[PATCH V3 7/9] aacraid: Fix AIF triggered IOP_RESET

[Raghava Aditya Renukunta <RaghavaAditya.Renukunta@pmcs.com>]

From: Raghava Aditya Renukunta <raghavaaditya.renukunta@pmcs.com>

while driver removal is in progress or PCI shutdown is invoked, driver
kills AIF aacraid thread, but IOCTL requests from the management tools
re-start AIF thread leading to IOP_RESET.

Fixed by setting adapter_shutdown flag when PCI shutdown is invoked.

Changes in V2:
Set adapter_shutdown flag before shutdown command is sent to \
controller

Changes in V3:
Call aac_send_shut_shutdown first thing in __aac_shutdown
Convert adapter_shutdown to atomic_t variable to prevent \
SMP coherency issues(race conditions)

Signed-off-by: Raghava Aditya Renukunta <raghavaaditya.renukunta@pmcs.com>
---
 drivers/scsi/aacraid/aacraid.h  |  2 +-
 drivers/scsi/aacraid/comminit.c |  6 +++---
 drivers/scsi/aacraid/linit.c    | 15 ++++++++-------
 3 files changed, 12 insertions(+), 11 deletions(-)

diff --git a/drivers/scsi/aacraid/aacraid.h b/drivers/scsi/aacraid/aacraid.h
index 2916288..3473668 100644
--- a/drivers/scsi/aacraid/aacraid.h
+++ b/drivers/scsi/aacraid/aacraid.h
@@ -1234,7 +1234,7 @@ struct aac_dev
 	int			msi_enabled;	/* MSI/MSI-X enabled */
 	struct msix_entry	msixentry[AAC_MAX_MSIX];
 	struct aac_msix_ctx	aac_msix[AAC_MAX_MSIX]; /* context */
-	u8			adapter_shutdown;
+	atomic_t		adapter_shutdown;
 	u32			handle_pci_error;
 };
 
diff --git a/drivers/scsi/aacraid/comminit.c b/drivers/scsi/aacraid/comminit.c
index 0e954e3..d361673 100644
--- a/drivers/scsi/aacraid/comminit.c
+++ b/drivers/scsi/aacraid/comminit.c
@@ -212,8 +212,9 @@ int aac_send_shutdown(struct aac_dev * dev)
 		return -ENOMEM;
 	aac_fib_init(fibctx);
 
-	cmd = (struct aac_close *) fib_data(fibctx);
+	atomic_set(&dev->adapter_shutdown, 1);
 
+	cmd = (struct aac_close *) fib_data(fibctx);
 	cmd->command = cpu_to_le32(VM_CloseAll);
 	cmd->cid = cpu_to_le32(0xfffffffe);
 
@@ -229,7 +230,6 @@ int aac_send_shutdown(struct aac_dev * dev)
 	/* FIB should be freed only after getting the response from the F/W */
 	if (status != -ERESTARTSYS)
 		aac_fib_free(fibctx);
-	dev->adapter_shutdown = 1;
 	if ((dev->pdev->device == PMC_DEVICE_S7 ||
 	     dev->pdev->device == PMC_DEVICE_S8 ||
 	     dev->pdev->device == PMC_DEVICE_S9) &&
@@ -468,7 +468,7 @@ struct aac_dev *aac_init_adapter(struct aac_dev *dev)
 	}
 	dev->max_msix = 0;
 	dev->msi_enabled = 0;
-	dev->adapter_shutdown = 0;
+	atomic_set(&dev->adapter_shutdown, 0);
 	if ((!aac_adapter_sync_cmd(dev, GET_COMM_PREFERRED_SETTINGS,
 	  0, 0, 0, 0, 0, 0,
 	  status+0, status+1, status+2, status+3, status+4))
diff --git a/drivers/scsi/aacraid/linit.c b/drivers/scsi/aacraid/linit.c
index 6944560..27b3fcd 100644
--- a/drivers/scsi/aacraid/linit.c
+++ b/drivers/scsi/aacraid/linit.c
@@ -706,7 +706,7 @@ static long aac_cfg_ioctl(struct file *file,
 	int ret;
 	struct aac_dev *aac;
 	aac = (struct aac_dev *)file->private_data;
-	if (!capable(CAP_SYS_RAWIO) || aac->adapter_shutdown)
+	if (!capable(CAP_SYS_RAWIO) || atomic_read(&aac->adapter_shutdown))
 		return -EPERM;
 	mutex_lock(&aac_mutex);
 	ret = aac_do_ioctl(file->private_data, cmd, (void __user *)arg);
@@ -1078,6 +1078,8 @@ static void __aac_shutdown(struct aac_dev * aac)
 	int i;
 	int cpu;
 
+	aac_send_shutdown(aac);
+
 	if (aac->aif_thread) {
 		int i;
 		/* Clear out events first */
@@ -1089,7 +1091,7 @@ static void __aac_shutdown(struct aac_dev * aac)
 		}
 		kthread_stop(aac->thread);
 	}
-	aac_send_shutdown(aac);
+
 	aac_adapter_disable_int(aac);
 	cpu = cpumask_first(cpu_online_mask);
 	if (aac->pdev->device == PMC_DEVICE_S6 ||
@@ -1474,7 +1476,7 @@ static int aac_resume(struct pci_dev *pdev)
 	* reset this flag to unblock ioctl() as it was set at
 	* aac_send_shutdown() to block ioctls from upperlayer
 	*/
-	aac->adapter_shutdown = 0;
+	atomic_set(&aac->adapter_shutdown, 0);
 	scsi_unblock_requests(shost);
 
 	return 0;
@@ -1553,9 +1555,8 @@ static pci_ers_result_t aac_pci_error_detected(struct pci_dev *pdev,
 	case pci_channel_io_normal:
 		return PCI_ERS_RESULT_CAN_RECOVER;
 	case pci_channel_io_frozen:
-
 		aac->handle_pci_error = 1;
-		aac->adapter_shutdown = 1;
+		atomic_set(&aac->adapter_shutdown, 1);
 
 		scsi_block_requests(aac->scsi_host_ptr);
 		aac_flush_ios(aac);
@@ -1567,7 +1568,7 @@ static pci_ers_result_t aac_pci_error_detected(struct pci_dev *pdev,
 		return PCI_ERS_RESULT_NEED_RESET;
 	case pci_channel_io_perm_failure:
 		aac->handle_pci_error = 1;
-		aac->adapter_shutdown = 1;
+		atomic_set(&aac->adapter_shutdown, 1);
 
 		aac_flush_ios(aac);
 		return PCI_ERS_RESULT_DISCONNECT;
@@ -1636,7 +1637,7 @@ static void aac_pci_resume(struct pci_dev *pdev)
 	 * reset this flag to unblock ioctl() as it was set
 	 * at aac_send_shutdown() to block ioctls from upperlayer
 	 */
-	aac->adapter_shutdown = 0;
+	atomic_set(&aac->adapter_shutdown, 0);
 	aac->handle_pci_error = 0;
 
 	shost_for_each_device(sdev, shost)
-- 
1.9.1