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2024-02-06fs: remove the inode argument to ->d_real() methodAmir Goldstein1-9/+7
The only remaining user of ->d_real() method is d_real_inode(), which passed NULL inode argument to get the real data dentry. There are no longer any users that call ->d_real() with a non-NULL inode argument for getting a detry from a specific underlying layer. Remove the inode argument of the method and replace it with an integer 'type' argument, to allow callers to request the real metadata dentry instead of the real data dentry. All the current users of d_real_inode() (e.g. uprobe) continue to get the real data inode. Caller that need to get the real metadata inode (e.g. IMA/EVM) can use d_inode(d_real(dentry, D_REAL_METADATA)). Signed-off-by: Amir Goldstein <amir73il@gmail.com> Link: https://lore.kernel.org/r/20240202110132.1584111-3-amir73il@gmail.com Tested-by: Stefan Berger <stefanb@linux.ibm.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-01-12Merge tag 'docs-6.8' of git://git.lwn.net/linuxLinus Torvalds1-1/+1
Pull documentation update from Jonathan Corbet: "Another moderately busy cycle for documentation, including: - The minimum Sphinx requirement has been raised to 2.4.4, following a warning that was added in 6.2 - Some reworking of the Documentation/process front page to, hopefully, make it more useful - Various kernel-doc tweaks to, for example, make it deal properly with __counted_by annotations - We have also restored a warning for documentation of nonexistent structure members that disappeared a while back. That had the delightful consequence of adding some 600 warnings to the docs build. A sustained effort by Randy, Vegard, and myself has addressed almost all of those, bringing the documentation back into sync with the code. The fixes are going through the appropriate maintainer trees - Various improvements to the HTML rendered docs, including automatic links to Git revisions and a nice new pulldown to make translations easy to access - Speaking of translations, more of those for Spanish and Chinese ... plus the usual stream of documentation updates and typo fixes" * tag 'docs-6.8' of git://git.lwn.net/linux: (57 commits) MAINTAINERS: use tabs for indent of CONFIDENTIAL COMPUTING THREAT MODEL A reworked process/index.rst ring-buffer/Documentation: Add documentation on buffer_percent file Translated the RISC-V architecture boot documentation. Docs: remove mentions of fdformat from util-linux Docs/zh_CN: Fix the meaning of DEBUG to pr_debug() Documentation: move driver-api/dcdbas to userspace-api/ Documentation: move driver-api/isapnp to userspace-api/ Documentation/core-api : fix typo in workqueue Documentation/trace: Fixed typos in the ftrace FLAGS section kernel-doc: handle a void function without producing a warning scripts/get_abi.pl: ignore some temp files docs: kernel_abi.py: fix command injection scripts/get_abi: fix source path leak CREDITS, MAINTAINERS, docs/process/howto: Update man-pages' maintainer docs: translations: add translations links when they exist kernel-doc: Align quick help and the code MAINTAINERS: add reviewer for Spanish translations docs: ignore __counted_by attribute in structure definitions scripts: kernel-doc: Clarify missing struct member description ..
2023-12-11fs: convert error_remove_page to error_remove_folioMatthew Wilcox (Oracle)1-3/+3
There were already assertions that we were not passing a tail page to error_remove_page(), so make the compiler enforce that by converting everything to pass and use a folio. Link: https://lkml.kernel.org/r/20231117161447.2461643-7-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Naoya Horiguchi <naoya.horiguchi@nec.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-11-17docs: vfs: fix typo in struct xattr_handlersAriel Miculas1-1/+1
The structure is called struct xattr_handler, singular, not plural. Fixing the typo also makes it greppable with the whole word matching flag. Signed-off-by: Ariel Miculas <amiculas@cisco.com> Acked-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Message-ID: <20231027152101.226296-1-amiculas@cisco.com>
2023-08-31Merge tag 'docs-6.6' of git://git.lwn.net/linuxLinus Torvalds1-7/+2
Pull documentation updates from Jonathan Corbet: "Documentation work keeps chugging along; this includes: - Work from Carlos Bilbao to integrate rustdoc output into the generated HTML documentation. This took some work to figure out how to do it without slowing the docs build and without creating people who don't have Rust installed, but Carlos got there - Move the loongarch and mips architecture documentation under Documentation/arch/ - Some more maintainer documentation from Jakub ... plus the usual assortment of updates, translations, and fixes" * tag 'docs-6.6' of git://git.lwn.net/linux: (56 commits) Docu: genericirq.rst: fix irq-example input: docs: pxrc: remove reference to phoenix-sim Documentation: serial-console: Fix literal block marker docs/mm: remove references to hmm_mirror ops and clean typos docs/zh_CN: correct regi_chg(),regi_add() to region_chg(),region_add() Documentation: Fix typos Documentation/ABI: Fix typos scripts: kernel-doc: fix macro handling in enums scripts: kernel-doc: parse DEFINE_DMA_UNMAP_[ADDR|LEN] Documentation: riscv: Update boot image header since EFI stub is supported Documentation: riscv: Add early boot document Documentation: arm: Add bootargs to the table of added DT parameters docs: kernel-parameters: Refer to the correct bitmap function doc: update params of memhp_default_state= docs: Add book to process/kernel-docs.rst docs: sparse: fix invalid link addresses docs: vfs: clean up after the iterate() removal docs: Add a section on surveys to the researcher guidelines docs: move mips under arch docs: move loongarch under arch ...
