Update bcachefs sources to 6ddf061e68 bcachefs: Use a genradix for reading journal entries

15 files changed, 468 insertions, 146 deletions

diff --git a/.bcachefs_revision b/.bcachefs_revision
index dbcc3d91..a7745cdf 100644
--- a/.bcachefs_revision
+++ b/.bcachefs_revision
@@ -1 +1 @@
-d3da360412f7ca4677975683d3999c038b0cacd7
+6ddf061e68560a2bb263b126af7e894a6c1afb5f
diff --git a/Makefile b/Makefile
index 266f98a1..bed43bda 100644
--- a/Makefile
+++ b/Makefile
@@ -189,6 +189,12 @@ update-bcachefs-sources:
 	git add include/linux/list_nulls.h
 	cp $(LINUX_DIR)/include/linux/poison.h include/linux/
 	git add include/linux/poison.h
+	cp $(LINUX_DIR)/include/linux/generic-radix-tree.h include/linux/
+	git add include/linux/generic-radix-tree.h
+	cp $(LINUX_DIR)/lib/generic-radix-tree.c linux/
+	git add linux/generic-radix-tree.c
+	cp $(LINUX_DIR)/include/linux/kmemleak.h include/linux/
+	git add include/linux/kmemleak.h
 	cp $(LINUX_DIR)/scripts/Makefile.compiler ./
 	git add Makefile.compiler
 	$(RM) libbcachefs/*.mod.c
diff --git a/cmd_debug.c b/cmd_debug.c
index 495c0687..37232481 100644
--- a/cmd_debug.c
+++ b/cmd_debug.c
@@ -624,16 +624,20 @@ int cmd_list_journal(int argc, char *argv[])
 	if (IS_ERR(c))
 		die("error opening %s: %s", argv[0], strerror(-PTR_ERR(c)));
 
-	struct journal_replay *p;
+	struct journal_replay *p, **_p;
+	struct genradix_iter iter;
 	struct jset_entry *entry;
 	struct printbuf buf = PRINTBUF;
 
-	list_for_each_entry(p, &c->journal_entries, list) {
+	genradix_for_each(&c->journal_entries, iter, _p) {
+		p = *_p;
+		if (!p)
+			continue;
+
 		bool blacklisted =
 			bch2_journal_seq_is_blacklisted(c,
 					le64_to_cpu(p->j.seq), false);
 
-
 		if (blacklisted)
 			printf("blacklisted ");
 
diff --git a/include/linux/generic-radix-tree.h b/include/linux/generic-radix-tree.h
index f09689da..c74b7376 100644
--- a/include/linux/generic-radix-tree.h
+++ b/include/linux/generic-radix-tree.h
@@ -2,7 +2,7 @@
 #define _LINUX_GENERIC_RADIX_TREE_H
 
 /**
- * DOC: Generic radix trees/sparse arrays:
+ * DOC: Generic radix trees/sparse arrays
  *
  * Very simple and minimalistic, supporting arbitrary size entries up to
  * PAGE_SIZE.
@@ -38,13 +38,15 @@
 
 #include <asm/page.h>
 #include <linux/bug.h>
-#include <linux/kernel.h>
+#include <linux/limits.h>
 #include <linux/log2.h>
+#include <linux/math.h>
+#include <linux/types.h>
 
 struct genradix_root;
 
 struct __genradix {
-	struct genradix_root __rcu	*root;
+	struct genradix_root		*root;
 };
 
 /*
@@ -115,6 +117,11 @@ static inline size_t __idx_to_offset(size_t idx, size_t obj_size)
 
 #define __genradix_cast(_radix)		(typeof((_radix)->type[0]) *)
 #define __genradix_obj_size(_radix)	sizeof((_radix)->type[0])
+#define __genradix_objs_per_page(_radix)			\
+	(PAGE_SIZE / sizeof((_radix)->type[0]))
+#define __genradix_page_remainder(_radix)			\
+	(PAGE_SIZE % sizeof((_radix)->type[0]))
+
 #define __genradix_idx_to_offset(_radix, _idx)			\
 	__idx_to_offset(_idx, __genradix_obj_size(_radix))
 
