Merge branch 'for-4.17/dax' into libnvdimm-for-next

5 files changed, 69 insertions, 50 deletions

diff --git a/drivers/md/Kconfig b/drivers/md/Kconfig
index 2c8ac3688815..edff083f7c4e 100644
--- a/drivers/md/Kconfig
+++ b/drivers/md/Kconfig
@@ -201,7 +201,7 @@ config BLK_DEV_DM_BUILTIN
 config BLK_DEV_DM
         tristate "Device mapper support"
         select BLK_DEV_DM_BUILTIN
-        select DAX
+        depends on DAX || DAX=n
         ---help---
           Device-mapper is a low level volume manager.  It works by allowing
           people to specify mappings for ranges of logical sectors.  Various
diff --git a/drivers/md/dm-linear.c b/drivers/md/dm-linear.c
index d5f8eff7c11d..89443e0ededa 100644
--- a/drivers/md/dm-linear.c
+++ b/drivers/md/dm-linear.c
@@ -154,6 +154,7 @@ static int linear_iterate_devices(struct dm_target *ti,
         return fn(ti, lc->dev, lc->start, ti->len, data);
 }
 
+#if IS_ENABLED(CONFIG_DAX_DRIVER)
 static long linear_dax_direct_access(struct dm_target *ti, pgoff_t pgoff,
                 long nr_pages, void **kaddr, pfn_t *pfn)
 {
@@ -184,6 +185,11 @@ static size_t linear_dax_copy_from_iter(struct dm_target *ti, pgoff_t pgoff,
         return dax_copy_from_iter(dax_dev, pgoff, addr, bytes, i);
 }
 
+#else
+#define linear_dax_direct_access NULL
+#define linear_dax_copy_from_iter NULL
+#endif
+
 static struct target_type linear_target = {
         .name   = "linear",
         .version = {1, 4, 0},
diff --git a/drivers/md/dm-log-writes.c b/drivers/md/dm-log-writes.c
index 3362d866793b..7fcb4216973f 100644
--- a/drivers/md/dm-log-writes.c
+++ b/drivers/md/dm-log-writes.c
@@ -610,51 +610,6 @@ static int log_mark(struct log_writes_c *lc, char *data)
         return 0;
 }
 
-static int log_dax(struct log_writes_c *lc, sector_t sector, size_t bytes,
-                   struct iov_iter *i)
-{
-        struct pending_block *block;
-
-        if (!bytes)
-                return 0;
-
-        block = kzalloc(sizeof(struct pending_block), GFP_KERNEL);
-        if (!block) {
-                DMERR("Error allocating dax pending block");
-                return -ENOMEM;
-        }
-
-        block->data = kzalloc(bytes, GFP_KERNEL);
-        if (!block->data) {
-                DMERR("Error allocating dax data space");
-                kfree(block);
-                return -ENOMEM;
-        }
-
-        /* write data provided via the iterator */
-        if (!copy_from_iter(block->data, bytes, i)) {
-                DMERR("Error copying dax data");
-                kfree(block->data);
-                kfree(block);
-                return -EIO;
-        }
-
-        /* rewind the iterator so that the block driver can use it */
-        iov_iter_revert(i, bytes);
-
-        block->datalen = bytes;
-        block->sector = bio_to_dev_sectors(lc, sector);
-        block->nr_sectors = ALIGN(bytes, lc->sectorsize) >> lc->sectorshift;
-
-        atomic_inc(&lc->pending_blocks);
-        spin_lock_irq(&lc->blocks_lock);
-        list_add_tail(&block->list, &lc->unflushed_blocks);
-        spin_unlock_irq(&lc->blocks_lock);
-        wake_up_process(lc->log_kthread);
-
-        return 0;
-}
-
 static void log_writes_dtr(struct dm_target *ti)
 {
         struct log_writes_c *lc = ti->private;
@@ -920,6 +875,52 @@ static void log_writes_io_hints(struct dm_target *ti, struct queue_limits *limit
         limits->io_min = limits->physical_block_size;
 }
 
+#if IS_ENABLED(CONFIG_DAX_DRIVER)
+static int log_dax(struct log_writes_c *lc, sector_t sector, size_t bytes,
+                   struct iov_iter *i)
+{
+        struct pending_block *block;
+
+        if (!bytes)
+                return 0;
+
+        block = kzalloc(sizeof(struct pending_block), GFP_KERNEL);
+        if (!block) {
+                DMERR("Error allocating dax pending block");
+                return -ENOMEM;
+        }
+
+        block->data = kzalloc(bytes, GFP_KERNEL);
+        if (!block->data) {
+                DMERR("Error allocating dax data space");
+                kfree(block);
+                return -ENOMEM;
+        }
+
+        /* write data provided via the iterator */
+        if (!copy_from_iter(block->data, bytes, i)) {
+                DMERR("Error copying dax data");
+                kfree(block->data);
+                kfree(block);
+                return -EIO;
+        }
+
+        /* rewind the iterator so that the block driver can use it */
+        iov_iter_revert(i, bytes);
+
+        block->datalen = bytes;
+        block->sector = bio_to_dev_sectors(lc, sector);
+        block->nr_sectors = ALIGN(bytes, lc->sectorsize) >> lc->sectorshift;
+
+        atomic_inc(&lc->pending_blocks);
+        spin_lock_irq(&lc->blocks_lock);
+        list_add_tail(&block->list, &lc->unflushed_blocks);
+        spin_unlock_irq(&lc->blocks_lock);
+        wake_up_process(lc->log_kthread);
+
+        return 0;
+}
+
 static long log_writes_dax_direct_access(struct dm_target *ti, pgoff_t pgoff,
                                          long nr_pages, void **kaddr, pfn_t *pfn)
 {
@@ -956,6 +957,10 @@ static size_t log_writes_dax_copy_from_iter(struct dm_target *ti,
 dax_copy:
         return dax_copy_from_iter(lc->dev->dax_dev, pgoff, addr, bytes, i);
 }
+#else
+#define log_writes_dax_direct_access NULL
+#define log_writes_dax_copy_from_iter NULL
+#endif
 
 static struct target_type log_writes_target = {
         .name   = "log-writes",
diff --git a/drivers/md/dm-stripe.c b/drivers/md/dm-stripe.c
index b5e892149c54..ac2e8ee9d586 100644
--- a/drivers/md/dm-stripe.c
+++ b/drivers/md/dm-stripe.c
@@ -311,6 +311,7 @@ static int stripe_map(struct dm_target *ti, struct bio *bio)
         return DM_MAPIO_REMAPPED;
 }
 
+#if IS_ENABLED(CONFIG_DAX_DRIVER)
 static long stripe_dax_direct_access(struct dm_target *ti, pgoff_t pgoff,
                 long nr_pages, void **kaddr, pfn_t *pfn)
 {
@@ -351,6 +352,11 @@ static size_t stripe_dax_copy_from_iter(struct dm_target *ti, pgoff_t pgoff,
         return dax_copy_from_iter(dax_dev, pgoff, addr, bytes, i);
 }
 
+#else
+#define stripe_dax_direct_access NULL
+#define stripe_dax_copy_from_iter NULL
+#endif
+
 /*
  * Stripe status:
  *
diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index 45328d8b2859..bac79f40f3cb 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -1805,7 +1805,7 @@ static void cleanup_mapped_device(struct mapped_device *md)
 static struct mapped_device *alloc_dev(int minor)
 {
         int r, numa_node_id = dm_get_numa_node();
-        struct dax_device *dax_dev;
+        struct dax_device *dax_dev = NULL;
         struct mapped_device *md;
         void *old_md;
 
@@ -1871,9 +1871,11 @@ static struct mapped_device *alloc_dev(int minor)
         md->disk->private_data = md;
         sprintf(md->disk->disk_name, "dm-%d", minor);
 
-        dax_dev = alloc_dax(md, md->disk->disk_name, &dm_dax_ops);
-        if (!dax_dev)
-                goto bad;
+        if (IS_ENABLED(CONFIG_DAX_DRIVER)) {
+                dax_dev = alloc_dax(md, md->disk->disk_name, &dm_dax_ops);
+                if (!dax_dev)
+                        goto bad;
+        }
         md->dax_dev = dax_dev;
 
         add_disk_no_queue_reg(md->disk);