From: Alexander Graf <agraf@suse•de>
To: Gavin Shan <gwshan@linux•vnet.ibm.com>
Cc: aik@ozlabs•ru, kvm-ppc@vger•kernel.org,
Alex Williamson <alex.williamson@redhat•com>,
qiudayu@linux•vnet.ibm.com, linuxppc-dev@lists•ozlabs.org
Subject: Re: [PATCH v7 3/3] drivers/vfio: EEH support for VFIO PCI device
Date: Wed, 28 May 2014 15:12:35 +0200 [thread overview]
Message-ID: <5385E0C3.8020000@suse.de> (raw)
In-Reply-To: <20140528124947.GA19346@shangw>
On 28.05.14 14:49, Gavin Shan wrote:
> On Wed, May 28, 2014 at 01:41:35PM +0200, Alexander Graf wrote:
>> On 28.05.14 02:55, Gavin Shan wrote:
>>> On Tue, May 27, 2014 at 12:15:27PM -0600, Alex Williamson wrote:
>>>> On Tue, 2014-05-27 at 18:40 +1000, Gavin Shan wrote:
>>>>> The patch adds new IOCTL commands for sPAPR VFIO container device
>>>>> to support EEH functionality for PCI devices, which have been passed
>>>>> through from host to somebody else via VFIO.
>>>>>
>>>>> Signed-off-by: Gavin Shan <gwshan@linux•vnet.ibm.com>
>>>>> ---
>>>>> Documentation/vfio.txt | 92 ++++++++++++++++++++++++++++++++++++-
>>>>> drivers/vfio/pci/Makefile | 1 +
>>>>> drivers/vfio/pci/vfio_pci.c | 20 +++++---
>>>>> drivers/vfio/pci/vfio_pci_eeh.c | 46 +++++++++++++++++++
>>>>> drivers/vfio/pci/vfio_pci_private.h | 5 ++
>>>>> drivers/vfio/vfio_iommu_spapr_tce.c | 85 ++++++++++++++++++++++++++++++++++
>>>>> include/uapi/linux/vfio.h | 66 ++++++++++++++++++++++++++
>>>>> 7 files changed, 308 insertions(+), 7 deletions(-)
>>>>> create mode 100644 drivers/vfio/pci/vfio_pci_eeh.c
>> [...]
>>
>>>>> diff --git a/include/uapi/linux/vfio.h b/include/uapi/linux/vfio.h
>>>>> index cb9023d..c5fac36 100644
>>>>> --- a/include/uapi/linux/vfio.h
>>>>> +++ b/include/uapi/linux/vfio.h
>>>>> @@ -455,6 +455,72 @@ struct vfio_iommu_spapr_tce_info {
>>>>> #define VFIO_IOMMU_SPAPR_TCE_GET_INFO _IO(VFIO_TYPE, VFIO_BASE + 12)
>>>>> +/*
>>>>> + * EEH functionality can be enabled or disabled on one specific device.
>>>>> + * Also, the DMA or IO frozen state can be removed from the frozen PE
>>>>> + * if required.
>>>>> + */
>>>>> +struct vfio_eeh_pe_set_option {
>>>>> + __u32 argsz;
>>>>> + __u32 flags;
>>>>> + __u32 option;
>>>>> +#define VFIO_EEH_PE_SET_OPT_DISABLE 0 /* Disable EEH */
>>>>> +#define VFIO_EEH_PE_SET_OPT_ENABLE 1 /* Enable EEH */
>>>>> +#define VFIO_EEH_PE_SET_OPT_IO 2 /* Enable IO */
>>>>> +#define VFIO_EEH_PE_SET_OPT_DMA 3 /* Enable DMA */
>>>> This is more of a "command" than an "option" isn't it? Each of these
>>>> probably needs a more significant description.
>>>>
>>> Yeah, it would be regarded as "opcode" and I'll add more description about
>>> them in next revision.
>> Please just call them commands.
>>
> Ok. I guess you want me to change the macro names like this ?
>
> #define VFIO_EEH_CMD_DISABLE 0 /* Disable EEH functionality */
> #define VFIO_EEH_CMD_ENABLE 1 /* Enable EEH functionality */
> #define VFIO_EEH_CMD_ENABLE_IO 2 /* Enable IO for frozen PE */
> #define VFIO_EEH_CMD_ENABLE_DMA 3 /* Enable DMA for frozen PE */
Yes, the ioctl name too.
>
>>>>> +};
>>>>> +
>>>>> +#define VFIO_EEH_PE_SET_OPTION _IO(VFIO_TYPE, VFIO_BASE + 21)
>>>>> +
>>>>> +/*
>>>>> + * Each EEH PE should have unique address to be identified. PE's
>>>>> + * sharing mode is also useful information as well.
