1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (c) 2000-2001 Christoph Hellwig.
4 */
5
6/*
7 * Veritas filesystem driver - filesystem to disk block mapping.
8 */
9#include <linux/fs.h>
10#include <linux/buffer_head.h>
11#include <linux/kernel.h>
12
13#include "vxfs.h"
14#include "vxfs_inode.h"
15#include "vxfs_extern.h"
16
17
18#ifdef DIAGNOSTIC
19static void
20vxfs_typdump(struct vxfs_typed *typ)
21{
22 printk(KERN_DEBUG "type=%Lu ", typ->vt_hdr >> VXFS_TYPED_TYPESHIFT);
23 printk("offset=%Lx ", typ->vt_hdr & VXFS_TYPED_OFFSETMASK);
24 printk("block=%x ", typ->vt_block);
25 printk("size=%x\n", typ->vt_size);
26}
27#endif
28
29/**
30 * vxfs_bmap_ext4 - do bmap for ext4 extents
31 * @ip: pointer to the inode we do bmap for
32 * @iblock: logical block.
33 *
34 * Description:
35 * vxfs_bmap_ext4 performs the bmap operation for inodes with
36 * ext4-style extents (which are much like the traditional UNIX
37 * inode organisation).
38 *
39 * Returns:
40 * The physical block number on success, else Zero.
41 */
42static daddr_t
43vxfs_bmap_ext4(struct inode *ip, long bn)
44{
45 struct super_block *sb = ip->i_sb;
46 struct vxfs_inode_info *vip = VXFS_INO(inode: ip);
47 struct vxfs_sb_info *sbi = VXFS_SBI(sb);
48 unsigned long bsize = sb->s_blocksize;
49 u32 indsize = fs32_to_cpu(sbi, a: vip->vii_ext4.ve4_indsize);
50 int i;
51
52 if (indsize > sb->s_blocksize)
53 goto fail_size;
54
55 for (i = 0; i < VXFS_NDADDR; i++) {
56 struct direct *d = vip->vii_ext4.ve4_direct + i;
57 if (bn >= 0 && bn < fs32_to_cpu(sbi, a: d->size))
58 return (bn + fs32_to_cpu(sbi, a: d->extent));
59 bn -= fs32_to_cpu(sbi, a: d->size);
60 }
61
62 if ((bn / (indsize * indsize * bsize / 4)) == 0) {
63 struct buffer_head *buf;
64 daddr_t bno;
65 __fs32 *indir;
66
67 buf = sb_bread(sb,
68 block: fs32_to_cpu(sbi, a: vip->vii_ext4.ve4_indir[0]));
69 if (!buf || !buffer_mapped(bh: buf))
70 goto fail_buf;
71
72 indir = (__fs32 *)buf->b_data;
73 bno = fs32_to_cpu(sbi, a: indir[(bn / indsize) % (indsize * bn)]) +
74 (bn % indsize);
75
76 brelse(bh: buf);
77 return bno;
78 } else
79 printk(KERN_WARNING "no matching indir?");
80
81 return 0;
82
83fail_size:
84 printk("vxfs: indirect extent too big!\n");
85fail_buf:
86 return 0;
87}
88
89/**
90 * vxfs_bmap_indir - recursion for vxfs_bmap_typed
91 * @ip: pointer to the inode we do bmap for
92 * @indir: indirect block we start reading at
93 * @size: size of the typed area to search
94 * @block: partially result from further searches
95 *
96 * Description:
97 * vxfs_bmap_indir reads a &struct vxfs_typed at @indir
98 * and performs the type-defined action.
99 *
100 * Return Value:
101 * The physical block number on success, else Zero.
102 *
103 * Note:
104 * Kernelstack is rare. Unrecurse?
