Btrfs: add basic restriper infrastructure
Add basic restriper infrastructure: extended balancing ioctl and all
related ioctl data structures, add data structure for tracking
restriper's state to fs_info, etc. The semantics of the old balancing
ioctl are fully preserved.
Explicitly disallow any volume operations when balance is in progress.
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index c04f02c..d838d2cf 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -1203,13 +1203,21 @@
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
+ mutex_lock(&root->fs_info->volume_mutex);
+ if (root->fs_info->balance_ctl) {
+ printk(KERN_INFO "btrfs: balance in progress\n");
+ ret = -EINVAL;
+ goto out;
+ }
+
vol_args = memdup_user(arg, sizeof(*vol_args));
- if (IS_ERR(vol_args))
- return PTR_ERR(vol_args);
+ if (IS_ERR(vol_args)) {
+ ret = PTR_ERR(vol_args);
+ goto out;
+ }
vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
- mutex_lock(&root->fs_info->volume_mutex);
sizestr = vol_args->name;
devstr = strchr(sizestr, ':');
if (devstr) {
@@ -1226,7 +1234,7 @@
printk(KERN_INFO "btrfs: resizer unable to find device %llu\n",
(unsigned long long)devid);
ret = -EINVAL;
- goto out_unlock;
+ goto out_free;
}
if (!strcmp(sizestr, "max"))
new_size = device->bdev->bd_inode->i_size;
@@ -1241,7 +1249,7 @@
new_size = memparse(sizestr, NULL);
if (new_size == 0) {
ret = -EINVAL;
- goto out_unlock;
+ goto out_free;
}
}
@@ -1250,7 +1258,7 @@
if (mod < 0) {
if (new_size > old_size) {
ret = -EINVAL;
- goto out_unlock;
+ goto out_free;
}
new_size = old_size - new_size;
} else if (mod > 0) {
@@ -1259,11 +1267,11 @@
if (new_size < 256 * 1024 * 1024) {
ret = -EINVAL;
- goto out_unlock;
+ goto out_free;
}
if (new_size > device->bdev->bd_inode->i_size) {
ret = -EFBIG;
- goto out_unlock;
+ goto out_free;
}
do_div(new_size, root->sectorsize);
@@ -1276,7 +1284,7 @@
trans = btrfs_start_transaction(root, 0);
if (IS_ERR(trans)) {
ret = PTR_ERR(trans);
- goto out_unlock;
+ goto out_free;
}
ret = btrfs_grow_device(trans, device, new_size);
btrfs_commit_transaction(trans, root);
@@ -1284,9 +1292,10 @@
ret = btrfs_shrink_device(device, new_size);
}
-out_unlock:
- mutex_unlock(&root->fs_info->volume_mutex);
+out_free:
kfree(vol_args);
+out:
+ mutex_unlock(&root->fs_info->volume_mutex);
return ret;
}
@@ -2052,14 +2061,25 @@
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
+ mutex_lock(&root->fs_info->volume_mutex);
+ if (root->fs_info->balance_ctl) {
+ printk(KERN_INFO "btrfs: balance in progress\n");
+ ret = -EINVAL;
+ goto out;
+ }
+
vol_args = memdup_user(arg, sizeof(*vol_args));
- if (IS_ERR(vol_args))
- return PTR_ERR(vol_args);
+ if (IS_ERR(vol_args)) {
+ ret = PTR_ERR(vol_args);
+ goto out;
+ }
vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
ret = btrfs_init_new_device(root, vol_args->name);
kfree(vol_args);
+out:
+ mutex_unlock(&root->fs_info->volume_mutex);
return ret;
}
@@ -2074,14 +2094,25 @@
if (root->fs_info->sb->s_flags & MS_RDONLY)
return -EROFS;
+ mutex_lock(&root->fs_info->volume_mutex);
+ if (root->fs_info->balance_ctl) {
+ printk(KERN_INFO "btrfs: balance in progress\n");
+ ret = -EINVAL;
+ goto out;
+ }
+
vol_args = memdup_user(arg, sizeof(*vol_args));
- if (IS_ERR(vol_args))
- return PTR_ERR(vol_args);
+ if (IS_ERR(vol_args)) {
+ ret = PTR_ERR(vol_args);
+ goto out;
+ }
vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
ret = btrfs_rm_device(root, vol_args->name);
kfree(vol_args);
+out:
+ mutex_unlock(&root->fs_info->volume_mutex);
return ret;
}
@@ -3034,6 +3065,76 @@
return ret;
}
+void update_ioctl_balance_args(struct btrfs_fs_info *fs_info,
+ struct btrfs_ioctl_balance_args *bargs)
+{
+ struct btrfs_balance_control *bctl = fs_info->balance_ctl;
+
+ bargs->flags = bctl->flags;
+
+ memcpy(&bargs->data, &bctl->data, sizeof(bargs->data));
+ memcpy(&bargs->meta, &bctl->meta, sizeof(bargs->meta));
+ memcpy(&bargs->sys, &bctl->sys, sizeof(bargs->sys));
+}
+
+static long btrfs_ioctl_balance(struct btrfs_root *root, void __user *arg)
+{
+ struct btrfs_fs_info *fs_info = root->fs_info;
+ struct btrfs_ioctl_balance_args *bargs;
+ struct btrfs_balance_control *bctl;
+ int ret;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ if (fs_info->sb->s_flags & MS_RDONLY)
+ return -EROFS;
+
+ mutex_lock(&fs_info->volume_mutex);
+ mutex_lock(&fs_info->balance_mutex);
+
+ if (arg) {
+ bargs = memdup_user(arg, sizeof(*bargs));
+ if (IS_ERR(bargs)) {
+ ret = PTR_ERR(bargs);
+ goto out;
+ }
+ } else {
+ bargs = NULL;
+ }
+
+ bctl = kzalloc(sizeof(*bctl), GFP_NOFS);
+ if (!bctl) {
+ ret = -ENOMEM;
+ goto out_bargs;
+ }
+
+ bctl->fs_info = fs_info;
+ if (arg) {
+ memcpy(&bctl->data, &bargs->data, sizeof(bctl->data));
+ memcpy(&bctl->meta, &bargs->meta, sizeof(bctl->meta));
+ memcpy(&bctl->sys, &bargs->sys, sizeof(bctl->sys));
+
+ bctl->flags = bargs->flags;
+ }
+
+ ret = btrfs_balance(bctl, bargs);
+ /*
+ * bctl is freed in __cancel_balance
+ */
+ if (arg) {
+ if (copy_to_user(arg, bargs, sizeof(*bargs)))
+ ret = -EFAULT;
+ }
+
+out_bargs:
+ kfree(bargs);
+out:
+ mutex_unlock(&fs_info->balance_mutex);
+ mutex_unlock(&fs_info->volume_mutex);
+ return ret;
+}
+
long btrfs_ioctl(struct file *file, unsigned int
cmd, unsigned long arg)
{
@@ -3078,7 +3179,7 @@
case BTRFS_IOC_DEV_INFO:
return btrfs_ioctl_dev_info(root, argp);
case BTRFS_IOC_BALANCE:
- return btrfs_balance(root->fs_info->dev_root);
+ return btrfs_ioctl_balance(root, NULL);
case BTRFS_IOC_CLONE:
return btrfs_ioctl_clone(file, arg, 0, 0, 0);
case BTRFS_IOC_CLONE_RANGE:
@@ -3110,6 +3211,8 @@
return btrfs_ioctl_scrub_cancel(root, argp);
case BTRFS_IOC_SCRUB_PROGRESS:
return btrfs_ioctl_scrub_progress(root, argp);
+ case BTRFS_IOC_BALANCE_V2:
+ return btrfs_ioctl_balance(root, argp);
}
return -ENOTTY;