Test cases for fbdev

index e5efeb93..a803f445 100644
@@ -37,28 +37,17 @@
 
 #include "igt.h"
 
-igt_main
+static void mode_tests(int fd)
 {
 	struct fb_var_screeninfo var_info;
 	struct fb_fix_screeninfo fix_info;
-	int fd = -1;
 
-	/*
-	 * Should this test focus on the fbdev independent of any drm driver,
-	 * or should it look for fbdev of a particular device?
-	 */
 	igt_fixture {
-		fd = open("/dev/fb0", O_RDWR);
-		if (fd < 0) {
-			drm_load_module(DRIVER_ANY);
-			fd = open("/dev/fb0", O_RDWR);
-		}
-		igt_require_f(fd != -1, "/dev/fb0\n");
-
 		igt_require(ioctl(fd, FBIOGET_VSCREENINFO, &var_info) == 0);
 		igt_require(ioctl(fd, FBIOGET_FSCREENINFO, &fix_info) == 0);
 	}
 
+	igt_describe("Check if screeninfo is valid");
 	igt_subtest("info") {
 		unsigned long size;
 

@@ -69,7 +58,17 @@ igt_main
 			     fix_info.line_length,
 			     fix_info.smem_len);
 	}
+}
+
+static void framebuffer_tests(int fd)
+{
+	struct fb_fix_screeninfo fix_info;
+
+	igt_fixture {
+		igt_require(ioctl(fd, FBIOGET_FSCREENINFO, &fix_info) == 0);
+	}
 
+	igt_describe("Check mmap operations on framebuffer memory");
 	igt_subtest("mmap") {
 		void *map;
 

@@ -82,6 +81,34 @@ igt_main
 		memset(map, 0, fix_info.smem_len);
 		munmap(map, fix_info.smem_len);
 	}
+}
+
+igt_main
+{
+	volatile int fd = -1;
+
+	/*
+	 * Should this test focus on the fbdev independent of any drm driver,
+	 * or should it look for fbdev of a particular device?
+	 */
+	igt_fixture {
+		fd = open("/dev/fb0", O_RDWR);
+		if (fd < 0) {
+			drm_load_module(DRIVER_ANY);
+			fd = open("/dev/fb0", O_RDWR);
+		}
+		igt_require_f(fd != -1, "/dev/fb0\n");
+	}
+
+	igt_describe("Check modesetting");
+	igt_subtest_group {
+		mode_tests(fd);
+	}
+
+	igt_describe("Check framebuffer access");
+	igt_subtest_group {
+		framebuffer_tests(fd);
+	}
 
 	igt_fixture {
 		close(fd);

index a803f445..eebd2a83 100644
@@ -63,22 +63,20 @@ static void mode_tests(int fd)
 static void framebuffer_tests(int fd)
 {
 	struct fb_fix_screeninfo fix_info;
+	void * volatile map;
 
 	igt_fixture {
 		igt_require(ioctl(fd, FBIOGET_FSCREENINFO, &fix_info) == 0);
-	}
-
-	igt_describe("Check mmap operations on framebuffer memory");
-	igt_subtest("mmap") {
-		void *map;
-
-		igt_require(fix_info.smem_len);
+		igt_assert(fix_info.smem_len);
 
 		map = mmap(NULL, fix_info.smem_len,
 			   PROT_WRITE, MAP_SHARED, fd, 0);
 		igt_assert(map != MAP_FAILED);
 
 		memset(map, 0, fix_info.smem_len);
+	}
+
+	igt_fixture {
 		munmap(map, fix_info.smem_len);
 	}
 }

index eebd2a83..d8c78a5e 100644
@@ -25,6 +25,7 @@
 
 #include "igt.h"
 
+#include <errno.h>
 #include <fcntl.h>
 #include <string.h>
 #include <sys/ioctl.h>

@@ -64,6 +65,7 @@ static void framebuffer_tests(int fd)
 {
 	struct fb_fix_screeninfo fix_info;
 	void * volatile map;
+	void * volatile buf;
 
 	igt_fixture {
 		igt_require(ioctl(fd, FBIOGET_FSCREENINFO, &fix_info) == 0);

