From: Dave Jiang Subject: [PATCH v4 2/3] dax: change bdev_dax_supported() to support boolean returns Date: Thu, 15 Feb 2018 10:42:38 -0700 Message-ID: <151871655831.27617.969797567050409931.stgit@djiang5-desk3.ch.intel.com> References: <151871644696.27617.4390718895806529377.stgit@djiang5-desk3.ch.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: linux-nvdimm-hn68Rpc1hR1g9hUCZPvPmw@public.gmane.org, david-FqsqvQoI3Ljby3iVrkZq2A@public.gmane.org, linux-xfs-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-ext4-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: darrick.wong-QHcLZuEGTsvQT0dZR+AlfA@public.gmane.org Return-path: In-Reply-To: <151871644696.27617.4390718895806529377.stgit-Cxk7aZI4ujnJARH06PadV2t3HXsI98Cx0E9HWUfgJXw@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: linux-nvdimm-bounces-hn68Rpc1hR1g9hUCZPvPmw@public.gmane.org Sender: "Linux-nvdimm" List-Id: linux-ext4.vger.kernel.org The function return values are confusing with the way the function is named. We expect a true or false return value but it actually returns 0/-errno. This makes the code very confusing. Changing the return values to return a bool where if DAX is supported then return true and no DAX support returns false. Signed-off-by: Dave Jiang --- drivers/dax/super.c | 20 ++++++++++---------- fs/ext2/super.c | 3 +-- fs/ext4/super.c | 3 +-- fs/xfs/xfs_ioctl.c | 4 ++-- fs/xfs/xfs_super.c | 10 +++++----- include/linux/dax.h | 12 ++++++------ 6 files changed, 25 insertions(+), 27 deletions(-) diff --git a/drivers/dax/super.c b/drivers/dax/super.c index 8a3a168a267f..42e58eea305e 100644 --- a/drivers/dax/super.c +++ b/drivers/dax/super.c @@ -81,9 +81,9 @@ EXPORT_SYMBOL_GPL(fs_dax_get_by_bdev); * This is a library function for filesystems to check if the block device * can be mounted with dax option. * - * Return: negative errno if unsupported, 0 if supported. + * Return: true if supported, false if unsupported */ -int bdev_dax_supported(struct super_block *sb, struct block_device *bdev, +bool bdev_dax_supported(struct super_block *sb, struct block_device *bdev, int blocksize) { struct dax_device *dax_dev; @@ -96,21 +96,21 @@ int bdev_dax_supported(struct super_block *sb, struct block_device *bdev, if (blocksize != PAGE_SIZE) { pr_debug("VFS (%s): error: unsupported blocksize for dax\n", sb->s_id); - return -EINVAL; + return false; } err = bdev_dax_pgoff(bdev, 0, PAGE_SIZE, &pgoff); if (err) { - pr_debug("VFS (%s): error: unaligned partition for dax\n", - sb->s_id); - return err; + pr_debug("VFS (%s): error: unaligned partition for dax: %d\n", + sb->s_id, err); + return false; } dax_dev = dax_get_by_host(bdev->bd_disk->disk_name); if (!dax_dev) { pr_debug("VFS (%s): error: device does not support dax\n", sb->s_id); - return -EOPNOTSUPP; + return false; } id = dax_read_lock(); @@ -122,7 +122,7 @@ int bdev_dax_supported(struct super_block *sb, struct block_device *bdev, if (len < 1) { pr_debug("VFS (%s): error: dax access failed (%ld)\n", sb->s_id, len); - return len < 0 ? len : -EIO; + return false; } if ((IS_ENABLED(CONFIG_FS_DAX_LIMITED) && pfn_t_special(pfn)) @@ -131,10 +131,10 @@ int bdev_dax_supported(struct super_block *sb, struct block_device *bdev, else { pr_debug("VFS (%s): error: dax support not enabled\n", sb->s_id); - return -EOPNOTSUPP; + return false; } - return 0; + return true; } EXPORT_SYMBOL_GPL(bdev_dax_supported); #endif diff --git a/fs/ext2/super.c b/fs/ext2/super.c index 28ca694e9e92..6901ba1d65d1 100644 --- a/fs/ext2/super.c +++ b/fs/ext2/super.c @@ -961,8 +961,7 @@ static int