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2019-03-28vfs: Update mount API docsDavid Howells
Update the mount API docs to reflect recent changes to the code. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-03-15Merge tag '5.1-rc-smb3' of git://git.samba.org/sfrench/cifs-2.6Linus Torvalds
Pull more smb3 updates from Steve French: "Various tracing and debugging improvements, crediting fixes, some cleanup, and important fallocate fix (fixes three xfstests) and lock fix. Summary: - Various additional dynamic tracing tracepoints - Debugging improvements (including ability to query the server via SMB3 fsctl from userspace tools which can help with stats and debugging) - One minor performance improvement (root directory inode caching) - Crediting (SMB3 flow control) fixes - Some cleanup (docs and to mknod) - Important fixes: one to smb3 implementation of fallocate zero range (which fixes three xfstests) and a POSIX lock fix" * tag '5.1-rc-smb3' of git://git.samba.org/sfrench/cifs-2.6: (22 commits) CIFS: fix POSIX lock leak and invalid ptr deref SMB3: Allow SMB3 FSCTL queries to be sent to server from tools cifs: fix incorrect handling of smb2_set_sparse() return in smb3_simple_falloc smb2: fix typo in definition of a few error flags CIFS: make mknod() an smb_version_op cifs: minor documentation updates cifs: remove unused value pointed out by Coverity SMB3: passthru query info doesn't check for SMB3 FSCTL passthru smb3: add dynamic tracepoints for simple fallocate and zero range cifs: fix smb3_zero_range so it can expand the file-size when required cifs: add SMB2_ioctl_init/free helpers to be used with compounding smb3: Add dynamic trace points for various compounded smb3 ops cifs: cache FILE_ALL_INFO for the shared root handle smb3: display volume serial number for shares in /proc/fs/cifs/DebugData cifs: simplify how we handle credits in compound_send_recv() smb3: add dynamic tracepoint for timeout waiting for credits smb3: display security information in /proc/fs/cifs/DebugData more accurately cifs: add a timeout argument to wait_for_free_credits cifs: prevent starvation in wait_for_free_credits for multi-credit requests cifs: wait_for_free_credits() make it possible to wait for >=1 credits ...
2019-03-15Merge tag 'f2fs-for-5.1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs Pull f2fs updates from Jaegeuk Kim: "We've continued mainly to fix bugs in this round, as f2fs has been shipped in more devices. Especially, we've focused on stabilizing checkpoint=disable feature, and provided some interfaces for QA. Enhancements: - expose FS_NOCOW_FL for pin_file - run discard jobs at unmount time with timeout - tune discarding thread to avoid idling which consumes power - some checking codes to address vulnerabilities - give random value to i_generation - shutdown with more flags for QA Bug fixes: - clean up stale objects when mount is failed along with checkpoint=disable - fix system being stuck due to wrong count by atomic writes - handle some corrupted disk cases - fix a deadlock in f2fs_read_inline_dir We've also added some minor build error fixes and clean-up patches" * tag 'f2fs-for-5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (53 commits) f2fs: set pin_file under CAP_SYS_ADMIN f2fs: fix to avoid deadlock in f2fs_read_inline_dir() f2fs: fix to adapt small inline xattr space in __find_inline_xattr() f2fs: fix to do sanity check with inode.i_inline_xattr_size f2fs: give some messages for inline_xattr_size f2fs: don't trigger read IO for beyond EOF page f2fs: fix to add refcount once page is tagged PG_private f2fs: remove wrong comment in f2fs_invalidate_page() f2fs: fix to use kvfree instead of kzfree f2fs: print more parameters in trace_f2fs_map_blocks f2fs: trace f2fs_ioc_shutdown f2fs: fix to avoid deadlock of atomic file operations f2fs: fix to dirty inode for i_mode recovery f2fs: give random value to i_generation f2fs: no need to take page lock in readdir f2fs: fix to update iostat correctly in IPU path f2fs: fix encrypted page memory leak f2fs: make fault injection covering __submit_flush_wait() f2fs: fix to retry fill_super only if recovery failed f2fs: silence VM_WARN_ON_ONCE in mempool_alloc ...
2019-03-14cifs: minor documentation updatesSteve French
Also updated a comment describing use of the GlobalMid_Lock Signed-off-by: Steve French <stfrench@microsoft.com>
2019-03-12Merge tag 'ceph-for-5.1-rc1' of git://github.com/ceph/ceph-clientLinus Torvalds
Pull ceph updates from Ilya Dryomov: "The highlights are: - rbd will now ignore discards that aren't aligned and big enough to actually free up some space (myself). This is controlled by the new alloc_size map option and can be disabled if needed. - support for rbd deep-flatten feature (myself). Deep-flatten allows "rbd flatten" to fully disconnect the clone image and its snapshots from the parent and make the parent snapshot removable. - a new round of cap handling improvements (Zheng Yan). The kernel client should now be much more prompt about releasing its caps and it is possible to put a limit on the number of caps held. - support for getting ceph.dir.pin extended attribute (Zheng Yan)" * tag 'ceph-for-5.1-rc1' of git://github.com/ceph/ceph-client: (26 commits) Documentation: modern versions of ceph are not backed by btrfs rbd: advertise support for RBD_FEATURE_DEEP_FLATTEN rbd: whole-object write and zeroout should copyup when snapshots exist rbd: copyup with an empty snapshot context (aka deep-copyup) rbd: introduce rbd_obj_issue_copyup_ops() rbd: stop copying num_osd_ops in rbd_obj_issue_copyup() rbd: factor out __rbd_osd_req_create() rbd: clear ->xferred on error from rbd_obj_issue_copyup() rbd: remove experimental designation from kernel layering ceph: add mount option to limit caps count ceph: periodically trim stale dentries ceph: delete stale dentry when last reference is dropped ceph: remove dentry_lru file from debugfs ceph: touch existing cap when handling reply ceph: pass inclusive lend parameter to filemap_write_and_wait_range() rbd: round off and ignore discards that are too small rbd: handle DISCARD and WRITE_ZEROES separately rbd: get rid of obj_req->obj_request_count libceph: use struct_size() for kmalloc() in crush_decode() ceph: send cap releases more aggressively ...
