On 2020-06-04 18:38, Daejun Park wrote: > > + if (total_srgn_cnt != 0) { > > + dev_err(hba->dev, "ufshpb(%d) error total_subregion_count %d", > > + hpb->lun, total_srgn_cnt); > > + goto release_srgn_table; > > + } > > + > > + return 0; > > +release_srgn_table: > > + for (i = 0; i < rgn_idx; i++) { > > + rgn = rgn_table + i; > > + if (rgn->srgn_tbl) > > + kvfree(rgn->srgn_tbl); > > + }
> Please insert a blank line above goto labels as is done in most of the > kernel code. OK, I will fix it. > > +static struct device_attribute ufshpb_sysfs_entries[] = { > > + __ATTR(hit_count, 0444, ufshpb_sysfs_show_hit_cnt, NULL), > > + __ATTR(miss_count, 0444, ufshpb_sysfs_show_miss_cnt, NULL), > > + __ATTR(rb_noti_count, 0444, ufshpb_sysfs_show_rb_noti_cnt, NULL), > > + __ATTR(rb_active_count, 0444, ufshpb_sysfs_show_rb_active_cnt, NULL), > > + __ATTR(rb_inactive_count, 0444, ufshpb_sysfs_show_rb_inactive_cnt, > > + NULL), > > + __ATTR(map_req_count, 0444, ufshpb_sysfs_show_map_req_cnt, NULL), > > + __ATTR_NULL > > +}; > Please use __ATTR_RO() where appropriate. They are only readable attributes. So I changed the code to use __ATTR_RO. > > +static int ufshpb_create_sysfs(struct ufs_hba *hba, struct ufshpb_lu *hpb) > > +{ > > + struct device_attribute *attr; > > + int ret; > > + > > + device_initialize(&hpb->hpb_lu_dev); > > + > > + ufshpb_stat_init(hpb); > > + > > + hpb->hpb_lu_dev.parent = get_device(&hba->ufsf.hpb_dev); > > + hpb->hpb_lu_dev.release = ufshpb_dev_release; > > + dev_set_name(&hpb->hpb_lu_dev, "ufshpb_lu%d", hpb->lun); > > + > > + ret = device_add(&hpb->hpb_lu_dev); > > + if (ret) { > > + dev_err(hba->dev, "ufshpb(%d) device_add failed", > > + hpb->lun); > > + return -ENODEV; > > + } > > + > > + for (attr = ufshpb_sysfs_entries; attr->attr.name != NULL; attr++) { > > + if (device_create_file(&hpb->hpb_lu_dev, attr)) > > + dev_err(hba->dev, "ufshpb(%d) %s create file error\n", > > + hpb->lun, attr->attr.name); > > + } > > + > > + return 0; > > +} > This is the wrong way to create sysfs attributes. Please set the > 'groups' member of struct device instead of using a loop to create sysfs > attributes. The former approach is compatible with udev but the latter > approach is not. OK, I changed to create attributes without loop. > > +static void ufshpb_probe_async(void *data, async_cookie_t cookie) > > +{ > > + struct ufshpb_dev_info hpb_dev_info = { 0 }; > > + struct ufs_hba *hba = data; > > + char *desc_buf; > > + int ret; > > + > > + desc_buf = kzalloc(QUERY_DESC_MAX_SIZE, GFP_KERNEL); > > + if (!desc_buf) > > + goto release_desc_buf; > > + > > + ret = ufshpb_get_dev_info(hba, &hpb_dev_info, desc_buf); > > + if (ret) > > + goto release_desc_buf; > > + > > + /* > > + * Because HPB driver uses scsi_device data structure, > > + * we should wait at this point until finishing initialization of all > > + * scsi devices. Even if timeout occurs, HPB driver will search > > + * the scsi_device list on struct scsi_host (shost->__host list_head) > > + * and can find out HPB logical units in all scsi_devices > > + */ > > + wait_event_timeout(hba->ufsf.sdev_wait, > > + (atomic_read(&hba->ufsf.slave_conf_cnt) > > + == hpb_dev_info.num_lu), > > + SDEV_WAIT_TIMEOUT); > > + > > + dev_dbg(hba->dev, "ufshpb: slave count %d, lu count %d\n", > > + atomic_read(&hba->ufsf.slave_conf_cnt), hpb_dev_info.num_lu); > > + > > + ufshpb_scan_hpb_lu(hba, &hpb_dev_info, desc_buf); > > +release_desc_buf: > > + kfree(desc_buf); > > +} > What happens if two LUNs are added before the above code is woken up? > Will that perhaps cause the wait_event_timeout() call to wait forever? I don't think it is problem. I think that the wait_event_timeout() will check the condition before waiting. > > +static