generic: mmap and copy file data with page overlapping
authorZorro Lang <zlang@redhat.com>
Fri, 21 May 2021 08:01:45 +0000 (16:01 +0800)
committerEryu Guan <guaneryu@gmail.com>
Sun, 23 May 2021 14:33:57 +0000 (22:33 +0800)
Mmap 2 pages of file, write 64 bytes to the first and second pages,
copy the data from the first page and then second page to the second
page offset with $pagesize - 64. Verify the data at the end.

       +-----------------------+
       |        (copy)         |
       |                       V
    +---------------+---------------+------------
    |AAAA| ........ |AAAA| ... |AAAA|AAAA|
    +---------------+---------------+------------
                       |            ^
                       |   (copy)   |
                       +------------+

This's also a regression test cover kernel commit: 4f06dd92b5d0
("fuse: fix write deadlock")

Signed-off-by: Zorro Lang <zlang@redhat.com>
Reviewed-by: Eryu Guan <guaneryu@gmail.com>
Signed-off-by: Eryu Guan <guaneryu@gmail.com>
.gitignore
src/Makefile
src/t_mmap_writev_overlap.c [new file with mode: 0644]
tests/generic/638 [new file with mode: 0755]
tests/generic/638.out [new file with mode: 0644]
tests/generic/group

index 4cc9c80..1e56d7c 100644 (file)
 /src/t_mmap_stale_pmd
 /src/t_mmap_write_ro
 /src/t_mmap_writev
 /src/t_mmap_stale_pmd
 /src/t_mmap_write_ro
 /src/t_mmap_writev
+/src/t_mmap_writev_overlap
 /src/t_mtab
 /src/t_ofd_locks
 /src/t_open_tmpfiles
 /src/t_mtab
 /src/t_ofd_locks
 /src/t_open_tmpfiles
index cc0b957..1279e4b 100644 (file)
@@ -17,7 +17,8 @@ TARGETS = dirstress fill fill2 getpagesize holes lstat64 \
        t_mmap_cow_race t_mmap_fallocate fsync-err t_mmap_write_ro \
        t_ext4_dax_journal_corruption t_ext4_dax_inline_corruption \
        t_ofd_locks t_mmap_collision mmap-write-concurrent \
        t_mmap_cow_race t_mmap_fallocate fsync-err t_mmap_write_ro \
        t_ext4_dax_journal_corruption t_ext4_dax_inline_corruption \
        t_ofd_locks t_mmap_collision mmap-write-concurrent \
-       t_get_file_time t_create_short_dirs t_create_long_dirs t_enospc
+       t_get_file_time t_create_short_dirs t_create_long_dirs t_enospc \
+       t_mmap_writev_overlap
 
 LINUX_TARGETS = xfsctl bstat t_mtab getdevicesize preallo_rw_pattern_reader \
        preallo_rw_pattern_writer ftrunc trunc fs_perms testx looptest \
 
