[JFFS2] Fix jffs2_reserve_space() when all blocks are pending erasure.

When _all_ the blocks were on the erase_pending_list, we could't find a
block to GC from but there was no _actually_ free space, and
jffs2_reserve_space() would get a little unhappy.

Handle this case by returning -EAGAIN from jffs2_garbage_collect_pass().
There are two callers of that function -- jffs2_flush_wbuf_gc(), which
will interpret it as an error and flush the writebuffer by other means,
and jffs2_reserve_space(), which we modify to respond to -EAGAIN with an
immediate call to jffs2_erase_pending_blocks() and another run round the
loop.

Signed-off-by: David Woodhouse <dwmw2@infradead.org>

1 files changed, 4 insertions, 1 deletions

diff --git a/fs/jffs2/nodemgmt.c b/fs/jffs2/nodemgmt.c
index 747a73f0aa4d..9df8f3ef20df 100644
--- a/fs/jffs2/nodemgmt.c
+++ b/fs/jffs2/nodemgmt.c
@@ -116,7 +116,10 @@ int jffs2_reserve_space(struct jffs2_sb_info *c, uint32_t minsize,
                         spin_unlock(&c->erase_completion_lock);
 
                         ret = jffs2_garbage_collect_pass(c);
-                        if (ret)
+
+                        if (ret == -EAGAIN)
+                                jffs2_erase_pending_blocks(c, 1);
+                        else if (ret)
                                 return ret;
 
                         cond_resched();