Merge branch 'for-4.15/dax' into libnvdimm-for-next

5 files changed, 26 insertions, 107 deletions

diff --git a/drivers/block/Kconfig b/drivers/block/Kconfig
index 4a438b8abe27..da8bf0268ade 100644
--- a/drivers/block/Kconfig
+++ b/drivers/block/Kconfig
@@ -17,7 +17,7 @@ if BLK_DEV
 
 config BLK_DEV_NULL_BLK
 	tristate "Null test block driver"
-	depends on CONFIGFS_FS
+	select CONFIGFS_FS
 
 config BLK_DEV_FD
 	tristate "Normal floppy disk support"
@@ -297,7 +297,6 @@ config BLK_DEV_SX8
 
 config BLK_DEV_RAM
 	tristate "RAM block device support"
-	select DAX if BLK_DEV_RAM_DAX
 	---help---
 	  Saying Y here will allow you to use a portion of your RAM memory as
 	  a block device, so that you can make file systems on it, read and
@@ -333,17 +332,6 @@ config BLK_DEV_RAM_SIZE
 	  The default value is 4096 kilobytes. Only change this if you know
 	  what you are doing.
 
-config BLK_DEV_RAM_DAX
-	bool "Support Direct Access (DAX) to RAM block devices"
-	depends on BLK_DEV_RAM && FS_DAX
-	default n
-	help
-	  Support filesystems using DAX to access RAM block devices.  This
-	  avoids double-buffering data in the page cache before copying it
-	  to the block device.  Answering Y will slightly enlarge the kernel,
-	  and will prevent RAM block device backing store memory from being
-	  allocated from highmem (only a problem for highmem systems).
-
 config CDROM_PKTCDVD
 	tristate "Packet writing on CD/DVD media (DEPRECATED)"
 	depends on !UML
diff --git a/drivers/block/brd.c b/drivers/block/brd.c
index bbd0d186cfc0..b2391bbd7e5a 100644
--- a/drivers/block/brd.c
+++ b/drivers/block/brd.c
@@ -20,11 +20,6 @@
 #include <linux/radix-tree.h>
 #include <linux/fs.h>
 #include <linux/slab.h>
-#ifdef CONFIG_BLK_DEV_RAM_DAX
-#include <linux/pfn_t.h>
-#include <linux/dax.h>
-#include <linux/uio.h>
-#endif
 
 #include <linux/uaccess.h>
 
@@ -44,9 +39,6 @@ struct brd_device {
 
 	struct request_queue	*brd_queue;
 	struct gendisk		*brd_disk;
-#ifdef CONFIG_BLK_DEV_RAM_DAX
-	struct dax_device	*dax_dev;
-#endif
 	struct list_head	brd_list;
 
 	/*
@@ -112,9 +104,6 @@ static struct page *brd_insert_page(struct brd_device *brd, sector_t sector)
 	 * restriction might be able to be lifted.
 	 */
 	gfp_flags = GFP_NOIO | __GFP_ZERO;
-#ifndef CONFIG_BLK_DEV_RAM_DAX
-	gfp_flags |= __GFP_HIGHMEM;
-#endif
 	page = alloc_page(gfp_flags);
 	if (!page)
 		return NULL;
@@ -334,43 +323,6 @@ static int brd_rw_page(struct block_device *bdev, sector_t sector,
 	return err;
 }
 
-#ifdef CONFIG_BLK_DEV_RAM_DAX
-static long __brd_direct_access(struct brd_device *brd, pgoff_t pgoff,
-		long nr_pages, void **kaddr, pfn_t *pfn)
-{
-	struct page *page;
-
-	if (!brd)
-		return -ENODEV;
-	page = brd_insert_page(brd, PFN_PHYS(pgoff) / 512);
-	if (!page)
-		return -ENOSPC;
-	*kaddr = page_address(page);
-	*pfn = page_to_pfn_t(page);
-
-	return 1;
-}
-
-static long brd_dax_direct_access(struct dax_device *dax_dev,
-		pgoff_t pgoff, long nr_pages, void **kaddr, pfn_t *pfn)
-{
-	struct brd_device *brd = dax_get_private(dax_dev);
-
-	return __brd_direct_access(brd, pgoff, nr_pages, kaddr, pfn);
-}
-
-static size_t brd_dax_copy_from_iter(struct dax_device *dax_dev, pgoff_t pgoff,
-		void *addr, size_t bytes, struct iov_iter *i)
-{
-	return copy_from_iter(addr, bytes, i);
-}
-
-static const struct dax_operations brd_dax_ops = {
-	.direct_access = brd_dax_direct_access,
-	.copy_from_iter = brd_dax_copy_from_iter,
-};
-#endif
-
 static const struct block_device_operations brd_fops = {
 	.owner =		THIS_MODULE,
 	.rw_page =		brd_rw_page,
@@ -450,21 +402,8 @@ static struct brd_device *brd_alloc(int i)
 	sprintf(disk->disk_name, "ram%d", i);
 	set_capacity(disk, rd_size * 2);
 
