Commit Graph

662791 Commits

Author SHA1 Message Date
Dan Williams
cf1e22891b device-dax: kill NR_DEV_DAX
There is no point to ask how many device-dax instances the kernel should
support. Since we are already using a dynamic major number, just allow
the max number of minors by default and be done. This also fixes the
fact that the proposed max for the NR_DEV_DAX range was larger than what
could be supported by alloc_chrdev_region().

Fixes: ba09c01d2f ("dax: convert to the cdev api")
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Tested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-05-09 09:08:22 -07:00
Dan Williams
ef51042472 block, dax: move "select DAX" from BLOCK to FS_DAX
For configurations that do not enable DAX filesystems or drivers, do not
require the DAX core to be built.

Given that the 'direct_access' method has been removed from
'block_device_operations', we can also go ahead and remove the
block-related dax helper functions from fs/block_dev.c to
drivers/dax/super.c. This keeps dax details out of the block layer and
lets the DAX core be built as a module in the FS_DAX=n case.

Filesystems need to include dax.h to call bdev_dax_supported().

Cc: linux-xfs@vger.kernel.org
Cc: Jens Axboe <axboe@kernel.dk>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: "Darrick J. Wong" <darrick.wong@oracle.com>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Reviewed-by: Jan Kara <jack@suse.com>
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-05-08 10:55:27 -07:00
Mike Galbraith
74d71a01ab device-dax: Tell kbuild DEV_DAX_PMEM depends on DEV_DAX
ERROR: "devm_create_dev_dax" [drivers/dax/dax_pmem.ko] undefined!
ERROR: "alloc_dax_region" [drivers/dax/dax_pmem.ko] undefined!
ERROR: "dax_region_put" [drivers/dax/dax_pmem.ko] undefined!

Signed-off-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-05-08 10:54:49 -07:00
Dan Williams
736163671b Merge branch 'for-4.12/dax' into libnvdimm-for-next 2017-05-04 23:38:43 -07:00
Dan Williams
d5483feda8 libnvdimm, pfn: fix 'npfns' vs section alignment
Fix failures to create namespaces due to the vmem_altmap not advertising
enough free space to store the memmap.

 WARNING: CPU: 15 PID: 8022 at arch/x86/mm/init_64.c:656 arch_add_memory+0xde/0xf0
 [..]
 Call Trace:
  dump_stack+0x63/0x83
  __warn+0xcb/0xf0
  warn_slowpath_null+0x1d/0x20
  arch_add_memory+0xde/0xf0
  devm_memremap_pages+0x244/0x440
  pmem_attach_disk+0x37e/0x490 [nd_pmem]
  nd_pmem_probe+0x7e/0xa0 [nd_pmem]
  nvdimm_bus_probe+0x71/0x120 [libnvdimm]
  driver_probe_device+0x2bb/0x460
  bind_store+0x114/0x160
  drv_attr_store+0x25/0x30

In commit 658922e57b "libnvdimm, pfn: fix memmap reservation sizing"
we arranged for the capacity to be allocated, but failed to also update
the 'npfns' parameter. This leads to cases where there is enough
capacity reserved to hold all the allocated sections, but
vmemmap_populate_hugepages() still encounters -ENOMEM from
altmap_alloc_block_buf().

This fix is a stop-gap until we can teach the core memory hotplug
implementation to permit sub-section hotplug.

Cc: <stable@vger.kernel.org>
Fixes: 658922e57b ("libnvdimm, pfn: fix memmap reservation sizing")
Reported-by: Anisha Allada <anisha.allada@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-05-04 19:54:42 -07:00
Dan Williams
9d62ed9651 libnvdimm: handle locked label storage areas
Per the latest version of the "NVDIMM DSM Interface Example" [1], the
label data retrieval routine can report a "locked" status. In this case
all regions associated with that DIMM are disabled until the label area
is unlocked. Provide generic libnvdimm enabling for NVDIMMs with label
data area locking capabilities.

[1]: http://pmem.io/documents/

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-05-04 15:41:39 -07:00
Dan Williams
8f078b38dd libnvdimm: convert NDD_ flags to use bitops, introduce NDD_LOCKED
This is a preparation patch for handling locked nvdimm label regions, a
new concept as introduced by the latest DSM document on pmem.io [1]. A
future patch will leverage nvdimm_set_locked() at DIMM probe time to
flag regions that can not be enabled. There should be no functional
difference resulting from this change.

