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bug#6131: [PATCH]: fiemap support for efficient sparse file copy
|
From: |
Jim Meyering |
|
Subject: |
bug#6131: [PATCH]: fiemap support for efficient sparse file copy |
|
Date: |
Thu, 27 May 2010 12:30:58 +0200 |
jeff.liu wrote:
> This is the revised version, it fixed the fiemap-start offset calculation
> approach to remove it out
> of the 'for (i = 0; i < fiemap->fm_mapped_extents; i++)' loop.
Hi Jeff,
I've included below the state of my local changes.
Unfortunately, with that 5-patch series, there is always a test failure
on F13/ext4. Maybe someone who knows more about extents can provide an
explanation?
Here's a small example to demonstrate:
Create a file with many extents:
perl -e 'BEGIN { $n = 19 * 1024; *F = *STDOUT }' \
-e 'for (1..100) { sysseek (*F, $n, 1)' \
-e '&& syswrite (*F, "."x$n) or die "$!"}' > j1
Using the patched "cp", repeat the following 10 or 20 times:
./cp --sparse=always j1 j2; sync
filefrag -v j1 | awk '/^ / {print $1,$2}' > ff1 || fail=1
filefrag -v j2 | awk '/^ / {print $1,$2}' > ff2 || fail=1
diff -u ff1 ff2 || fail=1
Usually there is no diff output, but occasionally it'll print this:
[hmm... today it consistently prints these differences every other time.]
$ diff -u ff1 ff2 || fail=1
--- ff1 2010-05-22 18:42:26.943501382 +0200
+++ ff2 2010-05-22 18:42:27.020876155 +0200
@@ -53,49 +53,50 @@ ext logical
51 489
52 498
53 508
-54 517
-55 527
-56 536
-57 546
-58 555
-59 565
-60 574
-61 584
-62 593
-63 603
-64 612
-65 622
-66 631
-67 641
-68 650
-69 660
-70 669
-71 679
-72 688
-73 698
-74 707
-75 717
-76 726
-77 736
-78 745
-79 755
-80 764
-81 774
-82 783
-83 793
-84 802
-85 812
-86 821
-87 831
-88 840
-89 850
-90 859
-91 869
-92 878
-93 888
-94 897
-95 907
-96 916
-97 926
-98 935
-99 945
+54 512
+55 517
+56 527
+57 536
+58 546
+59 555
+60 565
+61 574
+62 584
+63 593
+64 603
+65 612
+66 622
+67 631
+68 641
+69 650
+70 660
+71 669
+72 679
+73 688
+74 698
+75 707
+76 717
+77 726
+78 736
+79 745
+80 755
+81 764
+82 774
+83 783
+84 793
+85 802
+86 812
+87 821
+88 831
+89 840
+90 850
+91 859
+92 869
+93 878
+94 888
+95 897
+96 907
+97 916
+98 926
+99 935
+100 945
>From 2ef44bcb0bbb38cca738aa90e067caee312da939 Mon Sep 17 00:00:00 2001
From: Jie Liu <address@hidden>
Date: Thu, 13 May 2010 22:09:30 +0800
Subject: [PATCH 1/5] cp: Add FIEMAP support for efficient sparse file copy
* src/fiemap.h: Add fiemap.h for fiemap ioctl(2) support.
Copied from linux's include/linux/fiemap.h, with minor formatting changes.
* src/copy.c (copy_reg): Now, when `cp' invoked with --sparse=[WHEN] option, we
will try to do FIEMAP-copy if the underlaying file system support it, fall back
to a normal copy if it fails.
---
src/copy.c | 159 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
src/fiemap.h | 102 +++++++++++++++++++++++++++++++++++++
2 files changed, 261 insertions(+), 0 deletions(-)
create mode 100644 src/fiemap.h
diff --git a/src/copy.c b/src/copy.c
index c16cef6..0e54729 100644
--- a/src/copy.c
+++ b/src/copy.c
@@ -63,6 +63,10 @@
#include <sys/ioctl.h>
+#ifndef HAVE_FIEMAP
+# include "fiemap.h"
+#endif
+
#ifndef HAVE_FCHOWN
# define HAVE_FCHOWN false
# define fchown(fd, uid, gid) (-1)
@@ -149,6 +153,141 @@ clone_file (int dest_fd, int src_fd)
#endif
}
+#ifdef __linux__
+# ifndef FS_IOC_FIEMAP
+# define FS_IOC_FIEMAP _IOWR ('f', 11, struct fiemap)
+# endif
+/* Perform FIEMAP(available in mainline 2.6.27) copy if possible.
