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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>
2018-03-02libnvdimm: re-enable deep flush for pmem devices via fsync()Dave Jiang
Re-enable deep flush so that users always have a way to be sure that a write makes it all the way out to media. Writes from the PMEM driver always arrive at the NVDIMM since movnt is used to bypass the cache, and the driver relies on the ADR (Asynchronous DRAM Refresh) mechanism to flush write buffers on power failure. The Deep Flush mechanism is there to explicitly write buffers to protect against (rare) ADR failure. This change prevents a regression in deep flush behavior so that applications can continue to depend on fsync() as a mechanism to trigger deep flush in the filesystem-DAX case. Fixes: 06e8ccdab15f4 ("acpi: nfit: Add support for detect platform CPU cache...") Reviewed-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2018-02-28block: Add 'lock' as third argument to blk_alloc_queue_node()Bart Van Assche
This patch does not change any functionality. Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com> Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Philipp Reisner <philipp.reisner@linbit.com> Cc: Ulf Hansson <ulf.hansson@linaro.org> Cc: Kees Cook <keescook@chromium.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-02-03Merge branch 'for-4.16/nfit' into libnvdimm-for-nextRoss Zwisler
2018-02-03Merge branch 'for-4.16/dax' into libnvdimm-for-nextRoss Zwisler
2018-02-03libnvdimm, namespace: remove redundant initialization of 'nd_mapping'Colin Ian King
Pointer nd_mapping is being initialized to a value that is never read, instead it is being updated to a new value in all the cases where it is being read afterwards, hence the initialization is redundant and can be removed. Cleans up clang warning: drivers/nvdimm/namespace_devs.c:2411:21: warning: Value stored to 'nd_mapping' during its initialization is never rea Signed-off-by: Colin Ian King <colin.king@canonical.com> Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com> Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
2018-02-01libnvdimm: expose platform persistence attribute for nd_regionDave Jiang
Providing a sysfs attribute for nd_region that shows the persistence capabilities for the platform. Signed-off-by: Dave Jiang <dave.jiang@intel.com> Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com> Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
2018-02-01acpi: nfit: Add support for detect platform CPU cache flush on power lossDave Jiang
In ACPI 6.2a the platform capability structure has been added to the NFIT tables. That provides software the ability to determine whether a system supports the auto flushing of CPU caches on power loss. If the capability is supported, we do not need to do dax_flush(). Plumbing the path to set the property on per region from the NFIT tables. This patch depends on the ACPI NFIT 6.2a platform capabilities support code in include/acpi/actbl1.h. Signed-off-by: Dave Jiang <dave.jiang@intel.com> Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com> Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
2018-01-19libnvdimm, btt: fix uninitialized err_lockJeff Moyer
When a sector mode namespace is initially created, the arena's err_lock is not initialized. If, on the other hand, the namespace already exists, the mutex is initialized. To fix the issue, I moved the mutex initialization into the arena_alloc, which is called by both discover_arenas and create_arenas. This was discovered on an older kernel where mutex_trylock checks the count to determine whether the lock is held. Because the data structure is kzalloc-d, that count was 0 (held), and I/O to the device would hang forever waiting for the lock to be released (see btt_write_pg, for example). Current kernels have a different mutex implementation that checks for a non-null owner, and so this doesn't show up as a problem. If that lock were ever contended, it might cause issues, but you'd have to be really unlucky, I think. Signed-off-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2018-01-08memremap: change devm_memremap_pages interface to use struct dev_pagemapChristoph Hellwig
This new interface is similar to how struct device (and many others) work. The caller initializes a 'struct dev_pagemap' as required and calls 'devm_memremap_pages'. This allows the pagemap structure to be embedded in another structure and thus container_of can be used. In this way application specific members can be stored in a containing struct. This will be used by the P2P infrastructure and HMM could probably be cleaned up to use it as well (instead of having it's own, similar 'hmm_devmem_pages_create' function). Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-12-21libnvdimm, btt: Fix an incompatibility in the log layoutVishal Verma
Due to a spec misinterpretation, the Linux implementation of the BTT log area had different padding scheme from other implementations, such as UEFI and NVML. This fixes the padding scheme, and defaults to it for new BTT layouts. We attempt to detect the padding scheme in use when probing for an existing BTT. If we detect the older/incompatible scheme, we continue using it. Reported-by: Juston Li <juston.li@intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: <stable@vger.kernel.org> Fixes: 5212e11fde4d ("nd_btt: atomic sector updates") Signed-off-by: Vishal Verma <vishal.l.verma@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-12-21libnvdimm, btt: add a couple of missing kernel-doc linesVishal Verma
Recent updates to btt.h neglected to add corresponding kernel-doc lines for new structure members. Add them. Signed-off-by: Vishal Verma <vishal.l.verma@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-12-19libnvdimm, dax: fix 1GB-aligned namespaces vs physical misalignmentDan Williams
