Adding ZTS test for O_APPEND

Commit 63b18e4 fixed an issue in zpl_aio_write() to make sure that
kiocb->ki_pos was updated correctly when opening a file with O_APPEND.
Adding a test to verify O_APPEND functionality with lseek can make
sure that all other distros/kernel versions also have the correct
behavior.

Also moved the threadappends_001_pos test into this append test
directory in functional ZTS directory. This way the two append tests
are together for organization purposes.

Reviewed-by: Brian Behlendorf <[email protected]>
Signed-off-by: Brian Atkinson <[email protected]>
Closes #13424 

3 files changed, 209 insertions, 2 deletions

diff --git a/tests/zfs-tests/cmd/.gitignore b/tests/zfs-tests/cmd/.gitignore
index 9de5687d6..1830cab76 100644
--- a/tests/zfs-tests/cmd/.gitignore
+++ b/tests/zfs-tests/cmd/.gitignore
@@ -4,6 +4,7 @@
 /devname2devid
 /dir_rd_update
 /draid
+/file_append
 /file_check
 /file_trunc
 /file_write
diff --git a/tests/zfs-tests/cmd/Makefile.am b/tests/zfs-tests/cmd/Makefile.am
index b5609b523..71edd4939 100644
--- a/tests/zfs-tests/cmd/Makefile.am
+++ b/tests/zfs-tests/cmd/Makefile.am
@@ -41,9 +41,9 @@ scripts_zfs_tests_bin_PROGRAMS += %D%/draid
 	libnvpair.la
 %C%_draid_LDADD += $(ZLIB_LIBS)
 
