On 9/8/22 3:18 AM, Filipe Manana wrote: > > > On Thu, Sep 8, 2022 at 1:26 AM Stefan Roesch <shr@xxxxxx> wrote: >> >> From: Josef Bacik <josef@xxxxxxxxxxxxxx> >> >> For IOCB_NOWAIT we're going to want to use try lock on the extent lock, >> and simply bail if there's an ordered extent in the range because the >> only choice there is to wait for the ordered extent to complete. >> >> Signed-off-by: Josef Bacik <josef@xxxxxxxxxxxxxx> >> Signed-off-by: Stefan Roesch <shr@xxxxxx> >> --- >> fs/btrfs/ordered-data.c | 28 ++++++++++++++++++++++++++++ >> fs/btrfs/ordered-data.h | 1 + >> 2 files changed, 29 insertions(+) >> >> diff --git a/fs/btrfs/ordered-data.c b/fs/btrfs/ordered-data.c >> index 1952ac85222c..3cdfdcedb088 100644 >> --- a/fs/btrfs/ordered-data.c >> +++ b/fs/btrfs/ordered-data.c >> @@ -1041,6 +1041,34 @@ void btrfs_lock_and_flush_ordered_range(struct btrfs_inode *inode, u64 start, >> } >> } >> >> +/* >> + * btrfs_try_lock_ordered_range - lock the passed range and ensure all pending >> + * ordered extents in it are run to completion in nowait mode. >> + * >> + * @inode: Inode whose ordered tree is to be searched >> + * @start: Beginning of range to flush >> + * @end: Last byte of range to lock >> + * >> + * This function returns 1 if btrfs_lock_ordered_range does not return any >> + * extents, otherwise 0. > > Why not a bool, true/false? That's all that is needed, and it's clear. > > Thanks. > The next version of the patch series will return bool instead of int. >> + */ >> +int btrfs_try_lock_ordered_range(struct btrfs_inode *inode, u64 start, u64 end) >> +{ >> + struct btrfs_ordered_extent *ordered; >> + >> + if (!try_lock_extent(&inode->io_tree, start, end)) >> + return 0; >> + >> + ordered = btrfs_lookup_ordered_range(inode, start, end - start + 1); >> + if (!ordered) >> + return 1; >> + >> + btrfs_put_ordered_extent(ordered); >> + unlock_extent(&inode->io_tree, start, end); >> + return 0; >> +} >> + >> + >> static int clone_ordered_extent(struct btrfs_ordered_extent *ordered, u64 pos, >> u64 len) >> { >> diff --git a/fs/btrfs/ordered-data.h b/fs/btrfs/ordered-data.h >> index 87792f85e2c4..ec27ebf0af4b 100644 >> --- a/fs/btrfs/ordered-data.h >> +++ b/fs/btrfs/ordered-data.h >> @@ -218,6 +218,7 @@ void btrfs_wait_ordered_roots(struct btrfs_fs_info *fs_info, u64 nr, >> void btrfs_lock_and_flush_ordered_range(struct btrfs_inode *inode, u64 start, >> u64 end, >> struct extent_state **cached_state); >> +int btrfs_try_lock_ordered_range(struct btrfs_inode *inode, u64 start, u64 end); >> int btrfs_split_ordered_extent(struct btrfs_ordered_extent *ordered, u64 pre, >> u64 post); >> int __init ordered_data_init(void); >> -- >> 2.30.2 >>