6.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: David Howells <dhowells@xxxxxxxxxx> [ Upstream commit 3758c485f6c9124d8ad76b88382004cbc28a0892 ] Set zero_point in the copy_file_range() and remap_file_range() implementations so that we don't skip reading data modified on a server-side copy. Signed-off-by: David Howells <dhowells@xxxxxxxxxx> cc: Steve French <sfrench@xxxxxxxxx> cc: Shyam Prasad N <nspmangalore@xxxxxxxxx> cc: Rohith Surabattula <rohiths.msft@xxxxxxxxx> cc: Jeff Layton <jlayton@xxxxxxxxxx> cc: linux-cifs@xxxxxxxxxxxxxxx cc: netfs@xxxxxxxxxxxxxxx cc: linux-fsdevel@xxxxxxxxxxxxxxx cc: linux-mm@xxxxxxxxx Stable-dep-of: 93a43155127f ("cifs: Fix missing set of remote_i_size") Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- fs/smb/client/cifsfs.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/fs/smb/client/cifsfs.c b/fs/smb/client/cifsfs.c index 39277c37185ca..c8449f43856c5 100644 --- a/fs/smb/client/cifsfs.c +++ b/fs/smb/client/cifsfs.c @@ -1342,6 +1342,8 @@ static loff_t cifs_remap_file_range(struct file *src_file, loff_t off, rc = cifs_flush_folio(target_inode, destend, &fstart, &fend, false); if (rc) goto unlock; + if (fend > target_cifsi->netfs.zero_point) + target_cifsi->netfs.zero_point = fend + 1; /* Discard all the folios that overlap the destination region. */ cifs_dbg(FYI, "about to discard pages %llx-%llx\n", fstart, fend); @@ -1360,6 +1362,8 @@ static loff_t cifs_remap_file_range(struct file *src_file, loff_t off, fscache_resize_cookie(cifs_inode_cookie(target_inode), new_size); } + if (rc == 0 && new_size > target_cifsi->netfs.zero_point) + target_cifsi->netfs.zero_point = new_size; } /* force revalidate of size and timestamps of target file now @@ -1451,6 +1455,8 @@ ssize_t cifs_file_copychunk_range(unsigned int xid, rc = cifs_flush_folio(target_inode, destend, &fstart, &fend, false); if (rc) goto unlock; + if (fend > target_cifsi->netfs.zero_point) + target_cifsi->netfs.zero_point = fend + 1; /* Discard all the folios that overlap the destination region. */ truncate_inode_pages_range(&target_inode->i_data, fstart, fend); -- 2.43.0