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 --- test/fs/fat-noncontig-test.sh | 52 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 52 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..8153708bbf78 --- /dev/null +++ b/test/fs/fat-noncontig-test.sh @@ -0,0 +1,52 @@ +#!/bin/bash + +odir=sandbox +img=${odir}/fat.img +mnt=/mnt/tmp +fill=/dev/urandom +testfn=noncontig.img +mnttestfn=${mnt}/${testfn} +crcaddr=0 +loadaddr=1000 + +make O=${odir} -s sandbox_defconfig && make O=${odir} -s -j8 + +if [ ! -f ${img} ]; then + fallocate -l 40M ${img} + mkfs -t 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