UPSTREAM: ext4: check for shutdown and r/o file system in ext4_write_inode()

If the file system has been shut down or is read-only, then
ext4_write_inode() needs to bail out early.

Also use jbd2_complete_transaction() instead of ext4_force_commit() so
we only force a commit if it is needed.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
(cherry picked from commit 18f2c4fcebf2582f96cbd5f2238f4f354a0e4847)
Signed-off-by: Aditya Kali <adityakali@google.com>

BUG=b:118491168
TEST=trybots, filestore tests
Reviewed-on: https://chromium-review.googlesource.com/1386167
Commit-Ready: ChromeOS CL Exonerator Bot <chromiumos-cl-exonerator@appspot.gserviceaccount.com>
Tested-by: Aditya Kali <adityakali@google.com>
Reviewed-by: Guenter Roeck <groeck@chromium.org>

(cherry picked from commit d91485df8108e453db6b9d76108a7e1c66bd3824)

Change-Id: I0c30701716cf71d6695f30d1d37b08ca692dae5d
Reviewed-on: https://chromium-review.googlesource.com/c/1386172
Tested-by: Aditya Kali <adityakali@google.com>
Commit-Queue: Aditya Kali <adityakali@google.com>
Reviewed-by: Guenter Roeck <groeck@chromium.org>
1 file changed