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* driver core: clean up the logic to determine which /sys/dev/ directory to useGreg Kroah-Hartman2023-03-311-9/+0
| | | | | | | | | | | | | | | | | | | | | | When a dev_t is set in a struct device, an symlink in /sys/dev/ is created for it either under /sys/dev/block/ or /sys/dev/char/ depending on the device type. The logic to determine this would trigger off of the class of the object, and the kobj_type set in that location. But it turns out that this deep nesting isn't needed at all, as it's either a choice of block or "everything else" which is a char device. So make the logic a lot more simple and obvious, and remove the incorrect comments in the code that tried to document something that was not happening at all (it is impossible to set class->dev_kobj to NULL as the class core prevented that from happening. This removes the only place that class->dev_kobj was being used, so after this, it can be removed entirely. Acked-by: Rafael J. Wysocki <rafael@kernel.org> Link: https://lore.kernel.org/r/20230331093318.82288-4-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Merge tag 'driver-core-6.3-rc1' of ↵Linus Torvalds2023-02-241-8/+8
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core updates from Greg KH: "Here is the large set of driver core changes for 6.3-rc1. There's a lot of changes this development cycle, most of the work falls into two different categories: - fw_devlink fixes and updates. This has gone through numerous review cycles and lots of review and testing by lots of different devices. Hopefully all should be good now, and Saravana will be keeping a watch for any potential regression on odd embedded systems. - driver core changes to work to make struct bus_type able to be moved into read-only memory (i.e. const) The recent work with Rust has pointed out a number of areas in the driver core where we are passing around and working with structures that really do not have to be dynamic at all, and they should be able to be read-only making things safer overall. This is the contuation of that work (started last release with kobject changes) in moving struct bus_type to be constant. We didn't quite make it for this release, but the remaining patches will be finished up for the release after this one, but the groundwork has been laid for this effort. Other than that we have in here: - debugfs memory leak fixes in some subsystems - error path cleanups and fixes for some never-able-to-be-hit codepaths. - cacheinfo rework and fixes - Other tiny fixes, full details are in the shortlog All of these have been in linux-next for a while with no reported problems" [ Geert Uytterhoeven points out that that last sentence isn't true, and that there's a pending report that has a fix that is queued up - Linus ] * tag 'driver-core-6.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (124 commits) debugfs: drop inline constant formatting for ERR_PTR(-ERROR) OPP: fix error checking in opp_migrate_dentry() debugfs: update comment of debugfs_rename() i3c: fix device.h kernel-doc warnings dma-mapping: no need to pass a bus_type into get_arch_dma_ops() driver core: class: move EXPORT_SYMBOL_GPL() lines to the correct place Revert "driver core: add error handling for devtmpfs_create_node()" Revert "devtmpfs: add debug info to handle()" Revert "devtmpfs: remove return value of devtmpfs_delete_node()" driver core: cpu: don't hand-override the uevent bus_type callback. devtmpfs: remove return value of devtmpfs_delete_node() devtmpfs: add debug info to handle() driver core: add error handling for devtmpfs_create_node() driver core: bus: update my copyright notice driver core: bus: add bus_get_dev_root() function driver core: bus: constify bus_unregister() driver core: bus: constify some internal functions driver core: bus: constify bus_get_kset() driver core: bus: constify bus_register/unregister_notifier() driver core: remove private pointer from struct bus_type ...
| * Revert "devtmpfs: add debug info to handle()"Greg Kroah-Hartman2023-02-141-10/+2
| | | | | | | | | | | | | | | | | | | | This reverts commit 90a9d5ff225267b3376f73c19f21174e3b6d7746 as it is reported to cause boot regressions. Link: https://lore.kernel.org/r/Y+rSXg14z1Myd8Px@dev-arch.thelio-3990X Reported-by: Nathan Chancellor <nathan@kernel.org> Cc: Longlong Xia <xialonglong1@huawei.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * Revert "devtmpfs: remove return value of devtmpfs_delete_node()"Greg Kroah-Hartman2023-02-141-4/+4
| | | | | | | | | | | | | | | | | | | | This reverts commit 9d3fe6aa6b9517408064c7c3134187e8ec77dbf7 as it is reported to cause boot regressions. Link: https://lore.kernel.org/r/Y+rSXg14z1Myd8Px@dev-arch.thelio-3990X Reported-by: Nathan Chancellor <nathan@kernel.org> Cc: Longlong Xia <xialonglong1@huawei.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * devtmpfs: remove return value of devtmpfs_delete_node()Longlong Xia2023-02-111-4/+4
