1 files changed, 29 insertions, 7 deletions

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index bddbae7..f089d7d 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -4480,8 +4480,19 @@ search_again:
 		if (found_type > min_type) {
 			del_item = 1;
 		} else {
-			if (item_end < new_size)
+			if (item_end < new_size) {
+				/*
+				 * With NO_HOLES mode, for the following mapping
+				 *
+				 * [0-4k][hole][8k-12k]
+				 *
+				 * if truncating isize down to 6k, it ends up
+				 * isize being 8k.
+				 */
+				if (btrfs_fs_incompat(root->fs_info, NO_HOLES))
+					last_size = new_size;
 				break;
+			}
 			if (found_key.offset >= new_size)
 				del_item = 1;
 			else
@@ -7235,7 +7246,6 @@ static struct extent_map *btrfs_create_dio_extent(struct inode *inode,
 	struct extent_map *em = NULL;
 	int ret;
 
-	down_read(&BTRFS_I(inode)->dio_sem);
 	if (type != BTRFS_ORDERED_NOCOW) {
 		em = create_pinned_em(inode, start, len, orig_start,
 				      block_start, block_len, orig_block_len,
@@ -7254,7 +7264,6 @@ static struct extent_map *btrfs_create_dio_extent(struct inode *inode,
 		em = ERR_PTR(ret);
 	}
  out:
-	up_read(&BTRFS_I(inode)->dio_sem);
 
 	return em;
 }
@@ -7639,11 +7648,18 @@ static void adjust_dio_outstanding_extents(struct inode *inode,
 	 * within our reservation, otherwise we need to adjust our inode
 	 * counter appropriately.
 	 */
-	if (dio_data->outstanding_extents) {
+	if (dio_data->outstanding_extents >= num_extents) {
 		dio_data->outstanding_extents -= num_extents;
 	} else {
+		/*
+		 * If dio write length has been split due to no large enough
+		 * contiguous space, we need to compensate our inode counter
+		 * appropriately.
+		 */
+		u64 num_needed = num_extents - dio_data->outstanding_extents;
+
 		spin_lock(&BTRFS_I(inode)->lock);
-		BTRFS_I(inode)->outstanding_extents += num_extents;
+		BTRFS_I(inode)->outstanding_extents += num_needed;
 		spin_unlock(&BTRFS_I(inode)->lock);
 	}
 }
@@ -8034,8 +8050,10 @@ next_block_or_try_again:
 
 		start += sectorsize;
 
-		if (nr_sectors--) {
+		nr_sectors--;
+		if (nr_sectors) {
 			pgoff += sectorsize;
+			ASSERT(pgoff < PAGE_SIZE);
 			goto next_block_or_try_again;
 		}
 	}
@@ -8141,8 +8159,10 @@ next:
 
 		ASSERT(nr_sectors);
 
-		if (--nr_sectors) {
+		nr_sectors--;
+		if (nr_sectors) {
 			pgoff += sectorsize;
+			ASSERT(pgoff < PAGE_SIZE);
 			goto next_block;
 		}
 	}
@@ -8707,6 +8727,7 @@ static ssize_t btrfs_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
 		dio_data.unsubmitted_oe_range_start = (u64)offset;
 		dio_data.unsubmitted_oe_range_end = (u64)offset;
 		current->journal_info = &dio_data;
+		down_read(&BTRFS_I(inode)->dio_sem);
 	} else if (test_bit(BTRFS_INODE_READDIO_NEED_LOCK,
 				     &BTRFS_I(inode)->runtime_flags)) {
 		inode_dio_end(inode);
@@ -8719,6 +8740,7 @@ static ssize_t btrfs_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
 				   iter, btrfs_get_blocks_direct, NULL,
 				   btrfs_submit_direct, flags);
 	if (iov_iter_rw(iter) == WRITE) {
+		up_read(&BTRFS_I(inode)->dio_sem);
 		current->journal_info = NULL;
 		if (ret < 0 && ret != -EIOCBQUEUED) {
 			if (dio_data.reserve)