jbd: remove dependency on __GFP_NOFAIL (05713082) · Commits · 戴 / test

The callers of start_this_handle() (or better ext3_journal_start()) are not really prepared to handle allocation failures. Such failures can for example result in silent data loss when it happens in ext3_..._writepage(). OTOH __GFP_NOFAIL is going away so we just retry allocation in start_this_handle(). This loop is potentially dangerous because the oom killer cannot be invoked for GFP_NOFS allocation, so there is a potential for infinitely looping. But still this is better than silent data loss. Signed-off-by:

Jan Kara <jack@suse.cz>

fs/jbd/transaction.c

+4 −4

Original line number	Diff line number	Diff line
		@@ -26,6 +26,7 @@
		#include <linux/mm.h>
		#include <linux/highmem.h>
		#include <linux/hrtimer.h>
		#include <linux/backing-dev.h>

		static void __journal_temp_unlink_buffer(struct journal_head *jh);

		@@ -99,11 +100,10 @@ static int start_this_handle(journal_t journal, handle_t handle)

		alloc_transaction:
		if (!journal->j_running_transaction) {
		new_transaction = kzalloc(sizeof(*new_transaction),
		GFP_NOFS\|__GFP_NOFAIL);
		new_transaction = kzalloc(sizeof(*new_transaction), GFP_NOFS);
		if (!new_transaction) {
		ret = -ENOMEM;
		goto out;
		congestion_wait(BLK_RW_ASYNC, HZ/50);
		goto alloc_transaction;
		}
		}

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