* the device.
*/
bool fail_io:1;
+
+ /*
+ * These structures are used when loading metadata. They're too
+ * big to put on the stack.
+ */
+ struct dm_array_cursor mapping_cursor;
+ struct dm_array_cursor hint_cursor;
};
/*-------------------------------------------------------------------
hints_array_initialized(cmd);
}
-static int __load_mapping(void *context, uint64_t cblock, void *leaf)
+static int __load_mapping(struct dm_cache_metadata *cmd,
+ uint64_t cb, bool hints_valid,
+ struct dm_array_cursor *mapping_cursor,
+ struct dm_array_cursor *hint_cursor,
+ load_mapping_fn fn, void *context)
{
int r = 0;
- bool dirty;
- __le64 value;
- __le32 hint_value = 0;
+
+ __le64 mapping;
+ __le32 hint = 0;
+
+ __le64 *mapping_value_le;
+ __le32 *hint_value_le;
+
dm_oblock_t oblock;
unsigned flags;
- struct thunk *thunk = context;
- struct dm_cache_metadata *cmd = thunk->cmd;
- memcpy(&value, leaf, sizeof(value));
- unpack_value(value, &oblock, &flags);
+ dm_array_cursor_get_value(mapping_cursor, (void **) &mapping_value_le);
+ memcpy(&mapping, mapping_value_le, sizeof(mapping));
+ unpack_value(mapping, &oblock, &flags);
if (flags & M_VALID) {
- if (thunk->hints_valid) {
- r = dm_array_get_value(&cmd->hint_info, cmd->hint_root,
- cblock, &hint_value);
- if (r && r != -ENODATA)
- return r;
+ if (hints_valid) {
+ dm_array_cursor_get_value(hint_cursor, (void **) &hint_value_le);
+ memcpy(&hint, hint_value_le, sizeof(hint));
}
- dirty = thunk->respect_dirty_flags ? (flags & M_DIRTY) : true;
- r = thunk->fn(thunk->context, oblock, to_cblock(cblock),
- dirty, le32_to_cpu(hint_value), thunk->hints_valid);
+ r = fn(context, oblock, to_cblock(cb), flags & M_DIRTY,
+ le32_to_cpu(hint), hints_valid);
+ if (r)
+ DMERR("policy couldn't load cblock");
}
return r;
struct dm_cache_policy *policy,
load_mapping_fn fn, void *context)
{
- struct thunk thunk;
+ int r;
+ uint64_t cb;
+
+ bool hints_valid = hints_array_available(cmd, policy);
+
+ if (from_cblock(cmd->cache_blocks) == 0)
+ /* Nothing to do */
+ return 0;
+
+ r = dm_array_cursor_begin(&cmd->info, cmd->root, &cmd->mapping_cursor);
+ if (r)
+ return r;
- thunk.fn = fn;
- thunk.context = context;
+ if (hints_valid) {
+ r = dm_array_cursor_begin(&cmd->hint_info, cmd->hint_root, &cmd->hint_cursor);
+ if (r) {
+ dm_array_cursor_end(&cmd->mapping_cursor);
+ return r;
+ }
+ }
+
+ for (cb = 0; ; cb++) {
+ r = __load_mapping(cmd, cb, hints_valid,
+ &cmd->mapping_cursor, &cmd->hint_cursor,
+ fn, context);
+ if (r)
+ goto out;
+
+ /*
+ * We need to break out before we move the cursors.
