jbd2: Remove __GFP_NOFAIL from jbd2 layer

__GFP_NOFAIL is going away, so add our own retry loop.  Also add
jbd2__journal_start() and jbd2__journal_restart() which take a gfp
mask, so that file systems can optionally (re)start transaction
handles using GFP_KERNEL.  If they do this, then they need to be
prepared to handle receiving an PTR_ERR(-ENOMEM) error, and be ready
to reflect that error up to userspace.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

1 files changed, 3 insertions, 1 deletions

diff --git a/include/linux/jbd2.h b/include/linux/jbd2.h
index a4d2e9f7088a..5a72bc75b273 100644
--- a/include/linux/jbd2.h
+++ b/include/linux/jbd2.h
@@ -1081,7 +1081,9 @@ static inline handle_t *journal_current_handle(void)
  */
 
 extern handle_t *jbd2_journal_start(journal_t *, int nblocks);
-extern int       jbd2_journal_restart (handle_t *, int nblocks);
+extern handle_t *jbd2__journal_start(journal_t *, int nblocks, int gfp_mask);
+extern int       jbd2_journal_restart(handle_t *, int nblocks);
+extern int       jbd2__journal_restart(handle_t *, int nblocks, int gfp_mask);
 extern int       jbd2_journal_extend (handle_t *, int nblocks);
 extern int       jbd2_journal_get_write_access(handle_t *, struct buffer_head *);
 extern int       jbd2_journal_get_create_access (handle_t *, struct buffer_head *);