Allow dm-integrity to be used for raid images

dm-integrity stores checksums of the data written to an
LV, and returns an error if data read from the LV does
not match the previously saved checksum.  When used on
raid images, dm-raid will correct the error by reading
the block from another image, and the device user sees
no error.  The integrity metadata (checksums) are stored
on an internal LV allocated by lvm for each linear image.
The internal LV is allocated on the same PV as the image.

Create a raid LV with an integrity layer over each
raid image (for raid levels 1,4,5,6,10):

lvcreate --type raidN --raidintegrity y [options]

Add an integrity layer to images of an existing raid LV:

lvconvert --raidintegrity y LV

Remove the integrity layer from images of a raid LV:

lvconvert --raidintegrity n LV

Settings

Use --raidintegritymode journal|bitmap (journal is default)
to configure the method used by dm-integrity to ensure
crash consistency.

Initialization

When integrity is added to an LV, the kernel needs to
initialize the integrity metadata/checksums for all blocks
in the LV.  The data corruption checking performed by
dm-integrity will only operate on areas of the LV that
are already initialized.  The progress of integrity
initialization is reported by the "syncpercent" LV
reporting field (and under the Cpy%Sync lvs column.)

Example: create a raid1 LV with integrity:

$ lvcreate --type raid1 -m1 --raidintegrity y -n rr -L1G foo
  Creating integrity metadata LV rr_rimage_0_imeta with size 12.00 MiB.
  Logical volume "rr_rimage_0_imeta" created.
  Creating integrity metadata LV rr_rimage_1_imeta with size 12.00 MiB.
  Logical volume "rr_rimage_1_imeta" created.
  Logical volume "rr" created.
$ lvs -a foo
  LV                  VG  Attr       LSize  Origin              Cpy%Sync
  rr                  foo rwi-a-r---  1.00g                     4.93
  [rr_rimage_0]       foo gwi-aor---  1.00g [rr_rimage_0_iorig] 41.02
  [rr_rimage_0_imeta] foo ewi-ao---- 12.00m
  [rr_rimage_0_iorig] foo -wi-ao----  1.00g
  [rr_rimage_1]       foo gwi-aor---  1.00g [rr_rimage_1_iorig] 39.45
  [rr_rimage_1_imeta] foo ewi-ao---- 12.00m
  [rr_rimage_1_iorig] foo -wi-ao----  1.00g
  [rr_rmeta_0]        foo ewi-aor---  4.00m
  [rr_rmeta_1]        foo ewi-aor---  4.00m

