summaryrefslogtreecommitdiff
path: root/Documentation/admin-guide/blockdev
AgeCommit message (Collapse)Author
2025-05-31Merge tag 'mm-stable-2025-05-31-14-50' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: - "Add folio_mk_pte()" from Matthew Wilcox simplifies the act of creating a pte which addresses the first page in a folio and reduces the amount of plumbing which architecture must implement to provide this. - "Misc folio patches for 6.16" from Matthew Wilcox is a shower of largely unrelated folio infrastructure changes which clean things up and better prepare us for future work. - "memory,x86,acpi: hotplug memory alignment advisement" from Gregory Price adds early-init code to prevent x86 from leaving physical memory unused when physical address regions are not aligned to memory block size. - "mm/compaction: allow more aggressive proactive compaction" from Michal Clapinski provides some tuning of the (sadly, hard-coded (more sadly, not auto-tuned)) thresholds for our invokation of proactive compaction. In a simple test case, the reduction of a guest VM's memory consumption was dramatic. - "Minor cleanups and improvements to swap freeing code" from Kemeng Shi provides some code cleaups and a small efficiency improvement to this part of our swap handling code. - "ptrace: introduce PTRACE_SET_SYSCALL_INFO API" from Dmitry Levin adds the ability for a ptracer to modify syscalls arguments. At this time we can alter only "system call information that are used by strace system call tampering, namely, syscall number, syscall arguments, and syscall return value. This series should have been incorporated into mm.git's "non-MM" branch, but I goofed. - "fs/proc: extend the PAGEMAP_SCAN ioctl to report guard regions" from Andrei Vagin extends the info returned by the PAGEMAP_SCAN ioctl against /proc/pid/pagemap. This permits CRIU to more efficiently get at the info about guard regions. - "Fix parameter passed to page_mapcount_is_type()" from Gavin Shan implements that fix. No runtime effect is expected because validate_page_before_insert() happens to fix up this error. - "kernel/events/uprobes: uprobe_write_opcode() rewrite" from David Hildenbrand basically brings uprobe text poking into the current decade. Remove a bunch of hand-rolled implementation in favor of using more current facilities. - "mm/ptdump: Drop assumption that pxd_val() is u64" from Anshuman Khandual provides enhancements and generalizations to the pte dumping code. This might be needed when 128-bit Page Table Descriptors are enabled for ARM. - "Always call constructor for kernel page tables" from Kevin Brodsky ensures that the ctor/dtor is always called for kernel pgtables, as it already is for user pgtables. This permits the addition of more functionality such as "insert hooks to protect page tables". This change does result in various architectures performing unnecesary work, but this is fixed up where it is anticipated to occur. - "Rust support for mm_struct, vm_area_struct, and mmap" from Alice Ryhl adds plumbing to permit Rust access to core MM structures. - "fix incorrectly disallowed anonymous VMA merges" from Lorenzo Stoakes takes advantage of some VMA merging opportunities which we've been missing for 15 years. - "mm/madvise: batch tlb flushes for MADV_DONTNEED and MADV_FREE" from SeongJae Park optimizes process_madvise()'s TLB flushing. Instead of flushing each address range in the provided iovec, we batch the flushing across all the iovec entries. The syscall's cost was approximately halved with a microbenchmark which was designed to load this particular operation. - "Track node vacancy to reduce worst case allocation counts" from Sidhartha Kumar makes the maple tree smarter about its node preallocation. stress-ng mmap performance increased by single-digit percentages and the amount of unnecessarily preallocated memory was dramaticelly reduced. - "mm/gup: Minor fix, cleanup and improvements" from Baoquan He removes a few unnecessary things which Baoquan noted when reading the code. - ""Enhance sysfs handling for memory hotplug in weighted interleave" from Rakie Kim "enhances the weighted interleave policy in the memory management subsystem by improving sysfs handling, fixing memory leaks, and introducing dynamic sysfs updates for memory hotplug support". Fixes things on error paths which we are unlikely to hit. - "mm/damon: auto-tune DAMOS for NUMA setups including tiered memory" from SeongJae Park introduces new DAMOS quota goal metrics which eliminate the manual tuning which is required when utilizing DAMON for memory tiering. - "mm/vmalloc.c: code cleanup and improvements" from Baoquan He provides cleanups and small efficiency improvements which Baoquan found via code inspection. - "vmscan: enforce