[PATCH v2 4/4] xfs: move all scrub input checking to xfs_scrub_validate

["Darrick J. Wong" <darrick.wong@oracle.com>]

From: Eric Sandeen <sandeen@sandeen.net>

There were ad-hoc checks for some scrub types but not others;
mark each scrub type with ... it's type, and use that to validate
the allowed and/or required input fields.

Moving these checks out of xfs_scrub_setup_ag_header makes it
a thin wrapper, so unwrap it in the process.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
[darrick: add xfs_ prefix to enum, check scrub args after checking type]
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
 fs/xfs/scrub/agheader.c |   17 ------------
 fs/xfs/scrub/common.c   |   10 +------
 fs/xfs/scrub/common.h   |    2 -
 fs/xfs/scrub/quota.c    |    7 -----
 fs/xfs/scrub/rtbitmap.c |   12 +-------
 fs/xfs/scrub/scrub.c    |   68 +++++++++++++++++++++++++++++++++++++++--------
 fs/xfs/scrub/scrub.h    |   11 ++++++++
 7 files changed, 70 insertions(+), 57 deletions(-)

diff --git a/fs/xfs/scrub/agheader.c b/fs/xfs/scrub/agheader.c
index 2a9b4f9..b599358 100644
--- a/fs/xfs/scrub/agheader.c
+++ b/fs/xfs/scrub/agheader.c
@@ -37,23 +37,6 @@
 #include "scrub/common.h"
 #include "scrub/trace.h"
 
-/*
- * Set up scrub to check all the static metadata in each AG.
- * This means the SB, AGF, AGI, and AGFL headers.
- */
-int
-xfs_scrub_setup_ag_header(
-	struct xfs_scrub_context	*sc,
-	struct xfs_inode		*ip)
-{
-	struct xfs_mount		*mp = sc->mp;
-
-	if (sc->sm->sm_agno >= mp->m_sb.sb_agcount ||
-	    sc->sm->sm_ino || sc->sm->sm_gen)
-		return -EINVAL;
-	return xfs_scrub_setup_fs(sc, ip);
-}
-
 /* Walk all the blocks in the AGFL. */
 int
 xfs_scrub_walk_agfl(
diff --git a/fs/xfs/scrub/common.c b/fs/xfs/scrub/common.c
index ac95fe9..98452ad 100644
--- a/fs/xfs/scrub/common.c
+++ b/fs/xfs/scrub/common.c
@@ -472,7 +472,7 @@ xfs_scrub_setup_ag_btree(
 			return error;
 	}
 
-	error = xfs_scrub_setup_ag_header(sc, ip);
+	error = xfs_scrub_setup_fs(sc, ip);
 	if (error)
 		return error;
 
@@ -507,14 +507,6 @@ xfs_scrub_get_inode(
 	struct xfs_inode		*ip = NULL;
 	int				error;
 
-	/*
-	 * If userspace passed us an AG number or a generation number
-	 * without an inode number, they haven't got a clue so bail out
-	 * immediately.
-	 */
-	if (sc->sm->sm_agno || (sc->sm->sm_gen && !sc->sm->sm_ino))
-		return -EINVAL;
-
 	/* We want to scan the inode we already had opened. */
 	if (sc->sm->sm_ino == 0 || sc->sm->sm_ino == ip_in->i_ino) {
 		sc->ip = ip_in;
diff --git a/fs/xfs/scrub/common.h b/fs/xfs/scrub/common.h
index 5c04385..fe12053 100644
--- a/fs/xfs/scrub/common.h
+++ b/fs/xfs/scrub/common.h
@@ -78,8 +78,6 @@ int xfs_scrub_checkpoint_log(struct xfs_mount *mp);
 
