All of lore.kernel.org
 help / color / mirror / Atom feed
From: Christoph Hellwig <hch@lst.de>
To: fstests@vger.kernel.org
Cc: linux-btrfs@vger.kernel.org
Subject: [PATCH 1/9] btrfs: add a helpers for read repair testing
Date: Tue, 24 May 2022 09:18:30 +0200	[thread overview]
Message-ID: <20220524071838.715013-2-hch@lst.de> (raw)
In-Reply-To: <20220524071838.715013-1-hch@lst.de>

Add a few helpers to consolidate code for btrfs read repair testing:

 - _btrfs_get_first_logical() gets the btrfs logical address for the
   first extent in a file
 - _btrfs_get_device_path and _btrfs_get_physical use the
   btrfs-map-logical tool to find the device path and physical address
   for btrfs logical address for a specific mirror
 - _btrfs_direct_read_on_mirror and _btrfs_buffered_read_on_mirror
   read the data from a specific mirror

These will be used to consolidate the read repair tests and avoid
duplication for new tests.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 common/btrfs  | 75 +++++++++++++++++++++++++++++++++++++++++++++++++++
 common/config |  1 +
 2 files changed, 76 insertions(+)

diff --git a/common/btrfs b/common/btrfs
index ac597ca4..129a83f7 100644
--- a/common/btrfs
+++ b/common/btrfs
@@ -505,3 +505,78 @@ _btrfs_metadump()
 	$BTRFS_IMAGE_PROG "$device" "$dumpfile"
 	[ -n "$DUMP_COMPRESSOR" ] && $DUMP_COMPRESSOR -f "$dumpfile" &> /dev/null
 }
+
+# Return the btrfs logical address for the first block in a file
+_btrfs_get_first_logical()
+{
+	local file=$1
+	_require_command "$FILEFRAG_PROG" filefrag
+
+	${FILEFRAG_PROG} -v $SCRATCH_MNT/foobar >> $seqres.full
+	${FILEFRAG_PROG} -v $file | _filter_filefrag | cut -d '#' -f 1
+}
+
+# Find the device path for a btrfs logical offset
+_btrfs_get_device_path()
+{
+	local logical=$1
+	local stripe=$2
+
+	_require_command "$BTRFS_MAP_LOGICAL_PROG" btrfs-map-logical
+
+	$BTRFS_MAP_LOGICAL_PROG -l $logical $SCRATCH_DEV | \
+		$AWK_PROG "(\$1 ~ /mirror/ && \$2 ~ /$stripe/) { print \$8 }"
+}
+
+
+# Find the device physical sector for a btrfs logical offset
+_btrfs_get_physical()
+{
+	local logical=$1
+	local stripe=$2
+
+	_require_command "$BTRFS_MAP_LOGICAL_PROG" btrfs-map-logical
+
+	$BTRFS_MAP_LOGICAL_PROG -l $logical $SCRATCH_DEV >> $seqres.full 2>&1
+	$BTRFS_MAP_LOGICAL_PROG -l $logical $SCRATCH_DEV | \
+		$AWK_PROG "(\$1 ~ /mirror/ && \$2 ~ /$stripe/) { print \$6 }"
+}
+
+# Read from a specific stripe to test read recovery that corrupted a specific
+# stripe.  Btrfs uses the PID to select the mirror, so keep reading until the
+# xfs_io process that performed the read was executed with a PID that ends up
+# on the intended mirror.
+_btrfs_direct_read_on_mirror()
+{
+	local mirror=$1
+	local nr_mirrors=$2
+	local file=$3
+	local offset=$4
+	local size=$5
+
+	while [[ -z $( (( BASHPID % nr_mirrors == mirror )) &&
+		exec $XFS_IO_PROG -d \
+			-c "pread -b $size $offset $size" $file) ]]; do
+		:
+	done
+}
+
+# Read from a specific stripe to test read recovery that corrupted a specific
+# stripe.  Btrfs uses the PID to select the mirror, so keep reading until the
+# xfs_io process that performed the read was executed with a PID that ends up
+# on the intended mirror.
+_btrfs_buffered_read_on_mirror()
+{
+	local mirror=$1
+	local nr_mirrors=$2
+	local file=$3
+	local offset=$4
+	local size=$5
+
+	echo 3 > /proc/sys/vm/drop_caches
+	while [[ -z $( (( BASHPID % nr_mirrors == mirror )) &&
+		exec $XFS_IO_PROG \
+			-c "pread -b $size $offset $size" $file) ]]; do
+		:
+	done
+}
diff --git a/common/config b/common/config
index c6428f90..df20afc1 100644
--- a/common/config
+++ b/common/config
@@ -228,6 +228,7 @@ export E2IMAGE_PROG="$(type -P e2image)"
 export BLKZONE_PROG="$(type -P blkzone)"
 export GZIP_PROG="$(type -P gzip)"
 export BTRFS_IMAGE_PROG="$(type -P btrfs-image)"
+export BTRFS_MAP_LOGICAL_PROG=$(type -P btrfs-map-logical)
 
 # use 'udevadm settle' or 'udevsettle' to wait for lv to be settled.
 # newer systems have udevadm command but older systems like RHEL5 don't.
-- 
2.30.2


  reply	other threads:[~2022-05-24  7:18 UTC|newest]

Thread overview: 23+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-05-24  7:18 two more btrfs read repair tests v2 Christoph Hellwig
2022-05-24  7:18 ` Christoph Hellwig [this message]
2022-05-24 13:18   ` [PATCH 1/9] btrfs: add a helpers for read repair testing Qu Wenruo
2022-05-27 11:22   ` Nikolay Borisov
2022-05-27 13:33     ` Christoph Hellwig
2022-05-24  7:18 ` [PATCH 2/9] btrfs/140: use common read repair helpers Christoph Hellwig
2022-05-24 13:21   ` Qu Wenruo
2022-05-24  7:18 ` [PATCH 3/9] btrfs/141: " Christoph Hellwig
2022-05-24 13:21   ` Qu Wenruo
2022-05-24  7:18 ` [PATCH 4/9] btrfs/142: " Christoph Hellwig
2022-05-24 13:21   ` Qu Wenruo
2022-05-24  7:18 ` [PATCH 5/9] btrfs/143: " Christoph Hellwig
2022-05-24 13:21   ` Qu Wenruo
2022-05-24  7:18 ` [PATCH 6/9] btrfs/157: use _btrfs_get_first_logical Christoph Hellwig
2022-05-24 13:21   ` Qu Wenruo
2022-05-24  7:18 ` [PATCH 7/9] btrfs/215: " Christoph Hellwig
2022-05-24 13:21   ` Qu Wenruo
2022-05-24  7:18 ` [PATCH 8/9] btrfs: test repair with sectors corrupted in multiple mirrors Christoph Hellwig
2022-05-24 13:28   ` Qu Wenruo
2022-06-02 11:30   ` Filipe Manana
2022-06-02 12:07     ` Christoph Hellwig
2022-05-24  7:18 ` [PATCH 9/9] btrfs: test repair with corrupted sectors interleaved over " Christoph Hellwig
2022-05-24 13:30   ` Qu Wenruo

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20220524071838.715013-2-hch@lst.de \
    --to=hch@lst.de \
    --cc=fstests@vger.kernel.org \
    --cc=linux-btrfs@vger.kernel.org \
    --subject='Re: [PATCH 1/9] btrfs: add a helpers for read repair testing' \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.