NFS: NFSoRDMA Client Side Changes

These patches include several bugfixes and cleanups for the NFSoRDMA client.
This includes bugfixes for NFS v4.1, proper RDMA_ERROR handling, and fixes
from the recent workqueue swicchover.  These patches also switch xprtrdma to
use the new CQ API
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

* tag 'nfs-rdma-4.6-1' of git://git.linux-nfs.org/projects/anna/nfs-rdma: (787 commits)
  xprtrdma: Use new CQ API for RPC-over-RDMA client send CQs
  xprtrdma: Use an anonymous union in struct rpcrdma_mw
  xprtrdma: Use new CQ API for RPC-over-RDMA client receive CQs
  xprtrdma: Serialize credit accounting again
  xprtrdma: Properly handle RDMA_ERROR replies
  rpcrdma: Add RPCRDMA_HDRLEN_ERR
  xprtrdma: Do not wait if ib_post_send() fails
  xprtrdma: Segment head and tail XDR buffers on page boundaries
  xprtrdma: Clean up dprintk format string containing a newline
  xprtrdma: Clean up physical_op_map()
  xprtrdma: Clean up unused RPCRDMA_INLINE_PAD_THRESH macro

I hit the following oops out of the blue while testing with flexfiles:

BUG: unable to handle kernel NULL pointer dereference at 00000000000000e8
IP: [<ffffffffa048f6b8>] nfs4_ff_find_or_create_ds_client+0x48/0x50 [nfs_layout_flexfiles]
PGD 44031067 PUD 5062d067 PMD 0
Oops: 0000 [#1] SMP
Modules linked in: nfsv3 nfs_layout_flexfiles tun rpcsec_gss_krb5 nfsv4 dns_resolver nfs fscache dcdbas nfsd auth_rpcgss nfs_acl lockd grace sunrpc ip6t_rpfilter ip6t_REJECT nf_reject_ipv6 xt_conntrack ebtable_nat ebtable_broute bridge stp llc ebtable_filter ebtables ip6table_nat nf_conntrack_ipv6 nf_defrag_ipv6 nf_nat_ipv6 ip6table_mangle ip6table_security ip6table_raw ip6table_filter ip6_tables iptable_nat nf_conntrack_ipv4 nf_defrag_ipv4 nf_nat_ipv4 nf_nat nf_conntrack iptable_mangle iptable_security iptable_raw bonding ipmi_devintf ipmi_msghandler snd_hda_codec_generic virtio_balloon ppdev snd_hda_intel snd_hda_controller snd_hda_codec iosf_mbi crct10dif_pclmul crc32_pclmul ghash_clmulni_intel snd_hda_core parport_pc snd_hwdep parport snd_seq snd_seq_device snd_pcm snd_timer acpi_cpufreq
 snd soundcore i2c_piix4 xfs libcrc32c joydev virtio_net virtio_console qxl drm_kms_helper ttm crc32c_intel drm virtio_pci serio_raw ata_generic virtio_ring virtio pata_acpi
CPU: 0 PID: 19138 Comm: test5 Not tainted 4.1.9-100.pd.90.el7.x86_64 #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.8.2-20150714_191134- 04/01/2014
task: ffff88007b70cf00 ti: ffff88004cc44000 task.ti: ffff88004cc44000
RIP: 0010:[<ffffffffa048f6b8>]  [<ffffffffa048f6b8>] nfs4_ff_find_or_create_ds_client+0x48/0x50 [nfs_layout_flexfiles]
RSP: 0018:ffff88004cc47890  EFLAGS: 00010246
RAX: 0000000000000003 RBX: ffff880050932300 RCX: ffff88006978f488
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff88003e0e8540
RBP: ffff88004cc47908 R08: 0000000000000000 R09: 0000000000000000
R10: ffff88007ff8c758 R11: 0000000000000005 R12: ffff88003e0e8540
R13: 0000000000000000 R14: ffff88006978f488 R15: ffff88004431cc80
