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>
This commit is contained in:
Christoph Hellwig
2019-06-26 14:27:08 +02:00
committed by Jason Gunthorpe
parent 3ed2dcdf54
commit 1e240e8d4a
8 changed files with 65 additions and 46 deletions

View File

@@ -1384,6 +1384,12 @@ static void hmm_devmem_free(struct page *page, void *data)
devmem->ops->free(devmem, page);
}
static const struct dev_pagemap_ops hmm_pagemap_ops = {
.page_free = hmm_devmem_free,
.kill = hmm_devmem_ref_kill,
.cleanup = hmm_devmem_ref_exit,
};
/*
* hmm_devmem_add() - hotplug ZONE_DEVICE memory for device memory
*
@@ -1438,12 +1444,10 @@ struct hmm_devmem *hmm_devmem_add(const struct hmm_devmem_ops *ops,
devmem->pagemap.type = MEMORY_DEVICE_PRIVATE;
devmem->pagemap.res = *devmem->resource;
devmem->pagemap.page_free = hmm_devmem_free;
devmem->pagemap.ops = &hmm_pagemap_ops;
devmem->pagemap.altmap_valid = false;
devmem->pagemap.ref = &devmem->ref;
devmem->pagemap.data = devmem;
devmem->pagemap.kill = hmm_devmem_ref_kill;
devmem->pagemap.cleanup = hmm_devmem_ref_exit;
result = devm_memremap_pages(devmem->device, &devmem->pagemap);
if (IS_ERR(result))