Oleg Drokin 176d1b9643 staging/lustre/llite: Don't set page writeback on non-dirty page
New writeback changes in 4.2-RC1 have exposed that we incorrectly
set page_writeback on a page that is being written synchronously,
which aside from this new crash (dereference of NULL inode->i_wb
from set_page_writeback) likely threw off some related page
statistics in the past.

 BUG: unable to handle kernel NULL pointer dereference at 0000000000000138
 IP: [<ffffffff8140d90a>] __percpu_counter_add+0x1a/0x80
 PGD 0
 Oops: 0000 [#1] SMP DEBUG_PAGEALLOC
 Modules linked in: osc(C) lmv(C) fld(C) mgc(C) lustre(C) mdc(C) fid(C) lov(C) ksocklnd(C) ptlrpc(C) obdclass(C) lnet(C) libcfs(C) loop sha512_generic crc32 rpcsec_gss_krb5 microcode joydev i2c_piix4 acpi_cpufreq pcspkr nfsd syscopyarea sysfillrect sysimgblt drm_kms_helper ttm drm serio_raw virtio_blk [last unloaded: libcfs]
 CPU: 0 PID: 13328 Comm: cvs Tainted: G         C      4.2.0-rc1-vm-nfs+ #30
 Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
 task: ffff8800cc98a400 ti: ffff8801157e8000 task.ti: ffff8801157e8000
 RIP: 0010:[<ffffffff8140d90a>]  [<ffffffff8140d90a>] __percpu_counter_add+0x1a/0x80
 RSP: 0018:ffff8801157eb698  EFLAGS: 00010086
 RAX: 0000000000000003 RBX: ffffea0002b91cc0 RCX: 000000000000001a
 RDX: 0000000000000020 RSI: 0000000000000001 RDI: 00000000000000e8
 RBP: ffff8801157eb6b8 R08: 0000000000000001 R09: 0000000000000000
 R10: 0000000000000000 R11: 0000000000000000 R12: 00000000000000e8
 R13: 0000000000000001 R14: ffff8800673587a8 R15: ffff8800673589b0
 FS:  00007f6718b89800(0000) GS:ffff88011f400000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 0000000000000138 CR3: 000000009d51c000 CR4: 00000000000007f0
 Stack:
  ffffffff811919e2 ffffea0002b91cc0 ffff880067358998 ffff880119419800
  ffff8801157eb718 ffffffff81191a58 ffff8801157eb788 0000000000000282
  ffff8800ce5ce920 0000000000000000 ffff8800a525af80 ffff880053f68f10
 Call Trace:
  [<ffffffff811919e2>] ? __test_set_page_writeback+0x72/0x240
  [<ffffffff81191a58>] __test_set_page_writeback+0xe8/0x240
  [<ffffffffa04e7a13>] vvp_page_prep_write+0x33/0xb0 [lustre]
  [<ffffffffa028ad87>] cl_page_invoke+0x57/0x90 [obdclass]
  [<ffffffffa028cc8d>] cl_page_prep+0x2d/0x180 [obdclass]
  [<ffffffffa0545d84>] osc_io_submit+0x134/0x4a0 [osc]
  [<ffffffffa02933a3>] cl_io_submit_rw+0x53/0xb0 [obdclass]
  [<ffffffffa0483635>] lov_io_submit+0x3a5/0x570 [lov]
  [<ffffffff810cb7bb>] ? lockdep_init_map+0x5b/0x6d0
  [<ffffffffa02933a3>] cl_io_submit_rw+0x53/0xb0 [obdclass]
  [<ffffffffa029428d>] cl_io_submit_sync+0xed/0x1c0 [obdclass]
  [<ffffffffa04e881d>] vvp_page_sync_io.isra.15+0x4d/0x100 [lustre]
  [<ffffffffa028dd2f>] ? cl_page_clip+0xff/0x130 [obdclass]
  [<ffffffffa04e9f38>] vvp_io_commit_write+0x448/0x500 [lustre]
  [<ffffffffa02939fa>] cl_io_commit_write+0x9a/0x130 [obdclass]
  [<ffffffffa04cb222>] ll_commit_write+0xc2/0x230 [lustre]
  [<ffffffffa04dbdaa>] ll_write_end+0x2a/0x50 [lustre]
  [<ffffffff811851ba>] generic_perform_write+0xfa/0x1b0
  [<ffffffff8121fd2e>] ? dentry_needs_remove_privs.part.16+0x1e/0x30
  [<ffffffff811877d0>] __generic_file_write_iter+0x190/0x1f0
  [<ffffffff8118791a>] generic_file_write_iter+0xea/0x1e0
  [<ffffffffa04e8dd0>] vvp_io_write_start+0xa0/0x1e0 [lustre]
  [<ffffffffa0292469>] cl_io_start+0x49/0x80 [obdclass]
  [<ffffffffa0294803>] cl_io_loop+0x73/0xd0 [obdclass]
  [<ffffffffa04b4ebf>] ll_file_io_generic+0x45f/0x4b0 [lustre]
  [<ffffffffa04b504c>] ll_file_write_iter+0x6c/0xc0 [lustre]
  [<ffffffff8120330a>] __vfs_write+0xaa/0xe0
  [<ffffffff81203969>] vfs_write+0xa9/0x190
  [<ffffffff812046c9>] SyS_write+0x49/0xa0
  [<ffffffff81796572>] entry_SYSCALL_64_fastpath+0x16/0x7a
 Code: 5b 41 5c 41 5d 41 5e 5d c3 0f 1f 84 00 00 00 00 00 55 48 89 e5 41 55 41 54 53 49 89 fc 49 89 f5 48 83 ec 08 65 ff 05 8e d1 bf 7e <48> 8b 47 50 48 63 ca 65 8b 18 48 63 db 48 01 f3 48 39 cb 7d 0a

