From: zhenwei pi <pizhenwei@bytedance.com>
To: kzak@redhat.com
Cc: util-linux@vger.kernel.org, pizhenwei@bytedance.com
Subject: [PATCH] fiemap : add fiemap misc tool
Date: Sun, 31 Mar 2019 14:35:51 +0800 [thread overview]
Message-ID: <1554014151-12743-1-git-send-email-pizhenwei@bytedance.com> (raw)
Add fiemap to dump file extent mappings. Typically we can recognize a
file is sparse or not.
For example :
#./fiemap /var/log/syslog /var/log/syslog.2.gz
File /var/log/syslog has 19 extents :
Logical Physical Length Flag
0: 0000000000000000 00000010d63a8000 0000000000001000 0000
1: 0000000000001000 00000010d63c4000 0000000000001000 0000
2: 0000000000002000 00000010d63d6000 0000000000001000 0000
3: 0000000000003000 00000010d723e000 0000000000001000 0000
4: 0000000000004000 000000076c377000 0000000000001000 0000
5: 0000000000005000 00000010d550f000 0000000000001000 0000
6: 0000000000006000 00000010d7290000 0000000000001000 0000
7: 0000000000007000 00000010d57c9000 0000000000001000 0000
8: 0000000000008000 00000010d57f5000 0000000000001000 0000
9: 0000000000009000 000000076d6b3000 0000000000001000 0000
10: 000000000000a000 00000010d558d000 0000000000001000 0000
11: 000000000000b000 00000010d77ff000 0000000000001000 0000
12: 000000000000c000 00000010d67fb000 0000000000001000 0000
13: 000000000000d000 00000010d73fc000 0000000000001000 0000
14: 000000000000e000 00000005d2bb2000 0000000000001000 0000
15: 000000000000f000 00000007705a1000 0000000000001000 0000
16: 0000000000010000 0000000c8bf10000 0000000000010000 0000
17: 0000000000020000 0000001070020000 0000000000060000 0000
18: 0000000000080000 00000011aa580000 0000000000014000 0001
File /var/log/syslog.2.gz has 1 extents :
Logical Physical Length Flag
0: 0000000000000000 0000000995c40000 0000000000023000 0001
Signed-off-by: zhenwei pi <pizhenwei@bytedance.com>
---
configure.ac | 4 +-
misc-utils/Makemodule.am | 5 ++
misc-utils/fiemap.c | 152 +++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 160 insertions(+), 1 deletion(-)
create mode 100644 misc-utils/fiemap.c
diff --git a/configure.ac b/configure.ac
index bbf07db..98c3f42 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1769,6 +1769,9 @@ UL_REQUIRES_LINUX([fincore])
UL_REQUIRES_BUILD([fincore], [libsmartcols])
AM_CONDITIONAL([BUILD_FINCORE], [test "x$build_fincore" = xyes])
+UL_BUILD_INIT([fiemap], [yes])
+AM_CONDITIONAL([BUILD_FIEMAP], [test "x$build_fiemap" = xyes])
+
UL_BUILD_INIT([fsfreeze], [check])
UL_REQUIRES_LINUX([fsfreeze])
AM_CONDITIONAL([BUILD_FSFREEZE], [test "x$build_fsfreeze" = xyes])
@@ -1820,7 +1823,6 @@ AM_CONDITIONAL([BUILD_HEXDUMP], [test "x$build_hexdump" = xyes])
UL_BUILD_INIT([rev], [yes])
AM_CONDITIONAL([BUILD_REV], [test "x$build_rev" = xyes])
-
AC_ARG_ENABLE([tunelp],
AS_HELP_STRING([--enable-tunelp], [build tunelp]),
[], [UL_DEFAULT_ENABLE([tunelp], [no])]
diff --git a/misc-utils/Makemodule.am b/misc-utils/Makemodule.am
index f56a819..8bdc6fa 100644
--- a/misc-utils/Makemodule.am
+++ b/misc-utils/Makemodule.am
@@ -228,3 +228,8 @@ hardlink_CFLAGS += $(PCRE_CFLAGS)
endif
dist_man_MANS += misc-utils/hardlink.1
endif
+
+if BUILD_FIEMAP
+usrbin_exec_PROGRAMS += fiemap
+fiemap_SOURCES = misc-utils/fiemap.c
+endif
diff --git a/misc-utils/fiemap.c b/misc-utils/fiemap.c
new file mode 100644
index 0000000..bcc807e
--- /dev/null
+++ b/misc-utils/fiemap.c
@@ -0,0 +1,152 @@
+/*
+ * Copyright (C) 2019 zhenwei pi <pizhenwei@bytedance.com>
+ *
+ * This file may be redistributed under the terms of the GNU Public
+ * License.
