// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright 2023 Red Hat
*/
#include "index-layout.h"
#include <linux/random.h>
#include "logger.h"
#include "memory-alloc.h"
#include "murmurhash3.h"
#include "numeric.h"
#include "time-utils.h"
#include "config.h"
#include "open-chapter.h"
#include "volume-index.h"
/*
* The UDS layout on storage media is divided into a number of fixed-size regions, the sizes of
* which are computed when the index is created. Every header and region begins on 4K block
* boundary. Save regions are further sub-divided into regions of their own.
*
* Each region has a kind and an instance number. Some kinds only have one instance and therefore
* use RL_SOLE_INSTANCE (-1) as the instance number. The RL_KIND_INDEX used to use instances to
* represent sub-indices; now, however there is only ever one sub-index and therefore one instance.
* The RL_KIND_VOLUME_INDEX uses instances to record which zone is being saved.
*
* Every region header has a type and version.
*
* +-+-+---------+--------+--------+-+
* | | | I N D E X 0 101, 0 | |
* |H|C+---------+--------+--------+S|
* |D|f| Volume | Save | Save |e|
* |R|g| Region | Region | Region |a|
* | | | 201, -1 | 202, 0 | 202, 1 |l|
* +-+-+--------+---------+--------+-+
*
* The header contains the encoded region layout table as well as some index configuration data.
* The sub-index region and its subdivisions are maintained in the same table.
*
* There are two save regions to preserve the old state in case saving the new state is incomplete.
* They are used in alternation. Each save region is further divided into sub-regions.
*
* +-+-----+------+------+-----+-----+
* |H| IPM | MI | MI | | OC |
* |D| | zone | zone | ... | |
* |R| 301 | 302 | 302 | | 303 |
* | | -1 | 0 | 1 | | -1 |
* +-+-----+------+------+-----+-----+
*
* The header contains the encoded region layout table as well as index state data for that save.
* Each save also has a unique nonce.
*/
#define MAGIC_SIZE 32
#define NONCE_INFO_SIZE 32
#define MAX_SAVES 2
enum region_kind {
RL_KIND_EMPTY = 0,
RL_KIND_HEADER = 1,
RL_KIND_CONFIG = 100,
RL_KIND_INDEX = 101,
RL_KIND_SEAL = 102,
RL_KIND_VOLUME = 201,
RL_KIND_SAVE = 202,
RL_KIND_INDEX_PAGE_MAP = 301,
RL_KIND_VOLUME_INDEX = 302,
RL_KIND_OPEN_CHAPTER = 303,
};
/* Some region types are historical and are no longer used. */
enum region_type {
RH_TYPE_FREE = 0, /* unused */
RH_TYPE_SUPER = 1,
RH_TYPE_SAVE = 2,
RH_TYPE_CHECKPOINT = 3, /* unused */
RH_TYPE_UNSAVED = 4,
};
#define RL_SOLE_INSTANCE 65535
/*
* Super block version 2 is the first released version.
*
* Super block version 3 is the normal version used from RHEL 8.2 onwards.
*
* Super block versions 4 through 6 were incremental development versions and
* are not supported.
*
* Super block version 7 is used for volumes which have been reduced in size by one chapter in
* order to make room to prepend LVM metadata to a volume originally created without lvm. This
* allows the index to retain most its deduplication records.
*/
#define SUPER_VERSION_MINIMUM 3
#define SUPER_VERSION_CURRENT 3
#define SUPER_VERSION_MAXIMUM 7
static const u8 LAYOUT_MAGIC[MAGIC_SIZE] = "*ALBIREO*SINGLE*FILE*LAYOUT*001*";
static const u64 REGION_MAGIC = 0x416c6252676e3031; /* 'AlbRgn01' */
struct region_header {
u64 magic;
u64 region_blocks;
u16 type;
/* Currently always version 1 */
u16 version;
u16 region_count;
u16 payload;
};
struct layout_region {
u64 start_block;
u64 block_count;
u32 __unused;
u16 kind;
u16 instance;
};
struct region_table {
size_t encoded_size;
struct region_header header;
struct layout_region regions[];
};
struct index_save_data {
u64 timestamp;
u64 nonce;
/* Currently always version 1 */
u32 version;
u32 unused__;
};
struct index_state_version {
s32 signature;
s32 version_id;
};
static const struct index_state_version INDEX_STATE_VERSION_301 = {
.signature = -1,
.version_id = 301,
};
struct index_state_data301 {
struct index_state_version version;
u64 newest_chapter;
u64 oldest_chapter;
u64 last_save;
u32 unused;
u32 padding;
};
struct index_save_layout {
unsigned int zone_count;
struct layout_region index_save;
struct layout_region header;
struct layout_region index_page_map;
struct layout_region free_space;
struct layout_region volume_index_zones[MAX_ZONES];
struct layout_region open_chapter;
struct index_save_data save_data;
struct index_state_data301 state_data;
};
struct sub_index_layout {
u64 nonce;
struct layout_region sub_index;
struct layout_region volume;
struct index_save_layout *saves;
};
struct super_block_data {
u8 magic_label[MAGIC_SIZE];
u8 nonce_info[NONCE_INFO_SIZE];
u64 nonce;
u32 version;
u32 block_size;
u16 index_count;
u16 max_saves;
/* Padding reflects a blank field on permanent storage */
u8 padding[4];
u64 open_chapter_blocks;
u64 page_map_blocks;
u64 volume_offset;
u64 start_offset;
};
struct index_layout {
struct io_factory *factory;
size_t factory_size;
off_t offset;
struct super_block_data super;
struct layout_region header;
struct layout_region config;
struct sub_index_layout index;
struct layout_region seal;
u64 total_blocks;
};
struct save_layout_sizes {
unsigned int save_count;
size_t block_size;
u64 volume_blocks;
u64 volume_index_blocks;
u64 page_map_blocks;
u64 open_chapter_blocks;
u64 save_blocks;
u64 sub_index_blocks;
u64 total_blocks;
size_t total_size;
};
static inline bool is_converted_super_block(struct super_block_data *super)
{
return super->version == 7;
}
static int __must_check compute_sizes(const struct uds_configuration *config,
struct save_layout_sizes *sls)
{
int result;
struct index_geometry *geometry = config->geometry;
memset(sls, 0, sizeof(*sls));
sls->save_count = MAX_SAVES;
sls->block_size = UDS_BLOCK_SIZE;
sls->volume_blocks = geometry->bytes_per_volume / sls->block_size;
result = uds_compute_volume_index_save_blocks(config, sls->block_size,
&sls->volume_index_blocks);
if (result != UDS_SUCCESS)
return vdo_log_error_strerror(result, "cannot compute index save size");
sls->page_map_blocks =
DIV_ROUND_UP(uds_compute_index_page_map_save_size(geometry),
sls->block_size);
sls->open_chapter_blocks =
DIV_ROUND_UP(uds_compute_saved_open_chapter_size(geometry),
sls->block_size);
sls->save_blocks =
