From 7c53664dcd5df7349edb56f04c743bf66510a6f1 Mon Sep 17 00:00:00 2001 From: FUJITA Tomonori Date: Mon, 4 Feb 2008 22:27:58 -0800 Subject: iommu sg merging: alpha: make pci_iommu respect the segment size limits This patch makes pci_iommu respect segment size limits when merging sg lists. Signed-off-by: FUJITA Tomonori Cc: Jeff Garzik Cc: James Bottomley Acked-by: Jens Axboe Cc: Richard Henderson Cc: Ivan Kokshaysky Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/alpha/kernel/pci_iommu.c | 24 ++++++++++++++++++------ 1 file changed, 18 insertions(+), 6 deletions(-) (limited to 'arch/alpha/kernel/pci_iommu.c') diff --git a/arch/alpha/kernel/pci_iommu.c b/arch/alpha/kernel/pci_iommu.c index 2d00a08d3f08..26d3789dfdd0 100644 --- a/arch/alpha/kernel/pci_iommu.c +++ b/arch/alpha/kernel/pci_iommu.c @@ -9,6 +9,7 @@ #include #include #include +#include #include #include @@ -470,22 +471,29 @@ EXPORT_SYMBOL(pci_free_consistent); #define SG_ENT_PHYS_ADDRESS(SG) __pa(SG_ENT_VIRT_ADDRESS(SG)) static void -sg_classify(struct scatterlist *sg, struct scatterlist *end, int virt_ok) +sg_classify(struct device *dev, struct scatterlist *sg, struct scatterlist *end, + int virt_ok) { unsigned long next_paddr; struct scatterlist *leader; long leader_flag, leader_length; + unsigned int max_seg_size; leader = sg; leader_flag = 0; leader_length = leader->length; next_paddr = SG_ENT_PHYS_ADDRESS(leader) + leader_length; + /* we will not marge sg without device. */ + max_seg_size = dev ? dma_get_max_seg_size(dev) : 0; for (++sg; sg < end; ++sg) { unsigned long addr, len; addr = SG_ENT_PHYS_ADDRESS(sg); len = sg->length; + if (leader_length + len > max_seg_size) + goto new_segment; + if (next_paddr == addr) { sg->dma_address = -1; leader_length += len; @@ -494,6 +502,7 @@ sg_classify(struct scatterlist *sg, struct scatterlist *end, int virt_ok) leader_flag = 1; leader_length += len; } else { +new_segment: leader->dma_address = leader_flag; leader->dma_length = leader_length; leader = sg; @@ -512,7 +521,7 @@ sg_classify(struct scatterlist *sg, struct scatterlist *end, int virt_ok) in the blanks. */ static int -sg_fill(struct scatterlist *leader, struct scatterlist *end, +sg_fill(struct device *dev, struct scatterlist *leader, struct scatterlist *end, struct scatterlist *out, struct pci_iommu_arena *arena, dma_addr_t max_dma, int dac_allowed) { @@ -562,8 +571,8 @@ sg_fill(struct scatterlist *leader, struct scatterlist *end, /* Otherwise, break up the remaining virtually contiguous hunks into individual direct maps and retry. */ - sg_classify(leader, end, 0); - return sg_fill(leader, end, out, arena, max_dma, dac_allowed); + sg_classify(dev, leader, end, 0); + return sg_fill(dev, leader, end, out, arena, max_dma, dac_allowed); } out->dma_address = arena->dma_base + dma_ofs*PAGE_SIZE + paddr; @@ -619,12 +628,15 @@ pci_map_sg(struct pci_dev *pdev, struct scatterlist *sg, int nents, struct pci_iommu_arena *arena; dma_addr_t max_dma; int dac_allowed; + struct device *dev; if (direction == PCI_DMA_NONE) BUG(); dac_allowed = pdev ? pci_dac_dma_supported(pdev, pdev->dma_mask) : 0; + dev = pdev ? &pdev->dev : NULL; + /* Fast path single entry scatterlists. */ if (nents == 1) { sg->dma_length = sg->length; @@ -638,7 +650,7 @@ pci_map_sg(struct pci_dev *pdev, struct scatterlist *sg, int nents, end = sg + nents; /* First, prepare information about the entries. */ - sg_classify(sg, end, alpha_mv.mv_pci_tbi != 0); + sg_classify(dev, sg, end, alpha_mv.mv_pci_tbi != 0); /* Second, figure out where we're going to map things. */ if (alpha_mv.mv_pci_tbi) { @@ -658,7 +670,7 @@ pci_map_sg(struct pci_dev *pdev, struct scatterlist *sg, int nents, for (out = sg; sg < end; ++sg) { if ((int) sg->dma_address < 0) continue; - if (sg_fill(sg, end, out, arena, max_dma, dac_allowed) < 0) + if (sg_fill(dev, sg, end, out, arena, max_dma, dac_allowed) < 0) goto error; out++; } -- cgit