diff options
Diffstat (limited to 'drivers/md/dm-ioctl.c')
| -rw-r--r-- | drivers/md/dm-ioctl.c | 103 |
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; +} |