From: Omar Sandoval <osandov@xxxxxx> generic/427 fails on Btrfs with a cryptic "pread: Success" message. This is because an aio pwrite fails with ENOSPC, so the file isn't as long as we expect it to be. Make sure we check the result of the aio writes and also print a more explicit message for short reads (which are technically valid but in practice shouldn't happen for this test case). Now the test fails with a much more informative "pwrite: No space left on device". Signed-off-by: Omar Sandoval <osandov@xxxxxx> --- src/aio-dio-regress/aio-dio-eof-race.c | 22 +++++++++++++++++++++- 1 file changed, 21 insertions(+), 1 deletion(-) diff --git a/src/aio-dio-regress/aio-dio-eof-race.c b/src/aio-dio-regress/aio-dio-eof-race.c index bb1890b5..04479035 100644 --- a/src/aio-dio-regress/aio-dio-eof-race.c +++ b/src/aio-dio-regress/aio-dio-eof-race.c @@ -154,6 +154,9 @@ int main(int argc, char *argv[]) /* Keep extending until size_MB */ while (eof < size_MB * 1024 * 1024) { + ssize_t sret; + int i; + memset(buf, IO_PATTERN, buf_size); fstat(fd, &statbuf); eof = statbuf.st_size; @@ -186,15 +189,32 @@ int main(int argc, char *argv[]) return 1; } + for (i = 0; i < err; i++) { + /* + * res is unsigned for some reason, so this is the best + * way to detect that it contains a negative errno. + */ + if (evs[i].res > buf_size / 4) { + fprintf(stderr, "pwrite: %s\n", + strerror(-evs[i].res)); + return 1; + } + } + /* * And then read it back. * * Using pread to keep it simple, but AIO has the same effect. * eof is the prior eof; we just wrote buf_size more. */ - if (pread(fd, buf, buf_size, eof) != buf_size) { + sret = pread(fd, buf, buf_size, eof); + if (sret == -1) { perror("pread"); return 1; + } else if (sret != buf_size) { + fprintf(stderr, "short read %zd was less than %zu\n", + sret, buf_size); + return 1; } /* -- 2.17.0 -- To unsubscribe from this list: send the line "unsubscribe fstests" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html