@@ -178,14 +185,30 @@ void *__genradix_iter_peek(struct genradix_iter *, struct __genradix *, size_t);
 #define genradix_iter_peek(_iter, _radix)			\
 	(__genradix_cast(_radix)				\
 	 __genradix_iter_peek(_iter, &(_radix)->tree,		\
-			      PAGE_SIZE / __genradix_obj_size(_radix)))
+			__genradix_objs_per_page(_radix)))
+
+void *__genradix_iter_peek_prev(struct genradix_iter *, struct __genradix *,
+				size_t, size_t);
+
+/**
+ * genradix_iter_peek - get first entry at or below iterator's current
+ *			position
+ * @_iter:	a genradix_iter
+ * @_radix:	genradix being iterated over
+ *
+ * If no more entries exist at or below @_iter's current position, returns NULL
+ */
+#define genradix_iter_peek_prev(_iter, _radix)			\
+	(__genradix_cast(_radix)				\
+	 __genradix_iter_peek_prev(_iter, &(_radix)->tree,	\
+			__genradix_objs_per_page(_radix),	\
+			__genradix_obj_size(_radix) +		\
+			__genradix_page_remainder(_radix)))
 
 static inline void __genradix_iter_advance(struct genradix_iter *iter,
 					   size_t obj_size)
 {
-	size_t new_offset = iter->offset + obj_size;
-
-	if (new_offset < iter->offset) {
+	if (iter->offset + obj_size < iter->offset) {
 		iter->offset	= SIZE_MAX;
 		iter->pos	= SIZE_MAX;
 		return;
@@ -203,6 +226,25 @@ static inline void __genradix_iter_advance(struct genradix_iter *iter,
 #define genradix_iter_advance(_iter, _radix)			\
 	__genradix_iter_advance(_iter, __genradix_obj_size(_radix))
 
+static inline void __genradix_iter_rewind(struct genradix_iter *iter,
+					  size_t obj_size)
+{
+	if (iter->offset == 0 ||
+	    iter->offset == SIZE_MAX) {
+		iter->offset = SIZE_MAX;
+		return;
+	}
+
+	if ((iter->offset & (PAGE_SIZE - 1)) == 0)
+		iter->offset -= PAGE_SIZE % obj_size;
+
+	iter->offset -= obj_size;
+	iter->pos--;
+}
+
+#define genradix_iter_rewind(_iter, _radix)			\
+	__genradix_iter_rewind(_iter, __genradix_obj_size(_radix))
+
 #define genradix_for_each_from(_radix, _iter, _p, _start)	\
 	for (_iter = genradix_iter_init(_radix, _start);	\
 	     (_p = genradix_iter_peek(&_iter, _radix)) != NULL;	\
@@ -220,6 +262,23 @@ static inline void __genradix_iter_advance(struct genradix_iter *iter,
 #define genradix_for_each(_radix, _iter, _p)			\
 	genradix_for_each_from(_radix, _iter, _p, 0)
 
+#define genradix_last_pos(_radix)				\
+	(SIZE_MAX / PAGE_SIZE * __genradix_objs_per_page(_radix) - 1)
+
+/**
+ * genradix_for_each_reverse - iterate over entry in a genradix, reverse order
+ * @_radix:	genradix to iterate over
+ * @_iter:	a genradix_iter to track current position
+ * @_p:		pointer to genradix entry type
+ *
+ * On every iteration, @_p will point to the current entry, and @_iter.pos
+ * will be the current entry's index.
+ */
+#define genradix_for_each_reverse(_radix, _iter, _p)		\
+	for (_iter = genradix_iter_init(_radix,	genradix_last_pos(_radix));\
+	     (_p = genradix_iter_peek_prev(&_iter, _radix)) != NULL;\
+	     genradix_iter_rewind(&_iter, _radix))
+
 int __genradix_prealloc(struct __genradix *, size_t, gfp_t);
 
 /**
diff --git a/include/linux/kmemleak.h b/include/linux/kmemleak.h
new file mode 100644
index 00000000..34684b20
--- /dev/null
+++ b/include/linux/kmemleak.h
@@ -0,0 +1,125 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * include/linux/kmemleak.h
+ *
+ * Copyright (C) 2008 ARM Limited
+ * Written by Catalin Marinas <catalin.marinas@arm.com>
+ */
+
+#ifndef __KMEMLEAK_H
+#define __KMEMLEAK_H
+
+#include <linux/slab.h>
+#include <linux/vmalloc.h>
+
+#ifdef CONFIG_DEBUG_KMEMLEAK
+
+extern void kmemleak_init(void) __init;
+extern void kmemleak_alloc(const void *ptr, size_t size, int min_count,
+			   gfp_t gfp) __ref;
+extern void kmemleak_alloc_percpu(const void __percpu *ptr, size_t size,
+				  gfp_t gfp) __ref;
+extern void kmemleak_vmalloc(const struct vm_struct *area, size_t size,
+			     gfp_t gfp) __ref;
+extern void kmemleak_free(const void *ptr) __ref;
+extern void kmemleak_free_part(const void *ptr, size_t size) __ref;
+extern void kmemleak_free_percpu(const void __percpu *ptr) __ref;
+extern void kmemleak_update_trace(const void *ptr) __ref;
+extern void kmemleak_not_leak(const void *ptr) __ref;
+extern void kmemleak_ignore(const void *ptr) __ref;
+extern void kmemleak_scan_area(const void *ptr, size_t size, gfp_t gfp) __ref;
+extern void kmemleak_no_scan(const void *ptr) __ref;
+extern void kmemleak_alloc_phys(phys_addr_t phys, size_t size, int min_count,
+				gfp_t gfp) __ref;
+extern void kmemleak_free_part_phys(phys_addr_t phys, size_t size) __ref;
+extern void kmemleak_not_leak_phys(phys_addr_t phys) __ref;
+extern void kmemleak_ignore_phys(phys_addr_t phys) __ref;
+
+static inline void kmemleak_alloc_recursive(const void *ptr, size_t size,
+					    int min_count, slab_flags_t flags,
+					    gfp_t gfp)
+{
+	if (!(flags & SLAB_NOLEAKTRACE))
+		kmemleak_alloc(ptr, size, min_count, gfp);
+}
+
+static inline void kmemleak_free_recursive(const void *ptr, slab_flags_t flags)
+{
+	if (!(flags & SLAB_NOLEAKTRACE))
+		kmemleak_free(ptr);
+}
+
+static inline void kmemleak_erase(void **ptr)
+{
+	*ptr = NULL;
+}
+
+#else
+
+static inline void kmemleak_init(void)
+{
+}
+static inline void kmemleak_alloc(const void *ptr, size_t size, int min_count,
+				  gfp_t gfp)
+{
+}
+static inline void kmemleak_alloc_recursive(const void *ptr, size_t size,
+					    int min_count, slab_flags_t flags,
+					    gfp_t gfp)
+{
+}
+static inline void kmemleak_alloc_percpu(const void __percpu *ptr, size_t size,
+					 gfp_t gfp)
+{
+}
+static inline void kmemleak_vmalloc(const struct vm_struct *area, size_t size,
+				    gfp_t gfp)
+{
+}
+static inline void kmemleak_free(const void *ptr)
+{
+}
+static inline void kmemleak_free_part(const void *ptr, size_t size)
+{
+}
+static inline void kmemleak_free_recursive(const void *ptr, slab_flags_t flags)
+{
+}
+static inline void kmemleak_free_percpu(const void __percpu *ptr)
+{
+}
+static inline void kmemleak_update_trace(const void *ptr)
+{
+}
+static inline void kmemleak_not_leak(const void *ptr)
+{
+}
+static inline void kmemleak_ignore(const void *ptr)
+{
+}
+static inline void kmemleak_scan_area(const void *ptr, size_t size, gfp_t gfp)
+{
+}
+static inline void kmemleak_erase(void **ptr)
+{
+}
+static inline void kmemleak_no_scan(const void *ptr)
+{
+}
+static inline void kmemleak_alloc_phys(phys_addr_t phys, size_t size,
+				       int min_count, gfp_t gfp)
+{
+}
+static inline void kmemleak_free_part_phys(phys_addr_t phys, size_t size)
+{
+}
+static inline void kmemleak_not_leak_phys(phys_addr_t phys)
+{
+}
+static inline void kmemleak_ignore_phys(phys_addr_t phys)
+{
+}
+
+#endif	/* CONFIG_DEBUG_KMEMLEAK */
+
+#endif	/* __KMEMLEAK_H */
diff --git a/include/linux/types.h b/include/linux/types.h
index 7eb2222f..f0efcd2e 100644
--- a/include/linux/types.h
+++ b/include/linux/types.h
@@ -79,4 +79,8 @@ typedef u64 sector_t;
 
 typedef int (*cmp_func_t)(const void *a, const void *b);
 
+typedef unsigned int __bitwise slab_flags_t;
+typedef u64 phys_addr_t;
+struct vm_struct;
+
 #endif /* _TOOLS_LINUX_TYPES_H_ */
diff --git a/libbcachefs/bcachefs.h b/libbcachefs/bcachefs.h
index ab6df637..e29a0891 100644
--- a/libbcachefs/bcachefs.h
+++ b/libbcachefs/bcachefs.h
@@ -894,7 +894,8 @@ struct bch_fs {
 	mempool_t		btree_bounce_pool;
 
 	struct journal		journal;
-	struct list_head	journal_entries;
+	GENRADIX(struct journal_replay *) journal_entries;
+	u64			journal_entries_base_seq;
 	struct journal_keys	journal_keys;
 	struct list_head	journal_iters;
 
diff --git a/libbcachefs/journal.c b/libbcachefs/journal.c
index d01b1cd4..75be0a5f 100644
--- a/libbcachefs/journal.c
+++ b/libbcachefs/journal.c
@@ -1040,17 +1040,25 @@ void bch2_fs_journal_stop(struct journal *j)
 	cancel_delayed_work_sync(&j->write_work);
 }
 
