[XFS] use filldir internally

Currently xfs has a rather complicated internal scheme to allow for
different directory formats in IRIX. This patch rips all code related to
this out and pushes useage of the Linux filldir callback into the lowlevel
directory code. This does not make the code any less portable because
filldir can be used to create dirents of all possible variations
(including the IRIX ones as proved by the IRIX binary emulation code under
arch/mips/).

This patch get rid of an unessecary copy in the readdir path, about 400
lines of code and one of the last two users of the uio structure.

This version is updated to deal with dmapi aswell which greatly simplifies
the get_dirattrs code. The dmapi part has been tested using the
get_dirattrs tools from the xfstest dmapi suite1 with various small and
large directories.

SGI-PV: 968563
SGI-Modid: xfs-linux-melb:xfs-kern:29478a

Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: David Chinner <dgc@sgi.com>
Signed-off-by: Tim Shimmin <tes@sgi.com>

1 files changed, 18 insertions, 103 deletions

diff --git a/fs/xfs/xfs_dir2.c b/fs/xfs/xfs_dir2.c
index 29e091914df..c2d2bef26cb 100644
--- a/fs/xfs/xfs_dir2.c
+++ b/fs/xfs/xfs_dir2.c
@@ -43,8 +43,6 @@
 #include "xfs_dir2_trace.h"
 #include "xfs_error.h"
 
-static int	xfs_dir2_put_dirent64_direct(xfs_dir2_put_args_t *pa);
-static int	xfs_dir2_put_dirent64_uio(xfs_dir2_put_args_t *pa);
 
 void
 xfs_dir_mount(
@@ -293,47 +291,35 @@ xfs_dir_removename(
  * Read a directory.
  */
 int
-xfs_dir_getdents(
-	xfs_trans_t	*tp,
-	xfs_inode_t	*dp,
-	uio_t		*uio,		/* caller's buffer control */
-	int		*eofp)		/* out: eof reached */
+xfs_readdir(
+	bhv_desc_t	*dir_bdp,
+	void		*dirent,
+	size_t		bufsize,
+	xfs_off_t	*offset,
+	filldir_t	filldir)
 {
-	int		alignment;	/* alignment required for ABI */
-	xfs_dirent_t	*dbp;		/* malloc'ed buffer */
-	xfs_dir2_put_t	put;		/* entry formatting routine */
+	xfs_inode_t	*dp = XFS_BHVTOI(dir_bdp);
 	int		rval;		/* return value */
 	int		v;		/* type-checking value */
 
+	vn_trace_entry(BHV_TO_VNODE(dir_bdp), __FUNCTION__,
+					       (inst_t *)__return_address);
+
+	if (XFS_FORCED_SHUTDOWN(dp->i_mount))
+		return XFS_ERROR(EIO);
+
 	ASSERT((dp->i_d.di_mode & S_IFMT) == S_IFDIR);
 	XFS_STATS_INC(xs_dir_getdents);
-	/*
-	 * If our caller has given us a single contiguous aligned memory buffer,
-	 * just work directly within that buffer.  If it's in user memory,
-	 * lock it down first.
-	 */
-	alignment = sizeof(xfs_off_t) - 1;
-	if ((uio->uio_iovcnt == 1) &&
-	    (((__psint_t)uio->uio_iov[0].iov_base & alignment) == 0) &&
-	    ((uio->uio_iov[0].iov_len & alignment) == 0)) {
-		dbp = NULL;
-		put = xfs_dir2_put_dirent64_direct;
-	} else {
-		dbp = kmem_alloc(sizeof(*dbp) + MAXNAMELEN, KM_SLEEP);
-		put = xfs_dir2_put_dirent64_uio;
-	}
 
-	*eofp = 0;
 	if (dp->i_d.di_format == XFS_DINODE_FMT_LOCAL)
-		rval = xfs_dir2_sf_getdents(dp, uio, eofp, dbp, put);
-	else if ((rval = xfs_dir2_isblock(tp, dp, &v)))
+		rval = xfs_dir2_sf_getdents(dp, dirent, offset, filldir);
+	else if ((rval = xfs_dir2_isblock(NULL, dp, &v)))
 		;
 	else if (v)
-		rval = xfs_dir2_block_getdents(tp, dp, uio, eofp, dbp, put);
+		rval = xfs_dir2_block_getdents(dp, dirent, offset, filldir);
 	else
-		rval = xfs_dir2_leaf_getdents(tp, dp, uio, eofp, dbp, put);
-	if (dbp != NULL)
-		kmem_free(dbp, sizeof(*dbp) + MAXNAMELEN);
+		rval = xfs_dir2_leaf_getdents(dp, dirent, bufsize, offset,
+					      filldir);
 	return rval;
 }
 
@@ -613,77 +599,6 @@ xfs_dir2_isleaf(
 }
 
 /*
- * Getdents put routine for 64-bit ABI, direct form.
- */
-static int
-xfs_dir2_put_dirent64_direct(
-	xfs_dir2_put_args_t	*pa)
-{
-	xfs_dirent_t		*idbp;		/* dirent pointer */
-	iovec_t			*iovp;		/* io vector */
-	int			namelen;	/* entry name length */
-	int			reclen;		/* entry total length */
-	uio_t			*uio;		/* I/O control */
-
-	namelen = pa->namelen;
-	reclen = DIRENTSIZE(namelen);
-	uio = pa->uio;
-	/*
-	 * Won't fit in the remaining space.
-	 */
-	if (reclen > uio->uio_resid) {
-		pa->done = 0;
-		return 0;
-	}
-	iovp = uio->uio_iov;
-	idbp = (xfs_dirent_t *)iovp->iov_base;
-	iovp->iov_base = (char *)idbp + reclen;
-	iovp->iov_len -= reclen;
-	uio->uio_resid -= reclen;
-	idbp->d_reclen = reclen;
-	idbp->d_ino = pa->ino;
-	idbp->d_off = pa->cook;
-	idbp->d_name[namelen] = '\0';
-	pa->done = 1;
-	memcpy(idbp->d_name, pa->name, namelen);
-	return 0;
-}
-
-/*
- * Getdents put routine for 64-bit ABI, uio form.
- */
-static int
-xfs_dir2_put_dirent64_uio(
-	xfs_dir2_put_args_t	*pa)
-{
-	xfs_dirent_t		*idbp;		/* dirent pointer */
-	int			namelen;	/* entry name length */
-	int			reclen;		/* entry total length */
-	int			rval;		/* return value */
-	uio_t			*uio;		/* I/O control */
-
-	namelen = pa->namelen;
-	reclen = DIRENTSIZE(namelen);
-	uio = pa->uio;
-	/*
-	 * Won't fit in the remaining space.
-	 */
-	if (reclen > uio->uio_resid) {
-		pa->done = 0;
-		return 0;
-	}
-	idbp = pa->dbp;
-	idbp->d_reclen = reclen;
-	idbp->d_ino = pa->ino;
-	idbp->d_off = pa->cook;
-	idbp->d_name[namelen] = '\0';
-	memcpy(idbp->d_name, pa->name, namelen);
-	rval = xfs_uio_read((caddr_t)idbp, reclen, uio);
-	pa->done = (rval == 0);
-	return rval;
-}
-
-/*
  * Remove the given block from the directory.
  * This routine is used for data and free blocks, leaf/node are done
  * by xfs_da_shrink_inode.