The following namespace configuration attempt: # ndctl create-namespace -e namespace0.0 -m devdax -a 1G -f libndctl: ndctl_dax_enable: dax0.1: failed to enable Error: namespace0.0: failed to enable failed to reconfigure namespace: No such device or address ...fails when the backing memory range is not physically aligned to 1G: # cat /proc/iomem | grep Persistent 210000000-30fffffff : Persistent Memory (legacy) In the above example the 4G persistent memory range starts and ends on a 256MB boundary. We handle this case correctly when needing to handle cases that violate section alignment (128MB) collisions against "System RAM", and we simply need to extend that padding/truncation for the 1GB alignment use case. Cc: <stable@vger.kernel.org> Fixes: 315c562536c4 ("libnvdimm, pfn: add 'align' attribute...") Reported-and-tested-by: Jane Chu <jane.chu@oracle.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-12-19libnvdimm, pfn: fix start_pad handling for aligned namespacesDan Williams
The alignment checks at pfn driver startup fail to properly account for the 'start_pad' in the case where the namespace is misaligned relative to its internal alignment. This is typically triggered in 1G aligned namespace, but could theoretically trigger with small namespace alignments. When this triggers the kernel reports messages of the form: dax2.1: bad offset: 0x3c000000 dax disabled align: 0x40000000 Cc: <stable@vger.kernel.org> Fixes: 1ee6667cd8d1 ("libnvdimm, pfn, dax: fix initialization vs autodetect...") Reported-by: Jane Chu <jane.chu@oracle.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-12-04nfit, libnvdimm: deprecate the generic SMART ioctlDan Williams
The kernel's ND_IOCTL_SMART_THRESHOLD command is based on a payload definition that has become broken / out-of-sync with recent versions of the NVDIMM_FAMILY_INTEL definition. Deprecate the use of the ND_IOCTL_SMART_THRESHOLD command in favor of the ND_CMD_CALL approach taken by NVDIMM_FAMILY_{HPE,MSFT}, where we can manage the per-vendor variance in userspace. In a couple years, when the new scheme is widely deployed in userspace packages, the ND_IOCTL_SMART_THRESHOLD support can be removed. For now we prevent new binaries from compiling against the kernel header definitions, but kernel still compatible with old binaries. The libndctl.h [1] header is now the authoritative interface definition for NVDIMM SMART. [1]: https://github.com/pmem/ndctl Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-11-17Merge tag 'libnvdimm-for-4.15' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm Pull libnvdimm and dax updates from Dan Williams: "Save for a few late fixes, all of these commits have shipped in -next releases since before the merge window opened, and 0day has given a build success notification. The ext4 touches came from Jan, and the xfs touches have Darrick's reviewed-by. An xfstest for the MAP_SYNC feature has been through a few round of reviews and is on track to be merged. - Introduce MAP_SYNC and MAP_SHARED_VALIDATE, a mechanism to enable 'userspace flush' of persistent memory updates via filesystem-dax mappings. It arranges for any filesystem metadata updates that may be required to satisfy a write fault to also be flushed ("on disk") before the kernel returns to userspace from the fault handler. Effectively every write-fault that dirties metadata completes an fsync() before returning from the fault handler. The new MAP_SHARED_VALIDATE mapping type guarantees that the MAP_SYNC flag is validated as supported by the filesystem's ->mmap() file operation. - Add support for the standard ACPI 6.2 label access methods that replace the NVDIMM_FAMILY_INTEL (vendor specific) label methods. This enables interoperability with environments that only implement the standardized methods. - Add support for the ACPI 6.2 NVDIMM media error injection methods. - Add support for the NVDIMM_FAMILY_INTEL v1.6 DIMM commands for latch last shutdown status, firmware update, SMART error injection, and SMART alarm threshold control. - Cleanup physical address information disclosures to be root-only. - Fix revalidation of the DIMM "locked label area" status to support dynamic unlock of the label area. - Expand unit test infrastructure to mock the ACPI 6.2 Translate SPA (system-physical-address) command and error injection commands. Acknowledgements that came after the commits were pushed to -next: - 957ac8c421ad ("dax: fix PMD faults on zero-length files"): Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com> - a39e596baa07 ("xfs: support for synchronous DAX faults") and 7b565c9f965b ("xfs: Implement xfs_filemap_pfn_mkwrite() using __xfs_filemap_fault()") Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>" * tag 'libnvdimm-for-4.15' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (49 commits) acpi, nfit: add 'Enable Latch System Shutdown Status' command support dax: fix general protection fault in dax_alloc_inode dax: fix PMD faults on zero-length files dax: stop requiring a live device for dax_flush() brd: remove dax support dax: quiet bdev_dax_supported() fs, dax: unify IOMAP_F_DIRTY read vs write handling policy in the dax core tools/testing/nvdimm: unit test clear-error commands acpi, nfit: validate commands against the device type tools/testing/nvdimm: stricter bounds checking for error injection commands xfs: support for synchronous DAX faults xfs: Implement xfs_filemap_pfn_mkwrite() using __xfs_filemap_fault() ext4: Support for synchronous DAX faults ext4: Simplify error handling in ext4_dax_huge_fault() dax: Implement dax_finish_sync_fault() dax, iomap: Add support for synchronous faults mm: Define MAP_SYNC and VM_SYNC flags dax: Allow tuning whether dax_insert_mapping_entry() dirties entry dax: Allow dax_iomap_fault() to return pfn dax: Fix comment describing dax_iomap_fault() ...
