[LTP] [PATCH v6] mmap01: Convert to new API

[LTP] [PATCH v6] mmap01: Convert to new API

[Ricardo B. Marliere via ltp]

From: Ricardo B. Marliere <rbm@suse.com>

Refactor the old mmap01 code into the new LTP API.

Signed-off-by: Ricardo B. Marliere <rbm@suse.com>
---
Changes in v6:
- Removed call to set_file() in setup(), otherwise it's called twice in the
  first run().
- Link to v5: https://lore.kernel.org/r/20241212-convert_mmap01-v5-1-258d9d78bb83@suse.com

Changes in v5:
- Reset file for each test run in a new function set_file().
- Restored STRING to its original content.
- Added call to SAFE_MUNMAP in the child process.
- Link to v4: https://lore.kernel.org/ltp/20241210-convert_mmap01-v4-1-c2338a2ca071@suse.com/

Changes in v4:
- Move file check logic into a new function check_file() instead of using a
  system() call to grep.
- Link to v3: https://lore.kernel.org/r/20241118-convert_mmap01-v3-1-b275c90035f5@suse.com/

Changes in v3:
- Use SAFE_MMAP and SAFE_MUNMAP as suggested by Jan Stancek.
- Re-aligned a few comments.
- Link to v2: https://lore.kernel.org/r/20241114-convert_mmap01-v2-1-a8a1379dec89@suse.com

Changes in v2:
- Fixed metadata alignment.
- Link to v1: https://lore.kernel.org/r/20241113-convert_mmap01-v1-1-e7d60e7404c4@suse.com
---
 testcases/kernel/syscalls/mmap/mmap01.c | 263 +++++++++++++-------------------
 1 file changed, 107 insertions(+), 156 deletions(-)

diff --git a/testcases/kernel/syscalls/mmap/mmap01.c b/testcases/kernel/syscalls/mmap/mmap01.c
index 99266b57ffc16e6c3a0e31a2c87d0f8106f429e5..0ada71ee5d066be44fa52d8c21d8e21685d9dc44 100644
--- a/testcases/kernel/syscalls/mmap/mmap01.c
+++ b/testcases/kernel/syscalls/mmap/mmap01.c
@@ -1,194 +1,145 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * Copyright (c) International Business Machines  Corp., 2001
+ * Copyright (c) 2024 Ricardo B. Marliere <rbm@suse.com>
  *
- * This program is free software;  you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY;  without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
- * the GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program;  if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ * HISTORY
+ *	07/2001 Ported by Wayne Boyer
  */
 
-/*
- * Test Description:
- *  Verify that, mmap() succeeds when used to map a file where size of the
- *  file is not a multiple of the page size, the memory area beyond the end
- *  of the file to the end of the page is accessible. Also, verify that
- *  this area is all zeroed and the modifications done to this area are
- *  not written to the file.
+/*\
+ * [Description]
  *
- * Expected Result:
- *  mmap() should succeed returning the address of the mapped region.
- *  The memory area beyond the end of file to the end of page should be
- *  filled with zero.
- *  The changes beyond the end of file should not get written to the file.
+ * Verify that mmap() succeeds when used to map a file where size of the
+ * file is not a multiple of the page size, the memory area beyond the end
+ * of the file to the end of the page is accessible. Also, verify that
+ * this area is all zeroed and the modifications done to this area are
+ * not written to the file.
  *
- * HISTORY
- *	07/2001 Ported by Wayne Boyer
+ * mmap() should succeed returning the address of the mapped region.
+ * The memory area beyond the end of file to the end of page should be
+ * filled with zero.
+ * The changes beyond the end of file should not get written to the file.
  */
-#include <stdio.h>
-#include <stdlib.h>
-#include <sys/types.h>
-#include <errno.h>
-#include <unistd.h>
-#include <fcntl.h>
-#include <string.h>
-#include <signal.h>
-#include <stdint.h>
-#include <sys/stat.h>
-#include <sys/mman.h>
-#include <sys/shm.h>
-
-#include "test.h"
-
-#define TEMPFILE	"mmapfile"
-
-char *TCID = "mmap01";
-int TST_TOTAL = 1;
+
+#include "tst_test.h"
+
+#define TEMPFILE "mmapfile"
+#define STRING "hello world\n"
 
 static char *addr;
 static char *dummy;
 static size_t page_sz;
 static size_t file_sz;
 static int fildes;
-static char cmd_buffer[BUFSIZ];
 
