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* Merge branch 'for-linus' of ↵Linus Torvalds2007-10-171-6/+16
|\ | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/ericvh/v9fs * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ericvh/v9fs: 9p: remove sysctl 9p: fix bad kconfig cross-dependency 9p: soften invalidation in loose_mode 9p: attach-per-user 9p: rename uid and gid parameters 9p: define session flags 9p: Make transports dynamic
| * 9p: attach-per-userLatchesar Ionkov2007-10-171-0/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The 9P2000 protocol requires the authentication and permission checks to be done in the file server. For that reason every user that accesses the file server tree has to authenticate and attach to the server separately. Multiple users can share the same connection to the server. Currently v9fs does a single attach and executes all I/O operations as a single user. This makes using v9fs in multiuser environment unsafe as it depends on the client doing the permission checking. This patch improves the 9P2000 support by allowing every user to attach separately. The patch defines three modes of access (new mount option 'access'): - attach-per-user (access=user) (default mode for 9P2000.u) If a user tries to access a file served by v9fs for the first time, v9fs sends an attach command to the server (Tattach) specifying the user. If the attach succeeds, the user can access the v9fs tree. As there is no uname->uid (string->integer) mapping yet, this mode works only with the 9P2000.u dialect. - allow only one user to access the tree (access=<uid>) Only the user with uid can access the v9fs tree. Other users that attempt to access it will get EPERM error. - do all operations as a single user (access=any) (default for 9P2000) V9fs does a single attach and all operations are done as a single user. If this mode is selected, the v9fs behavior is identical with the current one. Signed-off-by: Latchesar Ionkov <lucho@ionkov.net> Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
| * 9p: rename uid and gid parametersLatchesar Ionkov2007-10-171-2/+2
| | | | | | | | | | | | | | | | | | | | Change the names of 'uid' and 'gid' parameters to the more appropriate 'dfltuid' and 'dfltgid'. This also sets the default uid/gid to -2 (aka nfsnobody) Signed-off-by: Latchesar Ionkov <lucho@ionkov.net> Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
| * 9p: Make transports dynamicEric Van Hensbergen2007-10-171-4/+4
| | | | | | | | | | | | | | | | | | This patch abstracts out the interfaces to underlying transports so that new transports can be added as modules. This should also allow kernel configuration of transports without ifdef-hell. Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
* | x86: expand /proc/interrupts to include missing vectors, v2Joe Korty2007-10-171-1/+29
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add missing IRQs and IRQ descriptions to /proc/interrupts. /proc/interrupts is most useful when it displays every IRQ vector in use by the system, not just those somebody thought would be interesting. This patch inserts the following vector displays to the i386 and x86_64 platforms, as appropriate: rescheduling interrupts TLB flush interrupts function call interrupts thermal event interrupts threshold interrupts spurious interrupts A threshold interrupt occurs when ECC memory correction is occuring at too high a frequency. Thresholds are used by the ECC hardware as occasional ECC failures are part of normal operation, but long sequences of ECC failures usually indicate a memory chip that is about to fail. Thermal event interrupts occur when a temperature threshold has been exceeded for some CPU chip. IIRC, a thermal interrupt is also generated when the temperature drops back to a normal level. A spurious interrupt is an interrupt that was raised then lowered by the device before it could be fully processed by the APIC. Hence the apic sees the interrupt but does not know what device it came from. For this case the APIC hardware will assume a vector of 0xff. Rescheduling, call, and TLB flush interrupts are sent from one CPU to another per the needs of the OS. Typically, their statistics would be used to discover if an interrupt flood of the given type has been occuring. AK: merged v2 and v4 which had some more tweaks AK: replace Local interrupts with Local timer interrupts AK: Fixed description of interrupt types. [ tglx: arch/x86 adaptation ] [ mingo: small cleanup ] Signed-off-by: Joe Korty <joe.korty@ccur.com> Signed-off-by: Andi Kleen <ak@suse.de> Cc: Tim Hockin <thockin@hockin.org> Cc: Andi Kleen <ak@suse.de> Cc: Ingo Molnar <mingo@elte.hu> Cc: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* Documentation: add entries to filesystems/00-INDEX for several untracked filesDenis Cheng2007-10-171-0/+6
