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* mm: meminit: make __early_pfn_to_nid SMP-safe and introduce meminit_pfn_in_nidMel Gorman2015-07-014-30/+51
| | | | | | | | | | | | | | | | | | | | | | | | | | | | __early_pfn_to_nid() use static variables to cache recent lookups as memblock lookups are very expensive but it assumes that memory initialisation is single-threaded. Parallel initialisation of struct pages will break that assumption so this patch makes __early_pfn_to_nid() SMP-safe by requiring the caller to cache recent search information. early_pfn_to_nid() keeps the same interface but is only safe to use early in boot due to the use of a global static variable. meminit_pfn_in_nid() is an SMP-safe version that callers must maintain their own state for. Signed-off-by: Mel Gorman <mgorman@suse.de> Tested-by: Nate Zimmer <nzimmer@sgi.com> Tested-by: Waiman Long <waiman.long@hp.com> Tested-by: Daniel J Blueman <daniel@numascale.com> Acked-by: Pekka Enberg <penberg@kernel.org> Cc: Robin Holt <robinmholt@gmail.com> Cc: Nate Zimmer <nzimmer@sgi.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Waiman Long <waiman.long@hp.com> Cc: Scott Norton <scott.norton@hp.com> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: page_alloc: pass PFN to __free_pages_bootmemMel Gorman2015-07-015-11/+14
| | | | | | | | | | | | | | | | | | | | | | | | | __free_pages_bootmem prepares a page for release to the buddy allocator and assumes that the struct page is initialised. Parallel initialisation of struct pages defers initialisation and __free_pages_bootmem can be called for struct pages that cannot yet map struct page to PFN. This patch passes PFN to __free_pages_bootmem with no other functional change. Signed-off-by: Mel Gorman <mgorman@suse.de> Tested-by: Nate Zimmer <nzimmer@sgi.com> Tested-by: Waiman Long <waiman.long@hp.com> Tested-by: Daniel J Blueman <daniel@numascale.com> Acked-by: Pekka Enberg <penberg@kernel.org> Cc: Robin Holt <robinmholt@gmail.com> Cc: Nate Zimmer <nzimmer@sgi.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Waiman Long <waiman.long@hp.com> Cc: Scott Norton <scott.norton@hp.com> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: meminit: only set page reserved in the memblock regionNathan Zimmer2015-07-013-1/+21
| | | | | | | | | | | | | | | | | | | | | | | | | | Currently each page struct is set as reserved upon initialization. This patch leaves the reserved bit clear and only sets the reserved bit when it is known the memory was allocated by the bootmem allocator. This makes it easier to distinguish between uninitialised struct pages and reserved struct pages in later patches. Signed-off-by: Robin Holt <holt@sgi.com> Signed-off-by: Nathan Zimmer <nzimmer@sgi.com> Signed-off-by: Mel Gorman <mgorman@suse.de> Tested-by: Nate Zimmer <nzimmer@sgi.com> Tested-by: Waiman Long <waiman.long@hp.com> Tested-by: Daniel J Blueman <daniel@numascale.com> Acked-by: Pekka Enberg <penberg@kernel.org> Cc: Robin Holt <robinmholt@gmail.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Waiman Long <waiman.long@hp.com> Cc: Scott Norton <scott.norton@hp.com> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: meminit: move page initialization into a separate functionRobin Holt2015-07-011-33/+46
| | | | | | | | | | | | | | | | | | | | | | | | Currently, memmap_init_zone() has all the smarts for initializing a single page. A subset of this is required for parallel page initialisation and so this patch breaks up the monolithic function in preparation. Signed-off-by: Robin Holt <holt@sgi.com> Signed-off-by: Nathan Zimmer <nzimmer@sgi.com> Signed-off-by: Mel Gorman <mgorman@suse.de> Tested-by: Nate Zimmer <nzimmer@sgi.com> Tested-by: Waiman Long <waiman.long@hp.com> Tested-by: Daniel J Blueman <daniel@numascale.com> Acked-by: Pekka Enberg <penberg@kernel.org> Cc: Robin Holt <robinmholt@gmail.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Waiman Long <waiman.long@hp.com> Cc: Scott Norton <scott.norton@hp.com> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* memblock: introduce a for_each_reserved_mem_region iteratorRobin Holt2015-07-012-0/+50
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Struct page initialisation had been identified as one of the reasons why large machines take a long time to boot. Patches were posted a long time ago to defer initialisation until they were first used. This was rejected on the grounds it should not be necessary to hurt the fast paths. This series reuses much of the work from that time but defers the initialisation of memory to kswapd so that one thread per node initialises memory local to that node. After applying the series and setting the appropriate Kconfig variable I see this in the boot log on a 64G machine [ 7.383764] kswapd 0 initialised deferred memory in 188ms [ 7.404253] kswapd 1 initialised deferred memory in 208ms [ 7.411044] kswapd 3 initialised deferred memory in 216ms [ 7.411551] kswapd 2 initialised deferred memory in 216ms On a 1TB machine, I see [ 8.406511] kswapd 3 initialised deferred memory in 1116ms [ 8.428518] kswapd 1 initialised deferred memory in 1140ms [ 8.435977] kswapd 0 initialised deferred memory in 1148ms [ 8.437416] kswapd 2 initialised deferred memory in 1148ms Once booted the machine appears to work as normal. Boot times were measured