10b61f8a4SDave Chinner // SPDX-License-Identifier: GPL-2.0
2c59d87c4SChristoph Hellwig /*
3c59d87c4SChristoph Hellwig * Copyright (c) 2004-2005 Silicon Graphics, Inc.
4c59d87c4SChristoph Hellwig * All Rights Reserved.
5c59d87c4SChristoph Hellwig */
6c59d87c4SChristoph Hellwig #include "xfs.h"
75467b34bSDarrick J. Wong #include "xfs_shared.h"
8a4fbe6abSDave Chinner #include "xfs_format.h"
9239880efSDave Chinner #include "xfs_log_format.h"
10239880efSDave Chinner #include "xfs_trans_resv.h"
11c59d87c4SChristoph Hellwig #include "xfs_mount.h"
122b9ab5abSDave Chinner #include "xfs_dir2.h"
13c59d87c4SChristoph Hellwig #include "xfs_export.h"
14c59d87c4SChristoph Hellwig #include "xfs_inode.h"
15239880efSDave Chinner #include "xfs_trans.h"
16c59d87c4SChristoph Hellwig #include "xfs_inode_item.h"
1733479e05SDave Chinner #include "xfs_icache.h"
1852785112SChristoph Hellwig #include "xfs_pnfs.h"
19c59d87c4SChristoph Hellwig
20c59d87c4SChristoph Hellwig /*
21c59d87c4SChristoph Hellwig * Note that we only accept fileids which are long enough rather than allow
22c59d87c4SChristoph Hellwig * the parent generation number to default to zero. XFS considers zero a
23c59d87c4SChristoph Hellwig * valid generation number not an invalid/wildcard value.
24c59d87c4SChristoph Hellwig */
xfs_fileid_length(int fileid_type)25c59d87c4SChristoph Hellwig static int xfs_fileid_length(int fileid_type)
26c59d87c4SChristoph Hellwig {
27c59d87c4SChristoph Hellwig switch (fileid_type) {
28c59d87c4SChristoph Hellwig case FILEID_INO32_GEN:
29c59d87c4SChristoph Hellwig return 2;
30c59d87c4SChristoph Hellwig case FILEID_INO32_GEN_PARENT:
31c59d87c4SChristoph Hellwig return 4;
32c59d87c4SChristoph Hellwig case FILEID_INO32_GEN | XFS_FILEID_TYPE_64FLAG:
33c59d87c4SChristoph Hellwig return 3;
34c59d87c4SChristoph Hellwig case FILEID_INO32_GEN_PARENT | XFS_FILEID_TYPE_64FLAG:
35c59d87c4SChristoph Hellwig return 6;
36c59d87c4SChristoph Hellwig }
3794e07a75SNamjae Jeon return FILEID_INVALID;
38c59d87c4SChristoph Hellwig }
39c59d87c4SChristoph Hellwig
40c59d87c4SChristoph Hellwig STATIC int
xfs_fs_encode_fh(struct inode * inode,__u32 * fh,int * max_len,struct inode * parent)41c59d87c4SChristoph Hellwig xfs_fs_encode_fh(
42b0b0382bSAl Viro struct inode *inode,
43c59d87c4SChristoph Hellwig __u32 *fh,
44c59d87c4SChristoph Hellwig int *max_len,
45b0b0382bSAl Viro struct inode *parent)
46c59d87c4SChristoph Hellwig {
472e973b2cSDave Chinner struct xfs_mount *mp = XFS_M(inode->i_sb);
48c59d87c4SChristoph Hellwig struct fid *fid = (struct fid *)fh;
49c59d87c4SChristoph Hellwig struct xfs_fid64 *fid64 = (struct xfs_fid64 *)fh;
50c59d87c4SChristoph Hellwig int fileid_type;
51c59d87c4SChristoph Hellwig int len;
52c59d87c4SChristoph Hellwig
53c59d87c4SChristoph Hellwig /* Directories don't need their parent encoded, they have ".." */
54b0b0382bSAl Viro if (!parent)
55c59d87c4SChristoph Hellwig fileid_type = FILEID_INO32_GEN;
56c59d87c4SChristoph Hellwig else
57c59d87c4SChristoph Hellwig fileid_type = FILEID_INO32_GEN_PARENT;
58c59d87c4SChristoph Hellwig
59c59d87c4SChristoph Hellwig /*
60b63da6c8SRandy Dunlap * If the filesystem may contain 64bit inode numbers, we need
61c59d87c4SChristoph Hellwig * to use larger file handles that can represent them.
62c59d87c4SChristoph Hellwig *
63c59d87c4SChristoph Hellwig * While we only allocate inodes that do not fit into 32 bits any
64c59d87c4SChristoph Hellwig * large enough filesystem may contain them, thus the slightly
65c59d87c4SChristoph Hellwig * confusing looking conditional below.
