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2022-05-09fs: Add aops->release_folioMatthew Wilcox (Oracle)
This replaces aops->releasepage. Update the documentation, and call it if it exists. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: Jeff Layton <jlayton@kernel.org>
2022-05-09doc: update documentation for swap_activate and swap_rwNeilBrown
This documentation for ->swap_activate() has been out-of-date for a long time. This patch updates it to match recent changes, and adds documentation for the associated ->swap_rw() Link: https://lkml.kernel.org/r/164859778126.29473.6778751233552859461.stgit@noble.brown Signed-off-by: NeilBrown <neilb@suse.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Tested-by: David Howells <dhowells@redhat.com> Tested-by: Geert Uytterhoeven <geert+renesas@glider.be> Cc: Hugh Dickins <hughd@google.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Trond Myklebust <trond.myklebust@hammerspace.com> Cc: Miaohe Lin <linmiaohe@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-05-09fs: Add read_folio documentationMatthew Wilcox (Oracle)
Convert all the ->readpage documentation to ->read_folio. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
2022-05-09docs: Add small intro to idmap examplesRodrigo Campos
When reading the documentation, I didn't understand why this list examples of things that fail without using the mount idmap feature. It seems pretty pointless and I doubted if I was missing something, until I finished the examples, the next section and saw the examples revisited. After that, it all made sense. Let's add one small sentence before, so the reader knows where this is going and why examples that don't might seem relevant are used. Link: https://lore.kernel.org/r/20220429135748.481301-1-rodrigo@sdfg.com.ar Reviewed-by: Christian Brauner (Microsoft) <brauner@kernel.org> Signed-off-by: Rodrigo Campos <rodrigo@sdfg.com.ar> Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
2022-05-08fs: Convert is_dirty_writeback() to take a folioMatthew Wilcox (Oracle)
Pass a folio instead of a page to aops->is_dirty_writeback(). Convert both implementations and the caller. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: Christoph Hellwig <hch@lst.de>
2022-05-08fs: Remove flags parameter from aops->write_beginMatthew Wilcox (Oracle)
There are no more aop flags left, so remove the parameter. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: Christoph Hellwig <hch@lst.de>
2022-05-08fs: Remove aop_flags parameter from netfs_write_begin()Matthew Wilcox (Oracle)
There are no more aop flags left, so remove the parameter. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: Christoph Hellwig <hch@lst.de>
2022-05-08namei: Merge page_symlink() and __page_symlink()Matthew Wilcox (Oracle)
There are no callers of __page_symlink() left, so we can remove that entry point. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Christian Brauner <brauner@kernel.org>
2022-04-26documentation: zonefs: Document sysfs attributesDamien Le Moal
Document the max_wro_seq_files, nr_wro_seq_files, max_active_seq_files and nr_active_seq_files sysfs attributes. Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Hans Holmberg <hans.holmberg@wdc.com> Reviewed-by: Sergey Shtylyov <s.shtylyov@omp.ru>
2022-04-25Merge tag 'f2fs-fix-5.18' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs Pull f2fs fixes from Jaegeuk Kim: "This includes major bug fixes introduced in 5.18-rc1 and 5.17+: - Remove obsolete whint_mode (5.18-rc1) - Fix IO split issue caused by op_flags change in f2fs (5.18-rc1) - Fix a wrong condition check to detect IO failure loop (5.18-rc1) - Fix wrong data truncation during roll-forward (5.17+)" * tag 'f2fs-fix-5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: f2fs: should not truncate blocks during roll-forward recovery f2fs: fix wrong condition check when failing metapage read f2fs: keep io_flags to avoid IO split due to different op_flags in two fio holders f2fs: remove obsolete whint_mode
2022-04-22Merge tag 'ext4_for_linus_stable' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4 Pull ext4 fixes from Ted Ts'o: "Fix some syzbot-detected bugs, as well as other bugs found by I/O injection testing. Change ext4's fallocate to consistently drop set[ug]id bits when an fallocate operation might possibly change the user-visible contents of a file. Also, improve handling of potentially invalid values in the the s_overhead_cluster superblock field to avoid ext4 returning a negative number of free blocks" * tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: jbd2: fix a potential race while discarding reserved buffers after an abort ext4: update the cached overhead value in the superblock ext4: force overhead calculation if the s_overhead_cluster makes no sense ext4: fix overhead calculation to account for the reserved gdt blocks ext4, doc: fix incorrect h_reserved size ext4: limit length to bitmap_maxbytes - blocksize in punch_hole ext4: fix use-after-free in ext4_search_dir ext4: fix bug_on in start_this_handle during umount filesystem ext4: fix symlink file size not match to file content ext4: fix fallocate to use file_modified to update permissions consistently
2022-04-21documentation: zonefs: Cleanup the mount options sectionDamien Le Moal
Use subsections to separate the descriptions of the "error=" and "explicit-open" mount sections. Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Hans Holmberg <hans.holmberg@wdc.com>
2022-04-20f2fs: remove obsolete whint_modeJaegeuk Kim
This patch removes obsolete whint_mode. Fixes: 41d36a9f3e53 ("fs: remove kiocb.ki_hint") Reviewed-by: Chao Yu <chao@kernel.org> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2022-04-12ext4, doc: fix incorrect h_reserved sizewangjianjian (C)
According to document and code, ext4_xattr_header's size is 32 bytes, so h_reserved size should be 3. Signed-off-by: Wang Jianjian <wangjianjian3@huawei.com> Link: https://lore.kernel.org/r/92fcc3a6-7d77-8c09-4126-377fcb4c46a5@huawei.com Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: stable@kernel.org
2022-04-08fscache: Remove the cookie parameter from fscache_clear_page_bits()Yue Hu