| | | | | | | | | | | | | | | | | | | | The only caller of device_del() does not check the return value. And there's nothing we can do when cleaning things up on a remove path. Let's make it a void function. Signed-off-by: Longlong Xia <xialonglong1@huawei.com> Link: https://lore.kernel.org/r/20230210095444.4067307-4-xialonglong1@huawei.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * devtmpfs: add debug info to handle()Longlong Xia2023-02-101-2/+10
| | | | | | | | | | | | | | | | | | Because handle() is the core function for processing devtmpfs requests, Let's add some debug info in handle() to help users know why failed. Signed-off-by: Longlong Xia <xialonglong1@huawei.com> Link: https://lore.kernel.org/r/20230210095444.4067307-3-xialonglong1@huawei.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * devtmpfs: convert to pr_fmtLonglong Xia2023-02-021-8/+8
| | | | | | | | | | | | | | | | | | Use the pr_fmt() macro to prefix all the output with "devtmpfs: ". while at it, convert printk(<LEVEL>) to pr_<level>(). Signed-off-by: Longlong Xia <xialonglong1@huawei.com> Link: https://lore.kernel.org/r/20230202033203.1239239-2-xialonglong1@huawei.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | fs: port vfs_*() helpers to struct mnt_idmapChristian Brauner2023-01-181-6/+6
|/ | | | | | | | | | | | | | | | | | | | | | | | | Convert to struct mnt_idmap. Last cycle we merged the necessary infrastructure in 256c8aed2b42 ("fs: introduce dedicated idmap type for mounts"). This is just the conversion to struct mnt_idmap. Currently we still pass around the plain namespace that was attached to a mount. This is in general pretty convenient but it makes it easy to conflate namespaces that are relevant on the filesystem with namespaces that are relevent on the mount level. Especially for non-vfs developers without detailed knowledge in this area this can be a potential source for bugs. Once the conversion to struct mnt_idmap is done all helpers down to the really low-level helpers will take a struct mnt_idmap argument instead of two namespace arguments. This way it becomes impossible to conflate the two eliminating the possibility of any bugs. All of the vfs and all filesystems only operate on struct mnt_idmap. Acked-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
* devtmpfs: fix the dangling pointer of global devtmpfsd threadYangxi Xiang2022-06-271-0/+1
| | | | | | | | | | | | | When the devtmpfs fails to mount, a dangling pointer still remains in global. Specifically, the err variable is passed by a pointer to the devtmpfsd. When the devtmpfsd exits, it sets the error and completes the setup_done. In this situation, the thread pointer is not set to null. After the devtmpfsd exited, the devtmpfs can wakes up the destroyed devtmpfsd thread by wake_up_process if a device change event comes. Signed-off-by: Yangxi Xiang <xyangxi5@gmail.com> Link: https://lore.kernel.org/r/20220627120409.11174-1-xyangxi5@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Merge tag 'driver-core-5.18-rc1' of ↵Linus Torvalds2022-03-281-2/+0
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core updates from Greg KH: "Here is the set of driver core changes for 5.18-rc1. Not much here, primarily it was a bunch of cleanups and small updates: - kobj_type cleanups for default_groups - documentation updates - firmware loader minor changes - component common helper added and take advantage of it in many drivers (the largest part of this pull request). All of these have been in linux-next for a while with no reported problems" * tag 'driver-core-5.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (54 commits) Documentation: update stable review cycle documentation drivers/base/dd.c : Remove the initial value of the global variable Documentation: update stable tree link Documentation: add link to stable release candidate tree devres: fix typos in comments Documentation: add note block surrounding security patch note samples/kobject: Use sysfs_emit instead of sprintf base: soc: Make soc_device_match() simpler and easier to read driver core: dd: fix return value of __setup handler driver core: Refactor sysfs and drv/bus remove hooks driver core: Refactor multiple copies of device cleanup scripts: get_abi.pl: Fix typo in help message kernfs: fix typos in comments kernfs: remove unneeded #if 0 guard ALSA: hda/realtek: Make use of the helper component_compare_dev_name video: omapfb: dss: Make use of the helper component_compare_dev power: supply: ab8500: Make use of the helper component_compare_dev ASoC: codecs: wcd938x: Make use of the helper component_compare/release_of iommu/mediatek: Make use of the helper component_compare/release_of drm: of: Make use of the helper component_release_of ...
