xref: /linux/fs/xfs/scrub/rcbag.c (revision 79790b6818e96c58fe2bffee1b418c16e64e7b80)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Copyright (c) 2022-2024 Oracle.  All Rights Reserved.
4  * Author: Darrick J. Wong <djwong@kernel.org>
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.h"
12 #include "xfs_trans_resv.h"
13 #include "xfs_mount.h"
14 #include "xfs_defer.h"
15 #include "xfs_btree.h"
16 #include "xfs_buf_mem.h"
17 #include "xfs_btree_mem.h"
18 #include "xfs_error.h"
19 #include "scrub/scrub.h"
20 #include "scrub/rcbag_btree.h"
21 #include "scrub/rcbag.h"
22 #include "scrub/trace.h"
23 
24 struct rcbag {
25 	struct xfs_mount	*mp;
26 	struct xfbtree		xfbtree;
27 	uint64_t		nr_items;
28 };
29 
30 int
rcbag_init(struct xfs_mount * mp,struct xfs_buftarg * btp,struct rcbag ** bagp)31 rcbag_init(
32 	struct xfs_mount	*mp,
33 	struct xfs_buftarg	*btp,
34 	struct rcbag		**bagp)
35 {
36 	struct rcbag		*bag;
37 	int			error;
38 
39 	bag = kzalloc(sizeof(struct rcbag), XCHK_GFP_FLAGS);
40 	if (!bag)
41 		return -ENOMEM;
42 
43 	bag->nr_items = 0;
44 	bag->mp = mp;
45 
46 	error = rcbagbt_mem_init(mp, &bag->xfbtree, btp);
47 	if (error)
48 		goto out_bag;
49 
50 	*bagp = bag;
51 	return 0;
52 
53 out_bag:
54 	kfree(bag);
55 	return error;
56 }
57 
58 void
rcbag_free(struct rcbag ** bagp)59 rcbag_free(
60 	struct rcbag		**bagp)
61 {
62 	struct rcbag		*bag = *bagp;
63 
64 	xfbtree_destroy(&bag->xfbtree);
65 	kfree(bag);
66 	*bagp = NULL;
67 }
68 
69 /* Track an rmap in the refcount bag. */
70 int
rcbag_add(struct rcbag * bag,struct xfs_trans * tp,const struct xfs_rmap_irec * rmap)71 rcbag_add(
72 	struct rcbag			*bag,
73 	struct xfs_trans		*tp,
74 	const struct xfs_rmap_irec	*rmap)
75 {
76 	struct rcbag_rec		bagrec;
77 	struct xfs_mount		*mp = bag->mp;
78 	struct xfs_btree_cur		*cur;
79 	int				has;
80 	int				error;
81 
82 	cur = rcbagbt_mem_cursor(mp, tp, &bag->xfbtree);
83 	error = rcbagbt_lookup_eq(cur, rmap, &has);
84 	if (error)
85 		goto out_cur;
86 
87 	if (has) {
88 		error = rcbagbt_get_rec(cur, &bagrec, &has);
89 		if (error)
90 			goto out_cur;
91 		if (!has) {
92 			error = -EFSCORRUPTED;
93 			goto out_cur;
94 		}
95 
96 		bagrec.rbg_refcount++;
97 		error = rcbagbt_update(cur, &bagrec);
98 		if (error)
99 			goto out_cur;
100 	} else {
101 		bagrec.rbg_startblock = rmap->rm_startblock;
102 		bagrec.rbg_blockcount = rmap->rm_blockcount;
103 		bagrec.rbg_refcount = 1;
104 
105 		error = rcbagbt_insert(cur, &bagrec, &has);
106 		if (error)
107 			goto out_cur;
108 		if (!has) {
109 			error = -EFSCORRUPTED;
110 			goto out_cur;
111 		}
112 	}
113 
114 	xfs_btree_del_cursor(cur, 0);
115 
116 	error = xfbtree_trans_commit(&bag->xfbtree, tp);
117 	if (error)
118 		return error;
119 
120 	bag->nr_items++;
121 	return 0;
122 
123 out_cur:
124 	xfs_btree_del_cursor(cur, error);
125 	xfbtree_trans_cancel(&bag->xfbtree, tp);
126 	return error;
127 }
128 
129 /* Return the number of records in the bag. */
130 uint64_t
rcbag_count(const struct rcbag * rcbag)131 rcbag_count(
132 	const struct rcbag	*rcbag)
133 {
134 	return rcbag->nr_items;
135 }
136 
rcbag_rec_next_bno(const struct rcbag_rec * r)137 static inline uint32_t rcbag_rec_next_bno(const struct rcbag_rec *r)
138 {
139 	return r->rbg_startblock + r->rbg_blockcount;
140 }
141 
142 /*
143  * Find the next block where the refcount changes, given the next rmap we
144  * looked at and the ones we're already tracking.
145  */
146 int
rcbag_next_edge(struct rcbag * bag,struct xfs_trans * tp,const struct xfs_rmap_irec * next_rmap,bool next_valid,uint32_t * next_bnop)147 rcbag_next_edge(
148 	struct rcbag			*bag,
149 	struct xfs_trans		*tp,
150 	const struct xfs_rmap_irec	*next_rmap,
151 	bool				next_valid,
152 	uint32_t			*next_bnop)
153 {
154 	struct rcbag_rec		bagrec;
155 	struct xfs_mount		*mp = bag->mp;
156 	struct xfs_btree_cur		*cur;
157 	uint32_t			next_bno = NULLAGBLOCK;
158 	int				has;
159 	int				error;
160 
161 	if (next_valid)
162 		next_bno = next_rmap->rm_startblock;
163 
164 	cur = rcbagbt_mem_cursor(mp, tp, &bag->xfbtree);
165 	error = xfs_btree_goto_left_edge(cur);
166 	if (error)
167 		goto out_cur;
168 
169 	while (true) {
170 		error = xfs_btree_increment(cur, 0, &has);
171 		if (error)
172 			goto out_cur;
173 		if (!has)
174 			break;
175 
176 		error = rcbagbt_get_rec(cur, &bagrec, &has);
177 		if (error)
178 			goto out_cur;
179 		if (!has) {
180 			error = -EFSCORRUPTED;
181 			goto out_cur;
182 		}
183 
184 		next_bno = min(next_bno, rcbag_rec_next_bno(&bagrec));
185 	}
186 
187 	/*
188 	 * We should have found /something/ because either next_rrm is the next
189 	 * interesting rmap to look at after emitting this refcount extent, or
190 	 * there are other rmaps in rmap_bag contributing to the current
191 	 * sharing count.  But if something is seriously wrong, bail out.
192 	 */
193 	if (next_bno == NULLAGBLOCK) {
194 		error = -EFSCORRUPTED;
195 		goto out_cur;
196 	}
197 
198 	xfs_btree_del_cursor(cur, 0);
199 
200 	*next_bnop = next_bno;
201 	return 0;
202 
203 out_cur:
204 	xfs_btree_del_cursor(cur, error);
205 	return error;
206 }
207 
208 /* Pop all refcount bag records that end at next_bno */
209 int
rcbag_remove_ending_at(struct rcbag * bag,struct xfs_trans * tp,uint32_t next_bno)210 rcbag_remove_ending_at(
211 	struct rcbag		*bag,
212 	struct xfs_trans	*tp,
213 	uint32_t		next_bno)
214 {
215 	struct rcbag_rec	bagrec;
216 	struct xfs_mount	*mp = bag->mp;
217 	struct xfs_btree_cur	*cur;
218 	int			has;
219 	int			error;
220 
221 	/* go to the right edge of the tree */
222 	cur = rcbagbt_mem_cursor(mp, tp, &bag->xfbtree);
223 	memset(&cur->bc_rec, 0xFF, sizeof(cur->bc_rec));
224 	error = xfs_btree_lookup(cur, XFS_LOOKUP_GE, &has);
225 	if (error)
226 		goto out_cur;
227 
228 	while (true) {
229 		error = xfs_btree_decrement(cur, 0, &has);
230 		if (error)
231 			goto out_cur;
232 		if (!has)
233 			break;
234 
235 		error = rcbagbt_get_rec(cur, &bagrec, &has);
236 		if (error)
237 			goto out_cur;
238 		if (!has) {
239 			error = -EFSCORRUPTED;
240 			goto out_cur;
241 		}
242 
243 		if (rcbag_rec_next_bno(&bagrec) != next_bno)
244 			continue;
245 
246 		error = xfs_btree_delete(cur, &has);
247 		if (error)
248 			goto out_cur;
249 		if (!has) {
250 			error = -EFSCORRUPTED;
251 			goto out_cur;
252 		}
253 
254 		bag->nr_items -= bagrec.rbg_refcount;
255 	}
256 
257 	xfs_btree_del_cursor(cur, 0);
258 	return xfbtree_trans_commit(&bag->xfbtree, tp);
259 out_cur:
260 	xfs_btree_del_cursor(cur, error);
261 	xfbtree_trans_cancel(&bag->xfbtree, tp);
262 	return error;
263 }
264 
265 /* Dump the rcbag. */
266 void
rcbag_dump(struct rcbag * bag,struct xfs_trans * tp)267 rcbag_dump(
268 	struct rcbag			*bag,
269 	struct xfs_trans		*tp)
270 {
271 	struct rcbag_rec		bagrec;
272 	struct xfs_mount		*mp = bag->mp;
273 	struct xfs_btree_cur		*cur;
274 	unsigned long long		nr = 0;
275 	int				has;
276 	int				error;
277 
278 	cur = rcbagbt_mem_cursor(mp, tp, &bag->xfbtree);
279 	error = xfs_btree_goto_left_edge(cur);
280 	if (error)
281 		goto out_cur;
282 
283 	while (true) {
284 		error = xfs_btree_increment(cur, 0, &has);
285 		if (error)
286 			goto out_cur;
287 		if (!has)
288 			break;
289 
290 		error = rcbagbt_get_rec(cur, &bagrec, &has);
291 		if (error)
292 			goto out_cur;
293 		if (!has) {
294 			error = -EFSCORRUPTED;
295 			goto out_cur;
296 		}
297 
298 		xfs_err(bag->mp, "[%llu]: bno 0x%x fsbcount 0x%x refcount 0x%llx\n",
299 				nr++,
300 				(unsigned int)bagrec.rbg_startblock,
301 				(unsigned int)bagrec.rbg_blockcount,
302 				(unsigned long long)bagrec.rbg_refcount);
303 	}
304 
305 out_cur:
306 	xfs_btree_del_cursor(cur, error);
307 }
308