new file mode 100644
@@ -0,0 +1,2983 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright Red Hat
+ */
+
+#include <linux/atomic.h>
+#include <linux/bitops.h>
+#include <linux/completion.h>
+#include <linux/delay.h>
+#include <linux/device-mapper.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/spinlock.h>
+
+#include "dm-vdo/admin-state.h"
+#include "dm-vdo/block-map.h"
+#include "dm-vdo/completion.h"
+#include "dm-vdo/constants.h"
+#include "dm-vdo/data-vio.h"
+#include "dm-vdo/dedupe.h"
+#include "dm-vdo/dump.h"
+#include "dm-vdo/encodings.h"
+#include "dm-vdo/errors.h"
+#include "dm-vdo/flush.h"
+#include "dm-vdo/io-submitter.h"
+#include "dm-vdo/logger.h"
+#include "dm-vdo/memory-alloc.h"
+#include "dm-vdo/message-stats.h"
+#include "dm-vdo/pool-sysfs.h"
+#include "dm-vdo/recovery-journal.h"
+#include "dm-vdo/repair.h"
+#include "dm-vdo/slab-depot.h"
+#include "dm-vdo/status-codes.h"
+#include "dm-vdo/string-utils.h"
+#include "dm-vdo/thread-device.h"
+#include "dm-vdo/thread-registry.h"
+#include "dm-vdo/types.h"
+#include "dm-vdo/uds-sysfs.h"
+#include "dm-vdo/vdo.h"
+#include "dm-vdo/vio.h"
+
+#define CURRENT_VERSION "8.3.0.20"
+
+enum {
+ GROW_LOGICAL_PHASE_START,
+ GROW_LOGICAL_PHASE_GROW_BLOCK_MAP,
+ GROW_LOGICAL_PHASE_END,
+ GROW_LOGICAL_PHASE_ERROR,
+ GROW_PHYSICAL_PHASE_START,
+ GROW_PHYSICAL_PHASE_COPY_SUMMARY,
+ GROW_PHYSICAL_PHASE_UPDATE_COMPONENTS,
+ GROW_PHYSICAL_PHASE_USE_NEW_SLABS,
+ GROW_PHYSICAL_PHASE_END,
+ GROW_PHYSICAL_PHASE_ERROR,
+ LOAD_PHASE_START,
+ LOAD_PHASE_STATS,
+ LOAD_PHASE_LOAD_DEPOT,
+ LOAD_PHASE_MAKE_DIRTY,
+ LOAD_PHASE_PREPARE_TO_ALLOCATE,
+ LOAD_PHASE_SCRUB_SLABS,
+ LOAD_PHASE_DATA_REDUCTION,
+ LOAD_PHASE_FINISHED,
+ LOAD_PHASE_DRAIN_JOURNAL,
+ LOAD_PHASE_WAIT_FOR_READ_ONLY,
+ PRE_LOAD_PHASE_START,
+ PRE_LOAD_PHASE_LOAD_COMPONENTS,
+ PRE_LOAD_PHASE_END,
+ PREPARE_GROW_PHYSICAL_PHASE_START,
+ RESUME_PHASE_START,
+ RESUME_PHASE_ALLOW_READ_ONLY_MODE,
+ RESUME_PHASE_DEDUPE,
+ RESUME_PHASE_DEPOT,
+ RESUME_PHASE_JOURNAL,
+ RESUME_PHASE_BLOCK_MAP,
+ RESUME_PHASE_LOGICAL_ZONES,
+ RESUME_PHASE_PACKER,
+ RESUME_PHASE_FLUSHER,
+ RESUME_PHASE_DATA_VIOS,
+ RESUME_PHASE_END,
+ SUSPEND_PHASE_START,
+ SUSPEND_PHASE_PACKER,
+ SUSPEND_PHASE_DATA_VIOS,
+ SUSPEND_PHASE_DEDUPE,
+ SUSPEND_PHASE_FLUSHES,
+ SUSPEND_PHASE_LOGICAL_ZONES,
+ SUSPEND_PHASE_BLOCK_MAP,
+ SUSPEND_PHASE_JOURNAL,
+ SUSPEND_PHASE_DEPOT,
+ SUSPEND_PHASE_READ_ONLY_WAIT,
+ SUSPEND_PHASE_WRITE_SUPER_BLOCK,
+ SUSPEND_PHASE_END,
+};
+
+static const char * const ADMIN_PHASE_NAMES[] = {
+ "GROW_LOGICAL_PHASE_START",
+ "GROW_LOGICAL_PHASE_GROW_BLOCK_MAP",
+ "GROW_LOGICAL_PHASE_END",
+ "GROW_LOGICAL_PHASE_ERROR",
+ "GROW_PHYSICAL_PHASE_START",
+ "GROW_PHYSICAL_PHASE_COPY_SUMMARY",
+ "GROW_PHYSICAL_PHASE_UPDATE_COMPONENTS",
+ "GROW_PHYSICAL_PHASE_USE_NEW_SLABS",
+ "GROW_PHYSICAL_PHASE_END",
+ "GROW_PHYSICAL_PHASE_ERROR",
+ "LOAD_PHASE_START",
+ "LOAD_PHASE_STATS",
+ "LOAD_PHASE_LOAD_DEPOT",
+ "LOAD_PHASE_MAKE_DIRTY",
+ "LOAD_PHASE_PREPARE_TO_ALLOCATE",
+ "LOAD_PHASE_SCRUB_SLABS",
+ "LOAD_PHASE_DATA_REDUCTION",
+ "LOAD_PHASE_FINISHED",
+ "LOAD_PHASE_DRAIN_JOURNAL",
+ "LOAD_PHASE_WAIT_FOR_READ_ONLY",
+ "PRE_LOAD_PHASE_START",
+ "PRE_LOAD_PHASE_LOAD_COMPONENTS",
+ "PRE_LOAD_PHASE_END",
+ "PREPARE_GROW_PHYSICAL_PHASE_START",
+ "RESUME_PHASE_START",
+ "RESUME_PHASE_ALLOW_READ_ONLY_MODE",
+ "RESUME_PHASE_DEDUPE",
+ "RESUME_PHASE_DEPOT",
+ "RESUME_PHASE_JOURNAL",
+ "RESUME_PHASE_BLOCK_MAP",
+ "RESUME_PHASE_LOGICAL_ZONES",
+ "RESUME_PHASE_PACKER",
+ "RESUME_PHASE_FLUSHER",
+ "RESUME_PHASE_DATA_VIOS",
+ "RESUME_PHASE_END",
+ "SUSPEND_PHASE_START",
+ "SUSPEND_PHASE_PACKER",
+ "SUSPEND_PHASE_DATA_VIOS",
+ "SUSPEND_PHASE_DEDUPE",
+ "SUSPEND_PHASE_FLUSHES",
+ "SUSPEND_PHASE_LOGICAL_ZONES",
+ "SUSPEND_PHASE_BLOCK_MAP",
+ "SUSPEND_PHASE_JOURNAL",
+ "SUSPEND_PHASE_DEPOT",
+ "SUSPEND_PHASE_READ_ONLY_WAIT",
+ "SUSPEND_PHASE_WRITE_SUPER_BLOCK",
+ "SUSPEND_PHASE_END",
+};
+
+enum {
+ /* If we bump this, update the arrays below */
+ TABLE_VERSION = 4,
+};
+
+/* arrays for handling different table versions */
+static const u8 REQUIRED_ARGC[] = { 10, 12, 9, 7, 6 };
+/* pool name no longer used. only here for verification of older versions */
+static const u8 POOL_NAME_ARG_INDEX[] = { 8, 10, 8 };
+
+/*
+ * Track in-use instance numbers using a flat bit array.
+ *
+ * O(n) run time isn't ideal, but if we have 1000 VDO devices in use simultaneously we still only
+ * need to scan 16 words, so it's not likely to be a big deal compared to other resource usage.
+ */
+
+enum {
+ /*
+ * This minimum size for the bit array creates a numbering space of 0-999, which allows
+ * successive starts of the same volume to have different instance numbers in any
+ * reasonably-sized test. Changing instances on restart allows vdoMonReport to detect that
+ * the ephemeral stats have reset to zero.
+ */
+ BIT_COUNT_MINIMUM = 1000,
+ /** Grow the bit array by this many bits when needed */
+ BIT_COUNT_INCREMENT = 100,
+};
+
+struct instance_tracker {
+ unsigned int bit_count;
+ unsigned long *words;
+ unsigned int count;
+ unsigned int next;
+};
+
+static DEFINE_MUTEX(instances_lock);
+static struct instance_tracker instances;
+
+/**
+ * free_device_config() - Free a device config created by parse_device_config().
+ * @config: The config to free.
+ */
+static void free_device_config(struct device_config *config)
+{
+ if (config == NULL)
+ return;
+
+ if (config->owned_device != NULL)
+ dm_put_device(config->owning_target, config->owned_device);
+
+ UDS_FREE(config->parent_device_name);
+ UDS_FREE(config->original_string);
+
+ /* Reduce the chance a use-after-free (as in BZ 1669960) happens to work. */
+ memset(config, 0, sizeof(*config));
+ UDS_FREE(config);
+}
+
+/**
+ * get_version_number() - Decide the version number from argv.
+ *
+ * @argc: The number of table values.
+ * @argv: The array of table values.
+ * @error_ptr: A pointer to return a error string in.
+ * @version_ptr: A pointer to return the version.
+ *
+ * Return: VDO_SUCCESS or an error code.
+ */
+static int get_version_number(int argc, char **argv, char **error_ptr, unsigned int *version_ptr)
+{
+ /* version, if it exists, is in a form of V<n> */
+ if (sscanf(argv[0], "V%u", version_ptr) == 1) {
+ if (*version_ptr < 1 || *version_ptr > TABLE_VERSION) {
+ *error_ptr = "Unknown version number detected";
+ return VDO_BAD_CONFIGURATION;
+ }
+ } else {
+ /* V0 actually has no version number in the table string */
+ *version_ptr = 0;
+ }
+
+ /*
+ * V0 and V1 have no optional parameters. There will always be a parameter for thread
+ * config, even if it's a "." to show it's an empty list.
+ */
+ if (*version_ptr <= 1) {
+ if (argc != REQUIRED_ARGC[*version_ptr]) {
+ *error_ptr = "Incorrect number of arguments for version";
+ return VDO_BAD_CONFIGURATION;
+ }
+ } else if (argc < REQUIRED_ARGC[*version_ptr]) {
+ *error_ptr = "Incorrect number of arguments for version";
+ return VDO_BAD_CONFIGURATION;
+ }
+
+ if (*version_ptr != TABLE_VERSION) {
+ uds_log_warning("Detected version mismatch between kernel module and tools kernel: %d, tool: %d",
+ TABLE_VERSION,
+ *version_ptr);
+ uds_log_warning("Please consider upgrading management tools to match kernel.");
+ }
+ return VDO_SUCCESS;
+}
+
+/* Free a list of non-NULL string pointers, and then the list itself. */
+static void free_string_array(char **string_array)
+{
+ unsigned int offset;
+
+ for (offset = 0; string_array[offset] != NULL; offset++)
+ UDS_FREE(string_array[offset]);
+ UDS_FREE(string_array);
+}
+
+/*
+ * Split the input string into substrings, separated at occurrences of the indicated character,
+ * returning a null-terminated list of string pointers.
+ *
+ * The string pointers and the pointer array itself should both be freed with UDS_FREE() when no
+ * longer needed. This can be done with vdo_free_string_array (below) if the pointers in the array
+ * are not changed. Since the array and copied strings are allocated by this function, it may only
+ * be used in contexts where allocation is permitted.
+ *
+ * Empty substrings are not ignored; that is, returned substrings may be empty strings if the
+ * separator occurs twice in a row.
+ */
+static int split_string(const char *string, char separator, char ***substring_array_ptr)
+{
+ unsigned int current_substring = 0, substring_count = 1;
+ const char *s;
+ char **substrings;
+ int result;
+ ptrdiff_t length;
+
+ for (s = string; *s != 0; s++)
+ if (*s == separator)
+ substring_count++;
+
+ result = UDS_ALLOCATE(substring_count + 1, char *, "string-splitting array", &substrings);
+ if (result != UDS_SUCCESS)
+ return result;
+
+ for (s = string; *s != 0; s++) {
+ if (*s == separator) {
+ ptrdiff_t length = s - string;
+
+ result = UDS_ALLOCATE(length + 1,
+ char,
+ "split string",
+ &substrings[current_substring]);
+ if (result != UDS_SUCCESS) {
+ free_string_array(substrings);
+ return result;
+ }
+ /*
+ * Trailing NUL is already in place after allocation; deal with the zero or
+ * more non-NUL bytes in the string.
+ */
+ if (length > 0)
+ memcpy(substrings[current_substring], string, length);
+ string = s + 1;
+ current_substring++;
+ BUG_ON(current_substring >= substring_count);
+ }
+ }
+ /* Process final string, with no trailing separator. */
+ BUG_ON(current_substring != (substring_count - 1));
+ length = strlen(string);
+
+ result = UDS_ALLOCATE(length + 1, char, "split string", &substrings[current_substring]);
+ if (result != UDS_SUCCESS) {
+ free_string_array(substrings);
+ return result;
+ }
+ memcpy(substrings[current_substring], string, length);
+ current_substring++;
+ /* substrings[current_substring] is NULL already */
+ *substring_array_ptr = substrings;
+ return UDS_SUCCESS;
+}
+
+/*
+ * Join the input substrings into one string, joined with the indicated character, returning a
+ * string. array_length is a bound on the number of valid elements in substring_array, in case it
+ * is not NULL-terminated.
+ */
+static int
+join_strings(char **substring_array, size_t array_length, char separator, char **string_ptr)
+{
+ size_t string_length = 0;
+ size_t i;
+ int result;
+ char *output, *current_position;
+
+ for (i = 0; (i < array_length) && (substring_array[i] != NULL); i++)
+ string_length += strlen(substring_array[i]) + 1;
+
+ result = UDS_ALLOCATE(string_length, char, __func__, &output);
+ if (result != VDO_SUCCESS)
+ return result;
+
+ current_position = &output[0];
+
+ for (i = 0; (i < array_length) && (substring_array[i] != NULL); i++) {
+ current_position = uds_append_to_buffer(current_position,
+ output + string_length,
+ "%s",
+ substring_array[i]);
+ *current_position = separator;
+ current_position++;
+ }
+
+ /* We output one too many separators; replace the last with a zero byte. */
+ if (current_position != output)
+ *(current_position - 1) = '\0';
+
+ *string_ptr = output;
+ return UDS_SUCCESS;
+}
+
+/**
+ * parse_bool() - Parse a two-valued option into a bool.
+ * @bool_str: The string value to convert to a bool.
+ * @true_str: The string value which should be converted to true.
+ * @false_str: The string value which should be converted to false.
+ * @bool_ptr: A pointer to return the bool value in.
+ *
+ * Return: VDO_SUCCESS or an error if bool_str is neither true_str nor false_str.
+ */
+static inline int __must_check
+parse_bool(const char *bool_str, const char *true_str, const char *false_str, bool *bool_ptr)
+{
+ bool value = false;
+
+ if (strcmp(bool_str, true_str) == 0)
+ value = true;
+ else if (strcmp(bool_str, false_str) == 0)
+ value = false;
+ else
+ return VDO_BAD_CONFIGURATION;
+
+ *bool_ptr = value;
+ return VDO_SUCCESS;
+}
+
+/**
+ * process_one_thread_config_spec() - Process one component of a thread parameter configuration
+ * string and update the configuration data structure.
+ * @thread_param_type: The type of thread specified.
+ * @count: The thread count requested.
+ * @config: The configuration data structure to update.
+ *
+ * If the thread count requested is invalid, a message is logged and -EINVAL returned. If the
+ * thread name is unknown, a message is logged but no error is returned.
+ *
+ * Return: VDO_SUCCESS or -EINVAL
+ */
+static int process_one_thread_config_spec(const char *thread_param_type,
+ unsigned int count,
+ struct thread_count_config *config)
+{
+ /* Handle limited thread parameters */
+ if (strcmp(thread_param_type, "bioRotationInterval") == 0) {
+ if (count == 0) {
+ uds_log_error("thread config string error: 'bioRotationInterval' of at least 1 is required");
+ return -EINVAL;
+ } else if (count > VDO_BIO_ROTATION_INTERVAL_LIMIT) {
+ uds_log_error("thread config string error: 'bioRotationInterval' cannot be higher than %d",
+ VDO_BIO_ROTATION_INTERVAL_LIMIT);
+ return -EINVAL;
+ }
+ config->bio_rotation_interval = count;
+ return VDO_SUCCESS;
+ }
+ if (strcmp(thread_param_type, "logical") == 0) {
+ if (count > MAX_VDO_LOGICAL_ZONES) {
+ uds_log_error("thread config string error: at most %d 'logical' threads are allowed",
+ MAX_VDO_LOGICAL_ZONES);
+ return -EINVAL;
+ }
+ config->logical_zones = count;
+ return VDO_SUCCESS;
+ }
+ if (strcmp(thread_param_type, "physical") == 0) {
+ if (count > MAX_VDO_PHYSICAL_ZONES) {
+ uds_log_error("thread config string error: at most %d 'physical' threads are allowed",
+ MAX_VDO_PHYSICAL_ZONES);
+ return -EINVAL;
+ }
+ config->physical_zones = count;
+ return VDO_SUCCESS;
+ }
+ /* Handle other thread count parameters */
+ if (count > MAXIMUM_VDO_THREADS) {
+ uds_log_error("thread config string error: at most %d '%s' threads are allowed",
+ MAXIMUM_VDO_THREADS,
+ thread_param_type);
+ return -EINVAL;
+ }
+ if (strcmp(thread_param_type, "hash") == 0) {
+ config->hash_zones = count;
+ return VDO_SUCCESS;
+ }
+ if (strcmp(thread_param_type, "cpu") == 0) {
+ if (count == 0) {
+ uds_log_error("thread config string error: at least one 'cpu' thread required");
+ return -EINVAL;
+ }
+ config->cpu_threads = count;
+ return VDO_SUCCESS;
+ }
+ if (strcmp(thread_param_type, "ack") == 0) {
+ config->bio_ack_threads = count;
+ return VDO_SUCCESS;
+ }
+ if (strcmp(thread_param_type, "bio") == 0) {
+ if (count == 0) {
+ uds_log_error("thread config string error: at least one 'bio' thread required");
+ return -EINVAL;
+ }
+ config->bio_threads = count;
+ return VDO_SUCCESS;
+ }
+
+ /*
+ * Don't fail, just log. This will handle version mismatches between user mode tools and
+ * kernel.
+ */
+ uds_log_info("unknown thread parameter type \"%s\"", thread_param_type);
+ return VDO_SUCCESS;
+}
+
+/**
+ * parse_one_thread_config_spec() - Parse one component of a thread parameter configuration string
+ * and update the configuration data structure.
+ * @spec: The thread parameter specification string.
+ * @config: The configuration data to be updated.
+ */
+static int parse_one_thread_config_spec(const char *spec, struct thread_count_config *config)
+{
+ unsigned int count;
+ char **fields;
+ int result;
+
+ result = split_string(spec, '=', &fields);
+ if (result != UDS_SUCCESS)
+ return result;
+
+ if ((fields[0] == NULL) || (fields[1] == NULL) || (fields[2] != NULL)) {
+ uds_log_error("thread config string error: expected thread parameter assignment, saw \"%s\"",
+ spec);
+ free_string_array(fields);
+ return -EINVAL;
+ }
+
+ result = kstrtouint(fields[1], 10, &count);
+ if (result != UDS_SUCCESS) {
+ uds_log_error("thread config string error: integer value needed, found \"%s\"",
+ fields[1]);
+ free_string_array(fields);
+ return result;
+ }
+
+ result = process_one_thread_config_spec(fields[0], count, config);
+ free_string_array(fields);
+ return result;
+}
+
+/**
+ * parse_thread_config_string() - Parse the configuration string passed and update the specified
+ * counts and other parameters of various types of threads to be
+ * created.
+ * @string: Thread parameter configuration string.
+ * @config: The thread configuration data to update.
+ *
+ * The configuration string should contain one or more comma-separated specs of the form
+ * "typename=number"; the supported type names are "cpu", "ack", "bio", "bioRotationInterval",
+ * "logical", "physical", and "hash".
+ *
+ * If an error occurs during parsing of a single key/value pair, we deem it serious enough to stop
+ * further parsing.
+ *
+ * This function can't set the "reason" value the caller wants to pass back, because we'd want to
+ * format it to say which field was invalid, and we can't allocate the "reason" strings
+ * dynamically. So if an error occurs, we'll log the details and pass back an error.
+ *
+ * Return: VDO_SUCCESS or -EINVAL or -ENOMEM
+ */
+static int parse_thread_config_string(const char *string, struct thread_count_config *config)
+{
+ int result = VDO_SUCCESS;
+ char **specs;
+
+ if (strcmp(".", string) != 0) {
+ unsigned int i;
+
+ result = split_string(string, ',', &specs);
+ if (result != UDS_SUCCESS)
+ return result;
+
+ for (i = 0; specs[i] != NULL; i++) {
+ result = parse_one_thread_config_spec(specs[i], config);
+ if (result != VDO_SUCCESS)
+ break;
+ }
+ free_string_array(specs);
+ }
+ return result;
+}
+
+/**
+ * process_one_key_value_pair() - Process one component of an optional parameter string and update
+ * the configuration data structure.
+ * @key: The optional parameter key name.
+ * @value: The optional parameter value.
+ * @config: The configuration data structure to update.
+ *
+ * If the value requested is invalid, a message is logged and -EINVAL returned. If the key is
+ * unknown, a message is logged but no error is returned.
+ *
+ * Return: VDO_SUCCESS or -EINVAL
+ */
+static int
+process_one_key_value_pair(const char *key, unsigned int value, struct device_config *config)
+{
+ /* Non thread optional parameters */
+ if (strcmp(key, "maxDiscard") == 0) {
+ if (value == 0) {
+ uds_log_error("optional parameter error: at least one max discard block required");
+ return -EINVAL;
+ }
+ /* Max discard sectors in blkdev_issue_discard is UINT_MAX >> 9 */
+ if (value > (UINT_MAX / VDO_BLOCK_SIZE)) {
+ uds_log_error("optional parameter error: at most %d max discard blocks are allowed",
+ UINT_MAX / VDO_BLOCK_SIZE);
+ return -EINVAL;
+ }
+ config->max_discard_blocks = value;
+ return VDO_SUCCESS;
+ }
+ /* Handles unknown key names */
+ return process_one_thread_config_spec(key, value, &config->thread_counts);
+}
+
+/**
+ * parse_one_key_value_pair() - Parse one key/value pair and update the configuration data
+ * structure.
+ * @key: The optional key name.
+ * @value: The optional value.
+ * @config: The configuration data to be updated.
+ *
+ * Return: VDO_SUCCESS or error.
+ */
+static int
+parse_one_key_value_pair(const char *key, const char *value, struct device_config *config)
+{
+ unsigned int count;
+ int result;
+
+ if (strcmp(key, "deduplication") == 0)
+ return parse_bool(value, "on", "off", &config->deduplication);
+
+ if (strcmp(key, "compression") == 0)
+ return parse_bool(value, "on", "off", &config->compression);
+
+ /* The remaining arguments must have integral values. */
+ result = kstrtouint(value, 10, &count);
+ if (result != UDS_SUCCESS) {
+ uds_log_error("optional config string error: integer value needed, found \"%s\"",
+ value);
+ return result;
+ }
+ return process_one_key_value_pair(key, count, config);
+}
+
+/**
+ * parse_key_value_pairs() - Parse all key/value pairs from a list of arguments.
+ * @argc: The total number of arguments in list.
+ * @argv: The list of key/value pairs.
+ * @config: The device configuration data to update.
+ *
+ * If an error occurs during parsing of a single key/value pair, we deem it serious enough to stop
+ * further parsing.
+ *
+ * This function can't set the "reason" value the caller wants to pass back, because we'd want to
+ * format it to say which field was invalid, and we can't allocate the "reason" strings
+ * dynamically. So if an error occurs, we'll log the details and return the error.
+ *
+ * Return: VDO_SUCCESS or error
+ */
+static int parse_key_value_pairs(int argc, char **argv, struct device_config *config)
+{
+ int result = VDO_SUCCESS;
+
+ while (argc) {
+ result = parse_one_key_value_pair(argv[0], argv[1], config);
+ if (result != VDO_SUCCESS)
+ break;
+
+ argc -= 2;
+ argv += 2;
+ }
+
+ return result;
+}
+
+/**
+ * parse_optional_arguments() - Parse the configuration string passed in for optional arguments.
+ * @arg_set: The structure holding the arguments to parse.
+ * @error_ptr: Pointer to a buffer to hold the error string.
+ * @config: Pointer to device configuration data to update.
+ *
+ * For V0/V1 configurations, there will only be one optional parameter; the thread configuration.
+ * The configuration string should contain one or more comma-separated specs of the form
+ * "typename=number"; the supported type names are "cpu", "ack", "bio", "bioRotationInterval",
+ * "logical", "physical", and "hash".
+ *
+ * For V2 configurations and beyond, there could be any number of arguments. They should contain
+ * one or more key/value pairs separated by a space.
+ *
+ * Return: VDO_SUCCESS or error
+ */
+static int parse_optional_arguments(struct dm_arg_set *arg_set,
+ char **error_ptr,
+ struct device_config *config)
+{
+ int result = VDO_SUCCESS;
+
+ if (config->version == 0 || config->version == 1) {
+ result = parse_thread_config_string(arg_set->argv[0], &config->thread_counts);
+ if (result != VDO_SUCCESS) {
+ *error_ptr = "Invalid thread-count configuration";
+ return VDO_BAD_CONFIGURATION;
+ }
+ } else {
+ if ((arg_set->argc % 2) != 0) {
+ *error_ptr = "Odd number of optional arguments given but they should be <key> <value> pairs";
+ return VDO_BAD_CONFIGURATION;
+ }
+ result = parse_key_value_pairs(arg_set->argc, arg_set->argv, config);
+ if (result != VDO_SUCCESS) {
+ *error_ptr = "Invalid optional argument configuration";
+ return VDO_BAD_CONFIGURATION;
+ }
+ }
+ return result;
+}
+
+/**
+ * handle_parse_error() - Handle a parsing error.
+ * @config: The config to free.
+ * @error_ptr: A place to store a constant string about the error.
+ * @error_str: A constant string to store in error_ptr.
+ */
+static void handle_parse_error(struct device_config *config, char **error_ptr, char *error_str)
+{
+ free_device_config(config);
+ *error_ptr = error_str;
+}
+
+/**
+ * parse_device_config() - Convert the dmsetup table into a struct device_config.
+ * @argc: The number of table values.
+ * @argv: The array of table values.
+ * @ti: The target structure for this table.
+ * @config_ptr: A pointer to return the allocated config.
+ *
+ * Return: VDO_SUCCESS or an error code.
+ */
+static int parse_device_config(int argc,
+ char **argv,
+ struct dm_target *ti,
+ struct device_config **config_ptr)
+{
+ bool enable_512e;
+ size_t logical_bytes = to_bytes(ti->len);
+ struct dm_arg_set arg_set;
+ char **error_ptr = &ti->error;
+ struct device_config *config = NULL;
+ int result;
+
+ if ((logical_bytes % VDO_BLOCK_SIZE) != 0) {
+ handle_parse_error(config, error_ptr, "Logical size must be a multiple of 4096");
+ return VDO_BAD_CONFIGURATION;
+ }
+
+ if (argc == 0) {
+ handle_parse_error(config, error_ptr, "Incorrect number of arguments");
+ return VDO_BAD_CONFIGURATION;
+ }
+
+ result = UDS_ALLOCATE(1, struct device_config, "device_config", &config);
+ if (result != VDO_SUCCESS) {
+ handle_parse_error(config, error_ptr, "Could not allocate config structure");
+ return VDO_BAD_CONFIGURATION;
+ }
+
+ config->owning_target = ti;
+ config->logical_blocks = logical_bytes / VDO_BLOCK_SIZE;
+ INIT_LIST_HEAD(&config->config_list);
+
+ /* Save the original string. */
+ result = join_strings(argv, argc, ' ', &config->original_string);
+ if (result != VDO_SUCCESS) {
+ handle_parse_error(config, error_ptr, "Could not populate string");
+ return VDO_BAD_CONFIGURATION;
+ }
+
+ uds_log_info("table line: %s", config->original_string);
+
+ config->thread_counts = (struct thread_count_config) {
+ .bio_ack_threads = 1,
+ .bio_threads = DEFAULT_VDO_BIO_SUBMIT_QUEUE_COUNT,
+ .bio_rotation_interval = DEFAULT_VDO_BIO_SUBMIT_QUEUE_ROTATE_INTERVAL,
+ .cpu_threads = 1,
+ .logical_zones = 0,
+ .physical_zones = 0,
+ .hash_zones = 0,
+ };
+ config->max_discard_blocks = 1;
+ config->deduplication = true;
+ config->compression = false;
+
+ arg_set.argc = argc;
+ arg_set.argv = argv;
+
+ result = get_version_number(argc, argv, error_ptr, &config->version);
+ if (result != VDO_SUCCESS) {
+ /* get_version_number sets error_ptr itself. */
+ handle_parse_error(config, error_ptr, *error_ptr);
+ return result;
+ }
+ /* Move the arg pointer forward only if the argument was there. */
+ if (config->version >= 1)
+ dm_shift_arg(&arg_set);
+
+ result = uds_duplicate_string(dm_shift_arg(&arg_set),
+ "parent device name",
+ &config->parent_device_name);
+ if (result != VDO_SUCCESS) {
+ handle_parse_error(config, error_ptr, "Could not copy parent device name");
+ return VDO_BAD_CONFIGURATION;
+ }
+
+ /* Get the physical blocks, if known. */
+ if (config->version >= 1) {
+ result = kstrtoull(dm_shift_arg(&arg_set), 10, &config->physical_blocks);
+ if (result != VDO_SUCCESS) {
+ handle_parse_error(config, error_ptr, "Invalid physical block count");
+ return VDO_BAD_CONFIGURATION;
+ }
+ }
+
+ /* Get the logical block size and validate */
+ result = parse_bool(dm_shift_arg(&arg_set), "512", "4096", &enable_512e);
+ if (result != VDO_SUCCESS) {
+ handle_parse_error(config, error_ptr, "Invalid logical block size");
+ return VDO_BAD_CONFIGURATION;
+ }
+ config->logical_block_size = (enable_512e ? 512 : 4096);
+
+ /* Skip past the two no longer used read cache options. */
+ if (config->version <= 1)
+ dm_consume_args(&arg_set, 2);
+
+ /* Get the page cache size. */
+ result = kstrtouint(dm_shift_arg(&arg_set), 10, &config->cache_size);
+ if (result != VDO_SUCCESS) {
+ handle_parse_error(config, error_ptr, "Invalid block map page cache size");
+ return VDO_BAD_CONFIGURATION;
+ }
+
+ /* Get the block map era length. */
+ result = kstrtouint(dm_shift_arg(&arg_set), 10, &config->block_map_maximum_age);
+ if (result != VDO_SUCCESS) {
+ handle_parse_error(config, error_ptr, "Invalid block map maximum age");
+ return VDO_BAD_CONFIGURATION;
+ }
+
+ /* Skip past the no longer used MD RAID5 optimization mode */
+ if (config->version <= 2)
+ dm_consume_args(&arg_set, 1);
+
+ /* Skip past the no longer used write policy setting */
+ if (config->version <= 3)
+ dm_consume_args(&arg_set, 1);
+
+ /* Skip past the no longer used pool name for older table lines */
+ if (config->version <= 2) {
+ /*
+ * Make sure the enum to get the pool name from argv directly is still in sync with
+ * the parsing of the table line.
+ */
+ if (&arg_set.argv[0] != &argv[POOL_NAME_ARG_INDEX[config->version]]) {
+ handle_parse_error(config, error_ptr, "Pool name not in expected location");
+ return VDO_BAD_CONFIGURATION;
+ }
+ dm_shift_arg(&arg_set);
+ }
+
+ /* Get the optional arguments and validate. */
+ result = parse_optional_arguments(&arg_set, error_ptr, config);
+ if (result != VDO_SUCCESS) {
+ /* parse_optional_arguments sets error_ptr itself. */
+ handle_parse_error(config, error_ptr, *error_ptr);
+ return result;
+ }
+
+ /*
+ * Logical, physical, and hash zone counts can all be zero; then we get one thread doing
+ * everything, our older configuration. If any zone count is non-zero, the others must be
+ * as well.
+ */
+ if (((config->thread_counts.logical_zones == 0) !=
+ (config->thread_counts.physical_zones == 0)) ||
+ ((config->thread_counts.physical_zones == 0) !=
+ (config->thread_counts.hash_zones == 0))) {
+ handle_parse_error(config,
+ error_ptr,
+ "Logical, physical, and hash zones counts must all be zero or all non-zero");
+ return VDO_BAD_CONFIGURATION;
+ }
+
+ if (config->cache_size <
+ (2 * MAXIMUM_VDO_USER_VIOS * config->thread_counts.logical_zones)) {
+ handle_parse_error(config,
+ error_ptr,
+ "Insufficient block map cache for logical zones");
+ return VDO_BAD_CONFIGURATION;
+ }
+
+ result = dm_get_device(ti,
+ config->parent_device_name,
+ dm_table_get_mode(ti->table),
+ &config->owned_device);
+ if (result != 0) {
+ uds_log_error("couldn't open device \"%s\": error %d",
+ config->parent_device_name,
+ result);
+ handle_parse_error(config, error_ptr, "Unable to open storage device");
+ return VDO_BAD_CONFIGURATION;
+ }
+
+ if (config->version == 0) {
+ u64 device_size = i_size_read(config->owned_device->bdev->bd_inode);
+
+ config->physical_blocks = device_size / VDO_BLOCK_SIZE;
+ }
+
+ *config_ptr = config;
+ return result;
+}
+
+static struct vdo *get_vdo_for_target(struct dm_target *ti)
+{
+ return ((struct device_config *) ti->private)->vdo;
+}
+
+
+static int vdo_map_bio(struct dm_target *ti, struct bio *bio)
+{
+ struct vdo *vdo = get_vdo_for_target(ti);
+ struct vdo_work_queue *current_work_queue;
+ const struct admin_state_code *code = vdo_get_admin_state_code(&vdo->admin.state);
+
+ ASSERT_LOG_ONLY(code->normal, "vdo should not receive bios while in state %s", code->name);
+
+ /* Count all incoming bios. */
+ vdo_count_bios(&vdo->stats.bios_in, bio);
+
+
+ /* Handle empty bios. Empty flush bios are not associated with a vio. */
+ if ((bio_op(bio) == REQ_OP_FLUSH) || ((bio->bi_opf & REQ_PREFLUSH) != 0)) {
+ vdo_launch_flush(vdo, bio);
+ return DM_MAPIO_SUBMITTED;
+ }
+
+ /* This could deadlock, */
+ current_work_queue = vdo_get_current_work_queue();
+ BUG_ON((current_work_queue != NULL) &&
+ (vdo == vdo_get_work_queue_owner(current_work_queue)->vdo));
+ vdo_launch_bio(vdo->data_vio_pool, bio);
+ return DM_MAPIO_SUBMITTED;
+}
+
+static void vdo_io_hints(struct dm_target *ti, struct queue_limits *limits)
+{
+ struct vdo *vdo = get_vdo_for_target(ti);
+
+ limits->logical_block_size = vdo->device_config->logical_block_size;
+ limits->physical_block_size = VDO_BLOCK_SIZE;
+
+ /* The minimum io size for random io */
+ blk_limits_io_min(limits, VDO_BLOCK_SIZE);
+ /* The optimal io size for streamed/sequential io */
+ blk_limits_io_opt(limits, VDO_BLOCK_SIZE);
+
+ /*
+ * Sets the maximum discard size that will be passed into VDO. This value comes from a
+ * table line value passed in during dmsetup create.
+ *
+ * The value 1024 is the largest usable value on HD systems. A 2048 sector discard on a
+ * busy HD system takes 31 seconds. We should use a value no higher than 1024, which takes
+ * 15 to 16 seconds on a busy HD system.
+ *
+ * But using large values results in 120 second blocked task warnings in /var/log/kern.log.
+ * In order to avoid these warnings, we choose to use the smallest reasonable value. See
+ * VDO-3062 and VDO-3087.
+ *
+ * The value is displayed in sysfs, and also used by dm-thin to determine whether to pass
+ * down discards. The block layer splits large discards on this boundary when this is set.
+ */
+ limits->max_discard_sectors =
+ (vdo->device_config->max_discard_blocks * VDO_SECTORS_PER_BLOCK);
+
+ /*
+ * Force discards to not begin or end with a partial block by stating the granularity is
+ * 4k.
+ */
+ limits->discard_granularity = VDO_BLOCK_SIZE;
+}
+
+static int vdo_iterate_devices(struct dm_target *ti, iterate_devices_callout_fn fn, void *data)
+{
+ struct device_config *config = get_vdo_for_target(ti)->device_config;
+
+ return fn(ti,
+ config->owned_device,
+ 0,
+ config->physical_blocks * VDO_SECTORS_PER_BLOCK,
+ data);
+}
+
+/*
+ * Status line is:
+ * <device> <operating mode> <in recovery> <index state> <compression state>
+ * <used physical blocks> <total physical blocks>
+ */
+
+static void vdo_status(struct dm_target *ti,
+ status_type_t status_type,
+ unsigned int status_flags,
+ char *result,
+ unsigned int maxlen)
+{
+ struct vdo *vdo = get_vdo_for_target(ti);
+ struct vdo_statistics *stats;
+ struct device_config *device_config;
+ /* N.B.: The DMEMIT macro uses the variables named "sz", "result", "maxlen". */
+ int sz = 0;
+
+ switch (status_type) {
+ case STATUSTYPE_INFO:
+ /* Report info for dmsetup status */
+ mutex_lock(&vdo->stats_mutex);
+ vdo_fetch_statistics(vdo, &vdo->stats_buffer);
+ stats = &vdo->stats_buffer;
+
+ DMEMIT("/dev/%pg %s %s %s %s %llu %llu",
+ vdo_get_backing_device(vdo),
+ stats->mode,
+ stats->in_recovery_mode ? "recovering" : "-",
+ vdo_get_dedupe_index_state_name(vdo->hash_zones),
+ vdo_get_compressing(vdo) ? "online" : "offline",
+ stats->data_blocks_used + stats->overhead_blocks_used,
+ stats->physical_blocks);
+ mutex_unlock(&vdo->stats_mutex);
+ break;
+
+ case STATUSTYPE_TABLE:
+ /* Report the string actually specified in the beginning. */
+ device_config = (struct device_config *) ti->private;
+ DMEMIT("%s", device_config->original_string);
+ break;
+
+ case STATUSTYPE_IMA:
+ /* FIXME: We ought to be more detailed here, but this is what thin does. */
+ *result = '\0';
+ break;
+ }
+}
+
+static block_count_t __must_check get_underlying_device_block_count(const struct vdo *vdo)
+{
+ return i_size_read(vdo_get_backing_device(vdo)->bd_inode) / VDO_BLOCK_SIZE;
+}
+
+static int __must_check process_vdo_message_locked(struct vdo *vdo, unsigned int argc, char **argv)
+{
+ if ((argc == 2) && (strcasecmp(argv[0], "compression") == 0)) {
+ if (strcasecmp(argv[1], "on") == 0) {
+ vdo_set_compressing(vdo, true);
+ return 0;
+ }
+
+ if (strcasecmp(argv[1], "off") == 0) {
+ vdo_set_compressing(vdo, false);
+ return 0;
+ }
+
+ uds_log_warning("invalid argument '%s' to dmsetup compression message", argv[1]);
+ return -EINVAL;
+ }
+
+ uds_log_warning("unrecognized dmsetup message '%s' received", argv[0]);
+ return -EINVAL;
+}
+
+/*
+ * If the message is a dump, just do it. Otherwise, check that no other message is being processed,
+ * and only proceed if so.
+ * Returns -EBUSY if another message is being processed
+ */
+static int __must_check process_vdo_message(struct vdo *vdo, unsigned int argc, char **argv)
+{
+ int result;
+
+ /*
+ * All messages which may be processed in parallel with other messages should be handled
+ * here before the atomic check below. Messages which should be exclusive should be
+ * processed in process_vdo_message_locked().
+ */
+
+ /* Dump messages should always be processed */
+ if (strcasecmp(argv[0], "dump") == 0)
+ return vdo_dump(vdo, argc, argv, "dmsetup message");
+
+ if (argc == 1) {
+ if (strcasecmp(argv[0], "dump-on-shutdown") == 0) {
+ vdo->dump_on_shutdown = true;
+ return 0;
+ }
+
+ /* Index messages should always be processed */
+ if ((strcasecmp(argv[0], "index-close") == 0) ||
+ (strcasecmp(argv[0], "index-create") == 0) ||
+ (strcasecmp(argv[0], "index-disable") == 0) ||
+ (strcasecmp(argv[0], "index-enable") == 0))
+ return vdo_message_dedupe_index(vdo->hash_zones, argv[0]);
+ }
+
+ if (atomic_cmpxchg(&vdo->processing_message, 0, 1) != 0)
+ return -EBUSY;
+
+ result = process_vdo_message_locked(vdo, argc, argv);
+
+ /* Pairs with the implicit barrier in cmpxchg just above */
+ smp_wmb();
+ atomic_set(&vdo->processing_message, 0);
+ return result;
+}
+
+static int vdo_message(struct dm_target *ti,
+ unsigned int argc,
+ char **argv,
+ char *result_buffer,
+ unsigned int maxlen)
+{
+ struct registered_thread allocating_thread, instance_thread;
+ struct vdo *vdo;
+ int result;
+
+ if (argc == 0) {
+ uds_log_warning("unspecified dmsetup message");
+ return -EINVAL;
+ }
+
+ vdo = get_vdo_for_target(ti);
+ uds_register_allocating_thread(&allocating_thread, NULL);
+ uds_register_thread_device_id(&instance_thread, &vdo->instance);
+
+ /*
+ * Must be done here so we don't map return codes. The code in dm-ioctl expects a 1 for a
+ * return code to look at the buffer and see if it is full or not.
+ */
+ if ((argc == 1) && (strcasecmp(argv[0], "stats") == 0)) {
+ vdo_write_stats(vdo, result_buffer, maxlen);
+ result = 1;
+ } else {
+ result = vdo_map_to_system_error(process_vdo_message(vdo, argc, argv));
+ }
+
+ uds_unregister_thread_device_id();
+ uds_unregister_allocating_thread();
+ return result;
+}
+
+static void configure_target_capabilities(struct dm_target *ti)
+{
+ ti->discards_supported = 1;
+ ti->flush_supported = true;
+ ti->num_discard_bios = 1;
+ ti->num_flush_bios = 1;
+
+ /*
+ * If this value changes, please make sure to update the value for max_discard_sectors
+ * accordingly.
+ */
+ BUG_ON(dm_set_target_max_io_len(ti, VDO_SECTORS_PER_BLOCK) != 0);
+}
+
+/*
+ * Implements vdo_filter_t.
+ */
+static bool vdo_uses_device(struct vdo *vdo, const void *context)
+{
+ const struct device_config *config = context;
+
+ return vdo_get_backing_device(vdo)->bd_dev == config->owned_device->bdev->bd_dev;
+}
+
+/**
+ * get_thread_id_for_phase() - Get the thread id for the current phase of the admin operation in
+ * progress.
+ */
+static thread_id_t __must_check
+get_thread_id_for_phase(struct vdo *vdo)
+{
+ switch (vdo->admin.phase) {
+ case RESUME_PHASE_PACKER:
+ case RESUME_PHASE_FLUSHER:
+ case SUSPEND_PHASE_PACKER:
+ case SUSPEND_PHASE_FLUSHES:
+ return vdo->thread_config.packer_thread;
+
+ case RESUME_PHASE_DATA_VIOS:
+ case SUSPEND_PHASE_DATA_VIOS:
+ return vdo->thread_config.cpu_thread;
+
+ case LOAD_PHASE_DRAIN_JOURNAL:
+ case RESUME_PHASE_JOURNAL:
+ case SUSPEND_PHASE_JOURNAL:
+ return vdo->thread_config.journal_thread;
+
+ default:
+ return vdo->thread_config.admin_thread;
+ }
+}
+
+static struct vdo_completion *prepare_admin_completion(struct vdo *vdo,
+ vdo_action *callback,
+ vdo_action *error_handler)
+{
+ struct vdo_completion *completion = &vdo->admin.completion;
+
+ /*
+ * We can't use vdo_prepare_completion_for_requeue() here because we don't want to reset
+ * any error in the completion.
+ */
+ completion->callback = callback;
+ completion->error_handler = error_handler;
+ completion->callback_thread_id = get_thread_id_for_phase(vdo);
+ completion->requeue = true;
+ return completion;
+}
+
+/**
+ * advance_phase() - Increment the phase of the current admin operation and prepare the admin
+ * completion to run on the thread for the next phase.
+ * @vdo: The on which an admin operation is being performed
+ *
+ * Return: The current phase
+ */
+static u32 advance_phase(struct vdo *vdo)
+{
+ u32 phase = vdo->admin.phase++;
+
+ vdo->admin.completion.callback_thread_id = get_thread_id_for_phase(vdo);
+ vdo->admin.completion.requeue = true;
+ return phase;
+}
+
+/*
+ * Perform an administrative operation (load, suspend, grow logical, or grow physical). This method
+ * should not be called from vdo threads.
+ */
+static int perform_admin_operation(struct vdo *vdo,
+ u32 starting_phase,
+ vdo_action *callback,
+ vdo_action *error_handler,
+ const char *type)
+{
+ int result;
+ struct vdo_administrator *admin = &vdo->admin;
+
+ if (atomic_cmpxchg(&admin->busy, 0, 1) != 0)
+ return uds_log_error_strerror(VDO_COMPONENT_BUSY,
+ "Can't start %s operation, another operation is already in progress",
+ type);
+
+ admin->phase = starting_phase;
+ reinit_completion(&admin->callback_sync);
+ vdo_reset_completion(&admin->completion);
+ vdo_launch_completion(prepare_admin_completion(vdo, callback, error_handler));
+
+ /*
+ * Using the "interruptible" interface means that Linux will not log a message when we wait
+ * for more than 120 seconds.
+ */
+ while (wait_for_completion_interruptible(&admin->callback_sync) != 0)
+ /* * However, if we get a signal in a user-mode process, we could spin... */
+ fsleep(1000);
+
+ result = admin->completion.result;
+ /* pairs with implicit barrier in cmpxchg above */
+ smp_wmb();
+ atomic_set(&admin->busy, 0);
+ return result;
+}
+
+/* Assert that we are operating on the correct thread for the current phase. */
+static void assert_admin_phase_thread(struct vdo *vdo, const char *what)
+{
+ ASSERT_LOG_ONLY(vdo_get_callback_thread_id() == get_thread_id_for_phase(vdo),
+ "%s on correct thread for %s",
+ what,
+ ADMIN_PHASE_NAMES[vdo->admin.phase]);
+}
+
+/**
+ * finish_operation_callback() - Callback to finish an admin operation.
+ * @completion: The admin_completion.
+ */
+static void finish_operation_callback(struct vdo_completion *completion)
+{
+ struct vdo_administrator *admin = &completion->vdo->admin;
+
+ vdo_finish_operation(&admin->state, completion->result);
+ complete(&admin->callback_sync);
+}
+
+/**
+ * decode_from_super_block() - Decode the VDO state from the super block and validate that it is
+ * correct.
+ * @vdo: The vdo being loaded.
+ *
+ * On error from this method, the component states must be destroyed explicitly. If this method
+ * returns successfully, the component states must not be destroyed.
+ *
+ * Return: VDO_SUCCESS or an error.
+ */
+static int __must_check decode_from_super_block(struct vdo *vdo)
+{
+ const struct device_config *config = vdo->device_config;
+ int result;
+
+ result = vdo_decode_component_states(vdo->super_block.buffer,
+ &vdo->geometry,
+ &vdo->states);
+ if (result != VDO_SUCCESS)
+ return result;
+
+ vdo_set_state(vdo, vdo->states.vdo.state);
+ vdo->load_state = vdo->states.vdo.state;
+
+ /*
+ * If the device config specifies a larger logical size than was recorded in the super
+ * block, just accept it.
+ */
+ if (vdo->states.vdo.config.logical_blocks < config->logical_blocks) {
+ uds_log_warning("Growing logical size: a logical size of %llu blocks was specified, but that differs from the %llu blocks configured in the vdo super block",
+ (unsigned long long) config->logical_blocks,
+ (unsigned long long) vdo->states.vdo.config.logical_blocks);
+ vdo->states.vdo.config.logical_blocks = config->logical_blocks;
+ }
+
+ result = vdo_validate_component_states(&vdo->states,
+ vdo->geometry.nonce,
+ config->physical_blocks,
+ config->logical_blocks);
+ if (result != VDO_SUCCESS)
+ return result;
+
+ vdo->layout = vdo->states.layout;
+ return VDO_SUCCESS;
+}
+
+/**
+ * decode_vdo() - Decode the component data portion of a super block and fill in the corresponding
+ * portions of the vdo being loaded.
+ * @vdo: The vdo being loaded.
+ *
+ * This will also allocate the recovery journal and slab depot. If this method is called with an
+ * asynchronous layer (i.e. a thread config which specifies at least one base thread), the block
+ * map and packer will be constructed as well.
+ *
+ * Return: VDO_SUCCESS or an error.
+ */
+static int __must_check decode_vdo(struct vdo *vdo)
+{
+ block_count_t maximum_age, journal_length;
+ struct partition *partition;
+ int result;
+
+ result = decode_from_super_block(vdo);
+ if (result != VDO_SUCCESS) {
+ vdo_destroy_component_states(&vdo->states);
+ return result;
+ }
+
+ maximum_age = vdo_convert_maximum_age(vdo->device_config->block_map_maximum_age);
+ journal_length =
+ vdo_get_recovery_journal_length(vdo->states.vdo.config.recovery_journal_size);
+ if (maximum_age > (journal_length / 2))
+ return uds_log_error_strerror(VDO_BAD_CONFIGURATION,
+ "maximum age: %llu exceeds limit %llu",
+ (unsigned long long) maximum_age,
+ (unsigned long long) (journal_length / 2));
+
+ if (maximum_age == 0)
+ return uds_log_error_strerror(VDO_BAD_CONFIGURATION,
+ "maximum age must be greater than 0");
+
+ result = vdo_enable_read_only_entry(vdo);
+ if (result != VDO_SUCCESS)
+ return result;
+
+ partition = vdo_get_known_partition(&vdo->layout, VDO_RECOVERY_JOURNAL_PARTITION);
+ result = vdo_decode_recovery_journal(vdo->states.recovery_journal,
+ vdo->states.vdo.nonce,
+ vdo,
+ partition,
+ vdo->states.vdo.complete_recoveries,
+ vdo->states.vdo.config.recovery_journal_size,
+ &vdo->recovery_journal);
+ if (result != VDO_SUCCESS)
+ return result;
+
+ partition = vdo_get_known_partition(&vdo->layout, VDO_SLAB_SUMMARY_PARTITION);
+ result = vdo_decode_slab_depot(vdo->states.slab_depot,
+ vdo,
+ partition,
+ &vdo->depot);
+ if (result != VDO_SUCCESS)
+ return result;
+
+ result = vdo_decode_block_map(vdo->states.block_map,
+ vdo->states.vdo.config.logical_blocks,
+ vdo,
+ vdo->recovery_journal,
+ vdo->states.vdo.nonce,
+ vdo->device_config->cache_size,
+ maximum_age,
+ &vdo->block_map);
+ if (result != VDO_SUCCESS)
+ return result;
+
+ result = vdo_make_physical_zones(vdo, &vdo->physical_zones);
+ if (result != VDO_SUCCESS)
+ return result;
+
+ /* The logical zones depend on the physical zones already existing. */
+ result = vdo_make_logical_zones(vdo, &vdo->logical_zones);
+ if (result != VDO_SUCCESS)
+ return result;
+
+ return vdo_make_hash_zones(vdo, &vdo->hash_zones);
+}
+
+/**
+ * pre_load_callback() - Callback to initiate a pre-load, registered in vdo_initialize().
+ * @completion: The admin completion.
+ */
+static void pre_load_callback(struct vdo_completion *completion)
+{
+ struct vdo *vdo = completion->vdo;
+ int result;
+
+ assert_admin_phase_thread(vdo, __func__);
+
+ switch (advance_phase(vdo)) {
+ case PRE_LOAD_PHASE_START:
+ result = vdo_start_operation(&vdo->admin.state, VDO_ADMIN_STATE_PRE_LOADING);
+ if (result != VDO_SUCCESS) {
+ vdo_continue_completion(completion, result);
+ return;
+ }
+
+ vdo_load_super_block(vdo, completion);
+ return;
+
+ case PRE_LOAD_PHASE_LOAD_COMPONENTS:
+ vdo_continue_completion(completion, decode_vdo(vdo));
+ return;
+
+ case PRE_LOAD_PHASE_END:
+ break;
+
+ default:
+ vdo_set_completion_result(completion, UDS_BAD_STATE);
+ }
+
+ finish_operation_callback(completion);
+}
+
+static void release_instance(unsigned int instance)
+{
+ mutex_lock(&instances_lock);
+ if (instance >= instances.bit_count) {
+ ASSERT_LOG_ONLY(false,
+ "instance number %u must be less than bit count %u",
+ instance,
+ instances.bit_count);
+ } else if (test_bit(instance, instances.words) == 0) {
+ ASSERT_LOG_ONLY(false, "instance number %u must be allocated", instance);
+ } else {
+ __clear_bit(instance, instances.words);
+ instances.count -= 1;
+ }
+ mutex_unlock(&instances_lock);
+}
+
+static void set_device_config(struct dm_target *ti, struct vdo *vdo, struct device_config *config)
+{
+ list_del_init(&config->config_list);
+ list_add_tail(&config->config_list, &vdo->device_config_list);
+ config->vdo = vdo;
+ ti->private = config;
+ configure_target_capabilities(ti);
+}
+
+static int
+vdo_initialize(struct dm_target *ti, unsigned int instance, struct device_config *config)
+{
+ struct vdo *vdo;
+ int result;
+ u64 block_size = VDO_BLOCK_SIZE;
+ u64 logical_size = to_bytes(ti->len);
+ block_count_t logical_blocks = logical_size / block_size;
+
+ uds_log_info("loading device '%s'", vdo_get_device_name(ti));
+ uds_log_debug("Logical block size = %llu", (u64) config->logical_block_size);
+ uds_log_debug("Logical blocks = %llu", logical_blocks);
+ uds_log_debug("Physical block size = %llu", (u64) block_size);
+ uds_log_debug("Physical blocks = %llu", config->physical_blocks);
+ uds_log_debug("Block map cache blocks = %u", config->cache_size);
+ uds_log_debug("Block map maximum age = %u", config->block_map_maximum_age);
+ uds_log_debug("Deduplication = %s", (config->deduplication ? "on" : "off"));
+ uds_log_debug("Compression = %s", (config->compression ? "on" : "off"));
+
+ vdo = vdo_find_matching(vdo_uses_device, config);
+ if (vdo != NULL) {
+ uds_log_error("Existing vdo already uses device %s",
+ vdo->device_config->parent_device_name);
+ ti->error = "Cannot share storage device with already-running VDO";
+ return VDO_BAD_CONFIGURATION;
+ }
+
+ result = vdo_make(instance, config, &ti->error, &vdo);
+ if (result != VDO_SUCCESS) {
+ uds_log_error("Could not create VDO device. (VDO error %d, message %s)",
+ result,
+ ti->error);
+ vdo_destroy(vdo);
+ return result;
+ }
+
+ result = perform_admin_operation(vdo,
+ PRE_LOAD_PHASE_START,
+ pre_load_callback,
+ finish_operation_callback,
+ "pre-load");
+ if (result != VDO_SUCCESS) {
+ ti->error = ((result == VDO_INVALID_ADMIN_STATE) ?
+ "Pre-load is only valid immediately after initialization" :
+ "Cannot load metadata from device");
+ uds_log_error("Could not start VDO device. (VDO error %d, message %s)",
+ result,
+ ti->error);
+ vdo_destroy(vdo);
+ return result;
+ }
+
+ set_device_config(ti, vdo, config);
+ vdo->device_config = config;
+ return VDO_SUCCESS;
+}
+
+/* Implements vdo_filter_t. */
+static bool __must_check vdo_is_named(struct vdo *vdo, const void *context)
+{
+ struct dm_target *ti = vdo->device_config->owning_target;
+ const char *device_name = vdo_get_device_name(ti);
+
+ return strcmp(device_name, (const char *) context) == 0;
+}
+
+/**
+ * get_bit_array_size() - Return the number of bytes needed to store a bit array of the specified
+ * capacity in an array of unsigned longs.
+ * @bit_count: The number of bits the array must hold.
+ *
+ * Return: the number of bytes needed for the array representation.
+ */
+static size_t get_bit_array_size(unsigned int bit_count)
+{
+ /* Round up to a multiple of the word size and convert to a byte count. */
+ return (BITS_TO_LONGS(bit_count) * sizeof(unsigned long));
+}
+
+/**
+ * grow_bit_array() - Re-allocate the bitmap word array so there will more instance numbers that
+ * can be allocated.
+ *
+ * Since the array is initially NULL, this also initializes the array the first time we allocate an
+ * instance number.
+ *
+ * Return: UDS_SUCCESS or an error code from the allocation
+ */
+static int grow_bit_array(void)
+{
+ unsigned int new_count =
+ max(instances.bit_count + BIT_COUNT_INCREMENT, (unsigned int) BIT_COUNT_MINIMUM);
+ unsigned long *new_words;
+ int result;
+
+ result = uds_reallocate_memory(instances.words,
+ get_bit_array_size(instances.bit_count),
+ get_bit_array_size(new_count),
+ "instance number bit array",
+ &new_words);
+ if (result != UDS_SUCCESS)
+ return result;
+
+ instances.bit_count = new_count;
+ instances.words = new_words;
+ return UDS_SUCCESS;
+}
+
+/**
+ * allocate_instance() - Allocate an instance number.
+ * @instance_ptr: A point to hold the instance number
+ *
+ * Return: UDS_SUCCESS or an error code
+ *
+ * This function must be called while holding the instances lock.
+ */
+static int allocate_instance(unsigned int *instance_ptr)
+{
+ unsigned int instance;
+ int result;
+
+ /* If there are no unallocated instances, grow the bit array. */
+ if (instances.count >= instances.bit_count) {
+ result = grow_bit_array();
+ if (result != UDS_SUCCESS)
+ return result;
+ }
+
+ /*
+ * There must be a zero bit somewhere now. Find it, starting just after the last instance
+ * allocated.
+ */
+ instance = find_next_zero_bit(instances.words,
+ instances.bit_count,
+ instances.next);
+ if (instance >= instances.bit_count) {
+ /* Nothing free after next, so wrap around to instance zero. */
+ instance = find_first_zero_bit(instances.words, instances.bit_count);
+ result = ASSERT(instance < instances.bit_count, "impossibly, no zero bit found");
+ if (result != UDS_SUCCESS)
+ return result;
+ }
+
+ __set_bit(instance, instances.words);
+ instances.count++;
+ instances.next = instance + 1;
+ *instance_ptr = instance;
+ return UDS_SUCCESS;
+}
+
+static int construct_new_vdo_registered(struct dm_target *ti,
+ unsigned int argc,
+ char **argv,
+ unsigned int instance)
+{
+ int result;
+ struct device_config *config;
+
+ result = parse_device_config(argc, argv, ti, &config);
+ if (result != VDO_SUCCESS) {
+ uds_log_error_strerror(result, "parsing failed: %s", ti->error);
+ release_instance(instance);
+ return -EINVAL;
+ }
+
+ /* Beyond this point, the instance number will be cleaned up for us if needed */
+ result = vdo_initialize(ti, instance, config);
+ if (result != VDO_SUCCESS) {
+ release_instance(instance);
+ free_device_config(config);
+ return vdo_map_to_system_error(result);
+ }
+
+ return VDO_SUCCESS;
+}
+
+static int construct_new_vdo(struct dm_target *ti, unsigned int argc, char **argv)
+{
+ int result;
+ unsigned int instance;
+ struct registered_thread instance_thread;
+
+ mutex_lock(&instances_lock);
+ result = allocate_instance(&instance);
+ mutex_unlock(&instances_lock);
+ if (result != VDO_SUCCESS)
+ return -ENOMEM;
+
+ uds_register_thread_device_id(&instance_thread, &instance);
+ result = construct_new_vdo_registered(ti, argc, argv, instance);
+ uds_unregister_thread_device_id();
+ return result;
+}
+
+/**
+ * check_may_grow_physical() - Callback to check that we're not in recovery mode, used in
+ * vdo_prepare_to_grow_physical().
+ * @completion: The admin completion.
+ */
+static void check_may_grow_physical(struct vdo_completion *completion)
+{
+ struct vdo *vdo = completion->vdo;
+
+ assert_admin_phase_thread(vdo, __func__);
+
+ /* These checks can only be done from a vdo thread. */
+ if (vdo_is_read_only(vdo))
+ vdo_set_completion_result(completion, VDO_READ_ONLY);
+
+ if (vdo_in_recovery_mode(vdo))
+ vdo_set_completion_result(completion, VDO_RETRY_AFTER_REBUILD);
+
+ finish_operation_callback(completion);
+}
+
+static block_count_t get_partition_size(struct layout *layout, enum partition_id id)
+{
+ return vdo_get_known_partition(layout, id)->count;
+}
+
+/**
+ * grow_layout() - Make the layout for growing a vdo.
+ * @vdo: The vdo preparing to grow.
+ * @old_size: The current size of the vdo.
+ * @new_size: The size to which the vdo will be grown.
+ *
+ * Return: VDO_SUCCESS or an error code.
+ */
+static int grow_layout(struct vdo *vdo, block_count_t old_size, block_count_t new_size)
+{
+ int result;
+ block_count_t min_new_size;
+
+ if (vdo->next_layout.size == new_size)
+ /* We are already prepared to grow to the new size, so we're done. */
+ return VDO_SUCCESS;
+
+ /* Make a copy completion if there isn't one */
+ if (vdo->partition_copier == NULL) {
+ vdo->partition_copier = dm_kcopyd_client_create(NULL);
+ if (vdo->partition_copier == NULL)
+ return -ENOMEM;
+ }
+
+ /* Free any unused preparation. */
+ vdo_uninitialize_layout(&vdo->next_layout);
+
+ /*
+ * Make a new layout with the existing partition sizes for everything but the slab depot
+ * partition.
+ */
+ result = vdo_initialize_layout(new_size,
+ vdo->layout.start,
+ get_partition_size(&vdo->layout, VDO_BLOCK_MAP_PARTITION),
+ get_partition_size(&vdo->layout,
+ VDO_RECOVERY_JOURNAL_PARTITION),
+ get_partition_size(&vdo->layout,
+ VDO_SLAB_SUMMARY_PARTITION),
+ &vdo->next_layout);
+ if (result != VDO_SUCCESS) {
+ dm_kcopyd_client_destroy(UDS_FORGET(vdo->partition_copier));
+ return result;
+ }
+
+ /* Ensure the new journal and summary are entirely within the added blocks. */
+ min_new_size = (old_size +
+ get_partition_size(&vdo->next_layout, VDO_SLAB_SUMMARY_PARTITION) +
+ get_partition_size(&vdo->next_layout, VDO_RECOVERY_JOURNAL_PARTITION));
+ if (min_new_size > new_size) {
+ /* Copying the journal and summary would destroy some old metadata. */
+ vdo_uninitialize_layout(&vdo->next_layout);
+ dm_kcopyd_client_destroy(UDS_FORGET(vdo->partition_copier));
+ return VDO_INCREMENT_TOO_SMALL;
+ }
+
+ return VDO_SUCCESS;
+}
+
+static int prepare_to_grow_physical(struct vdo *vdo, block_count_t new_physical_blocks)
+{
+ int result;
+ block_count_t current_physical_blocks = vdo->states.vdo.config.physical_blocks;
+
+ uds_log_info("Preparing to resize physical to %llu",
+ (unsigned long long) new_physical_blocks);
+ ASSERT_LOG_ONLY((new_physical_blocks > current_physical_blocks),
+ "New physical size is larger than current physical size");
+ result = perform_admin_operation(vdo,
+ PREPARE_GROW_PHYSICAL_PHASE_START,
+ check_may_grow_physical,
+ finish_operation_callback,
+ "prepare grow-physical");
+ if (result != VDO_SUCCESS)
+ return result;
+
+ result = grow_layout(vdo, current_physical_blocks, new_physical_blocks);
+ if (result != VDO_SUCCESS)
+ return result;
+
+ result = vdo_prepare_to_grow_slab_depot(vdo->depot,
+ vdo_get_known_partition(&vdo->next_layout,
+ VDO_SLAB_DEPOT_PARTITION));
+ if (result != VDO_SUCCESS) {
+ vdo_uninitialize_layout(&vdo->next_layout);
+ return result;
+ }
+
+ uds_log_info("Done preparing to resize physical");
+ return VDO_SUCCESS;
+}
+
+/**
+ * validate_new_device_config() - Check whether a new device config represents a valid modification
+ * to an existing config.
+ * @to_validate: The new config to validate.
+ * @config: The existing config.
+ * @may_grow: Set to true if growing the logical and physical size of the vdo is currently
+ * permitted.
+ * @error_ptr: A pointer to hold the reason for any error.
+ *
+ * Return: VDO_SUCCESS or an error.
