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* License cleanup: add SPDX GPL-2.0 license identifier to files with no licenseGreg Kroah-Hartman2017-11-021-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* fs: Provide __inode_get_bytes()Jan Kara2017-08-171-1/+1
| | | | | | | | Provide helper __inode_get_bytes() which assumes i_lock is already acquired. Quota code will need this to be able to use i_lock to protect consistency of quota accounting information and inode usage. Signed-off-by: Jan Kara <jack@suse.cz>
* ufs: restore maintaining ->i_blocksAl Viro2017-06-091-0/+1
| | | | | Cc: stable@vger.kernel.org Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* Merge branch 'work.compat' of ↵Linus Torvalds2017-05-021-0/+86
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull fs/compat.c cleanups from Al Viro: "More moving of compat syscalls from fs/compat.c to fs/*.c where the native counterparts live. And death to compat_sys_getdents64() - the only architecture that used to need it was ia64, and _that_ has lost biarch support quite a few years ago" * 'work.compat' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: fs/compat.c: trim unused includes move compat_rw_copy_check_uvector() over to fs/read_write.c fhandle: move compat syscalls from compat.c open: move compat syscalls from compat.c stat: move compat syscalls from compat.c fcntl: move compat syscalls from compat.c readdir: move compat syscalls from compat.c statfs: move compat syscalls from compat.c utimes: move compat syscalls from compat.c move compat select-related syscalls to fs/select.c Remove compat_sys_getdents64()
| * stat: move compat syscalls from compat.cAl Viro2017-04-171-0/+86
| | | | | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | statx: correct error handling of NULL pathnameMichael Kerrisk (man-pages)2017-04-271-2/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The change in commit 1e2f82d1e9d1 ("statx: Kill fd-with-NULL-path support in favour of AT_EMPTY_PATH") to error on a NULL pathname to statx() is inconsistent. It results in the error EINVAL for a NULL pathname. Other system calls with similar APIs (fchownat(), fstatat(), linkat()), return EFAULT. The solution is simply to remove the EINVAL check. As I already pointed out in [1], user_path_at*() and filename_lookup() will handle the NULL pathname as per the other APIs, to correctly produce the error EFAULT. [1] https://lkml.org/lkml/2017/4/26/561 Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com> Cc: David Howells <dhowells@redhat.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Eric Sandeen <sandeen@sandeen.net> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | statx: Kill fd-with-NULL-path support in favour of AT_EMPTY_PATHDavid Howells2017-04-261-7/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | With the new statx() syscall, the following both allow the attributes of the file attached to a file descriptor to be retrieved: statx(dfd, NULL, 0, ...); and: statx(dfd, "", AT_EMPTY_PATH, ...); Change the code to reject the first option, though this means copying the path and engaging pathwalk for the fstat() equivalent. dfd can be a non-directory provided path is "". [ The timing of this isn't wonderful, but applying this now before we have statx() in any released kernel, before anybody starts using the NULL special case. - Linus ] Fixes: a528d35e8bfc ("statx: Add a system call to make enhanced file info available") Reported-by: Michael Kerrisk <mtk.manpages@gmail.com> Signed-off-by: David Howells <dhowells@redhat.com> cc: Eric Sandeen <sandeen@sandeen.net> cc: fstests@vger.kernel.org cc: linux-api@vger.kernel.org cc: linux-man@vger.kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | statx: Include a mask for stx_attributes in struct statxDavid Howells2017-04-031-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | Include a mask in struct stat to indicate which bits of stx_attributes the filesystem actually supports. This would also be useful if we add another system call that allows you to do a 'bulk attribute set' and pass in a statx struct with the masks appropriately set to say what you want to set. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | statx: Reserve the top bit of the mask for future struct expansionDavid Howells2017-04-031-0/+2
