summaryrefslogtreecommitdiffstats
path: root/fs/stat.c
Commit message (Collapse)AuthorAgeFilesLines
* fs: use type safe idmapping helpersChristian Brauner2022-10-261-2/+5
| | | | | | | | | | We already ported most parts and filesystems over for v6.0 to the new vfs{g,u}id_t type and associated helpers for v6.0. Convert the remaining places so we can remove all the old helpers. This is a non-functional change. Reviewed-by: Seth Forshee (DigitalOcean) <sforshee@kernel.org> Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
* vfs: support STATX_DIOALIGN on block devicesEric Biggers2022-09-111-0/+12
| | | | | | | | | | | | | | | Add support for STATX_DIOALIGN to block devices, so that direct I/O alignment restrictions are exposed to userspace in a generic way. Note that this breaks the tradition of stat operating only on the block device node, not the block device itself. However, it was felt that doing this is preferable, in order to make the interface useful and avoid needing separate interfaces for regular files and block devices. Signed-off-by: Eric Biggers <ebiggers@google.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Christian Brauner (Microsoft) <brauner@kernel.org> Link: https://lore.kernel.org/r/20220827065851.135710-3-ebiggers@kernel.org
* statx: add direct I/O alignment informationEric Biggers2022-09-111-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Traditionally, the conditions for when DIO (direct I/O) is supported were fairly simple. For both block devices and regular files, DIO had to be aligned to the logical block size of the block device. However, due to filesystem features that have been added over time (e.g. multi-device support, data journalling, inline data, encryption, verity, compression, checkpoint disabling, log-structured mode), the conditions for when DIO is allowed on a regular file have gotten increasingly complex. Whether a particular regular file supports DIO, and with what alignment, can depend on various file attributes and filesystem mount options, as well as which block device(s) the file's data is located on. Moreover, the general rule of DIO needing to be aligned to the block device's logical block size was recently relaxed to allow user buffers (but not file offsets) aligned to the DMA alignment instead. See commit bf8d08532bc1 ("iomap: add support for dma aligned direct-io"). XFS has an ioctl XFS_IOC_DIOINFO that exposes DIO alignment information. Uplifting this to the VFS is one possibility. However, as discussed (https://lore.kernel.org/linux-fsdevel/20220120071215.123274-1-ebiggers@kernel.org/T/#u), this ioctl is rarely used and not known to be used outside of XFS-specific code. It was also never intended to indicate when a file doesn't support DIO at all, nor was it intended for block devices. Therefore, let's expose this information via statx(). Add the STATX_DIOALIGN flag and two new statx fields associated with it: * stx_dio_mem_align: the alignment (in bytes) required for user memory buffers for DIO, or 0 if DIO is not supported on the file. * stx_dio_offset_align: the alignment (in bytes) required for file offsets and I/O segment lengths for DIO, or 0 if DIO is not supported on the file. This will only be nonzero if stx_dio_mem_align is nonzero, and vice versa. Note that as with other statx() extensions, if STATX_DIOALIGN isn't set in the returned statx struct, then these new fields won't be filled in. This will happen if the file is neither a regular file nor a block device, or if the file is a regular file and the filesystem doesn't support STATX_DIOALIGN. It might also happen if the caller didn't include STATX_DIOALIGN in the request mask, since statx() isn't required to return unrequested information. This commit only adds the VFS-level plumbing for STATX_DIOALIGN. For regular files, individual filesystems will still need to add code to support it. For block devices, a separate commit will wire it up too. Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Christian Brauner (Microsoft) <brauner@kernel.org> Signed-off-by: Eric Biggers <ebiggers@google.com> Link: https://lore.kernel.org/r/20220827065851.135710-2-ebiggers@kernel.org
* Merge tag 'riscv-for-linus-5.19-mw0' of ↵Linus Torvalds2022-05-311-1/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux Pull RISC-V updates from Palmer Dabbelt: - Support for the Svpbmt extension, which allows memory attributes to be encoded in pages - Support for the Allwinner D1's implementation of page-based memory attributes - Support for running rv32 binaries on rv64 systems, via the compat subsystem - Support for kexec_file() - Support for the new generic ticket-based spinlocks, which allows us to also move to qrwlock. These should have already gone in through the asm-geneic tree as well - A handful of cleanups and fixes, include some larger ones around atomics and XIP * tag 'riscv-for-linus-5.19-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (51 commits) RISC-V: Prepare dropping week attribute from arch_kexec_apply_relocations[_add] riscv: compat: Using seperated vdso_maps for compat_vdso_info RISC-V: Fix the XIP build RISC-V: Split out the XIP fixups into their own file RISC-V: ignore xipImage RISC-V: Avoid empty create_*_mapping definitions riscv: Don't output a bogus mmu-type on a no MMU kernel riscv: atomic: Add custom conditional atomic operation implementation riscv: atomic: Optimize dec_if_positive functions riscv: atomic: Cleanup unnecessary definition RISC-V: Load purgatory in kexec_file RISC-V: Add purgatory RISC-V: Support for kexec_file on panic RISC-V: Add kexec_file support RISC-V: use memcpy for kexec_file mode kexec_file: Fix kexec_file.c build error for riscv platform riscv: compat: Add COMPAT Kbuild skeletal support riscv: compat: ptrace: Add compat_arch_ptrace implement riscv: compat: signal: Add rt_frame implementation riscv: add memory-type errata for T-Head ...
| * fs: stat: compat: Add __ARCH_WANT_COMPAT_STATGuo Ren2022-04-261-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | RISC-V doesn't neeed compat_stat, so using __ARCH_WANT_COMPAT_STAT to exclude unnecessary SYSCALL functions. Signed-off-by: Guo Ren <guoren@linux.alibaba.com> Signed-off-by: Guo Ren <guoren@kernel.org> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Tested-by: Heiko Stuebner <heiko@sntech.de> Acked-by: Helge Deller <deller@gmx.de> # parisc Link: https://lore.kernel.org/r/20220405071314.3225832-6-guoren@kernel.org Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
* | stat: fix inconsistency between struct stat and struct compat_statMikulas Patocka2022-04-121-9/+10
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | struct stat (defined in arch/x86/include/uapi/asm/stat.h) has 32-bit st_dev and st_rdev; struct compat_stat (defined in arch/x86/include/asm/compat.h) has 16-bit st_dev and st_rdev followed by a 16-bit padding. This patch fixes struct compat_stat to match struct stat. [ Historical note: the old x86 'struct stat' did have that 16-bit field that the compat layer had kept around, but it was changes back in 2003 by "struct stat - support larger dev_t": https://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.git/commit/?id=e95b2065677fe32512a597a79db94b77b90c968d and back in those days, the x86_64 port was still new, and separate from the i386 code, and had already picked up the old version with a 16-bit st_dev field ] Note that we can't change compat_dev_t because it is used by compat_loop_info. Also, if the st_dev and st_rdev values are 32-bit, we don't have to use old_valid_dev to test if the value fits into them. This fixes -EOVERFLOW on filesystems that are on NVMe because NVMe uses the major number 259. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Cc: Andreas Schwab <schwab@linux-m68k.org> Cc: Matthew Wilcox <willy@infradead.org> Cc: Christoph Hellwig <hch@infradead.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* io-uring: Make statx API stableStefan Roesch2022-03-101-14/+35
| | | | | | | | | | | | | | | | | | | | | | | | | | One of the key architectual tenets is to keep the parameters for io-uring stable. After the call has been submitted, its value can be changed. Unfortunaltely this is not the case for the current statx implementation. IO-Uring change: This changes replaces the const char * filename pointer in the io_statx structure with a struct filename *. In addition it also creates the filename object during the prepare phase. With this change, the opcode also needs to invoke cleanup, so the filename object gets freed after processing the request. fs change: This replaces the const char* __user filename parameter in the two functions do_statx and vfs_statx with a struct filename *. In addition to be able to correctly construct a filename object a new helper function getname_statx_lookup_flags is introduced. The function makes sure that do_statx and vfs_statx is invoked with the correct lookup flags. Signed-off-by: Stefan Roesch <shr@fb.com> Link: https://lore.kernel.org/r/20220225185326.1373304-2-shr@fb.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
* fs: add generic helper for filling statx attribute flagsAmir Goldstein2021-08-171-0/+18
| | | | | | | | | | | | | | | The immutable and append-only properties on an inode are published on the inode's i_flags and enforced by the VFS. Create a helper to fill the corresponding STATX_ATTR_ flags in the kstat structure from the inode's i_flags. Only orange was converted to use this helper. Other filesystems could use it in the future. Suggested-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* fs: fix reporting supported extra file attributes for statx()Theodore Ts'o2021-04-171-0/+8
| | | | | | | | | | | | | | | | | statx(2) notes that any attribute that is not indicated as supported by stx_attributes_mask has no usable value. Commits 801e523796004 ("fs: move generic stat response attr handling to vfs_getattr_nosec") and 712b2698e4c02 ("fs/stat: Define DAX statx attribute") sets STATX_ATTR_AUTOMOUNT and STATX_ATTR_DAX, respectively, without setting stx_attributes_mask, which can cause xfstests generic/532 to fail. Fix this in the same way as commit 1b9598c8fb99 ("xfs: fix reporting supported extra file attributes for statx()") Fixes: 801e523796004 ("fs: move generic stat response attr handling to vfs_getattr_nosec") Fixes: 712b2698e4c02 ("fs/stat: Define DAX statx attribute") Cc: stable@kernel.org Signed-off-by: Theodore Ts'o <tytso@mit.edu>
