bcachefs: Initial commit

Initially forked from drivers/md/bcache, bcachefs is a new copy-on-write
filesystem with every feature you could possibly want.

Website: https://bcachefs.org

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

1 files changed, 425 insertions, 0 deletions

diff --git a/fs/bcachefs/debug.c b/fs/bcachefs/debug.c
new file mode 100644
index 000000000000..7db0e65927c6
--- /dev/null
+++ b/fs/bcachefs/debug.c
@@ -0,0 +1,425 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Assorted bcachefs debug code
+ *
+ * Copyright 2010, 2011 Kent Overstreet <kent.overstreet@gmail.com>
+ * Copyright 2012 Google, Inc.
+ */
+
+#include "bcachefs.h"
+#include "bkey_methods.h"
+#include "btree_cache.h"
+#include "btree_io.h"
+#include "btree_iter.h"
+#include "btree_update.h"
+#include "buckets.h"
+#include "debug.h"
+#include "error.h"
+#include "extents.h"
+#include "fsck.h"
+#include "inode.h"
+#include "io.h"
+#include "super.h"
+
+#include <linux/console.h>
+#include <linux/debugfs.h>
+#include <linux/module.h>
+#include <linux/random.h>
+#include <linux/seq_file.h>
+
+static struct dentry *bch_debug;
+
+#ifdef CONFIG_BCACHEFS_DEBUG
+
+void __bch2_btree_verify(struct bch_fs *c, struct btree *b)
+{
+	struct btree *v = c->verify_data;
+	struct btree_node *n_ondisk, *n_sorted, *n_inmemory;
+	struct bset *sorted, *inmemory;
+	struct extent_pick_ptr pick;
+	struct bch_dev *ca;
+	struct bio *bio;
+
+	if (c->opts.nochanges)
+		return;
+
+	btree_node_io_lock(b);
+	mutex_lock(&c->verify_lock);
+
+	n_ondisk = c->verify_ondisk;
+	n_sorted = c->verify_data->data;
+	n_inmemory = b->data;
+
+	bkey_copy(&v->key, &b->key);
+	v->written	= 0;
+	v->level	= b->level;
+	v->btree_id	= b->btree_id;
+	bch2_btree_keys_init(v, &c->expensive_debug_checks);
+
+	if (bch2_btree_pick_ptr(c, b, NULL, &pick) <= 0)
+		return;
+
+	ca = bch_dev_bkey_exists(c, pick.ptr.dev);
+	if (!bch2_dev_get_ioref(ca, READ))
+		return;
+
+	bio = bio_alloc_bioset(ca->disk_sb.bdev,
+			       buf_pages(n_sorted, btree_bytes(c)),
+			       REQ_OP_READ|REQ_META,
+			       GFP_NOIO,
+			       &c->btree_bio);
+	bio->bi_iter.bi_sector	= pick.ptr.offset;
+	bio->bi_iter.bi_size	= btree_bytes(c);
+	bch2_bio_map(bio, n_sorted);
+
+	submit_bio_wait(bio);
+
+	bio_put(bio);
+	percpu_ref_put(&ca->io_ref);
+
+	memcpy(n_ondisk, n_sorted, btree_bytes(c));
+
+	if (bch2_btree_node_read_done(c, v, false))
+		goto out;
+
+	n_sorted = c->verify_data->data;
+	sorted = &n_sorted->keys;
+	inmemory = &n_inmemory->keys;
+
+	if (inmemory->u64s != sorted->u64s ||
+	    memcmp(inmemory->start,
+		   sorted->start,
+		   vstruct_end(inmemory) - (void *) inmemory->start)) {
+		unsigned offset = 0, sectors;
+		struct bset *i;
+		unsigned j;
+
+		console_lock();
+
+		printk(KERN_ERR "*** in memory:\n");
+		bch2_dump_bset(b, inmemory, 0);
+
+		printk(KERN_ERR "*** read back in:\n");
+		bch2_dump_bset(v, sorted, 0);
+
+		while (offset < b->written) {
+			if (!offset ) {
+				i = &n_ondisk->keys;
+				sectors = vstruct_blocks(n_ondisk, c->block_bits) <<
+					c->block_bits;
+			} else {
+				struct btree_node_entry *bne =
+					(void *) n_ondisk + (offset << 9);
+				i = &bne->keys;
+
+				sectors = vstruct_blocks(bne, c->block_bits) <<
+					c->block_bits;
+			}
+