FS:  00007fea40c7c740(0000) GS:ffff88007fc00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000000000e8 CR3: 0000000044318000 CR4: 00000000000406f0
Stack:
 ffffffffa048c934 ffff880050932310 0000000100000001 ffff88006978f510
 ffff88006978f3c8 ffff88003e56cd90 ffff88004cc479d0 00000020a052aff0
 000000000004b000 ffff88004cc47908 ffff880050932300 ffff88004cc479d0
Call Trace:
 [<ffffffffa048c934>] ? ff_layout_write_pagelist+0x64/0x220 [nfs_layout_flexfiles]
 [<ffffffffa057a3bf>] pnfs_generic_pg_writepages+0xaf/0x1b0 [nfsv4]
 [<ffffffffa051ab57>] nfs_pageio_doio+0x27/0x60 [nfs]
 [<ffffffffa051bfe4>] nfs_pageio_complete_mirror+0x54/0xa0 [nfs]
 [<ffffffffa051c7ad>] nfs_pageio_complete+0x2d/0x90 [nfs]
 [<ffffffffa052032d>] nfs_writepage_locked+0x8d/0xe0 [nfs]
 [<ffffffff811e4630>] ? page_referenced_one+0x1a0/0x1a0
 [<ffffffffa05210e7>] nfs_wb_single_page+0xf7/0x190 [nfs]
 [<ffffffffa05108d1>] nfs_launder_page+0x41/0x90 [nfs]
 [<ffffffff811b8930>] invalidate_inode_pages2_range+0x340/0x3a0
 [<ffffffff811b89a7>] invalidate_inode_pages2+0x17/0x20
 [<ffffffffa0513e1e>] nfs_release+0x9e/0xb0 [nfs]
 [<ffffffffa050fa1d>] nfs_file_release+0x3d/0x60 [nfs]
 [<ffffffff8122481c>] __fput+0xdc/0x1e0
 [<ffffffff8122496e>] ____fput+0xe/0x10
 [<ffffffff810bde67>] task_work_run+0xa7/0xe0
 [<ffffffff810af735>] get_signal+0x565/0x600
 [<ffffffff811a9815>] ? __filemap_fdatawrite_range+0x65/0x90
 [<ffffffff810144a7>] do_signal+0x37/0x730
 [<ffffffffa0569921>] ? nfs4_file_fsync+0x81/0x150 [nfsv4]
 [<ffffffff81254dbb>] ? vfs_fsync_range+0x3b/0xb0
 [<ffffffff811446a6>] ? __audit_syscall_exit+0x1e6/0x280
 [<ffffffff81014bff>] do_notify_resume+0x5f/0xa0
 [<ffffffff8178ec3c>] int_signal+0x12/0x17
Code: 48 8b 40 70 8b 00 83 f8 03 74 20 83 f8 04 75 13 55 48 89 ce 48 89 d7 48 89 e5 e8 14 0f 0e 00 5d c3 66 90 0f 0b 66 0f 1f 44 00 00 <48> 8b 82 e8 00 00 00 c3 66 66 66 66 90 55 48 89 e5 41 57 41 56
RIP  [<ffffffffa048f6b8>] nfs4_ff_find_or_create_ds_client+0x48/0x50 [nfs_layout_flexfiles]
 RSP <ffff88004cc47890>
CR2: 00000000000000e8

When the DS connection attempt fails, nfs4_ff_layout_prepare_ds marks it
for the error but then just returns the ds as if it were usable. The
comments though say:

  /* Upon return, either ds is connected, or ds is NULL */

Ensure that we set the return pointer to NULL in the event that the
connection attempt fails.
Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>

Just call inode_dio_wait directly instead of through a pointless wrapper.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>

The only difference to nfs_file_fsync is the call to pnfs_sync_inode.  But
pnfs_sync_inode is just an inline that calls a pNFS layout driver method
if CONFIG_PNFS is designed, and thus can be called just fine from the core
NFS module.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>

Calling ib_poll_cq() to sort through WCs during a completion is a
common pattern amongst RDMA consumers. Since commit 14d3a3b2
("IB: add a proper completion queue abstraction"), WC sorting can
be handled by the IB core.

By converting to this new API, xprtrdma is made a better neighbor to
other RDMA consumers, as it allows the core to schedule the delivery
of completions more fairly amongst all active consumers.

Because each ib_cqe carries a pointer to a completion method, the
core can now post its own operations on a consumer's QP, and handle
the completions itself, without changes to the consumer.

Send completions were previously handled entirely in the completion
upcall handler (ie, deferring to a process context is unneeded).
Thus IB_POLL_SOFTIRQ is a direct replacement for the current
xprtrdma send code path.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Devesh Sharma <devesh.sharma@broadcom.com>
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

Clean up: Make code more readable.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Devesh Sharma <devesh.sharma@broadcom.com>
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

Calling ib_poll_cq() to sort through WCs during a completion is a
common pattern amongst RDMA consumers. Since commit 14d3a3b2
("IB: add a proper completion queue abstraction"), WC sorting can
be handled by the IB core.

By converting to this new API, xprtrdma is made a better neighbor to
other RDMA consumers, as it allows the core to schedule the delivery
of completions more fairly amongst all active consumers.

Because each ib_cqe carries a pointer to a completion method, the
core can now post its own operations on a consumer's QP, and handle
the completions itself, without changes to the consumer.

xprtrdma's reply processing is already handled in a work queue, but
there is some initial order-dependent processing that is done in the
soft IRQ context before a work item is scheduled.

IB_POLL_SOFTIRQ is a direct replacement for the current xprtrdma
receive code path.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Devesh Sharma <devesh.sharma@broadcom.com>
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

Commit fe97b47c ("xprtrdma: Use workqueue to process RPC/RDMA
replies") replaced the reply tasklet with a workqueue that allows
RPC replies to be processed in parallel. Thus the credit values in
RPC-over-RDMA replies can be applied in a different order than in
which the server sent them.

To fix this, revert commit eba8ff66 ("xprtrdma: Move credit
update to RPC reply handler"). Reverting is done by hand to
accommodate code changes that have occurred since then.

Fixes: fe97b47c ("xprtrdma: Use workqueue to process . . .")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

These are shorter than RPCRDMA_HDRLEN_MIN, and they need to
complete the waiting RPC.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

Error headers are shorter than either RDMA_MSG or RDMA_NOMSG.

Since HDRLEN_MIN is already used in several other places that would
be annoying to change, add RPCRDMA_HDRLEN_ERR for the one or two
spots where the shorter length is needed.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Devesh Sharma <devesh.sharma@broadcom.com>
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

If ib_post_send() in ro_unmap_sync() fails, the WRs have not been
posted, no completions will fire, and wait_for_completion() will
wait forever. Skip the wait in that case.

To ensure the MRs are invalid, disconnect.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

A single memory allocation is used for the pair of buffers wherein
the RPC client builds an RPC call message and decodes its matching
reply. These buffers are sized based on the maximum possible size
of the RPC call and reply messages for the operation in progress.

This means that as the call buffer increases in size, the start of
the reply buffer is pushed farther into the memory allocation.

RPC requests are growing in size. It used to be that both the call
and reply buffers fit inside a single page.

But these days, thanks to NFSv4 (and especially security labels in
NFSv4.2) the maximum call and reply sizes are large. NFSv4.0 OPEN,
for example, now requires a 6KB allocation for a pair of call and
reply buffers, and NFSv4 LOOKUP is not far behind.

As the maximum size of a call increases, the reply buffer is pushed
far enough into the buffer's memory allocation that a page boundary
can appear in the middle of it.

When the maximum possible reply size is larger than the client's
RDMA receive buffers (currently 1KB), the client has to register a
Reply chunk for the server to RDMA Write the reply into.

