Re: [PATCH][next] xfs: Fix fall-through warnings for Clang

Darrick J. Wong
2021-04-20T23:38:53Z

On Tue, Apr 20, 2021 at 06:06:52PM -0500, Gustavo A. R. Silva wrote:
> In preparation to enable -Wimplicit-fallthrough for Clang, fix
> the following warnings by replacing /* fall through */ comments,
> and its variants, with the new pseudo-keyword macro fallthrough:
>
> fs/xfs/libxfs/xfs_alloc.c:3167:2: warning: unannotated fall-through between switch labels [-Wimplicit-fallthrough]
> fs/xfs/libxfs/xfs_da_btree.c:286:3: warning: unannotated fall-through between switch labels [-Wimplicit-fallthrough]
> fs/xfs/libxfs/xfs_ag_resv.c:346:2: warning: unannotated fall-through between switch labels [-Wimplicit-fallthrough]
> fs/xfs/libxfs/xfs_ag_resv.c:388:2: warning: unannotated fall-through between switch labels [-Wimplicit-fallthrough]
> fs/xfs/xfs_bmap_util.c:246:2: warning: unannotated fall-through between switch labels [-Wimplicit-fallthrough]
> fs/xfs/xfs_export.c:88:2: warning: unannotated fall-through between switch labels [-Wimplicit-fallthrough]
> fs/xfs/xfs_export.c:96:2: warning: unannotated fall-through between switch labels [-Wimplicit-fallthrough]
> fs/xfs/xfs_file.c:867:3: warning: unannotated fall-through between switch labels [-Wimplicit-fallthrough]
> fs/xfs/xfs_ioctl.c:562:2: warning: unannotated fall-through between switch labels [-Wimplicit-fallthrough]
> fs/xfs/xfs_ioctl.c:1548:2: warning: unannotated fall-through between switch labels [-Wimplicit-fallthrough]
> fs/xfs/xfs_iomap.c:1040:2: warning: unannotated fall-through between switch labels [-Wimplicit-fallthrough]
> fs/xfs/xfs_inode.c:852:2: warning: unannotated fall-through between switch labels [-Wimplicit-fallthrough]
> fs/xfs/xfs_log.c:2627:2: warning: unannotated fall-through between switch labels [-Wimplicit-fallthrough]
> fs/xfs/xfs_trans_buf.c:298:2: warning: unannotated fall-through between switch labels [-Wimplicit-fallthrough]
> fs/xfs/scrub/bmap.c:275:2: warning: unannotated fall-through between switch labels [-Wimplicit-fallthrough]
> fs/xfs/scrub/btree.c:48:2: warning: unannotated fall-through between switch labels [-Wimplicit-fallthrough]
> fs/xfs/scrub/common.c:85:2: warning: unannotated fall-through between switch labels [-Wimplicit-fallthrough]
> fs/xfs/scrub/common.c:138:2: warning: unannotated fall-through between switch labels [-Wimplicit-fallthrough]
> fs/xfs/scrub/common.c:698:2: warning: unannotated fall-through between switch labels [-Wimplicit-fallthrough]
> fs/xfs/scrub/dabtree.c:51:2: warning: unannotated fall-through between switch labels [-Wimplicit-fallthrough]
> fs/xfs/scrub/repair.c:951:2: warning: unannotated fall-through between switch labels [-Wimplicit-fallthrough]
>
> Notice that Clang doesn't recognize /* fall through */ comments as
> implicit fall-through markings, so in order to globally enable
> -Wimplicit-fallthrough for Clang, these comments need to be
> replaced with fallthrough; in the whole codebase.
>
> Link: https://github.com/KSPP/linux/issues/115
> Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>

I've already NAKd this twice, so I guess I'll NAK it a third time.

--D

> ---
> fs/xfs/libxfs/xfs_ag_resv.c | 4 ++--
> fs/xfs/libxfs/xfs_alloc.c | 2 +-
> fs/xfs/libxfs/xfs_da_btree.c | 2 +-
> fs/xfs/scrub/bmap.c | 2 +-
> fs/xfs/scrub/btree.c | 2 +-
> fs/xfs/scrub/common.c | 6 +++---
> fs/xfs/scrub/dabtree.c | 2 +-
> fs/xfs/scrub/repair.c | 2 +-
> fs/xfs/xfs_bmap_util.c | 2 +-
> fs/xfs/xfs_export.c | 4 ++--
> fs/xfs/xfs_file.c | 2 +-
> fs/xfs/xfs_inode.c | 2 +-
> fs/xfs/xfs_ioctl.c | 4 ++--
> fs/xfs/xfs_iomap.c | 2 +-
> fs/xfs/xfs_trans_buf.c | 2 +-
> 15 files changed, 20 insertions(+), 20 deletions(-)
>
> diff --git a/fs/xfs/libxfs/xfs_ag_resv.c b/fs/xfs/libxfs/xfs_ag_resv.c
> index 6c5f8d10589c..8c3c99a9bf83 100644
> --- a/fs/xfs/libxfs/xfs_ag_resv.c
> +++ b/fs/xfs/libxfs/xfs_ag_resv.c
> @@ -342,7 +342,7 @@ xfs_ag_resv_alloc_extent(
> break;
> default:
> ASSERT(0);
> - /* fall through */
> + fallthrough;
> case XFS_AG_RESV_NONE:
> field = args->wasdel ? XFS_TRANS_SB_RES_FDBLOCKS :
> XFS_TRANS_SB_FDBLOCKS;
> @@ -384,7 +384,7 @@ xfs_ag_resv_free_extent(
> break;
> default:
> ASSERT(0);
> - /* fall through */
> + fallthrough;
> case XFS_AG_RESV_NONE:
> xfs_trans_mod_sb(tp, XFS_TRANS_SB_FDBLOCKS, (int64_t)len);
> return;
> diff --git a/fs/xfs/libxfs/xfs_alloc.c b/fs/xfs/libxfs/xfs_alloc.c
> index aaa19101bb2a..9eabdeeec492 100644
> --- a/fs/xfs/libxfs/xfs_alloc.c
> +++ b/fs/xfs/libxfs/xfs_alloc.c
> @@ -3163,7 +3163,7 @@ xfs_alloc_vextent(
> }
> args->agbno = XFS_FSB_TO_AGBNO(mp, args->fsbno);
> args->type = XFS_ALLOCTYPE_NEAR_BNO;
> - /* FALLTHROUGH */
> + fallthrough;
> case XFS_ALLOCTYPE_FIRST_AG:
> /*
> * Rotate through the allocation groups looking for a winner.
> diff --git a/fs/xfs/libxfs/xfs_da_btree.c b/fs/xfs/libxfs/xfs_da_btree.c
> index 83ac9771bfb5..747ec77912c3 100644
> --- a/fs/xfs/libxfs/xfs_da_btree.c
> +++ b/fs/xfs/libxfs/xfs_da_btree.c
> @@ -282,7 +282,7 @@ xfs_da3_node_read_verify(
> __this_address);
> break;
> }
> - /* fall through */
> + fallthrough;
> case XFS_DA_NODE_MAGIC:
> fa = xfs_da3_node_verify(bp);
> if (fa)
> diff --git a/fs/xfs/scrub/bmap.c b/fs/xfs/scrub/bmap.c
> index b5ebf1d1b4db..77d5c4a0f09f 100644
> --- a/fs/xfs/scrub/bmap.c
> +++ b/fs/xfs/scrub/bmap.c
> @@ -271,7 +271,7 @@ xchk_bmap_iextent_xref(
> case XFS_DATA_FORK:
> if (xfs_is_reflink_inode(info->sc->ip))
> break;
> - /* fall through */
> + fallthrough;
> case XFS_ATTR_FORK:
> xchk_xref_is_not_shared(info->sc, agbno,
> irec->br_blockcount);
> diff --git a/fs/xfs/scrub/btree.c b/fs/xfs/scrub/btree.c
> index a94bd8122c60..bd1172358964 100644
> --- a/fs/xfs/scrub/btree.c
> +++ b/fs/xfs/scrub/btree.c
> @@ -44,7 +44,7 @@ __xchk_btree_process_error(
> /* Note the badness but don't abort. */
