xfs: convert bulkstat to new iwalk infrastructure

Create a new ibulk structure incore to help us deal with bulk inode stat
state tracking and then convert the bulkstat code to use the new iwalk
iterator.  This disentangles inode walking from bulk stat control for
simpler code and enables us to isolate the formatter functions to the
ioctl handling code.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>

1 files changed, 28 insertions, 48 deletions

diff --git a/fs/xfs/xfs_itable.h b/fs/xfs/xfs_itable.h
index 369e3f159d4e..624ffbf8cd85 100644
--- a/fs/xfs/xfs_itable.h
+++ b/fs/xfs/xfs_itable.h
@@ -5,63 +5,43 @@
 #ifndef __XFS_ITABLE_H__
 #define	__XFS_ITABLE_H__
 
-/*
- * xfs_bulkstat() is used to fill in xfs_bstat structures as well as dm_stat
- * structures (by the dmi library). This is a pointer to a formatter function
- * that will iget the inode and fill in the appropriate structure.
- * see xfs_bulkstat_one() and xfs_dm_bulkstat_one() in dmapi_xfs.c
- */
-typedef int (*bulkstat_one_pf)(struct xfs_mount	*mp,
-			       xfs_ino_t	ino,
-			       void		__user *buffer,
-			       int		ubsize,
-			       int		*ubused,
-			       int		*stat);
+/* In-memory representation of a userspace request for batch inode data. */
+struct xfs_ibulk {
+	struct xfs_mount	*mp;
+	void __user		*ubuffer; /* user output buffer */
+	xfs_ino_t		startino; /* start with this inode */
+	unsigned int		icount;   /* number of elements in ubuffer */
+	unsigned int		ocount;   /* number of records returned */
+};
+
+/* Return value that means we want to abort the walk. */
+#define XFS_IBULK_ABORT		(XFS_IWALK_ABORT)
 
 /*
- * Values for stat return value.
+ * Advance the user buffer pointer by one record of the given size.  If the
+ * buffer is now full, return the appropriate error code.
  */
-#define BULKSTAT_RV_NOTHING	0
-#define BULKSTAT_RV_DIDONE	1
-#define BULKSTAT_RV_GIVEUP	2
+static inline int
+xfs_ibulk_advance(
+	struct xfs_ibulk	*breq,
+	size_t			bytes)
+{
+	char __user		*b = breq->ubuffer;
+
+	breq->ubuffer = b + bytes;
+	breq->ocount++;
+	return breq->ocount == breq->icount ? XFS_IBULK_ABORT : 0;
+}
 
 /*
  * Return stat information in bulk (by-inode) for the filesystem.
  */
-int					/* error status */
-xfs_bulkstat(
-	xfs_mount_t	*mp,		/* mount point for filesystem */
-	xfs_ino_t	*lastino,	/* last inode returned */
-	int		*count,		/* size of buffer/count returned */
-	bulkstat_one_pf formatter,	/* func that'd fill a single buf */
-	size_t		statstruct_size,/* sizeof struct that we're filling */
-	char		__user *ubuffer,/* buffer with inode stats */
-	int		*done);		/* 1 if there are more stats to get */
 
-typedef int (*bulkstat_one_fmt_pf)(  /* used size in bytes or negative error */
-	void			__user *ubuffer, /* buffer to write to */
-	int			ubsize,		 /* remaining user buffer sz */
-	int			*ubused,	 /* bytes used by formatter */
-	const xfs_bstat_t	*buffer);        /* buffer to read from */
-
-int
-xfs_bulkstat_one_int(
-	xfs_mount_t		*mp,
-	xfs_ino_t		ino,
-	void			__user *buffer,
-	int			ubsize,
-	bulkstat_one_fmt_pf	formatter,
-	int			*ubused,
-	int			*stat);
+typedef int (*bulkstat_one_fmt_pf)(struct xfs_ibulk *breq,
+		const struct xfs_bstat *bstat);
 
-int
-xfs_bulkstat_one(
-	xfs_mount_t		*mp,
-	xfs_ino_t		ino,
-	void			__user *buffer,
-	int			ubsize,
-	int			*ubused,
-	int			*stat);
+int xfs_bulkstat_one(struct xfs_ibulk *breq, bulkstat_one_fmt_pf formatter);
+int xfs_bulkstat(struct xfs_ibulk *breq, bulkstat_one_fmt_pf formatter);
 
 typedef int (*inumbers_fmt_pf)(
 	void			__user *ubuffer, /* buffer to write to */