ext4: pass allocation_request struct to ext4_(alloc,splice)_branch

Instead of initializing the allocation_request structure in
ext4_alloc_branch(), set it up in ext4_ind_map_blocks(), and then pass
it to ext4_alloc_branch() and ext4_splice_branch().

This allows ext4_ind_map_blocks to pass flags in the allocation
request structure without having to add Yet Another argument to
ext4_alloc_branch().

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>

fs/ext4/indirect.c

@@ -318,34 +318,22 @@ static int ext4_blks_to_allocate(Indirect *branch, int k, unsigned int blks,
  *	ext4_alloc_block() (normally -ENOSPC). Otherwise we set the chain
  *	as described above and return 0.
  */
-static int ext4_alloc_branch(handle_t *handle, struct inode *inode,
-			     ext4_lblk_t iblock, int indirect_blks,
-			     int *blks, ext4_fsblk_t goal,
-			     ext4_lblk_t *offsets, Indirect *branch)
+static int ext4_alloc_branch(handle_t *handle,
+			     struct ext4_allocation_request *ar,
+			     int indirect_blks, ext4_lblk_t *offsets,
+			     Indirect *branch)
 {
-	struct ext4_allocation_request	ar;
 	struct buffer_head *		bh;
 	ext4_fsblk_t			b, new_blocks[4];
 	__le32				*p;
 	int				i, j, err, len = 1;
 
-	/*
-	 * Set up for the direct block allocation
-	 */
-	memset(&ar, 0, sizeof(ar));
-	ar.inode = inode;
-	ar.len = *blks;
-	ar.logical = iblock;
-	if (S_ISREG(inode->i_mode))
-		ar.flags = EXT4_MB_HINT_DATA;
-
 	for (i = 0; i <= indirect_blks; i++) {
 		if (i == indirect_blks) {
-			ar.goal = goal;
-			new_blocks[i] = ext4_mb_new_blocks(handle, &ar, &err);
+			new_blocks[i] = ext4_mb_new_blocks(handle, ar, &err);
 		} else
-			goal = new_blocks[i] = ext4_new_meta_blocks(handle, inode,
-							goal, 0, NULL, &err);
+			ar->goal = new_blocks[i] = ext4_new_meta_blocks(handle,
+				    ar->inode, ar->goal, 0, NULL, &err);
 		if (err) {
 			i--;
 			goto failed;
@@ -354,7 +342,7 @@ static int ext4_alloc_branch(handle_t *handle, struct inode *inode,
 		if (i == 0)
 			continue;
 
-		bh = branch[i].bh = sb_getblk(inode->i_sb, new_blocks[i-1]);
+		bh = branch[i].bh = sb_getblk(ar->inode->i_sb, new_blocks[i-1]);
 		if (unlikely(!bh)) {
 			err = -ENOMEM;
 			goto failed;
@@ -372,7 +360,7 @@ static int ext4_alloc_branch(handle_t *handle, struct inode *inode,
 		b = new_blocks[i];
 
 		if (i == indirect_blks)
-			len = ar.len;
+			len = ar->len;
 		for (j = 0; j < len; j++)
 			*p++ = cpu_to_le32(b++);
 
@@ -381,11 +369,10 @@ static int ext4_alloc_branch(handle_t *handle, struct inode *inode,
 		unlock_buffer(bh);
 
 		BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata");
-		err = ext4_handle_dirty_metadata(handle, inode, bh);
+		err = ext4_handle_dirty_metadata(handle, ar->inode, bh);
 		if (err)
 			goto failed;
 	}
-	*blks = ar.len;
 	return 0;
 failed:
 	for (; i >= 0; i--) {
@@ -396,10 +383,10 @@ failed:
 		 * existing before ext4_alloc_branch() was called.
 		 */
 		if (i > 0 && i != indirect_blks && branch[i].bh)
-			ext4_forget(handle, 1, inode, branch[i].bh,
+			ext4_forget(handle, 1, ar->inode, branch[i].bh,
 				    branch[i].bh->b_blocknr);
-		ext4_free_blocks(handle, inode, NULL, new_blocks[i],
-				 (i == indirect_blks) ? ar.len : 1, 0);
+		ext4_free_blocks(handle, ar->inode, NULL, new_blocks[i],
+				 (i == indirect_blks) ? ar->len : 1, 0);
 	}
 	return err;
 }
@@ -419,9 +406,9 @@ failed:
  * inode (->i_blocks, etc.). In case of success we end up with the full
  * chain to new block and return 0.
  */
-static int ext4_splice_branch(handle_t *handle, struct inode *inode,
-			      ext4_lblk_t block, Indirect *where, int num,
-			      int blks)
+static int ext4_splice_branch(handle_t *handle,
+			      struct ext4_allocation_request *ar,
+			      Indirect *where, int num)
 {
 	int i;
 	int err = 0;
@@ -446,9 +433,9 @@ static int ext4_splice_branch(handle_t *handle, struct inode *inode,
 	 * Update the host buffer_head or inode to point to more just allocated
 	 * direct blocks blocks
 	 */
-	if (num == 0 && blks > 1) {
+	if (num == 0 && ar->len > 1) {
 		current_block = le32_to_cpu(where->key) + 1;
-		for (i = 1; i < blks; i++)
+		for (i = 1; i < ar->len; i++)
 			*(where->p + i) = cpu_to_le32(current_block++);
 	}
 
