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-rw-r--r--drivers/md/dm-ioctl.c103
1 files changed, 103 insertions, 0 deletions
diff --git a/drivers/md/dm-ioctl.c b/drivers/md/dm-ioctl.c
index f666778ad237..c740153b4e52 100644
--- a/drivers/md/dm-ioctl.c
+++ b/drivers/md/dm-ioctl.c
@@ -2018,3 +2018,106 @@ out:
return r;
}
+
+
+/**
+ * dm_early_create - create a mapped device in early boot.
+ *
+ * @dmi: Contains main information of the device mapping to be created.
+ * @spec_array: array of pointers to struct dm_target_spec. Describes the
+ * mapping table of the device.
+ * @target_params_array: array of strings with the parameters to a specific
+ * target.
+ *
+ * Instead of having the struct dm_target_spec and the parameters for every
+ * target embedded at the end of struct dm_ioctl (as performed in a normal
+ * ioctl), pass them as arguments, so the caller doesn't need to serialize them.
+ * The size of the spec_array and target_params_array is given by
+ * @dmi->target_count.
+ * This function is supposed to be called in early boot, so locking mechanisms
+ * to protect against concurrent loads are not required.
+ */
+int __init dm_early_create(struct dm_ioctl *dmi,
+ struct dm_target_spec **spec_array,
+ char **target_params_array)
+{
+ int r, m = DM_ANY_MINOR;
+ struct dm_table *t, *old_map;
+ struct mapped_device *md;
+ unsigned int i;
+
+ if (!dmi->target_count)
+ return -EINVAL;
+
+ r = check_name(dmi->name);
+ if (r)
+ return r;
+
+ if (dmi->flags & DM_PERSISTENT_DEV_FLAG)
+ m = MINOR(huge_decode_dev(dmi->dev));
+
+ /* alloc dm device */
+ r = dm_create(m, &md);
+ if (r)
+ return r;
+
+ /* hash insert */
+ r = dm_hash_insert(dmi->name, *dmi->uuid ? dmi->uuid : NULL, md);
+ if (r)
+ goto err_destroy_dm;
+
+ /* alloc table */
+ r = dm_table_create(&t, get_mode(dmi), dmi->target_count, md);
+ if (r)
+ goto err_destroy_dm;
+
+ /* add targets */
+ for (i = 0; i < dmi->target_count; i++) {
+ r = dm_table_add_target(t, spec_array[i]->target_type,
+ (sector_t) spec_array[i]->sector_start,
+ (sector_t) spec_array[i]->length,
+ target_params_array[i]);
+ if (r) {
+ DMWARN("error adding target to table");
+ goto err_destroy_table;
+ }
+ }
+
+ /* finish table */
+ r = dm_table_complete(t);
+ if (r)
+ goto err_destroy_table;
+
+ md->type = dm_table_get_type(t);
+ /* setup md->queue to reflect md's type (may block) */
+ r = dm_setup_md_queue(md, t);
+ if (r) {
+ DMWARN("unable to set up device queue for new table.");
+ goto err_destroy_table;
+ }
+
+ /* Set new map */
+ dm_suspend(md, 0);
+ old_map = dm_swap_table(md, t);
+ if (IS_ERR(old_map)) {
+ r = PTR_ERR(old_map);
+ goto err_destroy_table;
+ }
+ set_disk_ro(dm_disk(md), !!(dmi->flags & DM_READONLY_FLAG));
+
+ /* resume device */
+ r = dm_resume(md);
+ if (r)
+ goto err_destroy_table;
+
+ DMINFO("%s (%s) is ready", md->disk->disk_name, dmi->name);
+ dm_put(md);
+ return 0;
+
+err_destroy_table:
+ dm_table_destroy(t);
+err_destroy_dm:
+ dm_put(md);
+ dm_destroy(md);
+ return r;
+}