| * devtmpfs: drop redundant fs parameters from internal fsAnthony Iliopoulos2022-02-041-2/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The internal_fs_type is mounted via vfs_kernel_mount() and is never registered as a filesystem, thus specifying the parameters is redundant as those params will not be validated by fs_validate_description(). Both {shmem,ramfs}_fs_parameters are anyway validated when those respective filesystems are first registered, so there is no reason to pass them to devtmpfs too, drop them. Reviewed-by: Christoph Hellwig <hch@lst.de> Acked-by: Christian Brauner <christian.brauner@ubuntu.com> Signed-off-by: Anthony Iliopoulos <ailiop@suse.com> Link: https://lore.kernel.org/r/20220119220248.32225-1-ailiop@suse.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | block: remove genhd.hChristoph Hellwig2022-02-021-1/+1
|/ | | | | | | | | | | | There is no good reason to keep genhd.h separate from the main blkdev.h header that includes it. So fold the contents of genhd.h into blkdev.h and remove genhd.h entirely. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Link: https://lore.kernel.org/r/20220124093913.742411-4-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
* devtmpfs regression fix: reconfigure on each mountNeilBrown2022-01-171-0/+7
| | | | | | | | | | | | | | | | | | Prior to Linux v5.4 devtmpfs used mount_single() which treats the given mount options as "remount" options, so it updates the configuration of the single super_block on each mount. Since that was changed, the mount options used for devtmpfs are ignored. This is a regression which affect systemd - which mounts devtmpfs with "-o mode=755,size=4m,nr_inodes=1m". This patch restores the "remount" effect by calling reconfigure_single() Fixes: d401727ea0d7 ("devtmpfs: don't mix {ramfs,shmem}_fill_super() with mount_single()") Acked-by: Christian Brauner <christian.brauner@ubuntu.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: NeilBrown <neilb@suse.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* devtmpfs: mount with noexec and nosuidKees Cook2021-12-301-2/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | devtmpfs is writable. Add the noexec and nosuid as default mount flags to prevent code execution from /dev. The systems who don't use systemd and who rely on CONFIG_DEVTMPFS_MOUNT=y are the ones to be protected by this patch. Other systems are fine with the udev solution. No sane program should be relying on executing from /dev. So this patch reduces the attack surface. It doesn't prevent any specific attack, but it reduces the possibility that someone can use /dev as a place to put executable code. Chrome OS has been carrying this patch for several years. It seems trivial and simple solution to improve the protection of /dev when CONFIG_DEVTMPFS_MOUNT=y. Original patch: https://lore.kernel.org/lkml/20121120215059.GA1859@www.outflux.net/ Cc: ellyjones@chromium.org Cc: Kay Sievers <kay@vrfy.org> Cc: Roland Eggner <edvx1@systemanalysen.net> Co-developed-by: Muhammad Usama Anjum <usama.anjum@collabora.com> Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Muhammad Usama Anjum <usama.anjum@collabora.com> Link: https://lore.kernel.org/r/YcMfDOyrg647RCmd@debian-BULLSEYE-live-builder-AMD64 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* devtmpfs: actually reclaim some init memoryRasmus Villemoes2021-03-231-2/+2
| | | | | | | | | | | | | | | | | | | | Currently gcc seems to inline devtmpfs_setup() into devtmpfsd(), so its memory footprint isn't reclaimed as intended. Mark it noinline to make sure it gets put in .init.text. While here, setup_done can also be put in .init.data: After complete() releases the internal spinlock, the completion object is never touched again by that thread, and the waiting thread doesn't proceed until it observes ->done while holding that spinlock. This is now the same pattern as for kthreadd_done in init/main.c: complete() is done in a __ref function, while the corresponding wait_for_completion() is in an __init function. Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Link: https://lore.kernel.org/r/20210312103027.2701413-2-linux@rasmusvillemoes.dk Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* devtmpfs: fix placement of complete() callRasmus Villemoes2021-03-231-1/+1
| | | | | | | | | | | | | | | | | | | | Calling complete() from within the __init function is wrong - theoretically, the init process could proceed all the way to freeing the init mem before the devtmpfsd thread gets to execute the return instruction in devtmpfs_setup(). In practice, it seems to be harmless as gcc inlines devtmpfs_setup() into devtmpfsd(). So the calls of the __init functions init_chdir() etc. actually happen from devtmpfs_setup(), but the __ref on that one silences modpost (it's all right, because those calls happen before the complete()). But it does make the __init annotation of the setup function moot, which we'll fix in a subsequent patch. Fixes: bcbacc4909f1 ("devtmpfs: refactor devtmpfsd()") Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Link: https://lore.kernel.org/r/20210312103027.2701413-1-linux@rasmusvillemoes.dk Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* namei: prepare for idmapped mountsChristian Brauner2021-01-241-4/+7
| | | | | | | | | | | | | | | | | | | The various vfs_*() helpers are called by filesystems or by the vfs itself to perform core operations such as create, link, mkdir, mknod, rename, rmdir, tmpfile and unlink. Enable them to handle idmapped mounts. If the inode is accessed through an idmapped mount map it into the mount's user namespace and pass it down. Afterwards the checks and operations are identical to non-idmapped mounts. If the initial user namespace is passed nothing changes so non-idmapped mounts will see identical behavior as before. Link: https://lore.kernel.org/r/20210121131959.646623-15-christian.brauner@ubuntu.com Cc: Christoph Hellwig <hch@lst.de> Cc: David Howells <dhowells@redhat.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: linux-fsdevel@vger.kernel.org Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