-int bch2_fs_journal_start(struct journal *j, u64 cur_seq,
-			  struct list_head *journal_entries)
+int bch2_fs_journal_start(struct journal *j, u64 cur_seq)
 {
 	struct bch_fs *c = container_of(j, struct bch_fs, journal);
 	struct journal_entry_pin_list *p;
-	struct journal_replay *i;
+	struct journal_replay *i, **_i;
+	struct genradix_iter iter;
+	bool had_entries = false;
+	unsigned ptr;
 	u64 last_seq = cur_seq, nr, seq;
 
-	if (!list_empty(journal_entries))
-		last_seq = le64_to_cpu(list_last_entry(journal_entries,
-				struct journal_replay, list)->j.last_seq);
+	genradix_for_each_reverse(&c->journal_entries, iter, _i) {
+		i = *_i;
+
+		if (!i || i->ignore)
+			continue;
+
+		last_seq = le64_to_cpu(i->j.last_seq);
+		break;
+	}
 
 	nr = cur_seq - last_seq;
 
@@ -1072,14 +1080,14 @@ int bch2_fs_journal_start(struct journal *j, u64 cur_seq,
 	j->pin.back		= cur_seq;
 	atomic64_set(&j->seq, cur_seq - 1);
 
-	if (list_empty(journal_entries))
-		j->last_empty_seq = cur_seq - 1;
-
 	fifo_for_each_entry_ptr(p, &j->pin, seq)
 		journal_pin_list_init(p, 1);
 
-	list_for_each_entry(i, journal_entries, list) {
-		unsigned ptr;
+	genradix_for_each(&c->journal_entries, iter, _i) {
+		i = *_i;
+
+		if (!i || i->ignore)
+			continue;
 
 		seq = le64_to_cpu(i->j.seq);
 		BUG_ON(seq >= cur_seq);
@@ -1095,9 +1103,11 @@ int bch2_fs_journal_start(struct journal *j, u64 cur_seq,
 		p->devs.nr = 0;
 		for (ptr = 0; ptr < i->nr_ptrs; ptr++)
 			bch2_dev_list_add_dev(&p->devs, i->ptrs[ptr].dev);
+
+		had_entries = true;
 	}
 
-	if (list_empty(journal_entries))
+	if (!had_entries)
 		j->last_empty_seq = cur_seq;
 
 	spin_lock(&j->lock);
diff --git a/libbcachefs/journal.h b/libbcachefs/journal.h
index e7321c32..7fee0c05 100644
--- a/libbcachefs/journal.h
+++ b/libbcachefs/journal.h
@@ -512,7 +512,7 @@ int bch2_dev_journal_alloc(struct bch_dev *);
 void bch2_dev_journal_stop(struct journal *, struct bch_dev *);
 
 void bch2_fs_journal_stop(struct journal *);
-int bch2_fs_journal_start(struct journal *, u64, struct list_head *);
+int bch2_fs_journal_start(struct journal *, u64);
 
 void bch2_dev_journal_exit(struct bch_dev *);
 int bch2_dev_journal_init(struct bch_dev *, struct bch_sb *);
diff --git a/libbcachefs/journal_io.c b/libbcachefs/journal_io.c
index 5e08932c..eb20bf05 100644
--- a/libbcachefs/journal_io.c
+++ b/libbcachefs/journal_io.c
@@ -17,12 +17,22 @@
 
 #include <trace/events/bcachefs.h>
 
-static void __journal_replay_free(struct journal_replay *i)
+static inline u32 journal_entry_radix_idx(struct bch_fs *c,
+					  struct jset *j)
 {
-	list_del(&i->list);
+	return (le64_to_cpu(j->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, &i->j));
+
+	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 +40,12 @@ 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;
 	struct mutex		lock;
-	struct list_head	*head;
 	int			ret;
 };
 
@@ -52,19 +61,30 @@ static int journal_entry_add(struct bch_fs *c, struct bch_dev *ca,
 			     struct journal_list *jlist, struct jset *j,
 			     bool bad)
 {
-	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;
 	int ret = JOURNAL_ENTRY_ADD_OK;
 