2023-08-28Merge tag 'v6.6-vfs.super' of ↵Linus Torvalds1-2/+4
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull superblock updates from Christian Brauner: "This contains the super rework that was ready for this cycle. The first part changes the order of how we open block devices and allocate superblocks, contains various cleanups, simplifications, and a new mechanism to wait on superblock state changes. This unblocks work to ultimately limit the number of writers to a block device. Jan has already scheduled follow-up work that will be ready for v6.7 and allows us to restrict the number of writers to a given block device. That series builds on this work right here. The second part contains filesystem freezing updates. Overview: The generic superblock changes are rougly organized as follows (ignoring additional minor cleanups): (1) Removal of the bd_super member from struct block_device. This was a very odd back pointer to struct super_block with unclear rules. For all relevant places we have other means to get the same information so just get rid of this. (2) Simplify rules for superblock cleanup. Roughly, everything that is allocated during fs_context initialization and that's stored in fs_context->s_fs_info needs to be cleaned up by the fs_context->free() implementation before the superblock allocation function has been called successfully. After sget_fc() returned fs_context->s_fs_info has been transferred to sb->s_fs_info at which point sb->kill_sb() if fully responsible for cleanup. Adhering to these rules means that cleanup of sb->s_fs_info in fill_super() is to be avoided as it's brittle and inconsistent. Cleanup shouldn't be duplicated between sb->put_super() as sb->put_super() is only called if sb->s_root has been set aka when the filesystem has been successfully born (SB_BORN). That complexity should be avoided. This also means that block devices are to be closed in sb->kill_sb() instead of sb->put_super(). More details in the lower section. (3) Make it possible to lookup or create a superblock before opening block devices There's a subtle dependency on (2) as some filesystems did rely on fill_super() to be called in order to correctly clean up sb->s_fs_info. All these filesystems have been fixed. (4) Switch most filesystem to follow the same logic as the generic mount code now does as outlined in (3). (5) Use the superblock as the holder of the block device. We can now easily go back from block device to owning superblock. (6) Export and extend the generic fs_holder_ops and use them as holder ops everywhere and remove the filesystem specific holder ops. (7) Call from the block layer up into the filesystem layer when the block device is removed, allowing to shut down the filesystem without risk of deadlocks. (8) Get rid of get_super(). We can now easily go back from the block device to owning superblock and can call up from the block layer into the filesystem layer when the device is removed. So no need to wade through all registered superblock to find the owning superblock anymore" Link: https://lore.kernel.org/lkml/20230824-prall-intakt-95dbffdee4a0@brauner/ * tag 'v6.6-vfs.super' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (47 commits) super: use higher-level helper for {freeze,thaw} super: wait until we passed kill super super: wait for nascent superblocks super: make locking naming consistent super: use locking helpers fs: simplify invalidate_inodes fs: remove get_super block: call into the file system for ioctl BLKFLSBUF block: call into the file system for bdev_mark_dead block: consolidate __invalidate_device and fsync_bdev block: drop the "busy inodes on changed media" log message dasd: also call __invalidate_device when setting the device offline amiflop: don't call fsync_bdev in FDFMTBEG floppy: call disk_force_media_change when changing the format block: simplify the disk_force_media_change interface nbd: call blk_mark_disk_dead in nbd_clear_sock_ioctl xfs use fs_holder_ops for the log and RT devices xfs: drop s_umount over opening the log and RT devices ext4: use fs_holder_ops for the log device ext4: drop s_umount over opening the log device ...
