diff --git a/block/blk-integrity.c b/block/blk-integrity.c
index 54bcba6c02a75ed87af935c49d4428f18eb6a615..129b9e209a3b46dcf06ab36c0629e632e9b75035 100644
--- a/block/blk-integrity.c
+++ b/block/blk-integrity.c
@@ -30,6 +30,8 @@
static struct kmem_cache *integrity_cachep;
+static const char *bi_unsupported_name = "unsupported";
+
/**
* blk_rq_count_integrity_sg - Count number of integrity scatterlist elements
* @q: request queue
@@ -358,6 +360,14 @@ static struct kobj_type integrity_ktype = {
.release = blk_integrity_release,
};
+bool blk_integrity_is_initialized(struct gendisk *disk)
+{
+ struct blk_integrity *bi = blk_get_integrity(disk);
+
+ return (bi && bi->name && strcmp(bi->name, bi_unsupported_name) != 0);
+}
+EXPORT_SYMBOL(blk_integrity_is_initialized);
+
/**
* blk_integrity_register - Register a gendisk as being integrity-capable
* @disk: struct gendisk pointer to make integrity-aware
@@ -407,7 +417,7 @@ int blk_integrity_register(struct gendisk *disk, struct blk_integrity *template)
bi->get_tag_fn = template->get_tag_fn;
bi->tag_size = template->tag_size;
} else
- bi->name = "unsupported";
+ bi->name = bi_unsupported_name;
return 0;
}
diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c
index 416d4e258df6df536d2cd7d38795e8e58b94efbc..cb8380c9767fd3d5bb815d7fec4a46308b0270c5 100644
--- a/drivers/md/dm-table.c
+++ b/drivers/md/dm-table.c
@@ -926,21 +926,81 @@ static int dm_table_build_index(struct dm_table *t)
return r;
}
+/*
+ * Get a disk whose integrity profile reflects the table's profile.
+ * If %match_all is true, all devices' profiles must match.
+ * If %match_all is false, all devices must at least have an
+ * allocated integrity profile; but uninitialized is ok.
+ * Returns NULL if integrity support was inconsistent or unavailable.
+ */
+static struct gendisk * dm_table_get_integrity_disk(struct dm_table *t,
+ bool match_all)
+{
+ struct list_head *devices = dm_table_get_devices(t);
+ struct dm_dev_internal *dd = NULL;
+ struct gendisk *prev_disk = NULL, *template_disk = NULL;
+
+ list_for_each_entry(dd, devices, list) {
+ template_disk = dd->dm_dev.bdev->bd_disk;
+ if (!blk_get_integrity(template_disk))
+ goto no_integrity;
+ if (!match_all && !blk_integrity_is_initialized(template_disk))
+ continue; /* skip uninitialized profiles */
+ else if (prev_disk &&
+ blk_integrity_compare(prev_disk, template_disk) < 0)
+ goto no_integrity;
+ prev_disk = template_disk;
+ }
+
+ return template_disk;
+
+no_integrity:
+ if (prev_disk)
+ DMWARN("%s: integrity not set: %s and %s profile mismatch",
+ dm_device_name(t->md),
+ prev_disk->disk_name,
+ template_disk->disk_name);
+ return NULL;
+}
+
/*
* Register the mapped device for blk_integrity support if
- * the underlying devices support it.
+ * the underlying devices have an integrity profile. But all devices
+ * may not have matching profiles (checking all devices isn't reliable
+ * during table load because this table may use other DM device(s) which
+ * must be resumed before they will have an initialized integity profile).