+ Call ioctl(2) with FS_IOC_FIEMAP to efficiently map file allocation
+ excepts holes. So the overhead to deal with holes with lseek(2) in
+ normal copy could be saved. This would result in much faster backups
+ for any kind of sparse file. */
+static bool
+fiemap_copy_ok (int src_fd, int dest_fd, size_t buf_size,
+ off_t src_total_size, char const *src_name,
+ char const *dst_name, bool *normal_copy_required)
+{
+ bool fail = false;
+ bool last = false;
+ char fiemap_buf[4096];
+ struct fiemap *fiemap = (struct fiemap *)fiemap_buf;
+ struct fiemap_extent *fm_ext = &fiemap->fm_extents[0];
+ uint32_t count = (sizeof (fiemap_buf) - sizeof (*fiemap)) /
+ sizeof (struct fiemap_extent);
+ off_t last_ext_logical = 0;
+ uint64_t last_ext_len = 0;
+ uint64_t last_read_size = 0;
+ unsigned int i = 0;
+
+ /* This is required at least to initialize fiemap->fm_start,
+ but also serves (in May 2010) to appease valgrind, which
+ appears not to know the semantics of the FIEMAP ioctl. */
+ memset (fiemap_buf, 0, sizeof fiemap_buf);
+
+ do
+ {
+ fiemap->fm_length = FIEMAP_MAX_OFFSET;
+ fiemap->fm_extent_count = count;
+
+ /* When ioctl(2) fails, fall back to the normal copy only if it
+ is the first time we met. */
+ if (ioctl (src_fd, FS_IOC_FIEMAP, fiemap) < 0)
+ {
+ /* If `i > 0', then at least one ioctl(2) has been performed before.
*/
+ if (i == 0)
+ *normal_copy_required = true;
+ return false;
+ }
+
+ /* If 0 extents are returned, then more ioctls are not needed. */
+ if (fiemap->fm_mapped_extents == 0)
+ break;
+
+ for (i = 0; i < fiemap->fm_mapped_extents; i++)
+ {
+ assert (fm_ext[i].fe_logical <= OFF_T_MAX);
+
+ off_t ext_logical = fm_ext[i].fe_logical;
+ uint64_t ext_len = fm_ext[i].fe_length;
+
+ if (lseek (src_fd, ext_logical, SEEK_SET) < 0LL)
+ {
+ error (0, errno, _("cannot lseek %s"), quote (src_name));
+ return fail;
+ }
+
+ if (lseek (dest_fd, ext_logical, SEEK_SET) < 0LL)
+ {
+ error (0, errno, _("cannot lseek %s"), quote (dst_name));
+ return fail;
+ }
+
+ if (fm_ext[i].fe_flags & FIEMAP_EXTENT_LAST)
+ {
+ last_ext_logical = ext_logical;
+ last_ext_len = ext_len;
+ last = true;
+ }
+
+ while (0 < ext_len)
+ {
+ char buf[buf_size];
+
+ /* Avoid reading into the holes if the left extent
+ length is shorter than the buffer size. */
+ if (ext_len < buf_size)
+ buf_size = ext_len;
+
+ ssize_t n_read = read (src_fd, buf, buf_size);
+ if (n_read < 0)
+ {
+#ifdef EINTR
+ if (errno == EINTR)
+ continue;
+#endif
+ error (0, errno, _("reading %s"), quote (src_name));
+ return fail;
+ }
+
+ if (n_read == 0)
+ {
+ /* Figure out how many bytes read from the last extent. */
+ last_read_size = last_ext_len - ext_len;
+ break;
+ }
+
+ if (full_write (dest_fd, buf, n_read) != n_read)
+ {
+ error (0, errno, _("writing %s"), quote (dst_name));
+ return fail;
+ }
+
+ ext_len -= n_read;
+ }
+ }
+
+ fiemap->fm_start = fm_ext[i - 1].fe_logical + fm_ext[i - 1].fe_length;
+
+ } while (! last);
+
+ /* If a file ends up with holes, the sum of the last extent logical offset
+ and the read-returned size will be shorter than the actual size of the
+ file. Use ftruncate to extend the length of the destination file. */
+ if (last_ext_logical + last_read_size < src_total_size)
+ {