1 + (sls->volume_index_blocks + sls->page_map_blocks + sls->open_chapter_blocks);
sls->sub_index_blocks = sls->volume_blocks + (sls->save_count * sls->save_blocks);
sls->total_blocks = 3 + sls->sub_index_blocks;
sls->total_size = sls->total_blocks * sls->block_size;
return UDS_SUCCESS;
}
int uds_compute_index_size(const struct uds_parameters *parameters, u64 *index_size)
{
int result;
struct uds_configuration *index_config;
struct save_layout_sizes sizes;
if (index_size == NULL) {
vdo_log_error("Missing output size pointer");
return -EINVAL;
}
result = uds_make_configuration(parameters, &index_config);
if (result != UDS_SUCCESS) {
vdo_log_error_strerror(result, "cannot compute index size");
return uds_status_to_errno(result);
}
result = compute_sizes(index_config, &sizes);
uds_free_configuration(index_config);
if (result != UDS_SUCCESS)
return uds_status_to_errno(result);
*index_size = sizes.total_size;
return UDS_SUCCESS;
}
/* Create unique data using the current time and a pseudorandom number. */
static void create_unique_nonce_data(u8 *buffer)
{
ktime_t now = current_time_ns(CLOCK_REALTIME);
u32 rand;
size_t offset = 0;
get_random_bytes(&rand, sizeof(u32));
memcpy(buffer + offset, &now, sizeof(now));
offset += sizeof(now);
memcpy(buffer + offset, &rand, sizeof(rand));
offset += sizeof(rand);
while (offset < NONCE_INFO_SIZE) {
size_t len = min(NONCE_INFO_SIZE - offset, offset);
memcpy(buffer + offset, buffer, len);
offset += len;
}
}
static u64 hash_stuff(u64 start, const void *data, size_t len)
{
u32 seed = start ^ (start >> 27);
u8 hash_buffer[16];
murmurhash3_128(data, len, seed, hash_buffer);
return get_unaligned_le64(hash_buffer + 4);
}
/* Generate a primary nonce from the provided data. */
static u64 generate_primary_nonce(const void *data, size_t len)
{
return hash_stuff(0xa1b1e0fc, data, len);
}
/*
* Deterministically generate a secondary nonce from an existing nonce and some arbitrary data by
* hashing the original nonce and the data to produce a new nonce.
*/
static u64 generate_secondary_nonce(u64 nonce, const void *data, size_t len)
{
return hash_stuff(nonce + 1, data, len);
}
static int __must_check open_layout_reader(struct index_layout *layout,
struct layout_region *lr, off_t offset,
struct buffered_reader **reader_ptr)
{
return uds_make_buffered_reader(layout->factory, lr->start_block + offset,
lr->block_count, reader_ptr);
}
static int open_region_reader(struct index_layout *layout, struct layout_region *region,
struct buffered_reader **reader_ptr)
{
return open_layout_reader(layout, region, -layout->super.start_offset,
reader_ptr);
}
static int __must_check open_layout_writer(struct index_layout *layout,
struct layout_region *lr, off_t offset,
struct buffered_writer **writer_ptr)
{
return uds_make_buffered_writer(layout->factory, lr->start_block + offset,
lr->block_count, writer_ptr);
}
static int open_region_writer(struct index_layout *layout, struct layout_region *region,
struct buffered_writer **writer_ptr)
{
return open_layout_writer(layout, region, -layout->super.start_offset,
writer_ptr);
}
static void generate_super_block_data(struct save_layout_sizes *sls,
struct super_block_data *super)
{
memset(super, 0, sizeof(*super));
memcpy(super->magic_label, LAYOUT_MAGIC, MAGIC_SIZE);
create_unique_nonce_data(super->nonce_info);
super->nonce = generate_primary_nonce(super->nonce_info,
sizeof(super->nonce_info));
super->version = SUPER_VERSION_CURRENT;
super->block_size = sls->block_size;
super->index_count = 1;
super->max_saves = sls->save_count;
super->open_chapter_blocks = sls->open_chapter_blocks;
super->page_map_blocks = sls->page_map_blocks;
super->volume_offset = 0;
super->start_offset = 0;
}
static void define_sub_index_nonce(struct index_layout *layout)
{
struct sub_index_nonce_data {
u64 offset;
u16 index_id;
};
struct sub_index_layout *sil = &layout->index;
u64 primary_nonce = layout->super.nonce;
u8 buffer[sizeof(struct sub_index_nonce_data)] = { 0 };
size_t offset = 0;
encode_u64_le(buffer, &offset, sil->sub_index.start_block);
encode_u16_le(buffer, &offset, 0);
sil->nonce = generate_secondary_nonce(primary_nonce, buffer, sizeof(buffer));
if (sil->nonce == 0) {
sil->nonce = generate_secondary_nonce(~primary_nonce + 1, buffer,
sizeof(buffer));
}
}
static void setup_sub_index(struct index_layout *layout, u64 start_block,
struct save_layout_sizes *sls)
{
struct sub_index_layout *sil = &layout->index;
u64 next_block = start_block;
unsigned int i;
sil->sub_index = (struct layout_region) {
.start_block = start_block,
.block_count = sls->sub_index_blocks,
.kind = RL_KIND_INDEX,
.instance = 0,
};
sil->volume = (struct layout_region) {
.start_block = next_block,
.block_count = sls->volume_blocks,
.kind = RL_KIND_VOLUME,
.instance = RL_SOLE_INSTANCE,
};
next_block += sls->volume_blocks;
for (i = 0; i < sls->save_count; i++) {
sil->saves[i].index_save = (struct layout_region) {
.start_block = next_block,
.block_count = sls->save_blocks,
.kind = RL_KIND_SAVE,
.instance = i,
};
next_block += sls->save_blocks;
}
define_sub_index_nonce(layout);
}
static void initialize_layout(struct index_layout *layout, struct save_layout_sizes *sls)
{
u64 next_block = layout->offset / sls->block_size;
layout->total_blocks = sls->total_blocks;
generate_super_block_data(sls, &layout->super);
layout->header = (struct layout_region) {
.start_block = next_block++,
.block_count = 1,
.kind = RL_KIND_HEADER,
.instance = RL_SOLE_INSTANCE,
};
layout->config = (struct layout_region) {
.start_block = next_block++,
.block_count = 1,
.kind = RL_KIND_CONFIG,
.instance = RL_SOLE_INSTANCE,
};
setup_sub_index(layout, next_block, sls);
next_block += sls->sub_index_blocks;
layout->seal = (struct layout_region) {
.start_block = next_block,
.block_count = 1,
.kind = RL_KIND_SEAL,
.instance = RL_SOLE_INSTANCE,
};
}
static int __must_check make_index_save_region_table(struct index_save_layout *isl,
struct region_table **table_ptr)
{
int result;
unsigned int z;
struct region_table *table;
struct layout_region *lr;
u16 region_count;
size_t payload;
size_t type;
if (isl->zone_count > 0) {
/*
* Normal save regions: header, page map, volume index zones,
* open chapter, and possibly free space.
*/
region_count = 3 + isl->zone_count;
if (isl->free_space.block_count > 0)
region_count++;
payload = sizeof(isl->save_data) + sizeof(isl->state_data);
type = RH_TYPE_SAVE;
} else {
/* Empty save regions: header, page map, free space. */
region_count = 3;
payload = sizeof(isl->save_data);
type = RH_TYPE_UNSAVED;
}
result = vdo_allocate_extended(struct region_table, region_count,
struct layout_region,
"layout region table for ISL", &table);
if (result != VDO_SUCCESS)
return result;
lr = &table->regions[0];
*lr++ = isl->header;
*lr++ = isl->index_page_map;
for (z = 0; z < isl->zone_count; z++)
*lr++ = isl->volume_index_zones[z];
if (isl->zone_count > 0)
*lr++ = isl->open_chapter;
if (isl->free_space.block_count > 0)
*lr++ = isl->free_space;
table->header = (struct region_header) {
.magic = REGION_MAGIC,
.region_blocks = isl->index_save.block_count,
.type = type,
.version = 1,
.region_count = region_count,
.payload = payload,
};
table->encoded_size = (sizeof(struct region_header) + payload +
region_count * sizeof(struct layout_region));
*table_ptr = table;
return UDS_SUCCESS;
}
static void encode_region_table(u8 *buffer, size_t *offset, struct region_table *table)
{
unsigned int i;
encode_u64_le(buffer, offset, REGION_MAGIC);
encode_u64_le(buffer, offset, table->header.region_blocks);
encode_u16_le(buffer, offset, table->header.type);
encode_u16_le(buffer, offset, table->header.version);
encode_u16_le(buffer, offset, table->header.region_count);
encode_u16_le(buffer, offset, table->header.payload);
for (i = 0; i < table->header.region_count; i++) {
encode_u64_le(buffer, offset, table->regions[i].start_block);
encode_u64_le(buffer, offset, table->regions[i].block_count);
encode_u32_le(buffer, offset, 0);
encode_u16_le(buffer, offset, table->regions[i].kind);
encode_u16_le(buffer, offset, table->regions[i].instance);
}
}
static int __must_check write_index_save_header(struct index_save_layout *isl,
struct region_table *table,
struct buffered_writer *writer)
{
int result;
u8 *buffer;
size_t offset = 0;
result = vdo_allocate(table->encoded_size, u8, "index save data", &buffer);
if (result != VDO_SUCCESS)
return result;
encode_region_table(buffer, &offset, table);
encode_u64_le(buffer, &offset, isl->save_data.timestamp);
encode_u64_le(buffer, &offset, isl->save_data.nonce);
encode_u32_le(buffer, &offset, isl->save_data.version);
encode_u32_le(buffer, &offset, 0);
if (isl->zone_count > 0) {
encode_u32_le(buffer, &offset, INDEX_STATE_VERSION_301.signature);
encode_u32_le(buffer, &offset, INDEX_STATE_VERSION_301.version_id);
encode_u64_le(buffer, &offset, isl->state_data.newest_chapter);
encode_u64_le(buffer, &offset, isl->state_data.oldest_chapter);
encode_u64_le(buffer, &offset, isl->state_data.last_save);
encode_u64_le(buffer, &offset, 0);
}
result = uds_write_to_buffered_writer(writer, buffer, offset);
vdo_free(buffer);
if (result != UDS_SUCCESS)
return result;
return uds_flush_buffered_writer(writer);
}
static int write_index_save_layout(struct index_layout *layout,
struct index_save_layout *isl)
{
int result;
struct region_table *table;
struct buffered_writer *writer;
result = make_index_save_region_table(isl, &table);
if (result != UDS_SUCCESS)
return result;
result = open_region_writer(layout, &isl->header, &writer);
if (result != UDS_SUCCESS) {
vdo_free(table);
return result;
}
result = write_index_save_header(isl, table, writer);
vdo_free(table);
uds_free_buffered_writer(writer);
return result;
}
static void reset_index_save_layout(struct index_save_layout *isl, u64 page_map_blocks)
{
u64 free_blocks;
u64 next_block = isl->index_save.start_block;
isl->zone_count = 0;
memset(&isl->save_data, 0, sizeof(isl->save_data));
isl->header = (struct layout_region) {
.start_block = next_block++,
.block_count = 1,
.kind = RL_KIND_HEADER,
.instance = RL_SOLE_INSTANCE,
};
isl->index_page_map = (struct layout_region) {
.start_block = next_block,
.block_count = page_map_blocks,
.kind = RL_KIND_INDEX_PAGE_MAP,
.instance = RL_SOLE_INSTANCE,
};
next_block += page_map_blocks;
free_blocks = isl->index_save.block_count - page_map_blocks - 1;
isl->free_space = (struct layout_region) {
.start_block = next_block,
.block_count = free_blocks,
.kind = RL_KIND_EMPTY,
.instance = RL_SOLE_INSTANCE,
};
}
static int __must_check invalidate_old_save(struct index_layout *layout,
struct index_save_layout *isl)
{
reset_index_save_layout(isl, layout->super.page_map_blocks);
return write_index_save_layout(layout, isl);
}
static int discard_index_state_data(struct index_layout *layout)
{
int result;
int saved_result = UDS_SUCCESS;
unsigned int i;
for (i = 0; i < layout->super.max_saves; i++) {
result = invalidate_old_save(layout, &layout->index.saves[i]);
if (result != UDS_SUCCESS)
saved_result = result;
}
if (saved_result != UDS_SUCCESS) {
return vdo_log_error_strerror(result,
"%s: cannot destroy all index saves",
__func__);
}
return UDS_SUCCESS;
}
static int __must_check make_layout_region_table(struct index_layout *layout,
struct region_table **table_ptr)
{
int result;
unsigned int i;
/* Regions: header, config, index, volume, saves, seal */
u16 region_count = 5 + layout->super.max_saves;
u16 payload;
struct region_table *table;
struct layout_region *lr;
result = vdo_allocate_extended(struct region_table, region_count,
struct layout_region, "layout region table",
&table);
if (result != VDO_SUCCESS)
return result;
lr = &table->regions[0];
*lr++ = layout->header;
*lr++ = layout->config;
*lr++ = layout->index.sub_index;
*lr++ = layout->index.volume;
for (i = 0; i < layout->super.max_saves; i++)
*lr++ = layout->index.saves[i].index_save;
*lr++ = layout->seal;
if (is_converted_super_block(&layout->super)) {
payload = sizeof(struct super_block_data);
} else {
payload = (sizeof(struct super_block_data) -
sizeof(layout->super.volume_offset) -