-#ifdef CONFIG_BLK_DEV_RAM_DAX
-	queue_flag_set_unlocked(QUEUE_FLAG_DAX, brd->brd_queue);
-	brd->dax_dev = alloc_dax(brd, disk->disk_name, &brd_dax_ops);
-	if (!brd->dax_dev)
-		goto out_free_inode;
-#endif
-
-
 	return brd;
 
-#ifdef CONFIG_BLK_DEV_RAM_DAX
-out_free_inode:
-	kill_dax(brd->dax_dev);
-	put_dax(brd->dax_dev);
-#endif
 out_free_queue:
 	blk_cleanup_queue(brd->brd_queue);
 out_free_dev:
@@ -504,10 +443,6 @@ out:
 static void brd_del_one(struct brd_device *brd)
 {
 	list_del(&brd->brd_list);
-#ifdef CONFIG_BLK_DEV_RAM_DAX
-	kill_dax(brd->dax_dev);
-	put_dax(brd->dax_dev);
-#endif
 	del_gendisk(brd->brd_disk);
 	brd_free(brd);
 }
diff --git a/drivers/block/loop.h b/drivers/block/loop.h
index f68c1d50802f..1f3956702993 100644
--- a/drivers/block/loop.h
+++ b/drivers/block/loop.h
@@ -67,10 +67,8 @@ struct loop_device {
 struct loop_cmd {
 	struct kthread_work work;
 	struct request *rq;
-	union {
-		bool use_aio; /* use AIO interface to handle I/O */
-		atomic_t ref; /* only for aio */
-	};
+	bool use_aio; /* use AIO interface to handle I/O */
+	atomic_t ref; /* only for aio */
 	long ret;
 	struct kiocb iocb;
 	struct bio_vec *bvec;
diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c
index 2aa87cbdede0..883dfebd3014 100644
--- a/drivers/block/nbd.c
+++ b/drivers/block/nbd.c
@@ -820,9 +820,13 @@ static blk_status_t nbd_queue_rq(struct blk_mq_hw_ctx *hctx,
 	 * appropriate.
 	 */
 	ret = nbd_handle_cmd(cmd, hctx->queue_num);
+	if (ret < 0)
+		ret = BLK_STS_IOERR;
+	else if (!ret)
+		ret = BLK_STS_OK;
 	complete(&cmd->send_complete);
 
-	return ret < 0 ? BLK_STS_IOERR : BLK_STS_OK;
+	return ret;
 }
 
 static int nbd_add_socket(struct nbd_device *nbd, unsigned long arg,
@@ -1194,6 +1198,12 @@ static int nbd_ioctl(struct block_device *bdev, fmode_t mode,
 	if (!capable(CAP_SYS_ADMIN))
 		return -EPERM;
 
+	/* The block layer will pass back some non-nbd ioctls in case we have
+	 * special handling for them, but we don't so just return an error.
+	 */
+	if (_IOC_TYPE(cmd) != 0xab)
+		return -EINVAL;
+
 	mutex_lock(&nbd->config_lock);
 
 	/* Don't allow ioctl operations on a nbd device that was created with
diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c
index 2981c27d3aae..f149d3e61234 100644
--- a/drivers/block/zram/zram_drv.c
+++ b/drivers/block/zram/zram_drv.c
@@ -766,27 +766,6 @@ static void zram_slot_unlock(struct zram *zram, u32 index)
 	bit_spin_unlock(ZRAM_ACCESS, &zram->table[index].value);
 }
 
-static bool zram_same_page_read(struct zram *zram, u32 index,
-				struct page *page,
-				unsigned int offset, unsigned int len)
-{
-	zram_slot_lock(zram, index);
-	if (unlikely(!zram_get_handle(zram, index) ||
-			zram_test_flag(zram, index, ZRAM_SAME))) {
-		void *mem;
-
-		zram_slot_unlock(zram, index);
-		mem = kmap_atomic(page);
-		zram_fill_page(mem + offset, len,
-					zram_get_element(zram, index));
-		kunmap_atomic(mem);
-		return true;
-	}
-	zram_slot_unlock(zram, index);
-
-	return false;
-}
-
 static void zram_meta_free(struct zram *zram, u64 disksize)
 {
 	size_t num_pages = disksize >> PAGE_SHIFT;
@@ -884,11 +863,20 @@ static int __zram_bvec_read(struct zram *zram, struct page *page, u32 index,
 		zram_slot_unlock(zram, index);
 	}
 
-	if (zram_same_page_read(zram, index, page, 0, PAGE_SIZE))
-		return 0;
-
 	zram_slot_lock(zram, index);
 	handle = zram_get_handle(zram, index);
+	if (!handle || zram_test_flag(zram, index, ZRAM_SAME)) {
+		unsigned long value;
+		void *mem;
+
+		value = handle ? zram_get_element(zram, index) : 0;
+		mem = kmap_atomic(page);
+		zram_fill_page(mem, PAGE_SIZE, value);
+		kunmap_atomic(mem);
+		zram_slot_unlock(zram, index);
+		return 0;
+	}
+
 	size = zram_get_obj_size(zram, index);
 
 	src = zs_map_object(zram->mem_pool, handle, ZS_MM_RO);