1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright (c) 2016-2021 Christoph Hellwig.
4 */
5 #include <linux/iomap.h>
6 #include <linux/fiemap.h>
7 #include <linux/pagemap.h>
8
iomap_to_fiemap(struct fiemap_extent_info * fi,const struct iomap * iomap,u32 flags)9 static int iomap_to_fiemap(struct fiemap_extent_info *fi,
10 const struct iomap *iomap, u32 flags)
11 {
12 switch (iomap->type) {
13 case IOMAP_HOLE:
14 /* skip holes */
15 return 0;
16 case IOMAP_DELALLOC:
17 flags |= FIEMAP_EXTENT_DELALLOC | FIEMAP_EXTENT_UNKNOWN;
18 break;
19 case IOMAP_MAPPED:
20 break;
21 case IOMAP_UNWRITTEN:
22 flags |= FIEMAP_EXTENT_UNWRITTEN;
23 break;
24 case IOMAP_INLINE:
25 flags |= FIEMAP_EXTENT_DATA_INLINE;
26 break;
27 }
28
29 if (iomap->flags & IOMAP_F_MERGED)
30 flags |= FIEMAP_EXTENT_MERGED;
31 if (iomap->flags & IOMAP_F_SHARED)
32 flags |= FIEMAP_EXTENT_SHARED;
33
34 return fiemap_fill_next_extent(fi, iomap->offset,
35 iomap->addr != IOMAP_NULL_ADDR ? iomap->addr : 0,
36 iomap->length, flags);
37 }
38
iomap_fiemap_iter(struct iomap_iter * iter,struct fiemap_extent_info * fi,struct iomap * prev)39 static int iomap_fiemap_iter(struct iomap_iter *iter,
40 struct fiemap_extent_info *fi, struct iomap *prev)
41 {
42 int ret;
43
44 if (iter->iomap.type == IOMAP_HOLE)
45 goto advance;
46
47 ret = iomap_to_fiemap(fi, prev, 0);
48 *prev = iter->iomap;
49 if (ret < 0)
50 return ret;
51 if (ret == 1) /* extent array full */
52 return 0;
53
54 advance:
55 return iomap_iter_advance_full(iter);
56 }
57
iomap_fiemap(struct inode * inode,struct fiemap_extent_info * fi,u64 start,u64 len,const struct iomap_ops * ops)58 int iomap_fiemap(struct inode *inode, struct fiemap_extent_info *fi,
59 u64 start, u64 len, const struct iomap_ops *ops)
60 {
61 struct iomap_iter iter = {
62 .inode = inode,
63 .pos = start,
64 .len = len,
65 .flags = IOMAP_REPORT,
66 };
67 struct iomap prev = {
68 .type = IOMAP_HOLE,
69 };
70 int ret;
71
72 ret = fiemap_prep(inode, fi, start, &iter.len, 0);
73 if (ret)
74 return ret;
75
76 while ((ret = iomap_iter(&iter, ops)) > 0)
77 iter.status = iomap_fiemap_iter(&iter, fi, &prev);
78
79 if (prev.type != IOMAP_HOLE) {
80 ret = iomap_to_fiemap(fi, &prev, FIEMAP_EXTENT_LAST);
81 if (ret < 0)
82 return ret;
83 }
84
85 /* inode with no (attribute) mapping will give ENOENT */
86 if (ret < 0 && ret != -ENOENT)
87 return ret;
88 return 0;
89 }
90 EXPORT_SYMBOL_GPL(iomap_fiemap);
91
92 /* legacy ->bmap interface. 0 is the error return (!) */
93 sector_t
iomap_bmap(struct address_space * mapping,sector_t bno,const struct iomap_ops * ops)94 iomap_bmap(struct address_space *mapping, sector_t bno,
95 const struct iomap_ops *ops)
96 {
97 struct iomap_iter iter = {
98 .inode = mapping->host,
99 .pos = (loff_t)bno << mapping->host->i_blkbits,
100 .len = i_blocksize(mapping->host),
101 .flags = IOMAP_REPORT,
102 };
103 const unsigned int blkshift = mapping->host->i_blkbits - SECTOR_SHIFT;
104 int ret;
105
106 if (filemap_write_and_wait(mapping))
107 return 0;
108
109 bno = 0;
110 while ((ret = iomap_iter(&iter, ops)) > 0) {
111 if (iter.iomap.type == IOMAP_MAPPED)
112 bno = iomap_sector(&iter.iomap, iter.pos) >> blkshift;
113 /* leave iter.status unset to abort loop */
114 }
115 if (ret)
116 return 0;
117
118 return bno;
119 }
120 EXPORT_SYMBOL_GPL(iomap_bmap);
121