[PATCH] cifs: Convert to use the fallthrough macro

[PATCH] cifs: Convert to use the fallthrough macro

[linmiaohe]

From: Miaohe Lin <linmiaohe@huawei.com>

Convert the uses of fallthrough comments to fallthrough macro.

Signed-off-by: Hongxiang Lou <louhongxiang@huawei.com>
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
---
 fs/cifs/smb2pdu.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c
index 24c2ac360591..667d70aa335f 100644
--- a/fs/cifs/smb2pdu.c
+++ b/fs/cifs/smb2pdu.c
@@ -3913,7 +3913,7 @@ smb2_readv_callback(struct mid_q_entry *mid)
 	case MID_RESPONSE_MALFORMED:
 		credits.value = le16_to_cpu(shdr->CreditRequest);
 		credits.instance = server->reconnect_instance;
-		/* fall through */
+		fallthrough;
 	default:
 		rdata->result = -EIO;
 	}
@@ -4146,7 +4146,7 @@ smb2_writev_callback(struct mid_q_entry *mid)
 	case MID_RESPONSE_MALFORMED:
 		credits.value = le16_to_cpu(rsp->sync_hdr.CreditRequest);
 		credits.instance = server->reconnect_instance;
-		/* fall through */
+		fallthrough;
 	default:
 		wdata->result = -EIO;
 		break;
-- 
2.19.1

Re: [PATCH] cifs: Convert to use the fallthrough macro

[Steve French]

Is this conversion from "/* Fallthrough */"   to the preferred (?)
"fallthrough;" documented anywhere?

All I see is a few fs changesets like:

commit c730ae0c6bb3125ccb776fb2ab6abbdff500c02c
Author: Marcos Paulo de Souza <mpdesouza@suse.com>
Date:   Tue Jun 16 15:54:29 2020 -0300

    btrfs: convert comments to fallthrough annotations

    Convert fall through comments to the pseudo-keyword which is now the
    preferred way.

And the vast majority of places (33 vs. 4) use "/* Fallthrough */ in
the fs directory

On Sat, Aug 8, 2020 at 3:34 AM linmiaohe <linmiaohe@huawei.com> wrote:
>
> From: Miaohe Lin <linmiaohe@huawei.com>
>
> Convert the uses of fallthrough comments to fallthrough macro.
>
> Signed-off-by: Hongxiang Lou <louhongxiang@huawei.com>
> Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
> ---
>  fs/cifs/smb2pdu.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c
> index 24c2ac360591..667d70aa335f 100644
> --- a/fs/cifs/smb2pdu.c
> +++ b/fs/cifs/smb2pdu.c
> @@ -3913,7 +3913,7 @@ smb2_readv_callback(struct mid_q_entry *mid)
>         case MID_RESPONSE_MALFORMED:
>                 credits.value = le16_to_cpu(shdr->CreditRequest);
>                 credits.instance = server->reconnect_instance;
> -               /* fall through */
> +               fallthrough;
>         default:
>                 rdata->result = -EIO;
>         }
> @@ -4146,7 +4146,7 @@ smb2_writev_callback(struct mid_q_entry *mid)
>         case MID_RESPONSE_MALFORMED:
>                 credits.value = le16_to_cpu(rsp->sync_hdr.CreditRequest);
>                 credits.instance = server->reconnect_instance;
> -               /* fall through */
> +               fallthrough;
>         default:
>                 wdata->result = -EIO;
>                 break;
> --
> 2.19.1
>


-- 
Thanks,

Steve

Re: [PATCH] cifs: Convert to use the fallthrough macro

[Joe Perches]

On Sun, 2020-08-09 at 11:46 -0500, Steve French wrote:
> Is this conversion from "/* Fallthrough */"   to the preferred (?)
> "fallthrough;" documented anywhere?

Documentation/process/deprecated.rst

As there have been a long list of flaws `due to missing "break" statements
<https://cwe.mitre.org/data/definitions/484.html>`_, we no longer allow
implicit fall-through. In order to identify intentional fall-through
cases, we have adopted a pseudo-keyword macro "fallthrough" which
expands to gcc's extension `__attribute__((__fallthrough__))
<https://gcc.gnu.org/onlinedocs/gcc/Statement-Attributes.html>`_.

Re: [PATCH] cifs: Convert to use the fallthrough macro

[Steve French]

merged into cifs-2.6.git for-next

(but note that most places in fs directory other than cifs and btrfs
have not been updated), and I noticed another 8 places in fs/cifs that
you didn't change in your patch (ie change from the older way of
indicating fallthrough   /* Fallthrough */ as a comment to the newer
fallthrough macro.

On Sat, Aug 8, 2020 at 3:34 AM linmiaohe <linmiaohe@huawei.com> wrote:
>
> From: Miaohe Lin <linmiaohe@huawei.com>
>
> Convert the uses of fallthrough comments to fallthrough macro.
>
> Signed-off-by: Hongxiang Lou <louhongxiang@huawei.com>
> Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
> ---
>  fs/cifs/smb2pdu.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c
> index 24c2ac360591..667d70aa335f 100644
> --- a/fs/cifs/smb2pdu.c
> +++ b/fs/cifs/smb2pdu.c
> @@ -3913,7 +3913,7 @@ smb2_readv_callback(struct mid_q_entry *mid)
>         case MID_RESPONSE_MALFORMED:
>                 credits.value = le16_to_cpu(shdr->CreditRequest);
>                 credits.instance = server->reconnect_instance;
> -               /* fall through */
> +               fallthrough;
>         default:
>                 rdata->result = -EIO;
>         }
> @@ -4146,7 +4146,7 @@ smb2_writev_callback(struct mid_q_entry *mid)
>         case MID_RESPONSE_MALFORMED:
>                 credits.value = le16_to_cpu(rsp->sync_hdr.CreditRequest);
>                 credits.instance = server->reconnect_instance;
> -               /* fall through */
> +               fallthrough;
>         default:
>                 wdata->result = -EIO;
>                 break;
> --
> 2.19.1
>


-- 
Thanks,

Steve

Re: [PATCH] cifs: Convert to use the fallthrough macro

[linmiaohe]

Steve French <smfrench@gmail.com> wrote:
>
>merged into cifs-2.6.git for-next
>

Many thanks.

> (but note that most places in fs directory other than cifs and btrfs have not been updated), and I noticed another 8 places in fs/cifs that you didn't change in your patch (ie change from the older way of
>indicating fallthrough   /* Fallthrough */ as a comment to the newer
>fallthrough macro.
>

I'am sorry, I missed that. I would fix another 8 places in fs/cifs soon.
Thanks.

>
>--
>Thanks,
>
>Steve