+ */
+ if (cb >= (from_cblock(cmd->cache_blocks) - 1))
+ break;
- thunk.cmd = cmd;
- thunk.respect_dirty_flags = cmd->clean_when_opened;
- thunk.hints_valid = hints_array_available(cmd, policy);
+ r = dm_array_cursor_next(&cmd->mapping_cursor);
+ if (r) {
+ DMERR("dm_array_cursor_next for mapping failed");
+ goto out;
+ }
- return dm_array_walk(&cmd->info, cmd->root, __load_mapping, &thunk);
+ if (hints_valid) {
+ r = dm_array_cursor_next(&cmd->hint_cursor);
+ if (r) {
+ DMERR("dm_array_cursor_next for hint failed");
+ goto out;
+ }
+ }
+ }
+out:
+ dm_array_cursor_end(&cmd->mapping_cursor);
+ if (hints_valid)
+ dm_array_cursor_end(&cmd->hint_cursor);
+
+ return r;
}
int dm_cache_load_mappings(struct dm_cache_metadata *cmd,
/*----------------------------------------------------------------*/
-static int begin_hints(struct dm_cache_metadata *cmd, struct dm_cache_policy *policy)
+static int get_hint(uint32_t index, void *value_le, void *context)
+{
+ uint32_t value;
+ struct dm_cache_policy *policy = context;
+
+ value = policy_get_hint(policy, to_cblock(index));
+ *((__le32 *) value_le) = cpu_to_le32(value);
+
+ return 0;
+}
+
+/*
+ * It's quicker to always delete the hint array, and recreate with
+ * dm_array_new().
+ */
+static int write_hints(struct dm_cache_metadata *cmd, struct dm_cache_policy *policy)
{
int r;
- __le32 value;
size_t hint_size;
const char *policy_name = dm_cache_policy_get_name(policy);
const unsigned *policy_version = dm_cache_policy_get_version(policy);
(strlen(policy_name) > sizeof(cmd->policy_name) - 1))
return -EINVAL;
- if (!policy_unchanged(cmd, policy)) {
- strncpy(cmd->policy_name, policy_name, sizeof(cmd->policy_name));
- memcpy(cmd->policy_version, policy_version, sizeof(cmd->policy_version));
-
- hint_size = dm_cache_policy_get_hint_size(policy);
- if (!hint_size)
- return 0; /* short-circuit hints initialization */
- cmd->policy_hint_size = hint_size;
+ strncpy(cmd->policy_name, policy_name, sizeof(cmd->policy_name));
+ memcpy(cmd->policy_version, policy_version, sizeof(cmd->policy_version));
- if (cmd->hint_root) {
- r = dm_array_del(&cmd->hint_info, cmd->hint_root);
- if (r)
- return r;
- }
+ hint_size = dm_cache_policy_get_hint_size(policy);
+ if (!hint_size)
+ return 0; /* short-circuit hints initialization */
+ cmd->policy_hint_size = hint_size;
- r = dm_array_empty(&cmd->hint_info, &cmd->hint_root);
+ if (cmd->hint_root) {
+ r = dm_array_del(&cmd->hint_info, cmd->hint_root);
if (r)
return r;
-
- value = cpu_to_le32(0);
- __dm_bless_for_disk(&value);
- r = dm_array_resize(&cmd->hint_info, cmd->hint_root, 0,
- from_cblock(cmd->cache_blocks),
- &value, &cmd->hint_root);
- if (r)
- return r;
- }
-
- return 0;
-}
-
-static int save_hint(void *context, dm_cblock_t cblock, dm_oblock_t oblock, uint32_t hint)
-{
- struct dm_cache_metadata *cmd = context;
- __le32 value = cpu_to_le32(hint);
- int r;
-
- __dm_bless_for_disk(&value);
-
- r = dm_array_set_value(&cmd->hint_info, cmd->hint_root,
- from_cblock(cblock), &value, &cmd->hint_root);
- cmd->changed = true;
-
- return r;
-}
-
-static int write_hints(struct dm_cache_metadata *cmd, struct dm_cache_policy *policy)
-{
- int r;
-
- r = begin_hints(cmd, policy);
- if (r) {
- DMERR("begin_hints failed");
- return r;
}
- return policy_walk_mappings(policy, save_hint, cmd);
+ return dm_array_new(&cmd->hint_info, &cmd->hint_root,
+ from_cblock(cmd->cache_blocks),
+ get_hint, policy);
}
int dm_cache_write_hints(struct dm_cache_metadata *cmd, struct dm_cache_policy *policy)
projects / cascardo / linux.git / blobdiff