diff mbox series

[v9,2/9] ext4: add fast_commit feature and handling for extended mount options

Message ID 20200919005451.3899779-3-harshadshirwadkar@gmail.com
State Superseded
Headers show
Series ext4: add fast commits feature | expand

Commit Message

harshad shirwadkar Sept. 19, 2020, 12:54 a.m. UTC 
We are running out of mount option bits. Add handling for using
s_mount_opt2. Add ext4 and jbd2 fast commit feature flag and also add
ability to turn on / off the fast commit feature in Ext4.

Signed-off-by: Harshad Shirwadkar <harshadshirwadkar@gmail.com>
---
 fs/ext4/ext4.h       |  4 ++++
 fs/ext4/super.c      | 24 +++++++++++++++++++-----
 include/linux/jbd2.h |  5 ++++-
 3 files changed, 27 insertions(+), 6 deletions(-)

Comments

Theodore Ts'o Oct. 9, 2020, 5:58 p.m. UTC | #1 
On Fri, Sep 18, 2020 at 05:54:44PM -0700, Harshad Shirwadkar wrote:
> We are running out of mount option bits. Add handling for using
> s_mount_opt2. Add ext4 and jbd2 fast commit feature flag and also add
> ability to turn on / off the fast commit feature in Ext4.

Shouldn't that read "...ability to turn off the fast commit feature via a
mount option"?

> @@ -2207,10 +2211,17 @@ static int handle_mount_opt(struct super_block *sb, char *opt, int token,
>  			WARN_ON(1);
>  			return -1;
>  		}
> -		if (arg != 0)
> -			sbi->s_mount_opt |= m->mount_opt;
> -		else
> -			sbi->s_mount_opt &= ~m->mount_opt;
> +		if (m->flags & MOPT_2) {
> +			if (arg != 0)
> +				sbi->s_mount_opt2 |= m->mount_opt;
> +			else
> +				sbi->s_mount_opt2 &= ~m->mount_opt;
> +		} else {
> +			if (arg != 0)
> +				sbi->s_mount_opt |= m->mount_opt;
> +			else
> +				sbi->s_mount_opt &= ~m->mount_opt;
> +		}
>  	}
>  	return 1;
>  }


This requires a matching change in _ext4_show_options(), so that the
MOPT_2 options are properly displayed in /proc/mounts.

						- Ted
harshad shirwadkar Oct. 13, 2020, 12:27 a.m. UTC | #2 
On Fri, Oct 9, 2020 at 10:58 AM Theodore Y. Ts'o <tytso@mit.edu> wrote:
>
> On Fri, Sep 18, 2020 at 05:54:44PM -0700, Harshad Shirwadkar wrote:
> > We are running out of mount option bits. Add handling for using
> > s_mount_opt2. Add ext4 and jbd2 fast commit feature flag and also add
> > ability to turn on / off the fast commit feature in Ext4.
>
> Shouldn't that read "...ability to turn off the fast commit feature via a
> mount option"?
>
> > @@ -2207,10 +2211,17 @@ static int handle_mount_opt(struct super_block *sb, char *opt, int token,
> >                       WARN_ON(1);
> >                       return -1;
> >               }
> > -             if (arg != 0)
> > -                     sbi->s_mount_opt |= m->mount_opt;
> > -             else
> > -                     sbi->s_mount_opt &= ~m->mount_opt;
> > +             if (m->flags & MOPT_2) {
> > +                     if (arg != 0)
> > +                             sbi->s_mount_opt2 |= m->mount_opt;
> > +                     else
> > +                             sbi->s_mount_opt2 &= ~m->mount_opt;
> > +             } else {
> > +                     if (arg != 0)
> > +                             sbi->s_mount_opt |= m->mount_opt;
> > +                     else
> > +                             sbi->s_mount_opt &= ~m->mount_opt;
> > +             }
> >       }
> >       return 1;
> >  }
>
>
> This requires a matching change in _ext4_show_options(), so that the
> MOPT_2 options are properly displayed in /proc/mounts.
Thanks for pointing that out, I'll add this in V10.

