On Tue, Feb 07, 2023 at 09:01:41AM -0800, Darrick J. Wong wrote:
> From: Darrick J. Wong <djwong@xxxxxxxxxx>
>
> Create a new find(1) like utility that doesn't crash on directory tree
> changes (like find does due to bugs in its loop detector) and actually
> implements the custom xfs attribute predicates that we need for scrub
> stress tests. This program will be needed for a future patch where we
> add stress tests for scrub and repair of file metadata.
>
> Signed-off-by: Darrick J. Wong <djwong@xxxxxxxxxx>
> ---
> v24.1: apply some autoupdate love to the m4 macros
> ---
This version looks better to me, I'll merge it with a little change on
.gitignore file to filter src/xfsfind.
Reviewed-by: Zorro Lang <zlang@xxxxxxxxxx>
> configure.ac | 5 +
> include/builddefs.in | 4 +
> m4/package_libcdev.m4 | 44 +++++++
> m4/package_xfslibs.m4 | 15 +++
> src/Makefile | 10 ++
> src/xfsfind.c | 290 +++++++++++++++++++++++++++++++++++++++++++++++++
> 6 files changed, 368 insertions(+)
> create mode 100644 src/xfsfind.c
>
> diff --git a/configure.ac b/configure.ac
> index cbf8377988..e92bd6b26d 100644
> --- a/configure.ac
> +++ b/configure.ac
> @@ -66,6 +66,11 @@ AC_PACKAGE_WANT_LINUX_FS_H
> AC_PACKAGE_WANT_LIBBTRFSUTIL
>
> AC_HAVE_COPY_FILE_RANGE
> +AC_HAVE_SEEK_DATA
> +AC_HAVE_BMV_OF_SHARED
> +AC_HAVE_NFTW
> +AC_HAVE_RLIMIT_NOFILE
> +
> AC_CHECK_FUNCS([renameat2])
> AC_CHECK_FUNCS([reallocarray])
> AC_CHECK_TYPES([struct mount_attr], [], [], [[#include <linux/mount.h>]])
> diff --git a/include/builddefs.in b/include/builddefs.in
> index 6641209f81..dab10c968f 100644
> --- a/include/builddefs.in
> +++ b/include/builddefs.in
> @@ -68,6 +68,10 @@ HAVE_FIEMAP = @have_fiemap@
> HAVE_FALLOCATE = @have_fallocate@
> HAVE_COPY_FILE_RANGE = @have_copy_file_range@
> HAVE_LIBBTRFSUTIL = @have_libbtrfsutil@
> +HAVE_SEEK_DATA = @have_seek_data@
> +HAVE_NFTW = @have_nftw@
> +HAVE_BMV_OF_SHARED = @have_bmv_of_shared@
> +HAVE_RLIMIT_NOFILE = @have_rlimit_nofile@
>
> GCCFLAGS = -funsigned-char -fno-strict-aliasing -Wall
>
> diff --git a/m4/package_libcdev.m4 b/m4/package_libcdev.m4
> index 5c76c0f73e..98572aecd9 100644
> --- a/m4/package_libcdev.m4
> +++ b/m4/package_libcdev.m4
> @@ -110,3 +110,47 @@ AC_DEFUN([AC_HAVE_COPY_FILE_RANGE],
> AC_SUBST(have_copy_file_range)
> ])
>
> +# Check if we have SEEK_DATA
> +AC_DEFUN([AC_HAVE_SEEK_DATA],
> + [ AC_MSG_CHECKING([for SEEK_DATA])
> + AC_LINK_IFELSE([AC_LANG_PROGRAM([[
> +#define _GNU_SOURCE
> +#include <sys/types.h>
