leandrof/linux
1
0
Fork 0
forked from Minki/linux
Code Issues Pull Requests Packages Projects Releases Wiki Activity

[SCSI] storvsc: Implement multi-channel support

Browse Source 
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
This commit is contained in:
K. Y. Srinivasan 2013-06-04 12:05:07 -07:00 committed by James Bottomley
parent c8a2ba3f50
commit 6f94d5de09
1 changed files with 127 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

131
drivers/scsi/storvsc_drv.c
View File

@ -328,6 +328,8 @@ static int storvsc_timeout = 180;
#define STORVSC_MAX_IO_REQUESTS 128
static void storvsc_on_channel_callback(void *context);
/*
* In Hyper-V, each port/path/target maps to 1 scsi host adapter. In
* reality, the path/target is not used (ie always set to 0) so our
@ -364,6 +366,7 @@ struct storvsc_device {
bool destroy;
bool drain_notify;
bool open_sub_channel;
atomic_t num_outstanding_req;
struct Scsi_Host *host;
@ -755,12 +758,104 @@ static unsigned int copy_to_bounce_buffer(struct scatterlist *orig_sgl,
return total_copied;
}
static void handle_sc_creation(struct vmbus_channel *new_sc)
{
struct hv_device *device = new_sc->primary_channel->device_obj;
struct storvsc_device *stor_device;
struct vmstorage_channel_properties props;
stor_device = get_out_stor_device(device);
if (!stor_device)
return;
if (stor_device->open_sub_channel == false)
return;
memset(&props, 0, sizeof(struct vmstorage_channel_properties));
vmbus_open(new_sc,
storvsc_ringbuffer_size,
storvsc_ringbuffer_size,
(void *)&props,
sizeof(struct vmstorage_channel_properties),
storvsc_on_channel_callback, new_sc);
}
static void handle_multichannel_storage(struct hv_device *device, int max_chns)
{
struct storvsc_device *stor_device;
int num_cpus = num_online_cpus();
int num_sc;
struct storvsc_cmd_request *request;
struct vstor_packet *vstor_packet;
int ret, t;
num_sc = ((max_chns > num_cpus) ? num_cpus : max_chns);
stor_device = get_out_stor_device(device);
if (!stor_device)
return;
request = &stor_device->init_request;
vstor_packet = &request->vstor_packet;
stor_device->open_sub_channel = true;
/*
* Establish a handler for dealing with subchannels.
*/
vmbus_set_sc_create_callback(device->channel, handle_sc_creation);
/*
* Check to see if sub-channels have already been created. This
* can happen when this driver is re-loaded after unloading.
*/
if (vmbus_are_subchannels_present(device->channel))
return;
stor_device->open_sub_channel = false;
/*
* Request the host to create sub-channels.
*/
memset(request, 0, sizeof(struct storvsc_cmd_request));
init_completion(&request->wait_event);
vstor_packet->operation = VSTOR_OPERATION_CREATE_SUB_CHANNELS;
vstor_packet->flags = REQUEST_COMPLETION_FLAG;
vstor_packet->sub_channel_count = num_sc;
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)
return;
t = wait_for_completion_timeout(&request->wait_event, 10*HZ);
if (t == 0)
return;
if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO ||
vstor_packet->status != 0)
return;
/*
* Now that we created the sub-channels, invoke the check; this
* may trigger the callback.
*/
stor_device->open_sub_channel = true;
vmbus_are_subchannels_present(device->channel);
}
static int storvsc_channel_init(struct hv_device *device)
{
struct storvsc_device *stor_device;
struct storvsc_cmd_request *request;
struct vstor_packet *vstor_packet;
int ret, t;
int max_chns;
bool process_sub_channels = false;
stor_device = get_out_stor_device(device);
if (!stor_device)
@ -855,6 +950,19 @@ static int storvsc_channel_init(struct hv_device *device)
vstor_packet->status != 0)
goto cleanup;
/*
* Check to see if multi-channel support is there.
* Hosts that implement protocol version of 5.1 and above
* support multi-channel.
*/
max_chns = vstor_packet->storage_channel_properties.max_channel_cnt;
if ((vmbus_proto_version != VERSION_WIN7) &&
(vmbus_proto_version != VERSION_WS2008)) {
if (vstor_packet->storage_channel_properties.flags &
STORAGE_CHANNEL_SUPPORTS_MULTI_CHANNEL)
process_sub_channels = true;
}
memset(vstor_packet, 0, sizeof(struct vstor_packet));
vstor_packet->operation = VSTOR_OPERATION_END_INITIALIZATION;
vstor_packet->flags = REQUEST_COMPLETION_FLAG;
@ -879,6 +987,9 @@ static int storvsc_channel_init(struct hv_device *device)
vstor_packet->status != 0)
goto cleanup;
if (process_sub_channels)
handle_multichannel_storage(device, max_chns);
cleanup:
return ret;
@ -1100,7 +1211,8 @@ static void storvsc_on_receive(struct hv_device *device,
static void storvsc_on_channel_callback(void *context)
{
struct hv_device *device = (struct hv_device *)context;
struct vmbus_channel *channel = (struct vmbus_channel *)context;
struct hv_device *device;
struct storvsc_device *stor_device;
u32 bytes_recvd;
u64 request_id;
@ -1108,13 +1220,17 @@ static void storvsc_on_channel_callback(void *context)
struct storvsc_cmd_request *request;
int ret;
if (channel->primary_channel != NULL)
device = channel->primary_channel->device_obj;
else
device = channel->device_obj;
stor_device = get_in_stor_device(device);
if (!stor_device)
return;
do {
ret = vmbus_recvpacket(device->channel, packet,
ret = vmbus_recvpacket(channel, packet,
ALIGN((sizeof(struct vstor_packet) -
vmscsi_size_delta), 8),
&bytes_recvd, &request_id);
@ -1155,7 +1271,7 @@ static int storvsc_connect_to_vsp(struct hv_device *device, u32 ring_size)
ring_size,
(void *)&props,
sizeof(struct vmstorage_channel_properties),
storvsc_on_channel_callback, device);
storvsc_on_channel_callback, device->channel);
if (ret != 0)
return ret;
@ -1207,6 +1323,7 @@ static int storvsc_do_io(struct hv_device *device,
{
struct storvsc_device *stor_device;
struct vstor_packet *vstor_packet;
struct vmbus_channel *outgoing_channel;
int ret = 0;
vstor_packet = &request->vstor_packet;
@ -1217,6 +1334,11 @@ static int storvsc_do_io(struct hv_device *device,
request->device = device;
/*
* Select an an appropriate channel to send the request out.
*/
outgoing_channel = vmbus_get_outgoing_channel(device->channel);
vstor_packet->flags |= REQUEST_COMPLETION_FLAG;
@ -1234,7 +1356,7 @@ static int storvsc_do_io(struct hv_device *device,
vstor_packet->operation = VSTOR_OPERATION_EXECUTE_SRB;
if (request->data_buffer.len) {
ret = vmbus_sendpacket_multipagebuffer(device->channel,
ret = vmbus_sendpacket_multipagebuffer(outgoing_channel,
&request->data_buffer,
vstor_packet,
(sizeof(struct vstor_packet) -
@ -1643,6 +1765,7 @@ static int storvsc_probe(struct hv_device *device,
}
stor_device->destroy = false;
stor_device->open_sub_channel = false;
init_waitqueue_head(&stor_device->waiting_to_drain);
stor_device->device = device;
stor_device->host = host;