu-%llu",
+                        *blacklist_seq, *start_seq - 1);
+
        /* Drop blacklisted entries and entries older than last_seq: */
-       list_for_each_entry_safe(i, t, list, list) {
-               if (i->ignore)
+       genradix_for_each(&c->journal_entries, radix_iter, _i) {
+               i = *_i;
+
+               if (!i || i->ignore)
                        continue;
 
                seq = le64_to_cpu(i->j.seq);
-               if (seq < last_seq) {
+               if (seq < *last_seq) {
                        journal_replay_free(c, i);
                        continue;
                }
@@ -1094,15 +1216,16 @@ int bch2_journal_read(struct bch_fs *c, struct list_head *list,
                if (bch2_journal_seq_is_blacklisted(c, seq, true)) {
                        fsck_err_on(!JSET_NO_FLUSH(&i->j), c,
                                    "found blacklisted journal entry %llu", seq);
-
-                       journal_replay_free(c, i);
+                       i->ignore = true;
                }
        }
 
        /* Check for missing entries: */
-       seq = last_seq;
-       list_for_each_entry(i, list, list) {
-               if (i->ignore)
+       seq = *last_seq;
+       genradix_for_each(&c->journal_entries, radix_iter, _i) {
+               i = *_i;
+
+               if (!i || i->ignore)
                        continue;
 
                BUG_ON(seq > le64_to_cpu(i->j.seq));
@@ -1124,13 +1247,11 @@ int bch2_journal_read(struct bch_fs *c, struct list_head *list,
                               !bch2_journal_seq_is_blacklisted(c, seq, false))
                                seq++;
 
-                       if (i->list.prev != list) {
-                               struct journal_replay *p = list_prev_entry(i, list);
-
-                               bch2_journal_ptrs_to_text(&buf1, c, p);
-                               pr_buf(&buf1, " size %zu", vstruct_sectors(&p->j, c->block_bits));
+                       if (prev) {
+                               bch2_journal_ptrs_to_text(&buf1, c, prev);
+                               prt_printf(&buf1, " size %zu", vstruct_sectors(&prev->j, c->block_bits));
                        } else
-                               pr_buf(&buf1, "(none)");
+                               prt_printf(&buf1, "(none)");
                        bch2_journal_ptrs_to_text(&buf2, c, i);
 
                        missing_end = seq - 1;
@@ -1138,29 +1259,43 @@ int bch2_journal_read(struct bch_fs *c, struct list_head *list,
                                 "  prev at %s\n"
                                 "  next at %s",
                                 missing_start, missing_end,
-                                last_seq, *blacklist_seq - 1,
+                                *last_seq, *blacklist_seq - 1,
                                 buf1.buf, buf2.buf);
 
                        printbuf_exit(&buf1);
                        printbuf_exit(&buf2);
                }
 
+               prev = i;
                seq++;
        }
 
-       list_for_each_entry(i, list, list) {
-               struct jset_entry *entry;
-               struct bkey_i *k, *_n;
+       genradix_for_each(&c->journal_entries, radix_iter, _i) {
                struct bch_replicas_padded replicas = {
                        .e.data_type = BCH_DATA_journal,
                        .e.nr_required = 1,
                };
                unsigned ptr;
 
-               if (i->ignore)
+               i = *_i;
+               if (!i || i->ignore)
                        continue;
 
-               ret = jset_validate_entries(c, &i->j, READ);
+               for (ptr = 0; ptr < i->nr_ptrs; ptr++) {
+                       struct bch_dev *ca = bch_dev_bkey_exists(c, i->ptrs[ptr].dev);
+
+                       if (!i->ptrs[ptr].csum_good)
+                               bch_err_dev_offset(ca, i->ptrs[ptr].sector,
+                                                  "invalid journal checksum, seq %llu%s",
+                                                  le64_to_cpu(i->j.seq),
+                                                  i->csum_good ? " (had good copy on another device)" : "");
+               }
+
+               ret = jset_validate(c,
+                                   bch_dev_bkey_exists(c, i->ptrs[0].dev),
+                                   &i->j,
+                                   i->ptrs[0].sector,
+                                   READ);
                if (ret)
                        goto err;
 