@@ -73,10 +75,33 @@ static void framebuffer_tests(int fd)
 			   PROT_WRITE, MAP_SHARED, fd, 0);
 		igt_assert(map != MAP_FAILED);
 
+		buf = malloc(fix_info.smem_len);
+		igt_require(buf);
+	}
+
+	igt_describe("Check read operations on framebuffer memory");
+	igt_subtest("read") {
+		ssize_t ret;
+		int cmp;
+
+		/* fill framebuffer with 0 and compare */
 		memset(map, 0, fix_info.smem_len);
+		ret = pread(fd, buf, fix_info.smem_len, 0);
+		igt_assert_f(ret == (ssize_t)fix_info.smem_len, "pread failed, ret=%zd\n", ret);
+		cmp = memcmp(map, buf, fix_info.smem_len);
+		igt_assert_f(!cmp, "read buffer differs from mapped framebuffer for 0\n");
+
+		/* fill framebuffer with 0x55 and compare */
+		memset(map, 0x55, fix_info.smem_len);
+		ret = pread(fd, buf, fix_info.smem_len, 0);
+		igt_assert_f(ret == (ssize_t)fix_info.smem_len, "pread failed, ret=%zd\n", ret);
+		cmp = memcmp(map, buf, fix_info.smem_len);
+		igt_assert_f(!cmp, "read buffer differs from mapped framebuffer for 0x55\n");
 	}
 
 	igt_fixture {
+		free(buf);
+		memset(map, 0, fix_info.smem_len); // don't leave garbage on the screen
 		munmap(map, fix_info.smem_len);
 	}
 }

index d8c78a5e..be9e95c1 100644
@@ -64,10 +64,13 @@ static void mode_tests(int fd)
 static void framebuffer_tests(int fd)
 {
 	struct fb_fix_screeninfo fix_info;
-	void * volatile map;
-	void * volatile buf;
+	unsigned char * volatile map;
+	unsigned char * volatile buf;
+	volatile size_t pagesize;
 
 	igt_fixture {
+		long ret;
+
 		igt_require(ioctl(fd, FBIOGET_FSCREENINFO, &fix_info) == 0);
 		igt_assert(fix_info.smem_len);
 

@@ -77,6 +80,10 @@ static void framebuffer_tests(int fd)
 
 		buf = malloc(fix_info.smem_len);
 		igt_require(buf);
+
+		ret = sysconf(_SC_PAGESIZE);
+		igt_require(ret != -1);
+		pagesize = ret;
 	}
 
 	igt_describe("Check read operations on framebuffer memory");

@@ -99,6 +106,35 @@ static void framebuffer_tests(int fd)
 		igt_assert_f(!cmp, "read buffer differs from mapped framebuffer for 0x55\n");
 	}
 
+	igt_describe("Check read operations on unaligned locations in framebuffer memory");
+	igt_subtest("unaligned-read") {
+		off_t off;
+		size_t len;
+		ssize_t ret;
+		const unsigned char *pos;
+
+		off = pagesize + (pagesize >> 2); // 1.25 * pagesize
+		len = (pagesize << 2) + (pagesize >> 1); // 4.5 * pagesize
+		igt_require_f((off + len) < fix_info.smem_len, "framebuffer too small to test\n");
+
+		/* read at unaligned location and compare */
+		memset(map, 0, fix_info.smem_len);
+		memset(&map[off], 0x55, len);
+		memset(buf, 0xff, fix_info.smem_len);
+		ret = pread(fd, &buf[off], len, off);
+		igt_assert_f(ret == (ssize_t)len, "pread failed, ret=%zd\n", ret);
+		pos = memchr(buf, 0x55, fix_info.smem_len);
+		igt_assert_f(pos, "0x55 not found within read buffer\n");
+		igt_assert_f(pos == &buf[off], "0x55 found at pos %zu, expected %lld\n",
+			     pos - buf, (long long)off);
+		pos = memchr(&buf[off], 0xff, fix_info.smem_len - off);
+		igt_assert_f(pos, "0xff not found within read buffer\n");
+		igt_assert_f(pos == &buf[off + len], "0xff found at pos %zu, expected %lld\n",
+			     pos - buf, (long long)(off + len));
+		pos = memchr(&buf[off + len], 0x55, fix_info.smem_len - off + len);
+		igt_assert_f(pos, "found 0x55 at pos %zu, none expected\n", pos - buf);
+	}
+
 	igt_fixture {
 		free(buf);
 		memset(map, 0, fix_info.smem_len); // don't leave garbage on the screen

