Commit Graph

49 Commits

Author SHA1 Message Date
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
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
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
Dave Jiang 006358b35c libnvdimm: add support for clear poison list and badblocks for device dax
Providing mechanism to clear poison list via the ndctl ND_CMD_CLEAR_ERROR
call. We will update the poison list and also the badblocks at region level
if the region is in dax mode or in pmem mode and not active. In other
words we force badblocks to be cleared through write requests if the
address is currently accessed through a block device, otherwise it can
only be done via the ioctl+dsm path.

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
Dan Williams 0beb2012a1 libnvdimm: fix reconfig_mutex, mmap_sem, and jbd2_handle lockdep splat
Holding the reconfig_mutex over a potential userspace fault sets up a
lockdep dependency chain between filesystem-DAX and the libnvdimm ioctl
path. Move the user access outside of the lock.

     [ INFO: possible circular locking dependency detected ]
     4.11.0-rc3+ #13 Tainted: G        W  O
     -------------------------------------------------------
     fallocate/16656 is trying to acquire lock:
      (&nvdimm_bus->reconfig_mutex){+.+.+.}, at: [<ffffffffa00080b1>] nvdimm_bus_lock+0x21/0x30 [libnvdimm]
     but task is already holding lock:
      (jbd2_handle){++++..}, at: [<ffffffff813b4944>] start_this_handle+0x104/0x460

    which lock already depends on the new lock.

    the existing dependency chain (in reverse order) is:

    -> #2 (jbd2_handle){++++..}:
            lock_acquire+0xbd/0x200
            start_this_handle+0x16a/0x460
            jbd2__journal_start+0xe9/0x2d0
            __ext4_journal_start_sb+0x89/0x1c0
            ext4_dirty_inode+0x32/0x70
            __mark_inode_dirty+0x235/0x670
            generic_update_time+0x87/0xd0
            touch_atime+0xa9/0xd0
            ext4_file_mmap+0x90/0xb0
            mmap_region+0x370/0x5b0
            do_mmap+0x415/0x4f0
            vm_mmap_pgoff+0xd7/0x120
            SyS_mmap_pgoff+0x1c5/0x290
            SyS_mmap+0x22/0x30
            entry_SYSCALL_64_fastpath+0x1f/0xc2

    -> #1 (&mm->mmap_sem){++++++}:
            lock_acquire+0xbd/0x200
            __might_fault+0x70/0xa0
            __nd_ioctl+0x683/0x720 [libnvdimm]
            nvdimm_ioctl+0x8b/0xe0 [libnvdimm]
            do_vfs_ioctl+0xa8/0x740
            SyS_ioctl+0x79/0x90
            do_syscall_64+0x6c/0x200
            return_from_SYSCALL_64+0x0/0x7a

    -> #0 (&nvdimm_bus->reconfig_mutex){+.+.+.}:
            __lock_acquire+0x16b6/0x1730
            lock_acquire+0xbd/0x200
            __mutex_lock+0x88/0x9b0
            mutex_lock_nested+0x1b/0x20
            nvdimm_bus_lock+0x21/0x30 [libnvdimm]
            nvdimm_forget_poison+0x25/0x50 [libnvdimm]
            nvdimm_clear_poison+0x106/0x140 [libnvdimm]
            pmem_do_bvec+0x1c2/0x2b0 [nd_pmem]
            pmem_make_request+0xf9/0x270 [nd_pmem]
            generic_make_request+0x118/0x3b0
            submit_bio+0x75/0x150

Cc: <stable@vger.kernel.org>
Fixes: 62232e45f4 ("libnvdimm: control (ioctl) messages for nvdimm_bus and nvdimm devices")
Cc: Dave Jiang <dave.jiang@intel.com>
Reported-by: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-04-10 17:21:45 -07:00
Dan Williams efda1b5d87 acpi, nfit, libnvdimm: fix / harden ars_status output length handling
Given ambiguities in the ACPI 6.1 definition of the "Output (Size)"
field of the ARS (Address Range Scrub) Status command, a firmware
implementation may in practice return 0, 4, or 8 to indicate that there
is no output payload to process.

The specification states "Size of Output Buffer in bytes, including this
field.". However, 'Output Buffer' is also the name of the entire
payload, and earlier in the specification it states "Max Query ARS
Status Output Buffer Size: Maximum size of buffer (including the Status
and Extended Status fields)".