66c59d87c4SChristoph Hellwig */
672e973b2cSDave Chinner if (!xfs_has_small_inums(mp) || xfs_is_inode32(mp))
68c59d87c4SChristoph Hellwig fileid_type |= XFS_FILEID_TYPE_64FLAG;
69c59d87c4SChristoph Hellwig
70c59d87c4SChristoph Hellwig /*
71c59d87c4SChristoph Hellwig * Only encode if there is enough space given. In practice
72c59d87c4SChristoph Hellwig * this means we can't export a filesystem with 64bit inodes
73c59d87c4SChristoph Hellwig * over NFSv2 with the subtree_check export option; the other
74c59d87c4SChristoph Hellwig * seven combinations work. The real answer is "don't use v2".
75c59d87c4SChristoph Hellwig */
76c59d87c4SChristoph Hellwig len = xfs_fileid_length(fileid_type);
77c59d87c4SChristoph Hellwig if (*max_len < len) {
78c59d87c4SChristoph Hellwig *max_len = len;
7994e07a75SNamjae Jeon return FILEID_INVALID;
80c59d87c4SChristoph Hellwig }
81c59d87c4SChristoph Hellwig *max_len = len;
82c59d87c4SChristoph Hellwig
83c59d87c4SChristoph Hellwig switch (fileid_type) {
84c59d87c4SChristoph Hellwig case FILEID_INO32_GEN_PARENT:
85b0b0382bSAl Viro fid->i32.parent_ino = XFS_I(parent)->i_ino;
86b0b0382bSAl Viro fid->i32.parent_gen = parent->i_generation;
8753004ee7SGustavo A. R. Silva fallthrough;
88c59d87c4SChristoph Hellwig case FILEID_INO32_GEN:
89c29f7d45SChristoph Hellwig fid->i32.ino = XFS_I(inode)->i_ino;
90c59d87c4SChristoph Hellwig fid->i32.gen = inode->i_generation;
91c59d87c4SChristoph Hellwig break;
92c59d87c4SChristoph Hellwig case FILEID_INO32_GEN_PARENT | XFS_FILEID_TYPE_64FLAG:
93b0b0382bSAl Viro fid64->parent_ino = XFS_I(parent)->i_ino;
94b0b0382bSAl Viro fid64->parent_gen = parent->i_generation;
9553004ee7SGustavo A. R. Silva fallthrough;
96c59d87c4SChristoph Hellwig case FILEID_INO32_GEN | XFS_FILEID_TYPE_64FLAG:
97c29f7d45SChristoph Hellwig fid64->ino = XFS_I(inode)->i_ino;
98c59d87c4SChristoph Hellwig fid64->gen = inode->i_generation;
99c59d87c4SChristoph Hellwig break;
100c59d87c4SChristoph Hellwig }
101c59d87c4SChristoph Hellwig
102c59d87c4SChristoph Hellwig return fileid_type;
103c59d87c4SChristoph Hellwig }
104c59d87c4SChristoph Hellwig
105c59d87c4SChristoph Hellwig STATIC struct inode *
xfs_nfs_get_inode(struct super_block * sb,u64 ino,u32 generation)106c59d87c4SChristoph Hellwig xfs_nfs_get_inode(
107c59d87c4SChristoph Hellwig struct super_block *sb,
108c59d87c4SChristoph Hellwig u64 ino,
109c59d87c4SChristoph Hellwig u32 generation)
110c59d87c4SChristoph Hellwig {
111c59d87c4SChristoph Hellwig xfs_mount_t *mp = XFS_M(sb);
112c59d87c4SChristoph Hellwig xfs_inode_t *ip;
113c59d87c4SChristoph Hellwig int error;
114c59d87c4SChristoph Hellwig
115c59d87c4SChristoph Hellwig /*
116c59d87c4SChristoph Hellwig * NFS can sometimes send requests for ino 0. Fail them gracefully.
117c59d87c4SChristoph Hellwig */
118c59d87c4SChristoph Hellwig if (ino == 0)
119c59d87c4SChristoph Hellwig return ERR_PTR(-ESTALE);
120c59d87c4SChristoph Hellwig
121c59d87c4SChristoph Hellwig /*
122c59d87c4SChristoph Hellwig * The XFS_IGET_UNTRUSTED means that an invalid inode number is just
123c59d87c4SChristoph Hellwig * fine and not an indication of a corrupted filesystem as clients can
124c59d87c4SChristoph Hellwig * send invalid file handles and we have to handle it gracefully..