2023-08-18Documentation: Fix typosBjorn Helgaas1-1/+1
Fix typos in Documentation. Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Link: https://lore.kernel.org/r/20230814212822.193684-4-helgaas@kernel.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2023-08-18docs: vfs: clean up after the iterate() removalJonathan Corbet1-6/+1
Commit 3e3271549670 ("vfs: get rid of old '->iterate' directory operation") removed the iterate() file_operations member, but neglected to clean up the associated documentation. Get rid of the leftovers. Link: https://lore.kernel.org/r/874jl945bv.fsf@meer.lwn.net Reviewed-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2023-08-09libfs: Add directory operations for stable offsetsChuck Lever1-1/+5
Create a vector of directory operations in fs/libfs.c that handles directory seeks and readdir via stable offsets instead of the current cursor-based mechanism. For the moment these are unused. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Message-Id: <168814732984.530310.11190772066786107220.stgit@manet.1015granger.net> Signed-off-by: Christian Brauner <brauner@kernel.org>
2023-07-17fs: distinguish between user initiated freeze and kernel initiated freezeDarrick J. Wong1-2/+4
Userspace can freeze a filesystem using the FIFREEZE ioctl or by suspending the block device; this state persists until userspace thaws the filesystem with the FITHAW ioctl or resuming the block device. Since commit 18e9e5104fcd ("Introduce freeze_super and thaw_super for the fsfreeze ioctl") we only allow the first freeze command to succeed. The kernel may decide that it is necessary to freeze a filesystem for its own internal purposes, such as suspends in progress, filesystem fsck activities, or quiescing a device prior to removal. Userspace thaw commands must never break a kernel freeze, and kernel thaw commands shouldn't undo userspace's freeze command. Introduce a couple of freeze holder flags and wire it into the sb_writers state. One kernel and one userspace freeze are allowed to coexist at the same time; the filesystem will not thaw until both are lifted. I wonder if the f2fs/gfs2 code should be using a kernel freeze here, but for now we'll use FREEZE_HOLDER_USERSPACE to preserve existing behaviors. Cc: mcgrof@kernel.org Cc: jack@suse.cz Cc: hch@infradead.org Cc: ruansy.fnst@fujitsu.com Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Jan Kara <jack@suse.cz>
2023-06-25sock: Remove ->sendpage*() in favour of sendmsg(MSG_SPLICE_PAGES)David Howells1-1/+0
Remove ->sendpage() and ->sendpage_locked(). sendmsg() with MSG_SPLICE_PAGES should be used instead. This allows multiple pages and multipage folios to be passed through. Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Marc Kleine-Budde <mkl@pengutronix.de> # for net/can cc: Jens Axboe <axboe@kernel.dk> cc: Matthew Wilcox <willy@infradead.org> cc: linux-afs@lists.infradead.org cc: mptcp@lists.linux.dev cc: rds-devel@oss.oracle.com cc: tipc-discussion@lists.sourceforge.net cc: virtualization@lists.linux-foundation.org Link: https://lore.kernel.org/r/20230623225513.2732256-16-dhowells@redhat.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-03-14docs: filesystems: vfs: actualize struct super_operations descriptionAlexander Mikhalitsyn1-15/+59
Added/updated descriptions for super_operations: - free_inode method - evict_inode method - freeze_super/thaw_super method - show_{devname,path,stats} procfs-related methods - get_dquots method Cc: Eric Biggers <ebiggers@kernel.org> Cc: Miklos Szeredi <mszeredi@redhat.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Christian Brauner <brauner@kernel.org> Cc: linux-fsdevel@vger.kernel.org Cc: linux-doc@vger.kernel.org Signed-off-by: Alexander Mikhalitsyn <aleksandr.mikhalitsyn@canonical.com> Reviewed-by: Christian Brauner <brauner@kernel.org> Link: https://lore.kernel.org/r/20230313130718.253708-3-aleksandr.mikhalitsyn@canonical.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2023-03-14docs: filesystems: vfs: actualize struct file_system_type descriptionAlexander Mikhalitsyn1-4/+27
Added descriptions for: - fscontext API ('init_fs_context' method, 'parameters' field) - 'fs_supers' field Cc: Eric Biggers <ebiggers@kernel.org> Cc: Miklos Szeredi <mszeredi@redhat.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Christian Brauner <brauner@kernel.org> Cc: linux-fsdevel@vger.kernel.org Cc: linux-doc@vger.kernel.org Signed-off-by: Alexander Mikhalitsyn <aleksandr.mikhalitsyn@canonical.com> Reviewed-by: Christian Brauner <brauner@kernel.org> Link: https://lore.kernel.org/r/20230313130718.253708-2-aleksandr.mikhalitsyn@canonical.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2023-03-07docs: Correct missing "d_" prefix for dentry_operations member d_weak_revalidateGlenn Washburn1-1/+1