The cookie is not used at all, remove it and update the usage in io.c and afs/write.c (which is the only user outside of fscache currently) at the same time. [DH: Amended the documentation also] Signed-off-by: Yue Hu <huyue2@coolpad.com> Signed-off-by: David Howells <dhowells@redhat.com> cc: linux-cachefs@redhat.com Link: https://listman.redhat.com/archives/linux-cachefs/2022-April/006659.html
2022-04-08docs: filesystems: caching/backend-api.rst: fix an object withdrawn APIYue Hu
There's no fscache_are_objects_withdrawn() helper at all to test if cookie withdrawal is completed currently. The cache backend is using fscache_wait_for_objects() to wait all objects to be withdrawn. Signed-off-by: Yue Hu <huyue2@coolpad.com> Signed-off-by: David Howells <dhowells@redhat.com> cc: linux-cachefs@redhat.com Link: https://listman.redhat.com/archives/linux-cachefs/2022-April/006705.html # v1
2022-04-08docs: filesystems: caching/backend-api.rst: correct two relinquish APIs useYue Hu
1. cache backend is using fscache_relinquish_cache() rather than fscache_relinquish_cookie() to reset the cache cookie. 2. No fscache_cache_relinquish() helper currently, it should be fscache_relinquish_cache(). Signed-off-by: Yue Hu <huyue2@coolpad.com> Signed-off-by: David Howells <dhowells@redhat.com> cc: linux-cachefs@redhat.com Link: https://listman.redhat.com/archives/linux-cachefs/2022-April/006703.html # v1 Link: https://listman.redhat.com/archives/linux-cachefs/2022-April/006704.html # v2
2022-04-01Merge tag '5.18-rc-ksmbd-server-fixes' of git://git.samba.org/ksmbdLinus Torvalds
Pull ksmbd updates from Steve French: - three cleanup fixes - shorten module load warning - two documentation fixes * tag '5.18-rc-ksmbd-server-fixes' of git://git.samba.org/ksmbd: ksmbd: replace usage of found with dedicated list iterator variable ksmbd: Remove a redundant zeroing of memory MAINTAINERS: ksmbd: switch Sergey to reviewer ksmbd: shorten experimental warning on loading the module ksmbd: use netif_is_bridge_port Documentation: ksmbd: update Feature Status table
2022-04-01Merge tag 'folio-5.18d' of git://git.infradead.org/users/willy/pagecacheLinus Torvalds
Pull more filesystem folio updates from Matthew Wilcox: "A mixture of odd changes that didn't quite make it into the original pull and fixes for things that did. Also the readpages changes had to wait for the NFS tree to be pulled first. - Remove ->readpages infrastructure - Remove AOP_FLAG_CONT_EXPAND - Move read_descriptor_t to networking code - Pass the iocb to generic_perform_write - Minor updates to iomap, btrfs, ext4, f2fs, ntfs" * tag 'folio-5.18d' of git://git.infradead.org/users/willy/pagecache: btrfs: Remove a use of PAGE_SIZE in btrfs_invalidate_folio() ntfs: Correct mark_ntfs_record_dirty() folio conversion f2fs: Get the superblock from the mapping instead of the page f2fs: Correct f2fs_dirty_data_folio() conversion ext4: Correct ext4_journalled_dirty_folio() conversion filemap: Remove AOP_FLAG_CONT_EXPAND fs: Pass an iocb to generic_perform_write() fs, net: Move read_descriptor_t to net.h fs: Remove read_actor_t iomap: Simplify is_partially_uptodate a little readahead: Update comments mm: remove the skip_page argument to read_pages mm: remove the pages argument to read_pages fs: Remove ->readpages address space operation readahead: Remove read_cache_pages()
2022-04-01fs: Remove ->readpages address space operationMatthew Wilcox (Oracle)
All filesystems have now been converted to use ->readahead, so remove the ->readpages operation and fix all the comments that used to refer to it. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Al Viro <viro@zeniv.linux.org.uk> Acked-by: Al Viro <viro@zeniv.linux.org.uk>
2022-03-31Merge tag 'netfs-prep-20220318' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs Pull netfs updates from David Howells: "Netfs prep for write helpers. Having had a go at implementing write helpers and content encryption support in netfslib, it seems that the netfs_read_{,sub}request structs and the equivalent write request structs were almost the same and so should be merged, thereby requiring only one set of alloc/get/put functions and a common set of tracepoints. Merging the structs also has the advantage that if a bounce buffer is added to the request struct, a read operation can be performed to fill the bounce buffer, the contents of the buffer can be modified and then a write operation can be performed on it to send the data wherever it needs to go using the same request structure all the way through. The I/O handlers would then transparently perform any required crypto. This should make it easier to perform RMW cycles if needed. The potentially common functions and structs, however, by their names all proclaim themselves to be associated with the read side of things. The bulk of these changes alter this in the following ways: - Rename struct netfs_read_{,sub}request to netfs_io_{,sub}request. - Rename some enums, members and flags to make them more appropriate. - Adjust some comments to match. - Drop "read"/"rreq" from the names of common functions. For instance, netfs_get_read_request() becomes netfs_get_request(). - The ->init_rreq() and ->issue_op() methods become ->init_request() and ->issue_read(). I've kept the latter as a read-specific function and in another branch added an ->issue_write() method. The driver source is then reorganised into a number of files: fs/netfs/buffered_read.c Create read reqs to the pagecache fs/netfs/io.c Dispatchers for read and write reqs fs/netfs/main.c Some general miscellaneous bits fs/netfs/objects.c Alloc, get and put functions fs/netfs/stats.c Optional procfs statistics. and future development can be fitted into this scheme, e.g.: fs/netfs/buffered_write.c Modify the pagecache fs/netfs/buffered_flush.c Writeback from the pagecache fs/netfs/direct_read.c DIO read support fs/netfs/direct_write.c DIO write support fs/netfs/unbuffered_write.c Write modifications directly back Beyond the above changes, there are also some changes that affect how things work: - Make fscache_end_operation() generally