logfs: destroy the reserved inodes while unmounting

We were assuming that the evict_inode() would never be called on
reserved inodes. However, (after the commit 8e22c1a4e logfs: get rid
of magical inodes) while unmounting the file system, in put_super, we
call iput() on all of the reserved inodes.

The following simple test used to cause a kernel panic on LogFS:

1. Mount a LogFS file system on /mnt

2. Create a file
   $ touch /mnt/a

3. Try to unmount the FS
   $ umount /mnt

The simple fix would be to drop the assumption and properly destroy
the reserved inodes.

Signed-off-by: Prasad Joshi <prasadjoshi.linux@gmail.com>
logfs: initialize the number of iovecs in bio

This fixes the following crash when a LogFS file system, created on a
encrypted LVM volume, was mounted

[  526.548034] BUG: unable to handle kernel NULL pointer dereference at
[  526.550106] IP: [<ffffffff8131ecab>] memcpy+0xb/0x120
[  526.551008] PGD bd60067 PUD 1778d067 PMD 0
[  526.551783] Oops: 0000 [#1] SMP

<d>Pid: 2043, comm: mount
<d>RIP: 0010:[<ffffffff8131ecab>]  [<ffffffff8131ecab>] memcpy+0xb/0x120
Call Trace:
	kcryptd_io_read+0xdb/0x100
	crypt_map+0xfd/0x190
	__map_bio+0x48/0x150
	__split_and_process_bio+0x51b/0x630
	dm_request+0x138/0x230
	generic_make_request+0xca/0x100
	submit_bio+0x87/0x110
	sync_request+0xdd/0x120 [logfs]
	bdev_readpage+0x2e/0x70 [logfs]
	do_read_cache_page+0x82/0x180
	logfs_mount+0x2ad/0x770 [logfs]
	mount_fs+0x47/0x1c0
	vfs_kern_mount+0x72/0x110
	do_kern_mount+0x54/0x110
	do_mount+0x520/0x7f0
	sys_mount+0x90/0xe0

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=42292
Reported-by: Witold Baryluk <baryluk@smp.if.uj.edu.pl>
Signed-off-by: Prasad Joshi <prasadjoshi.linux@gmail.com>
logfs: create a pagecache page if it is not present

While writing the partial journal entries we assumed that the page
associated with the journal would always in locatable. This incorrect
assumption resulted in the following BUG

kernel BUG at /home/benixon/WD_SMR/kernels/linux-3.3.7-logfs/fs/logfs/journal.c:569!
EIP is at logfs_write_area+0xb6/0x109 [logfs]
EAX: 00000000 EBX: 00000000 ECX: ef6efea4 EDX: 00000000
ESI: 001b9000 EDI: f009e000 EBP: c3c13f14 ESP: c3c13ef0
DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068
Process sync (pid: 1799, ti=c3c12000 task=f07825b0 task.ti=c3c12000)
Stack:
01001000 c3c13f26 781b9000 00000000 f009e000 f7286000 f1f83400 f8445071
f1f83400 c3c13f30 f8445ae9 c3c13f20 0000100a 000ee000 f009e000 00000001
c3c13f5c f8445d17 c05eb0ee 00000000 f1f83400 ef718000 f009e25c ea9c3d80
Call Trace:
[<f8445071>] ? account_shadow+0x16d/0x16d [logfs]
[<f8445ae9>] logfs_write_je+0x2a/0x44 [logfs]
[<f8445d17>] logfs_write_anchor+0x114/0x228 [logfs]
[<c05eb0ee>] ? empty+0x5/0x5
[<f8444522>] logfs_sync_fs+0x1e/0x31 [logfs]
[<c051be66>] __sync_filesystem+0x5d/0x6f
[<c051be8d>] sync_one_sb+0x15/0x17
[<c04ff8b0>] iterate_supers+0x59/0x9a
[<c051be78>] ? __sync_filesystem+0x6f/0x6f
[<c051befc>] sys_sync+0x29/0x4f
[<c084285f>] sysenter_do_call+0x12/0x28
EIP: [<f8445127>] logfs_write_area+0xb6/0x109 [logfs] SS:ESP 0068:c3c13ef0
---[ end trace ef6e9ef52601a945 ]---

The fix is to create the pagecache page if it is not locatable.