1 files changed, 343 insertions, 0 deletions

diff --git a/lib/integrity/integrity.c b/lib/integrity/integrity.c
new file mode 100644
index 000000000..d5ad86b63
--- /dev/null
+++ b/lib/integrity/integrity.c
@@ -0,0 +1,343 @@
+/*
+ * Copyright (C) 2013-2016 Red Hat, Inc. All rights reserved.
+ *
+ * This file is part of LVM2.
+ *
+ * This copyrighted material is made available to anyone wishing to use,
+ * modify, copy, or redistribute it subject to the terms and conditions
+ * of the GNU Lesser General Public License v.2.1.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "base/memory/zalloc.h"
+#include "lib/misc/lib.h"
+#include "lib/commands/toolcontext.h"
+#include "lib/metadata/segtype.h"
+#include "lib/display/display.h"
+#include "lib/format_text/text_export.h"
+#include "lib/config/config.h"
+#include "lib/datastruct/str_list.h"
+#include "lib/misc/lvm-string.h"
+#include "lib/activate/activate.h"
+#include "lib/metadata/metadata.h"
+#include "lib/metadata/lv_alloc.h"
+#include "lib/config/defaults.h"
+
+#define SEG_LOG_ERROR(t, p...) \
+        log_error(t " segment %s of logical volume %s.", ## p,	\
+                  dm_config_parent_name(sn), seg->lv->name), 0;
+
+static void _integrity_display(const struct lv_segment *seg)
+{
+	/* TODO: lvdisplay segments */
+}
+
+static int _integrity_text_import(struct lv_segment *seg,
+				   const struct dm_config_node *sn,
+				   struct dm_hash_table *pv_hash __attribute__((unused)))
+{
+	struct integrity_settings *set;
+	struct logical_volume *origin_lv = NULL;
+	struct logical_volume *meta_lv = NULL;
+	const char *origin_name = NULL;
+	const char *meta_dev = NULL;
+	const char *mode = NULL;
+	const char *hash = NULL;
+
+	memset(&seg->integrity_settings, 0, sizeof(struct integrity_settings));
+	set = &seg->integrity_settings;
+
+	/* origin always set */
+
+	if (!dm_config_has_node(sn, "origin"))
+		return SEG_LOG_ERROR("origin not specified in");
+
+	if (!dm_config_get_str(sn, "origin", &origin_name))
+		return SEG_LOG_ERROR("origin must be a string in");
+
+	if (!(origin_lv = find_lv(seg->lv->vg, origin_name)))
+		return SEG_LOG_ERROR("Unknown LV specified for integrity origin %s in", origin_name);
+
+	if (!set_lv_segment_area_lv(seg, 0, origin_lv, 0, 0))
+		return_0;
+
+	/* data_sectors always set */
+
+	if (!dm_config_get_uint64(sn, "data_sectors", &seg->integrity_data_sectors))
+		return SEG_LOG_ERROR("integrity data_sectors must be set in");
+
+	/* mode always set */
+
+	if (!dm_config_get_str(sn, "mode", &mode))
+		return SEG_LOG_ERROR("integrity mode must be set in");
+
+	if (strlen(mode) > 7)
+		return SEG_LOG_ERROR("integrity mode invalid in");
+
+	strncpy(set->mode, mode, 7);
+
+	/* tag_size always set */
+
+	if (!dm_config_get_uint32(sn, "tag_size", &set->tag_size))
+		return SEG_LOG_ERROR("integrity tag_size must be set in");
+
+	/* block_size always set */
+
+	if (!dm_config_get_uint32(sn, "block_size", &set->block_size))
+		return SEG_LOG_ERROR("integrity block_size invalid in");
+
+	/* internal_hash always set */
+
+	if (!dm_config_get_str(sn, "internal_hash", &hash))
+		return SEG_LOG_ERROR("integrity internal_hash must be set in");
+
+	if (!(set->internal_hash = dm_pool_strdup(seg->lv->vg->vgmem, hash)))
+		return SEG_LOG_ERROR("integrity internal_hash failed to be set in");
+
+	/* meta_dev optional */
+
+	if (dm_config_has_node(sn, "meta_dev")) {
+		if (!dm_config_get_str(sn, "meta_dev", &meta_dev))
+			return SEG_LOG_ERROR("meta_dev must be a string in");
