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* fs: introduce new ->get_poll_head and ->poll_mask methodsChristoph Hellwig2018-05-261-0/+13
| | | | | | | | | | | | | | ->get_poll_head returns the waitqueue that the poll operation is going to sleep on. Note that this means we can only use a single waitqueue for the poll, unlike some current drivers that use two waitqueues for different events. But now that we have keyed wakeups and heavily use those for poll there aren't that many good reason left to keep the multiple waitqueues, and if there are any ->poll is still around, the driver just won't support aio poll. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
* fs: update documentation to mention __poll_t and match the codeChristoph Hellwig2018-05-261-1/+1
| | | | | | Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Merge branch 'overlayfs-linus' of ↵Linus Torvalds2017-09-131-1/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs Pull overlayfs updates from Miklos Szeredi: "This fixes d_ino correctness in readdir, which brings overlayfs on par with normal filesystems regarding inode number semantics, as long as all layers are on the same filesystem. There are also some bug fixes, one in particular (random ioctl's shouldn't be able to modify lower layers) that touches some vfs code, but of course no-op for non-overlay fs" * 'overlayfs-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs: ovl: fix false positive ESTALE on lookup ovl: don't allow writing ioctl on lower layer ovl: fix relatime for directories vfs: add flags to d_real() ovl: cleanup d_real for negative ovl: constant d_ino for non-merge dirs ovl: constant d_ino across copy up ovl: fix readdir error value ovl: check snprintf return
| * vfs: add flags to d_real()Miklos Szeredi2017-09-041-1/+1
| | | | | | | | | | | | | | Add a separate flags argument (in addition to the open flags) to control the behavior of d_real(). Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* | swap: Remove obsolete sentenceNikolay Borisov2017-08-261-3/+1
|/ | | | | | | | | Currently there are no ->swap_{in,out} method in address_space_operations sructure definition, so the statement that anything is going to be proxied through them is wrong. Signed-off-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
* Merge branch 'work.mount' of ↵Linus Torvalds2017-07-151-6/+0
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull ->s_options removal from Al Viro: "Preparations for fsmount/fsopen stuff (coming next cycle). Everything gets moved to explicit ->show_options(), killing ->s_options off + some cosmetic bits around fs/namespace.c and friends. Basically, the stuff needed to work with fsmount series with minimum of conflicts with other work. It's not strictly required for this merge window, but it would reduce the PITA during the coming cycle, so it would be nice to have those bits and pieces out of the way" * 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: isofs: Fix isofs_show_options() VFS: Kill off s_options and helpers orangefs: Implement show_options 9p: Implement show_options isofs: Implement show_options afs: Implement show_options affs: Implement show_options befs: Implement show_options spufs: Implement show_options bpf: Implement show_options ramfs: Implement show_options pstore: Implement show_options omfs: Implement show_options hugetlbfs: Implement show_options VFS: Don't use save/replace_mount_options if not using generic_show_options VFS: Provide empty name qstr VFS: Make get_filesystem() return the affected filesystem VFS: Clean up whitespace in fs/namespace.c and fs/super.c Provide a function to create a NUL-terminated string from unterminated data
| * VFS: Kill off s_options and helpersDavid Howells2017-07-111-6/+0
| | | | | | | | | | | | | | | | | | | | Kill off s_options, save/replace_mount_options() and generic_show_options() as all filesystems now implement ->show_options() for themselves. This should make it easier to implement a context-based mount where the mount options can be passed individually over a file descriptor. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | Documentation: flesh out the section in vfs.txt on storing and reporting ↵Jeff Layton2017-07-061-3/+41
|/ | | | | | | | | writeback errors Let's try to make this extra clear for fs authors. Cc: Jan Kara <jack@suse.cz> Signed-off-by: Jeff Layton <jlayton@redhat.com>
* fs: semove set but not checked AOP_FLAG_UNINTERRUPTIBLE flagTetsuo Handa2017-05-081-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | Commit afddba49d18f ("fs: introduce write_begin, write_end, and perform_write aops") introduced AOP_FLAG_UNINTERRUPTIBLE flag which was checked in pagecache_write_begin(), but that check was removed by 4e02ed4b4a2f ("fs: remove prepare_write/commit_write"). Between these two commits, commit d9414774dc0c ("cifs: Convert cifs to new aops.") added a check in cifs_write_begin(), but that check was soon removed by commit a98ee8c1c707 ("[CIFS] fix regression in cifs_write_begin/cifs_write_end"). Therefore, AOP_FLAG_UNINTERRUPTIBLE flag is checked nowhere. Let's remove this flag. This patch has no functionality changes. Link: http://lkml.kernel.org/r/1489294781-53494-1-git-send-email-penguin-kernel@I-love.SAKURA.ne.jp Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Reviewed-by: Jeff Layton <jlayton@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Cc: Nick Piggin <npiggin@gmail.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Documentation/filesystems: fix documentation for ->getattr()Eric Biggers2017-04-031-2/+1
| | | | | | | | | | Following the recent merge of statx, correct the documented prototype for the ->getattr() inode operation, and add an entry to the porting file. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* statx: Add a system call to make enhanced file info availableDavid Howells2017-03-021-1/+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>
* Merge uncontroversial parts of branch 'readlink' of ↵Linus Torvalds2016-12-171-3/+6
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs Pull partial readlink cleanups from Miklos Szeredi. This is the uncontroversial part of the readlink cleanup patch-set that simplifies the default readlink handling. Miklos and Al are still discussing the rest of the series. * git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs: vfs: make generic_readlink() static vfs: remove ".readlink = generic_readlink" assignments vfs: default to generic_readlink() vfs: replace calling i_op->readlink with vfs_readlink() proc/self: use generic_readlink ecryptfs: use vfs_get_link() bad_inode: add missing i_op initializers
| * vfs: default to generic_readlink()Miklos Szeredi2016-12-091-3/+6
| | | | | | | | | | | | | | | | | | | | If i_op->readlink is NULL, but i_op->get_link is set then vfs_readlink() defaults to calling generic_readlink(). The IOP_DEFAULT_READLINK flag indicates that the above conditions are met and the default action can be taken. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* | vfs: change d_manage() to take a struct pathIan Kent2016-12-021-1/+1
|/ | | | | | | | | | | | | | For the autofs module to be able to reliably check if a dentry is a mountpoint in a multiple namespace environment the ->d_manage() dentry operation will need to take a path argument instead of a dentry. Link: http://lkml.kernel.org/r/20161011053352.27645.83962.stgit@pluto.themaw.net Signed-off-by: Ian Kent <raven@themaw.net> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Omar Sandoval <osandov@osandov.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* fs: remove the never implemented aio_fsync file operationChristoph Hellwig2016-10-301-1/+0
| | | | | Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* Merge branch 'for-linus' of ↵Linus Torvalds2016-10-101-7/+2
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull more vfs updates from Al Viro: ">rename2() work from Miklos + current_time() from Deepa" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: fs: Replace current_fs_time() with current_time() fs: Replace CURRENT_TIME_SEC with current_time() for inode timestamps fs: Replace CURRENT_TIME with current_time() for inode timestamps fs: proc: Delete inode time initializations in proc_alloc_inode() vfs: Add current_time() api vfs: add note about i_op->rename changes to porting fs: rename "rename2" i_op to "rename" vfs: remove unused i_op->rename fs: make remaining filesystems use .rename2 libfs: support RENAME_NOREPLACE in simple_rename() fs: support RENAME_NOREPLACE for local filesystems ncpfs: fix unused variable warning
| * fs: rename "rename2" i_op to "rename"Miklos Szeredi2016-09-271-1/+1
| | | | | | | | | | | | | | | | | | Generated patch: sed -i "s/\.rename2\t/\.rename\t\t/" `git grep -wl rename2` sed -i "s/\brename2\b/rename/g" `git grep -wl rename2` Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
| * vfs: remove unused i_op->renameMiklos Szeredi2016-09-271-7/+2
| | | | | | | | | | | | No in-tree uses remain. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* | Merge branch 'work.xattr' of ↵Linus Torvalds2016-10-101-15/+30