The details for struct dentry_operations member d_weak_revalidate is missing a "d_" prefix. Fixes: af96c1e304f7 ("docs: filesystems: vfs: Convert vfs.txt to RST") Signed-off-by: Glenn Washburn <development@efficientek.com> Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org> Link: https://lore.kernel.org/r/20230227184042.2375235-1-development@efficientek.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2023-01-19fs: port ->permission() to pass mnt_idmapChristian Brauner1-1/+1
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>
2023-01-19fs: port ->fileattr_set() to pass mnt_idmapChristian Brauner1-1/+1
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>
2023-01-19fs: port ->set_acl() to pass mnt_idmapChristian Brauner1-1/+1
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>
2023-01-19fs: port ->get_acl() to pass mnt_idmapChristian Brauner1-1/+1
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>
2023-01-19fs: port ->tmpfile() to pass mnt_idmapChristian Brauner1-1/+1
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>
2023-01-19fs: port ->rename() to pass mnt_idmapChristian Brauner1-1/+1
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>
2023-01-19fs: port ->mknod() to pass mnt_idmapChristian Brauner1-1/+1
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>
2023-01-19fs: port ->mkdir() to pass mnt_idmapChristian Brauner1-1/+1
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>
2023-01-19fs: port ->symlink() to pass mnt_idmapChristian Brauner1-1/+1
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>
2023-01-19fs: port ->create() to pass mnt_idmapChristian Brauner1-1/+1
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>
2023-01-19fs: port ->getattr() to pass mnt_idmapChristian Brauner1-1/+1
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>
2023-01-19fs: port ->setattr() to pass mnt_idmapChristian Brauner1-1/+1
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>
2022-10-20fs: add new get acl methodChristian Brauner1-0/+1
The current way of setting and getting posix acls through the generic xattr interface is error prone and type unsafe. The vfs needs to interpret and fixup posix acls before storing or reporting it to userspace. Various hacks exist to make this work. The code is hard to understand and difficult to maintain in it's current form. Instead of making this work by hacking posix acls through xattr handlers we are building a dedicated posix acl api around the get and set inode operations. This removes a lot of hackiness and makes the codepaths easier to maintain. A lot of background can be found in [1]. Since some filesystem rely on the dentry being available to them when setting posix acls (e.g., 9p and cifs) they cannot rely on the old get acl inode operation to retrieve posix acl and need to implement their own custom handlers because of that. In a previous patch we renamed the old get acl inode operation to ->get_inode_acl(). We decided to rename it and implement a new one since ->get_inode_acl() is called generic_permission() and inode_permission() both of which can be called during an filesystem's ->permission() handler. So simply passing a dentry argument to ->get_acl() would have amounted to also having to pass a dentry argument to ->permission(). We avoided that change. This adds a new ->get_acl() inode operations which takes a dentry argument which filesystems such as 9p, cifs, and overlayfs can implement to get posix acls. Link: https://lore.kernel.org/all/20220801145520.1532837-1-brauner@kernel.org [1] Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
2022-10-20fs: rename current get acl methodChristian Brauner1-1/+1
The current way of setting and getting posix acls through the generic xattr interface is error prone and type unsafe. The vfs needs to interpret and fixup posix acls before storing or reporting it to userspace. Various hacks exist to make this work. The code is hard to understand and difficult to maintain in it's current form. Instead of making this work by hacking posix acls through xattr handlers we are building a dedicated posix acl api around the get and set inode operations. This removes a lot of hackiness and makes the codepaths easier to maintain. A lot of background can be found in [1]. The current inode operation for getting posix acls takes an inode argument but various filesystems (e.g., 9p, cifs, overlayfs) need access to the dentry. In contrast to the ->set_acl() inode operation we cannot simply extend ->get_acl() to take a dentry argument. The ->get_acl() inode operation is called from: acl_permission_check() -> check_acl() -> get_acl() which is part of generic_permission() which in turn is part of inode_permission(). Both generic_permission() and inode_permission() are called in the ->permission() handler