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* VFS: normal filesystems (and lustre): d_inode() annotationsDavid Howells2015-04-15
| | | | | | | that's the bulk of filesystem drivers dealing with inodes of their own Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* make new_sync_{read,write}() staticAl Viro2015-04-11
| | | | | | | | 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>
* fs: remove mapping->backing_dev_infoChristoph Hellwig2015-01-20
| | | | | | | | | | | Now that we never use the backing_dev_info pointer in struct address_space we can simply remove it and save 4 to 8 bytes in every inode. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Reviewed-by: Tejun Heo <tj@kernel.org> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Jens Axboe <axboe@fb.com>
* fs: introduce f_op->mmap_capabilities for nommu mmap supportChristoph Hellwig2015-01-20
| | | | | | | | | | | | | | | | | | | Since "BDI: Provide backing device capability information [try #3]" the backing_dev_info structure also provides flags for the kind of mmap operation available in a nommu environment, which is entirely unrelated to it's original purpose. Introduce a new nommu-only file operation to provide this information to the nommu mmap code instead. Splitting this from the backing_dev_info structure allows to remove lots of backing_dev_info instance that aren't otherwise needed, and entirely gets rid of the concept of providing a backing_dev_info for a character device. It also removes the need for the mtd_inodefs filesystem. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Tejun Heo <tj@kernel.org> Acked-by: Brian Norris <computersforpeace@gmail.com> Signed-off-by: Jens Axboe <axboe@fb.com>
* fs/ramfs/file-nommu.c: replace count*size kzalloc by kcallocFabian Frederick2014-08-08
| | | | | | | Signed-off-by: Fabian Frederick <fabf@skynet.be> Cc: Axel Lin <axel.lin@ingics.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* ->splice_write() via ->write_iter()Al Viro2014-06-12
| | | | | | | | | | iter_file_splice_write() - a ->splice_write() instance that gathers the pipe buffers, builds a bio_vec-based iov_iter covering those and feeds it to ->write_iter(). A bunch of simple cases coverted to that... [AV: fixed the braino spotted by Cyrill] Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* write_iter variants of {__,}generic_file_aio_write()Al Viro2014-05-06
| | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* switch simple generic_file_aio_read() users to ->read_iter()Al Viro2014-05-06
| | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* fs/ramfs: move ramfs_aops to inode.cAxel Lin2014-01-23
| | | | | | | | | | ramfs_aops is identical in file-mmu.c and file-nommu.c. Thus move it to fs/ramfs/inode.c and make it static. Signed-off-by: Axel Lin <axel.lin@ingics.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/ramfs/file-nommu.c: make ramfs_nommu_get_unmapped_area() and ↵Axel Lin2014-01-23
| | | | | | | | | | | | | ramfs_nommu_mmap() static Since commit 853ac43ab194 ("shmem: unify regular and tiny shmem"), ramfs_nommu_get_unmapped_area() and ramfs_nommu_mmap() are not directly referenced outside of file-nommu.c. Thus make them static. Signed-off-by: Axel Lin <axel.lin@ingics.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/ramfs: don't use module_init for non-modular core codePaul Gortmaker2014-01-21
| | | | | | | | | | | | | | | | | | | | | | | The ramfs is always built in. It will never be modular, so using module_init as an alias for __initcall is rather misleading. Fix this up now, so that we can relocate module_init from init.h into module.h in the future. If we don't do this, we'd have to add module.h to obviously non-modular code, and that would be a worse thing. Note that direct use of __initcall is discouraged, vs. one of the priority categorized subgroups. As __initcall gets mapped onto device_initcall, our use of fs_initcall (which makes sense for fs code) will thus change this registration from level 6-device to level 5-fs (i.e. slightly earlier). However no observable impact of that small difference has been observed during testing, or is expected. Also note that this change uncovers a missing semicolon bug in the registration of the initcall. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* initmpfs: move rootfs code from fs/ramfs/ to init/Rob Landley2013-09-11