+	/*
+	 * Xarrays 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);
+
+#if 0
 	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;
 		}
 	}
+#endif
 
 	/* Is this entry older than the range we need? */
 	if (!c->opts.read_entire_journal &&
@@ -75,28 +95,20 @@ static int journal_entry_add(struct bch_fs *c, struct bch_dev *ca,
 
 	/* Drop entries we don't need anymore */
 	if (!JSET_NO_FLUSH(j)) {
-		list_for_each_entry_safe(i, pos, jlist->head, list) {
+		genradix_for_each(&c->journal_entries, iter, _i) {
+			i = *_i;
+
+			if (!i)
+				continue;
+
 			if (le64_to_cpu(i->j.seq) >= le64_to_cpu(j->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;
-
-	if (dup && le64_to_cpu(j->seq) != le64_to_cpu(dup->j.seq))
-		dup = NULL;
+	_i = genradix_ptr(&c->journal_entries, journal_entry_radix_idx(c, j));
+	dup = _i ? *_i : NULL;
 
 	/*
 	 * Duplicate journal entries? If so we want the one that didn't have a
@@ -132,10 +144,19 @@ add:
 	if (dup) {
 		i->nr_ptrs = dup->nr_ptrs;
 		memcpy(i->ptrs, dup->ptrs, sizeof(dup->ptrs));
-		__journal_replay_free(dup);
+		__journal_replay_free(c, dup);
 	}
 
-	list_add(&i->list, where);
+	_i = genradix_ptr_alloc(&c->journal_entries,
+				journal_entry_radix_idx(c, &i->j),
+				GFP_KERNEL);
+	if (!_i) {
+		bch_err(c, "failed to allocate c->journal_entries entry");
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	*_i = i;
 found:
 	for (ptr = i->ptrs; ptr < i->ptrs + i->nr_ptrs; ptr++) {
 		if (ptr->dev == ca->dev_idx) {
@@ -914,7 +935,8 @@ 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;
@@ -957,7 +979,12 @@ static void bch2_journal_read_device(struct closure *cl)
 	ja->sectors_free = ca->mi.bucket_size;
 
 	mutex_lock(&jlist->lock);
-	list_for_each_entry(r, jlist->head, list) {
+	genradix_for_each(&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]) {
@@ -1023,11 +1050,11 @@ 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 *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;
@@ -1038,7 +1065,6 @@ int bch2_journal_read(struct bch_fs *c, struct list_head *list,
 
 	closure_init_stack(&jlist.cl);
 	mutex_init(&jlist.lock);
-	jlist.head = list;
 	jlist.ret = 0;
 
 	for_each_member_device(ca, c, iter) {
@@ -1062,22 +1088,21 @@ 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;
+	*start_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) {
+		i = *_i;
+
+		if (!i || i->ignore)
 			continue;
 
+		if (!*start_seq)
+			*start_seq = le64_to_cpu(i->j.seq) + 1;
+
 		if (!JSET_NO_FLUSH(&i->j)) {
 			last_seq	= le64_to_cpu(i->j.last_seq);
 			*blacklist_seq	= le64_to_cpu(i->j.seq) + 1;
@@ -1087,6 +1112,11 @@ int bch2_journal_read(struct bch_fs *c, struct list_head *list,
 		journal_replay_free(c, i);
 	}
 
+	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;
@@ -1094,8 +1124,10 @@ int bch2_journal_read(struct bch_fs *c, struct list_head *list,
 	}
 
 	/* 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);
@@ -1114,8 +1146,10 @@ int bch2_journal_read(struct bch_fs *c, struct list_head *list,
 
 	/* Check for missing entries: */
 	seq = last_seq;
-	list_for_each_entry(i, list, list) {
-		if (i->ignore)
+	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));
@@ -1137,11 +1171,9 @@ 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);
+				pr_buf(&buf1, " size %zu", vstruct_sectors(&prev->j, c->block_bits));
 			} else
 				pr_buf(&buf1, "(none)");
 			bch2_journal_ptrs_to_text(&buf2, c, i);
@@ -1158,10 +1190,11 @@ int bch2_journal_read(struct bch_fs *c, struct list_head *list,
 			printbuf_exit(&buf2);
 		}
 
+		prev = i;
 		seq++;
 	}
 
-	list_for_each_entry(i, list, list) {
+	genradix_for_each(&c->journal_entries, radix_iter, _i) {
 		struct jset_entry *entry;
 		struct bkey_i *k, *_n;
 		struct bch_replicas_padded replicas = {
@@ -1170,7 +1203,8 @@ int bch2_journal_read(struct bch_fs *c, struct list_head *list,
 		};
 		unsigned ptr;
 
