diff options
-rw-r--r-- | fs/fs-writeback.c | 78 | ||||
-rw-r--r-- | include/linux/backing-dev.h | 2 |
2 files changed, 39 insertions, 41 deletions
diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c index 0655767..ae45f77 100644 --- a/fs/fs-writeback.c +++ b/fs/fs-writeback.c @@ -25,6 +25,45 @@ #include <linux/buffer_head.h> #include "internal.h" + +/** + * writeback_acquire - attempt to get exclusive writeback access to a device + * @bdi: the device's backing_dev_info structure + * + * It is a waste of resources to have more than one pdflush thread blocked on + * a single request queue. Exclusion at the request_queue level is obtained + * via a flag in the request_queue's backing_dev_info.state. + * + * Non-request_queue-backed address_spaces will share default_backing_dev_info, + * unless they implement their own. Which is somewhat inefficient, as this + * may prevent concurrent writeback against multiple devices. + */ +static int writeback_acquire(struct backing_dev_info *bdi) +{ + return !test_and_set_bit(BDI_pdflush, &bdi->state); +} + +/** + * writeback_in_progress - determine whether there is writeback in progress + * @bdi: the device's backing_dev_info structure. + * + * Determine whether there is writeback in progress against a backing device. + */ +int writeback_in_progress(struct backing_dev_info *bdi) +{ + return test_bit(BDI_pdflush, &bdi->state); +} + +/** + * writeback_release - relinquish exclusive writeback access against a device. + * @bdi: the device's backing_dev_info structure + */ +static void writeback_release(struct backing_dev_info *bdi) +{ + BUG_ON(!writeback_in_progress(bdi)); + clear_bit(BDI_pdflush, &bdi->state); +} + /** * __mark_inode_dirty - internal function * @inode: inode to mark @@ -747,43 +786,4 @@ int generic_osync_inode(struct inode *inode, struct address_space *mapping, int return err; } - EXPORT_SYMBOL(generic_osync_inode); - -/** - * writeback_acquire - attempt to get exclusive writeback access to a device - * @bdi: the device's backing_dev_info structure - * - * It is a waste of resources to have more than one pdflush thread blocked on - * a single request queue. Exclusion at the request_queue level is obtained - * via a flag in the request_queue's backing_dev_info.state. - * - * Non-request_queue-backed address_spaces will share default_backing_dev_info, - * unless they implement their own. Which is somewhat inefficient, as this - * may prevent concurrent writeback against multiple devices. - */ -int writeback_acquire(struct backing_dev_info *bdi) -{ - return !test_and_set_bit(BDI_pdflush, &bdi->state); -} - -/** - * writeback_in_progress - determine whether there is writeback in progress - * @bdi: the device's backing_dev_info structure. - * - * Determine whether there is writeback in progress against a backing device. - */ -int writeback_in_progress(struct backing_dev_info *bdi) -{ - return test_bit(BDI_pdflush, &bdi->state); -} - -/** - * writeback_release - relinquish exclusive writeback access against a device. - * @bdi: the device's backing_dev_info structure - */ -void writeback_release(struct backing_dev_info *bdi) -{ - BUG_ON(!writeback_in_progress(bdi)); - clear_bit(BDI_pdflush, &bdi->state); -} diff --git a/include/linux/backing-dev.h b/include/linux/backing-dev.h index 48a62ba..b66fa2b 100644 --- a/include/linux/backing-dev.h +++ b/include/linux/backing-dev.h @@ -156,9 +156,7 @@ static inline unsigned long bdi_stat_error(struct backing_dev_info *bdi) extern struct backing_dev_info default_backing_dev_info; void default_unplug_io_fn(struct backing_dev_info *bdi, struct page *page); -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) { |