Hi,
generic_osync_inode() (called by generic_file_write()) is not checking if
the inode being synced has the I_LOCK bit set before checking the I_DIRTY
bit.
AFAICS, the following problem can happen:
sync()
...
sync_one()
reset I_DIRTY, set I_LOCK
filemap_fdatasync() <-- #window
write_inode() <-- #window
filemap_fdatawait() <-- #window
unset I_LOCK
There is no guarantee that the inode is fully synced until sync_one()
cleans the inode I_LOCK bit.
If generic_osync_inode() checks the I_DIRTY bit (and sees it clean) during
"#window", an "O_SYNC write()" call may return to userspace without having
all the data actually synced.
If I'm not missing something here this patch should the problem.
Comments?
--- fs/inode.c~ Thu Mar 22 16:04:13 2001
+++ fs/inode.c Thu Apr 12 15:18:22 2001
@@ -347,6 +347,11 @@
#endif
spin_lock(&inode_lock);
+ while (inode->i_state & I_LOCK) {
+ spin_unlock(&inode_lock);
+ __wait_on_inode(inode);
+ spin_lock(&inode_lock);
+ }
if (!(inode->i_state & I_DIRTY))
goto out;
if (datasync && !(inode->i_state & I_DIRTY_DATASYNC))
-
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This archive was generated by hypermail 2b29 : Sun Apr 15 2001 - 21:00:19 EST