mems_effective during demotion" from Gregory Price changes reclaim to respect cpuset.mems_effective during demotion when possible. because presently, reclaim explicitly ignores cpuset.mems_effective when demoting, which may cause the cpuset settings to violated. This is useful for isolating workloads on a multi-tenant system from certain classes of memory more consistently. - "Clean up split_huge_pmd_locked() and remove unnecessary folio pointers" from Gavin Guo provides minor cleanups and efficiency gains in in the huge page splitting and migrating code. - "Use kmem_cache for memcg alloc" from Huan Yang creates a slab cache for `struct mem_cgroup', yielding improved memory utilization. - "add max arg to swappiness in memory.reclaim and lru_gen" from Zhongkun He adds a new "max" argument to the "swappiness=" argument for memory.reclaim MGLRU's lru_gen. This directs proactive reclaim to reclaim from only anon folios rather than file-backed folios. - "kexec: introduce Kexec HandOver (KHO)" from Mike Rapoport is the first step on the path to permitting the kernel to maintain existing VMs while replacing the host kernel via file-based kexec. At this time only memblock's reserve_mem is preserved. - "mm: Introduce for_each_valid_pfn()" from David Woodhouse provides and uses a smarter way of looping over a pfn range. By skipping ranges of invalid pfns. - "sched/numa: Skip VMA scanning on memory pinned to one NUMA node via cpuset.mems" from Libo Chen removes a lot of pointless VMA scanning when a task is pinned a single NUMA mode. Dramatic performance benefits were seen in some real world cases. - "JFS: Implement migrate_folio for jfs_metapage_aops" from Shivank Garg addresses a warning which occurs during memory compaction when using JFS. - "move all VMA allocation, freeing and duplication logic to mm" from Lorenzo Stoakes moves some VMA code from kernel/fork.c into the more appropriate mm/vma.c. - "mm, swap: clean up swap cache mapping helper" from Kairui Song provides code consolidation and cleanups related to the folio_index() function. - "mm/gup: Cleanup memfd_pin_folios()" from Vishal Moola does that. - "memcg: Fix test_memcg_min/low test failures" from Waiman Long addresses some bogus failures which are being reported by the test_memcontrol selftest. - "eliminate mmap() retry merge, add .mmap_prepare hook" from Lorenzo Stoakes commences the deprecation of file_operations.mmap() in favor of the new file_operations.mmap_prepare(). The latter is more restrictive and prevents drivers from messing with things in ways which, amongst other problems, may defeat VMA merging. - "memcg: decouple memcg and objcg stocks"" from Shakeel Butt decouples the per-cpu memcg charge cache from the objcg's one. This is a step along the way to making memcg and objcg charging NMI-safe, which is a BPF requirement. - "mm/damon: minor fixups and improvements for code, tests, and documents" from SeongJae Park is yet another batch of miscellaneous DAMON changes. Fix and improve minor problems in code, tests and documents. - "memcg: make memcg stats irq safe" from Shakeel Butt converts memcg stats to be irq safe. Another step along the way to making memcg charging and stats updates NMI-safe, a BPF requirement. - "Let unmap_hugepage_range() and several related functions take folio instead of page" from Fan Ni provides folio conversions in the hugetlb code. * tag 'mm-stable-2025-05-31-14-50' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (285 commits) mm: pcp: increase pcp->free_count threshold to trigger free_high mm/hugetlb: convert use of struct page to folio in __unmap_hugepage_range() mm/hugetlb: refactor __unmap_hugepage_range() to take folio instead of page mm/hugetlb: refactor unmap_hugepage_range() to take folio instead of page mm/hugetlb: pass folio instead of page to unmap_ref_private() memcg: objcg stock trylock without irq disabling memcg: no stock lock for cpu hot-unplug memcg: make __mod_memcg_lruvec_state re-entrant safe against irqs memcg: make count_memcg_events re-entrant safe against irqs memcg: make mod_memcg_state re-entrant safe against irqs memcg: move preempt disable to callers of memcg_rstat_updated memcg: memcg_rstat_updated re-entrant safe against irqs mm: khugepaged: decouple SHMEM and file folios' collapse selftests/eventfd: correct test name and improve messages alloc_tag: check mem_profiling_support in alloc_tag_init Docs/damon: update titles and brief introductions to explain DAMOS selftests/damon/_damon_sysfs: read tried regions directories in order mm/damon/tests/core-kunit: add a test for damos_set_filters_default_reject() mm/damon/paddr: remove unused variable, folio_list, in damon_pa_stat() mm/damon/sysfs-schemes: fix wrong comment on damons_sysfs_quota_goal_metric_strs ...
