nilfs2: implement resize ioctl

This adds resize ioctl which makes online resize possible.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

1 files changed, 27 insertions, 0 deletions

diff --git a/fs/nilfs2/ioctl.c b/fs/nilfs2/ioctl.c
index 6f617773a7f7..41d6743d303c 100644
--- a/fs/nilfs2/ioctl.c
+++ b/fs/nilfs2/ioctl.c
@@ -698,6 +698,31 @@ static int nilfs_ioctl_sync(struct inode *inode, struct file *filp,
         return 0;
 }
 
+static int nilfs_ioctl_resize(struct inode *inode, struct file *filp,
+                              void __user *argp)
+{
+        __u64 newsize;
+        int ret = -EPERM;
+
+        if (!capable(CAP_SYS_ADMIN))
+                goto out;
+
+        ret = mnt_want_write(filp->f_path.mnt);
+        if (ret)
+                goto out;
+
+        ret = -EFAULT;
+        if (copy_from_user(&newsize, argp, sizeof(newsize)))
+                goto out_drop_write;
+
+        ret = nilfs_resize_fs(inode->i_sb, newsize);
+
+out_drop_write:
+        mnt_drop_write(filp->f_path.mnt);
+out:
+        return ret;
+}
+
 static int nilfs_ioctl_set_alloc_range(struct inode *inode, void __user *argp)
 {
         struct the_nilfs *nilfs = inode->i_sb->s_fs_info;
@@ -795,6 +820,8 @@ long nilfs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
                 return nilfs_ioctl_clean_segments(inode, filp, cmd, argp);
         case NILFS_IOCTL_SYNC:
                 return nilfs_ioctl_sync(inode, filp, cmd, argp);
+        case NILFS_IOCTL_RESIZE:
+                return nilfs_ioctl_resize(inode, filp, argp);
         case NILFS_IOCTL_SET_ALLOC_RANGE:
                 return nilfs_ioctl_set_alloc_range(inode, argp);
         default: