1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright (c) 2016-2018 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
11 struct fiemap_ctx {
12 struct fiemap_extent_info *fi;
13 struct iomap prev;
14 };
15
iomap_to_fiemap(struct fiemap_extent_info * fi,struct iomap * iomap,u32 flags)16 static int iomap_to_fiemap(struct fiemap_extent_info *fi,
17 struct iomap *iomap, u32 flags)
18 {
19 switch (iomap->type) {
20 case IOMAP_HOLE:
21 /* skip holes */
22 return 0;
23 case IOMAP_DELALLOC:
24 flags |= FIEMAP_EXTENT_DELALLOC | FIEMAP_EXTENT_UNKNOWN;
25 break;
26 case IOMAP_MAPPED:
27 break;
28 case IOMAP_UNWRITTEN:
29 flags |= FIEMAP_EXTENT_UNWRITTEN;
30 break;
31 case IOMAP_INLINE:
32 flags |= FIEMAP_EXTENT_DATA_INLINE;
33 break;
34 }
35
36 if (iomap->flags & IOMAP_F_MERGED)
37 flags |= FIEMAP_EXTENT_MERGED;
38 if (iomap->flags & IOMAP_F_SHARED)
39 flags |= FIEMAP_EXTENT_SHARED;
40
41 return fiemap_fill_next_extent(fi, iomap->offset,
42 iomap->addr != IOMAP_NULL_ADDR ? iomap->addr : 0,
43 iomap->length, flags);
44 }
45
46 static loff_t
iomap_fiemap_actor(struct inode * inode,loff_t pos,loff_t length,void * data,struct iomap * iomap,struct iomap * srcmap)47 iomap_fiemap_actor(struct inode *inode, loff_t pos, loff_t length, void *data,
48 struct iomap *iomap, struct iomap *srcmap)
49 {
50 struct fiemap_ctx *ctx = data;
51 loff_t ret = length;
52
53 if (iomap->type == IOMAP_HOLE)
54 return length;
55
56 ret = iomap_to_fiemap(ctx->fi, &ctx->prev, 0);
57 ctx->prev = *iomap;
58 switch (ret) {
59 case 0: /* success */
60 return length;
61 case 1: /* extent array full */
62 return 0;
63 default:
64 return ret;
65 }
66 }
67
iomap_fiemap(struct inode * inode,struct fiemap_extent_info * fi,u64 start,u64 len,const struct iomap_ops * ops)68 int iomap_fiemap(struct inode *inode, struct fiemap_extent_info *fi,
69 u64 start, u64 len, const struct iomap_ops *ops)
70 {
71 struct fiemap_ctx ctx;
72 loff_t ret;
73
74 memset(&ctx, 0, sizeof(ctx));
75 ctx.fi = fi;
76 ctx.prev.type = IOMAP_HOLE;
77
78 ret = fiemap_prep(inode, fi, start, &len, 0);
79 if (ret)
80 return ret;
81
82 while (len > 0) {
83 ret = iomap_apply(inode, start, len, IOMAP_REPORT, ops, &ctx,
84 iomap_fiemap_actor);
85 /* inode with no (attribute) mapping will give ENOENT */
86 if (ret == -ENOENT)
87 break;
88 if (ret < 0)
89 return ret;
90 if (ret == 0)
91 break;
92
93 start += ret;
94 len -= ret;
95 }
96
97 if (ctx.prev.type != IOMAP_HOLE) {
98 ret = iomap_to_fiemap(fi, &ctx.prev, FIEMAP_EXTENT_LAST);
99 if (ret < 0)
100 return ret;
101 }
102
103 return 0;
104 }
105 EXPORT_SYMBOL_GPL(iomap_fiemap);
106
107 static loff_t
iomap_bmap_actor(struct inode * inode,loff_t pos,loff_t length,void * data,struct iomap * iomap,struct iomap * srcmap)108 iomap_bmap_actor(struct inode *inode, loff_t pos, loff_t length,
109 void *data, struct iomap *iomap, struct iomap *srcmap)
110 {
111 sector_t *bno = data, addr;
112
113 if (iomap->type == IOMAP_MAPPED) {
114 addr = (pos - iomap->offset + iomap->addr) >> inode->i_blkbits;
115 *bno = addr;
116 }
117 return 0;
118 }
119
120 /* legacy ->bmap interface. 0 is the error return (!) */
121 sector_t
iomap_bmap(struct address_space * mapping,sector_t bno,const struct iomap_ops * ops)122 iomap_bmap(struct address_space *mapping, sector_t bno,
123 const struct iomap_ops *ops)
124 {
125 struct inode *inode = mapping->host;
126 loff_t pos = bno << inode->i_blkbits;
127 unsigned blocksize = i_blocksize(inode);
128 int ret;
129
130 if (filemap_write_and_wait(mapping))
131 return 0;
132
133 bno = 0;
134 ret = iomap_apply(inode, pos, blocksize, 0, ops, &bno,
135 iomap_bmap_actor);
136 if (ret)
137 return 0;
138 return bno;
139 }
140 EXPORT_SYMBOL_GPL(iomap_bmap);
141