105 */
106static daddr_t
107vxfs_bmap_indir(struct inode *ip, long indir, int size, long block)
108{
109 struct vxfs_sb_info *sbi = VXFS_SBI(ip->i_sb);
110 struct buffer_head *bp = NULL;
111 daddr_t pblock = 0;
112 int i;
113
114 for (i = 0; i < size * VXFS_TYPED_PER_BLOCK(ip->i_sb); i++) {
115 struct vxfs_typed *typ;
116 int64_t off;
117
118 bp = sb_bread(sb: ip->i_sb,
119 block: indir + (i / VXFS_TYPED_PER_BLOCK(ip->i_sb)));
120 if (!bp || !buffer_mapped(bh: bp))
121 return 0;
122
123 typ = ((struct vxfs_typed *)bp->b_data) +
124 (i % VXFS_TYPED_PER_BLOCK(ip->i_sb));
125 off = fs64_to_cpu(sbi, a: typ->vt_hdr) & VXFS_TYPED_OFFSETMASK;
126
127 if (block < off) {
128 brelse(bh: bp);
129 continue;
130 }
131
132 switch ((u_int32_t)(fs64_to_cpu(sbi, a: typ->vt_hdr) >>
133 VXFS_TYPED_TYPESHIFT)) {
134 case VXFS_TYPED_INDIRECT:
135 pblock = vxfs_bmap_indir(ip,
136 indir: fs32_to_cpu(sbi, a: typ->vt_block),
137 size: fs32_to_cpu(sbi, a: typ->vt_size),
138 block: block - off);
139 if (pblock == -2)
140 break;
141 goto out;
142 case VXFS_TYPED_DATA:
143 if ((block - off) >= fs32_to_cpu(sbi, a: typ->vt_size))
144 break;
145 pblock = fs32_to_cpu(sbi, a: typ->vt_block) + block - off;
146 goto out;
147 case VXFS_TYPED_INDIRECT_DEV4:
148 case VXFS_TYPED_DATA_DEV4: {
149 struct vxfs_typed_dev4 *typ4 =
150 (struct vxfs_typed_dev4 *)typ;
151
152 printk(KERN_INFO "\n\nTYPED_DEV4 detected!\n");
153 printk(KERN_INFO "block: %llu\tsize: %lld\tdev: %d\n",
154 fs64_to_cpu(sbi, typ4->vd4_block),
155 fs64_to_cpu(sbi, typ4->vd4_size),
156 fs32_to_cpu(sbi, typ4->vd4_dev));
157 goto fail;
158 }
159 default:
160 printk(KERN_ERR "%s:%d vt_hdr %llu\n", __func__,
161 __LINE__, fs64_to_cpu(sbi, typ->vt_hdr));
162 BUG();
163 }
164 brelse(bh: bp);
165 }
166
167fail:
168 pblock = 0;
169out:
170 brelse(bh: bp);
171 return (pblock);
172}
173
174/**
175 * vxfs_bmap_typed - bmap for typed extents
176 * @ip: pointer to the inode we do bmap for
177 * @iblock: logical block
178 *
179 * Description:
180 * Performs the bmap operation for typed extents.
181 *
182 * Return Value:
183 * The physical block number on success, else Zero.
184 */
185static daddr_t
186vxfs_bmap_typed(struct inode *ip, long iblock)
187{
188 struct vxfs_inode_info *vip = VXFS_INO(inode: ip);
189 struct vxfs_sb_info *sbi = VXFS_SBI(ip->i_sb);
190 daddr_t pblock = 0;
191 int i;
192
193 for (i = 0; i < VXFS_NTYPED; i++) {
194 struct vxfs_typed *typ = vip->vii_org.typed + i;
195 u64 hdr = fs64_to_cpu(sbi, a: typ->vt_hdr);
196 int64_t off = (hdr & VXFS_TYPED_OFFSETMASK);
197
198#ifdef DIAGNOSTIC
199 vxfs_typdump(typ);
200#endif
201 if (iblock < off)
202 continue;
203 switch ((u32)(hdr >> VXFS_TYPED_TYPESHIFT)) {
204 case VXFS_TYPED_INDIRECT:
205 pblock = vxfs_bmap_indir(ip,
206 indir: fs32_to_cpu(sbi, a: typ->vt_block),
207 size: fs32_to_cpu(sbi, a: typ->vt_size),
208 block: iblock - off);
209 if (pblock == -2)
210 break;
211 return (pblock);
212 case VXFS_TYPED_DATA:
213 if ((iblock - off) < fs32_to_cpu(sbi, a: typ->vt_size))
214 return (fs32_to_cpu(sbi, a: typ->vt_block) +
215 iblock - off);
216 break;
217 case VXFS_TYPED_INDIRECT_DEV4:
218 case VXFS_TYPED_DATA_DEV4: {
219 struct vxfs_typed_dev4 *typ4 =
220 (struct vxfs_typed_dev4 *)typ;
221
222 printk(KERN_INFO "\n\nTYPED_DEV4 detected!\n");
223 printk(KERN_INFO "block: %llu\tsize: %lld\tdev: %d\n",
224 fs64_to_cpu(sbi, typ4->vd4_block),
225 fs64_to_cpu(sbi, typ4->vd4_size),
226 fs32_to_cpu(sbi, typ4->vd4_dev));
227 return 0;
228 }
229 default:
230 BUG();
231 }
232 }
233
234 return 0;
235}
236
237/**
238 * vxfs_bmap1 - vxfs-internal bmap operation
239 * @ip: pointer to the inode we do bmap for
240 * @iblock: logical block
241 *
242 * Description:
243 * vxfs_bmap1 perfoms a logical to physical block mapping
244 * for vxfs-internal purposes.
245 *
246 * Return Value:
247 * The physical block number on success, else Zero.
248 */
249daddr_t
250vxfs_bmap1(struct inode *ip, long iblock)
251{
252 struct vxfs_inode_info *vip = VXFS_INO(inode: ip);
253
254 if (VXFS_ISEXT4(vip))
255 return vxfs_bmap_ext4(ip, bn: iblock);
256 if (VXFS_ISTYPED(vip))
257 return vxfs_bmap_typed(ip, iblock);
258 if (VXFS_ISNONE(vip))
259 goto unsupp;
260 if (VXFS_ISIMMED(vip))
261 goto unsupp;
262
263 printk(KERN_WARNING "vxfs: inode %ld has no valid orgtype (%x)\n",
264 ip->i_ino, vip->vii_orgtype);
265 BUG();
266
267unsupp:
268 printk(KERN_WARNING "vxfs: inode %ld has an unsupported orgtype (%x)\n",
269 ip->i_ino, vip->vii_orgtype);
270 return 0;
271}
272

source code of linux/fs/freevxfs/vxfs_bmap.c