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* dlm: check the maximum size of a request from userSasha Levin2012-09-101-0/+7
| | | | | | | | | | | | device_write only checks whether the request size is big enough, but it doesn't check if the size is too big. At that point, it also tries to allocate as much memory as the user has requested even if it's too much. This can lead to OOM killer kicking in, or memory corruption if (count + 1) overflows. Signed-off-by: Sasha Levin <levinsasha928@gmail.com> Signed-off-by: David Teigland <teigland@redhat.com>
* dlm: add recovery callbacksDavid Teigland2012-01-041-2/+3
| | | | | | | | | | | | | These new callbacks notify the dlm user about lock recovery. GFS2, and possibly others, need to be aware of when the dlm will be doing lock recovery for a failed lockspace member. In the past, this coordination has been done between dlm and file system daemons in userspace, which then direct their kernel counterparts. These callbacks allow the same coordination directly, and more simply. Signed-off-by: David Teigland <teigland@redhat.com>
* dlm: use workqueue for callbacksDavid Teigland2011-07-151-6/+6
| | | | | | | | | Instead of creating our own kthread (dlm_astd) to deliver callbacks for all lockspaces, use a per-lockspace workqueue to deliver the callbacks. This eliminates complications and slowdowns from many lockspaces sharing the same thread. Signed-off-by: David Teigland <teigland@redhat.com>
* dlm: Remove superfluous call to recalc_sigpending()Matt Fleming2011-03-281-1/+0
| | | | | | | | recalc_sigpending() is called within sigprocmask(), so there is no need call it again after sigprocmask() has returned. Signed-off-by: Matt Fleming <matt.fleming@linux.intel.com> Signed-off-by: David Teigland <teigland@redhat.com>
* dlm: record full callback stateDavid Teigland2011-03-101-121/+64
| | | | | | | | | | | | | Change how callbacks are recorded for locks. Previously, information about multiple callbacks was combined into a couple of variables that indicated what the end result should be. In some situations, we could not tell from this combined state what the exact sequence of callbacks were, and would end up either delivering the callbacks in the wrong order, or suppress redundant callbacks incorrectly. This new approach records all the data for each callback, leaving no uncertainty about what needs to be delivered. Signed-off-by: David Teigland <teigland@redhat.com>
* llseek: automatically add .llseek fopArnd Bergmann2010-10-151-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | All file_operations should get a .llseek operation so we can make nonseekable_open the default for future file operations without a .llseek pointer. The three cases that we can automatically detect are no_llseek, seq_lseek and default_llseek. For cases where we can we can automatically prove that the file offset is always ignored, we use noop_llseek, which maintains the current behavior of not returning an error from a seek. New drivers should normally not use noop_llseek but instead use no_llseek and call nonseekable_open at open time. Existing drivers can be converted to do the same when the maintainer knows for certain that no user code relies on calling seek on the device file. The generated code is often incorrectly indented and right now contains comments that clarify for each added line why a specific variant was chosen. In the version that gets submitted upstream, the comments will be gone and I will manually fix the indentation, because there does not seem to be a way to do that using coccinelle. Some amount of new code is currently sitting in linux-next that should get the same modifications, which I will do at the end of the merge window. Many thanks to Julia Lawall for helping me learn to write a semantic patch that does all this. ===== begin semantic patch ===== // This adds an llseek= method to all file operations, // as a preparation for making no_llseek the default. // // The rules are // - use no_llseek explicitly if we do nonseekable_open // - use seq_lseek for sequential files // - use default_llseek if we know we access f_pos // - use noop_llseek if we know we don't access f_pos, // but we still want to allow users to call lseek // @ open1 exists @ identifier nested_open; @@ nested_open(...) { <+... nonseekable_open(...) ...