> +#include <unistd.h>
> + ]], [[
> + lseek(-1, 0, SEEK_DATA);
> + ]])],[have_seek_data=yes
> + AC_MSG_RESULT(yes)],[AC_MSG_RESULT(no)])
> + AC_SUBST(have_seek_data)
> + ])
> +
> +# Check if we have nftw
> +AC_DEFUN([AC_HAVE_NFTW],
> + [ AC_MSG_CHECKING([for nftw])
> + AC_LINK_IFELSE([AC_LANG_PROGRAM([[
> +#define _GNU_SOURCE
> +#include <stddef.h>
> +#include <ftw.h>
> + ]], [[
> + nftw("/", (int (*)(const char *, const struct stat *, int, struct FTW *))1, 0, 0);
> + ]])],[have_nftw=yes
> + AC_MSG_RESULT(yes)],[AC_MSG_RESULT(no)])
> + AC_SUBST(have_nftw)
> + ])
> +
> +# Check if we have RLIMIT_NOFILE
> +AC_DEFUN([AC_HAVE_RLIMIT_NOFILE],
> + [ AC_MSG_CHECKING([for RLIMIT_NOFILE])
> + AC_LINK_IFELSE([AC_LANG_PROGRAM([[
> +#define _GNU_SOURCE
> +#include <sys/time.h>
> +#include <sys/resource.h>
> + ]], [[
> + struct rlimit rlimit;
> +
> + rlimit.rlim_cur = 0;
> + getrlimit(RLIMIT_NOFILE, &rlimit);
> + ]])],[have_rlimit_nofile=yes
> + AC_MSG_RESULT(yes)],[AC_MSG_RESULT(no)])
> + AC_SUBST(have_rlimit_nofile)
> + ])
> diff --git a/m4/package_xfslibs.m4 b/m4/package_xfslibs.m4
> index 0746cd1dc5..8ef58cc064 100644
> --- a/m4/package_xfslibs.m4
> +++ b/m4/package_xfslibs.m4
> @@ -104,3 +104,18 @@ AC_DEFUN([AC_PACKAGE_NEED_XFSCTL_MACRO],
> exit 1
> ])
> ])
> +
> +# Check if we have BMV_OF_SHARED from the GETBMAPX ioctl
> +AC_DEFUN([AC_HAVE_BMV_OF_SHARED],
> + [ AC_MSG_CHECKING([for BMV_OF_SHARED])
> + AC_LINK_IFELSE([AC_LANG_PROGRAM([[
> +#define _GNU_SOURCE
> +#include <xfs/xfs.h>
> + ]], [[
> + struct getbmapx obj;
> + ioctl(-1, XFS_IOC_GETBMAPX, &obj);
> + obj.bmv_oflags |= BMV_OF_SHARED;
> + ]])],[have_bmv_of_shared=yes
> + AC_MSG_RESULT(yes)],[AC_MSG_RESULT(no)])
> + AC_SUBST(have_bmv_of_shared)
> + ])
> diff --git a/src/Makefile b/src/Makefile
> index f270015ce8..a574f7bd03 100644
> --- a/src/Makefile
> +++ b/src/Makefile
> @@ -83,6 +83,16 @@ ifeq ($(HAVE_LIBCAP), true)
> LLDLIBS += -lcap
> endif
>
> +ifeq ($(HAVE_SEEK_DATA), yes)
> + ifeq ($(HAVE_NFTW), yes)
> + ifeq ($(HAVE_BMV_OF_SHARED), yes)
> + ifeq ($(HAVE_RLIMIT_NOFILE), yes)
> + TARGETS += xfsfind
> + endif
> + endif
> + endif
> +endif
> +
> CFILES = $(TARGETS:=.c)
> LDIRT = $(TARGETS) fssum
>
> diff --git a/src/xfsfind.c b/src/xfsfind.c
> new file mode 100644
> index 0000000000..6b0a93e793
> --- /dev/null
> +++ b/src/xfsfind.c
> @@ -0,0 +1,290 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * find(1) but with special predicates for finding XFS attributes.
> + * Copyright (C) 2022 Oracle.
