static int
vhd_journal_write_header(vhd_journal_t *j, vhd_journal_header_t *header)
{
int err;
size_t size;
vhd_journal_header_t h;
memcpy(&h, header, sizeof(vhd_journal_header_t));
err = vhd_journal_validate_header(j, &h);
if (err)
return err;
vhd_journal_header_out(&h);
size = sizeof(vhd_journal_header_t);
err = vhd_journal_seek(j, 0, SEEK_SET);
if (err)
return err;
err = vhd_journal_write(j, &h, size);
if (err)
return err;
return 0;
}
static int
vhd_journal_validate_header(vhd_journal_t *j, vhd_journal_header_t *header)
{
int err;
off64_t eof;
if (memcmp(header->cookie,
VHD_JOURNAL_HEADER_COOKIE, sizeof(header->cookie)))
return -EINVAL;
err = vhd_journal_seek(j, j->header.journal_eof, SEEK_SET);
if (err)
return err;
eof = vhd_journal_position(j);
if (eof == (off64_t)-1)
return -errno;
if (j->header.journal_data_offset > j->header.journal_eof)
return -EINVAL;
if (j->header.journal_metadata_offset > j->header.journal_eof)
return -EINVAL;
return 0;
}
static int
vhd_journal_update(vhd_journal_t *j, off_t offset,
char *buf, size_t size, uint32_t type)
{
int err;
off_t eof;
uint64_t *off, off_bak;
uint32_t *entries;
vhd_journal_entry_t entry;
entry.type = type;
entry.size = size;
entry.offset = offset;
entry.cookie = VHD_JOURNAL_ENTRY_COOKIE;
entry.checksum = vhd_journal_checksum_entry(&entry, buf, size);
err = vhd_journal_seek(j, j->header.journal_eof, SEEK_SET);
if (err)
return err;
err = vhd_journal_write_entry(j, &entry);
if (err)
goto fail;
err = vhd_journal_write(j, buf, size);
if (err)
goto fail;
if (type == VHD_JOURNAL_ENTRY_TYPE_DATA) {
off = &j->header.journal_data_offset;
entries = &j->header.journal_data_entries;
} else {
off = &j->header.journal_metadata_offset;
entries = &j->header.journal_metadata_entries;
}
off_bak = *off;
if (!(*entries)++)
*off = j->header.journal_eof;
j->header.journal_eof += (size + sizeof(vhd_journal_entry_t));
err = vhd_journal_write_header(j, &j->header);
if (err) {
if (!--(*entries))
*off = off_bak;
j->header.journal_eof -= (size + sizeof(vhd_journal_entry_t));
goto fail;
}
return 0;
fail:
if (!j->is_block)
vhd_journal_truncate(j, j->header.journal_eof);
return err;
}
static int
vhd_journal_read_journal_header(vhd_journal_t *j, vhd_journal_header_t *header)
{
int err;
size_t size;
size = sizeof(vhd_journal_header_t);
err = vhd_journal_seek(j, 0, SEEK_SET);
if (err)
return err;
err = vhd_journal_read(j, header, size);
if (err)
return err;
vhd_journal_header_in(header);
return vhd_journal_validate_header(j, header);
}
static int
vhd_journal_restore_metadata(vhd_journal_t *j)
{
off64_t off;
char **locators;
vhd_footer_t copy;
vhd_context_t *vhd;
int i, locs, hlocs, err;
vhd = &j->vhd;
locs = 0;
hlocs = 0;
locators = NULL;
err = vhd_journal_seek(j, sizeof(vhd_journal_header_t), SEEK_SET);
if (err)
return err;
err = vhd_journal_read_footer(j, &vhd->footer);
if (err)
return err;
if (!vhd_type_dynamic(vhd))
goto restore;
err = vhd_journal_read_footer_copy(j, ©);
if (err)
return err;
err = vhd_journal_read_header(j, &vhd->header);
if (err)
return err;
for (hlocs = 0, i = 0; i < vhd_parent_locator_count(vhd); i++) {
if (vhd_validate_platform_code(vhd->header.loc[i].code))
return err;
if (vhd->header.loc[i].code != PLAT_CODE_NONE)
hlocs++;
}
if (hlocs) {
err = vhd_journal_read_locators(j, &locators, &locs);
if (err)
return err;
if (hlocs != locs) {
err = -EINVAL;
goto out;
}
}
err = vhd_journal_read_bat(j, &vhd->bat);
if (err)
goto out;
if (vhd_has_batmap(vhd)) {
