summaryrefslogtreecommitdiffstats
path: root/fs/xfs/linux-2.6/xfs_export.c
diff options
context:
space:
mode:
Diffstat (limited to 'fs/xfs/linux-2.6/xfs_export.c')
-rw-r--r--fs/xfs/linux-2.6/xfs_export.c205
1 files changed, 205 insertions, 0 deletions
diff --git a/fs/xfs/linux-2.6/xfs_export.c b/fs/xfs/linux-2.6/xfs_export.c
new file mode 100644
index 000000000000..f372a1a5e168
--- /dev/null
+++ b/fs/xfs/linux-2.6/xfs_export.c
@@ -0,0 +1,205 @@
+/*
+ * Copyright (c) 2004-2005 Silicon Graphics, Inc. All Rights Reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it would be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ *
+ * Further, this software is distributed without any warranty that it is
+ * free of the rightful claim of any third person regarding infringement
+ * or the like. Any license provided herein, whether implied or
+ * otherwise, applies only to this software file. Patent licenses, if
+ * any, provided herein do not apply to combinations of this program with
+ * other software, or any other product whatsoever.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write the Free Software Foundation, Inc., 59
+ * Temple Place - Suite 330, Boston MA 02111-1307, USA.
+ *
+ * Contact information: Silicon Graphics, Inc., 1600 Amphitheatre Pkwy,
+ * Mountain View, CA 94043, or:
+ *
+ * http://www.sgi.com
+ *
+ * For further information regarding this notice, see:
+ *
+ * http://oss.sgi.com/projects/GenInfo/SGIGPLNoticeExplan/
+ */
+
+#include "xfs.h"
+#include "xfs_types.h"
+#include "xfs_dmapi.h"
+#include "xfs_log.h"
+#include "xfs_trans.h"
+#include "xfs_sb.h"
+#include "xfs_dir.h"
+#include "xfs_mount.h"
+#include "xfs_export.h"
+
+/*
+ * XFS encode and decodes the fileid portion of NFS filehandles
+ * itself instead of letting the generic NFS code do it. This
+ * allows filesystems with 64 bit inode numbers to be exported.
+ *
+ * Note that a side effect is that xfs_vget() won't be passed a
+ * zero inode/generation pair under normal circumstances. As
+ * however a malicious client could send us such data, the check
+ * remains in that code.
+ */
+
+
+STATIC struct dentry *
+linvfs_decode_fh(
+ struct super_block *sb,
+ __u32 *fh,
+ int fh_len,
+ int fileid_type,
+ int (*acceptable)(
+ void *context,
+ struct dentry *de),
+ void *context)
+{
+ xfs_fid2_t ifid;
+ xfs_fid2_t pfid;
+ void *parent = NULL;
+ int is64 = 0;
+ __u32 *p = fh;
+
+#if XFS_BIG_INUMS
+ is64 = (fileid_type & XFS_FILEID_TYPE_64FLAG);
+ fileid_type &= ~XFS_FILEID_TYPE_64FLAG;
+#endif
+
+ /*
+ * Note that we only accept fileids which are long enough
+ * rather than allow the parent generation number to default
+ * to zero. XFS considers zero a valid generation number not
+ * an invalid/wildcard value. There's little point printk'ing
+ * a warning here as we don't have the client information
+ * which would make such a warning useful.
+ */
+ if (fileid_type > 2 ||
+ fh_len < xfs_fileid_length((fileid_type == 2), is64))
+ return NULL;
+
+ p = xfs_fileid_decode_fid2(p, &ifid, is64);
+
+ if (fileid_type == 2) {
+ p = xfs_fileid_decode_fid2(p, &pfid, is64);
+ parent = &pfid;
+ }
+
+ fh = (__u32 *)&ifid;
+ return find_exported_dentry(sb, fh, parent, acceptable, context);
+}
+
+
+STATIC int
+linvfs_encode_fh(
+ struct dentry *dentry,
+ __u32 *fh,
+ int *max_len,
+ int connectable)
+{
+ struct inode *inode = dentry->d_inode;
+ int type = 1;
+ __u32 *p = fh;
+ int len;
+ int is64 = 0;
+#if XFS_BIG_INUMS
+ vfs_t *vfs = LINVFS_GET_VFS(inode->i_sb);
+ xfs_mount_t *mp = XFS_VFSTOM(vfs);
+
+ if (!(mp->m_flags & XFS_MOUNT_32BITINOOPT)) {
+ /* filesystem may contain 64bit inode numbers */
+ is64 = XFS_FILEID_TYPE_64FLAG;
+ }
+#endif
+
+ /* Directories don't need their parent encoded, they have ".." */
+ if (S_ISDIR(inode->i_mode))
+ connectable = 0;
+
+ /*
+ * Only encode if there is enough space given. In practice
+ * this means we can't export a filesystem with 64bit inodes
+ * over NFSv2 with the subtree_check export option; the other
+ * seven combinations work. The real answer is "don't use v2".
+ */
+ len = xfs_fileid_length(connectable, is64);
+ if (*max_len < len)
+ return 255;
+ *max_len = len;
+
+ p = xfs_fileid_encode_inode(p, inode, is64);
+ if (connectable) {
+ spin_lock(&dentry->d_lock);
+ p = xfs_fileid_encode_inode(p, dentry->d_parent->d_inode, is64);
+ spin_unlock(&dentry->d_lock);
+ type = 2;
+ }
+ BUG_ON((p - fh) != len);
+ return type | is64;
+}
+
+STATIC struct dentry *
+linvfs_get_dentry(
+ struct super_block *sb,
+ void *data)
+{
+ vnode_t *vp;
+ struct inode *inode;
+ struct dentry *result;
+ vfs_t *vfsp = LINVFS_GET_VFS(sb);
+ int error;
+
+ VFS_VGET(vfsp, &vp, (fid_t *)data, error);
+ if (error || vp == NULL)
+ return ERR_PTR(-ESTALE) ;
+
+ inode = LINVFS_GET_IP(vp);
+ result = d_alloc_anon(inode);
+ if (!result) {
+ iput(inode);
+ return ERR_PTR(-ENOMEM);
+ }
+ return result;
+}
+
+STATIC struct dentry *
+linvfs_get_parent(
+ struct dentry *child)
+{
+ int error;
+ vnode_t *vp, *cvp;
+ struct dentry *parent;
+ struct dentry dotdot;
+
+ dotdot.d_name.name = "..";
+ dotdot.d_name.len = 2;
+ dotdot.d_inode = NULL;
+
+ cvp = NULL;
+ vp = LINVFS_GET_VP(child->d_inode);
+ VOP_LOOKUP(vp, &dotdot, &cvp, 0, NULL, NULL, error);
+ if (unlikely(error))
+ return ERR_PTR(-error);
+
+ parent = d_alloc_anon(LINVFS_GET_IP(cvp));
+ if (unlikely(!parent)) {
+ VN_RELE(cvp);
+ return ERR_PTR(-ENOMEM);
+ }
+ return parent;
+}
+
+struct export_operations linvfs_export_ops = {
+ .decode_fh = linvfs_decode_fh,
+ .encode_fh = linvfs_encode_fh,
+ .get_parent = linvfs_get_parent,
+ .get_dentry = linvfs_get_dentry,
+};