xref: /kvmtool/include/kvm/disk-image.h (revision 3fdf659d959233a543d1f29a358f8da994cec0fb)
19f532d00SPekka Enberg #ifndef KVM__DISK_IMAGE_H
29f532d00SPekka Enberg #define KVM__DISK_IMAGE_H
39f532d00SPekka Enberg 
4*3fdf659dSSasha Levin #include <linux/types.h>
59ac38fe1SSasha Levin #include <stdbool.h>
670b53f25SSasha Levin #include <sys/uio.h>
79f532d00SPekka Enberg 
82924f993SAsias He #define SECTOR_SHIFT		9
92924f993SAsias He #define SECTOR_SIZE		(1UL << SECTOR_SHIFT)
102924f993SAsias He 
11499f3bedSPekka Enberg struct disk_image;
12499f3bedSPekka Enberg 
13499f3bedSPekka Enberg struct disk_image_operations {
14*3fdf659dSSasha Levin 	int (*read_sector)(struct disk_image *self, u64 sector, void *dst, u32 dst_len);
15*3fdf659dSSasha Levin 	int (*write_sector)(struct disk_image *self, u64 sector, void *src, u32 src_len);
16*3fdf659dSSasha Levin 	ssize_t (*read_sector_iov)(struct disk_image *self, u64 sector, const struct iovec *iov, int iovcount);
17*3fdf659dSSasha Levin 	ssize_t (*write_sector_iov)(struct disk_image *self, u64 sector, const struct iovec *iov, int iovcount);
18499f3bedSPekka Enberg 	void (*close)(struct disk_image *self);
19499f3bedSPekka Enberg };
20499f3bedSPekka Enberg 
219f532d00SPekka Enberg struct disk_image {
229f532d00SPekka Enberg 	int				fd;
23*3fdf659dSSasha Levin 	u64				size;
24499f3bedSPekka Enberg 	struct disk_image_operations	*ops;
25499f3bedSPekka Enberg 	void				*priv;
269f532d00SPekka Enberg };
279f532d00SPekka Enberg 
289ac38fe1SSasha Levin struct disk_image *disk_image__open(const char *filename, bool readonly);
29*3fdf659dSSasha Levin struct disk_image *disk_image__new(int fd, u64 size, struct disk_image_operations *ops);
30*3fdf659dSSasha Levin struct disk_image *disk_image__new_readonly(int fd, u64 size, struct disk_image_operations *ops);
319f532d00SPekka Enberg void disk_image__close(struct disk_image *self);
32499f3bedSPekka Enberg 
33*3fdf659dSSasha Levin static inline int disk_image__read_sector(struct disk_image *self, u64 sector, void *dst, u32 dst_len)
34499f3bedSPekka Enberg {
35499f3bedSPekka Enberg 	return self->ops->read_sector(self, sector, dst, dst_len);
36499f3bedSPekka Enberg }
37499f3bedSPekka Enberg 
38*3fdf659dSSasha Levin static inline int disk_image__write_sector(struct disk_image *self, u64 sector, void *src, u32 src_len)
39499f3bedSPekka Enberg {
40499f3bedSPekka Enberg 	return self->ops->write_sector(self, sector, src, src_len);
41499f3bedSPekka Enberg }
429f532d00SPekka Enberg 
43*3fdf659dSSasha Levin static inline ssize_t disk_image__read_sector_iov(struct disk_image *self, u64 sector, const struct iovec *iov, int iovcount)
4470b53f25SSasha Levin {
452d103098SSasha Levin 	if (self->ops->read_sector_iov)
462d103098SSasha Levin 		return self->ops->read_sector_iov(self, sector, iov, iovcount);
4770b53f25SSasha Levin 
4870b53f25SSasha Levin 	while (iovcount--) {
4970b53f25SSasha Levin 		self->ops->read_sector(self, sector, iov->iov_base, iov->iov_len);
5070b53f25SSasha Levin 		sector += iov->iov_len >> SECTOR_SHIFT;
5170b53f25SSasha Levin 		iov++;
5270b53f25SSasha Levin 	}
5370b53f25SSasha Levin 
5470b53f25SSasha Levin 	return sector << SECTOR_SHIFT;
5570b53f25SSasha Levin }
5670b53f25SSasha Levin 
57*3fdf659dSSasha Levin static inline ssize_t disk_image__write_sector_iov(struct disk_image *self, u64 sector, const struct iovec *iov, int iovcount)
5870b53f25SSasha Levin {
592d103098SSasha Levin 	if (self->ops->write_sector_iov)
602d103098SSasha Levin 		return self->ops->write_sector_iov(self, sector, iov, iovcount);
6170b53f25SSasha Levin 
6270b53f25SSasha Levin 	while (iovcount--) {
6370b53f25SSasha Levin 		self->ops->write_sector(self, sector, iov->iov_base, iov->iov_len);
6470b53f25SSasha Levin 		sector += iov->iov_len >> SECTOR_SHIFT;
6570b53f25SSasha Levin 		iov++;
6670b53f25SSasha Levin 	}
6770b53f25SSasha Levin 
6870b53f25SSasha Levin 	return sector << SECTOR_SHIFT;
6970b53f25SSasha Levin }
7070b53f25SSasha Levin 
719f532d00SPekka Enberg #endif /* KVM__DISK_IMAGE_H */
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