Without this fix if the BIOS happens to return 0 it causes memory
corruption as evidenced by this result from the acpi_nfit_ctl() unit
test.

 ars_status00000000: 00020000 00000000                    ........
 BUG: stack guard page was hit at ffffc90001750000 (stack is ffffc9000174c000..ffffc9000174ffff)
 kernel stack overflow (page fault): 0000 [#1] SMP DEBUG_PAGEALLOC
 task: ffff8803332d2ec0 task.stack: ffffc9000174c000
 RIP: 0010:[<ffffffff814cfe72>]  [<ffffffff814cfe72>] __memcpy+0x12/0x20
 RSP: 0018:ffffc9000174f9a8  EFLAGS: 00010246
 RAX: ffffc9000174fab8 RBX: 0000000000000000 RCX: 000000001fffff56
 RDX: 0000000000000000 RSI: ffff8803231f5a08 RDI: ffffc90001750000
 RBP: ffffc9000174fa88 R08: ffffc9000174fab0 R09: ffff8803231f54b8
 R10: 0000000000000008 R11: 0000000000000001 R12: 0000000000000000
 R13: 0000000000000000 R14: 0000000000000003 R15: ffff8803231f54a0
 FS:  00007f3a611af640(0000) GS:ffff88033ed00000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: ffffc90001750000 CR3: 0000000325b20000 CR4: 00000000000406e0
 Stack:
  ffffffffa00bc60d 0000000000000008 ffffc90000000001 ffffc9000174faac
  0000000000000292 ffffffffa00c24e4 ffffffffa00c2914 0000000000000000
  0000000000000000 ffffffff00000003 ffff880331ae8ad0 0000000800000246
 Call Trace:
  [<ffffffffa00bc60d>] ? acpi_nfit_ctl+0x49d/0x750 [nfit]
  [<ffffffffa01f4fe0>] nfit_test_probe+0x670/0xb1b [nfit_test]

Cc: <stable@vger.kernel.org>
Fixes: 747ffe11b4 ("libnvdimm, tools/testing/nvdimm: fix 'ars_status' output buffer sizing")
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2016-12-06 16:08:10 -08:00
Dan Williams 178d6f4be8 Merge branch 'for-4.9/libnvdimm' into libnvdimm-for-next 2016-10-07 16:46:24 -07:00
Vishal Verma e046114af5 libnvdimm: clear the internal poison_list when clearing badblocks
nvdimm_clear_poison cleared the user-visible badblocks, and sent
commands to the NVDIMM to clear the areas marked as 'poison', but it
neglected to clear the same areas from the internal poison_list which is
used to marshal ARS results before sorting them by namespace. As a
result, once on-demand ARS functionality was added:

37b137f nfit, libnvdimm: allow an ARS scrub to be triggered on demand

A scrub triggered from either sysfs or an MCE was found to be adding
stale entries that had been cleared from gendisk->badblocks, but were
still present in nvdimm_bus->poison_list. Additionally, the stale entries
could be triggered into producing stale disk->badblocks by simply disabling
and re-enabling the namespace or region.

This adds the missing step of clearing poison_list entries when clearing
poison, so that it is always in sync with badblocks.

Fixes: 37b137f ("nfit, libnvdimm: allow an ARS scrub to be triggered on demand")
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2016-09-30 17:03:45 -07:00
Dave Jiang 1e8b8d9619 libnvdimm: allow legacy (e820) pmem region to clear bad blocks
Bad blocks can be injected via /sys/block/pmemN/badblocks. In a situation
where legacy pmem is being used or a pmem region created by using memmap
kernel parameter, the injected bad blocks are not cleared due to
nvdimm_clear_poison() failing from lack of ndctl function pointer. In
this case we need to just return as handled and allow the bad blocks to
be cleared rather than fail.

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>
2016-09-09 17:34:46 -07:00
Linus Torvalds f0c98ebc57 libnvdimm for 4.8
1/ Replace pcommit with ADR / directed-flushing:
    The pcommit instruction, which has not shipped on any product, is
    deprecated. Instead, the requirement is that platforms implement either
    ADR, or provide one or more flush addresses per nvdimm. ADR
    (Asynchronous DRAM Refresh) flushes data in posted write buffers to the
    memory controller on a power-fail event. Flush addresses are defined in
    ACPI 6.x as an NVDIMM Firmware Interface Table (NFIT) sub-structure:
    "Flush Hint Address Structure". A flush hint is an mmio address that
    when written and fenced assures that all previous posted writes
    targeting a given dimm have been flushed to media.
 
 2/ On-demand ARS (address range scrub):
    Linux uses the results of the ACPI ARS commands to track bad blocks
    in pmem devices.  When latent errors are detected we re-scrub the media
    to refresh the bad block list, userspace can also request a re-scrub at
    any time.
 
 3/ Support for the Microsoft DSM (device specific method) command format.
 
