xref: /openbmc/linux/fs/xfs/xfs_notify_failure.c (revision 7effbd18)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2022 Fujitsu.  All Rights Reserved.
4  */
5 
6 #include "xfs.h"
7 #include "xfs_shared.h"
8 #include "xfs_format.h"
9 #include "xfs_log_format.h"
10 #include "xfs_trans_resv.h"
11 #include "xfs_mount.h"
12 #include "xfs_alloc.h"
13 #include "xfs_bit.h"
14 #include "xfs_btree.h"
15 #include "xfs_inode.h"
16 #include "xfs_icache.h"
17 #include "xfs_rmap.h"
18 #include "xfs_rmap_btree.h"
19 #include "xfs_rtalloc.h"
20 #include "xfs_trans.h"
21 #include "xfs_ag.h"
22 
23 #include <linux/mm.h>
24 #include <linux/dax.h>
25 
26 struct xfs_failure_info {
27 	xfs_agblock_t		startblock;
28 	xfs_extlen_t		blockcount;
29 	int			mf_flags;
30 	bool			want_shutdown;
31 };
32 
33 static pgoff_t
34 xfs_failure_pgoff(
35 	struct xfs_mount		*mp,
36 	const struct xfs_rmap_irec	*rec,
37 	const struct xfs_failure_info	*notify)
38 {
39 	loff_t				pos = XFS_FSB_TO_B(mp, rec->rm_offset);
40 
41 	if (notify->startblock > rec->rm_startblock)
42 		pos += XFS_FSB_TO_B(mp,
43 				notify->startblock - rec->rm_startblock);
44 	return pos >> PAGE_SHIFT;
45 }
46 
47 static unsigned long
48 xfs_failure_pgcnt(
49 	struct xfs_mount		*mp,
50 	const struct xfs_rmap_irec	*rec,
51 	const struct xfs_failure_info	*notify)
52 {
53 	xfs_agblock_t			end_rec;
54 	xfs_agblock_t			end_notify;
55 	xfs_agblock_t			start_cross;
56 	xfs_agblock_t			end_cross;
57 
58 	start_cross = max(rec->rm_startblock, notify->startblock);
59 
60 	end_rec = rec->rm_startblock + rec->rm_blockcount;
61 	end_notify = notify->startblock + notify->blockcount;
62 	end_cross = min(end_rec, end_notify);
63 
64 	return XFS_FSB_TO_B(mp, end_cross - start_cross) >> PAGE_SHIFT;
65 }
66 
67 static int
68 xfs_dax_failure_fn(
69 	struct xfs_btree_cur		*cur,
70 	const struct xfs_rmap_irec	*rec,
71 	void				*data)
72 {
73 	struct xfs_mount		*mp = cur->bc_mp;
74 	struct xfs_inode		*ip;
75 	struct xfs_failure_info		*notify = data;
76 	int				error = 0;
77 
78 	if (XFS_RMAP_NON_INODE_OWNER(rec->rm_owner) ||
79 	    (rec->rm_flags & (XFS_RMAP_ATTR_FORK | XFS_RMAP_BMBT_BLOCK))) {
80 		notify->want_shutdown = true;
81 		return 0;
82 	}
83 
84 	/* Get files that incore, filter out others that are not in use. */
85 	error = xfs_iget(mp, cur->bc_tp, rec->rm_owner, XFS_IGET_INCORE,
86 			 0, &ip);
87 	/* Continue the rmap query if the inode isn't incore */
88 	if (error == -ENODATA)
89 		return 0;
90 	if (error) {
91 		notify->want_shutdown = true;
92 		return 0;
93 	}
94 
95 	error = mf_dax_kill_procs(VFS_I(ip)->i_mapping,
96 				  xfs_failure_pgoff(mp, rec, notify),
97 				  xfs_failure_pgcnt(mp, rec, notify),
98 				  notify->mf_flags);
99 	xfs_irele(ip);
100 	return error;
101 }
102 
103 static int
104 xfs_dax_notify_ddev_failure(
105 	struct xfs_mount	*mp,
106 	xfs_daddr_t		daddr,
107 	xfs_daddr_t		bblen,
108 	int			mf_flags)
109 {
110 	struct xfs_failure_info	notify = { .mf_flags = mf_flags };
111 	struct xfs_trans	*tp = NULL;
112 	struct xfs_btree_cur	*cur = NULL;
113 	struct xfs_buf		*agf_bp = NULL;
114 	int			error = 0;
115 	xfs_fsblock_t		fsbno = XFS_DADDR_TO_FSB(mp, daddr);
116 	xfs_agnumber_t		agno = XFS_FSB_TO_AGNO(mp, fsbno);
117 	xfs_fsblock_t		end_fsbno = XFS_DADDR_TO_FSB(mp, daddr + bblen);
118 	xfs_agnumber_t		end_agno = XFS_FSB_TO_AGNO(mp, end_fsbno);
119 
120 	error = xfs_trans_alloc_empty(mp, &tp);
121 	if (error)
122 		return error;
123 
124 	for (; agno <= end_agno; agno++) {
125 		struct xfs_rmap_irec	ri_low = { };
126 		struct xfs_rmap_irec	ri_high;
127 		struct xfs_agf		*agf;
128 		xfs_agblock_t		agend;
129 		struct xfs_perag	*pag;
130 
131 		pag = xfs_perag_get(mp, agno);
132 		error = xfs_alloc_read_agf(pag, tp, 0, &agf_bp);
133 		if (error) {
134 			xfs_perag_put(pag);
135 			break;
136 		}
137 
138 		cur = xfs_rmapbt_init_cursor(mp, tp, agf_bp, pag);
139 
140 		/*
141 		 * Set the rmap range from ri_low to ri_high, which represents
142 		 * a [start, end] where we looking for the files or metadata.
