exofs: Write sbi->s_nextid as part of the Create command

Before when creating a new inode, we'd set the sb->s_dirt flag,
and sometime later the system would write out s_nextid as part
of the sb_info. Also on inode sync we would force the sb sync
as well.

Define the s_nextid as a new partition attribute and set it
every time we create a new object.
At mount we read it from it's new place.

We now never set sb->s_dirt anywhere in exofs. write_super
is actually never called. The call to exofs_write_super from
exofs_put_super is also removed because the VFS always calls
->sync_fs before calling ->put_super twice.

To stay backward-and-forward compatible we also write the old
s_nextid in the super_block object at unmount, and support zero
length attribute on mount.

This also fixes a BUG where in layouts when group_width was not
a divisor of EXOFS_SUPER_ID (0x10000) the s_nextid was not read
from the device it was written to. Because of the sliding window
layout trick, and because the read was always done from the 0
device but the write was done via the raid engine that might slide
the device view. Now we read and write through the raid engine.

Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>

1 files changed, 1 insertions, 10 deletions

diff --git a/fs/exofs/file.c b/fs/exofs/file.c
index 4c0d6bac9143..45ca323d8363 100644
--- a/fs/exofs/file.c
+++ b/fs/exofs/file.c
@@ -45,17 +45,8 @@ static int exofs_release_file(struct inode *inode, struct file *filp)
 static int exofs_file_fsync(struct file *filp, int datasync)
 {
         int ret;
-        struct inode *inode = filp->f_mapping->host;
-        struct super_block *sb;
-
-        ret = sync_inode_metadata(inode, 1);
-
-        /* This is a good place to write the sb */
-        /* TODO: Sechedule an sb-sync on create */
-        sb = inode->i_sb;
-        if (sb->s_dirt)
-                exofs_sync_fs(sb, 1);
 
+        ret = sync_inode_metadata(filp->f_mapping->host, 1);
         return ret;
 }