-static void setup(void);
-static void cleanup(void);
-
-int main(int ac, char **av)
+static void check_file(void)
 {
-	int lc;
-
-	tst_parse_opts(ac, av, NULL, NULL);
-
-	setup();
-
-	for (lc = 0; TEST_LOOPING(lc); lc++) {
-
-		tst_count = 0;
-
-		/*
-		 * Call mmap to map the temporary file beyond EOF
-		 * with write access.
-		 */
-		errno = 0;
-		addr = mmap(NULL, page_sz, PROT_READ | PROT_WRITE,
-			    MAP_FILE | MAP_SHARED, fildes, 0);
-
-		/* Check for the return value of mmap() */
-		if (addr == MAP_FAILED) {
-			tst_resm(TFAIL | TERRNO, "mmap of %s failed", TEMPFILE);
-			continue;
-		}
-
-		/*
-		 * Check if mapped memory area beyond EOF are
-		 * zeros and changes beyond EOF are not written
-		 * to file.
-		 */
-		if (memcmp(&addr[file_sz], dummy, page_sz - file_sz)) {
-			tst_brkm(TFAIL, cleanup,
-				 "mapped memory area contains invalid "
-				 "data");
-		}
-
-		/*
-		 * Initialize memory beyond file size
-		 */
-		addr[file_sz] = 'X';
-		addr[file_sz + 1] = 'Y';
-		addr[file_sz + 2] = 'Z';
-
-		/*
-		 * Synchronize the mapped memory region
-		 * with the file.
-		 */
-		if (msync(addr, page_sz, MS_SYNC) != 0) {
-			tst_brkm(TFAIL | TERRNO, cleanup,
-				 "failed to synchronize mapped file");
-		}
-
-		/*
-		 * Now, Search for the pattern 'XYZ' in the
-		 * temporary file.  The pattern should not be
-		 * found and the return value should be 1.
-		 */
-		if (system(cmd_buffer) != 0) {
-			tst_resm(TPASS,
-				 "Functionality of mmap() successful");
-		} else {
-			tst_resm(TFAIL,
-				 "Specified pattern found in file");
-		}
-
-		/* Clean up things in case we are looping */
-		/* Unmap the mapped memory */
-		if (munmap(addr, page_sz) != 0) {
-			tst_brkm(TFAIL | TERRNO, NULL, "munmap failed");
-		}
-	}
+	int i, fildes, buf_len = sizeof(STRING) + 3;
+	char buf[buf_len];
 
-	cleanup();
-	tst_exit();
-}
+	fildes = SAFE_OPEN(TEMPFILE, O_RDONLY);
+	SAFE_READ(0, fildes, buf, sizeof(buf));
 
-static void setup(void)
-{
-	struct stat stat_buf;
-	char Path_name[PATH_MAX];
-	char write_buf[] = "hello world\n";
+	for (i = 0; i < buf_len; i++)
+		if (buf[i] == 'X' || buf[i] == 'Y' || buf[i] == 'Z')
+			break;
 
-	tst_sig(FORK, DEF_HANDLER, cleanup);
+	if (i == buf_len)
+		tst_res(TPASS, "Functionality of mmap() successful");
+	else
+		tst_res(TFAIL, "Specified pattern found in file");
 
-	TEST_PAUSE;
+	SAFE_CLOSE(fildes);
+}
 
-	tst_tmpdir();
+static void set_file(void)
+{
+	char *write_buf = STRING;
+	struct stat stat_buf;
 
-	/* Get the path of temporary file to be created */
-	if (getcwd(Path_name, sizeof(Path_name)) == NULL) {
-		tst_brkm(TFAIL | TERRNO, cleanup,
-			 "getcwd failed to get current working directory");
+	/* Reset file */
+	if (fildes > 0) {
+		SAFE_CLOSE(fildes);
+		SAFE_UNLINK(TEMPFILE);
 	}
 
-	/* Creat a temporary file used for mapping */
-	if ((fildes = open(TEMPFILE, O_RDWR | O_CREAT, 0666)) < 0) {
-		tst_brkm(TFAIL, cleanup, "opening %s failed", TEMPFILE);
-	}
+	/* Create a temporary file used for mapping */
+	fildes = SAFE_OPEN(TEMPFILE, O_RDWR | O_CREAT, 0666);
 
 	/* Write some data into temporary file */
-	if (write(fildes, write_buf, strlen(write_buf)) != (long)strlen(write_buf)) {
-		tst_brkm(TFAIL, cleanup, "writing to %s", TEMPFILE);
-	}
+	SAFE_WRITE(SAFE_WRITE_ALL, fildes, write_buf, strlen(write_buf));
 