+> } @ open exists@ identifier open_f; identifier i, f; identifier open1.nested_open; @@ int open_f(struct inode *i, struct file *f) { <+... ( nonseekable_open(...) | nested_open(...) ) ...+> } @ read disable optional_qualifier exists @ identifier read_f; identifier f, p, s, off; type ssize_t, size_t, loff_t; expression E; identifier func; @@ ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off) { <+... ( *off = E | *off += E | func(..., off, ...) | E = *off ) ...+> } @ read_no_fpos disable optional_qualifier exists @ identifier read_f; identifier f, p, s, off; type ssize_t, size_t, loff_t; @@ ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off) { ... when != off } @ write @ identifier write_f; identifier f, p, s, off; type ssize_t, size_t, loff_t; expression E; identifier func; @@ ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off) { <+... ( *off = E | *off += E | func(..., off, ...) | E = *off ) ...+> } @ write_no_fpos @ identifier write_f; identifier f, p, s, off; type ssize_t, size_t, loff_t; @@ ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off) { ... when != off } @ fops0 @ identifier fops; @@ struct file_operations fops = { ... }; @ has_llseek depends on fops0 @ identifier fops0.fops; identifier llseek_f; @@ struct file_operations fops = { ... .llseek = llseek_f, ... }; @ has_read depends on fops0 @ identifier fops0.fops; identifier read_f; @@ struct file_operations fops = { ... .read = read_f, ... }; @ has_write depends on fops0 @ identifier fops0.fops; identifier write_f; @@ struct file_operations fops = { ... .write = write_f, ... }; @ has_open depends on fops0 @ identifier fops0.fops; identifier open_f; @@ struct file_operations fops = { ... .open = open_f, ... }; // use no_llseek if we call nonseekable_open //////////////////////////////////////////// @ nonseekable1 depends on !has_llseek && has_open @ identifier fops0.fops; identifier nso ~= "nonseekable_open"; @@ struct file_operations fops = { ... .open = nso, ... +.llseek = no_llseek, /* nonseekable */ }; @ nonseekable2 depends on !has_llseek @ identifier fops0.fops; identifier open.open_f; @@ struct file_operations fops = { ... .open = open_f, ... +.llseek = no_llseek, /* open uses nonseekable */ }; // use seq_lseek for sequential files ///////////////////////////////////// @ seq depends on !has_llseek @ identifier fops0.fops; identifier sr ~= "seq_read"; @@ struct file_operations fops = { ... .read = sr, ... +.llseek = seq_lseek, /* we have seq_read */ }; // use default_llseek if there is a readdir /////////////////////////////////////////// @ fops1 depends on !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier readdir_e; @@ // any other fop is used that changes pos struct file_operations fops = { ... .readdir = readdir_e, ... +.llseek = default_llseek, /* readdir is present */ }; // use default_llseek if at least one of read/write touches f_pos ///////////////////////////////////////////////////////////////// @ fops2 depends on !fops1 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier read.read_f; @@ // read fops use offset struct file_operations fops = { ... .read = read_f, ... +.llseek = default_llseek, /* read accesses f_pos */ }; @ fops3 depends on !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier write.write_f; @@ // write fops use offset struct file_operations fops = { ... .write = write_f, ... + .llseek = default_llseek, /* write accesses f_pos */ }; // Use noop_llseek if neither read nor write accesses f_pos /////////////////////////////////////////////////////////// @ fops4 depends on !fops1 && !fops2 && !fops3 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier read_no_fpos.read_f; identifier write_no_fpos.write_f; @@ // write fops use offset struct file_operations fops = { ... .write = write_f, .read = read_f, ... +.llseek = noop_llseek, /* read and write both use no f_pos */ }; @ depends on has_write && !has_read && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier write_no_fpos.write_f; @@ struct file_operations fops = { ... .write = write_f, ... +.llseek = noop_llseek, /* write uses no f_pos */ }; @ depends on has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier read_no_fpos.read_f; @@ struct file_operations fops = { ... .read = read_f, ... +.llseek = noop_llseek, /* read uses no f_pos */ }; @ depends on !has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; @@ struct file_operations fops = { ... +.llseek = noop_llseek, /* no read or write fn */ }; ===== End semantic patch ===== Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: Julia Lawall <julia@diku.dk> Cc: Christoph Hellwig <hch@infradead.org>
