1 files changed, 62 insertions, 0 deletions
diff --git a/tools/testing/selftests/mm/vm_util.c b/tools/testing/selftests/mm/vm_util.c
index a36734fb62f3..61d7bf1f8c62 100644
--- a/tools/testing/selftests/mm/vm_util.c
+++ b/tools/testing/selftests/mm/vm_util.c
@@ -1,5 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0
 #include <string.h>
+#include <errno.h>
 #include <fcntl.h>
 #include <dirent.h>
 #include <inttypes.h>
@@ -424,3 +425,64 @@ bool check_vmflag_io(void *addr)
 		flags += flaglen;
 	}
 }
+
+/*
+ * Open an fd at /proc/$pid/maps and configure procmap_out ready for
+ * PROCMAP_QUERY query. Returns 0 on success, or an error code otherwise.
+ */
+int open_procmap(pid_t pid, struct procmap_fd *procmap_out)
+{
+	char path[256];
+	int ret = 0;
+
+	memset(procmap_out, '\0', sizeof(*procmap_out));
+	sprintf(path, "/proc/%d/maps", pid);
+	procmap_out->query.size = sizeof(procmap_out->query);
+	procmap_out->fd = open(path, O_RDONLY);
+	if (procmap_out->fd < 0)
+		ret = -errno;
+
+	return ret;
+}
+
+/* Perform PROCMAP_QUERY. Returns 0 on success, or an error code otherwise. */
+int query_procmap(struct procmap_fd *procmap)
+{
+	int ret = 0;
+
+	if (ioctl(procmap->fd, PROCMAP_QUERY, &procmap->query) == -1)
+		ret = -errno;
+
+	return ret;
+}
+
+/*
+ * Try to find the VMA at specified address, returns true if found, false if not
+ * found, and the test is failed if any other error occurs.
+ *
+ * On success, procmap->query is populated with the results.
+ */
+bool find_vma_procmap(struct procmap_fd *procmap, void *address)
+{
+	int err;
+
+	procmap->query.query_flags = 0;
+	procmap->query.query_addr = (unsigned long)address;
+	err = query_procmap(procmap);
+	if (!err)
+		return true;
+
+	if (err != -ENOENT)
+		ksft_exit_fail_msg("%s: Error %d on ioctl(PROCMAP_QUERY)\n",
+				   __func__, err);
+	return false;
+}
+
+/*
+ * Close fd used by PROCMAP_QUERY mechanism. Returns 0 on success, or an error
+ * code otherwise.
+ */
+int close_procmap(struct procmap_fd *procmap)
+{
+	return close(procmap->fd);
+}