ASR_BASE
Change-Id: Icf3719cc0afe3eeb3edc7fa80a2eb5199ca9dda1
diff --git a/marvell/linux/tools/testing/selftests/kvm/lib/io.c b/marvell/linux/tools/testing/selftests/kvm/lib/io.c
new file mode 100644
index 0000000..eaf351c
--- /dev/null
+++ b/marvell/linux/tools/testing/selftests/kvm/lib/io.c
@@ -0,0 +1,157 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * tools/testing/selftests/kvm/lib/io.c
+ *
+ * Copyright (C) 2018, Google LLC.
+ */
+
+#include "test_util.h"
+
+/* Test Write
+ *
+ * A wrapper for write(2), that automatically handles the following
+ * special conditions:
+ *
+ * + Interrupted system call (EINTR)
+ * + Write of less than requested amount
+ * + Non-block return (EAGAIN)
+ *
+ * For each of the above, an additional write is performed to automatically
+ * continue writing the requested data.
+ * There are also many cases where write(2) can return an unexpected
+ * error (e.g. EIO). Such errors cause a TEST_ASSERT failure.
+ *
+ * Note, for function signature compatibility with write(2), this function
+ * returns the number of bytes written, but that value will always be equal
+ * to the number of requested bytes. All other conditions in this and
+ * future enhancements to this function either automatically issue another
+ * write(2) or cause a TEST_ASSERT failure.
+ *
+ * Args:
+ * fd - Opened file descriptor to file to be written.
+ * count - Number of bytes to write.
+ *
+ * Output:
+ * buf - Starting address of data to be written.
+ *
+ * Return:
+ * On success, number of bytes written.
+ * On failure, a TEST_ASSERT failure is caused.
+ */
+ssize_t test_write(int fd, const void *buf, size_t count)
+{
+ ssize_t rc;
+ ssize_t num_written = 0;
+ size_t num_left = count;
+ const char *ptr = buf;
+
+ /* Note: Count of zero is allowed (see "RETURN VALUE" portion of
+ * write(2) manpage for details.
+ */
+ TEST_ASSERT(count >= 0, "Unexpected count, count: %li", count);
+
+ do {
+ rc = write(fd, ptr, num_left);
+
+ switch (rc) {
+ case -1:
+ TEST_ASSERT(errno == EAGAIN || errno == EINTR,
+ "Unexpected write failure,\n"
+ " rc: %zi errno: %i", rc, errno);
+ continue;
+
+ case 0:
+ TEST_ASSERT(false, "Unexpected EOF,\n"
+ " rc: %zi num_written: %zi num_left: %zu",
+ rc, num_written, num_left);
+ break;
+
+ default:
+ TEST_ASSERT(rc >= 0, "Unexpected ret from write,\n"
+ " rc: %zi errno: %i", rc, errno);
+ num_written += rc;
+ num_left -= rc;
+ ptr += rc;
+ break;
+ }
+ } while (num_written < count);
+
+ return num_written;
+}
+
+/* Test Read
+ *
+ * A wrapper for read(2), that automatically handles the following
+ * special conditions:
+ *
+ * + Interrupted system call (EINTR)
+ * + Read of less than requested amount
+ * + Non-block return (EAGAIN)
+ *
+ * For each of the above, an additional read is performed to automatically
+ * continue reading the requested data.
+ * There are also many cases where read(2) can return an unexpected
+ * error (e.g. EIO). Such errors cause a TEST_ASSERT failure. Note,
+ * it is expected that the file opened by fd at the current file position
+ * contains at least the number of requested bytes to be read. A TEST_ASSERT
+ * failure is produced if an End-Of-File condition occurs, before all the
+ * data is read. It is the callers responsibility to assure that sufficient
+ * data exists.
+ *
+ * Note, for function signature compatibility with read(2), this function
+ * returns the number of bytes read, but that value will always be equal
+ * to the number of requested bytes. All other conditions in this and
+ * future enhancements to this function either automatically issue another
+ * read(2) or cause a TEST_ASSERT failure.
+ *
+ * Args:
+ * fd - Opened file descriptor to file to be read.
+ * count - Number of bytes to read.
+ *
+ * Output:
+ * buf - Starting address of where to write the bytes read.
+ *
+ * Return:
+ * On success, number of bytes read.
+ * On failure, a TEST_ASSERT failure is caused.
+ */
+ssize_t test_read(int fd, void *buf, size_t count)
+{
+ ssize_t rc;
+ ssize_t num_read = 0;
+ size_t num_left = count;
+ char *ptr = buf;
+
+ /* Note: Count of zero is allowed (see "If count is zero" portion of
+ * read(2) manpage for details.
+ */
+ TEST_ASSERT(count >= 0, "Unexpected count, count: %li", count);
+
+ do {
+ rc = read(fd, ptr, num_left);
+
+ switch (rc) {
+ case -1:
+ TEST_ASSERT(errno == EAGAIN || errno == EINTR,
+ "Unexpected read failure,\n"
+ " rc: %zi errno: %i", rc, errno);
+ break;
+
+ case 0:
+ TEST_ASSERT(false, "Unexpected EOF,\n"
+ " rc: %zi num_read: %zi num_left: %zu",
+ rc, num_read, num_left);
+ break;
+
+ default:
+ TEST_ASSERT(rc > 0, "Unexpected ret from read,\n"
+ " rc: %zi errno: %i", rc, errno);
+ num_read += rc;
+ num_left -= rc;
+ ptr += rc;
+ break;
+ }
+ } while (num_read < count);
+
+ return num_read;
+}