* dlm: fix ast ordering for user locksDavid Teigland2010-04-301-14/+74
| | | | | | | | | Commit 7fe2b3190b8b299409f13cf3a6f85c2bd371f8bb fixed possible misordering of completion asts (casts) and blocking asts (basts) for kernel locks. This patch does the same for locks taken by user space applications. Signed-off-by: David Teigland <teigland@redhat.com>
* 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>
* dlm: fix ordering of bast and castDavid Teigland2010-02-241-4/+6
| | | | | | | | | | | | | | | | | | | When both blocking and completion callbacks are queued for lock, the dlm would always deliver the completion callback (cast) first. In some cases the blocking callback (bast) is queued before the cast, though, and should be delivered first. This patch keeps track of the order in which they were queued and delivers them in that order. This patch also keeps track of the granted mode in the last cast and eliminates the following bast if the bast mode is compatible with the preceding cast mode. This happens when a remotely mastered lock is demoted, e.g. EX->NL, in which case the local node queues a cast immediately after sending the demote message. In this way a cast can be queued for a mode, e.g. NL, that makes an in-transit bast extraneous. Signed-off-by: David Teigland <teigland@redhat.com>
* dlm: always use GFP_NOFSDavid Teigland2009-11-301-6/+6
| | | | | | | | | | | | | | Replace all GFP_KERNEL and ls_allocation with GFP_NOFS. ls_allocation would be GFP_KERNEL for userland lockspaces and GFP_NOFS for file system lockspaces. It was discovered that any lockspaces on the system can affect all others by triggering memory reclaim in the file system which could in turn call back into the dlm to acquire locks, deadlocking dlm threads that were shared by all lockspaces, like dlm_recv. Signed-off-by: David Teigland <teigland@redhat.com>
* dlm: fix length calculation in compat codeDavid Teigland2009-03-111-9/+15
| | | | | | | | | | | | | Using offsetof() to calculate name length does not work because it does not produce consistent results with with structure packing. This caused memcpy to corrupt memory by copying 4 extra bytes off the end of the buffer on 64 bit kernels with 32 bit userspace (the only case where this 32/64 compat code is used). The fix is to calculate name length directly from the start instead of trying to derive it later using count and offsetof. Signed-off-by: David Teigland <teigland@redhat.com>
* dlm: improve how bast mode handlingDavid Teigland2008-12-231-1/+3
| | | | | | | | | | | The lkb bastmode value is set in the context of processing the lock, and read by the dlm_astd thread. Because it's accessed in these two separate contexts, the writing/reading ought to be done under a lock. This is simple to do by setting it and reading it when the lkb is added to and removed from dlm_astd's callback list which is properly locked. Signed-off-by: David Teigland <teigland@redhat.com>
* dlm: remove bklDavid Teigland2008-09-041-8/+1
| | | | | | BLK from recent pushdown is not needed. Signed-off-by: David Teigland <teigland@redhat.com>
* dlm: detect available userspace daemonDavid Teigland2008-08-281-1/+60
| | | | | | | | | | | | | | | If dlm_controld (the userspace daemon that controls the setup and recovery of the dlm) fails, the kernel should shut down the lockspaces in the kernel rather than leaving them running. This is detected by having dlm_controld hold a misc device open while running, and if the kernel detects a close while the daemon is still needed, it stops the lockspaces in the kernel. Knowing that the userspace daemon isn't running also allows the lockspace create/remove routines to avoid waiting on the daemon for join/leave operations. Signed-off-by: David Teigland <teigland@redhat.com>
* dlm: allow multiple lockspace createsDavid Teigland2008-08-281-21/+33
| | | | | | | | | | Add a count for lockspace create and release so that create can be called multiple times to use the lockspace from different places. Also add the new flag DLM_LSFL_NEWEXCL to create a lockspace with the previous behavior of returning -EEXIST if the lockspace already exists. Signed-off-by: David Teigland <teigland@redhat.com>
