include/linux/memremap.h

1 /* SPDX-License-Identifier: GPL-2.0 */
8 #include <linux/percpu-refcount.h>
11 struct device;
14  * struct vmem_altmap - pre-allocated storage for vmemmap_populate
35  * Device memory that is not directly addressable by the CPU: CPU can neither
37  * backing the device memory. Doing so simplifies the implementation, but it is
45  * Device memory that is cache coherent from device and CPU point of view. This
47  * driver can hotplug the device memory using ZONE_DEVICE and with that memory
57  * fs truncate/hole punch) vs pinned pages (ex: device dma).
62  * that expose memory using a character device.
65  * Device memory residing in a PCI BAR intended for use with Peer-to-Peer
86 	 * Used for private (un-addressable) device memory only.  Must migrate
97 	 * When this is not implemented, or it returns -EOPNOTSUPP, the caller
107  * struct dev_pagemap - metadata for ZONE_DEVICE mappings
108  * @altmap: pre-allocated/reserved memory for vmemmap allocations
116  *	representation. A bigger value will set up compound struct pages
144 	return pgmap->ops && pgmap->ops->memory_failure;  in pgmap_has_memory_failure()
149 	if (pgmap->flags & PGMAP_ALTMAP_VALID)  in pgmap_altmap()
150 		return &pgmap->altmap;  in pgmap_altmap()
156 	return 1 << pgmap->vmemmap_shift;  in pgmap_vmemmap_nr()
163 		page->pgmap->type == MEMORY_DEVICE_PRIVATE;  in is_device_private_page()
168 	return is_device_private_page(&folio->page);  in folio_is_device_private()
175 		page->pgmap->type == MEMORY_DEVICE_PCI_P2PDMA;  in is_pci_p2pdma_page()
181 		page->pgmap->type == MEMORY_DEVICE_COHERENT;  in is_device_coherent_page()
186 	return is_device_coherent_page(&folio->page);  in folio_is_device_coherent()
193 void *devm_memremap_pages(struct device *dev, struct dev_pagemap *pgmap);
194 void devm_memunmap_pages(struct device *dev, struct dev_pagemap *pgmap);
201 static inline void *devm_memremap_pages(struct device *dev,  in devm_memremap_pages()
210 	return ERR_PTR(-ENXIO);  in devm_memremap_pages()
213 static inline void devm_memunmap_pages(struct device *dev,  in devm_memunmap_pages()
239 		percpu_ref_put(&pgmap->ref);  in put_dev_pagemap()