2019-03-12Merge branch 'work.mount' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs mount infrastructure updates from Al Viro: "The rest of core infrastructure; no new syscalls in that pile, but the old parts are switched to new infrastructure. At that point conversions of individual filesystems can happen independently; some are done here (afs, cgroup, procfs, etc.), there's also a large series outside of that pile dealing with NFS (quite a bit of option-parsing stuff is getting used there - it's one of the most convoluted filesystems in terms of mount-related logics), but NFS bits are the next cycle fodder. It got seriously simplified since the last cycle; documentation is probably the weakest bit at the moment - I considered dropping the commit introducing Documentation/filesystems/mount_api.txt (cutting the size increase by quarter ;-), but decided that it would be better to fix it up after -rc1 instead. That pile allows to do followup work in independent branches, which should make life much easier for the next cycle. fs/super.c size increase is unpleasant; there's a followup series that allows to shrink it considerably, but I decided to leave that until the next cycle" * 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (41 commits) afs: Use fs_context to pass parameters over automount afs: Add fs_context support vfs: Add some logging to the core users of the fs_context log vfs: Implement logging through fs_context vfs: Provide documentation for new mount API vfs: Remove kern_mount_data() hugetlbfs: Convert to fs_context cpuset: Use fs_context kernfs, sysfs, cgroup, intel_rdt: Support fs_context cgroup: store a reference to cgroup_ns into cgroup_fs_context cgroup1_get_tree(): separate "get cgroup_root to use" into a separate helper cgroup_do_mount(): massage calling conventions cgroup: stash cgroup_root reference into cgroup_fs_context cgroup2: switch to option-by-option parsing cgroup1: switch to option-by-option parsing cgroup: take options parsing into ->parse_monolithic() cgroup: fold cgroup1_mount() into cgroup1_get_tree() cgroup: start switching to fs_context ipc: Convert mqueue fs to fs_context proc: Add fs_context support to procfs ...
2019-03-09Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsiLinus Torvalds
Pull SCSI updates from James Bottomley: "This is mostly update of the usual drivers: arcmsr, qla2xxx, lpfc, hisi_sas, target/iscsi and target/core. Additionally Christoph refactored gdth as part of the dma changes. The major mid-layer change this time is the removal of bidi commands and with them the whole of the osd/exofs driver and filesystem. This is a major simplification for block and mq in particular" * tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (240 commits) scsi: cxgb4i: validate tcp sequence number only if chip version <= T5 scsi: cxgb4i: get pf number from lldi->pf scsi: core: replace GFP_ATOMIC with GFP_KERNEL in scsi_scan.c scsi: mpt3sas: Add missing breaks in switch statements scsi: aacraid: Fix missing break in switch statement scsi: kill command serial number scsi: csiostor: drop serial_number usage scsi: mvumi: use request tag instead of serial_number scsi: dpt_i2o: remove serial number usage scsi: st: osst: Remove negative constant left-shifts scsi: ufs-bsg: Allow reading descriptors scsi: ufs: Allow reading descriptor via raw upiu scsi: ufs-bsg: Change the calling convention for write descriptor scsi: ufs: Remove unused device quirks Revert "scsi: ufs: disable vccq if it's not needed by UFS device" scsi: megaraid_sas: Remove a bunch of set but not used variables scsi: clean obsolete return values of eh_timed_out scsi: sd: Optimal I/O size should be a multiple of physical block size scsi: MAINTAINERS: SCSI initiator and target tweaks scsi: fcoe: make use of fip_mode enum complete ...
2019-03-09Merge tag 'fscrypt-for-linus' of git://git.kernel.org/pub/scm/fs/fscrypt/fscryptLinus Torvalds
Pull fscrypt updates from Eric Biggers: "First: Ted, Jaegeuk, and I have decided to add me as a co-maintainer for fscrypt, and we're now using a shared git tree. So we've updated MAINTAINERS accordingly, and I'm doing the pull request this time. The actual changes for v5.1 are: - Remove the fs-specific kconfig options like CONFIG_EXT4_ENCRYPTION and make fscrypt support for all fscrypt-capable filesystems be controlled by CONFIG_FS_ENCRYPTION, similar to how CONFIG_QUOTA works. - Improve error code for rename() and link() into encrypted directories. - Various cleanups" * tag 'fscrypt-for-linus' of git://git.kernel.org/pub/scm/fs/fscrypt/fscrypt: MAINTAINERS: add Eric Biggers as an fscrypt maintainer fscrypt: return -EXDEV for incompatible rename or link into encrypted dir fscrypt: remove filesystem specific build config option f2fs: use IS_ENCRYPTED() to check encryption status ext4: use IS_ENCRYPTED() to check encryption status fscrypt: remove CRYPTO_CTR dependency
2019-03-09Merge tag 'docs-5.1' of git://git.lwn.net/linuxLinus Torvalds
Pull documentation updates from Jonathan Corbet: "A fairly routine cycle for docs - lots of typo fixes, some new documents, and more translations. There's also some LICENSES adjustments from Thomas" * tag 'docs-5.1' of git://git.lwn.net/linux: (74 commits) docs: Bring some order to filesystem documentation Documentation/locking/lockdep: Drop last two chars of sample states doc: rcu: Suspicious RCU usage is a warning docs: driver-api: iio: fix errors in documentation Documentation/process/howto: Update for 4.x -> 5.x versioning docs: Explicitly state that the 'Fixes:' tag shouldn't split lines doc: security: Add kern-doc for lsm_hooks.h doc: sctp: Merge and clean up rst files Docs: Correct /proc/stat path scripts/spdxcheck.py: fix C++ comment style detection doc: fix typos in license-rules.rst Documentation: fix admin-guide/README.rst minimum gcc version requirement doc: process: complete removal of info about -git patches doc: translations: sync translations 'remove info about -git patches' perf-security: wrap paragraphs on 72 columns perf-security: elaborate on perf_events/Perf privileged users perf-security: document collected perf_events/Perf data categories perf-security: document perf_events/Perf resource control sysfs.txt: add note on available attribute macros docs: kernel-doc: typo "if ... if" -> "if ... is" ...