 LINUX_TARGETS = xfsctl bstat t_mtab getdevicesize preallo_rw_pattern_reader \
        preallo_rw_pattern_writer ftrunc trunc fs_perms testx looptest \
diff --git a/src/t_mmap_writev_overlap.c b/src/t_mmap_writev_overlap.c
new file mode 100644 (file)
index 0000000..e327e73
--- /dev/null
@@ -0,0 +1,134 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (c) 2021 RedHat Inc.  All Rights Reserved.
+ *
+ * mmap a file, alloc blocks, reading&writing blocks with overlapping. For example:
+ *
+ * |<--- block --->|<--- block --->|
+ *  len             len
+ * +---------------+---------------+
+ * |AAAA| ........ |AAAA| ........ |
+ * +---------------+---------------+
+ *    |               |
+ *    |               `------------+
+ *    `-----------------------+    |
+ *                            |    |
+ *                            V    V
+ * +---------------+---------------+----+
+ * |AAAA| ........ |AAAA| ... |AAAA|AAAA|
+ * +---------------+---------------+----+
+ */
+#include <sys/types.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <sys/mman.h>
+#include <string.h>
+#include <sys/uio.h>
+#include <unistd.h>
+
+void usage(char *progname)
+{
+       fprintf(stderr, "usage: %s [-b blocksize ] [-c count] [-l length] filename\n"
+               "\tmmap $count * $blocksize bytes memory, pwritev $length bytes in each block. blocksize=4096, count=2, length=12 by default.\n"
+                "e.g: %s -b 4096 -c 2 -l 12 filename\n",
+               progname, progname);
+        exit(1);
+}
+
+int main(int argc, char **argv)
+{
+       char *filename = NULL;
+       size_t bsize = 4096;
+       size_t count = 2;
+       size_t length = 12;
+       int fd, i, c;
+       void *base;
+       char *buf, *cmp_buf;
+       struct iovec *iov;
+       int ret = 0;
+
+       while ((c = getopt(argc, argv, "b:l:c:")) != -1) {
+               char *endp;
+
+               switch (c) {
+               case 'b':
+                       bsize = strtoul(optarg, &endp, 0);
+                       break;
+               case 'c':
+                       count = strtoul(optarg, &endp, 0);
+                       break;
+               case 'l':
+                       length = strtoul(optarg, &endp, 0);
+                       break;
+               default:
+                       usage(argv[0]);
+               }
+       }
+
+       if (optind == argc - 1)
+               filename = argv[optind];
+       else
+               usage(argv[0]);
+
+       if (length >= bsize) {
+               printf("-l length must be less than -b blocksize\n");
+               usage(argv[0]);
+       }
+
+       fd = open(filename, O_RDWR);
+       if (fd == -1) {
+               fprintf(stderr, "open %s failed:%s\n", filename, strerror(errno));
+               exit(1);
+       }
+       base = mmap(NULL, bsize * count, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0);
+       if (base == MAP_FAILED) {
+               fprintf(stderr, "mmap failed %s\n", strerror(errno));
+               exit(1);
+       }
+
+       /* Write each of blocks */
+       buf = malloc(length);
+       memset(buf, 0xAA, length);
+       for (i=0; i<count; i++) {
+               ret = pwrite(fd, buf, length, i * bsize);
+               if (ret == -1) {
+                       fprintf(stderr, "pwrite failed %s\n", strerror(errno));
+                       exit(1);
+               }
+       }
+
+       /* Copy from the beginning of each blocks ... */
+       iov = malloc(sizeof(struct iovec) * count);
+       for (i=0; i<count; i++) {
+               iov[i].iov_base = base + i * bsize;
+               iov[i].iov_len  = length;
+       }
+       /* ... Write to the last block with offset ($bsize - $length) */
+       ret = pwritev(fd, iov, count, bsize * count - length);
+       if (ret == -1) {
+               fprintf(stderr, "pwritev failed %s\n", strerror(errno));
+               exit(1);
+       }
+
+       /* Verify data */
+       cmp_buf = malloc(length);
+       for (i=0; i<count; i++) {
+               ret = pread(fd, cmp_buf, length, bsize * count + (i - 1) * length);
+               if (ret == -1) {
+                       fprintf(stderr, "pread failed %s\n", strerror(errno));
+                       exit(1);
+               }
+               if (memcmp(buf, cmp_buf, length))
+                       printf("Find corruption\n");
+       }
+
+       munmap(base, bsize * count);
+       free(buf);
+       free(cmp_buf);
+       free(iov);
+       close(fd);
+
+       return 0;
+}
diff --git a/tests/generic/638 b/tests/generic/638
new file mode 100755 (executable)
index 0000000..31c0c86
--- /dev/null
@@ -0,0 +1,57 @@
+#! /bin/bash
+# SPDX-License-Identifier: GPL-2.0
+# Copyright (c) 2021 Red Hat Inc.  All Rights Reserved.
+#
+# FS QA Test 638
+#
+# This case mmaps several pages of a file, alloc pages, copy data with pages
+# overlapping, e.g:
+#       +-----------------------+
+#       |        (copy)         |
+#       |                       V
+#    +---------------+---------------+------------
+#    |AAAA| ........ |AAAA| ... |AAAA|AAAA|
+#    +---------------+---------------+------------
+#                       |            ^
+#                       |   (copy)   |
+#                       +------------+
+#
+# This's a regression test cover kernel commit:
+#   4f06dd92b5d0 ("fuse: fix write deadlock")
+#
+seq=`basename $0`
+seqres=$RESULT_DIR/$seq
+echo "QA output created by $seq"
+
+here=`pwd`
+tmp=/tmp/$$
+status=1       # failure is the default!
+trap "_cleanup; exit \$status" 0 1 2 3 15
+
+_cleanup()
+{
+       cd /
+       rm -f $tmp.*
+}
+
+# get standard environment, filters and checks
+. ./common/rc
+. ./common/filter
+
+# remove previous $seqres.full before test
+rm -f $seqres.full
+
+# real QA test starts here
+_supported_fs generic
+_require_test
+_require_test_program "t_mmap_writev_overlap"
+
+pagesize=`getconf PAGE_SIZE`
+testfile=$TEST_DIR/mmap-writev-overlap
+$XFS_IO_PROG -f -c "truncate 0" $testfile
+$here/src/t_mmap_writev_overlap -b $pagesize -c 2 -l 64 $testfile
+
+echo "Silence is golden"
+# success, all done
+status=0
+exit
diff --git a/tests/generic/638.out b/tests/generic/638.out
new file mode 100644 (file)
index 0000000..3113b1e
--- /dev/null
@@ -0,0 +1,2 @@
+QA output created by 638
+Silence is golden
index 6cdbd66..9a636b2 100644 (file)
 635 auto quick atime bigtime shutdown
 636 auto quick swap
 637 auto quick dir
 635 auto quick atime bigtime shutdown
 636 auto quick swap
 637 auto quick dir
+638 auto quick rw