2.4.23-pre8-pac1 and since: NFSv3 problem

[Greg Louis <glouis@dynamicro.on.ca>]

This is still present in kernel 2.4.23-pac1.

On 20031115 (Sat) at 0055:23 +0100, J.A. Magallon wrote:
> 
> On 11.15, J.A. Magallon wrote:
> > 
> > On 11.11, Greg Louis wrote:
> > > On 20031111 (Tue) at 1326:47 -0500, Greg Louis wrote:
> > > > Kernels 2.4.23-pre7-pac1 and 2.4.23-rc1 are ok but -pre8-pac1 and
> > > > -rc1-pac1 behave as follows: mounting a remote directory via NFS with
> > > > v3 enabled (client and server) seems to work ok, and running mount with
> > > > no parameters shows the NFS mount, but any attempt at access fails with
> > > > a message like
> > > >   /bin/ls: reading directory /whatever/it/was: Input/output error
> > > 
> > > Reverting all changes to fs/nfs/* since 2.4.23-pre7-pac1, and only
> > > those, corrects the problem.
> > > 
> > 
> > /metoo
> > 
> > annwn:~> bpsh 0 mount   
> > none on /proc type proc (rw)
> > none on /dev/pts type devpts (rw,mode=0620)
> > none on /dev/shm type tmpfs (rw)
> > none on /tmp type tmpfs (rw)
> > 192.168.0.1:/lib on /lib type nfs (ro,noatime,nfsvers=3,nolock,addr=192.168.0.1)
> > 192.168.0.1:/bin on /bin type nfs (ro,noatime,nfsvers=3,nolock,addr=192.168.0.1)
> > 192.168.0.1:/sbin on /sbin type nfs (ro,noatime,nfsvers=3,nolock,addr=192.168.0.1)
> > 192.168.0.1:/usr on /usr type nfs (ro,noatime,nfsvers=3,nolock,addr=192.168.0.1)
> > 192.168.0.1:/opt on /opt type nfs (ro,noatime,nfsvers=3,nolock,addr=192.168.0.1)
> > 192.168.0.1:/home on /home type nfs (rw,nfsvers=3,noac,addr=192.168.0.1)
> > 192.168.0.1:/work on /work/shared type nfs (rw,nfsvers=3,noac,addr=192.168.0.1)
> > 
> > annwn:~> bpsh 0 pwd
> > /home/magallon
> > 
> > annwn:~> bpsh 0 ls
> > ls: reading directory .: Invalid argument
> > 
> > It works for some time, and then it breaks.
> > Could you send me the patch you used to revert those changes ?
> > I will try to make a diff from rc1 to pre7 and reverse.
> 
> Just this (pre7 -> pre8|rc1):
> 
> diff -ruN linux-2.4.23-pre7/fs/nfs/nfs3proc.c linux-2.4.23-rc1/fs/nfs/nfs3proc.c
> --- linux-2.4.23-pre7/fs/nfs/nfs3proc.c	2003-08-25 13:44:43.000000000 +0200
> +++ linux-2.4.23-rc1/fs/nfs/nfs3proc.c	2003-11-12 11:07:48.000000000 +0100
> @@ -433,8 +433,6 @@
>   * The decode function itself doesn't perform any decoding, it just makes
>   * sure the reply is syntactically correct.
>   *
> - * Also note that this implementation handles both plain readdir and
> - * readdirplus.
>   */
>  static int
>  nfs3_proc_readdir(struct inode *dir, struct rpc_cred *cred,
> @@ -448,11 +446,7 @@
>  	struct rpc_message	msg = { NFS3PROC_READDIR, &arg, &res, cred };
>  	int			status;
>  
> -	if (plus)
> -		msg.rpc_proc = NFS3PROC_READDIRPLUS;
> -
> -	dprintk("NFS call  readdir%s %d\n",
> -			plus? "plus" : "", (unsigned int) cookie);
> +	dprintk("NFS call  readdir %d\n", (unsigned int) cookie);
>  
>  	dir_attr.valid = 0;
>  	status = rpc_call_sync(NFS_CLIENT(dir), &msg, 0);
> diff -ruN linux-2.4.23-pre7/fs/nfs/nfs3xdr.c linux-2.4.23-rc1/fs/nfs/nfs3xdr.c
