Avoid running some tests if the file system does not support holes
Commit Message
Otherwise, these tests fills up the entire disk (or just run very
slowly and eventually time out).
2018-08-17 Florian Weimer <fweimer@redhat.com>
* support/support_descriptor_supports_holes.c: New file.
* support/Makefile (libsupport-routines): Add
support_descriptor_supports_holes.
* support/support.h (support_descriptor_supports_holes): Declare.
* io/tst-copy_file_range.c: Call support_descriptor_supports_holes
and stop testing if holes are not supported.
* io/test-lfs.c (do_prepare): Likewise.
* sysdeps/unix/sysv/linux/tst-fallocate-common.c (do_prepare):
Likewise.
* timezone/tst-tzset.c (create_tz_file): Likewise.
* misc/tst-preadvwritev-common.c (temp_fd_supports_holes) New
variable.
(do_prepare): Set it.
* misc/tst-preadvwritev64.c (do_test): Use temp_fd_supports_holes.
Comments
On 08/17/2018 11:07 AM, Florian Weimer wrote:
> Otherwise, these tests fills up the entire disk (or just run very
> slowly and eventually time out).
>
> 2018-08-17 Florian Weimer <fweimer@redhat.com>
>
> * support/support_descriptor_supports_holes.c: New file.
> * support/Makefile (libsupport-routines): Add
> support_descriptor_supports_holes.
> * support/support.h (support_descriptor_supports_holes): Declare.
> * io/tst-copy_file_range.c: Call support_descriptor_supports_holes
> and stop testing if holes are not supported.
> * io/test-lfs.c (do_prepare): Likewise.
> * sysdeps/unix/sysv/linux/tst-fallocate-common.c (do_prepare):
> Likewise.
> * timezone/tst-tzset.c (create_tz_file): Likewise.
> * misc/tst-preadvwritev-common.c (temp_fd_supports_holes) New
> variable.
> (do_prepare): Set it.
> * misc/tst-preadvwritev64.c (do_test): Use temp_fd_supports_holes.
>
Thanks for increasing the robustness of tests :-)
OK for master with the additional comment.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
> diff --git a/io/test-lfs.c b/io/test-lfs.c
> index f7721a5995..52120e9bca 100644
> --- a/io/test-lfs.c
> +++ b/io/test-lfs.c
> @@ -25,6 +25,7 @@
> #include <error.h>
> #include <errno.h>
> #include <sys/resource.h>
> +#include <support/check.h>
>
> /* Prototype for our test function. */
> extern void do_prepare (int argc, char *argv[]);
> @@ -70,6 +71,8 @@ do_prepare (int argc, char *argv[])
> else
> error (EXIT_FAILURE, errno, "cannot create temporary file");
> }
> + if (!support_descriptor_supports_holes (fd))
> + FAIL_UNSUPPORTED ("File %s does not support holes", name);
OK.
> add_temp_file (name);
>
> if (getrlimit64 (RLIMIT_FSIZE, &rlim) != 0)
> diff --git a/io/tst-copy_file_range.c b/io/tst-copy_file_range.c
> index 3d531a1937..e5b46f91db 100644
> --- a/io/tst-copy_file_range.c
> +++ b/io/tst-copy_file_range.c
> @@ -739,7 +739,12 @@ do_test (void)
> *p = rand () >> 24;
>
> infd = create_temp_file ("tst-copy_file_range-in-", &infile);
> - xclose (create_temp_file ("tst-copy_file_range-out-", &outfile));
> + {
> + int outfd = create_temp_file ("tst-copy_file_range-out-", &outfile);
> + if (!support_descriptor_supports_holes (outfd))
> + FAIL_UNSUPPORTED ("File %s does not support holes", outfile);
> + xclose (outfd);
> + }
OK.
>
> /* Try to find a different directory from the default input/output
> file. */
> diff --git a/misc/tst-preadvwritev-common.c b/misc/tst-preadvwritev-common.c
> index b59a3de465..4a5e53a140 100644
> --- a/misc/tst-preadvwritev-common.c
> +++ b/misc/tst-preadvwritev-common.c
> @@ -17,6 +17,7 @@
> <http://www.gnu.org/licenses/>. */
>
> #include <array_length.h>
> +#include <stdbool.h>
> #include <stdio.h>
> #include <stdint.h>
> #include <errno.h>
> @@ -26,10 +27,12 @@
>
> #include <support/check.h>
> #include <support/temp_file.h>
> +#include <support/support.h>
> #include <support/xunistd.h>
>
> static char *temp_filename;
> static int temp_fd;
> +static bool temp_fd_supports_holes;
OK.
