1 files changed, 407 insertions, 0 deletions
diff --git a/libbcachefs/chardev.c b/libbcachefs/chardev.c
new file mode 100644
index 00000000..24b92a29
--- /dev/null
+++ b/libbcachefs/chardev.c
@@ -0,0 +1,407 @@
+#include "bcachefs.h"
+#include "bcachefs_ioctl.h"
+#include "super.h"
+#include "super-io.h"
+
+#include <linux/module.h>
+#include <linux/fs.h>
+#include <linux/major.h>
+#include <linux/cdev.h>
+#include <linux/device.h>
+#include <linux/ioctl.h>
+#include <linux/uaccess.h>
+#include <linux/slab.h>
+
+static long bch2_ioctl_assemble(struct bch_ioctl_assemble __user *user_arg)
+{
+	struct bch_ioctl_assemble arg;
+	const char *err;
+	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 (!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);
+		if (!devs[i]) {
+			ret = -ENOMEM;
+			goto err;
+		}
+	}
+
+	err = bch2_fs_open(devs, arg.nr_devs, bch2_opts_empty(), NULL);
+	if (err) {
+		pr_err("Could not open filesystem: %s", err);
+		ret = -EINVAL;
+		goto err;
+	}
+
+	ret = 0;
+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);
+	if (!path)
+		return -ENOMEM;
+
+	err = bch2_fs_open_incremental(path);
+	kfree(path);
+
+	if (err) {
+		pr_err("Could not register bcachefs devices: %s", err);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static long bch2_global_ioctl(unsigned cmd, void __user *arg)
+{
+	switch (cmd) {
+	case BCH_IOCTL_ASSEMBLE:
+		return bch2_ioctl_assemble(arg);
+	case BCH_IOCTL_INCREMENTAL:
+		return bch2_ioctl_incremental(arg);
+	default:
+		return -ENOTTY;
+	}
+}
+
+static long bch2_ioctl_query_uuid(struct bch_fs *c,
+			struct bch_ioctl_query_uuid __user *user_arg)
+{
+	return copy_to_user(&user_arg->uuid,
+			    &c->sb.user_uuid,
+			    sizeof(c->sb.user_uuid));
+}
+
+static long bch2_ioctl_start(struct bch_fs *c, struct bch_ioctl_start __user *user_arg)
+{
+	struct bch_ioctl_start arg;
+
+	if (copy_from_user(&arg, user_arg, sizeof(arg)))
+		return -EFAULT;
+
+	if (arg.flags || arg.pad)
+		return -EINVAL;
+
+	return bch2_fs_start(c) ? -EIO : 0;
+}
+
+static long bch2_ioctl_stop(struct bch_fs *c)
+{
+	bch2_fs_stop(c);
+	return 0;
+}
+
+/* returns with ref on ca->ref */
+static struct bch_dev *bch2_device_lookup(struct bch_fs *c,
+					 const char __user *dev)
+{
+	struct block_device *bdev;
+	struct bch_dev *ca;
+	char *path;
+	unsigned i;
+
+	path = strndup_user(dev, PATH_MAX);
+	if (!path)
+		return ERR_PTR(-ENOMEM);
+
+	bdev = lookup_bdev(strim(path));
+	kfree(path);
+	if (IS_ERR(bdev))
+		return ERR_CAST(bdev);
+
+	for_each_member_device(ca, c, i)
+		if (ca->disk_sb.bdev == bdev)
+			goto found;
+
+	ca = NULL;
+found:
+	bdput(bdev);
+	return ca;
+}
+
+#if 0
+static struct bch_member *bch2_uuid_lookup(struct bch_fs *c, uuid_le uuid)
+{
+	struct bch_sb_field_members *mi = bch2_sb_get_members(c->disk_sb);
