Merge branches 'work.misc' and 'work.dcache' of git://git.kernel.org/pub/scm/linux...

[sfrench/cifs-2.6.git] / kernel / memremap.c

diff --git a/kernel/memremap.c b/kernel/memremap.c
index 5857267a4af5dab0cb0eb85ed9b61cdfcbc57dcc..38283363da06d40057ddfe71c3c8ec1a2c7a94d2 100644 (file)
--- a/kernel/memremap.c
+++ b/kernel/memremap.c
@@ -176,10 +176,27 @@ void *devm_memremap_pages(struct device *dev, struct dev_pagemap *pgmap)
        unsigned long pfn, pgoff, order;
        pgprot_t pgprot = PAGE_KERNEL;
        int error, nid, is_ram;
+       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);
 
@@ -199,7 +216,6 @@ void *devm_memremap_pages(struct device *dev, struct dev_pagemap *pgmap)
 
        mutex_lock(&pgmap_lock);
        error = 0;
-       align_end = align_start + align_size - 1;
 
        foreach_order_pgoff(res, order, pgoff) {
                error = __radix_tree_insert(&pgmap_radix,
@@ -305,7 +321,7 @@ EXPORT_SYMBOL_GPL(get_dev_pagemap);
 
 #ifdef CONFIG_DEV_PAGEMAP_OPS
 DEFINE_STATIC_KEY_FALSE(devmap_managed_key);
-EXPORT_SYMBOL_GPL(devmap_managed_key);
+EXPORT_SYMBOL(devmap_managed_key);
 static atomic_t devmap_enable;
 
 /*
@@ -346,5 +362,5 @@ void __put_devmap_managed_page(struct page *page)
        } else if (!count)
                __put_page(page);
 }
-EXPORT_SYMBOL_GPL(__put_devmap_managed_page);
+EXPORT_SYMBOL(__put_devmap_managed_page);
 #endif /* CONFIG_DEV_PAGEMAP_OPS */