[PATCH V2 3/4] scsi: storvsc: Refactor the code in storvsc_channel_init()

From: K. Y. Srinivasan
Date: Sat Dec 12 2015 - 15:20:49 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>
Reviewed-by: Johannes Thumshirn <jthumshirn@xxxxxxx>
Tested-by: Alex Ng <alexng@xxxxxxxxxxxxx>
---
V2: Fixed error paths - Dan Carpenter <dan.carpenter@xxxxxxxxxx>

drivers/scsi/storvsc_drv.c | 126 ++++++++++++++++----------------------------
1 files changed, 46 insertions(+), 80 deletions(-)

diff --git a/drivers/scsi/storvsc_drv.c b/drivers/scsi/storvsc_drv.c
index ab9828c..947f812 100644
--- a/drivers/scsi/storvsc_drv.c
+++ b/drivers/scsi/storvsc_drv.c
@@ -721,29 +721,17 @@ 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,
@@ -759,17 +747,50 @@ static int storvsc_channel_init(struct hv_device *device, bool is_fc)
if (t == 0)
return -ETIMEDOUT;

+ if (!status_check)
+ return ret;
+
if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO ||
vstor_packet->status != 0)
return -EINVAL;

+ 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)
+ return ret;
+ /*
+ * 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;
@@ -778,20 +799,10 @@ static int storvsc_channel_init(struct hv_device *device, bool is_fc)
* The revision number is only used in Windows; set it to 0.
*/
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);
+ ret = storvsc_execute_vstor_op(device, request, false);
if (ret != 0)
return ret;

- t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
- if (t == 0)
- return -ETIMEDOUT;
-
if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO)
return -EINVAL;

@@ -815,26 +826,10 @@ static int storvsc_channel_init(struct hv_device *device, bool is_fc)

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);
-
+ ret = storvsc_execute_vstor_op(device, request, true);
if (ret != 0)
return ret;

- t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
- if (t == 0)
- return -ETIMEDOUT;
-
- if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO ||
- vstor_packet->status != 0)
- return -EINVAL;
-
/*
* Check to see if multi-channel support is there.
* Hosts that implement protocol version of 5.1 and above
@@ -852,28 +847,15 @@ 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);
-
+ ret = storvsc_execute_vstor_op(device, request, true);
if (ret != 0)
return ret;

- t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
- if (t == 0)
- return -ETIMEDOUT;
-
- if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO ||
- vstor_packet->status != 0)
- return -EINVAL;
-
/*
* Cache the currently active port and node ww names.
*/
@@ -883,26 +865,10 @@ 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);
-
+ ret = storvsc_execute_vstor_op(device, request, true);
if (ret != 0)
return ret;

- t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
- if (t == 0)
- return -ETIMEDOUT;
-
- if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO ||
- vstor_packet->status != 0)
- return -EINVAL;
-
if (process_sub_channels)
handle_multichannel_storage(device, max_chns);

--
1.7.4.1

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/