From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Burakov, Anatoly" Subject: Re: [PATCH v2] vfio: allow secondary process to query IOMMU type Date: Mon, 21 Jan 2019 10:13:24 +0000 Message-ID: <1b5e395c-1d0e-ffd4-3eb5-8e1d4f77152d@intel.com> References: <2101fda2f9030723c662419ec9b4a33d2dc7aded.1547807046.git.anatoly.burakov@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Cc: "Zhang, Qi Z" , "qingfu.cqf@alibaba-inc.com" , "thomas@monjalon.net" , "Stojaczyk, Dariusz" , "stable@dpdk.org" To: "Wang, Xiao W" , "dev@dpdk.org" Return-path: In-Reply-To: Content-Language: en-US List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" 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@dpdk.org >> Cc: Wang, Xiao W ; Zhang, Qi Z >> ; qingfu.cqf@alibaba-inc.com; thomas@monjalon.net; >> Stojaczyk, Dariusz ; stable@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@intel.com >> Cc: stable@dpdk.org >> >> Signed-off-by: Anatoly Burakov >> --- >> >> 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