Messages in this thread Patch in this message | ![/](/images/icornerl.gif) | | From | Lu Baolu <> | Subject | [PATCH 3/5] iommu/vt-d: Refactor domain_context_mapping_one() to be reusable | Date | Mon, 20 Nov 2023 19:29:42 +0800 |
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Extract common code from domain_context_mapping_one() into new functions, making it reusable by other functions such as the upcoming identity domain implementation. No intentional functional changes.
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> --- drivers/iommu/intel/iommu.c | 99 ++++++++++++++++++++++--------------- 1 file changed, 58 insertions(+), 41 deletions(-)
diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c index 77769ad4706e..86339dc30243 100644 --- a/drivers/iommu/intel/iommu.c +++ b/drivers/iommu/intel/iommu.c @@ -1727,6 +1727,61 @@ static void domain_exit(struct dmar_domain *domain) kfree(domain); } +/* + * For kdump cases, old valid entries may be cached due to the + * in-flight DMA and copied pgtable, but there is no unmapping + * behaviour for them, thus we need an explicit cache flush for + * the newly-mapped device. For kdump, at this point, the device + * is supposed to finish reset at its driver probe stage, so no + * in-flight DMA will exist, and we don't need to worry anymore + * hereafter. + */ +static void copied_context_tear_down(struct intel_iommu *iommu, + struct context_entry *context, + u8 bus, u8 devfn) +{ + u16 did_old; + + if (!context_copied(iommu, bus, devfn)) + return; + + assert_spin_locked(&iommu->lock); + + did_old = context_domain_id(context); + context_clear_entry(context); + + if (did_old < cap_ndoms(iommu->cap)) { + iommu->flush.flush_context(iommu, did_old, + (((u16)bus) << 8) | devfn, + DMA_CCMD_MASK_NOBIT, + DMA_CCMD_DEVICE_INVL); + iommu->flush.flush_iotlb(iommu, did_old, 0, 0, + DMA_TLB_DSI_FLUSH); + } + + clear_context_copied(iommu, bus, devfn); +} + +/* + * It's a non-present to present mapping. If hardware doesn't cache + * non-present entry we only need to flush the write-buffer. If the + * _does_ cache non-present entries, then it does so in the special + * domain #0, which we have to flush: + */ +static void context_present_cache_flush(struct intel_iommu *iommu, u16 did, + u8 bus, u8 devfn) +{ + if (cap_caching_mode(iommu->cap)) { + iommu->flush.flush_context(iommu, 0, + (((u16)bus) << 8) | devfn, + DMA_CCMD_MASK_NOBIT, + DMA_CCMD_DEVICE_INVL); + iommu->flush.flush_iotlb(iommu, did, 0, 0, DMA_TLB_DSI_FLUSH); + } else { + iommu_flush_write_buffer(iommu); + } +} + static int domain_context_mapping_one(struct dmar_domain *domain, struct intel_iommu *iommu, u8 bus, u8 devfn) @@ -1755,31 +1810,9 @@ static int domain_context_mapping_one(struct dmar_domain *domain, if (context_present(context) && !context_copied(iommu, bus, devfn)) goto out_unlock; - /* - * For kdump cases, old valid entries may be cached due to the - * in-flight DMA and copied pgtable, but there is no unmapping - * behaviour for them, thus we need an explicit cache flush for - * the newly-mapped device. For kdump, at this point, the device - * is supposed to finish reset at its driver probe stage, so no - * in-flight DMA will exist, and we don't need to worry anymore - * hereafter. - */ - if (context_copied(iommu, bus, devfn)) { - u16 did_old = context_domain_id(context); - - if (did_old < cap_ndoms(iommu->cap)) { - iommu->flush.flush_context(iommu, did_old, - (((u16)bus) << 8) | devfn, - DMA_CCMD_MASK_NOBIT, - DMA_CCMD_DEVICE_INVL); - iommu->flush.flush_iotlb(iommu, did_old, 0, 0, - DMA_TLB_DSI_FLUSH); - } - - clear_context_copied(iommu, bus, devfn); - } - + copied_context_tear_down(iommu, context, bus, devfn); context_clear_entry(context); + context_set_domain_id(context, did); if (translation != CONTEXT_TT_PASS_THROUGH) { @@ -1815,23 +1848,7 @@ static int domain_context_mapping_one(struct dmar_domain *domain, context_set_present(context); if (!ecap_coherent(iommu->ecap)) clflush_cache_range(context, sizeof(*context)); - - /* - * It's a non-present to present mapping. If hardware doesn't cache - * non-present entry we only need to flush the write-buffer. If the - * _does_ cache non-present entries, then it does so in the special - * domain #0, which we have to flush: - */ - if (cap_caching_mode(iommu->cap)) { - iommu->flush.flush_context(iommu, 0, - (((u16)bus) << 8) | devfn, - DMA_CCMD_MASK_NOBIT, - DMA_CCMD_DEVICE_INVL); - iommu->flush.flush_iotlb(iommu, did, 0, 0, DMA_TLB_DSI_FLUSH); - } else { - iommu_flush_write_buffer(iommu); - } - + context_present_cache_flush(iommu, did, bus, devfn); ret = 0; out_unlock: -- 2.34.1
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