From: Sean Christopherson <seanjc@xxxxxxxxxx>
Refactor align() to work with non-pointers and split into separate
helpers for aligning up vs. down. Add align_ptr_up() for use with
pointers. Expose all helpers so that they can be used by tests and/or
other utilities. The align_down() helper in particular will be used to
ensure gpa alignment for hugepages.
No functional change intended.
Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
[Added sepearate up/down helpers and replaced open-coded alignment
bit math throughout the KVM selftests.]
Signed-off-by: David Matlack <dmatlack@xxxxxxxxxx>
---
tools/testing/selftests/kvm/dirty_log_test.c | 6 ++---
.../testing/selftests/kvm/include/test_util.h | 25 +++++++++++++++++++
.../selftests/kvm/kvm_page_table_test.c | 2 +-
tools/testing/selftests/kvm/lib/elf.c | 3 +--
tools/testing/selftests/kvm/lib/kvm_util.c | 13 ++--------
.../selftests/kvm/lib/perf_test_util.c | 4 +--
6 files changed, 34 insertions(+), 19 deletions(-)
diff --git a/tools/testing/selftests/kvm/dirty_log_test.c b/tools/testing/selftests/kvm/dirty_log_test.c
index 792c60e1b17d..3fcd89e195c7 100644
--- a/tools/testing/selftests/kvm/dirty_log_test.c
+++ b/tools/testing/selftests/kvm/dirty_log_test.c
@@ -115,7 +115,7 @@ static void guest_code(void)
addr = guest_test_virt_mem;
addr += (READ_ONCE(random_array[i]) % guest_num_pages)
* guest_page_size;
- addr &= ~(host_page_size - 1);
+ addr = align_down(addr, host_page_size);
*(uint64_t *)addr = READ_ONCE(iteration);
}
@@ -737,14 +737,14 @@ static void run_test(enum vm_guest_mode mode, void *arg)
if (!p->phys_offset) {
guest_test_phys_mem = (vm_get_max_gfn(vm) -
guest_num_pages) * guest_page_size;
- guest_test_phys_mem &= ~(host_page_size - 1);
+ guest_test_phys_mem = align_down(guest_test_phys_mem, host_page_size);
} else {
guest_test_phys_mem = p->phys_offset;
}
#ifdef __s390x__
/* Align to 1M (segment size) */
- guest_test_phys_mem &= ~((1 << 20) - 1);
+ guest_test_phys_mem = align_down(guest_test_phys_mem, 1 << 20);
#endif
pr_info("guest physical test memory offset: 0x%lx\n", guest_test_phys_mem);
diff --git a/tools/testing/selftests/kvm/include/test_util.h b/tools/testing/selftests/kvm/include/test_util.h
index f8fddc84c0d3..78c06310cc0e 100644
--- a/tools/testing/selftests/kvm/include/test_util.h
+++ b/tools/testing/selftests/kvm/include/test_util.h
@@ -117,4 +117,29 @@ static inline bool backing_src_is_shared(enum vm_mem_backing_src_type t)
return vm_mem_backing_src_alias(t)->flag & MAP_SHARED;
}
+/* Aligns x up to the next multiple of size. Size must be a power of 2. */
+static inline uint64_t align_up(uint64_t x, uint64_t size)
+{
+ uint64_t mask = size - 1;
+
+ TEST_ASSERT(size != 0 && !(size & (size - 1)),
+ "size not a power of 2: %lu", size);
+ return ((x + mask) & ~mask);
+}
+
+static inline uint64_t align_down(uint64_t x, uint64_t size)
+{
+ uint64_t x_aligned_up = align_up(x, size);
+
+ if (x == x_aligned_up)
+ return x;
+ else
+ return x_aligned_up - size;
+}
+
+static inline void *align_ptr_up(void *x, size_t size)
+{
+ return (void *)align_up((unsigned long)x, size);
+}
+
#endif /* SELFTEST_KVM_TEST_UTIL_H */
diff --git a/tools/testing/selftests/kvm/kvm_page_table_test.c b/tools/testing/selftests/kvm/kvm_page_table_test.c