| | | | | | | | | | | | | | | | | | | | | | | When the rootfs code was a wrapper around ramfs, having them in the same file made sense. Now that it can wrap another filesystem type, move it in with the init code instead. This also allows a subsequent patch to access rootfstype= command line arg. Signed-off-by: Rob Landley <rob@landley.net> Cc: Jeff Layton <jlayton@redhat.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Stephen Warren <swarren@nvidia.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Jim Cromie <jim.cromie@gmail.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* initmpfs: move bdi setup from init_rootfs to init_ramfsRob Landley2013-09-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Even though ramfs hasn't got a backing device, commit e0bf68ddec4f ("mm: bdi init hooks") added one anyway, and put the initialization in init_rootfs() since that's the first user, leaving it out of init_ramfs() to avoid duplication. But initmpfs uses init_tmpfs() instead, so move the init into the filesystem's init function, add a "once" guard to prevent duplicate initialization, and call the filesystem init from rootfs init. This goes part of the way to allowing ramfs to be built as a module. [akpm@linux-foundation.org; using bit 1 was odd] Signed-off-by: Rob Landley <rob@landley.net> Cc: Jeff Layton <jlayton@redhat.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Stephen Warren <swarren@nvidia.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Jim Cromie <jim.cromie@gmail.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* initmpfs: replace MS_NOUSER in initramfsRob Landley2013-09-11
| | | | | | | | | | | | | | | | | | | Mounting MS_NOUSER prevents --bind mounts from rootfs. Prevent new rootfs mounts with a different mechanism that doesn't affect bind mounts. Signed-off-by: Rob Landley <rob@landley.net> Cc: Jeff Layton <jlayton@redhat.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Stephen Warren <swarren@nvidia.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Jim Cromie <jim.cromie@gmail.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge branch 'for-linus' of ↵Linus Torvalds2013-02-26
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs pile (part one) from Al Viro: "Assorted stuff - cleaning namei.c up a bit, fixing ->d_name/->d_parent locking violations, etc. The most visible changes here are death of FS_REVAL_DOT (replaced with "has ->d_weak_revalidate()") and a new helper getting from struct file to inode. Some bits of preparation to xattr method interface changes. Misc patches by various people sent this cycle *and* ocfs2 fixes from several cycles ago that should've been upstream right then. PS: the next vfs pile will be xattr stuff." * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (46 commits) saner proc_get_inode() calling conventions proc: avoid extra pde_put() in proc_fill_super() fs: change return values from -EACCES to -EPERM fs/exec.c: make bprm_mm_init() static ocfs2/dlm: use GFP_ATOMIC inside a spin_lock ocfs2: fix possible use-after-free with AIO ocfs2: Fix oops in ocfs2_fast_symlink_readpage() code path get_empty_filp()/alloc_file() leave both ->f_pos and ->f_version zero target: writev() on single-element vector is pointless export kernel_write(), convert open-coded instances fs: encode_fh: return FILEID_INVALID if invalid fid_type kill f_vfsmnt vfs: kill FS_REVAL_DOT by adding a d_weak_revalidate dentry op nfsd: handle vfs_getattr errors in acl protocol switch vfs_getattr() to struct path default SET_PERSONALITY() in linux/elf.h ceph: prepopulate inodes only when request is aborted d_hash_and_lookup(): export, switch open-coded instances 9p: switch v9fs_set_create_acl() to inode+fid, do it before d_instantiate() 9p: split dropping the acls from v9fs_set_create_acl() ...