-
 EXTRA_DIST += $(addprefix %D%/,file/file_common.h)
-scripts_zfs_tests_bin_PROGRAMS += %D%/file_check %D%/file_trunc %D%/file_write %D%/largest_file %D%/randwritecomp
+scripts_zfs_tests_bin_PROGRAMS += %D%/file_append %D%/file_check %D%/file_trunc %D%/file_write %D%/largest_file %D%/randwritecomp
+%C%_file_append_SOURCES   = %D%/file/file_append.c
 %C%_file_check_SOURCES    = %D%/file/file_check.c
 %C%_file_trunc_SOURCES    = %D%/file/file_trunc.c
 %C%_file_write_SOURCES    = %D%/file/file_write.c
diff --git a/tests/zfs-tests/cmd/file/file_append.c b/tests/zfs-tests/cmd/file/file_append.c
new file mode 100644
index 000000000..32433e4fa
--- /dev/null
+++ b/tests/zfs-tests/cmd/file/file_append.c
@@ -0,0 +1,206 @@
+/*
+ * CDDL HEADER START
+ *
+ * The contents of this file are subject to the terms of the
+ * Common Development and Distribution License (the "License").
+ * You may not use this file except in compliance with the License.
+ *
+ * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
+ * or http://www.opensolaris.org/os/licensing.
+ * See the License for the specific language governing permissions
+ * and limitations under the License.
+ *
+ * When distributing Covered Code, include this CDDL HEADER in each
+ * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
+ * If applicable, add the following below this CDDL HEADER, with the
+ * fields enclosed by brackets "[]" replaced with your own identifying
+ * information: Portions Copyright [yyyy] [name of copyright owner]
+ *
+ * CDDL HEADER END
+ */
+
+/*
+ * Copyright (c) 2022 by Triad National Security, LLC
+ */
+
+#include "file_common.h"
+#include <unistd.h>
+#include <sys/sysmacros.h>
+
+static char *filename = NULL;
+static int expected_offset = -1;
+static int blocksize = 131072; /* 128KiB */
+static int numblocks = 8;
+static const char *execname = "file_append";
+static int use_odirect = 0;
+
+static void
+usage(void)
+{
+	(void) fprintf(stderr,
+	    "usage %s -f filename -e expected_offset [-b blocksize] \n"
+	    "         [-n numblocks] [-d use_odirect] [-h help]\n"
+	    "\n"
+	    "Opens a file using O_APPEND and writes numblocks blocksize\n"
+	    "blocks to filename.\n"
+	    "Checks if expected_offst == lseek(fd, 0, SEEK_CUR)).\n"
+	    "\n"
+	    "    filename:         File to open with O_APPEND and write to.\n"
+	    "    expected_offset:  Expected file offset after writing\n"
+	    "                      blocksize numblocks to filename\n"
+	    "    blocksize:        Size of each block to writei (must be at\n"
+	    "                      least >= 512). If using use_odirect (-d)\n"
+	    "                      must be a mutltiple of _SC_PAGE_SIZE\n"
+	    "    numblocks:        Total number of blocksized blocks to\n"
+	    "                      write.\n"
+	    "    use_odirect:      Open file using O_DIRECT.\n"
+	    "    help:             Print usage information and exit.\n"
+	    "\n"
+	    "    Required parameters:\n"
+	    "    filename\n"
+	    "    expected_offset\n"
+	    "\n"
+	    "    Default values:\n"
+	    "    blocksize   -> 131072 (128 KiB)\n"
+	    "    numblocks   -> 8\n"
+	    "    use_odirect -> False\n",
+	    execname);
+	(void) exit(1);
+}
+
+static void
+parse_options(int argc, char *argv[])
+{
+	int c;
+	int errflag = 0;
+	extern char *optarg;
+	extern int optind, optopt;
+
+	while ((c = getopt(argc, argv, "b:de:f:hn:")) != -1) {
+		switch (c) {
+			case 'b':
+				blocksize = atoi(optarg);
+				break;
+			case 'd':
+				use_odirect = 1;
+				break;
+			case 'e':
+				expected_offset = atoi(optarg);
+				break;
+			case 'f':
+				filename = optarg;
+				break;
+			case 'h':
+				(void) usage();
+				break;
+			case 'n':
+				numblocks = atoi(optarg);
+				break;
+			case ':':
+				(void) fprintf(stderr,
+				    "Option -%c requires an operand\n",
+				    optopt);
+				errflag++;
+				break;
+			case '?':
+			default:
+				(void) fprintf(stderr,
+				    "Unrecognized option: -%c\n", optopt);
+				errflag++;
+				break;
+		}
+	}
+
+	if (errflag)
+		(void) usage();
+
+	if (use_odirect && ((blocksize % sysconf(_SC_PAGE_SIZE)) != 0)) {
+		(void) fprintf(stderr,
+		    "blocksize parameter invalid when using O_DIRECT.\n");
+		(void) usage();
+	}
+
+	if (blocksize < 512 || expected_offset < 0 || filename == NULL ||
+	    numblocks <= 0) {
+		(void) fprintf(stderr,
+		    "Required parameters(s) missing or invalid value for "
+		    "parameter.\n");
+		(void) usage();
+	}
+}
+
+int
+main(int argc, char *argv[])
+{
+	int		err;
+	const char	*datapattern = "0xf00ba3";
+	int		fd = -1;
+	int		fd_flags = O_WRONLY | O_CREAT | O_APPEND;
+	int		buf_offset = 0;
+	char		*buf;
+
+	parse_options(argc, argv);
+
+	if (use_odirect)
+		fd_flags |= O_DIRECT;
+
+	fd = open(filename, fd_flags, 0666);
+	if (fd == -1) {
+		(void) fprintf(stderr, "%s: %s: ", execname, filename);
+		perror("open");
+		(void) exit(2);
+	}
+
+	err = posix_memalign((void **)&buf, sysconf(_SC_PAGE_SIZE),
+	    blocksize);
+
+	if (err != 0) {
+		(void) fprintf(stderr,
+		    "%s: %s\n", execname, strerror(err));
+		(void) exit(2);
+	}
+
+	/* Putting known data pattern in buffer */
+	int left = blocksize;
+	while (left) {
+		size_t amt = MIN(strlen(datapattern), left);
+		memcpy(&buf[buf_offset], datapattern, amt);
+		buf_offset += amt;
+		left -= amt;
+	}
+
+	for (int i = 0; i < numblocks; i++) {
+		int wrote = write(fd, buf, blocksize);
+
+		if (wrote != blocksize) {
+			if (wrote < 0) {
+				perror("write");
+			} else {
+				(void) fprintf(stderr,
+				    "%s: unexpected short write, wrote %d "
+				    "byte, expected %d\n", execname, wrote,
+				    blocksize);
+			}
+			(void) exit(2);
+		}
+	}
+
+	/* Getting current file offset */
+	off_t off = lseek(fd, 0, SEEK_CUR);
+
+	if (off == -1) {
+		perror("output seek");
+		(void) exit(2);
+	} else if (off != expected_offset) {
+		(void) fprintf(stderr,
+		    "%s: expected offset %d but current offset in %s is set "
+		    "to %ld\n", execname, expected_offset, filename,
+		    (long int)off);
+		(void) exit(2);
+	}
+
+	(void) close(fd);
+	free(buf);
+
+	return (0);
+}