err = vhd_journal_read_batmap(j, &vhd->batmap);
if (err)
goto out;
}
restore:
off = vhd_journal_position(j);
if (off == (off64_t)-1)
return -errno;
if (j->header.journal_data_offset != off)
return -EINVAL;
err = vhd_journal_restore_footer(j, &vhd->footer);
if (err)
goto out;
if (!vhd_type_dynamic(vhd))
goto out;
err = vhd_journal_restore_footer_copy(j, ©);
if (err)
goto out;
err = vhd_journal_restore_header(j, &vhd->header);
if (err)
goto out;
if (locs) {
err = vhd_journal_restore_locators(j, locators, locs);
if (err)
goto out;
}
err = vhd_journal_restore_bat(j, &vhd->bat);
if (err)
goto out;
if (vhd_has_batmap(vhd)) {
err = vhd_journal_restore_batmap(j, &vhd->batmap);
if (err)
goto out;
}
err = 0;
out:
if (locators) {
for (i = 0; i < locs; i++)
free(locators[i]);
free(locators);
}
if (!err && !vhd->is_block)
err = ftruncate(vhd->fd,
j->header.vhd_footer_offset +
sizeof(vhd_footer_t));
return err;
}
static int
vhd_journal_read_locators(vhd_journal_t *j, char ***locators, int *locs)
{
int err, n, _locs;
char **_locators;
void *buf;
off_t pos;
vhd_journal_entry_t entry;
_locs = 0;
*locs = 0;
*locators = NULL;
n = sizeof(j->vhd.header.loc) / sizeof(vhd_parent_locator_t);
_locators = calloc(n, sizeof(char *));
if (!_locators)
return -ENOMEM;
for (;;) {
buf = NULL;
pos = vhd_journal_position(j);
err = vhd_journal_read_entry(j, &entry);
if (err)
goto fail;
if (entry.type != VHD_JOURNAL_ENTRY_TYPE_LOCATOR) {
err = vhd_journal_seek(j, pos, SEEK_SET);
if (err)
goto fail;
break;
}
if (_locs >= n) {
err = -EINVAL;
goto fail;
}
err = posix_memalign(&buf, VHD_SECTOR_SIZE, entry.size);
if (err) {
err = -err;
buf = NULL;
goto fail;
}
err = vhd_journal_read(j, buf, entry.size);
if (err)
goto fail;
_locators[_locs++] = buf;
err = 0;
}
*locs = _locs;
*locators = _locators;
return 0;
fail:
if (_locators) {
for (n = 0; n < _locs; n++)
free(_locators[n]);
free(_locators);
}
return err;
}
/*
* revert indicates the transaction failed
* and we should revert any changes via the undo log
*/
int
vhd_journal_revert(vhd_journal_t *j)
{
int i, err;
char *file;
void *buf;
vhd_context_t *vhd;
vhd_journal_entry_t entry;
err = 0;
vhd = &j->vhd;
buf = NULL;
file = strdup(vhd->file);
if (!file)
return -ENOMEM;
vhd_close(&j->vhd);
j->vhd.fd = open(file, O_RDWR | O_DIRECT | O_LARGEFILE);
if (j->vhd.fd == -1) {
free(file);
return -errno;
}
err = vhd_test_file_fixed(file, &vhd->is_block);
if (err) {
free(file);
return err;
}
err = vhd_journal_restore_metadata(j);
if (err) {
free(file);
return err;
}
close(vhd->fd);
free(vhd->bat.bat);
free(vhd->batmap.map);
err = vhd_open(vhd, file, VHD_OPEN_RDWR);
free(file);
if (err)
return err;
err = vhd_journal_seek(j, j->header.journal_data_offset, SEEK_SET);
if (err)
return err;
for (i = 0; i < j->header.journal_data_entries; i++) {
err = vhd_journal_read_entry(j, &entry);
if (err)
goto end;
err = posix_memalign(&buf, VHD_SECTOR_SIZE, entry.size);
if (err) {
err = -err;
buf = NULL;
goto end;
}
err = vhd_journal_read(j, buf, entry.size);
if (err)
goto end;
err = vhd_journal_validate_entry_data(&entry, buf);
if (err)
goto end;
err = vhd_seek(vhd, entry.offset, SEEK_SET);
if (err)
goto end;
err = vhd_write(vhd, buf, entry.size);
if (err)
goto end;
err = 0;
end:
free(buf);
buf = NULL;
if (err)
break;
}
if (err)
return err;
if (!vhd->is_block) {
err = ftruncate(vhd->fd, j->header.vhd_footer_offset +
sizeof(vhd_footer_t));
if (err)
return -errno;
}
return vhd_journal_sync(j);
}