| * new helper: file_inode(file)Al Viro2013-02-22
| | | | | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | userns: Allow the userns root to mount ramfs.Eric W. Biederman2013-01-27
|/ | | | | | | | | | | | | | There is no backing store to ramfs and file creation rules are the same as for any other filesystem so it is semantically safe to allow unprivileged users to mount it. The memory control group successfully limits how much memory ramfs can consume on any system that cares about a user namespace root using ramfs to exhaust memory the memory control group can be deployed. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
* don't pass nameidata to ->create()Al Viro2012-07-14
| | | | | | | | boolean "does it have to be exclusive?" flag is passed instead; Local filesystem should just ignore it - the object is guaranteed not to be there yet. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* fs: ramfs: file-nommu: add SetPageUptodate()Bob Liu2012-07-11
| | | | | | | | | | | | | | | | | | | | | | | | | | There is a bug in the below scenario for !CONFIG_MMU: 1. create a new file 2. mmap the file and write to it 3. read the file can't get the correct value Because sys_read() -> generic_file_aio_read() -> simple_readpage() -> clear_page() which causes the page to be zeroed. Add SetPageUptodate() to ramfs_nommu_expand_for_mapping() so that generic_file_aio_read() do not call simple_readpage(). Signed-off-by: Bob Liu <lliubbo@gmail.com> Cc: Hugh Dickins <hughd@google.com> Cc: David Howells <dhowells@redhat.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Greg Ungerer <gerg@uclinux.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* tidy up after d_make_root() conversionAl Viro2012-03-20
| | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* switch open-coded instances of d_make_root() to new helperAl Viro2012-03-20
| | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* pohmelfs: propagate umode_tAl Viro2012-01-03
| | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* switch ->mknod() to umode_tAl Viro2012-01-03
| | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* switch ->create() to umode_tAl Viro2012-01-03
| | | | | | | | vfs_create() ignores everything outside of 16bit subset of its mode argument; switching it to umode_t is obviously equivalent and it's the only caller of the method Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* switch vfs_mkdir() and ->mkdir() to umode_tAl Viro2012-01-03
| | | | | | | vfs_mkdir() gets int, but immediately drops everything that might not fit into umode_t and that's the only caller of ->mkdir()... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* ramfs: remove module leftoversRichard Weinberger2011-11-02
| | | | | | | | | | | Since ramfs is hard-selected to "y", the module leftovers make no sense. Signed-off-by: Richard Weinberger <richard@nod.at> Reviewed-by: WANG Cong <xiyou.wangcong@gmail.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* ramfs: fix memleak on no-mmu archBob Liu2011-04-14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On no-mmu arch, there is a memleak during shmem test. The cause of this memleak is ramfs_nommu_expand_for_mapping() added page refcount to 2 which makes iput() can't free that pages. The simple test file is like this: int main(void) { int i; key_t k = ftok("/etc", 42); for ( i=0; i<100; ++i) { int id = shmget(k, 10000, 0644|IPC_CREAT); if (id == -1) { printf("shmget error\n"); } if(shmctl(id, IPC_RMID, NULL ) == -1) { printf("shm rm error\n"); return -1; } } printf("run ok...\n"); return 0; } And the result: root:/> free total used free shared buffers Mem: 60320 17912 42408 0 0 -/+ buffers: 17912 42408 root:/> shmem run ok... root:/> free total used free shared buffers Mem: 60320 19096 41224 0 0 -/+ buffers: 19096 41224 root:/> shmem run ok... root:/> free total used free shared buffers Mem: 60320 20296 40024 0 0 -/+ buffers: 20296 40024 ... After this patch the test result is:(no memleak anymore) root:/> free total used free shared buffers Mem: 60320 16668 43652 0 0 -/+ buffers: 16668 43652 root:/> shmem run ok... root:/> free total used free shared buffers Mem: 60320 16668 43652 0 0 -/+ buffers: 16668 43652 Signed-off-by: Bob Liu <lliubbo@gmail.com> Acked-by: Hugh Dickins <hughd@google.com> Signed-off-by: David Howells <dhowells@redhat.com> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* convert get_sb_nodev() usersAl Viro2010-10-29
| | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* fs: do not assign default i_ino in new_inodeChristoph Hellwig2010-10-25
| | | | | | | | | | | | | | | Instead of always assigning an increasing inode number in new_inode move the call to assign it into those callers that actually need it. For now callers that need it is estimated conservatively, that is the call is added to all filesystems that do not assign an i_ino by themselves. For a few more filesystems we can avoid assigning any inode number given that they aren't user visible, and for others it could be done lazily when an inode number is actually needed, but that's left for later patches. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* check ATTR_SIZE contraints in inode_change_okChristoph Hellwig2010-08-09
| | | | | | | | | | | | | | | | | | | | | Make sure we check the truncate constraints early on in ->setattr by adding those checks to inode_change_ok. Also clean up and document inode_change_ok to make this obvious. As a fallout we don't have to call inode_newsize_ok from simple_setsize and simplify it down to a truncate_setsize which doesn't return an error. This simplifies a lot of setattr implementations and means we use truncate_setsize almost everywhere. Get rid of fat_setsize now that it's trivial and mark ext2_setsize static to make the calling convention obvious. Keep the inode_newsize_ok in vmtruncate for now as all callers need an audit for its removal anyway. Note: setattr code in ecryptfs doesn't call inode_change_ok at all and needs a deeper audit, but that is left for later. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* rename generic_setattrChristoph Hellwig2010-08-09
| | | | | | | | | Despite its name it's now a generic implementation of ->setattr, but rather a helper to copy attributes from a struct iattr to the inode. Rename it to setattr_copy to reflect this fact. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* fs: convert simple fs to new truncateNick Piggin2010-05-27
| | | | | | | | | Convert simple filesystems: ramfs, configfs, sysfs, block_dev to new truncate sequence. Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* rename the generic fsync implementationsChristoph Hellwig2010-05-27
| | | | | | | | | | | | | | | | We don't name our generic fsync implementations very well currently. The no-op implementation for in-memory filesystems currently is called simple_sync_file which doesn't make too much sense to start with, the the generic one for simple filesystems is called simple_fsync which can lead to some confusion. This patch renames the generic file fsync method to generic_file_fsync to match the other generic_file_* routines it is supposed to be used with, and the no-op implementation to noop_fsync to make it obvious what to expect. In addition add some documentation for both methods. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* ramfs: replace inode uid,gid,mode initialization with helper functionDmitry Monakhov2010-05-21
| | | | | | | | | - seems what ramfs_get_inode is only locally, make it static. [AV: the hell it is; it's used by shmem, so shmem needed conversion too and no, that function can't be made static] Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* devtmpfs: support !CONFIG_TMPFSPeter Korsgaard2010-05-21
| | | | | | | | | | | | Make devtmpfs available on (embedded) configurations without SHMEM/TMPFS, using ramfs instead. Saves ~15KB. Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk> Acked-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* include cleanup: Update gfp.h and slab.h includes to prepare for breaking ↵Tejun Heo2010-03-30
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
* nommu: fix shared mmap after truncate shrinkage problemsDavid Howells2010-01-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix a problem in NOMMU mmap with ramfs whereby a shared mmap can happen over the end of a truncation. The problem is that ramfs_nommu_check_mappings() checks that the reduced file size against the VMA tree, but not the vm_region tree. The following sequence of events can cause the problem: fd = open("/tmp/x", O_RDWR|O_TRUNC|O_CREAT, 0600); ftruncate(fd, 32 * 1024); a = mmap(NULL, 32 * 1024, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0); b = mmap(NULL, 16 * 1024, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0); munmap(a, 32 * 1024); ftruncate(fd, 16 * 1024); c = mmap(NULL, 32 * 1024, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0); Mapping 'a' creates a vm_region covering 32KB of the file. Mapping 'b' sees that the vm_region from 'a' is covering the region it wants and so shares it, pinning it in memory. Mapping 'a' then goes away and the file is truncated to the end of VMA 'b'. However, the region allocated by 'a' is still in effect, and has _not_ been reduced. Mapping 'c' is then created, and because there's a vm_region covering the desired region, get_unmapped_area() is _not_ called to repeat the check, and the mapping is granted, even though the pages from the latter half of the mapping have been discarded. However: d = mmap(NULL, 16 * 1024, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0); Mapping 'd' should work, and should end up sharing the region allocated by 'a'. To deal with this, we shrink the vm_region struct during the truncation, lest do_mmap_pgoff() take it as licence to share the full region automatically without calling the get_unmapped_area() file op again. Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Al Viro <viro@zeniv.linux.org.uk> Cc: Greg Ungerer <gerg@snapgear.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* nommu: fix race between ramfs truncation and shared mmapDavid Howells2010-01-16
| | | | | | | | | | | | | | | | | | | | | | | Fix the race between the truncation of a ramfs file and an attempt to make a shared mmap of region of that file. The problem is that do_mmap_pgoff() calls f_op->get_unmapped_area() to verify that the file region is made of contiguous pages and to find its base address - but there isn't any locking to guarantee this region until vma_prio_tree_insert() is called by add_vma_to_mm(). Note that moving the functionality into f_op->mmap() doesn't help as that is also called before vma_prio_tree_insert(). Instead make ramfs_nommu_check_mappings() grab nommu_region_sem whilst it does its checks. This means that this function will wait whilst mmaps take place. Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Al Viro <viro@zeniv.linux.org.uk> Cc: Greg Ungerer <gerg@snapgear.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* nommu: ramfs: remove unused local varMike Frysinger2009-12-17
| | | | | | | | Signed-off-by: Mike Frysinger <vapier@gentoo.org> Cc: David Howells <dhowells@redhat.com> Acked-by: Greg Ungerer <gerg@snapgear.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* truncate: use new helpersnpiggin@suse.de2009-09-24
| | | | | | | | | | | | | | | Update some fs code to make use of new helper functions introduced in the previous patch. Should be no significant change in behaviour (except CIFS now calls send_sig under i_lock, via inode_newsize_ok). Reviewed-by: Christoph Hellwig <hch@lst.de> Acked-by: Miklos Szeredi <miklos@szeredi.hu> Cc: linux-nfs@vger.kernel.org Cc: Trond.Myklebust@netapp.com Cc: linux-cifs-client@lists.samba.org Cc: sfrench@samba.org Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* ramfs: move RAMFS_MAGIC to include/linux/magic.hmaximilian attems2009-09-23
| | | | | | | | | initramfs userspace likes to use this magic number. Cc: Hugh Dickins <hugh.dickins@tiscali.co.uk> Signed-off-by: maximilian attems <max@stro.at> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* writeback: add name to backing_dev_infoJens Axboe2009-09-11
| | | | | | | | This enables us to track who does what and print info. Its main use is catching dirty inodes on the default_backing_dev_info, so we can fix that up. Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* fs/ramfs/file-nommu.c needs include/linux/sched.hCatalin Marinas2009-07-29
| | | | | | | | | | | | This file makes use of various macros defined in files like asm/current.h or asm-generic/resource.h. All these files can be included via sched.h. The building of the !MMU ARM kernel (with additional patches) fails without this change. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: David Howells <dhowells@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* ramfs: ignore unknown mount optionsMike Frysinger2009-06-14