+ if (ftruncate (dest_fd, src_total_size) < 0)
+ {
+ error (0, errno, _("extending %s"), quote (dst_name));
+ return fail;
+ }
+ }
+
+ return ! fail;
+}
+#else
+static bool fiemap_copy_ok (ignored) { errno == ENOTSUP; return false; }
+#endif
+
/* FIXME: describe */
/* FIXME: rewrite this to use a hash table so we avoid the quadratic
performance hit that's probably noticeable only on trees deeper
@@ -679,6 +818,25 @@ copy_reg (char const *src_name, char const *dst_name,
#endif
}
+ if (make_holes)
+ {
+ bool require_normal_copy = false;
+ /* Perform efficient FIEMAP copy for sparse files, fall back to the
+ standard copy only if the ioctl(2) fails. */
+ if (fiemap_copy_ok (source_desc, dest_desc, buf_size,
+ src_open_sb.st_size, src_name,
+ dst_name, &require_normal_copy))
+ goto preserve_metadata;
+ else
+ {
+ if (! require_normal_copy)
+ {
+ return_val = false;
+ goto close_src_and_dst_desc;
+ }
+ }
+ }
+
/* If not making a sparse file, try to use a more-efficient
buffer size. */
if (! make_holes)
@@ -807,6 +965,7 @@ copy_reg (char const *src_name, char const *dst_name,
}
}
+preserve_metadata:
if (x->preserve_timestamps)
{
struct timespec timespec[2];
diff --git a/src/fiemap.h b/src/fiemap.h
new file mode 100644
index 0000000..d33293b
--- /dev/null
+++ b/src/fiemap.h
@@ -0,0 +1,102 @@
+/* FS_IOC_FIEMAP ioctl infrastructure.
+ Some portions copyright (C) 2007 Cluster File Systems, Inc
+ Authors: Mark Fasheh <address@hidden>
+ Kalpak Shah <address@hidden>
+ Andreas Dilger <address@hidden>. */
+
+/* Copy from kernel, modified to respect GNU code style by Jie Liu. */
+
+#ifndef _LINUX_FIEMAP_H
+# define _LINUX_FIEMAP_H
+
+# include <linux/types.h>
+
+struct fiemap_extent
+{
+ /* Logical offset in bytes for the start of the extent
+ from the beginning of the file. */
+ uint64_t fe_logical;
+
+ /* Physical offset in bytes for the start of the extent
+ from the beginning of the disk. */
+ uint64_t fe_physical;
+
+ /* Length in bytes for this extent. */
+ uint64_t fe_length;
+
+ uint64_t fe_reserved64[2];
+
+ /* FIEMAP_EXTENT_* flags for this extent. */
+ uint32_t fe_flags;
+
+ uint32_t fe_reserved[3];
+};
+
+struct fiemap
+{
+ /* Logical offset(inclusive) at which to start mapping(in). */
+ uint64_t fm_start;
+
+ /* Logical length of mapping which userspace wants(in). */
+ uint64_t fm_length;
+
+ /* FIEMAP_FLAG_* flags for request(in/out). */
+ uint32_t fm_flags;
+
+ /* Number of extents that were mapped(out). */
+ uint32_t fm_mapped_extents;
+
+ /* Size of fm_extents array(in). */
+ uint32_t fm_extent_count;
+
+ uint32_t fm_reserved;
+
+ /* Array of mapped extents(out). */
+ struct fiemap_extent fm_extents[0];
+};
+
+/* The maximum offset can be mapped for a file. */
+# define FIEMAP_MAX_OFFSET (~0ULL)
+
+/* Sync file data before map. */
+# define FIEMAP_FLAG_SYNC 0x00000001
+
+/* Map extented attribute tree. */
+# define FIEMAP_FLAG_XATTR 0x00000002
+
+# define FIEMAP_FLAGS_COMPAT (FIEMAP_FLAG_SYNC | FIEMAP_FLAG_XATTR)
+
+/* Last extent in file. */
+# define FIEMAP_EXTENT_LAST 0x00000001
+
+/* Data location unknown. */
+# define FIEMAP_EXTENT_UNKNOWN 0x00000002
+
+/* Location still pending, Sets EXTENT_UNKNOWN. */
+# define FIEMAP_EXTENT_DELALLOC 0x00000004
