@@ -2237,6 +2237,17 @@ config TEST_DIV64
If unsure, say N.
+config TEST_IOV_ITER
+ tristate "Test iov_iter operation" if !KUNIT_ALL_TESTS
+ depends on KUNIT
+ default KUNIT_ALL_TESTS
+ help
+ Enable this to turn on testing of the operation of the I/O iterator
+ (iov_iter). This test is executed only once during system boot (so
+ affects only boot time), or at module load time.
+
+ If unsure, say N.
+
config KPROBES_SANITY_TEST
tristate "Kprobes sanity tests" if !KUNIT_ALL_TESTS
depends on DEBUG_KERNEL
@@ -64,6 +64,7 @@ obj-$(CONFIG_TEST_BITOPS) += test_bitops.o
CFLAGS_test_bitops.o += -Werror
obj-$(CONFIG_CPUMASK_KUNIT_TEST) += cpumask_kunit.o
obj-$(CONFIG_TEST_SYSCTL) += test_sysctl.o
+obj-$(CONFIG_TEST_IOV_ITER) += kunit_iov_iter.o
obj-$(CONFIG_HASH_KUNIT_TEST) += test_hash.o
obj-$(CONFIG_TEST_IDA) += test_ida.o
obj-$(CONFIG_TEST_UBSAN) += test_ubsan.o
new file mode 100644
@@ -0,0 +1,537 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* I/O iterator tests. This can only test kernel-backed iterator types.
+ *
+ * Copyright (C) 2023 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/module.h>
+#include <linux/vmalloc.h>
+#include <linux/mm.h>
+#include <linux/uio.h>
+#include <linux/bvec.h>
+#include <kunit/test.h>
+
+MODULE_DESCRIPTION("iov_iter testing");
+MODULE_AUTHOR("David Howells <dhowells@redhat.com>");
+MODULE_LICENSE("GPL");
+
+struct kvec_test_range {
+ int from, to;
+};
+
+static const struct kvec_test_range kvec_test_ranges[] = {
+ { 0x00002, 0x00002 },
+ { 0x00027, 0x03000 },
+ { 0x05193, 0x18794 },
+ { 0x20000, 0x20000 },
+ { 0x20000, 0x24000 },
+ { 0x24000, 0x27001 },
+ { 0x29000, 0xffffb },
+ { 0xffffd, 0xffffe },
+ { -1 }
+};
+
+static inline u8 pattern(unsigned long x)
+{
+ return x & 0xff;
+}
+
+static void iov_kunit_unmap(void *data)
+{
+ vunmap(data);
+}
+
+static void *__init iov_kunit_create_buffer(struct kunit *test,
+ struct page ***ppages,
+ size_t npages)
+{
+ struct page **pages;
+ unsigned long got;
+ void *buffer;
+
+ pages = kunit_kcalloc(test, npages, sizeof(struct page *), GFP_KERNEL);
+ KUNIT_ASSERT_NOT_ERR_OR_NULL(test, pages);
+ *ppages = pages;
+
+ got = alloc_pages_bulk_array(GFP_KERNEL, npages, pages);
+ if (got != npages) {
+ release_pages(pages, got);
+ KUNIT_ASSERT_EQ(test, got, npages);
+ }
+
+ buffer = vmap(pages, npages, VM_MAP | VM_MAP_PUT_PAGES, PAGE_KERNEL);
+ KUNIT_ASSERT_NOT_ERR_OR_NULL(test, buffer);
+
+ kunit_add_action_or_reset(test, iov_kunit_unmap, buffer);
+ return buffer;
+}
+
+static void __init iov_kunit_load_kvec(struct kunit *test,
+ struct iov_iter *iter, int dir,
+ struct kvec *kvec, unsigned int kvmax,
+ void *buffer, size_t bufsize,
+ const struct kvec_test_range *pr)
+{
+ size_t size = 0;
+ int i;
+
+ for (i = 0; i < kvmax; i++, pr++) {
+ if (pr->from < 0)
+ break;
+ KUNIT_ASSERT_GE(test, pr->to, pr->from);
+ KUNIT_ASSERT_LE(test, pr->to, bufsize);
+ kvec[i].iov_base = buffer + pr->from;
+ kvec[i].iov_len = pr->to - pr->from;
+ size += pr->to - pr->from;
+ }
+ KUNIT_ASSERT_LE(test, size, bufsize);
+
+ iov_iter_kvec(iter, dir, kvec, i, size);
+}
+
+/*
+ * Test copying to a ITER_KVEC-type iterator.
