ext4: Properly count journal credits for long symlinks
authorEric Sandeen <sandeen@redhat.com>
Thu, 11 Aug 2011 14:54:31 +0000 (09:54 -0500)
committerLinus Torvalds <torvalds@linux-foundation.org>
Fri, 12 Aug 2011 00:23:40 +0000 (17:23 -0700)
commit8c20871998c082f6fbc963f1449a5ba5140ee39a
treebbc61fb11c8e9f5e02843dbf20bded2c01430ac6
parentd2db60df1e7eb39cf0f378dfc4dd8813666d46ef
ext4: Properly count journal credits for long symlinks

Commit df5e6223407e ("ext4: fix deadlock in ext4_symlink() in ENOSPC
conditions") recalculated the number of credits needed for a long
symlink, in the process of splitting it into two transactions.  However,
the first credit calculation under-counted because if selinux is
enabled, credits are needed to create the selinux xattr as well.

Overrunning the reservation will result in an OOPS in
jbd2_journal_dirty_metadata() due to this assert:

  J_ASSERT_JH(jh, handle->h_buffer_credits > 0);

Fix this by increasing the reservation size.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
fs/ext4/namei.c