143 		 */
144 		memset(&ri_high, 0xFF, sizeof(ri_high));
145 		ri_low.rm_startblock = XFS_FSB_TO_AGBNO(mp, fsbno);
146 		if (agno == end_agno)
147 			ri_high.rm_startblock = XFS_FSB_TO_AGBNO(mp, end_fsbno);
148 
149 		agf = agf_bp->b_addr;
150 		agend = min(be32_to_cpu(agf->agf_length),
151 				ri_high.rm_startblock);
152 		notify.startblock = ri_low.rm_startblock;
153 		notify.blockcount = agend - ri_low.rm_startblock;
154 
155 		error = xfs_rmap_query_range(cur, &ri_low, &ri_high,
156 				xfs_dax_failure_fn, &notify);
157 		xfs_btree_del_cursor(cur, error);
158 		xfs_trans_brelse(tp, agf_bp);
159 		xfs_perag_put(pag);
160 		if (error)
161 			break;
162 
163 		fsbno = XFS_AGB_TO_FSB(mp, agno + 1, 0);
164 	}
165 
166 	xfs_trans_cancel(tp);
167 	if (error || notify.want_shutdown) {
168 		xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_ONDISK);
169 		if (!error)
170 			error = -EFSCORRUPTED;
171 	}
172 	return error;
173 }
174 
175 static int
176 xfs_dax_notify_failure(
177 	struct dax_device	*dax_dev,
178 	u64			offset,
179 	u64			len,
180 	int			mf_flags)
181 {
182 	struct xfs_mount	*mp = dax_holder(dax_dev);
183 	u64			ddev_start;
184 	u64			ddev_end;
185 
186 	if (!(mp->m_super->s_flags & SB_BORN)) {
187 		xfs_warn(mp, "filesystem is not ready for notify_failure()!");
188 		return -EIO;
189 	}
190 
191 	if (mp->m_rtdev_targp && mp->m_rtdev_targp->bt_daxdev == dax_dev) {
192 		xfs_debug(mp,
193 			 "notify_failure() not supported on realtime device!");
194 		return -EOPNOTSUPP;
195 	}
196 
197 	if (mp->m_logdev_targp && mp->m_logdev_targp->bt_daxdev == dax_dev &&
198 	    mp->m_logdev_targp != mp->m_ddev_targp) {
199 		xfs_err(mp, "ondisk log corrupt, shutting down fs!");
200 		xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_ONDISK);
201 		return -EFSCORRUPTED;
202 	}
203 
204 	if (!xfs_has_rmapbt(mp)) {
205 		xfs_debug(mp, "notify_failure() needs rmapbt enabled!");
206 		return -EOPNOTSUPP;
207 	}
208 
209 	ddev_start = mp->m_ddev_targp->bt_dax_part_off;
210 	ddev_end = ddev_start + bdev_nr_bytes(mp->m_ddev_targp->bt_bdev) - 1;
211 
212 	/* Ignore the range out of filesystem area */
213 	if (offset + len < ddev_start)
214 		return -ENXIO;
215 	if (offset > ddev_end)
216 		return -ENXIO;
217 
218 	/* Calculate the real range when it touches the boundary */
219 	if (offset > ddev_start)
220 		offset -= ddev_start;
221 	else {
222 		len -= ddev_start - offset;
223 		offset = 0;
224 	}
225 	if (offset + len > ddev_end)
226 		len -= ddev_end - offset;
227 
228 	return xfs_dax_notify_ddev_failure(mp, BTOBB(offset), BTOBB(len),
229 			mf_flags);
230 }
231 
232 const struct dax_holder_operations xfs_dax_holder_operations = {
233 	.notify_failure		= xfs_dax_notify_failure,
234 };
235