path: root/fs/bcachefs/chardev.c

// SPDX-License-Identifier: GPL-2.0
#ifndef NO_BCACHEFS_CHARDEV

#include "bcachefs.h"
#include "bcachefs_ioctl.h"
#include "buckets.h"
#include "chardev.h"
#include "disk_accounting.h"
#include "journal.h"
#include "move.h"
#include "recovery_passes.h"
#include "replicas.h"
#include "super.h"
#include "super-io.h"
#include "thread_with_file.h"

#include <linux/cdev.h>
#include <linux/device.h>
#include <linux/fs.h>
#include <linux/ioctl.h>
#include <linux/major.h>
#include <linux/sched/task.h>
#include <linux/slab.h>
#include <linux/uaccess.h>

/* returns with ref on ca->ref */
static struct bch_dev *bch2_device_lookup(struct bch_fs *c, u64 dev,
					  unsigned flags)
{
	struct bch_dev *ca;

	if (flags & BCH_BY_INDEX) {
		if (dev >= c->sb.nr_devices)
			return ERR_PTR(-EINVAL);

		ca = bch2_dev_tryget_noerror(c, dev);
		if (!ca)
			return ERR_PTR(-EINVAL);
	} else {
		char *path;

		path = strndup_user((const char __user *)
				    (unsigned long) dev, PATH_MAX);
		if (IS_ERR(path))
			return ERR_CAST(path);

		ca = bch2_dev_lookup(c, path);
		kfree(path);
	}

	return ca;
}

#if 0
static long bch2_ioctl_assemble(struct bch_ioctl_assemble __user *user_arg)
{
	struct bch_ioctl_assemble arg;
	struct bch_fs *c;
	u64 *user_devs = NULL;
	char **devs = NULL;
	unsigned i;
	int ret = -EFAULT;

	if (copy_from_user(&arg, user_arg, sizeof(arg)))
		return -EFAULT;

	if (arg.flags || arg.pad)
		return -EINVAL;

	user_devs = kmalloc_array(arg.nr_devs, sizeof(u64), GFP_KERNEL);
	if (!user_devs)
		return -ENOMEM;

	devs = kcalloc(arg.nr_devs, sizeof(char *), GFP_KERNEL);

	if (copy_from_user(user_devs, user_arg->devs,
			   sizeof(u64) * arg.nr_devs))
		goto err;

	for (i = 0; i < arg.nr_devs; i++) {
		devs[i] = strndup_user((const char __user *)(unsigned long)
				       user_devs[i],
				       PATH_MAX);
		ret= PTR_ERR_OR_ZERO(devs[i]);
		if (ret)
			goto err;
	}

	c = bch2_fs_open(devs, arg.nr_devs, bch2_opts_empty());
	ret = PTR_ERR_OR_ZERO(c);
	if (!ret)
		closure_put(&c->cl);
err:
	if (devs)
		for (i = 0; i < arg.nr_devs; i++)
			kfree(devs[i]);
	kfree(devs);
	return ret;
}

static long bch2_ioctl_incremental(struct bch_ioctl_incremental __user *user_arg)
{
	struct bch_ioctl_incremental arg;
	const char *err;
	char *path;

	if (copy_from_user(&arg, user_arg, sizeof(arg)))
		return -EFAULT;

	if (arg.flags || arg.pad)
		return -EINVAL;

	path = strndup_user((const char __user *)(unsigned long) arg.dev, PATH_MAX);
	ret = PTR_ERR_OR_ZERO(path);
	if (ret)
		return ret;

	err = bch2_fs_open_incremental(path);
	kfree(path);

	if (err) {
		pr_err("Could not register bcachefs devices: %s", err);
		return -EINVAL;
	}

	return 0;
}
#endif

struct fsck_thread {
	struct thread_with_stdio thr;
	struct bch_fs		*c;
	struct bch_opts		opts;
};

static void bch2_fsck_thread_exit(struct thread_with_stdio *_thr)
{
	struct fsck_thread *thr = container_of(_thr, struct fsck_thread, thr);
	kfree(thr);
}

static int bch2_fsck_offline_thread_fn(struct thread_with_stdio *stdio)
{
	struct fsck_thread *thr = container_of(stdio, struct fsck_thread, thr);
	struct bch_fs *c = thr->c;

	int ret = PTR_ERR_OR_ZERO(c);
	if (ret)
		return ret;

	ret = bch2_fs_start(thr->c);
	if (ret)
		goto err;

	if (test_bit(BCH_FS_errors_fixed, &c->flags)) {
		bch2_stdio_redirect_printf(&stdio->stdio, false, "%s: errors fixed\n", c->name);
		ret |= 1;
	}
	if (test_bit(BCH_FS_error, &c->flags)) {
		bch2_stdio_redirect_printf(&stdio->stdio, false, "%s: still has errors\n", c->name);
		ret |= 4;
	}
err:
	bch2_fs_stop(c);
	return ret;
}

static const struct thread_with_stdio_ops bch2_offline_fsck_ops = {
	.exit		= bch2_fsck_thread_exit,
	.fn		= bch2_fsck_offline_thread_fn,
};

static long bch2_ioctl_fsck_offline(struct bch_ioctl_fsck_offline __user *user_arg)
{
	struct bch_ioctl_fsck_offline arg;
	struct fsck_thread *thr = NULL;
	darray_str(devs) = {};
	long ret = 0;

	if (copy_from_user(&arg, user_arg, sizeof(arg)))
		return -EFAULT;

	if (arg.flags)
		return -EINVAL;

	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

	for (size_t i = 0; i < arg.nr_devs; i++) {
		u64 dev_u64;
		ret = copy_from_user_errcode(&dev_u64, &user_arg->devs[i], sizeof(u64));
		if (ret)
			goto err;

		char *dev_str = strndup_user((char __user *)(unsigned long) dev_u64, PATH_MAX);
		ret = PTR_ERR_OR_ZERO(dev_str);
		if (ret)
			goto err;

		ret = darray_push(&devs, dev_str);
		if (ret) {
			kfree(dev_str);
			goto err;
		}
	}

	thr = kzalloc(sizeof(*thr), GFP_KERNEL);
	if (!thr) {
		ret = -ENOMEM;
		goto err;
	}

	thr->opts = bch2_opts_empty();

	if (arg.opts) {
		char *optstr = strndup_user((char __user *)(unsigned long) arg.opts, 1 << 16);
		ret =   PTR_ERR_OR_ZERO(optstr) ?:
			bch2_parse_mount_opts(NULL, &thr->opts, NULL, optstr);
		if (!IS_ERR(optstr))
			kfree(optstr);

		if (ret)
			goto err;
	}

	opt_set(thr->opts, stdio, (u64)(unsigned long)&thr->thr.stdio);
	opt_set(thr->