* attr: handle idmapped mountsChristian Brauner2021-01-241-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | When file attributes are changed most filesystems rely on the setattr_prepare(), setattr_copy(), and notify_change() helpers for initialization and permission checking. Let them handle idmapped mounts. If the inode is accessed through an idmapped mount map it into the mount's user namespace. Afterwards the checks are identical to non-idmapped mounts. If the initial user namespace is passed nothing changes so non-idmapped mounts will see identical behavior as before. Helpers that perform checks on the ia_uid and ia_gid fields in struct iattr assume that ia_uid and ia_gid are intended values and have already been mapped correctly at the userspace-kernelspace boundary as we already do today. If the initial user namespace is passed nothing changes so non-idmapped mounts will see identical behavior as before. Link: https://lore.kernel.org/r/20210121131959.646623-8-christian.brauner@ubuntu.com Cc: Christoph Hellwig <hch@lst.de> Cc: David Howells <dhowells@redhat.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: linux-fsdevel@vger.kernel.org Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
* init: add an init_chroot helperChristoph Hellwig2020-07-311-1/+1
| | | | | | | Add a simple helper to chroot with a kernel space file name and switch the early init code over to it. Remove the now unused ksys_chroot. Signed-off-by: Christoph Hellwig <hch@lst.de>
* init: add an init_chdir helperChristoph Hellwig2020-07-311-1/+1
| | | | | | | Add a simple helper to chdir with a kernel space file name and switch the early init code over to it. Remove the now unused ksys_chdir. Signed-off-by: Christoph Hellwig <hch@lst.de>
* init: add an init_mount helperChristoph Hellwig2020-07-311-2/+3
| | | | | | | | | Like do_mount, but takes a kernel pointer for the destination path. Switch over the mounts in the init code and devtmpfs to it, which just happen to work due to the implicit set_fs(KERNEL_DS) during early init right now. Signed-off-by: Christoph Hellwig <hch@lst.de>
* devtmpfs: refactor devtmpfsd()Christoph Hellwig2020-07-311-21/+31
| | | | | | | | | Split the main worker loop into a separate function. This allows devtmpfsd_setup to be marked __init, which will allows us to call __init routines for the setup work. devtmpfѕ itself needs a __ref marker for that to work, and a comment explaining why it works. Signed-off-by: Christoph Hellwig <hch@lst.de>
* Merge branch 'merge.nfs-fs_parse.1' of ↵Linus Torvalds2020-02-081-2/+2
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs file system parameter updates from Al Viro: "Saner fs_parser.c guts and data structures. The system-wide registry of syntax types (string/enum/int32/oct32/.../etc.) is gone and so is the horror switch() in fs_parse() that would have to grow another case every time something got added to that system-wide registry. New syntax types can be added by filesystems easily now, and their namespace is that of functions - not of system-wide enum members. IOW, they can be shared or kept private and if some turn out to be widely useful, we can make them common library helpers, etc., without having to do anything whatsoever to fs_parse() itself. And we already get that kind of requests - the thing that finally pushed me into doing that was "oh, and let's add one for timeouts - things like 15s or 2h". If some filesystem really wants that, let them do it. Without somebody having to play gatekeeper for the variants blessed by direct support in fs_parse(), TYVM. Quite a bit of boilerplate is gone. And IMO the data structures make a lot more sense now. -200LoC, while we are at it" * 'merge.nfs-fs_parse.1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (25 commits) tmpfs: switch to use of invalfc() cgroup1: switch to use of errorfc() et.al. procfs: switch to use of invalfc() hugetlbfs: switch to use of invalfc() cramfs: switch to use of errofc() et.al. gfs2: switch to use of errorfc() et.al. fuse: switch to use errorfc() et.al. ceph: use errorfc() and friends instead of spelling the prefix out prefix-handling analogues of errorf() and friends turn fs_param_is_... into functions fs_parse: handle optional arguments sanely fs_parse: fold fs_parameter_desc/fs_parameter_spec fs_parser: remove fs_parameter_description name field add prefix to fs_context->log ceph_parse_param(), ceph_parse_mon_ips(): switch to passing fc_log new primitive: __fs_parse() switch rbd and libceph to p_log-based primitives struct p_log, variants of warnf() et.al. taking that one instead teach logfc() to handle prefices, give it saner calling conventions get rid of cg_invalf() ...
| * fs_parse: fold fs_parameter_desc/fs_parameter_specAl Viro2020-02-071-2/+2
| | | | | | | | | | | | The former contains nothing but a pointer to an array of the latter... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | devtmpfs: factor out common tail of devtmpfs_{create,delete}_nodeRasmus Villemoes2020-01-221-25/+19
| | | | | | | | | | | | | | | | | | There's some common boilerplate in devtmpfs_{create,delete}_node, put that in a little helper. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Link: https://lore.kernel.org/r/20200115184154.3492-6-linux@rasmusvillemoes.dk Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | devtmpfs: initify a bitRasmus Villemoes2020-01-221-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | devtmpfs_mount() is only called from prepare_namespace() in init/do_mounts.c, which is an __init function, so devtmpfs_mount() can also be moved to .init.text. Then the mount_dev static variable is only referenced from __init functions (devtmpfs_mount and its initializer function mount_param). Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Link: https://lore.kernel.org/r/20200115184154.3492-5-linux@rasmusvillemoes.dk Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | devtmpfs: simplify initialization of mount_devRasmus Villemoes2020-01-221-5/+1