from the time shutdown was called until ssh was available again. In the 64G case, the boot time savings are negligible. On the 1TB machine, the savings were 16 seconds. Nate Zimmer said: : On an older 8 TB box with lots and lots of cpus the boot time, as : measure from grub to login prompt, the boot time improved from 1484 : seconds to exactly 1000 seconds. Waiman Long said: : I ran a bootup timing test on a 12-TB 16-socket IvyBridge-EX system. From : grub menu to ssh login, the bootup time was 453s before the patch and 265s : after the patch - a saving of 188s (42%). Daniel Blueman said: : On a 7TB, 1728-core NumaConnect system with 108 NUMA nodes, we're seeing : stock 4.0 boot in 7136s. This drops to 2159s, or a 70% reduction with : this patchset. Non-temporal PMD init (https://lkml.org/lkml/2015/4/23/350) : drops this to 1045s. This patch (of 13): As part of initializing struct page's in 2MiB chunks, we noticed that at the end of free_all_bootmem(), there was nothing which had forced the reserved/allocated 4KiB pages to be initialized. This helper function will be used for that expansion. Signed-off-by: Robin Holt <holt@sgi.com> Signed-off-by: Nate Zimmer <nzimmer@sgi.com> Signed-off-by: Mel Gorman <mgorman@suse.de> Tested-by: Nate Zimmer <nzimmer@sgi.com> Tested-by: Waiman Long <waiman.long@hp.com> Tested-by: Daniel J Blueman <daniel@numascale.com> Acked-by: Pekka Enberg <penberg@kernel.org> Cc: Robin Holt <robinmholt@gmail.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Waiman Long <waiman.long@hp.com> Cc: Scott Norton <scott.norton@hp.com> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge tag 'md/4.2' of git://neil.brown.name/mdLinus Torvalds2015-06-295-101/+146
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull md updates from Neil Brown: "A mixed bag - a few bug fixes - some performance improvement that decrease lock contention - some clean-up Nothing major" * tag 'md/4.2' of git://neil.brown.name/md: md: clear Blocked flag on failed devices when array is read-only. md: unlock mddev_lock on an error path. md: clear mddev->private when it has been freed. md: fix a build warning md/raid5: ignore released_stripes check md/raid5: per hash value and exclusive wait_for_stripe md/raid5: split wait_for_stripe and introduce wait_for_quiescent wait: introduce wait_event_exclusive_cmd md: convert to kstrto*() md/raid10: make sync_request_write() call bio_copy_data()
| * md: clear Blocked flag on failed devices when array is read-only.Neil Brown2015-06-251-0/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The Blocked flag indicates that a device has failed but that this fact hasn't been recorded in the metadata yet. Writes to such devices cannot be allowed until the metadata has been updated. On a read-only array, the Blocked flag will never be cleared. This prevents the device being removed from the array. If the metadata is being handled by the kernel (i.e. !mddev->external), then we can be sure that if the array is switch to writable, then a metadata update will happen and will record the failure. So we don't need the flag set. If metadata is externally managed, it is upto the external manager to clear the 'blocked' flag. Reported-by: XiaoNi <xni@redhat.com> Signed-off-by: NeilBrown <neilb@suse.de>
| * md: unlock mddev_lock on an error path.NeilBrown2015-06-251-1/+3
| | | | | | | | | | | | | | | | This error path retuns while still holding the lock - bad. Fixes: 6791875e2e53 ("md: make reconfig_mutex optional for writes to md sysfs files.") Cc: stable@vger.kernel.org (v4.0+) Signed-off-by: NeilBrown <neilb@suse.com>
| * md: clear mddev->private when it has been freed.NeilBrown2015-06-251-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If ->private is set when ->run is called, it is assumed to be a 'config' prepared as part of 'reshape'. So it is important when we free that config, that we also clear ->private. This is not often a problem as the mddev will normally be discarded shortly after the config us freed. However if an 'assemble' races with a final close, the assemble can use the old mddev which has a stale ->private. This leads to any of various sorts of crashes. So clear ->private after calling ->free(). Reported-by: Nate Clark <nate@neworld.us> Cc: stable@vger.kernel.org (v4.0+) Fixes: afa0f557cb15 ("md: rename ->stop to ->free") Signed-off-by: NeilBrown <neilb@suse.com>
| * md: fix a build warningFiro Yang2015-06-171-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Warning like this: drivers/md/md.c: In function "update_array_info": drivers/md/md.c:6394:26: warning: logical not is only applied to the left hand side of comparison [-Wlogical-not-parentheses] !mddev->persistent != info->not_persistent|| Fix it as Neil Brown said: mddev->persistent != !info->not_persistent || Signed-off-by: Firo Yang <firogm@gmail.com> Signed-off-by: NeilBrown <neilb@suse.de>
| * md/raid5: ignore released_stripes checkShaohua Li2015-06-171-2/+2
| | | | | | | | | | | | | | | | | | conf->released_stripes list isn't always related to where there are free stripes pending. Active stripes can be in the list too. And even free stripes were active very recently. Signed-off-by: Shaohua Li <shli@fb.com> Signed-off-by: NeilBrown <neilb@suse.de>
