From ef7f38359ea8b3e9c7f2cae9a4d4935f55ca9e80 Mon Sep 17 00:00:00 2001 From: Kalpak Shah Date: Wed, 18 Jul 2007 09:15:20 -0400 Subject: ext4: Add nanosecond timestamps This patch adds nanosecond timestamps for ext4. This involves adding *time_extra fields to the ext4_inode to extend the timestamps to 64-bits. Creation time is also added by this patch. These extended fields will fit into an inode if the filesystem was formatted with large inodes (-I 256 or larger) and there are currently no EAs consuming all of the available space. For new inodes we always reserve enough space for the kernel's known extended fields, but for inodes created with an old kernel this might not have been the case. So this patch also adds the EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE feature flag(ro-compat so that older kernels can't create inodes with a smaller extra_isize). which indicates if the fields fitting inside s_min_extra_isize are available or not. If the expansion of inodes if unsuccessful then this feature will be disabled. This feature is only enabled if requested by the sysadmin. None of the extended inode fields is critical for correct filesystem operation. Signed-off-by: Andreas Dilger Signed-off-by: Kalpak Shah Signed-off-by: Eric Sandeen Signed-off-by: Dave Kleikamp Signed-off-by: Mingming Cao Signed-off-by: "Theodore Ts'o" --- fs/ext4/super.c | 28 ++++++++++++++++++++++++++++ 1 file changed, 28 insertions(+) (limited to 'fs/ext4/super.c') diff --git a/fs/ext4/super.c b/fs/ext4/super.c index af0835187e76..b47259f6f39c 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -1651,6 +1651,8 @@ static int ext4_fill_super (struct super_block *sb, void *data, int silent) sbi->s_inode_size); goto failed_mount; } + if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) + sb->s_time_gran = 1 << (EXT4_EPOCH_BITS - 2); } sbi->s_frag_size = EXT4_MIN_FRAG_SIZE << le32_to_cpu(es->s_log_frag_size); @@ -1874,6 +1876,32 @@ static int ext4_fill_super (struct super_block *sb, void *data, int silent) } ext4_setup_super (sb, es, sb->s_flags & MS_RDONLY); + + /* determine the minimum size of new large inodes, if present */ + if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) { + sbi->s_want_extra_isize = sizeof(struct ext4_inode) - + EXT4_GOOD_OLD_INODE_SIZE; + if (EXT4_HAS_RO_COMPAT_FEATURE(sb, + EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE)) { + if (sbi->s_want_extra_isize < + le16_to_cpu(es->s_want_extra_isize)) + sbi->s_want_extra_isize = + le16_to_cpu(es->s_want_extra_isize); + if (sbi->s_want_extra_isize < + le16_to_cpu(es->s_min_extra_isize)) + sbi->s_want_extra_isize = + le16_to_cpu(es->s_min_extra_isize); + } + } + /* Check if enough inode space is available */ + if (EXT4_GOOD_OLD_INODE_SIZE + sbi->s_want_extra_isize > + sbi->s_inode_size) { + sbi->s_want_extra_isize = sizeof(struct ext4_inode) - + EXT4_GOOD_OLD_INODE_SIZE; + printk(KERN_INFO "EXT4-fs: required extra inode space not" + "available.\n"); + } + /* * akpm: core read_super() calls in here with the superblock locked. * That deadlocks, because orphan cleanup needs to lock the superblock -- cgit v1.2.3