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* locks: break delegations on any attribute modificationJ. Bruce Fields2013-11-091-2/+2
| | | | | | | | | | | | | NFSv4 uses leases to guarantee that clients can cache metadata as well as data. Cc: Mikulas Patocka <mikulas@artax.karlin.mff.cuni.cz> Cc: David Howells <dhowells@redhat.com> Cc: Tyler Hicks <tyhicks@canonical.com> Cc: Dustin Kirkland <dustin.kirkland@gazzang.com> Acked-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* locks: break delegations on unlinkJ. Bruce Fields2013-11-091-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We need to break delegations on any operation that changes the set of links pointing to an inode. Start with unlink. Such operations also hold the i_mutex on a parent directory. Breaking a delegation may require waiting for a timeout (by default 90 seconds) in the case of a unresponsive NFS client. To avoid blocking all directory operations, we therefore drop locks before waiting for the delegation. The logic then looks like: acquire locks ... test for delegation; if found: take reference on inode release locks wait for delegation break drop reference on inode retry It is possible this could never terminate. (Even if we take precautions to prevent another delegation being acquired on the same inode, we could get a different inode on each retry.) But this seems very unlikely. The initial test for a delegation happens after the lock on the target inode is acquired, but the directory inode may have been acquired further up the call stack. We therefore add a "struct inode **" argument to any intervening functions, which we use to pass the inode back up to the caller in the case it needs a delegation synchronously broken. Cc: David Howells <dhowells@redhat.com> Cc: Tyler Hicks <tyhicks@canonical.com> Cc: Dustin Kirkland <dustin.kirkland@gazzang.com> Acked-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* driver core: handle user namespaces properly with the uid/gid devtmpfs changeGreg Kroah-Hartman2013-04-111-9/+9
| | | | | | | | | | | | | Now that devtmpfs is caring about uid/gid, we need to use the correct internal types so users who have USER_NS enabled will have things work properly for them. Thanks to Eric for pointing this out, and the patch review. Reported-by: Eric W. Biederman <ebiederm@xmission.com> Cc: Kay Sievers <kay@vrfy.org> Cc: Ming Lei <ming.lei@canonical.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* driver core: devtmpfs: fix compile failure with CONFIG_UIDGID_STRICT_TYPE_CHECKSMing Lei2013-04-101-2/+2
| | | | | | | | | | | | | | | | If CONFIG_UIDGID_STRICT_TYPE_CHECKS is enalbed, the below compile failure will be triggered: drivers/base/devtmpfs.c: In function 'handle_create': drivers/base/devtmpfs.c:214:19: error: incompatible types when assigning to type 'kuid_t' from type 'uid_t' drivers/base/devtmpfs.c:215:19: error: incompatible types when assigning to type 'kgid_t' from type 'gid_t' make[2]: *** [drivers/base/devtmpfs.o] Error 1 This patch fixes the compile failure. Signed-off-by: Ming Lei <ming.lei@canonical.com> Cc: Kay Sievers <kay@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* devtmpfs: add base.h includeGreg Kroah-Hartman2013-04-101-0/+1
| | | | | | | This fixes a sparse warning, and is a good idea given that the devtmpfs_init() prototype is in this file. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* driver core: add uid and gid to devtmpfsKay Sievers2013-04-081-10/+17
| | | | | | | | | | | | Some drivers want to tell userspace what uid and gid should be used for their device nodes, so allow that information to percolate through the driver core to userspace in order to make this happen. This means that some systems (i.e. Android and friends) will not need to even run a udev-like daemon for their device node manager and can just rely in devtmpfs fully, reducing their footprint even more. Signed-off-by: Kay Sievers <kay@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* switch vfs_getattr() to struct pathAl Viro2013-02-261-1/+2
| | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* vfs: turn is_dir argument to kern_path_create into a lookup_flags argJeff Layton2012-12-201-1/+1
| | | | | | | | Where we can pass in LOOKUP_DIRECTORY or LOOKUP_REVAL. Any other flags passed in here are currently ignored. Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* userns: Convert devtmpfs to use GLOBAL_ROOT_UID and GLOBAL_ROOT_GIDEric W. Biederman2012-09-211-2/+2
| | | | | | Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Serge Hallyn <serge.hallyn@canonical.com> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
* new helper: done_path_create()Al Viro2012-07-291-7/+2
| | | | | | releases what needs to be released after {kern,user}_path_create() Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* get rid of kern_path_parent()Al Viro2012-07-141-57/+41
| | | | | | | | | all callers want the same thing, actually - a kinda-sorta analog of kern_path_create(). I.e. they want parent vfsmount/dentry (with ->i_mutex held, to make sure the child dentry is still their child) + the child dentry. Signed-off-by Al Viro <viro@zeniv.linux.org.uk>
* devtmpfs: fix 'the the' typoPeter Korsgaard2012-04-181-3/+3
| | | | | Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Merge branch 'for-linus2' of ↵Linus Torvalds2012-01-081-4/+4
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs * 'for-linus2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (165 commits) reiserfs: Properly display mount options in /proc/mounts vfs: prevent remount read-only if pending removes vfs: count unlinked inodes vfs: protect remounting superblock read-only vfs: keep list of mounts for each superblock vfs: switch ->show_options() to struct dentry * vfs: switch ->show_path() to struct dentry * vfs: switch ->show_devname() to struct dentry * vfs: switch ->show_stats to struct dentry * switch security_path_chmod() to struct path * vfs: prefer ->dentry->d_sb to ->mnt->mnt_sb vfs: trim includes a bit switch mnt_namespace ->root to struct mount vfs: take /proc/*/mounts and friends to fs/proc_namespace.c vfs: opencode mntget() mnt_set_mountpoint() vfs: spread struct mount - remaining argument of next_mnt() vfs: move fsnotify junk to struct mount vfs: move mnt_devname vfs: move mnt_list to struct mount vfs: switch pnode.h macros to struct mount * ...
| * switch devtmpfs to umode_tAl Viro2012-01-031-3/+3
| | | | | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
| * switch device_get_devnode() and ->devnode() to umode_t *Al Viro2012-01-031-1/+1
| | | | | | | | | | | | | | both callers of device_get_devnode() are only interested in lower 16bits and nobody tries to return anything wider than 16bit anyway. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | devtmpfsd: fix task state handlingKautuk Consul2011-11-151-2/+1
|/ | | | | | | | | | | | | | - Set the state to TASK_INTERRUPTIBLE using __set_current_state() instead of set_current_state() as the spin_unlock is an implicit memory barrier. - After return from schedule(), there is no need to set the current state to TASK_RUNNING - a call to schedule() always returns in TASK_RUNNING state. Signed-off-by: Kautuk Consul <consul.kautuk@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* drivers/base/devtmpfs.c: correct annotation of `setup_done'Arnaud Lacombe2011-08-081-1/+1
| | | | | | | | | | | | | | | This fixes the following section mismatch issue: WARNING: vmlinux.o(.text+0x1192bf): Section mismatch in reference from the function devtmpfsd() to the variable .init.data:setup_done The function devtmpfsd() references the variable __initdata setup_done. This is often because devtmpfsd lacks a __initdata annotation or the annotation of setup_done is wrong. WARNING: vmlinux.o(.text+0x119342): Section mismatch in reference from the function devtmpfsd() to the variable .init.data:setup_done The function devtmpfsd() references the variable __initdata setup_done. This is often because devtmpfsd lacks a __initdata annotation or the annotation of setup_done is wrong. Signed-off-by: Arnaud Lacombe <lacombar@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* devtmpfs: missing initialialization in never-hit caseAl Viro2011-07-271-1/+1
| | | | | | | | | | | | create_path() on something without a single / in it will return err without initializing it. It actually can't happen (we call that thing only if create on the same path returns -ENOENT, which won't happen happen for single-component path), but in this case initializing err to 0 is more than making compiler to STFU - would be the right thing to return on such paths; the function creates a parent directory of given pathname and in that case it has no work to do... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* fix devtmpfs raceAl Viro2011-07-251-1/+2
| | | | | | | | After we's done complete(&req->done), there's nothing to prevent the scope containing *req from being gone and *req overwritten by any kind of junk. So we must read req->next before that... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* devtmpfs: get rid of bogus mkdir in create_path()Al Viro2011-07-201-24/+18
| | | | | | | | | We do _NOT_ want to mkdir the path itself - we are preparing to mknod it, after all. Normally it'll fail with -ENOENT and just do nothing, but if somebody has created the parent in the meanwhile, we'll get buggered... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* switch devtmpfs to kern_path_create()Al Viro2011-07-201-47/+36
| | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* switch devtmpfs object creation/removal to separate kernel threadAl Viro2011-07-201-73/+149
| | | | | | | | ... and give it a namespace where devtmpfs would be mounted on root, thus avoiding abuses of vfs_path_lookup() (it was never intended to be used with LOOKUP_PARENT). Games with credentials are also gone. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* convert get_sb_single() usersAl Viro2010-10-291-9/+9
| | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* devtmpfs: support !CONFIG_TMPFSPeter Korsgaard2010-05-211-0/+5
| | | | | | | | | | | | 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 Heo2010-03-301-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* Driver-Core: devtmpfs - reset inode permissions before unlinkingKay Sievers2010-03-071-0/+13
| | | | | | | | | | | | Before unlinking the inode, reset the current permissions of possible references like hardlinks, so granted permissions can not be retained across the device lifetime by creating hardlinks, in the unusual case that there is a user-writable directory on the same filesystem. Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Cc: stable <stable@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* driver-core: fix devtmpfs crash on s390Heiko Carstens2010-01-201-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On Mon, Jan 18, 2010 at 05:26:20PM +0530, Sachin Sant wrote: > Hello Heiko, > > Today while trying to boot next-20100118 i came across > the following Oops : > > Brought up 4 CPUs > Unable to handle kernel pointer dereference at virtual kernel address 0000000000 > 543000 > Oops: 0004 #1 SMP > Modules linked in: > CPU: 0 Not tainted 2.6.33-rc4-autotest-next-20100118-5-default #1 > Process swapper (pid: 1, task: 00000000fd792038, ksp: 00000000fd797a30) > Krnl PSW : 0704200180000000 00000000001eb0b8 (shmem_parse_options+0xc0/0x328) > R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:0 CC:2 PM:0 EA:3 > Krnl GPRS: 000000000054388a 000000000000003d 0000000000543836 000000000000003d > 0000000000000000 0000000000483f28 0000000000536112 00000000fd797d00 > 00000000fd4ba100 0000000000000100 0000000000483978 0000000000543832 > 0000000000000000 0000000000465958 00000000001eb0b0 00000000fd797c58 > Krnl Code: 00000000001eb0aa: c0e5000994f1 brasl %r14,31da8c > 00000000001eb0b0: b9020022 ltgr %r2,%r2 > 00000000001eb0b4: a784010b brc 8,1eb2ca > >00000000001eb0b8: 92002000 mvi 0(%r2),0 > 00000000001eb0bc: a7080000 lhi %r0,0 > 00000000001eb0c0: 41902001 la %r9,1(%r2) > 00000000001eb0c4: b9040016 lgr %r1,%r6 > 00000000001eb0c8: b904002b lgr %r2,%r11 > Call Trace: > (<00000000fd797c50> 0xfd797c50) > <00000000001eb5da> shmem_fill_super+0x13a/0x25c > <0000000000228cfa> get_sb_single+0xbe/0xdc > <000000000034ffc0> dev_get_sb+0x2c/0x38 > <000000000066c602> devtmpfs_init+0x46/0xc0 > <000000000066c53e> driver_init+0x22/0x60 > <000000000064d40a> kernel_init+0x24e/0x3d0 > <000000000010a7ea> kernel_thread_starter+0x6/0xc > <000000000010a7e4> kernel_thread_starter+0x0/0xc > > I never tried to boot a kernel with DEVTMPFS enabled on a s390 box. > So am wondering if this is supported or not ? If you think this > is supported i will send a mail to community on this. There is nothing arch specific to devtmpfs. This part crashes because the kernel tries to modify the data read-only section which is write protected on s390. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Acked-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* devtmpfs: unlock mutex in case of string allocation errorKay Sievers2009-12-231-2/+5
