Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751704Ab3FDSaO (ORCPT ); Tue, 4 Jun 2013 14:30:14 -0400 Received: from p3plsmtps2ded02.prod.phx3.secureserver.net ([208.109.80.59]:60198 "EHLO p3plsmtps2ded02.prod.phx3.secureserver.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751207Ab3FDSaD (ORCPT ); Tue, 4 Jun 2013 14:30:03 -0400 x-originating-ip: 72.167.245.219 From: "K. Y. Srinivasan" To: gregkh@linuxfoundation.org, linux-kernel@vger.kernel.org, devel@linuxdriverproject.org, ohering@suse.com, jbottomley@parallels.com, hch@infradead.org, linux-scsi@vger.kernel.org Cc: "K. Y. Srinivasan" Subject: [PATCH 3/5] Drivers: scsi: storvsc: Implement multi-channel support Date: Tue, 4 Jun 2013 12:05:07 -0700 Message-Id: <1370372709-10098-3-git-send-email-kys@microsoft.com> X-Mailer: git-send-email 1.7.4.1 In-Reply-To: <1370372709-10098-1-git-send-email-kys@microsoft.com> References: <1370372674-10046-1-git-send-email-kys@microsoft.com> <1370372709-10098-1-git-send-email-kys@microsoft.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 7597 Lines: 247 Implement multi-channel support for the storage devices. Signed-off-by: K. Y. Srinivasan Reviewed-by: Haiyang Zhang --- drivers/scsi/storvsc_drv.c | 131 ++++++++++++++++++++++++++++++++++++++++++- 1 files changed, 127 insertions(+), 4 deletions(-) diff --git a/drivers/scsi/storvsc_drv.c b/drivers/scsi/storvsc_drv.c index 9451989..1d4d425 100644 --- a/drivers/scsi/storvsc_drv.c +++ b/drivers/scsi/storvsc_drv.c @@ -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; -- 1.7.4.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/