sizeof(layout->super.start_offset));
}
table->header = (struct region_header) {
.magic = REGION_MAGIC,
.region_blocks = layout->total_blocks,
.type = RH_TYPE_SUPER,
.version = 1,
.region_count = region_count,
.payload = payload,
};
table->encoded_size = (sizeof(struct region_header) + payload +
region_count * sizeof(struct layout_region));
*table_ptr = table;
return UDS_SUCCESS;
}
static int __must_check write_layout_header(struct index_layout *layout,
struct region_table *table,
struct buffered_writer *writer)
{
int result;
u8 *buffer;
size_t offset = 0;
result = vdo_allocate(table->encoded_size, u8, "layout data", &buffer);
if (result != VDO_SUCCESS)
return result;
encode_region_table(buffer, &offset, table);
memcpy(buffer + offset, &layout->super.magic_label, MAGIC_SIZE);
offset += MAGIC_SIZE;
memcpy(buffer + offset, &layout->super.nonce_info, NONCE_INFO_SIZE);
offset += NONCE_INFO_SIZE;
encode_u64_le(buffer, &offset, layout->super.nonce);
encode_u32_le(buffer, &offset, layout->super.version);
encode_u32_le(buffer, &offset, layout->super.block_size);
encode_u16_le(buffer, &offset, layout->super.index_count);
encode_u16_le(buffer, &offset, layout->super.max_saves);
encode_u32_le(buffer, &offset, 0);
encode_u64_le(buffer, &offset, layout->super.open_chapter_blocks);
encode_u64_le(buffer, &offset, layout->super.page_map_blocks);
if (is_converted_super_block(&layout->super)) {
encode_u64_le(buffer, &offset, layout->super.volume_offset);
encode_u64_le(buffer, &offset, layout->super.start_offset);
}
result = uds_write_to_buffered_writer(writer, buffer, offset);
vdo_free(buffer);
if (result != UDS_SUCCESS)
return result;
return uds_flush_buffered_writer(writer);
}
static int __must_check write_uds_index_config(struct index_layout *layout,
struct uds_configuration *config,
off_t offset)
{
int result;
struct buffered_writer *writer = NULL;
result = open_layout_writer(layout, &layout->config, offset, &writer);
if (result != UDS_SUCCESS)
return vdo_log_error_strerror(result, "failed to open config region");
result = uds_write_config_contents(writer, config, layout->super.version);
if (result != UDS_SUCCESS) {
uds_free_buffered_writer(writer);
return vdo_log_error_strerror(result, "failed to write config region");
}
result = uds_flush_buffered_writer(writer);
if (result != UDS_SUCCESS) {
uds_free_buffered_writer(writer);
return vdo_log_error_strerror(result, "cannot flush config writer");
}
uds_free_buffered_writer(writer);
return UDS_SUCCESS;
}
static int __must_check save_layout(struct index_layout *layout, off_t offset)
{
int result;
struct buffered_writer *writer = NULL;
struct region_table *table;
result = make_layout_region_table(layout, &table);
if (result != UDS_SUCCESS)
return result;
result = open_layout_writer(layout, &layout->header, offset, &writer);
if (result != UDS_SUCCESS) {
vdo_free(table);
return result;
}
result = write_layout_header(layout, table, writer);
vdo_free(table);
uds_free_buffered_writer(writer);
return result;
}
static int create_index_layout(struct index_layout *layout, struct uds_configuration *config)
{
int result;
struct save_layout_sizes sizes;
result = compute_sizes(config, &sizes);
if (result != UDS_SUCCESS)
return result;
result = vdo_allocate(sizes.save_count, struct index_save_layout, __func__,
&layout->index.saves);
if (result != VDO_SUCCESS)
return result;
initialize_layout(layout, &sizes);
result = discard_index_state_data(layout);
if (result != UDS_SUCCESS)
return result;
result = write_uds_index_config(layout, config, 0);
if (result != UDS_SUCCESS)
return result;
return save_layout(layout, 0);
}
static u64 generate_index_save_nonce(u64 volume_nonce, struct index_save_layout *isl)
{
struct save_nonce_data {
struct index_save_data data;
u64 offset;
} nonce_data;
u8 buffer[sizeof(nonce_data)];
size_t offset = 0;
encode_u64_le(buffer, &offset, isl->save_data.timestamp);
encode_u64_le(buffer, &offset, 0);
encode_u32_le(buffer, &offset, isl->save_data.version);
encode_u32_le(buffer, &offset, 0U);
encode_u64_le(buffer, &offset, isl->index_save.start_block);
VDO_ASSERT_LOG_ONLY(offset == sizeof(nonce_data),
"%zu bytes encoded of %zu expected",
offset, sizeof(nonce_data));
return generate_secondary_nonce(volume_nonce, buffer, sizeof(buffer));
}
static u64 validate_index_save_layout(struct index_save_layout *isl, u64 volume_nonce)
{
if ((isl->zone_count == 0) || (isl->save_data.timestamp == 0))
return 0;
if (isl->save_data.nonce != generate_index_save_nonce(volume_nonce, isl))
return 0;
return isl->save_data.timestamp;
}
static int find_latest_uds_index_save_slot(struct index_layout *layout,
struct index_save_layout **isl_ptr)
{
struct index_save_layout *latest = NULL;
struct index_save_layout *isl;
unsigned int i;
u64 save_time = 0;
u64 latest_time = 0;
for (i = 0; i < layout->super.max_saves; i++) {
isl = &layout->index.saves[i];
save_time = validate_index_save_layout(isl, layout->index.nonce);
if (save_time > latest_time) {
latest = isl;
latest_time = save_time;
}
}
if (latest == NULL) {
vdo_log_error("No valid index save found");
return UDS_INDEX_NOT_SAVED_CLEANLY;
}
*isl_ptr = latest;
return UDS_SUCCESS;
}
int uds_discard_open_chapter(struct index_layout *layout)
{
int result;
struct index_save_layout *isl;
struct buffered_writer *writer;
result = find_latest_uds_index_save_slot(layout, &isl);
if (result != UDS_SUCCESS)
return result;
result = open_region_writer(layout, &isl->open_chapter, &writer);
if (result != UDS_SUCCESS)
return result;
result = uds_write_to_buffered_writer(writer, NULL, UDS_BLOCK_SIZE);
if (result != UDS_SUCCESS) {
uds_free_buffered_writer(writer);
return result;
}
result = uds_flush_buffered_writer(writer);
uds_free_buffered_writer(writer);
return result;
}
int uds_load_index_state(struct index_layout *layout, struct uds_index *index)
