[PATCH 5.19 008/207] smb3: Move the flush out of smb2_copychunk_range() into its callers

From: Greg Kroah-Hartman
Date: Mon Sep 26 2022 - 07:40:05 EST


From: David Howells <dhowells@xxxxxxxxxx>

[ Upstream commit c3a72bb213209adfe981a4a92ea5746a778323e4 ]

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@xxxxxxxxxx>
cc: Ronnie Sahlberg <lsahlber@xxxxxxxxxx>
Signed-off-by: Steve French <stfrench@xxxxxxxxxxxxx>
Stable-dep-of: fa30a81f255a ("smb3: fix temporary data corruption in collapse range")
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
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 8f2e003e0590..2b51f0cbf4d2 100644
--- a/fs/cifs/cifsfs.c
+++ b/fs/cifs/cifsfs.c
@@ -1203,6 +1203,8 @@ 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 e8a8daa82ed7..ef8cb7fbabeb 100644
--- a/fs/cifs/smb2ops.c
+++ b/fs/cifs/smb2ops.c
@@ -1886,17 +1886,8 @@ 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;

@@ -3977,6 +3968,8 @@ 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)
@@ -4004,18 +3997,21 @@ 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);
--
2.35.1