[pnfs] pnfs/gfs2 stubs

[david m. richter]

> Ok, tried it out. It goes kablooie in
> 
> print_ds_list
> print_stripe_devs
> device_destroy
> nfs4_pnfs_item_get
> ...
> 
> (sorry, had to copy by hand).
> 
> Any ideas what I might be hitting?
> 
> Unfortunately, it crashes my system hard, and doesn't sync fs
> so /var/log/messages doesn't have much of interest even though I enabled
> nfs_debug and nfsd_debug.
> 
> Frank

	lessee, yeah i have that crash in my logs.  in my case, i think it 
was because the IP address of the DS sent back by GETDEVICEINFO was 
incorrect (ops_export.c:gfs2_get_device_info()).  does the following look 
familiar?  i'll send you a patch with dean's /proc interface for that on 
monday.

 nfs: server dragonwell not responding, timed out
 nfs_create_rpc_client: cannot create RPC client. Error = -5
 <-- nfs4_init_client() = xerror -5
 --> nfs_put_client({1})
 --> nfs_free_client(4)
 <-- nfs_free_client()
 <-- nfs4_set_client() = xerror -5
 nfs4_pnfs_ds_create Returns -5
 decode_and_add_ds nfs4_pnfs_ds_create returned -5
 decode_and_add_ds returned NULL
 device_destroy: dev_id=00000000 00000001
 dev_list:
         stripe_index 0
         num_ds 1
 BUG: unable to handle kernel NULL pointer dereference at 0000000000000010
 IP: [<ffffffff883340aa>] :nfslayoutdriver:print_ds_list+0x4a/0xc0
 PGD 3fbfe067 PUD 3a0bb067 PMD 0
 Oops: 0000 [1]
 CPU 0
 Modules linked in: nfslayoutdriver nfs lock_nolock gfs2 cpufreq_ondemand 
powernow_k8 freq_table nfsd lockd nfs_acl auth_rpcgss exportfs sunrpc 
snd_intel8x0 s nd_ac97_codec ac97_bus snd_seq_oss snd_seq_midi_
event snd_seq snd_seq_device snd_pcm_oss snd_mixer_oss snd_pcm psmouse 
snd_timer snd soundcore usb_storage snd_page_alloc fan thermal button 
processor sg pata_ amd sata_nv ata_generic libata dock sd_mod scsi
_mod uhci_hcd ohci_hcd ehci_hcd usbcore [last unloaded: scsi_wait_scan]
 Pid: 2176, comm: mount.nfs4 Not tainted 2.6.25-rc8-gfs2-pnfs #7
 RIP: 0010:[<ffffffff883340aa>]  [<ffffffff883340aa>] :nfslayoutdriver:print_ds_list+0x4a/0xc0
 RSP: 0018:ffff81003a2136a8  EFLAGS: 00010246
 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
 RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffffffff883355d2
 RBP: ffff81003a2136c8 R08: 0000000000000001 R09: ffffffff80226659
 R10: ffff81003a213488 R11: 0000000000000000 R12: 0000000000000000
 R13: ffff81003486cdf8 R14: ffff81003e4596c0 R15: ffff81003e4596c0
 FS:  00007f03eccda6f0(0000) GS:ffffffff80689000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
 CR2: 0000000000000010 CR3: 000000003a8a6000 CR4: 00000000000006e0
 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
 Process mount.nfs4 (pid: 2176, threadinfo ffff81003a212000, task ffff81003a8b6540)
 Stack:  ffff81003a2136c8 ffff81003486cdf8 0000000000000001 ffff81003e4596c0
  ffff81003a2136f8 ffffffff88334158 ffff81003a2136e8 ffff81003486cd88
  00000000fffffffb 0000000000000000 ffff81003a213758 ffffffff8833428e
 Call Trace:
  [<ffffffff88334158>] :nfslayoutdriver:print_stripe_devs+0x38/0x80
  [<ffffffff8833428e>] :nfslayoutdriver:device_destroy+0x3e/0x170
  [<ffffffff883345dd>] :nfslayoutdriver:nfs4_pnfs_device_item_get+0x21d/0xb80
  [<ffffffff88335148>] :nfslayoutdriver:process_deviceid_list+0x58/0xe0
  [<ffffffff88333bda>] :nfslayoutdriver:filelayout_initialize_mountpoint+0x11a/0x150
  [<ffffffff88308eba>] :nfs:set_pnfs_layoutdriver+0x9a/0x130
  [<ffffffff882de3a2>] :nfs:nfs4_init_pnfs+0x32/0x50
  [<ffffffff882dfb16>] :nfs:nfs4_get_sb+0x436/0x600
  [<ffffffff8027f308>] vfs_kern_mount+0x58/0xc0
  [<ffffffff8027f3de>] do_kern_mount+0x4e/0x100
  [<ffffffff802968e9>] do_new_mount+0x89/0xb0
  [<ffffffff80296acc>] do_mount+0x1bc/0x1f0
  [<ffffffff80294a58>] ? copy_mount_options+0x108/0x170
  [<ffffffff802949a2>] ? copy_mount_options+0x52/0x170
  [<ffffffff80296b8f>] sys_mount+0x8f/0xe0
  [<ffffffff804f02bc>] ? lockdep_sys_exit_thunk+0x35/0x67
  [<ffffffff8020b31b>] system_call_after_swapgs+0x7b/0x80


	d
	.