@@ -465,14 +452,14 @@ static int ext4_splice_branch(handle_t *handle, struct inode *inode,
 		 */
 		jbd_debug(5, "splicing indirect only\n");
 		BUFFER_TRACE(where->bh, "call ext4_handle_dirty_metadata");
-		err = ext4_handle_dirty_metadata(handle, inode, where->bh);
+		err = ext4_handle_dirty_metadata(handle, ar->inode, where->bh);
 		if (err)
 			goto err_out;
 	} else {
 		/*
 		 * OK, we spliced it into the inode itself on a direct block.
 		 */
-		ext4_mark_inode_dirty(handle, inode);
+		ext4_mark_inode_dirty(handle, ar->inode);
 		jbd_debug(5, "splicing direct\n");
 	}
 	return err;
@@ -484,11 +471,11 @@ err_out:
 		 * need to revoke the block, which is why we don't
 		 * need to set EXT4_FREE_BLOCKS_METADATA.
 		 */
-		ext4_free_blocks(handle, inode, where[i].bh, 0, 1,
+		ext4_free_blocks(handle, ar->inode, where[i].bh, 0, 1,
 				 EXT4_FREE_BLOCKS_FORGET);
 	}
-	ext4_free_blocks(handle, inode, NULL, le32_to_cpu(where[num].key),
-			 blks, 0);
+	ext4_free_blocks(handle, ar->inode, NULL, le32_to_cpu(where[num].key),
+			 ar->len, 0);
 
 	return err;
 }
@@ -525,11 +512,11 @@ int ext4_ind_map_blocks(handle_t *handle, struct inode *inode,
 			struct ext4_map_blocks *map,
 			int flags)
 {
+	struct ext4_allocation_request ar;
 	int err = -EIO;
 	ext4_lblk_t offsets[4];
 	Indirect chain[4];
 	Indirect *partial;
-	ext4_fsblk_t goal;
 	int indirect_blks;
 	int blocks_to_boundary = 0;
 	int depth;
@@ -579,7 +566,14 @@ int ext4_ind_map_blocks(handle_t *handle, struct inode *inode,
 		return -ENOSPC;
 	}
 
-	goal = ext4_find_goal(inode, map->m_lblk, partial);
+	/* Set up for the direct block allocation */
+	memset(&ar, 0, sizeof(ar));
+	ar.inode = inode;
+	ar.logical = map->m_lblk;
+	if (S_ISREG(inode->i_mode))
+		ar.flags = EXT4_MB_HINT_DATA;
+
+	ar.goal = ext4_find_goal(inode, map->m_lblk, partial);
 
 	/* the number of blocks need to allocate for [d,t]indirect blocks */
 	indirect_blks = (chain + depth) - partial - 1;
@@ -588,13 +582,13 @@ int ext4_ind_map_blocks(handle_t *handle, struct inode *inode,
 	 * Next look up the indirect map to count the totoal number of
 	 * direct blocks to allocate for this branch.
 	 */
-	count = ext4_blks_to_allocate(partial, indirect_blks,
-				      map->m_len, blocks_to_boundary);
+	ar.len = ext4_blks_to_allocate(partial, indirect_blks,
+				       map->m_len, blocks_to_boundary);
+
 	/*
 	 * Block out ext4_truncate while we alter the tree
 	 */
-	err = ext4_alloc_branch(handle, inode, map->m_lblk, indirect_blks,
-				&count, goal,
+	err = ext4_alloc_branch(handle, &ar, indirect_blks,
 				offsets + (partial - chain), partial);
 
 	/*
@@ -605,14 +599,14 @@ int ext4_ind_map_blocks(handle_t *handle, struct inode *inode,
 	 * may need to return -EAGAIN upwards in the worst case.  --sct
 	 */
 	if (!err)
-		err = ext4_splice_branch(handle, inode, map->m_lblk,
-					 partial, indirect_blks, count);
+		err = ext4_splice_branch(handle, &ar, partial, indirect_blks);
 	if (err)
 		goto cleanup;
 
 	map->m_flags |= EXT4_MAP_NEW;
 
 	ext4_update_inode_fsync_trans(handle, inode, 1);
+	count = ar.len;
 got_it:
 	map->m_flags |= EXT4_MAP_MAPPED;
 	map->m_pblk = le32_to_cpu(chain[depth-1].key);