linux-kernel - [PATCH 1/5] smb3: Move the flush out of smb2_copychunk

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Date:   Tue, 23 Aug 2022 14:07:28 +0100
From:   David Howells <dhowells@...hat.com>
To:     sfrench@...ba.org, linux-cifs@...r.kernel.org
Cc:     lsahlber@...hat.com, jlayton@...nel.org, dchinner@...hat.com,
        willy@...radead.org, linux-fsdevel@...r.kernel.org,
        linux-kernel@...r.kernel.org, samba-technical@...ts.samba.org
Subject: [PATCH 1/5] smb3: Move the flush out of smb2_copychunk_range() into
 its callers

Move the flush out of smb2_copychunk_range() into its callers.  This will
allow the pagecache to be invalidated between the flush and the operation
in smb3_collapse_range() and smb3_insert_range().

Signed-off-by: David Howells <dhowells@...hat.com>
cc: Steve French <stfrench@...rosoft.com>
cc: Ronnie Sahlberg <lsahlber@...hat.com>
---

 fs/cifs/cifsfs.c  |    2 ++
 fs/cifs/smb2ops.c |   20 ++++++++------------
 2 files changed, 10 insertions(+), 12 deletions(-)

diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c
index f54d8bf2732a..e9fb338b8e7e 100644
--- a/fs/cifs/cifsfs.c
+++ b/fs/cifs/cifsfs.c
@@ -1219,6 +1219,8 @@ ssize_t cifs_file_copychunk_range(unsigned int xid,
 
 	cifs_dbg(FYI, "copychunk range\n");
 
+	filemap_write_and_wait(src_inode->i_mapping);
+
 	if (!src_file->private_data || !dst_file->private_data) {
 		rc = -EBADF;
 		cifs_dbg(VFS, "missing cifsFileInfo on copy range src file\n");
diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c
index 96f3b0573606..7e3de6a0e1dc 100644
--- a/fs/cifs/smb2ops.c
+++ b/fs/cifs/smb2ops.c
@@ -1600,17 +1600,8 @@ smb2_copychunk_range(const unsigned int xid,
 	int chunks_copied = 0;
 	bool chunk_sizes_updated = false;
 	ssize_t bytes_written, total_bytes_written = 0;
-	struct inode *inode;
 
 	pcchunk = kmalloc(sizeof(struct copychunk_ioctl), GFP_KERNEL);
-
-	/*
-	 * We need to flush all unwritten data before we can send the
-	 * copychunk ioctl to the server.
-	 */
-	inode = d_inode(trgtfile->dentry);
-	filemap_write_and_wait(inode->i_mapping);
-
 	if (pcchunk == NULL)
 		return -ENOMEM;
 
@@ -3689,6 +3680,8 @@ static long smb3_collapse_range(struct file *file, struct cifs_tcon *tcon,
 		goto out;
 	}
 
+	filemap_write_and_wait(inode->i_mapping);
+
 	rc = smb2_copychunk_range(xid, cfile, cfile, off + len,
 				  i_size_read(inode) - off - len, off);
 	if (rc < 0)
@@ -3716,18 +3709,21 @@ static long smb3_insert_range(struct file *file, struct cifs_tcon *tcon,
 	int rc;
 	unsigned int xid;
 	struct cifsFileInfo *cfile = file->private_data;
+	struct inode *inode = file_inode(file);
 	__le64 eof;
 	__u64  count;
 
 	xid = get_xid();
 
-	if (off >= i_size_read(file->f_inode)) {
+	if (off >= i_size_read(inode)) {
 		rc = -EINVAL;
 		goto out;
 	}
 
-	count = i_size_read(file->f_inode) - off;
-	eof = cpu_to_le64(i_size_read(file->f_inode) + len);
+	count = i_size_read(inode) - off;
+	eof = cpu_to_le64(i_size_read(inode) + len);
+
+	filemap_write_and_wait(inode->i_mapping);
 
 	rc = SMB2_set_eof(xid, tcon, cfile->fid.persistent_fid,
 			  cfile->fid.volatile_fid, cfile->pid, &eof);