[1]: http://pmem.io/documents/NVDIMM_DSM_Interface_Example-V1.3.pdf

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-05-04 14:01:24 -07:00
Gerald Schaefer
1ef97fe4f8 brd: fix uninitialized use of brd->dax_dev
commit 1647b9b9 "brd: add dax_operations support" introduced the allocation
and freeing of a dax_device, but the allocated dax_device is not stored
into the brd_device, so brd_del_one() will eventually operate on an
uninitialized brd->dax_dev.

Fix this by storing the allocated dax_device to brd->dax_dev.

Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-05-03 11:30:03 -07:00
Arnd Bergmann
67fd389735 block, dax: use correct format string in bdev_dax_supported
The new message has an incorrect format string, causing a warning in some
configurations:

fs/block_dev.c: In function 'bdev_dax_supported':
fs/block_dev.c:779:5: error: format '%d' expects argument of type 'int', but argument 2 has type 'long int' [-Werror=format=]
     "error: dax access failed (%d)", len);

This changes it to use the correct %ld instead of %d.

Fixes: 2093f2e9df ("block, dax: convert bdev_dax_supported() to dax_direct_access()")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-05-01 13:16:29 -07:00
Dan Williams
565851c972 device-dax: fix sysfs attribute deadlock
Usage of device_lock() for dax_region attributes is unnecessary and
deadlock prone. It's unnecessary because the order of registration /
un-registration guarantees that drvdata is always valid. It's deadlock
prone because it sets up this situation:

 ndctl           D    0  2170   2082 0x00000000
 Call Trace:
  __schedule+0x31f/0x980
  schedule+0x3d/0x90
  schedule_preempt_disabled+0x15/0x20
  __mutex_lock+0x402/0x980
  ? __mutex_lock+0x158/0x980
  ? align_show+0x2b/0x80 [dax]
  ? kernfs_seq_start+0x2f/0x90
  mutex_lock_nested+0x1b/0x20
  align_show+0x2b/0x80 [dax]
  dev_attr_show+0x20/0x50

 ndctl           D    0  2186   2079 0x00000000
 Call Trace:
  __schedule+0x31f/0x980
  schedule+0x3d/0x90
  __kernfs_remove+0x1f6/0x340
  ? kernfs_remove_by_name_ns+0x45/0xa0
  ? remove_wait_queue+0x70/0x70
  kernfs_remove_by_name_ns+0x45/0xa0
  remove_files.isra.1+0x35/0x70
  sysfs_remove_group+0x44/0x90
  sysfs_remove_groups+0x2e/0x50
  dax_region_unregister+0x25/0x40 [dax]
  devm_action_release+0xf/0x20
  release_nodes+0x16d/0x2b0
  devres_release_all+0x3c/0x60
  device_release_driver_internal+0x17d/0x220
  device_release_driver+0x12/0x20
  unbind_store+0x112/0x160

ndctl/2170 is trying to acquire the device_lock() to read an attribute,
and ndctl/2186 is holding the device_lock() while trying to drain all
active attribute readers.

Thanks to Yi Zhang for the reproduction script.

Fixes: d7fe1a67f6 ("dax: add region 'id', 'size', and 'align' attributes")
Cc: <stable@vger.kernel.org>
Reported-by: Yi Zhang <yizhan@redhat.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-05-01 13:14:37 -07:00
Dan Williams
a3e9af95f7 libnvdimm: restore "libnvdimm: band aid btt vs clear poison locking"
This continues the 4.11 status quo of disabling of error clearing from
the BTT I/O path. Toshi found that even though we have eliminated all
the libnvdimm sources of sleeping-while-atomic triggers, we still have
sleeping operations that will occur in the path to send the ACPI DSM to
the DIMM to clear the error:

 BUG: sleeping function called from invalid context at mm/slab.h:432
 in_atomic(): 1, irqs_disabled(): 0, pid: 13353, name: dd
 Call Trace:
  dump_stack+0x86/0xc3
  ___might_sleep+0x17d/0x250
  __might_sleep+0x4a/0x80
  __kmalloc+0x1c0/0x2e0
  acpi_os_allocate_zeroed+0x2d/0x2f
  acpi_evaluate_object+0x59/0x3b1
  acpi_evaluate_dsm+0xbd/0x10c
  acpi_nfit_ctl+0x1ef/0x7c0 [nfit]
  ? nsio_rw_bytes+0x152/0x280
  nvdimm_clear_poison+0x77/0x140
  nsio_rw_bytes+0x18f/0x280
  btt_write_pg+0x1d4/0x3d0 [nd_btt]
  btt_make_request+0x119/0x2d0 [nd_btt]

A solution for tracking and handling media errors natively in the BTT is
needed.