| * md/raid5: per hash value and exclusive wait_for_stripeYuanhan Liu2015-06-172-9/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | I noticed heavy spin lock contention at get_active_stripe() with fsmark multiple thread write workloads. Here is how this hot contention comes from. We have limited stripes, and it's a multiple thread write workload. Hence, those stripes will be taken soon, which puts later processes to sleep for waiting free stripes. When enough stripes(>= 1/4 total stripes) are released, all process are woken, trying to get the lock. But there is one only being able to get this lock for each hash lock, making other processes spinning out there for acquiring the lock. Thus, it's effectiveless to wakeup all processes and let them battle for a lock that permits one to access only each time. Instead, we could make it be a exclusive wake up: wake up one process only. That avoids the heavy spin lock contention naturally. To do the exclusive wake up, we've to split wait_for_stripe into multiple wait queues, to make it per hash value, just like the hash lock. Here are some test results I have got with this patch applied(all test run 3 times): `fsmark.files_per_sec' ===================== next-20150317 this patch ------------------------- ------------------------- metric_value ±stddev metric_value ±stddev change testbox/benchmark/testcase-params ------------------------- ------------------------- -------- ------------------------------ 25.600 ±0.0 92.700 ±2.5 262.1% ivb44/fsmark/1x-64t-4BRD_12G-RAID5-btrfs-4M-30G-fsyncBeforeClose 25.600 ±0.0 77.800 ±0.6 203.9% ivb44/fsmark/1x-64t-9BRD_6G-RAID5-btrfs-4M-30G-fsyncBeforeClose 32.000 ±0.0 93.800 ±1.7 193.1% ivb44/fsmark/1x-64t-4BRD_12G-RAID5-ext4-4M-30G-fsyncBeforeClose 32.000 ±0.0 81.233 ±1.7 153.9% ivb44/fsmark/1x-64t-9BRD_6G-RAID5-ext4-4M-30G-fsyncBeforeClose 48.800 ±14.5 99.667 ±2.0 104.2% ivb44/fsmark/1x-64t-4BRD_12G-RAID5-xfs-4M-30G-fsyncBeforeClose 6.400 ±0.0 12.800 ±0.0 100.0% ivb44/fsmark/1x-64t-3HDD-RAID5-btrfs-4M-40G-fsyncBeforeClose 63.133 ±8.2 82.800 ±0.7 31.2% ivb44/fsmark/1x-64t-9BRD_6G-RAID5-xfs-4M-30G-fsyncBeforeClose 245.067 ±0.7 306.567 ±7.9 25.1% ivb44/fsmark/1x-64t-4BRD_12G-RAID5-f2fs-4M-30G-fsyncBeforeClose 17.533 ±0.3 21.000 ±0.8 19.8% ivb44/fsmark/1x-1t-3HDD-RAID5-xfs-4M-40G-fsyncBeforeClose 188.167 ±1.9 215.033 ±3.1 14.3% ivb44/fsmark/1x-1t-4BRD_12G-RAID5-btrfs-4M-30G-NoSync 254.500 ±1.8 290.733 ±2.4 14.2% ivb44/fsmark/1x-1t-9BRD_6G-RAID5-btrfs-4M-30G-NoSync `time.system_time' ===================== next-20150317 this patch ------------------------- ------------------------- metric_value ±stddev metric_value ±stddev change testbox/benchmark/testcase-params ------------------------- ------------------------- -------- ------------------------------ 7235.603 ±1.2 185.163 ±1.9 -97.4% ivb44/fsmark/1x-64t-4BRD_12G-RAID5-btrfs-4M-30G-fsyncBeforeClose 7666.883 ±2.9 202.750 ±1.0 -97.4% ivb44/fsmark/1x-64t-9BRD_6G-RAID5-btrfs-4M-30G-fsyncBeforeClose 14567.893 ±0.7 421.230 ±0.4 -97.1% ivb44/fsmark/1x-64t-3HDD-RAID5-btrfs-4M-40G-fsyncBeforeClose 3697.667 ±14.0 148.190 ±1.7 -96.0% ivb44/fsmark/1x-64t-4BRD_12G-RAID5-xfs-4M-30G-fsyncBeforeClose 5572.867 ±3.8 310.717 ±1.4 -94.4% ivb44/fsmark/1x-64t-9BRD_6G-RAID5-ext4-4M-30G-fsyncBeforeClose 5565.050 ±0.5 313.277 ±1.5 -94.4% ivb44/fsmark/1x-64t-4BRD_12G-RAID5-ext4-4M-30G-fsyncBeforeClose 2420.707 ±17.1 171.043 ±2.7 -92.9% ivb44/fsmark/1x-64t-9BRD_6G-RAID5-xfs-4M-30G-fsyncBeforeClose 3743.300 ±4.6 379.827 ±3.5 -89.9% ivb44/fsmark/1x-64t-3HDD-RAID5-ext4-4M-40G-fsyncBeforeClose 3308.687 ±6.3 363.050 ±2.0 -89.0% ivb44/fsmark/1x-64t-3HDD-RAID5-xfs-4M-40G-fsyncBeforeClose Where, 1x: where 'x' means iterations or loop, corresponding to the 'L' option of fsmark 1t, 64t: where 't' means thread 4M: means the single file size, corresponding to the '-s' option of fsmark 40G, 30G, 120G: means the total test size 4BRD_12G: BRD is the ramdisk, where '4' means 4 ramdisk, and where '12G' means the size of one ramdisk. So, it would be 48G in total. And we made a raid on those ramdisk As you can see, though there are no much performance gain for hard disk workload, the system time is dropped heavily, up to 97%. And as expected, the performance increased a lot, up to 260%, for fast device(ram disk). v2: use bits instead of array to note down wait queue need to wake up. Signed-off-by: Yuanhan Liu <yuanhan.liu@linux.intel.com> Signed-off-by: NeilBrown <neilb@suse.de>
| * md/raid5: split wait_for_stripe and introduce wait_for_quiescentYuanhan Liu2015-06-172-6/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | I noticed heavy spin lock contention at get_active_stripe(), introduced at being wake up stage, where a bunch of processes try to re-hold the spin lock again. After giving some thoughts on this issue, I found the lock could be relieved(and even avoided) if we turn the wait_for_stripe to per waitqueue for each lock hash and make the wake up exclusive: wake up one process each time, which avoids the lock contention naturally. Before go hacking with wait_for_stripe, I found it actually has 2 usages: for the array to enter or leave the quiescent state, and also to wait for an available stripe in each of the hash lists. So this patch splits the first usage off into a separate wait_queue, wait_for_quiescent, and the next patch will turn the second usage into one waitqueue for each hash value, and make it exclusive, to relieve the lock contention. v2: wake_up(wait_for_quiescent) when (active_stripes == 0) Commit log refactor suggestion from Neil. Signed-off-by: Yuanhan Liu <yuanhan.liu@linux.intel.com> Signed-off-by: NeilBrown <neilb@suse.de>
| * wait: introduce wait_event_exclusive_cmdYuanhan Liu2015-06-171-0/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | It's just a variant of wait_event_cmd(), with exclusive flag being set. For cases like RAID5, which puts many processes to sleep until 1/4 resources are free, a wake_up wakes up all processes to run, but there is one process being able to get the resource as it's protected by a spin lock. That ends up introducing heavy lock contentions, and hurts performance badly. Here introduce wait_event_exclusive_cmd to relieve the lock contention naturally by letting wake_up just wake up one process. Cc: Ingo Molnar <mingo@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> v2: its assumed that wait*() and __wait*() have the same arguments - peterz Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Yuanhan Liu <yuanhan.liu@linux.intel.com> Signed-off-by: NeilBrown <neilb@suse.de>
| * md: convert to kstrto*()Alexey Dobriyan2015-06-171-68/+81
| | | | | | | | | | | | | | | | | | Convert away from deprecated simple_strto*() functions. Add "fit into sector_t" checks. Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: NeilBrown <neilb@suse.de>
| * md/raid10: make sync_request_write() call bio_copy_data()Kent Overstreet2015-06-171-14/+4Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Refactor sync_request_write() of md/raid10 to use bio_copy_data() instead of open coding bio_vec iterations. Cc: Christoph Hellwig <hch@infradead.org> Cc: Neil Brown <neilb@suse.de> Cc: linux-raid@vger.kernel.org Reviewed-by: Christoph Hellwig <hch@lst.de> Acked-by: NeilBrown <neilb@suse.de> Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com> [dpark: add more description in commit message] Signed-off-by: Dongsu Park <dpark@posteo.net> Signed-off-by: Ming Lin <mlin@kernel.org> Signed-off-by: NeilBrown <neilb@suse.de>
* | Fix kmalloc slab creation sequenceChristoph Lameter2015-06-292-38/+16Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch restores the slab creation sequence that was broken by commit 4066c33d0308f8 and also reverts the portions that introduced the KMALLOC_LOOP_XXX macros. Those can never really work since the slab creation is much more complex than just going from a minimum to a maximum number. The latest upstream kernel boots cleanly on my machine with a 64 bit x86 configuration under KVM using either SLAB or SLUB. Fixes: 4066c33d0308f8 ("support the slub_debug boot option") Reported-by: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Christoph Lameter <cl@linux.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | Merge tag 'libnvdimm-for-4.2' of ↵Linus Torvalds2015-06-2957-155/+13842
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/djbw/nvdimm Pull libnvdimm subsystem from Dan Williams: "The libnvdimm sub-system introduces, in addition to the libnvdimm-core, 4 drivers / enabling modules: NFIT: Instantiates an "nvdimm bus" with the core and registers memory devices (NVDIMMs) enumerated by the ACPI 6.0 NFIT (NVDIMM Firmware Interface table). After registering NVDIMMs the NFIT driver then registers "region" devices. A libnvdimm-region defines an access mode and the boundaries of persistent memory media. A region may span multiple NVDIMMs that are interleaved by the hardware memory controller. In turn, a libnvdimm-region can be carved into a "namespace" device and bound to the PMEM or BLK driver which will attach a Linux block device (disk) interface to the memory. PMEM: Initially merged in v4.1 this driver for contiguous spans of persistent memory address ranges is re-worked to drive PMEM-namespaces emitted by the libnvdimm-core. In this update the PMEM driver, on x86, gains the ability to assert that writes to persistent memory have been flushed all the way through the caches and buffers in the platform to persistent media. See memcpy_to_pmem() and wmb_pmem(). BLK: This new driver enables access to persistent memory media through "Block Data Windows" as defined by the NFIT. The primary difference of this driver to PMEM is that only a small window of persistent memory is mapped into system address space at any given point in time. Per-NVDIMM windows are reprogrammed at run time, per-I/O, to access different portions of the media. BLK-mode, by definition, does not support DAX. BTT: This is a library, optionally consumed by either PMEM or BLK, that converts a byte-accessible namespace into a disk with atomic sector update semantics (prevents sector tearing on crash or power loss). The sinister aspect of sector tearing is that most applications do not know they have a atomic sector dependency. At least today's disk's rarely ever tear sectors and if they do one almost certainly gets a CRC error on access. NVDIMMs will always tear and always silently. Until an application is audited to be robust in the presence of sector-tearing the usage of BTT is recommended. Thanks to: Ross Zwisler, Jeff Moyer, Vishal Verma, Christoph Hellwig, Ingo Molnar, Neil Brown, Boaz Harrosh, Robert Elliott, Matthew Wilcox, Andy Rudoff, Linda Knippers, Toshi Kani, Nicholas Moulin, Rafael Wysocki, and Bob Moore" * tag 'libnvdimm-for-4.2' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/nvdimm: (33 commits) arch, x86: pmem api for ensuring durability of persistent memory updates libnvdimm: Add sysfs numa_node to NVDIMM devices libnvdimm: Set numa_node to NVDIMM devices acpi: Add acpi_map_pxm_to_online_node() libnvdimm, nfit: handle unarmed dimms, mark namespaces read-only pmem: flag pmem block devices as non-rotational libnvdimm: enable iostat pmem: make_request cleanups libnvdimm, pmem: fix up max_hw_sectors libnvdimm, blk: add support for blk integrity libnvdimm, btt: add support for blk integrity fs/block_dev.c: skip rw_page if bdev has integrity libnvdimm: Non-Volatile Devices tools/testing/nvdimm: libnvdimm unit test infrastructure libnvdimm, nfit, nd_blk: driver for BLK-mode access persistent memory nd_btt: atomic sector updates libnvdimm: infrastructure for btt devices libnvdimm: write blk label set libnvdimm: write pmem label set libnvdimm: blk labels and namespace instantiation ...
| * | arch, x86: pmem api for ensuring durability of persistent memory updatesRoss Zwisler2015-06-267-13/+257
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Based on an original patch by Ross Zwisler [1]. Writes to persistent memory have the potential to be posted to cpu cache, cpu write buffers, and platform write buffers (memory controller) before being committed to persistent media. Provide apis, memcpy_to_pmem(), wmb_pmem(), and memremap_pmem(), to write data to pmem and assert that it is durable in PMEM (a persistent linear address range). A '__pmem' attribute is added so sparse can track proper usage of pointers to pmem. This continues the status quo of pmem being x86 only for 4.2, but reworks to ioremap, and wider implementation of memremap() will enable other archs in 4.3. [1]: https://lists.01.org/pipermail/linux-nvdimm/2015-May/000932.html Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com> [djbw: various reworks] Signed-off-by: Dan Williams <dan.j.williams@intel.com>
| * | libnvdimm: Add sysfs numa_node to NVDIMM devicesToshi Kani2015-06-265-0/+34
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * | libnvdimm: Set numa_node to NVDIMM devicesToshi Kani2015-06-266-1/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * | acpi: Add acpi_map_pxm_to_online_node()Toshi Kani2015-06-262-3/+52
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The kernel initializes CPU & memory's NUMA topology from ACPI SRAT table. Some other ACPI tables, such as NFIT and DMAR, also contain proximity IDs for their device's NUMA topology. This information can be used to improve performance of these devices. This patch introduces acpi_map_pxm_to_online_node(), which is similar to acpi_map_pxm_to_node(), but always returns an online node. When the mapped node from a given proximity ID is offline, it looks up the node distance table and returns the nearest online node. ACPI device drivers, which are called after the NUMA initialization has completed in the kernel, can call this interface to obtain their device NUMA topology from ACPI tables. Such drivers do not have to deal with offline nodes. A node may be offline when a device proximity ID is unique, SRAT memory entry does not exist, or NUMA is disabled, ex. "numa=off" on x86. This patch also moves the pxm range check from acpi_get_node() to acpi_map_pxm_to_node(). Signed-off-by: Toshi Kani <toshi.kani@hp.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
| * | libnvdimm, nfit: handle unarmed dimms, mark namespaces read-onlyDan Williams2015-06-2610-3/+100
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * | pmem: flag pmem block devices as non-rotationalDan Williams2015-06-261-0/+1
| | | | | | | | | | | | | | | | | | | | | ...since they are effectively SSDs as far as userspace is concerned. Reviewed-by: Vishal Verma <vishal.l.verma@linux.intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
| * | libnvdimm: enable iostatDan Williams2015-06-265-2/+59
| | | | | | | | | | | | | | | | | | | | | | | | This is disabled by default as the overhead is prohibitive, but if the user takes the action to turn it on we'll oblige. Reviewed-by: Vishal Verma <vishal.l.verma@linux.intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
| * | pmem: make_request cleanupsDan Williams2015-06-261-21/+5Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Various cleanups: 1/ Kill the BUG_ON since we've already told the block layer we don't support DISCARD on all these drivers. 2/ Kill the 'rw' variable, no need to cache it. 3/ Kill the local 'sector' variable. bio_for_each_segment() is already advancing the iterator's sector number by the bio_vec length. 4/ Kill the check for accessing past the end of device generic_make_request_checks() already does that. Suggested-by: Christoph Hellwig <hch@lst.de> [hch: kill access past end of the device check] Reviewed-by: Vishal Verma <vishal.l.verma@linux.intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
| * | libnvdimm, pmem: fix up max_hw_sectorsDan Williams2015-06-261-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | There is no hardware limit to enforce on the size of the i/o that can be passed to an nvdimm block device, so set it to UINT_MAX. Reviewed-by: Vishal Verma <vishal.l.verma@linux.intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
| * | libnvdimm, blk: add support for blk integrityVishal Verma2015-06-265-23/+159
| | | | | | | | | | | | | | | | | | | | | | | | Support multiple block sizes (sector + metadata) for nd_blk in the same way as done for the BTT. Add the idea of an 'internal' lbasize, which is properly aligned and padded, and store metadata in this space. Signed-off-by: Vishal Verma <vishal.l.verma@linux.intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
| * | libnvdimm, btt: add support for blk integrityVishal Verma2015-06-265-18/+154
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Support multiple block sizes (sector + metadata) using the blk integrity framework. This registers a new integrity template that defines the protection information tuple size based on the configured metadata size, and simply acts as a passthrough for protection information generated by another layer. The metadata is written to the storage as-is, and read back with each sector. Signed-off-by: Vishal Verma <vishal.l.verma@linux.intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
| * | fs/block_dev.c: skip rw_page if bdev has integrityVishal Verma2015-06-261-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If a block device has bio integrity enabled, rw_page will bypass the integrity payload, which is undesirable. Skip rw_page if this is the case. Currently brd and zram provide rw_page, and the proposed 'nd' drivers will too. Cc: Jens Axboe <axboe@fb.com> Cc: Martin K. Petersen <martin.petersen@oracle.com> Suggested-by: Matthew Wilcox <matthew.r.wilcox@intel.com> Signed-off-by: Vishal Verma <vishal.l.verma@linux.intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
| * | libnvdimm: Non-Volatile DevicesDan Williams2015-06-263-13/+858
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Maintainer information and documentation for drivers/nvdimm Cc: Andy Lutomirski <luto@amacapital.net> Cc: Boaz Harrosh <boaz@plexistor.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Jens Axboe <axboe@fb.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Christoph Hellwig <hch@lst.de> Cc: Neil Brown <neilb@suse.de> Cc: Greg KH <gregkh@linuxfoundation.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
| * | tools/testing/nvdimm: libnvdimm unit test infrastructureDan Williams2015-06-269-4/+1377
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 'libnvdimm' is the first driver sub-system in the kernel to implement mocking for unit test coverage. The nfit_test module gets built as an external module and arranges for external module replacements of nfit, libnvdimm, nd_pmem, and nd_blk. These replacements use the linker --wrap option to redirect calls to ioremap() + request_mem_region() to custom defined unit test resources. The end result is a fully functional nvdimm_bus, as far as userspace is concerned, but with the capability to perform otherwise destructive tests on emulated resources. Q: Why not use QEMU for this emulation? QEMU is not suitable for unit testing. QEMU's role is to faithfully emulate the platform. A unit test's role is to unfaithfully implement the platform with the goal of triggering bugs in the corners of the sub-system implementation. As bugs are discovered in platforms, or the sub-system itself, the unit tests are extended to backstop a fix with a reproducer unit test. Another problem with QEMU is that it would require coordination of 3 software projects instead of 2 (kernel + libndctl [1]) to maintain and execute the tests. The chances for bit rot and the difficulty of getting the tests running goes up non-linearly the more components involved. Q: Why submit this to the kernel tree instead of external modules in libndctl? Simple, to alleviate the same risk that out-of-tree external modules face. Updates to drivers/nvdimm/ can be immediately evaluated to see if they have any impact on tools/testing/nvdimm/. Q: What are the negative implications of merging this? It is a unique maintenance burden because the purpose of mocking an interface to enable a unit test is to purposefully short circuit the semantics of a routine to enable testing. For example __wrap_ioremap_cache() fakes the pmem driver into "ioremap()'ing" a test resource buffer allocated by dma_alloc_coherent(). The future maintenance burden hits when someone changes the semantics of ioremap_cache() and wonders what the implications are for the unit test. [1]: https://github.com/pmem/ndctl Cc: <linux-acpi@vger.kernel.org> Cc: Lv Zheng <lv.zheng@intel.com> Cc: Robert Moore <robert.moore@intel.com> Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
| * | libnvdimm, nfit, nd_blk: driver for BLK-mode access persistent memoryRoss Zwisler2015-06-2612-34/+941
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The libnvdimm implementation handles allocating dimm address space (DPA) between PMEM and BLK mode interfaces. After DPA has been allocated from a BLK-region to a BLK-namespace the nd_blk driver attaches to handle I/O as a struct bio based block device. Unlike PMEM, BLK is required to handle platform specific details like mmio register formats and memory controller interleave. For this reason the libnvdimm generic nd_blk driver calls back into the bus provider to carry out the I/O. This initial implementation handles the BLK interface defined by the ACPI 6 NFIT [1] and the NVDIMM DSM Interface Example [2] composed from DCR (dimm control region), BDW (block data window), IDT (interleave descriptor) NFIT structures and the hardware register format. [1]: http://www.uefi.org/sites/default/files/resources/ACPI_6.0.pdf [2]: http://pmem.io/documents/NVDIMM_DSM_Interface_Example.pdf Cc: Andy Lutomirski <luto@amacapital.net> Cc: Boaz Harrosh <boaz@plexistor.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Jens Axboe <axboe@fb.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
| * | nd_btt: atomic sector updatesVishal Verma2015-06-2613-25/+1950
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | BTT stands for Block Translation Table, and is a way to provide power fail sector atomicity semantics for block devices that have the ability to perform byte granularity IO. It relies on the capability of libnvdimm namespace devices to do byte aligned IO. The BTT works as a stacked blocked device, and reserves a chunk of space from the backing device for its accounting metadata. It is a bio-based driver because all IO is done synchronously, and there is no queuing or asynchronous completions at either the device or the driver level. The BTT uses 'lanes' to index into various 'on-disk' data structures, and lanes also act as a synchronization mechanism in case there are more CPUs than available lanes. We did a comparison between two lane lock strategies - first where we kept an atomic counter around that tracked which was the last lane that was used, and 'our' lane was determined by atomically incrementing that. That way, for the nr_cpus > nr_lanes case, theoretically, no CPU would be blocked waiting for a lane. The other strategy was to use the cpu number we're scheduled on to and hash it to a lane number. Theoretically, this could block an IO that could've otherwise run using a different, free lane. But some fio workloads showed that the direct cpu -> lane hash performed faster than tracking 'last lane' - my reasoning is the cache thrash caused by moving the atomic variable made that approach slower than simply waiting out the in-progress IO. This supports the conclusion that the driver can be a very simple bio-based one that does synchronous IOs instead of queuing. Cc: Andy Lutomirski <luto@amacapital.net> Cc: Boaz Harrosh <boaz@plexistor.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Jens Axboe <axboe@fb.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Christoph Hellwig <hch@lst.de> Cc: Neil Brown <neilb@suse.de> Cc: Jeff Moyer <jmoyer@redhat.com> Cc: Dave Chinner <david@fromorbit.com> Cc: Greg KH <gregkh@linuxfoundation.org> [jmoyer: fix nmi watchdog timeout in btt_map_init] [jmoyer: move btt initialization to module load path] [jmoyer: fix memory leak in the btt initialization path] [jmoyer: Don't overwrite corrupted arenas] Signed-off-by: Vishal Verma <vishal.l.verma@linux.intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
| * | libnvdimm: infrastructure for btt devicesDan Williams2015-06-2513-99/+879
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * | libnvdimm: write blk label setDan Williams2015-06-256-24/+369
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * | libnvdimm: write pmem label setDan Williams2015-06-255-14/+455
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | After 'uuid', 'size', and optionally 'alt_name' have been set to valid values the labels on the dimms can be updated. Write procedure is: 1/ Allocate and write new labels in the "next" index 2/ Free the old labels in the working copy 3/ Write the bitmap and the label space on the dimm 4/ Write the index to make the update valid Label ranges directly mirror the dpa resource values for the given label_id of the namespace. 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>
| * | libnvdimm: blk labels and namespace instantiationDan Williams2015-06-258-38/+594
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A blk label set describes a namespace comprised of one or more discontiguous dpa ranges on a single dimm. They may alias with one or more pmem interleave sets that include the given dimm. This is the runtime/volatile configuration infrastructure for sysfs manipulation of 'alt_name', 'uuid', 'size', and 'sector_size'. A later patch will make these settings persistent by writing back the label(s). Unlike pmem namespaces, multiple blk namespaces can be created per region. Once a blk namespace has been created a new seed device (unconfigured child of a parent blk region) is instantiated. As long as a region has 'available_size' != 0 new child namespaces may be created. 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>
| * | libnvdimm: pmem label sets and namespace instantiation.Dan Williams2015-06-2515-31/+1506
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * | libnvdimm: namespace indices: read and validateDan Williams2015-06-257-2/+520
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This on media label format [1] consists of two index blocks followed by an array of labels. None of these structures are ever updated in place. A sequence number tracks the current active index and the next one to write, while labels are written to free slots. +------------+ | | | nsindex0 | | | +------------+ | | | nsindex1 | | | +------------+ | label0 | +------------+ | label1 | +------------+ | | ....nslot... | | +------------+ | labelN | +------------+ After reading valid labels, store the dpa ranges they claim into per-dimm resource trees. [1]: http://pmem.io/documents/NVDIMM_Namespace_Spec.pdf Cc: Neil Brown <neilb@suse.de> Acked-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
| * | libnvdimm, nfit: add interleave-set state-tracking infrastructureDan Williams2015-06-258-5/+269
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * | libnvdimm, pmem: add libnvdimm support to the pmem driverDan Williams2015-06-253-67/+96
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | nd_pmem attaches to persistent memory regions and namespaces emitted by the libnvdimm subsystem, and, same as the original pmem driver, presents the system-physical-address range as a block device. The existing e820-type-12 to pmem setup is converted to an nvdimm_bus that emits an nd_namespace_io device. Note that the X in 'pmemX' is now derived from the parent region. This provides some stability to the pmem devices names from boot-to-boot. The minor numbers are also more predictable by passing 0 to alloc_disk(). Cc: Andy Lutomirski <luto@amacapital.net> Cc: Boaz Harrosh <boaz@plexistor.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Jens Axboe <axboe@fb.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com> 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>
| * | libnvdimm, pmem: move pmem to drivers/nvdimm/Dan Williams2015-06-255-13/+25
| | | | | | | | | | | | | | | | | | | | | | | | | | | Prepare the pmem driver to consume PMEM namespaces emitted by regions of an nvdimm_bus instance. No functional change. 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>
| * | libnvdimm: support for legacy (non-aliasing) nvdimmsDan Williams2015-06-2513-8/+383
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * | libnvdimm, nfit: regions (block-data-window, persistent memory, volatile memory)Dan Williams2015-06-256-1/+484
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A "region" device represents the maximum capacity of a BLK range (mmio block-data-window(s)), or a PMEM range (DAX-capable persistent memory or volatile memory), without regard for aliasing. Aliasing, in the dimm-local address space (DPA), is resolved by metadata on a dimm to designate which exclusive interface will access the aliased DPA ranges. Support for the per-dimm metadata/label arrvies is in a subsequent patch. The name format of "region" devices is "regionN" where, like dimms, N is a global ida index assigned at discovery time. This id is not reliable across reboots nor in the presence of hotplug. Look to attributes of the region or static id-data of the sub-namespace to generate a persistent name. However, if the platform configuration does not change it is reasonable to expect the same region id to be assigned at the next boot. "region"s have 2 generic attributes "size", and "mapping"s where: - size: the BLK accessible capacity or the span of the system physical address range in the case of PMEM. - mappingN: a tuple describing a dimm's contribution to the region's capacity in the format (<nmemX>,<dpa>,<size>). For a PMEM-region there will be at least one mapping per dimm in the interleave set. For a BLK-region there is only "mapping0" listing the starting DPA of the BLK-region and the available DPA capacity of that space (matches "size" above). The max number of mappings per "region" is hard coded per the constraints of sysfs attribute groups. That said the number of mappings per region should never exceed the maximum number of possible dimms in the system. If the current number turns out to not be enough then the "mappings" attribute clarifies how many there are supposed to be. "32 should be enough for anybody...". 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>
| * | libnvdimm, nvdimm: dimm driver and base libnvdimm device-driver infrastructureDan Williams2015-06-2511-15/+527
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * 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>
| * | libnvdimm: control (ioctl) messages for nvdimm_bus and nvdimm devicesDan Williams2015-06-2510-10/+810
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * | libnvdimm, nfit: dimm/memory-devicesDan Williams2015-06-258-4/+321
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * | libnvdimm: control character device and nvdimm_bus sysfs attributesDan Williams2015-06-257-3/+215
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * | libnvdimm, nfit: initial libnvdimm infrastructure and NFIT supportDan Williams2015-06-2511-0/+733
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A struct nvdimm_bus is the anchor device for registering nvdimm resources and interfaces, for example, a character control device, nvdimm devices, and I/O region devices. The ACPI NFIT (NVDIMM Firmware Interface Table) is one possible platform description for such non-volatile memory resources in a system. The nfit.ko driver attaches to the "ACPI0012" device that indicates the presence of the NFIT and parses the table to register a struct nvdimm_bus instance. Cc: <linux-acpi@vger.kernel.org> Cc: Lv Zheng <lv.zheng@intel.com> Cc: Robert Moore <robert.moore@intel.com> Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Jeff Moyer <jmoyer@redhat.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>