of various filesystems (e.g., overlayfs). So simply passing a dentry argument to ->get_acl() would amount to also having to pass a dentry argument to ->permission(). We should avoid this unnecessary change. So instead of extending the existing inode operation rename it from ->get_acl() to ->get_inode_acl() and add a ->get_acl() method later that passes a dentry argument and which filesystems that need access to the dentry can implement instead of ->get_inode_acl(). Filesystems like cifs which allow setting and getting posix acls but not using them for permission checking during lookup can simply not implement ->get_inode_acl(). This is intended to be a non-functional change. Link: https://lore.kernel.org/all/20220801145520.1532837-1-brauner@kernel.org [1] Suggested-by/Inspired-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
2022-10-19fs: pass dentry to set acl methodChristian Brauner1-1/+1
The current way of setting and getting posix acls through the generic xattr interface is error prone and type unsafe. The vfs needs to interpret and fixup posix acls before storing or reporting it to userspace. Various hacks exist to make this work. The code is hard to understand and difficult to maintain in it's current form. Instead of making this work by hacking posix acls through xattr handlers we are building a dedicated posix acl api around the get and set inode operations. This removes a lot of hackiness and makes the codepaths easier to maintain. A lot of background can be found in [1]. Since some filesystem rely on the dentry being available to them when setting posix acls (e.g., 9p and cifs) they cannot rely on set acl inode operation. But since ->set_acl() is required in order to use the generic posix acl xattr handlers filesystems that do not implement this inode operation cannot use the handler and need to implement their own dedicated posix acl handlers. Update the ->set_acl() inode method to take a dentry argument. This allows all filesystems to rely on ->set_acl(). As far as I can tell all codepaths can be switched to rely on the dentry instead of just the inode. Note that the original motivation for passing the dentry separate from the inode instead of just the dentry in the xattr handlers was because of security modules that call security_d_instantiate(). This hook is called during d_instantiate_new(), d_add(), __d_instantiate_anon(), and d_splice_alias() to initialize the inode's security context and possibly to set security.* xattrs. Since this only affects security.* xattrs this is completely irrelevant for posix acls. Link: https://lore.kernel.org/all/20220801145520.1532837-1-brauner@kernel.org [1] Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
2022-10-11Merge tag 'pull-tmpfile' of ↵Linus Torvalds1-2/+4
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs tmpfile updates from Al Viro: "Miklos' ->tmpfile() signature change; pass an unopened struct file to it, let it open the damn thing. Allows to add tmpfile support to FUSE" * tag 'pull-tmpfile' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: fuse: implement ->tmpfile() vfs: open inside ->tmpfile() vfs: move open right after ->tmpfile() vfs: make vfs_tmpfile() static ovl: use vfs_tmpfile_open() helper cachefiles: use vfs_tmpfile_open() helper cachefiles: only pass inode to *mark_inode_inuse() helpers cachefiles: tmpfile error handling cleanup hugetlbfs: cleanup mknod and tmpfile vfs: add vfs_tmpfile_open() helper
2022-09-30fs: record I_DIRTY_TIME even if inode already has I_DIRTY_INODELukas Czerner1-0/+3
Currently the I_DIRTY_TIME will never get set if the inode already has I_DIRTY_INODE with assumption that it supersedes I_DIRTY_TIME. That's true, however ext4 will only update the on-disk inode in ->dirty_inode(), not on actual writeback. As a result if the inode already has I_DIRTY_INODE state by the time we get to __mark_inode_dirty() only with I_DIRTY_TIME, the time was already filled into on-disk inode and will not get updated until the next I_DIRTY_INODE update, which might never come if we crash or get a power failure. The problem can be reproduced on ext4 by running xfstest generic/622 with -o iversion mount option. Fix it by allowing I_DIRTY_TIME to be set even if the inode already has I_DIRTY_INODE. Also make sure that the case is properly handled in writeback_single_inode() as well. Additionally changes in xfs_fs_dirty_inode() was made to accommodate for I_DIRTY_TIME in flag. Thanks Jan Kara for suggestions on how to make this work properly. Cc: Dave Chinner <david@fromorbit.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: stable@kernel.org Signed-off-by: Lukas Czerner <lczerner@redhat.com> Suggested-by: Jan Kara <jack@suse.cz> Reviewed-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20220825100657.44217-1-lczerner@redhat.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2022-09-24vfs: open inside ->tmpfile()Miklos Szeredi1-2/+4
This is in preparation for adding tmpfile support to fuse, which requires that the tmpfile creation and opening are done as a single operation. Replace the 'struct dentry *' argument of i_op->tmpfile with 'struct file *'. Call finish_open_simple() as the last thing in ->tmpfile() instances (may be omitted in the error case). Change d_tmpfile() argument to 'struct file *' as well to make callers more readable. Reviewed-by: Christian Brauner (Microsoft) <brauner@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2022-08-02fs: Add aops->migrate_folioMatthew Wilcox (Oracle)1-7/+7
Provide a folio-based replacement for aops->migratepage. Update the documentation to document migrate_folio instead of migratepage. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: Christoph Hellwig <hch@lst.de>
2022-08-02mm: Convert all PageMovable users to movable_operationsMatthew Wilcox (Oracle)1-12/+0
These drivers are rather uncomfortably hammered into the address_space_operations hole. They aren't filesystems and don't behave like filesystems. They just need their own movable_operations structure, which we can point to directly from page->mapping. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
2022-06-29docs: Improve ->read_folio documentationMatthew Wilcox (Oracle)1-7/+32
Add information on the use of 'file', whether ->read_folio should be synchronous, and steer new callers towards calling read_mapping_folio() instead of calling ->read_folio directly. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
2022-05-26Merge tag 'mm-stable-2022-05-25' of ↵Linus Torvalds1-5/+12
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: "Almost all of MM here. A few things are still getting finished off, reviewed, etc. - Yang Shi has improved the behaviour of khugepaged collapsing of readonly file-backed transparent hugepages. - Johannes Weiner has arranged for zswap memory use to be tracked and managed on a per-cgroup basis. - Munchun Song adds a /proc knob ("hugetlb_optimize_vmemmap") for runtime enablement of the recent huge page vmemmap optimization feature. - Baolin Wang contributes a series to fix some issues around hugetlb pagetable invalidation. - Zhenwei Pi has fixed some interactions between hwpoisoned pages and virtualization. - Tong Tiangen has enabled the use of the presently x86-only page_table_check debugging feature on arm64 and riscv. - David Vernet has done some fixup work on the memcg selftests. - Peter Xu has taught userfaultfd to handle write protection faults against shmem- and hugetlbfs-backed files. - More DAMON development from SeongJae Park - adding online tuning of the feature and support for monitoring of fixed virtual address ranges. Also easier discovery of which monitoring operations are available. - Nadav Amit has done some optimization of TLB flushing during mprotect(). - Neil Brown continues to labor away at improving our swap-over-NFS support. - David Hildenbrand has some fixes to anon page COWing versus get_user_pages(). - Peng Liu fixed some errors in the core hugetlb code. - Joao Martins has reduced the amount of memory consumed by device-dax's compound devmaps. - Some cleanups of the arch-specific pagemap code from Anshuman Khandual. - Muchun Song has found and fixed some errors in the TLB flushing of transparent hugepages. - Roman Gushchin has done more work on the memcg selftests. ... and, of course, many smaller fixes and cleanups. Notably, the customary million cleanup serieses from Miaohe Lin" * tag 'mm-stable-2022-05-25' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (381 commits) mm: kfence: use PAGE_ALIGNED helper selftests: vm: add the "settings" file with timeout variable selftests: vm: add "test_hmm.sh" to TEST_FILES selftests: vm: check numa_available() before operating "merge_across_nodes" in ksm_tests selftests: vm: add migration to the .gitignore selftests/vm/pkeys: fix typo in comment ksm: fix typo in comment selftests: vm: add process_mrelease tests Revert "mm/vmscan: never demote for memcg reclaim" mm/kfence: print disabling or re-enabling message include/trace/events/percpu.h: cleanup for "percpu: improve percpu_alloc_percpu event trace" include/trace/events/mmflags.h: cleanup for "tracing: incorrect gfp_t conversion" mm: fix a potential infinite loop in start_isolate_page_range() MAINTAINERS: add Muchun as co-maintainer for HugeTLB zram: fix Kconfig dependency warning mm/shmem: fix shmem folio swapoff hang cgroup: fix an error handling path in alloc_pagecache_max_30M() mm: damon: use HPAGE_PMD_SIZE tracing: incorrect isolate_mote_t cast in mm_vmscan_lru_isolate nodemask.h: fix compilation error with GCC12 ...
2022-05-10fs: Add free_folio address space operationMatthew Wilcox (Oracle)1-3/+3
Include documentation and convert the callers to use ->free_folio as well as ->freepage. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
2022-05-10fs: Add aops->release_folioMatthew Wilcox (Oracle)1-23/+22
This replaces aops->releasepage. Update the documentation, and call it if it exists. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: Jeff Layton <jlayton@kernel.org>
2022-05-10doc: update documentation for swap_activate and swap_rwNeilBrown1-5/+12
This documentation for ->swap_activate() has been out-of-date for a long time. This patch updates it to match recent changes, and adds documentation for the associated ->swap_rw() Link: https://lkml.kernel.org/r/164859778126.29473.6778751233552859461.stgit@noble.brown Signed-off-by: NeilBrown <neilb@suse.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Tested-by: David Howells <dhowells@redhat.com> Tested-by: Geert Uytterhoeven <geert+renesas@glider.be> Cc: Hugh Dickins <hughd@google.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Trond Myklebust <trond.myklebust@hammerspace.com> Cc: Miaohe Lin <linmiaohe@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-05-09fs: Add read_folio documentationMatthew Wilcox (Oracle)1-10/+10
Convert all the ->readpage documentation to ->read_folio. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
2022-05-08fs: Convert is_dirty_writeback() to take a folioMatthew Wilcox (Oracle)1-5/+5
Pass a folio instead of a page to aops->is_dirty_writeback(). Convert both implementations and the caller. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: Christoph Hellwig <hch@lst.de>
2022-05-08fs: Remove flags parameter from aops->write_beginMatthew Wilcox (Oracle)1-4/+1
There are no more aop flags left, so remove the parameter. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: Christoph Hellwig <hch@lst.de>
2022-04-01fs: Remove ->readpages address space operationMatthew Wilcox (Oracle)1-11/+0
All filesystems have now been converted to use ->readahead, so remove the ->readpages operation and fix all the comments that used to refer to it. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Al Viro <viro@zeniv.linux.org.uk> Acked-by: Al Viro <viro@zeniv.linux.org.uk>
2022-03-23Merge tag 'folio-5.18b' of git://git.infradead.org/users/willy/pagecacheLinus Torvalds1-23/+23
Pull filesystem folio updates from Matthew Wilcox: "Primarily this series converts some of the address_space operations to take a folio instead of a page. Notably: - a_ops->is_partially_uptodate() takes a folio instead of a page and changes the type of the 'from' and 'count' arguments to make it obvious they're bytes. - a_ops->invalidatepage() becomes ->invalidate_folio() and has a similar type change. - a_ops->launder_page() becomes ->launder_folio() - a_ops->set_page_dirty() becomes ->dirty_folio() and adds the address_space as an argument. There are a couple of other misc changes up front that weren't worth separating into their own pull request" * tag 'folio-5.18b' of git://git.infradead.org/users/willy/pagecache: (53 commits) fs: Remove aops ->set_page_dirty fb_defio: Use noop_dirty_folio() fs: Convert __set_page_dirty_no_writeback to noop_dirty_folio fs: Convert __set_page_dirty_buffers to block_dirty_folio nilfs: Convert nilfs_set_page_dirty() to nilfs_dirty_folio() mm: Convert swap_set_page_dirty() to swap_dirty_folio() ubifs: Convert ubifs_set_page_dirty to ubifs_dirty_folio f2fs: Convert f2fs_set_node_page_dirty to f2fs_dirty_node_folio f2fs: Convert f2fs_set_data_page_dirty to f2fs_dirty_data_folio f2fs: Convert f2fs_set_meta_page_dirty to f2fs_dirty_meta_folio afs: Convert afs_dir_set_page_dirty() to afs_dir_dirty_folio() btrfs: Convert extent_range_redirty_for_io() to use folios fs: Convert trivial uses of __set_page_dirty_nobuffers to filemap_dirty_folio btrfs: Convert from set_page_dirty to dirty_folio fscache: Convert fscache_set_page_dirty() to fscache_dirty_folio() fs: Add aops->dirty_folio fs: Remove aops->launder_page orangefs: Convert launder_page to launder_folio nfs: Convert from launder_page to launder_folio fuse: Convert from launder_page to launder_folio ...
2022-03-23mm: document and polish read-ahead codeNeilBrown1-6/+10
Add some "big-picture" documentation for read-ahead and polish the code to make it fit this documentation. The meaning of ->async_size is clarified to match its name. i.e. Any request to ->readahead() has a sync part and an async part. The caller will wait for the sync pages to complete, but will not wait for the async pages. The first async page is still marked PG_readahead Note that the current function names page_cache_sync_ra() and page_cache_async_ra() are misleading. All ra request are partly sync and partly async, so either part can be empty. A page_cache_sync_ra() request will usually set ->async_size non-zero, implying it is not all synchronous. When a non-zero req_count is passed to page_cache_async_ra(), the implication is that some prefix of the request is synchronous, though the calculation made there is incorrect - I haven't tried to fix it. Link: https://lkml.kernel.org/r/164549983734.9187.11586890887006601405.stgit@noble.brown Signed-off-by: NeilBrown <neilb@suse.de> Cc: Anna Schumaker <Anna.Schumaker@Netapp.com> Cc: Chao Yu <chao@kernel.org> Cc: Darrick J. Wong <djwong@kernel.org> Cc: Ilya Dryomov <idryomov@gmail.com> Cc: Jaegeuk Kim <jaegeuk@kernel.org> Cc: Jan Kara <jack@suse.cz> Cc: Jeff Layton <jlayton@kernel.org> Cc: Jens Axboe <axboe@kernel.dk> Cc: Lars Ellenberg <lars.ellenberg@linbit.com> Cc: Miklos Szeredi <miklos@szeredi.hu> Cc: Paolo Valente <paolo.valente@linaro.org> Cc: Philipp Reisner <philipp.reisner@linbit.com> Cc: Ryusuke Konishi <konishi.ryusuke@gmail.com> Cc: Trond Myklebust <trond.myklebust@hammerspace.com> Cc: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-15fs: Add aops->dirty_folioMatthew Wilcox (Oracle)1-8/+8
This replaces ->set_page_dirty(). It returns a bool instead of an int and takes the address_space as a parameter instead of expecting the implementations to retrieve the address_space from the page. This is particularly important for filesystems which use FS_OPS for swap. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Tested-by: Damien Le Moal <damien.lemoal@opensource.wdc.com> Acked-by: Damien Le Moal <damien.lemoal@opensource.wdc.com> Tested-by: Mike Marshall <hubcap@omnibond.com> # orangefs Tested-by: David Howells <dhowells@redhat.com> # afs
2022-03-15fs: Add aops->launder_folioMatthew Wilcox (Oracle)1-4/+4
Since the only difference between ->launder_page and ->launder_folio is the type of the pointer, these can safely use a union without affecting bisectability. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Tested-by: Damien Le Moal <damien.lemoal@opensource.wdc.com> Acked-by: Damien Le Moal <damien.lemoal@opensource.wdc.com> Tested-by: Mike Marshall <hubcap@omnibond.com> # orangefs Tested-by: David Howells <dhowells@redhat.com> # afs
2022-03-15fs: Remove aops->invalidatepageMatthew Wilcox (Oracle)1-1/+0
With all users migrated to ->invalidate_folio, remove the old operation. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Tested-by: Damien Le Moal <damien.lemoal@opensource.wdc.com> Acked-by: Damien Le Moal <damien.lemoal@opensource.wdc.com> Tested-by: Mike Marshall <hubcap@omnibond.com> # orangefs Tested-by: David Howells <dhowells@redhat.com> # afs
2022-03-15fs: Add invalidate_folio() aops methodMatthew Wilcox (Oracle)1-5/+6
This is used in preference to invalidatepage, if defined. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Tested-by: Damien Le Moal <damien.lemoal@opensource.wdc.com> Acked-by: Damien Le Moal <damien.lemoal@opensource.wdc.com> Tested-by: Mike Marshall <hubcap@omnibond.com> # orangefs Tested-by: David Howells <dhowells@redhat.com> # afs
2022-03-14fs: Convert is_partially_uptodate to foliosMatthew Wilcox (Oracle)1-5/+5
Since the uptodate property is maintained on a per-folio basis, the is_partially_uptodate method should also take a folio. Fix the types at the same time so it's clear that it returns true/false and takes the count in bytes, not blocks. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Tested-by: Damien Le Moal <damien.lemoal@opensource.wdc.com> Acked-by: Damien Le Moal <damien.lemoal@opensource.wdc.com> Tested-by: Mike Marshall <hubcap@omnibond.com> # orangefs Tested-by: David Howells <dhowells@redhat.com> # afs