From a8078b1fc616da6112eb95f0063cd34531d4ccf0 Mon Sep 17 00:00:00 2001 From: Toshi Kani Date: Tue, 10 May 2016 10:23:57 -0600 Subject: [PATCH] block: Update blkdev_dax_capable() for consistency blkdev_dax_capable() is similar to bdev_dax_supported(), but needs to remain as a separate interface for checking dax capability of a raw block device. Rename and relocate blkdev_dax_capable() to keep them maintained consistently, and call bdev_direct_access() for the dax capability check. There is no change in the behavior. Link: https://lkml.org/lkml/2016/5/9/950 Signed-off-by: Toshi Kani Reviewed-by: Jan Kara Cc: Alexander Viro Cc: Jens Axboe Cc: Andreas Dilger Cc: Jan Kara Cc: Dave Chinner Cc: Dan Williams Cc: Ross Zwisler Cc: Christoph Hellwig Cc: Boaz Harrosh Signed-off-by: Vishal Verma --- block/ioctl.c | 30 ------------------------------ fs/block_dev.c | 39 +++++++++++++++++++++++++++++++++++++-- include/linux/blkdev.h | 1 + include/linux/fs.h | 8 -------- 4 files changed, 38 insertions(+), 40 deletions(-) diff --git a/block/ioctl.c b/block/ioctl.c index 4ff1f92f89ca..7eeda072dc70 100644 --- a/block/ioctl.c +++ b/block/ioctl.c @@ -4,7 +4,6 @@ #include #include #include -#include #include #include #include @@ -407,35 +406,6 @@ static inline int is_unrecognized_ioctl(int ret) ret == -ENOIOCTLCMD; } -#ifdef CONFIG_FS_DAX -bool blkdev_dax_capable(struct block_device *bdev) -{ - struct gendisk *disk = bdev->bd_disk; - - if (!disk->fops->direct_access) - return false; - - /* - * If the partition is not aligned on a page boundary, we can't - * do dax I/O to it. - */ - if ((bdev->bd_part->start_sect % (PAGE_SIZE / 512)) - || (bdev->bd_part->nr_sects % (PAGE_SIZE / 512))) - return false; - - /* - * If the device has known bad blocks, force all I/O through the - * driver / page cache. - * - * TODO: support finer grained dax error handling - */ - if (disk->bb && disk->bb->count) - return false; - - return true; -} -#endif - static int blkdev_flushbuf(struct block_device *bdev, fmode_t mode, unsigned cmd, unsigned long arg) { diff --git a/fs/block_dev.c b/fs/block_dev.c index 518cde62c01c..8477d4501b1e 100644 --- a/fs/block_dev.c +++ b/fs/block_dev.c @@ -29,6 +29,7 @@ #include #include #include +#include #include #include "internal.h" @@ -554,6 +555,40 @@ int bdev_dax_supported(struct super_block *sb, int blocksize) } EXPORT_SYMBOL_GPL(bdev_dax_supported); +/** + * bdev_dax_capable() - Return if the raw device is capable for dax + * @bdev: The device for raw block device access + */ +bool bdev_dax_capable(struct block_device *bdev) +{ + struct gendisk *disk = bdev->bd_disk; + struct blk_dax_ctl dax = { + .size = PAGE_SIZE, + }; + + if (!IS_ENABLED(CONFIG_FS_DAX)) + return false; + + dax.sector = 0; + if (bdev_direct_access(bdev, &dax) < 0) + return false; + + dax.sector = bdev->bd_part->nr_sects - (PAGE_SIZE / 512); + if (bdev_direct_access(bdev, &dax) < 0) + return false; + + /* + * If the device has known bad blocks, force all I/O through the + * driver / page cache. + * + * TODO: support finer grained dax error handling + */ + if (disk->bb && disk->bb->count) + return false; + + return true; +} + /* * pseudo-fs */ @@ -1295,7 +1330,7 @@ static int __blkdev_get(struct block_device *bdev, fmode_t mode, int for_part) if (!ret) { bd_set_size(bdev,(loff_t)get_capacity(disk)<<9); - if (!blkdev_dax_capable(bdev)) + if (!bdev_dax_capable(bdev)) bdev->bd_inode->i_flags &= ~S_DAX; } @@ -1332,7 +1367,7 @@ static int __blkdev_get(struct block_device *bdev, fmode_t mode, int for_part) goto out_clear; } bd_set_size(bdev, (loff_t)bdev->bd_part->nr_sects << 9); - if (!blkdev_dax_capable(bdev)) + if (!bdev_dax_capable(bdev)) bdev->bd_inode->i_flags &= ~S_DAX; } } else { diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 71231a55debd..27cbefe8c985 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -1689,6 +1689,7 @@ extern int bdev_write_page(struct block_device *, sector_t, struct page *, struct writeback_control *); extern long bdev_direct_access(struct block_device *, struct blk_dax_ctl *); extern int bdev_dax_supported(struct super_block *, int); +extern bool bdev_dax_capable(struct block_device *); #else /* CONFIG_BLOCK */ struct block_device; diff --git a/include/linux/fs.h b/include/linux/fs.h index 9f2813090d1b..17f934fcf564 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -2319,14 +2319,6 @@ extern struct super_block *freeze_bdev(struct block_device *); extern void emergency_thaw_all(void); extern int thaw_bdev(struct block_device *bdev, struct super_block *sb); extern int fsync_bdev(struct block_device *); -#ifdef CONFIG_FS_DAX -extern bool blkdev_dax_capable(struct block_device *bdev); -#else -static inline bool blkdev_dax_capable(struct block_device *bdev) -{ - return false; -} -#endif extern struct super_block *blockdev_superblock;