{
int result;
unsigned int zone;
struct index_save_layout *isl;
struct buffered_reader *readers[MAX_ZONES];
result = find_latest_uds_index_save_slot(layout, &isl);
if (result != UDS_SUCCESS)
return result;
index->newest_virtual_chapter = isl->state_data.newest_chapter;
index->oldest_virtual_chapter = isl->state_data.oldest_chapter;
index->last_save = isl->state_data.last_save;
result = open_region_reader(layout, &isl->open_chapter, &readers[0]);
if (result != UDS_SUCCESS)
return result;
result = uds_load_open_chapter(index, readers[0]);
uds_free_buffered_reader(readers[0]);
if (result != UDS_SUCCESS)
return result;
for (zone = 0; zone < isl->zone_count; zone++) {
result = open_region_reader(layout, &isl->volume_index_zones[zone],
&readers[zone]);
if (result != UDS_SUCCESS) {
for (; zone > 0; zone--)
uds_free_buffered_reader(readers[zone - 1]);
return result;
}
}
result = uds_load_volume_index(index->volume_index, readers, isl->zone_count);
for (zone = 0; zone < isl->zone_count; zone++)
uds_free_buffered_reader(readers[zone]);
if (result != UDS_SUCCESS)
return result;
result = open_region_reader(layout, &isl->index_page_map, &readers[0]);
if (result != UDS_SUCCESS)
return result;
result = uds_read_index_page_map(index->volume->index_page_map, readers[0]);
uds_free_buffered_reader(readers[0]);
return result;
}
static struct index_save_layout *select_oldest_index_save_layout(struct index_layout *layout)
{
struct index_save_layout *oldest = NULL;
struct index_save_layout *isl;
unsigned int i;
u64 save_time = 0;
u64 oldest_time = 0;
for (i = 0; i < layout->super.max_saves; i++) {
isl = &layout->index.saves[i];
save_time = validate_index_save_layout(isl, layout->index.nonce);
if (oldest == NULL || save_time < oldest_time) {
oldest = isl;
oldest_time = save_time;
}
}
return oldest;
}
static void instantiate_index_save_layout(struct index_save_layout *isl,
struct super_block_data *super,
u64 volume_nonce, unsigned int zone_count)
{
unsigned int z;
u64 next_block;
u64 free_blocks;
u64 volume_index_blocks;
isl->zone_count = zone_count;
memset(&isl->save_data, 0, sizeof(isl->save_data));
isl->save_data.timestamp = ktime_to_ms(current_time_ns(CLOCK_REALTIME));
isl->save_data.version = 1;
isl->save_data.nonce = generate_index_save_nonce(volume_nonce, isl);
next_block = isl->index_save.start_block;
isl->header = (struct layout_region) {
.start_block = next_block++,
.block_count = 1,
.kind = RL_KIND_HEADER,
.instance = RL_SOLE_INSTANCE,
};
isl->index_page_map = (struct layout_region) {
.start_block = next_block,
.block_count = super->page_map_blocks,
.kind = RL_KIND_INDEX_PAGE_MAP,
.instance = RL_SOLE_INSTANCE,
};
next_block += super->page_map_blocks;
free_blocks = (isl->index_save.block_count - 1 -
super->page_map_blocks -
super->open_chapter_blocks);
volume_index_blocks = free_blocks / isl->zone_count;
for (z = 0; z < isl->zone_count; z++) {
isl->volume_index_zones[z] = (struct layout_region) {
.start_block = next_block,
.block_count = volume_index_blocks,
.kind = RL_KIND_VOLUME_INDEX,
.instance = z,
};
next_block += volume_index_blocks;
free_blocks -= volume_index_blocks;
}
isl->open_chapter = (struct layout_region) {
.start_block = next_block,
.block_count = super->open_chapter_blocks,
.kind = RL_KIND_OPEN_CHAPTER,
.instance = RL_SOLE_INSTANCE,
};
next_block += super->open_chapter_blocks;
isl->free_space = (struct layout_region) {
.start_block = next_block,
.block_count = free_blocks,
.kind = RL_KIND_EMPTY,
.instance = RL_SOLE_INSTANCE,
};
}
static int setup_uds_index_save_slot(struct index_layout *layout,
unsigned int zone_count,
struct index_save_layout **isl_ptr)
{
int result;
struct index_save_layout *isl;
isl = select_oldest_index_save_layout(layout);
result = invalidate_old_save(layout, isl);
if (result != UDS_SUCCESS)
return result;
instantiate_index_save_layout(isl, &layout->super, layout->index.nonce,
zone_count);
*isl_ptr = isl;
return UDS_SUCCESS;
}
static void cancel_uds_index_save(struct index_save_layout *isl)
{
memset(&isl->save_data, 0, sizeof(isl->save_data));
memset(&isl->state_data, 0, sizeof(isl->state_data));
isl->zone_count = 0;
}
int uds_save_index_state(struct index_layout *layout, struct uds_index *index)
{
int result;
unsigned int zone;
struct index_save_layout *isl;
struct buffered_writer *writers[MAX_ZONES];
result = setup_uds_index_save_slot(layout, index->zone_count, &isl);
if (result != UDS_SUCCESS)
return result;
isl->state_data = (struct index_state_data301) {
.newest_chapter = index->newest_virtual_chapter,
.oldest_chapter = index->oldest_virtual_chapter,
.last_save = index->last_save,
};
result = open_region_writer(layout, &isl->open_chapter, &writers[0]);
if (result != UDS_SUCCESS) {
cancel_uds_index_save(isl);
return result;
}
result = uds_save_open_chapter(index, writers[0]);
uds_free_buffered_writer(writers[0]);
if (result != UDS_SUCCESS) {
cancel_uds_index_save(isl);
return result;
}
for (zone = 0; zone < index->zone_count; zone++) {
result = open_region_writer(layout, &isl->volume_index_zones[zone],
&writers[zone]);
if (result != UDS_SUCCESS) {
for (; zone > 0; zone--)
uds_free_buffered_writer(writers[zone - 1]);
cancel_uds_index_save(isl);
return result;
}
}
result = uds_save_volume_index(index->volume_index, writers, index->zone_count);
for (zone = 0; zone < index->zone_count; zone++)
uds_free_buffered_writer(writers[zone]);
if (result != UDS_SUCCESS) {
cancel_uds_index_save(isl);
return result;
}
result = open_region_writer(layout, &isl->index_page_map, &writers[0]);
if (result != UDS_SUCCESS) {
cancel_uds_index_save(isl);
return result;
}
result = uds_write_index_page_map(index->volume->index_page_map, writers[0]);
uds_free_buffered_writer(writers[0]);
if (result != UDS_SUCCESS) {
cancel_uds_index_save(isl);
return result;
}
return write_index_save_layout(layout, isl);