 	/* Get the size of temporary file */
-	if (stat(TEMPFILE, &stat_buf) < 0) {
-		tst_brkm(TFAIL | TERRNO, cleanup, "stat of %s failed",
-			 TEMPFILE);
-	}
+	SAFE_STAT(TEMPFILE, &stat_buf);
 	file_sz = stat_buf.st_size;
+}
 
-	page_sz = getpagesize();
+static void run(void)
+{
+	pid_t pid;
+
+	set_file();
+
+	addr = SAFE_MMAP(NULL, page_sz, PROT_READ | PROT_WRITE,
+			 MAP_FILE | MAP_SHARED, fildes, 0);
+
+	/*
+	 * Check if mapped memory area beyond EOF are zeros and changes beyond
+	 * EOF are not written to file.
+	 */
+	if (memcmp(&addr[file_sz], dummy, page_sz - file_sz))
+		tst_brk(TFAIL, "mapped memory area contains invalid data");
+
+	/*
+	 * Initialize memory beyond file size
+	 */
+	addr[file_sz] = 'X';
+	addr[file_sz + 1] = 'Y';
+	addr[file_sz + 2] = 'Z';
+
+	/*
+	 * Synchronize the mapped memory region with the file.
+	 */
+	if (msync(addr, page_sz, MS_SYNC) != 0) {
+		tst_res(TFAIL | TERRNO, "failed to synchronize mapped file");
+		return;
+	}
 
-	/* Allocate and initialize dummy string of system page size bytes */
-	if ((dummy = calloc(page_sz, sizeof(char))) == NULL) {
-		tst_brkm(TFAIL, cleanup, "calloc failed (dummy)");
+	/*
+	 * Now, search for the pattern 'XYZ' in the temporary file.
+	 * The pattern should not be found and the return value should be 1.
+	 */
+	pid = SAFE_FORK();
+	if (!pid) {
+		check_file();
+		SAFE_MUNMAP(addr, page_sz);
+		exit(0);
 	}
 
-	/* Create the command which will be executed in the test */
-	sprintf(cmd_buffer, "grep XYZ %s/%s > /dev/null", Path_name, TEMPFILE);
+	SAFE_MUNMAP(addr, page_sz);
 }
 
 static void cleanup(void)
 {
-	close(fildes);
-	free(dummy);
-	tst_rmdir();
+	if (dummy)
+		free(dummy);
+	if (fildes > 0)
+		SAFE_CLOSE(fildes);
 }
+
+static void setup(void)
+{
+	page_sz = getpagesize();
+
+	/* Allocate and initialize dummy string of system page size bytes */
+	dummy = SAFE_CALLOC(page_sz, sizeof(char));
+}
+
+static struct tst_test test = {
+	.setup = setup,
+	.cleanup = cleanup,
+	.needs_tmpdir = 1,
+	.test_all = run,
+	.forks_child = 1,
+};

---
base-commit: ad651beeed393121ee541e3d07990e9a3d14c0c0
change-id: 20241210-convert_mmap01-682f71beb58d

Best regards,
-- 
Ricardo B. Marliere <rbm@suse.com>


-- 
Mailing list info: https://lists.linux.it/listinfo/ltp

Re: [LTP] [PATCH v6] mmap01: Convert to new API

[Petr Vorel]

Hi Ricardo,

generally LGTM, with minor comments below (only relevant is SAFE_MSYNC()).

Reviewed-by: Petr Vorel <pvorel@suse.cz>

...
> +++ b/testcases/kernel/syscalls/mmap/mmap01.c
> @@ -1,194 +1,145 @@

> -/*
> - * Test Description:
> - *  Verify that, mmap() succeeds when used to map a file where size of the
> - *  file is not a multiple of the page size, the memory area beyond the end
> - *  of the file to the end of the page is accessible. Also, verify that
> - *  this area is all zeroed and the modifications done to this area are
> - *  not written to the file.
> +/*\
> + * [Description]
>   *
> - * Expected Result:
> - *  mmap() should succeed returning the address of the mapped region.
> - *  The memory area beyond the end of file to the end of page should be
> - *  filled with zero.
> - *  The changes beyond the end of file should not get written to the file.
> + * Verify that mmap() succeeds when used to map a file where size of the
> + * file is not a multiple of the page size, the memory area beyond the end
> + * of the file to the end of the page is accessible. Also, verify that
> + * this area is all zeroed and the modifications done to this area are
> + * not written to the file.
nit: Slightly hard to read, but I'm not able to suggest any improvement.
>   *
> - * HISTORY
> - *	07/2001 Ported by Wayne Boyer
> + * mmap() should succeed returning the address of the mapped region.
> + * The memory area beyond the end of file to the end of page should be
> + * filled with zero.
nit: FYI this new line has no effect for docparse formatting (html/pdf formatting).
If you want to have separate paragraph, it needs to be extra blank space.
I would just continue the sentence in previous paragaraph.
> + * The changes beyond the end of file should not get written to the file.
>   */

> +#include "tst_test.h"
> +
> +#define TEMPFILE "mmapfile"
> +#define STRING "hello world\n"

...

static void check_file(void)
{
	...
	for (i = 0; i < buf_len; i++)
		if (buf[i] == 'X' || buf[i] == 'Y' || buf[i] == 'Z')
			break;

	if (i == buf_len)
		tst_res(TPASS, "Functionality of mmap() successful");
very nit: IMHO that mmap() works is detectable from TPASS. I like when TPASS
describe what was the evaluation, maybe something like "pattern found in the file" ?
	else
		tst_res(TFAIL, "Specified pattern found in file");
	SAFE_CLOSE(fildes);
}

> -	page_sz = getpagesize();
> +static void run(void)
> +{
> +	pid_t pid;
> +
> +	set_file();
> +
> +	addr = SAFE_MMAP(NULL, page_sz, PROT_READ | PROT_WRITE,
> +			 MAP_FILE | MAP_SHARED, fildes, 0);
> +
> +	/*
> +	 * Check if mapped memory area beyond EOF are zeros and changes beyond
> +	 * EOF are not written to file.
> +	 */
> +	if (memcmp(&addr[file_sz], dummy, page_sz - file_sz))
> +		tst_brk(TFAIL, "mapped memory area contains invalid data");
> +
> +	/*
> +	 * Initialize memory beyond file size
> +	 */
> +	addr[file_sz] = 'X';
> +	addr[file_sz + 1] = 'Y';
> +	addr[file_sz + 2] = 'Z';
> +
> +	/*
> +	 * Synchronize the mapped memory region with the file.
> +	 */
> +	if (msync(addr, page_sz, MS_SYNC) != 0) {
> +		tst_res(TFAIL | TERRNO, "failed to synchronize mapped file");
> +		return;
I would use here SAFE_MSYNC().
> +	}

> -	/* Allocate and initialize dummy string of system page size bytes */
> -	if ((dummy = calloc(page_sz, sizeof(char))) == NULL) {
> -		tst_brkm(TFAIL, cleanup, "calloc failed (dummy)");
> +	/*
> +	 * Now, search for the pattern 'XYZ' in the temporary file.
> +	 * The pattern should not be found and the return value should be 1.
> +	 */
> +	pid = SAFE_FORK();
> +	if (!pid) {
nit: pid is not needed, how about use SAFE_FORK() directly?
if (!SAFE_FORK()) {

> +		check_file();
> +		SAFE_MUNMAP(addr, page_sz);
> +		exit(0);
>  	}
...

> +static void setup(void)
> +{
> +	page_sz = getpagesize();
> +
> +	/* Allocate and initialize dummy string of system page size bytes */
> +	dummy = SAFE_CALLOC(page_sz, sizeof(char));
nit: sizeof(char) is always guaranteed to be 1, I would use:

	dummy = SAFE_CALLOC(page_sz, 1);

The rest LGTM.

Reviewed-by: Petr Vorel <pvorel@suse.cz>

Kind regards,
Petr

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Re: [LTP] [PATCH v6] mmap01: Convert to new API

[Ricardo B. Marliere via ltp]

Hi Petr!