+ */
+static void __init iov_kunit_copy_to_kvec(struct kunit *test)
+{
+ const struct kvec_test_range *pr;
+ struct iov_iter iter;
+ struct page **spages, **bpages;
+ struct kvec kvec[8];
+ u8 *scratch, *buffer;
+ size_t bufsize, npages, size, copied;
+ int i, patt;
+
+ bufsize = 0x100000;
+ npages = bufsize / PAGE_SIZE;
+
+ scratch = iov_kunit_create_buffer(test, &spages, npages);
+ for (i = 0; i < bufsize; i++)
+ scratch[i] = pattern(i);
+
+ buffer = iov_kunit_create_buffer(test, &bpages, npages);
+ memset(buffer, 0, bufsize);
+
+ iov_kunit_load_kvec(test, &iter, READ, kvec, ARRAY_SIZE(kvec),
+ buffer, bufsize, kvec_test_ranges);
+ size = iter.count;
+
+ copied = copy_to_iter(scratch, size, &iter);
+
+ KUNIT_EXPECT_EQ(test, copied, size);
+ KUNIT_EXPECT_EQ(test, iter.count, 0);
+ KUNIT_EXPECT_EQ(test, iter.nr_segs, 0);
+
+ /* Build the expected image in the scratch buffer. */
+ patt = 0;
+ memset(scratch, 0, bufsize);
+ for (pr = kvec_test_ranges; pr->from >= 0; pr++)
+ for (i = pr->from; i < pr->to; i++)
+ scratch[i] = pattern(patt++);
+
+ /* Compare the images */
+ for (i = 0; i < bufsize; i++) {
+ KUNIT_EXPECT_EQ_MSG(test, buffer[i], scratch[i], "at i=%x", i);
+ if (buffer[i] != scratch[i])
+ return;
+ }
+
+ KUNIT_SUCCEED();
+}
+
+/*
+ * Test copying from a ITER_KVEC-type iterator.
+ */
+static void __init iov_kunit_copy_from_kvec(struct kunit *test)
+{
+ const struct kvec_test_range *pr;
+ struct iov_iter iter;
+ struct page **spages, **bpages;
+ struct kvec kvec[8];
+ u8 *scratch, *buffer;
+ size_t bufsize, npages, size, copied;
+ int i, j;
+
+ bufsize = 0x100000;
+ npages = bufsize / PAGE_SIZE;
+
+ buffer = iov_kunit_create_buffer(test, &bpages, npages);
+ for (i = 0; i < bufsize; i++)
+ buffer[i] = pattern(i);
+
+ scratch = iov_kunit_create_buffer(test, &spages, npages);
+ memset(scratch, 0, bufsize);
+
+ iov_kunit_load_kvec(test, &iter, WRITE, kvec, ARRAY_SIZE(kvec),
+ buffer, bufsize, kvec_test_ranges);
+ size = min(iter.count, bufsize);
+
+ copied = copy_from_iter(scratch, size, &iter);
+
+ KUNIT_EXPECT_EQ(test, copied, size);
+ KUNIT_EXPECT_EQ(test, iter.count, 0);
+ KUNIT_EXPECT_EQ(test, iter.nr_segs, 0);
+
+ /* Build the expected image in the main buffer. */
+ i = 0;
+ memset(buffer, 0, bufsize);
+ for (pr = kvec_test_ranges; pr->from >= 0; pr++) {
+ for (j = pr->from; j < pr->to; j++) {
+ buffer[i++] = pattern(j);
+ if (i >= bufsize)
+ goto stop;
+ }
+ }
+stop:
+
+ /* Compare the images */
+ for (i = 0; i < bufsize; i++) {
+ KUNIT_EXPECT_EQ_MSG(test, scratch[i], buffer[i], "at i=%x", i);
+ if (scratch[i] != buffer[i])
+ return;
+ }
+
+ KUNIT_SUCCEED();
+}
+
+struct bvec_test_range {
+ int page, from, to;
+};
+