>
> static int do_test (void);
>
> @@ -39,6 +42,7 @@ do_prepare (int argc, char **argv)
> temp_fd = create_temp_file ("tst-preadvwritev.", &temp_filename);
> if (temp_fd == -1)
> FAIL_EXIT1 ("cannot create temporary file");
> + temp_fd_supports_holes = support_descriptor_supports_holes (temp_fd);
OK.
> }
> #define PREPARE do_prepare
>
> diff --git a/misc/tst-preadvwritev64.c b/misc/tst-preadvwritev64.c
> index b718da6be5..451d03e4a8 100644
> --- a/misc/tst-preadvwritev64.c
> +++ b/misc/tst-preadvwritev64.c
> @@ -26,6 +26,12 @@ do_test (void)
>
> ret = do_test_with_offset (0);
>
> + if (!temp_fd_supports_holes)
> + {
> + puts ("warning: partial test due to lack of support for holes");
> + return ret;
> + }
OK.
> +
> /* Create a sparse file larger than 4GB to check if offset is handled
> correctly in p{write,read}v64. */
> off_t base_offset = UINT32_MAX + 2048LL;
> diff --git a/support/Makefile b/support/Makefile
> index 652d2cdf69..9063046c23 100644
> --- a/support/Makefile
> +++ b/support/Makefile
> @@ -43,6 +43,7 @@ libsupport-routines = \
> support_capture_subprocess \
> support_capture_subprocess_check \
> support_chroot \
> + support_descriptor_supports_holes \
OK.
> support_enter_mount_namespace \
> support_enter_network_namespace \
> support_format_address_family \
> diff --git a/support/support.h b/support/support.h
> index b61fe0735c..34ae6e10cd 100644
> --- a/support/support.h
> +++ b/support/support.h
> @@ -65,6 +65,12 @@ void support_write_file_string (const char *path, const char *contents);
> the result). */
> char *support_quote_blob (const void *blob, size_t length);
>
> +/* Returns non-zero if the file descriptor is a regular file on a file
> + system which supports holes (that is, seeking and writing does not
> + allocate storage for the range of zeros). FD must refer to a
> + regular file open for writing, and initially empty. */
> +int support_descriptor_supports_holes (int fd);
OK.
> +
> /* Error-checking wrapper functions which terminate the process on
> error. */
>
> diff --git a/support/support_descriptor_supports_holes.c b/support/support_descriptor_supports_holes.c
> new file mode 100644
> index 0000000000..b04498664e
> --- /dev/null
> +++ b/support/support_descriptor_supports_holes.c
> @@ -0,0 +1,80 @@
> +/* Test for file system hole support.
> + Copyright (C) 2018 Free Software Foundation, Inc.
> + This file is part of the GNU C Library.
> +
> + The GNU C Library is free software; you can redistribute it and/or
> + modify it under the terms of the GNU Lesser General Public
> + License as published by the Free Software Foundation; either
> + version 2.1 of the License, or (at your option) any later version.
> +
> + The GNU C Library 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
> + Lesser General Public License for more details.
> +
> + You should have received a copy of the GNU Lesser General Public
> + License along with the GNU C Library; if not, see
> + <http://www.gnu.org/licenses/>. */
> +
> +#include <stdbool.h>
> +#include <support.h>
> +#include <support/check.h>
> +#include <sys/stat.h>
> +#include <xunistd.h>
> +
> +int
> +support_descriptor_supports_holes (int fd)
> +{
> + enum
> + {
> + /* Write offset for the enlarged file. This value is arbitrary
> + and hopefully large enough to trigger the creation of holes.
> + We cannot use the file system block size as a reference here
> + because it is incorrect for network file systems. */
> + write_offset = 16 * 1024 * 1024,
OK. Excellent comment.
> +
> + /* Our write may add this number of additional blocks. */
> + block_headroom = 8,
> + };
> +
> + struct stat64 st;
> + xfstat (fd, &st);
> + if (!S_ISREG (st.st_mode))
> + FAIL_EXIT1 ("descriptor %d does not refer to a regular file", fd);
> + if (st.st_size != 0)
> + FAIL_EXIT1 ("descriptor %d does not refer to an empty file", fd);
> + if (st.st_blocks > block_headroom)
> + FAIL_EXIT1 ("descriptor %d refers to a pre-allocated file (%lld blocks)",
> + fd, (long long int) st.st_blocks);
> +
> + /* Write a single byte at the start of the file to compute the block
> + usage for a single byte. */
> + xlseek (fd, 0, SEEK_SET);
> + char b = '@';
> + xwrite (fd, &b, 1);
> + /* Attempt to bypass delayed allocation. */
> + TEST_COMPARE (fsync (fd), 0);
OK.
> + xfstat (fd, &st);
Needs a comment explaining why you pick block_limit to be this value. Is it
arbitrary or chosen specifically given some specific knowledge.