| | | | | | | | Signed-off-by: Denis Cheng <crquan@gmail.com> Cc: Rob Landley <rob@landley.net> Cc: "Randy.Dunlap" <rdunlap@xenotime.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* quota: send messages via netlinkJan Kara2007-10-171-0/+59
| | | | | | | | | | | | | Implement sending of quota messages via netlink interface. The advantage is that in userspace we can better decide what to do with the message - for example display a dialogue in your X session or just write the message to the console. As a bonus, we can get rid of problems with console locking deep inside filesystem code once we remove the old printing mechanism. Signed-off-by: Jan Kara <jack@suse.cz> Cc: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* docs: ramdisk/initrd/initramfs correctionsRandy Dunlap2007-10-171-7/+7
| | | | | | | | | | | | | | | | initrd/initramfs/ramdisk docs: - fix typos/spellos/grammar - clarify RAM disk config location - correct cpio option Acked-by: Bryan O'Sullivan <bos@serpentine.com> Acked-by: Rob Landley <rob@landley.net> Cc: Werner Almesberger <werner@almesberger.net> Cc: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Acked-by: Jesper Juhl <jesper.juhl@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* fs: remove some AOP_TRUNCATED_PAGENick Piggin2007-10-161-5/+1
| | | | | | | | | | | | | | | prepare/commit_write no longer returns AOP_TRUNCATED_PAGE since OCFS2 and GFS2 were converted to the new aops, so we can make some simplifications for that. [michal.k.k.piotrowski@gmail.com: fix warning] Signed-off-by: Nick Piggin <npiggin@suse.de> Cc: Michael Halcrow <mhalcrow@us.ibm.com> Cc: Mark Fasheh <mark.fasheh@oracle.com> Cc: Steven Whitehouse <swhiteho@redhat.com> Signed-off-by: Michal Piotrowski <michal.k.k.piotrowski@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* fs: introduce write_begin, write_end, and perform_write aopsNick Piggin2007-10-162-3/+51
| | | | | | | | | | | | | | | These are intended to replace prepare_write and commit_write with more flexible alternatives that are also able to avoid the buffered write deadlock problems efficiently (which prepare_write is unable to do). [mark.fasheh@oracle.com: API design contributions, code review and fixes] [akpm@linux-foundation.org: various fixes] [dmonakhov@sw.ru: new aop block_write_begin fix] Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com> Signed-off-by: Dmitriy Monakhov <dmonakhov@openvz.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge branch 'locks' of git://linux-nfs.org/~bfields/linuxLinus Torvalds2007-10-153-0/+242
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * 'locks' of git://linux-nfs.org/~bfields/linux: nfsd: remove IS_ISMNDLCK macro Rework /proc/locks via seq_files and seq_list helpers fs/locks.c: use list_for_each_entry() instead of list_for_each() NFS: clean up explicit check for mandatory locks AFS: clean up explicit check for mandatory locks 9PFS: clean up explicit check for mandatory locks GFS2: clean up explicit check for mandatory locks Cleanup macros for distinguishing mandatory locks Documentation: move locks.txt in filesystems/ locks: add warning about mandatory locking races Documentation: move mandatory locking documentation to filesystems/ locks: Fix potential OOPS in generic_setlease() Use list_first_entry in locks_wake_up_blocks locks: fix flock_lock_file() comment Memory shortage can result in inconsistent flocks state locks: kill redundant local variable locks: reverse order of posix_locks_conflict() arguments
| * Documentation: move locks.txt in filesystems/J. Bruce Fields2007-10-092-0/+69
| | | | | | | | | | | | This documentation (about file locking) belongs in filesystems/. Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
| * locks: add warning about mandatory locking racesJ. Bruce Fields2007-10-091-1/+20
| | | | | | | | | | | | | | | | The mandatory file locking implementation has long-standing races that probably render it useless. I know of no plans to fix them. Till we do, we should at least warn people. Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
| * Documentation: move mandatory locking documentation to filesystems/J. Bruce Fields2007-10-092-0/+154
| | | | | | | | | | | | | | | | | | | | | | | | Shouldn't this mandatory-locking documentation be in the Documentation/filesystems directory? Give it a more descriptive name while we're at it, and update 00-INDEX with a more inclusive description of Documentation/filesystems (which has already talked about more than just individual filesystems). Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu> Acked-by: Randy Dunlap <randy.dunlap@oracle.com>