The logic in rpcrdma_convert_iovs() assumes that xdr_buf head and
tail buffers would always be contained on a single page. It supplies
just one segment for the head and one for the tail.

FMR, for example, registers up to a page boundary (only a portion of
the reply buffer in the OPEN case above). But without additional
segments, it doesn't register the rest of the buffer.

When the server tries to write the OPEN reply, the RDMA Write fails
with a remote access error since the client registered only part of
the Reply chunk.

rpcrdma_convert_iovs() must split the XDR buffer into multiple
segments, each of which are guaranteed not to contain a page
boundary. That way fmr_op_map is given the proper number of segments
to register the whole reply buffer.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Devesh Sharma <devesh.sharma@broadcom.com>
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

physical_op_unmap{_sync} don't use mr_nsegs, so don't bother to set
it in physical_op_map.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

Fixes: b3221d6a ('xprtrdma: Remove logic that constructs...')
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

Pull perf fixes from Thomas Gleixner:
 "A rather largish series of 12 patches addressing a maze of race
  conditions in the perf core code from Peter Zijlstra"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf: Robustify task_function_call()
  perf: Fix scaling vs. perf_install_in_context()
  perf: Fix scaling vs. perf_event_enable()
  perf: Fix scaling vs. perf_event_enable_on_exec()
  perf: Fix ctx time tracking by introducing EVENT_TIME
  perf: Cure event->pending_disable race
  perf: Fix race between event install and jump_labels
  perf: Fix cloning
  perf: Only update context time when active
  perf: Allow perf_release() with !event->ctx
  perf: Do not double free
  perf: Close install vs. exit race

Pull x86 fixes from Thomas Gleixner:
 "This update contains:

   - Hopefully the last ASM CLAC fixups

   - A fix for the Quark family related to the IMR lock which makes
     kexec work again

   - A off-by-one fix in the MPX code.  Ironic, isn't it?

   - A fix for X86_PAE which addresses once more an unsigned long vs
     phys_addr_t hickup"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mpx: Fix off-by-one comparison with nr_registers
  x86/mm: Fix slow_virt_to_phys() for X86_PAE again
  x86/entry/compat: Add missing CLAC to entry_INT80_32
  x86/entry/32: Add an ASM_CLAC to entry_SYSENTER_32
  x86/platform/intel/quark: Change the kernel's IMR lock bit to false

Pull scheduler fixlet from Thomas Gleixner:
 "A trivial printk typo fix"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/deadline: Fix trivial typo in printk() message

Pull irq fixes from Thomas Gleixner:
 "Four small fixes for irqchip drivers:

   - Add missing low level irq handler initialization on mxs, so
     interrupts can acutally be delivered

   - Add a missing barrier to the GIC driver

   - Two fixes for the GIC-V3-ITS driver, addressing a double EOI write
     and a cache flush beyond the actual region"

* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  irqchip/gic-v3: Add missing barrier to 32bit version of gic_read_iar()
  irqchip/mxs: Add missing set_handle_irq()
  irqchip/gicv3-its: Avoid cache flush beyond ITS_BASERn memory size
  irqchip/gic-v3-its: Fix double ICC_EOIR write for LPI in EOImode==1

Pull staging/android fix from Greg KH:
 "Here is one patch, for the android binder driver, to resolve a
  reported problem.  Turns out it has been around for a while (since
  3.15), so it is good to finally get it resolved.

  It has been in linux-next for a while with no reported issues"

* tag 'staging-4.5-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging:
  drivers: android: correct the size of struct binder_uintptr_t for BC_DEAD_BINDER_DONE

Pull USB fixes from Greg KH:
 "Here are a few USB fixes for 4.5-rc6

  They fix a reported bug for some USB 3 devices by reverting the recent
  patch, a MAINTAINERS change for some drivers, some new device ids, and
  of course, the usual bunch of USB gadget driver fixes.