On 16 Dec 24 14:01, Petr Vorel wrote:
> Hi Ricardo,
> 
> generally LGTM, with minor comments below (only relevant is SAFE_MSYNC()).
> 
> Reviewed-by: Petr Vorel <pvorel@suse.cz>
> 
> ...
> > +++ b/testcases/kernel/syscalls/mmap/mmap01.c
> > @@ -1,194 +1,145 @@
> 
> > -/*
> > - * Test Description:
> > - *  Verify that, mmap() succeeds when used to map a file where size of the
> > - *  file is not a multiple of the page size, the memory area beyond the end
> > - *  of the file to the end of the page is accessible. Also, verify that
> > - *  this area is all zeroed and the modifications done to this area are
> > - *  not written to the file.
> > +/*\
> > + * [Description]
> >   *
> > - * Expected Result:
> > - *  mmap() should succeed returning the address of the mapped region.
> > - *  The memory area beyond the end of file to the end of page should be
> > - *  filled with zero.
> > - *  The changes beyond the end of file should not get written to the file.
> > + * Verify that mmap() succeeds when used to map a file where size of the
> > + * file is not a multiple of the page size, the memory area beyond the end
> > + * of the file to the end of the page is accessible. Also, verify that
> > + * this area is all zeroed and the modifications done to this area are
> > + * not written to the file.
> nit: Slightly hard to read, but I'm not able to suggest any improvement.
> >   *
> > - * HISTORY
> > - *	07/2001 Ported by Wayne Boyer
> > + * mmap() should succeed returning the address of the mapped region.
> > + * The memory area beyond the end of file to the end of page should be
> > + * filled with zero.
> nit: FYI this new line has no effect for docparse formatting (html/pdf formatting).
> If you want to have separate paragraph, it needs to be extra blank space.
> I would just continue the sentence in previous paragaraph.
> > + * The changes beyond the end of file should not get written to the file.
> >   */
> 
> > +#include "tst_test.h"
> > +
> > +#define TEMPFILE "mmapfile"
> > +#define STRING "hello world\n"
> 
> ...
> 
> static void check_file(void)
> {
> 	...
> 	for (i = 0; i < buf_len; i++)
> 		if (buf[i] == 'X' || buf[i] == 'Y' || buf[i] == 'Z')
> 			break;
> 
> 	if (i == buf_len)
> 		tst_res(TPASS, "Functionality of mmap() successful");
> very nit: IMHO that mmap() works is detectable from TPASS. I like when TPASS
> describe what was the evaluation, maybe something like "pattern found in the file" ?
> 	else
> 		tst_res(TFAIL, "Specified pattern found in file");
> 	SAFE_CLOSE(fildes);
> }
> 
> > -	page_sz = getpagesize();
> > +static void run(void)
> > +{
> > +	pid_t pid;
> > +
> > +	set_file();
> > +
> > +	addr = SAFE_MMAP(NULL, page_sz, PROT_READ | PROT_WRITE,
> > +			 MAP_FILE | MAP_SHARED, fildes, 0);
> > +
> > +	/*
> > +	 * Check if mapped memory area beyond EOF are zeros and changes beyond
> > +	 * EOF are not written to file.
> > +	 */
> > +	if (memcmp(&addr[file_sz], dummy, page_sz - file_sz))
> > +		tst_brk(TFAIL, "mapped memory area contains invalid data");
> > +
> > +	/*
> > +	 * Initialize memory beyond file size
> > +	 */
> > +	addr[file_sz] = 'X';
> > +	addr[file_sz + 1] = 'Y';
> > +	addr[file_sz + 2] = 'Z';
> > +
> > +	/*
> > +	 * Synchronize the mapped memory region with the file.
> > +	 */
> > +	if (msync(addr, page_sz, MS_SYNC) != 0) {
> > +		tst_res(TFAIL | TERRNO, "failed to synchronize mapped file");
> > +		return;
> I would use here SAFE_MSYNC().

Indeed! From now on I'll always check for SAFE_* :)

Thanks for the review, I'll push a new revision addressing your points.

-	Ricardo.


> > +	}
> 
> > -	/* Allocate and initialize dummy string of system page size bytes */
> > -	if ((dummy = calloc(page_sz, sizeof(char))) == NULL) {
> > -		tst_brkm(TFAIL, cleanup, "calloc failed (dummy)");
> > +	/*
> > +	 * Now, search for the pattern 'XYZ' in the temporary file.
> > +	 * The pattern should not be found and the return value should be 1.
> > +	 */
> > +	pid = SAFE_FORK();
> > +	if (!pid) {
> nit: pid is not needed, how about use SAFE_FORK() directly?
> if (!SAFE_FORK()) {
> 
> > +		check_file();
> > +		SAFE_MUNMAP(addr, page_sz);
> > +		exit(0);
> >  	}
> ...
> 
> > +static void setup(void)
> > +{
> > +	page_sz = getpagesize();
> > +
> > +	/* Allocate and initialize dummy string of system page size bytes */
> > +	dummy = SAFE_CALLOC(page_sz, sizeof(char));
> nit: sizeof(char) is always guaranteed to be 1, I would use:
> 
> 	dummy = SAFE_CALLOC(page_sz, 1);
> 
> The rest LGTM.
> 
> Reviewed-by: Petr Vorel <pvorel@suse.cz>
> 
> Kind regards,
> Petr

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