* dlm: add missing kfreesDavid Teigland2008-08-131-3/+7
| | | | | | | | A couple of unlikely error conditions were missing a kfree on the error exit path. Reported-by: Juha Leppanen <juha_motorsportcom@luukku.com> Signed-off-by: David Teigland <teigland@redhat.com>
* Merge branch 'for-linus' of ↵Linus Torvalds2008-07-281-1/+1
|\ | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/teigland/dlm * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/teigland/dlm: dlm: fix uninitialized variable for search_rsb_list callers dlm: release socket on error dlm: fix basts for granted CW waiting PR/CW dlm: check for null in device_write
| * dlm: check for null in device_writeMasatake YAMATO2008-07-141-1/+1
| | | | | | | | | | | | | | | | | | If `device_write' method is called via "dlm-control", file->private_data is NULL. (See ctl_device_open() in user.c. ) Through proc->flags is read. Signed-off-by: Masatake YAMATO <yamato@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
* | dlm-user: BKL pushdownArnd Bergmann2008-06-201-1/+8
|/ | | | Signed-off-by: Arnd Bergmann <arnd@arndb.de>
* dlm: add __init and __exit marks to init and exit functionsDenis Cheng2008-02-061-1/+1
| | | | | | | | it moves 365 bytes from .text to .init.text, and 30 bytes from .text to .exit.text, saves memory. Signed-off-by: Denis Cheng <crquan@gmail.com> Signed-off-by: David Teigland <teigland@redhat.com>
* dlm: eliminate astparam type castingDavid Teigland2008-02-061-5/+3
| | | | | | | Put lkb_astparam in a union with a dlm_user_args pointer to eliminate a lot of type casting. Signed-off-by: David Teigland <teigland@redhat.com>
* dlm: dlm/user.c input validation fixesAl Viro2008-02-041-11/+8
| | | | | | | | | a) in device_write(): add sentinel NUL byte, making sure that lspace.name will be NUL-terminated b) in compat_input() be keep it simple about the amounts of data we are copying. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: David Teigland <teigland@redhat.com>
* dlm: static initialization improvementsDenis Cheng2008-01-301-6/+7
| | | | | | | also change name_prefix from char pointer to char array. Signed-off-by: Denis Cheng <crquan@gmail.com> Signed-off-by: David Teigland <teigland@redhat.com>
* dlm: Sanity check namelen before copying itPatrick Caulfeld2008-01-301-3/+9
| | | | | | | | | | | | | The 32/64 compatibility code in the DLM does not check the validity of the lock name length passed into it, so it can easily overwrite memory if the value is rubbish (as early versions of libdlm can cause with unlock calls, it doesn't zero the field). This patch restricts the length of the name to the amount of data actually passed into the call. Signed-off-by: Patrick Caulfield <pcaulfie@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com>
* dlm: fix possible use-after-freeDavid Teigland2008-01-301-2/+2
| | | | | | | The dlm_put_lkb() can free the lkb and its associated ua structure, so we can't depend on using the ua struct after the put. Signed-off-by: David Teigland <teigland@redhat.com>
* Use helpers to obtain task pid in printksPavel Emelyanov2007-10-191-1/+1
| | | | | | | | | | | | | | | | The task_struct->pid member is going to be deprecated, so start using the helpers (task_pid_nr/task_pid_vnr/task_pid_nr_ns) in the kernel. The first thing to start with is the pid, printed to dmesg - in this case we may safely use task_pid_nr(). Besides, printks produce more (much more) than a half of all the explicit pid usage. [akpm@linux-foundation.org: git-drm went and changed lots of stuff] Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Cc: Dave Airlie <airlied@linux.ie> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [DLM] canceling deadlocked lockDavid Teigland2007-07-091-0/+25
| | | | | | | | | Add a function that can be used through libdlm by a system daemon to cancel another process's deadlocked lock. A completion ast with EDEADLK is returned to the process waiting for the lock. Signed-off-by: David Teigland <teigland@redhat.com> Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
* [DLM] timeout fixesDavid Teigland2007-07-091-19/+30