Cc: Jeff Moyer <jmoyer@redhat.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Reported-by: Toshi Kani <toshi.kani@hpe.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-05-01 10:00:02 -07:00
Dan Williams
452bae0aed libnvdimm: fix nvdimm_bus_lock() vs device_lock() ordering
A debug patch to turn the standard device_lock() into something that
lockdep can analyze yielded the following:

 ======================================================
 [ INFO: possible circular locking dependency detected ]
 4.11.0-rc4+ #106 Tainted: G           O
 -------------------------------------------------------
 lt-libndctl/1898 is trying to acquire lock:
  (&dev->nvdimm_mutex/3){+.+.+.}, at: [<ffffffffc023c948>] nd_attach_ndns+0x178/0x1b0 [libnvdimm]

 but task is already holding lock:
  (&nvdimm_bus->reconfig_mutex){+.+.+.}, at: [<ffffffffc022e0b1>] nvdimm_bus_lock+0x21/0x30 [libnvdimm]

 which lock already depends on the new lock.

 the existing dependency chain (in reverse order) is:

 -> #1 (&nvdimm_bus->reconfig_mutex){+.+.+.}:
        lock_acquire+0xf6/0x1f0
        __mutex_lock+0x88/0x980
        mutex_lock_nested+0x1b/0x20
        nvdimm_bus_lock+0x21/0x30 [libnvdimm]
        nvdimm_namespace_capacity+0x1b/0x40 [libnvdimm]
        nvdimm_namespace_common_probe+0x230/0x510 [libnvdimm]
        nd_pmem_probe+0x14/0x180 [nd_pmem]
        nvdimm_bus_probe+0xa9/0x260 [libnvdimm]

 -> #0 (&dev->nvdimm_mutex/3){+.+.+.}:
        __lock_acquire+0x1107/0x1280
        lock_acquire+0xf6/0x1f0
        __mutex_lock+0x88/0x980
        mutex_lock_nested+0x1b/0x20
        nd_attach_ndns+0x178/0x1b0 [libnvdimm]
        nd_namespace_store+0x308/0x3c0 [libnvdimm]
        namespace_store+0x87/0x220 [libnvdimm]

In this case '&dev->nvdimm_mutex/3' mirrors '&dev->mutex'.

Fix this by replacing the use of device_lock() with nvdimm_bus_lock() to protect
nd_{attach,detach}_ndns() operations.

Cc: <stable@vger.kernel.org>
Fixes: 8c2f7e8658 ("libnvdimm: infrastructure for btt devices")
Reported-by: Yi Zhang <yizhan@redhat.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-05-01 08:29:37 -07:00
Dan Williams
23f4984483 libnvdimm: rework region badblocks clearing
Toshi noticed that the new support for a region-level badblocks missed
the case where errors are cleared due to BTT I/O.

An initial attempt to fix this ran into a "sleeping while atomic"
warning due to taking the nvdimm_bus_lock() in the BTT I/O path to
satisfy the locking requirements of __nvdimm_bus_badblocks_clear().
However, that lock is not needed since we are not acting on any data that
is subject to change under that lock. The badblocks instance has its own
internal lock to handle mutations of the error list.

So, in order to make it clear that we are just acting on region devices,
rename __nvdimm_bus_badblocks_clear() to nvdimm_clear_badblocks_regions().
Eliminate the lock and consolidate all support routines for the new
nvdimm_account_cleared_poison() in drivers/nvdimm/bus.c. Finally, to the
opportunity to cleanup to some unnecessary casts, make the calling
convention of nvdimm_clear_badblocks_regions() clearer by replacing struct
resource with the minimal struct clear_badblocks_context, and use the
DEVICE_ATTR macro.

Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Reported-by: Toshi Kani <toshi.kani@hpe.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-04-29 15:24:03 -07:00
Dan Williams
7699a6a36b acpi, nfit: kill ACPI_NFIT_DEBUG
Inevitably when one actually needs to debug a DSM issue it's on a
distribution kernel that has CONFIG_ACPI_NFIT_DEBUG=n. The config symbol
was only there to avoid the compile error due to the missing fallback for
print_hex_dump_debug in the CONFIG_DYNAMIC_DEBUG=n case. That was fixed
with commit cdf17449af "hexdump: do not print debug dumps for
!CONFIG_DEBUG", so the config symbol can just be dropped.