2019-03-08Merge tag 'for-5.1/block-20190302' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull block layer updates from Jens Axboe: "Not a huge amount of changes in this round, the biggest one is that we finally have Mings multi-page bvec support merged. Apart from that, this pull request contains: - Small series that avoids quiescing the queue for sysfs changes that match what we currently have (Aleksei) - Series of bcache fixes (via Coly) - Series of lightnvm fixes (via Mathias) - NVMe pull request from Christoph. Nothing major, just SPDX/license cleanups, RR mp policy (Hannes), and little fixes (Bart, Chaitanya). - BFQ series (Paolo) - Save blk-mq cpu -> hw queue mapping, removing a pointer indirection for the fast path (Jianchao) - fops->iopoll() added for async IO polling, this is a feature that the upcoming io_uring interface will use (Christoph, me) - Partition scan loop fixes (Dongli) - mtip32xx conversion from managed resource API (Christoph) - cdrom registration race fix (Guenter) - MD pull from Song, two minor fixes. - Various documentation fixes (Marcos) - Multi-page bvec feature. This brings a lot of nice improvements with it, like more efficient splitting, larger IOs can be supported without growing the bvec table size, and so on. (Ming) - Various little fixes to core and drivers" * tag 'for-5.1/block-20190302' of git://git.kernel.dk/linux-block: (117 commits) block: fix updating bio's front segment size block: Replace function name in string with __func__ nbd: propagate genlmsg_reply return code floppy: remove set but not used variable 'q' null_blk: fix checking for REQ_FUA block: fix NULL pointer dereference in register_disk fs: fix guard_bio_eod to check for real EOD errors blk-mq: use HCTX_TYPE_DEFAULT but not 0 to index blk_mq_tag_set->map block: optimize bvec iteration in bvec_iter_advance block: introduce mp_bvec_for_each_page() for iterating over page block: optimize blk_bio_segment_split for single-page bvec block: optimize __blk_segment_map_sg() for single-page bvec block: introduce bvec_nth_page() iomap: wire up the iopoll method block: add bio_set_polled() helper block: wire up block device iopoll method fs: add an iopoll method to struct file_operations loop: set GENHD_FL_NO_PART_SCAN after blkdev_reread_part() loop: do not print warn message if partition scan is successful block: bounce: make sure that bvec table is updated ...
2019-03-06docs: Bring some order to filesystem documentationJonathan Corbet
Documentation/filesystems is, like much of the rest of the kernel's documentation, a jumble of unorganized information. Split the documentation into categories and try to bring some order to the top-level index.rst files. No text changes other than a few section-introductory blurbs; this is all just moving stuff around. Cc: linux-fsdevel@vger.kernel.org Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-03-05f2fs: fix to document inline_xattr_size optionChao Yu
We missed to add document for inline_xattr_size mount option in f2fs.txt, add it. Signed-off-by: Chao Yu <yuchao0@huawei.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2019-03-05Documentation: modern versions of ceph are not backed by btrfsJeff Layton
[ Update the links too. ] Signed-off-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2019-03-05ceph: add mount option to limit caps countYan, Zheng
If number of caps exceed the limit, ceph_trim_dentires() also trim dentries with valid leases. Trimming dentry releases references to associated inode, which may evict inode and release caps. By default, there is no limit for caps count. Signed-off-by: "Yan, Zheng" <zyan@redhat.com> Reviewed-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2019-02-28vfs: Provide documentation for new mount APIDavid Howells
Provide documentation for the new mount API. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-02-24fs: add an iopoll method to struct file_operationsChristoph Hellwig
This new methods is used to explicitly poll for I/O completion for an iocb. It must be called for any iocb submitted asynchronously (that is with a non-null ki_complete) which has the IOCB_HIPRI flag set. The method is assisted by a new ki_cookie field in struct iocb to store the polling cookie. Reviewed-by: Hannes Reinecke <hare@suse.com> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-02-17sysfs.txt: add note on available attribute macrosNicholas Mc Guire
The common cases of attributes wrappers should probably be using the __ATTR_XXX macros to make code more concise and readable but the current sysfs.txt does not point developers to those convenience macros. Further there is no note in sysfs.txt currently explaining why trying to set a sysfs file to mode 0666 will fail respectively revert to 0664. Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-02-11xfs: Introduce XFS_PTAG_VERIFIER_ERROR panic maskMarco Benatto
Currently we have a few PTAGs in place allowing us to transform a filesystem error in a BUG() call. However, we don't have a panic tag for corrupt metadata, so introduce XFS_PTAG_VERIFIER_ERROR so that the administrator can use the fs.xfs.panic_mask sysctl knob to convert any error detected by buffer verifiers into a kernel panic. Signed-off-by: Marco Benatto <mbenatto@redhat.com> Reviewed-by: Eric Sandeen <sandeen@redhat.com> [darrick: light editing of commit message] Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2019-02-05scsi: fs: remove exofsChristoph Hellwig
This was an example for using the SCSI OSD protocol, which we're trying to remove. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2019-01-23fscrypt: return -EXDEV for incompatible rename or link into encrypted dirEric Biggers
Currently, trying to rename or link a regular file, directory, or symlink into an encrypted directory fails with EPERM when the source file is unencrypted or is encrypted with a different encryption policy, and is on the same mountpoint. It is correct for the operation to fail, but the choice of EPERM breaks tools like 'mv' that know to copy rather than rename if they see EXDEV, but don't know what to do with EPERM. Our original motivation for EPERM was to encourage users to securely handle their data. Encrypting files by "moving" them into an encrypted directory can be insecure because the unencrypted data may remain in free space on disk, where it can later be recovered by an attacker. It's much better to encrypt the data from the start, or at least try to securely delete the source data e.g. using the 'shred' program. However, the current behavior hasn't been effective at achieving its goal because users tend to be confused, hack around it, and complain; see e.g. https://github.com/google/fscrypt/issues/76. And in some cases it's actually inconsistent or unnecessary. For example, 'mv'-ing files between differently encrypted directories doesn't work even in cases where it can be secure, such as when in userspace the same passphrase protects both directories. Yet, you *can* already 'mv' unencrypted files into an encrypted directory if the source files are on a different mountpoint, even though doing so is often insecure. There are probably better ways to teach users to securely handle their files. For example, the 'fscrypt' userspace tool could provide a command that migrates unencrypted files into an encrypted directory, acting like 'shred' on the source files and providing appropriate warnings depending on the type of the source filesystem and disk. Receiving errors on unimportant files might also force some users to disable encryption, thus making the behavior counterproductive. It's desirable to make encryption as unobtrusive as possible. Therefore, change the error code from EPERM to EXDEV so that tools looking for EXDEV will fall back to a copy. This, of course, doesn't prevent users from still doing the right things to securely manage their files. Note that this also matches the behavior when a file is renamed between two project quota hierarchies; so there's precedent for using EXDEV for things other than mountpoints. xfstests generic/398 will require an update with this change. [Rewritten from an earlier patch series by Michael Halcrow.] Cc: Michael Halcrow <mhalcrow@google.com> Cc: Joe Richey <joerichey@google.com> Signed-off-by: Eric Biggers <ebiggers@google.com>
2019-01-23fscrypt: remove filesystem specific build config optionChandan Rajendra
In order to have a common code base for fscrypt "post read" processing for all filesystems which support encryption, this commit removes filesystem specific build config option (e.g. CONFIG_EXT4_FS_ENCRYPTION) and replaces it with a build option (i.e. CONFIG_FS_ENCRYPTION) whose value affects all the filesystems making use of fscrypt. Reviewed-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Chandan Rajendra <chandan@linux.vnet.ibm.com> Signed-off-by: Eric Biggers <ebiggers@google.com>
2019-01-14Documentation/filesystems: add binderfsChristian Brauner
This documents the Android binderfs filesystem used to dynamically add and remove binder devices that are private to each instance. Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com> [jc: tweaked markup and added to filesystems/index.rst] Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-01-08Documentation: driver core: remove use of BUS_ATTRGreg Kroah-Hartman
We are getting rid of the "raw" BUS_ATTR() macro, so fix up the documentation to not refer to it anymore. Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-07Documentation/filesystems: fix title underline lengths in path-lookup.rstRandy Dunlap
Fix Sphinx warnings in path-lookup.rst: Documentation/filesystems/path-lookup.rst:347: WARNING: Title underline too short. Documentation/filesystems/path-lookup.rst:358: WARNING: Title underline too short. [...] Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Acked-by: NeilBrown <neilb@suse.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-01-06Merge tag 'fscrypt_for_linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tytso/fscrypt Pull fscrypt updates from Ted Ts'o: "Add Adiantum support for fscrypt" * tag 'fscrypt_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/fscrypt: fscrypt: add Adiantum support
2019-01-06fscrypt: add Adiantum supportEric Biggers
Add support for the Adiantum encryption mode to fscrypt. Adiantum is a tweakable, length-preserving encryption mode with security provably reducible to that of XChaCha12 and AES-256, subject to a security bound. It's also a true wide-block mode, unlike XTS. See the paper "Adiantum: length-preserving encryption for entry-level processors" (https://eprint.iacr.org/2018/720.pdf) for more details. Also see commit 059c2a4d8e16 ("crypto: adiantum - add Adiantum support"). On sufficiently long messages, Adiantum's bottlenecks are XChaCha12 and the NH hash function. These algorithms are fast even on processors without dedicated crypto instructions. Adiantum makes it feasible to enable storage encryption on low-end mobile devices that lack AES instructions; currently such devices are unencrypted. On ARM Cortex-A7, on 4096-byte messages Adiantum encryption is about 4 times faster than AES-256-XTS encryption; decryption is about 5 times faster. In fscrypt, Adiantum is suitable for encrypting both file contents and names. With filenames, it fixes a known weakness: when two filenames in a directory share a common prefix of >= 16 bytes, with CTS-CBC their encrypted filenames share a common prefix too, leaking information. Adiantum does not have this problem. Since Adiantum also accepts long tweaks (IVs), it's also safe to use the master key directly for Adiantum encryption rather than deriving per-file keys, provided that the per-file nonce is included in the IVs and the master key isn't used for any other encryption mode. This configuration saves memory and improves performance. A new fscrypt policy flag is added to allow users to opt-in to this configuration. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-01-05Merge tag 'docs-5.0-fixes' of git://git.lwn.net/linuxLinus Torvalds
Pull documentation fixes from Jonathan Corbet: "A handful of late-arriving documentation fixes" * tag 'docs-5.0-fixes' of git://git.lwn.net/linux: doc: filesystems: fix bad references to nonexistent ext4.rst file Documentation/admin-guide: update URL of LKML information link Docs/kernel-api.rst: Remove blk-tag.c reference
2019-01-03doc: filesystems: fix bad references to nonexistent ext4.rst fileOtto Sabart
The ext4.rst file does not exist anymore. This patch changes all references to point to the whole ext4 directory. Fixes: d3091215921b ("docs: move ext4 administrative docs to admin-guide/") Signed-off-by: Otto Sabart <ottosabart@seberm.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-01-02Merge tag '4.21-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6Linus Torvalds
Pull cifs updates from Steve French: - four fixes for stable - improvements to DFS including allowing failover to alternate targets - some small performance improvements * tag '4.21-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6: (39 commits) cifs: update internal module version number cifs: we can not use small padding iovs together with encryption cifs: Minor Kconfig clarification cifs: Always resolve hostname before reconnecting cifs: Add support for failover in cifs_reconnect_tcon() cifs: Add support for failover in smb2_reconnect() cifs: Only free DFS target list if we actually got one cifs: start DFS cache refresher in cifs_mount() cifs: Use GFP_ATOMIC when a lock is held in cifs_mount() cifs: Add support for failover in cifs_reconnect() cifs: Add support for failover in cifs_mount() cifs: remove set but not used variable 'sep' cifs: Make use of DFS cache to get new DFS referrals cifs: minor updates to documentation cifs: check kzalloc return cifs: remove set but not used variable 'server' cifs: Use kzfree() to free password cifs: Fix to use kmem_cache_free() instead of kfree() cifs: update for current_kernel_time64() removal cifs: Add DFS cache routines ...
