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2016-05-18Merge branch 'work.iov_iter' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull iov_iter cleanups from Al Viro. * 'work.iov_iter' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: fold checks into iterate_and_advance() rw_verify_area(): saner calling conventions aio: remove a pointless assignment
2016-05-17Merge branch 'work.preadv2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs cleanups from Al Viro: "More cleanups from Christoph" * 'work.preadv2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: nfsd: use RWF_SYNC fs: add RWF_DSYNC aand RWF_SYNC ceph: use generic_write_sync fs: simplify the generic_write_sync prototype fs: add IOCB_SYNC and IOCB_DSYNC direct-io: remove the offset argument to dio_complete direct-io: eliminate the offset argument to ->direct_IO xfs: eliminate the pos variable in xfs_file_dio_aio_write filemap: remove the pos argument to generic_file_direct_write filemap: remove pos variables in generic_file_read_iter
2016-05-02give readdir(2)/getdents(2)/etc. uniform exclusion with lseek()Al Viro
same as read() on regular files has, and for the same reason. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-05-01fs: add RWF_DSYNC aand RWF_SYNCChristoph Hellwig
This is the per-I/O equivalent of O_DSYNC and O_SYNC, and very useful for all kinds of file servers and storage targets. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-04-03rw_verify_area(): saner calling conventionsAl Viro
Lift length capping into the few callers that care about it. Most of them treat all non-negatives as "success" and ignore the capped value, and with good reasons. Make rw_verify_area() return 0 on success. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-03-18Merge branches 'work.lookups', 'work.misc' and 'work.preadv2' into for-nextAl Viro
2016-03-04vfs: add the RWF_HIPRI flag for preadv2/pwritev2Christoph Hellwig
This adds a flag that tells the file system that this is a high priority request for which it's worth to poll the hardware. The flag is purely advisory and can be ignored if not supported. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Stephen Bates <stephen.bates@pmcs.com> Tested-by: Stephen Bates <stephen.bates@pmcs.com> Acked-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-03-04vfs: vfs: Define new syscalls preadv2,pwritev2Milosz Tanski
New syscalls that take an flag argument. No flags are added yet in this patch. Signed-off-by: Milosz Tanski <milosz@adfin.com> [hch: rebased on top of my kiocb changes] Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Stephen Bates <stephen.bates@pmcs.com> Tested-by: Stephen Bates <stephen.bates@pmcs.com> Acked-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-03-04vfs: pass a flags argument to vfs_readv/vfs_writevChristoph Hellwig
This way we can set kiocb flags also from the sync read/write path for the read_iter/write_iter operations. For now there is no way to pass flags to plain read/write operations as there is no real need for that, and all flags passed are explicitly rejected for these files. Signed-off-by: Milosz Tanski <milosz@adfin.com> [hch: rebased on top of my kiocb changes] Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Stephen Bates <stephen.bates@pmcs.com> Tested-by: Stephen Bates <stephen.bates@pmcs.com> Acked-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-02-28fs: return -EOPNOTSUPP if clone is not supportedChristoph Hellwig
-EBADF is a rather confusing error if an operations is not supported, and nfsd gets rather upset about it. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-02-20fs: allow no_seek_end_llseek to actually seekWouter van Kesteren