available. - In the netfs tracing header, generate enums from the symbol -> string mapping tables rather than manually coding them. - Add a struct for filesystems that uses netfslib to put into their inode wrapper structs to hold extra state that netfslib is interested in, such as the fscache cookie. This allows netfslib functions to be set in filesystem operation tables and jumped to directly without having to have a filesystem wrapper. - Add a member to the struct added above to track the remote inode length as that may differ if local modifications are buffered. We may need to supply an appropriate EOF pointer when storing data (in AFS for example). - Pass extra information to netfs_alloc_request() so that the ->init_request() hook can access it and retain information to indicate the origin of the operation. - Make the ->init_request() hook return an error, thereby allowing a filesystem that isn't allowed to cache an inode (ceph or cifs, for example) to skip readahead. - Switch to using refcount_t for subrequests and add tracepoints to log refcount changes for the request and subrequest structs. - Add a function to consolidate dispatching a read request. Similar code is used in three places and another couple are likely to be added in the future" Link: https://lore.kernel.org/all/2639515.1648483225@warthog.procyon.org.uk/ * tag 'netfs-prep-20220318' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs: afs: Maintain netfs_i_context::remote_i_size netfs: Keep track of the actual remote file size netfs: Split some core bits out into their own file netfs: Split fs/netfs/read_helper.c netfs: Rename read_helper.c to io.c netfs: Prepare to split read_helper.c netfs: Add a function to consolidate beginning a read netfs: Add a netfs inode context ceph: Make ceph_init_request() check caps on readahead netfs: Change ->init_request() to return an error code netfs: Refactor arguments for netfs_alloc_read_request netfs: Adjust the netfs_failure tracepoint to indicate non-subreq lines netfs: Trace refcounting on the netfs_io_subrequest struct netfs: Trace refcounting on the netfs_io_request struct netfs: Adjust the netfs_rreq tracepoint slightly netfs: Split netfs_io_* object handling out netfs: Finish off rename of netfs_read_request to netfs_io_request netfs: Rename netfs_read_*request to netfs_io_*request netfs: Generate enums from trace symbol mapping lists fscache: export fscache_end_operation()
2022-03-22Merge tag 'folio-5.18b' of git://git.infradead.org/users/willy/pagecacheLinus Torvalds
Pull filesystem folio updates from Matthew Wilcox: "Primarily this series converts some of the address_space operations to take a folio instead of a page. Notably: - a_ops->is_partially_uptodate() takes a folio instead of a page and changes the type of the 'from' and 'count' arguments to make it obvious they're bytes. - a_ops->invalidatepage() becomes ->invalidate_folio() and has a similar type change. - a_ops->launder_page() becomes ->launder_folio() - a_ops->set_page_dirty() becomes ->dirty_folio() and adds the address_space as an argument. There are a couple of other misc changes up front that weren't worth separating into their own pull request" * tag 'folio-5.18b' of git://git.infradead.org/users/willy/pagecache: (53 commits) fs: Remove aops ->set_page_dirty fb_defio: Use noop_dirty_folio() fs: Convert __set_page_dirty_no_writeback to noop_dirty_folio fs: Convert __set_page_dirty_buffers to block_dirty_folio nilfs: Convert nilfs_set_page_dirty() to nilfs_dirty_folio() mm: Convert swap_set_page_dirty() to swap_dirty_folio() ubifs: Convert ubifs_set_page_dirty to ubifs_dirty_folio f2fs: Convert f2fs_set_node_page_dirty to f2fs_dirty_node_folio f2fs: Convert f2fs_set_data_page_dirty to f2fs_dirty_data_folio f2fs: Convert f2fs_set_meta_page_dirty to f2fs_dirty_meta_folio afs: Convert afs_dir_set_page_dirty() to afs_dir_dirty_folio() btrfs: Convert extent_range_redirty_for_io() to use folios fs: Convert trivial uses of __set_page_dirty_nobuffers to filemap_dirty_folio btrfs: Convert from set_page_dirty to dirty_folio fscache: Convert fscache_set_page_dirty() to fscache_dirty_folio() fs: Add aops->dirty_folio fs: Remove aops->launder_page orangefs: Convert launder_page to launder_folio nfs: Convert from launder_page to launder_folio fuse: Convert from launder_page to launder_folio ...
2022-03-22Merge branch 'akpm' (patches from Andrew)Linus Torvalds
Merge updates from Andrew Morton: - A few misc subsystems: kthread, scripts, ntfs, ocfs2, block, and vfs - Most the MM patches which precede the patches in Willy's tree: kasan, pagecache, gup, swap, shmem, memcg, selftests, pagemap, mremap, sparsemem, vmalloc, pagealloc, memory-failure, mlock, hugetlb, userfaultfd, vmscan, compaction, mempolicy, oom-kill, migration, thp, cma, autonuma, psi, ksm, page-poison, madvise, memory-hotplug, rmap, zswap, uaccess, ioremap, highmem, cleanups, kfence, hmm, and damon. * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (227 commits) mm/damon/sysfs: remove repeat container_of() in damon_sysfs_kdamond_release() Docs/ABI/testing: add DAMON sysfs interface ABI document Docs/admin-guide/mm/damon/usage: document DAMON sysfs interface selftests/damon: add a test for DAMON sysfs interface mm/damon/sysfs: support DAMOS stats mm/damon/sysfs: support DAMOS watermarks mm/damon/sysfs: support schemes prioritization mm/damon/sysfs: support DAMOS quotas mm/damon/sysfs: support DAMON-based Operation Schemes mm/damon/sysfs: support the physical address space monitoring mm/damon/sysfs: link DAMON for virtual address spaces monitoring mm/damon: implement a minimal stub for sysfs-based DAMON interface mm/damon/core: add number of each enum type values mm/damon/core: allow non-exclusive DAMON start/stop Docs/damon: update outdated term 'regions update interval' Docs/vm/damon/design: update DAMON-Idle Page Tracking interference handling Docs/vm/damon: call low level monitoring primitives the operations mm/damon: remove unnecessary CONFIG_DAMON option mm/damon/paddr,vaddr: remove damon_{p,v}a_{target_valid,set_operations}() mm/damon/dbgfs-test: fix is_target_id() change ...