}
static int __must_check load_region_table(struct buffered_reader *reader,
struct region_table **table_ptr)
{
int result;
unsigned int i;
struct region_header header;
struct region_table *table;
u8 buffer[sizeof(struct region_header)];
size_t offset = 0;
result = uds_read_from_buffered_reader(reader, buffer, sizeof(buffer));
if (result != UDS_SUCCESS)
return vdo_log_error_strerror(result, "cannot read region table header");
decode_u64_le(buffer, &offset, &header.magic);
decode_u64_le(buffer, &offset, &header.region_blocks);
decode_u16_le(buffer, &offset, &header.type);
decode_u16_le(buffer, &offset, &header.version);
decode_u16_le(buffer, &offset, &header.region_count);
decode_u16_le(buffer, &offset, &header.payload);
if (header.magic != REGION_MAGIC)
return UDS_NO_INDEX;
if (header.version != 1) {
return vdo_log_error_strerror(UDS_UNSUPPORTED_VERSION,
"unknown region table version %hu",
header.version);
}
result = vdo_allocate_extended(struct region_table, header.region_count,
struct layout_region,
"single file layout region table", &table);
if (result != VDO_SUCCESS)
return result;
table->header = header;
for (i = 0; i < header.region_count; i++) {
u8 region_buffer[sizeof(struct layout_region)];
offset = 0;
result = uds_read_from_buffered_reader(reader, region_buffer,
sizeof(region_buffer));
if (result != UDS_SUCCESS) {
vdo_free(table);
return vdo_log_error_strerror(UDS_CORRUPT_DATA,
"cannot read region table layouts");
}
decode_u64_le(region_buffer, &offset, &table->regions[i].start_block);
decode_u64_le(region_buffer, &offset, &table->regions[i].block_count);
offset += sizeof(u32);
decode_u16_le(region_buffer, &offset, &table->regions[i].kind);
decode_u16_le(region_buffer, &offset, &table->regions[i].instance);
}
*table_ptr = table;
return UDS_SUCCESS;
}
static int __must_check read_super_block_data(struct buffered_reader *reader,
struct index_layout *layout,
size_t saved_size)
{
int result;
struct super_block_data *super = &layout->super;
u8 *buffer;
size_t offset = 0;
result = vdo_allocate(saved_size, u8, "super block data", &buffer);
if (result != VDO_SUCCESS)
return result;
result = uds_read_from_buffered_reader(reader, buffer, saved_size);
if (result != UDS_SUCCESS) {
vdo_free(buffer);
return vdo_log_error_strerror(result, "cannot read region table header");
}
memcpy(&super->magic_label, buffer, MAGIC_SIZE);
offset += MAGIC_SIZE;
memcpy(&super->nonce_info, buffer + offset, NONCE_INFO_SIZE);
offset += NONCE_INFO_SIZE;
decode_u64_le(buffer, &offset, &super->nonce);
decode_u32_le(buffer, &offset, &super->version);
decode_u32_le(buffer, &offset, &super->block_size);
decode_u16_le(buffer, &offset, &super->index_count);
decode_u16_le(buffer, &offset, &super->max_saves);
offset += sizeof(u32);
decode_u64_le(buffer, &offset, &super->open_chapter_blocks);
decode_u64_le(buffer, &offset, &super->page_map_blocks);
if (is_converted_super_block(super)) {
decode_u64_le(buffer, &offset, &super->volume_offset);
decode_u64_le(buffer, &offset, &super->start_offset);
} else {
super->volume_offset = 0;
super->start_offset = 0;
}
vdo_free(buffer);
if (memcmp(super->magic_label, LAYOUT_MAGIC, MAGIC_SIZE) != 0)
return vdo_log_error_strerror(UDS_CORRUPT_DATA,
"unknown superblock magic label");
if ((super->version < SUPER_VERSION_MINIMUM) ||
(super->version == 4) || (super->version == 5) || (super->version == 6) ||
(super->version > SUPER_VERSION_MAXIMUM)) {
return vdo_log_error_strerror(UDS_UNSUPPORTED_VERSION,
"unknown superblock version number %u",
super->version);
}
if (super->volume_offset < super->start_offset) {
return vdo_log_error_strerror(UDS_CORRUPT_DATA,
"inconsistent offsets (start %llu, volume %llu)",
(unsigned long long) super->start_offset,
(unsigned long long) super->volume_offset);
}
/* Sub-indexes are no longer used but the layout retains this field. */
if (super->index_count != 1) {
return vdo_log_error_strerror(UDS_CORRUPT_DATA,
"invalid subindex count %u",
super->index_count);
}
if (generate_primary_nonce(super->nonce_info, sizeof(super->nonce_info)) != super->nonce) {
return vdo_log_error_strerror(UDS_CORRUPT_DATA,
"inconsistent superblock nonce");
}
return UDS_SUCCESS;
}
static int __must_check verify_region(struct layout_region *lr, u64 start_block,
enum region_kind kind, unsigned int instance)
{
if (lr->start_block != start_block)
return vdo_log_error_strerror(UDS_CORRUPT_DATA,
"incorrect layout region offset");
if (lr->kind != kind)
return vdo_log_error_strerror(UDS_CORRUPT_DATA,
"incorrect layout region kind");
if (lr->instance != instance) {
return vdo_log_error_strerror(UDS_CORRUPT_DATA,
"incorrect layout region instance");
}
return UDS_SUCCESS;
}
static int __must_check verify_sub_index(struct index_layout *layout, u64 start_block,
struct region_table *table)
{
int result;
unsigned int i;
struct sub_index_layout *sil = &layout->index;
u64 next_block = start_block;
sil->sub_index = table->regions[2];
result = verify_region(&sil->sub_index, next_block, RL_KIND_INDEX, 0);
if (result != UDS_SUCCESS)
return result;
define_sub_index_nonce(layout);
sil->volume = table->regions[3];
result = verify_region(&sil->volume, next_block, RL_KIND_VOLUME,
RL_SOLE_INSTANCE);
if (result != UDS_SUCCESS)
return result;
next_block += sil->volume.block_count + layout->super.volume_offset;
for (i = 0; i < layout->super.max_saves; i++) {
sil->saves[i].index_save = table->regions[i + 4];
result = verify_region(&sil->saves[i].index_save, next_block,
RL_KIND_SAVE, i);
if (result != UDS_SUCCESS)
return result;
next_block += sil->saves[i].index_save.block_count;
}
next_block -= layout->super.volume_offset;
if (next_block != start_block + sil->sub_index.block_count) {
return vdo_log_error_strerror(UDS_CORRUPT_DATA,
"sub index region does not span all saves");
}
return UDS_SUCCESS;
}
