[PATCH v3 02/10] iov_iter: Consolidate some of the repeated code into helpers

David Howells
2023-09-22T11:30:57Z

Consolidate some of the repeated code snippets into helper functions to
reduce the line count.

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: Brendan Higgins <brendanhiggins@google.com>
cc: David Gow <davidgow@google.com>
cc: linux-kselftest@vger.kernel.org
cc: kunit-dev@googlegroups.com
cc: linux-mm@kvack.org
cc: linux-fsdevel@vger.kernel.org
---
lib/kunit_iov_iter.c | 189 +++++++++++++++++++------------------------
1 file changed, 84 insertions(+), 105 deletions(-)

diff --git a/lib/kunit_iov_iter.c b/lib/kunit_iov_iter.c
index 4a6c0efd33f5..ee586eb652b4 100644
--- a/lib/kunit_iov_iter.c
+++ b/lib/kunit_iov_iter.c
@@ -19,18 +19,18 @@ MODULE_AUTHOR("David Howells <dhowells@redhat.com>");
MODULE_LICENSE("GPL");

struct kvec_test_range {
- int from, to;
+ int page, 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 },
+ { 0, 0x00002, 0x00002 },
+ { 0, 0x00027, 0x03000 },
+ { 0, 0x05193, 0x18794 },
+ { 0, 0x20000, 0x20000 },
+ { 0, 0x20000, 0x24000 },
+ { 0, 0x24000, 0x27001 },
+ { 0, 0x29000, 0xffffb },
+ { 0, 0xffffd, 0xffffe },
{ -1 }
};

@@ -69,6 +69,57 @@ static void *__init iov_kunit_create_buffer(struct kunit *test,
return buffer;
}

+/*
+ * Build the reference pattern in the scratch buffer that we expect to see in
+ * the iterator buffer (ie. the result of copy *to*).
+ */
+static void iov_kunit_build_to_reference_pattern(struct kunit *test, u8 *scratch,
+ size_t bufsize,
+ const struct kvec_test_range *pr)
+{
+ int i, patt = 0;
+
+ memset(scratch, 0, bufsize);
+ for (; pr->page >= 0; pr++)
+ for (i = pr->from; i < pr->to; i++)
+ scratch[i] = pattern(patt++);
+}
+
+/*
+ * Build the reference pattern in the iterator buffer that we expect to see in
+ * the scratch buffer (ie. the result of copy *from*).
+ */
+static void iov_kunit_build_from_reference_pattern(struct kunit *test, u8 *buffer,
+ size_t bufsize,
+ const struct kvec_test_range *pr)
+{
+ size_t i = 0, j;
+
+ memset(buffer, 0, bufsize);
+ for (; pr->page >= 0; pr++) {
+ for (j = pr->from; j < pr->to; j++) {
+ buffer[i++] = pattern(j);
+ if (i >= bufsize)
+ return;
+ }
+ }
+}
+
+/*
+ * Compare two kernel buffers to see that they're the same.
+ */
+static void iov_kunit_check_pattern(struct kunit *test, const u8 *buffer,
+ const u8 *scratch, size_t bufsize)
+{
+ size_t i;
+
+ 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;
+ }
+}
+
static void __init iov_kunit_load_kvec(struct kunit *test,
struct iov_iter *iter, int dir,
struct kvec *kvec, unsigned int kvmax,
@@ -79,7 +130,7 @@ static void __init iov_kunit_load_kvec(struct kunit *test,
int i;

for (i = 0; i < kvmax; i++, pr++) {
- if (pr->from < 0)
+ if (pr->page < 0)
break;
KUNIT_ASSERT_GE(test, pr->to, pr->from);
KUNIT_ASSERT_LE(test, pr->to, bufsize);
@@ -97,13 +148,12 @@ static void __init iov_kunit_load_kvec(struct kunit *test,
*/
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;
+ int i;

bufsize = 0x100000;
npages = bufsize / PAGE_SIZE;
@@ -125,20 +175,8 @@ static void __init iov_kunit_copy_to_kvec(struct kunit *test)
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;
- }
-
+ iov_kunit_build_to_reference_pattern(test, scratch, bufsize, kvec_test_ranges);
+ iov_kunit_check_pattern(test, buffer, scratch, bufsize);
KUNIT_SUCCEED();
}

@@ -147,13 +185,12 @@ static void __init iov_kunit_copy_to_kvec(struct kunit *test)
*/
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;
+ int i;

bufsize = 0x100000;
npages = bufsize / PAGE_SIZE;
@@ -175,25 +212,8 @@ static void __init iov_kunit_copy_from_kvec(struct kunit *test)
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;
- }
-
+ iov_kunit_build_from_reference_pattern(test, buffer, bufsize, kvec_test_ranges);
+ iov_kunit_check_pattern(test, buffer, scratch, bufsize);
KUNIT_SUCCEED();
}