 4/ Support for EDK2/OVMF virtual disk device memory ranges.
 
 5/ Various fixes and cleanups across the subsystem.
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Merge tag 'libnvdimm-for-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm

Pull libnvdimm updates from Dan Williams:

 - Replace pcommit with ADR / directed-flushing.

   The pcommit instruction, which has not shipped on any product, is
   deprecated.  Instead, the requirement is that platforms implement
   either ADR, or provide one or more flush addresses per nvdimm.

   ADR (Asynchronous DRAM Refresh) flushes data in posted write buffers
   to the memory controller on a power-fail event.

   Flush addresses are defined in ACPI 6.x as an NVDIMM Firmware
   Interface Table (NFIT) sub-structure: "Flush Hint Address Structure".
   A flush hint is an mmio address that when written and fenced assures
   that all previous posted writes targeting a given dimm have been
   flushed to media.

 - On-demand ARS (address range scrub).

   Linux uses the results of the ACPI ARS commands to track bad blocks
   in pmem devices.  When latent errors are detected we re-scrub the
   media to refresh the bad block list, userspace can also request a
   re-scrub at any time.

 - Support for the Microsoft DSM (device specific method) command
   format.

 - Support for EDK2/OVMF virtual disk device memory ranges.

 - Various fixes and cleanups across the subsystem.

* tag 'libnvdimm-for-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (41 commits)
  libnvdimm-btt: Delete an unnecessary check before the function call "__nd_device_register"
  nfit: do an ARS scrub on hitting a latent media error
  nfit: move to nfit/ sub-directory
  nfit, libnvdimm: allow an ARS scrub to be triggered on demand
  libnvdimm: register nvdimm_bus devices with an nd_bus driver
  pmem: clarify a debug print in pmem_clear_poison
  x86/insn: remove pcommit
  Revert "KVM: x86: add pcommit support"
  nfit, tools/testing/nvdimm/: unify shutdown paths
  libnvdimm: move ->module to struct nvdimm_bus_descriptor
  nfit: cleanup acpi_nfit_init calling convention
  nfit: fix _FIT evaluation memory leak + use after free
  tools/testing/nvdimm: add manufacturing_{date|location} dimm properties
  tools/testing/nvdimm: add virtual ramdisk range
  acpi, nfit: treat virtual ramdisk SPA as pmem region
  pmem: kill __pmem address space
  pmem: kill wmb_pmem()
  libnvdimm, pmem: use nvdimm_flush() for namespace I/O writes
  fs/dax: remove wmb_pmem()
  libnvdimm, pmem: flush posted-write queues on shutdown
  ...
2016-07-28 17:38:16 -07:00
Dan Williams 18515942d6 libnvdimm: register nvdimm_bus devices with an nd_bus driver
A recent effort to add a new nvdimm bus provider attribute highlighted a
race between interrogating nvdimm_bus->nd_desc and nvdimm_bus tear down.
The typical way to handle these races is to take the device_lock() in
the attribute method and validate that the device is still active.  In
order for a device to be 'active' it needs to be associated with a
driver.  So, we create the small boilerplate for a driver and register
nvdimm_bus devices on the 'nvdimm_bus_type' bus.

A result of this change is that ndbusX devices now appear under
/sys/bus/nd/devices.  In fact this makes /sys/class/nd somewhat
redundant, but removing that will need to take a long deprecation period
given its use by ndctl binaries in the field.

This change naturally pulls code from drivers/nvdimm/core.c to
drivers/nvdimm/bus.c, so it is a nice code organization clean-up as
well.

Cc: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2016-07-23 11:06:33 -07:00
Dan Williams bc9775d869 libnvdimm: move ->module to struct nvdimm_bus_descriptor
Let the provider module be explicitly passed in rather than implicitly
assumed by the module that calls nvdimm_bus_register().  This is in
preparation for unifying the nfit and nfit_test driver teardown paths.

Reviewed-by: Lee, Chun-Yi <jlee@suse.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2016-07-21 20:03:19 -07:00
Dan Williams 476f848aae libnvdimm, pmem: flush posted-write queues on shutdown
Commit writes to media on system shutdown or pmem driver unload.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2016-07-12 15:13:48 -07:00
Dan Williams 52c44d93c2 block: remove ->driverfs_dev
Now that all drivers that specify a ->driverfs_dev have been converted
to device_add_disk(), the pointer can be removed from struct gendisk.

Cc: Jens Axboe <axboe@fb.com>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2016-06-27 12:26:08 -07:00
Dan Williams 4258895814 libnvdimm: IS_ERR() usage cleanup
Prompted by commit 287980e49f "remove lots of IS_ERR_VALUE abuses", I
ran make coccicheck against drivers/nvdimm/ and found that:

	if (IS_ERR(x))
		return PTR_ERR(x);
	return 0;

...can be replaced with PTR_ERR_OR_ZERO().

Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2016-06-17 16:23:23 -07:00
Dan Williams 36092ee8ba Merge branch 'for-4.7/dax' into libnvdimm-for-next 2016-05-21 12:33:04 -07:00
Dan Williams 1f716d05f8 Merge branch 'for-4.7/dsm' into libnvdimm-for-next 2016-05-18 10:06:59 -07:00
Dan Williams 2159669f58 Merge branch 'for-4.7/libnvdimm' into libnvdimm-for-next 2016-05-18 10:06:48 -07:00
Dan Williams 6cf9c5babd libnvdimm: stop requiring a driver ->remove() method
The dax_pmem driver was implementing an empty ->remove() method to
satisfy the nvdimm bus driver that unconditionally calls ->remove().
Teach the core bus driver to check if ->remove() is NULL to remove that
requirement.

Reported-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2016-05-18 09:13:13 -07:00
Dan Williams cd03412a51 libnvdimm, dax: introduce device-dax infrastructure
Device DAX is the device-centric analogue of Filesystem DAX
(CONFIG_FS_DAX).  It allows persistent memory ranges to be allocated and
mapped without need of an intervening file system.  This initial
infrastructure arranges for a libnvdimm pfn-device to be represented as
a different device-type so that it can be attached to a driver other
than the pmem driver.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2016-05-09 15:35:42 -07:00
Dan Williams 31eca76ba2 nfit, libnvdimm: limited/whitelisted dimm command marshaling mechanism
There are currently 4 known similar but incompatible definitions of the
command sets that can be sent to an NVDIMM through ACPI.  It is also
clear that future platform generations (ACPI or not) will continue to
revise and extend the DIMM command set as new devices and use cases
arrive.

It is obviously untenable to continue to proliferate divergence
of these command definitions, and to that end a standardization process
has begun to provide for a unified specification.  However, that leaves a
problem about what to do with this first generation where vendors are
already shipping divergence.

The Linux kernel can support these initial diverged platforms without
giving platform-firmware free reign to continue to diverge and compound
kernel maintenance overhead.  The kernel implementation can encourage
standardization in two ways:

1/ Require that any function code that userspace wants to send be
   explicitly white-listed in the implementation.  For ACPI this means
   function codes marked as supported by acpi_check_dsm() may
   only be invoked if they appear in the white-list.  A function must be
   publicly documented before it is added to the white-list.

2/ The above restrictions can be trivially bypassed by using the
   "vendor-specific" payload command.  However, since vendor-specific
   commands are by definition not publicly documented and have the
   potential to corrupt the kernel's view of the dimm state, we provide a
   toggle to disable vendor-specific operations.  Enabling undefined
   behavior is a policy decision that can be made by the platform owner
   and encourages firmware implementations to choose public over
   private command implementations.

Based on an initial patch from Jerry Hoemann
Cc: Jerry Hoemann <jerry.hoemann@hpe.com>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2016-04-28 16:59:06 -07:00
Dan Williams e3654eca70 nfit, libnvdimm: clarify "commands" vs "_DSMs"
Clarify the distinction between "commands", the ioctls userspace calls
to request the kernel take some action on a given dimm device, and
"_DSMs", the actual function numbers used in the firmware interface to
the DIMM.  _DSMs are ACPI specific whereas commands are Linux kernel
generic.

This is in preparation for breaking the 1:1 implicit relationship
between the kernel ioctl number space and the firmware specific function
numbers.

Cc: Jerry Hoemann <jerry.hoemann@hpe.com>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2016-04-28 16:23:16 -07:00
Dan Williams baa51277cf libnvdimm, test: add mock SMART data payload
Provide simulated SMART data to enable the ndctl implementation of SMART
data retrieval and parsing.

The payload is defined here, "Section 4.1 SMART and Health Info
(Function Index 1)":

    http://pmem.io/documents/NVDIMM_DSM_Interface_Example.pdf

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2016-04-11 11:11:14 -07:00
Dan Williams 2112911266 libnvdimm: fix smart data retrieval
It appears that smart data retrieval has been broken the since the
initial implementation.  Fix the payload size to be 128-bytes per the
specification.

Cc: <stable@vger.kernel.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2016-04-07 19:58:44 -07:00
Linus Torvalds de06dbfa78 Merge branch 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm
Pull ARM updates from Russell King:
 "Another mixture of changes this time around:

   - Split XIP linker file from main linker file to make it more
     maintainable, and various XIP fixes, and clean up a resulting
     macro.

