| Message ID | 20211202084856.1285285-8-ruansy.fnst@fujitsu.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | fsdax: introduce fs query to support reflink | expand |
On Thu, Dec 02, 2021 at 04:48:54PM +0800, Shiyang Ruan wrote:
> Add these helper functions, and export them for filesystem use.
What is the point of adding these wrappers vs just calling the
underlying functions?
在 2021/12/14 23:47, Christoph Hellwig 写道: > On Thu, Dec 02, 2021 at 04:48:54PM +0800, Shiyang Ruan wrote: >> Add these helper functions, and export them for filesystem use. > > What is the point of adding these wrappers vs just calling the > underlying functions? I added them so that they can be called in a friendly way, even if CONFIG_DAX is off. Otherwise, we need #if IS_ENABLED(CONFIG_DAX) to wrap them where they are called. -- Thanks, Ruan.
On Wed, Dec 15, 2021 at 10:21:00AM +0800, Shiyang Ruan wrote: > > > 在 2021/12/14 23:47, Christoph Hellwig 写道: > > On Thu, Dec 02, 2021 at 04:48:54PM +0800, Shiyang Ruan wrote: > > > Add these helper functions, and export them for filesystem use. > > > > What is the point of adding these wrappers vs just calling the > > underlying functions? > > I added them so that they can be called in a friendly way, even if > CONFIG_DAX is off. Otherwise, we need #if IS_ENABLED(CONFIG_DAX) to wrap > them where they are called. No need for wrappers, you can stub out the underlying functions as well.
diff --git a/drivers/dax/super.c b/drivers/dax/super.c index a19fcc0a54f3..acbe7078ce4c 100644 --- a/drivers/dax/super.c +++ b/drivers/dax/super.c @@ -114,6 +114,25 @@ struct dax_device *fs_dax_get_by_bdev(struct block_device *bdev, u64 *start_off) return dax_dev; } EXPORT_SYMBOL_GPL(fs_dax_get_by_bdev); + +void fs_dax_register_holder(struct dax_device *dax_dev, void *holder, + const struct dax_holder_operations *ops) +{ + dax_set_holder(dax_dev, holder, ops); +} +EXPORT_SYMBOL_GPL(fs_dax_register_holder); + +void fs_dax_unregister_holder(struct dax_device *dax_dev) +{ + dax_set_holder(dax_dev, NULL, NULL); +} +EXPORT_SYMBOL_GPL(fs_dax_unregister_holder); + +void *fs_dax_get_holder(struct dax_device *dax_dev) +{ + return dax_get_holder(dax_dev); +} +EXPORT_SYMBOL_GPL(fs_dax_get_holder); #endif /* CONFIG_BLOCK && CONFIG_FS_DAX */ enum dax_device_flags { diff --git a/include/linux/dax.h b/include/linux/dax.h index 500d048d444e..15a0ad4c248d 100644 --- a/include/linux/dax.h +++ b/include/linux/dax.h @@ -140,6 +140,10 @@ static inline void fs_put_dax(struct dax_device *dax_dev) { put_dax(dax_dev); } +void fs_dax_register_holder(struct dax_device *dax_dev, void *holder, + const struct dax_holder_operations *ops); +void fs_dax_unregister_holder(struct dax_device *dax_dev); +void *fs_dax_get_holder(struct dax_device *dax_dev); #else static inline int dax_add_host(struct dax_device *dax_dev, struct gendisk *disk) { @@ -156,6 +160,17 @@ static inline struct dax_device *fs_dax_get_by_bdev(struct block_device *bdev, static inline void fs_put_dax(struct dax_device *dax_dev) { } +static inline void fs_dax_register_holder(struct dax_device *dax_dev, + void *holder, const struct dax_holder_operations *ops) +{ +} +static inline void fs_dax_unregister_holder(struct dax_device *dax_dev) +{ +} +static inline void *fs_dax_get_holder(struct dax_device *dax_dev) +{ + return NULL; +} #endif /* CONFIG_BLOCK && CONFIG_FS_DAX */ #if IS_ENABLED(CONFIG_FS_DAX)
Add these helper functions, and export them for filesystem use. Signed-off-by: Shiyang Ruan <ruansy.fnst@fujitsu.com> --- drivers/dax/super.c | 19 +++++++++++++++++++ include/linux/dax.h | 15 +++++++++++++++ 2 files changed, 34 insertions(+)