index be9e95c1..23ff146c 100644
@@ -135,6 +135,26 @@ static void framebuffer_tests(int fd)
 		igt_assert_f(pos, "found 0x55 at pos %zu, none expected\n", pos - buf);
 	}
 
+	igt_describe("Check write operations on framebuffer memory");
+	igt_subtest("write") {
+		ssize_t ret;
+		int cmp;
+
+		/* write 0 to framebuffer and compare */
+		memset(buf, 0, fix_info.smem_len);
+		ret = pwrite(fd, buf, fix_info.smem_len, 0);
+		igt_assert_f(ret == (ssize_t)fix_info.smem_len, "pwrite failed, ret=%zd\n", ret);
+		cmp = memcmp(map, buf, fix_info.smem_len);
+		igt_assert_f(!cmp, "write buffer differs from mapped framebuffer for 0\n");
+
+		/* write 0x55 to framebuffer and compare */
+		memset(buf, 0x55, fix_info.smem_len);
+		ret = pwrite(fd, buf, fix_info.smem_len, 0);
+		igt_assert_f(ret == (ssize_t)fix_info.smem_len, "pwrite failed, ret=%zd\n", ret);
+		cmp = memcmp(map, buf, fix_info.smem_len);
+		igt_assert_f(!cmp, "write buffer differs from mapped framebuffer for 0\n");
+	}
+
 	igt_fixture {
 		free(buf);
 		memset(map, 0, fix_info.smem_len); // don't leave garbage on the screen

index 23ff146c..c4cb357f 100644
@@ -155,6 +155,35 @@ static void framebuffer_tests(int fd)
 		igt_assert_f(!cmp, "write buffer differs from mapped framebuffer for 0\n");
 	}
 
+	igt_describe("Check write operations on unaligned locations in framebuffer memory");
+	igt_subtest("unaligned-write") {
+		off_t off;
+		size_t len;
+		ssize_t ret;
+		const unsigned char *pos;
+
+		off = pagesize + (pagesize >> 2); // 1.25 * pagesize
+		len = (pagesize << 2) + (pagesize >> 1); // 4.5 * pagesize
+		igt_require_f((off + len) < fix_info.smem_len, "framebuffer too small to test\n");
+
+		/* read at unaligned location and compare */
+		memset(map, 0xff, fix_info.smem_len);
+		memset(buf, 0, fix_info.smem_len);
+		memset(&buf[off], 0x55, len);
+		ret = pwrite(fd, &buf[off], len, off);
+		igt_assert_f(ret == (ssize_t)len, "pwrite failed, ret=%zd\n", ret);
+		pos = memchr(map, 0x55, fix_info.smem_len);
+		igt_assert_f(pos, "0x55 not found within framebuffer\n");
+		igt_assert_f(pos == &map[off], "0x55 found at pos %zu, expected %lld\n",
+			     pos - map, (long long)off);
+		pos = memchr(&map[off], 0xff, fix_info.smem_len - off);
+		igt_assert_f(pos, "0xff not found within framebuffer\n");
+		igt_assert_f(pos == &map[off + len], "0xff found at pos %zu, expected %lld\n",
+			     pos - map, (long long)(off + len));
+		pos = memchr(&map[off + len], 0x55, fix_info.smem_len - off + len);
+		igt_assert_f(pos, "found 0x55 at pos %zu, none expected\n", pos - map);
+	}
+
 	igt_fixture {
 		free(buf);
 		memset(map, 0, fix_info.smem_len); // don't leave garbage on the screen

index c4cb357f..62aa99b4 100644
@@ -78,7 +78,8 @@ static void framebuffer_tests(int fd)
 			   PROT_WRITE, MAP_SHARED, fd, 0);
 		igt_assert(map != MAP_FAILED);
 
