forked from mirrors/linux
		
	Device Coherent type uses device memory that is coherently accesible by the CPU. This could be shown as SP (special purpose) memory range at the BIOS-e820 memory enumeration. If no SP memory is supported in system, this could be faked by setting CONFIG_EFI_FAKE_MEMMAP. Currently, test_hmm only supports two different SP ranges of at least 256MB size. This could be specified in the kernel parameter variable efi_fake_mem. Ex. Two SP ranges of 1GB starting at 0x100000000 & 0x140000000 physical address. Ex. efi_fake_mem=1G@0x100000000:0x40000,1G@0x140000000:0x40000 Private and coherent device mirror instances can be created in the same probed. This is done by passing the module parameters spm_addr_dev0 & spm_addr_dev1. In this case, it will create four instances of device_mirror. The first two correspond to private device type, the last two to coherent type. Then, they can be easily accessed from user space through /dev/hmm_mirror<num_device>. Usually num_device 0 and 1 are for private, and 2 and 3 for coherent types. If no module parameters are passed, two instances of private type device_mirror will be created only. Link: https://lkml.kernel.org/r/20220715150521.18165-11-alex.sierra@amd.com Signed-off-by: Alex Sierra <alex.sierra@amd.com> Acked-by: Felix Kuehling <Felix.Kuehling@amd.com> Reviewed-by: Alistair Poppple <apopple@nvidia.com> Cc: Christoph Hellwig <hch@lst.de> Cc: David Hildenbrand <david@redhat.com> Cc: Jason Gunthorpe <jgg@nvidia.com> Cc: Jerome Glisse <jglisse@redhat.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Ralph Campbell <rcampbell@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
		
			
				
	
	
		
			76 lines
		
	
	
	
		
			2.8 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			76 lines
		
	
	
	
		
			2.8 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
/* 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_TO_DEV	_IOWR('H', 0x02, struct hmm_dmirror_cmd)
 | 
						|
#define HMM_DMIRROR_MIGRATE_TO_SYS	_IOWR('H', 0x03, struct hmm_dmirror_cmd)
 | 
						|
#define HMM_DMIRROR_SNAPSHOT		_IOWR('H', 0x04, struct hmm_dmirror_cmd)
 | 
						|
#define HMM_DMIRROR_EXCLUSIVE		_IOWR('H', 0x05, struct hmm_dmirror_cmd)
 | 
						|
#define HMM_DMIRROR_CHECK_EXCLUSIVE	_IOWR('H', 0x06, 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
 | 
						|
 * HMM_DMIRROR_PROT_DEV_COHERENT: Migrate device coherent page on the device
 | 
						|
 *				  the ioctl() is made
 | 
						|
 */
 | 
						|
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,
 | 
						|
	HMM_DMIRROR_PROT_DEV_COHERENT_LOCAL	= 0x40,
 | 
						|
	HMM_DMIRROR_PROT_DEV_COHERENT_REMOTE	= 0x50,
 | 
						|
};
 | 
						|
 | 
						|
enum {
 | 
						|
	/* 0 is reserved to catch uninitialized type fields */
 | 
						|
	HMM_DMIRROR_MEMORY_DEVICE_PRIVATE = 1,
 | 
						|
	HMM_DMIRROR_MEMORY_DEVICE_COHERENT,
 | 
						|
};
 | 
						|
 | 
						|
#endif /* _LIB_TEST_HMM_UAPI_H */
 |