Reported-and-tested-by: Benixon Dhas <Benixon.Dhas@wdc.com>
Signed-off-by: Prasad Joshi <prasadjoshi.linux@gmail.com>
logfs: maintain the ordering of meta-inode destruction

LogFS does not use a specialized area to maintain the inodes. The
inodes information is kept in a specialized file called inode file.
Similarly, the segment information is kept in a segment file. Since
the segment file also has an inode which is kept in the inode file,
the inode for segment file must be evicted before the inode for inode
file. The change fixes the following BUG during unmount

Pid: 2057, comm: umount Not tainted 3.5.0-rc6+ #25 Bochs Bochs
RIP: 0010:[<ffffffffa005c5f2>]  [<ffffffffa005c5f2>] move_page_to_btree+0x32/0x1f0 [logfs]
Process umount (pid: 2057, threadinfo ...)
Call Trace:
[<ffffffff8112adca>] ? find_get_pages+0x2a/0x180
[<ffffffffa00549f5>] logfs_invalidatepage+0x85/0x90 [logfs]
[<ffffffff81136c51>] truncate_inode_page+0xb1/0xd0
[<ffffffff81136dcf>] truncate_inode_pages_range+0x15f/0x490
[<ffffffff81558549>] ? printk+0x78/0x7a
[<ffffffff81137185>] truncate_inode_pages+0x15/0x20
[<ffffffffa005b7fc>] logfs_evict_inode+0x6c/0x190 [logfs]
[<ffffffff8155c75b>] ? _raw_spin_unlock+0x2b/0x40
[<ffffffff8119e3d7>] evict+0xa7/0x1b0
[<ffffffff8119ea6e>] dispose_list+0x3e/0x60
[<ffffffff8119f1c4>] evict_inodes+0xf4/0x110
[<ffffffff81185b53>] generic_shutdown_super+0x53/0xf0
[<ffffffffa005d8f2>] logfs_kill_sb+0x52/0xf0 [logfs]
[<ffffffff81185ec5>] deactivate_locked_super+0x45/0x80
[<ffffffff81186a4a>] deactivate_super+0x4a/0x70
[<ffffffff811a228e>] mntput_no_expire+0xde/0x140
[<ffffffff811a30ff>] sys_umount+0x6f/0x3a0
[<ffffffff8155d8e9>] system_call_fastpath+0x16/0x1b
---[ end trace 45f7752082cefafd ]---

Signed-off-by: Prasad Joshi <prasadjoshi.linux@gmail.com>
logfs: query block device for number of pages to send with bio

The block device driver puts a limit on maximum number of pages that
can be sent with the bio. Not all block devices can handle
BIO_MAX_PAGES number of pages in bio. Specifically the virtio-blk
diriver limits it to 126. When the LogFS file system was excersized in
KVM, the following bug from do_virtblk_request() was observed

static void do_virtblk_request(struct request_queue *q)
{
	....
	....
	while ((req = blk_peek_request(q)) != NULL) {
		BUG_ON(req->nr_phys_segments + 2 > vblk->sg_elems);
		....
		....
	}
	....
}

The patch fixes the problem by querring the maximum number of pages in
bio allowed from block device driver and then using those many pages
during submit_bio.

Signed-off-by: Prasad Joshi <prasadjoshi.linux@gmail.com>
[PARISC] Redefine ATOMIC_INIT and ATOMIC64_INIT to drop the casts

The following build error occured during a parisc build with
swap-over-NFS patches applied.

net/core/sock.c:274:36: error: initializer element is not constant
net/core/sock.c:274:36: error: (near initialization for 'memalloc_socks')
net/core/sock.c:274:36: error: initializer element is not constant

Dave Anglin says:
> Here is the line in sock.i:
>
> struct static_key memalloc_socks = ((struct static_key) { .enabled =
> ((atomic_t) { (0) }) });

The above line contains two compound literals.  It also uses a designated
initializer to initialize the field enabled.  A compound literal is not a
constant expression.