+
+/* Data can not be read while fs is unmounted. */
+# define FIEMAP_EXTENT_ENCODED 0x00000008
+
+/* Data is encrypted by fs. Sets EXTENT_NO_BYPASS. */
+# define FIEMAP_EXTENT_DATA_ENCRYPTED 0x00000080
+
+/* Extent offsets may not be block aligned. */
+# define FIEMAP_EXTENT_NOT_ALIGNED 0x00000100
+
+/* Data mixed with metadata. Sets EXTENT_NOT_ALIGNED. */
+# define FIEMAP_EXTENT_DATA_INLINE 0x00000200
+
+/* Multiple files in block. Set EXTENT_NOT_ALIGNED. */
+# define FIEMAP_EXTENT_DATA_TAIL 0x00000400
+
+/* Space allocated, but not data (i.e. zero). */
+# define FIEMAP_EXTENT_UNWRITTEN 0x00000800
+
+/* File does not natively support extents. Result merged for efficiency. */
+# define FIEMAP_EXTENT_MERGED 0x00001000
+
+/* Space shared with other files. */
+# define FIEMAP_EXTENT_SHARED 0x00002000
+
+#endif
--
1.7.1.348.gb26ba
>From 260b5b89e33da2b9a5ea5bcd9dba874f503d2937 Mon Sep 17 00:00:00 2001
From: Jie Liu <address@hidden>
Date: Thu, 13 May 2010 22:17:53 +0800
Subject: [PATCH 2/5] tests: add a new test for FIEMAP-copy
* tests/cp/sparse-fiemap: Add a new test for FIEMAP-copy against a
loopbacked ext4 partition.
* tests/Makefile.am (sparse-fiemap): Reference the new test.
---
tests/Makefile.am | 1 +
tests/cp/sparse-fiemap | 56 ++++++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 57 insertions(+), 0 deletions(-)
create mode 100755 tests/cp/sparse-fiemap
diff --git a/tests/Makefile.am b/tests/Makefile.am
index c458574..f7840c8 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -25,6 +25,7 @@ root_tests = \
cp/special-bits \
cp/cp-mv-enotsup-xattr \
cp/capability \
+ cp/sparse-fiemap \
dd/skip-seek-past-dev \
install/install-C-root \
ls/capability \
diff --git a/tests/cp/sparse-fiemap b/tests/cp/sparse-fiemap
new file mode 100755
index 0000000..945c94b
--- /dev/null
+++ b/tests/cp/sparse-fiemap
@@ -0,0 +1,56 @@
+#!/bin/sh
+# Test cp --sparse=always through fiemap copy
+
+# Copyright (C) 2006-2010 Free Software Foundation, Inc.
+
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+
+# This program 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 General Public License for more details.
+
+# You should have received a copy of the GNU General Public License
+# along with this program. If not, see <http://www.gnu.org/licenses/>.
+
+if test "$VERBOSE" = yes; then
+ set -x
+ cp --version
+fi
+
+. $srcdir/test-lib.sh
+require_root_
+
+cwd=`pwd`
+cleanup_() { cd /; umount "$cwd/mnt"; }
+
+skip=0
+# Create an ext4 loopback file system
+dd if=/dev/zero of=blob bs=8192 count=1000 || skip=1
+mkdir mnt
+mkfs -t ext4 -F blob ||
+ skip_test_ "failed to create ext4 file system"
+mount -oloop blob mnt || skip=1
+echo test > mnt/f || skip=1
+test -s mnt/f || skip=1
+
+test $skip = 1 &&
+ skip_test_ "insufficient mount/ext4 support"
+
+# Create a 1TiB sparse file
+dd if=/dev/zero of=mnt/sparse bs=1k count=1 seek=1G || framework_failure
+
+cd mnt || fail=1
+
+# It takes many minutes to copy this sparse file using the old method.
+# By contrast, it takes far less than 1 second using FIEMAP-copy.
+timeout 10 cp --sparse=always sparse fiemap || fail=1
+
+# Ensure that the sparse file copied through fiemap has the same size
+# in bytes as the original.
