Merge tag 'dm-3.8-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-dm

Pull dm update from Alasdair G Kergon:
 "Miscellaneous device-mapper fixes, cleanups and performance
  improvements.

  Of particular note:
   - Disable broken WRITE SAME support in all targets except linear and
     striped.  Use it when kcopyd is zeroing blocks.
   - Remove several mempools from targets by moving the data into the
     bio's new front_pad area(which dm calls 'per_bio_data').
   - Fix a race in thin provisioning if discards are misused.
   - Prevent userspace from interfering with the ioctl parameters and
     use kmalloc for the data buffer if it's small instead of vmalloc.
   - Throttle some annoying error messages when I/O fails."

* tag 'dm-3.8-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-dm: (36 commits)
  dm stripe: add WRITE SAME support
  dm: remove map_info
  dm snapshot: do not use map_context
  dm thin: dont use map_context
  dm raid1: dont use map_context
  dm flakey: dont use map_context
  dm raid1: rename read_record to bio_record
  dm: move target request nr to dm_target_io
  dm snapshot: use per_bio_data
  dm verity: use per_bio_data
  dm raid1: use per_bio_data
  dm: introduce per_bio_data
  dm kcopyd: add WRITE SAME support to dm_kcopyd_zero
  dm linear: add WRITE SAME support
  dm: add WRITE SAME support
  dm: prepare to support WRITE SAME
  dm ioctl: use kmalloc if possible
  dm ioctl: remove PF_MEMALLOC
  dm persistent data: improve improve space map block alloc failure message
  dm thin: use DMERR_LIMIT for errors
  ...

30 files changed, 522 insertions, 443 deletions

diff --git a/drivers/md/dm-bio-prison.c b/drivers/md/dm-bio-prison.c
index e4e841567459..aefb78e3cbf9 100644
--- a/drivers/md/dm-bio-prison.c
+++ b/drivers/md/dm-bio-prison.c
@@ -208,31 +208,6 @@ void dm_cell_release(struct dm_bio_prison_cell *cell, struct bio_list *bios)
 EXPORT_SYMBOL_GPL(dm_cell_release);
 
 /*
- * There are a couple of places where we put a bio into a cell briefly
- * before taking it out again.  In these situations we know that no other
- * bio may be in the cell.  This function releases the cell, and also does
- * a sanity check.
- */
-static void __cell_release_singleton(struct dm_bio_prison_cell *cell, struct bio *bio)
-{
-        BUG_ON(cell->holder != bio);
-        BUG_ON(!bio_list_empty(&cell->bios));
-
-        __cell_release(cell, NULL);
-}
-
-void dm_cell_release_singleton(struct dm_bio_prison_cell *cell, struct bio *bio)
-{
-        unsigned long flags;
-        struct dm_bio_prison *prison = cell->prison;
-
-        spin_lock_irqsave(&prison->lock, flags);
-        __cell_release_singleton(cell, bio);
-        spin_unlock_irqrestore(&prison->lock, flags);
-}
-EXPORT_SYMBOL_GPL(dm_cell_release_singleton);
-
-/*
  * Sometimes we don't want the holder, just the additional bios.
  */
 static void __cell_release_no_holder(struct dm_bio_prison_cell *cell, struct bio_list *inmates)
diff --git a/drivers/md/dm-bio-prison.h b/drivers/md/dm-bio-prison.h
index 4e0ac376700a..53d1a7a84e2f 100644
--- a/drivers/md/dm-bio-prison.h
+++ b/drivers/md/dm-bio-prison.h
@@ -44,7 +44,6 @@ int dm_bio_detain(struct dm_bio_prison *prison, struct dm_cell_key *key,
                   struct bio *inmate, struct dm_bio_prison_cell **ref);
 
 void dm_cell_release(struct dm_bio_prison_cell *cell, struct bio_list *bios);
-void dm_cell_release_singleton(struct dm_bio_prison_cell *cell, struct bio *bio); // FIXME: bio arg not needed
 void dm_cell_release_no_holder(struct dm_bio_prison_cell *cell, struct bio_list *inmates);
 void dm_cell_error(struct dm_bio_prison_cell *cell);
 
diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c
index bbf459bca61d..f7369f9d8595 100644
--- a/drivers/md/dm-crypt.c
+++ b/drivers/md/dm-crypt.c
@@ -1689,8 +1689,7 @@ bad:
         return ret;
 }
 
-static int crypt_map(struct dm_target *ti, struct bio *bio,
-                     union map_info *map_context)
+static int crypt_map(struct dm_target *ti, struct bio *bio)
 {
         struct dm_crypt_io *io;
         struct crypt_config *cc = ti->private;
@@ -1846,7 +1845,7 @@ static int crypt_iterate_devices(struct dm_target *ti,
 
 static struct target_type crypt_target = {
         .name   = "crypt",
-        .version = {1, 11, 0},
+        .version = {1, 12, 0},
         .module = THIS_MODULE,
         .ctr    = crypt_ctr,
         .dtr    = crypt_dtr,
diff --git a/drivers/md/dm-delay.c b/drivers/md/dm-delay.c
index f53846f9ab50..cc1bd048acb2 100644
--- a/drivers/md/dm-delay.c
+++ b/drivers/md/dm-delay.c
@@ -274,8 +274,7 @@ static void delay_resume(struct dm_target *ti)
         atomic_set(&dc->may_delay, 1);
 }
 
-static int delay_map(struct dm_target *ti, struct bio *bio,
-                     union map_info *map_context)
+static int delay_map(struct dm_target *ti, struct bio *bio)
 {
         struct delay_c *dc = ti->private;
 
@@ -338,7 +337,7 @@ out:
 
 static struct target_type delay_target = {
         .name        = "delay",
-        .version     = {1, 1, 0},
+        .version     = {1, 2, 0},
         .module      = THIS_MODULE,
         .ctr         = delay_ctr,
         .dtr         = delay_dtr,
diff --git a/drivers/md/dm-flakey.c b/drivers/md/dm-flakey.c
index cc15543a6ad7..9721f2ffb1a2 100644
--- a/drivers/md/dm-flakey.c
+++ b/drivers/md/dm-flakey.c
@@ -39,6 +39,10 @@ enum feature_flag_bits {
         DROP_WRITES
 };
 
+struct per_bio_data {
+        bool bio_submitted;
+};
+
 static int parse_features(struct dm_arg_set *as, struct flakey_c *fc,
                           struct dm_target *ti)
 {
@@ -214,6 +218,7 @@ static int flakey_ctr(struct dm_target *ti, unsigned int argc, char **argv)
 
         ti->num_flush_requests = 1;
         ti->num_discard_requests = 1;
+        ti->per_bio_data_size = sizeof(struct per_bio_data);
         ti->private = fc;
         return 0;
 
@@ -265,11 +270,12 @@ static void corrupt_bio_data(struct bio *bio, struct flakey_c *fc)
         }
 }
 
-static int flakey_map(struct dm_target *ti, struct bio *bio,
-                      union map_info *map_context)
+static int flakey_map(struct dm_target *ti, struct bio *bio)
 {
         struct flakey_c *fc = ti->private;
         unsigned elapsed;
+        struct per_bio_data *pb = dm_per_bio_data(bio, sizeof(struct per_bio_data));
+        pb->bio_submitted = false;
 
         /* Are we alive ? */
         elapsed = (jiffies - fc->start_time) / HZ;
@@ -277,7 +283,7 @@ static int flakey_map(struct dm_target *ti, struct bio *bio,