+	unsigned i;
+
+	lockdep_assert_held(&c->sb_lock);
+
+	for (i = 0; i < c->disk_sb->nr_devices; i++)
+		if (!memcmp(&mi->members[i].uuid, &uuid, sizeof(uuid)))
+			return &mi->members[i];
+
+	return NULL;
+}
+#endif
+
+static long bch2_ioctl_disk_add(struct bch_fs *c,
+			struct bch_ioctl_disk __user *user_arg)
+{
+	struct bch_ioctl_disk arg;
+	char *path;
+	int ret;
+
+	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);
+	if (!path)
+		return -ENOMEM;
+
+	ret = bch2_dev_add(c, path);
+	kfree(path);
+
+	return ret;
+}
+
+static long bch2_ioctl_disk_remove(struct bch_fs *c,
+			struct bch_ioctl_disk __user *user_arg)
+{
+	struct bch_ioctl_disk arg;
+	struct bch_dev *ca;
+
+	if (copy_from_user(&arg, user_arg, sizeof(arg)))
+		return -EFAULT;
+
+	ca = bch2_device_lookup(c, (const char __user *)(unsigned long) arg.dev);
+	if (IS_ERR(ca))
+		return PTR_ERR(ca);
+
+	return bch2_dev_remove(c, ca, arg.flags);
+}
+
+static long bch2_ioctl_disk_online(struct bch_fs *c,
+			struct bch_ioctl_disk __user *user_arg)
+{
+	struct bch_ioctl_disk arg;
+	char *path;
+	int ret;
+
+	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);
+	if (!path)
+		return -ENOMEM;
+
+	ret = bch2_dev_online(c, path);
+	kfree(path);
+	return ret;
+}
+
+static long bch2_ioctl_disk_offline(struct bch_fs *c,
+			struct bch_ioctl_disk __user *user_arg)
+{
+	struct bch_ioctl_disk arg;
+	struct bch_dev *ca;
+	int ret;
+
+	if (copy_from_user(&arg, user_arg, sizeof(arg)))
+		return -EFAULT;
+
+	if (arg.pad)
+		return -EINVAL;
+
+	ca = bch2_device_lookup(c, (const char __user *)(unsigned long) arg.dev);
+	if (IS_ERR(ca))
+		return PTR_ERR(ca);
+
+	ret = bch2_dev_offline(c, ca, arg.flags);
+	percpu_ref_put(&ca->ref);
+	return ret;
+}
+
+static long bch2_ioctl_disk_set_state(struct bch_fs *c,
+			struct bch_ioctl_disk_set_state __user *user_arg)
+{
+	struct bch_ioctl_disk_set_state arg;
+	struct bch_dev *ca;
+	int ret;
+
+	if (copy_from_user(&arg, user_arg, sizeof(arg)))
+		return -EFAULT;
+
+	ca = bch2_device_lookup(c, (const char __user *)(unsigned long) arg.dev);
+	if (IS_ERR(ca))
+		return PTR_ERR(ca);
+
+	ret = bch2_dev_set_state(c, ca, arg.new_state, arg.flags);
+
+	percpu_ref_put(&ca->ref);
+	return ret;
+}
+
+static long bch2_ioctl_disk_evacuate(struct bch_fs *c,
+			struct bch_ioctl_disk __user *user_arg)
+{
+	struct bch_ioctl_disk arg;
+	struct bch_dev *ca;
+	int ret;
+
+	if (copy_from_user(&arg, user_arg, sizeof(arg)))
+		return -EFAULT;
+
+	ca = bch2_device_lookup(c, (const char __user *)(unsigned long) arg.dev);
+	if (IS_ERR(ca))
+		return PTR_ERR(ca);
+
+	ret = bch2_dev_evacuate(c, ca);
+
+	percpu_ref_put(&ca->ref);
+	return ret;
+}
+
+long bch2_fs_ioctl(struct bch_fs *c, unsigned cmd, void __user *arg)
+{