| | | | | | | | | | | | | | | | | | Various fixes related to the new timeout feature: - add_timeout() missed setting TIMEWARN flag on lkb's when the TIMEOUT flag was already set - clear_proc_locks should remove a dead process's locks from the timeout list - the end-of-life calculation for user locks needs to consider that ETIMEDOUT is equivalent to -DLM_ECANCEL - make initial default timewarn_cs config value visible in configfs - change bit position of TIMEOUT_CANCEL flag so it's not copied to a remote master node - set timestamp on remote lkb's so a lock dump will display the time they've been waiting Signed-off-by: David Teigland <teigland@redhat.com> Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
* [DLM] dlm_device interface changes [3/6]David Teigland2007-07-091-10/+43
| | | | | | | | | | | | | | | | | | | | Change the user/kernel device interface used by libdlm: - Add ability for userspace to check the version of the interface. libdlm can now adapt to different versions of the kernel interface. - Increase the size of the flags passed in a lock request so all possible flags can be used from userspace. - Add an opaque "xid" value for each lock. This "transaction id" will be used later to associate locks with each other during deadlock detection. - Add a "timeout" value for each lock. This is used along with the DLM_LKF_TIMEOUT flag. Also, remove a fragment of unused code in device_read(). This patch requires updating libdlm which is backward compatible with older kernels. Signed-off-by: David Teigland <teigland@redhat.com> Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
* [DLM] add lock timeouts and warnings [2/6]David Teigland2007-07-091-1/+1
| | | | | | | | | | | | | | | | | New features: lock timeouts and time warnings. If the DLM_LKF_TIMEOUT flag is set, then the request/conversion will be canceled after waiting the specified number of centiseconds (specified per lock). This feature is only available for locks requested through libdlm (can be enabled for kernel dlm users if there's a use for it.) If the new DLM_LSFL_TIMEWARN flag is set when creating the lockspace, then a warning message will be sent to userspace (using genetlink) after a request/conversion has been waiting for a given number of centiseconds (configurable per node). The time warnings will be used in the future to do deadlock detection in userspace. Signed-off-by: David Teigland <teigland@redhat.com> Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
* [DLM] Remove redundant assignmentPatrick Caulfield2007-05-011-2/+0
| | | | | | | This patch removes a redundant (and incorrect) assignment from compat_output Signed-Off-By: Patrick Caulfield <pcaulfie@redhat.com> Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
* [DLM] interface for purge (2/2)David Teigland2007-05-011-0/+28
| | | | | | | Add code to accept purge commands from userland. Signed-off-by: David Teigland <teigland@redhat.com> Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
* [DLM] overlapping cancel and unlockDavid Teigland2007-05-011-33/+44
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Full cancel and force-unlock support. In the past, cancel and force-unlock wouldn't work if there was another operation in progress on the lock. Now, both cancel and unlock-force can overlap an operation on a lock, meaning there may be 2 or 3 operations in progress on a lock in parallel. This support is important not only because cancel and force-unlock are explicit operations that an app can use, but both are used implicitly when a process exits while holding locks. Summary of changes: - add-to and remove-from waiters functions were rewritten to handle situations with more than one remote operation outstanding on a lock - validate_unlock_args detects when an overlapping cancel/unlock-force can be sent and when it needs to be delayed until a request/lookup reply is received - processing request/lookup replies detects when cancel/unlock-force occured during the op, and carries out the delayed cancel/unlock-force - manipulation of the "waiters" (remote operation) state of a lock moved under the standard rsb mutex that protects all the other lock state - the two recovery routines related to locks on the waiters list changed according to the way lkb's are now locked before accessing waiters state - waiters recovery detects when lkb's being recovered have overlapping cancel/unlock-force, and may not recover such