2017-11-15bdi: introduce BDI_CAP_SYNCHRONOUS_IOMinchan Kim
As discussed at https://lkml.kernel.org/r/<20170728165604.10455-1-ross.zwisler@linux.intel.com> someday we will remove rw_page(). If so, we need something to detect such super-fast storage on which synchronous IO operations like the current rw_page are always a win. Introduces BDI_CAP_SYNCHRONOUS_IO to indicate such devices. With it, we could use various optimization techniques. Link: http://lkml.kernel.org/r/1505886205-9671-3-git-send-email-minchan@kernel.org Signed-off-by: Minchan Kim <minchan@kernel.org> Cc: Christoph Hellwig <hch@lst.de> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Ross Zwisler <ross.zwisler@linux.intel.com> Cc: Hugh Dickins <hughd@google.com> Cc: Ilya Dryomov <idryomov@gmail.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Cc: Huang Ying <ying.huang@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-15Merge branch 'for-linus' of ↵Linus Torvalds
ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/jikos/trivial Pull trivial tree updates from Jiri Kosina: "The usual rocket-science from trivial tree for 4.15" * 'for-linus' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: MAINTAINERS: relinquish kconfig MAINTAINERS: Update my email address treewide: Fix typos in Kconfig kfifo: Fix comments init/Kconfig: Fix module signing document location misc: ibmasm: Return error on error path HID: logitech-hidpp: fix mistake in printk, "feeback" -> "feedback" MAINTAINERS: Correct path to uDraw PS3 driver tracing: Fix doc mistakes in trace sample tracing: Kconfig text fixes for CONFIG_HWLAT_TRACER MIPS: Alchemy: Remove reverted CONFIG_NETLINK_MMAP from db1xxx_defconfig mm/huge_memory.c: fixup grammar in comment lib/xz: Add fall-through comments to a switch statement
2017-11-02libnvdimm, badrange: remove a WARN for list_emptyVishal Verma
Now that we're reusing the badrange functions for nfit_test, and that exposes badrange injection/clearing to userspace via the DSM paths, it is plausible that a user may call the clear DSM multiple times. Since it is harmless to do so, we can remove the WARN in badrange_forget. Cc: Dave Jiang <dave.jiang@intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Vishal Verma <vishal.l.verma@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-11-02libnvdimm: move poison list functions to a new 'badrange' fileDave Jiang
nfit_test needs to use the poison list manipulation code as well. Make it more generic and in the process rename poison to badrange, and move all the related helpers to a new file. Signed-off-by: Dave Jiang <dave.jiang@intel.com> [vishal: Add badrange.o to nfit_test's Kbuild] [vishal: add a missed include in bus.c for the new badrange functions] [vishal: rename all instances of 'be' to 'bre'] Signed-off-by: Vishal Verma <vishal.l.verma@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-11-02License cleanup: add SPDX GPL-2.0 license identifier to files with no licenseGreg Kroah-Hartman
Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-10-12treewide: Fix typos in KconfigMasanari Iida
This patch fixes some spelling typos found in Kconfig files. Signed-off-by: Masanari Iida <standby24x7@gmail.com> Acked-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2017-10-07libnvdimm, namespace: make a couple of functions staticColin Ian King
The functions create_namespace_pmem and create_namespace_blk are local to the source and do not need to be in global scope, so make them static. Cleans up sparse warnings: symbol 'create_namespace_pmem' was not declared. Should it be static? symbol 'create_namespace_blk' was not declared. Should it be static? Signed-off-by: Colin Ian King <colin.king@canonical.com> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-10-07libnvdimm: introduce 'flags' attribute for DIMM 'lock' and 'alias' statusDan Williams
Given that we now how have two mechanisms for a DIMM to indicate that it is locked: * NVDIMM_FAMILY_INTEL 'get_config_size' _DSM command * ACPI 6.2 Label Storage Read / Write commands ...export the generic libnvdimm DIMM status in a new 'flags' attribute. This attribute can also reflect the 'alias' state which indicates whether the nvdimm core is enforcing labels for aliased-region-capacity that the given dimm is an interleave-set member. Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-10-07acpi, nfit: add support for the _LSI, _LSR, and _LSW label methodsDan Williams
