From 41ee7232fa5f3c034f22baa52bc287e494e2129a Mon Sep 17 00:00:00 2001 From: Alexey Kardashevskiy Date: Thu, 21 Oct 2021 00:23:13 +1100 Subject: powerpc/pseries/iommu: Use correct vfree for it_map The it_map array is vzalloc'ed so use vfree() for it when creating a huge DMA window failed for whatever reason. While at this, write zero to it_map. Fixes: 381ceda88c4c ("powerpc/pseries/iommu: Make use of DDW for indirect mapping") Signed-off-by: Alexey Kardashevskiy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20211020132315.2287178-3-aik@ozlabs.ru --- arch/powerpc/platforms/pseries/iommu.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/arch/powerpc/platforms/pseries/iommu.c b/arch/powerpc/platforms/pseries/iommu.c index dab5c56ffd0e..c003f698eedd 100644 --- a/arch/powerpc/platforms/pseries/iommu.c +++ b/arch/powerpc/platforms/pseries/iommu.c @@ -1440,7 +1440,8 @@ static bool enable_ddw(struct pci_dev *dev, struct device_node *pdn) /* Keep default DMA window stuct if removed */ if (default_win_removed) { tbl->it_size = 0; - kfree(tbl->it_map); + vfree(tbl->it_map); + tbl->it_map = NULL; } set_iommu_table_base(&dev->dev, newtbl); -- cgit v1.2.3 From 92fe01b7c655b9767724e7d62bdded0761d232ff Mon Sep 17 00:00:00 2001 From: Alexey Kardashevskiy Date: Thu, 21 Oct 2021 00:23:14 +1100 Subject: powerpc/pseries/iommu: Check if the default window in use before removing it At the moment this check is performed after we remove the default window which is late and disallows to revert whatever changes enable_ddw() has made to DMA windows. This moves the check and error exit before removing the window. This raised the message severity from "debug" to "warning" as this should not happen in practice and cannot be triggered by the userspace. Fixes: 381ceda88c4c ("powerpc/pseries/iommu: Make use of DDW for indirect mapping") Signed-off-by: Alexey Kardashevskiy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20211020132315.2287178-4-aik@ozlabs.ru --- arch/powerpc/platforms/pseries/iommu.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/arch/powerpc/platforms/pseries/iommu.c b/arch/powerpc/platforms/pseries/iommu.c index c003f698eedd..8f921e38ce74 100644 --- a/arch/powerpc/platforms/pseries/iommu.c +++ b/arch/powerpc/platforms/pseries/iommu.c @@ -1302,6 +1302,12 @@ static bool enable_ddw(struct pci_dev *dev, struct device_node *pdn) struct property *default_win; int reset_win_ext; + /* DDW + IOMMU on single window may fail if there is any allocation */ + if (iommu_table_in_use(tbl)) { + dev_warn(&dev->dev, "current IOMMU table in use, can't be replaced.\n"); + goto out_failed; + } + default_win = of_find_property(pdn, "ibm,dma-window", NULL); if (!default_win) goto out_failed; @@ -1356,12 +1362,6 @@ static bool enable_ddw(struct pci_dev *dev, struct device_node *pdn) query.largest_available_block, 1ULL << page_shift); - /* DDW + IOMMU on single window may fail if there is any allocation */ - if (default_win_removed && iommu_table_in_use(tbl)) { - dev_dbg(&dev->dev, "current IOMMU table in use, can't be replaced.\n"); - goto out_failed; - } - len = order_base_2(query.largest_available_block << page_shift); win_name = DMA64_PROPNAME; } else { -- cgit v1.2.3 From d853adc7adf601d7d6823afe3ed396065a3e08d1 Mon Sep 17 00:00:00 2001 From: Alexey Kardashevskiy Date: Thu, 21 Oct 2021 00:23:15 +1100 Subject: powerpc/pseries/iommu: Create huge DMA window if no MMIO32 is present The iommu_init_table() helper takes an address range to reserve in the IOMMU table being initialized to exclude MMIO addresses, this is useful if the window stretches far beyond 4GB (although wastes some TCEs). At the moment the code searches for such MMIO32 range and fails if none found which is considered a problem while it really is not: it is actually better as this says there is no MMIO32 to reserve and we can use usually wasted TCEs. Furthermore PHYP never actually allows creating windows starting at busaddress=0 so this MMIO32 range is never useful. This removes error exit and initializes the table with zero range if no MMIO32 is detected. Fixes: 381ceda88c4c ("powerpc/pseries/iommu: Make use of DDW for indirect mapping") Signed-off-by: Alexey Kardashevskiy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20211020132315.2287178-5-aik@ozlabs.ru --- arch/powerpc/platforms/pseries/iommu.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/arch/powerpc/platforms/pseries/iommu.c b/arch/powerpc/platforms/pseries/iommu.c index 8f921e38ce74..a52af8fbf571 100644 --- a/arch/powerpc/platforms/pseries/iommu.c +++ b/arch/powerpc/platforms/pseries/iommu.c @@ -1411,18 +1411,19 @@ static bool enable_ddw(struct pci_dev *dev, struct device_node *pdn) } else { struct iommu_table *newtbl; int i; + unsigned long start = 0, end = 0; for (i = 0; i < ARRAY_SIZE(pci->phb->mem_resources); i++) { const unsigned long mask = IORESOURCE_MEM_64 | IORESOURCE_MEM; /* Look for MMIO32 */ - if ((pci->phb->mem_resources[i].flags & mask) == IORESOURCE_MEM) + if ((pci->phb->mem_resources[i].flags & mask) == IORESOURCE_MEM) { + start = pci->phb->mem_resources[i].start; + end = pci->phb->mem_resources[i].end; break; + } } - if (i == ARRAY_SIZE(pci->phb->mem_resources)) - goto out_del_list; - /* New table for using DDW instead of the default DMA window */ newtbl = iommu_pseries_alloc_table(pci->phb->node); if (!newtbl) { @@ -1432,8 +1433,7 @@ static bool enable_ddw(struct pci_dev *dev, struct device_node *pdn) iommu_table_setparms_common(newtbl, pci->phb->bus->number, create.liobn, win_addr, 1UL << len, page_shift, NULL, &iommu_table_lpar_multi_ops); - iommu_init_table(newtbl, pci->phb->node, pci->phb->mem_resources[i].start, - pci->phb->mem_resources[i].end); + iommu_init_table(newtbl, pci->phb->node, start, end); pci->table_group->tables[1] = newtbl; -- cgit v1.2.3