[Ocfs2-devel] [Patch] for bug 88, touch&chmod file cause hang.

[Ling, Xiaofeng]

When you touch a file, in the call sequence,
sys_utime->notify_change->ocfs_setattr, before notify_change,
there is a "down(&inode->i_sem)", so in ocfs_setattr, when down again,
it causes dead lock.
I guess it should use the priv_sem instead. see the patch, it can work.

Index: file.c
===================================================================
--- file.c	(revision 1022)
+++ file.c	(working copy)
@@ -1347,7 +1347,7 @@
 	/* NOTE: Other filesystems get away without locking this, but
 	 * we're clustered and this has to hit disk now... */
 	if (!(attr->ia_valid & ATTR_SIZE))
-		down(&inode->i_sem);
+		down (&(OCFS_I(inode)->priv_sem));
 
 	if (!dentry->d_parent || !dentry->d_parent->d_inode) {
 		LOG_ERROR_STR ("bad inode or root inode");
@@ -1449,7 +1449,7 @@
 
 bail:
 	if (!(attr->ia_valid & ATTR_SIZE))
-		up(&inode->i_sem);
+		up (&(OCFS_I(inode)->priv_sem));
 
 #ifndef BH_SEM_LEAK_CHECKING
 	if (error < 0)

bug 88 description

kernel 2.6.6
mount a ocfs2 file system and then do:
cd /ocfs
touch /ocfs/a
the command hangs. system not hang.

The call trace:

touch         D C036B74C     0  1593   1227                     (NOTLB)
ccf4fe6c 00000082 00000246 c036b74c ccc9c484 00000000 d08cc25c d08cc25c 
       cd1fa200 cfebf680 ccc9c484 00000001 cd086400 0001f061 805bbf22
000000b1 
       cd8fefd8 cd1da868 00000286 cd8fee30 cd1da870 c0354af0 00000001
cd8fee30 
Call Trace:
 [<d08cc25c>] ocfs_bh_sem_lookup+0x1d7/0x3ad [ocfs2]
 [<d08cc25c>] ocfs_bh_sem_lookup+0x1d7/0x3ad [ocfs2]
 [<c0354af0>] __down+0x7c/0xc7
 [<c011269c>] default_wake_function+0x0/0x12
 [<c0354c44>] __down_failed+0x8/0xc
 [<d08cbe3f>] .text.lock.file+0x181/0x186 [ocfs2]
 [<c015c95c>] notify_change+0x153/0x187
 [<c0143ecb>] sys_utime+0x105/0x181
 [<d08c6fd8>] ocfs_file_open+0x0/0x7aa [ocfs2]
 [<d08c7b4f>] ocfs_file_release+0x3cd/0x415 [ocfs2]
 [<c0146304>] __fput+0xa5/0xfb
 [<c0103e5f>] syscall_call+0x7/0xb