1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright (c) 2016-2021 Christoph Hellwig.
4 */
5 #include <linux/module.h>
6 #include <linux/compiler.h>
7 #include <linux/fs.h>
8 #include <linux/iomap.h>
9 #include <linux/fiemap.h>
10
iomap_to_fiemap(struct fiemap_extent_info * fi,const struct iomap * iomap,u32 flags)11 static int iomap_to_fiemap(struct fiemap_extent_info *fi,
12 const struct iomap *iomap, u32 flags)
13 {
14 switch (iomap->type) {
15 case IOMAP_HOLE:
16 /* skip holes */
17 return 0;
18 case IOMAP_DELALLOC:
19 flags |= FIEMAP_EXTENT_DELALLOC | FIEMAP_EXTENT_UNKNOWN;
20 break;
21 case IOMAP_MAPPED:
22 break;
23 case IOMAP_UNWRITTEN:
24 flags |= FIEMAP_EXTENT_UNWRITTEN;
25 break;
26 case IOMAP_INLINE:
27 flags |= FIEMAP_EXTENT_DATA_INLINE;
28 break;
29 }
30
31 if (iomap->flags & IOMAP_F_MERGED)
32 flags |= FIEMAP_EXTENT_MERGED;
33 if (iomap->flags & IOMAP_F_SHARED)
34 flags |= FIEMAP_EXTENT_SHARED;
35
36 return fiemap_fill_next_extent(fi, iomap->offset,
37 iomap->addr != IOMAP_NULL_ADDR ? iomap->addr : 0,
38 iomap->length, flags);
39 }
40
iomap_fiemap_iter(const struct iomap_iter * iter,struct fiemap_extent_info * fi,struct iomap * prev)41 static loff_t iomap_fiemap_iter(const struct iomap_iter *iter,
42 struct fiemap_extent_info *fi, struct iomap *prev)
43 {
44 int ret;
45
46 if (iter->iomap.type == IOMAP_HOLE)
47 return iomap_length(iter);
48
49 ret = iomap_to_fiemap(fi, prev, 0);
50 *prev = iter->iomap;
51 switch (ret) {
52 case 0: /* success */
53 return iomap_length(iter);
54 case 1: /* extent array full */
55 return 0;
56 default: /* error */
57 return ret;
58 }
59 }
60
iomap_fiemap(struct inode * inode,struct fiemap_extent_info * fi,u64 start,u64 len,const struct iomap_ops * ops)61 int iomap_fiemap(struct inode *inode, struct fiemap_extent_info *fi,
62 u64 start, u64 len, const struct iomap_ops *ops)
63 {
64 struct iomap_iter iter = {
65 .inode = inode,
66 .pos = start,
67 .len = len,
68 .flags = IOMAP_REPORT,
69 };
70 struct iomap prev = {
71 .type = IOMAP_HOLE,
72 };
73 int ret;
74
75 ret = fiemap_prep(inode, fi, start, &iter.len, 0);
76 if (ret)
77 return ret;
78
79 while ((ret = iomap_iter(&iter, ops)) > 0)
80 iter.processed = iomap_fiemap_iter(&iter, fi, &prev);
81
82 if (prev.type != IOMAP_HOLE) {
83 ret = iomap_to_fiemap(fi, &prev, FIEMAP_EXTENT_LAST);
84 if (ret < 0)
85 return ret;
86 }
87
88 /* inode with no (attribute) mapping will give ENOENT */
89 if (ret < 0 && ret != -ENOENT)
90 return ret;
91 return 0;
92 }
93 EXPORT_SYMBOL_GPL(iomap_fiemap);
94
95 /* legacy ->bmap interface. 0 is the error return (!) */
96 sector_t
iomap_bmap(struct address_space * mapping,sector_t bno,const struct iomap_ops * ops)97 iomap_bmap(struct address_space *mapping, sector_t bno,
98 const struct iomap_ops *ops)
99 {
100 struct iomap_iter iter = {
101 .inode = mapping->host,
102 .pos = (loff_t)bno << mapping->host->i_blkbits,
103 .len = i_blocksize(mapping->host),
104 .flags = IOMAP_REPORT,
105 };
106 const unsigned int blkshift = mapping->host->i_blkbits - SECTOR_SHIFT;
107 int ret;
108
109 if (filemap_write_and_wait(mapping))
110 return 0;
111
112 bno = 0;
113 while ((ret = iomap_iter(&iter, ops)) > 0) {
114 if (iter.iomap.type == IOMAP_MAPPED)
115 bno = iomap_sector(&iter.iomap, iter.pos) >> blkshift;
116 /* leave iter.processed unset to abort loop */
117 }
118 if (ret)
119 return 0;
120
121 return bno;
122 }
123 EXPORT_SYMBOL_GPL(iomap_bmap);
124