* | NTFS: Fix a mount time deadlock.Anton Altaparmakov2007-10-121-1/+3
|/ | | | | | | | | | | | | | | | | | | | | | Big thanks go to Mathias Kolehmainen for reporting the bug, providing debug output and testing the patches I sent him to get it working. The fix was to stop calling ntfs_attr_set() at mount time as that causes balance_dirty_pages_ratelimited() to be called which on systems with little memory actually tries to go and balance the dirty pages which tries to take the s_umount semaphore but because we are still in fill_super() across which the VFS holds s_umount for writing this results in a deadlock. We now do the dirty work by hand by submitting individual buffers. This has the annoying "feature" that mounting can take a few seconds if the journal is large as we have clear it all. One day someone should improve on this by deferring the journal clearing to a helper kernel thread so it can be done in the background but I don't have time for this at the moment and the current solution works fine so I am leaving it like this for now. Signed-off-by: Anton Altaparmakov <aia21@cantab.net> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge branch 'upstream-linus' of ↵Linus Torvalds2007-09-111-4/+9
|\ | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/mfasheh/ocfs2 * 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mfasheh/ocfs2: ocfs2: Fix calculation of i_blocks during truncate [PATCH] ocfs2: Fix a wrong cluster calculation. [PATCH] ocfs2: fix mount option parsing ocfs2: update docs for new features
| * ocfs2: update docs for new featuresMark Fasheh2007-09-111-4/+9
| | | | | | | | | | | | | | | | Update documentation listing ocfs2 features to reflect the current state of the file system. Add missing descriptions for some mount options which ocfs2 supports. Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
* | Documentation/00-INDEX: notice ecryptfs.txt movedRob Landley2007-09-111-0/+2
|/ | | | | | | | | ecryptfs.txt moved into filesystems, make 00-INDEX follow. Signed-off-by: Rob Landley <rob@landley.net> Cc: Michael Halcrow <mhalcrow@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 9p: update maintainers and documentationEric Van Hensbergen2007-08-231-5/+19
| | | | | | | | | Updates to the MAINTAINERS file and documentation for 9p to point to the swik wiki versus the outdated sf.net page. Also updated some email addresses and added pointers to papers which better describe the implementation and application of the Linux 9p client. Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
* Documentation: document HFSPlusWyatt Banks2007-07-311-0/+59
| | | | | | | | | | Documentation: document HFSPlus filesystem and its mount options. Signed-off-by: Wyatt Banks <wyatt@banksresearch.com> Cc: "Randy.Dunlap" <rdunlap@xenotime.net> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* some kmalloc/memset ->kzalloc (tree wide)Yoann Padioleau2007-07-191-4/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Transform some calls to kmalloc/memset to a single kzalloc (or kcalloc). Here is a short excerpt of the semantic patch performing this transformation: @@ type T2; expression x; identifier f,fld; expression E; expression E1,E2; expression e1,e2,e3,y; statement S; @@ x = - kmalloc + kzalloc (E1,E2) ... when != \(x->fld=E;\|y=f(...,x,...);\|f(...,x,...);\|x=E;\|while(...) S\|for(e1;e2;e3) S\) - memset((T2)x,0,E1); @@ expression E1,E2,E3; @@ - kzalloc(E1 * E2,E3) + kcalloc(E1,E2,E3) [akpm@linux-foundation.org: get kcalloc args the right way around] Signed-off-by: Yoann Padioleau <padator@wanadoo.fr> Cc: Richard Henderson <rth@twiddle.net> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Acked-by: Russell King <rmk@arm.linux.org.uk> Cc: Bryan Wu <bryan.wu@analog.com> Acked-by: Jiri Slaby <jirislaby@gmail.com> Cc: Dave Airlie <airlied@linux.ie> Acked-by: Roland Dreier <rolandd@cisco.com> Cc: Jiri Kosina <jkosina@suse.cz> Acked-by: Dmitry Torokhov <dtor@mail.ru> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Acked-by: Mauro Carvalho Chehab <mchehab@infradead.org> Acked-by: Pierre Ossman <drzeus-list@drzeus.cx> Cc: Jeff Garzik <jeff@garzik.org> Cc: "David S. Miller" <davem@davemloft.net> Acked-by: Greg KH <greg@kroah.com> Cc: James Bottomley <James.Bottomley@steeleye.com> Cc: "Antonino A. Daplas" <adaplas@pol.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* coredump masking: documentation for /proc/pid/coredump_filterKawai, Hidehiro2007-07-191-0/+38