> + unsigned long long int block_limit = 2 * st.st_blocks + block_headroom;
> +
> + /* Write a single byte at 16 megabytes. */
> + xlseek (fd, write_offset, SEEK_SET);
OK.
> + xwrite (fd, &b, 1);
> + /* Attempt to bypass delayed allocation. */
> + TEST_COMPARE (fsync (fd), 0);
> + xfstat (fd, &st);
> + bool supports_holes = st.st_blocks <= block_limit;
OK.
> +
> + /* Also check that extending the file does not fill up holes. */
> + xftruncate (fd, 2 * write_offset);
> + /* Attempt to bypass delayed allocation. */
> + TEST_COMPARE (fsync (fd), 0);
> + xfstat (fd, &st);
> + supports_holes = supports_holes && st.st_blocks <= block_limit;
OK.
> +
> + /* Return to a zero-length file. */
> + xftruncate (fd, 0);
> + xlseek (fd, 0, SEEK_SET);
> +
> + return supports_holes;
> +}
> diff --git a/sysdeps/unix/sysv/linux/tst-fallocate-common.c b/sysdeps/unix/sysv/linux/tst-fallocate-common.c
> index a6ba403c62..bc54cf5134 100644
> --- a/sysdeps/unix/sysv/linux/tst-fallocate-common.c
> +++ b/sysdeps/unix/sysv/linux/tst-fallocate-common.c
> @@ -41,6 +41,8 @@ do_prepare (int argc, char **argv)
> temp_fd = create_temp_file ("tst-fallocate.", &temp_filename);
> if (temp_fd == -1)
> FAIL_EXIT1 ("cannot create temporary file: %m");
> + if (!support_descriptor_supports_holes (temp_fd))
> + FAIL_UNSUPPORTED ("File %s does not support holes", temp_filename);
OK.
> }
> #define PREPARE do_prepare
>
> diff --git a/timezone/tst-tzset.c b/timezone/tst-tzset.c
> index 27f986b56d..744c583f7e 100644
> --- a/timezone/tst-tzset.c
> +++ b/timezone/tst-tzset.c
> @@ -24,6 +24,7 @@
> #include <sys/resource.h>
> #include <time.h>
> #include <unistd.h>
> +#include <support/check.h>
>
> #define TIMEOUT 5
> static int do_test (void);
> @@ -38,6 +39,8 @@ create_tz_file (off64_t size)
> int fd = create_temp_file ("tst-tzset-", &path);
> if (fd < 0)
> exit (1);
> + if (!support_descriptor_supports_holes (fd))
> + FAIL_UNSUPPORTED ("File %s does not support holes", path);
OK.
>
> // Reopen for large-file support.
> close (fd);
>
@@ -25,6 +25,7 @@
#include <error.h>
#include <errno.h>
#include <sys/resource.h>
+#include <support/check.h>
/* Prototype for our test function. */
extern void do_prepare (int argc, char *argv[]);
@@ -70,6 +71,8 @@ do_prepare (int argc, char *argv[])
else
error (EXIT_FAILURE, errno, "cannot create temporary file");
}
+ if (!support_descriptor_supports_holes (fd))
+ FAIL_UNSUPPORTED ("File %s does not support holes", name);
add_temp_file (name);
if (getrlimit64 (RLIMIT_FSIZE, &rlim) != 0)
@@ -739,7 +739,12 @@ do_test (void)
*p = rand () >> 24;
infd = create_temp_file ("tst-copy_file_range-in-", &infile);
- xclose (create_temp_file ("tst-copy_file_range-out-", &outfile));
+ {
+ int outfd = create_temp_file ("tst-copy_file_range-out-", &outfile);
+ if (!support_descriptor_supports_holes (outfd))
+ FAIL_UNSUPPORTED ("File %s does not support holes", outfile);
+ xclose (outfd);
+ }
/* Try to find a different directory from the default input/output
file. */
@@ -17,6 +17,7 @@
<http://www.gnu.org/licenses/>. */
#include <array_length.h>
+#include <stdbool.h>
#include <stdio.h>
#include <stdint.h>
#include <errno.h>
@@ -26,10 +27,12 @@
#include <support/check.h>
#include <support/temp_file.h>
+#include <support/support.h>
#include <support/xunistd.h>
static char *temp_filename;
static int temp_fd;
+static bool temp_fd_supports_holes;
static int do_test (void);
@@ -39,6 +42,7 @@ do_prepare (int argc, char **argv)
temp_fd = create_temp_file ("tst-preadvwritev.", &temp_filename);
if (temp_fd == -1)
FAIL_EXIT1 ("cannot create temporary file");
+ temp_fd_supports_holes = support_descriptor_supports_holes (temp_fd);
}
#define PREPARE do_prepare
@@ -26,6 +26,12 @@ do_test (void)
ret = do_test_with_offset (0);
+ if (!temp_fd_supports_holes)
+ {
+ puts ("warning: partial test due to lack of support for holes");
+ return ret;
+ }
+
/* Create a sparse file larger than 4GB to check if offset is handled
correctly in p{write,read}v64. */
off_t base_offset = UINT32_MAX + 2048LL;
@@ -43,6 +43,7 @@ libsupport-routines = \
support_capture_subprocess \
support_capture_subprocess_check \
support_chroot \
+ support_descriptor_supports_holes \
support_enter_mount_namespace \
support_enter_network_namespace \
support_format_address_family \
@@ -65,6 +65,12 @@ void support_write_file_string (const char *path, const char *contents);
the result). */
char *support_quote_blob (const void *blob, size_t length);
+/* Returns non-zero if the file descriptor is a regular file on a file
+ system which supports holes (that is, seeking and writing does not
+ allocate storage for the range of zeros). FD must refer to a
+ regular file open for writing, and initially empty. */
+int support_descriptor_supports_holes (int fd);
+
/* Error-checking wrapper functions which terminate the process on
error. */
new file mode 100644
@@ -0,0 +1,80 @@
+/* Test for file system hole support.