static int __must_check reconstitute_layout(struct index_layout *layout,
struct region_table *table, u64 first_block)
{
int result;
u64 next_block = first_block;
result = vdo_allocate(layout->super.max_saves, struct index_save_layout,
__func__, &layout->index.saves);
if (result != VDO_SUCCESS)
return result;
layout->total_blocks = table->header.region_blocks;
layout->header = table->regions[0];
result = verify_region(&layout->header, next_block++, RL_KIND_HEADER,
RL_SOLE_INSTANCE);
if (result != UDS_SUCCESS)
return result;
layout->config = table->regions[1];
result = verify_region(&layout->config, next_block++, RL_KIND_CONFIG,
RL_SOLE_INSTANCE);
if (result != UDS_SUCCESS)
return result;
result = verify_sub_index(layout, next_block, table);
if (result != UDS_SUCCESS)
return result;
next_block += layout->index.sub_index.block_count;
layout->seal = table->regions[table->header.region_count - 1];
result = verify_region(&layout->seal, next_block + layout->super.volume_offset,
RL_KIND_SEAL, RL_SOLE_INSTANCE);
if (result != UDS_SUCCESS)
return result;
if (++next_block != (first_block + layout->total_blocks)) {
return vdo_log_error_strerror(UDS_CORRUPT_DATA,
"layout table does not span total blocks");
}
return UDS_SUCCESS;
}
static int __must_check load_super_block(struct index_layout *layout, size_t block_size,
u64 first_block, struct buffered_reader *reader)
{
int result;
struct region_table *table = NULL;
struct super_block_data *super = &layout->super;
result = load_region_table(reader, &table);
if (result != UDS_SUCCESS)
return result;
if (table->header.type != RH_TYPE_SUPER) {
vdo_free(table);
return vdo_log_error_strerror(UDS_CORRUPT_DATA,
"not a superblock region table");
}
result = read_super_block_data(reader, layout, table->header.payload);
if (result != UDS_SUCCESS) {
vdo_free(table);
return vdo_log_error_strerror(result, "unknown superblock format");
}
if (super->block_size != block_size) {
vdo_free(table);
return vdo_log_error_strerror(UDS_CORRUPT_DATA,
"superblock saved block_size %u differs from supplied block_size %zu",
super->block_size, block_size);
}
first_block -= (super->volume_offset - super->start_offset);
result = reconstitute_layout(layout, table, first_block);
vdo_free(table);
return result;
}
static int __must_check read_index_save_data(struct buffered_reader *reader,
struct index_save_layout *isl,
size_t saved_size)
{
int result;
struct index_state_version file_version;
u8 buffer[sizeof(struct index_save_data) + sizeof(struct index_state_data301)];
size_t offset = 0;
if (saved_size != sizeof(buffer)) {
return vdo_log_error_strerror(UDS_CORRUPT_DATA,
"unexpected index save data size %zu",
saved_size);
}
result = uds_read_from_buffered_reader(reader, buffer, sizeof(buffer));
if (result != UDS_SUCCESS)
return vdo_log_error_strerror(result, "cannot read index save data");
decode_u64_le(buffer, &offset, &isl->save_data.timestamp);
decode_u64_le(buffer, &offset, &isl->save_data.nonce);
decode_u32_le(buffer, &offset, &isl->save_data.version);
offset += sizeof(u32);
if (isl->save_data.version > 1) {
return vdo_log_error_strerror(UDS_UNSUPPORTED_VERSION,
"unknown index save version number %u",
isl->save_data.version);
}
decode_s32_le(buffer, &offset, &file_version.signature);
decode_s32_le(buffer, &offset, &file_version.version_id);
if ((file_version.signature != INDEX_STATE_VERSION_301.signature) ||
(file_version.version_id != INDEX_STATE_VERSION_301.version_id)) {
return vdo_log_error_strerror(UDS_UNSUPPORTED_VERSION,
"index state version %d,%d is unsupported",
file_version.signature,
file_version.version_id);
}
decode_u64_le(buffer, &offset, &isl->state_data.newest_chapter);
decode_u64_le(buffer, &offset, &isl->state_data.oldest_chapter);
decode_u64_le(buffer, &offset, &isl->state_data.last_save);
/* Skip past some historical fields that are now unused */
offset += sizeof(u32) + sizeof(u32);
return UDS_SUCCESS;
}
static int __must_check reconstruct_index_save(struct index_save_layout *isl,
struct region_table *table)
{
int result;
unsigned int z;
struct layout_region *last_region;
u64 next_block = isl->index_save.start_block;
u64 last_block = next_block + isl->index_save.block_count;
isl->zone_count = table->header.region_count - 3;
last_region = &table->regions[table->header.region_count - 1];
if (last_region->kind == RL_KIND_EMPTY) {
isl->free_space = *last_region;
isl->zone_count--;
} else {
isl->free_space = (struct layout_region) {
.start_block = last_block,
.block_count = 0,
.kind = RL_KIND_EMPTY,
.instance = RL_SOLE_INSTANCE,
};
}
isl->header = table->regions[0];
result = verify_region(&isl->header, next_block++, RL_KIND_HEADER,
RL_SOLE_INSTANCE);
if (result != UDS_SUCCESS)
return result;
isl->index_page_map = table->regions[1];
result = verify_region(&isl->index_page_map, next_block, RL_KIND_INDEX_PAGE_MAP,
RL_SOLE_INSTANCE);
if (result != UDS_SUCCESS)
return result;
next_block += isl->index_page_map.block_count;
for (z = 0; z < isl->zone_count; z++) {
isl->volume_index_zones[z] = table->regions[z + 2];
result = verify_region(&isl->volume_index_zones[z], next_block,
RL_KIND_VOLUME_INDEX, z);
if (result != UDS_SUCCESS)
return result;
next_block += isl->volume_index_zones[z].block_count;
}
isl->open_chapter = table->regions[isl->zone_count + 2];
result = verify_region(&isl->open_chapter, next_block, RL_KIND_OPEN_CHAPTER,
RL_SOLE_INSTANCE);
if (result != UDS_SUCCESS)
return result;
next_block += isl->open_chapter.block_count;
result = verify_region(&isl->free_space, next_block, RL_KIND_EMPTY,
RL_SOLE_INSTANCE);
if (result != UDS_SUCCESS)
return result;
next_block += isl->free_space.block_count;
if (next_block != last_block) {
return vdo_log_error_strerror(UDS_CORRUPT_DATA,
"index save layout table incomplete");
}
return UDS_SUCCESS;
}
static int __must_check load_index_save(struct index_save_layout *isl,
struct buffered_reader *reader,
unsigned int instance)
{
int result;
struct region_table *table = NULL;
result = load_region_table(reader, &table);
if (result != UDS_SUCCESS) {
return vdo_log_error_strerror(result, "cannot read index save %u header",
instance);
}
if (table->header.region_blocks != isl->index_save.block_count) {
u64 region_blocks = table->header.region_blocks;
vdo_free(table);
return vdo_log_error_strerror(UDS_CORRUPT_DATA,
"unexpected index save %u region block count %llu",
instance,
(unsigned long long) region_blocks);
}
if (table->header.type == RH_TYPE_UNSAVED) {
vdo_free(table);
reset_index_save_layout(isl, 0);
return UDS_SUCCESS;
}
if (table->header.type != RH_TYPE_SAVE) {
vdo_log_error_strerror(UDS_CORRUPT_DATA,
"unexpected index save %u header type %u",
instance, table->header.type);
vdo_free(table);
return UDS_CORRUPT_DATA;
}
result = read_index_save_data(reader, isl, table->header.payload);
if (result != UDS_SUCCESS) {
vdo_free(table);
return vdo_log_error_strerror(result,
"unknown index save %u data format",
instance);
}
result = reconstruct_index_save(isl, table);
vdo_free(table);
if (result != UDS_SUCCESS) {
return vdo_log_error_strerror(result, "cannot reconstruct index save %u",
instance);
}
return UDS_SUCCESS;
}
static int __must_check load_sub_index_regions(struct index_layout *layout)
{
int result;
unsigned int j;
struct index_save_layout *isl;
struct buffered_reader *reader;
for (j = 0; j < layout->super.max_saves; j++) {
isl = &layout->index.saves[j];
result = open_region_reader(layout, &isl->index_save, &reader);
if (result != UDS_SUCCESS) {
vdo_log_error_strerror(result,
"cannot get reader for index 0 save %u",
j);
return result;
}
result = load_index_save(isl, reader, j);
uds_free_buffered_reader(reader);
if (result != UDS_SUCCESS) {
/* Another save slot might be valid. */
reset_index_save_layout(isl, 0);
continue;
}
}
return UDS_SUCCESS;
}
static int __must_check verify_uds_index_config(struct index_layout *layout,
struct uds_configuration *config)
{
int result;
struct buffered_reader *reader = NULL;
u64 offset;
offset = layout->super.volume_offset - layout->super.start_offset;
result = open_layout_reader(layout, &layout->config, offset, &reader);
if (result != UDS_SUCCESS)
return vdo_log_error_strerror(result, "failed to open config reader");
result = uds_validate_config_contents(reader, config);
if (result != UDS_SUCCESS) {
uds_free_buffered_reader(reader);
return vdo_log_error_strerror(result, "failed to read config region");
}
uds_free_buffered_reader(reader);
return UDS_SUCCESS;
}
static int load_index_layout(struct index_layout *layout, struct uds_configuration *config)
{
int result;
struct buffered_reader *reader;
result = uds_make_buffered_reader(layout->factory,
layout->offset / UDS_BLOCK_SIZE, 1, &reader);
if (result != UDS_SUCCESS)
return vdo_log_error_strerror(result, "unable to read superblock");
result = load_super_block(layout, UDS_BLOCK_SIZE,
layout->offset / UDS_BLOCK_SIZE, reader);
uds_free_buffered_reader(reader);
if (result != UDS_SUCCESS)
return result;
result = verify_uds_index_config(layout, config);
if (result != UDS_SUCCESS)
return result;
return load_sub_index_regions(layout);
}
static int create_layout_factory(struct index_layout *layout,
const struct uds_configuration *config)
{
int result;
size_t writable_size;
struct io_factory *factory = NULL;
result = uds_make_io_factory(config->bdev, &factory);
if (result != UDS_SUCCESS)
return result;
writable_size = uds_get_writable_size(factory) & -UDS_BLOCK_SIZE;
if (writable_size < config->size + config->offset) {
uds_put_io_factory(factory);
vdo_log_error("index storage (%zu) is smaller than the requested size %zu",
writable_size, config->size + config->offset);
return -ENOSPC;
}
layout->factory = factory;
layout->factory_size = (config->size > 0) ? config->size : writable_size;
layout->offset = config->offset;
return UDS_SUCCESS;
}
int uds_make_index_layout(struct uds_configuration *config, bool new_layout,
struct index_layout **layout_ptr)
{
int result;
struct index_layout *layout = NULL;
struct save_layout_sizes sizes;
result = compute_sizes(config, &sizes);
if (result != UDS_SUCCESS)
return result;
result = vdo_allocate(1, struct index_layout, __func__, &layout);
if (result != VDO_SUCCESS)
return result;
result = create_layout_factory(layout, config);
if (result != UDS_SUCCESS) {
uds_free_index_layout(layout);
return result;
}
if (layout->factory_size < sizes.total_size) {
vdo_log_error("index storage (%zu) is smaller than the required size %llu",
layout->factory_size,
(unsigned long long) sizes.total_size);
uds_free_index_layout(layout);
return -ENOSPC;
}
if (new_layout)
result = create_index_layout(layout, config);
else
result = load_index_layout(layout, config);
if (result != UDS_SUCCESS) {
uds_free_index_layout(layout);
return result;
}
*layout_ptr = layout;
return UDS_SUCCESS;
}
void uds_free_index_layout(struct index_layout *layout)
{
if (layout == NULL)
return;
vdo_free(layout->index.saves);
if (layout->factory != NULL)
uds_put_io_factory(layout->factory);
vdo_free(layout);
}
int uds_replace_index_layout_storage(struct index_layout *layout,
struct block_device *bdev)
{
return uds_replace_storage(layout->factory, bdev);
}
/* Obtain a dm_bufio_client for the volume region. */
int uds_open_volume_bufio(struct index_layout *layout, size_t block_size,
unsigned int reserved_buffers,
struct dm_bufio_client **client_ptr)
{
off_t offset = (layout->index.volume.start_block +
layout->super.volume_offset -
layout->super.start_offset);
return uds_make_bufio(layout->factory, offset, block_size, reserved_buffers,
client_ptr);
}
u64 uds_get_volume_nonce(struct index_layout *layout)
{
return layout->index.nonce;
}
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