// SPDX-License-Identifier: GPL-2.0-only/* * kvm_binary_stats_test * * Copyright (C) 2021, Google LLC. * * Test the fd-based interface for KVM statistics. */#include <fcntl.h>#include <stdio.h>#include <stdlib.h>#include <string.h>#include <errno.h> #include "test_util.h" #include "kvm_util.h"#include "asm/kvm.h"#include "linux/kvm.h"#include "kselftest.h" static void stats_test(int stats_fd){	ssize_t ret;	int i;	size_t size_desc;	size_t size_data = 0;	struct kvm_stats_header header;	char *id;	struct kvm_stats_desc *stats_desc;	u64 *stats_data;	struct kvm_stats_desc *pdesc;	u32 type, unit, base; 	/* Read kvm stats header */	read_stats_header(stats_fd, &header); 	size_desc = get_stats_descriptor_size(&header); 	/* Read kvm stats id string */	id = malloc(header.name_size);	TEST_ASSERT(id, "Allocate memory for id string"); 	ret = pread(stats_fd, id, header.name_size, sizeof(header));	TEST_ASSERT(ret == header.name_size,		    "Expected header size '%u', read '%lu' bytes",		    header.name_size, ret); 	/* Check id string, that should start with "kvm" */	TEST_ASSERT(!strncmp(id, "kvm", 3) && strlen(id) < header.name_size,		    "Invalid KVM stats type, id: %s", id); 	/* Sanity check for other fields in header */	if (header.num_desc == 0) {		ksft_print_msg("No KVM stats defined!\n");		return;	}	/*	 * The descriptor and data offsets must be valid, they must not overlap	 * the header, and the descriptor and data blocks must not overlap each	 * other.  Note, the data block is rechecked after its size is known.	 */	TEST_ASSERT(header.desc_offset && header.desc_offset >= sizeof(header) &&		    header.data_offset && header.data_offset >= sizeof(header),		    "Invalid offset fields in header"); 	TEST_ASSERT(header.desc_offset > header.data_offset ||		    (header.desc_offset + size_desc * header.num_desc <= header.data_offset),		    "Descriptor block is overlapped with data block"); 	/* Read kvm stats descriptors */	stats_desc = read_stats_descriptors(stats_fd, &header); 	/* Sanity check for fields in descriptors */	for (i = 0; i < header.num_desc; ++i) {		pdesc = get_stats_descriptor(stats_desc, i, &header);		type = pdesc->flags & KVM_STATS_TYPE_MASK;		unit = pdesc->flags & KVM_STATS_UNIT_MASK;		base = pdesc->flags & KVM_STATS_BASE_MASK; 		/* Check name string */		TEST_ASSERT(strlen(pdesc->name) < header.name_size,			    "KVM stats name (index: %d) too long", i); 		/* Check type,unit,base boundaries */		TEST_ASSERT(type <= KVM_STATS_TYPE_MAX,			    "Unknown KVM stats (%s) type: %u", pdesc->name, type);		TEST_ASSERT(unit <= KVM_STATS_UNIT_MAX,			    "Unknown KVM stats (%s) unit: %u", pdesc->name, unit);		TEST_ASSERT(base <= KVM_STATS_BASE_MAX,			    "Unknown KVM stats (%s) base: %u", pdesc->name, base); 		/*		 * Check exponent for stats unit		 * Exponent for counter should be greater than or equal to 0		 * Exponent for unit bytes should be greater than or equal to 0		 * Exponent for unit seconds should be less than or equal to 0		 * Exponent for unit clock cycles should be greater than or		 * equal to 0		 * Exponent for unit boolean should be 0		 */		switch (pdesc->flags & KVM_STATS_UNIT_MASK) {		case KVM_STATS_UNIT_NONE:		case KVM_STATS_UNIT_BYTES:		case KVM_STATS_UNIT_CYCLES:			TEST_ASSERT(pdesc->exponent >= 0,				    "Unsupported KVM stats (%s) exponent: %i",				    pdesc->name, pdesc->exponent);			break;		case KVM_STATS_UNIT_SECONDS:			TEST_ASSERT(pdesc->exponent <= 0,				    "Unsupported KVM stats (%s) exponent: %i",				    pdesc->name, pdesc->exponent);			break;		case KVM_STATS_UNIT_BOOLEAN:			TEST_ASSERT(pdesc->exponent == 0,				    "Unsupported KVM stats (%s) exponent: %d",				    pdesc->name, pdesc->exponent);			break;		} 		/* Check size field, which should not be zero */		TEST_ASSERT(pdesc->size,			    "KVM descriptor(%s) with size of 0", pdesc->name);		/* Check bucket_size field */		switch (pdesc->flags & KVM_STATS_TYPE_MASK) {		case KVM_STATS_TYPE_LINEAR_HIST:			TEST_ASSERT(pdesc->bucket_size,				    "Bucket size of Linear Histogram stats (%s) is zero",				    pdesc->name);			break;		default:			TEST_ASSERT(!pdesc->bucket_size,				    "Bucket size of stats (%s) is not zero",				    pdesc->name);		}		size_data = max(size_data, pdesc->offset + pdesc->size * sizeof(*stats_data));	} 	/*	 * Now that the size of the data block is known, verify the data block	 * doesn't overlap the descriptor block.	 */	TEST_ASSERT(header.data_offset >= header.desc_offset ||		    header.data_offset + size_data <= header.desc_offset,		    "Data block is overlapped with Descriptor block"); 	/* Check validity of all stats data size */	TEST_ASSERT(size_data >= header.num_desc * sizeof(*stats_data),		    "Data size is not correct"); 	/* Allocate memory for stats data */	stats_data = malloc(size_data);	TEST_ASSERT(stats_data, "Allocate memory for stats data");	/* Read kvm stats data as a bulk */	ret = pread(stats_fd, stats_data, size_data, header.data_offset);	TEST_ASSERT(ret == size_data, "Read KVM stats data");	/* Read kvm stats data one by one */	for (i = 0; i < header.num_desc; ++i) {		pdesc = get_stats_descriptor(stats_desc, i, &header);		read_stat_data(stats_fd, &header, pdesc, stats_data,			       pdesc->size);	} 	free(stats_data);	free(stats_desc);	free(id); 	close(stats_fd);	TEST_ASSERT(fcntl(stats_fd, F_GETFD) == -1, "Stats fd not freed");} #define DEFAULT_NUM_VM		4#define DEFAULT_NUM_VCPU	4 /* * Usage: kvm_bin_form_stats [#vm] [#vcpu] * The first parameter #vm set the number of VMs being created. * The second parameter #vcpu set the number of VCPUs being created. * By default, DEFAULT_NUM_VM VM and DEFAULT_NUM_VCPU VCPU for the VM would be * created for testing. */ int main(int argc, char *argv[]){	int vm_stats_fds, *vcpu_stats_fds;	int i, j;	struct kvm_vcpu **vcpus;	struct kvm_vm **vms;	int max_vm = DEFAULT_NUM_VM;	int max_vcpu = DEFAULT_NUM_VCPU; 	/* Get the number of VMs and VCPUs that would be created for testing. */	if (argc > 1) {		max_vm = strtol(argv[1], NULL, 0);		if (max_vm <= 0)			max_vm = DEFAULT_NUM_VM;	}	if (argc > 2) {		max_vcpu = strtol(argv[2], NULL, 0);		if (max_vcpu <= 0)			max_vcpu = DEFAULT_NUM_VCPU;	} 	ksft_print_header(); 	/* Check the extension for binary stats */	TEST_REQUIRE(kvm_has_cap(KVM_CAP_BINARY_STATS_FD)); 	ksft_set_plan(max_vm); 	/* Create VMs and VCPUs */	vms = malloc(sizeof(vms[0]) * max_vm);	TEST_ASSERT(vms, "Allocate memory for storing VM pointers"); 	vcpus = malloc(sizeof(struct kvm_vcpu *) * max_vm * max_vcpu);	TEST_ASSERT(vcpus, "Allocate memory for storing vCPU pointers"); 	/*	 * Not per-VM as the array is populated, used, and invalidated within a	 * single for-loop iteration.	 */	vcpu_stats_fds = calloc(max_vm, sizeof(*vcpu_stats_fds));	TEST_ASSERT(vcpu_stats_fds, "Allocate memory for VM stats fds"); 	for (i = 0; i < max_vm; ++i) {		vms[i] = vm_create_barebones();		for (j = 0; j < max_vcpu; ++j)			vcpus[i * max_vcpu + j] = __vm_vcpu_add(vms[i], j);	} 	/*	 * Check stats read for every VM and vCPU, with a variety of flavors.	 * Note, stats_test() closes the passed in stats fd.	 */	for (i = 0; i < max_vm; ++i) {		/*		 * Verify that creating multiple userspace references to a		 * single stats file works and doesn't cause explosions.		 */		vm_stats_fds = vm_get_stats_fd(vms[i]);		stats_test(kvm_dup(vm_stats_fds)); 		/* Verify userspace can instantiate multiple stats files. */		stats_test(vm_get_stats_fd(vms[i])); 		for (j = 0; j < max_vcpu; ++j) {			vcpu_stats_fds[j] = vcpu_get_stats_fd(vcpus[i * max_vcpu + j]);			stats_test(kvm_dup(vcpu_stats_fds[j]));			stats_test(vcpu_get_stats_fd(vcpus[i * max_vcpu + j]));		} 		/*		 * Close the VM fd and redo the stats tests.  KVM should gift a		 * reference (to the VM) to each stats fd, i.e. stats should		 * still be accessible even after userspace has put its last		 * _direct_ reference to the VM.		 */		kvm_vm_free(vms[i]); 		stats_test(vm_stats_fds);		for (j = 0; j < max_vcpu; ++j)			stats_test(vcpu_stats_fds[j]); 		ksft_test_result_pass("vm%i\n", i);	} 	free(vms);	free(vcpus);	free(vcpu_stats_fds); 	ksft_finished();	/* Print results and exit() accordingly */}