125c59d87c4SChristoph Hellwig */
126c59d87c4SChristoph Hellwig error = xfs_iget(mp, NULL, ino, XFS_IGET_UNTRUSTED, 0, &ip);
127c59d87c4SChristoph Hellwig if (error) {
12829cad0b3SDave Chinner
129c59d87c4SChristoph Hellwig /*
130c59d87c4SChristoph Hellwig * EINVAL means the inode cluster doesn't exist anymore.
13129cad0b3SDave Chinner * EFSCORRUPTED means the metadata pointing to the inode cluster
13229cad0b3SDave Chinner * or the inode cluster itself is corrupt. This implies the
13329cad0b3SDave Chinner * filehandle is stale, so we should translate it here.
134c59d87c4SChristoph Hellwig * We don't use ESTALE directly down the chain to not
135c59d87c4SChristoph Hellwig * confuse applications using bulkstat that expect EINVAL.
136c59d87c4SChristoph Hellwig */
13729cad0b3SDave Chinner switch (error) {
13829cad0b3SDave Chinner case -EINVAL:
13929cad0b3SDave Chinner case -ENOENT:
14029cad0b3SDave Chinner case -EFSCORRUPTED:
1412451337dSDave Chinner error = -ESTALE;
14229cad0b3SDave Chinner break;
14329cad0b3SDave Chinner default:
14429cad0b3SDave Chinner break;
14529cad0b3SDave Chinner }
1462451337dSDave Chinner return ERR_PTR(error);
147c59d87c4SChristoph Hellwig }
148c59d87c4SChristoph Hellwig
149*537c013bSDarrick J. Wong /*
150*537c013bSDarrick J. Wong * Reload the incore unlinked list to avoid failure in inodegc.
151*537c013bSDarrick J. Wong * Use an unlocked check here because unrecovered unlinked inodes
152*537c013bSDarrick J. Wong * should be somewhat rare.
153*537c013bSDarrick J. Wong */
154*537c013bSDarrick J. Wong if (xfs_inode_unlinked_incomplete(ip)) {
15583771c50SDarrick J. Wong error = xfs_inode_reload_unlinked(ip);
15683771c50SDarrick J. Wong if (error) {
157*537c013bSDarrick J. Wong xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
15883771c50SDarrick J. Wong xfs_irele(ip);
15983771c50SDarrick J. Wong return ERR_PTR(error);
16083771c50SDarrick J. Wong }
161*537c013bSDarrick J. Wong }
16283771c50SDarrick J. Wong
1639e9a2674SDave Chinner if (VFS_I(ip)->i_generation != generation) {
16444a8736bSDarrick J. Wong xfs_irele(ip);
165c59d87c4SChristoph Hellwig return ERR_PTR(-ESTALE);
166c59d87c4SChristoph Hellwig }
167c59d87c4SChristoph Hellwig
168c59d87c4SChristoph Hellwig return VFS_I(ip);
169c59d87c4SChristoph Hellwig }
170c59d87c4SChristoph Hellwig
171c59d87c4SChristoph Hellwig STATIC struct dentry *
xfs_fs_fh_to_dentry(struct super_block * sb,struct fid * fid,int fh_len,int fileid_type)172c59d87c4SChristoph Hellwig xfs_fs_fh_to_dentry(struct super_block *sb, struct fid *fid,
173c59d87c4SChristoph Hellwig int fh_len, int fileid_type)
174c59d87c4SChristoph Hellwig {
175c59d87c4SChristoph Hellwig struct xfs_fid64 *fid64 = (struct xfs_fid64 *)fid;
176c59d87c4SChristoph Hellwig struct inode *inode = NULL;
177c59d87c4SChristoph Hellwig
178c59d87c4SChristoph Hellwig if (fh_len < xfs_fileid_length(fileid_type))
179c59d87c4SChristoph Hellwig return NULL;
180c59d87c4SChristoph Hellwig
181c59d87c4SChristoph Hellwig switch (fileid_type) {
182c59d87c4SChristoph Hellwig case FILEID_INO32_GEN_PARENT:
183c59d87c4SChristoph Hellwig case FILEID_INO32_GEN:
184c59d87c4SChristoph Hellwig inode = xfs_nfs_get_inode(sb, fid->i32.ino, fid->i32.gen);
185c59d87c4SChristoph Hellwig break;
186c59d87c4SChristoph Hellwig case FILEID_INO32_GEN_PARENT | XFS_FILEID_TYPE_64FLAG:
187c59d87c4SChristoph Hellwig case FILEID_INO32_GEN | XFS_FILEID_TYPE_64FLAG:
188c59d87c4SChristoph Hellwig inode = xfs_nfs_get_inode(sb, fid64->ino, fid64->gen);
189c59d87c4SChristoph Hellwig break;
190c59d87c4SChristoph Hellwig }
191c59d87c4SChristoph Hellwig
192c59d87c4SChristoph Hellwig return d_obtain_alias(inode);
193c59d87c4SChristoph Hellwig }
194c59d87c4SChristoph Hellwig
195c59d87c4SChristoph Hellwig STATIC struct dentry *
xfs_fs_fh_to_parent(struct super_block * sb,struct fid * fid,int fh_len,int fileid_type)196c59d87c4SChristoph Hellwig xfs_fs_fh_to_parent(struct super_block *sb, struct fid *fid,
197c59d87c4SChristoph Hellwig int fh_len, int fileid_type)
198c59d87c4SChristoph Hellwig {
199c59d87c4SChristoph Hellwig struct xfs_fid64 *fid64 = (struct xfs_fid64 *)fid;
200c59d87c4SChristoph Hellwig struct inode *inode = NULL;
201c59d87c4SChristoph Hellwig
20235c2a7f4SHugh Dickins if (fh_len < xfs_fileid_length(fileid_type))
20335c2a7f4SHugh Dickins return NULL;
20435c2a7f4SHugh Dickins
205c59d87c4SChristoph Hellwig switch (fileid_type) {
206c59d87c4SChristoph Hellwig case FILEID_INO32_GEN_PARENT:
207c59d87c4SChristoph Hellwig inode = xfs_nfs_get_inode(sb, fid->i32.parent_ino,
208c59d87c4SChristoph Hellwig fid->i32.parent_gen);
209c59d87c4SChristoph Hellwig break;
210c59d87c4SChristoph Hellwig case FILEID_INO32_GEN_PARENT | XFS_FILEID_TYPE_64FLAG:
211c59d87c4SChristoph Hellwig inode = xfs_nfs_get_inode(sb, fid64->parent_ino,
212c59d87c4SChristoph Hellwig fid64->parent_gen);
213c59d87c4SChristoph Hellwig break;
214c59d87c4SChristoph Hellwig }
215c59d87c4SChristoph Hellwig
216c59d87c4SChristoph Hellwig return d_obtain_alias(inode);
217c59d87c4SChristoph Hellwig }
218c59d87c4SChristoph Hellwig
219c59d87c4SChristoph Hellwig STATIC struct dentry *
xfs_fs_get_parent(struct dentry * child)220c59d87c4SChristoph Hellwig xfs_fs_get_parent(
221c59d87c4SChristoph Hellwig struct dentry *child)
222c59d87c4SChristoph Hellwig {
223c59d87c4SChristoph Hellwig int error;
224c59d87c4SChristoph Hellwig struct xfs_inode *cip;
225c59d87c4SChristoph Hellwig
2262b0143b5SDavid Howells error = xfs_lookup(XFS_I(d_inode(child)), &xfs_name_dotdot, &cip, NULL);
227c59d87c4SChristoph Hellwig if (unlikely(error))
2282451337dSDave Chinner return ERR_PTR(error);
229c59d87c4SChristoph Hellwig
230c59d87c4SChristoph Hellwig return d_obtain_alias(VFS_I(cip));
231c59d87c4SChristoph Hellwig }
232c59d87c4SChristoph Hellwig
233c59d87c4SChristoph Hellwig STATIC int
xfs_fs_nfs_commit_metadata(struct inode * inode)234c59d87c4SChristoph Hellwig xfs_fs_nfs_commit_metadata(
235c59d87c4SChristoph Hellwig struct inode *inode)
236c59d87c4SChristoph Hellwig {
23754fbdd10SChristoph Hellwig return xfs_log_force_inode(XFS_I(inode));
238c59d87c4SChristoph Hellwig }
239c59d87c4SChristoph Hellwig
240c59d87c4SChristoph Hellwig const struct export_operations xfs_export_operations = {
241c59d87c4SChristoph Hellwig .encode_fh = xfs_fs_encode_fh,
242c59d87c4SChristoph Hellwig .fh_to_dentry = xfs_fs_fh_to_dentry,
243c59d87c4SChristoph Hellwig .fh_to_parent = xfs_fs_fh_to_parent,
244c59d87c4SChristoph Hellwig .get_parent = xfs_fs_get_parent,
245c59d87c4SChristoph Hellwig .commit_metadata = xfs_fs_nfs_commit_metadata,
24615d66ac2SBenjamin Coddington #ifdef CONFIG_EXPORTFS_BLOCK_OPS
24752785112SChristoph Hellwig .get_uuid = xfs_fs_get_uuid,
24852785112SChristoph Hellwig .map_blocks = xfs_fs_map_blocks,
24952785112SChristoph Hellwig .commit_blocks = xfs_fs_commit_blocks,
25052785112SChristoph Hellwig #endif
251c59d87c4SChristoph Hellwig };
252