[PATCH 1/6] igt_kms: don't leak the mmap used for cairo

[Paulo Zanoni <przanoni@gmail.com>]

From: Paulo Zanoni <paulo.r.zanoni@intel.com>

When we call kmstest_get_cairo_ctx() and create a context, we do a
gem_mmap. The problem is that we lose the mmap pointer, so we leak it.
This patch stores the pointer and frees it at kmstest_remove_fb.

Huge test suites like kms_flip do this operation thousands of times,
which makes the virtual memory size increase until the test suite gets
killed. Today, without this patch, we can't even run 50% of the
kms_flip tests due to this problem. To test this, just "./kms_flip",
then run "top" and sort it by the VIRT column.

Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
---
 lib/igt_kms.c | 15 ++++++++++-----
 lib/igt_kms.h |  1 +
 2 files changed, 11 insertions(+), 5 deletions(-)

diff --git a/lib/igt_kms.c b/lib/igt_kms.c
index 57795b1..f032cd3 100644
--- a/lib/igt_kms.c
+++ b/lib/igt_kms.c
@@ -303,6 +303,7 @@ unsigned int kmstest_create_fb(int fd, int width, int height, int bpp,
 	fb->height = height;
 	fb->tiling = tiled;
 	fb->drm_format = bpp_depth_to_drm_format(bpp, depth);
+	fb->fb_ptr = NULL;
 
 	return fb->fb_id;
 }
@@ -353,6 +354,7 @@ unsigned int kmstest_create_fb2(int fd, int width, int height, uint32_t format,
 	fb->tiling = tiled;
 	fb->drm_format = format;
 	fb->fb_id = fb_id;
+	fb->fb_ptr = NULL;
 
 	return fb_id;
 }
@@ -372,13 +374,14 @@ static cairo_surface_t *create_image_surface(int fd, struct kmstest_fb *fb)
 {
 	cairo_surface_t *surface;
 	cairo_format_t cformat;
-	void *fb_ptr;
 
 	cformat = drm_format_to_cairo(fb->drm_format);
-	fb_ptr = gem_mmap(fd, fb->gem_handle, fb->size, PROT_READ | PROT_WRITE);
-	surface = cairo_image_surface_create_for_data((unsigned char *)fb_ptr,
-						   cformat, fb->width,
-						   fb->height, fb->stride);
+	fb->fb_ptr = gem_mmap(fd, fb->gem_handle, fb->size,
+			      PROT_READ | PROT_WRITE);
+	surface = cairo_image_surface_create_for_data(
+						(unsigned char *)fb->fb_ptr,
+						cformat, fb->width,
+						fb->height, fb->stride);
 	assert(surface);
 
 	return surface;
@@ -423,6 +426,8 @@ void kmstest_remove_fb(int fd, struct kmstest_fb *fb)
 {
 	if (fb->cairo_ctx)
 		cairo_destroy(fb->cairo_ctx);
+	if (fb->fb_ptr)
+		munmap(fb->fb_ptr, fb->size);
 	do_or_die(drmModeRmFB(fd, fb->fb_id));
 	gem_close(fd, fb->gem_handle);
 }
diff --git a/lib/igt_kms.h b/lib/igt_kms.h
index f61f8e5..f9494d0 100644
--- a/lib/igt_kms.h
+++ b/lib/igt_kms.h
@@ -55,6 +55,7 @@ struct kmstest_fb {
 	unsigned tiling;
 	unsigned size;
 	cairo_t *cairo_ctx;
+	void *fb_ptr;
 };
 
 enum kmstest_text_align {
-- 
1.8.3.1