> + */
> +#include <sys/time.h>
> +#include <sys/resource.h>
> +#include <sys/types.h>
> +#include <stdio.h>
> +#include <unistd.h>
> +#include <ftw.h>
> +#include <linux/fs.h>
> +#include <xfs/xfs.h>
> +
> +#include "global.h"
> +
> +static int want_anyfile;
> +static int want_datafile;
> +static int want_attrfile;
> +static int want_dir;
> +static int want_regfile;
> +static int want_sharedfile;
> +static int report_errors = 1;
> +
> +static int
> +check_datafile(
> + const char *path,
> + int fd)
> +{
> + off_t off;
> +
> + off = lseek(fd, 0, SEEK_DATA);
> + if (off >= 0)
> + return 1;
> +
> + if (errno == ENXIO)
> + return 0;
> +
> + if (report_errors)
> + perror(path);
> +
> + return -1;
> +}
> +
> +static int
> +check_attrfile(
> + const char *path,
> + int fd)
> +{
> + struct fsxattr fsx;
> + int ret;
> +
> + ret = ioctl(fd, XFS_IOC_FSGETXATTR, &fsx);
> + if (ret) {
> + if (report_errors)
> + perror(path);
> + return -1;
> + }
> +
> + if (want_attrfile && (fsx.fsx_xflags & XFS_XFLAG_HASATTR))
> + return 1;
> + return 0;
> +}
> +
> +#define BMAP_NR 33
> +static struct getbmapx bmaps[BMAP_NR];
> +
> +static int
> +check_sharedfile(
> + const char *path,
> + int fd)
> +{
> + struct getbmapx *key = &bmaps[0];
> + unsigned int i;
> + int ret;
> +
> + memset(key, 0, sizeof(struct getbmapx));
> + key->bmv_length = ULLONG_MAX;
> + /* no holes and don't flush dirty pages */
> + key->bmv_iflags = BMV_IF_DELALLOC | BMV_IF_NO_HOLES;
> + key->bmv_count = BMAP_NR;
> +
> + while ((ret = ioctl(fd, XFS_IOC_GETBMAPX, bmaps)) == 0) {
> + struct getbmapx *p = &bmaps[1];
> + xfs_off_t new_off;
> +
> + for (i = 0; i < key->bmv_entries; i++, p++) {
> + if (p->bmv_oflags & BMV_OF_SHARED)
> + return 1;
> + }
> +
> + if (key->bmv_entries == 0)
> + break;
> + p = key + key->bmv_entries;
> + if (p->bmv_oflags & BMV_OF_LAST)
> + return 0;
> +
> + new_off = p->bmv_offset + p->bmv_length;
> + key->bmv_length -= new_off - key->bmv_offset;
> + key->bmv_offset = new_off;
> + }
> + if (ret < 0) {
> + if (report_errors)
> + perror(path);
> + return -1;
> + }
> +
> + return 0;
> +}
> +
> +static void
> +print_help(
> + const char *name)
> +{
> + printf("Usage: %s [OPTIONS] path\n", name);
> + printf("\n");
> + printf("Print all file paths matching any of the given predicates.\n");
> + printf("\n");
> + printf("-a Match files with xattrs.\n");
> + printf("-b Match files with data blocks.\n");
> + printf("-d Match directories.\n");
> + printf("-q Ignore errors while walking directory tree.\n");
> + printf("-r Match regular files.\n");
> + printf("-s Match files with shared blocks.\n");
> + printf("\n");
> + printf("If no matching options are given, match all files found.\n");
> +}
> +
> +static int
> +visit(
> + const char *path,
> + const struct stat *sb,
> + int typeflag,
> + struct FTW *ftwbuf)
> +{
> + int printme = 1;
> + int fd = -1;
> + int retval = FTW_CONTINUE;
> +
> + if (want_anyfile)
> + goto out;
> + if (want_regfile && typeflag == FTW_F)
> + goto out;
> + if (want_dir && typeflag == FTW_D)
> + goto out;
> +
> + /*
> + * We can only open directories and files; screen out everything else.
