xref: /openbmc/linux/arch/um/drivers/cow.h (revision 7fe2f639)
1 #ifndef __COW_H__
2 #define __COW_H__
3 
4 #include <asm/types.h>
5 
6 #if defined(__KERNEL__)
7 
8 # include <asm/byteorder.h>
9 
10 # if defined(__BIG_ENDIAN)
11 #	define ntohll(x) (x)
12 #	define htonll(x) (x)
13 # elif defined(__LITTLE_ENDIAN)
14 #	define ntohll(x)  be64_to_cpu(x)
15 #	define htonll(x)  cpu_to_be64(x)
16 # else
17 #	error "Could not determine byte order"
18 # endif
19 
20 #else
21 /* For the definition of ntohl, htonl and __BYTE_ORDER */
22 #include <endian.h>
23 #include <netinet/in.h>
24 #if defined(__BYTE_ORDER)
25 
26 #  if __BYTE_ORDER == __BIG_ENDIAN
27 #	define ntohll(x) (x)
28 #	define htonll(x) (x)
29 #  elif __BYTE_ORDER == __LITTLE_ENDIAN
30 #	define ntohll(x)  bswap_64(x)
31 #	define htonll(x)  bswap_64(x)
32 #  else
33 #	error "Could not determine byte order: __BYTE_ORDER uncorrectly defined"
34 #  endif
35 
36 #else  /* ! defined(__BYTE_ORDER) */
37 #	error "Could not determine byte order: __BYTE_ORDER not defined"
38 #endif
39 #endif /* ! defined(__KERNEL__) */
40 
41 extern int init_cow_file(int fd, char *cow_file, char *backing_file,
42 			 int sectorsize, int alignment, int *bitmap_offset_out,
43 			 unsigned long *bitmap_len_out, int *data_offset_out);
44 
45 extern int file_reader(__u64 offset, char *buf, int len, void *arg);
46 extern int read_cow_header(int (*reader)(__u64, char *, int, void *),
47 			   void *arg, __u32 *version_out,
48 			   char **backing_file_out, time_t *mtime_out,
49 			   unsigned long long *size_out, int *sectorsize_out,
50 			   __u32 *align_out, int *bitmap_offset_out);
51 
52 extern int write_cow_header(char *cow_file, int fd, char *backing_file,
53 			    int sectorsize, int alignment,
54 			    unsigned long long *size);
55 
56 extern void cow_sizes(int version, __u64 size, int sectorsize, int align,
57 		      int bitmap_offset, unsigned long *bitmap_len_out,
58 		      int *data_offset_out);
59 
60 #endif
61 
62 /*
63  * ---------------------------------------------------------------------------
64  * Local variables:
65  * c-file-style: "linux"
66  * End:
67  */
68