+static const struct bvec_test_range bvec_test_ranges[] = {
+ { 0, 0x0002, 0x0002 },
+ { 1, 0x0027, 0x0893 },
+ { 2, 0x0193, 0x0794 },
+ { 3, 0x0000, 0x1000 },
+ { 4, 0x0000, 0x1000 },
+ { 5, 0x0000, 0x1000 },
+ { 6, 0x0000, 0x0ffb },
+ { 6, 0x0ffd, 0x0ffe },
+ { -1, -1, -1 }
+};
+
+static void __init iov_kunit_load_bvec(struct kunit *test,
+ struct iov_iter *iter, int dir,
+ struct bio_vec *bvec, unsigned int bvmax,
+ struct page **pages, size_t npages,
+ size_t bufsize,
+ const struct bvec_test_range *pr)
+{
+ struct page *can_merge = NULL, *page;
+ size_t size = 0;
+ int i;
+
+ for (i = 0; i < bvmax; i++, pr++) {
+ if (pr->from < 0)
+ break;
+ KUNIT_ASSERT_LT(test, pr->page, npages);
+ KUNIT_ASSERT_LT(test, pr->page * PAGE_SIZE, bufsize);
+ KUNIT_ASSERT_GE(test, pr->from, 0);
+ KUNIT_ASSERT_GE(test, pr->to, pr->from);
+ KUNIT_ASSERT_LE(test, pr->to, PAGE_SIZE);
+
+ page = pages[pr->page];
+ if (pr->from == 0 && pr->from != pr->to && page == can_merge) {
+ i--;
+ bvec[i].bv_len += pr->to;
+ } else {
+ bvec_set_page(&bvec[i], page, pr->to - pr->from, pr->from);
+ }
+
+ size += pr->to - pr->from;
+ if ((pr->to & ~PAGE_MASK) == 0)
+ can_merge = page + pr->to / PAGE_SIZE;
+ else
+ can_merge = NULL;
+ }
+
+ iov_iter_bvec(iter, dir, bvec, i, size);
+}
+
+/*
+ * Test copying to a ITER_BVEC-type iterator.
+ */
+static void __init iov_kunit_copy_to_bvec(struct kunit *test)
+{
+ const struct bvec_test_range *pr;
+ struct iov_iter iter;
+ struct bio_vec bvec[8];
+ struct page **spages, **bpages;
+ u8 *scratch, *buffer;
+ size_t bufsize, npages, size, copied;
+ int i, b, patt;
+
+ bufsize = 0x100000;
+ npages = bufsize / PAGE_SIZE;
+
+ scratch = iov_kunit_create_buffer(test, &spages, npages);
+ for (i = 0; i < bufsize; i++)
+ scratch[i] = pattern(i);
+
+ buffer = iov_kunit_create_buffer(test, &bpages, npages);
+ memset(buffer, 0, bufsize);
+
+ iov_kunit_load_bvec(test, &iter, READ, bvec, ARRAY_SIZE(bvec),
+ bpages, npages, bufsize, bvec_test_ranges);
+ size = iter.count;
+
+ copied = copy_to_iter(scratch, size, &iter);
+
+ KUNIT_EXPECT_EQ(test, copied, size);
+ KUNIT_EXPECT_EQ(test, iter.count, 0);
+ KUNIT_EXPECT_EQ(test, iter.nr_segs, 0);
+
+ /* Build the expected image in the scratch buffer. */
+ b = 0;
+ patt = 0;
+ memset(scratch, 0, bufsize);
+ for (pr = bvec_test_ranges; pr->from >= 0; pr++, b++) {
+ u8 *p = scratch + pr->page * PAGE_SIZE;
+
+ for (i = pr->from; i < pr->to; i++)
+ p[i] = pattern(patt++);
+ }
+
+ /* Compare the images */
+ for (i = 0; i < bufsize; i++) {
+ KUNIT_EXPECT_EQ_MSG(test, buffer[i], scratch[i], "at i=%x", i);
+ if (buffer[i] != scratch[i])
+ return;
+ }
+
+ KUNIT_SUCCEED();
+}
+
+/*
+ * Test copying from a ITER_BVEC-type iterator.