> + * Note that nftw lies and reports FTW_F for device files, so check the
> + * statbuf mode too.
> + */
> + if (typeflag != FTW_F && typeflag != FTW_D) {
> + printme = 0;
> + goto out;
> + }
> +
> + if (!S_ISREG(sb->st_mode) && !S_ISDIR(sb->st_mode)) {
> + printme = 0;
> + goto out;
> + }
> +
> + fd = open(path, O_RDONLY);
> + if (fd < 0) {
> + if (report_errors) {
> + perror(path);
> + return FTW_STOP;
> + }
> +
> + return FTW_CONTINUE;
> + }
> +
> + if (want_datafile && typeflag == FTW_F) {
> + int ret = check_datafile(path, fd);
> + if (ret < 0 && report_errors) {
> + printme = 0;
> + retval = FTW_STOP;
> + goto out_fd;
> + }
> +
> + if (ret == 1)
> + goto out_fd;
> + }
> +
> + if (want_attrfile) {
> + int ret = check_attrfile(path, fd);
> + if (ret < 0 && report_errors) {
> + printme = 0;
> + retval = FTW_STOP;
> + goto out_fd;
> + }
> +
> + if (ret == 1)
> + goto out_fd;
> + }
> +
> + if (want_sharedfile) {
> + int ret = check_sharedfile(path, fd);
> + if (ret < 0 && report_errors) {
> + printme = 0;
> + retval = FTW_STOP;
> + goto out_fd;
> + }
> +
> + if (ret == 1)
> + goto out_fd;
> + }
> +
> + printme = 0;
> +out_fd:
> + close(fd);
> +out:
> + if (printme)
> + printf("%s\n", path);
> + return retval;
> +}
> +
> +static void
> +handle_sigabrt(
> + int signal,
> + siginfo_t *info,
> + void *ucontext)
> +{
> + fprintf(stderr, "Signal %u, exiting.\n", signal);
> + exit(2);
> +}
> +
> +int
> +main(
> + int argc,
> + char *argv[])
> +{
> + struct rlimit rlimit;
> + struct sigaction abrt = {
> + .sa_sigaction = handle_sigabrt,
> + .sa_flags = SA_SIGINFO,
> + };
> + int c;
> + int ret;
> +
> + while ((c = getopt(argc, argv, "abdqrs")) >= 0) {
> + switch (c) {
> + case 'a': want_attrfile = 1; break;
> + case 'b': want_datafile = 1; break;
> + case 'd': want_dir = 1; break;
> + case 'q': report_errors = 0; break;
> + case 'r': want_regfile = 1; break;
> + case 's': want_sharedfile = 1; break;
> + default:
> + print_help(argv[0]);
> + return 1;
> + }
> + }
> +
> + ret = getrlimit(RLIMIT_NOFILE, &rlimit);
> + if (ret) {
> + perror("RLIMIT_NOFILE");
> + return 1;
> + }
> +
> + if (!want_attrfile && !want_datafile && !want_dir && !want_regfile &&
> + !want_sharedfile)
> + want_anyfile = 1;
> +
> + /*
> + * nftw is known to abort() if a directory it is walking disappears out
> + * from under it. Handle this with grace if the caller wants us to run
> + * quietly.
> + */
> + if (!report_errors) {
> + ret = sigaction(SIGABRT, &abrt, NULL);
> + if (ret) {
> + perror("SIGABRT handler");
> + return 1;
> + }
> + }
> +
> + for (c = optind; c < argc; c++) {
> + ret = nftw(argv[c], visit, rlimit.rlim_cur - 5,
> + FTW_ACTIONRETVAL | FTW_CHDIR | FTW_MOUNT |
> + FTW_PHYS);
> + if (ret && report_errors) {
> + perror(argv[c]);
> + break;
> + }
> + }
> +
> + if (ret)
> + return 1;
> + return 0;
> +}
>