+			printk(KERN_ERR "*** on disk block %u:\n", offset);
+			bch2_dump_bset(b, i, offset);
+
+			offset += sectors;
+		}
+
+		printk(KERN_ERR "*** block %u/%u not written\n",
+		       offset >> c->block_bits, btree_blocks(c));
+
+		for (j = 0; j < le16_to_cpu(inmemory->u64s); j++)
+			if (inmemory->_data[j] != sorted->_data[j])
+				break;
+
+		printk(KERN_ERR "b->written %u\n", b->written);
+
+		console_unlock();
+		panic("verify failed at %u\n", j);
+	}
+out:
+	mutex_unlock(&c->verify_lock);
+	btree_node_io_unlock(b);
+}
+
+#endif
+
+#ifdef CONFIG_DEBUG_FS
+
+/* XXX: bch_fs refcounting */
+
+struct dump_iter {
+	struct bpos		from;
+	struct bch_fs	*c;
+	enum btree_id		id;
+
+	char			buf[PAGE_SIZE];
+	size_t			bytes;	/* what's currently in buf */
+
+	char __user		*ubuf;	/* destination user buffer */
+	size_t			size;	/* size of requested read */
+	ssize_t			ret;	/* bytes read so far */
+};
+
+static int flush_buf(struct dump_iter *i)
+{
+	if (i->bytes) {
+		size_t bytes = min(i->bytes, i->size);
+		int err = copy_to_user(i->ubuf, i->buf, bytes);
+
+		if (err)
+			return err;
+
+		i->ret	 += bytes;
+		i->ubuf	 += bytes;
+		i->size	 -= bytes;
+		i->bytes -= bytes;
+		memmove(i->buf, i->buf + bytes, i->bytes);
+	}
+
+	return 0;
+}
+
+static int bch2_dump_open(struct inode *inode, struct file *file)
+{
+	struct btree_debug *bd = inode->i_private;
+	struct dump_iter *i;
+
+	i = kzalloc(sizeof(struct dump_iter), GFP_KERNEL);
+	if (!i)
+		return -ENOMEM;
+
+	file->private_data = i;
+	i->from = POS_MIN;
+	i->c	= container_of(bd, struct bch_fs, btree_debug[bd->id]);
+	i->id	= bd->id;
+
+	return 0;
+}
+
+static int bch2_dump_release(struct inode *inode, struct file *file)
+{
+	kfree(file->private_data);
+	return 0;
+}
+
+static ssize_t bch2_read_btree(struct file *file, char __user *buf,
+			       size_t size, loff_t *ppos)
+{
+	struct dump_iter *i = file->private_data;
+	struct btree_iter iter;
+	struct bkey_s_c k;
+	int err;
+
+	i->ubuf = buf;
+	i->size	= size;
+	i->ret	= 0;
+
+	err = flush_buf(i);
+	if (err)
+		return err;
+
+	if (!i->size)
+		return i->ret;
+
+	bch2_btree_iter_init(&iter, i->c, i->id, i->from, BTREE_ITER_PREFETCH);
+	k = bch2_btree_iter_peek(&iter);
+
+	while (k.k && !(err = btree_iter_err(k))) {
+		bch2_bkey_val_to_text(i->c, bkey_type(0, i->id),
+				      i->buf, sizeof(i->buf), k);
+		i->bytes = strlen(i->buf);
+		BUG_ON(i->bytes >= PAGE_SIZE);
+		i->buf[i->bytes] = '\n';
+		i->bytes++;
+
+		k = bch2_btree_iter_next(&iter);
+		i->from = iter.pos;
+
+		err = flush_buf(i);
+		if (err)
+			break;
+
+		if (!i->size)
+			break;
+	}
+	bch2_btree_iter_unlock(&iter);
+
+	return err < 0 ? err : i->ret;
+}
+
+static const struct file_operations btree_debug_ops = {
+	.owner		= THIS_MODULE,
+	.open		= bch2_dump_open,
+	.release	= bch2_dump_release,
+	.read		= bch2_read_btree,
+};
+
+static ssize_t bch2_read_btree_formats(struct file *file, char __user *buf,
+				       size_t size, loff_t *ppos)
+{
+	struct dump_iter *i = file->private_data;
+	struct btree_iter iter;
+	struct btree *b;
+	int err;
+
+	i->ubuf = buf;
+	i->size	= size;
+	i->ret	= 0;
+
+	err = flush_buf(i);
+	if (err)
+		return err;
+
+	if (!i->size || !bkey_cmp(POS_MAX, i->from))
+		return i->ret;
+
+	for_each_btree_node(&iter, i->c, i->id, i->from, 0, b) {