+ * Stacked DM devices force a 2 stage integrity profile validation:
+ * 1 - during load, validate all initialized integrity profiles match
+ * 2 - during resume, validate all integrity profiles match
*/
static int dm_table_prealloc_integrity(struct dm_table *t, struct mapped_device *md)
{
- struct list_head *devices = dm_table_get_devices(t);
- struct dm_dev_internal *dd;
+ struct gendisk *template_disk = NULL;
- list_for_each_entry(dd, devices, list)
- if (bdev_get_integrity(dd->dm_dev.bdev)) {
- t->integrity_supported = 1;
- return blk_integrity_register(dm_disk(md), NULL);
- }
+ template_disk = dm_table_get_integrity_disk(t, false);
+ if (!template_disk)
+ return 0;
+ if (!blk_integrity_is_initialized(dm_disk(md))) {
+ t->integrity_supported = 1;
+ return blk_integrity_register(dm_disk(md), NULL);
+ }
+
+ /*
+ * If DM device already has an initalized integrity
+ * profile the new profile should not conflict.
+ */
+ if (blk_integrity_is_initialized(template_disk) &&
+ blk_integrity_compare(dm_disk(md), template_disk) < 0) {
+ DMWARN("%s: conflict with existing integrity profile: "
+ "%s profile mismatch",
+ dm_device_name(t->md),
+ template_disk->disk_name);
+ return 1;
+ }
+
+ /* Preserve existing initialized integrity profile */
+ t->integrity_supported = 1;
return 0;
}
@@ -1094,41 +1154,27 @@ int dm_calculate_queue_limits(struct dm_table *table,
/*
* Set the integrity profile for this device if all devices used have
- * matching profiles.
+ * matching profiles. We're quite deep in the resume path but still
+ * don't know if all devices (particularly DM devices this device
+ * may be stacked on) have matching profiles. Even if the profiles
+ * don't match we have no way to fail (to resume) at this point.
*/
static void dm_table_set_integrity(struct dm_table *t)
{
- struct list_head *devices = dm_table_get_devices(t);
- struct dm_dev_internal *prev = NULL, *dd = NULL;
+ struct gendisk *template_disk = NULL;
if (!blk_get_integrity(dm_disk(t->md)))
return;
- list_for_each_entry(dd, devices, list) {
- if (prev &&
- blk_integrity_compare(prev->dm_dev.bdev->bd_disk,
- dd->dm_dev.bdev->bd_disk) < 0) {
- DMWARN("%s: integrity not set: %s and %s mismatch",
- dm_device_name(t->md),
- prev->dm_dev.bdev->bd_disk->disk_name,
- dd->dm_dev.bdev->bd_disk->disk_name);
- goto no_integrity;
- }
- prev = dd;
+ template_disk = dm_table_get_integrity_disk(t, true);
+ if (!template_disk &&
+ blk_integrity_is_initialized(dm_disk(t->md))) {
+ DMWARN("%s: device no longer has a valid integrity profile",
+ dm_device_name(t->md));
+ return;
}
-
- if (!prev || !bdev_get_integrity(prev->dm_dev.bdev))
- goto no_integrity;
-
blk_integrity_register(dm_disk(t->md),
- bdev_get_integrity(prev->dm_dev.bdev));
-
- return;
-
-no_integrity:
- blk_integrity_register(dm_disk(t->md), NULL);
-
- return;
+ blk_get_integrity(template_disk));
}
void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q,
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 16a902f099ac0ee7b1f64c4322c6255a82aa0e09..32176cc8e715e450a40e7ba24d39010603cf75f3 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -1206,6 +1206,7 @@ struct blk_integrity {
struct kobject kobj;
};
+extern bool blk_integrity_is_initialized(struct gendisk *);
extern int blk_integrity_register(struct gendisk *, struct blk_integrity *);
extern void blk_integrity_unregister(struct gendisk *);
extern int blk_integrity_compare(struct gendisk *, struct gendisk *);
@@ -1262,6 +1263,7 @@ queue_max_integrity_segments(struct request_queue *q)
#define queue_max_integrity_segments(a) (0)
#define blk_integrity_merge_rq(a, b, c) (0)
#define blk_integrity_merge_bio(a, b, c) (0)
+#define blk_integrity_is_initialized(a) (0)
#endif /* CONFIG_BLK_DEV_INTEGRITY */