From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932142AbbC0O50 (ORCPT ); Fri, 27 Mar 2015 10:57:26 -0400 Received: from e23smtp01.au.ibm.com ([202.81.31.143]:38128 "EHLO e23smtp01.au.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753574AbbC0O5V (ORCPT ); Fri, 27 Mar 2015 10:57:21 -0400 From: Alexey Kardashevskiy To: linuxppc-dev@lists.ozlabs.org Cc: Alexey Kardashevskiy , Benjamin Herrenschmidt , Paul Mackerras , Alex Williamson , linux-kernel@vger.kernel.org Subject: [PATCH kernel v7 25/31] vfio: powerpc/spapr: powerpc/powernv/ioda2: Rework ownership Date: Sat, 28 Mar 2015 01:55:09 +1100 Message-Id: <1427468115-2224-26-git-send-email-aik@ozlabs.ru> X-Mailer: git-send-email 2.0.0 In-Reply-To: <1427468115-2224-1-git-send-email-aik@ozlabs.ru> References: <1427468115-2224-1-git-send-email-aik@ozlabs.ru> X-TM-AS-MML: disable X-Content-Scanned: Fidelis XPS MAILER x-cbid: 15032714-1618-0000-0000-000001D247EF Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Before the IOMMU user (VFIO) would take control over the IOMMU table belonging to a specific IOMMU group. This approach did not allow sharing tables between IOMMU groups attached to the same container. This introduces a new IOMMU ownership flavour when the user can not just control the existing IOMMU table but remove/create tables on demand. If an IOMMU implements a set_ownership() callback, this lets the user have full control over the IOMMU group. When the ownership is taken, the platform code removes all the windows so the caller must create them. Before returning the ownership back to the platform code, VFIO unprograms and removes all the tables it created. Old-style ownership is still supported allowing VFIO to run on older P5IOC2 and IODA IO controllers. Signed-off-by: Alexey Kardashevskiy --- Changes: v6: * fixed commit log that VFIO removes tables before passing ownership back to the platform code, not userspace --- arch/powerpc/platforms/powernv/pci-ioda.c | 30 +++++++++++++++--- drivers/vfio/vfio_iommu_spapr_tce.c | 51 ++++++++++++++++++++++++------- 2 files changed, 66 insertions(+), 15 deletions(-) diff --git a/arch/powerpc/platforms/powernv/pci-ioda.c b/arch/powerpc/platforms/powernv/pci-ioda.c index 6939402..bc36cf1 100644 --- a/arch/powerpc/platforms/powernv/pci-ioda.c +++ b/arch/powerpc/platforms/powernv/pci-ioda.c @@ -1626,11 +1626,33 @@ static void pnv_ioda2_set_ownership(struct iommu_table_group *table_group, { struct pnv_ioda_pe *pe = container_of(table_group, struct pnv_ioda_pe, table_group); - if (enable) - iommu_take_ownership(table_group); - else - iommu_release_ownership(table_group); + if (enable) { + pnv_pci_ioda2_unset_window(&pe->table_group, 0); + pnv_pci_free_table(&pe->table_group.tables[0]); + } else { + struct iommu_table *tbl = &pe->table_group.tables[0]; + int64_t rc; + rc = pnv_pci_ioda2_create_table(&pe->table_group, 0, + IOMMU_PAGE_SHIFT_4K, + pe->phb->ioda.m32_pci_base, + POWERNV_IOMMU_DEFAULT_LEVELS, tbl); + if (rc) { + pe_err(pe, "Failed to create 32-bit TCE table, err %ld", + rc); + return; + } + + iommu_init_table(tbl, pe->phb->hose->node); + + rc = pnv_pci_ioda2_set_window(&pe->table_group, 0, tbl); + if (rc) { + pe_err(pe, "Failed to configure 32-bit TCE table, err %ld\n", + rc); + pnv_pci_free_table(tbl); + return; + } + } pnv_pci_ioda2_set_bypass(pe, !enable); } diff --git a/drivers/vfio/vfio_iommu_spapr_tce.c b/drivers/vfio/vfio_iommu_spapr_tce.c index 7c3c215..9aeaed6 100644 --- a/drivers/vfio/vfio_iommu_spapr_tce.c +++ b/drivers/vfio/vfio_iommu_spapr_tce.c @@ -226,18 +226,11 @@ static int tce_iommu_clear(struct tce_container *container, static void tce_iommu_release(void *iommu_data) { struct tce_container *container = iommu_data; - struct iommu_table *tbl; - struct iommu_table_group *table_group; WARN_ON(container->grp); - if (container->grp) { - table_group = iommu_group_get_iommudata(container->grp); - tbl = &table_group->tables[0]; - tce_iommu_clear(container, tbl, tbl->it_offset, tbl->it_size); - + if (container->grp) tce_iommu_detach_group(iommu_data, container->grp); - } tce_iommu_disable(container); @@ -553,14 +546,24 @@ static int tce_iommu_attach_group(void *iommu_data, if (!table_group->ops || !table_group->ops->set_ownership) { ret = iommu_take_ownership(table_group); + } else if (!table_group->ops->create_table || + !table_group->ops->set_window) { + WARN_ON_ONCE(1); + ret = -EFAULT; } else { /* * Disable iommu bypass, otherwise the user can DMA to all of * our physical memory via the bypass window instead of just * the pages that has been explicitly mapped into the iommu */ + struct iommu_table tbltmp = { 0 }, *tbl = &tbltmp; + table_group->ops->set_ownership(table_group, true); - ret = 0; + ret = table_group->ops->create_table(table_group, 0, + IOMMU_PAGE_SHIFT_4K, + table_group->tce32_size, 1, tbl); + if (!ret) + ret = table_group->ops->set_window(table_group, 0, tbl); } if (ret) @@ -579,6 +582,7 @@ static void tce_iommu_detach_group(void *iommu_data, { struct tce_container *container = iommu_data; struct iommu_table_group *table_group; + long i; mutex_lock(&container->lock); if (iommu_group != container->grp) { @@ -602,10 +606,35 @@ static void tce_iommu_detach_group(void *iommu_data, BUG_ON(!table_group); /* Kernel owns the device now, we can restore bypass */ - if (!table_group->ops || !table_group->ops->set_ownership) + if (!table_group->ops || !table_group->ops->set_ownership) { + for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i) { + struct iommu_table *tbl = &table_group->tables[i]; + + if (!tbl->it_size) + continue; + + if (!tbl->it_ops) + goto unlock_exit; + tce_iommu_clear(container, tbl, + tbl->it_offset, tbl->it_size); + } iommu_release_ownership(table_group); - else + } else if (!table_group->ops->unset_window) { + WARN_ON_ONCE(1); + } else { + for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i) { + struct iommu_table *tbl = &table_group->tables[i]; + + table_group->ops->unset_window(table_group, i); + tce_iommu_clear(container, tbl, + tbl->it_offset, tbl->it_size); + + if (tbl->it_ops->free) + tbl->it_ops->free(tbl); + } + table_group->ops->set_ownership(table_group, false); + } unlock_exit: mutex_unlock(&container->lock); -- 2.0.0