+ Copyright (C) 2018 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library 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
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <http://www.gnu.org/licenses/>. */
+
+#include <stdbool.h>
+#include <support.h>
+#include <support/check.h>
+#include <sys/stat.h>
+#include <xunistd.h>
+
+int
+support_descriptor_supports_holes (int fd)
+{
+ enum
+ {
+ /* Write offset for the enlarged file. This value is arbitrary
+ and hopefully large enough to trigger the creation of holes.
+ We cannot use the file system block size as a reference here
+ because it is incorrect for network file systems. */
+ write_offset = 16 * 1024 * 1024,
+
+ /* Our write may add this number of additional blocks. */
+ block_headroom = 8,
+ };
+
+ struct stat64 st;
+ xfstat (fd, &st);
+ if (!S_ISREG (st.st_mode))
+ FAIL_EXIT1 ("descriptor %d does not refer to a regular file", fd);
+ if (st.st_size != 0)
+ FAIL_EXIT1 ("descriptor %d does not refer to an empty file", fd);
+ if (st.st_blocks > block_headroom)
+ FAIL_EXIT1 ("descriptor %d refers to a pre-allocated file (%lld blocks)",
+ fd, (long long int) st.st_blocks);
+
+ /* Write a single byte at the start of the file to compute the block
+ usage for a single byte. */
+ xlseek (fd, 0, SEEK_SET);
+ char b = '@';
+ xwrite (fd, &b, 1);
+ /* Attempt to bypass delayed allocation. */
+ TEST_COMPARE (fsync (fd), 0);
+ xfstat (fd, &st);
+ unsigned long long int block_limit = 2 * st.st_blocks + block_headroom;
+
+ /* Write a single byte at 16 megabytes. */
+ xlseek (fd, write_offset, SEEK_SET);
+ xwrite (fd, &b, 1);
+ /* Attempt to bypass delayed allocation. */
+ TEST_COMPARE (fsync (fd), 0);
+ xfstat (fd, &st);
+ bool supports_holes = st.st_blocks <= block_limit;
+
+ /* Also check that extending the file does not fill up holes. */
+ xftruncate (fd, 2 * write_offset);
+ /* Attempt to bypass delayed allocation. */
+ TEST_COMPARE (fsync (fd), 0);
+ xfstat (fd, &st);
+ supports_holes = supports_holes && st.st_blocks <= block_limit;
+
+ /* Return to a zero-length file. */
+ xftruncate (fd, 0);
+ xlseek (fd, 0, SEEK_SET);
+
+ return supports_holes;
+}
@@ -41,6 +41,8 @@ do_prepare (int argc, char **argv)
temp_fd = create_temp_file ("tst-fallocate.", &temp_filename);
if (temp_fd == -1)
FAIL_EXIT1 ("cannot create temporary file: %m");
+ if (!support_descriptor_supports_holes (temp_fd))
+ FAIL_UNSUPPORTED ("File %s does not support holes", temp_filename);
}
#define PREPARE do_prepare
@@ -24,6 +24,7 @@
#include <sys/resource.h>
#include <time.h>
#include <unistd.h>
+#include <support/check.h>
#define TIMEOUT 5
static int do_test (void);
@@ -38,6 +39,8 @@ create_tz_file (off64_t size)
int fd = create_temp_file ("tst-tzset-", &path);
if (fd < 0)
exit (1);
+ if (!support_descriptor_supports_holes (fd))
+ FAIL_UNSUPPORTED ("File %s does not support holes", path);
// Reopen for large-file support.
close (fd);