int ufshpb_probe(struct device *dev) > > +{ > > + struct ufs_hba *hba; > > + struct ufsf_feature_info *ufsf; > > + > > + if (dev->type != &ufshpb_dev_type) > > + return -ENODEV; > > + > > + ufsf = container_of(dev, struct ufsf_feature_info, hpb_dev); > > + hba = container_of(ufsf, struct ufs_hba, ufsf); > > + > > + async_schedule(ufshpb_probe_async, hba); > > + return 0; > > +} > So this is an asynchronous probe that is not visible to the device > driver core? Could the PROBE_PREFER_ASYNCHRONOUS flag have been used > instead to make device probing asynchronous? I added the PROBE_PREFER_ASYNCHRONOUS flag to code and changed it to probe synchronously. > > +static int ufshpb_remove(struct device *dev) > > +{ > > + struct ufshpb_lu *hpb, *n_hpb; > > + struct ufsf_feature_info *ufsf; > > + struct scsi_device *sdev; > > + > > + ufsf = container_of(dev, struct ufsf_feature_info, hpb_dev); > > + > > + dev_set_drvdata(&ufsf->hpb_dev, NULL); > > + > > + list_for_each_entry_safe(hpb, n_hpb, &ufshpb_drv.lh_hpb_lu, > > + list_hpb_lu) { > > + ufshpb_set_state(hpb, HPB_FAILED); > > + > > + sdev = hpb->sdev_ufs_lu; > > + sdev->hostdata = NULL; > > + > > + device_del(&hpb->hpb_lu_dev); > > + > > + dev_info(&hpb->hpb_lu_dev, "hpb_lu_dev refcnt %d\n", > > + kref_read(&hpb->hpb_lu_dev.kobj.kref)); > > + put_device(&hpb->hpb_lu_dev); > > + } > > + dev_info(dev, "ufshpb: remove success\n"); > > + > > + return 0; > > +} > Where is the code that waits for the asynchronously scheduled probe > calls to finish? I changed it to probe without async_schedule. > > diff --git a/drivers/scsi/ufs/ufshpb.h b/drivers/scsi/ufs/ufshpb.h > > new file mode 100644 > > index 000000000000..c6dd88e00849 > > --- /dev/null > > +++ b/drivers/scsi/ufs/ufshpb.h > > @@ -0,0 +1,185 @@ > > +/* SPDX-License-Identifier: GPL-2.0-only */ > > +/* > > + * Universal Flash Storage Host Performance Booster > > + * > > + * Copyright (C) 2017-2018 Samsung Electronics Co., Ltd. > > + * > > + * Authors: > > + * Yongmyung Lee <ymhungry....@samsung.com> > > + * Jinyoung Choi <j-young.c...@samsung.com> > > + * > > + * This program is free software; you can redistribute it and/or > > + * modify it under the terms of the GNU General Public License > > + * as published by the Free Software Foundation; either version 2 > > + * of the License, or (at your option) any later version. > > + * See the COPYING file in the top-level directory or visit > > + * <http://www.gnu.org/licenses/gpl-2.0.html> > > + * > > + * This program is distributed in the hope that it will be useful, > > + * but WITHOUT ANY WARRANTY; without even the implied warranty of > > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the > > + * GNU General Public License for more details. > > + * > > + * This program is provided "AS IS" and "WITH ALL FAULTS" and > > + * without warranty of any kind. You are solely responsible for > > + * determining the appropriateness of using and distributing > > + * the program and assume all risks associated with your exercise > > + * of rights with respect to the program, including but not limited > > + * to infringement of third party rights, the risks and costs of > > + * program errors, damage to or loss of data, programs or equipment, > > + * and unavailability or interruption of operations. Under no > > + * circumstances will the contributor of this Program be liable for > > + * any damages of any kind arising from your use or distribution of > > + * this program. > > + * > > + * The Linux Foundation chooses to take subject only to the GPLv2 > > + * license terms, and distributes only under these terms. > > + */ > Please use an SPDX declaration instead of the full GPLv2 text. OK, I will. Thanks, Daejun.