[PATCH 1/2] ext4: remove lazytime/nolazytime mount options handled by MS_LAZYTIME

[PATCH 1/2] ext4: remove lazytime/nolazytime mount options handled by MS_LAZYTIME

[Lukas Czerner]

The lazytime and nolazytime mount options were added temporarily back in
2015 with commit a26f49926da9 ("ext4: add optimization for the lazytime
mount option"). It think it has been enough time for the util-linux with
lazytime support to get widely used. Remove the mount options.

Signed-off-by: Lukas Czerner <lczerner@redhat.com>
---
 fs/ext4/super.c | 13 ++-----------
 1 file changed, 2 insertions(+), 11 deletions(-)

diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 71f7f866de58..0fc511d16b6d 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -1703,8 +1703,7 @@ enum {
 	Opt_usrquota, Opt_grpquota, Opt_prjquota, Opt_i_version,
 	Opt_dax, Opt_dax_always, Opt_dax_inode, Opt_dax_never,
 	Opt_stripe, Opt_delalloc, Opt_nodelalloc, Opt_warn_on_error,
-	Opt_nowarn_on_error, Opt_mblk_io_submit,
-	Opt_lazytime, Opt_nolazytime, Opt_debug_want_extra_isize,
+	Opt_nowarn_on_error, Opt_mblk_io_submit, Opt_debug_want_extra_isize,
 	Opt_nomblk_io_submit, Opt_block_validity, Opt_noblock_validity,
 	Opt_inode_readahead_blks, Opt_journal_ioprio,
 	Opt_dioread_nolock, Opt_dioread_lock,
@@ -1818,8 +1817,6 @@ static const struct fs_parameter_spec ext4_param_specs[] = {
 	fsparam_flag	("nodelalloc",		Opt_nodelalloc),
 	fsparam_flag	("warn_on_error",	Opt_warn_on_error),
 	fsparam_flag	("nowarn_on_error",	Opt_nowarn_on_error),
-	fsparam_flag	("lazytime",		Opt_lazytime),
-	fsparam_flag	("nolazytime",		Opt_nolazytime),
 	fsparam_u32	("debug_want_extra_isize",
 						Opt_debug_want_extra_isize),
 	fsparam_flag	("mblk_io_submit",	Opt_removed),
@@ -2244,12 +2241,6 @@ static int ext4_parse_param(struct fs_context *fc, struct fs_parameter *param)
 	case Opt_i_version:
 		ctx_set_flags(ctx, SB_I_VERSION);
 		return 0;
-	case Opt_lazytime:
-		ctx_set_flags(ctx, SB_LAZYTIME);
-		return 0;
-	case Opt_nolazytime:
-		ctx_clear_flags(ctx, SB_LAZYTIME);
-		return 0;
 	case Opt_inlinecrypt:
 #ifdef CONFIG_FS_ENCRYPTION_INLINE_CRYPT
 		ctx_set_flags(ctx, SB_INLINECRYPT);
@@ -6261,7 +6252,7 @@ static int __ext4_remount(struct fs_context *fc, struct super_block *sb,
 	 * either way we need to make sure it matches in both *flags and
 	 * s_flags. Copy those selected flags from *flags to s_flags
 	 */
-	vfs_flags = SB_LAZYTIME | SB_I_VERSION;
+	vfs_flags = SB_I_VERSION;
 	sb->s_flags = (sb->s_flags & ~vfs_flags) | (*flags & vfs_flags);
 
 	ext4_apply_options(fc, sb);
-- 
2.31.1

[PATCH 2/2] ext4: fix i_version handling on remount

[Lukas Czerner]

i_version mount option is getting lost on remount. This is because the
'i_version' mount option differs from the util-linux mount option
'iversion', but it has exactly the same functionality. We have to
specifically notify the vfs that this is what we want by setting
appropriate flag in fc->sb_flags. Fix it and as a result we can remove
*flags argument from __ext4_remount(); do the same for
__ext4_fill_super().

In addition set out to deprecate ext4 specific 'i_version' mount option
in favor or 'iversion' by kernel version 5.20.

Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Fixes: cebe85d570cf ("ext4: switch to the new mount api")
---
 fs/ext4/super.c | 43 ++++++++++++++++++-------------------------
 1 file changed, 18 insertions(+), 25 deletions(-)

diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 0fc511d16b6d..053b25c6b05c 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -2239,6 +2239,8 @@ static int ext4_parse_param(struct fs_context *fc, struct fs_parameter *param)
 		ctx_set_mount_flags(ctx, EXT4_MF_FS_ABORTED);
 		return 0;
 	case Opt_i_version:
+		ext4_msg(NULL, KERN_WARNING, deprecated_msg, param->key, "5.20");
+		ext4_msg(NULL, KERN_WARNING, "Use iversion instead\n");
 		ctx_set_flags(ctx, SB_I_VERSION);
 		return 0;
 	case Opt_inlinecrypt:
@@ -2868,6 +2870,14 @@ static int ext4_apply_options(struct fs_context *fc, struct super_block *sb)
 	sb->s_flags &= ~ctx->mask_s_flags;
 	sb->s_flags |= ctx->vals_s_flags;
 
+	/*
+	 * i_version differs from common mount option iversion so we have
+	 * to let vfs know that it was set, otherwise it would get cleared
+	 * on remount
+	 */
+	if (ctx->mask_s_flags & SB_I_VERSION)
+		fc->sb_flags |= SB_I_VERSION;
+
 #define APPLY(X) ({ if (ctx->spec & EXT4_SPEC_##X) sbi->X = ctx->X; })
 	APPLY(s_commit_interval);
 	APPLY(s_stripe);
@@ -4335,8 +4345,7 @@ static struct ext4_sb_info *ext4_alloc_sbi(struct super_block *sb)
 	return NULL;
 }
 
