1 #include "kvm/disk-image.h"
4 struct disk_image *disk_image__new(int fd, u64 size, struct disk_image_operations *ops, int use_mmap)
6 struct disk_image *disk;
8 disk = malloc(sizeof *disk);
16 if (use_mmap == DISK_IMAGE_MMAP) {
18 * The write to disk image will be discarded
20 disk->priv = mmap(NULL, size, PROT_RW, MAP_PRIVATE | MAP_NORESERVE, fd, 0);
21 if (disk->priv == MAP_FAILED)
28 struct disk_image *disk_image__open(const char *filename, bool readonly)
30 struct disk_image *disk;
34 if (stat(filename, &st) < 0)
38 disk = blkdev__probe(filename, &st);
42 fd = open(filename, readonly ? O_RDONLY : O_RDWR);
47 disk = qcow_probe(fd, readonly);
52 disk = raw_image__probe(fd, &st, readonly);
57 pr_warning("close() failed");
62 struct disk_image **disk_image__open_all(const char **filenames, bool *readonly, int count)
64 struct disk_image **disks;
67 if (!count || count > MAX_DISK_IMAGES)
70 disks = calloc(count, sizeof(*disks));
74 for (i = 0; i < count; i++) {
78 disks[i] = disk_image__open(filenames[i], readonly[i]);
80 pr_error("Loading disk image '%s' failed", filenames[i]);
86 for (i = 0; i < count; i++)
87 disk_image__close(disks[i]);
93 int disk_image__flush(struct disk_image *disk)
96 return disk->ops->flush(disk);
98 return fsync(disk->fd);
101 int disk_image__close(struct disk_image *disk)
103 /* If there was no disk image then there's nothing to do: */
107 if (disk->ops->close)
108 return disk->ops->close(disk);
110 if (close(disk->fd) < 0)
111 pr_warning("close() failed");
119 * Fill iov with disk data, starting from sector 'sector'.
120 * Return amount of bytes read.
122 ssize_t disk_image__read(struct disk_image *disk, u64 sector, const struct iovec *iov, int iovcount)
127 if (disk->ops->read_sector_iov) {
129 * Try mulitple buffer based operation first
131 total = disk->ops->read_sector_iov(disk, sector, iov, iovcount);
133 pr_info("disk_image__read error: total=%ld\n", (long)total);
136 } else if (disk->ops->read_sector) {
138 * Fallback to single buffer based operation
141 nr = disk->ops->read_sector(disk, sector, iov->iov_base, iov->iov_len);
142 if (nr != (ssize_t)iov->iov_len) {
143 pr_info("disk_image__read error: nr = %ld iov_len=%ld\n", (long)nr, (long)iov->iov_len);
146 sector += iov->iov_len >> SECTOR_SHIFT;
151 die("No disk image operation for read\n");
157 * Write iov to disk, starting from sector 'sector'.
158 * Return amount of bytes written.
160 ssize_t disk_image__write(struct disk_image *disk, u64 sector, const struct iovec *iov, int iovcount)
165 if (disk->ops->write_sector_iov) {
167 * Try writev based operation first
169 total = disk->ops->write_sector_iov(disk, sector, iov, iovcount);
171 pr_info("disk_image__write error: total=%ld\n", (long)total);
174 } else if (disk->ops->write_sector) {
176 * Fallback to single buffer based operation
179 nr = disk->ops->write_sector(disk, sector, iov->iov_base, iov->iov_len);
180 if (nr != (ssize_t)iov->iov_len) {
181 pr_info("disk_image__write error: nr=%ld iov_len=%ld\n", (long)nr, (long)iov->iov_len);
185 sector += iov->iov_len >> SECTOR_SHIFT;
190 die("No disk image operation for read\n");