| | | | | | | | | | | | | | | | | | | | Reserve the top bit of the mask for future expansion of the statx struct and give an error if statx() sees it set. All the other bits are ignored if we see them set but don't support the bit; we just clear the bit in the returned mask. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | statx: optimize copy of struct statx to userspaceEric Biggers2017-04-031-42/+32
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | I found that statx() was significantly slower than stat(). As a microbenchmark, I compared 10,000,000 invocations of fstat() on a tmpfs file to the same with statx() passed a NULL path: $ time ./stat_benchmark real 0m1.464s user 0m0.275s sys 0m1.187s $ time ./statx_benchmark real 0m5.530s user 0m0.281s sys 0m5.247s statx is expected to be a little slower than stat because struct statx is larger than struct stat, but not by *that* much. It turns out that most of the overhead was in copying struct statx to userspace, mostly in all the stac/clac instructions that got generated for each __put_user() call. (This was on x86_64, but some other architectures, e.g. arm64, have something similar now too.) stat() instead initializes its struct on the stack and copies it to userspace with a single call to copy_to_user(). This turns out to be much faster, and changing statx to do this makes it almost as fast as stat: $ time ./statx_benchmark real 0m1.624s user 0m0.270s sys 0m1.354s For zeroing the reserved fields, start by zeroing the full struct with memset. This makes it clear that every byte copied to userspace is initialized, even implicit padding bytes (though there are none currently). In the scenarios I tested, it also performed the same as a designated initializer. Manually initializing each field was still slightly faster, but would have been more error-prone and less verifiable. Also rename statx_set_result() to cp_statx() for consistency with cp_old_stat() et al., and make it noinline so that struct statx doesn't add to the stack usage during the main portion of the syscall execution. 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: remove incorrect part of vfs_statx() commentEric Biggers2017-04-031-3/+0
| | | | | | | | | | | | | | | | | | | | | | | | request_mask and query_flags are function arguments, not passed in struct kstat. So remove the part of the comment which claims otherwise. This was apparently left over from an earlier version of the statx patch. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | statx: reject unknown flags when using NULL pathEric Biggers2017-04-031-1/+5
|/ | | | | | | | | | | | | | | | | | | | | | The statx() system call currently accepts unknown flags when called with a NULL path to operate on a file descriptor. Left unchanged, this could make it hard to introduce new query flags in the future, since applications may not be able to tell whether a given flag is supported. Fix this by failing the system call with EINVAL if any flags other than KSTAT_QUERY_FLAGS are specified in combination with a NULL path. Arguably, we could still permit known lookup-related flags such as AT_SYMLINK_NOFOLLOW. However, that would be inconsistent with how sys_utimensat() behaves when passed a NULL path, which seems to be the closest precedent. And given that the NULL path case is (I believe) mainly intended to be used to implement a wrapper function like fstatx() that doesn't have a path argument, I think rejecting lookup-related flags too is probably the best choice. 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>
* Merge branch 'rebased-statx' of ↵Linus Torvalds2017-03-031-38/+176
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs 'statx()' update from Al Viro. This adds the new extended stat() interface that internally subsumes our previous stat interfaces, and allows user mode to specify in more detail what kind of information it wants. It also allows for some explicit synchronization information to be passed to the filesystem, which can be relevant for network filesystems: is the cached value ok, or do you need open/close consistency, or what? From David Howells. Andreas Dilger points out that the first version of the extended statx interface was posted June 29, 2010: https://www.spinics.net/lists/linux-fsdevel/msg33831.html * 'rebased-statx' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: statx: Add a system call to make enhanced file info available
| * statx: Add a system call to make enhanced file info availableDavid Howells2017-03-021-38/+176
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | sched/headers: Prepare to remove <linux/cred.h> inclusion from <linux/sched.h>Ingo Molnar2017-03-021-0/+1
|/ | | | | | | | | | | | | | | | Add #include <linux/cred.h> dependencies to all .c files rely on sched.h doing that for them. Note that even if the count where we need to add extra headers seems high, it's still a net win, because <linux/sched.h> is included in over 2,200 files ... Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* fs: add i_blocksize()Fabian Frederick2017-02-271-1/+1
| | | | | | | | | | | | | | | | | | | | | Replace all 1 << inode->i_blkbits and (1 << inode->i_blkbits) in fs branch. This patch also fixes multiple checkpatch warnings: WARNING: Prefer 'unsigned int' to bare use of 'unsigned' Thanks to Andrew Morton for suggesting more appropriate function instead of macro. [geliangtang@gmail.com: truncate: use i_blocksize()] Link: http://lkml.kernel.org/r/9c8b2cd83c8f5653805d43debde9fa8817e02fc4.1484895804.git.geliangtang@gmail.com Link: http://lkml.kernel.org/r/1481319905-10126-1-git-send-email-fabf@skynet.be Signed-off-by: Fabian Frederick <fabf@skynet.be> Signed-off-by: Geliang Tang <geliangtang@gmail.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Ross Zwisler <ross.zwisler@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Replace <asm/uaccess.h> with <linux/uaccess.h> globallyLinus Torvalds2016-12-241-1/+1
| | | | | | | | | | | | | This was entirely automated, using the script by Al: PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>' sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \ $(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h) to do the replacement at the end of the merge window. Requested-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* vfs: replace calling i_op->readlink with vfs_readlink()Miklos Szeredi2016-12-091-3/+5
| | | | | | | Also check d_is_symlink() in callers instead of inode->i_op->readlink because following patches will allow NULL ->readlink for symlinks. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* fs/stat.c: drop the last new_valid_dev checkYaowei Bai2016-01-161-1/+1
| | | | | | | | | | | | | | New_valid_dev() always returns true, so that's unnecessary to perform new_valid_dev() checks in some filesystems. Most checks of new_valid_dev() have been removed so let's drop this last one and then we can remove new_valid_dev() from the source code. No functional change. Signed-off-by: Yaowei Bai <baiyaowei@cmss.chinamobile.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>
* fs/stat.c: remove unnecessary new_valid_dev() checkYaowei Bai2015-11-091-2/+0
| | | | | | | | | | new_valid_dev() always returns 1, so the !new_valid_dev() check is not needed. Remove it. Signed-off-by: Yaowei Bai <bywxiaobai@163.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* VFS: assorted d_backing_inode() annotationsDavid Howells2015-04-151-2/+2
| | | | | Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* switch security_inode_getattr() to struct path *Al Viro2015-04-111-1/+1
| | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* vfs: split out vfs_getattr_nosecJ. Bruce Fields2013-11-091-6/+25
| | | | | | | | The filehandle lookup code wants this version of getattr. Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: J. Bruce Fields <bfields@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* quota: provide interface for readding allocated space into reserved spaceJan Kara2013-08-171-2/+9
| | | | | | | | | ext4 needs to convert allocated (metadata) blocks back into blocks reserved for delayed allocation. Add functions into quota code for supporting such operation. Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
* switch vfs_getattr() to struct pathAl Viro2013-02-261-7/+6
| | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* vfs: fix readlinkat to retry on ESTALEJeff Layton2012-12-201-1/+7
| | | | | Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* vfs: make fstatat retry on ESTALE errors from getattr callJeff Layton2012-12-201-2/+6
| | | | | Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* Merge branch 'for-linus' of ↵Linus Torvalds2012-10-021-5/+5
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs update from Al Viro: - big one - consolidation of descriptor-related logics; almost all of that is moved to fs/file.c (BTW, I'm seriously tempted to rename the result to fd.c. As it is, we have a situation when file_table.c is about handling of struct file and file.c is about handling of descriptor tables; the reasons are historical - file_table.c used to be about a static array of struct file we used to have way back). A lot of stray ends got cleaned up and converted to saner primitives, disgusting mess in android/binder.c is still disgusting, but at least doesn't poke so much in descriptor table guts anymore. A bunch of relatively minor races got fixed in process, plus an ext4 struct file leak. - related thing - fget_light() partially unuglified; see fdget() in there (and yes, it generates the code as good as we used to have). - also related - bits of Cyrill's procfs stuff that got entangled into that work; _not_ all of it, just the initial move to fs/proc/fd.c and switch of fdinfo to seq_file. - Alex's fs/coredump.c spiltoff - the same story, had been easier to take that commit than mess with conflicts. The rest is a separate pile, this was just a mechanical code movement. - a few misc patches all over the place. Not all for this cycle, there'll be more (and quite a few currently sit in akpm's tree)." Fix up trivial conflicts in the android binder driver, and some fairly simple conflicts due to two different changes to the sock_alloc_file() interface ("take descriptor handling from sock_alloc_file() to callers" vs "net: Providing protocol type via system.sockprotoname xattr of /proc/PID/fd entries" adding a dentry name to the socket) * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (72 commits) MAX_LFS_FILESIZE should be a loff_t compat: fs: Generic compat_sys_sendfile implementation fs: push rcu_barrier() from deactivate_locked_super() to filesystems btrfs: reada_extent doesn't need kref for refcount coredump: move core dump functionality into its own file coredump: prevent double-free on an error path in core dumper usb/gadget: fix misannotations fcntl: fix misannotations ceph: don't abuse d_delete() on failure exits hypfs: ->d_parent is never NULL or negative vfs: delete surplus inode NULL check switch simple cases of fget_light to fdget new helpers: fdget()/fdput() switch o2hb_region_dev_write() to fget_light() proc_map_files_readdir(): don't bother with grabbing files make get_file() return its argument vhost_set_vring(): turn pollstart/pollstop into bool switch prctl_set_mm_exe_file() to fget_light() switch xfs_find_handle() to fget_light() switch xfs_swapext() to fget_light() ...
| * switch simple cases of fget_light to fdgetAl Viro2012-09-261-5/+5
| | | | | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | Merge tag 'arm64-for-linus' of ↵Linus Torvalds2012-10-011-2/+2
|\ \ | |/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/cmarinas/linux-aarch64 Pull arm64 support from Catalin Marinas: "Linux support for the 64-bit ARM architecture (AArch64) Features currently supported: - 39-bit address space for user and kernel (each) - 4KB and 64KB page configurations - Compat (32-bit) user applications (ARMv7, EABI only) - Flattened Device Tree (mandated for all AArch64 platforms) - ARM generic timers" * tag 'arm64-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/cmarinas/linux-aarch64: (35 commits) arm64: ptrace: remove obsolete ptrace request numbers from user headers arm64: Do not set the SMP/nAMP processor bit arm64: MAINTAINERS update arm64: Build infrastructure arm64: Miscellaneous header files arm64: Generic timers support arm64: Loadable modules arm64: Miscellaneous library functions arm64: Performance counters support arm64: Add support for /proc/sys/debug/exception-trace arm64: Debugging support arm64: Floating point and SIMD arm64: 32-bit (compat) applications support arm64: User access library functions arm64: Signal handling support arm64: VDSO support arm64: System calls handling arm64: ELF definitions arm64: SMP support arm64: DMA mapping API ...
| * fs: Build sys_stat64() and friends if __ARCH_WANT_COMPAT_STAT64Catalin Marinas2012-09-141-2/+2
| | | | | | | | | | | | | | | | | | On AArch64 Linux, we want the sys_stat64() and related functions for compat support but do not need the generic struct stat64, enabled automatically if __ARCH_WANT_STAT64. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Arnd Bergmann <arnd@arndb.de>
* | vfs: make O_PATH file descriptors usable for 'fstat()'Linus Torvalds2012-09-141-1/+1
|/ | | | | | | | | | | | | | | | | | We already use them for openat() and friends, but fstat() also wants to be able to use O_PATH file descriptors. This should make it more directly comparable to the O_SEARCH of Solaris. Note that you could already do the same thing with "fstatat()" and an empty path, but just doing "fstat()" directly is simpler and faster, so there is no reason not to just allow it directly. See also commit 332a2e1244bd, which did the same thing for fchdir, for the same reasons. Reported-by: ольга крыжановская <olga.kryzhanovska@gmail.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: stable@kernel.org # O_PATH introduced in 3.0+ Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge branch 'for-linus' of ↵Linus Torvalds2012-05-231-6/+6
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace Pull user namespace enhancements from Eric Biederman: "This is a course correction for the user namespace, so that we can reach an inexpensive, maintainable, and reasonably complete implementation. Highlights: - Config guards make it impossible to enable the user namespace and code that has not been converted to be user namespace safe. - Use of the new kuid_t type ensures the if you somehow get past the config guards the kernel will encounter type errors if you enable user namespaces and attempt to compile in code whose permission checks have not been updated to be user namespace safe. - All uids from child user namespaces are mapped into the initial user namespace before they are processed. Removing the need to add an additional check to see if the user namespace of the compared uids remains the same. - With the user namespaces compiled out the performance is as good or better than it is today. - For most operations absolutely nothing changes performance or operationally with the user namespace enabled. - The worst case performance I could come up with was timing 1 billion cache cold stat operations with the user namespace code enabled. This went from 156s to 164s on my laptop (or 156ns to 164ns per stat operation). - (uid_t)-1 and (gid_t)-1 are reserved as an internal error value. Most uid/gid setting system calls treat these value specially anyway so attempting to use -1 as a uid would likely cause entertaining failures in userspace. - If setuid is called with a uid that can not be mapped setuid fails. I have looked at sendmail, login, ssh and every other program I could think of that would call setuid and they all check for and handle the case where setuid fails. - If stat or a similar system call is called from a context in which we can not map a uid we lie and return overflowuid. The LFS experience suggests not lying and returning an error code might be better, but the historical precedent with uids is different and I can not think of anything that would break by lying about a uid we can't map. - Capabilities are localized to the current user namespace making it safe to give the initial user in a user namespace all capabilities. My git tree covers all of the modifications needed to convert the core kernel and enough changes to make a system bootable to runlevel 1." Fix up trivial conflicts due to nearby independent changes in fs/stat.c * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (46 commits) userns: Silence silly gcc warning. cred: use correct cred accessor with regards to rcu read lock userns: Convert the move_pages, and migrate_pages permission checks to use uid_eq userns: Convert cgroup permission checks to use uid_eq userns: Convert tmpfs to use kuid and kgid where appropriate userns: Convert sysfs to use kgid/kuid where appropriate userns: Convert sysctl permission checks to use kuid and kgids. userns: Convert proc to use kuid/kgid where appropriate userns: Convert ext4 to user kuid/kgid where appropriate userns: Convert ext3 to use kuid/kgid where appropriate userns: Convert ext2 to use kuid/kgid where appropriate. userns: Convert devpts to use kuid/kgid where appropriate userns: Convert binary formats to use kuid/kgid where appropriate userns: Add negative depends on entries to avoid building code that is userns unsafe userns: signal remove unnecessary map_cred_ns userns: Teach inode_capable to understand inodes whose uids map to other namespaces. userns: Fail exec for suid and sgid binaries with ids outside our user namespace. userns: Convert stat to return values mapped from kuids and kgids userns: Convert user specfied uids and gids in chown into kuids and kgid userns: Use uid_eq gid_eq helpers when comparing kuids and kgids in the vfs ...
| * userns: Convert stat to return values mapped from kuids and kgidsEric W. Biederman2012-05-151-6/+6
| | | | | | | | | | | | | | | | | | - Store uids and gids with kuid_t and kgid_t in struct kstat - Convert uid and gids to userspace usable values with from_kuid and from_kgid Acked-by: Serge Hallyn <serge.hallyn@canonical.com> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
* | Merge branch 'vfs-cleanups' (random vfs cleanups)Linus Torvalds2012-05-211-2/+3
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This teaches vfs_fstat() to use the appropriate f[get|put]_light functions, allowing it to avoid some unnecessary locking for the common case. More noticeably, it also cleans up and simplifies the "getname_flags()" function, which now relies on the architecture strncpy_from_user() doing all the user access checks properly, instead of hacking around the fact that on x86 it didn't use to do it right (see commit 92ae03f2ef99: "x86: merge 32/64-bit versions of 'strncpy_from_user()' and speed it up"). * vfs-cleanups: VFS: make vfs_fstat() use f[get|put]_light() VFS: clean up and simplify getname_flags() x86: make word-at-a-time strncpy_from_user clear bytes at the end
| * | VFS: make vfs_fstat() use f[get|put]_light()Linus Torvalds2012-04-281-2/+3
| |/ | | | | | | | | | | | | Use the *_light() versions that properly avoid doing the file user count updates when they are unnecessary. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | vfs: don't force a big memset of stat data just to clear padding fieldsLinus Torvalds2012-05-061-2/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Admittedly this is something that the compiler should be able to just do for us, but gcc just isn't that smart. And trying to use a structure initializer (which would get us the right semantics) ends up resulting in gcc allocating stack space for _two_ 'struct stat', and then copying one into the other. So do it by hand - just have a per-architecture macro that initializes the padding fields. And if the architecture doesn't provide one, fall back to the old behavior of just doing the whole memset() first. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | vfs: de-crapify "cp_new_stat()" functionLinus Torvalds2012-05-061-18/+14
|/ | | | | | | | | | It's an unreadable mess of 32-bit vs 64-bit #ifdef's that mostly follow a rather simple pattern. Make a helper #define to handle that pattern, in the process making the code both shorter and more readable. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge tag 'module-for-3.4' of ↵Linus Torvalds2012-03-241-1/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux Pull cleanup of fs/ and lib/ users of module.h from Paul Gortmaker: "Fix up files in fs/ and lib/ dirs to only use module.h if they really need it. These are trivial in scope vs the work done previously. We now have things where any few remaining cleanups can be farmed out to arch or subsystem maintainers, and I have done so when possible. What is remaining here represents the bits that don't clearly lie within a single arch/subsystem boundary, like the fs dir and the lib dir. Some duplicate includes arising from overlapping fixes from independent subsystem maintainer submissions are also quashed." Fix up trivial conflicts due to clashes with other include file cleanups (including some due to the previous bug.h cleanup pull). * tag 'module-for-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux: lib: reduce the use of module.h wherever possible fs: reduce the use of module.h wherever possible includecheck: delete any duplicate instances of module.h
| * fs: reduce the use of module.h wherever possiblePaul Gortmaker2012-02-281-1/+1
| | | | | | | | | | | | | | | | | | | | For files only using THIS_MODULE and/or EXPORT_SYMBOL, map them onto including export.h -- or if the file isn't even using those, then just delete the include. Fix up any implicit include dependencies that were being masked by module.h along the way. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
* | switch touch_atime to struct pathAl Viro2012-03-201-1/+1
|/ | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* readlinkat: ensure we return ENOENT for the empty pathname for normal lookupsAndy Whitcroft2011-11-021-2/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since the commit below which added O_PATH support to the *at() calls, the error return for readlink/readlinkat for the empty pathname has switched from ENOENT to EINVAL: commit 65cfc6722361570bfe255698d9cd4dccaf47570d Author: Al Viro <viro@zeniv.linux.org.uk> Date: Sun Mar 13 15:56:26 2011 -0400 readlinkat(), fchownat() and fstatat() with empty relative pathnames This is both unexpected for userspace and makes readlink/readlinkat inconsistant with all other interfaces; and inconsistant with our stated return for these pathnames. As the readlinkat call does not have a flags parameter we cannot use the AT_EMPTY_PATH approach used in the other calls. Therefore expose whether the original path is infact entry via a new user_path_at_empty() path lookup function. Use this to determine whether to default to EINVAL or ENOENT for failures. Addresses http://bugs.launchpad.net/bugs/817187 [akpm@linux-foundation.org: remove unused getname_flags()] Signed-off-by: Andy Whitcroft <apw@canonical.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: <stable@kernel.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Christoph Hellwig <hch@lst.de>