@@ -1178,26 +1313,14 @@ int bch2_journal_read(struct bch_fs *c, struct list_head *list,
                bch2_replicas_entry_to_text(&buf, &replicas.e);
 
                if (!degraded &&
-                   (test_bit(BCH_FS_REBUILD_REPLICAS, &c->flags) ||
-                    fsck_err_on(!bch2_replicas_marked(c, &replicas.e), c,
-                                "superblock not marked as containing replicas %s",
-                                buf.buf))) {
+                   fsck_err_on(!bch2_replicas_marked(c, &replicas.e), c,
+                               "superblock not marked as containing replicas %s",
+                               buf.buf)) {
                        ret = bch2_mark_replicas(c, &replicas.e);
                        if (ret)
                                goto err;
                }
-
-               for_each_jset_key(k, _n, entry, &i->j)
-                       keys++;
-               entries++;
        }
-
-       bch_info(c, "journal read done, %zu keys in %zu entries, seq %llu",
-                keys, entries, *start_seq);
-
-       if (*start_seq != *blacklist_seq)
-               bch_info(c, "dropped unflushed entries %llu-%llu",
-                        *blacklist_seq, *start_seq - 1);
 err:
 fsck_err:
        printbuf_exit(&buf);
@@ -1235,8 +1358,7 @@ static void __journal_write_alloc(struct journal *j,
                if (!ca->mi.durability ||
                    ca->mi.state != BCH_MEMBER_STATE_rw ||
                    !ja->nr ||
-                   bch2_bkey_has_device(bkey_i_to_s_c(&w->key),
-                                        ca->dev_idx) ||
+                   bch2_bkey_has_device_c(bkey_i_to_s_c(&w->key), ca->dev_idx) ||
                    sectors > ja->sectors_free)
                        continue;
 
@@ -1336,7 +1458,7 @@ static void journal_buf_realloc(struct journal *j, struct journal_buf *buf)
        if (buf->buf_size >= new_size)
                return;
 
-       new_buf = kvpmalloc(new_size, GFP_NOIO|__GFP_NOWARN);
+       new_buf = kvpmalloc(new_size, GFP_NOFS|__GFP_NOWARN);
        if (!new_buf)
                return;
 
@@ -1360,7 +1482,6 @@ static void journal_write_done(struct closure *cl)
        struct journal *j = container_of(cl, struct journal, io);
        struct bch_fs *c = container_of(j, struct bch_fs, journal);
        struct journal_buf *w = journal_last_unwritten_buf(j);
-       struct bch_replicas_padded replicas;
        union journal_res_state old, new;
        u64 v, seq;
        int err = 0;
@@ -1372,13 +1493,7 @@ static void journal_write_done(struct closure *cl)
        if (!w->devs_written.nr) {
                bch_err(c, "unable to write journal to sufficient devices");
                err = -EIO;
-       } else {
-               bch2_devlist_to_replicas(&replicas.e, BCH_DATA_journal,
-                                        w->devs_written);
-               if (bch2_mark_replicas(c, &replicas.e))
-                       err = -EIO;
        }
-
        if (err)
                bch2_fatal_error(c);
 
@@ -1395,6 +1510,8 @@ static void journal_write_done(struct closure *cl)
 
                        bch2_do_discards(c);
                        closure_wake_up(&c->freelist_wait);
+
+                       bch2_reset_alloc_cursors(c);
                }
        } else if (!j->err_seq || seq < j->err_seq)
                j->err_seq      = seq;
@@ -1408,7 +1525,8 @@ static void journal_write_done(struct closure *cl)
         * Must come before signaling write completion, for
         * bch2_fs_journal_stop():
         */
-       journal_reclaim_kick(&c->journal);
+       if (j->watermark != BCH_WATERMARK_stripe)
+               journal_reclaim_kick(&c->journal);
 
        /* also must come before signalling write completion: */
        closure_debug_destroy(cl);
@@ -1489,12 +1607,10 @@ static void do_journal_write(struct closure *cl)
                             sectors);
 
                bio = ca->journal.bio;
-               bio_reset(bio);
-               bio_set_dev(bio, ca->disk_sb.bdev);
+               bio_reset(bio, ca->disk_sb.bdev, REQ_OP_WRITE|REQ_SYNC|REQ_META);
                bio->bi_iter.bi_sector  = ptr->offset;
                bio->bi_end_io          = journal_write_endio;
                bio->bi_private         = ca;
-               bio->bi_opf             = REQ_OP_WRITE|REQ_SYNC|REQ_META;
 
                BUG_ON(bio->bi_iter.bi_sector == ca->prev_journal_sector);
                ca->prev_journal_sector = bio->bi_iter.bi_sector;
@@ -1506,7 +1622,7 @@ static void do_journal_write(struct closure *cl)
 
                bch2_bio_map(bio, w->data, sectors << 9);
 
