diff options
Diffstat (limited to 'include/linux/backing-dev.h')
| -rw-r--r-- | include/linux/backing-dev.h | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/include/linux/backing-dev.h b/include/linux/backing-dev.h index f41ca8486e02..7360e79e9a2f 100644 --- a/include/linux/backing-dev.h +++ b/include/linux/backing-dev.h @@ -122,6 +122,8 @@ int bdi_set_max_ratio(struct backing_dev_info *bdi, unsigned int max_ratio); * BDI_CAP_STRICTLIMIT: Keep number of dirty pages below bdi threshold. * * BDI_CAP_CGROUP_WRITEBACK: Supports cgroup-aware writeback. + * BDI_CAP_SYNCHRONOUS_IO: Device is so fast that asynchronous IO would be + * inefficient. */ #define BDI_CAP_NO_ACCT_DIRTY 0x00000001 #define BDI_CAP_NO_WRITEBACK 0x00000002 @@ -129,6 +131,7 @@ int bdi_set_max_ratio(struct backing_dev_info *bdi, unsigned int max_ratio); #define BDI_CAP_STABLE_WRITES 0x00000008 #define BDI_CAP_STRICTLIMIT 0x00000010 #define BDI_CAP_CGROUP_WRITEBACK 0x00000020 +#define BDI_CAP_SYNCHRONOUS_IO 0x00000040 #define BDI_CAP_NO_ACCT_AND_WRITEBACK \ (BDI_CAP_NO_WRITEBACK | BDI_CAP_NO_ACCT_DIRTY | BDI_CAP_NO_ACCT_WB) @@ -174,6 +177,11 @@ static inline int wb_congested(struct bdi_writeback *wb, int cong_bits) long congestion_wait(int sync, long timeout); long wait_iff_congested(struct pglist_data *pgdat, int sync, long timeout); +static inline bool bdi_cap_synchronous_io(struct backing_dev_info *bdi) +{ + return bdi->capabilities & BDI_CAP_SYNCHRONOUS_IO; +} + static inline bool bdi_cap_stable_pages_required(struct backing_dev_info *bdi) { return bdi->capabilities & BDI_CAP_STABLE_WRITES; |