> sc->sm->sm_flags |= errflag;
> *error = 0;
> - /* fall through */
> + fallthrough;
> default:
> if (cur->bc_flags & XFS_BTREE_ROOT_IN_INODE)
> trace_xchk_ifork_btree_op_error(sc, cur, level,
> diff --git a/fs/xfs/scrub/common.c b/fs/xfs/scrub/common.c
> index aa874607618a..ce9a44ea6948 100644
> --- a/fs/xfs/scrub/common.c
> +++ b/fs/xfs/scrub/common.c
> @@ -81,7 +81,7 @@ __xchk_process_error(
> /* Note the badness but don't abort. */
> sc->sm->sm_flags |= errflag;
> *error = 0;
> - /* fall through */
> + fallthrough;
> default:
> trace_xchk_op_error(sc, agno, bno, *error,
> ret_ip);
> @@ -134,7 +134,7 @@ __xchk_fblock_process_error(
> /* Note the badness but don't abort. */
> sc->sm->sm_flags |= errflag;
> *error = 0;
> - /* fall through */
> + fallthrough;
> default:
> trace_xchk_file_op_error(sc, whichfork, offset, *error,
> ret_ip);
> @@ -694,7 +694,7 @@ xchk_get_inode(
> if (error)
> return -ENOENT;
> error = -EFSCORRUPTED;
> - /* fall through */
> + fallthrough;
> default:
> trace_xchk_op_error(sc,
> XFS_INO_TO_AGNO(mp, sc->sm->sm_ino),
> diff --git a/fs/xfs/scrub/dabtree.c b/fs/xfs/scrub/dabtree.c
> index 653f3280e1c1..9f0dbb47c82c 100644
> --- a/fs/xfs/scrub/dabtree.c
> +++ b/fs/xfs/scrub/dabtree.c
> @@ -47,7 +47,7 @@ xchk_da_process_error(
> /* Note the badness but don't abort. */
> sc->sm->sm_flags |= XFS_SCRUB_OFLAG_CORRUPT;
> *error = 0;
> - /* fall through */
> + fallthrough;
> default:
> trace_xchk_file_op_error(sc, ds->dargs.whichfork,
> xfs_dir2_da_to_db(ds->dargs.geo,
> diff --git a/fs/xfs/scrub/repair.c b/fs/xfs/scrub/repair.c
> index c2857d854c83..b8202dd08939 100644
> --- a/fs/xfs/scrub/repair.c
> +++ b/fs/xfs/scrub/repair.c
> @@ -947,7 +947,7 @@ xrep_ino_dqattach(
> xrep_force_quotacheck(sc, XFS_DQTYPE_GROUP);
> if (XFS_IS_PQUOTA_ON(sc->mp) && !sc->ip->i_pdquot)
> xrep_force_quotacheck(sc, XFS_DQTYPE_PROJ);
> - /* fall through */
> + fallthrough;
> case -ESRCH:
> error = 0;
> break;
> diff --git a/fs/xfs/xfs_bmap_util.c b/fs/xfs/xfs_bmap_util.c
> index a5e9d7d34023..cc628475f9b6 100644
> --- a/fs/xfs/xfs_bmap_util.c
> +++ b/fs/xfs/xfs_bmap_util.c
> @@ -242,7 +242,7 @@ xfs_bmap_count_blocks(
> */
> *count += btblocks - 1;
>
> - /* fall through */
> + fallthrough;
> case XFS_DINODE_FMT_EXTENTS:
> *nextents = xfs_bmap_count_leaves(ifp, count);
> break;
> diff --git a/fs/xfs/xfs_export.c b/fs/xfs/xfs_export.c
> index 465fd9e048d4..1da59bdff245 100644
> --- a/fs/xfs/xfs_export.c
> +++ b/fs/xfs/xfs_export.c
> @@ -84,7 +84,7 @@ xfs_fs_encode_fh(
> case FILEID_INO32_GEN_PARENT:
> fid->i32.parent_ino = XFS_I(parent)->i_ino;
> fid->i32.parent_gen = parent->i_generation;
> - /*FALLTHRU*/
> + fallthrough;
