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Diffstat (limited to 'lib/test_hmm_uapi.h')
| -rw-r--r-- | lib/test_hmm_uapi.h | 59 |
1 files changed, 59 insertions, 0 deletions
diff --git a/lib/test_hmm_uapi.h b/lib/test_hmm_uapi.h new file mode 100644 index 000000000000..67b3b2e6ff5d --- /dev/null +++ b/lib/test_hmm_uapi.h @@ -0,0 +1,59 @@ +/* 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_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_ZERO = 0x10, + HMM_DMIRROR_PROT_DEV_PRIVATE_LOCAL = 0x20, + HMM_DMIRROR_PROT_DEV_PRIVATE_REMOTE = 0x30, +}; + +#endif /* _LIB_TEST_HMM_UAPI_H */ |