index 36407cb0ec85..3836322add00 100644
--- a/tools/testing/selftests/kvm/kvm_page_table_test.c
+++ b/tools/testing/selftests/kvm/kvm_page_table_test.c
@@ -280,7 +280,7 @@ static struct kvm_vm *pre_init_before_test(enum vm_guest_mode mode, void *arg)
#ifdef __s390x__
alignment = max(0x100000, alignment);
#endif
- guest_test_phys_mem &= ~(alignment - 1);
+ guest_test_phys_mem = align_down(guest_test_virt_mem, alignment);
/* Set up the shared data structure test_args */
test_args.vm = vm;
diff --git a/tools/testing/selftests/kvm/lib/elf.c b/tools/testing/selftests/kvm/lib/elf.c
index eac44f5d0db0..13e8e3dcf984 100644
--- a/tools/testing/selftests/kvm/lib/elf.c
+++ b/tools/testing/selftests/kvm/lib/elf.c
@@ -157,8 +157,7 @@ void kvm_vm_elf_load(struct kvm_vm *vm, const char *filename)
"memsize of 0,\n"
" phdr index: %u p_memsz: 0x%" PRIx64,
n1, (uint64_t) phdr.p_memsz);
- vm_vaddr_t seg_vstart = phdr.p_vaddr;
- seg_vstart &= ~(vm_vaddr_t)(vm->page_size - 1);
+ vm_vaddr_t seg_vstart = align_down(phdr.p_vaddr, vm->page_size);
vm_vaddr_t seg_vend = phdr.p_vaddr + phdr.p_memsz - 1;
seg_vend |= vm->page_size - 1;
size_t seg_size = seg_vend - seg_vstart + 1;
diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c
index b624c24290dd..63375118d48f 100644
--- a/tools/testing/selftests/kvm/lib/kvm_util.c
+++ b/tools/testing/selftests/kvm/lib/kvm_util.c
@@ -22,15 +22,6 @@
static int vcpu_mmap_sz(void);
-/* Aligns x up to the next multiple of size. Size must be a power of 2. */
-static void *align(void *x, size_t size)
-{
- size_t mask = size - 1;
- TEST_ASSERT(size != 0 && !(size & (size - 1)),
- "size not a power of 2: %lu", size);
- return (void *) (((size_t) x + mask) & ~mask);
-}
-
/*
* Open KVM_DEV_PATH if available, otherwise exit the entire program.
*
@@ -911,7 +902,7 @@ void vm_userspace_mem_region_add(struct kvm_vm *vm,
region->mmap_start, errno);
/* Align host address */
- region->host_mem = align(region->mmap_start, alignment);
+ region->host_mem = align_ptr_up(region->mmap_start, alignment);
/* As needed perform madvise */
if ((src_type == VM_MEM_SRC_ANONYMOUS ||
@@ -954,7 +945,7 @@ void vm_userspace_mem_region_add(struct kvm_vm *vm,
"mmap of alias failed, errno: %i", errno);
/* Align host alias address */
- region->host_alias = align(region->mmap_alias, alignment);
+ region->host_alias = align_ptr_up(region->mmap_alias, alignment);
}
}
diff --git a/tools/testing/selftests/kvm/lib/perf_test_util.c b/tools/testing/selftests/kvm/lib/perf_test_util.c
index 0ef80dbdc116..6b8d5020dc54 100644
--- a/tools/testing/selftests/kvm/lib/perf_test_util.c
+++ b/tools/testing/selftests/kvm/lib/perf_test_util.c
@@ -92,10 +92,10 @@ struct kvm_vm *perf_test_create_vm(enum vm_guest_mode mode, int vcpus,
guest_test_phys_mem = (vm_get_max_gfn(vm) - guest_num_pages) *
perf_test_args.guest_page_size;
- guest_test_phys_mem &= ~(perf_test_args.host_page_size - 1);
+ guest_test_phys_mem = align_down(guest_test_phys_mem, perf_test_args.host_page_size);
#ifdef __s390x__
/* Align to 1M (segment size) */
- guest_test_phys_mem &= ~((1 << 20) - 1);
+ guest_test_phys_mem = align_down(guest_test_phys_mem, 1 << 20);
#endif
pr_info("guest physical test memory offset: 0x%lx\n", guest_test_phys_mem);
--
2.34.0.rc1.387.gb447b232ab-goog
