Re: [PATCH 07/13] nfsd: allow state with no file to appear in /proc/fs/nfsd/clients/*/states

[Jeff Layton <jlayton@kernel.org>]

On Mon, 2024-01-29 at 14:29 +1100, NeilBrown wrote:
> Change the "show" functions to show some content even if a file cannot
> be found.  This is the case for admin-revoked state.
> This is primarily useful for debugging - to ensure states are being
> removed eventually.
> 
> So change several seq_printf() to seq_puts().  Some of these are needed
> to keep checkpatch happy.  Others were done for consistency.
> 
> Signed-off-by: NeilBrown <neilb@suse.de>
> ---
>  fs/nfsd/nfs4state.c | 118 ++++++++++++++++++++++----------------------
>  1 file changed, 58 insertions(+), 60 deletions(-)
> 
> diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
> index 8db224906864..ef4ec23f7c0d 100644
> --- a/fs/nfsd/nfs4state.c
> +++ b/fs/nfsd/nfs4state.c
> @@ -2554,9 +2554,9 @@ static struct nfs4_client *get_nfsdfs_clp(struct inode *inode)
>  
>  static void seq_quote_mem(struct seq_file *m, char *data, int len)
>  {
> -	seq_printf(m, "\"");
> +	seq_puts(m, "\"");
>  	seq_escape_mem(m, data, len, ESCAPE_HEX | ESCAPE_NAP | ESCAPE_APPEND, "\"\\");
> -	seq_printf(m, "\"");
> +	seq_puts(m, "\"");
>  }
>  
>  static const char *cb_state2str(int state)
> @@ -2597,14 +2597,14 @@ static int client_info_show(struct seq_file *m, void *v)
>  		seq_puts(m, "status: unconfirmed\n");
>  	seq_printf(m, "seconds from last renew: %lld\n",
>  		ktime_get_boottime_seconds() - clp->cl_time);
> -	seq_printf(m, "name: ");
> +	seq_puts(m, "name: ");
>  	seq_quote_mem(m, clp->cl_name.data, clp->cl_name.len);
>  	seq_printf(m, "\nminor version: %d\n", clp->cl_minorversion);
>  	if (clp->cl_nii_domain.data) {
> -		seq_printf(m, "Implementation domain: ");
> +		seq_puts(m, "Implementation domain: ");
>  		seq_quote_mem(m, clp->cl_nii_domain.data,
>  					clp->cl_nii_domain.len);
> -		seq_printf(m, "\nImplementation name: ");
> +		seq_puts(m, "\nImplementation name: ");
>  		seq_quote_mem(m, clp->cl_nii_name.data, clp->cl_nii_name.len);
>  		seq_printf(m, "\nImplementation time: [%lld, %ld]\n",
>  			clp->cl_nii_time.tv_sec, clp->cl_nii_time.tv_nsec);
> @@ -2671,7 +2671,7 @@ static void nfs4_show_superblock(struct seq_file *s, struct nfsd_file *f)
>  
>  static void nfs4_show_owner(struct seq_file *s, struct nfs4_stateowner *oo)
>  {
> -	seq_printf(s, "owner: ");
> +	seq_puts(s, "owner: ");
>  	seq_quote_mem(s, oo->so_owner.data, oo->so_owner.len);
>  }
>  
> @@ -2689,20 +2689,13 @@ static int nfs4_show_open(struct seq_file *s, struct nfs4_stid *st)
>  	struct nfs4_stateowner *oo;
>  	unsigned int access, deny;
>  
> -	if (st->sc_type != SC_TYPE_OPEN && st->sc_type != SC_TYPE_LOCK)
> -		return 0; /* XXX: or SEQ_SKIP? */
>  	ols = openlockstateid(st);
>  	oo = ols->st_stateowner;
>  	nf = st->sc_file;
>  
> -	spin_lock(&nf->fi_lock);
> -	file = find_any_file_locked(nf);
> -	if (!file)
> -		goto out;
> -
> -	seq_printf(s, "- ");
> +	seq_puts(s, "- ");
>  	nfs4_show_stateid(s, &st->sc_stateid);
> -	seq_printf(s, ": { type: open, ");
> +	seq_puts(s, ": { type: open, ");
>  
>  	access = bmap_to_share_mode(ols->st_access_bmap);
>  	deny   = bmap_to_share_mode(ols->st_deny_bmap);
> @@ -2714,14 +2707,17 @@ static int nfs4_show_open(struct seq_file *s, struct nfs4_stid *st)
>  		deny & NFS4_SHARE_ACCESS_READ ? "r" : "-",
>  		deny & NFS4_SHARE_ACCESS_WRITE ? "w" : "-");
>  
> -	nfs4_show_superblock(s, file);
> -	seq_printf(s, ", ");
> -	nfs4_show_fname(s, file);
> -	seq_printf(s, ", ");
> -	nfs4_show_owner(s, oo);
> -	seq_printf(s, " }\n");
> -out:
> +	spin_lock(&nf->fi_lock);
> +	file = find_any_file_locked(nf);
> +	if (file) {
> +		nfs4_show_superblock(s, file);
> +		seq_puts(s, ", ");
> +		nfs4_show_fname(s, file);
> +		seq_puts(s, ", ");
> +	}
>  	spin_unlock(&nf->fi_lock);
> +	nfs4_show_owner(s, oo);
> +	seq_puts(s, " }\n");
>  	return 0;
>  }
>  
> @@ -2735,30 +2731,29 @@ static int nfs4_show_lock(struct seq_file *s, struct nfs4_stid *st)
>  	ols = openlockstateid(st);
>  	oo = ols->st_stateowner;
>  	nf = st->sc_file;
> -	spin_lock(&nf->fi_lock);
> -	file = find_any_file_locked(nf);
> -	if (!file)
> -		goto out;
>  
> -	seq_printf(s, "- ");
> +	seq_puts(s, "- ");
>  	nfs4_show_stateid(s, &st->sc_stateid);
> -	seq_printf(s, ": { type: lock, ");
> +	seq_puts(s, ": { type: lock, ");
>  
> -	/*
> -	 * Note: a lock stateid isn't really the same thing as a lock,
> -	 * it's the locking state held by one owner on a file, and there
> -	 * may be multiple (or no) lock ranges associated with it.
> -	 * (Same for the matter is true of open stateids.)
> -	 */
> +	spin_lock(&nf->fi_lock);
> +	file = find_any_file_locked(nf);
> +	if (file) {
> +		/*
> +		 * Note: a lock stateid isn't really the same thing as a lock,
> +		 * it's the locking state held by one owner on a file, and there
> +		 * may be multiple (or no) lock ranges associated with it.
> +		 * (Same for the matter is true of open stateids.)
> +		 */
>  
> -	nfs4_show_superblock(s, file);
> -	/* XXX: open stateid? */
> -	seq_printf(s, ", ");
> -	nfs4_show_fname(s, file);
> -	seq_printf(s, ", ");
> +		nfs4_show_superblock(s, file);
> +		/* XXX: open stateid? */
> +		seq_puts(s, ", ");
> +		nfs4_show_fname(s, file);
> +		seq_puts(s, ", ");
> +	}
>  	nfs4_show_owner(s, oo);
> -	seq_printf(s, " }\n");
> -out:
> +	seq_puts(s, " }\n");
>  	spin_unlock(&nf->fi_lock);
>  	return 0;
>  }
> @@ -2771,25 +2766,25 @@ static int nfs4_show_deleg(struct seq_file *s, struct nfs4_stid *st)
>  
>  	ds = delegstateid(st);
>  	nf = st->sc_file;
> -	spin_lock(&nf->fi_lock);
> -	file = nf->fi_deleg_file;
> -	if (!file)
> -		goto out;
>  
> -	seq_printf(s, "- ");
> +	seq_puts(s, "- ");
>  	nfs4_show_stateid(s, &st->sc_stateid);
> -	seq_printf(s, ": { type: deleg, ");
> +	seq_puts(s, ": { type: deleg, ");
>  
> -	seq_printf(s, "access: %s, ",
> -		ds->dl_type == NFS4_OPEN_DELEGATE_READ ? "r" : "w");
> +	seq_printf(s, "access: %s",
> +		   ds->dl_type == NFS4_OPEN_DELEGATE_READ ? "r" : "w");
>  
>  	/* XXX: lease time, whether it's being recalled. */
>  
> -	nfs4_show_superblock(s, file);
> -	seq_printf(s, ", ");
> -	nfs4_show_fname(s, file);
> -	seq_printf(s, " }\n");
> -out:
> +	spin_lock(&nf->fi_lock);
> +	file = nf->fi_deleg_file;
> +	if (file) {
> +		seq_puts(s, ", ");
> +		nfs4_show_superblock(s, file);
> +		seq_puts(s, ", ");
> +		nfs4_show_fname(s, file);
> +	}
> +	seq_puts(s, " }\n");
>  	spin_unlock(&nf->fi_lock);
>  	return 0;
>  }
> @@ -2802,16 +2797,19 @@ static int nfs4_show_layout(struct seq_file *s, struct nfs4_stid *st)
>  	ls = container_of(st, struct nfs4_layout_stateid, ls_stid);
>  	file = ls->ls_file;
>  
> -	seq_printf(s, "- ");
> +	seq_puts(s, "- ");
>  	nfs4_show_stateid(s, &st->sc_stateid);
> -	seq_printf(s, ": { type: layout, ");
> +	seq_puts(s, ": { type: layout");
>  
>  	/* XXX: What else would be useful? */
>  
> -	nfs4_show_superblock(s, file);
> -	seq_printf(s, ", ");
> -	nfs4_show_fname(s, file);
> -	seq_printf(s, " }\n");
> +	if (file) {
> +		seq_puts(s, ", ");
> +		nfs4_show_superblock(s, file);
> +		seq_puts(s, ", ");
> +		nfs4_show_fname(s, file);
> +	}
> +	seq_puts(s, " }\n");
>  
>  	return 0;
>  }

Reviewed-by: Jeff Layton <jlayton@kernel.org>