Copy the pages duing SVM migration using memcpy().
Cc: Joonas Lahtinen joonas.lahtinen@linux.intel.com Cc: Jon Bloomfield jon.bloomfield@intel.com Cc: Daniel Vetter daniel.vetter@intel.com Cc: Sudeep Dutt sudeep.dutt@intel.com Signed-off-by: Niranjana Vishwanathapura niranjana.vishwanathapura@intel.com --- drivers/gpu/drm/i915/i915_svm_devmem.c | 72 ++++++++++++++++++++++++++ 1 file changed, 72 insertions(+)
diff --git a/drivers/gpu/drm/i915/i915_svm_devmem.c b/drivers/gpu/drm/i915/i915_svm_devmem.c index 37a205d3a82f..960b04091e44 100644 --- a/drivers/gpu/drm/i915/i915_svm_devmem.c +++ b/drivers/gpu/drm/i915/i915_svm_devmem.c @@ -142,6 +142,69 @@ i915_devmem_page_free_locked(struct drm_i915_private *dev_priv, put_page(page); }
+static int i915_migrate_cpu_copy(struct i915_devmem_migrate *migrate) +{ + const unsigned long *src = migrate->args->src; + unsigned long *dst = migrate->args->dst; + struct drm_i915_private *i915 = migrate->i915; + struct intel_memory_region *mem; + void *src_vaddr, *dst_vaddr; + u64 src_addr, dst_addr; + struct page *page; + int i, ret = 0; + + /* XXX: Copy multiple pages at a time */ + for (i = 0; !ret && i < migrate->npages; i++) { + if (!dst[i]) + continue; + + page = migrate_pfn_to_page(dst[i]); + mem = i915->mm.regions[migrate->dst_id]; + dst_addr = page_to_pfn(page); + if (migrate->dst_id != INTEL_REGION_SMEM) + dst_addr -= mem->devmem->pfn_first; + dst_addr <<= PAGE_SHIFT; + + if (migrate->dst_id == INTEL_REGION_SMEM) + dst_vaddr = phys_to_virt(dst_addr); + else + dst_vaddr = io_mapping_map_atomic_wc(&mem->iomap, + dst_addr); + if (unlikely(!dst_vaddr)) + return -ENOMEM; + + page = migrate_pfn_to_page(src[i]); + mem = i915->mm.regions[migrate->src_id]; + src_addr = page_to_pfn(page); + if (migrate->src_id != INTEL_REGION_SMEM) + src_addr -= mem->devmem->pfn_first; + src_addr <<= PAGE_SHIFT; + + if (migrate->src_id == INTEL_REGION_SMEM) + src_vaddr = phys_to_virt(src_addr); + else + src_vaddr = io_mapping_map_atomic_wc(&mem->iomap, + src_addr); + + if (likely(src_vaddr)) + memcpy(dst_vaddr, src_vaddr, PAGE_SIZE); + else + ret = -ENOMEM; + + if (migrate->dst_id != INTEL_REGION_SMEM) + io_mapping_unmap_atomic(dst_vaddr); + + if (migrate->src_id != INTEL_REGION_SMEM && src_vaddr) + io_mapping_unmap_atomic(src_vaddr); + + DRM_DEBUG_DRIVER("src [%d] 0x%llx, dst [%d] 0x%llx\n", + migrate->src_id, src_addr, + migrate->dst_id, dst_addr); + } + + return ret; +} + static int i915_devmem_migrate_alloc_and_copy(struct i915_devmem_migrate *migrate) { @@ -201,6 +264,8 @@ i915_devmem_migrate_alloc_and_copy(struct i915_devmem_migrate *migrate)
/* Copy the pages */ migrate->npages = npages; + /* XXX: Flush the caches? */ + ret = i915_migrate_cpu_copy(migrate); migrate_out: if (unlikely(ret)) { for (i = 0; i < npages; i++) { @@ -286,6 +351,7 @@ i915_devmem_fault_alloc_and_copy(struct i915_devmem_migrate *migrate) struct device *dev = migrate->i915->drm.dev; struct migrate_vma *args = migrate->args; struct page *dpage, *spage; + int err;
DRM_DEBUG_DRIVER("start 0x%lx\n", args->start); /* Allocate host page */ @@ -302,6 +368,12 @@ i915_devmem_fault_alloc_and_copy(struct i915_devmem_migrate *migrate)
/* Copy the pages */ migrate->npages = 1; + err = i915_migrate_cpu_copy(migrate); + if (unlikely(err)) { + __free_page(dpage); + args->dst[0] = 0; + return VM_FAULT_SIGBUS; + }
return 0; }