+ */
+static void __init iov_kunit_copy_from_bvec(struct kunit *test)
+{
+ const struct bvec_test_range *pr;
+ struct iov_iter iter;
+ struct bio_vec bvec[8];
+ struct page **spages, **bpages;
+ u8 *scratch, *buffer;
+ size_t bufsize, npages, size, copied;
+ int i, j;
+
+ bufsize = 0x100000;
+ npages = bufsize / PAGE_SIZE;
+
+ buffer = iov_kunit_create_buffer(test, &bpages, npages);
+ for (i = 0; i < bufsize; i++)
+ buffer[i] = pattern(i);
+
+ scratch = iov_kunit_create_buffer(test, &spages, npages);
+ memset(scratch, 0, bufsize);
+
+ iov_kunit_load_bvec(test, &iter, WRITE, bvec, ARRAY_SIZE(bvec),
+ bpages, npages, bufsize, bvec_test_ranges);
+ size = iter.count;
+
+ copied = copy_from_iter(scratch, size, &iter);
+
+ KUNIT_EXPECT_EQ(test, copied, size);
+ KUNIT_EXPECT_EQ(test, iter.count, 0);
+ KUNIT_EXPECT_EQ(test, iter.nr_segs, 0);
+
+ /* Build the expected image in the main buffer. */
+ i = 0;
+ memset(buffer, 0, bufsize);
+ for (pr = bvec_test_ranges; pr->from >= 0; pr++) {
+ size_t patt = pr->page * PAGE_SIZE;
+
+ for (j = pr->from; j < pr->to; j++) {
+ buffer[i++] = pattern(patt + j);
+ if (i >= bufsize)
+ goto stop;
+ }
+ }
+stop:
+
+ /* Compare the images */
+ for (i = 0; i < bufsize; i++) {
+ KUNIT_EXPECT_EQ_MSG(test, scratch[i], buffer[i], "at i=%x", i);
+ if (scratch[i] != buffer[i])
+ return;
+ }
+
+ KUNIT_SUCCEED();
+}
+
+static void iov_kunit_destroy_xarray(void *data)
+{
+ struct xarray *xarray = data;
+
+ xa_destroy(xarray);
+ kfree(xarray);
+}
+
+static void __init iov_kunit_load_xarray(struct kunit *test,
+ struct iov_iter *iter, int dir,
+ struct xarray *xarray,
+ struct page **pages, size_t npages)
+{
+ size_t size = 0;
+ int i;
+
+ for (i = 0; i < npages; i++) {
+ void *x = xa_store(xarray, i, pages[i], GFP_KERNEL);
+
+ KUNIT_ASSERT_FALSE(test, xa_is_err(x));
+ size += PAGE_SIZE;
+ }
+ iov_iter_xarray(iter, dir, xarray, 0, size);
+}
+
+static struct xarray *iov_kunit_create_xarray(struct kunit *test)
+{
+ struct xarray *xarray;
+
+ xarray = kzalloc(sizeof(struct xarray), GFP_KERNEL);
+ xa_init(xarray);
+ KUNIT_ASSERT_NOT_ERR_OR_NULL(test, xarray);
+ kunit_add_action_or_reset(test, iov_kunit_destroy_xarray, xarray);
+ return xarray;
+}
+
+/*
+ * Test copying to a ITER_XARRAY-type iterator.
+ */
+static void __init iov_kunit_copy_to_xarray(struct kunit *test)
+{
+ const struct kvec_test_range *pr;
+ struct iov_iter iter;
+ struct xarray *xarray;
+ struct page **spages, **bpages;
+ u8 *scratch, *buffer;
+ size_t bufsize, npages, size, copied;
+ int i, patt;
+
+ bufsize = 0x100000;
+ npages = bufsize / PAGE_SIZE;
+
+ xarray = iov_kunit_create_xarray(test);
+
+ scratch = iov_kunit_create_buffer(test, &spages, npages);
+ for (i = 0; i < bufsize; i++)
+ scratch[i] = pattern(i);
+
+ buffer = iov_kunit_create_buffer(test, &bpages, npages);
+ memset(buffer, 0, bufsize);
+
+ iov_kunit_load_xarray(test, &iter, READ, xarray, bpages, npages);
+
+ i = 0;
+ for (pr = kvec_test_ranges; pr->from >= 0; pr++) {
+ size = pr->to - pr->from;
+ KUNIT_ASSERT_LE(test, pr->to, bufsize);
+
+ iov_iter_xarray(&iter, READ, xarray, pr->from, size);
+ copied = copy_to_iter(scratch + i, size, &iter);
+
+ KUNIT_EXPECT_EQ(test, copied, size);
+ KUNIT_EXPECT_EQ(test, iter.count, 0);
+ KUNIT_EXPECT_EQ(test, iter.iov_offset, size);
+ i += size;
+ }
+
+ /* Build the expected image in the scratch buffer. */
+ patt = 0;
+ memset(scratch, 0, bufsize);
+ for (pr = kvec_test_ranges; pr->from >= 0; pr++)
+ for (i = pr->from; i < pr->to; i++)
+ scratch[i] = pattern(patt++);
+
+ /* Compare the images */
+ for (i = 0; i < bufsize; i++) {
+ KUNIT_EXPECT_EQ_MSG(test, buffer[i], scratch[i], "at i=%x", i);
+ if (buffer[i] != scratch[i])
+ return;
+ }
+
+ KUNIT_SUCCEED();
+}
+
+/*
+ * Test copying from a ITER_XARRAY-type iterator.
