dm: add support for secure erase forwarding

Set QUEUE_FLAG_SECERASE in DM device's queue_flags if a DM table's
data devices support secure erase.

Also, add support for secure erase to both the linear and striped
targets.

Signed-off-by: Denis Semakin <d.semakin@omprussia.ru>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

5 files changed, 52 insertions, 0 deletions

diff --git a/drivers/md/dm-linear.c b/drivers/md/dm-linear.c
index d5f8eff7c11d..ff751b00aacd 100644
--- a/drivers/md/dm-linear.c
+++ b/drivers/md/dm-linear.c
@@ -59,6 +59,7 @@ static int linear_ctr(struct dm_target *ti, unsigned int argc, char **argv)
 
         ti->num_flush_bios = 1;
         ti->num_discard_bios = 1;
+        ti->num_secure_erase_bios = 1;
         ti->num_write_same_bios = 1;
         ti->num_write_zeroes_bios = 1;
         ti->private = lc;
diff --git a/drivers/md/dm-stripe.c b/drivers/md/dm-stripe.c
index cd209e8902a6..bb907cb3e60d 100644
--- a/drivers/md/dm-stripe.c
+++ b/drivers/md/dm-stripe.c
@@ -169,6 +169,7 @@ static int stripe_ctr(struct dm_target *ti, unsigned int argc, char **argv)
 
         ti->num_flush_bios = stripes;
         ti->num_discard_bios = stripes;
+        ti->num_secure_erase_bios = stripes;
         ti->num_write_same_bios = stripes;
         ti->num_write_zeroes_bios = stripes;
 
@@ -295,6 +296,7 @@ static int stripe_map(struct dm_target *ti, struct bio *bio)
                 return DM_MAPIO_REMAPPED;
         }
         if (unlikely(bio_op(bio) == REQ_OP_DISCARD) ||
+            unlikely(bio_op(bio) == REQ_OP_SECURE_ERASE) ||
             unlikely(bio_op(bio) == REQ_OP_WRITE_ZEROES) ||
             unlikely(bio_op(bio) == REQ_OP_WRITE_SAME)) {
                 target_bio_nr = dm_bio_get_target_bio_nr(bio);
diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c
index 7eb3e2a3c07d..f20fbc96a805 100644
--- a/drivers/md/dm-table.c
+++ b/drivers/md/dm-table.c
@@ -1846,6 +1846,34 @@ static bool dm_table_supports_discards(struct dm_table *t)
         return true;
 }
 
+static int device_not_secure_erase_capable(struct dm_target *ti,
+                                           struct dm_dev *dev, sector_t start,
+                                           sector_t len, void *data)
+{
+        struct request_queue *q = bdev_get_queue(dev->bdev);
+
+        return q && !blk_queue_secure_erase(q);
+}
+
+static bool dm_table_supports_secure_erase(struct dm_table *t)
+{
+        struct dm_target *ti;
+        unsigned int i;
+
+        for (i = 0; i < dm_table_get_num_targets(t); i++) {
+                ti = dm_table_get_target(t, i);
+
+                if (!ti->num_secure_erase_bios)
+                        return false;
+
+                if (!ti->type->iterate_devices ||
+                    ti->type->iterate_devices(ti, device_not_secure_erase_capable, NULL))
+                        return false;
+        }
+
+        return true;
+}
+
 void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q,
                                struct queue_limits *limits)
 {
@@ -1867,6 +1895,9 @@ void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q,
         } else
                 queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, q);
 
+        if (dm_table_supports_secure_erase(t))
+                queue_flag_set_unlocked(QUEUE_FLAG_SECERASE, q);
+
         if (dm_table_supports_flush(t, (1UL << QUEUE_FLAG_WC))) {
                 wc = true;
                 if (dm_table_supports_flush(t, (1UL << QUEUE_FLAG_FUA)))
diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index 038c7572fdd4..3b3cbd1a1659 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -1414,6 +1414,11 @@ static unsigned get_num_discard_bios(struct dm_target *ti)
         return ti->num_discard_bios;
 }
 
+static unsigned get_num_secure_erase_bios(struct dm_target *ti)
+{
+        return ti->num_secure_erase_bios;
+}
+
 static unsigned get_num_write_same_bios(struct dm_target *ti)
 {
         return ti->num_write_same_bios;
@@ -1467,6 +1472,11 @@ static int __send_discard(struct clone_info *ci, struct dm_target *ti)
                                            is_split_required_for_discard);
 }
 
+static int __send_secure_erase(struct clone_info *ci, struct dm_target *ti)
+{
+        return __send_changing_extent_only(ci, ti, get_num_secure_erase_bios, NULL);
+}
+
 static int __send_write_same(struct clone_info *ci, struct dm_target *ti)
 {
         return __send_changing_extent_only(ci, ti, get_num_write_same_bios, NULL);
@@ -1484,6 +1494,8 @@ static bool __process_abnormal_io(struct clone_info *ci, struct dm_target *ti,
 
         if (bio_op(bio) == REQ_OP_DISCARD)
                 *result = __send_discard(ci, ti);
+        else if (bio_op(bio) == REQ_OP_SECURE_ERASE)
+                *result = __send_secure_erase(ci, ti);
         else if (bio_op(bio) == REQ_OP_WRITE_SAME)
                 *result = __send_write_same(ci, ti);
         else if (bio_op(bio) == REQ_OP_WRITE_ZEROES)
diff --git a/include/linux/device-mapper.h b/include/linux/device-mapper.h
index 1e2426c18eb4..019e2efc6c25 100644
--- a/include/linux/device-mapper.h
+++ b/include/linux/device-mapper.h
@@ -268,6 +268,12 @@ struct dm_target {
         unsigned num_discard_bios;
 
         /*
+         * The number of secure erase bios that will be submitted to the target.
+         * The bio number can be accessed with dm_bio_get_target_bio_nr.
+         */
+        unsigned num_secure_erase_bios;
+
+        /*
          * The number of WRITE SAME bios that will be submitted to the target.
          * The bio number can be accessed with dm_bio_get_target_bio_nr.
          */