Cc: Joe Perches <joe@perches.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-04-28 16:07:00 -07:00
Toshi Kani
8d13c02906 libnvdimm: fix clear length of nvdimm_forget_poison()
ND_CMD_CLEAR_ERROR command returns 'clear_err.cleared', the length
of error actually cleared, which may be smaller than its requested
'len'.

Change nvdimm_clear_poison() to call nvdimm_forget_poison() with
'clear_err.cleared' when this value is valid.

Cc: <stable@vger.kernel.org>
Fixes: e046114af5 ("libnvdimm: clear the internal poison_list when clearing badblocks")
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Toshi Kani <toshi.kani@hpe.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-04-28 15:56:26 -07:00
Toshi Kani
b2518c78ce libnvdimm, pmem: fix a NULL pointer BUG in nd_pmem_notify
The following BUG was observed when nd_pmem_notify() was called
for a BTT device.  The use of a pmem_device pointer is not valid
with BTT.

 BUG: unable to handle kernel NULL pointer dereference at 0000000000000030
 IP: nd_pmem_notify+0x30/0xf0 [nd_pmem]
 Call Trace:
  nd_device_notify+0x40/0x50
  child_notify+0x10/0x20
  device_for_each_child+0x50/0x90
  nd_region_notify+0x20/0x30
  nd_device_notify+0x40/0x50
  nvdimm_region_notify+0x27/0x30
  acpi_nfit_scrub+0x341/0x590 [nfit]
  process_one_work+0x197/0x450
  worker_thread+0x4e/0x4a0
  kthread+0x109/0x140

Fix nd_pmem_notify() by setting nd_region and badblocks pointers
properly for BTT.

Cc: <stable@vger.kernel.org>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Fixes: 719994660c ("libnvdimm: async notification support")
Signed-off-by: Toshi Kani <toshi.kani@hpe.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-04-28 12:46:47 -07:00
Dan Williams
ab630891ce libnvdimm, region: sysfs trigger for nvdimm_flush()
The nvdimm_flush() mechanism helps to reduce the impact of an ADR
(asynchronous-dimm-refresh) failure. The ADR mechanism handles flushing
platform WPQ (write-pending-queue) buffers when power is removed. The
nvdimm_flush() mechanism performs that same function on-demand.

When a pmem namespace is associated with a block device, an
nvdimm_flush() is triggered with every block-layer REQ_FUA, or REQ_FLUSH
request. These requests are typically associated with filesystem
metadata updates. However, when a namespace is in device-dax mode,
userspace (think database metadata) needs another path to perform the
same flushing. In other words this is not required to make data
persistent, but in the case of metadata it allows for a smaller failure
domain in the unlikely event of an ADR failure.

The new 'deep_flush' attribute is visible when the individual DIMMs
backing a given interleave-set are described by platform firmware. In
ACPI terms this is "NVDIMM Region Mapping Structures" and associated
"Flush Hint Address Structures". Reads return "1" if the region supports
triggering WPQ flushes on all DIMMs. Reads return "0" the flush
operation is a platform nop, and in that case the attribute is
read-only.

Why sysfs and not an ioctl? An ioctl requires establishing a new
ioctl function number space for device-dax. Given that this would be
called on a device-dax fd an application could be forgiven for
accidentally calling this on a filesystem-dax fd. Placing this interface
in libnvdimm sysfs removes that potential for collision with a
filesystem ioctl, and it keeps ioctls out of the generic device-dax
implementation.

Cc: Jeff Moyer <jmoyer@redhat.com>
Cc: Masayoshi Mizuma <m.mizuma@jp.fujitsu.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-04-28 12:46:46 -07:00
Toshi Kani
97681f9b08 libnvdimm: fix phys_addr for nvdimm_clear_poison
nvdimm_clear_poison() expects a physical address, not an offset.
Fix nsio_rw_bytes() to call nvdimm_clear_poison() with a physical
address.

Signed-off-by: Toshi Kani <toshi.kani@hpe.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Reviewed-by: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-04-27 13:51:18 -07:00
Dan Williams
6abccd1bfe x86, dax, pmem: remove indirection around memcpy_from_pmem()
memcpy_from_pmem() maps directly to memcpy_mcsafe(). The wrapper
serves no real benefit aside from affording a more generic function name
than the x86-specific 'mcsafe'. However this would not be the first time
that x86 terminology leaked into the global namespace. For lack of
better name, just use memcpy_mcsafe() directly.

This conversion also catches a place where we should have been using
plain memcpy, acpi_nfit_blk_single_io().

Cc: <x86@kernel.org>
Cc: Jan Kara <jack@suse.cz>
Cc: Jeff Moyer <jmoyer@redhat.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Acked-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-04-25 13:20:46 -07:00
Dan Williams
d4b29fd78e block: remove block_device_operations ->direct_access()
Now that all the producers and consumers of dax interfaces have been
converted to using dax_operations on a dax_device, remove the block
device direct_access enabling.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-04-25 13:20:46 -07:00
Dan Williams
2093f2e9df block, dax: convert bdev_dax_supported() to dax_direct_access()
Kill of the final user of bdev_direct_access() and struct blk_dax_ctl.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-04-25 13:20:46 -07:00
Dan Williams
cccbce6715 filesystem-dax: convert to dax_direct_access()
Now that a dax_device is plumbed through all dax-capable drivers we can
switch from block_device_operations to dax_operations for invoking
->direct_access.

This also lets us kill off some usages of struct blk_dax_ctl on the way
to its eventual removal.

Suggested-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-04-25 13:20:46 -07:00
Dan Williams
a41fe02b6b Revert "block: use DAX for partition table reads"
commit d1a5f2b4d8 ("block: use DAX for partition table reads") was
part of a stalled effort to allow dax mappings of block devices. Since
then the device-dax mechanism has filled the role of dax-mapping static
device ranges.

Now that we are moving ->direct_access() from a block_device operation
to a dax_inode operation we would need block devices to map and carry
their own dax_inode reference.

Unless / until we decide to revive dax mapping of raw block devices
through the dax_inode scheme, there is no need to carry
read_dax_sector(). Its removal in turn allows for the removal of
bdev_direct_access() and should have been included in commit
2237570168 ("block_dev: remove DAX leftovers").

Cc: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-04-25 13:20:46 -07:00
Dan Williams
fa5d932c32 ext2, ext4, xfs: retrieve dax_device for iomap operations
In preparation for converting fs/dax.c to use dax_direct_access()
instead of bdev_direct_access(), add the plumbing to retrieve the
dax_device associated with a given block_device.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-04-25 13:20:46 -07:00
Dan Williams
817bf40265 dm: teach dm-targets to use a dax_device + dax_operations
Arrange for dm to lookup the dax services available from member devices.
Update the dax-capable targets, linear and stripe, to route dax
operations to the underlying device. Changes the target-internal
->direct_access() method to more closely align with the dax_operations
->direct_access() calling convention.

Cc: Toshi Kani <toshi.kani@hpe.com>
Reviewed-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-04-25 13:20:36 -07:00
Dan Williams
bc042fdfbb libnvdimm, region: fix flush hint detection crash
In the case where a dimm does not have any associated flush hints the
ndrd->flush_wpq array may be uninitialized leading to crashes with the
following signature:

 BUG: unable to handle kernel NULL pointer dereference at 0000000000000010
 IP: region_visible+0x10f/0x160 [libnvdimm]

 Call Trace:
  internal_create_group+0xbe/0x2f0
  sysfs_create_groups+0x40/0x80
  device_add+0x2d8/0x650
  nd_async_device_register+0x12/0x40 [libnvdimm]
  async_run_entry_fn+0x39/0x170
  process_one_work+0x212/0x6c0
  ? process_one_work+0x197/0x6c0
  worker_thread+0x4e/0x4a0
  kthread+0x10c/0x140
  ? process_one_work+0x6c0/0x6c0
  ? kthread_create_on_node+0x60/0x60
  ret_from_fork+0x31/0x40

Cc: <stable@vger.kernel.org>
Reviewed-by: Jeff Moyer <jmoyer@redhat.com>
Fixes: f284a4f237 ("libnvdimm: introduce nvdimm_flush() and nvdimm_has_flush()")
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-04-24 16:01:56 -07:00
Dan Williams
f26c5719b2 dm: add dax_device and dax_operations support
Allocate a dax_device to represent the capacity of a device-mapper
instance. Provide a ->direct_access() method via the new dax_operations
indirection that mirrors the functionality of the current direct_access
support via block_device_operations.  Once fs/dax.c has been converted
to use dax_operations the old dm_blk_direct_access() will be removed.

A new helper dm_dax_get_live_target() is introduced to separate some of
the dm-specifics from the direct_access implementation.

This enabling is only for the top-level dm representation to upper
layers. Converting target direct_access implementations is deferred to a
separate patch.

Cc: Toshi Kani <toshi.kani@hpe.com>
Reviewed-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-04-20 11:57:52 -07:00
Dan Williams
b0686260fe dax: introduce dax_direct_access()
Replace bdev_direct_access() with dax_direct_access() that uses
dax_device and dax_operations instead of a block_device and
block_device_operations for dax. Once all consumers of the old api have
been converted bdev_direct_access() will be deleted.

Given that block device partitioning decisions can cause dax page
alignment constraints to be violated this also introduces the
bdev_dax_pgoff() helper. It handles calculating a logical pgoff relative
to the dax_device and also checks for page alignment.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-04-20 11:57:52 -07:00
Dan Williams
d8f07aee3f block: kill bdev_dax_capable()
This is leftover dead code that has since been replaced by
bdev_dax_supported().

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-04-20 11:57:52 -07:00
Dan Williams
7a2765f6e8 dcssblk: add dax_operations support
Setup a dax_dev to have the same lifetime as the dcssblk block device
and add a ->direct_access() method that is equivalent to
dcssblk_direct_access(). Once fs/dax.c has been converted to use
dax_operations the old dcssblk_direct_access() will be removed.

Reported-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Acked-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-04-19 15:14:36 -07:00
Dan Williams
1647b9b959 brd: add dax_operations support
Setup a dax_inode to have the same lifetime as the brd block device and
add a ->direct_access() method that is equivalent to
brd_direct_access(). Once fs/dax.c has been converted to use
dax_operations the old brd_direct_access() will be removed.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-04-19 15:14:36 -07:00
Dan Williams
60fcd55cc2 axon_ram: add dax_operations support
Setup a dax_device to have the same lifetime as the axon_ram block
device and add a ->direct_access() method that is equivalent to
axon_ram_direct_access(). Once fs/dax.c has been converted to use
dax_operations the old axon_ram_direct_access() will be removed.

Reported-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-04-19 15:14:36 -07:00
Dan Williams
c1d6e828a3 pmem: add dax_operations support
Setup a dax_device to have the same lifetime as the pmem block device
and add a ->direct_access() method that is equivalent to
pmem_direct_access(). Once fs/dax.c has been converted to use
dax_operations the old pmem_direct_access() will be removed.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-04-19 15:14:35 -07:00
Dan Williams
6568b08b77 dax: introduce dax_operations
Track a set of dax_operations per dax_device that can be set at
alloc_dax() time. These operations will be used to stop the abuse of
block_device_operations for communicating dax capabilities to
filesystems. It will also be used to replace the "pmem api" and move
pmem-specific cache maintenance, and other dax-driver-specific
filesystem-dax operations, to dax device methods. In particular this
allows us to stop abusing __copy_user_nocache(), via memcpy_to_pmem(),
with a driver specific replacement.

This is a standalone introduction of the operations. Follow on patches
convert each dax-driver and teach fs/dax.c to use ->direct_access() from
dax_operations instead of block_device_operations.

Suggested-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-04-19 15:14:35 -07:00
Dan Williams
7205800541 dax: add a facility to lookup a dax device by 'host' device name
For the current block_device based filesystem-dax path, we need a way
for it to lookup the dax_device associated with a block_device. Add a
'host' property of a dax_device that can be used for this purpose. It is
a free form string, but for a dax_device associated with a block device
it is the bdev name.

This is a stop-gap until filesystems are able to mount on a dax-inode
directly.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-04-19 15:14:31 -07:00
Dan Williams
fbabd829fe acpi, nfit: fix module unload vs workqueue shutdown race
The workqueue may still be running when the devres callbacks start
firing to deallocate an acpi_nfit_desc instance. Stop and flush the
workqueue before letting any other devres de-allocations proceed.