2025-05-11Documentation: zram: update IDLE pages tracking documentationSergey Senozhatsky
Move IDLE pages tracking into a separate chapter because there are multiple features that use (or depend on) it either in built-in variant ("mark all") or in extended variant (ac-time tracking). In addition, recompression doesn't require memory tracking to be enabled in order to be able to perform idle recompression. Link: https://lkml.kernel.org/r/20250416042833.3858827-1-senozhatsky@chromium.org Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> Reported-by: Shin Kawamura <kawasin@google.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Minchan Kim <minchan@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-11zram: modernize writeback interfaceSergey Senozhatsky
The writeback interface supports a page_index=N parameter which performs writeback of the given page. Since we rarely need to writeback just one single page, the typical use case involves a number of writeback calls, each performing writeback of one page: echo page_index=100 > zram0/writeback ... echo page_index=200 > zram0/writeback echo page_index=500 > zram0/writeback ... echo page_index=700 > zram0/writeback One obvious downside of this is that it increases the number of syscalls. Less obvious, but a significantly more important downside, is that when given only one page to post-process zram cannot perform an optimal target selection. This becomes a critical limitation when writeback_limit is enabled, because under writeback_limit we want to guarantee the highest memory savings hence we first need to writeback pages that release the highest amount of zsmalloc pool memory. This patch adds page_indexes=LOW-HIGH parameter to the writeback interface: echo page_indexes=100-200 page_indexes=500-700 > zram0/writeback This gives zram a chance to apply an optimal target selection strategy on each iteration of the writeback loop. We also now permit multiple page_index parameters per call (previously zram would recognize only one page_index) and a mix or single pages and page ranges: echo page_index=42 page_index=99 page_indexes=100-200 \ page_indexes=500-700 > zram0/writeback Apart from that the patch also unifies parameters passing and resembles other "modern" zram device attributes (e.g. recompression), while the old interface used a mixed scheme: values-less parameters for mode and a key=value format for page_index. We still support the "old" value-less format for compatibility reasons. [senozhatsky@chromium.org: simplify parse_page_index() range checks, per Brian] nk: https://lkml.kernel.org/r/20250404015327.2427684-1-senozhatsky@chromium.org [sozhatsky@chromium.org: fix uninitialized variable in zram_writeback_slots(), per Dan] nk: https://lkml.kernel.org/r/20250409112611.1154282-1-senozhatsky@chromium.org Link: https://lkml.kernel.org/r/20250327015818.4148660-1-senozhatsky@chromium.org Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> Reviewed-by: Brian Geffon <bgeffon@google.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Richard Chang <richardycc@google.com> Cc: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Dan Carpenter <dan.carpenter@linaro.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-01Documentation: Document the new zoned loop block device driverDamien Le Moal
Introduce the zoned_loop.rst documentation file under admin-guide/blockdev to document the zoned loop block device driver. An overview of the driver is provided and its usage to create and delete zoned devices described. Signed-off-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Link: https://lore.kernel.org/r/20250407075222.170336-3-dlemoal@kernel.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-03-16zram: remove max_comp_streams device attrSergey Senozhatsky
max_comp_streams device attribute has been defunct since May 2016 when zram switched to per-CPU compression streams, remove it. Link: https://lkml.kernel.org/r/20250303022425.285971-5-senozhatsky@chromium.org Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Hillf Danton <hdanton@sina.com> Cc: Kairui Song <ryncsn@gmail.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Yosry Ahmed <yosry.ahmed@linux.dev> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-12-13Documentation: zram: fix dictionary spellingSaru2003
Fixes a typo in the ZRAM documentation where 'dictioary' was misspelled. Corrected it to 'dictionary' in the example usage of 'algorithm_params'. Signed-off-by: Sarveshwaar SS <sarvesh20123@gmail.com> Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Link: https://lore.kernel.org/r/20241125165122.17521-1-sarvesh20123@gmail.com
