Commit 773bc4f3 authored by Ryusuke Konishi's avatar Ryusuke Konishi
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nilfs2: add barrier mount option 



Nilfs enables write barriers by default and has "nobarrier" mount
option to disable this feature.  But it lacks the complementary option
and has no way to re-enable the feature on remount.

This adds "barrier" option to resolve this imbalance.

Signed-off-by: default avatarRyusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
parent 32502047

Documentation/filesystems/nilfs2.txt

+4 −1
Original line number Diff line number Diff line
@@ -49,7 +49,10 @@ Mount options 
NILFS2 supports the following mount options:

(*) == default



nobarrier		Disables barriers.

barrier(*)		This enables/disables the use of write barriers.  This

nobarrier		requires an IO stack which can support barriers, and

			if nilfs gets an error on a barrier write, it will

			disable again with a warning.

errors=continue		Keep going on a filesystem error.

errors=remount-ro(*)	Remount the filesystem read-only on an error.

errors=panic		Panic and halt the machine if an error occurs.

fs/nilfs2/super.c

+5 −1
Original line number Diff line number Diff line
@@ -603,7 +603,7 @@ static const struct export_operations nilfs_export_ops = { 


enum {

	Opt_err_cont, Opt_err_panic, Opt_err_ro,

	Opt_nobarrier, Opt_snapshot, Opt_order, Opt_norecovery,

	Opt_barrier, Opt_nobarrier, Opt_snapshot, Opt_order, Opt_norecovery,

	Opt_discard, Opt_err,

};
@@ -611,6 +611,7 @@ static match_table_t tokens = { 
	{Opt_err_cont, "errors=continue"},

	{Opt_err_panic, "errors=panic"},

	{Opt_err_ro, "errors=remount-ro"},

	{Opt_barrier, "barrier"},

	{Opt_nobarrier, "nobarrier"},

	{Opt_snapshot, "cp=%u"},

	{Opt_order, "order=%s"},
@@ -636,6 +637,9 @@ static int parse_options(char *options, struct super_block *sb) 


		token = match_token(p, tokens, args);

		switch (token) {

		case Opt_barrier:

			nilfs_set_opt(sbi, BARRIER);

			break;

		case Opt_nobarrier:

			nilfs_clear_opt(sbi, BARRIER);

			break;