+		i->bytes = bch2_print_btree_node(i->c, b, i->buf,
+						sizeof(i->buf));
+		err = flush_buf(i);
+		if (err)
+			break;
+
+		/*
+		 * can't easily correctly restart a btree node traversal across
+		 * all nodes, meh
+		 */
+		i->from = bkey_cmp(POS_MAX, b->key.k.p)
+			? bkey_successor(b->key.k.p)
+			: b->key.k.p;
+
+		if (!i->size)
+			break;
+	}
+	bch2_btree_iter_unlock(&iter);
+
+	return err < 0 ? err : i->ret;
+}
+
+static const struct file_operations btree_format_debug_ops = {
+	.owner		= THIS_MODULE,
+	.open		= bch2_dump_open,
+	.release	= bch2_dump_release,
+	.read		= bch2_read_btree_formats,
+};
+
+static ssize_t bch2_read_bfloat_failed(struct file *file, char __user *buf,
+				       size_t size, loff_t *ppos)
+{
+	struct dump_iter *i = file->private_data;
+	struct btree_iter iter;
+	struct bkey_s_c k;
+	struct btree *prev_node = NULL;
+	int err;
+
+	i->ubuf = buf;
+	i->size	= size;
+	i->ret	= 0;
+
+	err = flush_buf(i);
+	if (err)
+		return err;
+
+	if (!i->size)
+		return i->ret;
+
+	bch2_btree_iter_init(&iter, i->c, i->id, i->from, BTREE_ITER_PREFETCH);
+
+	while ((k = bch2_btree_iter_peek(&iter)).k &&
+	       !(err = btree_iter_err(k))) {
+		struct btree_iter_level *l = &iter.l[0];
+		struct bkey_packed *_k =
+			bch2_btree_node_iter_peek(&l->iter, l->b);
+
+		if (l->b != prev_node) {
+			i->bytes = bch2_print_btree_node(i->c, l->b, i->buf,
+							sizeof(i->buf));
+			err = flush_buf(i);
+			if (err)
+				break;
+		}
+		prev_node = l->b;
+
+		i->bytes = bch2_bkey_print_bfloat(l->b, _k, i->buf,
+						  sizeof(i->buf));
+
+		err = flush_buf(i);
+		if (err)
+			break;
+
+		bch2_btree_iter_next(&iter);
+		i->from = iter.pos;
+
+		err = flush_buf(i);
+		if (err)
+			break;
+
+		if (!i->size)
+			break;
+	}
+	bch2_btree_iter_unlock(&iter);
+
+	return err < 0 ? err : i->ret;
+}
+
+static const struct file_operations bfloat_failed_debug_ops = {
+	.owner		= THIS_MODULE,
+	.open		= bch2_dump_open,
+	.release	= bch2_dump_release,
+	.read		= bch2_read_bfloat_failed,
+};
+
+void bch2_fs_debug_exit(struct bch_fs *c)
+{
+	if (!IS_ERR_OR_NULL(c->debug))
+		debugfs_remove_recursive(c->debug);
+}
+
+void bch2_fs_debug_init(struct bch_fs *c)
+{
+	struct btree_debug *bd;
+	char name[100];
+
+	if (IS_ERR_OR_NULL(bch_debug))
+		return;
+
+	snprintf(name, sizeof(name), "%pU", c->sb.user_uuid.b);
+	c->debug = debugfs_create_dir(name, bch_debug);
+	if (IS_ERR_OR_NULL(c->debug))
+		return;
+
+	for (bd = c->btree_debug;
+	     bd < c->btree_debug + ARRAY_SIZE(c->btree_debug);
+	     bd++) {
+		bd->id = bd - c->btree_debug;
+		bd->btree = debugfs_create_file(bch2_btree_ids[bd->id],
+						0400, c->debug, bd,
+						&btree_debug_ops);
+
+		snprintf(name, sizeof(name), "%s-formats",
+			 bch2_btree_ids[bd->id]);
+
+		bd->btree_format = debugfs_create_file(name, 0400, c->debug, bd,
+						       &btree_format_debug_ops);
+
+		snprintf(name, sizeof(name), "%s-bfloat-failed",
+			 bch2_btree_ids[bd->id]);
+
+		bd->failed = debugfs_create_file(name, 0400, c->debug, bd,
+						 &bfloat_failed_debug_ops);
+	}
+}
+
+#endif
+
+void bch2_debug_exit(void)
+{
+	if (!IS_ERR_OR_NULL(bch_debug))
+		debugfs_remove_recursive(bch_debug);
+}
+
+int __init bch2_debug_init(void)
+{
+	int ret = 0;
+
+	bch_debug = debugfs_create_dir("bcachefs", NULL);
+	return ret;
+}