+ */
+static int validate_new_device_config(struct device_config *to_validate,
+ struct device_config *config,
+ bool may_grow,
+ char **error_ptr)
+{
+ if (to_validate->owning_target->begin != config->owning_target->begin) {
+ *error_ptr = "Starting sector cannot change";
+ return VDO_PARAMETER_MISMATCH;
+ }
+
+ if (to_validate->logical_block_size != config->logical_block_size) {
+ *error_ptr = "Logical block size cannot change";
+ return VDO_PARAMETER_MISMATCH;
+ }
+
+ if (to_validate->logical_blocks < config->logical_blocks) {
+ *error_ptr = "Can't shrink VDO logical size";
+ return VDO_PARAMETER_MISMATCH;
+ }
+
+ if (to_validate->cache_size != config->cache_size) {
+ *error_ptr = "Block map cache size cannot change";
+ return VDO_PARAMETER_MISMATCH;
+ }
+
+ if (to_validate->block_map_maximum_age != config->block_map_maximum_age) {
+ *error_ptr = "Block map maximum age cannot change";
+ return VDO_PARAMETER_MISMATCH;
+ }
+
+ if (memcmp(&to_validate->thread_counts,
+ &config->thread_counts,
+ sizeof(struct thread_count_config)) != 0) {
+ *error_ptr = "Thread configuration cannot change";
+ return VDO_PARAMETER_MISMATCH;
+ }
+
+ if (to_validate->physical_blocks < config->physical_blocks) {
+ *error_ptr = "Removing physical storage from a VDO is not supported";
+ return VDO_NOT_IMPLEMENTED;
+ }
+
+ if (!may_grow && (to_validate->physical_blocks > config->physical_blocks)) {
+ *error_ptr = "VDO physical size may not grow in current state";
+ return VDO_NOT_IMPLEMENTED;
+ }
+
+ return VDO_SUCCESS;
+}
+
+static int prepare_to_modify(struct dm_target *ti, struct device_config *config, struct vdo *vdo)
+{
+ int result;
+ bool may_grow = (vdo_get_admin_state(vdo) != VDO_ADMIN_STATE_PRE_LOADED);
+
+ result = validate_new_device_config(config, vdo->device_config, may_grow, &ti->error);
+ if (result != VDO_SUCCESS)
+ return -EINVAL;
+
+ if (config->logical_blocks > vdo->device_config->logical_blocks) {
+ block_count_t logical_blocks = vdo->states.vdo.config.logical_blocks;
+
+ uds_log_info("Preparing to resize logical to %llu",
+ (unsigned long long) config->logical_blocks);
+ ASSERT_LOG_ONLY((config->logical_blocks > logical_blocks),
+ "New logical size is larger than current size");
+
+ result = vdo_prepare_to_grow_block_map(vdo->block_map, config->logical_blocks);
+ if (result != VDO_SUCCESS) {
+ ti->error = "Device vdo_prepare_to_grow_logical failed";
+ return result;
+ }
+
+ uds_log_info("Done preparing to resize logical");
+ }
+
+ if (config->physical_blocks > vdo->device_config->physical_blocks) {
+ result = prepare_to_grow_physical(vdo, config->physical_blocks);
+ if (result != VDO_SUCCESS) {
+ if (result == VDO_PARAMETER_MISMATCH)
+ /*
+ * If we don't trap this case, vdo_map_to_system_error() will remap
+ * it to -EIO, which is misleading and ahistorical.
+ */
+ result = -EINVAL;
+
+ if (result == VDO_TOO_MANY_SLABS)
+ ti->error = "Device vdo_prepare_to_grow_physical failed (specified physical size too big based on formatted slab size)";
+ else
+ ti->error = "Device vdo_prepare_to_grow_physical failed";
+
+ return result;
+ }
+ }
+
+ if (strcmp(config->parent_device_name, vdo->device_config->parent_device_name) != 0) {
+ const char *device_name = vdo_get_device_name(config->owning_target);
+
+ uds_log_info("Updating backing device of %s from %s to %s",
+ device_name,
+ vdo->device_config->parent_device_name,
+ config->parent_device_name);
+ }
+
+ return VDO_SUCCESS;
+}
+
+static int update_existing_vdo(const char *device_name,
+ struct dm_target *ti,
+ unsigned int argc,
+ char **argv,
+ struct vdo *vdo)
+{
+ int result;
+ struct device_config *config;
+
+ result = parse_device_config(argc, argv, ti, &config);
+ if (result != VDO_SUCCESS)
+ return -EINVAL;
+
+ uds_log_info("preparing to modify device '%s'", device_name);
+ result = prepare_to_modify(ti, config, vdo);
+ if (result != VDO_SUCCESS) {
+ free_device_config(config);
+ return vdo_map_to_system_error(result);
+ }
+
+ set_device_config(ti, vdo, config);
+ return VDO_SUCCESS;
+}
+
+static int vdo_ctr(struct dm_target *ti, unsigned int argc, char **argv)
+{
+ int result;
+ struct registered_thread allocating_thread, instance_thread;
+ const char *device_name;
+ struct vdo *vdo;
+
+ uds_register_allocating_thread(&allocating_thread, NULL);
+ device_name = vdo_get_device_name(ti);
+ vdo = vdo_find_matching(vdo_is_named, (const void *) device_name);
+ if (vdo == NULL) {
+ result = construct_new_vdo(ti, argc, argv);
+ } else {
+ uds_register_thread_device_id(&instance_thread, &vdo->instance);
+ result = update_existing_vdo(device_name, ti, argc, argv, vdo);
+ uds_unregister_thread_device_id();
+ }
+
+ uds_unregister_allocating_thread();
+ return result;
+}
+
+static void vdo_dtr(struct dm_target *ti)
+{
+ struct device_config *config = ti->private;
+ struct vdo *vdo = UDS_FORGET(config->vdo);
+
+ list_del_init(&config->config_list);
+ if (list_empty(&vdo->device_config_list)) {
+ const char *device_name;
+
+ /* This was the last config referencing the VDO. Free it. */
+ unsigned int instance = vdo->instance;
+ struct registered_thread allocating_thread, instance_thread;
+
+ uds_register_thread_device_id(&instance_thread, &instance);
+ uds_register_allocating_thread(&allocating_thread, NULL);
+
+ device_name = vdo_get_device_name(ti);
+ uds_log_info("stopping device '%s'", device_name);
+ if (vdo->dump_on_shutdown)
+ vdo_dump_all(vdo, "device shutdown");
+
+ vdo_destroy(UDS_FORGET(vdo));
+ uds_log_info("device '%s' stopped", device_name);
+ uds_unregister_thread_device_id();
+ uds_unregister_allocating_thread();
+ release_instance(instance);
+ } else if (config == vdo->device_config) {
+ /*
+ * The VDO still references this config. Give it a reference to a config that isn't
+ * being destroyed.
+ */
+ vdo->device_config = list_first_entry(&vdo->device_config_list,
+ struct device_config,
+ config_list);
+ }
+
+ free_device_config(config);
+ ti->private = NULL;
+}
+
+static void vdo_presuspend(struct dm_target *ti)
+{
+ get_vdo_for_target(ti)->suspend_type =
+ (dm_noflush_suspending(ti) ? VDO_ADMIN_STATE_SUSPENDING : VDO_ADMIN_STATE_SAVING);
+}
+
+/**
+ * write_super_block_for_suspend() - Update the VDO state and save the super block.
+ * @completion: The admin completion
+ */
+static void write_super_block_for_suspend(struct vdo_completion *completion)
+{
+ struct vdo *vdo = completion->vdo;
+
+ switch (vdo_get_state(vdo)) {
+ case VDO_DIRTY:
+ case VDO_NEW:
+ vdo_set_state(vdo, VDO_CLEAN);
+ break;
+
+ case VDO_CLEAN:
+ case VDO_READ_ONLY_MODE:
+ case VDO_FORCE_REBUILD:
+ case VDO_RECOVERING:
+ case VDO_REBUILD_FOR_UPGRADE:
+ break;
+
+ case VDO_REPLAYING:
+ default:
+ vdo_continue_completion(completion, UDS_BAD_STATE);
+ return;
+ }
+
+ vdo_save_components(vdo, completion);
+}
+
+/**
+ * suspend_callback() - Callback to initiate a suspend, registered in vdo_postsuspend().
+ * @completion: The sub-task completion.
+ */
+static void suspend_callback(struct vdo_completion *completion)
+{
+ struct vdo *vdo = completion->vdo;
+ struct admin_state *state = &vdo->admin.state;
+ int result;
+
+ assert_admin_phase_thread(vdo, __func__);
+
+ switch (advance_phase(vdo)) {
+ case SUSPEND_PHASE_START:
+ if (vdo_get_admin_state_code(state)->quiescent)
+ /* Already suspended */
+ break;
+
+ vdo_continue_completion(completion, vdo_start_operation(state, vdo->suspend_type));
+ return;
+
+ case SUSPEND_PHASE_PACKER:
+ /*
+ * If the VDO was already resumed from a prior suspend while read-only, some of the
+ * components may not have been resumed. By setting a read-only error here, we
+ * guarantee that the result of this suspend will be VDO_READ_ONLY and not
+ * VDO_INVALID_ADMIN_STATE in that case.
+ */
+ if (vdo_in_read_only_mode(vdo))
+ vdo_set_completion_result(completion, VDO_READ_ONLY);
+
+ vdo_drain_packer(vdo->packer, completion);
+ return;
+
+ case SUSPEND_PHASE_DATA_VIOS:
+ drain_data_vio_pool(vdo->data_vio_pool, completion);
+ return;
+
+ case SUSPEND_PHASE_DEDUPE:
+ vdo_drain_hash_zones(vdo->hash_zones, completion);
+ return;
+
+ case SUSPEND_PHASE_FLUSHES:
+ vdo_drain_flusher(vdo->flusher, completion);
+ return;
+
+ case SUSPEND_PHASE_LOGICAL_ZONES:
+ /*
+ * Attempt to flush all I/O before completing post suspend work. We believe a
+ * suspended device is expected to have persisted all data written before the
+ * suspend, even if it hasn't been flushed yet.
+ */
+ result = vdo_synchronous_flush(vdo);
+ if (result != VDO_SUCCESS)
+ vdo_enter_read_only_mode(vdo, result);
+
+ vdo_drain_logical_zones(vdo->logical_zones,
+ vdo_get_admin_state_code(state),
+ completion);
+ return;
+
+ case SUSPEND_PHASE_BLOCK_MAP:
+ vdo_drain_block_map(vdo->block_map,
+ vdo_get_admin_state_code(state),
+ completion);
+ return;
+
+ case SUSPEND_PHASE_JOURNAL:
+ vdo_drain_recovery_journal(vdo->recovery_journal,
+ vdo_get_admin_state_code(state),
+ completion);
+ return;
+
+ case SUSPEND_PHASE_DEPOT:
+ vdo_drain_slab_depot(vdo->depot,
+ vdo_get_admin_state_code(state),
+ completion);
+ return;
+
+ case SUSPEND_PHASE_READ_ONLY_WAIT:
+ vdo_wait_until_not_entering_read_only_mode(completion);
+ return;
+
+ case SUSPEND_PHASE_WRITE_SUPER_BLOCK:
+ if (vdo_is_state_suspending(state) || (completion->result != VDO_SUCCESS))
+ /* If we didn't save the VDO or there was an error, we're done. */
+ break;
+
+ write_super_block_for_suspend(completion);
+ return;
+
+ case SUSPEND_PHASE_END:
+ break;
+
+ default:
+ vdo_set_completion_result(completion, UDS_BAD_STATE);
+ }
+
+ finish_operation_callback(completion);
+}
+
+static void vdo_postsuspend(struct dm_target *ti)
+{
+ struct vdo *vdo = get_vdo_for_target(ti);
+ struct registered_thread instance_thread;
+ const char *device_name;
+ int result;
+
+ uds_register_thread_device_id(&instance_thread, &vdo->instance);
+ device_name = vdo_get_device_name(vdo->device_config->owning_target);
+ uds_log_info("suspending device '%s'", device_name);
+
+ /*
+ * It's important to note any error here does not actually stop device-mapper from
+ * suspending the device. All this work is done post suspend.
+ */
+ result = perform_admin_operation(vdo,
+ SUSPEND_PHASE_START,
+ suspend_callback,
+ suspend_callback,
+ "suspend");
+
+ if ((result == VDO_SUCCESS) || (result == VDO_READ_ONLY)) {
+ /*
+ * Treat VDO_READ_ONLY as a success since a read-only suspension still leaves the
+ * VDO suspended.
+ */
+ uds_log_info("device '%s' suspended", device_name);
+ } else if (result == VDO_INVALID_ADMIN_STATE) {
+ uds_log_error("Suspend invoked while in unexpected state: %s",
+ vdo_get_admin_state(vdo)->name);
+ } else {
+ uds_log_error_strerror(result, "Suspend of device '%s' failed", device_name);
+ }
+
+ uds_unregister_thread_device_id();
+}
+
+/**
+ * was_new() - Check whether the vdo was new when it was loaded.
+ * @vdo: The vdo to query.
+ *
+ * Return: true if the vdo was new.
+ */
+static bool was_new(const struct vdo *vdo)
+{
+ return (vdo->load_state == VDO_NEW);
+}
+
+/**
+ * requires_repair() - Check whether a vdo requires recovery or rebuild.
+ * @vdo: The vdo to query.
+ *
+ * Return: true if the vdo must be repaired.
+ */
+static bool __must_check requires_repair(const struct vdo *vdo)
+{
+ switch (vdo_get_state(vdo)) {
+ case VDO_DIRTY:
+ case VDO_FORCE_REBUILD:
+ case VDO_REPLAYING:
+ case VDO_REBUILD_FOR_UPGRADE:
+ return true;
+
+ default:
+ return false;
+ }
+}
+
+/**
+ * get_load_type() - Determine how the slab depot was loaded.
+ * @vdo: The vdo.
+ *
+ * Return: How the depot was loaded.
+ */
+static enum slab_depot_load_type get_load_type(struct vdo *vdo)
+{
+ if (vdo_state_requires_read_only_rebuild(vdo->load_state))
+ return VDO_SLAB_DEPOT_REBUILD_LOAD;
+
+ if (vdo_state_requires_recovery(vdo->load_state))
+ return VDO_SLAB_DEPOT_RECOVERY_LOAD;
+
+ return VDO_SLAB_DEPOT_NORMAL_LOAD;
+}
+
+/**
+ * vdo_initialize_kobjects() - Initialize the vdo sysfs directory.
+ * @vdo: The vdo being initialized.
+ *
+ * Return: VDO_SUCCESS or an error code.
+ */
+static int vdo_initialize_kobjects(struct vdo *vdo)
+{
+ int result;
+ struct dm_target *target = vdo->device_config->owning_target;
+ struct mapped_device *md = dm_table_get_md(target->table);
+
+ kobject_init(&vdo->vdo_directory, &vdo_directory_type);
+ vdo->sysfs_added = true;
+ result = kobject_add(&vdo->vdo_directory, &disk_to_dev(dm_disk(md))->kobj, "vdo");
+ if (result != 0)
+ return VDO_CANT_ADD_SYSFS_NODE;
+
+ result = vdo_add_dedupe_index_sysfs(vdo->hash_zones);
+ if (result != 0)
+ return VDO_CANT_ADD_SYSFS_NODE;
+
+ return vdo_add_sysfs_stats_dir(vdo);
+}
+
+/**
+ * load_callback() - Callback to do the destructive parts of loading a VDO.