ACPI 6.2 adds support for named methods to access the label storage area of an NVDIMM. We prefer these new methods if available and otherwise fallback to the NVDIMM_FAMILY_INTEL _DSMs. The kernel ioctls, ND_IOCTL_{GET,SET}_CONFIG_{SIZE,DATA}, remain generic and the driver translates the 'package' payloads into the NVDIMM_FAMILY_INTEL 'buffer' format to maintain compatibility with existing userspace and keep the output buffer parsing code in the driver common. The output payloads are mostly compatible save for the 'label area locked' status that moves from the 'config_size' (_LSI) command to the 'config_read' (_LSR) command status. Cc: Jeff Moyer <jmoyer@redhat.com> Cc: Johannes Thumshirn <jthumshirn@suse.de> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-09-28libnvdimm, namespace: fix label initialization to use valid seq numbersDan Williams
The set of valid sequence numbers is {1,2,3}. The specification indicates that an implementation should consider 0 a sign of a critical error: UEFI 2.7: 13.19 NVDIMM Label Protocol Software never writes the sequence number 00, so a correctly check-summed Index Block with this sequence number probably indicates a critical error. When software discovers this case it treats it as an invalid Index Block indication. While the expectation is that the invalid block is just thrown away, the Robustness Principle says we should fix this to make both sequence numbers valid. Fixes: f524bf271a5c ("libnvdimm: write pmem label set") Cc: <stable@vger.kernel.org> Reported-by: Juston Li <juston.li@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-09-28libnvdimm, pfn: make 'resource' attribute only readable by rootDan Williams
For the same reason that /proc/iomem returns 0's for non-root readers and acpi tables are root-only, make the 'resource' attribute for pfn devices only readable by root. Otherwise we disclose physical address information. Fixes: f6ed58c70d14 ("libnvdimm, pfn: 'resource'-address and 'size'...") Cc: <stable@vger.kernel.org> Reported-by: Dave Hansen <dave.hansen@linux.intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-09-28libnvdimm, namespace: make 'resource' attribute only readable by rootDan Williams
For the same reason that /proc/iomem returns 0's for non-root readers and acpi tables are root-only, make the 'resource' attribute for namespace devices only readable by root. Otherwise we disclose physical address information. Fixes: bf9bccc14c05 ("libnvdimm: pmem label sets and namespace instantiation") Cc: <stable@vger.kernel.org> Reported-by: Dave Hansen <dave.hansen@linux.intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-09-28libnvdimm, region : make 'resource' attribute only readable by rootDan Williams
For the same reason that /proc/iomem returns 0's for non-root readers and acpi tables are root-only, make the 'resource' attribute for region devices only readable by root. Otherwise we disclose physical address information. Fixes: 802f4be6feee ("libnvdimm: Add 'resource' sysfs attribute to regions") Cc: <stable@vger.kernel.org> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Johannes Thumshirn <jthumshirn@suse.de> Reported-by: Dave Hansen <dave.hansen@linux.intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-09-28libnvdimm, dimm: clear 'locked' status on successful DIMM enableDan Williams
If we successfully enable a DIMM then it must not be locked and we can clear the label-read failure condition. Otherwise, we need to reload the entire bus provider driver to achieve the same effect, and that can disrupt unrelated DIMMs and namespaces. Fixes: 9d62ed965118 ("libnvdimm: handle locked label storage areas") Cc: <stable@vger.kernel.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-09-18libnvdimm, namespace: fix btt claim class crashDan Williams
