1 #include "kvm/disk-image.h" 2 3 ssize_t raw_image__read_sector_iov(struct disk_image *disk, u64 sector, const struct iovec *iov, int iovcount) 4 { 5 u64 offset = sector << SECTOR_SHIFT; 6 7 return preadv_in_full(disk->fd, iov, iovcount, offset); 8 } 9 10 ssize_t raw_image__write_sector_iov(struct disk_image *disk, u64 sector, const struct iovec *iov, int iovcount) 11 { 12 u64 offset = sector << SECTOR_SHIFT; 13 14 return pwritev_in_full(disk->fd, iov, iovcount, offset); 15 } 16 17 ssize_t raw_image__read_sector_ro_mmap(struct disk_image *disk, u64 sector, void *dst, u32 dst_len) 18 { 19 u64 offset = sector << SECTOR_SHIFT; 20 21 if (offset + dst_len > disk->size) 22 return -1; 23 24 memcpy(dst, disk->priv + offset, dst_len); 25 26 return dst_len; 27 } 28 29 ssize_t raw_image__write_sector_ro_mmap(struct disk_image *disk, u64 sector, void *src, u32 src_len) 30 { 31 u64 offset = sector << SECTOR_SHIFT; 32 33 if (offset + src_len > disk->size) 34 return -1; 35 36 memcpy(disk->priv + offset, src, src_len); 37 38 return src_len; 39 } 40 41 int raw_image__close_ro_mmap(struct disk_image *disk) 42 { 43 int ret = 0; 44 45 if (disk->priv != MAP_FAILED) 46 ret = munmap(disk->priv, disk->size); 47 48 return ret; 49 } 50 51 static struct disk_image_operations raw_image_ops = { 52 .read_sector_iov = raw_image__read_sector_iov, 53 .write_sector_iov = raw_image__write_sector_iov, 54 }; 55 56 static struct disk_image_operations raw_image_ro_mmap_ops = { 57 .read_sector = raw_image__read_sector_ro_mmap, 58 .write_sector = raw_image__write_sector_ro_mmap, 59 .close = raw_image__close_ro_mmap, 60 }; 61 62 struct disk_image *raw_image__probe(int fd, struct stat *st, bool readonly) 63 { 64 65 if (readonly) 66 /* 67 * Use mmap's MAP_PRIVATE to implement non-persistent write 68 * FIXME: This does not work on 32-bit host. 69 */ 70 return disk_image__new(fd, st->st_size, &raw_image_ro_mmap_ops, DISK_IMAGE_MMAP); 71 else 72 /* 73 * Use read/write instead of mmap 74 */ 75 return disk_image__new(fd, st->st_size, &raw_image_ops, DISK_IMAGE_NOMMAP); 76 } 77