Merge tag 'imx-fixes-4.4-2' of git://git.kernel.org/pub/scm/linux/kernel/git/shawnguo...
[firefly-linux-kernel-4.4.55.git] / fs / nfs / nfs4file.c
index b0dbe0abed53631a22e938b332b675b501b9e978..db9b5fea5b3ef12f6eacf36cd2154c2db7d4d9f2 100644 (file)
@@ -4,8 +4,10 @@
  *  Copyright (C) 1992  Rick Sladkey
  */
 #include <linux/fs.h>
+#include <linux/file.h>
 #include <linux/falloc.h>
 #include <linux/nfs_fs.h>
+#include <uapi/linux/btrfs.h>  /* BTRFS_IOC_CLONE/BTRFS_IOC_CLONE_RANGE */
 #include "delegation.h"
 #include "internal.h"
 #include "iostat.h"
@@ -192,14 +194,138 @@ static long nfs42_fallocate(struct file *filep, int mode, loff_t offset, loff_t
                return nfs42_proc_deallocate(filep, offset, len);
        return nfs42_proc_allocate(filep, offset, len);
 }
+
+static noinline long
+nfs42_ioctl_clone(struct file *dst_file, unsigned long srcfd,
+                 u64 src_off, u64 dst_off, u64 count)
+{
+       struct inode *dst_inode = file_inode(dst_file);
+       struct nfs_server *server = NFS_SERVER(dst_inode);
+       struct fd src_file;
+       struct inode *src_inode;
+       unsigned int bs = server->clone_blksize;
+       bool same_inode = false;
+       int ret;
+
+       /* dst file must be opened for writing */
+       if (!(dst_file->f_mode & FMODE_WRITE))
+               return -EINVAL;
+
+       ret = mnt_want_write_file(dst_file);
+       if (ret)
+               return ret;
+
+       src_file = fdget(srcfd);
+       if (!src_file.file) {
+               ret = -EBADF;
+               goto out_drop_write;
+       }
+
+       src_inode = file_inode(src_file.file);
+
+       if (src_inode == dst_inode)
+               same_inode = true;
+
+       /* src file must be opened for reading */
+       if (!(src_file.file->f_mode & FMODE_READ))
+               goto out_fput;
+
+       /* src and dst must be regular files */
+       ret = -EISDIR;
+       if (!S_ISREG(src_inode->i_mode) || !S_ISREG(dst_inode->i_mode))
+               goto out_fput;
+
+       ret = -EXDEV;
+       if (src_file.file->f_path.mnt != dst_file->f_path.mnt ||
+           src_inode->i_sb != dst_inode->i_sb)
+               goto out_fput;
+
+       /* check alignment w.r.t. clone_blksize */
+       ret = -EINVAL;
+       if (bs) {
+               if (!IS_ALIGNED(src_off, bs) || !IS_ALIGNED(dst_off, bs))
+                       goto out_fput;
+               if (!IS_ALIGNED(count, bs) && i_size_read(src_inode) != (src_off + count))
+                       goto out_fput;
+       }
+
+       /* verify if ranges are overlapped within the same file */
+       if (same_inode) {
+               if (dst_off + count > src_off && dst_off < src_off + count)
+                       goto out_fput;
+       }
+
+       /* XXX: do we lock at all? what if server needs CB_RECALL_LAYOUT? */
+       if (same_inode) {
+               mutex_lock(&src_inode->i_mutex);
+       } else if (dst_inode < src_inode) {
+               mutex_lock_nested(&dst_inode->i_mutex, I_MUTEX_PARENT);
+               mutex_lock_nested(&src_inode->i_mutex, I_MUTEX_CHILD);
+       } else {
+               mutex_lock_nested(&src_inode->i_mutex, I_MUTEX_PARENT);
+               mutex_lock_nested(&dst_inode->i_mutex, I_MUTEX_CHILD);
+       }
+
+       /* flush all pending writes on both src and dst so that server
+        * has the latest data */
+       ret = nfs_sync_inode(src_inode);
+       if (ret)
+               goto out_unlock;
+       ret = nfs_sync_inode(dst_inode);
+       if (ret)
+               goto out_unlock;
+
+       ret = nfs42_proc_clone(src_file.file, dst_file, src_off, dst_off, count);
+
+       /* truncate inode page cache of the dst range so that future reads can fetch
+        * new data from server */
+       if (!ret)
+               truncate_inode_pages_range(&dst_inode->i_data, dst_off, dst_off + count - 1);
+
+out_unlock:
+       if (same_inode) {
+               mutex_unlock(&src_inode->i_mutex);
+       } else if (dst_inode < src_inode) {
+               mutex_unlock(&src_inode->i_mutex);
+               mutex_unlock(&dst_inode->i_mutex);
+       } else {
+               mutex_unlock(&dst_inode->i_mutex);
+               mutex_unlock(&src_inode->i_mutex);
+       }
+out_fput:
+       fdput(src_file);
+out_drop_write:
+       mnt_drop_write_file(dst_file);
+       return ret;
+}
+
+static long nfs42_ioctl_clone_range(struct file *dst_file, void __user *argp)
+{
+       struct btrfs_ioctl_clone_range_args args;
+
+       if (copy_from_user(&args, argp, sizeof(args)))
+               return -EFAULT;
+
+       return nfs42_ioctl_clone(dst_file, args.src_fd, args.src_offset,
+                                args.dest_offset, args.src_length);
+}
+
+long nfs4_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+{
+       void __user *argp = (void __user *)arg;
+
+       switch (cmd) {
+       case BTRFS_IOC_CLONE:
+               return nfs42_ioctl_clone(file, arg, 0, 0, 0);
+       case BTRFS_IOC_CLONE_RANGE:
+               return nfs42_ioctl_clone_range(file, argp);
+       }
+
+       return -ENOTTY;
+}
 #endif /* CONFIG_NFS_V4_2 */
 
 const struct file_operations nfs4_file_operations = {
-#ifdef CONFIG_NFS_V4_2
-       .llseek         = nfs4_file_llseek,
-#else
-       .llseek         = nfs_file_llseek,
-#endif
        .read_iter      = nfs_file_read,
        .write_iter     = nfs_file_write,
        .mmap           = nfs_file_mmap,
@@ -211,9 +337,14 @@ const struct file_operations nfs4_file_operations = {
        .flock          = nfs_flock,
        .splice_read    = nfs_file_splice_read,
        .splice_write   = iter_file_splice_write,
-#ifdef CONFIG_NFS_V4_2
-       .fallocate      = nfs42_fallocate,
-#endif /* CONFIG_NFS_V4_2 */
        .check_flags    = nfs_check_flags,
        .setlease       = simple_nosetlease,
+#ifdef CONFIG_NFS_V4_2
+       .llseek         = nfs4_file_llseek,
+       .fallocate      = nfs42_fallocate,
+       .unlocked_ioctl = nfs4_ioctl,
+       .compat_ioctl   = nfs4_ioctl,
+#else
+       .llseek         = nfs_file_llseek,
+#endif
 };