Commit 1a89734d authored Apr 29, 2008 by Aneesh Kumar K.V Committed by Theodore Ts'o Apr 29, 2008

ext4: Return unwritten buffer head when trying to read from prealloc space.



ext4_ext_get_blocks() returns the number of blocks allocated with buffer
head unmapped for a read from prealloc space.  This is needed so that
delayed allocation doesn't do block reservation for prealloc space
since the blocks are already reserved on disk.  Mark the buffer head
unwritten.  Some code paths try to read the block if the buffer_head is
not new and no uptodate.  Marking the buffer head unwritten avoids this
reading.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

parent e067ba00

fs/ext4/extents.c

+2 −0

Original line number	Diff line number	Diff line
		@@ -2580,6 +2580,8 @@ int ext4_ext_get_blocks(handle_t handle, struct inode inode,
		*/
		if (allocated > max_blocks)
		allocated = max_blocks;
		/* mark the buffer unwritten */
		__set_bit(BH_Unwritten, &bh_result->b_state);
		goto out2;
		}

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