>>>>> + */
>>>>> +#define VFIO_EEH_PE_GET_ADDRESS 0 /* Get address */
>>>>> +#define VFIO_EEH_PE_GET_MODE 1 /* Query mode */
>>>>> +#define VFIO_EEH_PE_MODE_NONE 0 /* Not a PE */
>>>>> +#define VFIO_EEH_PE_MODE_NOT_SHARED 1 /* Exclusive */
>>>>> +#define VFIO_EEH_PE_MODE_SHARED 2 /* Shared mode */
>>>>> +
>>>>> +/*
>>>>> + * EEH PE might have been frozen because of PCI errors. Also, it might
>>>>> + * be experiencing reset for error revoery. The following command helps
>>>>> + * to get the state.
>>>>> + */
>>>>> +struct vfio_eeh_pe_get_state {
>>>>> + __u32 argsz;
>>>>> + __u32 flags;
>>>>> + __u32 state;
>>>>> +};
>>>> Should state be a union to better describe the value returned? What
>>>> exactly is the address and why does the user need to know it? Does this
>>>> need user input or could we just return the address and mode regardless?
>>>>
>>> Ok. I think you want enum (not union) for state. I'll have macros for the
>>> state in next revision as I did that for other cases.
>>>
>>> Those macros defined for "address" just for ABI stuff as Alex.G mentioned.
>>> There isn't corresponding ioctl command for host to get address any more
>>> because QEMU (user) will have to figure it out by himself. The "address"
>>> here means PE address and user has to figure it out according to PE
>>> segmentation.
>> Why would the user ever need the address?
>>
> I will remove those "address" related macros in next revision because it's
> user-level bussiness, not related to host kernel any more.
Ok, so the next question is whether there will be any state outside of
GET_MODE left in the future.
Alex
> If the user is QEMU + guest, we need the address to identify the PE though PHB
> BUID could be used as same purpose to get PHB, which is one-to-one mapping with
> IOMMU group on sPAPR platform. However, once the PE address is built and returned
> to guest, guest will use the PE address as input parameter in subsequent RTAS
> calls.
>
> If the user is some kind of application who just uses the ioctl() without supporting
> RTAS calls. We don't need care about PE address.
>
> Thanks,
> Gavin
>
> --
> To unsubscribe from this list: send the line "unsubscribe kvm-ppc" in
> the body of a message to majordomo@vger•kernel.org
> More majordomo info at http://vger.kernel.org/majordomo-info.html
next prev parent reply other threads:[~2014-05-28 13:12 UTC|newest]
Thread overview: 31+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-05-27 8:40 [PATCH v7 0/3] EEH Support for VFIO PCI Device Gavin Shan
2014-05-27 8:40 ` [PATCH v7 1/3] powerpc/eeh: Avoid event on passed PE Gavin Shan
2014-05-27 8:40 ` [PATCH v7 2/3] powerpc/eeh: EEH support for VFIO PCI device Gavin Shan
2014-05-27 8:40 ` [PATCH v7 3/3] drivers/vfio: " Gavin Shan
2014-05-27 18:15 ` Alex Williamson
2014-05-27 20:30 ` Benjamin Herrenschmidt
2014-05-27 20:37 ` Alex Williamson
2014-05-27 20:41 ` Benjamin Herrenschmidt
2014-05-27 22:49 ` Alexander Graf
2014-05-28 0:39 ` Alex Williamson
2014-05-28 0:44 ` Alexander Graf
2014-05-28 0:57 ` Alex Williamson
2014-05-28 11:37 ` Alexander Graf
2014-05-28 16:17 ` Alex Williamson
2014-05-28 22:40 ` Alexander Graf
2014-05-28 23:37 ` Gavin Shan
2014-05-28 23:38 ` Alexander Graf
2014-05-28 23:41 ` Gavin Shan
2014-05-28 0:55 ` Gavin Shan
2014-05-28 11:41 ` Alexander Graf
2014-05-28 12:49 ` Gavin Shan
2014-05-28 13:12 ` Alexander Graf [this message]
2014-05-28 23:13 ` Gavin Shan
2014-05-28 21:58 ` Benjamin Herrenschmidt
2014-05-28 22:46 ` Alexander Graf
2014-05-28 23:18 ` Benjamin Herrenschmidt
2014-05-30 3:44 ` Alexey Kardashevskiy
2014-05-30 3:49 ` Benjamin Herrenschmidt
2014-05-28 16:32 ` Alex Williamson
2014-05-29 0:05 ` Gavin Shan
2014-05-29 0:44 ` Benjamin Herrenschmidt
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=5385E0C3.8020000@suse.de \
--to=agraf@suse$(echo .)de \
--cc=aik@ozlabs$(echo .)ru \
--cc=alex.williamson@redhat$(echo .)com \
--cc=gwshan@linux$(echo .)vnet.ibm.com \
--cc=kvm-ppc@vger$(echo .)kernel.org \
--cc=linuxppc-dev@lists$(echo .)ozlabs.org \
--cc=qiudayu@linux$(echo .)vnet.ibm.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox