test_hmm_uapi.h

 1/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
 2/*
 3 * This is a module to test the HMM (Heterogeneous Memory Management) API
 4 * of the kernel. It allows a userspace program to expose its entire address
 5 * space through the HMM test module device file.
 6 */
 7#ifndef _LIB_TEST_HMM_UAPI_H
 8#define _LIB_TEST_HMM_UAPI_H
 9
10#include <linux/types.h>
11#include <linux/ioctl.h>
12
13/*
14 * Structure to pass to the HMM test driver to mimic a device accessing
15 * system memory and ZONE_DEVICE private memory through device page tables.
16 *
17 * @addr: (in) user address the device will read/write
18 * @ptr: (in) user address where device data is copied to/from
19 * @npages: (in) number of pages to read/write
20 * @cpages: (out) number of pages copied
21 * @faults: (out) number of device page faults seen
22 */
23struct hmm_dmirror_cmd {
24	__u64		addr;
25	__u64		ptr;
26	__u64		npages;
27	__u64		cpages;
28	__u64		faults;
29};
30
31/* Expose the address space of the calling process through hmm device file */
32#define HMM_DMIRROR_READ		_IOWR('H', 0x00, struct hmm_dmirror_cmd)
33#define HMM_DMIRROR_WRITE		_IOWR('H', 0x01, struct hmm_dmirror_cmd)
34#define HMM_DMIRROR_MIGRATE_TO_DEV	_IOWR('H', 0x02, struct hmm_dmirror_cmd)
35#define HMM_DMIRROR_MIGRATE_TO_SYS	_IOWR('H', 0x03, struct hmm_dmirror_cmd)
36#define HMM_DMIRROR_SNAPSHOT		_IOWR('H', 0x04, struct hmm_dmirror_cmd)
37#define HMM_DMIRROR_EXCLUSIVE		_IOWR('H', 0x05, struct hmm_dmirror_cmd)
38#define HMM_DMIRROR_CHECK_EXCLUSIVE	_IOWR('H', 0x06, struct hmm_dmirror_cmd)
39#define HMM_DMIRROR_RELEASE		_IOWR('H', 0x07, struct hmm_dmirror_cmd)
40#define HMM_DMIRROR_FLAGS		_IOWR('H', 0x08, struct hmm_dmirror_cmd)
41
42#define HMM_DMIRROR_FLAG_FAIL_ALLOC	(1ULL << 0)
43
44/*
45 * Values returned in hmm_dmirror_cmd.ptr for HMM_DMIRROR_SNAPSHOT.
46 * HMM_DMIRROR_PROT_ERROR: no valid mirror PTE for this page
47 * HMM_DMIRROR_PROT_NONE: unpopulated PTE or PTE with no access
48 * HMM_DMIRROR_PROT_READ: read-only PTE
49 * HMM_DMIRROR_PROT_WRITE: read/write PTE
50 * HMM_DMIRROR_PROT_PMD: PMD sized page is fully mapped by same permissions
51 * HMM_DMIRROR_PROT_PUD: PUD sized page is fully mapped by same permissions
52 * HMM_DMIRROR_PROT_ZERO: special read-only zero page
53 * HMM_DMIRROR_PROT_DEV_PRIVATE_LOCAL: Migrated device private page on the
54 *					device the ioctl() is made
55 * HMM_DMIRROR_PROT_DEV_PRIVATE_REMOTE: Migrated device private page on some
56 *					other device
57 * HMM_DMIRROR_PROT_DEV_COHERENT: Migrate device coherent page on the device
58 *				  the ioctl() is made
59 */
60enum {
61	HMM_DMIRROR_PROT_ERROR			= 0xFF,
62	HMM_DMIRROR_PROT_NONE			= 0x00,
63	HMM_DMIRROR_PROT_READ			= 0x01,
64	HMM_DMIRROR_PROT_WRITE			= 0x02,
65	HMM_DMIRROR_PROT_PMD			= 0x04,
66	HMM_DMIRROR_PROT_PUD			= 0x08,
67	HMM_DMIRROR_PROT_ZERO			= 0x10,
68	HMM_DMIRROR_PROT_DEV_PRIVATE_LOCAL	= 0x20,
69	HMM_DMIRROR_PROT_DEV_PRIVATE_REMOTE	= 0x30,
70	HMM_DMIRROR_PROT_DEV_COHERENT_LOCAL	= 0x40,
71	HMM_DMIRROR_PROT_DEV_COHERENT_REMOTE	= 0x50,
72};
73
74enum {
75	/* 0 is reserved to catch uninitialized type fields */
76	HMM_DMIRROR_MEMORY_DEVICE_PRIVATE = 1,
77	HMM_DMIRROR_MEMORY_DEVICE_COHERENT,
78};
79
80#endif /* _LIB_TEST_HMM_UAPI_H */