Reported-by: Linda Knippers <linda.knippers@hpe.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-04-18 10:55:37 -07:00
Dan Williams
8b06b884cd tools/testing/nvdimm: fix nfit_test shutdown crash
Keep the nfit_test instances alive until after nfit_test_teardown(), as
we may be doing resource lookups until the final un-registrations have
completed. This fixes crashes of the form.

 BUG: unable to handle kernel NULL pointer dereference at 0000000000000038
 IP: __release_resource+0x12/0x90
 Call Trace:
  remove_resource+0x23/0x40
  __wrap_remove_resource+0x29/0x30 [nfit_test_iomap]
  acpi_nfit_remove_resource+0xe/0x10 [nfit]
  devm_action_release+0xf/0x20
  release_nodes+0x16d/0x2b0
  devres_release_all+0x3c/0x60
  device_release+0x21/0x90
  kobject_release+0x6a/0x170
  kobject_put+0x2f/0x60
  put_device+0x17/0x20
  platform_device_unregister+0x20/0x30
  nfit_test_exit+0x36/0x960 [nfit_test]

Reported-by: Linda Knippers <linda.knippers@hpe.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-04-18 10:26:09 -07:00
Dan Williams
9ccaed4bfd acpi, nfit: limit ->flush_probe() to initialization work
The nvdimm probe flushing mechanism gives userspace a sync point where
it knows all asynchronous driver probe sequences have completed.
However, it need not wait for other asynchronous actions, like
on-demand address-range-scrub. Track the init work separately from other
work in the workqueue, and only flush the former.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-04-17 12:34:17 -07:00
Dan Williams
caa603aae0 acpi, nfit: collate health state flags
Be tolerant of cases where the BIOS provided NFIT does not consistently
set the flags in all NVDIMM Region Mapping structures associated with a
given dimm.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-04-17 12:34:17 -07:00
Dan Williams
1499934dcd acpi, nfit: support "map failed" dimms
Stop requiring dimms be successfully mapped into a
system-physical-address range. For provisioning and hardware remediation
purposes the kernel should account for failed devices in sysfs. If
possible it should still allow management commands to be sent to the
device.

Reported-by: Toshi Kani <toshi.kani@hpe.com>
Tested-by: Toshi Kani <toshi.kani@hpe.com>
Reported-by: Linda Knippers <linda.knippers@hpe.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-04-17 12:34:17 -07:00
Dan Williams
ac40b675c7 tools/testing/nvdimm: test acpi 6.1 health state flags
Add a simulated dimm with an ACPI_NFIT_MEM_MAP_FAILED indication, and
set the ACPI_NFIT_MEM_HEALTH_ENABLED flag on all the dimms where
nfit_test simulates health events, but spread it out over several
redundant memdev entries to test that the nfit driver coalesces all the
flags.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-04-17 12:34:17 -07:00
Dan Williams
ffab9385b3 acpi, nfit: add support for acpi 6.1 dimm state flags
Add support for the ACPI_NFIT_MEM_MAP_FAILED ("map_fail") and
ACPI_NFIT_MEM_HEALTH_ENABLED ("smart_notify") health state flags. The
"map_fail" flag identifies DIMMs that were not mapped into one or more
physical address ranges. The "health_notify" flag indicates whether
platform firmware will send notifications when there is new SMART health
data to consume.

Acked-by: Toshi Kani <toshi.kani@hpe.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-04-14 13:29:44 -07:00
Dan Williams
e88da7998d Revert "libnvdimm: band aid btt vs clear poison locking"
This reverts commit 4aa5615e08 "libnvdimm: band aid btt vs clear
poison locking".

Now that poison list locking has been converted to a spinlock and poison
list entry allocation during i/o has been converted to GFP_NOWAIT,
revert the band-aid that disabled error clearing from btt i/o.

Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-04-14 13:29:01 -07:00
Dave Jiang
b3b454f694 libnvdimm: fix clear poison locking with spinlock and GFP_NOWAIT allocation
The following warning results from holding a lane spinlock,
preempt_disable(), or the btt map spinlock and then trying to take the
reconfig_mutex to walk the poison list and potentially add new entries.

