We want a shared way to use mmap in a way that we can test for the SIGBUS, provide a shared routine which other tests can leverage. Suggested-by: "Darrick J. Wong" <djwong@xxxxxxxxxx> Signed-off-by: Luis Chamberlain <mcgrof@xxxxxxxxxx> --- common/rc | 28 ++++++++++++++++++++++++++++ tests/generic/574 | 36 ++++-------------------------------- 2 files changed, 32 insertions(+), 32 deletions(-) diff --git a/common/rc b/common/rc index 163041fea5b9..fa7942809d6c 100644 --- a/common/rc +++ b/common/rc @@ -52,6 +52,34 @@ _pwrite_byte() { $XFS_IO_PROG $xfs_io_args -f -c "pwrite -S $pattern $offset $len" "$file" } +_round_up_to_page_boundary() +{ + local n=$1 + local page_size=$(_get_page_size) + + echo $(( (n + page_size - 1) & ~(page_size - 1) )) +} + +_mread() +{ + local file=$1 + local offset=$2 + local length=$3 + local map_len=$(_round_up_to_page_boundary $(_get_filesize $file)) + + # Some callers expect xfs_io to crash with SIGBUS due to the mread, + # causing the shell to print "Bus error" to stderr. To allow this + # message to be redirected, execute xfs_io in a new shell instance. + # However, for this to work reliably, we also need to prevent the new + # shell instance from optimizing out the fork and directly exec'ing + # xfs_io. The easiest way to do that is to append 'true' to the + # commands, so that xfs_io is no longer the last command the shell sees. + # Don't let it write core files to the filesystem. + bash -c "trap '' SIGBUS; ulimit -c 0; $XFS_IO_PROG -r $file \ + -c 'mmap -r 0 $map_len' \ + -c 'mread -v $offset $length'; true" +} + # mmap-write a byte into a range of a file _mwrite_byte() { local pattern="$1" diff --git a/tests/generic/574 b/tests/generic/574 index cb42baaa67aa..d44c23e5abc2 100755 --- a/tests/generic/574 +++ b/tests/generic/574 @@ -52,34 +52,6 @@ setup_zeroed_file() cmp $fsv_orig_file $fsv_file } -round_up_to_page_boundary() -{ - local n=$1 - local page_size=$(_get_page_size) - - echo $(( (n + page_size - 1) & ~(page_size - 1) )) -} - -mread() -{ - local file=$1 - local offset=$2 - local length=$3 - local map_len=$(round_up_to_page_boundary $(_get_filesize $file)) - - # Some callers expect xfs_io to crash with SIGBUS due to the mread, - # causing the shell to print "Bus error" to stderr. To allow this - # message to be redirected, execute xfs_io in a new shell instance. - # However, for this to work reliably, we also need to prevent the new - # shell instance from optimizing out the fork and directly exec'ing - # xfs_io. The easiest way to do that is to append 'true' to the - # commands, so that xfs_io is no longer the last command the shell sees. - # Don't let it write core files to the filesystem. - bash -c "trap '' SIGBUS; ulimit -c 0; $XFS_IO_PROG -r $file \ - -c 'mmap -r 0 $map_len' \ - -c 'mread -v $offset $length'; true" -} - corruption_test() { local block_size=$1 @@ -142,7 +114,7 @@ corruption_test() fi # Reading the full file via mmap should fail. - mread $fsv_file 0 $file_len >/dev/null 2>$tmp.err + _mread $fsv_file 0 $file_len >/dev/null 2>$tmp.err if ! grep -q 'Bus error' $tmp.err; then echo "Didn't see SIGBUS when reading file via mmap" cat $tmp.err @@ -150,7 +122,7 @@ corruption_test() # Reading just the corrupted part via mmap should fail. if ! $is_merkle_tree; then - mread $fsv_file $zap_offset $zap_len >/dev/null 2>$tmp.err + _mread $fsv_file $zap_offset $zap_len >/dev/null 2>$tmp.err if ! grep -q 'Bus error' $tmp.err; then echo "Didn't see SIGBUS when reading corrupted part via mmap" cat $tmp.err @@ -174,10 +146,10 @@ corrupt_eof_block_test() head -c $zap_len /dev/zero | tr '\0' X \ | _fsv_scratch_corrupt_bytes $fsv_file $file_len - mread $fsv_file $file_len $zap_len >$tmp.out 2>$tmp.err + _mread $fsv_file $file_len $zap_len >$tmp.out 2>$tmp.err head -c $file_len /dev/zero >$tmp.zeroes - mread $tmp.zeroes $file_len $zap_len >$tmp.zeroes_out + _mread $tmp.zeroes $file_len $zap_len >$tmp.zeroes_out grep -q 'Bus error' $tmp.err || diff $tmp.out $tmp.zeroes_out } -- 2.43.0