1 files changed, 75 insertions, 42 deletions

diff --git a/fs/nfs/nfs4file.c b/fs/nfs/nfs4file.c
index b0dbe0abed53..d0390516467c 100644
--- a/fs/nfs/nfs4file.c
+++ b/fs/nfs/nfs4file.c
@@ -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"
@@ -24,7 +26,7 @@ static int
 nfs4_file_open(struct inode *inode, struct file *filp)
 {
 	struct nfs_open_context *ctx;
-	struct dentry *dentry = filp->f_path.dentry;
+	struct dentry *dentry = file_dentry(filp);
 	struct dentry *parent = NULL;
 	struct inode *dir;
 	unsigned openflags = filp->f_flags;
@@ -55,7 +57,7 @@ nfs4_file_open(struct inode *inode, struct file *filp)
 	parent = dget_parent(dentry);
 	dir = d_inode(parent);
 
-	ctx = alloc_nfs_open_context(filp->f_path.dentry, filp->f_mode);
+	ctx = alloc_nfs_open_context(file_dentry(filp), filp->f_mode);
 	err = PTR_ERR(ctx);
 	if (IS_ERR(ctx))
 		goto out;
@@ -126,37 +128,6 @@ nfs4_file_flush(struct file *file, fl_owner_t id)
 	return vfs_fsync(file, 0);
 }
 
-static int
-nfs4_file_fsync(struct file *file, loff_t start, loff_t end, int datasync)
-{
-	int ret;
-	struct inode *inode = file_inode(file);
-
-	trace_nfs_fsync_enter(inode);
-
-	nfs_inode_dio_wait(inode);
-	do {
-		ret = filemap_write_and_wait_range(inode->i_mapping, start, end);
-		if (ret != 0)
-			break;
-		mutex_lock(&inode->i_mutex);
-		ret = nfs_file_fsync_commit(file, start, end, datasync);
-		if (!ret)
-			ret = pnfs_sync_inode(inode, !!datasync);
-		mutex_unlock(&inode->i_mutex);
-		/*
-		 * If nfs_file_fsync_commit detected a server reboot, then
-		 * resend all dirty pages that might have been covered by
-		 * the NFS_CONTEXT_RESEND_WRITES flag
-		 */
-		start = 0;
-		end = LLONG_MAX;
-	} while (ret == -EAGAIN);
-
-	trace_nfs_fsync_exit(inode, ret);
-	return ret;
-}
-
 #ifdef CONFIG_NFS_V4_2
 static loff_t nfs4_file_llseek(struct file *filep, loff_t offset, int whence)
 {
@@ -192,28 +163,90 @@ 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 int nfs42_clone_file_range(struct file *src_file, loff_t src_off,
+		struct file *dst_file, loff_t dst_off, u64 count)
+{
+	struct inode *dst_inode = file_inode(dst_file);
+	struct nfs_server *server = NFS_SERVER(dst_inode);
+	struct inode *src_inode = file_inode(src_file);
+	unsigned int bs = server->clone_blksize;
+	bool same_inode = false;
+	int ret;
+
+	/* check alignment w.r.t. clone_blksize */
+	ret = -EINVAL;
+	if (bs) {
+		if (!IS_ALIGNED(src_off, bs) || !IS_ALIGNED(dst_off, bs))
+			goto out;
+		if (!IS_ALIGNED(count, bs) && i_size_read(src_inode) != (src_off + count))
+			goto out;
+	}
+
+	if (src_inode == dst_inode)
+		same_inode = true;
+
+	/* XXX: do we lock at all? what if server needs CB_RECALL_LAYOUT? */
+	if (same_inode) {
+		inode_lock(src_inode);
+	} else if (dst_inode < src_inode) {
+		inode_lock_nested(dst_inode, I_MUTEX_PARENT);
+		inode_lock_nested(src_inode, I_MUTEX_CHILD);
+	} else {
+		inode_lock_nested(src_inode, I_MUTEX_PARENT);
+		inode_lock_nested(dst_inode, 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, 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) {
+		inode_unlock(src_inode);
+	} else if (dst_inode < src_inode) {
+		inode_unlock(src_inode);
+		inode_unlock(dst_inode);
+	} else {
+		inode_unlock(dst_inode);
+		inode_unlock(src_inode);
+	}
+out:
+	return ret;
+}
 #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,
 	.open		= nfs4_file_open,
 	.flush		= nfs4_file_flush,
 	.release	= nfs_file_release,
-	.fsync		= nfs4_file_fsync,
+	.fsync		= nfs_file_fsync,
 	.lock		= nfs_lock,
 	.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,
+	.clone_file_range = nfs42_clone_file_range,
+#else
+	.llseek		= nfs_file_llseek,
+#endif
 };