Merge "Merge android-4.4.139 (7ba5557) into msm-4.4"

4 files changed, 40 insertions, 3 deletions

diff --git a/drivers/md/Kconfig b/drivers/md/Kconfig
index 27713412c881..0ad06670fa99 100644
--- a/drivers/md/Kconfig
+++ b/drivers/md/Kconfig
@@ -562,4 +562,24 @@ config DM_ANDROID_VERITY
 	  of the metadata contents are verified against the key included
 	  in the system keyring. Upon success, the underlying verity
 	  target is setup.
+
+config DM_ANDROID_VERITY_AT_MOST_ONCE_DEFAULT_ENABLED
+	bool "Verity will validate blocks at most once"
+   depends on DM_VERITY
+   ---help---
+	  Default enables at_most_once option for dm-verity
+
+	  Verify data blocks only the first time they are read from the
+	  data device, rather than every time.  This reduces the overhead
+	  of dm-verity so that it can be used on systems that are memory
+	  and/or CPU constrained.  However, it provides a reduced level
+	  of security because only offline tampering of the data device's
+	  content will be detected, not online tampering.
+
+	  Hash blocks are still verified each time they are read from the
+	  hash device, since verification of hash blocks is less performance
+	  critical than data blocks, and a hash block will not be verified
+	  any more after all the data blocks it covers have been verified anyway.
+
+	  If unsure, say N.
 endif # MD
diff --git a/drivers/md/dm-thin.c b/drivers/md/dm-thin.c
index 5f1a943d9e81..87454a745e13 100644
--- a/drivers/md/dm-thin.c
+++ b/drivers/md/dm-thin.c
@@ -1299,6 +1299,8 @@ static void schedule_external_copy(struct thin_c *tc, dm_block_t virt_block,
 
 static void set_pool_mode(struct pool *pool, enum pool_mode new_mode);
 
+static void requeue_bios(struct pool *pool);
+
 static void check_for_space(struct pool *pool)
 {
 	int r;
@@ -1311,8 +1313,10 @@ static void check_for_space(struct pool *pool)
 	if (r)
 		return;
 
-	if (nr_free)
+	if (nr_free) {
 		set_pool_mode(pool, PM_WRITE);
+		requeue_bios(pool);
+	}
 }
 
 /*
@@ -1389,7 +1393,10 @@ static int alloc_data_block(struct thin_c *tc, dm_block_t *result)
 
 	r = dm_pool_alloc_data_block(pool->pmd, result);
 	if (r) {
-		metadata_operation_failed(pool, "dm_pool_alloc_data_block", r);
+		if (r == -ENOSPC)
+			set_pool_mode(pool, PM_OUT_OF_DATA_SPACE);
+		else
+			metadata_operation_failed(pool, "dm_pool_alloc_data_block", r);
 		return r;
 	}
 
diff --git a/drivers/md/dm-verity-target.c b/drivers/md/dm-verity-target.c
index ceff074b3b74..d2e3abc182b3 100644
--- a/drivers/md/dm-verity-target.c
+++ b/drivers/md/dm-verity-target.c
@@ -1053,6 +1053,14 @@ int verity_ctr(struct dm_target *ti, unsigned argc, char **argv)
 			goto bad;
 	}
 
+#ifdef CONFIG_DM_ANDROID_VERITY_AT_MOST_ONCE_DEFAULT_ENABLED
+	if (!v->validated_blocks) {
+		r = verity_alloc_most_once(v);
+		if (r)
+			goto bad;
+	}
+#endif
+
 	v->hash_per_block_bits =
 		__fls((1 << v->hash_dev_block_bits) / v->digest_size);
 
diff --git a/drivers/md/md.c b/drivers/md/md.c
index 3a9685fe115c..c25534e10f43 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -2690,7 +2690,8 @@ state_store(struct md_rdev *rdev, const char *buf, size_t len)
 			err = 0;
 		}
 	} else if (cmd_match(buf, "re-add")) {
-		if (test_bit(Faulty, &rdev->flags) && (rdev->raid_disk == -1)) {
+		if (test_bit(Faulty, &rdev->flags) && (rdev->raid_disk == -1) &&
+			rdev->saved_raid_disk >= 0) {
 			/* clear_bit is performed _after_ all the devices
 			 * have their local Faulty bit cleared. If any writes
 			 * happen in the meantime in the local node, they
@@ -8153,6 +8154,7 @@ static int remove_and_add_spares(struct mddev *mddev,
 			if (mddev->pers->hot_remove_disk(
 				    mddev, rdev) == 0) {
 				sysfs_unlink_rdev(mddev, rdev);
+				rdev->saved_raid_disk = rdev->raid_disk;
 				rdev->raid_disk = -1;
 				removed++;
 			}