2021-04-14 16:41:48

by Trond Myklebust

[permalink] [raw]
Subject: [PATCH 1/2] NFSv42: Copy offload should update the file size when appropriate

From: Trond Myklebust <[email protected]>

If the result of a copy offload or clone operation is to grow the
destination file size, then we should update it. The reason is that when
a client holds a delegation, it is authoritative for the file size.

Signed-off-by: Trond Myklebust <[email protected]>
---
fs/nfs/nfs42proc.c | 41 ++++++++++++++++++++++++++++++++---------
1 file changed, 32 insertions(+), 9 deletions(-)

diff --git a/fs/nfs/nfs42proc.c b/fs/nfs/nfs42proc.c
index 8d64eb953347..3875120ef3ef 100644
--- a/fs/nfs/nfs42proc.c
+++ b/fs/nfs/nfs42proc.c
@@ -269,6 +269,33 @@ static int process_copy_commit(struct file *dst, loff_t pos_dst,
return status;
}

+/**
+ * nfs42_copy_dest_done - perform inode cache updates after clone/copy offload
+ * @inode: pointer to destination inode
+ * @pos: destination offset
+ * @len: copy length
+ *
+ * Punch a hole in the inode page cache, so that the NFS client will
+ * know to retrieve new data.
+ * Update the file size if necessary, and then mark the inode as having
+ * invalid cached values for change attribute, ctime, mtime and space used.
+ */
+static void nfs42_copy_dest_done(struct inode *inode, loff_t pos, loff_t len)
+{
+ loff_t newsize = pos + len;
+ loff_t end = newsize - 1;
+
+ truncate_pagecache_range(inode, pos, end);
+ spin_lock(&inode->i_lock);
+ if (newsize > i_size_read(inode))
+ i_size_write(inode, newsize);
+ nfs_set_cache_invalid(inode, NFS_INO_INVALID_CHANGE |
+ NFS_INO_INVALID_CTIME |
+ NFS_INO_INVALID_MTIME |
+ NFS_INO_INVALID_BLOCKS);
+ spin_unlock(&inode->i_lock);
+}
+
static ssize_t _nfs42_proc_copy(struct file *src,
struct nfs_lock_context *src_lock,
struct file *dst,
@@ -362,14 +389,8 @@ static ssize_t _nfs42_proc_copy(struct file *src,
goto out;
}

- truncate_pagecache_range(dst_inode, pos_dst,
- pos_dst + res->write_res.count);
- spin_lock(&dst_inode->i_lock);
- nfs_set_cache_invalid(
- dst_inode, NFS_INO_REVAL_PAGECACHE | NFS_INO_REVAL_FORCED |
- NFS_INO_INVALID_SIZE | NFS_INO_INVALID_ATTR |
- NFS_INO_INVALID_DATA);
- spin_unlock(&dst_inode->i_lock);
+ nfs42_copy_dest_done(dst_inode, pos_dst, res->write_res.count);
+
spin_lock(&src_inode->i_lock);
nfs_set_cache_invalid(src_inode, NFS_INO_REVAL_PAGECACHE |
NFS_INO_REVAL_FORCED |
@@ -1055,8 +1076,10 @@ static int _nfs42_proc_clone(struct rpc_message *msg, struct file *src_f,

status = nfs4_call_sync(server->client, server, msg,
&args.seq_args, &res.seq_res, 0);
- if (status == 0)
+ if (status == 0) {
+ nfs42_copy_dest_done(dst_inode, dst_offset, count);
status = nfs_post_op_update_inode(dst_inode, res.dst_fattr);
+ }

kfree(res.dst_fattr);
return status;
--
2.30.2