   - Decompressor cleanups from Masahiro Yamada

   - Avoid printing an error for a missing L2 cache

   - Remove some duplicated symbols in System.map, and move
     vectors/stubs back into kernel VMA

   - Various low priority fixes from Arnd

   - Updates to allow bus match functions to return negative errno
     values, touching some drivers and the driver core.  Greg has acked
     these changes.

   - Virtualisation platform udpates form Jean-Philippe Brucker.

   - Security enhancements from Kees Cook

   - Rework some Kconfig dependencies and move PSCI idle management code
     out of arch/arm into drivers/firmware/psci.c

   - ARM DMA mapping updates, touching media, acked by Mauro.

   - Fix places in ARM code which should be using virt_to_idmap() so
     that Keystone2 can work.

   - Fix Marvell Tauros2 to work again with non-DT boots.

   - Provide a delay timer for ARM Orion platforms"

* 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm: (45 commits)
  ARM: 8546/1: dma-mapping: refactor to fix coherent+cma+gfp=0
  ARM: 8547/1: dma-mapping: store buffer information
  ARM: 8543/1: decompressor: rename suffix_y to compress-y
  ARM: 8542/1: decompressor: merge piggy.*.S and simplify Makefile
  ARM: 8541/1: decompressor: drop redundant FORCE in Makefile
  ARM: 8540/1: decompressor: use clean-files instead of extra-y to clean files
  ARM: 8539/1: decompressor: drop more unneeded assignments to "targets"
  ARM: 8538/1: decompressor: drop unneeded assignments to "targets"
  ARM: 8532/1: uncompress: mark putc as inline
  ARM: 8531/1: turn init_new_context into an inline function
  ARM: 8530/1: remove VIRT_TO_BUS
  ARM: 8537/1: drop unused DEBUG_RODATA from XIP_KERNEL
  ARM: 8536/1: mm: hide __start_rodata_section_aligned for non-debug builds
  ARM: 8535/1: mm: DEBUG_RODATA makes no sense with XIP_KERNEL
  ARM: 8534/1: virt: fix hyp-stub build for pre-ARMv7 CPUs
  ARM: make the physical-relative calculation more obvious
  ARM: 8512/1: proc-v7.S: Adjust stack address when XIP_KERNEL
  ARM: 8411/1: Add default SPARSEMEM settings
  ARM: 8503/1: clk_register_clkdev: remove format string interface
  ARM: 8529/1: remove 'i' and 'zi' targets
  ...
2016-03-19 16:31:54 -07:00
Dan Williams 59e6473980 libnvdimm, pmem: clear poison on write
If a write is directed at a known bad block perform the following:

1/ write the data

2/ send a clear poison command

3/ invalidate the poison out of the cache hierarchy

Cc: <x86@kernel.org>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Reviewed-by: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2016-03-09 15:15:32 -08:00
Dan Williams d4f323672a nfit, libnvdimm: clear poison command support
Add the boiler-plate for a 'clear error' command based on section
9.20.7.6 "Function Index 4 - Clear Uncorrectable Error" from the ACPI
6.1 specification, and add a reference implementation in nfit_test.

Reviewed-by: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2016-03-05 18:06:14 -08:00
Jerry Hoemann 07accfa9d1 libnvdimm: Fix security issue with DSM IOCTL.
Code attempts to prevent certain IOCTL DSM from being called
when device is opened read only.  This security feature can
be trivially overcome by changing the size portion of the
ioctl_command which isn't used.

Check only the _IOC_NR (i.e. the command).

Cc: <stable@vger.kernel.org>
Signed-off-by: Jerry Hoemann <jerry.hoemann@hpe.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2016-03-05 12:24:06 -08:00
Jerry Hoemann 4dc0e7be88 libnvdimm: Clean-up access mode check.
Change nd_ioctl and nvdimm_ioctl access mode check to use O_RDONLY.

Signed-off-by: Jerry Hoemann <jerry.hoemann@hpe.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2016-03-05 12:24:06 -08:00
Dan Williams 87bf572e19 nfit: disable userspace initiated ars during scrub
While the nfit driver is issuing address range scrub commands and
reaping the results do not permit an ars_start command issued from
userspace.  The scrub thread assumes that all ars completions are for
scrubs initiated by platform firmware at boot, or by the nfit driver.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2016-03-05 12:24:06 -08:00
Dan Williams 719994660c libnvdimm: async notification support
In preparation for asynchronous address range scrub support add an
ability for the pmem driver to dynamically consume address range scrub
results.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2016-03-05 12:24:06 -08:00
Dan Williams aef2533822 libnvdimm, nfit: centralize command status translation
The return value from an 'ndctl_fn' reports the command execution
status, i.e. was the command properly formatted and was it successfully
submitted to the bus provider.  The new 'cmd_rc' parameter allows the bus
provider to communicate command specific results, translated into
common error codes.

