Btrfs: stop passing a trans handle all around the reservation code

The only thing that we need to have a trans handle for is in
reserve_metadata_bytes and thats to know how much flushing we can do.  So
instead of passing it around, just check current->journal_info for a
trans_handle so we know if we can commit a transaction to try and free up space
or not.  Thanks,

Signed-off-by: Josef Bacik <josef@redhat.com>

fs/btrfs/ctree.h

@@ -2237,12 +2237,10 @@ void btrfs_init_block_rsv(struct btrfs_block_rsv *rsv);
 struct btrfs_block_rsv *btrfs_alloc_block_rsv(struct btrfs_root *root);
 void btrfs_free_block_rsv(struct btrfs_root *root,
 			  struct btrfs_block_rsv *rsv);
-int btrfs_block_rsv_add(struct btrfs_trans_handle *trans,
-			struct btrfs_root *root,
+int btrfs_block_rsv_add(struct btrfs_root *root,
 			struct btrfs_block_rsv *block_rsv,
 			u64 num_bytes);
-int btrfs_block_rsv_check(struct btrfs_trans_handle *trans,
-			  struct btrfs_root *root,
+int btrfs_block_rsv_check(struct btrfs_root *root,
 			  struct btrfs_block_rsv *block_rsv,
 			  u64 min_reserved, int min_factor, int flush);
 int btrfs_block_rsv_migrate(struct btrfs_block_rsv *src_rsv,

fs/btrfs/extent-tree.c

@@ -3404,29 +3404,34 @@ static int shrink_delalloc(struct btrfs_trans_handle *trans,
 	return reclaimed >= to_reclaim;
 }
 
-/*
- * Retries tells us how many times we've called reserve_metadata_bytes.  The
- * idea is if this is the first call (retries == 0) then we will add to our
- * reserved count if we can't make the allocation in order to hold our place
- * while we go and try and free up space.  That way for retries > 1 we don't try
- * and add space, we just check to see if the amount of unused space is >= the
- * total space, meaning that our reservation is valid.
+/**
+ * reserve_metadata_bytes - try to reserve bytes from the block_rsv's space
+ * @root - the root we're allocating for
+ * @block_rsv - the block_rsv we're allocating for
+ * @orig_bytes - the number of bytes we want
+ * @flush - wether or not we can flush to make our reservation
  *
- * However if we don't intend to retry this reservation, pass -1 as retries so
- * that it short circuits this logic.
+ * This will reserve orgi_bytes number of bytes from the space info associated
+ * with the block_rsv.  If there is not enough space it will make an attempt to
+ * flush out space to make room.  It will do this by flushing delalloc if
+ * possible or committing the transaction.  If flush is 0 then no attempts to
+ * regain reservations will be made and this will fail if there is not enough
+ * space already.
  */
-static int reserve_metadata_bytes(struct btrfs_trans_handle *trans,
-				  struct btrfs_root *root,
+static int reserve_metadata_bytes(struct btrfs_root *root,
 				  struct btrfs_block_rsv *block_rsv,
 				  u64 orig_bytes, int flush)
 {
 	struct btrfs_space_info *space_info = block_rsv->space_info;
+	struct btrfs_trans_handle *trans;
 	u64 unused;
 	u64 num_bytes = orig_bytes;
 	int retries = 0;
 	int ret = 0;
 	bool committed = false;
 	bool flushing = false;
+
+	trans = (struct btrfs_trans_handle *)current->journal_info;
 again:
 	ret = 0;
 	spin_lock(&space_info->lock);
@@ -3689,8 +3694,7 @@ void btrfs_free_block_rsv(struct btrfs_root *root,
 	kfree(rsv);
 }
 
-int btrfs_block_rsv_add(struct btrfs_trans_handle *trans,
-			struct btrfs_root *root,
+int btrfs_block_rsv_add(struct btrfs_root *root,
 			struct btrfs_block_rsv *block_rsv,
 			u64 num_bytes)
 {
@@ -3699,7 +3703,7 @@ int btrfs_block_rsv_add(struct btrfs_trans_handle *trans,
 	if (num_bytes == 0)
 		return 0;
 
