summaryrefslogtreecommitdiffstats
path: root/fs/xfs/xfs_iunlink_item.c
blob: 43005ce8bd48a1f3c11193ba9a2a09ffed40f6e0 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright (c) 2020-2022, Red Hat, Inc.
 * All Rights Reserved.
 */
#include "xfs.h"
#include "xfs_fs.h"
#include "xfs_shared.h"
#include "xfs_format.h"
#include "xfs_log_format.h"
#include "xfs_trans_resv.h"
#include "xfs_mount.h"
#include "xfs_inode.h"
#include "xfs_trans.h"
#include "xfs_trans_priv.h"
#include "xfs_ag.h"
#include "xfs_iunlink_item.h"
#include "xfs_trace.h"
#include "xfs_error.h"

struct kmem_cache	*xfs_iunlink_cache;

static inline struct xfs_iunlink_item *IUL_ITEM(struct xfs_log_item *lip)
{
	return container_of(lip, struct xfs_iunlink_item, item);
}

static void
xfs_iunlink_item_release(
	struct xfs_log_item	*lip)
{
	struct xfs_iunlink_item	*iup = IUL_ITEM(lip);

	xfs_perag_put(iup->pag);
	kmem_cache_free(xfs_iunlink_cache, IUL_ITEM(lip));
}


static uint64_t
xfs_iunlink_item_sort(
	struct xfs_log_item	*lip)
{
	return IUL_ITEM(lip)->ip->i_ino;
}

/*
 * Look up the inode cluster buffer and log the on-disk unlinked inode change
 * we need to make.
 */
static int
xfs_iunlink_log_dinode(
	struct xfs_trans	*tp,
	struct xfs_iunlink_item	*iup)
{
	struct xfs_mount	*mp = tp->t_mountp;
	struct xfs_inode	*ip = iup->ip;
	struct xfs_dinode	*dip;
	struct xfs_buf		*ibp;
	int			offset;
	int			error;

	error = xfs_imap_to_bp(mp, tp, &ip->i_imap, &ibp);
	if (error)
		return error;
	/*
	 * Don't log the unlinked field on stale buffers as this may be the
	 * transaction that frees the inode cluster and relogging the buffer
	 * here will incorrectly remove the stale state.
	 */
	if (ibp->b_flags & XBF_STALE)
		goto out;

	dip = xfs_buf_offset(ibp, ip->i_imap.im_boffset);

	/* Make sure the old pointer isn't garbage. */
	if (be32_to_cpu(dip->di_next_unlinked) != iup->old_agino) {
		xfs_inode_verifier_error(ip, -EFSCORRUPTED, __func__, dip,
				sizeof(*dip), __this_address);
		error = -EFSCORRUPTED;
		goto out;
	}

	trace_xfs_iunlink_update_dinode(mp, iup->pag->pag_agno,
			XFS_INO_TO_AGINO(mp, ip->i_ino),
			be32_to_cpu(dip->di_next_unlinked), iup->next_agino);

	dip->di_next_unlinked = cpu_to_be32(iup->next_agino);
	offset = ip->i_imap.im_boffset +
			offsetof(struct xfs_dinode, di_next_unlinked);

	xfs_dinode_calc_crc(mp, dip);
	xfs_trans_inode_buf(tp, ibp);
	xfs_trans_log_buf(tp, ibp, offset, offset + sizeof(xfs_agino_t) - 1);
	return 0;
out:
	xfs_trans_brelse(tp, ibp);
	return error;
}

/*
 * On precommit, we grab the inode cluster buffer for the inode number we were
 * passed, then update the next unlinked field for that inode in the buffer and
 * log the buffer. This ensures that the inode cluster buffer was logged in the
 * correct order w.r.t. other inode cluster buffers. We can then remove the
 * iunlink item from the transaction and release it as it is has now served it's
 * purpose.
 */
static int
xfs_iunlink_item_precommit(
	struct xfs_trans	*tp,
	struct xfs_log_item	*lip)
{
	struct xfs_iunlink_item	*iup = IUL_ITEM(lip);
	int			error;

	error = xfs_iunlink_log_dinode(tp, iup);
	list_del(&lip->li_trans);
	xfs_iunlink_item_release(lip);
	return error;
}

static const struct xfs_item_ops xfs_iunlink_item_ops = {
	.iop_release	= xfs_iunlink_item_release,
	.iop_sort	= xfs_iunlink_item_sort,
	.iop_precommit	= xfs_iunlink_item_precommit,
};


/*
 * Initialize the inode log item for a newly allocated (in-core) inode.
 *
 * Inode extents can only reside within an AG. Hence specify the starting
 * block for the inode chunk by offset within an AG as well as the
 * length of the allocated extent.
 *
 * This joins the item to the transaction and marks it dirty so
 * that we don't need a separate call to do this, nor does the
 * caller need to know anything about the iunlink item.
 */
int
xfs_iunlink_log_inode(
	struct xfs_trans	*tp,
	struct xfs_inode	*ip,
	struct xfs_perag	*pag,
	xfs_agino_t		next_agino)
{
	struct xfs_mount	*mp = tp->t_mountp;
	struct xfs_iunlink_item	*iup;

	ASSERT(xfs_verify_agino_or_null(pag, next_agino));
	ASSERT(xfs_verify_agino_or_null(pag, ip->i_next_unlinked));

	/*
	 * Since we're updating a linked list, we should never find that the
	 * current pointer is the same as the new value, unless we're
	 * terminating the list.
	 */
	if (ip->i_next_unlinked == next_agino) {
		if (next_agino != NULLAGINO)
			return -EFSCORRUPTED;
		return 0;
	}

	iup = kmem_cache_zalloc(xfs_iunlink_cache, GFP_KERNEL | __GFP_NOFAIL);
	xfs_log_item_init(mp, &iup->item, XFS_LI_IUNLINK,
			  &xfs_iunlink_item_ops);

	iup->ip = ip;
	iup->next_agino = next_agino;
	iup->old_agino = ip->i_next_unlinked;

	atomic_inc(&pag->pag_ref);
	iup->pag = pag;

	xfs_trans_add_item(tp, &iup->item);
	tp->t_flags |= XFS_TRANS_DIRTY;
	set_bit(XFS_LI_DIRTY, &iup->item.li_flags);
	return 0;
}