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 */ 23 struct 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 _IOWR('H', 0x02, struct hmm_dmirror_cmd) 35 #define HMM_DMIRROR_SNAPSHOT _IOWR('H', 0x03, struct hmm_dmirror_cmd) 36 37 /* 38 * Values returned in hmm_dmirror_cmd.ptr for HMM_DMIRROR_SNAPSHOT. 39 * HMM_DMIRROR_PROT_ERROR: no valid mirror PTE for this page 40 * HMM_DMIRROR_PROT_NONE: unpopulated PTE or PTE with no access 41 * HMM_DMIRROR_PROT_READ: read-only PTE 42 * HMM_DMIRROR_PROT_WRITE: read/write PTE 43 * HMM_DMIRROR_PROT_ZERO: special read-only zero page 44 * HMM_DMIRROR_PROT_DEV_PRIVATE_LOCAL: Migrated device private page on the 45 * device the ioctl() is made 46 * HMM_DMIRROR_PROT_DEV_PRIVATE_REMOTE: Migrated device private page on some 47 * other device 48 */ 49 enum { 50 HMM_DMIRROR_PROT_ERROR = 0xFF, 51 HMM_DMIRROR_PROT_NONE = 0x00, 52 HMM_DMIRROR_PROT_READ = 0x01, 53 HMM_DMIRROR_PROT_WRITE = 0x02, 54 HMM_DMIRROR_PROT_ZERO = 0x10, 55 HMM_DMIRROR_PROT_DEV_PRIVATE_LOCAL = 0x20, 56 HMM_DMIRROR_PROT_DEV_PRIVATE_REMOTE = 0x30, 57 }; 58 59 #endif /* _LIB_TEST_HMM_UAPI_H */ 60