Maurice reports: BUG: unable to handle kernel NULL pointer dereference at 0000000000000028 IP: holder_class_store+0x253/0x2b0 [libnvdimm] ...while trying to reconfigure an NVDIMM-N namespace into 'sector' / 'btt' mode. The crash points to this line: (gdb) li *(holder_class_store+0x253) 0x7773 is in holder_class_store (drivers/nvdimm/namespace_devs.c:1420). 1415 for (i = 0; i < nd_region->ndr_mappings; i++) { 1416 struct nd_mapping *nd_mapping = &nd_region->mapping[i]; 1417 struct nvdimm_drvdata *ndd = to_ndd(nd_mapping); 1418 struct nd_namespace_index *nsindex; 1419 1420 nsindex = to_namespace_index(ndd, ndd->ns_current); ...where we are failing because ndd is NULL due to NVDIMM-N dimms not supporting labels. Long story short, default to the BTTv1 format in the label-less / NVDIMM-N case. Fixes: 14e494542636 ("libnvdimm, btt: BTT updates for UEFI 2.7 format") Cc: <stable@vger.kernel.org> Cc: Vishal Verma <vishal.l.verma@intel.com> Reported-by: Maurice A. Saldivar <maurice.a.saldivar@hpe.com> Tested-by: Maurice A. Saldivar <maurice.a.saldivar@hpe.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-09-14Merge tag 'for-4.14/dm-changes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm Pull device mapper updates from Mike Snitzer: - Some request-based DM core and DM multipath fixes and cleanups - Constify a few variables in DM core and DM integrity - Add bufio optimization and checksum failure accounting to DM integrity - Fix DM integrity to avoid checking integrity of failed reads - Fix DM integrity to use init_completion - A couple DM log-writes target fixes - Simplify DAX flushing by eliminating the unnecessary flush abstraction that was stood up for DM's use. * tag 'for-4.14/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: dax: remove the pmem_dax_ops->flush abstraction dm integrity: use init_completion instead of COMPLETION_INITIALIZER_ONSTACK dm integrity: make blk_integrity_profile structure const dm integrity: do not check integrity for failed read operations dm log writes: fix >512b sectorsize support dm log writes: don't use all the cpu while waiting to log blocks dm ioctl: constify ioctl lookup table dm: constify argument arrays dm integrity: count and display checksum failures dm integrity: optimize writing dm-bufio buffers that are partially changed dm rq: do not update rq partially in each ending bio dm rq: make dm-sq requeuing behavior consistent with dm-mq behavior dm mpath: complain about unsupported __multipath_map_bio() return values dm mpath: avoid that building with W=1 causes gcc 7 to complain about fall-through
2017-09-11Merge tag 'libnvdimm-for-4.14' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm Pull libnvdimm from Dan Williams: "A rework of media error handling in the BTT driver and other updates. It has appeared in a few -next releases and collected some late- breaking build-error and warning fixups as a result. Summary: - Media error handling support in the Block Translation Table (BTT) driver is reworked to address sleeping-while-atomic locking and memory-allocation-context conflicts. - The dax_device lookup overhead for xfs and ext4 is moved out of the iomap hot-path to a mount-time lookup. - A new 'ecc_unit_size' sysfs attribute is added to advertise the read-modify-write boundary property of a persistent memory range. - Preparatory fix-ups for arm and powerpc pmem support are included along with other miscellaneous fixes" * tag 'libnvdimm-for-4.14' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (26 commits) libnvdimm, btt: fix format string warnings libnvdimm, btt: clean up warning and error messages ext4: fix null pointer dereference on sbi libnvdimm, nfit: move the check on nd_reserved2 to the endpoint dax: fix FS_DAX=n BLOCK=y compilation libnvdimm: fix integer overflow static analysis warning libnvdimm, nd_blk: remove mmio_flush_range() libnvdimm, btt: rework error clearing libnvdimm: fix potential deadlock while clearing errors libnvdimm, btt: cache sector_size in arena_info libnvdimm, btt: ensure that flags were also unchanged during a map_read libnvdimm, btt: refactor map entry operations with macros libnvdimm, btt: fix a missed NVDIMM_IO_ATOMIC case in the write path libnvdimm, nfit: export an 'ecc_unit_size' sysfs attribute ext4: perform dax_device lookup at mount ext2: perform dax_device lookup at mount xfs: perform dax_device lookup at mount dax: introduce a fs_dax_get_by_bdev() helper libnvdimm, btt: check memory allocation failure libnvdimm, label: fix index block size calculation ...
