If there is an error half way through KHO memory preservation, we should rollback and unpreserve everything that is partially preserved.
Co-developed-by: Mike Rapoport (Microsoft) <[email protected]> Signed-off-by: Mike Rapoport (Microsoft) <[email protected]> Signed-off-by: Pasha Tatashin <[email protected]> --- lib/test_kho.c | 103 +++++++++++++++++++++++++++++++++++-------------- 1 file changed, 73 insertions(+), 30 deletions(-) diff --git a/lib/test_kho.c b/lib/test_kho.c index 9f7cfa6ac855..025ea251a186 100644 --- a/lib/test_kho.c +++ b/lib/test_kho.c @@ -33,17 +33,28 @@ struct kho_test_state { unsigned int nr_folios; struct folio **folios; phys_addr_t *folios_info; + struct kho_vmalloc folios_info_phys; + int nr_folios_preserved; struct folio *fdt; __wsum csum; }; static struct kho_test_state kho_test_state; -static int kho_test_save_data(struct kho_test_state *state, void *fdt) +static void kho_test_unpreserve_data(struct kho_test_state *state) +{ + for (int i = 0; i < state->nr_folios_preserved; i++) + kho_unpreserve_folio(state->folios[i]); + + kho_unpreserve_vmalloc(&state->folios_info_phys); + vfree(state->folios_info); +} + +static int kho_test_preserve_data(struct kho_test_state *state) { - phys_addr_t *folios_info __free(kvfree) = NULL; struct kho_vmalloc folios_info_phys; - int err = 0; + phys_addr_t *folios_info; + int err; folios_info = vmalloc_array(state->nr_folios, sizeof(*folios_info)); if (!folios_info) @@ -51,64 +62,98 @@ static int kho_test_save_data(struct kho_test_state *state, void *fdt) err = kho_preserve_vmalloc(folios_info, &folios_info_phys); if (err) - return err; + goto err_free_info; + + state->folios_info_phys = folios_info_phys; + state->folios_info = folios_info; for (int i = 0; i < state->nr_folios; i++) { struct folio *folio = state->folios[i]; unsigned int order = folio_order(folio); folios_info[i] = virt_to_phys(folio_address(folio)) | order; - err = kho_preserve_folio(folio); if (err) - break; + goto err_unpreserve; + state->nr_folios_preserved++; } + return 0; + +err_unpreserve: + /* + * kho_test_unpreserve_data frees folio_info, bail out immediately to + * avoid double free + */ + kho_test_unpreserve_data(state); + return err; + +err_free_info: + vfree(folios_info); + return err; +} + +static int kho_test_prepare_fdt(struct kho_test_state *state, ssize_t fdt_size) +{ + const char compatible[] = KHO_TEST_COMPAT; + unsigned int magic = KHO_TEST_MAGIC; + void *fdt = folio_address(state->fdt); + int err; + + err = fdt_create(fdt, fdt_size); + err |= fdt_finish_reservemap(fdt); + err |= fdt_begin_node(fdt, ""); + err |= fdt_property(fdt, "compatible", compatible, sizeof(compatible)); + err |= fdt_property(fdt, "magic", &magic, sizeof(magic)); + err |= fdt_begin_node(fdt, "data"); err |= fdt_property(fdt, "nr_folios", &state->nr_folios, sizeof(state->nr_folios)); - err |= fdt_property(fdt, "folios_info", &folios_info_phys, - sizeof(folios_info_phys)); + err |= fdt_property(fdt, "folios_info", &state->folios_info_phys, + sizeof(state->folios_info_phys)); err |= fdt_property(fdt, "csum", &state->csum, sizeof(state->csum)); err |= fdt_end_node(fdt); - if (!err) - state->folios_info = no_free_ptr(folios_info); + err |= fdt_end_node(fdt); + err |= fdt_finish(fdt); return err; } -static int kho_test_prepare_fdt(struct kho_test_state *state) +static int kho_test_preserve(struct kho_test_state *state) { - const char compatible[] = KHO_TEST_COMPAT; - unsigned int magic = KHO_TEST_MAGIC; ssize_t fdt_size; - int err = 0; - void *fdt; + int err; fdt_size = state->nr_folios * sizeof(phys_addr_t) + PAGE_SIZE; state->fdt = folio_alloc(GFP_KERNEL, get_order(fdt_size)); if (!state->fdt) return -ENOMEM; - fdt = folio_address(state->fdt); - - err |= kho_preserve_folio(state->fdt); - err |= fdt_create(fdt, fdt_size); - err |= fdt_finish_reservemap(fdt); + err = kho_preserve_folio(state->fdt); + if (err) + goto err_free_fdt; - err |= fdt_begin_node(fdt, ""); - err |= fdt_property(fdt, "compatible", compatible, sizeof(compatible)); - err |= fdt_property(fdt, "magic", &magic, sizeof(magic)); - err |= kho_test_save_data(state, fdt); - err |= fdt_end_node(fdt); + err = kho_test_preserve_data(state); + if (err) + goto err_unpreserve_fdt; - err |= fdt_finish(fdt); + err = kho_test_prepare_fdt(state, fdt_size); + if (err) + goto err_unpreserve_data; err = kho_add_subtree(KHO_TEST_FDT, folio_address(state->fdt)); if (err) - folio_put(state->fdt); + goto err_unpreserve_data; + return 0; + +err_unpreserve_data: + kho_test_unpreserve_data(state); +err_unpreserve_fdt: + kho_unpreserve_folio(state->fdt); +err_free_fdt: + folio_put(state->fdt); return err; } @@ -174,14 +219,12 @@ static int kho_test_save(void) if (err) goto err_free_folios; - err = kho_test_prepare_fdt(state); + err = kho_test_preserve(state); if (err) goto err_free_folios; return 0; -err_free_fdt: - folio_put(state->fdt); err_free_folios: kvfree(folios); return err; -- 2.51.1.930.gacf6e81ea2-goog