+test $(stat --printf %s sparse) = $(stat --printf %s fiemap) || fail=1
+
+Exit $fail
--
1.7.1.348.gb26ba
>From 738031aed78b6323969f799d3d5fbf19e0cfc91a Mon Sep 17 00:00:00 2001
From: Jim Meyering <address@hidden>
Date: Fri, 21 May 2010 18:28:42 +0200
Subject: [PATCH 3/5] tests: exercise more of the new FIEMAP copying code
* tests/cp/sparse-fiemap: Ensure that a file with many extents (more
than fit in copy.c's internal 4KiB buffer) is copied properly.
---
tests/cp/sparse-fiemap | 38 ++++++++++++++++++++++++++++++++++++++
1 files changed, 38 insertions(+), 0 deletions(-)
diff --git a/tests/cp/sparse-fiemap b/tests/cp/sparse-fiemap
index 945c94b..b1643be 100755
--- a/tests/cp/sparse-fiemap
+++ b/tests/cp/sparse-fiemap
@@ -53,4 +53,42 @@ timeout 10 cp --sparse=always sparse fiemap || fail=1
# in bytes as the original.
test $(stat --printf %s sparse) = $(stat --printf %s fiemap) || fail=1
+# =================================================
+# Ensure that we exercise the FIEMAP-copying code enough
+# to provoke at least two iterations of the do...while loop
+# in which it calls ioctl (fd, FS_IOC_FIEMAP,...
+# This also verifies that non-trivial extents are preserved.
+
+$PERL -e 1 || skip_test_ 'skipping part of this test; you lack perl'
+
+$PERL -e 'BEGIN { $n = 16 * 1024; *F = *STDOUT }' \
+ -e 'for (1..100) { sysseek (*F, $n, 1)' \
+ -e '&& syswrite (*F, "."x$n) or die "$!"}' > j1 || fail=1
+
+cp --sparse=always j1 j2 || fail=1
+cmp j1 j2 || fail=1
+
+filefrag j1 | grep extent \
+ || skip_test_ 'skipping part of this test; you lack filefrag'
+
+# Here is sample filefrag output:
+# $ perl -e 'BEGIN{$n=16*1024; *F=*STDOUT}' \
+# -e 'for (1..5) { sysseek(*F,$n,1)' \
+# -e '&& syswrite *F,"."x$n or die "$!"}' > j
+# $ filefrag -v j
+# Filesystem type is: ef53
+# File size of j is 163840 (40 blocks, blocksize 4096)
+# ext logical physical expected length flags
+# 0 4 6258884 4
+# 1 12 6258892 6258887 4
+# 2 20 6258900 6258895 4
+# 3 28 6258908 6258903 4
+# 4 36 6258916 6258911 4 eof
+# j: 6 extents found
+
+# exclude the physical block numbers; they always differ
+filefrag -v j1 | awk '/^ / {print $1,$2,$NF}' > ff1 || fail=1
+filefrag -v j2 | awk '/^ / {print $1,$2,$NF}' > ff2 || fail=1
+compare ff1 ff2 || fail=1
+
Exit $fail
--
1.7.1.348.gb26ba
>From e84f881cb5c2eb92f3b6d5bddaef50c3e811bc30 Mon Sep 17 00:00:00 2001
From: Jim Meyering <address@hidden>
Date: Sat, 22 May 2010 10:22:58 +0200
Subject: [PATCH 4/5] tests: require root access only if current partition is
not ext4
* tests/cp/sparse-fiemap: Don't require root access if current
partition is ext4.
---
tests/cp/sparse-fiemap | 44 +++++++++++++++++++++++++-------------------
1 files changed, 25 insertions(+), 19 deletions(-)
diff --git a/tests/cp/sparse-fiemap b/tests/cp/sparse-fiemap
index b1643be..371bced 100755
--- a/tests/cp/sparse-fiemap
+++ b/tests/cp/sparse-fiemap
@@ -22,28 +22,34 @@ if test "$VERBOSE" = yes; then
fi
. $srcdir/test-lib.sh
-require_root_
-cwd=`pwd`
-cleanup_() { cd /; umount "$cwd/mnt"; }
-
-skip=0
-# Create an ext4 loopback file system
-dd if=/dev/zero of=blob bs=8192 count=1000 || skip=1
-mkdir mnt
-mkfs -t ext4 -F blob ||
- skip_test_ "failed to create ext4 file system"
-mount -oloop blob mnt || skip=1
-echo test > mnt/f || skip=1
-test -s mnt/f || skip=1
-
-test $skip = 1 &&
- skip_test_ "insufficient mount/ext4 support"
+if df -T -t ext4 . ; then
+ : # Current dir is on an ext4 partition. Good!