| | | | | | | | | | | | | This patch adds the documentation for /proc/<pid>/coredump_filter. Signed-off-by: Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: David Howells <dhowells@redhat.com> Cc: Hugh Dickins <hugh@veritas.com> Cc: Nick Piggin <nickpiggin@yahoo.com.au> Cc: "Randy.Dunlap" <rdunlap@xenotime.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* audit: rework execve auditPeter Zijlstra2007-07-191-0/+7
| | | | | | | | | | | | | | | | | | | | | | | The purpose of audit_bprm() is to log the argv array to a userspace daemon at the end of the execve system call. Since user-space hasn't had time to run, this array is still in pristine state on the process' stack; so no need to copy it, we can just grab it from there. In order to minimize the damage to audit_log_*() copy each string into a temporary kernel buffer first. Currently the audit code requires that the full argument vector fits in a single packet. So currently it does clip the argv size to a (sysctl) limit, but only when execve auditing is enabled. If the audit protocol gets extended to allow for multiple packets this check can be removed. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Ollie Wild <aaw@google.com> Cc: <linux-audit@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: fault feedback #1Nick Piggin2007-07-191-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | Change ->fault prototype. We now return an int, which contains VM_FAULT_xxx code in the low byte, and FAULT_RET_xxx code in the next byte. FAULT_RET_ code tells the VM whether a page was found, whether it has been locked, and potentially other things. This is not quite the way he wanted it yet, but that's changed in the next patch (which requires changes to arch code). This means we no longer set VM_CAN_INVALIDATE in the vma in order to say that a page is locked which requires filemap_nopage to go away (because we can no longer remain backward compatible without that flag), but we were going to do that anyway. struct fault_data is renamed to struct vm_fault as Linus asked. address is now a void __user * that we should firmly encourage drivers not to use without really good reason. The page is now returned via a page pointer in the vm_fault struct. Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Document ->page_mkwrite() lockingMark Fasheh2007-07-191-1/+10
| | | | | | | | | | | | There seems to be very little documentation about this callback in general. The locking in particular is a bit tricky, so it's worth having this in writing. Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com> Cc: Nick Piggin <nickpiggin@yahoo.com.au> Cc: David Howells <dhowells@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: merge populate and nopage into fault (fixes nonlinear)Nick Piggin2007-07-191-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Nonlinear mappings are (AFAIKS) simply a virtual memory concept that encodes the virtual address -> file offset differently from linear mappings. ->populate is a layering violation because the filesystem/pagecache code should need to know anything about the virtual memory mapping. The hitch here is that the ->nopage handler didn't pass down enough information (ie. pgoff). But it is more logical to pass pgoff rather than have the ->nopage function calculate it itself anyway (because that's a similar layering violation). Having the populate handler install the pte itself is likewise a nasty thing to be doing. This patch introduces a new fault handler that replaces ->nopage and ->populate and (later) ->nopfn. Most of the old mechanism is still in place so there is a lot of duplication and nice cleanups that can be removed if everyone switches over. The rationale for doing this in the first place is that nonlinear mappings are subject to the pagefault vs invalidate/truncate race too, and it seemed stupid to duplicate the synchronisation logic rather than just consolidate the two. After this patch, MAP_NONBLOCK no longer sets up ptes for pages present in pagecache. Seems like a fringe functionality anyway. NOPAGE_REFAULT is removed. This should be implemented with ->fault, and no users have hit mainline yet. [akpm@linux-foundation.org: cleanup] [randy.dunlap@oracle.com: doc. fixes for readahead] [akpm@linux-foundation.org: build fix] Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Cc: Mark Fasheh <mark.fasheh@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* eCryptfs: Move ecryptfs docs into Documentation/filesystems/Josef 'Jeff' Sipek2007-07-171-0/+77
| | | | | | | Signed-off-by: Josef 'Jeff' Sipek <jsipek@cs.sunysb.edu> Acked-by: Michael Halcrow <mhalcrow@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* handle kernelcore=: genericMel Gorman2007-07-171-0/+15
