From d20d41c7a550559501ff6d45c18a8cb8e7ce2e0d Mon Sep 17 00:00:00 2001
From: "daniel.zatovic" <daniel.zatovic@gmail.com>
Date: Tue, 15 Mar 2022 21:05:46 +0100
Subject: [PATCH] Add log messages, when kernel doesn't support resize.

---
 lib/setup.c          | 13 +++++++++++++
 lib/utils_dm.h       |  1 +
 src/integritysetup.c |  3 +++
 3 files changed, 17 insertions(+)

diff --git a/lib/setup.c b/lib/setup.c
index 75d744cd..7c4519d1 100644
--- a/lib/setup.c
+++ b/lib/setup.c
@@ -2858,6 +2858,8 @@ int crypt_resize(struct crypt_device *cd, const char *name, uint64_t new_size)
 	struct crypt_dm_active_device dmdq, dmd = {};
 	struct dm_target *tgt = &dmdq.segment;
 	struct crypt_params_integrity params = {};
+	uint32_t supported_flags = 0;
+	uint64_t old_size;
 	int r;
 
 	/*
@@ -2921,6 +2923,11 @@ int crypt_resize(struct crypt_device *cd, const char *name, uint64_t new_size)
 	 * superblock.
 	 */
 	if (!new_size && tgt->type == DM_INTEGRITY) {
+		r = INTEGRITY_data_sectors(cd, crypt_metadata_device(cd),
+					   crypt_get_data_offset(cd) * SECTOR_SIZE, &old_size);
+		if (r < 0)
+			return r;
+
 		dmd.size = dmdq.size;
 		dmd.flags = dmdq.flags | CRYPT_ACTIVATE_REFRESH | CRYPT_ACTIVATE_PRIVATE;
 
@@ -2943,6 +2950,9 @@ int crypt_resize(struct crypt_device *cd, const char *name, uint64_t new_size)
 		if (r < 0)
 			return r;
 		log_dbg(cd, "Maximum integrity device size from kernel %lu", new_size);
+
+		if (old_size == new_size && new_size == dmdq.size && !dm_flags(cd, tgt->type, &supported_flags) && !(supported_flags & DM_INTEGRITY_RESIZE_SUPPORTED))
+			log_std(cd, _("WARNING: Maximum size already set or kernel doesn't support resize.\n"));
 	}
 
 	r = device_block_adjust(cd, crypt_data_device(cd), DEV_OK,
@@ -2998,6 +3008,9 @@ int crypt_resize(struct crypt_device *cd, const char *name, uint64_t new_size)
 			r = LUKS2_unmet_requirements(cd, &cd->u.luks2.hdr, 0, 0);
 		if (!r)
 			r = _reload_device(cd, name, &dmd);
+
+		if (r && tgt->type == DM_INTEGRITY && !dm_flags(cd, tgt->type, &supported_flags) && !(supported_flags & DM_INTEGRITY_RESIZE_SUPPORTED))
+			log_err(cd, _("Resize failed, the kernel doesn't support it."));
 	}
 out:
 	dm_targets_free(cd, &dmd);
diff --git a/lib/utils_dm.h b/lib/utils_dm.h
index 825d2299..547a7f9d 100644
--- a/lib/utils_dm.h
+++ b/lib/utils_dm.h
@@ -70,6 +70,7 @@ static inline uint32_t act2dmflags(uint32_t act_flags)
 #define DM_BITLK_ELEPHANT_SUPPORTED (1 << 21) /* Elephant diffuser for BITLK supported */
 #define DM_VERITY_SIGNATURE_SUPPORTED (1 << 22) /* Verity option root_hash_sig_key_desc supported */
 #define DM_INTEGRITY_DISCARDS_SUPPORTED (1 << 23) /* dm-integrity discards/TRIM option is supported */
+#define DM_INTEGRITY_RESIZE_SUPPORTED (1 << 23) /* dm-integrity resize of the integrity device supported (introduced in the same version as discards)*/
 #define DM_VERITY_PANIC_CORRUPTION_SUPPORTED (1 << 24) /* dm-verity panic on corruption  */
 #define DM_CRYPT_NO_WORKQUEUE_SUPPORTED (1 << 25) /* dm-crypt suppot for bypassing workqueues  */
 #define DM_INTEGRITY_FIX_HMAC_SUPPORTED (1 << 26) /* hmac covers also superblock */
diff --git a/src/integritysetup.c b/src/integritysetup.c
index 36bc00fc..7700f770 100644
--- a/src/integritysetup.c
+++ b/src/integritysetup.c
@@ -261,6 +261,9 @@ static int action_resize(void)
 		} else {
 			log_dbg("Setting recalculate flag");
 			r = crypt_activate_by_volume_key(cd, action_argv[0], NULL, 0, CRYPT_ACTIVATE_REFRESH | CRYPT_ACTIVATE_RECALCULATE);
+
+			if (r == -ENOTSUP)
+				log_err(_("Setting recalculate flag is not supported, you may consider using --wipe instead."));
 		}
 	}
 out: