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 #include <linux/pagemap.h>
11
iomap_to_fiemap(struct fiemap_extent_info * fi,const struct iomap * iomap,u32 flags)12 static int iomap_to_fiemap(struct fiemap_extent_info *fi,
13 const struct iomap *iomap, u32 flags)
14 {
15 switch (iomap->type) {
16 case IOMAP_HOLE:
17 /* skip holes */
18 return 0;
19 case IOMAP_DELALLOC:
20 flags |= FIEMAP_EXTENT_DELALLOC | FIEMAP_EXTENT_UNKNOWN;
21 break;
22 case IOMAP_MAPPED:
23 break;
24 case IOMAP_UNWRITTEN:
25 flags |= FIEMAP_EXTENT_UNWRITTEN;
26 break;
27 case IOMAP_INLINE:
28 flags |= FIEMAP_EXTENT_DATA_INLINE;
29 break;
30 }
31
32 if (iomap->flags & IOMAP_F_MERGED)
33 flags |= FIEMAP_EXTENT_MERGED;
34 if (iomap->flags & IOMAP_F_SHARED)
35 flags |= FIEMAP_EXTENT_SHARED;
36
37 return fiemap_fill_next_extent(fi, iomap->offset,
38 iomap->addr != IOMAP_NULL_ADDR ? iomap->addr : 0,
39 iomap->length, flags);
40 }
41
iomap_fiemap_iter(const struct iomap_iter * iter,struct fiemap_extent_info * fi,struct iomap * prev)42 static loff_t iomap_fiemap_iter(const struct iomap_iter *iter,
43 struct fiemap_extent_info *fi, struct iomap *prev)
44 {
45 int ret;
46
47 if (iter->iomap.type == IOMAP_HOLE)
48 return iomap_length(iter);
49
50 ret = iomap_to_fiemap(fi, prev, 0);
51 *prev = iter->iomap;
52 switch (ret) {
53 case 0: /* success */
54 return iomap_length(iter);
55 case 1: /* extent array full */
56 return 0;
57 default: /* error */
58 return ret;
59 }
60 }
61
iomap_fiemap(struct inode * inode,struct fiemap_extent_info * fi,u64 start,u64 len,const struct iomap_ops * ops)62 int iomap_fiemap(struct inode *inode, struct fiemap_extent_info *fi,
63 u64 start, u64 len, const struct iomap_ops *ops)
64 {
65 struct iomap_iter iter = {
66 .inode = inode,
67 .pos = start,
68 .len = len,
69 .flags = IOMAP_REPORT,
70 };
71 struct iomap prev = {
72 .type = IOMAP_HOLE,
73 };
74 int ret;
75
76 ret = fiemap_prep(inode, fi, start, &iter.len, 0);
77 if (ret)
78 return ret;
79
80 while ((ret = iomap_iter(&iter, ops)) > 0)
81 iter.processed = iomap_fiemap_iter(&iter, fi, &prev);
82
83 if (prev.type != IOMAP_HOLE) {
84 ret = iomap_to_fiemap(fi, &prev, FIEMAP_EXTENT_LAST);
85 if (ret < 0)
86 return ret;
87 }
88
89 /* inode with no (attribute) mapping will give ENOENT */
90 if (ret < 0 && ret != -ENOENT)
91 return ret;
92 return 0;
93 }
94 EXPORT_SYMBOL_GPL(iomap_fiemap);
95
96 /* legacy ->bmap interface. 0 is the error return (!) */
97 sector_t
iomap_bmap(struct address_space * mapping,sector_t bno,const struct iomap_ops * ops)98 iomap_bmap(struct address_space *mapping, sector_t bno,
99 const struct iomap_ops *ops)
100 {
101 struct iomap_iter iter = {
102 .inode = mapping->host,
103 .pos = (loff_t)bno << mapping->host->i_blkbits,
104 .len = i_blocksize(mapping->host),
105 .flags = IOMAP_REPORT,
106 };
107 const unsigned int blkshift = mapping->host->i_blkbits - SECTOR_SHIFT;
108 int ret;
109
110 if (filemap_write_and_wait(mapping))
111 return 0;
112
113 bno = 0;
114 while ((ret = iomap_iter(&iter, ops)) > 0) {
115 if (iter.iomap.type == IOMAP_MAPPED)
116 bno = iomap_sector(&iter.iomap, iter.pos) >> blkshift;
117 /* leave iter.processed unset to abort loop */
118 }
119 if (ret)
120 return 0;
121
122 return bno;
123 }
124 EXPORT_SYMBOL_GPL(iomap_bmap);
125