Signed-off-by: Jinshan Xiong <jinshan.xiong@intel.com>
Signed-off-by: Oleg Drokin <oleg.drokin@intel.com>
Reviewed-on: http://review.whamcloud.com/15610
Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-6854
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-07-31 16:03:50 -07:00
..
2015-05-08 09:23:58 +02:00

Lustre Parallel Filesystem Client
=================================

The Lustre file system is an open-source, parallel file system
that supports many requirements of leadership class HPC simulation
environments.
Born from from a research project at Carnegie Mellon University,
the Lustre file system is a widely-used option in HPC.
The Lustre file system provides a POSIX compliant file system interface,
can scale to thousands of clients, petabytes of storage and
hundreds of gigabytes per second of I/O bandwidth.

Unlike shared disk storage cluster filesystems (e.g. OCFS2, GFS, GPFS),
Lustre has independent Metadata and Data servers that clients can access
in parallel to maximize performance.

In order to use Lustre client you will need to download lustre client
tools from
https://downloads.hpdd.intel.com/public/lustre/latest-feature-release/
the package name is lustre-client.

You will need to install and configure your Lustre servers separately.

Mount Syntax
============
After you installed the lustre-client tools including mount.lustre binary
you can mount your Lustre filesystem with:

mount -t lustre mgs:/fsname mnt

where mgs is the host name or ip address of your Lustre MGS(management service)
fsname is the name of the filesystem you would like to mount.


Mount Options
=============

  noflock
	Disable posix file locking (Applications trying to use
	the functionality will get ENOSYS)

  localflock
	Enable local flock support, using only client-local flock
	(faster, for applications that require flock but do not run
	 on multiple nodes).

  flock
	Enable cluster-global posix file locking coherent across all
	client nodes.

  user_xattr, nouser_xattr
	Support "user." extended attributes (or not)

  user_fid2path, nouser_fid2path
	Enable FID to path translation by regular users (or not)

  checksum, nochecksum
	Verify data consistency on the wire and in memory as it passes
	between the layers (or not).

  lruresize, nolruresize
	Allow lock LRU to be controlled by memory pressure on the server
	(or only 100 (default, controlled by lru_size proc parameter) locks
	 per CPU per server on this client).

  lazystatfs, nolazystatfs
	Do not block in statfs() if some of the servers are down.

  32bitapi
	Shrink inode numbers to fit into 32 bits. This is necessary
	if you plan to reexport Lustre filesystem from this client via
	NFSv4.

  verbose, noverbose
	Enable mount/umount console messages (or not)

More Information
================
You can get more information at
OpenSFS website: http://lustre.opensfs.org/about/
Intel HPDD wiki: https://wiki.hpdd.intel.com

Out of tree Lustre client and server code is available at:
http://git.whamcloud.com/fs/lustre-release.git

Latest binary packages:
http://lustre.opensfs.org/download-lustre/