The user-visible impact of the issue is for example that without this patch sensors-detect breaks when trying to seek in /dev/cpu/0/cpuid. '~0ULL' is a 'unsigned long long' that when converted to a loff_t, which is signed, gets turned into -1. later in vfs_setpos we have 'if (offset > maxsize)', which makes it always return EINVAL. Fixes: b25472f9b961 ("new helpers: no_seek_end_llseek{,_size}()") Signed-off-by: Wouter van Kesteren <woutershep@gmail.com> Reviewed-by: Andreas Dilger <adilger@dilger.ca> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-01-23vfs: abort dedupe loop if fatal signals are pendingDarrick J. Wong
If the program running dedupe receives a fatal signal during the dedupe loop, we should bail out to avoid tying up the system. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-01-22wrappers for ->i_mutex accessAl Viro
parallel to mutex_{lock,unlock,trylock,is_locked,lock_nested}, inode_foo(inode) being mutex_foo(&inode->i_mutex). Please, use those for access to ->i_mutex; over the coming cycle ->i_mutex will become rwsem, with ->lookup() done with it held only shared. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-01-13Merge branch 'work.misc' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull misc vfs updates from Al Viro: "All kinds of stuff. That probably should've been 5 or 6 separate branches, but by the time I'd realized how large and mixed that bag had become it had been too close to -final to play with rebasing. Some fs/namei.c cleanups there, memdup_user_nul() introduction and switching open-coded instances, burying long-dead code, whack-a-mole of various kinds, several new helpers for ->llseek(), assorted cleanups and fixes from various people, etc. One piece probably deserves special mention - Neil's lookup_one_len_unlocked(). Similar to lookup_one_len(), but gets called without ->i_mutex and tries to avoid ever taking it. That, of course, means that it's not useful for any directory modifications, but things like getting inode attributes in nfds readdirplus are fine with that. I really should've asked for moratorium on lookup-related changes this cycle, but since I hadn't done that early enough... I *am* asking for that for the coming cycle, though - I'm going to try and get conversion of i_mutex to rwsem with ->lookup() done under lock taken shared. There will be a patch closer to the end of the window, along the lines of the one Linus had posted last May - mechanical conversion of ->i_mutex accesses to inode_lock()/inode_unlock()/inode_trylock()/ inode_is_locked()/inode_lock_nested(). To quote Linus back then: ----- | This is an automated patch using | | sed 's/mutex_lock(&\(.*\)->i_mutex)/inode_lock(\1)/' | sed 's/mutex_unlock(&\(.*\)->i_mutex)/inode_unlock(\1)/' | sed 's/mutex_lock_nested(&\(.*\)->i_mutex,[ ]*I_MUTEX_\([A-Z0-9_]*\))/inode_lock_nested(\1, I_MUTEX_\2)/' | sed 's/mutex_is_locked(&\(.*\)->i_mutex)/inode_is_locked(\1)/' | sed 's/mutex_trylock(&\(.*\)->i_mutex)/inode_trylock(\1)/' | | with a very few manual fixups ----- I'm going to send that once the ->i_mutex-affecting stuff in -next gets mostly merged (or when Linus says he's about to stop taking merges)" * 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (63 commits) nfsd: don't hold i_mutex over userspace upcalls fs:affs:Replace time_t with time64_t fs/9p: use fscache mutex rather than spinlock proc: add a reschedule point in proc_readfd_common() logfs: constify logfs_block_ops structures fcntl: allow to set O_DIRECT flag on pipe fs: __generic_file_splice_read retry lookup on AOP_TRUNCATED_PAGE fs: xattr: Use kvfree() [s390] page_to_phys() always returns a multiple of PAGE_SIZE nbd: use ->compat_ioctl() fs: use block_device name vsprintf helper lib/vsprintf: add %*pg format specifier fs: use gendisk->disk_name where possible poll: plug an unused argument to do_poll amdkfd: don't open-code memdup_user() cdrom: don't open-code memdup_user() rsxx: don't open-code memdup_user() mtip32xx: don't open-code memdup_user() [um] mconsole: don't open-code memdup_user_nul() [um] hostaudio: don't open-code memdup_user() ...
2016-01-01vfs: hoist the btrfs deduplication ioctl to the vfsDarrick J. Wong
Hoist the btrfs EXTENT_SAME ioctl up to the VFS and make the name more systematic (FIDEDUPERANGE). Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-01-01vfs: wire up compat ioctl for CLONE/CLONE_RANGEDarrick J. Wong
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-12-23new helpers: no_seek_end_llseek{,_size}()Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-12-08vfs: pull btrfs clone API to vfs layerChristoph Hellwig
The btrfs clone ioctls are now adopted by other file systems, with NFS and CIFS already having support for them, and XFS being under active development. To avoid growth of various slightly incompatible implementations, add one to the VFS. Note that clones are different from file copies in several ways: - they are atomic vs other writers - they support whole file clones - they support 64-bit legth clones - they do not allow partial success (aka short writes) - clones are expected to be a fast metadata operation Because of that it would be rather cumbersome to try to piggyback them on top of the recent clone_file_range infrastructure. The converse isn't true and the clone_file_range system call could try clone file range as a first attempt to copy, something that further patches will enable. Based on earlier work from Peng Tao. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-12-08locks: new locks_mandatory_area calling conventionChristoph Hellwig
Pass a loff_t end for the last byte instead of the 32-bit count parameter to allow full file clones even on 32-bit architectures. While we're at it also simplify the read/write selection. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: J. Bruce Fields <bfields@fieldses.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-12-01vfs: Add vfs_copy_file_range() support for pagecache copiesAnna Schumaker
This allows us to have an in-kernel copy mechanism that avoids frequent switches between kernel and user space. This is especially useful so NFSD can support server-side copies. The default (flags=0) means to first attempt copy acceleration, but use the pagecache if that fails. Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Padraig Brady <P@draigBrady.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-12-01vfs: add copy_file_range syscall and vfs helperZach Brown
Add a copy_file_range() system call for offloading copies between regular files. This gives an interface to underlying layers of the storage stack which can copy without reading and writing all the data. There are a few candidates that should support copy offloading in the nearer term: - btrfs shares extent references with its clone ioctl - NFS has patches to add a COPY command which copies on the server - SCSI has a family of XCOPY commands which copy in the device This system call avoids the complexity of also accelerating the creation of the destination file by operating on an existing destination file descriptor, not a path. Currently the high level vfs entry point limits copy offloading to files on the same mount and super (and not in the same file). This can be relaxed if we get implementations which can copy between file systems safely. Signed-off-by: Zach Brown <zab@redhat.com> [Anna Schumaker: Change -EINVAL to -EBADF during file verification, Change flags parameter from int to unsigned int, Add function to include/linux/syscalls.h, Check copy len after file open mode, Don't forbid ranges inside the same file, Use rw_verify_area() to veriy ranges, Use file_out rather than file_in, Add COPY_FR_REFLINK flag] Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-04-12new_sync_write(): discard ->ki_pos unless the return value is positiveAl Viro
That allows ->write_iter() instances much more convenient life wrt iocb->ki_pos (and fixes several filesystems with borderline POSIX violations when zero-length write succeeds and changes the current position). Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-04-12->aio_read and ->aio_write removedAl Viro
no remaining users Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-04-12kill do_sync_read/do_sync_writeAl Viro
all remaining instances of aio_{read,write} (all 4 of them) have explicit ->read and ->write resp.; do_sync_read/do_sync_write is never called by __vfs_read/__vfs_write anymore and no other users had been left. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-04-12make new_sync_{read,write}() staticAl Viro
All places outside of core VFS that checked ->read and ->write for being NULL or called the methods directly are gone now, so NULL {read,write} with non-NULL {read,write}_iter will do the right thing in all cases. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-04-12export __vfs_read()Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-04-12new helper: __vfs_write()Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-04-12switch {compat_,}do_readv_writev() to {compat_,}import_iovec()Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-04-12lift iov_iter into {compat_,}do_readv_writev()Al Viro
get it closer to matching {compat_,}rw_copy_check_uvector(). Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-03-26fs: move struct kiocb to fs.hChristoph Hellwig
struct kiocb now is a generic I/O container, so move it to fs.h. Also do a #include diet for aio.h while we're at it. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-03-13fs: don't allow to complete sync iocbs through aio_completeChristoph Hellwig
The AIO interface is fairly complex because it tries to allow filesystems to always work async and then wakeup a synchronous caller through aio_complete. It turns out that basically no one was doing this to avoid the complexity and context switches, and we've already fixed up the remaining users and can now get rid of this case. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-03-13fs: remove ki_nbytesChristoph Hellwig
There is no need to pass the total request length in the kiocb, as we already get passed in through the iov_iter argument. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-02-17Merge branch 'iov_iter' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull iov_iter updates from Al Viro: "More iov_iter work - missing counterpart of iov_iter_init() for bvec-backed ones and vfs_read_iter()/vfs_write_iter() - wrappers for sync calls of ->read_iter()/->write_iter()" * 'iov_iter' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: fs: add vfs_iter_{read,write} helpers new helper: iov_iter_bvec()
2015-01-29fs: add vfs_iter_{read,write} helpersChristoph Hellwig
Simple helpers that pass an arbitrary iov_iter to filesystems. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-01-16locks: convert posix locks to file_lock_contextJeff Layton
Signed-off-by: Jeff Layton <jlayton@primarydata.com> Acked-by: Christoph Hellwig <hch@lst.de>
2014-12-15Merge branch 'next' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security Pull security layer updates from James Morris: "In terms of changes, there's general maintenance to the Smack, SELinux, and integrity code. The IMA code adds a new kconfig option, IMA_APPRAISE_SIGNED_INIT, which allows IMA appraisal to require signatures. Support for reading keys from rootfs before init is call is also added" * 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (23 commits) selinux: Remove security_ops extern security: smack: fix out-of-bounds access in smk_parse_smack() VFS: refactor vfs_read() ima: require signature based appraisal integrity: provide a hook to load keys when rootfs is ready ima: load x509 certificate from the kernel integrity: provide a function to load x509 certificate from the kernel integrity: define a new function integrity_read_file() Security: smack: replace kzalloc with kmem_cache for inode_smack Smack: Lock mode for the floor and hat labels ima: added support for new kernel cmdline parameter ima_template_fmt ima: allocate field pointers array on demand in template_desc_init_fields() ima: don't allocate a copy of template_fmt in template_desc_init_fields() ima: display template format in meas. list if template name length is zero ima: added error messages to template-related functions ima: use atomic bit operations to protect policy update interface ima: ignore empty and with whitespaces policy lines ima: no need to allocate entry for comment ima: report policy load status ima: use path names cache ...
2014-11-18VFS: refactor vfs_read()Dmitry Kasatkin
integrity_kernel_read() duplicates the file read operations code in vfs_read(). This patch refactors vfs_read() code creating a helper function __vfs_read(). It is used by both vfs_read() and integrity_kernel_read(). Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-10-09cachefiles_write_page(): switch to __kernel_write()Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-05-06switch simple generic_file_aio_read() users to ->read_iter()Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-05-06new methods: ->read_iter() and ->write_iter()Al Viro
Beginning to introduce those. Just the callers for now, and it's clumsier than it'll eventually become; once we finish converting aio_read and aio_write instances, the things will get nicer. For now, these guys are in parallel to ->aio_read() and ->aio_write(); they take iocb and iov_iter, with everything in iov_iter already validated. File offset is passed in iocb->ki_pos, iov/nr_segs - in iov_iter. Main concerns in that series are stack footprint and ability to split the damn thing cleanly. [fix from Peter Ujfalusi <peter.ujfalusi@ti.com> folded] Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-05-06replace checking for ->read/->aio_read presence with check in ->f_modeAl Viro
Since we are about to introduce new methods (read_iter/write_iter), the tests in a bunch of places would have to grow inconveniently. Check once (at open() time) and store results in ->f_mode as FMODE_CAN_READ and FMODE_CAN_WRITE resp. It might end up being a temporary measure - once everything switches from ->aio_{read,write} to ->{read,write}_iter it might make sense to return to open-coded checks. We'll see... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-03-31Merge branch 'compat' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux Pull s390 compat wrapper rework from Heiko Carstens: "S390 compat system call wrapper simplification work. The intention of this work is to get rid of all hand written assembly compat system call wrappers on s390, which perform proper sign or zero extension, or pointer conversion of compat system call parameters. Instead all of this should be done with C code eg by using Al's COMPAT_SYSCALL_DEFINEx() macro. Therefore all common code and s390 specific compat system calls have been converted to the COMPAT_SYSCALL_DEFINEx() macro. In order to generate correct code all compat system calls may only have eg compat_ulong_t parameters, but no unsigned long parameters. Those patches which change parameter types from unsigned long to compat_ulong_t parameters are separate in this series, but shouldn't cause any harm. The only compat system calls which intentionally have 64 bit parameters (preadv64 and pwritev64) in support of the x86/32 ABI haven't been changed, but are now only available if an architecture defines __ARCH_WANT_COMPAT_SYS_PREADV64/PWRITEV64. System calls which do not have a compat variant but still need proper zero extension on s390, like eg "long sys_brk(unsigned long brk)" will get a proper wrapper function with the new s390 specific COMPAT_SYSCALL_WRAPx() macro: COMPAT_SYSCALL_WRAP1(brk, unsigned long, brk); which generates the following code (simplified): asmlinkage long sys_brk(unsigned long brk); asmlinkage long compat_sys_brk(long brk) { return sys_brk((u32)brk); } Given that the C file which contains all the COMPAT_SYSCALL_WRAP lines includes both linux/syscall.h and linux/compat.h, it will generate build errors, if the declaration of sys_brk() doesn't match, or if there exists a non-matching compat_sys_brk() declaration. In addition this will intentionally result in a link error if somewhere else a compat_sys_brk() function exists, which probably should have been used instead. Two more BUILD_BUG_ONs make sure the size and type of each compat syscall parameter can be handled correctly with the s390 specific macros. I converted the compat system calls step by step to verify the generated code is correct and matches the previous code. In fact it did not always match, however that was always a bug in the hand written asm code. In result we get less code, less bugs, and much more sanity checking" * 'compat' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (44 commits) s390/compat: add copyright statement compat: include linux/unistd.h within linux/compat.h s390/compat: get rid of compat wrapper assembly code s390/compat: build error for large compat syscall args mm/compat: convert to COMPAT_SYSCALL_DEFINE with changing parameter types kexec/compat: convert to COMPAT_SYSCALL_DEFINE with changing parameter types net/compat: convert to COMPAT_SYSCALL_DEFINE with changing parameter types ipc/compat: convert to COMPAT_SYSCALL_DEFINE with changing parameter types fs/compat: convert to COMPAT_SYSCALL_DEFINE with changing parameter types ipc/compat: convert to COMPAT_SYSCALL_DEFINE fs/compat: convert to COMPAT_SYSCALL_DEFINE security/compat: convert to COMPAT_SYSCALL_DEFINE mm/compat: convert to COMPAT_SYSCALL_DEFINE net/compat: convert to COMPAT_SYSCALL_DEFINE kernel/compat: convert to COMPAT_SYSCALL_DEFINE fs/compat: optional preadv64/pwrite64 compat system calls ipc/compat_sys_msgrcv: change msgtyp type from long to compat_long_t s390/compat: partial parameter conversion within syscall wrappers s390/compat: automatic zero, sign and pointer conversion of syscalls s390/compat: add sync_file_range and fallocate compat syscalls ...
2014-03-23vfs: atomic f_pos access in llseek()Eric Biggers
Commit 9c225f2655e36a4 ("vfs: atomic f_pos accesses as per POSIX") changed several system calls to use fdget_pos() instead of fdget(), but missed sys_llseek(). Fix it. Signed-off-by: Eric Biggers <ebiggers3@gmail.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-03-10get rid of fget_light()Al Viro
instead of returning the flags by reference, we can just have the low-level primitive return those in lower bits of unsigned long, with struct file * derived from the rest. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-03-10vfs: atomic f_pos accesses as per POSIXLinus Torvalds
Our write() system call has always been atomic in the sense that you get the expected thread-safe contiguous write, but we haven't actually guaranteed that concurrent writes are serialized wrt f_pos accesses, so threads (or processes) that share a file descriptor and use "write()" concurrently would quite likely overwrite each others data. This violates POSIX.1-2008/SUSv4 Section XSI 2.9.7 that says: "2.9.7 Thread Interactions with Regular File Operations All of the following functions shall be atomic with respect to each other in the effects specified in POSIX.1-2008 when they operate on regular files or symbolic links: [...]" and one of the effects is the file position update. This unprotected file position behavior is not new behavior, and nobody has ever cared. Until now. Yongzhi Pan reported unexpected behavior to Michael Kerrisk that was due to this. This resolves the issue with a f_pos-specific lock that is taken by read/write/lseek on file descriptors that may be shared across threads or processes. Reported-by: Yongzhi Pan <panyongzhi@gmail.com> Reported-by: Michael Kerrisk <mtk.manpages@gmail.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-03-06fs/compat: optional preadv64/pwrite64 compat system callsHeiko Carstens
The preadv64/pwrite64 have been implemented for the x32 ABI, in order to allow passing 64 bit arguments from user space without splitting them into two 32 bit parameters, like it would be necessary for usual compat tasks. Howevert these two system calls are only being used for the x32 ABI, so add __ARCH_WANT_COMPAT defines for these two compat syscalls and make these two only visible for x86. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2014-01-30fs/compat: fix parameter handling for compat readv/writev syscallsHeiko Carstens
We got a report that the pwritev syscall does not work correctly in compat mode on s390. It turned out that with commit 72ec35163f9f ("switch compat readv/writev variants to COMPAT_SYSCALL_DEFINE") we lost the zero extension of a couple of syscall parameters because the some parameter types haven't been converted from unsigned long to compat_ulong_t. This is needed for architectures where the ABI requires that the caller of a function performed zero and/or sign extension to 64 bit of all parameters. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Ingo Molnar <mingo@kernel.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Hendrik Brueckner <brueckner@linux.vnet.ibm.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: <stable@vger.kernel.org> [v3.10+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-22fs/read_write.c:compat_readv(): remove bogus area verifyCorey Minyard
The compat_do_readv_writev() function was doing a verify_area on the incoming iov, but the nr_segs value is not checked. If someone passes in a -1 for nr_segs, for instance, the function should return an EINVAL. However, it returns a EFAULT because the verify_area fails because it is checking an array of size MAX_UINT. The check is bogus, anyway, because the next check, compat_rw_copy_check_uvector(), will do all the necessary checking, anyway. The non-compat do_readv_writev() function doesn't do this check, so I think it's safe to just remove the code. Signed-off-by: Corey Minyard <cminyard@mvista.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-10-25file->f_op is never NULL...Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-07-30aio: Kill aio_rw_vect_retry()Kent Overstreet
This code doesn't serve any purpose anymore, since the aio retry infrastructure has been removed. This change should be safe because aio_read/write are also used for synchronous IO, and called from do_sync_read()/do_sync_write() - and there's no looping done in the sync case (the read and write syscalls). Signed-off-by: Kent Overstreet <koverstreet@google.com> Cc: Zach Brown <zab@redhat.com> Cc: Felipe Balbi <balbi@ti.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Jens Axboe <axboe@kernel.dk> Cc: Asai Thambi S P <asamymuthupa@micron.com> Cc: Selvan Mani <smani@micron.com> Cc: Sam Bradshaw <sbradshaw@micron.com> Cc: Jeff Moyer <jmoyer@redhat.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Benjamin LaHaise <bcrl@kvack.org> Signed-off-by: Benjamin LaHaise <bcrl@kvack.org>