| | | | | | | | | | | | | | | | | | | | | | | | | This patch adds the kernelcore= parameter for x86. Once all patches are applied, a new command-line parameter exist and a new sysctl. This patch adds the necessary documentation. From: Yasunori Goto <y-goto@jp.fujitsu.com> When "kernelcore" boot option is specified, kernel can't boot up on ia64 because of an infinite loop. In addition, the parsing code can be handled in an architecture-independent manner. This patch uses common code to handle the kernelcore= parameter. It is only available to architectures that support arch-independent zone-sizing (i.e. define CONFIG_ARCH_POPULATES_NODE_MAP). Other architectures will ignore the boot parameter. [bunk@stusta.de: make cmdline_parse_kernelcore() static] Signed-off-by: Mel Gorman <mel@csn.ul.ie> Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com> Acked-by: Andy Whitcroft <apw@shadowen.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge branch 'upstream-linus' of ↵Linus Torvalds2007-07-162-10/+49
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/mfasheh/ocfs2 * 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mfasheh/ocfs2: (32 commits) [PATCH] ocfs2: zero_user_page conversion ocfs2: Support xfs style space reservation ioctls ocfs2: support for removing file regions ocfs2: update truncate handling of partial clusters ocfs2: btree support for removal of arbirtrary extents ocfs2: Support creation of unwritten extents ocfs2: support writing of unwritten extents ocfs2: small cleanup of ocfs2_write_begin_nolock() ocfs2: btree changes for unwritten extents ocfs2: abstract btree growing calls ocfs2: use all extent block suballocators ocfs2: plug truncate into cached dealloc routines ocfs2: simplify deallocation locking ocfs2: harden buffer check during mapping of page blocks ocfs2: shared writeable mmap ocfs2: factor out write aops into nolock variants ocfs2: rework ocfs2_buffered_write_cluster() ocfs2: take ip_alloc_sem during entire truncate ocfs2: Add "preferred slot" mount option [KJ PATCH] Replacing memset(<addr>,0,PAGE_SIZE) with clear_page() in fs/ocfs2/dlm/dlmrecovery.c ...
| * configfs: config item dependancies.Joel Becker2007-07-101-0/+27
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Sometimes other drivers depend on particular configfs items. For example, ocfs2 mounts depend on a heartbeat region item. If that region item is removed with rmdir(2), the ocfs2 mount must BUG or go readonly. Not happy. This provides two additional API calls: configfs_depend_item() and configfs_undepend_item(). A client driver can call configfs_depend_item() on an existing item to tell configfs that it is depended on. configfs will then return -EBUSY from rmdir(2) for that item. When the item is no longer depended on, the client driver calls configfs_undepend_item() on it. These API cannot be called underneath any configfs callbacks, as they will conflict. They can block and allocate. A client driver probably shouldn't calling them of its own gumption. Rather it should be providing an API that external subsystems call. How does this work? Imagine the ocfs2 mount process. When it mounts, it asks for a heart region item. This is done via a call into the heartbeat code. Inside the heartbeat code, the region item is looked up. Here, the heartbeat code calls configfs_depend_item(). If it succeeds, then heartbeat knows the region is safe to give to ocfs2. If it fails, it was being torn down anyway, and heartbeat can gracefully pass up an error. [ Fixed some bad whitespace in configfs.txt. --Mark ] Signed-off-by: Joel Becker <joel.becker@oracle.com> Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
| * configfs: accessing item hierarchy during rmdir(2)Joel Becker2007-07-101-0/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add a notification callback, ops->disconnect_notify(). It has the same prototype as ->drop_item(), but it will be called just before the item linkage is broken. This way, configfs users who want to do work while the object is still in the heirarchy have a chance. Client drivers will still need to config_item_put() in their ->drop_item(), if they implement it. They need do nothing in ->disconnect_notify(). They don't have to provide it if they don't care. But someone who wants to be notified before ci_parent is set to NULL can now be notified. Signed-off-by: Joel Becker <joel.becker@oracle.com> Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
| * configfs: Convert subsystem semaphore to mutexJoel Becker2007-07-102-10/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Convert the su_sem member of struct configfs_subsystem to a struct mutex, as that's what it is. Also convert all the users and update Documentation/configfs.txt and Documentation/configfs_example.c accordingly. [ Conflict in fs/dlm/config.c with commit 3168b0780d06ace875696f8a648d04d6089654e5 manually resolved. --Mark ] Inspired-by: Satyam Sharma <ssatyam@cse.iitk.ac.in> Signed-off-by: Joel Becker <joel.becker@oracle.com> Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
* | update Documentation/filesystems/vfs.txtBorislav Petkov2007-07-161-13/+16
| | | | | | | | | | | | | | | | Update Documentation/filesystems/vfs.txt Signed-off-by: Borislav Petkov <bbpetkov@yahoo.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | update description in Documentation/filesystems/vfs.txtBorislav Petkov2007-07-161-9/+13
| | | | | | | | | | | | | | | | | | Update the description of struct file_system_type and get_sb() in Documentation/filesystems/vfs.txt to match the current code. Signed-off-by: Borislav Petkov <bbpetkov@yahoo.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | Documentation: /proc/$pid/stat filesKees Cook2007-07-161-7/+58
|/ | | | | | | | | Documentation for the /proc/$pid/stat file. Signed-off-by: Kees Cook <kees@outflux.net> Cc: Rob Landley <rob@landley.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mount -t tmpfs -o mpol=: check nodes onlineHugh Dickins2007-06-081-5/+5
| | | | | | | | | | | | | | Randy Dunlap reports that a tmpfs, mounted with NUMA mpol= specifying an offline node, crashes as soon as data is allocated upon it. Now restrict it to online nodes, where before it restricted to MAX_NUMNODES. Signed-off-by: Hugh Dickins <hugh@veritas.com> Cc: Robin Holt <holt@sgi.com> Cc: Christoph Lameter <clameter@sgi.com> Cc: Andi Kleen <ak@suse.de> Tested-and-acked-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Documentation: Fix up docs still talking about i_semJosef 'Jeff' Sipek2007-05-242-6/+7
| | | | | | | .. it got changed to 'i_mutex' some time ago. Signed-off-by: Josef 'Jeff' Sipek <jsipek@cs.sunysb.edu> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* trivial: s/i_sem /i_mutex/Artem Bityutskiy2007-05-091-3/+3
| | | | | | | | | This patch substitutes i_sem by i_mutex in Documentation/filesystems/Locking. The patch also removes a couple of trailing white-spaces. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com> Signed-off-by: Adrian Bunk <bunk@stusta.de>
* misc doc and kconfig typosMatt LaPlante2007-05-094-4/+4
| | | | | | | Fix various typos in kernel docs and Kconfigs, 2.6.21-rc4. Signed-off-by: Matt LaPlante <kernel1@cyberdogtech.com> Signed-off-by: Adrian Bunk <bunk@stusta.de>
* Fix more "deprecated" spellos.Randy Dunlap2007-05-091-1/+1
| | | | | Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Adrian Bunk <bunk@stusta.de>
* Merge branch 'for-linus' of ↵Linus Torvalds2007-05-081-1/+7
|\ | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/shaggy/jfs-2.6 * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/shaggy/jfs-2.6: JFS: Fix race waking up jfsIO kernel thread JFS: use __set_current_state() Copy i_flags to jfs inode flags on write JFS: document uid, gid, and umask mount options in jfs.txt
| * JFS: document uid, gid, and umask mount options in jfs.txtDave Kleikamp2007-03-091-1/+7
| | | | | | | | Signed-off-by: Dave Kleikamp <shaggy@austin.ibm.com>
* | fat: don't use free_clusters for fat32OGAWA Hirofumi2007-05-081-0/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | It seems that the recent Windows changed specification, and it's undocumented. Windows doesn't update ->free_clusters correctly. This patch doesn't use ->free_clusters by default. (instead, add "usefree" for forcing to use it) Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Cc: Juergen Beisert <juergen127@kreuzholzen.de> Cc: Andreas Schwab <schwab@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | VFS: delay the dentry name generation on sockets and pipesEric Dumazet2007-05-082-1/+24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 1) Introduces a new method in 'struct dentry_operations'. This method called d_dname() might be called from d_path() to build a pathname for special filesystems. It is called without locks. Future patches (if we succeed in having one common dentry for all pipes/sockets) may need to change prototype of this method, but we now use : char *d_dname(struct dentry *dentry, char *buffer, int buflen); 2) Adds a dynamic_dname() helper function that eases d_dname() implementations 3) Defines d_dname method for sockets : No more sprintf() at socket creation. This is delayed up to the moment someone does an access to /proc/pid/fd/... 