diff --git a/drivers/iommu/io-pgtable-arm.c b/drivers/iommu/io-pgtable-arm.c index 2f79efd16a05..237cacd4a62b 100644 --- a/drivers/iommu/io-pgtable-arm.c +++ b/drivers/iommu/io-pgtable-arm.c @@ -576,6 +576,7 @@ static size_t arm_lpae_split_blk_unmap(struct arm_lpae_io_pgtable *data, tablep = iopte_deref(pte, data); } else if (unmap_idx >= 0) { io_pgtable_tlb_add_flush(&data->iop, iova, size, size, true); + io_pgtable_tlb_sync(&data->iop); return size; } @@ -609,6 +610,13 @@ static size_t __arm_lpae_unmap(struct arm_lpae_io_pgtable *data, io_pgtable_tlb_sync(iop); ptep = iopte_deref(pte, data); __arm_lpae_free_pgtable(data, lvl + 1, ptep); + } else if (iop->cfg.quirks & IO_PGTABLE_QUIRK_NON_STRICT) { + /* + * Order the PTE update against queueing the IOVA, to + * guarantee that a flush callback from a different CPU + * has observed it before the TLBIALL can be issued. + */ + smp_wmb(); } else { io_pgtable_tlb_add_flush(iop, iova, size, size, true); } @@ -771,7 +779,8 @@ arm_64_lpae_alloc_pgtable_s1(struct io_pgtable_cfg *cfg, void *cookie) u64 reg; struct arm_lpae_io_pgtable *data; - if (cfg->quirks & ~(IO_PGTABLE_QUIRK_ARM_NS | IO_PGTABLE_QUIRK_NO_DMA)) + if (cfg->quirks & ~(IO_PGTABLE_QUIRK_ARM_NS | IO_PGTABLE_QUIRK_NO_DMA | + IO_PGTABLE_QUIRK_NON_STRICT)) return NULL; data = arm_lpae_alloc_pgtable(cfg); @@ -863,7 +872,8 @@ arm_64_lpae_alloc_pgtable_s2(struct io_pgtable_cfg *cfg, void *cookie) struct arm_lpae_io_pgtable *data; /* The NS quirk doesn't apply at stage 2 */ - if (cfg->quirks & ~IO_PGTABLE_QUIRK_NO_DMA) + if (cfg->quirks & ~(IO_PGTABLE_QUIRK_NO_DMA | + IO_PGTABLE_QUIRK_NON_STRICT)) return NULL; data = arm_lpae_alloc_pgtable(cfg); diff --git a/drivers/iommu/io-pgtable.h b/drivers/iommu/io-pgtable.h index 2df79093cad9..47d5ae559329 100644 --- a/drivers/iommu/io-pgtable.h +++ b/drivers/iommu/io-pgtable.h @@ -71,12 +71,17 @@ struct io_pgtable_cfg { * be accessed by a fully cache-coherent IOMMU or CPU (e.g. for a * software-emulated IOMMU), such that pagetable updates need not * be treated as explicit DMA data. + * + * IO_PGTABLE_QUIRK_NON_STRICT: Skip issuing synchronous leaf TLBIs + * on unmap, for DMA domains using the flush queue mechanism for + * delayed invalidation. */ #define IO_PGTABLE_QUIRK_ARM_NS BIT(0) #define IO_PGTABLE_QUIRK_NO_PERMS BIT(1) #define IO_PGTABLE_QUIRK_TLBI_ON_MAP BIT(2) #define IO_PGTABLE_QUIRK_ARM_MTK_4GB BIT(3) #define IO_PGTABLE_QUIRK_NO_DMA BIT(4) + #define IO_PGTABLE_QUIRK_NON_STRICT BIT(5) unsigned long quirks; unsigned long pgsize_bitmap; unsigned int ias;