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
  ...

7 files changed, 77 insertions, 70 deletions

diff --git a/drivers/md/persistent-data/dm-block-manager.c b/drivers/md/persistent-data/dm-block-manager.c
index a3ae09124a67..28c3ed072a79 100644
--- a/drivers/md/persistent-data/dm-block-manager.c
+++ b/drivers/md/persistent-data/dm-block-manager.c
@@ -428,15 +428,17 @@ static int dm_bm_validate_buffer(struct dm_block_manager *bm,
                 if (!v)
                         return 0;
                 r = v->check(v, (struct dm_block *) buf, dm_bufio_get_block_size(bm->bufio));
-                if (unlikely(r))
+                if (unlikely(r)) {
+                        DMERR_LIMIT("%s validator check failed for block %llu", v->name,
+                                    (unsigned long long) dm_bufio_get_block_number(buf));
                         return r;
+                }
                 aux->validator = v;
         } else {
                 if (unlikely(aux->validator != v)) {
-                        DMERR("validator mismatch (old=%s vs new=%s) for block %llu",
-                                aux->validator->name, v ? v->name : "NULL",
-                                (unsigned long long)
-                                        dm_bufio_get_block_number(buf));
+                        DMERR_LIMIT("validator mismatch (old=%s vs new=%s) for block %llu",
+                                    aux->validator->name, v ? v->name : "NULL",
+                                    (unsigned long long) dm_bufio_get_block_number(buf));
                         return -EINVAL;
                 }
         }
diff --git a/drivers/md/persistent-data/dm-btree-internal.h b/drivers/md/persistent-data/dm-btree-internal.h
index 5709bfeab1e8..accbb05f17b6 100644
--- a/drivers/md/persistent-data/dm-btree-internal.h
+++ b/drivers/md/persistent-data/dm-btree-internal.h
@@ -36,13 +36,13 @@ struct node_header {
         __le32 padding;
 } __packed;
 
-struct node {
+struct btree_node {
         struct node_header header;
         __le64 keys[0];
 } __packed;
 
 
-void inc_children(struct dm_transaction_manager *tm, struct node *n,
+void inc_children(struct dm_transaction_manager *tm, struct btree_node *n,
                   struct dm_btree_value_type *vt);
 
 int new_block(struct dm_btree_info *info, struct dm_block **result);
@@ -64,7 +64,7 @@ struct ro_spine {
 void init_ro_spine(struct ro_spine *s, struct dm_btree_info *info);
 int exit_ro_spine(struct ro_spine *s);
 int ro_step(struct ro_spine *s, dm_block_t new_child);
-struct node *ro_node(struct ro_spine *s);
+struct btree_node *ro_node(struct ro_spine *s);
 
 struct shadow_spine {
         struct dm_btree_info *info;
@@ -98,17 +98,17 @@ int shadow_root(struct shadow_spine *s);
 /*
  * Some inlines.
  */
-static inline __le64 *key_ptr(struct node *n, uint32_t index)
+static inline __le64 *key_ptr(struct btree_node *n, uint32_t index)
 {
         return n->keys + index;
 }
 
-static inline void *value_base(struct node *n)
+static inline void *value_base(struct btree_node *n)
 {
         return &n->keys[le32_to_cpu(n->header.max_entries)];
 }
 
-static inline void *value_ptr(struct node *n, uint32_t index)
+static inline void *value_ptr(struct btree_node *n, uint32_t index)
 {
         uint32_t value_size = le32_to_cpu(n->header.value_size);
         return value_base(n) + (value_size * index);
@@ -117,7 +117,7 @@ static inline void *value_ptr(struct node *n, uint32_t index)
 /*
  * Assumes the values are suitably-aligned and converts to core format.
  */
-static inline uint64_t value64(struct node *n, uint32_t index)
+static inline uint64_t value64(struct btree_node *n, uint32_t index)
 {
         __le64 *values_le = value_base(n);
 
@@ -127,7 +127,7 @@ static inline uint64_t value64(struct node *n, uint32_t index)
 /*
  * Searching for a key within a single node.
  */
-int lower_bound(struct node *n, uint64_t key);
+int lower_bound(struct btree_node *n, uint64_t key);
 
 extern struct dm_block_validator btree_node_validator;
 
diff --git a/drivers/md/persistent-data/dm-btree-remove.c b/drivers/md/persistent-data/dm-btree-remove.c
index aa71e2359a07..c4f28133ef82 100644
--- a/drivers/md/persistent-data/dm-btree-remove.c
+++ b/drivers/md/persistent-data/dm-btree-remove.c
@@ -53,7 +53,7 @@
 /*
  * Some little utilities for moving node data around.
  */
-static void node_shift(struct node *n, int shift)
+static void node_shift(struct btree_node *n, int shift)
 {
         uint32_t nr_entries = le32_to_cpu(n->header.nr_entries);
         uint32_t value_size = le32_to_cpu(n->header.value_size);
@@ -79,7 +79,7 @@ static void node_shift(struct node *n, int shift)
         }
 }
 
-static void node_copy(struct node *left, struct node *right, int shift)
+static void node_copy(struct btree_node *left, struct btree_node *right, int shift)
 {
         uint32_t nr_left = le32_to_cpu(left->header.nr_entries);
         uint32_t value_size = le32_to_cpu(left->header.value_size);
@@ -108,7 +108,7 @@ static void node_copy(struct node *left, struct node *right, int shift)
 /*
  * Delete a specific entry from a leaf node.
  */
-static void delete_at(struct node *n, unsigned index)
+static void delete_at(struct btree_node *n, unsigned index)
 {
         unsigned nr_entries = le32_to_cpu(n->header.nr_entries);
         unsigned nr_to_copy = nr_entries - (index + 1);
@@ -128,7 +128,7 @@ static void delete_at(struct node *n, unsigned index)
         n->header.nr_entries = cpu_to_le32(nr_entries - 1);
 }
 
-static unsigned merge_threshold(struct node *n)
+static unsigned merge_threshold(struct btree_node *n)
 {
         return le32_to_cpu(n->header.max_entries) / 3;
 }
@@ -136,7 +136,7 @@ static unsigned merge_threshold(struct node *n)
 struct child {
         unsigned index;
         struct dm_block *block;
-        struct node *n;
+        struct btree_node *n;
 };
 
 static struct dm_btree_value_type le64_type = {
@@ -147,7 +147,7 @@ static struct dm_btree_value_type le64_type = {
         .equal = NULL
 };
 
-static int init_child(struct dm_btree_info *info, struct node *parent,
+static int init_child(struct dm_btree_info *info,