  All have been in linux-next for a while with no reported issues"

* tag 'usb-4.5-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
  MAINTAINERS: drop OMAP USB and MUSB maintainership
  usb: musb: fix DMA for host mode
  usb: phy: msm: Trigger USB state detection work in DRD mode
  usb: gadget: net2280: fix endpoint max packet for super speed connections
  usb: gadget: gadgetfs: unregister gadget only if it got successfully registered
  usb: gadget: remove driver from pending list on probe error
  Revert "usb: hub: do not clear BOS field during reset device"
  usb: chipidea: fix return value check in ci_hdrc_pci_probe()
  usb: chipidea: error on overflow for port_test_write
  USB: option: add "4G LTE usb-modem U901"
  USB: cp210x: add IDs for GE B650V3 and B850V3 boards
  USB: option: add support for SIM7100E
  usb: musb: Fix DMA desired mode for Mentor DMA engine
  usb: gadget: fsl_qe_udc: fix IS_ERR_VALUE usage
  usb: dwc2: USB_DWC2 should depend on HAS_DMA
  usb: dwc2: host: fix the data toggle error in full speed descriptor dma
  usb: dwc2: host: fix logical omissions in dwc2_process_non_isoc_desc
  usb: dwc3: Fix assignment of EP transfer resources
  usb: dwc2: Add extra delay when forcing dr_mode

Pull vfs fixes from Al Viro.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  do_last(): ELOOP failure exit should be done after leaving RCU mode
  should_follow_link(): validate ->d_seq after having decided to follow
  namei: ->d_inode of a pinned dentry is stable only for positives
  do_last(): don't let a bogus return value from ->open() et.al. to confuse us
  fs: return -EOPNOTSUPP if clone is not supported
  hpfs: don't truncate the file when delete fails

Pull ARM SoC fixes from Olof Johansson:
 "We didn't have a batch last week, so this one is slightly larger.

  None of them are scary though, a handful of fixes for small DT pieces,
  replacing properties with newer conventions.

  Highlights:
   - N900 fix for setting system revision
   - onenand init fix to avoid filesystem corruption
   - Clock fix for audio on Beaglebone-x15
   - Fixes on shmobile to deal with CONFIG_DEBUG_RODATA (default y in 4.6)

  + misc smaller stuff"

* tag 'armsoc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc:
  MAINTAINERS: Extend info, add wiki and ml for meson arch
  MAINTAINERS: alpine: add a new maintainer and update the entry
  ARM: at91/dt: fix typo in sama5d2 pinmux descriptions
  ARM: OMAP2+: Fix onenand initialization to avoid filesystem corruption
  Revert "regulator: tps65217: remove tps65217.dtsi file"
  ARM: shmobile: Remove shmobile_boot_arg
  ARM: shmobile: Move shmobile_smp_{mpidr, fn, arg}[] from .text to .bss
  ARM: shmobile: r8a7779: Remove remainings of removed SCU boot setup code
  ARM: shmobile: Move shmobile_scu_base from .text to .bss
  ARM: OMAP2+: Fix omap_device for module reload on PM runtime forbid
  ARM: OMAP2+: Improve omap_device error for driver writers
  ARM: DTS: am57xx-beagle-x15: Select SYS_CLK2 for audio clocks
  ARM: dts: am335x/am57xx: replace gpio-key,wakeup with wakeup-source property
  ARM: OMAP2+: Set system_rev from ATAGS for n900
  ARM: dts: orion5x: fix the missing mtd flash on linkstation lswtgl
  ARM: dts: kirkwood: use unique machine name for ds112
  ARM: dts: imx6: remove bogus interrupt-parent from CAAM node

... or we risk seeing a bogus value of d_is_symlink() there.

Cc: stable@vger.kernel.org # v4.2+
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

... otherwise d_is_symlink() above might have nothing to do with
the inode value we've got.

Cc: stable@vger.kernel.org # v4.2+
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

both do_last() and walk_component() risk picking a NULL inode out
of dentry about to become positive, *then* checking its flags and
seeing that it's not negative anymore and using (already stale by
then) value they'd fetched earlier.  Usually ends up oopsing soon
after that...

Cc: stable@vger.kernel.org # v3.13+
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

... into returning a positive to path_openat(), which would interpret that
as "symlink had been encountered" and proceed to corrupt memory, etc.
It can only happen due to a bug in some ->open() instance or in some LSM
hook, etc., so we report any such event *and* make sure it doesn't trick
us into further unpleasantness.

Cc: stable@vger.kernel.org # v3.6+, at least
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

-EBADF is a rather confusing error if an operations is not supported,
and nfsd gets rather upset about it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

The delete opration can allocate additional space on the HPFS filesystem
due to btree split. The HPFS driver checks in advance if there is
available space, so that it won't corrupt the btree if we run out of space
during splitting.

If there is not enough available space, the HPFS driver attempted to
truncate the file, but this results in a deadlock since the commit
7dd29d8d ("HPFS: Introduce a global mutex
and lock it on every callback from VFS").

This patch removes the code that tries to truncate the file and -ENOSPC is
returned instead. If the user hits -ENOSPC on delete, he should try to
delete other files (that are stored in a leaf btree node), so that the
delete operation will make some space for deleting the file stored in
non-leaf btree node.
Reported-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Mikulas Patocka <mikulas@artax.karlin.mff.cuni.cz>
Cc: stable@vger.kernel.org	# 2.6.39+
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Merge fixes from Andrew Morton:
 "10 fixes"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  dax: move writeback calls into the filesystems
  dax: give DAX clearing code correct bdev
  ext4: online defrag not supported with DAX
  ext2, ext4: only set S_DAX for regular inodes
  block: disable block device DAX by default
  ocfs2: unlock inode if deleting inode from orphan fails
  mm: ASLR: use get_random_long()
  drivers: char: random: add get_random_long()
  mm: numa: quickly fail allocations for NUMA balancing on full nodes
  mm: thp: fix SMP race condition between THP page fault and MADV_DONTNEED

Pull ext2/4 DAX fix from Ted Ts'o:
 "This fixes a file system corruption bug with DAX"

* tag 'tags/ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  ext2, ext4: fix issue with missing journal entry in ext4_dax_mkwrite()

Pull PCI fixes from Bjorn Helgaas:
 "Enumeration:
    Revert x86 pcibios_alloc_irq() to fix regression (Bjorn Helgaas)

  Marvell MVEBU host bridge driver:
    Restrict build to 32-bit ARM (Thierry Reding)"

* tag 'pci-v4.5-fixes-3' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci:
  PCI: mvebu: Restrict build to 32-bit ARM
  Revert "PCI, x86: Implement pcibios_alloc_irq() and pcibios_free_irq()"
  Revert "PCI: Add helpers to manage pci_dev->irq and pci_dev->irq_managed"
  Revert "x86/PCI: Don't alloc pcibios-irq when MSI is enabled"

As it is currently written ext4_dax_mkwrite() assumes that the call into
__dax_mkwrite() will not have to do a block allocation so it doesn't create
a journal entry.  For a read that creates a zero page to cover a hole
followed by a write that actually allocates storage this is incorrect.  The
ext4_dax_mkwrite() -> __dax_mkwrite() -> __dax_fault() path calls
get_blocks() to allocate storage.

Fix this by having the ->page_mkwrite fault handler call ext4_dax_fault()
as this function already has all the logic needed to allocate a journal
entry and call __dax_fault().

Also update the ext2 fault handlers in this same way to remove duplicate
code and keep the logic between ext2 and ext4 the same.
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

Pull clk fix from Stephen Boyd:
 "One small fix to keep OMAP platforms working across a suspend/resume
  cycle"

* tag 'clk-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux:
  clk: ti: omap3+: dpll: use non-locking version of clk_get_rate

Previously calls to dax_writeback_mapping_range() for all DAX filesystems
(ext2, ext4 & xfs) were centralized in filemap_write_and_wait_range().

dax_writeback_mapping_range() needs a struct block_device, and it used
to get that from inode->i_sb->s_bdev.  This is correct for normal inodes
mounted on ext2, ext4 and XFS filesystems, but is incorrect for DAX raw
block devices and for XFS real-time files.

