int config_file_read(struct dm_config_tree *cft)
{
const char *filename = NULL;
struct config_file *cf = dm_config_get_custom(cft);
struct stat info;
int r;
if (!config_file_check(cft, &filename, &info))
return_0;
/* Nothing to do. E.g. empty file. */
if (!filename)
return 1;
if (!cf->dev) {
if (!(cf->dev = dev_create_file(filename, NULL, NULL, 1)))
return_0;
if (!dev_open_readonly_buffered(cf->dev))
return_0;
}
r = config_file_read_fd(cft, cf->dev, 0, (size_t) info.st_size, 0, 0,
(checksum_fn_t) NULL, 0);
if (!cf->keep_open) {
if (!dev_close(cf->dev))
stack;
cf->dev = NULL;
}
return r;
}
struct volume_group *text_vg_import_fd(struct format_instance *fid,
const char *file,
int single_device,
struct device *dev,
off_t offset, uint32_t size,
off_t offset2, uint32_t size2,
checksum_fn_t checksum_fn,
uint32_t checksum,
time_t *when, char **desc)
{
struct volume_group *vg = NULL;
struct dm_config_tree *cft;
struct text_vg_version_ops **vsn;
_init_text_import();
*desc = NULL;
*when = 0;
if (!(cft = config_open(CONFIG_FILE, file, 0)))
return_NULL;
if ((!dev && !config_file_read(cft)) ||
(dev && !config_file_read_fd(cft, dev, offset, size,
offset2, size2, checksum_fn, checksum))) {
log_error("Couldn't read volume group metadata.");
goto out;
}
/*
* Find a set of version functions that can read this file
*/
for (vsn = &_text_vsn_list[0]; *vsn; vsn++) {
if (!(*vsn)->check_version(cft))
continue;
if (!(vg = (*vsn)->read_vg(fid, cft, single_device)))
goto_out;
(*vsn)->read_desc(vg->vgmem, cft, when, desc);
break;
}
out:
config_destroy(cft);
return vg;
}
const char *text_vgname_import(const struct format_type *fmt,
struct device *dev,
off_t offset, uint32_t size,
off_t offset2, uint32_t size2,
checksum_fn_t checksum_fn, uint32_t checksum,
struct id *vgid, uint64_t *vgstatus,
char **creation_host)
{
struct dm_config_tree *cft;
struct text_vg_version_ops **vsn;
const char *vgname = NULL;
_init_text_import();
if (!(cft = config_open(CONFIG_FILE, NULL, 0)))
return_NULL;
if ((!dev && !config_file_read(cft)) ||
(dev && !config_file_read_fd(cft, dev, offset, size,
offset2, size2, checksum_fn, checksum)))
goto_out;
/*
* Find a set of version functions that can read this file
*/
for (vsn = &_text_vsn_list[0]; *vsn; vsn++) {
if (!(*vsn)->check_version(cft))
continue;
if (!(vgname = (*vsn)->read_vgname(fmt, cft, vgid, vgstatus,
creation_host)))
goto_out;
break;
}
out:
config_destroy(cft);
return vgname;
}
/*
* Find out vgname on a given device.