> --- linux-2.4.23-pre7/fs/nfs/nfs3xdr.c	2002-11-29 00:53:15.000000000 +0100
> +++ linux-2.4.23-rc1/fs/nfs/nfs3xdr.c	2003-11-12 11:07:48.000000000 +0100
> @@ -599,8 +599,6 @@
>  u32 *
>  nfs3_decode_dirent(u32 *p, struct nfs_entry *entry, int plus)
>  {
> -	struct nfs_entry old = *entry;
> -
>  	if (!*p++) {
>  		if (!*p)
>  			return ERR_PTR(-EAGAIN);
> @@ -616,20 +614,12 @@
>  	p = xdr_decode_hyper(p, &entry->cookie);
>  
>  	if (plus) {
> -		p = xdr_decode_post_op_attr(p, &entry->fattr);
> +		struct nfs_fattr fattr;
> +		p = xdr_decode_post_op_attr(p, &fattr);
>  		/* In fact, a post_op_fh3: */
>  		if (*p++) {
> -			p = xdr_decode_fhandle(p, &entry->fh);
> -			/* Ugh -- server reply was truncated */
> -			if (p == NULL) {
> -				dprintk("NFS: FH truncated\n");
> -				*entry = old;
> -				return ERR_PTR(-EAGAIN);
> -			}
> -		} else {
> -			/* If we don't get a file handle, the attrs
> -			 * aren't worth a lot. */
> -			entry->fattr.valid = 0;
> +			struct nfs_fh fh;
> +			p = xdr_decode_fhandle(p, &fh);
>  		}
>  	}
>  
> diff -ruN linux-2.4.23-pre7/fs/nfs/write.c linux-2.4.23-rc1/fs/nfs/write.c
> --- linux-2.4.23-pre7/fs/nfs/write.c	2003-08-25 13:44:43.000000000 +0200
> +++ linux-2.4.23-rc1/fs/nfs/write.c	2003-11-12 11:07:48.000000000 +0100
> @@ -225,8 +225,19 @@
>  	struct inode *inode = page->mapping->host;
>  	unsigned long end_index;
>  	unsigned offset = PAGE_CACHE_SIZE;
> +	int inode_referenced = 0;
>  	int err;
>  
> +	/*
> +	 * Note: We need to ensure that we have a reference to the inode
> +	 *       if we are to do asynchronous writes. If not, waiting
> +	 *       in nfs_wait_on_request() may deadlock with clear_inode().
> +	 *
> +	 *       If igrab() fails here, then it is in any case safe to
> +	 *       call nfs_wb_page(), since there will be no pending writes.
> +	 */
> +	if (igrab(inode) != 0)
> +		inode_referenced = 1;
>  	end_index = inode->i_size >> PAGE_CACHE_SHIFT;
>  
>  	/* Ensure we've flushed out any previous writes */
> @@ -244,7 +255,8 @@
>  		goto out;
>  do_it:
>  	lock_kernel();
> -	if (NFS_SERVER(inode)->wsize >= PAGE_CACHE_SIZE && !IS_SYNC(inode)) {
> +	if (NFS_SERVER(inode)->wsize >= PAGE_CACHE_SIZE && !IS_SYNC(inode) &&
> +			inode_referenced) {
>  		err = nfs_writepage_async(NULL, inode, page, 0, offset);
>  		if (err >= 0)
>  			err = 0;
> @@ -256,7 +268,9 @@
>  	unlock_kernel();
>  out:
>  	UnlockPage(page);
> -	return err; 
> +	if (inode_referenced)
> +		iput(inode);
> +	return err;
>  }
>  
>  /*
> 
> -- 
> J.A. Magallon <jamagallon()able!es>     \                 Software is like sex:
> werewolf!able!es                         \           It's better when it's free
> Mandrake Linux release 10.0 (Cooker) for i586
> Linux 2.4.23-rc1-jam1 (gcc 3.3.1 (Mandrake Linux 9.2 3.3.1-4mdk))

-- 
| G r e g  L o u i s         | gpg public key: 0x400B1AA86D9E3E64 |
|  http://www.bgl.nu/~glouis |   (on my website or any keyserver) |
|  http://wecanstopspam.org in signatures helps fight junk email. |