On Wed, Aug 28, 2024 at 12:37 PM Aleksa Sarai <cyphar@xxxxxxxxxx> wrote: > > Now that open_by_handle_at(2) can return u64 mount IDs, do some tests to > make sure they match properly as part of the regular open_by_handle > tests. > > Link: https://lore.kernel.org/all/20240801-exportfs-u64-mount-id-v3-0-be5d6283144a@xxxxxxxxxx/ > Signed-off-by: Aleksa Sarai <cyphar@xxxxxxxxxx> > --- > src/open_by_handle.c | 123 ++++++++++++++++++++++++++++++++----------- > tests/generic/426 | 1 + > 2 files changed, 93 insertions(+), 31 deletions(-) > > diff --git a/src/open_by_handle.c b/src/open_by_handle.c > index d9c802ca9bd1..cbd68aeadac1 100644 > --- a/src/open_by_handle.c > +++ b/src/open_by_handle.c > @@ -86,10 +86,15 @@ Examples: > #include <errno.h> > #include <linux/limits.h> > #include <libgen.h> > +#include <stdint.h> > > #include <sys/stat.h> > #include "statx.h" > > +#ifndef AT_HANDLE_MNT_ID_UNIQUE > +# define AT_HANDLE_MNT_ID_UNIQUE 0x001 > +#endif > + > #define MAXFILES 1024 > > struct handle { > @@ -99,7 +104,7 @@ struct handle { > > void usage(void) > { > - fprintf(stderr, "usage: open_by_handle [-cludmrwapknhs] [<-i|-o> <handles_file>] <test_dir> [num_files]\n"); > + fprintf(stderr, "usage: open_by_handle [-cludMmrwapknhs] [<-i|-o> <handles_file>] <test_dir> [num_files]\n"); > fprintf(stderr, "\n"); > fprintf(stderr, "open_by_handle -c <test_dir> [N] - create N test files under test_dir, try to get file handles and exit\n"); > fprintf(stderr, "open_by_handle <test_dir> [N] - get file handles of test files, drop caches and try to open by handle\n"); > @@ -111,6 +116,7 @@ void usage(void) > fprintf(stderr, "open_by_handle -l <test_dir> [N] - create hardlinks to test files, drop caches and try to open by handle\n"); > fprintf(stderr, "open_by_handle -u <test_dir> [N] - unlink (hardlinked) test files, drop caches and try to open by handle\n"); > fprintf(stderr, "open_by_handle -d <test_dir> [N] - unlink test files and hardlinks, drop caches and try to open by handle\n"); > + fprintf(stderr, "open_by_handle -M <test_dir> [N] - confirm that the mount id returned by name_to_handle_at matches the mount id in statx\n"); > fprintf(stderr, "open_by_handle -m <test_dir> [N] - rename test files, drop caches and try to open by handle\n"); > fprintf(stderr, "open_by_handle -p <test_dir> - create/delete and try to open by handle also test_dir itself\n"); > fprintf(stderr, "open_by_handle -i <handles_file> <test_dir> [N] - read test files handles from file and try to open by handle\n"); > @@ -120,6 +126,81 @@ void usage(void) > exit(EXIT_FAILURE); > } > > +int do_name_to_handle_at(const char *fname, struct file_handle *fh, int bufsz, > + int checkmountid) > +{ > + int ret; > + int mntid_short; > + > + uint64_t mntid_unique; > + uint64_t statx_mntid_short = 0, statx_mntid_unique = 0; > + struct handle dummy_fh; > + > + if (checkmountid) { > + struct statx statxbuf; > + > + /* Get both the short and unique mount id. */ > + if (statx(AT_FDCWD, fname, 0, STATX_MNT_ID, &statxbuf) < 0) { > + fprintf(stderr, "%s: statx(STATX_MNT_ID): %m\n", fname); > + return EXIT_FAILURE; > + } > + if (!(statxbuf.stx_mask & STATX_MNT_ID)) { > + fprintf(stderr, "%s: no STATX_MNT_ID in stx_mask\n", fname); > + return EXIT_FAILURE; > + } > + statx_mntid_short = statxbuf.stx_mnt_id; > + > + if (statx(AT_FDCWD, fname, 0, STATX_MNT_ID_UNIQUE, &statxbuf) < 0) { > + fprintf(stderr, "%s: statx(STATX_MNT_ID_UNIQUE): %m\n", fname); > + return EXIT_FAILURE; This failure will break the test on LTS kernels - we don't want that. Instead I think you should: - drop the -M option - get statx_mntid_unique here IF kernel supports STATX_MNT_ID_UNIQUE and then... > + } > + if (!