[PATCH v3 5/5] tools/testing/scatterlist: Test new __sg_alloc_table_from_pages

From: Tvrtko Ursulin
Date: Wed Sep 06 2017 - 10:55:19 EST

From: Tvrtko Ursulin <tvrtko.ursulin@xxxxxxxxx>

Exercise the new __sg_alloc_table_from_pages API (and through
it also the old sg_alloc_table_from_pages), checking that the
created table has the expected number of segments depending on
the sequence of input pages and other conditions.

v2: Move to data driven for readability.
v3: Add some more testcases and -fsanitize=undefined. (Chris Wilson)

Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@xxxxxxxxx>
Cc: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx>
Cc: linux-kernel@xxxxxxxxxxxxxxx
Reviewed-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx>
---
tools/testing/scatterlist/Makefile | 30 +++++++++
tools/testing/scatterlist/linux/mm.h | 125 +++++++++++++++++++++++++++++++++++
tools/testing/scatterlist/main.c | 79 ++++++++++++++++++++++
3 files changed, 234 insertions(+)
create mode 100644 tools/testing/scatterlist/Makefile
create mode 100644 tools/testing/scatterlist/linux/mm.h
create mode 100644 tools/testing/scatterlist/main.c

diff --git a/tools/testing/scatterlist/Makefile b/tools/testing/scatterlist/Makefile
new file mode 100644
index 000000000000..933c3a6e4d77
--- /dev/null
+++ b/tools/testing/scatterlist/Makefile
@@ -0,0 +1,30 @@
+CFLAGS += -I. -I../../include -g -O2 -Wall -fsanitize=address
+LDFLAGS += -fsanitize=address -fsanitize=undefined
+TARGETS = main
+OFILES = main.o scatterlist.o
+
+ifeq ($(BUILD), 32)
+ CFLAGS += -m32
+ LDFLAGS += -m32
+endif
+
+targets: include $(TARGETS)
+
+main: $(OFILES)
+
+clean:
+ $(RM) $(TARGETS) $(OFILES) scatterlist.c linux/scatterlist.h linux/highmem.h linux/kmemleak.h asm/io.h
+ @rmdir asm
+
+scatterlist.c: ../../../lib/scatterlist.c
+ @sed -e 's/^static //' -e 's/__always_inline //' -e 's/inline //' < $< > $@
+
+.PHONY: include
+
+include: ../../../include/linux/scatterlist.h
+ @mkdir -p linux
+ @mkdir -p asm
+ @touch asm/io.h
+ @touch linux/highmem.h
+ @touch linux/kmemleak.h
+ @cp $< linux/scatterlist.h
diff --git a/tools/testing/scatterlist/linux/mm.h b/tools/testing/scatterlist/linux/mm.h
new file mode 100644
index 000000000000..ccbb248ebdc1
--- /dev/null
+++ b/tools/testing/scatterlist/linux/mm.h
@@ -0,0 +1,125 @@
+#ifndef _LINUX_MM_H
+#define _LINUX_MM_H
+
+#include <assert.h>
+#include <string.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <limits.h>
+#include <stdio.h>
+
+typedef unsigned long dma_addr_t;
+
+#define unlikely
+
+#define BUG_ON(x) assert(!(x))
+
+#define WARN_ON(condition) ({ \
+ int __ret_warn_on = !!(condition); \
+ unlikely(__ret_warn_on); \
+})
+
+#define WARN_ON_ONCE(condition) ({ \
+ int __ret_warn_on = !!(condition); \
+ if (unlikely(__ret_warn_on)) \
+ assert(0); \
+ unlikely(__ret_warn_on); \
+})
+
+#define PAGE_SIZE (4096)
+#define PAGE_SHIFT (12)
+#define PAGE_MASK (~(PAGE_SIZE-1))
+
+#define __ALIGN_KERNEL(x, a) __ALIGN_KERNEL_MASK(x, (typeof(x))(a) - 1)
+#define __ALIGN_KERNEL_MASK(x, mask) (((x) + (mask)) & ~(mask))
+#define ALIGN(x, a) __ALIGN_KERNEL((x), (a))
+
+#define PAGE_ALIGN(addr) ALIGN(addr, PAGE_SIZE)
+
+#define offset_in_page(p) ((unsigned long)(p) & ~PAGE_MASK)
+
+#define virt_to_page(x) ((void *)x)
+#define page_address(x) ((void *)x)
+
+static inline unsigned long page_to_phys(struct page *page)
+{
+ assert(0);
+
+ return 0;
+}
+
+#define page_to_pfn(page) ((unsigned long)(page) / PAGE_SIZE)
+#define pfn_to_page(pfn) (void *)((pfn) * PAGE_SIZE)
+#define nth_page(page,n) pfn_to_page(page_to_pfn((page)) + (n))
+
+#define __min(t1, t2, min1, min2, x, y) ({ \
+ t1 min1 = (x); \
+ t2 min2 = (y); \
+ (void) (&min1 == &min2); \