+else
+ # It's not; we need to create one, hence we need root access.
+ require_root_
+
+ cwd=$PWD
+ cleanup_() { cd /; umount "$cwd/mnt"; }
+
+ skip=0
+ # Create an ext4 loopback file system
+ dd if=/dev/zero of=blob bs=8192 count=1000 || skip=1
+ mkdir mnt
+ mkfs -t ext4 -F blob ||
+ skip_test_ "failed to create ext4 file system"
+ mount -oloop blob mnt || skip=1
+ echo test > mnt/f || skip=1
+ test -s mnt/f || skip=1
+
+ test $skip = 1 &&
+ skip_test_ "insufficient mount/ext4 support"
+
+ cd mnt || fail=1
+fi
# Create a 1TiB sparse file
-dd if=/dev/zero of=mnt/sparse bs=1k count=1 seek=1G || framework_failure
-
-cd mnt || fail=1
+dd if=/dev/zero of=sparse bs=1k count=1 seek=1G || framework_failure
# It takes many minutes to copy this sparse file using the old method.
# By contrast, it takes far less than 1 second using FIEMAP-copy.
--
1.7.1.348.gb26ba
>From 213c9247a406b267bc5819ccbe3b729e9557c675 Mon Sep 17 00:00:00 2001
From: Jim Meyering <address@hidden>
Date: Sat, 22 May 2010 10:21:46 +0200
Subject: [PATCH 5/5] tests: fiemap test improvement
* tests/cp/sparse-fiemap: More tests.
---
tests/cp/sparse-fiemap | 69 +++++++++++++++++++++++++-----------------------
1 files changed, 36 insertions(+), 33 deletions(-)
diff --git a/tests/cp/sparse-fiemap b/tests/cp/sparse-fiemap
index 371bced..ef3742e 100755
--- a/tests/cp/sparse-fiemap
+++ b/tests/cp/sparse-fiemap
@@ -38,14 +38,14 @@ else
mkdir mnt
mkfs -t ext4 -F blob ||
skip_test_ "failed to create ext4 file system"
- mount -oloop blob mnt || skip=1
- echo test > mnt/f || skip=1
- test -s mnt/f || skip=1
+ mount -oloop blob mnt || skip=1
+ cd mnt || skip=1
+ echo test > f || skip=1
+ test -s f || skip=1
test $skip = 1 &&
skip_test_ "insufficient mount/ext4 support"
- cd mnt || fail=1
fi
# Create a 1TiB sparse file
@@ -67,34 +67,37 @@ test $(stat --printf %s sparse) = $(stat --printf %s
fiemap) || fail=1
$PERL -e 1 || skip_test_ 'skipping part of this test; you lack perl'
-$PERL -e 'BEGIN { $n = 16 * 1024; *F = *STDOUT }' \
- -e 'for (1..100) { sysseek (*F, $n, 1)' \
- -e '&& syswrite (*F, "."x$n) or die "$!"}' > j1 || fail=1
-
-cp --sparse=always j1 j2 || fail=1
-cmp j1 j2 || fail=1
-
-filefrag j1 | grep extent \
- || skip_test_ 'skipping part of this test; you lack filefrag'
-
-# Here is sample filefrag output:
-# $ perl -e 'BEGIN{$n=16*1024; *F=*STDOUT}' \
-# -e 'for (1..5) { sysseek(*F,$n,1)' \
-# -e '&& syswrite *F,"."x$n or die "$!"}' > j
-# $ filefrag -v j
-# Filesystem type is: ef53
-# File size of j is 163840 (40 blocks, blocksize 4096)
-# ext logical physical expected length flags
-# 0 4 6258884 4
-# 1 12 6258892 6258887 4
-# 2 20 6258900 6258895 4
-# 3 28 6258908 6258903 4
-# 4 36 6258916 6258911 4 eof
-# j: 6 extents found
-
-# exclude the physical block numbers; they always differ
-filefrag -v j1 | awk '/^ / {print $1,$2,$NF}' > ff1 || fail=1
-filefrag -v j2 | awk '/^ / {print $1,$2,$NF}' > ff2 || fail=1
