path: root/fs/bcachefs/replicas.c

// SPDX-License-Identifier: GPL-2.0

#include "bcachefs.h"
#include "buckets.h"
#include "disk_accounting.h"
#include "journal.h"
#include "replicas.h"
#include "super-io.h"

#include <linux/sort.h>

static int bch2_cpu_replicas_to_sb_replicas(struct bch_fs *,
					    struct bch_replicas_cpu *);

/* Some (buggy!) compilers don't allow memcmp to be passed as a pointer */
static int bch2_memcmp(const void *l, const void *r,  const void *priv)
{
	size_t size = (size_t) priv;
	return memcmp(l, r, size);
}

/* Replicas tracking - in memory: */

static void verify_replicas_entry(struct bch_replicas_entry_v1 *e)
{
#ifdef CONFIG_BCACHEFS_DEBUG
	BUG_ON(!e->nr_devs);
	BUG_ON(e->nr_required > 1 &&
	       e->nr_required >= e->nr_devs);

	for (unsigned i = 0; i + 1 < e->nr_devs; i++)
		BUG_ON(e->devs[i] >= e->devs[i + 1]);
#endif
}

void bch2_replicas_entry_sort(struct bch_replicas_entry_v1 *e)
{
	bubble_sort(e->devs, e->nr_devs, u8_cmp);
}

static void bch2_cpu_replicas_sort(struct bch_replicas_cpu *r)
{
	eytzinger0_sort_r(r->entries, r->nr, r->entry_size,
			  bch2_memcmp, NULL, (void *)(size_t)r->entry_size);
}

static void bch2_replicas_entry_v0_to_text(struct printbuf *out,
					   struct bch_replicas_entry_v0 *e)
{
	bch2_prt_data_type(out, e->data_type);

	prt_printf(out, ": %u [", e->nr_devs);
	for (unsigned i = 0; i < e->nr_devs; i++)
		prt_printf(out, i ? " %u" : "%u", e->devs[i]);
	prt_printf(out, "]");
}

void bch2_replicas_entry_to_text(struct printbuf *out,
				 struct bch_replicas_entry_v1 *e)
{
	bch2_prt_data_type(out, e->data_type);

	prt_printf(out, ": %u/%u [", e->nr_required, e->nr_devs);
	for (unsigned i = 0; i < e->nr_devs; i++)
		prt_printf(out, i ? " %u" : "%u", e->devs[i]);
	prt_printf(out, "]");
}

static int bch2_replicas_entry_sb_validate(struct bch_replicas_entry_v1 *r,
					   struct bch_sb *sb,
					   struct printbuf *err)
{
	if (!r->nr_devs) {
		prt_printf(err, "no devices in entry ");
		goto bad;
	}

	if (r->nr_required > 1 &&
	    r->nr_required >= r->nr_devs) {
		prt_printf(err, "bad nr_required in entry ");
		goto bad;
	}

	for (unsigned i = 0; i < r->nr_devs; i++)
		if (r->devs[i] != BCH_SB_MEMBER_INVALID &&
		    !bch2_member_exists(sb, r->devs[i])) {
			prt_printf(err, "invalid device %u in entry ", r->devs[i]);
			goto bad;
		}

	return 0;
bad:
	bch2_replicas_entry_to_text(err, r);
	return -BCH_ERR_invalid_replicas_entry;
}

int bch2_replicas_entry_validate(struct bch_replicas_entry_v1 *r,
				 struct bch_fs *c,
				 struct printbuf *err)
{
	if (!r->nr_devs) {
		prt_printf(err, "no devices in entry ");
		goto bad;
	}

	if (r->nr_required > 1 &&
	    r->nr_required >= r->nr_devs) {
		prt_printf(err, "bad nr_required in entry ");
		goto bad;
	}

	for (unsigned i = 0; i < r->nr_devs; i++)
		if (r->devs[i] != BCH_SB_MEMBER_INVALID &&
		    !bch2_dev_exists(c, r->devs[i])) {
			prt_printf(err, "invalid device %u in entry ", r->devs[i]);
			goto bad;
		}

	return 0;
bad:
	bch2_replicas_entry_to_text(err, r);
	return -BCH_ERR_invalid_replicas_entry;
}

void bch2_cpu_replicas_to_text(struct printbuf *out,
			       struct bch_replicas_cpu *r)
{
	struct bch_replicas_entry_v1 *e;
	bool first = true;

	for_each_cpu_replicas_entry(r, e) {
		if (!first)
			prt_printf(out, " ");
		first = false;

		bch2_replicas_entry_to_text(out, e);
	}
}

static void extent_to_replicas(struct bkey_s_c k,
			       struct bch_replicas_entry_v1 *r)
{
	struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
	const union bch_extent_entry *entry;
	struct extent_ptr_decoded p;

	r->nr_required	= 1;

	bkey_for_each_ptr_decode(k.k, ptrs, p, entry) {
		if (p.ptr.cached)
			continue;

		if (!p.has_ec)
			replicas_entry_add_dev(r, p.ptr.dev);
		else
			r->nr_required = 0;
	}
}

static void stripe_to_replicas(struct bkey_s_c k,
			       struct bch_replicas_entry_v1 *r)
{
	struct bkey_s_c_stripe s = bkey_s_c_to_stripe(k);
	const struct bch_extent_ptr *ptr;

	r->nr_required	= s.v->nr_blocks - s.v->nr_redundant;

	for (ptr = s.v->ptrs;
	     ptr < s.v->ptrs + s.v->nr_blocks;
	     ptr++)
		replicas_entry_add_dev(r, ptr->dev);
}

void bch2_bkey_to_replicas(struct bch_replicas_entry_v1 *e,
			   struct bkey_s_c k)
{
	e->nr_devs = 0;

	switch (k.k->type) {
	case KEY_TYPE_btree_ptr:
	case KEY_TYPE_btree_ptr_v2:
		e->data_type = BCH_DATA_btree;
		extent_to_replicas(k, e);
		break;
	case KEY_TYPE_extent:
	case KEY_TYPE_reflink_v:
		e->data_type = BCH_DATA_user;
		extent_to_replicas(k, e);
		break