From b4ae4430ab402cf7cace55ba97fbd4f392f00d2b Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Sat, 8 May 2021 13:00:33 +0200 Subject: [PATCH] Revert "swiotlb: respect min_align_mask" This reverts commit f8e71c667ee12094b50f5a935133d080740cd66b. Fixes the ABI issues in 5.10.35 that at the moment, we can't handle due to the KABI freeze. These are not patches that mean much for android systems, and will be reverted the next KABI "reset" point. Bug: 161946584 Signed-off-by: Greg Kroah-Hartman Change-Id: I6684b40d913a86b79899220cba823a74aea5923f --- kernel/dma/swiotlb.c | 41 ++++++++++------------------------------- 1 file changed, 10 insertions(+), 31 deletions(-) diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c index ba4055a192e4..b8f82f96c4c2 100644 --- a/kernel/dma/swiotlb.c +++ b/kernel/dma/swiotlb.c @@ -454,14 +454,6 @@ static void swiotlb_bounce(phys_addr_t orig_addr, phys_addr_t tlb_addr, #define slot_addr(start, idx) ((start) + ((idx) << IO_TLB_SHIFT)) -/* - * Return the offset into a iotlb slot required to keep the device happy. - */ -static unsigned int swiotlb_align_offset(struct device *dev, u64 addr) -{ - return addr & dma_get_min_align_mask(dev) & (IO_TLB_SIZE - 1); -} - /* * Carefully handle integer overflow which can occur when boundary_mask == ~0UL. */ @@ -483,29 +475,24 @@ static unsigned int wrap_index(unsigned int index) * Find a suitable number of IO TLB entries size that will fit this request and * allocate a buffer from that IO TLB pool. */ -static int find_slots(struct device *dev, phys_addr_t orig_addr, - size_t alloc_size) +static int find_slots(struct device *dev, size_t alloc_size) { unsigned long boundary_mask = dma_get_seg_boundary(dev); dma_addr_t tbl_dma_addr = phys_to_dma_unencrypted(dev, io_tlb_start) & boundary_mask; unsigned long max_slots = get_max_slots(boundary_mask); - unsigned int iotlb_align_mask = - dma_get_min_align_mask(dev) & ~(IO_TLB_SIZE - 1); - unsigned int nslots = nr_slots(alloc_size), stride; + unsigned int nslots = nr_slots(alloc_size), stride = 1; unsigned int index, wrap, count = 0, i; unsigned long flags; BUG_ON(!nslots); /* - * For mappings with an alignment requirement don't bother looping to - * unaligned slots once we found an aligned one. For allocations of - * PAGE_SIZE or larger only look for page aligned allocations. + * For mappings greater than or equal to a page, we limit the stride + * (and hence alignment) to a page size. */ - stride = (iotlb_align_mask >> IO_TLB_SHIFT) + 1; if (alloc_size >= PAGE_SIZE) - stride = max(stride, stride << (PAGE_SHIFT - IO_TLB_SHIFT)); + stride <<= (PAGE_SHIFT - IO_TLB_SHIFT); spin_lock_irqsave(&io_tlb_lock, flags); if (unlikely(nslots > io_tlb_nslabs - io_tlb_used)) @@ -513,12 +500,6 @@ static int find_slots(struct device *dev, phys_addr_t orig_addr, index = wrap = wrap_index(ALIGN(io_tlb_index, stride)); do { - if ((slot_addr(tbl_dma_addr, index) & iotlb_align_mask) != - (orig_addr & iotlb_align_mask)) { - index = wrap_index(index + 1); - continue; - } - /* * If we find a slot that indicates we have 'nslots' number of * contiguous buffers, we allocate the buffers from that slot @@ -562,7 +543,6 @@ phys_addr_t swiotlb_tbl_map_single(struct device *dev, phys_addr_t orig_addr, size_t mapping_size, size_t alloc_size, enum dma_data_direction dir, unsigned long attrs) { - unsigned int offset = swiotlb_align_offset(dev, orig_addr); unsigned int index, i; phys_addr_t tlb_addr; @@ -578,7 +558,7 @@ phys_addr_t swiotlb_tbl_map_single(struct device *dev, phys_addr_t orig_addr, return (phys_addr_t)DMA_MAPPING_ERROR; } - index = find_slots(dev, orig_addr, alloc_size + offset); + index = find_slots(dev, alloc_size); if (index == -1) { if (!(attrs & DMA_ATTR_NO_WARN)) dev_warn_ratelimited(dev, @@ -592,10 +572,10 @@ phys_addr_t swiotlb_tbl_map_single(struct device *dev, phys_addr_t orig_addr, * This is needed when we sync the memory. Then we sync the buffer if * needed. */ - for (i = 0; i < nr_slots(alloc_size + offset); i++) + for (i = 0; i < nr_slots(alloc_size); i++) io_tlb_orig_addr[index + i] = slot_addr(orig_addr, i); - tlb_addr = slot_addr(io_tlb_start, index) + offset; + tlb_addr = slot_addr(io_tlb_start, index); if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC) && (dir == DMA_TO_DEVICE || dir == DMA_BIDIRECTIONAL)) swiotlb_bounce(orig_addr, tlb_addr, mapping_size, DMA_TO_DEVICE); @@ -610,9 +590,8 @@ void swiotlb_tbl_unmap_single(struct device *hwdev, phys_addr_t tlb_addr, enum dma_data_direction dir, unsigned long attrs) { unsigned long flags; - unsigned int offset = swiotlb_align_offset(hwdev, tlb_addr); - int i, count, nslots = nr_slots(alloc_size + offset); - int index = (tlb_addr - offset - io_tlb_start) >> IO_TLB_SHIFT; + int i, count, nslots = nr_slots(alloc_size); + int index = (tlb_addr - io_tlb_start) >> IO_TLB_SHIFT; phys_addr_t orig_addr = io_tlb_orig_addr[index]; /*