locks - revert_lock (cancel) returns a value to distinguish cases where it did nothing vs cases where it actually did a cancel; the cancel completion ast should only be done when cancel did something - orphaned locks put on new list so they can be found later for purging - cancel must be called on a lock when making it an orphan - flag user locks (ENDOFLIFE) at the end of their useful life (to the application) so we can return an error for any further cancel/unlock-force - we weren't setting COMP/BAST ast flags if one was already set, so we'd lose either a completion or blocking ast - clear an unread bast on a lock that's become unlocked Signed-off-by: David Teigland <teigland@redhat.com> Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
* [DLM] Don't delete misc device if lockspace removal failsPatrick Caulfield2007-05-011-22/+36
| | | | | | | | | | | | | | | | Currently if the lockspace removal fails the misc device associated with a lockspace is left deleted. After that there is no way to access the orphaned lockspace from userland. This patch recreates the misc device if th dlm_release_lockspace fails. I believe this is better than attempting to remove the lockspace first because that leaves an unattached device lying around. The potential gap in which there is no access to the lockspace between removing the misc device and recreating it is acceptable ... after all the application is trying to remove it, and only new users of the lockspace will be affected. Signed-Off-By: Patrick Caulfield <pcaulfie@redhat.com> Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
* [DLM] fs/dlm/user.c should #include "user.h"Adrian Bunk2007-03-071-0/+1
| | | | | | | | Every file should include the headers containing the prototypes for it's global functions. Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
* [PATCH] mark struct file_operations const 6Arjan van de Ven2007-02-121-3/+3
| | | | | | | | | | | Many struct file_operations in the kernel can be "const". Marking them const moves these to the .rodata section, which avoids false sharing with potential dirty data. In addition it'll catch accidental writes at compile time to these shared resources. Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [DLM] fix user unlockingDavid Teigland2007-02-051-0/+9
| | | | | | | | | | | | | | When a user process exits, we clear all the locks it holds. There is a problem, though, with locks that the process had begun unlocking before it exited. We couldn't find the lkb's that were in the process of being unlocked remotely, to flag that they are DEAD. To solve this, we move lkb's being unlocked onto a new list in the per-process structure that tracks what locks the process is holding. We can then go through this list to flag the necessary lkb's when clearing locks for a process when it exits. Signed-off-by: David Teigland <teigland@redhat.com> Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
* [DLM] force removal of user lockspaceDavid Teigland2006-08-311-3/+6
| | | | | | | | | Check if the FORCEFREE flag has been provided from user space. If so, set the force option to dlm_release_lockspace() so that any remaining locks will be freed. Signed-off-by: David Teigland <teigland@redhat.com> Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
* [DLM] fix whitespace damageDavid Teigland2006-07-211-1/+1
| | | | | | | My previous dlm patch added trailing whitespace damage, fix that. Signed-off-by: David Teigland <teigland@redhat.com> Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
* [DLM] fix leaking user locksDavid Teigland2006-07-201-0/+16
| | | | | | | | User NOQUEUE lock requests to a remote node that failed with -EAGAIN were never being removed from a process's list of locks. Signed-off-by: David Teigland <teigland@redhat.com> Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
* [DLM] dlm: user locksDavid Teigland2006-07-131-0/+769
This changes the way the dlm handles user locks. The core dlm is now aware of user locks so they can be dealt with more efficiently. There is no more dlm_device module which previously managed its own duplicate copy of every user lock. Signed-off-by: Patrick Caulfield <pcaulfie@redhat.com> Signed-off-by: David Teigland <teigland@redhat.com> Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
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