| | | | | | | | | | | | | | | | | | | | | | | | | On systems where CONFIG_SHMEM is disabled, mounting tmpfs filesystems can fail when tmpfs options are used. This is because tmpfs creates a small wrapper around ramfs which rejects unknown options, and ramfs itself only supports a tiny subset of what tmpfs supports. This makes it pretty hard to use the same userspace systems across different configuration systems. As such, ramfs should ignore the tmpfs options when tmpfs is merely a wrapper around ramfs. This used to work before commit c3b1b1cbf0 as previously, ramfs would ignore all options. But now, we get: ramfs: bad mount option: size=10M mount: mounting mdev on /dev failed: Invalid argument Another option might be to restore the previous behavior, where ramfs simply ignored all unknown mount options ... which is what Hugh prefers. Signed-off-by: Mike Frysinger <vapier@gentoo.org> Signed-off-by: Hugh Dickins <hugh.dickins@tiscali.co.uk> Acked-by: Matt Mackall <mpm@selenic.com> Acked-by: Wu Fengguang <fengguang.wu@intel.com> Cc: stable@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* ramfs: fix double freeing s_fs_info on failed mountIngo Molnar2009-04-07
| | | | | | | | | | | | If ramfs mount fails, s_fs_info will be freed twice in ramfs_fill_super() and ramfs_kill_sb(), leading to kernel oops. Consolidate and beautify the code. Make sure s_fs_info and s_root are in known good states. Acked-by: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* ramfs: add support for "mode=" mount optionWu Fengguang2009-04-01
| | | | | | | | | | | | | Addresses http://bugzilla.kernel.org/show_bug.cgi?id=12843 "I use ramfs instead of tmpfs for /tmp because I don't use swap on my laptop. Some apps need 1777 mode for /tmp directory, but ramfs does not support 'mode=' mount option." Reported-by: Avan Anishchuk <matimatik@gmail.com> Signed-off-by: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* ramfs-nommu: use generic lru cacheJohannes Weiner2009-04-01
| | | | | | | | | | | | | | | | | | | | | Instead of open-coding the lru-list-add pagevec batching when expanding a file mapping from zero, defer to the appropriate page cache function that also takes care of adding the page to the lru list. This is cleaner, saves code and reduces the stack footprint by 16 words worth of pagevec. Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: David Howells <dhowells@redhat.com> Cc: Nick Piggin <npiggin@suse.de> Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Rik van Riel <riel@redhat.com> Cc: Peter Zijlstra <peterz@infradead.com> Cc: MinChan Kim <minchan.kim@gmail.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com> Cc: Greg Ungerer <gerg@snapgear.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* ramfs: Remove quota callJan Kara2009-03-25
| | | | | | Ramfs has no bussiness in quotas. Signed-off-by: Jan Kara <jack@suse.cz>
* nommu: ramfs: don't leak pages when adding to page cache failsJohannes Weiner2009-03-14
| | | | | | | | | | | | | | | | | | When a ramfs nommu mapping is expanded, contiguous pages are allocated and added to the pagecache. The caller's reference is then passed on by moving whole pagevecs to the file lru list. If the page cache adding fails, make sure that the error path also moves the pagevec contents which might still contain up to PAGEVEC_SIZE successfully added pages, of which we would leak references otherwise. Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Cc: David Howells <dhowells@redhat.com> Cc: Enrik Berkhan <Enrik.Berkhan@ge.com> Cc: Nick Piggin <nickpiggin@yahoo.com.au> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* nommu: ramfs: pages allocated to an inode's pagecache may get wrongly discardedEnrik Berkhan2009-03-14
| | | | | | | | | | | | | | | | | | | | | | | | | | The pages attached to a ramfs inode's pagecache by truncation from nothing - as done by SYSV SHM for example - may get discarded under memory pressure. The problem is that the pages are not marked dirty. Anything that creates data in an MMU-based ramfs will cause the pages holding that data will cause the set_page_dirty() aop to be called. For the NOMMU-based mmap, set_page_dirty() may be called by write(), but it won't be called by page-writing faults on writable mmaps, and it isn't called by ramfs_nommu_expand_for_mapping() when a file is being truncated from nothing to allocate a contiguous run. The solution is to mark the pages dirty at the point of allocation by the truncation code. Signed-off-by: Enrik Berkhan <Enrik.Berkhan@ge.com> Signed-off-by: David Howells <dhowells@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Nick Piggin <nickpiggin@yahoo.com.au> Cc: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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