Thanks,
Harshad
>
>                                                 - Ted
diff mbox series

Patch

diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index 523e00d7b392..82e889d5c2ed 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -1214,6 +1214,8 @@  struct ext4_inode_info {
 #define EXT4_MOUNT2_EXPLICIT_JOURNAL_CHECKSUM	0x00000008 /* User explicitly
 						specified journal checksum */
 
+#define EXT4_MOUNT2_JOURNAL_FAST_COMMIT	0x00000010 /* Journal fast commit */
+
 #define clear_opt(sb, opt)		EXT4_SB(sb)->s_mount_opt &= \
 						~EXT4_MOUNT_##opt
 #define set_opt(sb, opt)		EXT4_SB(sb)->s_mount_opt |= \
@@ -1814,6 +1816,7 @@  static inline bool ext4_verity_in_progress(struct inode *inode)
 #define EXT4_FEATURE_COMPAT_RESIZE_INODE	0x0010
 #define EXT4_FEATURE_COMPAT_DIR_INDEX		0x0020
 #define EXT4_FEATURE_COMPAT_SPARSE_SUPER2	0x0200
+#define EXT4_FEATURE_COMPAT_FAST_COMMIT		0x0400
 #define EXT4_FEATURE_COMPAT_STABLE_INODES	0x0800
 
 #define EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER	0x0001
@@ -1916,6 +1919,7 @@  EXT4_FEATURE_COMPAT_FUNCS(xattr,		EXT_ATTR)
 EXT4_FEATURE_COMPAT_FUNCS(resize_inode,		RESIZE_INODE)
 EXT4_FEATURE_COMPAT_FUNCS(dir_index,		DIR_INDEX)
 EXT4_FEATURE_COMPAT_FUNCS(sparse_super2,	SPARSE_SUPER2)
+EXT4_FEATURE_COMPAT_FUNCS(fast_commit,		FAST_COMMIT)
 EXT4_FEATURE_COMPAT_FUNCS(stable_inodes,	STABLE_INODES)
 
 EXT4_FEATURE_RO_COMPAT_FUNCS(sparse_super,	SPARSE_SUPER)
diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 13bdddc081e0..b62858ee420b 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -1526,7 +1526,7 @@  enum {
 	Opt_dioread_nolock, Opt_dioread_lock,
 	Opt_discard, Opt_nodiscard, Opt_init_itable, Opt_noinit_itable,
 	Opt_max_dir_size_kb, Opt_nojournal_checksum, Opt_nombcache,
-	Opt_prefetch_block_bitmaps,
+	Opt_prefetch_block_bitmaps, Opt_no_fc,
 };
 
 static const match_table_t tokens = {
@@ -1613,6 +1613,7 @@  static const match_table_t tokens = {
 	{Opt_init_itable, "init_itable=%u"},
 	{Opt_init_itable, "init_itable"},
 	{Opt_noinit_itable, "noinit_itable"},
+	{Opt_no_fc, "no_fc"},
 	{Opt_max_dir_size_kb, "max_dir_size_kb=%u"},
 	{Opt_test_dummy_encryption, "test_dummy_encryption=%s"},
 	{Opt_test_dummy_encryption, "test_dummy_encryption"},
@@ -1738,6 +1739,7 @@  static int clear_qf_name(struct super_block *sb, int qtype)
 #define MOPT_EXT4_ONLY	(MOPT_NO_EXT2 | MOPT_NO_EXT3)
 #define MOPT_STRING	0x0400
 #define MOPT_SKIP	0x0800
+#define	MOPT_2		0x1000
 
 static const struct mount_opts {
 	int	token;
@@ -1838,6 +1840,8 @@  static const struct mount_opts {
 	{Opt_nombcache, EXT4_MOUNT_NO_MBCACHE, MOPT_SET},
 	{Opt_prefetch_block_bitmaps, EXT4_MOUNT_PREFETCH_BLOCK_BITMAPS,
 	 MOPT_SET},
+	{Opt_no_fc, EXT4_MOUNT2_JOURNAL_FAST_COMMIT,
+	 MOPT_CLEAR | MOPT_2 | MOPT_EXT4_ONLY},
 	{Opt_err, 0, 0}
 };
 