Convert the ARS commands to this scheme to:

1/ Consolidate status reporting

2/ Prepare for for expanding ars unit test cases

3/ Make the implementation more generic

Cc: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2016-03-05 12:24:06 -08:00
Dan Williams 4577b06655 nfit: update address range scrub commands to the acpi 6.1 format
The original format of these commands from the "NVDIMM DSM Interface
Example" [1] are superseded by the ACPI 6.1 definition of the "NVDIMM Root
Device _DSMs" [2].

[1]: http://pmem.io/documents/NVDIMM_DSM_Interface_Example.pdf
[2]: http://www.uefi.org/sites/default/files/resources/ACPI_6_1.pdf
     "9.20.7 NVDIMM Root Device _DSMs"

Changes include:
1/ New 'restart' fields in ars_status, unfortunately these are
   implemented in the middle of the existing definition so this change
   is not backwards compatible.  The expectation is that shipping
   platforms will only ever support the ACPI 6.1 definition.

2/ New status values for ars_start ('busy') and ars_status ('overflow').

Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Linda Knippers <linda.knippers@hpe.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2016-02-23 17:17:20 -08:00
Dan Williams 747ffe11b4 libnvdimm, tools/testing/nvdimm: fix 'ars_status' output buffer sizing
Use the output length specified in the command to size the receive
buffer rather than the arbitrary 4K limit.

This bug was hiding the fact that the ndctl implementation of
ndctl_bus_cmd_new_ars_status() was not specifying an output buffer size.

Cc: <stable@vger.kernel.org>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2016-02-19 15:21:52 -08:00
Dan Williams 82ec2ba2b1 ARM: 8522/1: drivers: nvdimm: ensure no negative value gets returned on positive match
This patch ensures that existing bus match callbacks don't return
negative values (which might be interpreted as potential errors in the
future) in case of positive match.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2016-02-16 16:28:50 +00:00
Axel Lin daa1dee405 nvdimm: Fix return value of nvdimm_bus_init() if class_create() fails
Return proper error if class_create() fails.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2015-06-30 14:30:34 -04:00
Dan Williams af834d457d libnvdimm: smatch cleanups in __nd_ioctl
Drop use of access_ok() since we are already using copy_{to|from}_user()
which do their own access_ok().

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2015-06-30 14:10:09 -04:00
Toshi Kani 74ae66c3b1 libnvdimm: Add sysfs numa_node to NVDIMM devices
Add support of sysfs 'numa_node' to I/O-related NVDIMM devices
under /sys/bus/nd/devices, regionN, namespaceN.0, and bttN.x.

An example of numa_node values on a 2-socket system with a single
NVDIMM range on each socket is shown below.
  /sys/bus/nd/devices
  |-- btt0.0/numa_node:0
  |-- btt1.0/numa_node:1
  |-- btt1.1/numa_node:1
  |-- namespace0.0/numa_node:0
  |-- namespace1.0/numa_node:1
  |-- region0/numa_node:0
  |-- region1/numa_node:1

These numa_node files are then linked under the block class of
their device names.
  /sys/class/block/pmem0/device/numa_node:0
  /sys/class/block/pmem1s/device/numa_node:1

This enables numactl(8) to accept 'block:' and 'file:' paths of
pmem and btt devices as shown in the examples below.
  numactl --preferred block:pmem0 --show
  numactl --preferred file:/dev/pmem1s --show

Signed-off-by: Toshi Kani <toshi.kani@hp.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2015-06-26 11:23:38 -04:00
Toshi Kani 41d7a6d637 libnvdimm: Set numa_node to NVDIMM devices
ACPI NFIT table has System Physical Address Range Structure entries that
describe a proximity ID of each range when ACPI_NFIT_PROXIMITY_VALID is
set in the flags.

Change acpi_nfit_register_region() to map a proximity ID to its node ID,
and set it to a new numa_node field of nd_region_desc, which is then
conveyed to the nd_region device.

The device core arranges for btt and namespace devices to inherit their
node from their parent region.

Signed-off-by: Toshi Kani <toshi.kani@hp.com>
[djbw: move set_dev_node() from region.c to bus.c]
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2015-06-26 11:23:38 -04:00
Dan Williams 5813882094 libnvdimm, nfit: handle unarmed dimms, mark namespaces read-only
Upon detection of an unarmed dimm in a region, arrange for descendant
BTT, PMEM, or BLK instances to be read-only.  A dimm is primarily marked
"unarmed" via flags passed by platform firmware (NFIT).

The flags in the NFIT memory device sub-structure indicate the state of
the data on the nvdimm relative to its energy source or last "flush to
persistence".  For the most part there is nothing the driver can do but
advertise the state of these flags in sysfs and emit a message if
firmware indicates that the contents of the device may be corrupted.
However, for the case of ACPI_NFIT_MEM_ARMED, the driver can arrange for
the block devices incorporating that nvdimm to be marked read-only.
This is a safe default as the data is still available and new writes are
held off until the administrator either forces read-write mode, or the
energy source becomes armed.

A 'read_only' attribute is added to REGION devices to allow for
overriding the default read-only policy of all descendant block devices.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2015-06-26 11:23:38 -04:00
Dan Williams 8c2f7e8658 libnvdimm: infrastructure for btt devices
NVDIMM namespaces, in addition to accepting "struct bio" based requests,
also have the capability to perform byte-aligned accesses.  By default
only the bio/block interface is used.  However, if another driver can
make effective use of the byte-aligned capability it can claim namespace
interface and use the byte-aligned ->rw_bytes() interface.

The BTT driver is the initial first consumer of this mechanism to allow
adding atomic sector update semantics to a pmem or blk namespace.  This
patch is the sysfs infrastructure to allow configuring a BTT instance
for a namespace.  Enabling that BTT and performing i/o is in a
subsequent patch.

Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Neil Brown <neilb@suse.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2015-06-25 04:20:04 -04:00
Dan Williams 0ba1c63489 libnvdimm: write blk label set
After 'uuid', 'size', 'sector_size', and optionally 'alt_name' have been
set to valid values the labels on the dimm can be updated.  The
difference with the pmem case is that blk namespaces are limited to one
dimm and can cover discontiguous ranges in dpa space.

Also, after allocating label slots, it is useful for userspace to know
how many slots are left.  Export this information in sysfs.

Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Neil Brown <neilb@suse.de>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2015-06-24 21:24:10 -04:00
Dan Williams bf9bccc14c libnvdimm: pmem label sets and namespace instantiation.
A complete label set is a PMEM-label per-dimm per-interleave-set where
all the UUIDs match and the interleave set cookie matches the hosting
interleave set.

Present sysfs attributes for manipulation of a PMEM-namespace's
'alt_name', 'uuid', and 'size' attributes.  A later patch will make
these settings persistent by writing back the label.

Note that PMEM allocations grow forwards from the start of an interleave
set (lowest dimm-physical-address (DPA)).  BLK-namespaces that alias
with a PMEM interleave set will grow allocations backward from the
highest DPA.

Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Neil Brown <neilb@suse.de>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2015-06-24 21:24:10 -04:00
Dan Williams eaf961536e libnvdimm, nfit: add interleave-set state-tracking infrastructure
On platforms that have firmware support for reading/writing per-dimm
label space, a portion of the dimm may be accessible via an interleave
set PMEM mapping in addition to the dimm's BLK (block-data-window
aperture(s)) interface.  A label, stored in a "configuration data
region" on the dimm, disambiguates which dimm addresses are accessed
through which exclusive interface.

Add infrastructure that allows the kernel to block modifications to a
label in the set while any member dimm is active.  Note that this is
meant only for enforcing "no modifications of active labels" via the
coarse ioctl command.  Adding/deleting namespaces from an active
interleave set is always possible via sysfs.

Another aspect of tracking interleave sets is tracking their integrity
when DIMMs in a set are physically re-ordered.  For this purpose we
generate an "interleave-set cookie" that can be recorded in a label and
validated against the current configuration.  It is the bus provider
implementation's responsibility to calculate the interleave set cookie
and attach it to a given region.

Cc: Neil Brown <neilb@suse.de>
Cc: <linux-acpi@vger.kernel.org>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Robert Moore <robert.moore@intel.com>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2015-06-24 21:24:10 -04:00
Dan Williams 3d88002e4a libnvdimm: support for legacy (non-aliasing) nvdimms
The libnvdimm region driver is an intermediary driver that translates
non-volatile "region"s into "namespace" sub-devices that are surfaced by
persistent memory block-device drivers (PMEM and BLK).

ACPI 6 introduces the concept that a given nvdimm may simultaneously
offer multiple access modes to its media through direct PMEM load/store
access, or windowed BLK mode.  Existing nvdimms mostly implement a PMEM
interface, some offer a BLK-like mode, but never both as ACPI 6 defines.
If an nvdimm is single interfaced, then there is no need for dimm
metadata labels.  For these devices we can take the region boundaries
directly to create a child namespace device (nd_namespace_io).