 /* Setup functions */
 int xfs_scrub_setup_fs(struct xfs_scrub_context *sc, struct xfs_inode *ip);
-int xfs_scrub_setup_ag_header(struct xfs_scrub_context *sc,
-			      struct xfs_inode *ip);
 int xfs_scrub_setup_ag_allocbt(struct xfs_scrub_context *sc,
 			       struct xfs_inode *ip);
 int xfs_scrub_setup_ag_iallocbt(struct xfs_scrub_context *sc,
diff --git a/fs/xfs/scrub/quota.c b/fs/xfs/scrub/quota.c
index 8e58ba8..d43b654 100644
--- a/fs/xfs/scrub/quota.c
+++ b/fs/xfs/scrub/quota.c
@@ -67,13 +67,6 @@ xfs_scrub_setup_quota(
 {
 	uint				dqtype;
 
-	/*
-	 * If userspace gave us an AG number or inode data, they don't
-	 * know what they're doing.  Get out.
-	 */
-	if (sc->sm->sm_agno || sc->sm->sm_ino || sc->sm->sm_gen)
-		return -EINVAL;
-
 	dqtype = xfs_scrub_quota_to_dqtype(sc);
 	if (dqtype == 0)
 		return -EINVAL;
diff --git a/fs/xfs/scrub/rtbitmap.c b/fs/xfs/scrub/rtbitmap.c
index c6fedb6..6860d5d 100644
--- a/fs/xfs/scrub/rtbitmap.c
+++ b/fs/xfs/scrub/rtbitmap.c
@@ -43,22 +43,14 @@ xfs_scrub_setup_rt(
 	struct xfs_scrub_context	*sc,
 	struct xfs_inode		*ip)
 {
-	struct xfs_mount		*mp = sc->mp;
-	int				error = 0;
-
-	/*
-	 * If userspace gave us an AG number or inode data, they don't
-	 * know what they're doing.  Get out.
-	 */
-	if (sc->sm->sm_agno || sc->sm->sm_ino || sc->sm->sm_gen)
-		return -EINVAL;
+	int				error;
 
 	error = xfs_scrub_setup_fs(sc, ip);
 	if (error)
 		return error;
 
 	sc->ilock_flags = XFS_ILOCK_EXCL | XFS_ILOCK_RTBITMAP;
-	sc->ip = mp->m_rbmip;
+	sc->ip = sc->mp->m_rbmip;
 	xfs_ilock(sc->ip, sc->ilock_flags);
 
 	return 0;
diff --git a/fs/xfs/scrub/scrub.c b/fs/xfs/scrub/scrub.c
index 182d2fe..b98084d 100644
--- a/fs/xfs/scrub/scrub.c
+++ b/fs/xfs/scrub/scrub.c
@@ -129,8 +129,6 @@ xfs_scrub_probe(
 {
 	int				error = 0;
 
-	if (sc->sm->sm_ino || sc->sm->sm_agno)
-		return -EINVAL;
 	if (xfs_scrub_should_terminate(sc, &error))
 		return error;
 
