In my patch series to replace fs/fat with "ff.c", I enhanced ff.c to optimize file reading, so that reads of contiguous clusters are submitted to the IO device as a single read. This test attempts to torture-test edge-cases of that enhancement.

BTW, the only way I found to validate that this script actually does create non-contiguous files was to manually inspect the FAT bitmap in a hex dump of the FAT image. hdparm --fibmap doesn't work on loop-mounted filesystems. filefrag -v -e seems to lie about files being contiguous when they aren't.

Signed-off-by: Stephen Warren swarren@wwwdotorg.org --- v2: * Check for missing pre-requisite binaries, and print an explicit error message if any are missing. * Create mount-point rather than assuming it exists. * Add a comment describing the script's operation. --- test/fs/fat-noncontig-test.sh | 113 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 113 insertions(+) create mode 100755 test/fs/fat-noncontig-test.sh

diff --git a/test/fs/fat-noncontig-test.sh b/test/fs/fat-noncontig-test.sh new file mode 100755 index 000000000000..f153c97bbf05 --- /dev/null +++ b/test/fs/fat-noncontig-test.sh @@ -0,0 +1,113 @@ +#!/bin/bash + +# (C) Copyright 2015 Stephen Warren +# +# SPDX-License-Identifier: GPL-2.0+ + +# This script tests U-Boot's FAT filesystem code's ability to read non- +# contiguous files. + +# When porting the ff.c FAT parsing code into U-Boot, it was found that ff.c +# always reads files cluster-by-cluster, which results in poor performance. +# This was solved by adding a patch to ff.c to coalesce reads of adjacent +# clusters. Since this patch needed to correctly handle non-contiguous files, +# this test was written to validate that. +# +# To execute the test, simply run it from the U-Boot source root directory: +# +# cd u-boot +# ./test/fs/fat-noncontig-test.sh +# +# The test will create a FAT filesystem image, record the CRC of a randomly +# generated file in the image, build U-Boot sandbox, invoke U-Boot sandbox to +# read the file and validate that the CRCs match. Expected output is shown +# below. The important part of the log is the penultimate line that contains +# either "PASS" or "FAILURE". +# +# mkfs.fat 3.0.26 (2014-03-07) +# +# +# U-Boot 2015.10-rc4-00018-g4b22a3e5513f (Oct 03 2015 - 13:49:23 -0600) +# +# DRAM: 128 MiB +# Using default environment +# +# In: serial +# Out: lcd +# Err: lcd +# Net: No ethernet found. +# => host bind 0 sandbox/fat-noncontig.img +# => load host 0:0 1000 noncontig.img +# 33584964 bytes read in 18 ms (1.7 GiB/s) +# => crc32 1000 $filesize 0 +# crc32 for 00001000 ... 02008743 ==> 6a080523 +# => if itest.l *0 != 2305086a; then echo FAILURE; else echo PASS; fi +# PASS +# => reset +# +# All temporary files used by this script are created in ./sandbox to avoid +# polluting the source tree. test/fs/fs-test.sh also uses this directory for +# the same purpose. +# +# TODO: Integrate this (and many other corner-cases e.g. different types of +# FAT) with fs-test.sh so that a single script tests everything filesystem- +# related. + +odir=sandbox +img=${odir}/fat-noncontig.img +mnt=${odir}/mnt +fill=/dev/urandom +testfn=noncontig.img +mnttestfn=${mnt}/${testfn} +crcaddr=0 +loadaddr=1000 + +for prereq in fallocate mkfs.fat dd crc32; do + if [ ! -x "`which $prereq`" ]; then + echo "Missing $prereq binary. Exiting!" + exit 1 + fi +done + +make O=${odir} -s sandbox_defconfig && make O=${odir} -s -j8 + +mkdir -p ${mnt} +if [ ! -f ${img} ]; then + fallocate -l 40M ${img} + mkfs.fat ${img} + + sudo mount -o loop,uid=$(id -u) ${img} ${mnt} + + for ((sects=8; sects < 512; sects += 8)); do + fn=${mnt}/keep-${sects}.img + dd if=${fill} of=${fn} bs=512 count=${sects} >/dev/null 2>&1 + fn=${mnt}/remove-${sects}.img + dd if=${fill} of=${fn} bs=512 count=${sects} >/dev/null 2>&1 + done + + rm -f ${mnt}/remove-*.img + + # 511 deliberately to trigger a file size that's not a multiple of the + # sector size (ignoring sizes that are multiples of both). + dd if=${fill} of=${mnttestfn} bs=511 >/dev/null 2>&1 + + sudo umount ${mnt} +fi + +sudo mount -o ro,loop,uid=$(id -u) ${img} ${mnt} +crc=0x`crc32 ${mnttestfn}` +sudo umount ${mnt} + +crc=`printf %02x%02x%02x%02x \ + $((${crc} & 0xff)) \ + $(((${crc} >> 8) & 0xff)) \ + $(((${crc} >> 16) & 0xff)) \ + $((${crc} >> 24))` + +./sandbox/u-boot << EOF +host bind 0 ${img} +load host 0:0 ${loadaddr} ${testfn} +crc32 ${loadaddr} $filesize ${crcaddr} +if itest.l *${crcaddr} != ${crc}; then echo FAILURE; else echo PASS; fi +reset +EOF