2024-11-05zram: permit only one post-processing operation at a timeSergey Senozhatsky
Both recompress and writeback soon will unlock slots during processing, which makes things too complex wrt possible race-conditions. We still want to clear PP_SLOT in slot_free, because this is how we figure out that slot that was selected for post-processing has been released under us and when we start post-processing we check if slot still has PP_SLOT set. At the same time, theoretically, we can have something like this: CPU0 CPU1 recompress scan slots set PP_SLOT unlock slot slot_free clear PP_SLOT allocate PP_SLOT writeback scan slots set PP_SLOT unlock slot select PP-slot test PP_SLOT So recompress will not detect that slot has been re-used and re-selected for concurrent writeback post-processing. Make sure that we only permit on post-processing operation at a time. So now recompress and writeback post-processing don't race against each other, we only need to handle slot re-use (slot_free and write), which is handled individually by each pp operation. Having recompress and writeback competing for the same slots is not exactly good anyway (can't imagine anyone doing that). Link: https://lkml.kernel.org/r/20240917021020.883356-3-senozhatsky@chromium.org Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Minchan Kim <minchan@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-09-09zram: support priority parameter in recompressionSergey Senozhatsky
recompress device attribute supports alg=NAME parameter so that we can specify only one particular algorithm we want to perform recompression with. However, with algo params we now can have several exactly same secondary algorithms but each with its own params tuning (e.g. priority 1 configured to use more aggressive level, and priority 2 configured to use a pre-trained dictionary). Support priority=NUM parameter so that we can correctly determine which secondary algorithm we want to use. Link: https://lkml.kernel.org/r/20240902105656.1383858-25-senozhatsky@chromium.org Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Minchan Kim <minchan@kernel.org> Cc: Nick Terrell <terrelln@fb.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-09-09Documentation/zram: add documentation for algorithm parametersSergey Senozhatsky
Document brief description of compression algorithms' parameters: compression level and pre-trained dictionary. [senozhatsky@chromium.org: trivial fixup] Link: https://lkml.kernel.org/r/20240903063722.1603592-1-senozhatsky@chromium.org Link: https://lkml.kernel.org/r/20240902105656.1383858-24-senozhatsky@chromium.org Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Minchan Kim <minchan@kernel.org> Cc: Nick Terrell <terrelln@fb.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-09-09zram: introduce algorithm_params device attributeSergey Senozhatsky
This attribute is used to setup compression algorithms' parameters, so we can tweak algorithms' characteristics. At this point only 'level' is supported (to be extended in the future). Each call sets up parameters for one particular algorithm, which should be specified either by the algorithm's priority or algo name. This is expected to be called after corresponding algorithm is selected via comp_algorithm or recomp_algorithm. echo "priority=0 level=1" > /sys/block/zram0/algorithm_params or echo "algo=zstd level=1" > /sys/block/zram0/algorithm_params Link: https://lkml.kernel.org/r/20240902105656.1383858-16-senozhatsky@chromium.org Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Minchan Kim <minchan@kernel.org> Cc: Nick Terrell <terrelln@fb.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-09-09zram: introduce custom comp backends APISergey Senozhatsky
Moving to custom backends implementation gives us ability to have our own minimalistic and extendable API, and algorithms tunings becomes possible. The list of compression backends is empty at this point, we will add backends in the followup patches. Link: https://lkml.kernel.org/r/20240902105656.1383858-5-senozhatsky@chromium.org Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Minchan Kim <minchan@kernel.org> Cc: Nick Terrell <terrelln@fb.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-04-25zram: add max_pages param to recompressionSergey Senozhatsky
Introduce "max_pages" param to recompress device attribute which sets an upper limit on the number of entries (pages) zram attempts to recompress (in this particular recompression call). S/W recompression can be quite expensive so limiting the number of pages recompress touches can be quite helpful. Link: https://lkml.kernel.org/r/20240329094050.2815699-1-senozhatsky@chromium.org Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> Acked-by: Brian Geffon <bgeffon@google.com> Cc: Minchan Kim <minchan@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-12-10zram: split memory-tracking and ac-time trackingSergey Senozhatsky
ZRAM_MEMORY_TRACKING enables two features: - per-entry ac-time tracking - debugfs interface The latter one is the reason why memory-tracking depends on DEBUG_FS, while the former one is used far beyond debugging these days. Namely ac-time is used for fine grained writeback of idle entries (pages). Move ac-time tracking under its own config option so that it can be enabled (along with writeback) on systems without DEBUG_FS. [senozhatsky@chromium.org: ifdef fixup, per Dmytro] Link: https://lkml.kernel.org/r/20231117013543.540280-1-senozhatsky@chromium.org Link: https://lkml.kernel.org/r/20231115024223.4133148-1-senozhatsky@chromium.org Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Minchan Kim <minchan@kernel.org> Cc: Dmytro Maluka <dmaluka@chromium.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-04-27docs nbd: userspace NBD now favors github over sourceforgeEric Blake
While the sourceforge site for userspace NBD still exists, the code repository moved to github several years ago. Then with a recent patch[1], the github landing page contains just as much information as the sourceforge page, so we might as well point to a single location that also provides the code. [1] https://lists.debian.org/nbd/2023/03/msg00051.html Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Link: https://lore.kernel.org/r/20230410180611.1051618-5-eblake@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-01-31drivers/block: Remove PARIDE core and high-level protocolsOndrej Zary
Remove PARIDE core and high level protocols, taking care not to break low-level drivers (used by pata_parport). Also update documentation. Signed-off-by: Ondrej Zary <linux@zary.sk> Acked-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
2023-01-31ata: pata_parport: add driver (PARIDE replacement)Ondrej Zary
The pata_parport is a libata-based replacement of the old PARIDE subsystem - driver for parallel port IDE devices. It uses the original paride low-level protocol drivers but does not need the high-level drivers (pd, pcd, pf, pt, pg). The IDE devices behind parallel port adapters are handled by the ATA layer. This will allow paride and its high-level drivers to be removed. Unfortunately, libata drivers cannot sleep so pata_parport claims parport before activating the ata host and keeps it claimed (and protocol connected) until the ata host is removed. This means that no devices can be chained (neither other pata_parport devices nor a printer). paride and pata_parport are mutually exclusive because the compiled protocol drivers are incompatible. Tested with: - Imation SuperDisk LS-120 and HP C4381A (EPAT) - Freecom Parallel CD (FRPW) - Toshiba Mobile CD-RW 2793008 w/Freecom Parallel Cable rev.903 (FRIQ) - Backpack CD-RW 222011 and CD-RW 19350 (BPCK6) The following bugs in low-level protocol drivers were found and will be fixed later: Note: EPP-32 mode is buggy in EPAT - and also in all other protocol drivers - they don't handle non-multiple-of-4 block transfers correctly. This causes problems with LS-120 drive. There is also another bug in EPAT: EPP modes don't work unless a 4-bit or 8-bit mode is used first (probably some initialization missing?). Once the device is initialized, EPP works until power cycle. So after device power on, you have to: echo "parport0 epat 0" >/sys/bus/pata_parport/new_device echo pata_parport.0 >/sys/bus/pata_parport/delete_device echo "parport0 epat 4" >/sys/bus/pata_parport/new_device (autoprobe will initialize correctly as it tries the slowest modes first but you'll get the broken EPP-32 mode) Note: EPP modes are buggy in FRPW, only modes 0 and 1 work. Signed-off-by: Ondrej Zary <linux@zary.sk> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.de> Acked-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
2022-11-30zram: add incompressible flag to read_block_state()Sergey Senozhatsky
Add a new flag to zram block state that shows if the page is incompressible: that none of the algorithm (including secondary ones) could compress it. Link: https://lkml.kernel.org/r/20221109115047.2921851-14-senozhatsky@chromium.org Suggested-by: Minchan Kim <minchan@kernel.org> Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> Acked-by: Minchan Kim <minchan@kernel.org> Cc: Alexey Romanov <avromanov@sberdevices.ru> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Nitin Gupta <ngupta@vflare.org> Cc: Suleiman Souhlal <suleiman@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-11-30zram: add incompressible writebackSergey Senozhatsky
Add support for incompressible pages writeback: echo incompressible > /sys/block/zramX/writeback Link: https://lkml.kernel.org/r/20221109115047.2921851-13-senozhatsky@chromium.org Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> Acked-by: Minchan Kim <minchan@kernel.org> Cc: Alexey Romanov <avromanov@sberdevices.ru> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Nitin Gupta <ngupta@vflare.org> Cc: Suleiman Souhlal <suleiman@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-11-30documentation: add zram recompression documentationSergey Senozhatsky
Document user-space visible device attributes that are enabled by ZRAM_MULTI_COMP. Link: https://lkml.kernel.org/r/20221109115047.2921851-12-senozhatsky@chromium.org Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> Acked-by: Minchan Kim <minchan@kernel.org> Cc: Alexey Romanov <avromanov@sberdevices.ru> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Nitin Gupta <ngupta@vflare.org> Cc: Suleiman Souhlal <suleiman@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-11-30zram: add recompress flag to read_block_state()Sergey Senozhatsky
Add a new flag to zram block state that shows if the page was recompressed (using alternative compression algorithm). Link: https://lkml.kernel.org/r/20221109115047.2921851-6-senozhatsky@chromium.org Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> Acked-by: Minchan Kim <minchan@kernel.org> Cc: Alexey Romanov <avromanov@sberdevices.ru> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Nitin Gupta <ngupta@vflare.org> Cc: Suleiman Souhlal <suleiman@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-06-02Merge tag 'docs-5.19-2' of git://git.lwn.net/linuxLinus Torvalds
Pull documentation fixes from Jonathan Corbet: "A handful of late-arriving documentation fixes and the addition of an SVG tux logo which, I'm assured, we're going to want" * tag 'docs-5.19-2' of git://git.lwn.net/linux: documentation: Format button_dev as a pointer. docs: add SVG version of the Linux logo docs: move Linux logo into a new `images` folder docs: blockdev: change title to match section content docs/conf.py: Cope with removal of language=None in Sphinx 5.0.0
2022-06-01docs: blockdev: change title to match section contentJoel Colledge
This index.rst was added in commit 39443104c7d3 docs: blockdev: convert to ReST It appears that the title from the RapidIO index page was copied. This title does not match the content of this directory. Change it to match. Signed-off-by: Joel Colledge <joel.colledge@linbit.com> Link: https://lore.kernel.org/r/20220530142849.717-1-joel.colledge@linbit.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-04-29zram: add a huge_idle writeback modeBrian Geffon
Today it's only possible to write back as a page, idle, or huge. A user might want to writeback pages which are huge and idle first as these idle pages do not require decompression and make a good first pass for writeback. Idle writeback specifically has the advantage that a refault is unlikely given that the page has been swapped for some amount of time without being refaulted. Huge writeback has the advantage that you're guaranteed to get the maximum benefit from a single page writeback, that is, you're reclaiming one full page of memory. Pages which are compressed in zram being written back result in some benefit which is always less than a page size because of the fact that it was compressed. The primary use of this is for minimizing refaults in situations where the device has to be sensitive to storage endurance. On ChromeOS we have devices with slow eMMC and repeated writes and refaults can negatively affect performance and endurance. Link: https://lkml.kernel.org/r/20220322215821.1196994-1-bgeffon@google.com Signed-off-by: Brian Geffon <bgeffon@google.com> Acked-by: Minchan Kim <minchan@kernel.org> Cc: Nitin Gupta <ngupta@vflare.org> Cc: Sergey Senozhatsky <senozhatsky@chromium.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-02-15docs: Fix wording in optional zram feature docsEthan Dye
This fixes some simple grammar errors in the documentation for zram, specifically errors in the optional feature section of the zram documentation. Signed-off-by: Ethan Dye <mrtops03@gmail.com> Link: https://lore.kernel.org/r/20220207235442.95090-1-mrtops03@gmail.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-11-29docs: admin-guide/blockdev: Remove digraph of node-statesAkira Yokosawa
While node-states-8.dot has two digraphs, the dot(1) command can not properly handle multiple graphs in a DOT file and the kernel-doc page at https://www.kernel.org/doc/html/latest/admin-guide/blockdev/drbd/figures.html fails to render the graphs. It turned out that the digraph of node_states can be removed. Quote from Joel's reflection: On reflection, the digraph node_states can be removed entirely. It is too basic to contain any useful information. In addition it references "ioctl_set_state". The ioctl configuration interface for DRBD has long been removed. In fact, it was never in the upstream version of DRBD. Remove node_states and rename the DOT file peer_states-8.dot. Suggested-by: Joel Colledge <joel.colledge@linbit.com> Acked-by: Joel Colledge <joel.colledge@linbit.com> Signed-off-by: Akira Yokosawa <akiyks@gmail.com> Cc: Philipp Reisner <philipp.reisner@linbit.com> Cc: Lars Ellenberg <lars.ellenberg@linbit.com> Link: https://lore.kernel.org/r/7df04f45-8746-e666-1a9d-a998f1ab1f91@gmail.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-11-06zram: introduce an aged idle interfaceBrian Geffon
This change introduces an aged idle interface to the existing idle sysfs file for zram. When CONFIG_ZRAM_MEMORY_TRACKING is enabled the idle file now also accepts an integer argument. This integer is the age (in seconds) of pages to mark as idle. The idle file still supports 'all' as it always has. This new approach allows for much more control over which pages get marked as idle. [bgeffon@google.com: use IS_ENABLED and cleanup comment] Link: https://lkml.kernel.org/r/20210924161128.1508015-1-bgeffon@google.com [bgeffon@google.com: Sergey's cleanup suggestions] Link: https://lkml.kernel.org/r/20210929143056.13067-1-bgeffon@google.com Link: https://lkml.kernel.org/r/20210923130115.1344361-1-bgeffon@google.com Signed-off-by: Brian Geffon <bgeffon@google.com> Acked-by: Minchan Kim <minchan@kernel.org> Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Nitin Gupta <ngupta@vflare.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Suleiman Souhlal <suleiman@google.com> Cc: Jesse Barnes <jsbarnes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-12-15Merge branch 'akpm' (patches from Andrew)Linus Torvalds
Merge misc updates from Andrew Morton: - a few random little subsystems - almost all of the MM patches which are staged ahead of linux-next material. I'll trickle to post-linux-next work in as the dependents get merged up. Subsystems affected by this patch series: kthread, kbuild, ide, ntfs, ocfs2, arch, and mm (slab-generic, slab, slub, dax, debug, pagecache, gup, swap, shmem, memcg, pagemap, mremap, hmm, vmalloc, documentation, kasan, pagealloc, memory-failure, hugetlb, vmscan, z3fold, compaction, oom-kill, migration, cma, page-poison, userfaultfd, zswap, zsmalloc, uaccess, zram, and cleanups). * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (200 commits) mm: cleanup kstrto*() usage mm: fix fall-through warnings for Clang mm: slub: convert sysfs sprintf family to sysfs_emit/sysfs_emit_at mm: shmem: convert shmem_enabled_show to use sysfs_emit_at mm:backing-dev: use sysfs_emit in macro defining functions mm: huge_memory: convert remaining use of sprintf to sysfs_emit and neatening mm: use sysfs_emit for struct kobject * uses mm: fix kernel-doc markups zram: break the strict dependency from lzo zram: add stat to gather incompressible pages since zram set up zram: support page writeback mm/process_vm_access: remove redundant initialization of iov_r mm/zsmalloc.c: rework the list_add code in insert_zspage() mm/zswap: move to use crypto_acomp API for hardware acceleration mm/zswap: fix passing zero to 'PTR_ERR' warning mm/zswap: make struct kernel_param_ops definitions const userfaultfd/selftests: hint the test runner on required privilege userfaultfd/selftests: fix retval check for userfaultfd_open() userfaultfd/selftests: always dump something in modes userfaultfd: selftests: make __{s,u}64 format specifiers portable ...
2020-12-15zram: add stat to gather incompressible pages since zram set upMinchan Kim
Currently, zram supports the stat via /sys/block/zram/mm_stat to represent how many of incompressible pages are stored at the moment but it couldn't show how many times incompressible pages were wrote down since zram set up. It's also good indication to see how zram is effective in the system. Link: https://lkml.kernel.org/r/20201130201907.1284910-1-minchan@kernel.org Signed-off-by: Minchan Kim <minchan@kernel.org> Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-12-15zram: support page writebackMinchan Kim
There is demand to writeback specific process pages to backing store instead of all idles pages in the system due to storage wear out concerns and to launching latency of apps which are most of the time idle but are critical for resume latency. This patch extends the writeback knob to support a specific page writeback. Link: https://lkml.kernel.org/r/20201020190506.3758660-1-minchan@kernel.org Signed-off-by: Minchan Kim <minchan@kernel.org> Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-12-08Documentation: fix typos found in admin-guide subdirectoryAndrew Klychkov
Fixed twelve typos in cppc_sysfs.rst, binderfs.rst, paride.rst, zram.rst, bug-hunting.rst, introduction.rst, usage.rst, dm-crypt.rst Signed-off-by: Andrew Klychkov <andrew.a.klychkov@gmail.com> Reviewed-by: Jonathan Corbet <corbet@lwn.net> Reviewed-by: Randy Dunlap <rdunlap@infradead.org> Link: https://lore.kernel.org/r/20201204070235.GA48631@spblnx124.lan Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-09-24Documentation/admin-guide: blockdev/ramdisk: remove use of "rdev"Randy Dunlap
Remove use of "rdev" from blockdev/ramdisk.rst and update admin-guide/kernel-parameters.txt. "rdev" is considered antiquated, ancient, archaic, obsolete, deprecated {choose any or all}. "rdev" was removed from util-linux in 2010: https://git.kernel.org/pub/scm/utils/util-linux/util-linux.git/commit/?id=a3e40c14651fccf18e7954f081e601389baefe3f Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Cc: Karel Zak <kzak@redhat.com> Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: linux-block@vger.kernel.org Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Martin Mares <mj@ucw.cz> Cc: linux-video@atrey.karlin.mff.cuni.cz Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: linux-doc@vger.kernel.org Link: https://lore.kernel.org/r/20200918015640.8439-3-rdunlap@infradead.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-07-05Replace HTTP links with HTTPS ones: DRBD driverAlexander A. Klimov
Rationale: Reduces attack surface on kernel devs opening the links for MITM as HTTPS traffic is much harder to manipulate. Deterministic algorithm: For each file: If not .svg: For each line: If doesn't contain `\bxmlns\b`: For each link, `\bhttp://[^# \t\r\n]*(?:\w|/)`: If both the HTTP and HTTPS versions return 200 OK and serve the same content: Replace HTTP with HTTPS. Signed-off-by: Alexander A. Klimov <grandmaster@al2klimov.de> Link: https://lore.kernel.org/r/20200627103111.71771-1-grandmaster@al2klimov.de Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-02-13Documentation: zram: fix the description about orig_data_size of mm_statYue Hu
orig_data_size counted the same_pages by commit 51f9f82c855d ("zram: count same page write as page_stored"), so let's fix it. Signed-off-by: Yue Hu <zbestahu@163.com> Link: https://lore.kernel.org/r/20200206111031.9524-1-zbestahu@gmail.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-01-24zram: correct documentation about sysfs node of huge page writebackYue Hu
sysfs node for huge page writeback is writeback rather than write. Signed-off-by: Yue Hu <huyue2@yulong.com> Acked-by: Minchan Kim <minchan@kernel.org> Link: https://lore.kernel.org/r/20200120102949.12132-1-zbestahu@gmail.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-01-24Documentation: zram: various fixes in zram.rstRandy Dunlap
Fix various items in zram.rst: - typos/spellos - punctuation - grammar - shell syntax - indentation - sysfs file names Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Acked-by: Minchan Kim <minchan@kernel.org> Link: https://lore.kernel.org/r/77000e12-677a-62f6-9f78-343be5bd6630@infradead.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-07-15docs: add SPDX tags to new index filesMauro Carvalho Chehab
All those new files I added are under GPL v2.0 license. Add the corresponding SPDX headers to them. Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
2019-07-15docs: blockdev: add it to the admin-guideMauro Carvalho Chehab
The blockdev book basically contains user-faced documentation. Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>