2017-09-11dax: remove the pmem_dax_ops->flush abstractionMikulas Patocka
Commit abebfbe2f731 ("dm: add ->flush() dax operation support") is buggy. A DM device may be composed of multiple underlying devices and all of them need to be flushed. That commit just routes the flush request to the first device and ignores the other devices. It could be fixed by adding more complex logic to the device mapper. But there is only one implementation of the method pmem_dax_ops->flush - that is pmem_dax_flush() - and it calls arch_wb_cache_pmem(). Consequently, we don't need the pmem_dax_ops->flush abstraction at all, we can call arch_wb_cache_pmem() directly from dax_flush() because dax_dev->ops->flush can't ever reach anything different from arch_wb_cache_pmem(). It should be also pointed out that for some uses of persistent memory it is needed to flush only a very small amount of data (such as 1 cacheline), and it would be overkill if we go through that device mapper machinery for a single flushed cache line. Fix this by removing the pmem_dax_ops->flush abstraction and call arch_wb_cache_pmem() directly from dax_flush(). Also, remove the device mapper code that forwards the flushes. Fixes: abebfbe2f731 ("dm: add ->flush() dax operation support") Cc: stable@vger.kernel.org Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2017-09-09libnvdimm, btt: fix format string warningsRandy Dunlap
Fix format warnings (seen on i386) in nvdimm/btt.c: ../drivers/nvdimm/btt.c: In function ‘btt_map_init’: ../drivers/nvdimm/btt.c:430:3: warning: format ‘%lx’ expects argument of type ‘long unsigned int’, but argument 4 has type ‘size_t’ [-Wformat=] dev_WARN_ONCE(to_dev(arena), size < 512, ^ ../drivers/nvdimm/btt.c: In function ‘btt_log_init’: ../drivers/nvdimm/btt.c:474:3: warning: format ‘%lx’ expects argument of type ‘long unsigned int’, but argument 4 has type ‘size_t’ [-Wformat=] dev_WARN_ONCE(to_dev(arena), size < 512, ^ Fixes: 86652d2eb347 ("libnvdimm, btt: clean up warning and error messages") Reported-by: Arnd Bergmann <arnd@arndb.de> Reported-by: kbuild test robot <fengguang.wu@intel.com> Cc: Vishal Verma <vishal.l.verma@intel.com> Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-09-07libnvdimm, btt: clean up warning and error messagesVishal Verma
Convert all WARN* style messages to dev_WARN, and for errors in the IO paths, use dev_err_ratelimited. Also remove some BUG_ONs in the IO path and replace them with the above - no need to crash the machine in case of an unaligned IO. Cc: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Vishal Verma <vishal.l.verma@intel.com> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-09-07Merge branch 'for-4.14/block' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull block layer updates from Jens Axboe: "This is the first pull request for 4.14, containing most of the code changes. It's a quiet series this round, which I think we needed after the churn of the last few series. This contains: - Fix for a registration race in loop, from Anton Volkov. - Overflow complaint fix from Arnd for DAC960. - Series of drbd changes from the usual suspects. - Conversion of the stec/skd driver to blk-mq. From Bart. - A few BFQ improvements/fixes from Paolo. - CFQ improvement from Ritesh, allowing idling for group idle. - A few fixes found by Dan's smatch, courtesy of Dan. - A warning fixup for a race between changing the IO scheduler and device remova. From David Jeffery. - A few nbd fixes from Josef. - Support for cgroup info in blktrace, from Shaohua. - Also from Shaohua, new features in the null_blk driver to allow it to actually hold data, among other things. - Various corner cases and error handling fixes from Weiping Zhang. - Improvements to the IO stats tracking for blk-mq from me. Can drastically improve performance for fast devices and/or big machines. - Series from Christoph removing bi_bdev as being needed for IO submission, in preparation for nvme multipathing code. - Series from Bart, including various cleanups and fixes for switch fall through case complaints" * 'for-4.14/block' of git://git.kernel.dk/linux-block: (162 commits) kernfs: checking for IS_ERR() instead of NULL drbd: remove BIOSET_NEED_RESCUER flag from drbd_{md_,}io_bio_set drbd: Fix allyesconfig build, fix recent commit drbd: switch from kmalloc() to kmalloc_array() drbd: abort drbd_start_resync if there is no connection drbd: move global variables to drbd namespace and make some static drbd: rename "usermode_helper" to "drbd_usermode_helper" drbd: fix race between handshake and admin disconnect/down drbd: fix potential deadlock when trying to detach during handshake drbd: A single dot should be put into a sequence. drbd: fix rmmod cleanup, remove _all_ debugfs entries drbd: Use setup_timer() instead of init_timer() to simplify the code. drbd: fix potential get_ldev/put_ldev refcount imbalance during attach drbd: new disk-option disable-write-same drbd: Fix resource role for newly created resources in events2 drbd: mark symbols static where possible drbd: Send P_NEG_ACK upon write error in protocol != C drbd: add explicit plugging when submitting batches drbd: change list_for_each_safe to while(list_first_entry_or_null) drbd: introduce drbd_recv_header_maybe_unplug ...
2017-09-06block, THP: make block_device_operations.rw_page support THPHuang Ying
The .rw_page in struct block_device_operations is used by the swap subsystem to read/write the page contents from/into the corresponding swap slot in the swap device. To support the THP (Transparent Huge Page) swap optimization, the .rw_page is enhanced to support to read/write THP if possible. Link: http://lkml.kernel.org/r/20170724051840.2309-6-ying.huang@intel.com Signed-off-by: "Huang, Ying" <ying.huang@intel.com> Reviewed-by: Ross Zwisler <ross.zwisler@intel.com> [for brd.c, zram_drv.c, pmem.c] Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Minchan Kim <minchan@kernel.org> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Vishal L Verma <vishal.l.verma@intel.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Hugh Dickins <hughd@google.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Rik van Riel <riel@redhat.com> Cc: Shaohua Li <shli@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-09-04libnvdimm, nfit: move the check on nd_reserved2 to the endpointMeng Xu
Delay the check of nd_reserved2 to the actual endpoint (acpi_nfit_ctl) that uses it, as a prevention of a potential double-fetch bug. While examining the kernel source code, I found a dangerous operation that could turn into a double-fetch situation (a race condition bug) where the same userspace memory region are fetched twice into kernel with sanity checks after the first fetch while missing checks after the second fetch. In the case of _IOC_NR(ioctl_cmd) == ND_CMD_CALL: 1. The first fetch happens in line 935 copy_from_user(&pkg, p, sizeof(pkg) 2. subsequently `pkg.nd_reserved2` is asserted to be all zeroes (line 984 to 986). 3. The second fetch happens in line 1022 copy_from_user(buf, p, buf_len) 4. Given that `p` can be fully controlled in userspace, an attacker can race condition to override the header part of `p`, say, `((struct nd_cmd_pkg *)p)->nd_reserved2` to arbitrary value (say nine 0xFFFFFFFF for `nd_reserved2`) after the first fetch but before the second fetch. The changed value will be copied to `buf`. 5. There is no checks on the second fetches until the use of it in line 1034: nd_cmd_clear_to_send(nvdimm_bus, nvdimm, cmd, buf) and line 1038: nd_desc->ndctl(nd_desc, nvdimm, cmd, buf, buf_len, &cmd_rc) which means that the assumed relation, `p->nd_reserved2` are all zeroes might not hold after the second fetch. And once the control goes to these functions we lose the context to assert the assumed relation. 6. Based on my manual analysis, `p->nd_reserved2` is not used in function `nd_cmd_clear_to_send` and potential implementations of `nd_desc->ndctl` so there is no working exploit against it right now. However, this could easily turns to an exploitable one if careless developers start to use `p->nd_reserved2` later and assume that they are all zeroes. Move the validation of the nd_reserved2 field to the ->ndctl() implementation where it has a stable buffer to evaluate. Signed-off-by: Meng Xu <mengxu.gatech@gmail.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-08-31libnvdimm: fix integer overflow static analysis warningDan Williams
Dan reports: The patch 62232e45f4a2: "libnvdimm: control (ioctl) messages for nvdimm_bus and nvdimm devices" from Jun 8, 2015, leads to the following static checker warning: drivers/nvdimm/bus.c:1018 __nd_ioctl() warn: integer overflows 'buf_len' From a casual review, this seems like it might be a real bug. On the first iteration we load some data into in_env[]. On the second iteration we read a use controlled "in_size" from nd_cmd_in_size(). It can go up to UINT_MAX - 1. A high number means we will fill the whole in_env[] buffer. But we potentially keep looping and adding more to in_len so now it can be any value. It simple enough to change, but it feels weird that we keep looping even though in_env is totally full. Shouldn't we just return an error if we don't have space for desc->in_num. We keep looping because the size of the total input is allowed to be bigger than the 'envelope' which is a subset of the payload that tells us how much data to expect. For safety explicitly check that buf_len does not overflow which is what the checker flagged. Cc: <stable@vger.kernel.org> Fixes: 62232e45f4a2: "libnvdimm: control (ioctl) messages for nvdimm_bus..." Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-08-31libnvdimm, nd_blk: remove mmio_flush_range()Robin Murphy
mmio_flush_range() suffers from a lack of clearly-defined semantics, and is somewhat ambiguous to port to other architectures where the scope of the writeback implied by "flush" and ordering might matter, but MMIO would tend to imply non-cacheable anyway. Per the rationale in 67a3e8fe9015 ("nd_blk: change aperture mapping from WC to WB"), the only existing use is actually to invalidate clean cache lines for ARCH_MEMREMAP_PMEM type mappings *without* writeback. Since the recent cleanup of the pmem API, that also now happens to be the exact purpose of arch_invalidate_pmem(), which would be a far more well-defined tool for the job. Rather than risk potentially inconsistent implementations of mmio_flush_range() for the sake of one callsite, streamline things by removing it entirely and instead move the ARCH_MEMREMAP_PMEM related definitions up to the libnvdimm level, so they can be shared by NFIT as well. This allows NFIT to be enabled for arm64. Signed-off-by: Robin Murphy <robin.murphy@arm.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-08-31libnvdimm, btt: rework error clearingVishal Verma
Clearing errors or badblocks during a BTT write requires sending an ACPI DSM, which means potentially sleeping. Since a BTT IO happens in atomic context (preemption disabled, spinlocks may be held), we cannot perform error clearing in the course of an IO. Due to this error clearing for BTT IOs has hitherto been disabled. In this patch we move error clearing out of the atomic section, and thus re-enable error clearing with BTTs. When we are about to add a block to the free list, we check if it was previously marked as an error, and if it was, we add it to the freelist, but also set a flag that says error clearing will be required. We then drop the lane (ending the atomic context), and send a zero buffer so that the error can be cleared. The error flag in the free list is protected by the nd 'lane', and is set only be a thread while it holds that lane. When the error is cleared, the flag is cleared, but while holding a mutex for that freelist index. When writing, we check for two things - 1/ If the freelist mutex is held or if the error flag is set. If so, this is an error block that is being (or about to be) cleared. 2/ If the block is a known badblock based on nsio->bb The second check is required because the BTT map error flag for a map entry only gets set when an error LBA is read. If we write to a new location that may not have the map error flag set, but still might be in the region's badblock list, we can trigger an EIO on the write, which is undesirable and completely avoidable. Cc: Jeff Moyer <jmoyer@redhat.com> Cc: Toshi Kani <toshi.kani@hpe.com> Cc: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Vishal Verma <vishal.l.verma@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-08-31libnvdimm: fix potential deadlock while clearing errorsVishal Verma
With the ACPI NFIT 'DSM' methods, acpi can be called from IO paths. Specifically, the DSM to clear media errors is called during writes, so that we can provide a writes-fix-errors model. However it is easy to imagine a scenario like: -> write through the nvdimm driver -> acpi allocation -> writeback, causes more IO through the nvdimm driver -> deadlock Fix this by using memalloc_noio_{save,restore}, which sets the GFP_NOIO flag for the current scope when issuing commands/IOs that are expected to clear errors. Cc: <linux-acpi@vger.kernel.org> Cc: <linux-nvdimm@lists.01.org> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Robert Moore <robert.moore@intel.com> Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Vishal Verma <vishal.l.verma@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-08-31libnvdimm, btt: cache sector_size in arena_infoVishal Verma
In preparation for the error clearing rework, add sector_size in the arena_info struct. Signed-off-by: Vishal Verma <vishal.l.verma@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-08-31libnvdimm, btt: ensure that flags were also unchanged during a map_readVishal Verma
In btt_map_read, we read the map twice to make sure that the map entry didn't change after we added it to the read tracking table. In anticipation of expanding the use of the error bit, also make sure that the error and zero flags are constant across the two map reads. Signed-off-by: Vishal Verma <vishal.l.verma@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-08-31libnvdimm, btt: refactor map entry operations with macrosVishal Verma
Add helpers for converting a raw map entry to just the block number, or either of the 'e' or 'z' flags in preparation for actually using the error flag to mark blocks with media errors. Signed-off-by: Vishal Verma <vishal.l.verma@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-08-31libnvdimm, btt: fix a missed NVDIMM_IO_ATOMIC case in the write pathVishal Verma
The IO context conversion for rw_bytes missed a case in the BTT write path (btt_map_write) which should've been marked as atomic. In reality this should not cause a problem, because map writes are to small for nsio_rw_bytes to attempt error clearing, but it should be fixed for posterity. Add a might_sleep() in the non-atomic section of nsio_rw_bytes so that things like the nfit unit tests, which don't actually sleep, can catch bugs like this. Cc: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Vishal Verma <vishal.l.verma@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-08-30libnvdimm, btt: check memory allocation failureChristophe Jaillet
Check memory allocation failures and return -ENOMEM in such cases, as already done few lines below for another memory allocation. This avoids NULL pointers dereference. Cc: <stable@vger.kernel.org> Fixes: 14e494542636 ("libnvdimm, btt: BTT updates for UEFI 2.7 format") Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr> Reviewed-by: Vishal Verma <vishal.l.verma@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-08-29libnvdimm, label: fix index block size calculationDan Williams
The old calculation assumed that the label space was 128k and the label size is 128. With v1.2 labels where the label size is 256 this calculation will return zero. We are saved by the fact that the nsindex_size is always pre-initialized from a previous 128 byte assumption and we are lucky that the index sizes turn out the same. Fix this going forward in case we start encountering different geometries of label areas besides 128k. Since the label size can change from one call to the next, drop the caching of nsindex_size. Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-08-23block: replace bi_bdev with a gendisk pointer and partitions indexChristoph Hellwig
This way we don't need a block_device structure to submit I/O. The block_device has different life time rules from the gendisk and request_queue and is usually only available when the block device node is open. Other callers need to explicitly create one (e.g. the lightnvm passthrough code, or the new nvme multipathing code). For the actual I/O path all that we need is the gendisk, which exists once per block device. But given that the block layer also does partition remapping we additionally need a partition index, which is used for said remapping in generic_make_request. Note that all the block drivers generally want request_queue or sometimes the gendisk, so this removes a layer of indirection all over the stack. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>