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| author | Pankaj Gupta <pagupta@redhat.com> | 2019-07-05 19:33:26 +0530 |
|---|---|---|
| committer | Dan Williams <dan.j.williams@intel.com> | 2019-07-05 15:19:10 -0700 |
| commit | 32de1484648a837db5dea0a7007fe7136804e392 (patch) | |
| tree | 268cebd1e247ac532948188ceab4bed7c903b18c /include/linux/dax.h | |
| parent | 2e9ee0955d3c2d3db56aa02ba6f948ba35d5e9c1 (diff) | |
| download | lwn-32de1484648a837db5dea0a7007fe7136804e392.tar.gz lwn-32de1484648a837db5dea0a7007fe7136804e392.zip | |
dax: check synchronous mapping is supported
This patch introduces 'daxdev_mapping_supported' helper
which checks if 'MAP_SYNC' is supported with filesystem
mapping. It also checks if corresponding dax_device is
synchronous. Virtio pmem device is asynchronous and
does not not support VM_SYNC.
Suggested-by: Jan Kara <jack@suse.cz>
Signed-off-by: Pankaj Gupta <pagupta@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Diffstat (limited to 'include/linux/dax.h')
| -rw-r--r-- | include/linux/dax.h | 17 |
1 files changed, 17 insertions, 0 deletions
diff --git a/include/linux/dax.h b/include/linux/dax.h index 8b535bc4526f..9bd8528bd305 100644 --- a/include/linux/dax.h +++ b/include/linux/dax.h @@ -56,6 +56,18 @@ static inline void set_dax_synchronous(struct dax_device *dax_dev) { __set_dax_synchronous(dax_dev); } +/* + * Check if given mapping is supported by the file / underlying device. + */ +static inline bool daxdev_mapping_supported(struct vm_area_struct *vma, + struct dax_device *dax_dev) +{ + if (!(vma->vm_flags & VM_SYNC)) + return true; + if (!IS_DAX(file_inode(vma->vm_file))) + return false; + return dax_synchronous(dax_dev); +} #else static inline struct dax_device *dax_get_by_host(const char *host) { @@ -90,6 +102,11 @@ static inline bool dax_synchronous(struct dax_device *dax_dev) static inline void set_dax_synchronous(struct dax_device *dax_dev) { } +static inline bool daxdev_mapping_supported(struct vm_area_struct *vma, + struct dax_device *dax_dev) +{ + return !(vma->vm_flags & VM_SYNC); +} #endif struct writeback_control; |