Instead, call dax_writeback_mapping_range() directly from the filesystem
->writepages function so that it can supply us with a valid block
device.  This also fixes DAX code to properly flush caches in response
to sync(2).
Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Cc: Al Viro <viro@ftp.linux.org.uk>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Jens Axboe <axboe@fb.com>
Cc: Matthew Wilcox <matthew.r.wilcox@intel.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

dax_clear_blocks() needs a valid struct block_device and previously it
was using inode->i_sb->s_bdev in all cases.  This is correct for normal
inodes on mounted ext2, ext4 and XFS filesystems, but is incorrect for
DAX raw block devices and for XFS real-time devices.

Instead, rename dax_clear_blocks() to dax_clear_sectors(), and change
its arguments to take a bdev and a sector instead of an inode and a
block.  This better reflects what the function does, and it allows the
filesystem and raw block device code to pass in an appropriate struct
block_device.
Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Suggested-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Al Viro <viro@ftp.linux.org.uk>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Jens Axboe <axboe@fb.com>
Cc: Matthew Wilcox <matthew.r.wilcox@intel.com>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Online defrag operations for ext4 are hard coded to use the page cache.
See ext4_ioctl() -> ext4_move_extents() -> move_extent_per_page()

When combined with DAX I/O, which circumvents the page cache, this can
result in data corruption.  This was observed with xfstests ext4/307 and
ext4/308.

Fix this by only allowing online defrag for non-DAX files.
Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Al Viro <viro@ftp.linux.org.uk>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Jens Axboe <axboe@fb.com>
Cc: Matthew Wilcox <matthew.r.wilcox@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

When S_DAX is set on an inode we assume that if there are pages attached
to the mapping (mapping->nrpages != 0), those pages are clean zero pages
that were used to service reads from holes.  Any dirty data associated
with the inode should be in the form of DAX exceptional entries
(mapping->nrexceptional) that is written back via
dax_writeback_mapping_range().

With the current code, though, this isn't always true.  For example,
ext2 and ext4 directory inodes can have S_DAX set, but have their dirty
data stored as dirty page cache entries.  For these types of inodes,
having S_DAX set doesn't really make sense since their I/O doesn't
actually happen through the DAX code path.

Instead, only allow S_DAX to be set for regular inodes for ext2 and
ext4.  This allows us to have strict DAX vs non-DAX paths in the
writeback code.
Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Al Viro <viro@ftp.linux.org.uk>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Jens Axboe <axboe@fb.com>
Cc: Matthew Wilcox <matthew.r.wilcox@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The recent *sync enabling discovered that we are inserting into the
block_device pagecache counter to the expectations of the dirty data
tracking for dax mappings.  This can lead to data corruption.

We want to support DAX for block devices eventually, but it requires
wider changes to properly manage the pagecache.

   dump_stack+0x85/0xc2
   dax_writeback_mapping_range+0x60/0xe0
   blkdev_writepages+0x3f/0x50
   do_writepages+0x21/0x30
   __filemap_fdatawrite_range+0xc6/0x100
   filemap_write_and_wait+0x4a/0xa0
   set_blocksize+0x70/0xd0
   sb_set_blocksize+0x1d/0x50
   ext4_fill_super+0x75b/0x3360
   mount_bdev+0x180/0x1b0
   ext4_mount+0x15/0x20
   mount_fs+0x38/0x170

Mark the support broken so its disabled by default, but otherwise still
available for testing.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Reported-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Suggested-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Jens Axboe <axboe@fb.com>
Cc: Matthew Wilcox <matthew.r.wilcox@intel.com>
Cc: Al Viro <viro@ftp.linux.org.uk>
Cc: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>