@@ -2207,10 +2211,17 @@  static int handle_mount_opt(struct super_block *sb, char *opt, int token,
 			WARN_ON(1);
 			return -1;
 		}
-		if (arg != 0)
-			sbi->s_mount_opt |= m->mount_opt;
-		else
-			sbi->s_mount_opt &= ~m->mount_opt;
+		if (m->flags & MOPT_2) {
+			if (arg != 0)
+				sbi->s_mount_opt2 |= m->mount_opt;
+			else
+				sbi->s_mount_opt2 &= ~m->mount_opt;
+		} else {
+			if (arg != 0)
+				sbi->s_mount_opt |= m->mount_opt;
+			else
+				sbi->s_mount_opt &= ~m->mount_opt;
+		}
 	}
 	return 1;
 }
@@ -3924,6 +3935,8 @@  static int ext4_fill_super(struct super_block *sb, void *data, int silent)
 #ifdef CONFIG_EXT4_FS_POSIX_ACL
 	set_opt(sb, POSIX_ACL);
 #endif
+	if (ext4_has_feature_fast_commit(sb))
+		set_opt2(sb, JOURNAL_FAST_COMMIT);
 	/* don't forget to enable journal_csum when metadata_csum is enabled. */
 	if (ext4_has_metadata_csum(sb))
 		set_opt(sb, JOURNAL_CHECKSUM);
@@ -4576,6 +4589,7 @@  static int ext4_fill_super(struct super_block *sb, void *data, int silent)
 		sbi->s_def_mount_opt &= ~EXT4_MOUNT_JOURNAL_CHECKSUM;
 		clear_opt(sb, JOURNAL_CHECKSUM);
 		clear_opt(sb, DATA_FLAGS);
+		clear_opt2(sb, JOURNAL_FAST_COMMIT);
 		sbi->s_journal = NULL;
 		needs_recovery = 0;
 		goto no_journal;
diff --git a/include/linux/jbd2.h b/include/linux/jbd2.h
index a756a4cdf939..f438257d7f31 100644
--- a/include/linux/jbd2.h
+++ b/include/linux/jbd2.h
@@ -288,6 +288,7 @@  typedef struct journal_superblock_s
 #define JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT	0x00000004
 #define JBD2_FEATURE_INCOMPAT_CSUM_V2		0x00000008
 #define JBD2_FEATURE_INCOMPAT_CSUM_V3		0x00000010
+#define JBD2_FEATURE_INCOMPAT_FAST_COMMIT	0x00000020
 
 /* See "journal feature predicate functions" below */
 
@@ -298,7 +299,8 @@  typedef struct journal_superblock_s
 					JBD2_FEATURE_INCOMPAT_64BIT | \
 					JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT | \
 					JBD2_FEATURE_INCOMPAT_CSUM_V2 | \
-					JBD2_FEATURE_INCOMPAT_CSUM_V3)
+					JBD2_FEATURE_INCOMPAT_CSUM_V3 | \
+					JBD2_FEATURE_INCOMPAT_FAST_COMMIT)
 
 #ifdef __KERNEL__
 
@@ -1239,6 +1241,7 @@  JBD2_FEATURE_INCOMPAT_FUNCS(64bit,		64BIT)
 JBD2_FEATURE_INCOMPAT_FUNCS(async_commit,	ASYNC_COMMIT)
 JBD2_FEATURE_INCOMPAT_FUNCS(csum2,		CSUM_V2)
 JBD2_FEATURE_INCOMPAT_FUNCS(csum3,		CSUM_V3)
+JBD2_FEATURE_INCOMPAT_FUNCS(fast_commit,	FAST_COMMIT)
 
 /*
  * Journal flag definitions