2022-03-22fs: introduce alloc_inode_sb() to allocate filesystems specific inodeMuchun Song
The allocated inode cache is supposed to be added to its memcg list_lru which should be allocated as well in advance. That can be done by kmem_cache_alloc_lru() which allocates object and list_lru. The file systems is main user of it. So introduce alloc_inode_sb() to allocate file system specific inodes and set up the inode reclaim context properly. The file system is supposed to use alloc_inode_sb() to allocate inodes. In later patches, we will convert all users to the new API. Link: https://lkml.kernel.org/r/20220228122126.37293-4-songmuchun@bytedance.com Signed-off-by: Muchun Song <songmuchun@bytedance.com> Reviewed-by: Roman Gushchin <roman.gushchin@linux.dev> Cc: Alex Shi <alexs@kernel.org> Cc: Anna Schumaker <Anna.Schumaker@Netapp.com> Cc: Chao Yu <chao@kernel.org> Cc: Dave Chinner <david@fromorbit.com> Cc: Fam Zheng <fam.zheng@bytedance.com> Cc: Jaegeuk Kim <jaegeuk@kernel.org> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Kari Argillander <kari.argillander@gmail.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Qi Zheng <zhengqi.arch@bytedance.com> Cc: Shakeel Butt <shakeelb@google.com> Cc: Theodore Ts'o <tytso@mit.edu> Cc: Trond Myklebust <trond.myklebust@hammerspace.com> Cc: Vladimir Davydov <vdavydov.dev@gmail.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Wei Yang <richard.weiyang@gmail.com> Cc: Xiongchun Duan <duanxiongchun@bytedance.com> Cc: Yang Shi <shy828301@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-22mm: document and polish read-ahead codeNeilBrown
Add some "big-picture" documentation for read-ahead and polish the code to make it fit this documentation. The meaning of ->async_size is clarified to match its name. i.e. Any request to ->readahead() has a sync part and an async part. The caller will wait for the sync pages to complete, but will not wait for the async pages. The first async page is still marked PG_readahead Note that the current function names page_cache_sync_ra() and page_cache_async_ra() are misleading. All ra request are partly sync and partly async, so either part can be empty. A page_cache_sync_ra() request will usually set ->async_size non-zero, implying it is not all synchronous. When a non-zero req_count is passed to page_cache_async_ra(), the implication is that some prefix of the request is synchronous, though the calculation made there is incorrect - I haven't tried to fix it. Link: https://lkml.kernel.org/r/164549983734.9187.11586890887006601405.stgit@noble.brown Signed-off-by: NeilBrown <neilb@suse.de> Cc: Anna Schumaker <Anna.Schumaker@Netapp.com> Cc: Chao Yu <chao@kernel.org> Cc: Darrick J. Wong <djwong@kernel.org> Cc: Ilya Dryomov <idryomov@gmail.com> Cc: Jaegeuk Kim <jaegeuk@kernel.org> Cc: Jan Kara <jack@suse.cz> Cc: Jeff Layton <jlayton@kernel.org> Cc: Jens Axboe <axboe@kernel.dk> Cc: Lars Ellenberg <lars.ellenberg@linbit.com> Cc: Miklos Szeredi <miklos@szeredi.hu> Cc: Paolo Valente <paolo.valente@linaro.org> Cc: Philipp Reisner <philipp.reisner@linbit.com> Cc: Ryusuke Konishi <konishi.ryusuke@gmail.com> Cc: Trond Myklebust <trond.myklebust@hammerspace.com> Cc: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-22Merge tag 'ext4_for_linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4 Pull ext4 updates from Ted Ts'o: "Fix some bugs in converting ext4 to use the new mount API, as well as more bug fixes and clean ups in the ext4 fast_commit feature (most notably, in the tracepoints). In the jbd2 layer, the t_handle_lock spinlock has been removed, with the last place where it was actually needed replaced with an atomic cmpxchg" * tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (35 commits) ext4: fix kernel doc warnings ext4: fix remaining two trace events to use same printk convention ext4: add commit tid info in ext4_fc_commit_start/stop trace events ext4: add commit_tid info in jbd debug log ext4: add transaction tid info in fc_track events ext4: add new trace event in ext4_fc_cleanup ext4: return early for non-eligible fast_commit track events ext4: do not call FC trace event in ext4_fc_commit() if FS does not support FC ext4: convert ext4_fc_track_dentry type events to use event class ext4: fix ext4_fc_stats trace point ext4: remove unused enum EXT4_FC_COMMIT_FAILED ext4: warn when dirtying page w/o buffers in data=journal mode doc: fixed a typo in ext4 documentation ext4: make mb_optimize_scan performance mount option work with extents ext4: make mb_optimize_scan option work with set/unset mount cmd ext4: don't BUG if someone dirty pages without asking ext4 first ext4: remove redundant assignment to variable split_flag1 ext4: fix underflow in ext4_max_bitmap_size() ext4: fix ext4_mb_clear_bb() kernel-doc comment ext4: fix fs corruption when tring to remove a non-empty directory with IO error ...
2022-03-22Merge tag 'nfsd-5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linuxLinus Torvalds
Pull nfsd updates from Chuck Lever: "New features: - NFSv3 support in NFSD is now always built - Added NFSD support for the NFSv4 birth-time file attribute - Added support for storing and displaying sockaddrs in trace points - NFSD now recognizes RPC_AUTH_TLS probes Performance improvements: - Optimized the svc transport enqueuing mechanism - Added micro-optimizations for the duplicate reply cache Notable bug fixes: - Allocation of the NFSD file cache hash table is more reliable" * tag 'nfsd-5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux: (30 commits) nfsd: fix using the correct variable for sizeof() nfsd: use correct format characters NFSD: prevent integer overflow on 32 bit systems NFSD: prevent underflow in nfssvc_decode_writeargs() fs/lock: documentation cleanup. Replace inode->i_lock with flc_lock. NFSD: Fix nfsd_breaker_owns_lease() return values NFSD: Clean up _lm_ operation names arch: Remove references to CONFIG_NFSD_V3 in the default configs NFSD: Remove CONFIG_NFSD_V3 nfsd: more robust allocation failure handling in nfsd_file_cache_init SUNRPC: Teach server to recognize RPC_AUTH_TLS NFSD: Move svc_serv_ops::svo_function into struct svc_serv NFSD: Remove svc_serv_ops::svo_module SUNRPC: Remove svc_shutdown_net() SUNRPC: Rename svc_close_xprt() SUNRPC: Rename svc_create_xprt() SUNRPC: Remove svo_shutdown method SUNRPC: Merge svc_do_enqueue_xprt() into svc_enqueue_xprt() SUNRPC: Remove the .svo_enqueue_xprt method SUNRPC: Record endpoint information in trace log ...
2022-03-22Merge tag 'erofs-for-5.18-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs Pull erofs updates from Gao Xiang: "In this cycle, we continue converting to use meta buffers for all remaining uncompressed paths to prepare for the upcoming subpage, folio and fscache features. We also fixed a double-free issue when sysfs initialization fails, which was reported by syzbot. Besides, in order for the userspace to control per-file timestamp easier, we now switch to record mtime instead of ctime with a compatible feature marked. And there are also some code cleanups and documentation update as usual. Summary: - Avoid using page structure directly for all uncompressed paths - Fix a double-free issue when sysfs initialization fails - Complete DAX description for erofs - Use mtime instead since there's no (easy) way for users to control ctime - Several code cleanups" * tag 'erofs-for-5.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs: erofs: rename ctime to mtime erofs: use meta buffers for inode lookup erofs: use meta buffers for reading directories fs: erofs: add sanity check for kobject in erofs_unregister_sysfs erofs: refine managed inode stuffs erofs: clean up z_erofs_extent_lookback erofs: silence warnings related to impossible m_plen Documentation/filesystem/dax: update DAX description on erofs erofs: clean up preload_compressed_pages() erofs: get rid of `struct z_erofs_collector' erofs: use meta buffers for erofs_read_superblock()
2022-03-20Documentation: ksmbd: update Feature Status tableNamjae Jeon
As RDMA connection with Windows client becomes possible, change SMB direct to Supported from Partially Supported in the Feature Status table. It also adds new RSS mode support. Signed-off-by: Namjae Jeon <linkinjeon@kernel.org> Signed-off-by: Steve French <stfrench@microsoft.com>
2022-03-18netfs: Rename read_helper.c to io.cDavid Howells
Rename the read_helper.c file to io.c before splitting out the buffered read functions and some other bits. Changes ======= ver #2) - Rename read_helper.c before splitting. Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> cc: linux-cachefs@redhat.com Link: https://lore.kernel.org/r/164678216109.1200972.16567696909952495832.stgit@warthog.procyon.org.uk/ # v2 Link: https://lore.kernel.org/r/164692918076.2099075.8120961172717347610.stgit@warthog.procyon.org.uk/ # v3
2022-03-18netfs: Add a netfs inode contextDavid Howells
Add a netfs_i_context struct that should be included in the network filesystem's own inode struct wrapper, directly after the VFS's inode struct, e.g.: struct my_inode { struct { /* These must be contiguous */ struct inode vfs_inode; struct netfs_i_context netfs_ctx; }; }; The netfs_i_context struct so far contains a single field for the network filesystem to use - the cache cookie: struct netfs_i_context { ... struct fscache_cookie *cache; }; Three functions are provided to help with this: (1) void netfs_i_context_init(struct inode *inode, const struct netfs_request_ops *ops); Initialise the netfs context and set the operations. (2) struct netfs_i_context *netfs_i_context(struct inode *inode); Find the netfs context from the VFS inode. (3) struct inode *netfs_inode(struct netfs_i_context *ctx); Find the VFS inode from the netfs context. Changes ======= ver #4) - Fix netfs_is_cache_enabled() to check cookie->cache_priv to see if a cache is present[3]. - Fix netfs_skip_folio_read() to zero out all of the page, not just some of it[3]. ver #3) - Split out the bit to move ceph cap-getting on readahead into ceph_init_request()[1]. - Stick in a comment to the netfs inode structs indicating the contiguity requirements[2]. ver #2) - Adjust documentation to match. - Use "#if IS_ENABLED()" in netfs_i_cookie(), not "#ifdef". - Move the cap check from ceph_readahead() to ceph_init_request() to be called from netfslib. - Remove ceph_readahead() and use netfs_readahead() directly instead. Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Jeff Layton <jlayton@kernel.org> cc: linux-cachefs@redhat.com Link: https://lore.kernel.org/r/8af0d47f17d89c06bbf602496dd845f2b0bf25b3.camel@kernel.org/ [1] Link: https://lore.kernel.org/r/beaf4f6a6c2575ed489adb14b257253c868f9a5c.camel@kernel.org/ [2] Link: https://lore.kernel.org/r/3536452.1647421585@warthog.procyon.org.uk/ [3] Link: https://lore.kernel.org/r/164622984545.3564931.15691742939278418580.stgit@warthog.procyon.org.uk/ # v1 Link: https://lore.kernel.org/r/164678213320.1200972.16807551936267647470.stgit@warthog.procyon.org.uk/ # v2 Link: https://lore.kernel.org/r/164692909854.2099075.9535537286264248057.stgit@warthog.procyon.org.uk/ # v3 Link: https://lore.kernel.org/r/306388.1647595110@warthog.procyon.org.uk/ # v4
2022-03-18netfs: Finish off rename of netfs_read_request to netfs_io_requestDavid Howells
Adjust helper function names and comments after mass rename of struct netfs_read_*request to struct netfs_io_*request. Changes ======= ver #2) - Make the changes in the docs also. Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> cc: linux-cachefs@redhat.com Link: https://lore.kernel.org/r/164622992433.3564931.6684311087845150271.stgit@warthog.procyon.org.uk/ # v1 Link: https://lore.kernel.org/r/164678196111.1200972.5001114956865989528.stgit@warthog.procyon.org.uk/ # v2 Link: https://lore.kernel.org/r/164692892567.2099075.13895804222087028813.stgit@warthog.procyon.org.uk/ # v3
2022-03-18netfs: Rename netfs_read_*request to netfs_io_*requestDavid Howells
Rename netfs_read_*request to netfs_io_*request so that the same structures can be used for the write helpers too. perl -p -i -e 's/netfs_read_(request|subrequest)/netfs_io_$1/g' \ `git grep -l 'netfs_read_\(sub\|\)request'` perl -p -i -e 's/nr_rd_ops/nr_outstanding/g' \ `git grep -l nr_rd_ops` perl -p -i -e 's/nr_wr_ops/nr_copy_ops/g' \ `git grep -l nr_wr_ops` perl -p -i -e 's/netfs_read_source/netfs_io_source/g' \ `git grep -l 'netfs_read_source'` perl -p -i -e 's/netfs_io_request_ops/netfs_request_ops/g' \ `git grep -l 'netfs_io_request_ops'` perl -p -i -e 's/init_rreq/init_request/g' \ `git grep -l 'init_rreq'` Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> cc: linux-cachefs@redhat.com Link: https://lore.kernel.org/r/164622988070.3564931.7089670190434315183.stgit@warthog.procyon.org.uk/ # v1 Link: https://lore.kernel.org/r/164678195157.1200972.366609966927368090.stgit@warthog.procyon.org.uk/ # v2 Link: https://lore.kernel.org/r/164692891535.2099075.18435198075367420588.stgit@warthog.procyon.org.uk/ # v3
2022-03-17erofs: rename ctime to mtimeDavid Anderson
EROFS images should inherit modification time rather than change time, since users and host tooling have no easy way to control change time. To reflect the new timestamp meaning, i_ctime and i_ctime_nsec are renamed to i_mtime and i_mtime_nsec. Link: https://lore.kernel.org/r/20220311041829.3109511-1-dvander@google.com # v1 Signed-off-by: David Anderson <dvander@google.com> [ Gao Xiang: update document as well. ] Reviewed-by: Chao Yu <chao@kernel.org> Link: https://lore.kernel.org/r/20220317114959.106787-1-hsiangkao@linux.alibaba.com # v2 Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2022-03-16Documentation/filesystem/dax: update DAX description on erofslihongnan
Add missing erofs fsdax description since fsdax has been supported on erofs from Linux 5.15. Link: https://lore.kernel.org/r/20220308034139.93748-1-hongnan.li@linux.alibaba.com Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com> Acked-by: Chao Yu <chao@kernel.org> Signed-off-by: lihongnan <hongnan.lhn@alibaba-inc.com> Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
2022-03-15fscache: Convert fscache_set_page_dirty() to fscache_dirty_folio()Matthew Wilcox (Oracle)
Convert all users of fscache_set_page_dirty to use fscache_dirty_folio. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Tested-by: Damien Le Moal <damien.lemoal@opensource.wdc.com> Acked-by: Damien Le Moal <damien.lemoal@opensource.wdc.com> Tested-by: Mike Marshall <hubcap@omnibond.com> # orangefs Tested-by: David Howells <dhowells@redhat.com> # afs
2022-03-15fs: Add aops->dirty_folioMatthew Wilcox (Oracle)
This replaces ->set_page_dirty(). It returns a bool instead of an int and takes the address_space as a parameter instead of expecting the implementations to retrieve the address_space from the page. This is particularly important for filesystems which use FS_OPS for swap. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Tested-by: Damien Le Moal <damien.lemoal@opensource.wdc.com> Acked-by: Damien Le Moal <damien.lemoal@opensource.wdc.com> Tested-by: Mike Marshall <hubcap@omnibond.com> # orangefs Tested-by: David Howells <dhowells@redhat.com> # afs
2022-03-15fs: Add aops->launder_folioMatthew Wilcox (Oracle)
Since the only difference between ->launder_page and ->launder_folio is the type of the pointer, these can safely use a union without affecting bisectability. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Tested-by: Damien Le Moal <damien.lemoal@opensource.wdc.com> Acked-by: Damien Le Moal <damien.lemoal@opensource.wdc.com> Tested-by: Mike Marshall <hubcap@omnibond.com> # orangefs Tested-by: David Howells <dhowells@redhat.com> # afs
2022-03-15fs: Remove aops->invalidatepageMatthew Wilcox (Oracle)
With all users migrated to ->invalidate_folio, remove the old operation. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Tested-by: Damien Le Moal <damien.lemoal@opensource.wdc.com> Acked-by: Damien Le Moal <damien.lemoal@opensource.wdc.com> Tested-by: Mike Marshall <hubcap@omnibond.com> # orangefs Tested-by: David Howells <dhowells@redhat.com> # afs
2022-03-15fs: Add invalidate_folio() aops methodMatthew Wilcox (Oracle)
This is used in preference to invalidatepage, if defined. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Tested-by: Damien Le Moal <damien.lemoal@opensource.wdc.com> Acked-by: Damien Le Moal <damien.lemoal@opensource.wdc.com> Tested-by: Mike Marshall <hubcap@omnibond.com> # orangefs Tested-by: David Howells <dhowells@redhat.com> # afs
2022-03-14fs: Convert is_partially_uptodate to foliosMatthew Wilcox (Oracle)
Since the uptodate property is maintained on a per-folio basis, the is_partially_uptodate method should also take a folio. Fix the types at the same time so it's clear that it returns true/false and takes the count in bytes, not blocks. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Tested-by: Damien Le Moal <damien.lemoal@opensource.wdc.com> Acked-by: Damien Le Moal <damien.lemoal@opensource.wdc.com> Tested-by: Mike Marshall <hubcap@omnibond.com> # orangefs Tested-by: David Howells <dhowells@redhat.com> # afs
2022-03-12doc: fixed a typo in ext4 documentationlianzhi chang
The unit of file system size should be TiB, not PiB Signed-off-by: lianzhi chang <changlianzhi@uniontech.com> Link: https://lore.kernel.org/r/20220310014415.29937-1-changlianzhi@uniontech.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2022-03-11fs/lock: documentation cleanup. Replace inode->i_lock with flc_lock.Dai Ngo
Update lock usage of lock_manager_operations' functions to reflect the changes in commit 6109c85037e5 ("locks: add a dedicated spinlock to protect i_flctx lists"). Signed-off-by: Dai Ngo <dai.ngo@oracle.com> Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Reviewed-by: Jeff Layton <jlayton@kernel.org>
2022-02-08fscrypt: update documentation for direct I/O supportEric Biggers
Now that direct I/O is supported on encrypted files in some cases, document what these cases are. Link: https://lore.kernel.org/r/20220128233940.79464-6-ebiggers@kernel.org Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Eric Biggers <ebiggers@google.com>
2022-02-01netfs, cachefiles: Add a method to query presence of data in the cacheDavid Howells
Add a netfs_cache_ops method by which a network filesystem can ask the cache about what data it has available and where so that it can make a multipage read more efficient. Signed-off-by: David Howells <dhowells@redhat.com> cc: linux-cachefs@redhat.com Acked-by: Jeff Layton <jlayton@kernel.org> Reviewed-by: Rohith Surabattula <rohiths@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2022-01-20Merge tag 'ceph-for-5.17-rc1' of git://github.com/ceph/ceph-clientLinus Torvalds
Pull ceph updates from Ilya Dryomov: "The highlight is the new mount "device" string syntax implemented by Venky Shankar. It solves some long-standing issues with using different auth entities and/or mounting different CephFS filesystems from the same cluster, remounting and also misleading /proc/mounts contents. The existing syntax of course remains to be maintained. On top of that, there is a couple of fixes for edge cases in quota and a new mount option for turning on unbuffered I/O mode globally instead of on a per-file basis with ioctl(CEPH_IOC_SYNCIO)" * tag 'ceph-for-5.17-rc1' of git://github.com/ceph/ceph-client: ceph: move CEPH_SUPER_MAGIC definition to magic.h ceph: remove redundant Lsx caps check ceph: add new "nopagecache" option ceph: don't check for quotas on MDS stray dirs ceph: drop send metrics debug message rbd: make const pointer spaces a static const array ceph: Fix incorrect statfs report for small quota ceph: mount syntax module parameter doc: document new CephFS mount device syntax ceph: record updated mon_addr on remount ceph: new device mount syntax libceph: rename parse_fsid() to ceph_parse_fsid() and export libceph: generalize addr/ip parsing based on delimiter
2022-01-19Merge tag 'f2fs-for-5.17-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs Pull f2fs updates from Jaegeuk Kim: "In this round, we've tried to address some performance issues in f2fs_checkpoint and direct IO flows. Also, there was a work to enhance the page cache management used for compression. Other than them, we've done typical work including sysfs, code clean-ups, tracepoint, sanity check, in addition to bug fixes on corner cases. Enhancements: - use iomap for direct IO - try to avoid lock contention to improve f2fs_ckpt speed - avoid unnecessary memory allocation in compression flow - POSIX_FADV_DONTNEED drops the page cache containing compression pages - add some sysfs entries (gc_urgent_high_remaining, pending_discard) Bug fixes: - try not to expose unwritten blocks to user by DIO (this was added to avoid merge conflict; another patch is coming to address other missing case) - relax minor error condition for file pinning feature used in Android OTA - fix potential deadlock case in compression flow - should not truncate any block on pinned file In addition, we've done some code clean-ups and tracepoint/sanity check improvement" * tag 'f2fs-for-5.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (29 commits) f2fs: do not allow partial truncation on pinned file f2fs: remove redunant invalidate compress pages f2fs: Simplify bool conversion f2fs: don't drop compressed page cache in .{invalidate,release}page f2fs: fix to reserve space for IO align feature f2fs: fix to check available space of CP area correctly in update_ckpt_flags() f2fs: support fault injection to f2fs_trylock_op() f2fs: clean up __find_inline_xattr() with __find_xattr() f2fs: fix to do sanity check on last xattr entry in __f2fs_setxattr() f2fs: do not bother checkpoint by f2fs_get_node_info f2fs: avoid down_write on nat_tree_lock during checkpoint f2fs: compress: fix potential deadlock of compress file f2fs: avoid EINVAL by SBI_NEED_FSCK when pinning a file f2fs: add gc_urgent_high_remaining sysfs node f2fs: fix to do sanity check in is_alive() f2fs: fix to avoid panic in is_alive() if metadata is inconsistent f2fs: fix to do sanity check on inode type during garbage collection f2fs: avoid duplicate call of mark_inode_dirty f2fs: show number of pending discard commands f2fs: support POSIX_FADV_DONTNEED drop compressed page cache ...
2022-01-15Merge branch 'akpm' (patches from Andrew)Linus Torvalds
Merge misc updates from Andrew Morton: "146 patches. Subsystems affected by this patch series: kthread, ia64, scripts, ntfs, squashfs, ocfs2, vfs, and mm (slab-generic, slab, kmemleak, dax, kasan, debug, pagecache, gup, shmem, frontswap, memremap, memcg, selftests, pagemap, dma, vmalloc, memory-failure, hugetlb, userfaultfd, vmscan, mempolicy, oom-kill, hugetlbfs, migration, thp, ksm, page-poison, percpu, rmap, zswap, zram, cleanups, hmm, and damon)" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (146 commits) mm/damon: hide kernel pointer from tracepoint event mm/damon/vaddr: hide kernel pointer from damon_va_three_regions() failure log mm/damon/vaddr: use pr_debug() for damon_va_three_regions() failure logging mm/damon/dbgfs: remove an unnecessary variable mm/damon: move the implementation of damon_insert_region to damon.h mm/damon: add access checking for hugetlb pages Docs/admin-guide/mm/damon/usage: update for schemes statistics mm/damon/dbgfs: support all DAMOS stats Docs/admin-guide/mm/damon/reclaim: document statistics parameters mm/damon/reclaim: provide reclamation statistics mm/damon/schemes: account how many times quota limit has exceeded mm/damon/schemes: account scheme actions that successfully applied mm/damon: remove a mistakenly added comment for a future feature Docs/admin-guide/mm/damon/usage: update for kdamond_pid and (mk|rm)_contexts Docs/admin-guide/mm/damon/usage: mention tracepoint at the beginning Docs/admin-guide/mm/damon/usage: remove redundant information Docs/admin-guide/mm/damon/usage: update for scheme quotas and watermarks mm/damon: convert macro functions to static inline functions mm/damon: modify damon_rand() macro to static inline function mm/damon: move damon_rand() definition into damon.h ...
2022-01-15mm: add a field to store names for private anonymous memoryColin Cross
In many userspace applications, and especially in VM based applications like Android uses heavily, there are multiple different allocators in use. At a minimum there is libc malloc and the stack, and in many cases there are libc malloc, the stack, direct syscalls to mmap anonymous memory, and multiple VM heaps (one for small objects, one for big objects, etc.). Each of these layers usually has its own tools to inspect its usage; malloc by compiling a debug version, the VM through heap inspection tools, and for direct syscalls there is usually no way to track them. On Android we heavily use a set of tools that use an extended version of the logic covered in Documentation/vm/pagemap.txt to walk all pages mapped in userspace and slice their usage by process, shared (COW) vs. unique mappings, backing, etc. This can account for real physical memory usage even in cases like fork without exec (which Android uses heavily to share as many private COW pages as possible between processes), Kernel SamePage Merging, and clean zero pages. It produces a measurement of the pages that only exist in that process (USS, for unique), and a measurement of the physical memory usage of that process with the cost of shared pages being evenly split between processes that share them (PSS). If all anonymous memory is indistinguishable then figuring out the real physical memory usage (PSS) of each heap requires either a pagemap walking tool that can understand the heap debugging of every layer, or for every layer's heap debugging tools to implement the pagemap walking logic, in which case it is hard to get a consistent view of memory across the whole system. Tracking the information in userspace leads to all sorts of problems. It either needs to be stored inside the process, which means every process has to have an API to export its current heap information upon request, or it has to be stored externally in a filesystem that somebody needs to clean up on crashes. It needs to be readable while the process is still running, so it has to have some sort of synchronization with every layer of userspace. Efficiently tracking the ranges requires reimplementing something like the kernel vma trees, and linking to it from every layer of userspace. It requires more memory, more syscalls, more runtime cost, and more complexity to separately track regions that the kernel is already tracking. This patch adds a field to /proc/pid/maps and /proc/pid/smaps to show a userspace-provided name for anonymous vmas. The names of named anonymous vmas are shown in /proc/pid/maps and /proc/pid/smaps as [anon:<name>]. Userspace can set the name for a region of memory by calling prctl(PR_SET_VMA, PR_SET_VMA_ANON_NAME, start, len, (unsigned long)name) Setting the name to NULL clears it. The name length limit is 80 bytes including NUL-terminator and is checked to contain only printable ascii characters (including space), except '[',']','\','$' and '`'. Ascii strings are being used to have a descriptive identifiers for vmas, which can be understood by the users reading /proc/pid/maps or /proc/pid/smaps. Names can be standardized for a given system and they can include some variable parts such as the name of the allocator or a library, tid of the thread using it, etc. The name is stored in a pointer in the shared union in vm_area_struct that points to a null terminated string. Anonymous vmas with the same name (equivalent strings) and are otherwise mergeable will be merged. The name pointers are not shared between vmas even if they contain the same name. The name pointer is stored in a union with fields that are only used on file-backed mappings, so it does not increase memory usage. CONFIG_ANON_VMA_NAME kernel configuration is introduced to enable this feature. It keeps the feature disabled by default to prevent any additional memory overhead and to avoid confusing procfs parsers on systems which are not ready to support named anonymous vmas. The patch is based on the original patch developed by Colin Cross, more specifically on its latest version [1] posted upstream by Sumit Semwal. It used a userspace pointer to store vma names. In that design, name pointers could be shared between vmas. However during the last upstreaming attempt, Kees Cook raised concerns [2] about this approach and suggested to copy the name into kernel memory space, perform validity checks [3] and store as a string referenced from vm_area_struct. One big concern is about fork() performance which would need to strdup anonymous vma names. Dave Hansen suggested experimenting with worst-case scenario of forking a process with 64k vmas having longest possible names [4]. I ran this experiment on an ARM64 Android device and recorded a worst-case regression of almost 40% when forking such a process. This regression is addressed in the followup patch which replaces the pointer to a name with a refcounted structure that allows sharing the name pointer between vmas of the same name. Instead of duplicating the string during fork() or when splitting a vma it increments the refcount. [1] https://lore.kernel.org/linux-mm/20200901161459.11772-4-sumit.semwal@linaro.org/ [2] https://lore.kernel.org/linux-mm/202009031031.D32EF57ED@keescook/ [3] https://lore.kernel.org/linux-mm/202009031022.3834F692@keescook/ [4] https://lore.kernel.org/linux-mm/5d0358ab-8c47-2f5f-8e43-23b89d6a8e95@intel.com/ Changes for prctl(2) manual page (in the options section): PR_SET_VMA Sets an attribute specified in arg2 for virtual memory areas starting from the address specified in arg3 and spanning the size specified in arg4. arg5 specifies the value of the attribute to be set. Note that assigning an attribute to a virtual memory area might prevent it from being merged with adjacent virtual memory areas due to the difference in that attribute's value. Currently, arg2 must be one of: PR_SET_VMA_ANON_NAME Set a name for anonymous virtual memory areas. arg5 should be a pointer to a null-terminated string containing the name. The name length including null byte cannot exceed 80 bytes. If arg5 is NULL, the name of the appropriate anonymous virtual memory areas will be reset. The name can contain only printable ascii characters (including space), except '[',']','\','$' and '`'. This feature is available only if the kernel is built with the CONFIG_ANON_VMA_NAME option enabled. [surenb@google.com: docs: proc.rst: /proc/PID/maps: fix malformed table] Link: https://lkml.kernel.org/r/20211123185928.2513763-1-surenb@google.com [surenb: rebased over v5.15-rc6, replaced userpointer with a kernel copy, added input sanitization and CONFIG_ANON_VMA_NAME config. The bulk of the work here was done by Colin Cross, therefore, with his permission, keeping him as the author] Link: https://lkml.kernel.org/r/20211019215511.3771969-2-surenb@google.com Signed-off-by: Colin Cross <ccross@google.com> Signed-off-by: Suren Baghdasaryan <surenb@google.com> Reviewed-by: Kees Cook <keescook@chromium.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Cyrill Gorcunov <gorcunov@openvz.org> Cc: Dave Hansen <dave.hansen@intel.com> Cc: David Rientjes <rientjes@google.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Hugh Dickins <hughd@google.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jan Glauber <jan.glauber@gmail.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: John Stultz <john.stultz@linaro.org> Cc: Mel Gorman <mgorman@suse.de> Cc: Minchan Kim <minchan@kernel.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rob Landley <rob@landley.net> Cc: "Serge E. Hallyn" <serge.hallyn@ubuntu.com> Cc: Shaohua Li <shli@fusionio.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-01-13doc: document new CephFS mount device syntaxVenky Shankar
Signed-off-by: Venky Shankar <vshankar@redhat.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Ilya Dryomov <idryomov@gmail.com>