Commit f894ddd5 authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Jason Gunthorpe
Browse files

memremap: add an owner field to struct dev_pagemap 

Add a new opaque owner field to struct dev_pagemap, which will allow the
hmm and migrate_vma code to identify who owns ZONE_DEVICE memory, and
refuse to work on mappings not owned by the calling entity.

Link: https://lore.kernel.org/r/20200316193216.920734-2-hch@lst.de


Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarRalph Campbell <rcampbell@nvidia.com>
Tested-by: default avatarBharata B Rao <bharata@linux.ibm.com>
Signed-off-by: default avatarJason Gunthorpe <jgg@mellanox.com>
parent 5a0c38d3

arch/powerpc/kvm/book3s_hv_uvmem.c

+2 −0
Original line number Diff line number Diff line
@@ -779,6 +779,8 @@ int kvmppc_uvmem_init(void) 
	kvmppc_uvmem_pgmap.type = MEMORY_DEVICE_PRIVATE;

	kvmppc_uvmem_pgmap.res = *res;

	kvmppc_uvmem_pgmap.ops = &kvmppc_uvmem_ops;

	/* just one global instance: */

	kvmppc_uvmem_pgmap.owner = &kvmppc_uvmem_pgmap;

	addr = memremap_pages(&kvmppc_uvmem_pgmap, NUMA_NO_NODE);

	if (IS_ERR(addr)) {

		ret = PTR_ERR(addr);

drivers/gpu/drm/nouveau/nouveau_dmem.c

+1 −0
Original line number Diff line number Diff line
@@ -526,6 +526,7 @@ nouveau_dmem_init(struct nouveau_drm *drm) 
	drm->dmem->pagemap.type = MEMORY_DEVICE_PRIVATE;

	drm->dmem->pagemap.res = *res;

	drm->dmem->pagemap.ops = &nouveau_dmem_pagemap_ops;

	drm->dmem->pagemap.owner = drm->dev;

	if (IS_ERR(devm_memremap_pages(device, &drm->dmem->pagemap)))

		goto out_free;

include/linux/memremap.h

+4 −0
Original line number Diff line number Diff line
@@ -103,6 +103,9 @@ struct dev_pagemap_ops { 
 * @type: memory type: see MEMORY_* in memory_hotplug.h

 * @flags: PGMAP_* flags to specify defailed behavior

 * @ops: method table

 * @owner: an opaque pointer identifying the entity that manages this

 *	instance.  Used by various helpers to make sure that no

 *	foreign ZONE_DEVICE memory is accessed.

 */

struct dev_pagemap {

	struct vmem_altmap altmap;
@@ -113,6 +116,7 @@ struct dev_pagemap { 
	enum memory_type type;

	unsigned int flags;

	const struct dev_pagemap_ops *ops;

	void *owner;

};



static inline struct vmem_altmap *pgmap_altmap(struct dev_pagemap *pgmap)

mm/memremap.c

+4 −0
Original line number Diff line number Diff line
@@ -181,6 +181,10 @@ void *memremap_pages(struct dev_pagemap *pgmap, int nid) 
			WARN(1, "Missing migrate_to_ram method\n");

			return ERR_PTR(-EINVAL);

		}

		if (!pgmap->owner) {

			WARN(1, "Missing owner\n");

			return ERR_PTR(-EINVAL);

		}

		break;

	case MEMORY_DEVICE_FS_DAX:

		if (!IS_ENABLED(CONFIG_ZONE_DEVICE) ||

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