-               trace_journal_write(bio);
+               trace_and_count(c, journal_write, bio);
                closure_bio_submit(bio, cl);
 
                ca->journal.bucket_seq[ca->journal.cur_idx] =
@@ -1517,12 +1633,59 @@ static void do_journal_write(struct closure *cl)
        return;
 }
 
+static void bch2_journal_entries_postprocess(struct bch_fs *c, struct jset *jset)
+{
+       struct jset_entry *i, *next, *prev = NULL;
+
+       /*
+        * Simple compaction, dropping empty jset_entries (from journal
+        * reservations that weren't fully used) and merging jset_entries that
+        * can be.
+        *
+        * If we wanted to be really fancy here, we could sort all the keys in
+        * the jset and drop keys that were overwritten - probably not worth it:
+        */
+       vstruct_for_each_safe(jset, i, next) {
+               unsigned u64s = le16_to_cpu(i->u64s);
+
+               /* Empty entry: */
+               if (!u64s)
+                       continue;
+
+               if (i->type == BCH_JSET_ENTRY_btree_root)
+                       bch2_journal_entry_to_btree_root(c, i);
+
+               /* Can we merge with previous entry? */
+               if (prev &&
+                   i->btree_id == prev->btree_id &&
+                   i->level    == prev->level &&
+                   i->type     == prev->type &&
+                   i->type     == BCH_JSET_ENTRY_btree_keys &&
+                   le16_to_cpu(prev->u64s) + u64s <= U16_MAX) {
+                       memmove_u64s_down(vstruct_next(prev),
+                                         i->_data,
+                                         u64s);
+                       le16_add_cpu(&prev->u64s, u64s);
+                       continue;
+               }
+
+               /* Couldn't merge, move i into new position (after prev): */
+               prev = prev ? vstruct_next(prev) : jset->start;
+               if (i != prev)
+                       memmove_u64s_down(prev, i, jset_u64s(u64s));
+       }
+
+       prev = prev ? vstruct_next(prev) : jset->start;
+       jset->u64s = cpu_to_le32((u64 *) prev - jset->_data);
+}
+
 void bch2_journal_write(struct closure *cl)
 {
        struct journal *j = container_of(cl, struct journal, io);
        struct bch_fs *c = container_of(j, struct bch_fs, journal);
        struct bch_dev *ca;
        struct journal_buf *w = journal_last_unwritten_buf(j);
+       struct bch_replicas_padded replicas;
        struct jset_entry *start, *end;
        struct jset *jset;
        struct bio *bio;
@@ -1539,20 +1702,42 @@ void bch2_journal_write(struct closure *cl)
        j->write_start_time = local_clock();
 
        spin_lock(&j->lock);
-       if (bch2_journal_error(j) ||
-           w->noflush ||
-           (!w->must_flush &&
-            (jiffies - j->last_flush_write) < msecs_to_jiffies(c->opts.journal_flush_delay) &&
-            test_bit(JOURNAL_MAY_SKIP_FLUSH, &j->flags))) {
+
+       /*
+        * If the journal is in an error state - we did an emergency shutdown -
+        * we prefer to continue doing journal writes. We just mark them as
+        * noflush so they'll never be used, but they'll still be visible by the
+        * list_journal tool - this helps in debugging.
+        *
+        * There's a caveat: the first journal write after marking the
+        * superblock dirty must always be a flush write, because on startup
+        * from a clean shutdown we didn't necessarily read the journal and the
+        * new journal write might overwrite whatever was in the journal
+        * previously - we can't leave the journal without any flush writes in
+        * it.
+        *
+        * So if we're in an error state, and we're still starting up, we don't
+        * write anything at all.
+        */
+       if (!test_bit(JOURNAL_NEED_FLUSH_WRITE, &j->flags) &&
+           (bch2_journal_error(j) ||
+            w->noflush ||
+            (!w->must_flush &&
+             (jiffies - j->last_flush_write) < msecs_to_jiffies(c->opts.journal_flush_delay) &&
+             test_bit(JOURNAL_MAY_SKIP_FLUSH, &j->flags)))) {
                w->noflush = true;
                SET_JSET_NO_FLUSH(jset, true);
                jset->last_seq  = 0;
                w->last_seq     = 0;
 
                j->nr_noflush_writes++;
-       } else {
+       } else if (!bch2_journal_error(j)) {
                j->last_flush_write = jiffies;
                j->nr_flush_writes++;
+               clear_bit(JOURNAL_NEED_FLUSH_WRITE, &j->flags);
+       } else {
+               spin_unlock(&j->lock);
+               goto err;
        }
        spin_unlock(&j->lock);
 
