BACKPORT: fs: kernfs: add poll file operation
[GitHub/LineageOS/android_kernel_motorola_exynos9610.git] / kernel / memremap.c
index 403ab9cdb949a0483bd82c811a3383eed77e5246..0d676d6d2f6259638c1f8ddd15f63e5739f2f5b3 100644 (file)
@@ -248,13 +248,16 @@ int device_private_entry_fault(struct vm_area_struct *vma,
 EXPORT_SYMBOL(device_private_entry_fault);
 #endif /* CONFIG_DEVICE_PRIVATE */
 
-static void pgmap_radix_release(struct resource *res)
+static void pgmap_radix_release(struct resource *res, unsigned long end_pgoff)
 {
        unsigned long pgoff, order;
 
        mutex_lock(&pgmap_lock);
-       foreach_order_pgoff(res, order, pgoff)
+       foreach_order_pgoff(res, order, pgoff) {
+               if (pgoff >= end_pgoff)
+                       break;
                radix_tree_delete(&pgmap_radix, PHYS_PFN(res->start) + pgoff);
+       }
        mutex_unlock(&pgmap_lock);
 
        synchronize_rcu();
@@ -301,14 +304,15 @@ static void devm_memremap_pages_release(struct device *dev, void *data)
 
        /* pages are dead and unused, undo the arch mapping */
        align_start = res->start & ~(SECTION_SIZE - 1);
-       align_size = ALIGN(resource_size(res), SECTION_SIZE);
+       align_size = ALIGN(res->start + resource_size(res), SECTION_SIZE)
+               - align_start;
 
        mem_hotplug_begin();
        arch_remove_memory(align_start, align_size);
        mem_hotplug_done();
 
        untrack_pfn(NULL, PHYS_PFN(align_start), align_size);
-       pgmap_radix_release(res);
+       pgmap_radix_release(res, -1);
        dev_WARN_ONCE(dev, pgmap->altmap && pgmap->altmap->alloc,
                        "%s: failed to free all reserved pages\n", __func__);
 }
@@ -351,22 +355,36 @@ void *devm_memremap_pages(struct device *dev, struct resource *res,
        struct dev_pagemap *pgmap;
        struct page_map *page_map;
        int error, nid, is_ram, i = 0;
+       struct dev_pagemap *conflict_pgmap;
 
        align_start = res->start & ~(SECTION_SIZE - 1);
        align_size = ALIGN(res->start + resource_size(res), SECTION_SIZE)
                - align_start;
+       align_end = align_start + align_size - 1;
+
+       conflict_pgmap = get_dev_pagemap(PHYS_PFN(align_start), NULL);
+       if (conflict_pgmap) {
+               dev_WARN(dev, "Conflicting mapping in same section\n");
+               put_dev_pagemap(conflict_pgmap);
+               return ERR_PTR(-ENOMEM);
+       }
+
+       conflict_pgmap = get_dev_pagemap(PHYS_PFN(align_end), NULL);
+       if (conflict_pgmap) {
+               dev_WARN(dev, "Conflicting mapping in same section\n");
+               put_dev_pagemap(conflict_pgmap);
+               return ERR_PTR(-ENOMEM);
+       }
+
        is_ram = region_intersects(align_start, align_size,
                IORESOURCE_SYSTEM_RAM, IORES_DESC_NONE);
 
-       if (is_ram == REGION_MIXED) {
-               WARN_ONCE(1, "%s attempted on mixed region %pr\n",
-                               __func__, res);
+       if (is_ram != REGION_DISJOINT) {
+               WARN_ONCE(1, "%s attempted on %s region %pr\n", __func__,
+                               is_ram == REGION_MIXED ? "mixed" : "ram", res);
                return ERR_PTR(-ENXIO);
        }
 
-       if (is_ram == REGION_INTERSECTS)
-               return __va(res->start);
-
        if (!ref)
                return ERR_PTR(-EINVAL);
 
@@ -392,7 +410,6 @@ void *devm_memremap_pages(struct device *dev, struct resource *res,
 
        mutex_lock(&pgmap_lock);
        error = 0;
-       align_end = align_start + align_size - 1;
 
        foreach_order_pgoff(res, order, pgoff) {
                struct dev_pagemap *dup;
@@ -458,11 +475,11 @@ void *devm_memremap_pages(struct device *dev, struct resource *res,
        untrack_pfn(NULL, PHYS_PFN(align_start), align_size);
  err_pfn_remap:
  err_radix:
-       pgmap_radix_release(res);
+       pgmap_radix_release(res, pgoff);
        devres_free(page_map);
        return ERR_PTR(error);
 }
-EXPORT_SYMBOL(devm_memremap_pages);
+EXPORT_SYMBOL_GPL(devm_memremap_pages);
 
 unsigned long vmem_altmap_offset(struct vmem_altmap *altmap)
 {