-		if (i->ignore)
+		i = *_i;
+		if (!i || i->ignore)
 			continue;
 
 		ret = jset_validate_entries(c, &i->j, READ);
diff --git a/libbcachefs/journal_io.h b/libbcachefs/journal_io.h
index f2001835..30e995c8 100644
--- a/libbcachefs/journal_io.h
+++ b/libbcachefs/journal_io.h
@@ -7,7 +7,6 @@
  * during cache_registration
  */
 struct journal_replay {
-	struct list_head	list;
 	struct journal_ptr {
 		u8		dev;
 		u32		bucket;
@@ -53,7 +52,7 @@ void bch2_journal_entry_to_text(struct printbuf *, struct bch_fs *,
 void bch2_journal_ptrs_to_text(struct printbuf *, struct bch_fs *,
 			       struct journal_replay *);
 
-int bch2_journal_read(struct bch_fs *, struct list_head *, u64 *, u64 *);
+int bch2_journal_read(struct bch_fs *, u64 *, u64 *);
 
 void bch2_journal_write(struct closure *);
 
diff --git a/libbcachefs/recovery.c b/libbcachefs/recovery.c
index ac75f44d..9aa507c1 100644
--- a/libbcachefs/recovery.c
+++ b/libbcachefs/recovery.c
@@ -198,7 +198,7 @@ int bch2_journal_key_insert_take(struct bch_fs *c, enum btree_id id,
 	if (keys->nr == keys->size) {
 		struct journal_keys new_keys = {
 			.nr			= keys->nr,
-			.size			= keys->size * 2,
+			.size			= max(keys->size, 8UL) * 2,
 			.journal_seq_base	= keys->journal_seq_base,
 		};
 
@@ -433,16 +433,16 @@ void bch2_btree_and_journal_iter_init_node_iter(struct btree_and_journal_iter *i
 
 /* 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);
 }
 
 /*
@@ -474,57 +474,62 @@ void bch2_journal_keys_free(struct journal_keys *keys)
 	keys->nr = keys->gap = keys->size = 0;
 }
 
-static struct journal_keys journal_keys_sort(struct list_head *journal_entries)
+static int journal_keys_sort(struct bch_fs *c)
 {
-	struct journal_replay *i;
+	struct genradix_iter iter;
+	struct journal_replay *i, **_i;
 	struct jset_entry *entry;
 	struct bkey_i *k, *_n;
-	struct journal_keys keys = { NULL };
+	struct journal_keys *keys = &c->journal_keys;
 	struct journal_key *src, *dst;
 	size_t nr_keys = 0;
 
-	if (list_empty(journal_entries))
-		return keys;
+	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;
 
-		if (!keys.journal_seq_base)
-			keys.journal_seq_base = le64_to_cpu(i->j.seq);
+		if (!keys->journal_seq_base)
+			keys->journal_seq_base = le64_to_cpu(i->j.seq);
 
 		for_each_jset_key(k, _n, entry, &i->j)
 			nr_keys++;
 	}
 
-	keys.size = roundup_pow_of_two(nr_keys);
+	if (!nr_keys)
+		return 0;
+
+	keys->size = roundup_pow_of_two(nr_keys);
 
-	keys.d = kvmalloc(sizeof(keys.d[0]) * keys.size, GFP_KERNEL);
-	if (!keys.d)
-		goto err;
+	keys->d = kvmalloc(sizeof(keys->d[0]) * keys->size, GFP_KERNEL);
+	if (!keys->d)
+		return -ENOMEM;
+
+	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);
+		BUG_ON(le64_to_cpu(i->j.seq) - keys->journal_seq_base > U32_MAX);
 
 		for_each_jset_key(k, _n, entry, &i->j)
-			keys.d[keys.nr++] = (struct journal_key) {
+			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,
+					keys->journal_seq_base,
 				.journal_offset	= k->_data - i->j._data,
 			};
 	}
 
-	sort(keys.d, keys.nr, sizeof(keys.d[0]), journal_sort_key_cmp, NULL);
+	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 = 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))
@@ -533,10 +538,9 @@ static struct journal_keys journal_keys_sort(struct list_head *journal_entries)
 		*dst++ = *src++;
 	}
 
-	keys.nr = dst - keys.d;
-	keys.gap = keys.nr;
-err:
-	return keys;
+	keys->nr = dst - keys->d;
+	keys->gap = keys->nr;
+	return 0;
 }
 
 /* journal replay: */
@@ -752,10 +756,8 @@ 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;
 
@@ -768,8 +770,13 @@ 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) {
@@ -1094,17 +1101,17 @@ 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;
 
 		bch_verbose(c, "starting journal read");
-		ret = bch2_journal_read(c, &c->journal_entries,
-					&blacklist_seq, &journal_seq);
+		ret = bch2_journal_read(c, &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;
+		genradix_for_each_reverse(&c->journal_entries, iter, i)
+			if (*i && !(*i)->ignore) {
+				last_journal_entry = &(*i)->j;
 				break;
 			}
 
@@ -1122,11 +1129,9 @@ int bch2_fs_recovery(struct bch_fs *c)
 			goto use_clean;
 		}
 
-		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,
@@ -1155,7 +1160,7 @@ 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;
 
@@ -1178,8 +1183,7 @@ use_clean:
 		}
 	}
 
-	ret = bch2_fs_journal_start(&c->journal, journal_seq,
-				    &c->journal_entries);
+	ret = bch2_fs_journal_start(&c->journal, journal_seq);
 	if (ret)
 		goto err;
 
@@ -1383,7 +1387,7 @@ out:
 
 	if (!c->opts.keep_journal) {
 		bch2_journal_keys_free(&c->journal_keys);
-		bch2_journal_entries_free(&c->journal_entries);
+		bch2_journal_entries_free(c);
 	}
 	kfree(clean);
 	if (ret)
@@ -1404,7 +1408,6 @@ 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;
 
@@ -1444,7 +1447,7 @@ 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";
diff --git a/libbcachefs/recovery.h b/libbcachefs/recovery.h
index 30580a89..ab8b116a 100644
--- a/libbcachefs/recovery.h
+++ b/libbcachefs/recovery.h
@@ -55,7 +55,7 @@ void bch2_btree_and_journal_iter_init_node_iter(struct btree_and_journal_iter *,
 						struct btree *);
 
 void bch2_journal_keys_free(struct journal_keys *);
-void bch2_journal_entries_free(struct list_head *);
+void bch2_journal_entries_free(struct bch_fs *);
 
 int bch2_fs_recovery(struct bch_fs *);
 int bch2_fs_initialize(struct bch_fs *);
diff --git a/libbcachefs/super.c b/libbcachefs/super.c
index aee3206c..e03c03ff 100644
--- a/libbcachefs/super.c
+++ b/libbcachefs/super.c
@@ -450,7 +450,7 @@ static void __bch2_fs_free(struct bch_fs *c)
 	bch2_io_clock_exit(&c->io_clock[READ]);
 	bch2_fs_compress_exit(c);
 	bch2_journal_keys_free(&c->journal_keys);
-	bch2_journal_entries_free(&c->journal_entries);
+	bch2_journal_entries_free(c);
 	percpu_free_rwsem(&c->mark_lock);
 
 	if (c->btree_paths_bufs)
@@ -668,7 +668,6 @@ static struct bch_fs *bch2_fs_alloc(struct bch_sb *sb, struct bch_opts opts)
 	INIT_WORK(&c->journal_seq_blacklist_gc_work,
 		  bch2_blacklist_entries_gc);
 
-	INIT_LIST_HEAD(&c->journal_entries);
 	INIT_LIST_HEAD(&c->journal_iters);
 
 	INIT_LIST_HEAD(&c->fsck_errors);
diff --git a/linux/generic-radix-tree.c b/linux/generic-radix-tree.c
index 7857017c..41f1bcdc 100644
--- a/linux/generic-radix-tree.c
+++ b/linux/generic-radix-tree.c
@@ -3,6 +3,7 @@
 #include <linux/export.h>
 #include <linux/generic-radix-tree.h>
 #include <linux/gfp.h>
+#include <linux/kmemleak.h>
 
 #define GENRADIX_ARY		(PAGE_SIZE / sizeof(struct genradix_node *))
 #define GENRADIX_ARY_SHIFT	ilog2(GENRADIX_ARY)
@@ -37,12 +38,12 @@ static inline size_t genradix_depth_size(unsigned depth)
 #define GENRADIX_DEPTH_MASK				\
 	((unsigned long) (roundup_pow_of_two(GENRADIX_MAX_DEPTH + 1) - 1))
 
-unsigned genradix_root_to_depth(struct genradix_root *r)
+static inline unsigned genradix_root_to_depth(struct genradix_root *r)
 {
 	return (unsigned long) r & GENRADIX_DEPTH_MASK;
 }
 
