selftests/bpf: Copy file using read/write in local storage test

Splice (copy_file_range) doesn't work on all filesystems. I'm running
test kernels on top of my read-only disk image and it uses plan9 under the
hood. This prevents test_local_storage from successfully passing.

There is really no technical reason to use splice, so lets do
old-school read/write to copy file; this should work in all
environments.

Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20201202174947.3621989-1-sdf@google.com
This commit is contained in:
Stanislav Fomichev 2020-12-02 09:49:47 -08:00 committed by Alexei Starovoitov
parent 0d1e026959
commit a874c8c389

View File

@ -21,14 +21,6 @@ static inline int sys_pidfd_open(pid_t pid, unsigned int flags)
return syscall(__NR_pidfd_open, pid, flags);
}
static inline ssize_t copy_file_range(int fd_in, loff_t *off_in, int fd_out,
loff_t *off_out, size_t len,
unsigned int flags)
{
return syscall(__NR_copy_file_range, fd_in, off_in, fd_out, off_out,
len, flags);
}
static unsigned int duration;
#define TEST_STORAGE_VALUE 0xbeefdead
@ -47,6 +39,7 @@ static int copy_rm(char *dest)
{
int fd_in, fd_out = -1, ret = 0;
struct stat stat;
char *buf = NULL;
fd_in = open("/bin/rm", O_RDONLY);
if (fd_in < 0)
@ -64,18 +57,33 @@ static int copy_rm(char *dest)
goto out;
}
ret = copy_file_range(fd_in, NULL, fd_out, NULL, stat.st_size, 0);
if (ret == -1) {
buf = malloc(stat.st_blksize);
if (!buf) {
ret = -errno;
goto out;
}
while (ret = read(fd_in, buf, stat.st_blksize), ret > 0) {
ret = write(fd_out, buf, ret);
if (ret < 0) {
ret = -errno;
goto out;
}
}
if (ret < 0) {
ret = -errno;
goto out;
}
/* Set executable permission on the copied file */
ret = chmod(dest, 0100);
if (ret == -1)
ret = -errno;
out:
free(buf);
close(fd_in);
close(fd_out);
return ret;