[v2] scsi: storvsc: Add the support of hibernation

Commit Message

Dexuan Cui Sept. 25, 2019, 8:11 p.m. UTC

When we're in storvsc_suspend(), we're sure the SCSI layer has quiesced the
scsi device by scsi_bus_suspend() -> ... -> scsi_device_quiesce(), so the
low level SCSI adapter driver only needs to suspend/resume its own state.

Signed-off-by: Dexuan Cui <[e-mail]>
Acked-by: Martin K. Petersen <[e-mail]>

---

This patch is basically a pure Hyper-V specific change and it has a
build dependency on the commit 271b2224d42f ("Drivers: hv: vmbus: Implement
suspend/resume for VSC drivers for hibernation"), which is on Sasha Levin's
Hyper-V tree's hyperv-next branch:
https://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux.git/log/?h=hyperv-next

I request this patch should go through Sasha's tree rather than the
SCSI tree.

In v2:
	Added Acked-by from Martin.

	@Sasha: I think the patch can go through the hyper-v tree, since
                we have the Ack from Martin. :-)

	No other change.


 drivers/scsi/storvsc_drv.c | 41 +++++++++++++++++++++++++++++++++++++++++
 1 file changed, 41 insertions(+)

Comments

Dexuan Cui Sept. 25, 2019, 10:15 p.m. UTC | #1

> From: kbuild test robot <[e-mail]>
> Sent: Wednesday, September 25, 2019 2:55 PM
> To: Dexuan Cui <[e-mail]>
> Cc: [e-mail]; KY Srinivasan <[e-mail]>; Haiyang Zhang
> <[e-mail]>; Stephen Hemminger
> <[e-mail]>; [e-mail]; [e-mail];
> [e-mail]; [e-mail];
> [e-mail]; [e-mail]; Michael Kelley
> <[e-mail]>; Dexuan Cui <[e-mail]>
> Subject: Re: [PATCH v2] scsi: storvsc: Add the support of hibernation
> 
> Hi Dexuan,
> 
> Thank you for the patch! Yet something to improve:
> 
> [auto build test ERROR on mkp-scsi/for-next]
> [cannot apply to v5.3 next-20190924]
> [if your patch is applied to the wrong git tree, please drop us a note to help
> improve the system. BTW, we also suggest to use '--base' option to specify the
> base tree in git format-patch, please see
> [...snipped...]
> config: x86_64-rhel (attached as .config)
> compiler: gcc-7 (Debian 7.4.0-13) 7.4.0
> reproduce:
>         # save the attached .config to linux build tree
>         make ARCH=x86_64
> 
> If you fix the issue, kindly add following tag
> Reported-by: kbuild test robot <[e-mail]>
> 
> All errors (new ones prefixed by >>):
> 
> >> drivers//scsi/storvsc_drv.c:1981:3: error: 'struct hv_driver' has no member
> named 'suspend'
>      .suspend = storvsc_suspend,
>       ^~~~~~~

This patch depends on the below patch in Linus's tree (today):
271b2224d42f ("Drivers: hv: vmbus: Implement suspend/resume for VSC drivers for hibernation")
So, we don't really have an issue here.

The mkp-scsi/for-next branch needs to do a merge with Linus's master branch.

Thanks,
-- Dexuan

Sasha Levin Oct. 1, 2019, 6:51 p.m. UTC | #2

On Wed, Sep 25, 2019 at 08:11:08PM +0000, Dexuan Cui wrote:
>When we're in storvsc_suspend(), we're sure the SCSI layer has quiesced the
>scsi device by scsi_bus_suspend() -> ... -> scsi_device_quiesce(), so the
>low level SCSI adapter driver only needs to suspend/resume its own state.
>
>Signed-off-by: Dexuan Cui <[e-mail]>
>Acked-by: Martin K. Petersen <[e-mail]>
>
>---
>
>This patch is basically a pure Hyper-V specific change and it has a
>build dependency on the commit 271b2224d42f ("Drivers: hv: vmbus: Implement
>suspend/resume for VSC drivers for hibernation"), which is on Sasha Levin's
>Hyper-V tree's hyperv-next branch:
>https://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux.git/log/?h=hyperv-next
>
>I request this patch should go through Sasha's tree rather than the
>SCSI tree.
>
>In v2:
>	Added Acked-by from Martin.
>
>	@Sasha: I think the patch can go through the hyper-v tree, since
>                we have the Ack from Martin. :-)

Queued up for hyperv-next, thanks!

--
Thanks,
Sasha

Patch

diff --git a/drivers/scsi/storvsc_drv.c b/drivers/scsi/storvsc_drv.c
index ed8b9ac..9fbf604 100644
--- a/drivers/scsi/storvsc_drv.c
+++ b/drivers/scsi/storvsc_drv.c
@@ -1727,6 +1727,13 @@  enum {
 
 MODULE_DEVICE_TABLE(vmbus, id_table);
 
+static const struct { guid_t guid; } fc_guid = { HV_SYNTHFC_GUID };
+
+static bool hv_dev_is_fc(struct hv_device *hv_dev)
+{
+	return guid_equal(&fc_guid.guid, &hv_dev->dev_type);
+}
+
 static int storvsc_probe(struct hv_device *device,
 			const struct hv_vmbus_device_id *dev_id)
 {
@@ -1935,11 +1942,45 @@  static int storvsc_remove(struct hv_device *dev)
 	return 0;
 }
 
+static int storvsc_suspend(struct hv_device *hv_dev)
+{
+	struct storvsc_device *stor_device = hv_get_drvdata(hv_dev);
+	struct Scsi_Host *host = stor_device->host;
+	struct hv_host_device *host_dev = shost_priv(host);
+
+	storvsc_wait_to_drain(stor_device);
+
+	drain_workqueue(host_dev->handle_error_wq);
+
+	vmbus_close(hv_dev->channel);
+
+	memset(stor_device->stor_chns, 0,
+	       num_possible_cpus() * sizeof(void *));
+
+	kfree(stor_device->stor_chns);
+	stor_device->stor_chns = NULL;
+
+	cpumask_clear(&stor_device->alloced_cpus);
+
+	return 0;
+}
+
+static int storvsc_resume(struct hv_device *hv_dev)
+{
+	int ret;
+
+	ret = storvsc_connect_to_vsp(hv_dev, storvsc_ringbuffer_size,
+				     hv_dev_is_fc(hv_dev));
+	return ret;
+}
+
 static struct hv_driver storvsc_drv = {
 	.name = KBUILD_MODNAME,
 	.id_table = id_table,
 	.probe = storvsc_probe,
 	.remove = storvsc_remove,
+	.suspend = storvsc_suspend,
+	.resume = storvsc_resume,
 	.driver = {
 		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
 	},