+ min1 < min2 ? min1 : min2; })
+
+#define ___PASTE(a,b) a##b
+#define __PASTE(a,b) ___PASTE(a,b)
+
+#define __UNIQUE_ID(prefix) __PASTE(__PASTE(__UNIQUE_ID_, prefix), __COUNTER__)
+
+#define min(x, y) \
+ __min(typeof(x), typeof(y), \
+ __UNIQUE_ID(min1_), __UNIQUE_ID(min2_), \
+ x, y)
+
+#define min_t(type, x, y) \
+ __min(type, type, \
+ __UNIQUE_ID(min1_), __UNIQUE_ID(min2_), \
+ x, y)
+
+#define preemptible() (1)
+
+static inline void *kmap(struct page *page)
+{
+ assert(0);
+
+ return NULL;
+}
+
+static inline void *kmap_atomic(struct page *page)
+{
+ assert(0);
+
+ return NULL;
+}
+
+static inline void kunmap(void *addr)
+{
+ assert(0);
+}
+
+static inline void kunmap_atomic(void *addr)
+{
+ assert(0);
+}
+
+static inline unsigned long __get_free_page(unsigned int flags)
+{
+ return (unsigned long)malloc(PAGE_SIZE);
+}
+
+static inline void free_page(unsigned long page)
+{
+ free((void *)page);
+}
+
+static inline void *kmalloc(unsigned int size, unsigned int flags)
+{
+ return malloc(size);
+}
+
+#define kfree(x) free(x)
+
+#define kmemleak_alloc(a, b, c, d)
+#define kmemleak_free(a)
+
+#define PageSlab(p) (0)
+#define flush_kernel_dcache_page(p)
+
+#endif
diff --git a/tools/testing/scatterlist/main.c b/tools/testing/scatterlist/main.c
new file mode 100644
index 000000000000..0a1464181226
--- /dev/null
+++ b/tools/testing/scatterlist/main.c
@@ -0,0 +1,79 @@
+#include <stdio.h>
+#include <assert.h>
+
+#include <linux/scatterlist.h>
+
+#define MAX_PAGES (64)
+
+static void set_pages(struct page **pages, const unsigned *array, unsigned num)
+{
+ unsigned int i;
+
+ assert(num < MAX_PAGES);
+ for (i = 0; i < num; i++)
+ pages[i] = (struct page *)(unsigned long)
+ ((1 + array[i]) * PAGE_SIZE);
+}
+
+#define pfn(...) (unsigned []){ __VA_ARGS__ }
+
+int main(void)
+{
+ const unsigned int sgmax = SCATTERLIST_MAX_SEGMENT;
+ struct test {
+ int alloc_ret;
+ unsigned num_pages;
+ unsigned *pfn;
+ unsigned size;
+ unsigned int max_seg;
+ unsigned int expected_segments;
+ } *test, tests[] = {
+ { -EINVAL, 1, pfn(0), PAGE_SIZE, PAGE_SIZE + 1, 1 },
+ { -EINVAL, 1, pfn(0), PAGE_SIZE, 0, 1 },
+ { -EINVAL, 1, pfn(0), PAGE_SIZE, sgmax + 1, 1 },
+ { 0, 1, pfn(0), PAGE_SIZE, sgmax, 1 },
+ { 0, 1, pfn(0), 1, sgmax, 1 },
+ { 0, 2, pfn(0, 1), 2 * PAGE_SIZE, sgmax, 1 },
+ { 0, 2, pfn(1, 0), 2 * PAGE_SIZE, sgmax, 2 },
+ { 0, 3, pfn(0, 1, 2), 3 * PAGE_SIZE, sgmax, 1 },
+ { 0, 3, pfn(0, 2, 1), 3 * PAGE_SIZE, sgmax, 3 },
+ { 0, 3, pfn(0, 1, 3), 3 * PAGE_SIZE, sgmax, 2 },
+ { 0, 3, pfn(1, 2, 4), 3 * PAGE_SIZE, sgmax, 2 },
+ { 0, 3, pfn(1, 3, 4), 3 * PAGE_SIZE, sgmax, 2 },
+ { 0, 4, pfn(0, 1, 3, 4), 4 * PAGE_SIZE, sgmax, 2 },
+ { 0, 5, pfn(0, 1, 3, 4, 5), 5 * PAGE_SIZE, sgmax, 2 },
+ { 0, 5, pfn(0, 1, 3, 4, 6), 5 * PAGE_SIZE, sgmax, 3 },
+ { 0, 5, pfn(0, 1, 2, 3, 4), 5 * PAGE_SIZE, sgmax, 1 },
+ { 0, 5, pfn(0, 1, 2, 3, 4), 5 * PAGE_SIZE, 2 * PAGE_SIZE, 3 },
+ { 0, 6, pfn(0, 1, 2, 3, 4, 5), 6 * PAGE_SIZE, 2 * PAGE_SIZE, 3 },
+ { 0, 6, pfn(0, 2, 3, 4, 5, 6), 6 * PAGE_SIZE, 2 * PAGE_SIZE, 4 },
+ { 0, 6, pfn(0, 1, 3, 4, 5, 6), 6 * PAGE_SIZE, 2 * PAGE_SIZE, 3 },
+ { 0, 0, NULL, 0, 0, 0 },
+ };
+ unsigned int i;
+
+ for (i = 0, test = tests; test->expected_segments; test++, i++) {
+ struct page *pages[MAX_PAGES];
+ struct sg_table st;
+ int ret;
+
+ set_pages(pages, test->pfn, test->num_pages);
+
+ ret = __sg_alloc_table_from_pages(&st, pages, test->num_pages,
+ 0, test->size, test->max_seg,
+ GFP_KERNEL);
+ assert(ret == test->alloc_ret);
+
+ if (test->alloc_ret)
+ continue;
+
+ assert(st.nents == test->expected_segments);
+ assert(st.orig_nents == test->expected_segments);
+
+ sg_free_table(&st);
+ }
+
+ assert(i == (sizeof(tests) / sizeof(tests[0])) - 1);
+
+ return 0;
+}
--
2.9.5