ext2_fill_super(struct super_block *sb, void *data, int silent) blocksize = BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size); if (sbi->s_mount_opt & EXT2_MOUNT_DAX) { - err = sb_dax_supported(sb, blocksize); - if (err) { + if(!sb_dax_supported(sb, blocksize)) { ext2_msg(sb, KERN_ERR, "DAX unsupported by block device. Turning off DAX."); sbi->s_mount_opt &= ~EXT2_MOUNT_DAX; diff --git a/fs/ext4/super.c b/fs/ext4/super.c index a09f832aad35..8b4ee5f5c17b 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -3714,8 +3714,7 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent) " that may contain inline data"); sbi->s_mount_opt &= ~EXT4_MOUNT_DAX; } - err = sb_dax_supported(sb, blocksize); - if (err) { + if (!sb_dax_supported(sb, blocksize)) { ext4_msg(sb, KERN_ERR, "DAX unsupported by block device. Turning off DAX."); sbi->s_mount_opt &= ~EXT4_MOUNT_DAX; diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c index 277355f5c084..a6a0efc35c76 100644 --- a/fs/xfs/xfs_ioctl.c +++ b/fs/xfs/xfs_ioctl.c @@ -1103,8 +1103,8 @@ xfs_ioctl_setattr_dax_invalidate( if (fa->fsx_xflags & FS_XFLAG_DAX) { if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode))) return -EINVAL; - if (bdev_dax_supported(sb, xfs_find_bdev_for_inode(VFS_I(ip)), - sb->s_blocksize) < 0) + if (!bdev_dax_supported(sb, xfs_find_bdev_for_inode(VFS_I(ip)), + sb->s_blocksize)) return -EINVAL; } diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c index f6c74ef9722c..80658e0f01c2 100644 --- a/fs/xfs/xfs_super.c +++ b/fs/xfs/xfs_super.c @@ -1657,18 +1657,18 @@ xfs_fs_fill_super( sb->s_flags |= SB_I_VERSION; if (mp->m_flags & XFS_MOUNT_DAX) { - int error2 = 0; + bool rtdev_is_dax, datadev_is_dax; xfs_warn(mp, "DAX enabled. Warning: EXPERIMENTAL, use at your own risk"); - error = bdev_dax_supported(sb, mp->m_ddev_targp->bt_bdev, - sb->s_blocksize); + datadev_is_dax = bdev_dax_supported(sb, + mp->m_ddev_targp->bt_bdev, sb->s_blocksize); if (mp->m_rtdev_targp) - error2 = bdev_dax_supported(sb, + rtdev_is_dax = bdev_dax_supported(sb, mp->m_rtdev_targp->bt_bdev, sb->s_blocksize); - if (error && error2) { + if (!rtdev_is_dax && !datadev_is_dax) { xfs_alert(mp, "DAX unsupported by block device. Turning off DAX."); mp->m_flags &= ~XFS_MOUNT_DAX; diff --git a/include/linux/dax.h b/include/linux/dax.h index e640c8a19ec0..f733edd3a9dc 100644 --- a/include/linux/dax.h +++ b/include/linux/dax.h @@ -40,9 +40,9 @@ static inline void put_dax(struct dax_device *dax_dev) int bdev_dax_pgoff(struct block_device *, sector_t, size_t, pgoff_t *pgoff); #if IS_ENABLED(CONFIG_FS_DAX) -int bdev_dax_supported(struct super_block *sb, struct block_device *bdev, +bool bdev_dax_supported(struct super_block *sb, struct block_device *bdev, int blocksize); -static inline int sb_dax_supported(struct super_block *sb, int blocksize) +static inline bool sb_dax_supported(struct super_block *sb, int blocksize) { return bdev_dax_supported(sb, sb->s_bdev, blocksize); } @@ -59,16 +59,16 @@ static inline void fs_put_dax(struct dax_device *dax_dev) struct dax_device *fs_dax_get_by_bdev(struct block_device *bdev); #else -static inline int bdev_dax_supported(struct super_block *sb, +static inline bool bdev_dax_supported(struct super_block *sb, struct block_device *bdev, int blocksize) { - return -EOPNOTSUPP; + return false; } -static inline int sb_dax_supported(struct super_block *sb, int blocksize) +static inline bool sb_dax_supported(struct super_block *sb, int blocksize) { - return -EOPNOTSUPP; + return false; } static inline struct dax_device *fs_dax_get_by_host(const char *host)