@@ -1566,7 +1751,7 @@ void bch2_journal_write(struct closure *cl)
         * entry:
         */
 
-       bch2_journal_entries_to_btree_roots(c, jset);
+       bch2_journal_entries_postprocess(c, jset);
 
        start = end = vstruct_last(jset);
 
@@ -1578,12 +1763,19 @@ void bch2_journal_write(struct closure *cl)
        BUG_ON(u64s > j->entry_u64s_reserved);
 
        le32_add_cpu(&jset->u64s, u64s);
-       BUG_ON(vstruct_sectors(jset, c->block_bits) > w->sectors);
+
+       sectors = vstruct_sectors(jset, c->block_bits);
+       bytes   = vstruct_bytes(jset);
+
+       if (sectors > w->sectors) {
+               bch2_fs_fatal_error(c, "aieeee! journal write overran available space, %zu > %u (extra %u reserved %u/%u)",
+                                   vstruct_bytes(jset), w->sectors << 9,
+                                   u64s, w->u64s_reserved, j->entry_u64s_reserved);
+               goto err;
+       }
 
        jset->magic             = cpu_to_le64(jset_magic(c));
-       jset->version           = c->sb.version < bcachefs_metadata_version_bkey_renumber
-               ? cpu_to_le32(BCH_JSET_VERSION_OLD)
-               : cpu_to_le32(c->sb.version);
+       jset->version           = cpu_to_le32(c->sb.version);
 
        SET_JSET_BIG_ENDIAN(jset, CPU_BIG_ENDIAN);
        SET_JSET_CSUM_TYPE(jset, bch2_meta_checksum_type(c));
@@ -1598,7 +1790,7 @@ void bch2_journal_write(struct closure *cl)
                validate_before_checksum = true;
 
        if (validate_before_checksum &&
-           jset_validate_for_write(c, jset))
+           jset_validate(c, NULL, jset, 0, WRITE))
                goto err;
 
        ret = bch2_encrypt(c, JSET_CSUM_TYPE(jset), journal_nonce(jset),
@@ -1612,13 +1804,9 @@ void bch2_journal_write(struct closure *cl)
                                  journal_nonce(jset), jset);
 
        if (!validate_before_checksum &&
-           jset_validate_for_write(c, jset))
+           jset_validate(c, NULL, jset, 0, WRITE))
                goto err;
 
-       sectors = vstruct_sectors(jset, c->block_bits);
-       BUG_ON(sectors > w->sectors);
-
-       bytes = vstruct_bytes(jset);
        memset((void *) jset + bytes, 0, (sectors << 9) - bytes);
 
 retry_alloc:
@@ -1651,9 +1839,7 @@ retry_alloc:
                bch_err(c, "Unable to allocate journal write:\n%s",
                        journal_debug_buf.buf);
                printbuf_exit(&journal_debug_buf);
-               bch2_fatal_error(c);
-               continue_at(cl, journal_write_done, c->io_complete_wq);
-               return;
+               goto err;
        }
 
        w->devs_written = bch2_bkey_devs(bkey_i_to_s_c(&w->key));
@@ -1667,14 +1853,22 @@ retry_alloc:
        if (nr_rw_members > 1)
                w->separate_flush = true;
 
+       /*
+        * Mark journal replicas before we submit the write to guarantee
+        * recovery will find the journal entries after a crash.
+        */
+       bch2_devlist_to_replicas(&replicas.e, BCH_DATA_journal,
+                                w->devs_written);
+       ret = bch2_mark_replicas(c, &replicas.e);
+       if (ret)
+               goto err;
+
        if (!JSET_NO_FLUSH(jset) && w->separate_flush) {
                for_each_rw_member(ca, c, i) {
                        percpu_ref_get(&ca->io_ref);
 
                        bio = ca->journal.bio;
-                       bio_reset(bio);
-                       bio_set_dev(bio, ca->disk_sb.bdev);
-                       bio->bi_opf             = REQ_OP_FLUSH;
+                       bio_reset(bio, ca->disk_sb.bdev, REQ_OP_FLUSH);
                        bio->bi_end_io          = journal_write_endio;
                        bio->bi_private         = ca;
                        closure_bio_submit(bio, cl);