Re: [PATCH v3 13/13] mm: Remove device private pages from the physical address space

[Jordan Niethe]

Hi,

On 23/1/26 17:23, Jordan Niethe wrote:
diff --git a/drivers/gpu/drm/xe/xe_svm.c b/drivers/gpu/drm/xe/xe_svm.c
index a8aad9e0b1fb..ac3da24b2aac 100644
--- a/drivers/gpu/drm/xe/xe_svm.c
+++ b/drivers/gpu/drm/xe/xe_svm.c
@@ -452,7 +452,7 @@ static u64 xe_page_to_dpa(struct page *page)
        struct xe_pagemap *xpagemap = xe_page_to_pagemap(page);
        struct xe_vram_region *vr = xe_pagemap_to_vr(xpagemap);
        u64 hpa_base = xpagemap->hpa_base;
-       u64 pfn = page_to_pfn(page);
+       u64 pfn = device_private_page_to_offset(page);
        u64 offset;
        u64 dpa;
  
@@ -1700,8 +1700,6 @@ static void xe_pagemap_destroy_work(struct work_struct *work)
         */
        if (drm_dev_enter(drm, &idx)) {
                devm_memunmap_pages(drm->dev, pagemap);
-               devm_release_mem_region(drm->dev, pagemap->range.start,
-                                       pagemap->range.end - 
pagemap->range.start + 1);
                drm_dev_exit(idx);
        }

There's some new failures on the intel-xe CI run: 
https://patchwork.freedesktop.org/series/159738/#rev5
Looks like the issue is a missing update to call 
devm_memunmap_device_private_pagemap():

diff --git a/drivers/gpu/drm/xe/xe_svm.c b/drivers/gpu/drm/xe/xe_svm.c
index ac3da24b2aac..aadc73b6f951 100644
--- a/drivers/gpu/drm/xe/xe_svm.c
+++ b/drivers/gpu/drm/xe/xe_svm.c
@@ -1699,7 +1699,7 @@ static void xe_pagemap_destroy_work(struct work_struct 
*work)
         * will do shortly.
         */
        if (drm_dev_enter(drm, &idx)) {
-               devm_memunmap_pages(drm->dev, pagemap);
+               devm_memunmap_device_private_pagemap(drm->dev, pagemap);
                drm_dev_exit(idx);
        }
 


Thanks,
Jordan.

  
@@ -1745,8 +1743,6 @@ static struct xe_pagemap *xe_pagemap_create(struct xe_device *xe, struct xe_vram
        struct xe_pagemap *xpagemap;
        struct dev_pagemap *pagemap;
        struct drm_pagemap *dpagemap;
-       struct resource *res;
-       void *addr;
        int err;
  
  	xpagemap = kzalloc(sizeof(*xpagemap), GFP_KERNEL);
@@ -1763,36 +1759,24 @@ static struct xe_pagemap *xe_pagemap_create(struct 
xe_device *xe, struct xe_vram
        if (err)
                goto out_no_dpagemap;
  
-	res = devm_request_free_mem_region(dev, &iomem_resource,
-                                          vr->usable_size);
-       if (IS_ERR(res)) {
-               err = PTR_ERR(res);
-               goto out_err;
-       }
-
        err = drm_pagemap_acquire_owner(&xpagemap->peer, &xe_owner_list,
                                        xe_has_interconnect);
        if (err)
-               goto out_no_owner;
+               goto out_err;
  
  	pagemap->type = MEMORY_DEVICE_PRIVATE;
-       pagemap->range.start = res->start;
-       pagemap->range.end = res->end;
        pagemap->nr_range = 1;
+       pagemap->nr_pages = vr->usable_size / PAGE_SIZE;
        pagemap->owner = xpagemap->peer.owner;
        pagemap->ops = drm_pagemap_pagemap_ops_get();
-       addr = devm_memremap_pages(dev, pagemap);
-       if (IS_ERR(addr)) {
-               err = PTR_ERR(addr);
+       err = devm_memremap_device_private_pagemap(dev, pagemap);
+       if (err)
                goto out_no_pages;
-       }
-       xpagemap->hpa_base = res->start;
+       xpagemap->hpa_base = pagemap->range.start;
        return xpagemap;
  
  out_no_pages:
        drm_pagemap_release_owner(&xpagemap->peer);
-out_no_owner:
-       devm_release_mem_region(dev, res->start, res->end - res->start + 1);
  out_err:
        drm_pagemap_put(dpagemap);
        return ERR_PTR(err);
diff --git a/include/linux/hmm.h b/include/linux/hmm.h
index d8756c341620..25bb4df298f7 100644