[RFC PATCH 37/39] KVM: selftests: Add helper to perform madvise by memslots

[Ackerley Tng <ackerleytng@google.com>]

A contiguous GPA range may not be contiguous in HVA.

This helper performs madvise, given a GPA range, by madvising in
blocks according to memslot configuration.

Signed-off-by: Ackerley Tng <ackerleytng@google.com>

---
 tools/include/linux/kernel.h                  |  4 +--
 .../testing/selftests/kvm/include/kvm_util.h  |  2 ++
 tools/testing/selftests/kvm/lib/kvm_util.c    | 30 +++++++++++++++++++
 3 files changed, 34 insertions(+), 2 deletions(-)

diff --git a/tools/include/linux/kernel.h b/tools/include/linux/kernel.h
index 07cfad817d53..5454cd3272ed 100644
--- a/tools/include/linux/kernel.h
+++ b/tools/include/linux/kernel.h
@@ -54,8 +54,8 @@
 	_min1 < _min2 ? _min1 : _min2; })
 #endif
 
-#define max_t(type, x, y)	max((type)x, (type)y)
-#define min_t(type, x, y)	min((type)x, (type)y)
+#define max_t(type, x, y)	max((type)(x), (type)(y))
+#define min_t(type, x, y)	min((type)(x), (type)(y))
 #define clamp(val, lo, hi)	min((typeof(val))max(val, lo), hi)
 
 #ifndef BUG_ON
diff --git a/tools/testing/selftests/kvm/include/kvm_util.h b/tools/testing/selftests/kvm/include/kvm_util.h
index 1576e7e4aefe..58b516c23574 100644
--- a/tools/testing/selftests/kvm/include/kvm_util.h
+++ b/tools/testing/selftests/kvm/include/kvm_util.h
@@ -433,6 +433,8 @@ static inline void vm_mem_set_shared(struct kvm_vm *vm, uint64_t gpa,
 void vm_guest_mem_fallocate(struct kvm_vm *vm, uint64_t gpa, uint64_t size,
 			    bool punch_hole);
 
+void vm_guest_mem_madvise(struct kvm_vm *vm, vm_paddr_t gpa_start, uint64_t size,
+			  int advice);
 static inline void vm_guest_mem_punch_hole(struct kvm_vm *vm, uint64_t gpa,
 					   uint64_t size)
 {
diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c
index 9bdd03a5da90..21ea6616124c 100644
--- a/tools/testing/selftests/kvm/lib/kvm_util.c
+++ b/tools/testing/selftests/kvm/lib/kvm_util.c
@@ -1416,6 +1416,36 @@ void vm_guest_mem_fallocate(struct kvm_vm *vm, uint64_t base, uint64_t size,
 	}
 }
 
+void vm_guest_mem_madvise(struct kvm_vm *vm, vm_paddr_t gpa_start, uint64_t size,
+			  int advice)
+{
+	size_t madvise_len;
+	vm_paddr_t gpa_end;
+	vm_paddr_t gpa;
+
+	gpa_end = gpa_start + size;
+	for (gpa = gpa_start; gpa < gpa_end; gpa += madvise_len) {
+		struct userspace_mem_region *region;
+		void *hva_start;
+		uint64_t memslot_end;
+		int ret;
+
+		region = userspace_mem_region_find(vm, gpa, gpa);
+		TEST_ASSERT(region, "Memory region not found for GPA 0x%lx", gpa);
+
+		hva_start = addr_gpa2hva(vm, gpa);
+		memslot_end = region->region.userspace_addr +
+			      region->region.memory_size;
+		madvise_len = min_t(size_t, memslot_end - (uint64_t)hva_start,
+				    gpa_end - gpa);
+
+		ret = madvise(hva_start, madvise_len, advice);
+		TEST_ASSERT(!ret, "madvise(addr=%p, len=%lx, advice=%x) failed\n",
+			    hva_start, madvise_len, advice);
+	}
+}
+
+
 /* Returns the size of a vCPU's kvm_run structure. */
 static int vcpu_mmap_sz(void)
 {
-- 
2.46.0.598.g6f2099f65c-goog