[PATCH 3/4] scsi: storvsc: Refactor the code in storvsc_channel_init()

From: K. Y. Srinivasan
Date: Thu Dec 10 2015 - 17:41:24 EST


The function storvsc_channel_init() repeatedly interacts with the host to
extract various channel properties. Refactor this code to eliminate code
repetition.

Signed-off-by: K. Y. Srinivasan <kys@xxxxxxxxxxxxx>
Reviewed-by: Long Li <longli@xxxxxxxxxxxxx>
Tested-by: Alex Ng <alexng@xxxxxxxxxxxxx>
---
drivers/scsi/storvsc_drv.c | 155 ++++++++++++++++----------------------------
1 files changed, 57 insertions(+), 98 deletions(-)

diff --git a/drivers/scsi/storvsc_drv.c b/drivers/scsi/storvsc_drv.c
index b94d471..6f18e94 100644
--- a/drivers/scsi/storvsc_drv.c
+++ b/drivers/scsi/storvsc_drv.c
@@ -721,29 +721,16 @@ static void cache_wwn(struct storvsc_device *stor_device,
}
}

-static int storvsc_channel_init(struct hv_device *device, bool is_fc)
+static int storvsc_execute_vstor_op(struct hv_device *device,
+ struct storvsc_cmd_request *request,
+ bool status_check)
{
- struct storvsc_device *stor_device;
- struct storvsc_cmd_request *request;
struct vstor_packet *vstor_packet;
- int ret, t, i;
- int max_chns;
- bool process_sub_channels = false;
-
- stor_device = get_out_stor_device(device);
- if (!stor_device)
- return -ENODEV;
+ int ret, t;

- request = &stor_device->init_request;
vstor_packet = &request->vstor_packet;

- /*
- * Now, initiate the vsc/vsp initialization protocol on the open
- * channel
- */
- memset(request, 0, sizeof(struct storvsc_cmd_request));
init_completion(&request->wait_event);
- vstor_packet->operation = VSTOR_OPERATION_BEGIN_INITIALIZATION;
vstor_packet->flags = REQUEST_COMPLETION_FLAG;

ret = vmbus_sendpacket(device->channel, vstor_packet,
@@ -753,27 +740,62 @@ static int storvsc_channel_init(struct hv_device *device, bool is_fc)
VM_PKT_DATA_INBAND,
VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
if (ret != 0)
- goto cleanup;
+ goto done;

t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
if (t == 0) {
ret = -ETIMEDOUT;
- goto cleanup;
+ goto done;
}

+ if (!status_check)
+ goto done;
+
if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO ||
vstor_packet->status != 0) {
ret = -EINVAL;
- goto cleanup;
+ goto done;
}

+done:
+ return ret;
+}
+
+static int storvsc_channel_init(struct hv_device *device, bool is_fc)
+{
+ struct storvsc_device *stor_device;
+ struct storvsc_cmd_request *request;
+ struct vstor_packet *vstor_packet;
+ int ret, i;
+ int max_chns;
+ bool process_sub_channels = false;
+
+ stor_device = get_out_stor_device(device);
+ if (!stor_device)
+ return -ENODEV;
+
+ request = &stor_device->init_request;
+ vstor_packet = &request->vstor_packet;
+
+ /*
+ * Now, initiate the vsc/vsp initialization protocol on the open
+ * channel
+ */
+ memset(request, 0, sizeof(struct storvsc_cmd_request));
+ vstor_packet->operation = VSTOR_OPERATION_BEGIN_INITIALIZATION;
+ ret = storvsc_execute_vstor_op(device, request, true);
+ if (ret)
+ goto cleanup;
+
+ /*
+ * Query host supported protocol version.
+ */

for (i = 0; i < ARRAY_SIZE(vmstor_protocols); i++) {
/* reuse the packet for version range supported */
memset(vstor_packet, 0, sizeof(struct vstor_packet));
vstor_packet->operation =
VSTOR_OPERATION_QUERY_PROTOCOL_VERSION;
- vstor_packet->flags = REQUEST_COMPLETION_FLAG;

vstor_packet->version.major_minor =
vmstor_protocols[i].protocol_version;
@@ -783,20 +805,9 @@ static int storvsc_channel_init(struct hv_device *device, bool is_fc)
*/
vstor_packet->version.revision = 0;