-struct genradix_node *genradix_root_to_node(struct genradix_root *r)
+static inline struct genradix_node *genradix_root_to_node(struct genradix_root *r)
 {
 	return (void *) ((unsigned long) r & ~GENRADIX_DEPTH_MASK);
 }
@@ -76,6 +77,27 @@ void *__genradix_ptr(struct __genradix *radix, size_t offset)
 }
 EXPORT_SYMBOL(__genradix_ptr);
 
+static inline struct genradix_node *genradix_alloc_node(gfp_t gfp_mask)
+{
+	struct genradix_node *node;
+
+	node = (struct genradix_node *)__get_free_page(gfp_mask|__GFP_ZERO);
+
+	/*
+	 * We're using pages (not slab allocations) directly for kernel data
+	 * structures, so we need to explicitly inform kmemleak of them in order
+	 * to avoid false positive memory leak reports.
+	 */
+	kmemleak_alloc(node, PAGE_SIZE, 1, gfp_mask);
+	return node;
+}
+
+static inline void genradix_free_node(struct genradix_node *node)
+{
+	kmemleak_free(node);
+	free_page((unsigned long)node);
+}
+
 /*
  * Returns pointer to the specified byte @offset within @radix, allocating it if
  * necessary - newly allocated slots are always zeroed out:
@@ -98,8 +120,7 @@ void *__genradix_ptr_alloc(struct __genradix *radix, size_t offset,
 			break;
 
 		if (!new_node) {
-			new_node = (void *)
-				__get_free_page(gfp_mask|__GFP_ZERO);
+			new_node = genradix_alloc_node(gfp_mask);
 			if (!new_node)
 				return NULL;
 		}
@@ -122,8 +143,7 @@ void *__genradix_ptr_alloc(struct __genradix *radix, size_t offset,
 		n = READ_ONCE(*p);
 		if (!n) {
 			if (!new_node) {
-				new_node = (void *)
-					__get_free_page(gfp_mask|__GFP_ZERO);
+				new_node = genradix_alloc_node(gfp_mask);
 				if (!new_node)
 					return NULL;
 			}
@@ -134,7 +154,7 @@ void *__genradix_ptr_alloc(struct __genradix *radix, size_t offset,
 	}
 
 	if (new_node)
-		free_page((unsigned long) new_node);
+		genradix_free_node(new_node);
 
 	return &n->data[offset];
 }
@@ -193,6 +213,64 @@ restart:
 }
 EXPORT_SYMBOL(__genradix_iter_peek);
 
+void *__genradix_iter_peek_prev(struct genradix_iter *iter,
+				struct __genradix *radix,
+				size_t objs_per_page,
+				size_t obj_size_plus_page_remainder)
+{
+	struct genradix_root *r;
+	struct genradix_node *n;
+	unsigned level, i;
+
+	if (iter->offset == SIZE_MAX)
+		return NULL;
+
+restart:
+	r = READ_ONCE(radix->root);
+	if (!r)
+		return NULL;
+
+	n	= genradix_root_to_node(r);
+	level	= genradix_root_to_depth(r);
+
+	if (ilog2(iter->offset) >= genradix_depth_shift(level)) {
+		iter->offset = genradix_depth_size(level);
+		iter->pos = (iter->offset >> PAGE_SHIFT) * objs_per_page;
+
+		iter->offset -= obj_size_plus_page_remainder;
+		iter->pos--;
+	}
+
+	while (level) {
+		level--;
+
+		i = (iter->offset >> genradix_depth_shift(level)) &
+			(GENRADIX_ARY - 1);
+
+		while (!n->children[i]) {
+			size_t objs_per_ptr = genradix_depth_size(level);
+
+			iter->offset = round_down(iter->offset, objs_per_ptr);
+			iter->pos = (iter->offset >> PAGE_SHIFT) * objs_per_page;
+
+			if (!iter->offset)
+				return NULL;
+
+			iter->offset -= obj_size_plus_page_remainder;
+			iter->pos--;
+
+			if (!i)
+				goto restart;
+			--i;
+		}
+
+		n = n->children[i];
+	}
+
+	return &n->data[iter->offset & (PAGE_SIZE - 1)];
+}
+EXPORT_SYMBOL(__genradix_iter_peek_prev);
+
 static void genradix_free_recurse(struct genradix_node *n, unsigned level)
 {
 	if (level) {
@@ -203,7 +281,7 @@ static void genradix_free_recurse(struct genradix_node *n, unsigned level)
 				genradix_free_recurse(n->children[i], level - 1);
 	}
 
-	free_page((unsigned long) n);
+	genradix_free_node(n);
 }
 
 int __genradix_prealloc(struct __genradix *radix, size_t size,