* vfs: remove LOOKUP_NO_AUTOMOUNT flagLinus Torvalds2011-09-271-2/+0
| | | | | | | | | | | | | | | | | | | | | | That flag no longer makes sense, since we don't look up automount points as eagerly any more. Additionally, it turns out that the NO_AUTOMOUNT handling was buggy to begin with: it would avoid automounting even for cases where we really *needed* to do the automount handling, and could return ENOENT for autofs entries that hadn't been instantiated yet. With our new non-eager automount semantics, one discussion has been about adding a AT_AUTOMOUNT flag to vfs_fstatat (and thus the newfstatat() and fstatat64() system calls), but it's probably not worth it: you can always force at least directory automounting by simply adding the final '/' to the filename, which works for *all* of the stat family system calls, old and new. So AT_NO_AUTOMOUNT (and thus LOOKUP_NO_AUTOMOUNT) really were just a result of our bad default behavior. Acked-by: Ian Kent <raven@themaw.net> Acked-by: Trond Myklebust <Trond.Myklebust@netapp.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* vfs: optimize inode cache access patternsLinus Torvalds2011-08-061-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | The inode structure layout is largely random, and some of the vfs paths really do care. The path lookup in particular is already quite D$ intensive, and profiles show that accessing the 'inode->i_op->xyz' fields is quite costly. We already optimized the dcache to not unnecessarily load the d_op structure for members that are often NULL using the DCACHE_OP_xyz bits in dentry->d_flags, and this does something very similar for the inode ops that are used during pathname lookup. It also re-orders the fields so that the fields accessed by 'stat' are together at the beginning of the inode structure, and roughly in the order accessed. The effect of this seems to be in the 1-2% range for an empty kernel "make -j" run (which is fairly kernel-intensive, mostly in filename lookup), so it's visible. The numbers are fairly noisy, though, and likely depend a lot on exact microarchitecture. So there's more tuning to be done. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* readlinkat(), fchownat() and fstatat() with empty relative pathnamesAl Viro2011-03-151-2/+5
| | | | | | | | | For readlinkat() we simply allow empty pathname; it will fail unless we have dfd equal to O_PATH-opened symlink, so we are outside of POSIX scope here. For fchownat() and fstatat() we allow AT_EMPTY_PATH; let the caller explicitly ask for such behaviour. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* Add an AT_NO_AUTOMOUNT flag to suppress terminal automountDavid Howells2011-01-151-1/+3
| | | | | | | | | | | Add an AT_NO_AUTOMOUNT flag to suppress terminal automounting of automount point directories. This can be used by fstatat() users to permit the gathering of attributes on an automount point and also prevent mass-automounting of a directory of automount points by ls. Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Ian Kent <raven@themaw.net> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* Mark arguments to certain syscalls as being constDavid Howells2010-08-131-11/+18
| | | | | | | | | | | | | | | | Mark arguments to certain system calls as being const where they should be but aren't. The list includes: (*) The filename arguments of various stat syscalls, execve(), various utimes syscalls and some mount syscalls. (*) The filename arguments of some syscall helpers relating to the above. (*) The buffer argument of various write syscalls. Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: David S. Miller <davem@davemloft.net> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Add unlocked version of inode_add_bytes() functionDmitry Monakhov2009-12-231-2/+8
| | | | | | | | Quota code requires unlocked version of this function. Off course we can just copy-paste the code, but copy-pasting is always an evil. Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org> Signed-off-by: Jan Kara <jack@suse.cz>
* kill vfs_stat_fd / vfs_lstat_fdChristoph Hellwig2009-04-201-63/+42
| | | | | | | | | | There's really no reason to keep vfs_stat_fd and vfs_lstat_fd with Oleg's vfs_fstatat. Use vfs_fstatat for the few cases having the directory fd, and switch all others to vfs_stat / vfs_lstat. Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* Separate out common fstatat code into vfs_fstatatOleg Drokin2009-04-201-28/+28
| | | | | | | | | | This is a version incorporating Christoph's suggestion. Separate out common *fstatat functionality into a single function instead of duplicating it all over the code. Signed-off-by: Oleg Drokin <green@linuxhacker.ru> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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