(statxbuf.stx_mask & STATX_MNT_ID_UNIQUE)) { > + fprintf(stderr, "%s: no STATX_MNT_ID_UNIQUE in stx_mask\n", fname); > + return EXIT_FAILURE; > + } > + statx_mntid_unique = statxbuf.stx_mnt_id; > + } > + > + fh->handle_bytes = bufsz; > + ret = name_to_handle_at(AT_FDCWD, fname, fh, &mntid_short, 0); > + if (bufsz < fh->handle_bytes) { > + /* Query the filesystem required bufsz and the file handle */ > + if (ret != -1 || errno != EOVERFLOW) { > + fprintf(stderr, "%s: unexpected result from name_to_handle_at: %d (%m)\n", fname, ret); > + return EXIT_FAILURE; > + } > + ret = name_to_handle_at(AT_FDCWD, fname, fh, &mntid_short, 0); > + } > + if (ret < 0) { > + fprintf(stderr, "%s: name_to_handle: %m\n", fname); > + return EXIT_FAILURE; > + } > + > + if (checkmountid) { > + if (mntid_short != (int) statx_mntid_short) { > + fprintf(stderr, "%s: name_to_handle_at returned a different mount ID to STATX_MNT_ID: %u != %lu\n", fname, mntid_short, statx_mntid_short); > + return EXIT_FAILURE; > + } > + > + /* > + * Get the unique mount ID. We don't need to get another copy of the > + * handle so store it in a dummy struct. > + */ > + dummy_fh.fh.handle_bytes = fh->handle_bytes; > + if (name_to_handle_at(AT_FDCWD, fname, &dummy_fh.fh, (int *) &mntid_unique, AT_HANDLE_MNT_ID_UNIQUE) < 0) { > + fprintf(stderr, "%s: name_to_handle_at(AT_HANDLE_MNT_ID_UNIQUE): %m\n", fname); > + return EXIT_FAILURE; > + } > + > + if (mntid_unique != statx_mntid_unique) { > + fprintf(stderr, "%s: name_to_handle_at(AT_HANDLE_MNT_ID_UNIQUE) returned a different mount ID to STATX_MNT_ID_UNIQUE: %lu != %lu\n", fname, mntid_unique, statx_mntid_unique); > + return EXIT_FAILURE; > + } - check statx_mntid_unique here IFF statx_mntid_unique is set - always check statx_mntid_short (what could be a reason to not check it?) > + } > + > + return 0; > +} > + > int main(int argc, char **argv) > { > int i, c; > @@ -132,19 +213,20 @@ int main(int argc, char **argv) > char fname2[PATH_MAX]; > char *test_dir; > char *mount_dir; > - int mount_fd, mount_id; > + int mount_fd; > char *infile = NULL, *outfile = NULL; > int in_fd = 0, out_fd = 0; > int numfiles = 1; > int create = 0, delete = 0, nlink = 1, move = 0; > int rd = 0, wr = 0, wrafter = 0, parent = 0; > int keepopen = 0, drop_caches = 1, sleep_loop = 0; > + int checkmountid = 0; > int bufsz = MAX_HANDLE_SZ; > > if (argc < 2) > usage(); > > - while ((c = getopt(argc, argv, "cludmrwapknhi:o:sz")) != -1) { > + while ((c = getopt(argc, argv, "cludMmrwapknhi:o:sz")) != -1) { > switch (c) { > case 'c': > create = 1; > @@ -172,6 +254,9 @@ int main(int argc, char **argv) > delete = 1; > nlink = 0; > break; > + case 'M': > + checkmountid = 1; > + break; > case 'm': > move = 1; > break; > @@ -307,21 +392,9 @@ int main(int argc, char **argv) > return EXIT_FAILURE; > } > } else { > - handle[i].fh.handle_bytes = bufsz; > - ret = name_to_handle_at(AT_FDCWD, fname, &handle[i].fh, &mount_id, 0); > - if (bufsz < handle[i].fh.handle_bytes) { > - /* Query the filesystem required bufsz and the file handle */ > - if (ret != -1 || errno != EOVERFLOW) { > - fprintf(stderr, "Unexpected result from name_to_handle_at(%s)\n", fname); > - return EXIT_FAILURE; > - } > - ret = name_to_handle_at(AT_FDCWD, fname, &handle[i].fh, &mount_id, 0); > - } > - if (ret < 0) { > - strcat(fname, ": name_to_handle"); > - perror(fname); > + ret = do_name_to_handle_at(fname, &handle[i].fh, bufsz, checkmountid); > + if (ret < 0) > return EXIT_FAILURE; > - } > } > if (keepopen) { > /* Open without close to keep unlinked files around */ > @@ -349,21 +422,9 @@ int main(int argc, char **argv) > return EXIT_FAILURE; > } > } else { > - dir_handle.fh.handle_bytes = bufsz; > - ret = name_to_handle_at(AT_FDCWD, test_dir, &dir_handle.fh, &mount_id, 0); > - if (bufsz < dir_handle.fh.handle_bytes) { > - /* Query the filesystem required bufsz and the file handle */ > - if (ret != -1 || errno != EOVERFLOW) { > - fprintf(stderr, "Unexpected result from name_to_handle_at(%s)\n", dname); > - return EXIT_FAILURE; > - } > - ret = name_to_handle_at(AT_FDCWD, test_dir, &dir_handle.fh, &mount_id, 0); > - } > - if (ret < 0) { > - strcat(dname, ": name_to_handle"); > - perror(dname); > + ret = do_name_to_handle_at(test_dir, &dir_handle.fh, bufsz, checkmountid); > + if (ret < 0) > return EXIT_FAILURE; > - } > } > if (out_fd) { > ret = write(out_fd, (char *)&dir_handle, sizeof(*handle)); > diff --git a/tests/generic/426 b/tests/generic/426 > index 25909f220e1e..df481c58562c 100755 > --- a/tests/generic/426 > +++ b/tests/generic/426 > @@ -51,6 +51,7 @@ test_file_handles $testdir -d > # Check non-stale handles to linked files > create_test_files $testdir > test_file_handles $testdir > +test_file_handles $testdir -M I see no reason to add option -M and add a second invocation. Something I am missing? Thanks, Amir.