diff options
Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/backing-dev.h | 21 |
1 files changed, 19 insertions, 2 deletions
diff --git a/include/linux/backing-dev.h b/include/linux/backing-dev.h index 94c93c9c5f66..e34916ddd1d7 100644 --- a/include/linux/backing-dev.h +++ b/include/linux/backing-dev.h @@ -20,10 +20,14 @@ enum bdi_state { BDI_unused, /* Available bits start here */ }; +typedef int (congested_fn)(void *, int); + struct backing_dev_info { unsigned long ra_pages; /* max readahead in PAGE_CACHE_SIZE units */ unsigned long state; /* Always use atomic bitops on this */ int memory_backed; /* Cannot clean pages with writepage */ + congested_fn *congested_fn; /* Function pointer if device is md/dm */ + void *congested_data; /* Pointer to aux data for congested func */ }; extern struct backing_dev_info default_backing_dev_info; @@ -32,14 +36,27 @@ int writeback_acquire(struct backing_dev_info *bdi); int writeback_in_progress(struct backing_dev_info *bdi); void writeback_release(struct backing_dev_info *bdi); +static inline int bdi_congested(struct backing_dev_info *bdi, int bdi_bits) +{ + if (bdi->congested_fn) + return bdi->congested_fn(bdi->congested_data, bdi_bits); + return (bdi->state & bdi_bits); +} + static inline int bdi_read_congested(struct backing_dev_info *bdi) { - return test_bit(BDI_read_congested, &bdi->state); + return bdi_congested(bdi, 1 << BDI_read_congested); } static inline int bdi_write_congested(struct backing_dev_info *bdi) { - return test_bit(BDI_write_congested, &bdi->state); + return bdi_congested(bdi, 1 << BDI_write_congested); +} + +static inline int bdi_rw_congested(struct backing_dev_info *bdi) +{ + return bdi_congested(bdi, (1 << BDI_read_congested)| + (1 << BDI_write_congested)); } #endif /* _LINUX_BACKING_DEV_H */ |