xref: /linux/fs/xfs/libxfs/xfs_types.c (revision 52338415)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2000-2002,2005 Silicon Graphics, Inc.
4  * Copyright (C) 2017 Oracle.
5  * All Rights Reserved.
6  */
7 #include "xfs.h"
8 #include "xfs_fs.h"
9 #include "xfs_format.h"
10 #include "xfs_shared.h"
11 #include "xfs_trans_resv.h"
12 #include "xfs_bit.h"
13 #include "xfs_mount.h"
14 
15 /* Find the size of the AG, in blocks. */
16 xfs_agblock_t
17 xfs_ag_block_count(
18 	struct xfs_mount	*mp,
19 	xfs_agnumber_t		agno)
20 {
21 	ASSERT(agno < mp->m_sb.sb_agcount);
22 
23 	if (agno < mp->m_sb.sb_agcount - 1)
24 		return mp->m_sb.sb_agblocks;
25 	return mp->m_sb.sb_dblocks - (agno * mp->m_sb.sb_agblocks);
26 }
27 
28 /*
29  * Verify that an AG block number pointer neither points outside the AG
30  * nor points at static metadata.
31  */
32 bool
33 xfs_verify_agbno(
34 	struct xfs_mount	*mp,
35 	xfs_agnumber_t		agno,
36 	xfs_agblock_t		agbno)
37 {
38 	xfs_agblock_t		eoag;
39 
40 	eoag = xfs_ag_block_count(mp, agno);
41 	if (agbno >= eoag)
42 		return false;
43 	if (agbno <= XFS_AGFL_BLOCK(mp))
44 		return false;
45 	return true;
46 }
47 
48 /*
49  * Verify that an FS block number pointer neither points outside the
50  * filesystem nor points at static AG metadata.
51  */
52 bool
53 xfs_verify_fsbno(
54 	struct xfs_mount	*mp,
55 	xfs_fsblock_t		fsbno)
56 {
57 	xfs_agnumber_t		agno = XFS_FSB_TO_AGNO(mp, fsbno);
58 
59 	if (agno >= mp->m_sb.sb_agcount)
60 		return false;
61 	return xfs_verify_agbno(mp, agno, XFS_FSB_TO_AGBNO(mp, fsbno));
62 }
63 
64 /* Calculate the first and last possible inode number in an AG. */
65 void
66 xfs_agino_range(
67 	struct xfs_mount	*mp,
68 	xfs_agnumber_t		agno,
69 	xfs_agino_t		*first,
70 	xfs_agino_t		*last)
71 {
72 	xfs_agblock_t		bno;
73 	xfs_agblock_t		eoag;
74 
75 	eoag = xfs_ag_block_count(mp, agno);
76 
77 	/*
78 	 * Calculate the first inode, which will be in the first
79 	 * cluster-aligned block after the AGFL.
80 	 */
81 	bno = round_up(XFS_AGFL_BLOCK(mp) + 1, M_IGEO(mp)->cluster_align);
82 	*first = XFS_AGB_TO_AGINO(mp, bno);
83 
84 	/*
85 	 * Calculate the last inode, which will be at the end of the
86 	 * last (aligned) cluster that can be allocated in the AG.
87 	 */
88 	bno = round_down(eoag, M_IGEO(mp)->cluster_align);
89 	*last = XFS_AGB_TO_AGINO(mp, bno) - 1;
90 }
91 
92 /*
93  * Verify that an AG inode number pointer neither points outside the AG
94  * nor points at static metadata.
95  */
96 bool
97 xfs_verify_agino(
98 	struct xfs_mount	*mp,
99 	xfs_agnumber_t		agno,
100 	xfs_agino_t		agino)
101 {
102 	xfs_agino_t		first;
103 	xfs_agino_t		last;
104 
105 	xfs_agino_range(mp, agno, &first, &last);
106 	return agino >= first && agino <= last;
107 }
108 
109 /*
110  * Verify that an AG inode number pointer neither points outside the AG
111  * nor points at static metadata, or is NULLAGINO.
112  */
113 bool
114 xfs_verify_agino_or_null(
115 	struct xfs_mount	*mp,
116 	xfs_agnumber_t		agno,
117 	xfs_agino_t		agino)
118 {
119 	return agino == NULLAGINO || xfs_verify_agino(mp, agno, agino);
120 }
121 
122 /*
123  * Verify that an FS inode number pointer neither points outside the
124  * filesystem nor points at static AG metadata.
125  */
126 bool
127 xfs_verify_ino(
128 	struct xfs_mount	*mp,
129 	xfs_ino_t		ino)
130 {
131 	xfs_agnumber_t		agno = XFS_INO_TO_AGNO(mp, ino);
132 	xfs_agino_t		agino = XFS_INO_TO_AGINO(mp, ino);
133 
134 	if (agno >= mp->m_sb.sb_agcount)
135 		return false;
136 	if (XFS_AGINO_TO_INO(mp, agno, agino) != ino)
137 		return false;
138 	return xfs_verify_agino(mp, agno, agino);
139 }
140 
141 /* Is this an internal inode number? */
142 bool
143 xfs_internal_inum(
144 	struct xfs_mount	*mp,
145 	xfs_ino_t		ino)
146 {
147 	return ino == mp->m_sb.sb_rbmino || ino == mp->m_sb.sb_rsumino ||
148 		(xfs_sb_version_hasquota(&mp->m_sb) &&
149 		 xfs_is_quota_inode(&mp->m_sb, ino));
150 }
151 
152 /*
153  * Verify that a directory entry's inode number doesn't point at an internal
154  * inode, empty space, or static AG metadata.
155  */
156 bool
157 xfs_verify_dir_ino(
158 	struct xfs_mount	*mp,
159 	xfs_ino_t		ino)
160 {
161 	if (xfs_internal_inum(mp, ino))
162 		return false;
163 	return xfs_verify_ino(mp, ino);
164 }
165 
166 /*
167  * Verify that an realtime block number pointer doesn't point off the
168  * end of the realtime device.
169  */
170 bool
171 xfs_verify_rtbno(
172 	struct xfs_mount	*mp,
173 	xfs_rtblock_t		rtbno)
174 {
175 	return rtbno < mp->m_sb.sb_rblocks;
176 }
177 
178 /* Calculate the range of valid icount values. */
179 void
180 xfs_icount_range(
181 	struct xfs_mount	*mp,
182 	unsigned long long	*min,
183 	unsigned long long	*max)
184 {
185 	unsigned long long	nr_inos = 0;
186 	xfs_agnumber_t		agno;
187 
188 	/* root, rtbitmap, rtsum all live in the first chunk */
189 	*min = XFS_INODES_PER_CHUNK;
190 
191 	for (agno = 0; agno < mp->m_sb.sb_agcount; agno++) {
192 		xfs_agino_t	first, last;
193 
194 		xfs_agino_range(mp, agno, &first, &last);
195 		nr_inos += last - first + 1;
196 	}
197 	*max = nr_inos;
198 }
199 
200 /* Sanity-checking of inode counts. */
201 bool
202 xfs_verify_icount(
203 	struct xfs_mount	*mp,
204 	unsigned long long	icount)
205 {
206 	unsigned long long	min, max;
207 
208 	xfs_icount_range(mp, &min, &max);
209 	return icount >= min && icount <= max;
210 }
211 
212 /* Sanity-checking of dir/attr block offsets. */
213 bool
214 xfs_verify_dablk(
215 	struct xfs_mount	*mp,
216 	xfs_fileoff_t		dabno)
217 {
218 	xfs_dablk_t		max_dablk = -1U;
219 
220 	return dabno <= max_dablk;
221 }
222