4) Defines d_dname method for pipes : No more sprintf() at pipe creation. This is delayed up to the moment someone does an access to /proc/pid/fd/... A benchmark consisting of 1.000.000 calls to pipe()/close()/close() gives a *nice* speedup on my Pentium(M) 1.6 Ghz : 3.090 s instead of 3.450 s Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Acked-by: Christoph Hellwig <hch@infradead.org> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | proc: maps protectionKees Cook2007-05-081-0/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The /proc/pid/ "maps", "smaps", and "numa_maps" files contain sensitive information about the memory location and usage of processes. Issues: - maps should not be world-readable, especially if programs expect any kind of ASLR protection from local attackers. - maps cannot just be 0400 because "-D_FORTIFY_SOURCE=2 -O2" makes glibc check the maps when %n is in a *printf call, and a setuid(getuid()) process wouldn't be able to read its own maps file. (For reference see http://lkml.org/lkml/2006/1/22/150) - a system-wide toggle is needed to allow prior behavior in the case of non-root applications that depend on access to the maps contents. This change implements a check using "ptrace_may_attach" before allowing access to read the maps contents. To control this protection, the new knob /proc/sys/kernel/maps_protect has been added, with corresponding updates to the procfs documentation. [akpm@linux-foundation.org: build fixes] [akpm@linux-foundation.org: New sysctl numbers are old hat] Signed-off-by: Kees Cook <kees@outflux.net> Cc: Arjan van de Ven <arjan@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | smaps: add clear_refs file to clear referenceDavid Rientjes2007-05-071-15/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Adds /proc/pid/clear_refs. When any non-zero number is written to this file, pte_mkold() and ClearPageReferenced() is called for each pte and its corresponding page, respectively, in that task's VMAs. This file is only writable by the user who owns the task. It is now possible to measure _approximately_ how much memory a task is using by clearing the reference bits with echo 1 > /proc/pid/clear_refs and checking the reference count for each VMA from the /proc/pid/smaps output at a measured time interval. For example, to observe the approximate change in memory footprint for a task, write a script that clears the references (echo 1 > /proc/pid/clear_refs), sleeps, and then greps for Pgs_Referenced and extracts the size in kB. Add the sizes for each VMA together for the total referenced footprint. Moments later, repeat the process and observe the difference. For example, using an efficient Mozilla: accumulated time referenced memory ---------------- ----------------- 0 s 408 kB 1 s 408 kB 2 s 556 kB 3 s 1028 kB 4 s 872 kB 5 s 1956 kB 6 s 416 kB 7 s 1560 kB 8 s 2336 kB 9 s 1044 kB 10 s 416 kB This is a valuable tool to get an approximate measurement of the memory footprint for a task. Cc: Hugh Dickins <hugh@veritas.com> Cc: Paul Mundt <lethal@linux-sh.org> Cc: Christoph Lameter <clameter@sgi.com> Signed-off-by: David Rientjes <rientjes@google.com> [akpm@linux-foundation.org: build fixes] [mpm@selenic.com: rename for_each_pmd] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | [AFS]: Update the AFS fs documentation.David Howells2007-04-261-60/+154
| | | | | | | | | | | | | | Update the AFS fs documentation. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | [NET]: Replace CONFIG_NET_DEBUG with sysctl.Stephen Hemminger2007-04-251-0/+9
|/ | | | | | | | Covert network warning messages from a compile time to runtime choice. Removes kernel config option and replaces it with new /proc/sys/net/core/warnings. Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
* [PATCH] Documentation for io-accounting / reporting via procfsRoland Kletzing2007-03-051-0/+105
| | | | | | | | | Add some documentation for the new and very useful io-accounting feature. It's being added to Documentation/filesystems/proc.txt Signed-off-by: Roland Kletzing <devzero@web.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [PATCH] fs: fix libfs data leakNick Piggin2007-02-201-0/+5
| | | | | | | | | | | | | | | | | | simple_prepare_write leaks uninitialised kernel data. This happens because the it leaves an uninitialised "hole" over the part of the page that the write is expected to go to. This is fine, but it then marks the page uptodate, which means a concurrent read can come in and copy the uninitialised memory into userspace before it written to. Fix it by simply marking it uptodate in simple_commit_write instead, after the hole has been filled in. This could theoretically break an fs that uses simple_prepare_write and not simple_commit_write, and that relies on the incorrect simple_prepare_write behaviour. Luckily, none of those exists in the tree. Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>