- ret = vmbus_sendpacket(device->channel, vstor_packet,
- (sizeof(struct vstor_packet) -
- vmscsi_size_delta),
- (unsigned long)request,
- VM_PKT_DATA_INBAND,
- VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
- if (ret != 0)
- goto cleanup;
-
- t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
- if (t == 0) {
- ret = -ETIMEDOUT;
+ ret = storvsc_execute_vstor_op(device, request, false);
+ if (ret)
goto cleanup;
- }

if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO) {
ret = -EINVAL;
@@ -822,32 +833,14 @@ static int storvsc_channel_init(struct hv_device *device, bool is_fc)
goto cleanup;
}

-
+ /*
+ * Query channel properties.
+ */
memset(vstor_packet, 0, sizeof(struct vstor_packet));
vstor_packet->operation = VSTOR_OPERATION_QUERY_PROPERTIES;
- vstor_packet->flags = REQUEST_COMPLETION_FLAG;
-
- ret = vmbus_sendpacket(device->channel, vstor_packet,
- (sizeof(struct vstor_packet) -
- vmscsi_size_delta),
- (unsigned long)request,
- VM_PKT_DATA_INBAND,
- VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
-
- if (ret != 0)
- goto cleanup;
-
- t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
- if (t == 0) {
- ret = -ETIMEDOUT;
- goto cleanup;
- }
-
- if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO ||
- vstor_packet->status != 0) {
- ret = -EINVAL;
+ ret = storvsc_execute_vstor_op(device, request, true);
+ if (ret)
goto cleanup;
- }

/*
* Check to see if multi-channel support is there.
@@ -866,30 +859,15 @@ static int storvsc_channel_init(struct hv_device *device, bool is_fc)
if (!is_fc)
goto done;

+ /*
+ * For FC devices retrieve FC HBA data.
+ */
memset(vstor_packet, 0, sizeof(struct vstor_packet));
vstor_packet->operation = VSTOR_OPERATION_FCHBA_DATA;
- vstor_packet->flags = REQUEST_COMPLETION_FLAG;

- ret = vmbus_sendpacket(device->channel, vstor_packet,
- (sizeof(struct vstor_packet) -
- vmscsi_size_delta),
- (unsigned long)request,
- VM_PKT_DATA_INBAND,
- VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
-
- if (ret != 0)
- goto cleanup;
-
- t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
- if (t == 0) {
- ret = -ETIMEDOUT;
- goto cleanup;
- }
-
- if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO ||
- vstor_packet->status != 0)
+ ret = storvsc_execute_vstor_op(device, request, true);
+ if (ret)
goto cleanup;
-
/*
* Cache the currently active port and node ww names.
*/
@@ -899,29 +877,10 @@ done:

memset(vstor_packet, 0, sizeof(struct vstor_packet));
vstor_packet->operation = VSTOR_OPERATION_END_INITIALIZATION;
- vstor_packet->flags = REQUEST_COMPLETION_FLAG;

- ret = vmbus_sendpacket(device->channel, vstor_packet,
- (sizeof(struct vstor_packet) -
- vmscsi_size_delta),
- (unsigned long)request,
- VM_PKT_DATA_INBAND,
- VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
-
- if (ret != 0)
- goto cleanup;
-
- t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
- if (t == 0) {
- ret = -ETIMEDOUT;
- goto cleanup;
- }
-
- if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO ||
- vstor_packet->status != 0) {
- ret = -EINVAL;
+ ret = storvsc_execute_vstor_op(device, request, true);
+ if (ret)
goto cleanup;
- }

if (process_sub_channels)
handle_multichannel_storage(device, max_chns);
--
1.7.4.1

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