-	ret = reserve_metadata_bytes(trans, root, block_rsv, num_bytes, 1);
+	ret = reserve_metadata_bytes(root, block_rsv, num_bytes, 1);
 	if (!ret) {
 		block_rsv_add_bytes(block_rsv, num_bytes, 1);
 		return 0;
@@ -3708,8 +3712,7 @@ int btrfs_block_rsv_add(struct btrfs_trans_handle *trans,
 	return ret;
 }
 
-int btrfs_block_rsv_check(struct btrfs_trans_handle *trans,
-			  struct btrfs_root *root,
+int btrfs_block_rsv_check(struct btrfs_root *root,
 			  struct btrfs_block_rsv *block_rsv,
 			  u64 min_reserved, int min_factor, int flush)
 {
@@ -3734,7 +3737,7 @@ int btrfs_block_rsv_check(struct btrfs_trans_handle *trans,
 	if (!ret)
 		return 0;
 
-	ret = reserve_metadata_bytes(trans, root, block_rsv, num_bytes, flush);
+	ret = reserve_metadata_bytes(root, block_rsv, num_bytes, flush);
 	if (!ret) {
 		block_rsv_add_bytes(block_rsv, num_bytes, 0);
 		return 0;
@@ -4034,7 +4037,7 @@ int btrfs_delalloc_reserve_metadata(struct inode *inode, u64 num_bytes)
 	to_reserve += calc_csum_metadata_size(inode, num_bytes, 1);
 	spin_unlock(&BTRFS_I(inode)->lock);
 
-	ret = reserve_metadata_bytes(NULL, root, block_rsv, to_reserve, flush);
+	ret = reserve_metadata_bytes(root, block_rsv, to_reserve, flush);
 	if (ret) {
 		u64 to_free = 0;
 		unsigned dropped;
@@ -5689,8 +5692,7 @@ use_block_rsv(struct btrfs_trans_handle *trans,
 	block_rsv = get_block_rsv(trans, root);
 
 	if (block_rsv->size == 0) {
-		ret = reserve_metadata_bytes(trans, root, block_rsv,
-					     blocksize, 0);
+		ret = reserve_metadata_bytes(root, block_rsv, blocksize, 0);
 		/*
 		 * If we couldn't reserve metadata bytes try and use some from
 		 * the global reserve.
@@ -5711,8 +5713,7 @@ use_block_rsv(struct btrfs_trans_handle *trans,
 		return block_rsv;
 	if (ret) {
 		WARN_ON(1);
-		ret = reserve_metadata_bytes(trans, root, block_rsv, blocksize,
-					     0);
+		ret = reserve_metadata_bytes(root, block_rsv, blocksize, 0);
 		if (!ret) {
 			return block_rsv;
 		} else if (ret && block_rsv != global_rsv) {

fs/btrfs/free-space-cache.c

@@ -197,9 +197,7 @@ int btrfs_truncate_free_space_cache(struct btrfs_root *root,
 
 	rsv = trans->block_rsv;
 	trans->block_rsv = root->orphan_block_rsv;
-	ret = btrfs_block_rsv_check(trans, root,
-				    root->orphan_block_rsv,
-				    0, 5, 0);
+	ret = btrfs_block_rsv_check(root, root->orphan_block_rsv, 0, 5, 0);
 	if (ret)
 		return ret;
 

fs/btrfs/inode.c

@@ -3577,7 +3577,7 @@ void btrfs_evict_inode(struct inode *inode)
 	 * doing the truncate.
 	 */
 	while (1) {
-		ret = btrfs_block_rsv_check(NULL, root, rsv, min_size, 0, 1);
+		ret = btrfs_block_rsv_check(root, rsv, min_size, 0, 1);
 		if (ret) {
 			printk(KERN_WARNING "Could not get space for a "
 			       "delete, will truncate on mount %d\n", ret);
@@ -6577,7 +6577,7 @@ static int btrfs_truncate(struct inode *inode)
 		btrfs_add_ordered_operation(trans, root, inode);
 
 	while (1) {
-		ret = btrfs_block_rsv_check(trans, root, rsv, min_size, 0, 1);
+		ret = btrfs_block_rsv_check(root, rsv, min_size, 0, 1);
 		if (ret) {
 			/*
 			 * This can only happen with the original transaction we

fs/btrfs/relocation.c

@@ -2041,8 +2041,8 @@ static noinline_for_stack int merge_reloc_root(struct reloc_control *rc,
 		BUG_ON(IS_ERR(trans));
 		trans->block_rsv = rc->block_rsv;
 
