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authorChristoph Hellwig <hch@lst.de>2019-06-26 14:27:08 +0200
committerJason Gunthorpe <jgg@mellanox.com>2019-07-02 14:32:44 -0300
commit1e240e8d4a7d92232b6214e02a0a4197a53afd6c (patch)
tree79627ced555b058e23eedd971352ee51918e5dcd /kernel
parent3ed2dcdf54d5bf1f9823b5faf1a702e7cee53982 (diff)
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memremap: move dev_pagemap callbacks into a separate structure
The dev_pagemap is a growing too many callbacks. Move them into a separate ops structure so that they are not duplicated for multiple instances, and an attacker can't easily overwrite them. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Logan Gunthorpe <logang@deltatee.com> Reviewed-by: Jason Gunthorpe <jgg@mellanox.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Tested-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Diffstat (limited to 'kernel')
-rw-r--r--kernel/memremap.c18
1 files changed, 9 insertions, 9 deletions
diff --git a/kernel/memremap.c b/kernel/memremap.c
index abda62d1e5a3..0824237ef979 100644
--- a/kernel/memremap.c
+++ b/kernel/memremap.c
@@ -92,10 +92,10 @@ static void devm_memremap_pages_release(void *data)
unsigned long pfn;
int nid;
- pgmap->kill(pgmap->ref);
+ pgmap->ops->kill(pgmap->ref);
for_each_device_pfn(pfn, pgmap)
put_page(pfn_to_page(pfn));
- pgmap->cleanup(pgmap->ref);
+ pgmap->ops->cleanup(pgmap->ref);
/* pages are dead and unused, undo the arch mapping */
align_start = res->start & ~(SECTION_SIZE - 1);
@@ -128,8 +128,8 @@ static void devm_memremap_pages_release(void *data)
* @pgmap: pointer to a struct dev_pagemap
*
* Notes:
- * 1/ At a minimum the res, ref and type members of @pgmap must be initialized
- * by the caller before passing it to this function
+ * 1/ At a minimum the res, ref and type and ops members of @pgmap must be
+ * initialized by the caller before passing it to this function
*
* 2/ The altmap field may optionally be initialized, in which case altmap_valid
* must be set to true
@@ -179,7 +179,8 @@ void *devm_memremap_pages(struct device *dev, struct dev_pagemap *pgmap)
break;
}
- if (!pgmap->ref || !pgmap->kill || !pgmap->cleanup) {
+ if (!pgmap->ref || !pgmap->ops || !pgmap->ops->kill ||
+ !pgmap->ops->cleanup) {
WARN(1, "Missing reference count teardown definition\n");
return ERR_PTR(-EINVAL);
}
@@ -293,9 +294,8 @@ void *devm_memremap_pages(struct device *dev, struct dev_pagemap *pgmap)
err_pfn_remap:
pgmap_array_delete(res);
err_array:
- pgmap->kill(pgmap->ref);
- pgmap->cleanup(pgmap->ref);
-
+ pgmap->ops->kill(pgmap->ref);
+ pgmap->ops->cleanup(pgmap->ref);
return ERR_PTR(error);
}
EXPORT_SYMBOL_GPL(devm_memremap_pages);
@@ -388,7 +388,7 @@ void __put_devmap_managed_page(struct page *page)
mem_cgroup_uncharge(page);
- page->pgmap->page_free(page, page->pgmap->data);
+ page->pgmap->ops->page_free(page, page->pgmap->data);
} else if (!count)
__put_page(page);
}