Merge branch kvm-arm64/selftest/s2-faults into kvmarm-master/next

* kvm-arm64/selftest/s2-faults:
  : .
  : New KVM/arm64 selftests exercising various sorts of S2 faults, courtesy
  : of Ricardo Koller. From the cover letter:
  :
  : "This series adds a new aarch64 selftest for testing stage 2 fault handling
  : for various combinations of guest accesses (e.g., write, S1PTW), backing
  : sources (e.g., anon), and types of faults (e.g., read on hugetlbfs with a
  : hole, write on a readonly memslot). Each test tries a different combination
  : and then checks that the access results in the right behavior (e.g., uffd
  : faults with the right address and write/read flag). [...]"
  : .
  KVM: selftests: aarch64: Add mix of tests into page_fault_test
  KVM: selftests: aarch64: Add readonly memslot tests into page_fault_test
  KVM: selftests: aarch64: Add dirty logging tests into page_fault_test
  KVM: selftests: aarch64: Add userfaultfd tests into page_fault_test
  KVM: selftests: aarch64: Add aarch64/page_fault_test
  KVM: selftests: Use the right memslot for code, page-tables, and data allocations
  KVM: selftests: Fix alignment in virt_arch_pgd_alloc() and vm_vaddr_alloc()
  KVM: selftests: Add vm->memslots[] and enum kvm_mem_region_type
  KVM: selftests: Stash backing_src_type in struct userspace_mem_region
  tools: Copy bitfield.h from the kernel sources
  KVM: selftests: aarch64: Construct DEFAULT_MAIR_EL1 using sysreg.h macros
  KVM: selftests: Add missing close and munmap in __vm_mem_region_delete()
  KVM: selftests: aarch64: Add virt_get_pte_hva() library function
  KVM: selftests: Add a userfaultfd library

