https://github.com/torvalds/linux
Tip revision: 62fb9874f5da54fdb243003b386128037319b219 authored by Linus Torvalds on 27 June 2021, 22:21:11 UTC
Linux 5.13
Linux 5.13
Tip revision: 62fb987
test_hmm_uapi.h
/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
/*
* This is a module to test the HMM (Heterogeneous Memory Management) API
* of the kernel. It allows a userspace program to expose its entire address
* space through the HMM test module device file.
*/
#ifndef _LIB_TEST_HMM_UAPI_H
#define _LIB_TEST_HMM_UAPI_H
#include <linux/types.h>
#include <linux/ioctl.h>
/*
* Structure to pass to the HMM test driver to mimic a device accessing
* system memory and ZONE_DEVICE private memory through device page tables.
*
* @addr: (in) user address the device will read/write
* @ptr: (in) user address where device data is copied to/from
* @npages: (in) number of pages to read/write
* @cpages: (out) number of pages copied
* @faults: (out) number of device page faults seen
*/
struct hmm_dmirror_cmd {
__u64 addr;
__u64 ptr;
__u64 npages;
__u64 cpages;
__u64 faults;
};
/* Expose the address space of the calling process through hmm device file */
#define HMM_DMIRROR_READ _IOWR('H', 0x00, struct hmm_dmirror_cmd)
#define HMM_DMIRROR_WRITE _IOWR('H', 0x01, struct hmm_dmirror_cmd)
#define HMM_DMIRROR_MIGRATE _IOWR('H', 0x02, struct hmm_dmirror_cmd)
#define HMM_DMIRROR_SNAPSHOT _IOWR('H', 0x03, struct hmm_dmirror_cmd)
/*
* Values returned in hmm_dmirror_cmd.ptr for HMM_DMIRROR_SNAPSHOT.
* HMM_DMIRROR_PROT_ERROR: no valid mirror PTE for this page
* HMM_DMIRROR_PROT_NONE: unpopulated PTE or PTE with no access
* HMM_DMIRROR_PROT_READ: read-only PTE
* HMM_DMIRROR_PROT_WRITE: read/write PTE
* HMM_DMIRROR_PROT_PMD: PMD sized page is fully mapped by same permissions
* HMM_DMIRROR_PROT_PUD: PUD sized page is fully mapped by same permissions
* HMM_DMIRROR_PROT_ZERO: special read-only zero page
* HMM_DMIRROR_PROT_DEV_PRIVATE_LOCAL: Migrated device private page on the
* device the ioctl() is made
* HMM_DMIRROR_PROT_DEV_PRIVATE_REMOTE: Migrated device private page on some
* other device
*/
enum {
HMM_DMIRROR_PROT_ERROR = 0xFF,
HMM_DMIRROR_PROT_NONE = 0x00,
HMM_DMIRROR_PROT_READ = 0x01,
HMM_DMIRROR_PROT_WRITE = 0x02,
HMM_DMIRROR_PROT_PMD = 0x04,
HMM_DMIRROR_PROT_PUD = 0x08,
HMM_DMIRROR_PROT_ZERO = 0x10,
HMM_DMIRROR_PROT_DEV_PRIVATE_LOCAL = 0x20,
HMM_DMIRROR_PROT_DEV_PRIVATE_REMOTE = 0x30,
};
#endif /* _LIB_TEST_HMM_UAPI_H */