Acked-by: Christoph Hellwig <hch@lst.de>
Tested-by: Toshi Kani <toshi.kani@hp.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2015-06-24 21:24:10 -04:00
Dan Williams 4d88a97aa9 libnvdimm, nvdimm: dimm driver and base libnvdimm device-driver infrastructure
* Implement the device-model infrastructure for loading modules and
  attaching drivers to nvdimm devices.  This is a simple association of a
  nd-device-type number with a driver that has a bitmask of supported
  device types.  To facilitate userspace bind/unbind operations 'modalias'
  and 'devtype', that also appear in the uevent, are added as generic
  sysfs attributes for all nvdimm devices.  The reason for the device-type
  number is to support sub-types within a given parent devtype, be it a
  vendor-specific sub-type or otherwise.

* The first consumer of this infrastructure is the driver
  for dimm devices.  It simply uses control messages to retrieve and
  store the configuration-data image (label set) from each dimm.

Note: nd_device_register() arranges for asynchronous registration of
      nvdimm bus devices by default.

Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Neil Brown <neilb@suse.de>
Acked-by: Christoph Hellwig <hch@lst.de>
Tested-by: Toshi Kani <toshi.kani@hp.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2015-06-24 21:24:10 -04:00
Dan Williams 62232e45f4 libnvdimm: control (ioctl) messages for nvdimm_bus and nvdimm devices
Most discovery/configuration of the nvdimm-subsystem is done via sysfs
attributes.  However, some nvdimm_bus instances, particularly the
ACPI.NFIT bus, define a small set of messages that can be passed to the
platform.  For convenience we derive the initial libnvdimm-ioctl command
formats directly from the NFIT DSM Interface Example formats.

    ND_CMD_SMART: media health and diagnostics
    ND_CMD_GET_CONFIG_SIZE: size of the label space
    ND_CMD_GET_CONFIG_DATA: read label space
    ND_CMD_SET_CONFIG_DATA: write label space
    ND_CMD_VENDOR: vendor-specific command passthrough
    ND_CMD_ARS_CAP: report address-range-scrubbing capabilities
    ND_CMD_ARS_START: initiate scrubbing
    ND_CMD_ARS_STATUS: report on scrubbing state
    ND_CMD_SMART_THRESHOLD: configure alarm thresholds for smart events

If a platform later defines different commands than this set it is
straightforward to extend support to those formats.

Most of the commands target a specific dimm.  However, the
address-range-scrubbing commands target the bus.  The 'commands'
attribute in sysfs of an nvdimm_bus, or nvdimm, enumerate the supported
commands for that object.

Cc: <linux-acpi@vger.kernel.org>
Cc: Robert Moore <robert.moore@intel.com>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reported-by: Nicholas Moulin <nicholas.w.moulin@linux.intel.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2015-06-24 21:24:10 -04:00
Dan Williams e6dfb2de47 libnvdimm, nfit: dimm/memory-devices
Enable nvdimm devices to be registered on a nvdimm_bus.  The kernel
assigned device id for nvdimm devicesis dynamic.  If userspace needs a
more static identifier it should consult a provider-specific attribute.
In the case where NFIT is the provider, the 'nmemX/nfit/handle' or
'nmemX/nfit/serial' attributes may be used for this purpose.

Cc: Neil Brown <neilb@suse.de>
Cc: <linux-acpi@vger.kernel.org>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Robert Moore <robert.moore@intel.com>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Toshi Kani <toshi.kani@hp.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2015-06-24 21:24:10 -04:00
Dan Williams 45def22c1f libnvdimm: control character device and nvdimm_bus sysfs attributes
The control device for a nvdimm_bus is registered as an "nd" class
device.  The expectation is that there will usually only be one "nd" bus
registered under /sys/class/nd.  However, we allow for the possibility
of multiple buses and they will listed in discovery order as
ndctl0...ndctlN.  This character device hosts the ioctl for passing
control messages.  The initial command set has a 1:1 correlation with
the commands listed in the by the "NFIT DSM Example" document [1], but
this scheme is extensible to future command sets.

Note, nd_ioctl() and the backing ->ndctl() implementation are defined in
a subsequent patch.  This is simply the initial registrations and sysfs
attributes.

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

Cc: Neil Brown <neilb@suse.de>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: <linux-acpi@vger.kernel.org>
Cc: Robert Moore <robert.moore@intel.com>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Toshi Kani <toshi.kani@hp.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2015-06-24 21:24:10 -04:00