@@ -175,6 +175,10 @@ extern const struct vm_guest_mode_params vm_guest_mode_params[];
int open_path_or_exit(const char *path, int flags);
int open_kvm_dev_path_or_exit(void);
+
+bool get_kvm_intel_param_bool(const char *param);
+bool get_kvm_amd_param_bool(const char *param);
+
unsigned int kvm_check_cap(long cap);
static inline bool kvm_has_cap(long cap)
@@ -50,6 +50,45 @@ int open_kvm_dev_path_or_exit(void)
return _open_kvm_dev_path_or_exit(O_RDONLY);
}
+static bool get_module_param_bool(const char *module_name, const char *param)
+{
+ const int path_size = 128;
+ char path[path_size];
+ char value;
+ ssize_t r;
+ int fd;
+
+ r = snprintf(path, path_size, "/sys/module/%s/parameters/%s",
+ module_name, param);
+ TEST_ASSERT(r < path_size,
+ "Failed to construct sysfs path in %d bytes.", path_size);
+
+ fd = open_path_or_exit(path, O_RDONLY);
+
+ r = read(fd, &value, 1);
+ TEST_ASSERT(r == 1, "read(%s) failed", path);
+
+ r = close(fd);
+ TEST_ASSERT(!r, "close(%s) failed", path);
+
+ if (value == 'Y')
+ return true;
+ else if (value == 'N')
+ return false;
+
+ TEST_FAIL("Unrecognized value '%c' for boolean module param", value);
+}
+
+bool get_kvm_intel_param_bool(const char *param)
+{
+ return get_module_param_bool("kvm_intel", param);
+}
+
+bool get_kvm_amd_param_bool(const char *param)
+{
+ return get_module_param_bool("kvm_amd", param);
+}
+
/*
* Capability
*
@@ -1294,20 +1294,9 @@ unsigned long vm_compute_max_gfn(struct kvm_vm *vm)
/* Returns true if kvm_intel was loaded with unrestricted_guest=1. */
bool vm_is_unrestricted_guest(struct kvm_vm *vm)
{
- char val = 'N';
- size_t count;
- FILE *f;
-
/* Ensure that a KVM vendor-specific module is loaded. */
if (vm == NULL)
close(open_kvm_dev_path_or_exit());
- f = fopen("/sys/module/kvm_intel/parameters/unrestricted_guest", "r");
- if (f) {
- count = fread(&val, sizeof(char), 1, f);
- TEST_ASSERT(count == 1, "Unable to read from param file.");
- fclose(f);
- }
-
- return val == 'Y';
+ return get_kvm_intel_param_bool("unrestricted_guest");
}
Add helper functions for reading the value of kvm_intel and kvm_amd boolean module parameters. Use the kvm_intel variant in vm_is_unrestricted_guest() to simplify the check for kvm_intel.unrestricted_guest. No functional change intended. Signed-off-by: David Matlack <dmatlack@google.com> --- .../selftests/kvm/include/kvm_util_base.h | 4 ++ tools/testing/selftests/kvm/lib/kvm_util.c | 39 +++++++++++++++++++ .../selftests/kvm/lib/x86_64/processor.c | 13 +------ 3 files changed, 44 insertions(+), 12 deletions(-)