Signed-off-by: Marc Zyngier <[email protected]>

tools/include/linux/bitfield.h

@@ -0,0 +1,176 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2014 Felix Fietkau <[email protected]>
+ * Copyright (C) 2004 - 2009 Ivo van Doorn <[email protected]>
+ */
+
+#ifndef _LINUX_BITFIELD_H
+#define _LINUX_BITFIELD_H
+
+#include <linux/build_bug.h>
+#include <asm/byteorder.h>
+
+/*
+ * Bitfield access macros
+ *
+ * FIELD_{GET,PREP} macros take as first parameter shifted mask
+ * from which they extract the base mask and shift amount.
+ * Mask must be a compilation time constant.
+ *
+ * Example:
+ *
+ *  #define REG_FIELD_A  GENMASK(6, 0)
+ *  #define REG_FIELD_B  BIT(7)
+ *  #define REG_FIELD_C  GENMASK(15, 8)
+ *  #define REG_FIELD_D  GENMASK(31, 16)
+ *
+ * Get:
+ *  a = FIELD_GET(REG_FIELD_A, reg);
+ *  b = FIELD_GET(REG_FIELD_B, reg);
+ *
+ * Set:
+ *  reg = FIELD_PREP(REG_FIELD_A, 1) |
+ *	  FIELD_PREP(REG_FIELD_B, 0) |
+ *	  FIELD_PREP(REG_FIELD_C, c) |
+ *	  FIELD_PREP(REG_FIELD_D, 0x40);
+ *
+ * Modify:
+ *  reg &= ~REG_FIELD_C;
+ *  reg |= FIELD_PREP(REG_FIELD_C, c);
+ */
+
+#define __bf_shf(x) (__builtin_ffsll(x) - 1)
+
+#define __scalar_type_to_unsigned_cases(type)				\
+		unsigned type:	(unsigned type)0,			\
+		signed type:	(unsigned type)0
+
+#define __unsigned_scalar_typeof(x) typeof(				\
+		_Generic((x),						\
+			char:	(unsigned char)0,			\
+			__scalar_type_to_unsigned_cases(char),		\
+			__scalar_type_to_unsigned_cases(short),		\
+			__scalar_type_to_unsigned_cases(int),		\
+			__scalar_type_to_unsigned_cases(long),		\
+			__scalar_type_to_unsigned_cases(long long),	\
+			default: (x)))
+
+#define __bf_cast_unsigned(type, x)	((__unsigned_scalar_typeof(type))(x))
+
+#define __BF_FIELD_CHECK(_mask, _reg, _val, _pfx)			\
+	({								\
+		BUILD_BUG_ON_MSG(!__builtin_constant_p(_mask),		\
+				 _pfx "mask is not constant");		\
+		BUILD_BUG_ON_MSG((_mask) == 0, _pfx "mask is zero");	\
+		BUILD_BUG_ON_MSG(__builtin_constant_p(_val) ?		\
+				 ~((_mask) >> __bf_shf(_mask)) & (_val) : 0, \
+				 _pfx "value too large for the field"); \
+		BUILD_BUG_ON_MSG(__bf_cast_unsigned(_mask, _mask) >	\
+				 __bf_cast_unsigned(_reg, ~0ull),	\
+				 _pfx "type of reg too small for mask"); \
+		__BUILD_BUG_ON_NOT_POWER_OF_2((_mask) +			\
+					      (1ULL << __bf_shf(_mask))); \
+	})
+
+/**
+ * FIELD_MAX() - produce the maximum value representable by a field
+ * @_mask: shifted mask defining the field's length and position
+ *
+ * FIELD_MAX() returns the maximum value that can be held in the field
+ * specified by @_mask.
+ */
+#define FIELD_MAX(_mask)						\
+	({								\
+		__BF_FIELD_CHECK(_mask, 0ULL, 0ULL, "FIELD_MAX: ");	\
+		(typeof(_mask))((_mask) >> __bf_shf(_mask));		\
+	})
+
+/**
+ * FIELD_FIT() - check if value fits in the field
+ * @_mask: shifted mask defining the field's length and position
+ * @_val:  value to test against the field
+ *
+ * Return: true if @_val can fit inside @_mask, false if @_val is too big.
+ */
+#define FIELD_FIT(_mask, _val)						\
+	({								\
+		__BF_FIELD_CHECK(_mask, 0ULL, 0ULL, "FIELD_FIT: ");	\
+		!((((typeof(_mask))_val) << __bf_shf(_mask)) & ~(_mask)); \
+	})
+
+/**
+ * FIELD_PREP() - prepare a bitfield element
+ * @_mask: shifted mask defining the field's length and position
+ * @_val:  value to put in the field
+ *
+ * FIELD_PREP() masks and shifts up the value.  The result should
+ * be combined with other fields of the bitfield using logical OR.
+ */
+#define FIELD_PREP(_mask, _val)						\
+	({								\
+		__BF_FIELD_CHECK(_mask, 0ULL, _val, "FIELD_PREP: ");	\
+		((typeof(_mask))(_val) << __bf_shf(_mask)) & (_mask);	\
+	})
+
+/**
+ * FIELD_GET() - extract a bitfield element
+ * @_mask: shifted mask defining the field's length and position
+ * @_reg:  value of entire bitfield
+ *
+ * FIELD_GET() extracts the field specified by @_mask from the
+ * bitfield passed in as @_reg by masking and shifting it down.
+ */
+#define FIELD_GET(_mask, _reg)						\
+	({								\
+		__BF_FIELD_CHECK(_mask, _reg, 0U, "FIELD_GET: ");	\
+		(typeof(_mask))(((_reg) & (_mask)) >> __bf_shf(_mask));	\
+	})
+
+extern void __compiletime_error("value doesn't fit into mask")
+__field_overflow(void);
+extern void __compiletime_error("bad bitfield mask")
+__bad_mask(void);
+static __always_inline u64 field_multiplier(u64 field)
+{
+	if ((field | (field - 1)) & ((field | (field - 1)) + 1))
+		__bad_mask();
+	return field & -field;
+}
+static __always_inline u64 field_mask(u64 field)
+{
+	return field / field_multiplier(field);
+}
+#define field_max(field)	((typeof(field))field_mask(field))
+#define ____MAKE_OP(type,base,to,from)					\
+static __always_inline __##type type##_encode_bits(base v, base field)	\
+{									\
+	if (__builtin_constant_p(v) && (v & ~field_mask(field)))	\
+		__field_overflow();					\
+	return to((v & field_mask(field)) * field_multiplier(field));	\
+}									\
+static __always_inline __##type type##_replace_bits(__##type old,	\
+					base val, base field)		\
+{									\
+	return (old & ~to(field)) | type##_encode_bits(val, field);	\
+}									\
+static __always_inline void type##p_replace_bits(__##type *p,		\
+					base val, base field)		\
+{									\
+	*p = (*p & ~to(field)) | type##_encode_bits(val, field);	\
+}									\
+static __always_inline base type##_get_bits(__##type v, base field)	\
+{									\
+	return (from(v) & field)/field_multiplier(field);		\
+}
+#define __MAKE_OP(size)							\
+	____MAKE_OP(le##size,u##size,cpu_to_le##size,le##size##_to_cpu)	\
+	____MAKE_OP(be##size,u##size,cpu_to_be##size,be##size##_to_cpu)	\
+	____MAKE_OP(u##size,u##size,,)
+____MAKE_OP(u8,u8,,)
+__MAKE_OP(16)
+__MAKE_OP(32)
+__MAKE_OP(64)
+#undef __MAKE_OP
+#undef ____MAKE_OP
+
+#endif

tools/testing/selftests/kvm/.gitignore

@@ -4,6 +4,7 @@
 /aarch64/debug-exceptions
 /aarch64/get-reg-list
 /aarch64/hypercalls
+/aarch64/page_fault_test
 /aarch64/psci_test
 /aarch64/vcpu_width_config
 /aarch64/vgic_init

tools/testing/selftests/kvm/Makefile

@@ -47,6 +47,7 @@ LIBKVM += lib/perf_test_util.c
 LIBKVM += lib/rbtree.c
 LIBKVM += lib/sparsebit.c
 LIBKVM += lib/test_util.c
+LIBKVM += lib/userfaultfd_util.c
 
 LIBKVM_STRING += lib/string_override.c
 
@@ -152,6 +153,7 @@ TEST_GEN_PROGS_aarch64 += aarch64/arch_timer
 TEST_GEN_PROGS_aarch64 += aarch64/debug-exceptions
 TEST_GEN_PROGS_aarch64 += aarch64/get-reg-list
 TEST_GEN_PROGS_aarch64 += aarch64/hypercalls
+TEST_GEN_PROGS_aarch64 += aarch64/page_fault_test
 TEST_GEN_PROGS_aarch64 += aarch64/psci_test
 TEST_GEN_PROGS_aarch64 += aarch64/vcpu_width_config
 TEST_GEN_PROGS_aarch64 += aarch64/vgic_init