diff options
| author | John Groves <john@groves.net> | 2026-03-27 21:05:12 +0000 |
|---|---|---|
| committer | Ira Weiny <ira.weiny@intel.com> | 2026-03-30 08:20:48 -0500 |
| commit | eec38f5d86d27535509c99f02ccc642ceb0c3e2a (patch) | |
| tree | cd91e965d44ca6817c625f4c191d5962fbcee09a /include/linux | |
| parent | 700ecbc1f5aa02ba9ad68d7be1ef7a9c8eae07e9 (diff) | |
dax: Add fs_dax_get() func to prepare dax for fs-dax usage
The fs_dax_get() function should be called by fs-dax file systems after
opening a fsdev dax device. This adds holder_operations, which provides
a memory failure callback path and effects exclusivity between callers
of fs_dax_get().
fs_dax_get() is specific to fsdev_dax, so it checks the driver type
(which required touching bus.[ch]). fs_dax_get() fails if fsdev_dax is
not bound to the memory.
This function serves the same role as fs_dax_get_by_bdev(), which dax
file systems call after opening the pmem block device.
This can't be located in fsdev.c because struct dax_device is opaque
there.
This will be called by fs/fuse/famfs.c in a subsequent commit.
Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: John Groves <john@groves.net>
Link: https://patch.msgid.link/0100019d311d8750-75395c22-031b-4d5f-aebe-790dca656b87-000000@email.amazonses.com
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/dax.h | 16 |
1 files changed, 12 insertions, 4 deletions
diff --git a/include/linux/dax.h b/include/linux/dax.h index b19bfe0c2fd1..a85e270bfb3c 100644 --- a/include/linux/dax.h +++ b/include/linux/dax.h @@ -130,7 +130,6 @@ int dax_add_host(struct dax_device *dax_dev, struct gendisk *disk); void dax_remove_host(struct gendisk *disk); struct dax_device *fs_dax_get_by_bdev(struct block_device *bdev, u64 *start_off, void *holder, const struct dax_holder_operations *ops); -void fs_put_dax(struct dax_device *dax_dev, void *holder); #else static inline int dax_add_host(struct dax_device *dax_dev, struct gendisk *disk) { @@ -145,12 +144,12 @@ static inline struct dax_device *fs_dax_get_by_bdev(struct block_device *bdev, { return NULL; } -static inline void fs_put_dax(struct dax_device *dax_dev, void *holder) -{ -} #endif /* CONFIG_BLOCK && CONFIG_FS_DAX */ #if IS_ENABLED(CONFIG_FS_DAX) +void fs_put_dax(struct dax_device *dax_dev, void *holder); +int fs_dax_get(struct dax_device *dax_dev, void *holder, + const struct dax_holder_operations *hops); int dax_writeback_mapping_range(struct address_space *mapping, struct dax_device *dax_dev, struct writeback_control *wbc); int dax_folio_reset_order(struct folio *folio); @@ -164,6 +163,15 @@ dax_entry_t dax_lock_mapping_entry(struct address_space *mapping, void dax_unlock_mapping_entry(struct address_space *mapping, unsigned long index, dax_entry_t cookie); #else +static inline void fs_put_dax(struct dax_device *dax_dev, void *holder) +{ +} + +static inline int fs_dax_get(struct dax_device *dax_dev, void *holder, + const struct dax_holder_operations *hops) +{ + return -EOPNOTSUPP; +} static inline struct page *dax_layout_busy_page(struct address_space *mapping) { return NULL; |