*/
int text_read_metadata_summary(const struct format_type *fmt,
struct device *dev, dev_io_reason_t reason,
off_t offset, uint32_t size,
off_t offset2, uint32_t size2,
checksum_fn_t checksum_fn,
int checksum_only,
struct lvmcache_vgsummary *vgsummary)
{
struct dm_config_tree *cft;
struct text_vg_version_ops **vsn;
int r = 0;
_init_text_import();
if (!(cft = config_open(CONFIG_FILE_SPECIAL, NULL, 0)))
return_0;
if (dev) {
log_debug_metadata("Reading metadata summary from %s at %llu size %d (+%d)",
dev_name(dev), (unsigned long long)offset,
size, size2);
if (!config_file_read_fd(cft, dev, reason, offset, size,
offset2, size2, checksum_fn,
vgsummary->mda_checksum,
checksum_only, 1)) {
/* FIXME: handle errors */
log_error("Couldn't read volume group metadata from %s.", dev_name(dev));
goto out;
}
} else {
if (!config_file_read(cft)) {
log_error("Couldn't read volume group metadata from file.");
goto out;
}
}
if (checksum_only) {
/* Checksum matches already-cached content - no need to reparse. */
log_debug_metadata("Skipped parsing metadata on %s", dev_name(dev));
r = 1;
goto out;
}
/*
* Find a set of version functions that can read this file
*/
for (vsn = &_text_vsn_list[0]; *vsn; vsn++) {
if (!(*vsn)->check_version(cft))
continue;
if (!(*vsn)->read_vgsummary(fmt, cft, vgsummary))
goto_out;
r = 1;
break;
}
out:
config_destroy(cft);
return r;
}
struct volume_group *text_read_metadata(struct format_instance *fid,
const char *file,
struct cached_vg_fmtdata **vg_fmtdata,
unsigned *use_previous_vg,
struct device *dev, int primary_mda,
off_t offset, uint32_t size,
off_t offset2, uint32_t size2,
checksum_fn_t checksum_fn,
uint32_t checksum,
time_t *when, char **desc)
{
struct volume_group *vg = NULL;
struct dm_config_tree *cft;
struct text_vg_version_ops **vsn;
int skip_parse;
/*
* This struct holds the checksum and size of the VG metadata
* that was read from a previous device. When we read the VG
* metadata from this device, we can skip parsing it into a
* cft (saving time) if the checksum of the metadata buffer
* we read from this device matches the size/checksum saved in
* the mda_header/rlocn struct on this device, and matches the
* size/checksum from the previous device.
*/
if (vg_fmtdata && !*vg_fmtdata &&
!(*vg_fmtdata = dm_pool_zalloc(fid->mem, sizeof(**vg_fmtdata)))) {
log_error("Failed to allocate VG fmtdata for text format.");
return NULL;
}
_init_text_import();
*desc = NULL;
*when = 0;
if (!(cft = config_open(CONFIG_FILE_SPECIAL, file, 0)))
return_NULL;
/* Does the metadata match the already-cached VG? */
skip_parse = vg_fmtdata &&
((*vg_fmtdata)->cached_mda_checksum == checksum) &&
((*vg_fmtdata)->cached_mda_size == (size + size2));
if (dev) {
log_debug_metadata("Reading metadata from %s at %llu size %d (+%d)",
dev_name(dev), (unsigned long long)offset,
size, size2);
if (!config_file_read_fd(cft, dev, MDA_CONTENT_REASON(primary_mda), offset, size,
offset2, size2, checksum_fn, checksum,
skip_parse, 1)) {
/* FIXME: handle errors */
log_error("Couldn't read volume group metadata from %s.", dev_name(dev));
goto out;
}
} else {
if (!config_file_read(cft)) {
log_error("Couldn't read volume group metadata from file.");
goto out;
}
}
if (skip_parse) {
if (use_previous_vg)
*use_previous_vg = 1;
log_debug_metadata("Skipped parsing metadata on %s", dev_name(dev));
goto out;
}
/*
* Find a set of version functions that can read this file
*/
for (vsn = &_text_vsn_list[0]; *vsn; vsn++) {
if (!(*vsn)->check_version(cft))
continue;
if (!(vg = (*vsn)->read_vg(fid, cft, 0)))
goto_out;
(*vsn)->read_desc(vg->vgmem, cft, when, desc);
break;
}
if (vg && vg_fmtdata && *vg_fmtdata) {
(*vg_fmtdata)->cached_mda_size = (size + size2);
(*vg_fmtdata)->cached_mda_checksum = checksum;
}
if (use_previous_vg)
*use_previous_vg = 0;
out:
config_destroy(cft);
return vg;
}
