summaryrefslogtreecommitdiff
path: root/drivers/nvdimm/dax_devs.c
AgeCommit message (Collapse)Author
2019-07-18libnvdimm/pfn: fix fsdax-mode namespace info-block zero-fieldsDan Williams
At namespace creation time there is the potential for the "expected to be zero" fields of a 'pfn' info-block to be filled with indeterminate data. While the kernel buffer is zeroed on allocation it is immediately overwritten by nd_pfn_validate() filling it with the current contents of the on-media info-block location. For fields like, 'flags' and the 'padding' it potentially means that future implementations can not rely on those fields being zero. In preparation to stop using the 'start_pad' and 'end_trunc' fields for section alignment, arrange for fields that are not explicitly initialized to be guaranteed zero. Bump the minor version to indicate it is safe to assume the 'padding' and 'flags' are zero. Otherwise, this corruption is expected to benign since all other critical fields are explicitly initialized. Note The cc: stable is about spreading this new policy to as many kernels as possible not fixing an issue in those kernels. It is not until the change titled "libnvdimm/pfn: Stop padding pmem namespaces to section alignment" where this improper initialization becomes a problem. So if someone decides to backport "libnvdimm/pfn: Stop padding pmem namespaces to section alignment" (which is not tagged for stable), make sure this pre-requisite is flagged. Link: http://lkml.kernel.org/r/156092356065.979959.6681003754765958296.stgit@dwillia2-desk3.amr.corp.intel.com Fixes: 32ab0a3f5170 ("libnvdimm, pmem: 'struct page' for pmem") Signed-off-by: Dan Williams <dan.j.williams@intel.com> Tested-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> [ppc64] Cc: <stable@vger.kernel.org> Cc: David Hildenbrand <david@redhat.com> Cc: Jane Chu <jane.chu@oracle.com> Cc: Jeff Moyer <jmoyer@redhat.com> Cc: Jérôme Glisse <jglisse@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Logan Gunthorpe <logang@deltatee.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@linux.ibm.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Pavel Tatashin <pasha.tatashin@soleen.com> Cc: Toshi Kani <toshi.kani@hpe.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Wei Yang <richardw.yang@linux.intel.com> Cc: Jason Gunthorpe <jgg@mellanox.com> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-06-05treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 295Thomas Gleixner
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of version 2 of the gnu general public license as published by the free software foundation this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 64 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Alexios Zavras <alexios.zavras@intel.com> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190529141901.894819585@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-06libnvdimm: remove redundant __func__ in dev_dbgDan Williams
Dynamic debug can be instructed to add the function name to the debug output using the +f switch, so there is no need for the libnvdimm modules to do it again. If a user decides to add the +f switch for libnvdimm's dynamic debug this results in double prints of the function name. Reported-by: Johannes Thumshirn <jthumshirn@suse.de> Reported-by: Ross Zwisler <ross.zwisler@linux.intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-07-03Merge branch 'for-4.13/dax' into libnvdimm-for-nextDan Williams
2017-06-27libnvdimm, nfit: enable support for volatile rangesDan Williams
Allow volatile nfit ranges to participate in all the same infrastructure provided for persistent memory regions. A resulting resulting namespace device will still be called "pmem", but the parent region type will be "nd_volatile". This is in preparation for disabling the dax ->flush() operation in the pmem driver when it is hosted on a volatile range. Cc: Jan Kara <jack@suse.cz> Cc: Jeff Moyer <jmoyer@redhat.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Matthew Wilcox <mawilcox@microsoft.com> Cc: Ross Zwisler <ross.zwisler@linux.intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-06-15libnvdimm, label: add address abstraction identifiersDan Williams
Starting with v1.2 labels, 'address abstractions' can be hinted via an address abstraction id that implies an info-block format. The standard address abstraction in the specification is the v2 format of the Block-Translation-Table (BTT). Support for that is saved for a later patch, for now we add support for the Linux supported address abstractions BTT (v1), PFN, and DAX. The new 'holder_class' attribute for namespace devices is added for tooling to specify the 'abstraction_guid' to store in the namespace label. For v1.1 labels this field is undefined and any setting of 'holder_class' away from the default 'none' value will only have effect until the driver is unloaded. Setting 'holder_class' requires that whatever device tries to claim the namespace must be of the specified class. Cc: Vishal Verma <vishal.l.verma@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-05-01libnvdimm: fix nvdimm_bus_lock() vs device_lock() orderingDan Williams
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: 8c2f7e8658df ("libnvdimm: infrastructure for btt devices") Reported-by: Yi Zhang <yizhan@redhat.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2016-05-20libnvdimm, dax: autodetect supportDan Williams
For autodetecting a previously established dax configuration we need the info block to indicate block-device vs device-dax mode, and we need to have the default namespace probe hand-off the configuration to the dax_pmem driver. Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2016-05-09libnvdimm, dax: introduce device-dax infrastructureDan Williams
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>