smb: client: fix zero rsize error messages

JIRA: https://issues.redhat.com/browse/RHEL-104401
Conflicts:
	- Code difference due to lack of netfslib support in RHEL 9.7.
          The equivalent cifs_prepare_read() function in RHEL 9.7 is
          cifs_send_async_read(), so place the changes there instead.

commit 3965c23
Author: Paulo Alcantara <[email protected]>
Date:   Mon May 12 14:58:36 2025 -0300

    smb: client: fix zero rsize error messages

    cifs_prepare_read() might be called with a disconnected channel, where
    TCP_Server_Info::max_read is set to zero due to reconnect, so calling
    ->negotiate_rize() will set @rsize to default min IO size (64KiB) and
    then logging

            CIFS: VFS: SMB: Zero rsize calculated, using minimum value
            65536

    If the reconnect happens in cifsd thread, cifs_renegotiate_iosize()
    will end up being called and then @rsize set to the expected value.

    Since we can't rely on the value of @server->max_read by the time we
    call cifs_prepare_read(), try to ->negotiate_rize() only if
    @cifs_sb->ctx->rsize is zero.

    Reported-by: Steve French <[email protected]>
    Fixes: c59f7c9 ("smb: client: ensure aligned IO sizes")
    Signed-off-by: Paulo Alcantara (Red Hat) <[email protected]>
    Signed-off-by: Steve French <[email protected]>

Signed-off-by: Paulo Alcantara <[email protected]>

Author: pcacjr

fs/smb/client/file.c

@@ -4185,8 +4185,10 @@ cifs_send_async_read(loff_t offset, size_t len, struct cifsFileInfo *open_file,
 				break;
 		}
 
-		cifs_negotiate_rsize(server, cifs_sb->ctx,
-				     tlink_tcon(open_file->tlink));
+		if (cifs_sb->ctx->rsize == 0) {
+			cifs_negotiate_rsize(server, cifs_sb->ctx,
+					     tlink_tcon(open_file->tlink));
+		}
 
 		rc = server->ops->wait_mtu_credits(server, cifs_sb->ctx->rsize,
 						   &rsize, credits);