scsi: hisi_sas: Check usage count only when the runtime PM status is RPM_SUSPENDING

Users can suspend the machine with 'echo disk > /sys/power/state', but
the suspend will fail because the SAS controller cannot be suspended:

[root@localhost ~]# echo freeze > /sys/power/state
-bash: echo: write error: Device or resource busy
[15104.142955] PM: suspend entry (s2idle)
...
[15104.283465] hisi_sas_v3_hw 0000:32:04.0: entering suspend state
[15104.283480] hisi_sas_v3_hw 0000:30:04.0: entering suspend state
[15104.283500] hisi_sas_v3_hw 0000:32:04.0: PM suspend: host status cannot be suspended
[15104.283508] hisi_sas_v3_hw 0000:30:04.0: PM suspend: host status cannot be suspended
[15104.283516] hisi_sas_v3_hw 0000:32:04.0: PM: pci_pm_suspend(): suspend_v3_hw+0x0/0x210 [hisi_sas_v3_hw] returns -16
[15104.283527] hisi_sas_v3_hw 0000:32:04.0: PM: dpm_run_callback(): pci_pm_suspend+0x0/0x1c0 returns -16
[15104.283524] hisi_sas_v3_hw 0000:30:04.0: PM: pci_pm_suspend(): suspend_v3_hw+0x0/0x210 [hisi_sas_v3_hw] returns -16
[15104.283533] hisi_sas_v3_hw 0000:32:04.0: PM: failed to suspend async: error -16
[15104.283536] hisi_sas_v3_hw 0000:30:04.0: PM: dpm_run_callback(): pci_pm_suspend+0x0/0x1c0 returns -16
[15104.283542] hisi_sas_v3_hw 0000:30:04.0: PM: failed to suspend async: error -16

The problem is that when the ->runtime_suspend() callback
suspend_v3_hw() is executing, the current runtime PM status is
RPM_ACTIVE and the usage count of the controller is not 0, so return
immediately.

To fix it, Check the device usage count only when the runtime PM status
is RPM_SUSPENDING.

Signed-off-by: Yihang Li <liyihang9@huawei.com>
Link: https://lore.kernel.org/r/20241008021822.2617339-7-liyihang9@huawei.com
Reviewed-by: Xiang Chen <chenxiang66@hisilicon.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

diff --git a/drivers/scsi/hisi_sas/hisi_sas_v3_hw.c b/drivers/scsi/hisi_sas/hisi_sas_v3_hw.c
index d48777fc4bd9289a4901c1e94bc5b28a51fac6f3..9e65ad0e6ce0f1e7b97a2f6caf1c97139e6f9e38 100644 (file)
--- a/drivers/scsi/hisi_sas/hisi_sas_v3_hw.c
+++ b/drivers/scsi/hisi_sas/hisi_sas_v3_hw.c
@@ -5048,7 +5048,8 @@ static int _suspend_v3_hw(struct device *device)
        interrupt_disable_v3_hw(hisi_hba);
 
 #ifdef CONFIG_PM
-       if (atomic_read(&device->power.usage_count)) {
+       if ((device->power.runtime_status == RPM_SUSPENDING) &&
+           atomic_read(&device->power.usage_count)) {
                dev_err(dev, "PM suspend: host status cannot be suspended\n");
                rc = -EBUSY;
                goto err_out;