@@ -169,105 +167,129 @@ xfs_scrub_teardown(
 
 static const struct xfs_scrub_meta_ops meta_scrub_ops[] = {
 	[XFS_SCRUB_TYPE_PROBE] = {	/* ioctl presence test */
+		.type	= ST_NONE,
 		.setup	= xfs_scrub_setup_fs,
 		.scrub	= xfs_scrub_probe,
 	},
 	[XFS_SCRUB_TYPE_SB] = {		/* superblock */
-		.setup	= xfs_scrub_setup_ag_header,
+		.type	= ST_PERAG,
+		.setup	= xfs_scrub_setup_fs,
 		.scrub	= xfs_scrub_superblock,
 	},
 	[XFS_SCRUB_TYPE_AGF] = {	/* agf */
-		.setup	= xfs_scrub_setup_ag_header,
+		.type	= ST_PERAG,
+		.setup	= xfs_scrub_setup_fs,
 		.scrub	= xfs_scrub_agf,
 	},
 	[XFS_SCRUB_TYPE_AGFL]= {	/* agfl */
-		.setup	= xfs_scrub_setup_ag_header,
+		.type	= ST_PERAG,
+		.setup	= xfs_scrub_setup_fs,
 		.scrub	= xfs_scrub_agfl,
 	},
 	[XFS_SCRUB_TYPE_AGI] = {	/* agi */
-		.setup	= xfs_scrub_setup_ag_header,
+		.type	= ST_PERAG,
+		.setup	= xfs_scrub_setup_fs,
 		.scrub	= xfs_scrub_agi,
 	},
 	[XFS_SCRUB_TYPE_BNOBT] = {	/* bnobt */
+		.type	= ST_PERAG,
 		.setup	= xfs_scrub_setup_ag_allocbt,
 		.scrub	= xfs_scrub_bnobt,
 	},
 	[XFS_SCRUB_TYPE_CNTBT] = {	/* cntbt */
+		.type	= ST_PERAG,
 		.setup	= xfs_scrub_setup_ag_allocbt,
 		.scrub	= xfs_scrub_cntbt,
 	},
 	[XFS_SCRUB_TYPE_INOBT] = {	/* inobt */
+		.type	= ST_PERAG,
 		.setup	= xfs_scrub_setup_ag_iallocbt,
 		.scrub	= xfs_scrub_inobt,
 	},
 	[XFS_SCRUB_TYPE_FINOBT] = {	/* finobt */
+		.type	= ST_PERAG,
 		.setup	= xfs_scrub_setup_ag_iallocbt,
 		.scrub	= xfs_scrub_finobt,
 		.has	= xfs_sb_version_hasfinobt,
 	},
 	[XFS_SCRUB_TYPE_RMAPBT] = {	/* rmapbt */
+		.type	= ST_PERAG,
 		.setup	= xfs_scrub_setup_ag_rmapbt,
 		.scrub	= xfs_scrub_rmapbt,
 		.has	= xfs_sb_version_hasrmapbt,
 	},
 	[XFS_SCRUB_TYPE_REFCNTBT] = {	/* refcountbt */
+		.type	= ST_PERAG,
 		.setup	= xfs_scrub_setup_ag_refcountbt,
 		.scrub	= xfs_scrub_refcountbt,
 		.has	= xfs_sb_version_hasreflink,
 	},
 	[XFS_SCRUB_TYPE_INODE] = {	/* inode record */
+		.type	= ST_INODE,
 		.setup	= xfs_scrub_setup_inode,
 		.scrub	= xfs_scrub_inode,
 	},
 	[XFS_SCRUB_TYPE_BMBTD] = {	/* inode data fork */
+		.type	= ST_INODE,
 		.setup	= xfs_scrub_setup_inode_bmap,
 		.scrub	= xfs_scrub_bmap_data,
 	},
 	[XFS_SCRUB_TYPE_BMBTA] = {	/* inode attr fork */
+		.type	= ST_INODE,
 		.setup	= xfs_scrub_setup_inode_bmap,
 		.scrub	= xfs_scrub_bmap_attr,
 	},
 	[XFS_SCRUB_TYPE_BMBTC] = {	/* inode CoW fork */
+		.type	= ST_INODE,
 		.setup	= xfs_scrub_setup_inode_bmap,
 		.scrub	= xfs_scrub_bmap_cow,
 	},
 	[XFS_SCRUB_TYPE_DIR] = {	/* directory */
+		.type	= ST_INODE,
 		.setup	= xfs_scrub_setup_directory,
 		.scrub	= xfs_scrub_directory,
 	},
 	[XFS_SCRUB_TYPE_XATTR] = {	/* extended attributes */
+		.type	= ST_INODE,
 		.setup	= xfs_scrub_setup_xattr,
 		.scrub	= xfs_scrub_xattr,
 	},
 	[XFS_SCRUB_TYPE_SYMLINK] = {	/* symbolic link */
+		.type	= ST_INODE,
 		.setup	= xfs_scrub_setup_symlink,
 		.scrub	= xfs_scrub_symlink,
 	},
 	[XFS_SCRUB_TYPE_PARENT] = {	/* parent pointers */
+		.type	= ST_INODE,
 		.setup	= xfs_scrub_setup_parent,
 		.scrub	= xfs_scrub_parent,
 	},
 	[XFS_SCRUB_TYPE_RTBITMAP] = {	/* realtime bitmap */
+		.type	= ST_FS,
 		.setup	= xfs_scrub_setup_rt,
 		.scrub	= xfs_scrub_rtbitmap,
 		.has	= xfs_sb_version_hasrealtime,
 	},
 	[XFS_SCRUB_TYPE_RTSUM] = {	/* realtime summary */
+		.type	= ST_FS,
 		.setup	= xfs_scrub_setup_rt,
 		.scrub	= xfs_scrub_rtsummary,
 		.has	= xfs_sb_version_hasrealtime,
 	},
 	[XFS_SCRUB_TYPE_UQUOTA] = {	/* user quota */
-		.setup = xfs_scrub_setup_quota,
-		.scrub = xfs_scrub_quota,
+		.type	= ST_FS,
+		.setup	= xfs_scrub_setup_quota,
+		.scrub	= xfs_scrub_quota,
 	},
 	[XFS_SCRUB_TYPE_GQUOTA] = {	/* group quota */
-		.setup = xfs_scrub_setup_quota,
-		.scrub = xfs_scrub_quota,
+		.type	= ST_FS,
+		.setup	= xfs_scrub_setup_quota,
+		.scrub	= xfs_scrub_quota,
 	},
 	[XFS_SCRUB_TYPE_PQUOTA] = {	/* project quota */
-		.setup = xfs_scrub_setup_quota,
-		.scrub = xfs_scrub_quota,
+		.type	= ST_FS,
+		.setup	= xfs_scrub_setup_quota,
+		.scrub	= xfs_scrub_quota,
 	},
 };
 
@@ -298,6 +320,7 @@ xfs_scrub_validate_inputs(
 	sm->sm_flags &= ~XFS_SCRUB_FLAGS_OUT;
 	if (sm->sm_flags & ~XFS_SCRUB_FLAGS_IN)
 		goto out;
+	/* sm_reserved[] must be zero */
 	if (memchr_inv(sm->sm_reserved, 0, sizeof(sm->sm_reserved)))
 		goto out;
 
@@ -312,6 +335,27 @@ xfs_scrub_validate_inputs(
 	if (ops->has && !ops->has(&mp->m_sb))
 		goto out;
 
+	error = -EINVAL;
+	/* restricting fields must be appropriate for type */
+	switch (ops->type) {
+	case ST_NONE:
+	case ST_FS:
+		if (sm->sm_ino || sm->sm_gen || sm->sm_agno)
+			goto out;
+		break;
+	case ST_PERAG:
+		if (sm->sm_ino || sm->sm_gen ||
+		    sm->sm_agno >= mp->m_sb.sb_agcount)
+			goto out;
+		break;
+	case ST_INODE:
+		if (sm->sm_agno || (sm->sm_gen && !sm->sm_ino))
+			goto out;
+		break;
+	default:
+		goto out;
+	}
+
 	error = -EOPNOTSUPP;
 	/*
 	 * We won't scrub any filesystem that doesn't have the ability
diff --git a/fs/xfs/scrub/scrub.h b/fs/xfs/scrub/scrub.h
index e9ec041..2a79614 100644
--- a/fs/xfs/scrub/scrub.h
+++ b/fs/xfs/scrub/scrub.h
@@ -22,6 +22,14 @@
 
 struct xfs_scrub_context;
 
+/* Type info and names for the scrub types. */
+enum xfs_scrub_type {
+	ST_NONE = 1,	/* disabled */
+	ST_PERAG,	/* per-AG metadata */
+	ST_FS,		/* per-FS metadata */
+	ST_INODE,	/* per-inode metadata */
+};
+
 struct xfs_scrub_meta_ops {
 	/* Acquire whatever resources are needed for the operation. */
 	int		(*setup)(struct xfs_scrub_context *,
@@ -32,6 +40,9 @@ struct xfs_scrub_meta_ops {
 
 	/* Decide if we even have this piece of metadata. */
 	bool		(*has)(struct xfs_sb *);
+
+	/* type describing required/allowed inputs */
+	enum xfs_scrub_type	type;
 };
 
 /* Buffer pointers and btree cursors for an entire AG. */