+ */
+static void __init iov_kunit_copy_from_xarray(struct kunit *test)
+{
+ const struct kvec_test_range *pr;
+ struct iov_iter iter;
+ struct xarray *xarray;
+ struct page **spages, **bpages;
+ u8 *scratch, *buffer;
+ size_t bufsize, npages, size, copied;
+ int i, j;
+
+ bufsize = 0x100000;
+ npages = bufsize / PAGE_SIZE;
+
+ xarray = iov_kunit_create_xarray(test);
+
+ buffer = iov_kunit_create_buffer(test, &bpages, npages);
+ for (i = 0; i < bufsize; i++)
+ buffer[i] = pattern(i);
+
+ scratch = iov_kunit_create_buffer(test, &spages, npages);
+ memset(scratch, 0, bufsize);
+
+ iov_kunit_load_xarray(test, &iter, READ, xarray, bpages, npages);
+
+ i = 0;
+ for (pr = kvec_test_ranges; pr->from >= 0; pr++) {
+ size = pr->to - pr->from;
+ KUNIT_ASSERT_LE(test, pr->to, bufsize);
+
+ iov_iter_xarray(&iter, WRITE, xarray, pr->from, size);
+ copied = copy_from_iter(scratch + i, size, &iter);
+
+ KUNIT_EXPECT_EQ(test, copied, size);
+ KUNIT_EXPECT_EQ(test, iter.count, 0);
+ KUNIT_EXPECT_EQ(test, iter.iov_offset, size);
+ i += size;
+ }
+
+ /* Build the expected image in the main buffer. */
+ i = 0;
+ memset(buffer, 0, bufsize);
+ for (pr = kvec_test_ranges; pr->from >= 0; pr++) {
+ for (j = pr->from; j < pr->to; j++) {
+ buffer[i++] = pattern(j);
+ if (i >= bufsize)
+ goto stop;
+ }
+ }
+stop:
+
+ /* Compare the images */
+ for (i = 0; i < bufsize; i++) {
+ KUNIT_EXPECT_EQ_MSG(test, scratch[i], buffer[i], "at i=%x", i);
+ if (scratch[i] != buffer[i])
+ return;
+ }
+
+ KUNIT_SUCCEED();
+}
+
+static struct kunit_case __refdata iov_kunit_cases[] = {
+ KUNIT_CASE(iov_kunit_copy_to_kvec),
+ KUNIT_CASE(iov_kunit_copy_from_kvec),
+ KUNIT_CASE(iov_kunit_copy_to_bvec),
+ KUNIT_CASE(iov_kunit_copy_from_bvec),
+ KUNIT_CASE(iov_kunit_copy_to_xarray),
+ KUNIT_CASE(iov_kunit_copy_from_xarray),
+ {}
+};
+
+static struct kunit_suite iov_kunit_suite = {
+ .name = "iov_iter",
+ .test_cases = iov_kunit_cases,
+};
+
+kunit_test_suites(&iov_kunit_suite);
Add some kunit tests for page extraction for ITER_BVEC, ITER_KVEC and ITER_XARRAY type iterators. ITER_UBUF and ITER_IOVEC aren't dealt with as they require userspace VM interaction. ITER_DISCARD isn't dealt with either as that does nothing. Signed-off-by: David Howells <dhowells@redhat.com> cc: Christoph Hellwig <hch@lst.de> cc: Christian Brauner <brauner@kernel.org> cc: Jens Axboe <axboe@kernel.dk> cc: Al Viro <viro@zeniv.linux.org.uk> cc: David Hildenbrand <david@redhat.com> cc: John Hubbard <jhubbard@nvidia.com> cc: linux-mm@kvack.org cc: linux-block@vger.kernel.org cc: linux-fsdevel@vger.kernel.org --- lib/Kconfig.debug | 11 + lib/Makefile | 1 + lib/kunit_iov_iter.c | 537 +++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 549 insertions(+) create mode 100644 lib/kunit_iov_iter.c