Merge branch 'for-linus' of git://git.kernel.dk/linux-block

Pull block layer fixes from Jens Axboe:
 "Two smaller fixes for this cycle:

   - A fixup from Keith so that NVMe compiles without BLK_INTEGRITY,
     basically just moving the code around appropriately.

   - A fixup for shm, fixing an oops in shmem_mapping() for mapping with
     no inode.  From Sasha"

[ The shmem fix doesn't look block-layer-related, but fixes a bug that
  happened due to the backing_dev_info removal..  - Linus ]

* 'for-linus' of git://git.kernel.dk/linux-block:
  mm: shmem: check for mapping owner before dereferencing
  NVMe: Fix for BLK_DEV_INTEGRITY not set

2 files changed, 61 insertions, 41 deletions

diff --git a/drivers/block/nvme-core.c b/drivers/block/nvme-core.c
index b64bccbb78c9..ceb32dd52a6c 100644
--- a/drivers/block/nvme-core.c
+++ b/drivers/block/nvme-core.c
@@ -482,6 +482,7 @@ static int nvme_error_status(u16 status)
         }
 }
 
+#ifdef CONFIG_BLK_DEV_INTEGRITY
 static void nvme_dif_prep(u32 p, u32 v, struct t10_pi_tuple *pi)
 {
         if (be32_to_cpu(pi->ref_tag) == v)
@@ -538,6 +539,58 @@ static void nvme_dif_remap(struct request *req,
         kunmap_atomic(pmap);
 }
 
+static int nvme_noop_verify(struct blk_integrity_iter *iter)
+{
+        return 0;
+}
+
+static int nvme_noop_generate(struct blk_integrity_iter *iter)
+{
+        return 0;
+}
+
+struct blk_integrity nvme_meta_noop = {
+        .name                   = "NVME_META_NOOP",
+        .generate_fn            = nvme_noop_generate,
+        .verify_fn              = nvme_noop_verify,
+};
+
+static void nvme_init_integrity(struct nvme_ns *ns)
+{
+        struct blk_integrity integrity;
+
+        switch (ns->pi_type) {
+        case NVME_NS_DPS_PI_TYPE3:
+                integrity = t10_pi_type3_crc;
+                break;
+        case NVME_NS_DPS_PI_TYPE1:
+        case NVME_NS_DPS_PI_TYPE2:
+                integrity = t10_pi_type1_crc;
+                break;
+        default:
+                integrity = nvme_meta_noop;
+                break;
+        }
+        integrity.tuple_size = ns->ms;
+        blk_integrity_register(ns->disk, &integrity);
+        blk_queue_max_integrity_segments(ns->queue, 1);
+}
+#else /* CONFIG_BLK_DEV_INTEGRITY */
+static void nvme_dif_remap(struct request *req,
+                        void (*dif_swap)(u32 p, u32 v, struct t10_pi_tuple *pi))
+{
+}
+static void nvme_dif_prep(u32 p, u32 v, struct t10_pi_tuple *pi)
+{
+}
+static void nvme_dif_complete(u32 p, u32 v, struct t10_pi_tuple *pi)
+{
+}
+static void nvme_init_integrity(struct nvme_ns *ns)
+{
+}
+#endif
+
 static void req_completion(struct nvme_queue *nvmeq, void *ctx,
                                                 struct nvme_completion *cqe)
 {
@@ -1959,43 +2012,6 @@ static void nvme_config_discard(struct nvme_ns *ns)
         queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, ns->queue);
 }
 
-static int nvme_noop_verify(struct blk_integrity_iter *iter)
-{
-        return 0;
-}
-
-static int nvme_noop_generate(struct blk_integrity_iter *iter)
-{
-        return 0;
-}
-
-struct blk_integrity nvme_meta_noop = {
-        .name                   = "NVME_META_NOOP",
-        .generate_fn            = nvme_noop_generate,
-        .verify_fn              = nvme_noop_verify,
-};
-
-static void nvme_init_integrity(struct nvme_ns *ns)
-{
-        struct blk_integrity integrity;
-
-        switch (ns->pi_type) {
-        case NVME_NS_DPS_PI_TYPE3:
-                integrity = t10_pi_type3_crc;
-                break;
-        case NVME_NS_DPS_PI_TYPE1:
-        case NVME_NS_DPS_PI_TYPE2:
-                integrity = t10_pi_type1_crc;
-                break;
-        default:
-                integrity = nvme_meta_noop;
-                break;
-        }
-        integrity.tuple_size = ns->ms;
-        blk_integrity_register(ns->disk, &integrity);
-        blk_queue_max_integrity_segments(ns->queue, 1);
-}
-
 static int nvme_revalidate_disk(struct gendisk *disk)
 {
         struct nvme_ns *ns = disk->private_data;
@@ -2036,7 +2052,8 @@ static int nvme_revalidate_disk(struct gendisk *disk)
         pi_type = ns->ms == sizeof(struct t10_pi_tuple) ?
                                         id->dps & NVME_NS_DPS_PI_MASK : 0;
 
-        if (disk->integrity && (ns->pi_type != pi_type || ns->ms != old_ms ||
+        if (blk_get_integrity(disk) && (ns->pi_type != pi_type ||
+                                ns->ms != old_ms ||
                                 bs != queue_logical_block_size(disk->queue) ||
                                 (ns->ms && id->flbas & NVME_NS_FLBAS_META_EXT)))
                 blk_integrity_unregister(disk);
@@ -2044,11 +2061,11 @@ static int nvme_revalidate_disk(struct gendisk *disk)
         ns->pi_type = pi_type;
         blk_queue_logical_block_size(ns->queue, bs);
 
-        if (ns->ms && !disk->integrity && (disk->flags & GENHD_FL_UP) &&
+        if (ns->ms && !blk_get_integrity(disk) && (disk->flags & GENHD_FL_UP) &&
                                 !(id->flbas & NVME_NS_FLBAS_META_EXT))
                 nvme_init_integrity(ns);
 
-        if (id->ncap == 0 || (ns->ms && !disk->integrity))
+        if (id->ncap == 0 || (ns->ms && !blk_get_integrity(disk)))
                 set_capacity(disk, 0);
         else
                 set_capacity(disk, le64_to_cpup(&id->nsze) << (ns->lba_shift - 9));
@@ -2652,7 +2669,7 @@ static void nvme_dev_remove(struct nvme_dev *dev)
 
         list_for_each_entry(ns, &dev->namespaces, list) {
                 if (ns->disk->flags & GENHD_FL_UP) {
-                        if (ns->disk->integrity)
+                        if (blk_get_integrity(ns->disk))
                                 blk_integrity_unregister(ns->disk);
                         del_gendisk(ns->disk);
                 }
diff --git a/mm/shmem.c b/mm/shmem.c
index 2f17cb5f00a4..cf2d0ca010bc 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -1455,6 +1455,9 @@ static struct inode *shmem_get_inode(struct super_block *sb, const struct inode
 
 bool shmem_mapping(struct address_space *mapping)
 {
+        if (!mapping->host)
+                return false;
+
         return mapping->host->i_sb->s_op == &shmem_ops;
 }