-		buf = malloc(fix_info.smem_len);
+		/* allocate two additional bytes for eof test */
+		buf = malloc(fix_info.smem_len + 2);
 		igt_require(buf);
 
 		ret = sysconf(_SC_PAGESIZE);

@@ -184,6 +185,50 @@ static void framebuffer_tests(int fd)
 		igt_assert_f(pos, "found 0x55 at pos %zu, none expected\n", pos - map);
 	}
 
+	igt_describe("Check framebuffer access near EOF");
+	igt_subtest("eof") {
+		unsigned long lastindex = fix_info.smem_len - 1;
+		unsigned char *maplast = &((unsigned char *)map)[lastindex];
+		unsigned char *buflast = &((unsigned char *)buf)[lastindex];
+		ssize_t ret;
+
+		*buflast = 0x55;
+
+		/* write across EOF; set remaining bytes */
+		ret = pwrite(fd, buflast, 2, lastindex);
+		igt_assert_f(ret == 1, "write crossed EOF, ret=%zd\n", ret);
+		igt_assert_f(*maplast == *buflast, "write buffer differs from mapped framebuffer at final byte, "
+						   "maplast=%u buflast=%u\n", *maplast, *buflast);
+
+		/* write at EOF; get ENOSPC */
+		ret = pwrite(fd, &buflast[1], 1, lastindex + 1);
+		igt_assert_f((ret == -1) && (errno == ENOSPC), "write at EOF, ret=%zd\n", ret);
+
+		*maplast = 0;
+
+		/* write final byte */
+		ret = pwrite(fd, buflast, 1, lastindex);
+		igt_assert_f(ret == 1, "write before EOF, ret=%zd\n", ret);
+		igt_assert_f(*maplast == *buflast, "write buffer differs from mapped framebuffer at final byte, "
+						   "maplast=%u buflast=%u\n", *maplast, *buflast);
+
+		/* write after EOF; get EFBIG */
+		ret = pwrite(fd, &buflast[2], 1, lastindex + 2);
+		igt_assert_f((ret == -1) && (errno == EFBIG), "write after EOF, ret=%zd\n", ret);
+
+		*maplast = 0;
+
+		/* read across the EOF; get remaining bytes */
+		ret = pread(fd, buflast, 2, lastindex);
+		igt_assert_f(ret == 1, "read before EOF, ret=%zd\n", ret);
+		igt_assert_f(*maplast == *buflast, "read buffer differs from mapped framebuffer at final byte, "
+						   "maplast=%u buflast=%u\n", *maplast, *buflast);
+
+		/* read after EOF; get 0 */
+		ret = pread(fd, &buflast[1], 1, lastindex + 1);
+		igt_assert_f(ret == 0, "read at EOF, ret=%zd\n", ret);
+	}
+
 	igt_fixture {
 		free(buf);
 		memset(map, 0, fix_info.smem_len); // don't leave garbage on the screen

index 62aa99b4..c6139124 100644
@@ -229,6 +229,17 @@ static void framebuffer_tests(int fd)
 		igt_assert_f(ret == 0, "read at EOF, ret=%zd\n", ret);
 	}
 
+	igt_describe("Check framebuffer access with NULL");
+	igt_subtest("nullptr") {
+		ssize_t ret;
+
+		ret = pread(fd, NULL, fix_info.smem_len, 0);
+		igt_require_f((ret == -1) && (errno == EFAULT), "reading into NULL did not return EFAULT, ret=%zd\n", ret);
+
+		ret = pwrite(fd, NULL, fix_info.smem_len, 0);
+		igt_require_f((ret == -1) && (errno == EFAULT), "writing from NULL did not return EFAULT, ret=%zd\n", ret);
+	}
+
 	igt_fixture {
 		free(buf);
 		memset(map, 0, fix_info.smem_len); // don't leave garbage on the screen