The location of the above statement isn't fully clear, but if a compound
literal occurs outside the body of a function, the initializer list must
consist of constant expressions.

Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Mel Gorman <mgorman@suse.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
crypto: hifn_795x - fix 64bit division and undefined __divdi3 on 32bit archs

Commit feb7b7ab928afa97a79a9c424e4e0691f49d63be changed NSEC_PER_SEC to 64-bit
constant, which causes "DIV_ROUND_UP(NSEC_PER_SEC, dev->pk_clk_freq)" to
generate __divdi3 call on 32-bit archs. Fix this by changing DIV_ROUND_UP to
DIV_ROUND_UP_ULL.

Signed-off-by: Jussi Kivilinna <jussi.kivilinna@mbnet.fi>
Acked-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
block: reorganize rounding of max_discard_sectors

Mostly a preparation for the next patch.

In principle this fixes an infinite loop if max_discard_sectors < granularity,
but that really shouldn't happen.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Tested-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
block: split discard into aligned requests

When a disk has large discard_granularity and small max_discard_sectors,
discards are not split with optimal alignment.  In the limit case of
discard_granularity == max_discard_sectors, no request could be aligned
correctly, so in fact you might end up with no discarded logical blocks
at all.

Another example that helps showing the condition in the patch is with
discard_granularity == 64, max_discard_sectors == 128.  A request that is
submitted for 256 sectors 2..257 will be split in two: 2..129, 130..257.
However, only 2 aligned blocks out of 3 are included in the request;
128..191 may be left intact and not discarded.  With this patch, the
first request will be truncated to ensure good alignment of what's left,
and the split will be 2..127, 128..255, 256..257.  The patch will also
take into account the discard_alignment.

At most one extra request will be introduced, because the first request
will be reduced by at most granularity-1 sectors, and granularity
must be less than max_discard_sectors.  Subsequent requests will run
on round_down(max_discard_sectors, granularity) sectors, as in the
current code.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Tested-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
fs/block-dev.c:fix performance regression in O_DIRECT writes to md block devices

For regular file, write operaion used blk_plug function.But for block
file,write operation did not use blk_plug.
This patch is also for write-cache mode for block-device.

Signed-off-by: Jianpeng Ma <majianpeng@gmail.com>
Reviewed-by: NeilBrown <neilb@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
nfs: tear down caches in nfs_init_writepagecache when allocation fails

...and ensure that we tear down the nfs_commit_data cache too when
unloading the module.

Cc: Bryan Schumaker <bjschuma@netapp.com>
Cc: stable@vger.kernel.org
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
pnfs: defer release of pages in layoutget

we have encountered a bug whereby reading a lot of files (copying
fedora's /bin) from a pNFS mount and hitting Ctrl+C in the middle caused
a general protection fault in xdr_shrink_bufhead. this function is
called when decoding the response from LAYOUTGET. the decoding is done
by a worker thread, and the caller of LAYOUTGET waits for the worker
thread to complete.

hitting Ctrl+C caused the synchronous wait to end and the next thing the
caller does is to free the pages, so when the worker thread calls
xdr_shrink_bufhead, the pages are gone. therefore, the cleanup of these
pages has been moved to nfs4_layoutget_release.

Signed-off-by: Idan Kedar <idank@tonian.com>
Signed-off-by: Benny Halevy <bhalevy@tonian.com>
Cc: stable@vger.kernel.org
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
pnfs: nfs4_proc_layoutget returns void

since the only user of nfs4_proc_layoutget is send_layoutget, which
ignores its return value, there is no reason to return any value.

Signed-off-by: Idan Kedar <idank@tonian.com>
Signed-off-by: Benny Halevy <bhalevy@tonian.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
NFS41: add pg_layout_private to nfs_pageio_descriptor

To allow layout driver to pass private information around
pg_init/pg_doio.

Signed-off-by: Peng Tao <tao.peng@emc.com>
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
block: Introduce __blk_segment_map_sg() helper

Split the mapping code in blk_rq_map_sg() to a helper
__blk_segment_map_sg(), so that other mapping function, e.g.
blk_bio_map_sg(), can share the code.

Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Tejun Heo <tj@kernel.org>
Cc: Shaohua Li <shli@kernel.org>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: kvm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: virtualization@lists.linux-foundation.org
Suggested-by: Jens Axboe <axboe@kernel.dk>
Suggested-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Asias He <asias@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
block: Add blk_bio_map_sg() helper

Add a helper to map a bio to a scatterlist, modelled after
blk_rq_map_sg.

This helper is useful for any driver that wants to create
a scatterlist from its ->make_request_fn method.

Changes in v2:
 - Use __blk_segment_map_sg to avoid duplicated code
 - Add cocbook style function comment

Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Tejun Heo <tj@kernel.org>
Cc: Shaohua Li <shli@kernel.org>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: kvm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: virtualization@lists.linux-foundation.org
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Minchan Kim <minchan.kim@gmail.com>
Signed-off-by: Asias He <asias@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
pnfs-obj: Better IO pattern in case of unaligned offset

Depending on layout and ARCH, ORE has some limits on max IO sizes
which is communicated on (what else) ore_layout->max_io_length,
which is always stripe aligned.
This was considered as the pg_test boundary for splitting and starting
a new IO.

But in the case of a long IO where the start offset is not aligned
what would happen is that both end of IO[N] and start of IO[N+1]
would be unaligned, causing each IO boundary parity unit to be
calculated and written twice.

So what we do in this patch is split the very start of an unaligned
IO, up to a stripe boundary, and then next IO's can continue fully
aligned til the end.

We might be sacrificing the case where the full unaligned IO would
fit within a single max_io_length, but the sacrifice is well worth
the elimination of double calculation and parity units IO.
Actually the sacrificing is marginal and is almost unmeasurable.

TODO:
	If we know the total expected linear segment that will
	be received, at pg_init, we could use that information
	in many places:
	1. blocks-layout get_layout write segment size
	2. Better mds-threshold
	3. In above situation for a better clean split

	I will do this in future submission.

Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
block: Don't use static to define "void *p" in show_partition_start()

I met a odd prblem:read /proc/partitions may return zero.

I wrote a file test.c:
int main()
{
	char buff[4096];
	int ret;
	int fd;
	printf("pid=%d\n",getpid());
	while (1) {
		fd = open("/proc/partitions", O_RDONLY);
		if (fd < 0) {
			printf("open error %s\n", strerror(errno));
			return 0;
		}
		ret = read(fd, buff, 4096);
		if (ret <= 0)
			printf("ret=%d, %s, %ld\n", ret,
				strerror(errno), lseek(fd,0,SEEK_CUR));
		close(fd);
	}
	exit(0);
}

You can reproduce by:
1:while true;do cat /proc/partitions > /dev/null ;done
2:./test

I reviewed the code and found:

>> static void *show_partition_start(struct seq_file *seqf, loff_t *pos)
>> {
>> 	static void *p;
>>
>> 	p = disk_seqf_start(seqf, pos);
>> 	if (!IS_ERR_OR_NULL(p) && !*pos)
>> 		seq_puts(seqf, "major minor  #blocks  name\n\n");
>> 	return p;
>> }
		test								cat /proc/partitions
	p = disk_seqf_start()(Not NULL)
									p = disk_seqf_start()(NULL because pos)
	if (!IS_ERR_OR_NULL(p) && !*pos)

Signed-off-by: Jianpeng Ma <majianpeng@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
[PARISC] fix personality flag check in copy_thread()

Directly comparing task_struct->personality against PER_* is not fully
correct, as it doesn't take flags potentially stored in top three bytes
into account.

Analogically, directly forcefully setting personality to PER_LINUX32 or
PER_LINUX discards any flags stored in the top three bytes.

Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
powerpc/fsl-pci: Only scan PCI bus if configured as a host

We change fsl_add_bridge to return -ENODEV if the controller is working in
agent mode. Then check the return value of fsl_add_bridge to guarantee
that only successfully added host bus will be scanned.

Signed-off-by: Jia Hongtao <B38951@freescale.com>
Signed-off-by: Li Yang <leoli@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>