+	/* ioctls that don't require admin cap: */
+	switch (cmd) {
+	case BCH_IOCTL_QUERY_UUID:
+		return bch2_ioctl_query_uuid(c, arg);
+	}
+
+	if (!capable(CAP_SYS_ADMIN))
+		return -EPERM;
+
+	/* ioctls that do require admin cap: */
+	switch (cmd) {
+	case BCH_IOCTL_START:
+		return bch2_ioctl_start(c, arg);
+	case BCH_IOCTL_STOP:
+		return bch2_ioctl_stop(c);
+
+	case BCH_IOCTL_DISK_ADD:
+		return bch2_ioctl_disk_add(c, arg);
+	case BCH_IOCTL_DISK_REMOVE:
+		return bch2_ioctl_disk_remove(c, arg);
+	case BCH_IOCTL_DISK_ONLINE:
+		return bch2_ioctl_disk_online(c, arg);
+	case BCH_IOCTL_DISK_OFFLINE:
+		return bch2_ioctl_disk_offline(c, arg);
+	case BCH_IOCTL_DISK_SET_STATE:
+		return bch2_ioctl_disk_set_state(c, arg);
+	case BCH_IOCTL_DISK_EVACUATE:
+		return bch2_ioctl_disk_evacuate(c, arg);
+
+	default:
+		return -ENOTTY;
+	}
+}
+
+static long bch2_chardev_ioctl(struct file *filp, unsigned cmd, unsigned long v)
+{
+	struct bch_fs *c = filp->private_data;
+	void __user *arg = (void __user *) v;
+
+	return c
+		? bch2_fs_ioctl(c, cmd, arg)
+		: bch2_global_ioctl(cmd, arg);
+}
+
+static const struct file_operations bch_chardev_fops = {
+	.owner		= THIS_MODULE,
+	.unlocked_ioctl = bch2_chardev_ioctl,
+	.open		= nonseekable_open,
+};
+
+static int bch_chardev_major;
+static struct class *bch_chardev_class;
+static struct device *bch_chardev;
+static DEFINE_IDR(bch_chardev_minor);
+
+void bch2_fs_chardev_exit(struct bch_fs *c)
+{
+	if (!IS_ERR_OR_NULL(c->chardev))
+		device_unregister(c->chardev);
+	if (c->minor >= 0)
+		idr_remove(&bch_chardev_minor, c->minor);
+}
+
+int bch2_fs_chardev_init(struct bch_fs *c)
+{
+	c->minor = idr_alloc(&bch_chardev_minor, c, 0, 0, GFP_KERNEL);
+	if (c->minor < 0)
+		return c->minor;
+
+	c->chardev = device_create(bch_chardev_class, NULL,
+				   MKDEV(bch_chardev_major, c->minor), NULL,
+				   "bcachefs%u-ctl", c->minor);
+	if (IS_ERR(c->chardev))
+		return PTR_ERR(c->chardev);
+
+	return 0;
+}
+
+void bch2_chardev_exit(void)
+{
+	if (!IS_ERR_OR_NULL(bch_chardev_class))
+		device_destroy(bch_chardev_class,
+			       MKDEV(bch_chardev_major, 255));
+	if (!IS_ERR_OR_NULL(bch_chardev_class))
+		class_destroy(bch_chardev_class);
+	if (bch_chardev_major > 0)
+		unregister_chrdev(bch_chardev_major, "bcachefs");
+}
+
+int __init bch2_chardev_init(void)
+{
+	bch_chardev_major = register_chrdev(0, "bcachefs-ctl", &bch_chardev_fops);
+	if (bch_chardev_major < 0)
+		return bch_chardev_major;
+
+	bch_chardev_class = class_create(THIS_MODULE, "bcachefs");
+	if (IS_ERR(bch_chardev_class))
+		return PTR_ERR(bch_chardev_class);
+
+	bch_chardev = device_create(bch_chardev_class, NULL,
+				    MKDEV(bch_chardev_major, 255),
+				    NULL, "bcachefs-ctl");
+	if (IS_ERR(bch_chardev))
+		return PTR_ERR(bch_chardev);
+
+	return 0;
+}