+
+		if (!(meta_lv = find_lv(seg->lv->vg, meta_dev)))
+			return SEG_LOG_ERROR("Unknown logical volume %s specified for integrity in", meta_dev);
+	}
+
+	if (dm_config_has_node(sn, "recalculate")) {
+		if (!dm_config_get_uint32(sn, "recalculate", &seg->integrity_recalculate))
+			return SEG_LOG_ERROR("integrity recalculate error in");
+	}
+
+	/* the rest are optional */
+
+	if (dm_config_has_node(sn, "journal_sectors")) {
+		if (!dm_config_get_uint32(sn, "journal_sectors", &set->journal_sectors))
+			return SEG_LOG_ERROR("Unknown integrity_setting in");
+		set->journal_sectors_set = 1;
+	}
+
+	if (dm_config_has_node(sn, "interleave_sectors")) {
+		if (!dm_config_get_uint32(sn, "interleave_sectors", &set->interleave_sectors))
+			return SEG_LOG_ERROR("Unknown integrity_setting in");
+		set->interleave_sectors_set = 1;
+	}
+
+	if (dm_config_has_node(sn, "buffer_sectors")) {
+		if (!dm_config_get_uint32(sn, "buffer_sectors", &set->buffer_sectors))
+			return SEG_LOG_ERROR("Unknown integrity_setting in");
+		set->buffer_sectors_set = 1;
+	}
+
+	if (dm_config_has_node(sn, "journal_watermark")) {
+		if (!dm_config_get_uint32(sn, "journal_watermark", &set->journal_watermark))
+			return SEG_LOG_ERROR("Unknown integrity_setting in");
+		set->journal_watermark_set = 1;
+	}
+
+	if (dm_config_has_node(sn, "commit_time")) {
+		if (!dm_config_get_uint32(sn, "commit_time", &set->commit_time))
+			return SEG_LOG_ERROR("Unknown integrity_setting in");
+		set->commit_time_set = 1;
+	}
+
+	if (dm_config_has_node(sn, "bitmap_flush_interval")) {
+		if (!dm_config_get_uint32(sn, "bitmap_flush_interval", &set->bitmap_flush_interval))
+			return SEG_LOG_ERROR("Unknown integrity_setting in");
+		set->bitmap_flush_interval_set = 1;
+	}
+
+	if (dm_config_has_node(sn, "sectors_per_bit")) {
+		if (!dm_config_get_uint64(sn, "sectors_per_bit", &set->sectors_per_bit))
+			return SEG_LOG_ERROR("Unknown integrity_setting in");
+		set->sectors_per_bit_set = 1;
+	}
+
+	seg->origin = origin_lv;
+	seg->integrity_meta_dev = meta_lv;
+	seg->lv->status |= INTEGRITY;
+
+	if (meta_lv)
+		meta_lv->status |= INTEGRITY_METADATA;
+
+	if (meta_lv && !add_seg_to_segs_using_this_lv(meta_lv, seg))
+		return_0;
+
+	return 1;
+}
+
+static int _integrity_text_import_area_count(const struct dm_config_node *sn,
+					      uint32_t *area_count)
+{
+	*area_count = 1;
+
+	return 1;
+}
+
+static int _integrity_text_export(const struct lv_segment *seg,
+				   struct formatter *f)
+{
+	const struct integrity_settings *set = &seg->integrity_settings;
+
+	outf(f, "origin = \"%s\"", seg_lv(seg, 0)->name);
+	outf(f, "data_sectors = %llu", (unsigned long long)seg->integrity_data_sectors);
+
+	outf(f, "mode = \"%s\"", set->mode);
+	outf(f, "tag_size = %u", set->tag_size);
+	outf(f, "block_size = %u", set->block_size);
+	outf(f, "internal_hash = \"%s\"", set->internal_hash);
+
+	if (seg->integrity_meta_dev)
+		outf(f, "meta_dev = \"%s\"", seg->integrity_meta_dev->name);
+
+	if (seg->integrity_recalculate)
+		outf(f, "recalculate = %u", seg->integrity_recalculate);
+
+	if (set->journal_sectors_set)
+		outf(f, "journal_sectors = %u", set->journal_sectors);
+
+	if (set->interleave_sectors_set)
+		outf(f, "interleave_sectors = %u", set->interleave_sectors);
+
+	if (set->buffer_sectors_set)
+		outf(f, "buffer_sectors = %u", set->buffer_sectors);
+
+	if (set->journal_watermark_set)
+		outf(f, "journal_watermark = %u", set->journal_watermark);
+
+	if (set->commit_time_set)
