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authorRalph Campbell <rcampbell@nvidia.com>2020-04-22 22:50:26 +0300
committerJason Gunthorpe <jgg@mellanox.com>2020-05-19 22:48:30 +0300
commitb2ef9f5a5cb37643ca5def3516c546457074b882 (patch)
tree8df33fda37b9cba9f18f4c98ea7a158b51f60259 /lib/test_hmm_uapi.h
parent2733ea144dcce789de20988c1056e228a07b1bff (diff)
downloadlinux-b2ef9f5a5cb37643ca5def3516c546457074b882.tar.xz
mm/hmm/test: add selftest driver for HMM
This driver is for testing device private memory migration and devices which use hmm_range_fault() to access system memory via device page tables. Link: https://lore.kernel.org/r/20200422195028.3684-2-rcampbell@nvidia.com Link: https://lore.kernel.org/r/20200516010424.2013-1-rcampbell@nvidia.com Signed-off-by: Ralph Campbell <rcampbell@nvidia.com> Signed-off-by: Jérôme Glisse <jglisse@redhat.com> Link: https://lore.kernel.org/r/20200509030225.14592-1-weiyongjun1@huawei.com Link: https://lore.kernel.org/r/20200509030234.14747-1-weiyongjun1@huawei.com Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com> Link: https://lore.kernel.org/r/20200511183704.GA225608@mwanda Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Diffstat (limited to 'lib/test_hmm_uapi.h')
-rw-r--r--lib/test_hmm_uapi.h59
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
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+++ 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 */