From 7c48bfd038e570cd12b33d6ab13316f3a0b0d1a7 Mon Sep 17 00:00:00 2001 From: Akinobu Mita Date: Thu, 23 Oct 2014 13:25:12 +0300 Subject: [PATCH] ufs: fix reference counting of W-LUs UFS driver adds three well known LUs in the initialization, but those reference counts are not decremented, so it makes ufshcd module impossible to unload. This fixes it by putting scsi_device_put() in the initalization, and in order to protect concurrent access to hba->sdev_ufs_device (UFS Device W-LU) from manual delete, increment the reference count while requesting device power mode setting. The rest of W-LUs (hba->sdev_boot and hba->sdev_rpmb) are not directly used from driver, so these references in struct ufs_hba are removed. Signed-off-by: Akinobu Mita Reviewed-by: Maya Erez Reviewed-by: Dolev Raviv Signed-off-by: Christoph Hellwig --- drivers/scsi/ufs/ufshcd.c | 74 +++++++++++++++++++-------------------- drivers/scsi/ufs/ufshcd.h | 2 -- 2 files changed, 36 insertions(+), 40 deletions(-) diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c index 497c38a4a866..59b654467d48 100644 --- a/drivers/scsi/ufs/ufshcd.c +++ b/drivers/scsi/ufs/ufshcd.c @@ -2844,8 +2844,13 @@ static void ufshcd_slave_destroy(struct scsi_device *sdev) hba = shost_priv(sdev->host); scsi_deactivate_tcq(sdev, hba->nutrs); /* Drop the reference as it won't be needed anymore */ - if (ufshcd_scsi_to_upiu_lun(sdev->lun) == UFS_UPIU_UFS_DEVICE_WLUN) + if (ufshcd_scsi_to_upiu_lun(sdev->lun) == UFS_UPIU_UFS_DEVICE_WLUN) { + unsigned long flags; + + spin_lock_irqsave(hba->host->host_lock, flags); hba->sdev_ufs_device = NULL; + spin_unlock_irqrestore(hba->host->host_lock, flags); + } } /** @@ -4062,6 +4067,8 @@ static void ufshcd_init_icc_levels(struct ufs_hba *hba) static int ufshcd_scsi_add_wlus(struct ufs_hba *hba) { int ret = 0; + struct scsi_device *sdev_rpmb; + struct scsi_device *sdev_boot; hba->sdev_ufs_device = __scsi_add_device(hba->host, 0, 0, ufshcd_upiu_wlun_to_scsi_wlun(UFS_UPIU_UFS_DEVICE_WLUN), NULL); @@ -4070,56 +4077,33 @@ static int ufshcd_scsi_add_wlus(struct ufs_hba *hba) hba->sdev_ufs_device = NULL; goto out; } + scsi_device_put(hba->sdev_ufs_device); - hba->sdev_boot = __scsi_add_device(hba->host, 0, 0, + sdev_boot = __scsi_add_device(hba->host, 0, 0, ufshcd_upiu_wlun_to_scsi_wlun(UFS_UPIU_BOOT_WLUN), NULL); - if (IS_ERR(hba->sdev_boot)) { - ret = PTR_ERR(hba->sdev_boot); - hba->sdev_boot = NULL; + if (IS_ERR(sdev_boot)) { + ret = PTR_ERR(sdev_boot); goto remove_sdev_ufs_device; } + scsi_device_put(sdev_boot); - hba->sdev_rpmb = __scsi_add_device(hba->host, 0, 0, + sdev_rpmb = __scsi_add_device(hba->host, 0, 0, ufshcd_upiu_wlun_to_scsi_wlun(UFS_UPIU_RPMB_WLUN), NULL); - if (IS_ERR(hba->sdev_rpmb)) { - ret = PTR_ERR(hba->sdev_rpmb); - hba->sdev_rpmb = NULL; + if (IS_ERR(sdev_rpmb)) { + ret = PTR_ERR(sdev_rpmb); goto remove_sdev_boot; } + scsi_device_put(sdev_rpmb); goto out; remove_sdev_boot: - scsi_remove_device(hba->sdev_boot); + scsi_remove_device(sdev_boot); remove_sdev_ufs_device: scsi_remove_device(hba->sdev_ufs_device); out: return ret; } -/** - * ufshcd_scsi_remove_wlus - Removes the W-LUs which were added by - * ufshcd_scsi_add_wlus() - * @hba: per-adapter instance - * - */ -static void ufshcd_scsi_remove_wlus(struct ufs_hba *hba) -{ - if (hba->sdev_ufs_device) { - scsi_remove_device(hba->sdev_ufs_device); - hba->sdev_ufs_device = NULL; - } - - if (hba->sdev_boot) { - scsi_remove_device(hba->sdev_boot); - hba->sdev_boot = NULL; - } - - if (hba->sdev_rpmb) { - scsi_remove_device(hba->sdev_rpmb); - hba->sdev_rpmb = NULL; - } -} - /** * ufshcd_probe_hba - probe hba to detect device and initialize * @hba: per-adapter instance @@ -4675,11 +4659,25 @@ static int ufshcd_set_dev_pwr_mode(struct ufs_hba *hba, { unsigned char cmd[6] = { START_STOP }; struct scsi_sense_hdr sshdr; - struct scsi_device *sdp = hba->sdev_ufs_device; + struct scsi_device *sdp; + unsigned long flags; int ret; - if (!sdp || !scsi_device_online(sdp)) - return -ENODEV; + spin_lock_irqsave(hba->host->host_lock, flags); + sdp = hba->sdev_ufs_device; + if (sdp) { + ret = scsi_device_get(sdp); + if (!ret && !scsi_device_online(sdp)) { + ret = -ENODEV; + scsi_device_put(sdp); + } + } else { + ret = -ENODEV; + } + spin_unlock_irqrestore(hba->host->host_lock, flags); + + if (ret) + return ret; /* * If scsi commands fail, the scsi mid-layer schedules scsi error- @@ -4718,6 +4716,7 @@ static int ufshcd_set_dev_pwr_mode(struct ufs_hba *hba, if (!ret) hba->curr_dev_pwr_mode = pwr_mode; out: + scsi_device_put(sdp); hba->host->eh_noresume = 0; return ret; } @@ -5231,7 +5230,6 @@ EXPORT_SYMBOL(ufshcd_shutdown); void ufshcd_remove(struct ufs_hba *hba) { scsi_remove_host(hba->host); - ufshcd_scsi_remove_wlus(hba); /* disable interrupts */ ufshcd_disable_intr(hba, hba->intr_mask); ufshcd_hba_stop(hba); diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h index 58ecdff5065c..4a574aa45855 100644 --- a/drivers/scsi/ufs/ufshcd.h +++ b/drivers/scsi/ufs/ufshcd.h @@ -392,8 +392,6 @@ struct ufs_hba { * "UFS device" W-LU. */ struct scsi_device *sdev_ufs_device; - struct scsi_device *sdev_rpmb; - struct scsi_device *sdev_boot; enum ufs_dev_pwr_mode curr_dev_pwr_mode; enum uic_link_state uic_link_state;