+		outf(f, "commit_time = %u", set->commit_time);
+
+	if (set->bitmap_flush_interval)
+		outf(f, "bitmap_flush_interval = %u", set->bitmap_flush_interval);
+
+	if (set->sectors_per_bit)
+		outf(f, "sectors_per_bit = %llu", (unsigned long long)set->sectors_per_bit);
+
+	return 1;
+}
+
+static void _destroy(struct segment_type *segtype)
+{
+	free((void *) segtype);
+}
+
+#ifdef DEVMAPPER_SUPPORT
+
+static int _target_present(struct cmd_context *cmd,
+			   const struct lv_segment *seg __attribute__((unused)),
+			   unsigned *attributes __attribute__((unused)))
+{
+	static int _integrity_checked = 0;
+	static int _integrity_present = 0;
+	uint32_t maj, min, patchlevel;
+
+	if (!activation())
+		return 0;
+
+	if (!_integrity_checked) {
+		_integrity_checked = 1;
+		_integrity_present =  target_present(cmd, TARGET_NAME_INTEGRITY, 1);
+
+		if (!target_version(TARGET_NAME_INTEGRITY, &maj, &min, &patchlevel))
+			return 0;
+
+		if (maj < 1 || min < 6) {
+			log_error("Integrity target version older than minimum 1.6.0");
+			return 0;
+		}
+	}
+
+	return _integrity_present;
+}
+
+static int _modules_needed(struct dm_pool *mem,
+			   const struct lv_segment *seg __attribute__((unused)),
+			   struct dm_list *modules)
+{
+	if (!str_list_add(mem, modules, MODULE_NAME_INTEGRITY)) {
+		log_error("String list allocation failed for integrity module.");
+		return 0;
+	}
+
+	return 1;
+}
+#endif /* DEVMAPPER_SUPPORT */
+
+#ifdef DEVMAPPER_SUPPORT
+static int _integrity_add_target_line(struct dev_manager *dm,
+				 struct dm_pool *mem,
+				 struct cmd_context *cmd __attribute__((unused)),
+				 void **target_state __attribute__((unused)),
+				 struct lv_segment *seg,
+				 const struct lv_activate_opts *laopts,
+				 struct dm_tree_node *node, uint64_t len,
+				 uint32_t *pvmove_mirror_count __attribute__((unused)))
+{
+	char *origin_uuid;
+	char *meta_uuid = NULL;
+
+	if (!seg_is_integrity(seg)) {
+		log_error(INTERNAL_ERROR "Passed segment is not integrity.");
+		return 0;
+	}
+
+	if (!(origin_uuid = build_dm_uuid(mem, seg_lv(seg, 0), NULL)))
+		return_0;
+
+	if (seg->integrity_meta_dev) {
+		if (!(meta_uuid = build_dm_uuid(mem, seg->integrity_meta_dev, NULL)))
+			return_0;
+	}
+
+	if (!seg->integrity_data_sectors) {
+		log_error("_integrity_add_target_line zero size");
+		return_0;
+	}
+
+	if (!dm_tree_node_add_integrity_target(node, seg->integrity_data_sectors,
+					       origin_uuid, meta_uuid,
+					       &seg->integrity_settings,
+					       seg->integrity_recalculate))
+		return_0;
+
+	return 1;
+}
+#endif /* DEVMAPPER_SUPPORT */
+
+static struct segtype_handler _integrity_ops = {
+	.display = _integrity_display,
+	.text_import = _integrity_text_import,
+	.text_import_area_count = _integrity_text_import_area_count,
+	.text_export = _integrity_text_export,
+#ifdef DEVMAPPER_SUPPORT
+	.add_target_line = _integrity_add_target_line,
+	.target_present = _target_present,
+	.modules_needed = _modules_needed,
+#endif
+	.destroy = _destroy,
+};
+
+int init_integrity_segtypes(struct cmd_context *cmd,
+			struct segtype_library *seglib)
+{
+	struct segment_type *segtype = zalloc(sizeof(*segtype));
+
+	if (!segtype) {
+		log_error("Failed to allocate memory for integrity segtype");
+		return 0;
+	}
+
+	segtype->name = SEG_TYPE_NAME_INTEGRITY;
+	segtype->flags = SEG_INTEGRITY;
+	segtype->ops = &_integrity_ops;
+
+	if (!lvm_register_segtype(seglib, segtype))
+		return_0;
+	log_very_verbose("Initialised segtype: %s", segtype->name);
+
+	return 1;
+}