| | | | | | | Reported-by: Kirill A. Shutemov <kirill@shutemov.name> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* devtmpfs: Convert dirlock to a mutexThomas Gleixner2009-12-231-7/+5
| | | | | | | | | | | | | | | | | | | | | | devtmpfs has a rw_lock dirlock which serializes delete_path and create_path. This code was obviously never tested with the usual set of debugging facilities enabled. In the dirlock held sections the code calls: - vfs functions which take mutexes - kmalloc(, GFP_KERNEL) In both code pathes the might sleep warning triggers and spams dmesg. Convert the rw_lock to a mutex. There is no reason why this needs to be a rwlock. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Kay Sievers <kay.sievers@vrfy.org> Cc: stable <stable@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* Driver-Core: devtmpfs - set root directory mode to 0755Kay Sievers2009-12-111-1/+1
| | | | | | | Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Cc: Mark Rosenstand <rosenstand@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* Driver Core: devtmpfs: do not remove non-kernel-created directoriesKay Sievers2009-12-111-23/+16
| | | | | | Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* Driver Core: devtmpfs: use sys_mount()Kay Sievers2009-12-111-7/+2
| | | | | | Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* Driver core: devtmpfs: prevent concurrent subdirectory creation and removalKay Sievers2009-12-111-10/+16
| | | | | | Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* Driver Core: devtmpfs: ignore umask while setting file modeKay Sievers2009-12-111-10/+16
| | | | | | Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* Driver-Core: extend devnode callbacks to provide permissionsKay Sievers2009-09-191-8/+16
| | | | | | | | | | | | | This allows subsytems to provide devtmpfs with non-default permissions for the device node. Instead of the default mode of 0600, null, zero, random, urandom, full, tty, ptmx now have a mode of 0666, which allows non-privileged processes to access standard device nodes in case no other userspace process applies the expected permissions. This also fixes a wrong assignment in pktcdvd and a checkpatch.pl complain. Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* Driver Core: devtmpfs - kernel-maintained tmpfs-based /devKay Sievers2009-09-151-0/+367
Devtmpfs lets the kernel create a tmpfs instance called devtmpfs very early at kernel initialization, before any driver-core device is registered. Every device with a major/minor will provide a device node in devtmpfs. Devtmpfs can be changed and altered by userspace at any time, and in any way needed - just like today's udev-mounted tmpfs. Unmodified udev versions will run just fine on top of it, and will recognize an already existing kernel-created device node and use it. The default node permissions are root:root 0600. Proper permissions and user/group ownership, meaningful symlinks, all other policy still needs to be applied by userspace. If a node is created by devtmps, devtmpfs will remove the device node when the device goes away. If the device node was created by userspace, or the devtmpfs created node was replaced by userspace, it will no longer be removed by devtmpfs. If it is requested to auto-mount it, it makes init=/bin/sh work without any further userspace support. /dev will be fully populated and dynamic, and always reflect the current device state of the kernel. With the commonly used dynamic device numbers, it solves the problem where static devices nodes may point to the wrong devices. It is intended to make the initial bootup logic simpler and more robust, by de-coupling the creation of the inital environment, to reliably run userspace processes, from a complex userspace bootstrap logic to provide a working /dev. Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Jan Blunck <jblunck@suse.de> Tested-By: Harald Hoyer <harald@redhat.com> Tested-By: Scott James Remnant <scott@ubuntu.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
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