+ * @completion: The sub-task completion.
+ */
+static void load_callback(struct vdo_completion *completion)
+{
+ struct vdo *vdo = completion->vdo;
+ int result;
+
+ assert_admin_phase_thread(vdo, __func__);
+
+ switch (advance_phase(vdo)) {
+ case LOAD_PHASE_START:
+ result = vdo_start_operation(&vdo->admin.state, VDO_ADMIN_STATE_LOADING);
+ if (result != VDO_SUCCESS) {
+ vdo_continue_completion(completion, result);
+ return;
+ }
+
+ /* Prepare the recovery journal for new entries. */
+ vdo_open_recovery_journal(vdo->recovery_journal, vdo->depot, vdo->block_map);
+ vdo_allow_read_only_mode_entry(completion);
+ return;
+
+ case LOAD_PHASE_STATS:
+ vdo_continue_completion(completion, vdo_initialize_kobjects(vdo));
+ return;
+
+ case LOAD_PHASE_LOAD_DEPOT:
+ if (vdo_is_read_only(vdo)) {
+ /*
+ * In read-only mode we don't use the allocator and it may not even be
+ * readable, so don't bother trying to load it.
+ */
+ vdo_set_completion_result(completion, VDO_READ_ONLY);
+ break;
+ }
+
+ if (requires_repair(vdo)) {
+ vdo_repair(completion);
+ return;
+ }
+
+ vdo_load_slab_depot(vdo->depot,
+ (was_new(vdo) ?
+ VDO_ADMIN_STATE_FORMATTING :
+ VDO_ADMIN_STATE_LOADING),
+ completion,
+ NULL);
+ return;
+
+ case LOAD_PHASE_MAKE_DIRTY:
+ vdo_set_state(vdo, VDO_DIRTY);
+ vdo_save_components(vdo, completion);
+ return;
+
+ case LOAD_PHASE_PREPARE_TO_ALLOCATE:
+ vdo_initialize_block_map_from_journal(vdo->block_map, vdo->recovery_journal);
+ vdo_prepare_slab_depot_to_allocate(vdo->depot, get_load_type(vdo), completion);
+ return;
+
+ case LOAD_PHASE_SCRUB_SLABS:
+ if (vdo_state_requires_recovery(vdo->load_state))
+ vdo_enter_recovery_mode(vdo);
+
+ vdo_scrub_all_unrecovered_slabs(vdo->depot, completion);
+ return;
+
+ case LOAD_PHASE_DATA_REDUCTION:
+ WRITE_ONCE(vdo->compressing, vdo->device_config->compression);
+ if (vdo->device_config->deduplication)
+ /*
+ * Don't try to load or rebuild the index first (and log scary error
+ * messages) if this is known to be a newly-formatted volume.
+ */
+ vdo_start_dedupe_index(vdo->hash_zones, was_new(vdo));
+
+ vdo->allocations_allowed = false;
+ fallthrough;
+
+ case LOAD_PHASE_FINISHED:
+ break;
+
+ case LOAD_PHASE_DRAIN_JOURNAL:
+ vdo_drain_recovery_journal(vdo->recovery_journal,
+ VDO_ADMIN_STATE_SAVING,
+ completion);
+ return;
+
+ case LOAD_PHASE_WAIT_FOR_READ_ONLY:
+ /* Avoid an infinite loop */
+ completion->error_handler = NULL;
+ vdo->admin.phase = LOAD_PHASE_FINISHED;
+ vdo_wait_until_not_entering_read_only_mode(completion);
+ return;
+
+ default:
+ vdo_set_completion_result(completion, UDS_BAD_STATE);
+ }
+
+ finish_operation_callback(completion);
+}
+
+/**
+ * handle_load_error() - Handle an error during the load operation.
+ * @completion: The admin completion.
+ *
+ * If at all possible, brings the vdo online in read-only mode. This handler is registered in
+ * vdo_preresume_registered().
+ */
+static void handle_load_error(struct vdo_completion *completion)
+{
+ struct vdo *vdo = completion->vdo;
+
+ if (vdo_requeue_completion_if_needed(completion, vdo->thread_config.admin_thread))
+ return;
+
+ if (vdo_state_requires_read_only_rebuild(vdo->load_state) &&
+ (vdo->admin.phase == LOAD_PHASE_MAKE_DIRTY)) {
+ uds_log_error_strerror(completion->result, "aborting load");
+ vdo->admin.phase = LOAD_PHASE_DRAIN_JOURNAL;
+ load_callback(UDS_FORGET(completion));
+ return;
+ }
+
+ uds_log_error_strerror(completion->result, "Entering read-only mode due to load error");
+ vdo->admin.phase = LOAD_PHASE_WAIT_FOR_READ_ONLY;
+ vdo_enter_read_only_mode(vdo, completion->result);
+ completion->result = VDO_READ_ONLY;
+ load_callback(completion);
+}
+
+/**
+ * write_super_block_for_resume() - Update the VDO state and save the super block.
+ * @completion: The admin completion
+ */
+static void write_super_block_for_resume(struct vdo_completion *completion)
+{
+ struct vdo *vdo = completion->vdo;
+
+ switch (vdo_get_state(vdo)) {
+ case VDO_CLEAN:
+ case VDO_NEW:
+ vdo_set_state(vdo, VDO_DIRTY);
+ vdo_save_components(vdo, completion);
+ return;
+
+ case VDO_DIRTY:
+ case VDO_READ_ONLY_MODE:
+ case VDO_FORCE_REBUILD:
+ case VDO_RECOVERING:
+ case VDO_REBUILD_FOR_UPGRADE:
+ /* No need to write the super block in these cases */
+ vdo_launch_completion(completion);
+ return;
+
+ case VDO_REPLAYING:
+ default:
+ vdo_continue_completion(completion, UDS_BAD_STATE);
+ }
+}
+
+/**
+ * resume_callback() - Callback to resume a VDO.
+ * @completion: The admin completion.
+ */
+static void resume_callback(struct vdo_completion *completion)
+{
+ struct vdo *vdo = completion->vdo;
+ int result;
+
+ assert_admin_phase_thread(vdo, __func__);
+
+ switch (advance_phase(vdo)) {
+ case RESUME_PHASE_START:
+ result = vdo_start_operation(&vdo->admin.state, VDO_ADMIN_STATE_RESUMING);
+ if (result != VDO_SUCCESS) {
+ vdo_continue_completion(completion, result);
+ return;
+ }
+
+ write_super_block_for_resume(completion);
+ return;
+
+ case RESUME_PHASE_ALLOW_READ_ONLY_MODE:
+ vdo_allow_read_only_mode_entry(completion);
+ return;
+
+ case RESUME_PHASE_DEDUPE:
+ vdo_resume_hash_zones(vdo->hash_zones, completion);
+ return;
+
+ case RESUME_PHASE_DEPOT:
+ vdo_resume_slab_depot(vdo->depot, completion);
+ return;
+
+ case RESUME_PHASE_JOURNAL:
+ vdo_resume_recovery_journal(vdo->recovery_journal, completion);
+ return;
+
+ case RESUME_PHASE_BLOCK_MAP:
+ vdo_resume_block_map(vdo->block_map, completion);
+ return;
+
+ case RESUME_PHASE_LOGICAL_ZONES:
+ vdo_resume_logical_zones(vdo->logical_zones, completion);
+ return;
+
+ case RESUME_PHASE_PACKER:
+ {
+ bool was_enabled = vdo_get_compressing(vdo);
+ bool enable = vdo->device_config->compression;
+
+ if (enable != was_enabled)
+ WRITE_ONCE(vdo->compressing, enable);
+ uds_log_info("compression is %s", (enable ? "enabled" : "disabled"));
+
+ vdo_resume_packer(vdo->packer, completion);
+ return;
+ }
+
+ case RESUME_PHASE_FLUSHER:
+ vdo_resume_flusher(vdo->flusher, completion);
+ return;
+
+ case RESUME_PHASE_DATA_VIOS:
+ resume_data_vio_pool(vdo->data_vio_pool, completion);
+ return;
+
+ case RESUME_PHASE_END:
+ break;
+
+ default:
+ vdo_set_completion_result(completion, UDS_BAD_STATE);
+ }
+
+ finish_operation_callback(completion);
+}
+
+/**
+ * grow_logical_callback() - Callback to initiate a grow logical.
+ * @completion: The admin completion.
+ *
+ * Registered in perform_grow_logical().
+ */
+static void grow_logical_callback(struct vdo_completion *completion)
+{
+ struct vdo *vdo = completion->vdo;
+ int result;
+
+ assert_admin_phase_thread(vdo, __func__);
+
+ switch (advance_phase(vdo)) {
+ case GROW_LOGICAL_PHASE_START:
+ if (vdo_is_read_only(vdo)) {
+ uds_log_error_strerror(VDO_READ_ONLY,
+ "Can't grow logical size of a read-only VDO");
+ vdo_set_completion_result(completion, VDO_READ_ONLY);
+ break;
+ }
+
+ result = vdo_start_operation(&vdo->admin.state,
+ VDO_ADMIN_STATE_SUSPENDED_OPERATION);
+ if (result != VDO_SUCCESS) {
+ vdo_continue_completion(completion, result);
+ return;
+ }
+
+ vdo->states.vdo.config.logical_blocks = vdo->block_map->next_entry_count;
+ vdo_save_components(vdo, completion);
+ return;
+
+ case GROW_LOGICAL_PHASE_GROW_BLOCK_MAP:
+ vdo_grow_block_map(vdo->block_map, completion);
+ return;
+
+ case GROW_LOGICAL_PHASE_END:
+ break;
+
+ case GROW_LOGICAL_PHASE_ERROR:
+ vdo_enter_read_only_mode(vdo, completion->result);
+ break;
+
+ default:
+ vdo_set_completion_result(completion, UDS_BAD_STATE);
+ }
+
+ finish_operation_callback(completion);
+}
+
+/**
+ * handle_logical_growth_error() - Handle an error during the grow physical process.
+ * @completion: The admin completion.
+ */
+static void handle_logical_growth_error(struct vdo_completion *completion)
+{
+ struct vdo *vdo = completion->vdo;
+
+ if (vdo->admin.phase == GROW_LOGICAL_PHASE_GROW_BLOCK_MAP) {
+ /*
+ * We've failed to write the new size in the super block, so set our in memory
+ * config back to the old size.
+ */
+ vdo->states.vdo.config.logical_blocks = vdo->block_map->entry_count;
+ vdo_abandon_block_map_growth(vdo->block_map);
+ }
+
+ vdo->admin.phase = GROW_LOGICAL_PHASE_ERROR;
+ grow_logical_callback(completion);
+}
+
+/**
+ * perform_grow_logical() - Grow the logical size of the vdo.
+ * @vdo: The vdo to grow.
+ * @new_logical_blocks: The size to which the vdo should be grown.
+ *
+ * Context: This method may only be called when the vdo has been suspended and must not be called
+ * from a base thread.
+ *
+ * Return: VDO_SUCCESS or an error.
+ */
+static int perform_grow_logical(struct vdo *vdo, block_count_t new_logical_blocks)
+{
+ int result;
+
+ if (vdo->device_config->logical_blocks == new_logical_blocks) {
+ /*
+ * A table was loaded for which we prepared to grow, but a table without that
+ * growth was what we are resuming with.
+ */
+ vdo_abandon_block_map_growth(vdo->block_map);
+ return VDO_SUCCESS;
+ }
+
+ uds_log_info("Resizing logical to %llu", (unsigned long long) new_logical_blocks);
+ if (vdo->block_map->next_entry_count != new_logical_blocks)
+ return VDO_PARAMETER_MISMATCH;
+
+ result = perform_admin_operation(vdo,
+ GROW_LOGICAL_PHASE_START,
+ grow_logical_callback,
+ handle_logical_growth_error,
+ "grow logical");
+ if (result != VDO_SUCCESS)
+ return result;
+
+ uds_log_info("Logical blocks now %llu", (unsigned long long) new_logical_blocks);
+ return VDO_SUCCESS;
+}
+
+static void copy_callback(int read_err, unsigned long write_err, void *context)
+{
+ struct vdo_completion *completion = context;
+ int result = (((read_err == 0) && (write_err == 0)) ? VDO_SUCCESS : -EIO);
+
+ vdo_continue_completion(completion, result);
+}
+
+static void
+partition_to_region(struct partition *partition, struct vdo *vdo, struct dm_io_region *region)
+{
+ physical_block_number_t pbn = partition->offset - vdo->geometry.bio_offset;
+
+ *region = (struct dm_io_region) {
+ .bdev = vdo_get_backing_device(vdo),
+ .sector = pbn * VDO_SECTORS_PER_BLOCK,
+ .count = partition->count * VDO_SECTORS_PER_BLOCK,
+ };
+}
+
+/**
+ * copy_partition() - Copy a partition from the location specified in the current layout to that in
+ * the next layout.
+ * @vdo: The vdo preparing to grow.
+ * @id: The ID of the partition to copy.
+ * @parent: The completion to notify when the copy is complete.