-static int __ext4_fill_super(struct fs_context *fc, struct super_block *sb,
-			     int silent)
+static int __ext4_fill_super(struct fs_context *fc, struct super_block *sb)
 {
 	struct buffer_head *bh, **group_desc;
 	struct ext4_super_block *es = NULL;
@@ -4356,6 +4365,7 @@ static int __ext4_fill_super(struct fs_context *fc, struct super_block *sb,
 	int err = 0;
 	ext4_group_t first_not_zeroed;
 	struct ext4_fs_context *ctx = fc->fs_private;
+	int silent = fc->sb_flags & SB_SILENT;
 
 	/* Set defaults for the variables that will be set during parsing */
 	ctx->journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
@@ -5542,7 +5552,7 @@ static int ext4_fill_super(struct super_block *sb, struct fs_context *fc)
 	if (ctx->spec & EXT4_SPEC_s_sb_block)
 		sbi->s_sb_block = ctx->s_sb_block;
 
-	ret = __ext4_fill_super(fc, sb, fc->sb_flags & SB_SILENT);
+	ret = __ext4_fill_super(fc, sb);
 	if (ret < 0)
 		goto free_sbi;
 
@@ -6201,13 +6211,12 @@ struct ext4_mount_options {
 #endif
 };
 
-static int __ext4_remount(struct fs_context *fc, struct super_block *sb,
-			  int *flags)
+static int __ext4_remount(struct fs_context *fc, struct super_block *sb)
 {
 	struct ext4_fs_context *ctx = fc->fs_private;
 	struct ext4_super_block *es;
 	struct ext4_sb_info *sbi = EXT4_SB(sb);
-	unsigned long old_sb_flags, vfs_flags;
+	unsigned long old_sb_flags;
 	struct ext4_mount_options old_opts;
 	ext4_group_t g;
 	int err = 0;
@@ -6247,14 +6256,6 @@ static int __ext4_remount(struct fs_context *fc, struct super_block *sb,
 		ctx->journal_ioprio =
 			sbi->s_journal->j_task->io_context->ioprio;
 
-	/*
-	 * Some options can be enabled by ext4 and/or by VFS mount flag
-	 * either way we need to make sure it matches in both *flags and
-	 * s_flags. Copy those selected flags from *flags to s_flags
-	 */
-	vfs_flags = SB_I_VERSION;
-	sb->s_flags = (sb->s_flags & ~vfs_flags) | (*flags & vfs_flags);
-
 	ext4_apply_options(fc, sb);
 
 	if ((old_opts.s_mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) ^
@@ -6308,13 +6309,13 @@ static int __ext4_remount(struct fs_context *fc, struct super_block *sb,
 	/* Flush outstanding errors before changing fs state */
 	flush_work(&sbi->s_error_work);
 
-	if ((bool)(*flags & SB_RDONLY) != sb_rdonly(sb)) {
+	if ((bool)(fc->sb_flags & SB_RDONLY) != sb_rdonly(sb)) {
 		if (ext4_test_mount_flag(sb, EXT4_MF_FS_ABORTED)) {
 			err = -EROFS;
 			goto restore_opts;
 		}
 
-		if (*flags & SB_RDONLY) {
+		if (fc->sb_flags & SB_RDONLY) {
 			err = sync_filesystem(sb);
 			if (err < 0)
 				goto restore_opts;
@@ -6462,13 +6463,6 @@ static int __ext4_remount(struct fs_context *fc, struct super_block *sb,
 	if (!ext4_has_feature_mmp(sb) || sb_rdonly(sb))
 		ext4_stop_mmpd(sbi);
 
-	/*
-	 * Some options can be enabled by ext4 and/or by VFS mount flag
-	 * either way we need to make sure it matches in both *flags and
-	 * s_flags. Copy those selected flags from s_flags to *flags
-	 */
-	*flags = (*flags & ~vfs_flags) | (sb->s_flags & vfs_flags);
-
 	return 0;
 
 restore_opts:
@@ -6500,7 +6494,6 @@ static int __ext4_remount(struct fs_context *fc, struct super_block *sb,
 static int ext4_reconfigure(struct fs_context *fc)
 {
 	struct super_block *sb = fc->root->d_sb;
-	int flags = fc->sb_flags;
 	int ret;
 
 	fc->s_fs_info = EXT4_SB(sb);
@@ -6509,7 +6502,7 @@ static int ext4_reconfigure(struct fs_context *fc)
 	if (ret < 0)
 		return ret;
 
-	ret = __ext4_remount(fc, sb, &flags);
+	ret = __ext4_remount(fc, sb);
 	if (ret < 0)
 		return ret;
 
-- 
2.31.1

Re: [PATCH 1/2] ext4: remove lazytime/nolazytime mount options handled by MS_LAZYTIME

[Theodore Ts'o]

On Wed, 22 Dec 2021 11:45:16 +0100, Lukas Czerner wrote:
> The lazytime and nolazytime mount options were added temporarily back in
> 2015 with commit a26f49926da9 ("ext4: add optimization for the lazytime
> mount option"). It think it has been enough time for the util-linux with
> lazytime support to get widely used. Remove the mount options.
> 
> 

Applied, thanks!

[1/2] ext4: remove lazytime/nolazytime mount options handled by MS_LAZYTIME
      commit: 4437992be7ca3ac5dd0a62cad10357112d4fb43e
[2/2] ext4: fix i_version handling on remount
      commit: 960e0ab63b2e5d8476bc873743f812e9e90cd047

Best regards,
-- 
Theodore Ts'o <tytso@mit.edu>