@@ -210,7 +230,7 @@ static const struct bvec_test_range bvec_test_ranges[] = {
{ 5, 0x0000, 0x1000 },
{ 6, 0x0000, 0x0ffb },
{ 6, 0x0ffd, 0x0ffe },
- { -1, -1, -1 }
+ { -1 }
};

static void __init iov_kunit_load_bvec(struct kunit *test,
@@ -225,7 +245,7 @@ static void __init iov_kunit_load_bvec(struct kunit *test,
int i;

for (i = 0; i < bvmax; i++, pr++) {
- if (pr->from < 0)
+ if (pr->page < 0)
break;
KUNIT_ASSERT_LT(test, pr->page, npages);
KUNIT_ASSERT_LT(test, pr->page * PAGE_SIZE, bufsize);
@@ -288,20 +308,14 @@ static void __init iov_kunit_copy_to_bvec(struct kunit *test)
b = 0;
patt = 0;
memset(scratch, 0, bufsize);
- for (pr = bvec_test_ranges; pr->from >= 0; pr++, b++) {
+ for (pr = bvec_test_ranges; pr->page >= 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;
- }
-
+ iov_kunit_check_pattern(test, buffer, scratch, bufsize);
KUNIT_SUCCEED();
}

@@ -341,7 +355,7 @@ static void __init iov_kunit_copy_from_bvec(struct kunit *test)
/* Build the expected image in the main buffer. */
i = 0;
memset(buffer, 0, bufsize);
- for (pr = bvec_test_ranges; pr->from >= 0; pr++) {
+ for (pr = bvec_test_ranges; pr->page >= 0; pr++) {
size_t patt = pr->page * PAGE_SIZE;

for (j = pr->from; j < pr->to; j++) {
@@ -352,13 +366,7 @@ static void __init iov_kunit_copy_from_bvec(struct kunit *test)
}
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;
- }
-
+ iov_kunit_check_pattern(test, buffer, scratch, bufsize);
KUNIT_SUCCEED();
}

@@ -409,7 +417,7 @@ static void __init iov_kunit_copy_to_xarray(struct kunit *test)
struct page **spages, **bpages;
u8 *scratch, *buffer;
size_t bufsize, npages, size, copied;
- int i, patt;
+ int i;

bufsize = 0x100000;
npages = bufsize / PAGE_SIZE;
@@ -426,7 +434,7 @@ static void __init iov_kunit_copy_to_xarray(struct kunit *test)
iov_kunit_load_xarray(test, &iter, READ, xarray, bpages, npages);

i = 0;
- for (pr = kvec_test_ranges; pr->from >= 0; pr++) {
+ for (pr = kvec_test_ranges; pr->page >= 0; pr++) {
size = pr->to - pr->from;
KUNIT_ASSERT_LE(test, pr->to, bufsize);

@@ -439,20 +447,8 @@ static void __init iov_kunit_copy_to_xarray(struct kunit *test)
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;
- }
-
+ iov_kunit_build_to_reference_pattern(test, scratch, bufsize, kvec_test_ranges);
+ iov_kunit_check_pattern(test, buffer, scratch, bufsize);
KUNIT_SUCCEED();
}

@@ -467,7 +463,7 @@ static void __init iov_kunit_copy_from_xarray(struct kunit *test)
struct page **spages, **bpages;
u8 *scratch, *buffer;
size_t bufsize, npages, size, copied;
- int i, j;
+ int i;

bufsize = 0x100000;
npages = bufsize / PAGE_SIZE;
@@ -484,7 +480,7 @@ static void __init iov_kunit_copy_from_xarray(struct kunit *test)
iov_kunit_load_xarray(test, &iter, READ, xarray, bpages, npages);

i = 0;
- for (pr = kvec_test_ranges; pr->from >= 0; pr++) {
+ for (pr = kvec_test_ranges; pr->page >= 0; pr++) {
size = pr->to - pr->from;
KUNIT_ASSERT_LE(test, pr->to, bufsize);

@@ -497,25 +493,8 @@ static void __init iov_kunit_copy_from_xarray(struct kunit *test)
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;
- }
-
+ iov_kunit_build_from_reference_pattern(test, buffer, bufsize, kvec_test_ranges);
+ iov_kunit_check_pattern(test, buffer, scratch, bufsize);
KUNIT_SUCCEED();
}

@@ -573,7 +552,7 @@ static void __init iov_kunit_extract_pages_kvec(struct kunit *test)
while (from == pr->to) {
pr++;
from = pr->from;
- if (from < 0)
+ if (pr->page < 0)
goto stop;
}
ix = from / PAGE_SIZE;
@@ -651,7 +630,7 @@ static void __init iov_kunit_extract_pages_bvec(struct kunit *test)
while (from == pr->to) {
pr++;
from = pr->from;
- if (from < 0)
+ if (pr->page < 0)
goto stop;
}
ix = pr->page + from / PAGE_SIZE;
@@ -698,7 +677,7 @@ static void __init iov_kunit_extract_pages_xarray(struct kunit *test)
iov_kunit_create_buffer(test, &bpages, npages);
iov_kunit_load_xarray(test, &iter, READ, xarray, bpages, npages);

- for (pr = kvec_test_ranges; pr->from >= 0; pr++) {
+ for (pr = kvec_test_ranges; pr->page >= 0; pr++) {
from = pr->from;
size = pr->to - from;
KUNIT_ASSERT_LE(test, pr->to, bufsize);