+ */
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <getopt.h>
+#include <sys/ioctl.h>
+#include <linux/fs.h>
+
+#include "c.h"
+#include "nls.h"
+#include "closestream.h"
+
+#ifdef FS_IOC_FIEMAP
+#include <linux/fiemap.h>
+
+static struct fiemap *read_fiemap(int fd)
+{
+ struct fiemap *fiemap;
+ int extents_size;
+
+ if ((fiemap = (struct fiemap*)malloc(sizeof(struct fiemap))) == NULL) {
+ err(EXIT_FAILURE, _("malloc"));
+ }
+
+ memset(fiemap, 0, sizeof(struct fiemap));
+
+ fiemap->fm_start = 0;
+ fiemap->fm_length = ~0;
+ fiemap->fm_flags = 0;
+ fiemap->fm_extent_count = 0;
+ fiemap->fm_mapped_extents = 0;
+
+ /* count how many extents there are */
+ if (ioctl(fd, FS_IOC_FIEMAP, fiemap) < 0) {
+ err(EXIT_FAILURE, _("fiemap ioctl() failed"));
+ }
+
+ /* read in the extents */
+ extents_size = sizeof(struct fiemap_extent) *
+ (fiemap->fm_mapped_extents);
+
+ /* resize fiemaps for all extents */
+ if ((fiemap = (struct fiemap*)realloc(fiemap,sizeof(struct fiemap) +
+ extents_size)) == NULL) {
+ err(EXIT_FAILURE, _("realloc for extents memory"));
+ }
+
+ memset(fiemap->fm_extents, 0, extents_size);
+ fiemap->fm_extent_count = fiemap->fm_mapped_extents;
+ fiemap->fm_mapped_extents = 0;
+
+ if (ioctl(fd, FS_IOC_FIEMAP, fiemap) < 0) {
+ err(EXIT_FAILURE, _("ioctl() FS_IOC_FIEMAP failed"));
+ return NULL;
+ }
+
+ return fiemap;
+}
+
+static void show_fiemap(struct fiemap *fiemap, char *filename)
+{
+ unsigned int i = 0;
+
+ printf("File %s has %d extents :\n", filename, fiemap->fm_mapped_extents);
+ printf("#\tLogical Physical Length Flag\n");
+ for (i = 0; i < fiemap->fm_mapped_extents; i++) {
+ printf("%d:\t%-16.16llx %-16.16llx %-16.16llx %-4.4x\n", i,
+ fiemap->fm_extents[i].fe_logical,
+ fiemap->fm_extents[i].fe_physical,
+ fiemap->fm_extents[i].fe_length,
+ fiemap->fm_extents[i].fe_flags);
+ }
+
+ printf("\n");
+}
+#else
+static struct fiemap *read_fiemap(int fd)
+{
+ return NULL;
+}
+
+static void show_fiemap(struct fiemap *fiemap, char *filename)
+{
+}
+#endif
+
+static void __attribute__((__noreturn__)) usage(void)
+{
+ FILE *out = stdout;
+ fputs(USAGE_HEADER, out);
+ fprintf(out, _(" %s <file>...\n"), program_invocation_short_name);
+
+ fputs(USAGE_SEPARATOR, out);
+ exit(EXIT_SUCCESS);
+}
+
+int main(int argc, char **argv)
+{
+ int c;
+ static const struct option longopts[] = {
+ { "version", no_argument, NULL, 'V' },
+ { "help", no_argument, NULL, 'h' },
+ { NULL, 0, NULL, 0 },
+ };
+
+ setlocale(LC_ALL, "");
+ bindtextdomain(PACKAGE, LOCALEDIR);
+ textdomain(PACKAGE);
+ atexit(close_stdout);
+
+ while ((c = getopt_long (argc, argv, "Vh", longopts, NULL)) != -1) {
+ switch (c) {
+ case 'V':
+ printf(UTIL_LINUX_VERSION);
+ return EXIT_SUCCESS;
+ case 'h':
+ usage();
+ default:
+ errtryhelp(EXIT_FAILURE);
+ }
+ }
+
+ if (optind == argc) {
+ warnx(_("no file specified"));
+ errtryhelp(EXIT_FAILURE);
+ }
+
+ for(; optind < argc; optind++) {
+ int fd = 0;
+
+ if ((fd = open(argv[optind], O_RDONLY)) < 0) {
+ err(EXIT_FAILURE, _("open file failed"));
+ } else {
+ struct fiemap *fiemap = NULL;
+
+ if ((fiemap = read_fiemap(fd)) != NULL) {
+ show_fiemap(fiemap, argv[optind]);
+ free(fiemap);
+ }
+ close(fd);
+ }
+ }
+
+ return 0;
+}
--
2.7.4
reply other threads:[~2019-03-31 6:35 UTC|newest]
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