2018-12-29Merge tag 'docs-5.0' of git://git.lwn.net/linuxLinus Torvalds
Pull documentation update from Jonathan Corbet: "A fairly normal cycle for documentation stuff. We have a new document on perf security, more Italian translations, more improvements to the memory-management docs, improvements to the pathname lookup documentation, and the usual array of smaller fixes. As is often the case, there are a few reaches outside of Documentation/ to adjust kerneldoc comments" * tag 'docs-5.0' of git://git.lwn.net/linux: (38 commits) docs: improve pathname-lookup document structure configfs: fix wrong name of struct in documentation docs/mm-api: link slab_common.c to "The Slab Cache" section slab: make kmem_cache_create{_usercopy} description proper kernel-doc doc:process: add links where missing docs/core-api: make mm-api.rst more structured x86, boot: documentation whitespace fixup Documentation: devres: note checking needs when converting doc:it: add some process/* translations doc:it: fixes in process/1.Intro Documentation: convert path-lookup from markdown to resturctured text Documentation/admin-guide: update admin-guide index.rst Documentation/admin-guide: introduce perf-security.rst file scripts/kernel-doc: Fix struct and struct field attribute processing Documentation: dev-tools: Fix typos in index.rst Correct gen_init_cpio tool's documentation Document /proc/pid PID reuse behavior Documentation: update path-lookup.md for parallel lookups Documentation: Use "while" instead of "whilst" dmaengine: Add mailing list address to the documentation ...
2018-12-28mm, proc: report PR_SET_THP_DISABLE in procMichal Hocko
David Rientjes has reported that commit 1860033237d4 ("mm: make PR_SET_THP_DISABLE immediately active") has changed the way how we report THPable VMAs to the userspace. Their monitoring tool is triggering false alarms on PR_SET_THP_DISABLE tasks because it considers an insufficient THP usage as a memory fragmentation resp. memory pressure issue. Before the said commit each newly created VMA inherited VM_NOHUGEPAGE flag and that got exposed to the userspace via /proc/<pid>/smaps file. This implementation had its downsides as explained in the commit message but it is true that the userspace doesn't have any means to query for the process wide THP enabled/disabled status. PR_SET_THP_DISABLE is a process wide flag so it makes a lot of sense to export in the process wide context rather than per-vma. Introduce a new field to /proc/<pid>/status which export this status. If PR_SET_THP_DISABLE is used then it reports false same as when the THP is not compiled in. It doesn't consider the global THP status because we already export that information via sysfs Link: http://lkml.kernel.org/r/20181211143641.3503-4-mhocko@kernel.org Fixes: 1860033237d4 ("mm: make PR_SET_THP_DISABLE immediately active") Signed-off-by: Michal Hocko <mhocko@suse.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Reported-by: David Rientjes <rientjes@google.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Jan Kara <jack@suse.cz> Cc: Mike Rapoport <rppt@linux.ibm.com> Cc: Paul Oppenheimer <bepvte@gmail.com> Cc: William Kucharski <william.kucharski@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-12-28mm, thp, proc: report THP eligibility for each vmaMichal Hocko
Userspace falls short when trying to find out whether a specific memory range is eligible for THP. There are usecases that would like to know that http://lkml.kernel.org/r/alpine.DEB.2.21.1809251248450.50347@chino.kir.corp.google.com : This is used to identify heap mappings that should be able to fault thp : but do not, and they normally point to a low-on-memory or fragmentation : issue. The only way to deduce this now is to query for hg resp. nh flags and confronting the state with the global setting. Except that there is also PR_SET_THP_DISABLE that might change the picture. So the final logic is not trivial. Moreover the eligibility of the vma depends on the type of VMA as well. In the past we have supported only anononymous memory VMAs but things have changed and shmem based vmas are supported as well these days and the query logic gets even more complicated because the eligibility depends on the mount option and another global configuration knob. Simplify the current state and report the THP eligibility in /proc/<pid>/smaps for each existing vma. Reuse transparent_hugepage_enabled for this purpose. The original implementation of this function assumes that the caller knows that the vma itself is supported for THP so make the core checks into __transparent_hugepage_enabled and use it for existing callers. __show_smap just use the new transparent_hugepage_enabled which also checks the vma support status (please note that this one has to be out of line due to include dependency issues). [mhocko@kernel.org: fix oops with NULL ->f_mapping] Link: http://lkml.kernel.org/r/20181224185106.GC16738@dhcp22.suse.cz Link: http://lkml.kernel.org/r/20181211143641.3503-3-mhocko@kernel.org Signed-off-by: Michal Hocko <mhocko@suse.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Dan Williams <dan.j.williams@intel.com> Cc: David Rientjes <rientjes@google.com> Cc: Jan Kara <jack@suse.cz> Cc: Mike Rapoport <rppt@linux.ibm.com> Cc: Paul Oppenheimer <bepvte@gmail.com> Cc: William Kucharski <william.kucharski@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-12-28mm, proc: be more verbose about unstable VMA flags in /proc/<pid>/smapsMichal Hocko
Patch series "THP eligibility reporting via proc". This series of three patches aims at making THP eligibility reporting much more robust and long term sustainable. The trigger for the change is a regression report [2] and the long follow up discussion. In short the specific application didn't have good API to query whether a particular mapping can be backed by THP so it has used VMA flags to workaround that. These flags represent a deep internal state of VMAs and as such they should be used by userspace with a great deal of caution. A similar has happened for [3] when users complained that VM_MIXEDMAP is no longer set on DAX mappings. Again a lack of a proper API led to an abuse. The first patch in the series tries to emphasise that that the semantic of flags might change and any application consuming those should be really careful. The remaining two patches provide a more suitable interface to address [2] and provide a consistent API to query the THP status both for each VMA and process wide as well. [1] http://lkml.kernel.org/r/20181120103515.25280-1-mhocko@kernel.org [2] http://lkml.kernel.org/r/http://lkml.kernel.org/r/alpine.DEB.2.21.1809241054050.224429@chino.kir.corp.google.com [3] http://lkml.kernel.org/r/20181002100531.GC4135@quack2.suse.cz This patch (of 3): Even though vma flags exported via /proc/<pid>/smaps are explicitly documented to be not guaranteed for future compatibility the warning doesn't go far enough because it doesn't mention semantic changes to those flags. And they are important as well because these flags are a deep implementation internal to the MM code and the semantic might change at any time. Let's consider two recent examples: http://lkml.kernel.org/r/20181002100531.GC4135@quack2.suse.cz : commit e1fb4a086495 "dax: remove VM_MIXEDMAP for fsdax and device dax" has : removed VM_MIXEDMAP flag from DAX VMAs. Now our testing shows that in the : mean time certain customer of ours started poking into /proc/<pid>/smaps : and looks at VMA flags there and if VM_MIXEDMAP is missing among the VMA : flags, the application just fails to start complaining that DAX support is : missing in the kernel. http://lkml.kernel.org/r/alpine.DEB.2.21.1809241054050.224429@chino.kir.corp.google.com : Commit 1860033237d4 ("mm: make PR_SET_THP_DISABLE immediately active") : introduced a regression in that userspace cannot always determine the set : of vmas where thp is ineligible. : Userspace relies on the "nh" flag being emitted as part of /proc/pid/smaps : to determine if a vma is eligible to be backed by hugepages. : Previous to this commit, prctl(PR_SET_THP_DISABLE, 1) would cause thp to : be disabled and emit "nh" as a flag for the corresponding vmas as part of : /proc/pid/smaps. After the commit, thp is disabled by means of an mm : flag and "nh" is not emitted. : This causes smaps parsing libraries to assume a vma is eligible for thp : and ends up puzzling the user on why its memory is not backed by thp. In both cases userspace was relying on a semantic of a specific VMA flag. The primary reason why that happened is a lack of a proper interface. While this has been worked on and it will be fixed properly, it seems that our wording could see some refinement and be more vocal about semantic aspect of these flags as well. Link: http://lkml.kernel.org/r/20181211143641.3503-2-mhocko@kernel.org Signed-off-by: Michal Hocko <mhocko@suse.com> Acked-by: Jan Kara <jack@suse.cz> Acked-by: Dan Williams <dan.j.williams@intel.com> Acked-by: David Rientjes <rientjes@google.com> Acked-by: Mike Rapoport <rppt@linux.ibm.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Dan Williams <dan.j.williams@intel.com> Cc: David Rientjes <rientjes@google.com> Cc: Paul Oppenheimer <bepvte@gmail.com> Cc: William Kucharski <william.kucharski@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-12-28cifs: minor updates to documentationSteve French
Update cifs "TODO" file. Signed-off-by: Steve French <stfrench@microsoft.com>
2018-12-20docs: improve pathname-lookup document structureNeilBrown
Get rid of some unneeded structural elements around the new (to RST) pathname-lookup document. Signed-off-by: NeilBrown <neilb@suse.com> [ jc: grabbed from email and changelog added ] Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2018-12-20configfs: fix wrong name of struct in documentationHelen Koike
The name of the struct is configfs_bin_attribute instead of configfs_attribute Signed-off-by: Helen Koike <helen.koike@collabora.com> Fixes: 03607ace807b ("configfs: implement binary attributes") Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2018-12-06Documentation: convert path-lookup from markdown to resturctured textNeilBrown
This allows the document to be integrated with the main documentation tree. Changes include: - rename from .md to .rst - use `` for code, not single ` - use correct sub-section marking - fix indented blocks, both code and non-code - fix external-link markup Signed-off-by: NeilBrown <neilb@suse.com> [jc: changed the toctree organization a bit] Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2018-11-20Document /proc/pid PID reuse behaviorDaniel Colascione
State explicitly that holding a /proc/pid file descriptor open does not reserve the PID. Also note that in the event of PID reuse, these open file descriptors refer to the old, now-dead process, and not the new one that happens to be named the same numeric PID. Signed-off-by: Daniel Colascione <dancol@google.com> Acked-by: Michal Hocko <mhocko@suse.com> Reviewed-by: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2018-11-20Documentation: update path-lookup.md for parallel lookupsNeilBrown
Since this document was written, i_mutex has been replace with i_rwsem, and shared locks are utilized to allow lookups in the one directory to happen in parallel. So replace i_mutex with i_rwsem, and explain how this is used for parallel lookups. Signed-off-by: NeilBrown <neilb@suse.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2018-11-20Documentation: Use "while" instead of "whilst"Will Deacon
Whilst making an unrelated change to some Documentation, Linus sayeth: | Afaik, even in Britain, "whilst" is unusual and considered more | formal, and "while" is the common word. | | [...] | | Can we just admit that we work with computers, and we don't need to | use þe eald Englisc spelling of words that most of the world never | uses? dictionary.com refers to the word as "Chiefly British", which is probably an undesirable attribute for technical documentation. Replace all occurrences under Documentation/ with "while". Cc: David Howells <dhowells@redhat.com> Cc: Liam Girdwood <lgirdwood@gmail.com> Cc: Chris Wilson <chris@chris-wilson.co.uk> Cc: Michael Halcrow <mhalcrow@google.com> Cc: Jonathan Corbet <corbet@lwn.net> Reported-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2018-11-07Documentation: fix spelling mistake, EACCESS -> EACCESColin Ian King
Trivial fix to a spelling mistake of the error access name EACCESS, rename to EACCES Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2018-11-07Documentation/proc.txt: Add 2 missing fields for /proc/<pid>/statusWaiman Long
It was found that two of the fields in the /proc/<pid>/status file were missing - CapAmb & Speculation_Store_Bypass. They are now added to the proc.txt documentation file. v2: Update the example as well. Signed-off-by: Waiman Long <longman@redhat.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2018-11-04Merge tag 'tags/upstream-4.20-rc1' of git://git.infradead.org/linux-ubifsLinus Torvalds
Pull UBIFS updates from Richard Weinberger: - Full filesystem authentication feature, UBIFS is now able to have the whole filesystem structure authenticated plus user data encrypted and authenticated. - Minor cleanups * tag 'tags/upstream-4.20-rc1' of git://git.infradead.org/linux-ubifs: (26 commits) ubifs: Remove unneeded semicolon Documentation: ubifs: Add authentication whitepaper ubifs: Enable authentication support ubifs: Do not update inode size in-place in authenticated mode ubifs: Add hashes and HMACs to default filesystem ubifs: authentication: Authenticate super block node ubifs: Create hash for default LPT ubfis: authentication: Authenticate master node ubifs: authentication: Authenticate LPT ubifs: Authenticate replayed journal ubifs: Add auth nodes to garbage collector journal head ubifs: Add authentication nodes to journal ubifs: authentication: Add hashes to index nodes ubifs: Add hashes to the tree node cache ubifs: Create functions to embed a HMAC in a node ubifs: Add helper functions for authentication support ubifs: Add separate functions to init/crc a node ubifs: Format changes for authentication support ubifs: Store read superblock node ubifs: Drop write_node ...
2018-11-02Merge tag 'xfs-4.20-merge-2' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linuxLinus Torvalds
Pull vfs dedup fixes from Dave Chinner: "This reworks the vfs data cloning infrastructure. We discovered many issues with these interfaces late in the 4.19 cycle - the worst of them (data corruption, setuid stripping) were fixed for XFS in 4.19-rc8, but a larger rework of the infrastructure fixing all the problems was needed. That rework is the contents of this pull request. Rework the vfs_clone_file_range and vfs_dedupe_file_range infrastructure to use a common .remap_file_range method and supply generic bounds and sanity checking functions that are shared with the data write path. The current VFS infrastructure has problems with rlimit, LFS file sizes, file time stamps, maximum filesystem file sizes, stripping setuid bits, etc and so they are addressed in these commits. We also introduce the ability for the ->remap_file_range methods to return short clones so that clones for vfs_copy_file_range() don't get rejected if the entire range can't be cloned. It also allows filesystems to sliently skip deduplication of partial EOF blocks if they are not capable of doing so without requiring errors to be thrown to userspace. Existing filesystems are converted to user the new remap_file_range method, and both XFS and ocfs2 are modified to make use of the new generic checking infrastructure" * tag 'xfs-4.20-merge-2' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: (28 commits) xfs: remove [cm]time update from reflink calls xfs: remove xfs_reflink_remap_range xfs: remove redundant remap partial EOF block checks xfs: support returning partial reflink results xfs: clean up xfs_reflink_remap_blocks call site xfs: fix pagecache truncation prior to reflink ocfs2: remove ocfs2_reflink_remap_range ocfs2: support partial clone range and dedupe range ocfs2: fix pagecache truncation prior to reflink ocfs2: truncate page cache for clone destination file before remapping vfs: clean up generic_remap_file_range_prep return value vfs: hide file range comparison function vfs: enable remap callers that can handle short operations vfs: plumb remap flags through the vfs dedupe functions vfs: plumb remap flags through the vfs clone functions vfs: make remap_file_range functions take and return bytes completed vfs: remap helper should update destination inode metadata vfs: pass remap flags to generic_remap_checks vfs: pass remap flags to generic_remap_file_range_prep vfs: combine the clone and dedupe into a single remap_file_range ...
2018-11-01Merge tag 'ovl-update-4.20' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs Pull overlayfs updates from Miklos Szeredi: "A mix of fixes and cleanups" * tag 'ovl-update-4.20' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs: ovl: automatically enable redirect_dir on metacopy=on ovl: check whiteout in ovl_create_over_whiteout() ovl: using posix_acl_xattr_size() to get size instead of posix_acl_to_xattr() ovl: abstract ovl_inode lock with a helper ovl: remove the 'locked' argument of ovl_nlink_{start,end} ovl: relax requirement for non null uuid of lower fs ovl: fold copy-up helpers into callers ovl: untangle copy up call chain ovl: relax permission checking on underlying layers ovl: fix recursive oi->lock in ovl_link() vfs: fix FIGETBSZ ioctl on an overlayfs file ovl: clean up error handling in ovl_get_tmpfile() ovl: fix error handling in ovl_verify_set_fh()
2018-11-01ovl: automatically enable redirect_dir on metacopy=onMiklos Szeredi
Current behavior is to automatically disable metacopy if redirect_dir is not enabled and proceed with the mount. If "metacopy=on" mount option was given, then this behavior can confuse the user: no mount failure, yet metacopy is disabled. This patch makes metacopy=on imply redirect_dir=on. The converse is also true: turning off full redirect with redirect_dir= {off|follow|nofollow} will disable metacopy. If both metacopy=on and redirect_dir={off|follow|nofollow} is specified, then mount will fail, since there's no way to correctly resolve the conflict. Reported-by: Daniel Walsh <dwalsh@redhat.com> Fixes: d5791044d2e5 ("ovl: Provide a mount option metacopy=on/off...") Cc: <stable@vger.kernel.org> # v4.19 Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2018-10-31Merge tag 'ceph-for-4.20-rc1' of git://github.com/ceph/ceph-clientLinus Torvalds
Pull ceph updates from Ilya Dryomov: "The highlights are: - a series that fixes some old memory allocation issues in libceph (myself). We no longer allocate memory in places where allocation failures cannot be handled and BUG when the allocation fails. - support for copy_file_range() syscall (Luis Henriques). If size and alignment conditions are met, it leverages RADOS copy-from operation. Otherwise, a local copy is performed. - a patch that reduces memory requirement of ceph_sync_read() from the size of the entire read to the size of one object (Zheng Yan). - fallocate() syscall is now restricted to FALLOC_FL_PUNCH_HOLE (Luis Henriques)" * tag 'ceph-for-4.20-rc1' of git://github.com/ceph/ceph-client: (25 commits) ceph: new mount option to disable usage of copy-from op ceph: support copy_file_range file operation libceph: support the RADOS copy-from operation ceph: add non-blocking parameter to ceph_try_get_caps() libceph: check reply num_data_items in setup_request_data() libceph: preallocate message data items libceph, rbd, ceph: move ceph_osdc_alloc_messages() calls libceph: introduce alloc_watch_request() libceph: assign cookies in linger_submit() libceph: enable fallback to ceph_msg_new() in ceph_msgpool_get() ceph: num_ops is off by one in ceph_aio_retry_work() libceph: no need to call osd_req_opcode_valid() in osd_req_encode_op() ceph: set timeout conditionally in __cap_delay_requeue libceph: don't consume a ref on pagelist in ceph_msg_data_add_pagelist() libceph: introduce ceph_pagelist_alloc() libceph: osd_req_op_cls_init() doesn't need to take opcode libceph: bump CEPH_MSG_MAX_DATA_LEN ceph: only allow punch hole mode in fallocate ceph: refactor ceph_sync_read() ceph: check if LOOKUPNAME request was aborted when filling trace ...
2018-10-30Merge tag 'nfsd-4.20' of git://linux-nfs.org/~bfields/linuxLinus Torvalds
Pull nfsd updates from Bruce Fields: "Olga added support for the NFSv4.2 asynchronous copy protocol. We already supported COPY, by copying a limited amount of data and then returning a short result, letting the client resend. The asynchronous protocol should offer better performance at the expense of some complexity. The other highlight is Trond's work to convert the duplicate reply cache to a red-black tree, and to move it and some other server caches to RCU. (Previously these have meant taking global spinlocks on every RPC) Otherwise, some RDMA work and miscellaneous bugfixes" * tag 'nfsd-4.20' of git://linux-nfs.org/~bfields/linux: (30 commits) lockd: fix access beyond unterminated strings in prints nfsd: Fix an Oops in free_session() nfsd: correctly decrement odstate refcount in error path svcrdma: Increase the default connection credit limit svcrdma: Remove try_module_get from backchannel svcrdma: Remove ->release_rqst call in bc reply handler svcrdma: Reduce max_send_sges nfsd: fix fall-through annotations knfsd: Improve lookup performance in the duplicate reply cache using an rbtree knfsd: Further simplify the cache lookup knfsd: Simplify NFS duplicate replay cache knfsd: Remove dead code from nfsd_cache_lookup SUNRPC: Simplify TCP receive code SUNRPC: Replace the cache_detail->hash_lock with a regular spinlock SUNRPC: Remove non-RCU protected lookup NFS: Fix up a typo in nfs_dns_ent_put NFS: Lockless DNS lookups knfsd: Lockless lookup of NFSv4 identities. SUNRPC: Lockless server RPCSEC_GSS context lookup knfsd: Allow lockless lookups of the exports ...
2018-10-30vfs: enable remap callers that can handle short operationsDarrick J. Wong
Plumb in a remap flag that enables the filesystem remap handler to shorten remapping requests for callers that can handle it. Now copy_file_range can report partial success (in case we run up against alignment problems, resource limits, etc.). We also enable CAN_SHORTEN for fideduperange to maintain existing userspace-visible behavior where xfs/btrfs shorten the dedupe range to avoid stale post-eof data exposure. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
2018-10-30vfs: make remap_file_range functions take and return bytes completedDarrick J. Wong
Change the remap_file_range functions to take a number of bytes to operate upon and return the number of bytes they operated on. This is a requirement for allowing fs implementations to return short clone/dedupe results to the user, which will enable us to obey resource limits in a graceful manner. A subsequent patch will enable copy_file_range to signal to the ->clone_file_range implementation that it can handle a short length, which will be returned in the function's return value. For now the short return is not implemented anywhere so the behavior won't change -- either copy_file_range manages to clone the entire range or it tries an alternative. Neither clone ioctl can take advantage of this, alas. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Dave Chinner <david@fromorbit.com>