From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756708AbYIQQ4k (ORCPT ); Wed, 17 Sep 2008 12:56:40 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755254AbYIQQxU (ORCPT ); Wed, 17 Sep 2008 12:53:20 -0400 Received: from outbound-sin.frontbridge.com ([207.46.51.80]:53008 "EHLO SG2EHSOBE006.bigfish.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755131AbYIQQxR (ORCPT ); Wed, 17 Sep 2008 12:53:17 -0400 X-BigFish: VPS4(zzzz10d3izzz32i43j62h) X-Spam-TCS-SCL: 1:0 X-WSS-ID: 0K7CMWB-04-US4-01 From: Joerg Roedel To: linux-kernel@vger.kernel.org CC: iommu@lists.linux-foundation.org, Joerg Roedel Subject: [PATCH 14/23] AMD IOMMU: don't assing preallocated protection domains to devices Date: Wed, 17 Sep 2008 18:52:48 +0200 Message-ID: <1221670377-19295-15-git-send-email-joerg.roedel@amd.com> X-Mailer: git-send-email 1.5.6.4 In-Reply-To: <1221670377-19295-1-git-send-email-joerg.roedel@amd.com> References: <1221670377-19295-1-git-send-email-joerg.roedel@amd.com> X-OriginalArrivalTime: 17 Sep 2008 16:52:58.0126 (UTC) FILETIME=[D673CAE0:01C918E5] MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org In isolation mode the protection domains for the devices are preallocated and preassigned. This is bad if a device should be passed to a virtualization guest because the IOMMU code does not know if it is in use by a driver. This patch changes the code to assign the device to the preallocated domain only if there were dma mapping requests for it. Signed-off-by: Joerg Roedel --- arch/x86/kernel/amd_iommu.c | 43 ++++++++++++++++++++++++++++++++---- include/asm-x86/amd_iommu_types.h | 6 +++++ 2 files changed, 44 insertions(+), 5 deletions(-) diff --git a/arch/x86/kernel/amd_iommu.c b/arch/x86/kernel/amd_iommu.c index 0410be1..09d5e92 100644 --- a/arch/x86/kernel/amd_iommu.c +++ b/arch/x86/kernel/amd_iommu.c @@ -33,6 +33,10 @@ static DEFINE_RWLOCK(amd_iommu_devtable_lock); +/* A list of preallocated protection domains */ +static LIST_HEAD(iommu_pd_list); +static DEFINE_SPINLOCK(iommu_pd_list_lock); + /* * general struct to manage commands send to an IOMMU */ @@ -663,6 +667,7 @@ static struct dma_ops_domain *dma_ops_domain_alloc(struct amd_iommu *iommu, dma_dom->next_bit = 0; dma_dom->need_flush = false; + dma_dom->target_dev = 0xffff; /* Intialize the exclusion range if necessary */ if (iommu->exclusion_start && @@ -769,6 +774,33 @@ static bool check_device(struct device *dev) } /* + * In this function the list of preallocated protection domains is traversed to + * find the domain for a specific device + */ +static struct dma_ops_domain *find_protection_domain(u16 devid) +{ + struct dma_ops_domain *entry, *ret = NULL; + unsigned long flags; + + if (list_empty(&iommu_pd_list)) + return NULL; + + spin_lock_irqsave(&iommu_pd_list_lock, flags); + + list_for_each_entry(entry, &iommu_pd_list, list) { + if (entry->target_dev == devid) { + ret = entry; + list_del(&ret->list); + break; + } + } + + spin_unlock_irqrestore(&iommu_pd_list_lock, flags); + + return ret; +} + +/* * In the dma_ops path we only have the struct device. This function * finds the corresponding IOMMU, the protection domain and the * requestor id for a given device. @@ -803,9 +835,11 @@ static int get_device_resources(struct device *dev, *iommu = amd_iommu_rlookup_table[*bdf]; if (*iommu == NULL) return 0; - dma_dom = (*iommu)->default_dom; *domain = domain_for_device(*bdf); if (*domain == NULL) { + dma_dom = find_protection_domain(*bdf); + if (!dma_dom) + dma_dom = (*iommu)->default_dom; *domain = &dma_dom->domain; set_device_domain(*iommu, *domain, *bdf); printk(KERN_INFO "AMD IOMMU: Using protection domain %d for " @@ -1257,10 +1291,9 @@ void prealloc_protection_domains(void) if (!dma_dom) continue; init_unity_mappings_for_device(dma_dom, devid); - set_device_domain(iommu, &dma_dom->domain, devid); - printk(KERN_INFO "AMD IOMMU: Allocated domain %d for device ", - dma_dom->domain.id); - print_devid(devid, 1); + dma_dom->target_dev = devid; + + list_add_tail(&dma_dom->list, &iommu_pd_list); } } diff --git a/include/asm-x86/amd_iommu_types.h b/include/asm-x86/amd_iommu_types.h index 1c9d8d4..56dc6bd 100644 --- a/include/asm-x86/amd_iommu_types.h +++ b/include/asm-x86/amd_iommu_types.h @@ -227,6 +227,12 @@ struct dma_ops_domain { /* This will be set to true when TLB needs to be flushed */ bool need_flush; + + /* + * if this is a preallocated domain, keep the device for which it was + * preallocated in this variable + */ + u16 target_dev; }; /* -- 1.5.6.4