From 80f9d24130e45b01984a918d6b2006c10687b138 Mon Sep 17 00:00:00 2001 From: Josef Bacik Date: Mon, 12 Sep 2022 12:27:46 -0700 Subject: btrfs: make btrfs_check_nocow_lock nowait compatible Now all the helpers that btrfs_check_nocow_lock uses handle nowait, add a nowait flag to btrfs_check_nocow_lock so it can be used by the write path. Reviewed-by: Filipe Manana Signed-off-by: Josef Bacik Signed-off-by: Stefan Roesch Signed-off-by: David Sterba --- fs/btrfs/file.c | 33 ++++++++++++++++++++++----------- 1 file changed, 22 insertions(+), 11 deletions(-) (limited to 'fs/btrfs/file.c') diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c index 94a9b47d5ae5..c7edac473381 100644 --- a/fs/btrfs/file.c +++ b/fs/btrfs/file.c @@ -1480,7 +1480,7 @@ lock_and_cleanup_extent_if_need(struct btrfs_inode *inode, struct page **pages, * NOTE: Callers need to call btrfs_check_nocow_unlock() if we return > 0. */ int btrfs_check_nocow_lock(struct btrfs_inode *inode, loff_t pos, - size_t *write_bytes) + size_t *write_bytes, bool nowait) { struct btrfs_fs_info *fs_info = inode->root->fs_info; struct btrfs_root *root = inode->root; @@ -1499,16 +1499,21 @@ int btrfs_check_nocow_lock(struct btrfs_inode *inode, loff_t pos, fs_info->sectorsize) - 1; num_bytes = lockend - lockstart + 1; - btrfs_lock_and_flush_ordered_range(inode, lockstart, lockend, NULL); + if (nowait) { + if (!btrfs_try_lock_ordered_range(inode, lockstart, lockend)) { + btrfs_drew_write_unlock(&root->snapshot_lock); + return -EAGAIN; + } + } else { + btrfs_lock_and_flush_ordered_range(inode, lockstart, lockend, NULL); + } ret = can_nocow_extent(&inode->vfs_inode, lockstart, &num_bytes, - NULL, NULL, NULL, false, false); - if (ret <= 0) { - ret = 0; + NULL, NULL, NULL, nowait, false); + if (ret <= 0) btrfs_drew_write_unlock(&root->snapshot_lock); - } else { + else *write_bytes = min_t(size_t, *write_bytes , num_bytes - pos + lockstart); - } unlock_extent(&inode->io_tree, lockstart, lockend, NULL); return ret; @@ -1665,16 +1670,22 @@ static noinline ssize_t btrfs_buffered_write(struct kiocb *iocb, &data_reserved, pos, write_bytes, false); if (ret < 0) { + int can_nocow; + /* * If we don't have to COW at the offset, reserve * metadata only. write_bytes may get smaller than * requested here. */ - if (btrfs_check_nocow_lock(BTRFS_I(inode), pos, - &write_bytes) > 0) - only_release_metadata = true; - else + can_nocow = btrfs_check_nocow_lock(BTRFS_I(inode), pos, + &write_bytes, false); + if (can_nocow < 0) + ret = can_nocow; + if (can_nocow > 0) + ret = 0; + if (ret) break; + only_release_metadata = true; } num_pages = DIV_ROUND_UP(write_bytes + offset, PAGE_SIZE); -- cgit v1.2.3