Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755550AbbDJGgv (ORCPT ); Fri, 10 Apr 2015 02:36:51 -0400 Received: from e23smtp03.au.ibm.com ([202.81.31.145]:41948 "EHLO e23smtp03.au.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754340AbbDJGcs (ORCPT ); Fri, 10 Apr 2015 02:32:48 -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 v8 09/31] powerpc/powernv: Do not set "read" flag if direction==DMA_NONE Date: Fri, 10 Apr 2015 16:30:51 +1000 Message-Id: <1428647473-11738-10-git-send-email-aik@ozlabs.ru> X-Mailer: git-send-email 2.0.0 In-Reply-To: <1428647473-11738-1-git-send-email-aik@ozlabs.ru> References: <1428647473-11738-1-git-send-email-aik@ozlabs.ru> X-TM-AS-MML: disable X-Content-Scanned: Fidelis XPS MAILER x-cbid: 15041006-0009-0000-0000-000001332E3A Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2805 Lines: 82 Normally a bitmap from the iommu_table is used to track what TCE entry is in use. Since we are going to use iommu_table without its locks and do xchg() instead, it becomes essential not to put bits which are not implied in the direction flag. This adds iommu_direction_to_tce_perm() (its counterpart is there already) and uses it for powernv's pnv_tce_build(). Signed-off-by: Alexey Kardashevskiy --- arch/powerpc/include/asm/iommu.h | 1 + arch/powerpc/kernel/iommu.c | 15 +++++++++++++++ arch/powerpc/platforms/powernv/pci.c | 7 +------ 3 files changed, 17 insertions(+), 6 deletions(-) diff --git a/arch/powerpc/include/asm/iommu.h b/arch/powerpc/include/asm/iommu.h index ed69b7d..2af2d70 100644 --- a/arch/powerpc/include/asm/iommu.h +++ b/arch/powerpc/include/asm/iommu.h @@ -203,6 +203,7 @@ extern int iommu_take_ownership(struct iommu_table *tbl); extern void iommu_release_ownership(struct iommu_table *tbl); extern enum dma_data_direction iommu_tce_direction(unsigned long tce); +extern unsigned long iommu_direction_to_tce_perm(enum dma_data_direction dir); #endif /* __KERNEL__ */ #endif /* _ASM_IOMMU_H */ diff --git a/arch/powerpc/kernel/iommu.c b/arch/powerpc/kernel/iommu.c index 1b4a178..029b1ea 100644 --- a/arch/powerpc/kernel/iommu.c +++ b/arch/powerpc/kernel/iommu.c @@ -871,6 +871,21 @@ void iommu_free_coherent(struct iommu_table *tbl, size_t size, } } +unsigned long iommu_direction_to_tce_perm(enum dma_data_direction dir) +{ + switch (dir) { + case DMA_BIDIRECTIONAL: + return TCE_PCI_READ | TCE_PCI_WRITE; + case DMA_FROM_DEVICE: + return TCE_PCI_WRITE; + case DMA_TO_DEVICE: + return TCE_PCI_READ; + default: + return 0; + } +} +EXPORT_SYMBOL_GPL(iommu_direction_to_tce_perm); + #ifdef CONFIG_IOMMU_API /* * SPAPR TCE API diff --git a/arch/powerpc/platforms/powernv/pci.c b/arch/powerpc/platforms/powernv/pci.c index 54323d6..609f5b1 100644 --- a/arch/powerpc/platforms/powernv/pci.c +++ b/arch/powerpc/platforms/powernv/pci.c @@ -593,15 +593,10 @@ static int pnv_tce_build(struct iommu_table *tbl, long index, long npages, unsigned long uaddr, enum dma_data_direction direction, struct dma_attrs *attrs, bool rm) { - u64 proto_tce; + u64 proto_tce = iommu_direction_to_tce_perm(direction); __be64 *tcep, *tces; u64 rpn; - proto_tce = TCE_PCI_READ; // Read allowed - - if (direction != DMA_TO_DEVICE) - proto_tce |= TCE_PCI_WRITE; - tces = tcep = ((__be64 *)tbl->it_base) + index - tbl->it_offset; rpn = __pa(uaddr) >> tbl->it_page_shift; -- 2.0.0 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/