+ */
+static void copy_partition(struct vdo *vdo, enum partition_id id, struct vdo_completion *parent)
+{
+ struct dm_io_region read_region, write_regions[1];
+ struct partition *from = vdo_get_known_partition(&vdo->layout, id);
+ struct partition *to = vdo_get_known_partition(&vdo->next_layout, id);
+
+ partition_to_region(from, vdo, &read_region);
+ partition_to_region(to, vdo, &write_regions[0]);
+ dm_kcopyd_copy(vdo->partition_copier,
+ &read_region,
+ 1,
+ write_regions,
+ 0,
+ copy_callback,
+ parent);
+}
+
+/**
+ * grow_physical_callback() - Callback to initiate a grow physical.
+ * @completion: The admin completion.
+ *
+ * Registered in perform_grow_physical().
+ */
+static void grow_physical_callback(struct vdo_completion *completion)
+{
+ struct vdo *vdo = completion->vdo;
+ int result;
+
+ assert_admin_phase_thread(vdo, __func__);
+
+ switch (advance_phase(vdo)) {
+ case GROW_PHYSICAL_PHASE_START:
+ if (vdo_is_read_only(vdo)) {
+ uds_log_error_strerror(VDO_READ_ONLY,
+ "Can't grow physical size of a read-only VDO");
+ vdo_set_completion_result(completion, VDO_READ_ONLY);
+ break;
+ }
+
+ result = vdo_start_operation(&vdo->admin.state,
+ VDO_ADMIN_STATE_SUSPENDED_OPERATION);
+ if (result != VDO_SUCCESS) {
+ vdo_continue_completion(completion, result);
+ return;
+ }
+
+ /* Copy the journal into the new layout. */
+ copy_partition(vdo, VDO_RECOVERY_JOURNAL_PARTITION, completion);
+ return;
+
+ case GROW_PHYSICAL_PHASE_COPY_SUMMARY:
+ copy_partition(vdo, VDO_SLAB_SUMMARY_PARTITION, completion);
+ return;
+
+ case GROW_PHYSICAL_PHASE_UPDATE_COMPONENTS:
+ vdo_uninitialize_layout(&vdo->layout);
+ vdo->layout = vdo->next_layout;
+ UDS_FORGET(vdo->next_layout.head);
+ vdo->states.vdo.config.physical_blocks = vdo->layout.size;
+ vdo_update_slab_depot_size(vdo->depot);
+ vdo_save_components(vdo, completion);
+ return;
+
+ case GROW_PHYSICAL_PHASE_USE_NEW_SLABS:
+ vdo_use_new_slabs(vdo->depot, completion);
+ return;
+
+ case GROW_PHYSICAL_PHASE_END:
+ vdo->depot->summary_origin =
+ vdo_get_known_partition(&vdo->layout, VDO_SLAB_SUMMARY_PARTITION)->offset;
+ vdo->recovery_journal->origin =
+ vdo_get_known_partition(&vdo->layout,
+ VDO_RECOVERY_JOURNAL_PARTITION)->offset;
+ break;
+
+ case GROW_PHYSICAL_PHASE_ERROR:
+ vdo_enter_read_only_mode(vdo, completion->result);
+ break;
+
+ default:
+ vdo_set_completion_result(completion, UDS_BAD_STATE);
+ }
+
+ vdo_uninitialize_layout(&vdo->next_layout);
+ finish_operation_callback(completion);
+}
+
+/**
+ * handle_physical_growth_error() - Handle an error during the grow physical process.
+ * @completion: The sub-task completion.
+ */
+static void handle_physical_growth_error(struct vdo_completion *completion)
+{
+ completion->vdo->admin.phase = GROW_PHYSICAL_PHASE_ERROR;
+ grow_physical_callback(completion);
+}
+
+/**
+ * perform_grow_physical() - Grow the physical size of the vdo.
+ * @vdo: The vdo to resize.
+ * @new_physical_blocks: The new physical size in blocks.
+ *
+ * Context: This method may only be called when the vdo has been suspended and must not be called
+ * from a base thread.
+ *
+ * Return: VDO_SUCCESS or an error.
+ */
+static int perform_grow_physical(struct vdo *vdo, block_count_t new_physical_blocks)
+{
+ int result;
+ block_count_t new_depot_size, prepared_depot_size;
+ block_count_t old_physical_blocks = vdo->states.vdo.config.physical_blocks;
+
+ /* Skip any noop grows. */
+ if (old_physical_blocks == new_physical_blocks)
+ return VDO_SUCCESS;
+
+ if (new_physical_blocks != vdo->next_layout.size) {
+ /*
+ * Either the VDO isn't prepared to grow, or it was prepared to grow to a different
+ * size. Doing this check here relies on the fact that the call to this method is
+ * done under the dmsetup message lock.
+ */
+ vdo_uninitialize_layout(&vdo->next_layout);
+ vdo_abandon_new_slabs(vdo->depot);
+ return VDO_PARAMETER_MISMATCH;
+ }
+
+ /* Validate that we are prepared to grow appropriately. */
+ new_depot_size =
+ vdo_get_known_partition(&vdo->next_layout, VDO_SLAB_DEPOT_PARTITION)->count;
+ prepared_depot_size = (vdo->depot->new_slabs == NULL) ? 0 : vdo->depot->new_size;
+ if (prepared_depot_size != new_depot_size)
+ return VDO_PARAMETER_MISMATCH;
+
+ result = perform_admin_operation(vdo,
+ GROW_PHYSICAL_PHASE_START,
+ grow_physical_callback,
+ handle_physical_growth_error,
+ "grow physical");
+ if (result != VDO_SUCCESS)
+ return result;
+
+ uds_log_info("Physical block count was %llu, now %llu",
+ (unsigned long long) old_physical_blocks,
+ (unsigned long long) new_physical_blocks);
+ return VDO_SUCCESS;
+}
+
+/**
+ * apply_new_vdo_configuration() - Attempt to make any configuration changes from the table being
+ * resumed.
+ * @vdo: The vdo being resumed.
+ * @config: The new device configuration derived from the table with which the vdo is being
+ * resumed.
+ *
+ * Return: VDO_SUCCESS or an error.
+ */
+static int __must_check apply_new_vdo_configuration(struct vdo *vdo, struct device_config *config)
+{
+ int result;
+
+ result = perform_grow_logical(vdo, config->logical_blocks);
+ if (result != VDO_SUCCESS) {
+ uds_log_error("grow logical operation failed, result = %d", result);
+ return result;
+ }
+
+ result = perform_grow_physical(vdo, config->physical_blocks);
+ if (result != VDO_SUCCESS)
+ uds_log_error("resize operation failed, result = %d", result);
+
+ return result;
+}
+
+static int vdo_preresume_registered(struct dm_target *ti, struct vdo *vdo)
+{
+ struct device_config *config = ti->private;
+ const char *device_name = vdo_get_device_name(ti);
+ block_count_t backing_blocks;
+ int result;
+
+ backing_blocks = get_underlying_device_block_count(vdo);
+ if (backing_blocks < config->physical_blocks) {
+ /* FIXME: can this still happen? */
+ uds_log_error("resume of device '%s' failed: backing device has %llu blocks but VDO physical size is %llu blocks",
+ device_name,
+ (unsigned long long) backing_blocks,
+ (unsigned long long) config->physical_blocks);
+ return -EINVAL;
+ }
+
+ if (vdo_get_admin_state(vdo) == VDO_ADMIN_STATE_PRE_LOADED) {
+ uds_log_info("starting device '%s'", device_name);
+ result = perform_admin_operation(vdo,
+ LOAD_PHASE_START,
+ load_callback,
+ handle_load_error,
+ "load");
+ if ((result != VDO_SUCCESS) && (result != VDO_READ_ONLY)) {
+ /*
+ * Something has gone very wrong. Make sure everything has drained and
+ * leave the device in an unresumable state.
+ */
+ uds_log_error_strerror(result,
+ "Start failed, could not load VDO metadata");
+ vdo->suspend_type = VDO_ADMIN_STATE_STOPPING;
+ perform_admin_operation(vdo,
+ SUSPEND_PHASE_START,
+ suspend_callback,
+ suspend_callback,
+ "suspend");
+ return result;
+ }
+
+ /* Even if the VDO is read-only, it is now able to handle read requests. */
+ uds_log_info("device '%s' started", device_name);
+ }
+
+ uds_log_info("resuming device '%s'", device_name);
+
+ /* If this fails, the VDO was not in a state to be resumed. This should never happen. */
+ result = apply_new_vdo_configuration(vdo, config);
+ BUG_ON(result == VDO_INVALID_ADMIN_STATE);
+
+ /*
+ * Now that we've tried to modify the vdo, the new config *is* the config, whether the
+ * modifications worked or not.
+ */
+ vdo->device_config = config;
+
+ /*
+ * Any error here is highly unexpected and the state of the vdo is questionable, so we mark
+ * it read-only in memory. Because we are suspended, the read-only state will not be
+ * written to disk.
+ */
+ if (result != VDO_SUCCESS) {
+ uds_log_error_strerror(result,
+ "Commit of modifications to device '%s' failed",
+ device_name);
+ vdo_enter_read_only_mode(vdo, result);
+ return result;
+ }
+
+ if (vdo_get_admin_state(vdo)->normal)
+ /* The VDO was just started, so we don't need to resume it. */
+ return VDO_SUCCESS;
+
+ result = perform_admin_operation(vdo,
+ RESUME_PHASE_START,
+ resume_callback,
+ resume_callback,
+ "resume");
+ BUG_ON(result == VDO_INVALID_ADMIN_STATE);
+ if (result == VDO_READ_ONLY)
+ /* Even if the vdo is read-only, it has still resumed. */
+ result = VDO_SUCCESS;
+
+ if (result != VDO_SUCCESS)
+ uds_log_error("resume of device '%s' failed with error: %d", device_name, result);
+
+ return result;
+}
+
+static int vdo_preresume(struct dm_target *ti)
+{
+ struct registered_thread instance_thread;
+ struct vdo *vdo = get_vdo_for_target(ti);
+ int result;
+
+ uds_register_thread_device_id(&instance_thread, &vdo->instance);
+ result = vdo_preresume_registered(ti, vdo);
+ if ((result == VDO_PARAMETER_MISMATCH) || (result == VDO_INVALID_ADMIN_STATE))
+ result = -EINVAL;
+ uds_unregister_thread_device_id();
+ return vdo_map_to_system_error(result);
+}
+
+static void vdo_resume(struct dm_target *ti)
+{
+ struct registered_thread instance_thread;
+
+ uds_register_thread_device_id(&instance_thread, &get_vdo_for_target(ti)->instance);
+ uds_log_info("device '%s' resumed", vdo_get_device_name(ti));
+ uds_unregister_thread_device_id();
+}
+
+/*
+ * If anything changes that affects how user tools will interact with vdo, update the version
+ * number and make sure documentation about the change is complete so tools can properly update
+ * their management code.
+ */
+static struct target_type vdo_target_bio = {
+ .features = DM_TARGET_SINGLETON,
+ .name = "vdo",
+ .version = { 8, 2, 0 },
+ .module = THIS_MODULE,
+ .ctr = vdo_ctr,
+ .dtr = vdo_dtr,
+ .io_hints = vdo_io_hints,
+ .iterate_devices = vdo_iterate_devices,
+ .map = vdo_map_bio,
+ .message = vdo_message,
+ .status = vdo_status,
+ .presuspend = vdo_presuspend,
+ .postsuspend = vdo_postsuspend,
+ .preresume = vdo_preresume,
+ .resume = vdo_resume,
+};
+
+static bool dm_registered;
+
+static void vdo_module_destroy(void)
+{
+ uds_log_debug("unloading");
+
+ if (dm_registered)
+ dm_unregister_target(&vdo_target_bio);
+
+ ASSERT_LOG_ONLY(instances.count == 0,
+ "should have no instance numbers still in use, but have %u",
+ instances.count);
+ UDS_FREE(instances.words);
+ memset(&instances, 0, sizeof(struct instance_tracker));
+
+ uds_log_info("unloaded version %s", CURRENT_VERSION);
+}
+
+static int __init vdo_init(void)
+{
+ int result = 0;
+
+ /*
+ * UDS module level initialization must be done first, as VDO initialization depends on it
+ */
+ uds_initialize_thread_device_registry();
+ uds_memory_init();
+ uds_init_sysfs();
+
+ vdo_initialize_device_registry_once();
+ uds_log_info("loaded version %s", CURRENT_VERSION);
+
+ /* Add VDO errors to the already existing set of errors in UDS. */
+ result = vdo_register_status_codes();
+ if (result != UDS_SUCCESS) {
+ uds_log_error("vdo_register_status_codes failed %d", result);
+ vdo_module_destroy();
+ return result;
+ }
+
+ result = dm_register_target(&vdo_target_bio);
+ if (result < 0) {
+ uds_log_error("dm_register_target failed %d", result);
+ vdo_module_destroy();
+ return result;
+ }
+ dm_registered = true;
+
+ return result;
+}
+
+static void __exit vdo_exit(void)
+{
+ vdo_module_destroy();
+ /*
+ * UDS module level exit processing must be done after all VDO module exit processing is
+ * complete.
+ */
+ uds_put_sysfs();
+ uds_memory_exit();
+}
+
+module_init(vdo_init);
+module_exit(vdo_exit);
+
+MODULE_DESCRIPTION(DM_NAME " target for transparent deduplication");
+MODULE_AUTHOR("Red Hat, Inc.");
+MODULE_LICENSE("GPL");
+MODULE_VERSION(CURRENT_VERSION);
This adds the dm-vdo target. Signed-off-by: J. corwin Coburn <corwin@redhat.com> --- drivers/md/dm-vdo-target.c | 2983 ++++++++++++++++++++++++++++++++++++ 1 file changed, 2983 insertions(+) create mode 100644 drivers/md/dm-vdo-target.c