> case FILEID_INO32_GEN:
> fid->i32.ino = XFS_I(inode)->i_ino;
> fid->i32.gen = inode->i_generation;
> @@ -92,7 +92,7 @@ xfs_fs_encode_fh(
> case FILEID_INO32_GEN_PARENT | XFS_FILEID_TYPE_64FLAG:
> fid64->parent_ino = XFS_I(parent)->i_ino;
> fid64->parent_gen = parent->i_generation;
> - /*FALLTHRU*/
> + fallthrough;
> case FILEID_INO32_GEN | XFS_FILEID_TYPE_64FLAG:
> fid64->ino = XFS_I(inode)->i_ino;
> fid64->gen = inode->i_generation;
> diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c
> index 396ef36dcd0a..3c0749ab9e40 100644
> --- a/fs/xfs/xfs_file.c
> +++ b/fs/xfs/xfs_file.c
> @@ -863,7 +863,7 @@ xfs_break_layouts(
> error = xfs_break_dax_layouts(inode, &retry);
> if (error || retry)
> break;
> - /* fall through */
> + fallthrough;
> case BREAK_WRITE:
> error = xfs_break_leased_layouts(inode, iolock, &retry);
> break;
> diff --git a/fs/xfs/xfs_inode.c b/fs/xfs/xfs_inode.c
> index 0369eb22c1bb..f2846997c3a8 100644
> --- a/fs/xfs/xfs_inode.c
> +++ b/fs/xfs/xfs_inode.c
> @@ -848,7 +848,7 @@ xfs_init_new_inode(
> xfs_inode_inherit_flags(ip, pip);
> if (pip && (pip->i_diflags2 & XFS_DIFLAG2_ANY))
> xfs_inode_inherit_flags2(ip, pip);
> - /* FALLTHROUGH */
> + fallthrough;
> case S_IFLNK:
> ip->i_df.if_format = XFS_DINODE_FMT_EXTENTS;
> ip->i_df.if_bytes = 0;
> diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c
> index 3925bfcb2365..c4dc6c72ac37 100644
> --- a/fs/xfs/xfs_ioctl.c
> +++ b/fs/xfs/xfs_ioctl.c
> @@ -558,7 +558,7 @@ xfs_ioc_attrmulti_one(
> case ATTR_OP_REMOVE:
> value = NULL;
> *len = 0;
> - /* fall through */
> + fallthrough;
> case ATTR_OP_SET:
> error = mnt_want_write_file(parfilp);
> if (error)
> @@ -1544,7 +1544,7 @@ xfs_ioc_getbmap(
> switch (cmd) {
> case XFS_IOC_GETBMAPA:
> bmx.bmv_iflags = BMV_IF_ATTRFORK;
> - /*FALLTHRU*/
> + fallthrough;
> case XFS_IOC_GETBMAP:
> /* struct getbmap is a strict subset of struct getbmapx. */
> recsize = sizeof(struct getbmap);
> diff --git a/fs/xfs/xfs_iomap.c b/fs/xfs/xfs_iomap.c
> index d154f42e2dc6..d8cd2583dedb 100644
> --- a/fs/xfs/xfs_iomap.c
> +++ b/fs/xfs/xfs_iomap.c
> @@ -1036,7 +1036,7 @@ xfs_buffered_write_iomap_begin(
> prealloc_blocks = 0;
> goto retry;
> }
> - /*FALLTHRU*/
> + fallthrough;
> default:
> goto out_unlock;
> }
> diff --git a/fs/xfs/xfs_trans_buf.c b/fs/xfs/xfs_trans_buf.c
> index 9aced0a00003..d11d032da0b4 100644
> --- a/fs/xfs/xfs_trans_buf.c
> +++ b/fs/xfs/xfs_trans_buf.c
> @@ -294,7 +294,7 @@ xfs_trans_read_buf_map(
> default:
> if (tp && (tp->t_flags & XFS_TRANS_DIRTY))
> xfs_force_shutdown(tp->t_mountp, SHUTDOWN_META_IO_ERROR);
> - /* fall through */
> + fallthrough;
> case -ENOMEM:
> case -EAGAIN:
> return error;
> --
> 2.27.0
>