* fs: make helpers idmap mount awareChristian Brauner2021-01-241-3/+5
| | | | | | | | | | | | | | | | | | | | | Extend some inode methods with an additional user namespace argument. A filesystem that is aware of idmapped mounts will receive the user namespace the mount has been marked with. This can be used for additional permission checking and also to enable filesystems to translate between uids and gids if they need to. We have implemented all relevant helpers in earlier patches. As requested we simply extend the exisiting inode method instead of introducing new ones. This is a little more code churn but it's mostly mechanical and doesnt't leave us with additional inode methods. Link: https://lore.kernel.org/r/20210121131959.646623-25-christian.brauner@ubuntu.com Cc: Christoph Hellwig <hch@lst.de> Cc: David Howells <dhowells@redhat.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: linux-fsdevel@vger.kernel.org Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
* stat: handle idmapped mountsChristian Brauner2021-01-241-6/+14
| | | | | | | | | | | | | | | | | | The generic_fillattr() helper fills in the basic attributes associated with an inode. Enable it to handle idmapped mounts. If the inode is accessed through an idmapped mount map it into the mount's user namespace before we store the uid and gid. If the initial user namespace is passed nothing changes so non-idmapped mounts will see identical behavior as before. Link: https://lore.kernel.org/r/20210121131959.646623-12-christian.brauner@ubuntu.com Cc: Christoph Hellwig <hch@lst.de> Cc: David Howells <dhowells@redhat.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: linux-fsdevel@vger.kernel.org Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: James Morris <jamorris@linux.microsoft.com> Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
* fs: remove KSTAT_QUERY_FLAGSChristoph Hellwig2020-09-261-4/+4
| | | | | | | | | KSTAT_QUERY_FLAGS expands to AT_STATX_SYNC_TYPE, which itself already is a mask. Remove the double name, especially given that the prefix is a little confusing vs the normal AT_* flags. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* fs: remove vfs_stat_set_lookup_flagsChristoph Hellwig2020-09-261-21/+12
| | | | | | | | | The function really obsfucates checking for valid flags and setting the lookup flags. The fact that it returns -EINVAL through and unsigned return value, which is then used as boolean really doesn't help either. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* fs: move vfs_fstatat out of lineChristoph Hellwig2020-09-261-2/+7
| | | | | | | | This allows to keep vfs_statx static in fs/stat.c to prepare for the following changes. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* fs: remove vfs_statx_fdChristoph Hellwig2020-09-261-15/+7
| | | | | | | | vfs_statx_fd is only used to implement vfs_fstat. Remove vfs_statx_fd and just implement vfs_fstat directly. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* Merge tag 'vfs-5.8-merge-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linuxLinus Torvalds2020-06-021-0/+3
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull DAX updates part one from Darrick Wong: "After many years of LKML-wrangling about how to enable programs to query and influence the file data access mode (DAX) when a filesystem resides on storage devices such as persistent memory, Ira Weiny has emerged with a proposed set of standard behaviors that has not been shot down by anyone! We're more or less standardizing on the current XFS behavior and adapting ext4 to do the same. This is the first of a handful pull requests that will make ext4 and XFS present a consistent interface for user programs that care about DAX. We add a statx attribute that programs can check to see if DAX is enabled on a particular file. Then, we update the DAX documentation to spell out the user-visible behaviors that filesystems will guarantee (until the next storage industry shakeup). The on-disk inode flag has been in XFS for a few years now. Summary: - Clean up io_is_direct. - Add a new statx flag to indicate when file data access is being done via DAX (as opposed to the page cache). - Update the documentation for how system administrators and application programmers can take advantage of the (still experimental DAX) feature" Link: https://lore.kernel.org/lkml/20200505002016.1085071-1-ira.weiny@intel.com/ * tag 'vfs-5.8-merge-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: Documentation/dax: Update Usage section fs/stat: Define DAX statx attribute fs: Remove unneeded IS_DAX() check in io_is_direct()
| * fs/stat: Define DAX statx attributeIra Weiny2020-05-041-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In order for users to determine if a file is currently operating in DAX state (effective DAX). Define a statx attribute value and set that attribute if the effective DAX flag is set. To go along with this we propose the following addition to the statx man page: STATX_ATTR_DAX The file is in the DAX (cpu direct access) state. DAX state attempts to minimize software cache effects for both I/O and memory mappings of this file. It requires a file system which has been configured to support DAX. DAX generally assumes all accesses are via cpu load / store instructions which can minimize overhead for small accesses, but may adversely affect cpu utilization for large transfers. File I/O is done directly to/from user-space buffers and memory mapped I/O may be performed with direct memory mappings that bypass kernel page cache. While the DAX property tends to result in data being transferred synchronously, it does not give the same guarantees of O_SYNC where data and the necessary metadata are transferred together. A DAX file may support being mapped with the MAP_SYNC flag, which enables a program to use CPU cache flush instructions to persist CPU store operations without an explicit fsync(2). See mmap(2) for more information. Reviewed-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Ira Weiny <ira.weiny@intel.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
* | Merge tag 'for-5.8/io_uring-2020-06-01' of git://git.kernel.dk/linux-blockLinus Torvalds2020-06-021-15/+22
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull io_uring updates from Jens Axboe: "A relatively quiet round, mostly just fixes and code improvements. In particular: - Make statx just use the generic statx handler, instead of open coding it. We don't need that anymore, as we always call it async safe (Bijan) - Enable closing of the ring itself. Also fixes O_PATH closure (me) - Properly name completion members (me) - Batch reap of dead file registrations (me) - Allow IORING_OP_POLL with double waitqueues (me) - Add tee(2) support (Pavel) - Remove double off read (Pavel) - Fix overflow cancellations (Pavel) - Improve CQ timeouts (Pavel) - Async defer drain fixes (Pavel) - Add support for enabling/disabling notifications on a registered eventfd (Stefano) - Remove dead state parameter (Xiaoguang) - Disable SQPOLL submit on dying ctx (Xiaoguang) - Various code cleanups" * tag 'for-5.8/io_uring-2020-06-01' of git://git.kernel.dk/linux-block: (29 commits) io_uring: fix overflowed reqs cancellation io_uring: off timeouts based only on completions io_uring: move timeouts flushing to a helper statx: hide interfaces no longer used by io_uring io_uring: call statx directly statx: allow system call to be invoked from io_uring io_uring: add io_statx structure io_uring: get rid of manual punting in io_close io_uring: separate DRAIN flushing into a cold path io_uring: don't re-read sqe->off in timeout_prep() io_uring: simplify io_timeout locking io_uring: fix flush req->refs underflow io_uring: don't submit sqes when ctx->refs is dying io_uring: async task poll trigger cleanup io_uring: add tee(2) support splice: export do_tee() io_uring: don't repeat valid flag list io_uring: rename io_file_put() io_uring: remove req->needs_fixed_files io_uring: cleanup io_poll_remove_one() logic ...
| * | statx: hide interfaces no longer used by io_uringBijan Mottahedeh2020-05-261-2/+3
| | | | | | | | | | | | | | | | | | | | | | | | The io_uring interfaces have been replaced by do_statx() and are no longer needed. Signed-off-by: Bijan Mottahedeh <bijan.mottahedeh@oracle.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | statx: allow system call to be invoked from io_uringBijan Mottahedeh2020-05-261-13/+19
| |/ | | | | | | | | | | | | This is a prepatory patch to allow io_uring to invoke statx directly. Signed-off-by: Bijan Mottahedeh <bijan.mottahedeh@oracle.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
* | statx: add mount_rootMiklos Szeredi2020-05-141-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Determining whether a path or file descriptor refers to a mountpoint (or more precisely a mount root) is not trivial using current tools. Add a flag to statx that indicates whether the path or fd refers to the root of a mount or not. Cc: linux-api@vger.kernel.org Cc: linux-man@vger.kernel.org Reported-by: Lennart Poettering <mzxreary@0pointer.de> Reported-by: J. Bruce Fields <bfields@fieldses.org> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
* | statx: add mount IDMiklos Szeredi2020-05-141-0/+4
| | | | | | | | | | | | | | | | | | Systemd is hacking around to get it and it's trivial to add to statx, so... Cc: linux-api@vger.kernel.org Cc: linux-man@vger.kernel.org Signed-off-by: Miklos Szeredi <mszeredi@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
* | statx: don't clear STATX_ATIME on SB_RDONLYMiklos Szeredi2020-05-141-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | IS_NOATIME(inode) is defined as __IS_FLG(inode, SB_RDONLY|SB_NOATIME), so generic_fillattr() will clear STATX_ATIME from the result_mask if the super block is marked read only. This was probably not the intention, so fix to only clear STATX_ATIME if the fs doesn't support atime at all. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com> Acked-by: David Howells <dhowells@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
* | uapi: deprecate STATX_ALLMiklos Szeredi2020-05-141-1/+0
|/ | | | | | | | | | | | | | | | | | | Constants of the *_ALL type can be actively harmful due to the fact that developers will usually fail to consider the possible effects of future changes to the definition. Deprecate STATX_ALL in the uapi, while no damage has been done yet. We could keep something like this around in the kernel, but there's actually no point, since all filesystems should be explicitly checking flags that they support and not rely on the VFS masking unknown ones out: a flag could be known to the VFS, yet not known to the filesystem. Cc: David Howells <dhowells@redhat.com> Cc: linux-api@vger.kernel.org Cc: linux-man@vger.kernel.org Signed-off-by: Miklos Szeredi <mszeredi@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
* fs: make two stat prep helpers availableJens Axboe2020-01-201-12/+22
| | | | | | | | To implement an async stat, we need to provide the flags mapping and the statx user copy. Make them available internally, through fs/internal.h. Signed-off-by: Jens Axboe <axboe@kernel.dk>
* fs: move generic stat response attr handling to vfs_getattr_nosecChristoph Hellwig2019-02-011-5/+7
| | | | | | | | | | | | generic_fillattr is an optional helper that isn't used by all file systems, move handling purely based on inode flags to vfs_getattr_nosec, which is common code. This fixes setting this flag for file systems not using generic_fillattr like xfs. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* y2038: Remove newstat family from default syscall setArnd Bergmann2018-08-291-0/+3
| | | | | | | | | | | | | | | | | | | | | | We have four generations of stat() syscalls: - the oldstat syscalls that are only used on the older architectures - the newstat family that is used on all 64-bit architectures but lacked support for large files on 32-bit architectures. - the stat64 family that is used mostly on 32-bit architectures to replace newstat - statx() to replace all of the above, adding 64-bit timestamps among other things. We already compile stat64 only on those architectures that need it, but newstat is always built, including on those that don't reference it. This adds a new __ARCH_WANT_NEW_STAT symbol along the lines of __ARCH_WANT_OLD_STAT and __ARCH_WANT_STAT64 to control compilation of newstat. All architectures that need it use an explict define, the others now get a little bit smaller, and future architecture (including 64-bit targets) won't ever see it. Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
* fs: add do_readlinkat() helper; remove internal call to sys_readlinkat()Dominik Brodowski2018-04-021-3/+9
| | | | | | | | | | | | Using the do_readlinkat() helper removes an in-kernel call to the sys_readlinkat() syscall. This patch is part of a series which removes in-kernel calls to syscalls. On this basis, the syscall entry path can be streamlined. For details, see http://lkml.kernel.org/r/20180325162527.GA17492@light.dominikbrodowski.net Cc: Alexander Viro <viro@zeniv.linux.org.uk> Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
* License cleanup: add SPDX GPL-2.0 license identifier to files with no licenseGreg Kroah-Hartman2017-11-021-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* 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>
generated by cgit v1.2.3 (git 2.25.1) at 2024-10-31 08:38:24 +0000