-compare ff1 ff2 || fail=1
+for i in $(seq 20); do
+ for j in 1 2 31 100; do
+ $PERL -e 'BEGIN { $n = '$i' * 1024; *F = *STDOUT }' \
+ -e 'for (1..'$j') { sysseek (*F, $n, 1)' \
+ -e '&& syswrite (*F, "."x$n) or die "$!"}' > j1 || fail=1
+
+ cp --sparse=always j1 j2 || fail=1
+ cmp j1 j2 || fail=1
+ filefrag -v j1 | grep extent \
+ || skip_test_ 'skipping part of this test; you lack filefrag'
+
+ # Here is sample filefrag output:
+ # $ perl -e 'BEGIN{$n=16*1024; *F=*STDOUT}' \
+ # -e 'for (1..5) { sysseek(*F,$n,1)' \
+ # -e '&& syswrite *F,"."x$n or die "$!"}' > j
+ # $ filefrag -v j
+ # Filesystem type is: ef53
+ # File size of j is 163840 (40 blocks, blocksize 4096)
+ # ext logical physical expected length flags
+ # 0 4 6258884 4
+ # 1 12 6258892 6258887 4
+ # 2 20 6258900 6258895 4
+ # 3 28 6258908 6258903 4
+ # 4 36 6258916 6258911 4 eof
+ # j: 6 extents found
+
+ # exclude the physical block numbers; they always differ
+ filefrag -v j1 | awk '/^ / {print $1,$2}' > ff1 || fail=1
+ filefrag -v j2 | awk '/^ / {print $1,$2}' > ff2 || fail=1
+ compare ff1 ff2 || fail=1
+ done
+done
Exit $fail
--
1.7.1.348.gb26ba
- bug#6131: [PATCH]: fiemap support for efficient sparse file copy, (continued)
- bug#6131: [PATCH]: fiemap support for efficient sparse file copy, Jim Meyering, 2010/05/21
- bug#6131: [PATCH]: fiemap support for efficient sparse file copy, jeff.liu, 2010/05/21
- bug#6131: [PATCH]: fiemap support for efficient sparse file copy, Jim Meyering, 2010/05/24
- bug#6131: [PATCH]: fiemap support for efficient sparse file copy, jeff.liu, 2010/05/24
- bug#6131: [PATCH]: fiemap support for efficient sparse file copy, jeff.liu, 2010/05/24
- bug#6131: [PATCH]: fiemap support for efficient sparse file copy, Jim Meyering, 2010/05/25
- bug#6131: [PATCH]: fiemap support for efficient sparse file copy, jeff.liu, 2010/05/25
- bug#6131: [PATCH]: fiemap support for efficient sparse file copy, jeff.liu, 2010/05/21
- bug#6131: [PATCH]: fiemap support for efficient sparse file copy,
Jim Meyering <=
- bug#6131: [PATCH]: fiemap support for efficient sparse file copy, jeff.liu, 2010/05/27
- bug#6131: [PATCH]: fiemap support for efficient sparse file copy, Sunil Mushran, 2010/05/27
- bug#6131: [PATCH]: fiemap support for efficient sparse file copy, Jim Meyering, 2010/05/27
- bug#6131: [PATCH]: fiemap support for efficient sparse file copy, Sunil Mushran, 2010/05/27
- bug#6131: [PATCH]: fiemap support for efficient sparse file copy, Jim Meyering, 2010/05/27
- bug#6131: [PATCH]: fiemap support for efficient sparse file copy, Jim Meyering, 2010/05/27
- bug#6131: [PATCH]: fiemap support for efficient sparse file copy, Tao Ma, 2010/05/28
- bug#6131: [PATCH]: fiemap support for efficient sparse file copy, Jim Meyering, 2010/05/28
- bug#6131: [PATCH]: fiemap support for efficient sparse file copy, Tao Ma, 2010/05/30
- bug#6131: [PATCH]: fiemap support for efficient sparse file copy, Jim Meyering, 2010/05/30