-		ret = btrfs_block_rsv_check(trans, root, rc->block_rsv,
-					    min_reserved, 0, 0);
+		ret = btrfs_block_rsv_check(root, rc->block_rsv, min_reserved,
+					    0, 0);
 		if (ret) {
 			BUG_ON(ret != -EAGAIN);
 			ret = btrfs_commit_transaction(trans, root);
@@ -2152,8 +2152,7 @@ int prepare_to_merge(struct reloc_control *rc, int err)
 again:
 	if (!err) {
 		num_bytes = rc->merging_rsv_size;
-		ret = btrfs_block_rsv_add(NULL, root, rc->block_rsv,
-					  num_bytes);
+		ret = btrfs_block_rsv_add(root, rc->block_rsv, num_bytes);
 		if (ret)
 			err = ret;
 	}
@@ -2427,7 +2426,7 @@ static int reserve_metadata_space(struct btrfs_trans_handle *trans,
 	num_bytes = calcu_metadata_size(rc, node, 1) * 2;
 
 	trans->block_rsv = rc->block_rsv;
-	ret = btrfs_block_rsv_add(trans, root, rc->block_rsv, num_bytes);
+	ret = btrfs_block_rsv_add(root, rc->block_rsv, num_bytes);
 	if (ret) {
 		if (ret == -EAGAIN)
 			rc->commit_transaction = 1;
@@ -3645,7 +3644,7 @@ int prepare_to_relocate(struct reloc_control *rc)
 	 * btrfs_init_reloc_root will use them when there
 	 * is no reservation in transaction handle.
 	 */
-	ret = btrfs_block_rsv_add(NULL, rc->extent_root, rc->block_rsv,
+	ret = btrfs_block_rsv_add(rc->extent_root, rc->block_rsv,
 				  rc->extent_root->nodesize * 256);
 	if (ret)
 		return ret;
@@ -3774,8 +3773,8 @@ static noinline_for_stack int relocate_block_group(struct reloc_control *rc)
 			}
 		}
 
-		ret = btrfs_block_rsv_check(trans, rc->extent_root,
-					    rc->block_rsv, 0, 5, 0);
+		ret = btrfs_block_rsv_check(rc->extent_root, rc->block_rsv, 0,
+					    5, 0);
 		if (ret < 0) {
 			if (ret != -EAGAIN) {
 				err = ret;

fs/btrfs/transaction.c

@@ -275,7 +275,7 @@ static struct btrfs_trans_handle *start_transaction(struct btrfs_root *root,
 	 */
 	if (num_items > 0 && root != root->fs_info->chunk_root) {
 		num_bytes = btrfs_calc_trans_metadata_size(root, num_items);
-		ret = btrfs_block_rsv_add(NULL, root,
+		ret = btrfs_block_rsv_add(root,
 					  &root->fs_info->trans_block_rsv,
 					  num_bytes);
 		if (ret)
@@ -418,8 +418,8 @@ static int should_end_transaction(struct btrfs_trans_handle *trans,
 				  struct btrfs_root *root)
 {
 	int ret;
-	ret = btrfs_block_rsv_check(trans, root,
-				    &root->fs_info->global_block_rsv, 0, 5, 0);
+	ret = btrfs_block_rsv_check(root, &root->fs_info->global_block_rsv, 0,
+				    5, 0);
 	return ret ? 1 : 0;
 }
 
@@ -914,7 +914,7 @@ static noinline int create_pending_snapshot(struct btrfs_trans_handle *trans,
 	btrfs_reloc_pre_snapshot(trans, pending, &to_reserve);
 
 	if (to_reserve > 0) {
-		ret = btrfs_block_rsv_add(trans, root, &pending->block_rsv,
+		ret = btrfs_block_rsv_add(root, &pending->block_rsv,
 					  to_reserve);
 		if (ret) {
 			pending->error = ret;