1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright (c) 2020-2022, Red Hat, Inc.
4 * All Rights Reserved.
5 */
6 #include "xfs.h"
7 #include "xfs_fs.h"
8 #include "xfs_shared.h"
9 #include "xfs_format.h"
10 #include "xfs_log_format.h"
11 #include "xfs_trans_resv.h"
12 #include "xfs_mount.h"
13 #include "xfs_inode.h"
14 #include "xfs_trans.h"
15 #include "xfs_trans_priv.h"
16 #include "xfs_ag.h"
17 #include "xfs_iunlink_item.h"
18 #include "xfs_trace.h"
19 #include "xfs_error.h"
20
21 struct kmem_cache *xfs_iunlink_cache;
22
IUL_ITEM(struct xfs_log_item * lip)23 static inline struct xfs_iunlink_item *IUL_ITEM(struct xfs_log_item *lip)
24 {
25 return container_of(lip, struct xfs_iunlink_item, item);
26 }
27
28 static void
xfs_iunlink_item_release(struct xfs_log_item * lip)29 xfs_iunlink_item_release(
30 struct xfs_log_item *lip)
31 {
32 struct xfs_iunlink_item *iup = IUL_ITEM(lip);
33
34 xfs_perag_put(iup->pag);
35 kmem_cache_free(xfs_iunlink_cache, IUL_ITEM(lip));
36 }
37
38
39 static uint64_t
xfs_iunlink_item_sort(struct xfs_log_item * lip)40 xfs_iunlink_item_sort(
41 struct xfs_log_item *lip)
42 {
43 return IUL_ITEM(lip)->ip->i_ino;
44 }
45
46 /*
47 * Look up the inode cluster buffer and log the on-disk unlinked inode change
48 * we need to make.
49 */
50 static int
xfs_iunlink_log_dinode(struct xfs_trans * tp,struct xfs_iunlink_item * iup)51 xfs_iunlink_log_dinode(
52 struct xfs_trans *tp,
53 struct xfs_iunlink_item *iup)
54 {
55 struct xfs_mount *mp = tp->t_mountp;
56 struct xfs_inode *ip = iup->ip;
57 struct xfs_dinode *dip;
58 struct xfs_buf *ibp;
59 int offset;
60 int error;
61
62 error = xfs_imap_to_bp(mp, tp, &ip->i_imap, &ibp);
63 if (error)
64 return error;
65 /*
66 * Don't log the unlinked field on stale buffers as this may be the
67 * transaction that frees the inode cluster and relogging the buffer
68 * here will incorrectly remove the stale state.
69 */
70 if (ibp->b_flags & XBF_STALE)
71 goto out;
72
73 dip = xfs_buf_offset(ibp, ip->i_imap.im_boffset);
74
75 /* Make sure the old pointer isn't garbage. */
76 if (be32_to_cpu(dip->di_next_unlinked) != iup->old_agino) {
77 xfs_inode_verifier_error(ip, -EFSCORRUPTED, __func__, dip,
78 sizeof(*dip), __this_address);
79 error = -EFSCORRUPTED;
80 goto out;
81 }
82
83 trace_xfs_iunlink_update_dinode(mp, iup->pag->pag_agno,
84 XFS_INO_TO_AGINO(mp, ip->i_ino),
85 be32_to_cpu(dip->di_next_unlinked), iup->next_agino);
86
87 dip->di_next_unlinked = cpu_to_be32(iup->next_agino);
88 offset = ip->i_imap.im_boffset +
89 offsetof(struct xfs_dinode, di_next_unlinked);
90
91 xfs_dinode_calc_crc(mp, dip);
92 xfs_trans_inode_buf(tp, ibp);
93 xfs_trans_log_buf(tp, ibp, offset, offset + sizeof(xfs_agino_t) - 1);
94 return 0;
95 out:
96 xfs_trans_brelse(tp, ibp);
97 return error;
98 }
99
100 /*
101 * On precommit, we grab the inode cluster buffer for the inode number we were
102 * passed, then update the next unlinked field for that inode in the buffer and
103 * log the buffer. This ensures that the inode cluster buffer was logged in the
104 * correct order w.r.t. other inode cluster buffers. We can then remove the
105 * iunlink item from the transaction and release it as it is has now served it's
106 * purpose.
107 */
108 static int
xfs_iunlink_item_precommit(struct xfs_trans * tp,struct xfs_log_item * lip)109 xfs_iunlink_item_precommit(
110 struct xfs_trans *tp,
111 struct xfs_log_item *lip)
112 {
113 struct xfs_iunlink_item *iup = IUL_ITEM(lip);
114 int error;
115
116 error = xfs_iunlink_log_dinode(tp, iup);
117 list_del(&lip->li_trans);
118 xfs_iunlink_item_release(lip);
119 return error;
120 }
121
122 static const struct xfs_item_ops xfs_iunlink_item_ops = {
123 .iop_release = xfs_iunlink_item_release,
124 .iop_sort = xfs_iunlink_item_sort,
125 .iop_precommit = xfs_iunlink_item_precommit,
126 };
127
128
129 /*
130 * Initialize the inode log item for a newly allocated (in-core) inode.
131 *
132 * Inode extents can only reside within an AG. Hence specify the starting
133 * block for the inode chunk by offset within an AG as well as the
134 * length of the allocated extent.
135 *
136 * This joins the item to the transaction and marks it dirty so
137 * that we don't need a separate call to do this, nor does the
138 * caller need to know anything about the iunlink item.
139 */
140 int
xfs_iunlink_log_inode(struct xfs_trans * tp,struct xfs_inode * ip,struct xfs_perag * pag,xfs_agino_t next_agino)141 xfs_iunlink_log_inode(
142 struct xfs_trans *tp,
143 struct xfs_inode *ip,
144 struct xfs_perag *pag,
145 xfs_agino_t next_agino)
146 {
147 struct xfs_mount *mp = tp->t_mountp;
148 struct xfs_iunlink_item *iup;
149
150 ASSERT(xfs_verify_agino_or_null(pag, next_agino));
151 ASSERT(xfs_verify_agino_or_null(pag, ip->i_next_unlinked));
152
153 /*
154 * Since we're updating a linked list, we should never find that the
155 * current pointer is the same as the new value, unless we're
156 * terminating the list.
157 */
158 if (ip->i_next_unlinked == next_agino) {
159 if (next_agino != NULLAGINO)
160 return -EFSCORRUPTED;
161 return 0;
162 }
163
164 iup = kmem_cache_zalloc(xfs_iunlink_cache, GFP_KERNEL | __GFP_NOFAIL);
165 xfs_log_item_init(mp, &iup->item, XFS_LI_IUNLINK,
166 &xfs_iunlink_item_ops);
167
168 iup->ip = ip;
169 iup->next_agino = next_agino;
170 iup->old_agino = ip->i_next_unlinked;
171 iup->pag = xfs_perag_hold(pag);
172
173 xfs_trans_add_item(tp, &iup->item);
174 tp->t_flags |= XFS_TRANS_DIRTY;
175 set_bit(XFS_LI_DIRTY, &iup->item.li_flags);
176 return 0;
177 }
178
179