BUG: sleeping function called from invalid context at kernel/locking/mutex.
c:747
in_atomic(): 1, irqs_disabled(): 0, pid: 17159, name: dd
[..]
Call Trace:
dump_stack+0x85/0xc8
___might_sleep+0x184/0x250
__might_sleep+0x4a/0x90
__mutex_lock+0x58/0x9b0
? nvdimm_bus_lock+0x21/0x30 [libnvdimm]
? __nvdimm_bus_badblocks_clear+0x2f/0x60 [libnvdimm]
? acpi_nfit_forget_poison+0x79/0x80 [nfit]
? _raw_spin_unlock+0x27/0x40
mutex_lock_nested+0x1b/0x20
nvdimm_bus_lock+0x21/0x30 [libnvdimm]
nvdimm_forget_poison+0x25/0x50 [libnvdimm]
nvdimm_clear_poison+0x106/0x140 [libnvdimm]
nsio_rw_bytes+0x164/0x270 [libnvdimm]
btt_write_pg+0x1de/0x3e0 [nd_btt]
? blk_queue_enter+0x30/0x290
btt_make_request+0x11a/0x310 [nd_btt]
? blk_queue_enter+0xb7/0x290
? blk_queue_enter+0x30/0x290
generic_make_request+0x118/0x3b0

A spinlock is introduced to protect the poison list. This allows us to not
having to acquire the reconfig_mutex for touching the poison list. The
add_poison() function has been broken out into two helper functions. One to
allocate the poison entry and the other to apppend the entry. This allows us
to unlock the poison_lock in non-I/O path and continue to be able to allocate
the poison entry with GFP_KERNEL. We will use GFP_NOWAIT in the I/O path in
order to satisfy being in atomic context.

Reviewed-by: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-04-13 14:23:51 -07:00
Dan Williams
7b6be8444e dax: refactor dax-fs into a generic provider of 'struct dax_device' instances
We want dax capable drivers to be able to publish a set of dax
operations [1]. However, we do not want to further abuse block_devices
to advertise these operations. Instead we will attach these operations
to a dax device and add a lookup mechanism to go from block device path
to a dax device. A dax capable driver like pmem or brd is responsible
for registering a dax device, alongside a block device, and then a dax
capable filesystem is responsible for retrieving the dax device by path
name if it wants to call dax_operations.

For now, we refactor the dax pseudo-fs to be a generic facility, rather
than an implementation detail, of the device-dax use case. Where a "dax
device" is just an inode + dax infrastructure, and "Device DAX" is a
mapping service layered on top of that base 'struct dax_device'.
"Filesystem DAX" is then a mapping service that layers a filesystem on
top of that same base device. Filesystem DAX is associated with a
block_device for now, but perhaps directly to a dax device in the
future, or for new pmem-only filesystems.

[1]: https://lkml.org/lkml/2017/1/19/880

Suggested-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-04-12 21:59:14 -07:00
Dan Williams
5f0694b300 device-dax: rename 'dax_dev' to 'dev_dax'
In preparation for introducing a struct dax_device type to the kernel
global type namespace, rename dax_dev to dev_dax. A 'dax_device'
instance will be a generic device-driver object for any provider of dax
functionality. A 'dev_dax' object is a device-dax-driver local /
internal instance.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-04-12 21:59:13 -07:00
Oliver O'Halloran
762026203c device-dax: improve fault handler debug output
A couple of minor improvements to the debug output in the fault handlers:

a) Print the region alignment and fault size when we sent a SIGBUS
   because the region alignment is greater than the fault size.
b) Fix the message in the PFN_{DEV|MAP} check.
c) Additionally print the fault size enum value in the huge fault handler.

Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-04-12 21:59:13 -07:00
Pushkar Jambhlekar
54eafcc9e3 device-dax: fix dax_dev_huge_fault() unknown fault size handling
The default case for dax_dev_huge_fault() fault size handling mistakenly
returns when it should unlock. This is not a problem in practice since
the only three possible fault sizes are handled. Going forward, if the
core mm adds a new fault size beyond pte, pmd, or pud device-dax should
abort VM_FAULT_SIGBUS requests not VM_FAULT_FALLBACK since device-dax
guarantees a configured fault granularity for all faults.

Signed-off-by: Pushkar Jambhlekar <pushkar.iit@gmail.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-04-12 21:59:13 -07:00
Dan Williams
bfca9acf1a Merge branch 'for-4.11/libnvdimm' into for-4.12/dax 2017-04-12 21:59:01 -07:00
Dave Jiang
efebc71118 device-dax, tools/testing/nvdimm: enable device-dax with mock resources
Provide a replacement pgoff_to_phys() that translates an nfit_test
resource (allocated by vmalloc()) to a pfn.

Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-04-12 21:56:43 -07:00