| | | | | | | | | | | | | | | | Avoid a bit of ifdeffery by using the IS_ENABLED() helper. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Link: https://lore.kernel.org/r/20200115184154.3492-4-linux@rasmusvillemoes.dk Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | devtmpfs: factor out setup part of devtmpfsd()Rasmus Villemoes2020-01-221-5/+12
| | | | | | | | | | | | | | | | | | | | Factor out the setup part of devtmpfsd() to make it a bit easier to see that we always call setup_done() exactly once (provided of course the kthread is succesfully created). Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Link: https://lore.kernel.org/r/20200115184154.3492-3-linux@rasmusvillemoes.dk Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | devtmpfs: fix theoretical stale pointer deref in devtmpfsd()Rasmus Villemoes2020-01-221-6/+8
|/ | | | | | | | | | | | | | | | After complete(&setup_done), devtmpfs_init proceeds and may actually return, invalidating the *err pointer, before devtmpfsd() proceeds to reading back *err. This is of course completely theoretical since the error conditions never trigger in practice, and even if they did, nobody cares about the exit value from a kernel thread, so it doesn't matter if we happen to read back some garbage from some other stack frame. Still, this isn't a pattern that should be copy-pasted, so fix it. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Link: https://lore.kernel.org/r/20200115184154.3492-2-linux@rasmusvillemoes.dk Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* devtmpfs: use do_mount() instead of ksys_mount()Dominik Brodowski2019-12-121-3/+3
| | | | | | | | | | | | In devtmpfs, do_mount() can be called directly instead of complex wrapping by ksys_mount(): - the first and third arguments are const strings in the kernel, and do not need to be copied over from userspace; - the fifth argument is NULL, and therefore no page needs to be copied over from userspace; - the second and fourth argument are passed through anyway. Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
* vfs: Convert ramfs, shmem, tmpfs, devtmpfs, rootfs to use the new mount APIDavid Howells2019-09-131-10/+6
| | | | | | | | | | | | | | | | | | | | | | | | | Convert the ramfs, shmem, tmpfs, devtmpfs and rootfs filesystems to the new internal mount API as the old one will be obsoleted and removed. This allows greater flexibility in communication of mount parameters between userspace, the VFS and the filesystem. See Documentation/filesystems/mount_api.txt for more information. Note that tmpfs is slightly tricky as it can contain embedded commas, so it can't be trivially split up using strsep() to break on commas in generic_parse_monolithic(). Instead, tmpfs has to supply its own generic parser. However, if tmpfs changes, then devtmpfs and rootfs, which are wrappers around tmpfs or ramfs, must change too - and thus so must ramfs, so these had to be converted also. [AV: rewritten] Signed-off-by: David Howells <dhowells@redhat.com> cc: Hugh Dickins <hughd@google.com> cc: linux-mm@kvack.org Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* make shmem_fill_super() staticAl Viro2019-09-051-1/+1
| | | | | | ... have callers use shmem_mount() Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* devtmpfs: don't mix {ramfs,shmem}_fill_super() with mount_single()Al Viro2019-09-051-6/+30
| | | | | | | | | | | | Create an internal-only type matching the current devtmpfs, never register it and have one kernel-internal mount done. That thing gets mounted only once, so it is free to use mount_nodev(). The "public" devtmpfs (the one we do register, and only after the internal mount of the real thing is done) simply gets and returns an extra reference to the internal superblock. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* constify ksys_mount() string argumentsAl Viro2019-07-051-2/+1
| | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* vfs: Suppress MS_* flag defs within the kernel unless explicitly enabledDavid Howells2018-12-201-0/+1
| | | | | | | | | | Only the mount namespace code that implements mount(2) should be using the MS_* flags. Suppress them inside the kernel unless uapi/linux/mount.h is included. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Reviewed-by: David Howells <dhowells@redhat.com>
* drivers/base/devtmpfs.c: don't pretend path is const in delete_pathRasmus Villemoes2018-09-161-1/+1
| | | | | | | | | path is the result of kstrdup, and we repeatedly call strrchr on it, modifying it through the returned pointer. So there's no reason to pretend path is const. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* kernel: add ksys_unshare() helper; remove in-kernel calls to sys_unshare()Dominik Brodowski2018-04-021-1/+1
| | | | | | | | | | | | | | | | Using this helper allows us to avoid the in-kernel calls to the sys_unshare() syscall. The ksys_ prefix denotes that this function is meant as a drop-in replacement for the syscall. In particular, it uses the same calling convention as sys_unshare(). This patch is part of a series which removes in-kernel calls to syscalls. On this basis, the syscall entry path can be streamlined. For details, see http://lkml.kernel.org/r/20180325162527.GA17492@light.dominikbrodowski.net Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Ingo Molnar <mingo@kernel.org> Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
* fs: add ksys_chdir() helper; remove in-kernel calls to sys_chdir()Dominik Brodowski2018-04-021-1/+1
| | | | | | | | | | | | | | | Using this helper allows us to avoid the in-kernel calls to the sys_chdir() syscall. The ksys_ prefix denotes that this function is meant as a drop-in replacement for the syscall. In particular, it uses the same calling convention as sys_chdir(). This patch is part of a series which removes in-kernel calls to syscalls. On this basis, the syscall entry path can be streamlined. For details, see http://lkml.kernel.org/r/20180325162527.GA17492@light.dominikbrodowski.net Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
* fs: add ksys_chroot() helper; remove-in kernel calls to sys_chroot()Dominik Brodowski2018-04-021-1/+1
| | | | | | | | | | | | | | | | | | Using this helper allows us to avoid the in-kernel calls to the sys_chroot() syscall. The ksys_ prefix denotes that this function is meant as a drop-in replacement for the syscall. In particular, it uses the same calling convention as sys_chroot(). In the near future, the fs-external callers of ksys_chroot() should be converted to use kern_path()/set_fs_root() directly. Then ksys_chroot() can be moved within sys_chroot() again. This patch is part of a series which removes in-kernel calls to syscalls. On this basis, the syscall entry path can be streamlined. For details, see http://lkml.kernel.org/r/20180325162527.GA17492@light.dominikbrodowski.net Cc: Alexander Viro <viro@zeniv.linux.org.uk> Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
* fs: add ksys_mount() helper; remove in-kernel calls to sys_mount()Dominik Brodowski2018-04-021-2/+3
| | | | | | | | | | | | | | | | | Using this helper allows us to avoid the in-kernel calls to the sys_mount() syscall. The ksys_ prefix denotes that this function is meant as a drop-in replacement for the syscall. In particular, it uses the same calling convention as sys_mount(). In the near future, all callers of ksys_mount() should be converted to call do_mount() directly. This patch is part of a series which removes in-kernel calls to syscalls. On this basis, the syscall entry path can be streamlined. For details, see http://lkml.kernel.org/r/20180325162527.GA17492@light.dominikbrodowski.net Cc: Alexander Viro <viro@zeniv.linux.org.uk> Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
* License cleanup: add SPDX GPL-2.0 license identifier to files with no licenseGreg Kroah-Hartman2017-11-021-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* statx: Add a system call to make enhanced file info availableDavid Howells2017-03-031-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add a system call to make extended file information available, including file creation and some attribute flags where available through the underlying filesystem. The getattr inode operation is altered to take two additional arguments: a u32 request_mask and an unsigned int flags that indicate the synchronisation mode. This change is propagated to the vfs_getattr*() function. Functions like vfs_stat() are now inline wrappers around new functions vfs_statx() and vfs_statx_fd() to reduce stack usage. ======== OVERVIEW ======== The idea was initially proposed as a set of xattrs that could be retrieved with getxattr(), but the general preference proved to be for a new syscall with an extended stat structure. A number of requests were gathered for features to be included. The following have been included: (1) Make the fields a consistent size on all arches and make them large. (2) Spare space, request flags and information flags are provided for future expansion. (3) Better support for the y2038 problem [Arnd Bergmann] (tv_sec is an __s64). (4) Creation time: The SMB protocol carries the creation time, which could be exported by Samba, which will in turn help CIFS make use of FS-Cache as that can be used for coherency data (stx_btime). This is also specified in NFSv4 as a recommended attribute and could be exported by NFSD [Steve French]. (5) Lightweight stat: Ask for just those details of interest, and allow a netfs (such as NFS) to approximate anything not of interest, possibly without going to the server [Trond Myklebust, Ulrich Drepper, Andreas Dilger] (AT_STATX_DONT_SYNC). (6) Heavyweight stat: Force a netfs to go to the server, even if it thinks its cached attributes are up to date [Trond Myklebust] (AT_STATX_FORCE_SYNC). And the following have been left out for future extension: (7) Data version number: Could be used by userspace NFS servers [Aneesh Kumar]. Can also be used to modify fill_post_wcc() in NFSD which retrieves i_version directly, but has just called vfs_getattr(). It could get it from the kstat struct if it used vfs_xgetattr() instead. (There's disagreement on the exact semantics of a single field, since not all filesystems do this the same way). (8) BSD stat compatibility: Including more fields from the BSD stat such as creation time (st_btime) and inode generation number (st_gen) [Jeremy Allison, Bernd Schubert]. (9) Inode generation number: Useful for FUSE and userspace NFS servers [Bernd Schubert]. (This was asked for but later deemed unnecessary with the open-by-handle capability available and caused disagreement as to whether it's a security hole or not). (10) Extra coherency data may be useful in making backups [Andreas Dilger]. (No particular data were offered, but things like last backup timestamp, the data version number and the DOS archive bit would come into this category). (11) Allow the filesystem to indicate what it can/cannot provide: A filesystem can now say it doesn't support a standard stat feature if that isn't available, so if, for instance, inode numbers or UIDs don't exist or are fabricated locally... (This requires a separate system call - I have an fsinfo() call idea for this). (12) Store a 16-byte volume ID in the superblock that can be returned in struct xstat [Steve French]. (Deferred to fsinfo). (13) Include granularity fields in the time data to indicate the granularity of each of the times (NFSv4 time_delta) [Steve French]. (Deferred to fsinfo). (14) FS_IOC_GETFLAGS value. These could be translated to BSD's st_flags. Note that the Linux IOC flags are a mess and filesystems such as Ext4 define flags that aren't in linux/fs.h, so translation in the kernel may be a necessity (or, possibly, we provide the filesystem type too). (Some attributes are made available in stx_attributes, but the general feeling was that the IOC flags were to ext[234]-specific and shouldn't be exposed through statx this way). (15) Mask of features available on file (eg: ACLs, seclabel) [Brad Boyer, Michael Kerrisk]. (Deferred, probably to fsinfo. Finding out if there's an ACL or seclabal might require extra filesystem operations). (16) Femtosecond-resolution timestamps [Dave Chinner]. (A __reserved field has been left in the statx_timestamp struct for this - if there proves to be a need). (17) A set multiple attributes syscall to go with this. =============== NEW SYSTEM CALL =============== The new system call is: int ret = statx(int dfd, const char *filename, unsigned int flags, unsigned int mask, struct statx *buffer); The dfd, filename and flags parameters indicate the file to query, in a similar way to fstatat(). There is no equivalent of lstat() as that can be emulated with statx() by passing AT_SYMLINK_NOFOLLOW in flags. There is also no equivalent of fstat() as that can be emulated by passing a NULL filename to statx() with the fd of interest in dfd. Whether or not statx() synchronises the attributes with the backing store can be controlled by OR'ing a value into the flags argument (this typically only affects network filesystems): (1) AT_STATX_SYNC_AS_STAT tells statx() to behave as stat() does in this respect. (2) AT_STATX_FORCE_SYNC will require a network filesystem to synchronise its attributes with the server - which might require data writeback to occur to get the timestamps correct. (3) AT_STATX_DONT_SYNC will suppress synchronisation with the server in a network filesystem. The resulting values should be considered approximate. mask is a bitmask indicating the fields in struct statx that are of interest to the caller. The user should set this to STATX_BASIC_STATS to get the basic set returned by stat(). It should be noted that asking for more information may entail extra I/O operations. buffer points to the destination for the data. This must be 256 bytes in size. ====================== MAIN ATTRIBUTES RECORD ====================== The following structures are defined in which to return the main attribute set: struct statx_timestamp { __s64 tv_sec; __s32 tv_nsec; __s32 __reserved; }; struct statx { __u32 stx_mask; __u32 stx_blksize; __u64 stx_attributes; __u32 stx_nlink; __u32 stx_uid; __u32 stx_gid; __u16 stx_mode; __u16 __spare0[1]; __u64 stx_ino; __u64 stx_size; __u64 stx_blocks; __u64 __spare1[1]; struct statx_timestamp stx_atime; struct statx_timestamp stx_btime; struct statx_timestamp stx_ctime; struct statx_timestamp stx_mtime; __u32 stx_rdev_major; __u32 stx_rdev_minor; __u32 stx_dev_major; __u32 stx_dev_minor; __u64 __spare2[14]; }; The defined bits in request_mask and stx_mask are: STATX_TYPE Want/got stx_mode & S_IFMT STATX_MODE Want/got stx_mode & ~S_IFMT STATX_NLINK Want/got stx_nlink STATX_UID Want/got stx_uid STATX_GID Want/got stx_gid STATX_ATIME Want/got stx_atime{,_ns} STATX_MTIME Want/got stx_mtime{,_ns} STATX_CTIME Want/got stx_ctime{,_ns} STATX_INO Want/got stx_ino STATX_SIZE Want/got stx_size STATX_BLOCKS Want/got stx_blocks STATX_BASIC_STATS [The stuff in the normal stat struct] STATX_BTIME Want/got stx_btime{,_ns} STATX_ALL [All currently available stuff] stx_btime is the file creation time, stx_mask is a bitmask indicating the data provided and __spares*[] are where as-yet undefined fields can be placed. Time fields are structures with separate seconds and nanoseconds fields plus a reserved field in case we want to add even finer resolution. Note that times will be negative if before 1970; in such a case, the nanosecond fields will also be negative if not zero. The bits defined in the stx_attributes field convey information about a file, how it is accessed, where it is and what it does. The following attributes map to FS_*_FL flags and are the same numerical value: STATX_ATTR_COMPRESSED File is compressed by the fs STATX_ATTR_IMMUTABLE File is marked immutable STATX_ATTR_APPEND File is append-only STATX_ATTR_NODUMP File is not to be dumped STATX_ATTR_ENCRYPTED File requires key to decrypt in fs Within the kernel, the supported flags are listed by: KSTAT_ATTR_FS_IOC_FLAGS [Are any other IOC flags of sufficient general interest to be exposed through this interface?] New flags include: STATX_ATTR_AUTOMOUNT Object is an automount trigger These are for the use of GUI tools that might want to mark files specially, depending on what they are. Fields in struct statx come in a number of classes: (0) stx_dev_*, stx_blksize. These are local system information and are always available. (1) stx_mode, stx_nlinks, stx_uid, stx_gid, stx_[amc]time, stx_ino, stx_size, stx_blocks. These will be returned whether the caller asks for them or not. The corresponding bits in stx_mask will be set to indicate whether they actually have valid values. If the caller didn't ask for them, then they may be approximated. For example, NFS won't waste any time updating them from the server, unless as a byproduct of updating something requested. If the values don't actually exist for the underlying object (such as UID or GID on a DOS file), then the bit won't be set in the stx_mask, even if the caller asked for the value. In such a case, the returned value will be a fabrication. Note that there are instances where the type might not be valid, for instance Windows reparse points. (2) stx_rdev_*. This will be set only if stx_mode indicates we're looking at a blockdev or a chardev, otherwise will be 0. (3) stx_btime. Similar to (1), except this will be set to 0 if it doesn't exist. ======= TESTING ======= The following test program can be used to test the statx system call: samples/statx/test-statx.c Just compile and run, passing it paths to the files you want to examine. The file is built automatically if CONFIG_SAMPLES is enabled. Here's some example output. Firstly, an NFS directory that crosses to another FSID. Note that the AUTOMOUNT attribute is set because transiting this directory will cause d_automount to be invoked by the VFS. [root@andromeda ~]# /tmp/test-statx -A /warthog/data statx(/warthog/data) = 0 results=7ff Size: 4096 Blocks: 8 IO Block: 1048576 directory Device: 00:26 Inode: 1703937 Links: 125 Access: (3777/drwxrwxrwx) Uid: 0 Gid: 4041 Access: 2016-11-24 09:02:12.219699527+0000 Modify: 2016-11-17 10:44:36.225653653+0000 Change: 2016-11-17 10:44:36.225653653+0000 Attributes: 0000000000001000 (-------- -------- -------- -------- -------- -------- ---m---- --------) Secondly, the result of automounting on that directory. [root@andromeda ~]# /tmp/test-statx /warthog/data statx(/warthog/data) = 0 results=7ff Size: 4096 Blocks: 8 IO Block: 1048576 directory Device: 00:27 Inode: 2 Links: 125 Access: (3777/drwxrwxrwx) Uid: 0 Gid: 4041 Access: 2016-11-24 09:02:12.219699527+0000 Modify: 2016-11-17 10:44:36.225653653+0000 Change: 2016-11-17 10:44:36.225653653+0000 Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* wrappers for ->i_mutex accessAl Viro2016-01-231-6/+6
| | | | | | | | | | | parallel to mutex_{lock,unlock,trylock,is_locked,lock_nested}, inode_foo(inode) being mutex_foo(&inode->i_mutex). Please, use those for access to ->i_mutex; over the coming cycle ->i_mutex will become rwsem, with ->lookup() done with it held only shared. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* VFS: assorted weird filesystems: d_inode() annotationsDavid Howells2015-04-151-16/+16
| | | | | Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* devtmpfs: Calling delete_path() only when necessaryAxel Lin2013-12-191-1/+1
| | | | | | | | | The deleted variable is always 1 in current code. Initialize deleted variable to be 0, so delete_path() will be called only when necessary. Signed-off-by: Axel Lin <axel.lin@ingics.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* locks: break delegations on any attribute modificationJ. Bruce Fields2013-11-091-2/+2
| | | | | | | | | | | | | NFSv4 uses leases to guarantee that clients can cache metadata as well as data. Cc: Mikulas Patocka <mikulas@artax.karlin.mff.cuni.cz> Cc: David Howells <dhowells@redhat.com> Cc: Tyler Hicks <tyhicks@canonical.com> Cc: Dustin Kirkland <dustin.kirkland@gazzang.com> Acked-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* locks: break delegations on unlinkJ. Bruce Fields2013-11-091-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We need to break delegations on any operation that changes the set of links pointing to an inode. Start with unlink. Such operations also hold the i_mutex on a parent directory. Breaking a delegation may require waiting for a timeout (by default 90 seconds) in the case of a unresponsive NFS client. To avoid blocking all directory operations, we therefore drop locks before waiting for the delegation. The logic then looks like: acquire locks ... test for delegation; if found: take reference on inode release locks wait for delegation break drop reference on inode retry It is possible this could never terminate. (Even if we take precautions to prevent another delegation being acquired on the same inode, we could get a different inode on each retry.) But this seems very unlikely. The initial test for a delegation happens after the lock on the target inode is acquired, but the directory inode may have been acquired further up the call stack. We therefore add a "struct inode **" argument to any intervening functions, which we use to pass the inode back up to the caller in the case it needs a delegation synchronously broken. Cc: David Howells <dhowells@redhat.com> Cc: Tyler Hicks <tyhicks@canonical.com> Cc: Dustin Kirkland <dustin.kirkland@gazzang.com> Acked-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* driver core: handle user namespaces properly with the uid/gid devtmpfs changeGreg Kroah-Hartman2013-04-111-9/+9
| | | | | | | | | | | | | Now that devtmpfs is caring about uid/gid, we need to use the correct internal types so users who have USER_NS enabled will have things work properly for them. Thanks to Eric for pointing this out, and the patch review. Reported-by: Eric W. Biederman <ebiederm@xmission.com> Cc: Kay Sievers <kay@vrfy.org> Cc: Ming Lei <ming.lei@canonical.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* driver core: devtmpfs: fix compile failure with CONFIG_UIDGID_STRICT_TYPE_CHECKSMing Lei2013-04-101-2/+2
| | | | | | | | | | | | | | | | If CONFIG_UIDGID_STRICT_TYPE_CHECKS is enalbed, the below compile failure will be triggered: drivers/base/devtmpfs.c: In function 'handle_create': drivers/base/devtmpfs.c:214:19: error: incompatible types when assigning to type 'kuid_t' from type 'uid_t' drivers/base/devtmpfs.c:215:19: error: incompatible types when assigning to type 'kgid_t' from type 'gid_t' make[2]: *** [drivers/base/devtmpfs.o] Error 1 This patch fixes the compile failure. Signed-off-by: Ming Lei <ming.lei@canonical.com> Cc: Kay Sievers <kay@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* devtmpfs: add base.h includeGreg Kroah-Hartman2013-04-101-0/+1
| | | | | | | This fixes a sparse warning, and is a good idea given that the devtmpfs_init() prototype is in this file. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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