[dpdk-stable] [PATCH v2] vfio: allow secondary process to query IOMMU type
Burakov, Anatoly
anatoly.burakov at intel.com
Mon Jan 21 11:13:24 CET 2019
On 19-Jan-19 3:23 AM, Wang, Xiao W wrote:
> Hi Anatoly,
>
>> -----Original Message-----
>> From: Burakov, Anatoly
>> Sent: Friday, January 18, 2019 6:25 PM
>> To: dev at dpdk.org
>> Cc: Wang, Xiao W <xiao.w.wang at intel.com>; Zhang, Qi Z
>> <qi.z.zhang at intel.com>; qingfu.cqf at alibaba-inc.com; thomas at monjalon.net;
>> Stojaczyk, Dariusz <dariusz.stojaczyk at intel.com>; stable at dpdk.org
>> Subject: [PATCH v2] vfio: allow secondary process to query IOMMU type
>>
>> It is only possible to know IOMMU type of a given VFIO container
>> by attempting to initialize it. Since secondary process never
>> attempts to set up VFIO container itself (because they're shared
>> between primary and secondary), it never knows which IOMMU type
>> the container is using, and never sets up the appropriate config
>> structures. This results in inability to perform DMA mappings in
>> secondary process.
>>
>> Fix this by allowing secondary process to query IOMMU type of
>> primary's default container at device initialization.
>>
>> Note that this fix is assuming we're only interested in default
>> container.
>>
>> Bugzilla ID: 174
>>
>> Fixes: 6bcb7c95fe14 ("vfio: share default container in multi-process")
>> Cc: dariusz.stojaczyk at intel.com
>> Cc: stable at dpdk.org
>>
>> Signed-off-by: Anatoly Burakov <anatoly.burakov at intel.com>
>> ---
>>
>> Notes:
>> v2:
>> - Check if we found our IOMMU type within list of IOMMU types
>> - Don't request new default container fd as this should have
>> been done during rte_vfio_enable()
>>
>> lib/librte_eal/linuxapp/eal/eal_vfio.c | 88 +++++++++++++++++++
>> lib/librte_eal/linuxapp/eal/eal_vfio.h | 12 ++-
>> .../linuxapp/eal/eal_vfio_mp_sync.c | 16 ++++
>> 3 files changed, 115 insertions(+), 1 deletion(-)
>>
>> diff --git a/lib/librte_eal/linuxapp/eal/eal_vfio.c
>> b/lib/librte_eal/linuxapp/eal/eal_vfio.c
>> index 72cc65151..c821e8382 100644
>> --- a/lib/librte_eal/linuxapp/eal/eal_vfio.c
>> +++ b/lib/librte_eal/linuxapp/eal/eal_vfio.c
>> @@ -549,6 +549,65 @@ vfio_mem_event_callback(enum rte_mem_event
>> type, const void *addr, size_t len,
>> }
>> }
>>
>> +static int
>> +vfio_sync_default_container(void)
>> +{
>> + struct rte_mp_msg mp_req, *mp_rep;
>> + struct rte_mp_reply mp_reply;
>> + struct timespec ts = {.tv_sec = 5, .tv_nsec = 0};
>> + struct vfio_mp_param *p = (struct vfio_mp_param *)mp_req.param;
>> + int iommu_type_id;
>> + unsigned int i;
>> +
>> + /* cannot be called from primary */
>> + if (rte_eal_process_type() != RTE_PROC_SECONDARY)
>> + return -1;
>> +
>> + /* default container fd should have been opened in rte_vfio_enable()
>> */
>> + if (!default_vfio_cfg->vfio_enabled ||
>> + default_vfio_cfg->vfio_container_fd < 0) {
>> + RTE_LOG(ERR, EAL, "VFIO support is not initialized\n");
>> + return -1;
>> + }
>> +
>> + /* find default container's IOMMU type */
>> + p->req = SOCKET_REQ_IOMMU_TYPE;
>
> Since this function is to sync IOMMU type for the default container, should we make the req type as
> SOCKET_REQ_DEFAULT_IOMMU_TYPE?
Hi,
Sure, that can be done. However, i don't think it warrants a respin
unless there's more important stuff to fix also. This patch is a
stop-gap, and this stuff will be rewritten for 19.05, so getting this
right is not that important :).
>
> BRs,
> Xiao
>
--
Thanks,
Anatoly
More information about the stable
mailing list