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs xattr updates from Al Viro: "xattr stuff from Andreas This completes the switch to xattr_handler ->get()/->set() from ->getxattr/->setxattr/->removexattr" * 'work.xattr' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: vfs: Remove {get,set,remove}xattr inode operations xattr: Stop calling {get,set,remove}xattr inode operations vfs: Check for the IOP_XATTR flag in listxattr xattr: Add __vfs_{get,set,remove}xattr helpers libfs: Use IOP_XATTR flag for empty directory handling vfs: Use IOP_XATTR flag for bad-inode handling vfs: Add IOP_XATTR inode operations flag vfs: Move xattr_resolve_name to the front of fs/xattr.c ecryptfs: Switch to generic xattr handlers sockfs: Get rid of getxattr iop sockfs: getxattr: Fail with -EOPNOTSUPP for invalid attribute names kernfs: Switch to generic xattr handlers hfs: Switch to generic xattr handlers jffs2: Remove jffs2_{get,set,remove}xattr macros xattr: Remove unnecessary NULL attribute name check
| * | xattr: Stop calling {get,set,remove}xattr inode operationsAndreas Gruenbacher2016-10-071-15/+30
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | All filesystems that support xattrs by now do so via xattr handlers. They all define sb->s_xattr, and their getxattr, setxattr, and removexattr inode operations use the generic inode operations. On filesystems that don't support xattrs, the xattr inode operations are all NULL, and sb->s_xattr is also NULL. This means that we can remove the getxattr, setxattr, and removexattr inode operations and directly call the generic handlers, or better, inline expand those handlers into fs/xattr.c. Filesystems that do not support xattrs on some inodes should clear the IOP_XATTR i_opflags flag in those inodes. (Right now, some filesystems have checks to disable xattrs on some inodes in the ->list, ->get, and ->set xattr handler operations instead.) The IOP_XATTR flag is automatically cleared in inodes of filesystems that don't have xattr support. In orangefs, symlinks do have a setxattr iop but no getxattr iop. Add a check for symlinks to orangefs_inode_getxattr to preserve the current, weird behavior; that check may not be necessary though. Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | Merge branch 'for-linus' of ↵Linus Torvalds2016-10-071-1/+1
|\ \ | |/ |/| | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial Pull trivial updates from Jiri Kosina: "The usual rocket science from the trivial tree" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: tracing/syscalls: fix multiline in error message text lib/Kconfig.debug: fix DEBUG_SECTION_MISMATCH description doc: vfs: fix fadvise() sycall name x86/entry: spell EBX register correctly in documentation securityfs: fix securityfs_create_dir comment irq: Fix typo in tracepoint.xml
| * doc: vfs: fix fadvise() sycall nameAndreas Gruenbacher2016-09-291-1/+1
| | | | | | | | | | Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
* | get rid of 'parent' argument of ->d_compare()Al Viro2016-07-311-1/+1
| | | | | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | Merge branch 'work.misc' of ↵Linus Torvalds2016-07-281-19/+32
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs updates from Al Viro: "Assorted cleanups and fixes. Probably the most interesting part long-term is ->d_init() - that will have a bunch of followups in (at least) ceph and lustre, but we'll need to sort the barrier-related rules before it can get used for really non-trivial stuff. Another fun thing is the merge of ->d_iput() callers (dentry_iput() and dentry_unlink_inode()) and a bunch of ->d_compare() ones (all except the one in __d_lookup_lru())" * 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (26 commits) fs/dcache.c: avoid soft-lockup in dput() vfs: new d_init method vfs: Update lookup_dcache() comment bdev: get rid of ->bd_inodes Remove last traces of ->sync_page new helper: d_same_name() dentry_cmp(): use lockless_dereference() instead of smp_read_barrier_depends() vfs: clean up documentation vfs: document ->d_real() vfs: merge .d_select_inode() into .d_real() unify dentry_iput() and dentry_unlink_inode() binfmt_misc: ->s_root is not going anywhere drop redundant ->owner initializations ufs: get rid of redundant checks orangefs: constify inode_operations missed comment updates from ->direct_IO() prototype change file_inode(f)->i_mapping is f->f_mapping trim fsnotify hooks a bit 9p: new helper - v9fs_parent_fid() debugfs: ->d_parent is never NULL or negative ...
| * | vfs: new d_init methodMiklos Szeredi2016-07-241-0/+3
| | | | | | | | | | | | | | | | | | | | | Allow filesystem to initialize dentry at allocation time. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
| * | Merge branch 'd_real' of ↵Al Viro2016-06-301-14/+26
| |\ \ | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs into work.misc
| | * | vfs: clean up documentationMiklos Szeredi2016-06-301-16/+8
| | | | | | | | | | | | | | | | Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
| | * | vfs: document ->d_real()Miklos Szeredi2016-06-301-0/+20
| | |/ | | | | | | | | | | | | | | | | | | Add missing documentation for the d_op->d_real() method and d_real() helper. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
| * | Remove last traces of ->sync_pageMatthew Wilcox2016-06-301-5/+3
| |/ | | | | | | | | | | | | | | Commit 7eaceaccab5f removed ->sync_page, but a few mentions of it still existed in documentation and comments, Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | mm: migrate: support non-lru movable page migrationMinchan Kim2016-07-261-0/+11
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We have allowed migration for only LRU pages until now and it was enough to make high-order pages. But recently, embedded system(e.g., webOS, android) uses lots of non-movable pages(e.g., zram, GPU memory) so we have seen several reports about troubles of small high-order allocation. For fixing the problem, there were several efforts (e,g,. enhance compaction algorithm, SLUB fallback to 0-order page, reserved memory, vmalloc and so on) but if there are lots of non-movable pages in system, their solutions are void in the long run. So, this patch is to support facility to change non-movable pages with movable. For the feature, this patch introduces functions related to migration to address_space_operations as well as some page flags. If a driver want to make own pages movable, it should define three functions which are function pointers of struct address_space_operations. 1. bool (*isolate_page) (struct page *page, isolate_mode_t mode); What VM expects on isolate_page function of driver is to return *true* if driver isolates page successfully. On returing true, VM marks the page as PG_isolated so concurrent isolation in several CPUs skip the page for isolation. If a driver cannot isolate the page, it should return *false*. Once page is successfully isolated, VM uses page.lru fields so driver shouldn't expect to preserve values in that fields. 2. int (*migratepage) (struct address_space *mapping, struct page *newpage, struct page *oldpage, enum migrate_mode); After isolation, VM calls migratepage of driver with isolated page. The function of migratepage is to move content of the old page to new page and set up fields of struct page newpage. Keep in mind that you should indicate to the VM the oldpage is no longer movable via __ClearPageMovable() under page_lock if you migrated the oldpage successfully and returns 0. If driver cannot migrate the page at the moment, driver can return -EAGAIN. On -EAGAIN, VM will retry page migration in a short time because VM interprets -EAGAIN as "temporal migration failure". On returning any error except -EAGAIN, VM will give up the page migration without retrying in this time. Driver shouldn't touch page.lru field VM using in the functions. 3. void (*putback_page)(struct page *); If migration fails on isolated page, VM should return the isolated page to the driver so VM calls driver's putback_page with migration failed page. In this function, driver should put the isolated page back to the own data structure. 4. non-lru movable page flags There are two page flags for supporting non-lru movable page. * PG_movable Driver should use the below function to make page movable under page_lock. void __SetPageMovable(struct page *page, struct address_space *mapping) It needs argument of address_space for registering migration family functions which will be called by VM. Exactly speaking, PG_movable is not a real flag of struct page. Rather than, VM reuses page->mapping's lower bits to represent it. #define PAGE_MAPPING_MOVABLE 0x2 page->mapping = page->mapping | PAGE_MAPPING_MOVABLE; so driver shouldn't access page->mapping directly. Instead, driver should use page_mapping which mask off the low two bits of page->mapping so it can get right struct address_space. For testing of non-lru movable page, VM supports __PageMovable function. However, it doesn't guarantee to identify non-lru movable page because page->mapping field is unified with other variables in struct page. As well, if driver releases the page after isolation by VM, page->mapping doesn't have stable value although it has PAGE_MAPPING_MOVABLE (Look at __ClearPageMovable). But __PageMovable is cheap to catch whether page is LRU or non-lru movable once the page has been isolated. Because LRU pages never can have PAGE_MAPPING_MOVABLE in page->mapping. It is also good for just peeking to test non-lru movable pages before more expensive checking with lock_page in pfn scanning to select victim. For guaranteeing non-lru movable page, VM provides PageMovable function. Unlike __PageMovable, PageMovable functions validates page->mapping and mapping->a_ops->isolate_page under lock_page. The lock_page prevents sudden destroying of page->mapping. Driver using __SetPageMovable should clear the flag via __ClearMovablePage under page_lock before the releasing the page. * PG_isolated To prevent concurrent isolation among several CPUs, VM marks isolated page as PG_isolated under lock_page. So if a CPU encounters PG_isolated non-lru movable page, it can skip it. Driver doesn't need to manipulate the flag because VM will set/clear it automatically. Keep in mind that if driver sees PG_isolated page, it means the page have been isolated by VM so it shouldn't touch page.lru field. PG_isolated is alias with PG_reclaim flag so driver shouldn't use the flag for own purpose. [opensource.ganesh@gmail.com: mm/compaction: remove local variable is_lru] Link: http://lkml.kernel.org/r/20160618014841.GA7422@leo-test Link: http://lkml.kernel.org/r/1464736881-24886-3-git-send-email-minchan@kernel.org Signed-off-by: Gioh Kim <gi-oh.kim@profitbricks.com> Signed-off-by: Minchan Kim <minchan@kernel.org> Signed-off-by: Ganesh Mahendran <opensource.ganesh@gmail.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Cc: Rik van Riel <riel@redhat.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Hugh Dickins <hughd@google.com> Cc: Rafael Aquini <aquini@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: John Einar Reitan <john.reitan@foss.arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* direct-io: eliminate the offset argument to ->direct_IOChristoph Hellwig2016-05-011-1/+1
| | | | | | | | Including blkdev_direct_IO and dax_do_io. It has to be ki_pos to actually work, so eliminate the superflous argument. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* mm, fs: remove remaining PAGE_CACHE_* and page_cache_{get,release} usageKirill A. Shutemov2016-04-041-2/+2
| | | | | | | | | Mostly direct substitution with occasional adjustment or removing outdated comments. Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* switch ->get_link() to delayed_call, kill ->put_link()Al Viro2015-12-301-11/+10
| | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* fs: Remove ext3 filesystem driverJan Kara2015-07-231-1/+1
| | | | | | | | | | | | | The functionality of ext3 is fully supported by ext4 driver. Major distributions (SUSE, RedHat) already use ext4 driver to handle ext3 filesystems for quite some time. There is some ugliness in mm resulting from jbd cleaning buffers in a dirty page without cleaning page dirty bit and also support for buffer bouncing in the block layer when stable pages are required is there only because of jbd. So let's remove the ext3 driver. This saves us some 28k lines of duplicated code. Acked-by: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Jan Kara <jack@suse.cz>
* Merge tag 'docs-for-linus' of git://git.lwn.net/linux-2.6Linus Torvalds2015-06-241-6/+11
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull documentation updates from Jonathan Corbet: "The main thing here is Ingo's big subdirectory documenting feature support for each architecture. Beyond that, it's the usual pile of fixes, tweaks, and small additions" * tag 'docs-for-linus' of git://git.lwn.net/linux-2.6: (79 commits) doc:md: fix typo in md.txt. Documentation/mic/mpssd: don't build x86 userspace when cross compiling Documentation/prctl: don't build tsc tests when cross compiling Documentation/vDSO: don't build tests when cross compiling Doc:ABI/testing: Fix typo in sysfs-bus-fcoe Doc: Docbook: Change wikipedia's URL from http to https in scsi.tmpl Doc: Change wikipedia's URL from http to https Documentation/kernel-parameters: add missing pciserial to the earlyprintk Doc:pps: Fix typo in pps.txt kbuild : Fix documentation of INSTALL_HDR_PATH Documentation: filesystems: updated struct file_operations documentation in vfs.txt kbuild: edit explanation of clean-files variable Doc: ja_JP: Fix typo in HOWTO Move freefall program from Documentation/ to tools/ Documentation: ARM: EXYNOS: Describe boot loaders interface Doc:nfc: Fix typo in nfc-hci.txt vfs: Minor documentation fix Doc: networking: txtimestamp: fix printf format warning Documentation, intel_pstate: Improve legacy mode internal governors description Documentation: extend use case for EXPORT_SYMBOL_GPL() ...
| * Documentation: filesystems: updated struct file_operations documentation in ↵Thomas de Beauchene2015-06-081-6/+11
| | | | | | | | | | | | | | | | | | | | vfs.txt Updated struct file_operations documentation in vfs.txt to match current implementation Signed-off-by: Thomas de Beauchene <chauvo_t@epitech.eu> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
* | update Documentation/filesystems/ regarding the follow_link/put_link changesAl Viro2015-05-151-8/+10
| | | | | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | switch ->put_link() from dentry to inodeAl Viro2015-05-111-1/+1
| | | | | | | | | | | | | | only one instance looks at that argument at all; that sole exception wants inode rather than dentry. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | don't pass nameidata to ->follow_link()Al Viro2015-05-101-1/+1
| | | | | | | | | | | | | | its only use is getting passed to nd_jump_link(), which can obtain it from current->nameidata Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | new ->follow_link() and ->put_link() calling conventionsAl Viro2015-05-101-2/+2
|/ | | | | | | | | | | | | | | | | | | a) instead of storing the symlink body (via nd_set_link()) and returning an opaque pointer later passed to ->put_link(), ->follow_link() _stores_ that opaque pointer (into void * passed by address by caller) and returns the symlink body. Returning ERR_PTR() on error, NULL on jump (procfs magic symlinks) and pointer to symlink body for normal symlinks. Stored pointer is ignored in all cases except the last one. Storing NULL for opaque pointer (or not storing it at all) means no call of ->put_link(). b) the body used to be passed to ->put_link() implicitly (via nameidata). Now only the opaque pointer is. In the cases when we used the symlink body to free stuff, ->follow_link() now should store it as opaque pointer in addition to returning it. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* direct_IO: remove rw from a_ops->direct_IO()Omar Sandoval2015-04-111-1/+1
| | | | | | | Now that no one is using rw, remove it completely. Signed-off-by: Omar Sandoval <osandov@osandov.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* ->aio_read and ->aio_write removedAl Viro2015-04-111-6/+0
| | | | | | no remaining users Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* vfs: remove get_xip_memMatthew Wilcox2015-02-161-7/+0
| | | | | | | | | | | | | | | | | | | | | | All callers of get_xip_mem() are now gone. Remove checks for it, initialisers of it, documentation of it and the only implementation of it. Also remove mm/filemap_xip.c as it is now empty. Also remove documentation of the long-gone get_xip_page(). Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com> Cc: Andreas Dilger <andreas.dilger@intel.com> Cc: Boaz Harrosh <boaz@plexistor.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Dave Chinner <david@fromorbit.com> Cc: Jan Kara <jack@suse.cz> Cc: Jens Axboe <axboe@kernel.dk> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Ross Zwisler <ross.zwisler@linux.intel.com> Cc: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge tag 'trace-seq-file-cleanup' of ↵Al Viro2014-11-191-1/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace into for-next Pull the beginning of seq_file cleanup from Steven: "I'm looking to clean up the seq_file code and to eventually merge the trace_seq code with seq_file as well, since they basically do the same thing. Part of this process is to remove the return code of seq_printf() and friends as they are rather inconsistent. It is better to use the new function seq_has_overflowed() if you want to stop processing when the buffer is full. Note, if the buffer is full, the seq_file code will throw away the contents, allocate a bigger buffer, and then call your code again to fill in the data. The only thing that breaking out of the function early does is to save a little time which is probably never noticed. I started with patches from Joe Perches and modified them as well. There's many more places that need to be updated before we can convert seq_printf() and friends to return void. But this patch set introduces the seq_has_overflowed() and does some initial updates."
| * fs: Convert show_fdinfo functions to voidJoe Perches2014-11-051-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | seq_printf functions shouldn't really check the return value. Checking seq_has_overflowed() occasionally is used instead. Update vfs documentation. Link: http://lkml.kernel.org/p/e37e6e7b76acbdcc3bb4ab2a57c8f8ca1ae11b9a.1412031505.git.joe@perches.com Cc: David S. Miller <davem@davemloft.net> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Joe Perches <joe@perches.com> [ did a few clean ups ] Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* | vfs: add i_op->dentry_open()Miklos Szeredi2014-10-241-0/+7
|/ | | | | | | Add a new inode operation i_op->dentry_open(). This is for stacked filesystems that want to return a struct file from a different filesystem. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
* Merge branch 'for-linus' of ↵Linus Torvalds2014-10-131-1/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs updates from Al Viro: "The big thing in this pile is Eric's unmount-on-rmdir series; we finally have everything we need for that. The final piece of prereqs is delayed mntput() - now filesystem shutdown always happens on shallow stack. Other than that, we have several new primitives for iov_iter (Matt Wilcox, culled from his XIP-related series) pushing the conversion to ->read_iter()/ ->write_iter() a bit more, a bunch of fs/dcache.c cleanups and fixes (including the external name refcounting, which gives consistent behaviour of d_move() wrt procfs symlinks for long and short names alike) and assorted cleanups and fixes all over the place. This is just the first pile; there's a lot of stuff from various people that ought to go in this window. Starting with unionmount/overlayfs mess... ;-/" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (60 commits) fs/file_table.c: Update alloc_file() comment vfs: Deduplicate code shared by xattr system calls operating on paths reiserfs: remove pointless forward declaration of struct nameidata don't need that forward declaration of struct nameidata in dcache.h anymore take dname_external() into fs/dcache.c let path_init() failures treated the same way as subsequent link_path_walk() fix misuses of f_count() in ppp and netlink ncpfs: use list_for_each_entry() for d_subdirs walk vfs: move getname() from callers to do_mount() gfs2_atomic_open(): skip lookups on hashed dentry [infiniband] remove pointless assignments gadgetfs: saner API for gadgetfs_create_file() f_fs: saner API for ffs_sb_create_file() jfs: don't hash direct inode [s390] remove pointless assignment of ->f_op in vmlogrdr ->open() ecryptfs: ->f_op is never NULL android: ->f_op is never NULL nouveau: __iomem misannotations missing annotation in fs/file.c fs: namespace: suppress 'may be used uninitialized' warnings ...
| * vfs: fix typo in s_op->alloc_inode() documentationKirill Smelkov2014-10-091-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | The function which calls s_op->alloc_inode() is not inode_alloc(), but instead alloc_inode() which lives in fs/inode.c . The typo was there from the beginning from 5ea626aa (VFS: update documentation, 2005) - there was no standalone inode_alloc() for the whole kernel history. Cc: Pekka Enberg <penberg@kernel.org> Signed-off-by: Kirill Smelkov <kirr@nexedi.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | locks: move i_lock acquisition into generic_*_lease handlersJeff Layton2014-10-071-2/+3
| | | | | | | | | | | | | | | | | | Now that we have a saner internal API for managing leases, we no longer need to mandate that the inode->i_lock be held over most of the lease code. Push it down into generic_add_lease and generic_delete_lease. Signed-off-by: Jeff Layton <jlayton@primarydata.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
* | locks: plumb a "priv" pointer into the setlease routinesJeff Layton2014-10-071-1/+1
|/ | | | | | | | | | | | | | | In later patches, we're going to add a new lock_manager_operation to finish setting up the lease while still holding the i_lock. To do this, we'll need to pass a little bit of info in the fcntl setlease case (primarily an fasync structure). Plumb the extra pointer into there in advance of that. We declare this pointer as a void ** to make it clear that this is private info, and that the caller isn't required to set this unless the lm_setup specifically requires it. Signed-off-by: Jeff Layton <jlayton@primarydata.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
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