Commit d2fc401e authored by Xiaofei Tan's avatar Xiaofei Tan Committed by Martin K. Petersen

scsi: hisi_sas: Fix the conflict between dev gone and host reset

There is a possible conflict when a device is removed and host reset occurs
concurrently.

The reason is that then the device is notified as gone, we try to clear the
ITCT, which is notified via an interrupt. The dev gone function pends on
this event with a completion, which is completed when the ITCT interrupt
occurs.

But host reset will disable all interrupts, the wait_for_completion() may
wait indefinitely.

This patch adds an semaphore to synchronise this two processes. The
semaphore is taken by the host reset as the basis of synchronising.
Signed-off-by: default avatarXiaofei Tan <tanxiaofei@huawei.com>
Signed-off-by: default avatarJohn Garry <john.garry@huawei.com>
Signed-off-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
parent 1324ae1c
......@@ -277,6 +277,7 @@ struct hisi_hba {
int n_phy;
spinlock_t lock;
struct semaphore sem;
struct timer_list timer;
struct workqueue_struct *wq;
......
......@@ -914,7 +914,9 @@ static void hisi_sas_dev_gone(struct domain_device *device)
hisi_sas_dereg_device(hisi_hba, device);
down(&hisi_hba->sem);
hisi_hba->hw->clear_itct(hisi_hba, sas_dev);
up(&hisi_hba->sem);
device->lldd_dev = NULL;
}
......@@ -1364,6 +1366,7 @@ static int hisi_sas_controller_reset(struct hisi_hba *hisi_hba)
if (test_and_set_bit(HISI_SAS_RESET_BIT, &hisi_hba->flags))
return -1;
down(&hisi_hba->sem);
dev_info(dev, "controller resetting...\n");
old_state = hisi_hba->hw->get_phys_state(hisi_hba);
......@@ -1378,6 +1381,7 @@ static int hisi_sas_controller_reset(struct hisi_hba *hisi_hba)
if (rc) {
dev_warn(dev, "controller reset failed (%d)\n", rc);
clear_bit(HISI_SAS_REJECT_CMD_BIT, &hisi_hba->flags);
up(&hisi_hba->sem);
scsi_unblock_requests(shost);
goto out;
}
......@@ -1388,6 +1392,7 @@ static int hisi_sas_controller_reset(struct hisi_hba *hisi_hba)
hisi_hba->hw->phys_init(hisi_hba);
msleep(1000);
hisi_sas_refresh_port_id(hisi_hba);
up(&hisi_hba->sem);
if (hisi_hba->reject_stp_links_msk)
hisi_sas_terminate_stp_reject(hisi_hba);
......@@ -2016,6 +2021,7 @@ int hisi_sas_alloc(struct hisi_hba *hisi_hba, struct Scsi_Host *shost)
struct device *dev = hisi_hba->dev;
int i, s, max_command_entries = hisi_hba->hw->max_command_entries;
sema_init(&hisi_hba->sem, 1);
spin_lock_init(&hisi_hba->lock);
for (i = 0; i < hisi_hba->n_phy; i++) {
hisi_sas_phy_init(hisi_hba, i);
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment