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* ocfs2: Introduce the DOWN message to ocfs2_controlJoel Becker2008-04-18
| | | | | | | | When the control daemon sees a node go down, it sends a DOWN message through the ocfs2_control device. Signed-off-by: Joel Becker <joel.becker@oracle.com> Signed-off-by: Mark Fasheh <mfasheh@suse.com>
* ocfs2: Start the ocfs2_control handshake.Joel Becker2008-04-18
| | | | | | | | | | | | | When a control daemon opens the ocfs2_control device, it must perform a handshake to tell the filesystem it is something capable of monitoring cluster status. Only after the handshake is complete will the filesystem allow mounts. This is the first part of the handshake. The daemon reads all supported ocfs2_control protocols, then writes in the protocol it will use. Signed-off-by: Joel Becker <joel.becker@oracle.com> Signed-off-by: Mark Fasheh <mfasheh@suse.com>
* ocfs2: Add the ocfs2_control misc device.Joel Becker2008-04-18
| | | | | | | | The ocfs2_control misc device is how a userspace control daemon (controld) talks to the filesystem. Introduce the bare-bones filesystem ops. Signed-off-by: Joel Becker <joel.becker@oracle.com> Signed-off-by: Mark Fasheh <mfasheh@suse.com>
* ocfs2: Add the user stack module.Joel Becker2008-04-18
| | | | | | | | Add a skeleton for the stack_user module. It's just the barebones module code. Signed-off-by: Joel Becker <joel.becker@oracle.com> Signed-off-by: Mark Fasheh <mfasheh@suse.com>
* ocfs2: Add the 'cluster_stack' sysfs file.Joel Becker2008-04-18
| | | | | | | | | | | | | | | | | | Userspace can now query and specify the cluster stack in use via the /sys/fs/ocfs2/cluster_stack file. By default, it is 'o2cb', which is the classic stack. Thus, old tools that do not know how to modify this file will work just fine. The stack cannot be modified if there is a live filesystem. ocfs2_cluster_connect() now takes the expected cluster stack as an argument. This way, the filesystem and the stack glue ensure they are speaking to the same backend. If the stack is 'o2cb', the o2cb stack plugin is used. For any other value, the fsdlm stack plugin is selected. Signed-off-by: Joel Becker <joel.becker@oracle.com> Signed-off-by: Mark Fasheh <mfasheh@suse.com>
* ocfs2: Add the USERSPACE_STACK incompat bit.Joel Becker2008-04-18
| | | | | | | | | | | | | | | | | | The filesystem gains the USERSPACE_STACK incomat bit and the s_cluster_info field on the superblock. When a userspace stack is in use, the name of the stack is stored on-disk for mount-time verification. The "cluster_stack" option is added to mount(2) processing. The mount process needs to pass the matching stack name. If the passed name and the on-disk name do not match, the mount is failed. When using the classic o2cb stack, the incompat bit is *not* set and no mount option is used other than the usual heartbeat=local. Thus, the filesystem is compatible with older tools. Signed-off-by: Joel Becker <joel.becker@oracle.com> Signed-off-by: Mark Fasheh <mfasheh@suse.com>
* ocfs2: Create stack glue sysfs files.Joel Becker2008-04-18
| | | | | | | | | | | | Introduce a set of sysfs files that describe the current stack glue state. The files live under /sys/fs/ocfs2. The locking_protocol file displays the version of ocfs2's locking code. The loaded_cluster_plugins file displays all of the currently loaded stack plugins. When filesystems are mounted, the active_cluster_plugin file will display the plugin in use. Signed-off-by: Joel Becker <joel.becker@oracle.com> Signed-off-by: Mark Fasheh <mfasheh@suse.com>
* ocfs2: Break out stackglue into modules.Joel Becker2008-04-18
| | | | | | | | | | | | | | | | | | We define the ocfs2_stack_plugin structure to represent a stack driver. The o2cb stack code is split into stack_o2cb.c. This becomes the ocfs2_stack_o2cb.ko module. The stackglue generic functions are similarly split into the ocfs2_stackglue.ko module. This module now provides an interface to register drivers. The ocfs2_stack_o2cb driver registers itself. As part of this interface, ocfs2_stackglue can load drivers on demand. This is accomplished in ocfs2_cluster_connect(). ocfs2_cluster_disconnect() is now notified when a _hangup() is pending. If a hangup is pending, it will not release the driver module and will let _hangup() do that. Signed-off-by: Joel Becker <joel.becker@oracle.com>
* ocfs2: Create ocfs2_stack_operations and split out the o2cb stack.Joel Becker2008-04-18
| | | | | | | | | | | | | | | Define the ocfs2_stack_operations structure. Build o2cb_stack_ops from all of the o2cb-specific stack functions. Change the generic stack glue functions to call the stack_ops instead of the o2cb functions directly. The o2cb functions are moved to stack_o2cb.c. The headers are cleaned up to where only needed headers are included. In this code, stackglue.c and stack_o2cb.c refer to some shared extern variables. When they become modules, that will change. Signed-off-by: Joel Becker <joel.becker@oracle.com> Signed-off-by: Mark Fasheh <mfasheh@suse.com>
* ocfs2: Split o2cb code from generic stack functions.Joel Becker2008-04-18
| | | | | | | | | Split off the o2cb-specific funtionality from the generic stack glue calls. This is a precurser to wrapping the o2cb functionality in an operations vector. Signed-off-by: Joel Becker <joel.becker@oracle.com> Signed-off-by: Mark Fasheh <mfasheh@suse.com>
* ocfs2: Clean up stackglue initializationJoel Becker2008-04-18
| | | | | | | | The stack glue initialization function needs a better name so that it can be used cleanly when stackglue becomes a module. Signed-off-by: Joel Becker <joel.becker@oracle.com> Signed-off-by: Mark Fasheh <mfasheh@suse.com>
* ocfs2: Abstract out a debugging function for underlying dlms.Joel Becker2008-04-18
| | | | | | | | | | | dlmglue.c was still referencing a raw o2dlm lksb in one instance. Let's create a generic ocfs2_dlm_dump_lksb() function. This allows underlying DLMs to print whatever they want about their lock. We then move the o2dlm dump into stackglue.c where it belongs. Signed-off-by: Joel Becker <joel.becker@oracle.com> Signed-off-by: Mark Fasheh <mfasheh@suse.com>
* ocfs2: handle async EAGAIN from NOQUEUE requestDavid Teigland2008-04-18
| | | | | | | | | When using fsdlm, -EAGAIN is returned in the async callback for NOQUEUE requests. Fix up dlmglue to expect this. Signed-off-by: David Teigland <teigland@redhat.com> Signed-off-by: Joel Becker <joel.becker@oracle.com> Signed-off-by: Mark Fasheh <mfasheh@suse.com>
* ocfs2: Remove CANCELGRANT from the view of dlmglue.Joel Becker2008-04-18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | o2dlm has the non-standard behavior of providing a cancel callback (unlock_ast) even when the cancel has failed (the locking operation succeeded without canceling). This is called CANCELGRANT after the status code sent to the callback. fs/dlm does not provide this callback, so dlmglue must be changed to live without it. o2dlm_unlock_ast_wrapper() in stackglue now ignores CANCELGRANT calls. Because dlmglue no longer sees CANCELGRANT, ocfs2_unlock_ast() no longer needs to check for it. ocfs2_locking_ast() must catch that a cancel was tried and clear the cancel state. Making these changes opens up a locking race. dlmglue uses the the OCFS2_LOCK_BUSY flag to ensure only one thread is calling the dlm at any one time. But dlmglue must unlock the lockres before calling into the dlm. In the small window of time between unlocking the lockres and calling the dlm, the downconvert thread can try to cancel the lock. The downconvert thread is checking the OCFS2_LOCK_BUSY flag - it doesn't know that ocfs2_dlm_lock() has not yet been called. Because ocfs2_dlm_lock() has not yet been called, the cancel operation will just be a no-op. There's nothing to cancel. With CANCELGRANT, dlmglue uses the CANCELGRANT callback to clear up the cancel state. When it comes around again, it will retry the cancel. Eventually, the first thread will have called into ocfs2_dlm_lock(), and either the lock or the cancel will succeed. The downconvert thread can then do its downconvert. Without CANCELGRANT, there is nothing to clean up the cancellation state. The downconvert thread does not know to retry its operations. More importantly, the original lock may be blocking on the other node that is trying to cancel us. With neither able to make progress, the ast is never called and the cancellation state is never cleaned up that way. dlmglue is deadlocked. The OCFS2_LOCK_PENDING flag is introduced to remedy this window. It is set at the same time OCFS2_LOCK_BUSY is. Thus, the downconvert thread can check whether the lock is cancelable. If not, it just loops around to try again. Once ocfs2_dlm_lock() is called, the thread then clears OCFS2_LOCK_PENDING and wakes the downconvert thread. Now, if the downconvert thread finds the lock BUSY, it can safely try to cancel it. Whether the cancel works or not, the state will be properly set and the lock processing can continue. Signed-off-by: Joel Becker <joel.becker@oracle.com> Signed-off-by: Mark Fasheh <mfasheh@suse.com>
* ocfs2: Fill node number during cluster stack initMark Fasheh2008-04-18
| | | | | | | | | | | | | It doesn't make sense to query for a node number before connecting to the cluster stack. This should be safe to do because node_num is only just printed, and we're actually only moving the setting of node num a small amount further in the mount process. [ Disconnect when node query fails -- Joel ] Reviewed-by: Joel Becker <joel.becker@oracle.com> Signed-off-by: Mark Fasheh <mfasheh@suse.com>
* ocfs2: Move o2hb functionality into the stack glue.Joel Becker2008-04-18
| | | | | | | | | | | | | | | | | The last bit of classic stack used directly in ocfs2 code is o2hb. Specifically, the check for heartbeat during mount and the call to ocfs2_hb_ctl during unmount. We create an extra API, ocfs2_cluster_hangup(), to encapsulate the call to ocfs2_hb_ctl. Other stacks will just leave hangup() empty. The check for heartbeat is moved into ocfs2_cluster_connect(). It will be matched by a similar check for other stacks. With this change, only stackglue.c includes cluster/ headers. Signed-off-by: Joel Becker <joel.becker@oracle.com> Signed-off-by: Mark Fasheh <mfasheh@suse.com>
* ocfs2: Abstract out node number queries.Joel Becker2008-04-18
| | | | | | | | | | | | | | | | | ocfs2 asks the cluster stack for the local node's node number for two reasons; to fill the slot map and to print it. While the slot map isn't necessary for userspace cluster stacks, the printing is very nice for debugging. Thus we add ocfs2_cluster_this_node() as a generic API to get this value. It is anticipated that the slot map will not be used under a userspace cluster stack, so validity checks of the node num only need to exist in the slot map code. Otherwise, it just gets used and printed as an opaque value. [ Fixed up some "int" versus "unsigned int" issues and made osb->node_num truly opaque. --Mark ] Signed-off-by: Joel Becker <joel.becker@oracle.com> Signed-off-by: Mark Fasheh <mfasheh@suse.com>
* ocfs2: Introduce the new ocfs2_cluster_connect/disconnect() API.Joel Becker2008-04-18
| | | | | | | | | | | | | | | | | | | | | | | | This step introduces a cluster stack agnostic API for initializing and exiting. fs/ocfs2/dlmglue.c no longer uses o2cb/o2dlm knowledge to connect to the stack. It is all handled in stackglue.c. heartbeat.c no longer needs to know how it gets called. ocfs2_do_node_down() is now a clean recovery trigger. The big gotcha is the ordering of initializations and de-initializations done underneath ocfs2_cluster_connect(). ocfs2_dlm_init() used to do all o2dlm initialization in one block. Thus, the o2dlm functionality of ocfs2_cluster_connect() is very straightforward. ocfs2_dlm_shutdown(), however, did a few things between de-registration of the eviction callback and actually shutting down the domain. Now de-registration and shutdown of the domain are wrapped within the single ocfs2_cluster_disconnect() call. I've checked the code paths to make sure we can safely tear down things in ocfs2_dlm_shutdown() before calling ocfs2_cluster_disconnect(). The filesystem has already set itself to ignore the callback. Signed-off-by: Joel Becker <joel.becker@oracle.com> Signed-off-by: Mark Fasheh <mfasheh@suse.com>
* ocfs2: Create the lock status block union.Joel Becker2008-04-18
| | | | | | | | | | | | Wrap the lock status block (lksb) in a union. Later we will add a union element for the fs/dlm lksb. Create accessors for the status and lvb fields. Other than a debugging function, dlmglue.c does not directly reference the o2dlm locking path anymore. Signed-off-by: Joel Becker <joel.becker@oracle.com> Signed-off-by: Mark Fasheh <mfasheh@suse.com>
* ocfs2: Use -errno instead of dlm_status for ocfs2_dlm_lock/unlock() API.Joel Becker2008-04-18
| | | | | | | | | | | | | Change the ocfs2_dlm_lock/unlock() functions to return -errno values. This is the first step towards elminiating dlm_status in fs/ocfs2/dlmglue.c. The change also passes -errno values to ->unlock_ast(). [ Fix a return code in dlmglue.c and change the error translation table into an array of ints. --Mark ] Signed-off-by: Joel Becker <joel.becker@oracle.com> Signed-off-by: Mark Fasheh <mfasheh@suse.com>
* ocfs2: Use global DLM_ constants in generic code.Joel Becker2008-04-18
| | | | | | | | The ocfs2 generic code should use the values in <linux/dlmconstants.h>. stackglue.c will convert them to o2dlm values. Signed-off-by: Joel Becker <joel.becker@oracle.com> Signed-off-by: Mark Fasheh <mfasheh@suse.com>
* ocfs2: Separate out dlm lock functions.Joel Becker2008-04-18
| | | | | | | | | | | This is the first in a series of patches to isolate ocfs2 from the underlying cluster stack. Here we wrap the dlm locking functions with ocfs2-specific calls. Because ocfs2 always uses the same dlm lock status callbacks, we can eliminate the callbacks from the filesystem visible functions. Signed-off-by: Joel Becker <joel.becker@oracle.com> Signed-off-by: Mark Fasheh <mfasheh@suse.com>
* ocfs2: New slot map formatJoel Becker2008-04-18
| | | | | | | | | | | | | | | The old slot map had a few limitations: - It was limited to one block, so the maximum slot count was 255. - Each slot was signed 16bits, limiting node numbers to INT16_MAX. - An empty slot was marked by the magic 0xFFFF (-1). The new slot map format provides 32bit node numbers (UINT32_MAX), a separate space to mark a slot in use, and extra room to grow. The slot map is now bounded by i_size, not a block. Signed-off-by: Joel Becker <joel.becker@oracle.com> Signed-off-by: Mark Fasheh <mfasheh@suse.com>
* ocfs2: Define the contents of the slot_map file.Joel Becker2008-04-18
| | | | | | | | The slot map file is merely an array of __le16. Wrap it in a structure for cleaner reference. Signed-off-by: Joel Becker <joel.becker@oracle.com> Signed-off-by: Mark Fasheh <mfasheh@suse.com>
* ocfs2: De-magic the in-memory slot map.Joel Becker2008-04-18
| | | | | | | | | | | | | | | The in-memory slot map uses the same magic as the on-disk one. There is a special value to mark a slot as invalid. It relies on the size of certain types and so on. Write a new in-memory map that keeps validity as a separate field. Outside of the I/O functions, OCFS2_INVALID_SLOT now means what it is supposed to. It also is no longer tied to the type size. This also means that only the I/O functions refer to 16bit quantities. Signed-off-by: Joel Becker <joel.becker@oracle.com> Signed-off-by: Mark Fasheh <mfasheh@suse.com>
* ocfs2: slot_map I/O based on max_slots.Joel Becker2008-04-18
| | | | | | | | The slot map code assumed a slot_map file has one block allocated. This changes the code to I/O as many blocks as will cover max_slots. Signed-off-by: Joel Becker <joel.becker@oracle.com> Signed-off-by: Mark Fasheh <mfasheh@suse.com>
* ocfs2: Change the recovery map to an array of node numbers.Joel Becker2008-04-18
| | | | | | | | | | | | | | | | | | | | | | | | | | The old recovery map was a bitmap of node numbers. This was sufficient for the maximum node number of 254. Going forward, we want node numbers to be UINT32. Thus, we need a new recovery map. Note that we can't keep track of slots here. We must write down the node number to recovery *before* we get the locks needed to convert a node number into a slot number. The recovery map is now an array of unsigned ints, max_slots in size. It moves to journal.c with the rest of recovery. Because it needs to be initialized, we move all of recovery initialization into a new function, ocfs2_recovery_init(). This actually cleans up ocfs2_initialize_super() a little as well. Following on, recovery cleaup becomes part of ocfs2_recovery_exit(). A number of node map functions are rendered obsolete and are removed. Finally, waiting on recovery is wrapped in a function rather than naked checks on the recovery_event. This is a cleanup from Mark. Signed-off-by: Joel Becker <joel.becker@oracle.com> Signed-off-by: Mark Fasheh <mfasheh@suse.com>
* ocfs2: Make ocfs2_slot_info private.Joel Becker2008-04-18
| | | | | | | | | Just use osb_lock around the ocfs2_slot_info data. This allows us to take the ocfs2_slot_info structure private in slot_info.c. All access is now via accessors. Signed-off-by: Joel Becker <joel.becker@oracle.com> Signed-off-by: Mark Fasheh <mfasheh@suse.com>
* ocfs2: Move slot map access into slot_map.cMark Fasheh2008-04-18
| | | | | | | | | journal.c and dlmglue.c would refresh the slot map by hand. Instead, have the update and clear functions do the work inside slot_map.c. The eventual result is to make ocfs2_slot_info defined privately in slot_map.c Signed-off-by: Joel Becker <joel.becker@oracle.com> Signed-off-by: Mark Fasheh <mfasheh@suse.com>
* AFS: Do not describe debug parameters with their valuePaul Bolle2008-04-16
| | | | | | | | Describe debug parameters with their names (and not their values). Signed-off-by: Paul Bolle <pebolle@tiscali.nl> Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* vfs: fix possible deadlock in ext2, ext3, ext4 when using xattrsJan Kara2008-04-15
| | | | | | | | | | | | | | mb_cache_entry_alloc() was allocating cache entries with GFP_KERNEL. But filesystems are calling this function while holding xattr_sem so possible recursion into the fs violates locking ordering of xattr_sem and transaction start / i_mutex for ext2-4. Change mb_cache_entry_alloc() so that filesystems can specify desired gfp mask and use GFP_NOFS from all of them. Signed-off-by: Jan Kara <jack@suse.cz> Reported-by: Dave Jones <davej@redhat.com> Cc: <linux-ext4@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* JFFS2 Fix of panics caused by wrong condition for hole frag creation in ↵Alexey Korolev2008-04-14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | write_begin This fixes a regression introduced in commit 205c109a7a96d9a3d8ffe64c4068b70811fef5e8 when switching to write_begin/write_end operations in JFFS2. The page offset is miscalculated, leading to corruption of the fragment lists and subsequently to memory corruption and panics. [ Side note: the bug is a fairly direct result of the naming. Nick was likely misled by the use of "offs", since we tend to use the notion of "offset" not as an absolute position, but as an offset _within_ a page or allocation. Alternatively, a "pgoff_t" is a page index, but not a byte offset - our VM naming can be a bit confusing. So in this case, a VM person would likely have called this a "pos", not an "offs", or perhaps talked about byte offsets rather than page offsets (since it's counted in bytes, not pages). - Linus ] Signed-off-by: Alexey Korolev <akorolev@infradead.org> Signed-off-by: Vasiliy Leonenko <vasiliy.leonenko@mail.ru> Signed-off-by: David Woodhouse <dwmw2@infradead.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* locks: fix possible infinite loop in fcntl(F_SETLKW) over nfsJ. Bruce Fields2008-04-14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Miklos Szeredi found the bug: "Basically what happens is that on the server nlm_fopen() calls nfsd_open() which returns -EACCES, to which nlm_fopen() returns NLM_LCK_DENIED. "On the client this will turn into a -EAGAIN (nlm_stat_to_errno()), which in will cause fcntl_setlk() to retry forever." So, for example, opening a file on an nfs filesystem, changing permissions to forbid further access, then trying to lock the file, could result in an infinite loop. And Trond Myklebust identified the culprit, from Marc Eshel and I: 7723ec9777d9832849b76475b1a21a2872a40d20 "locks: factor out generic/filesystem switch from setlock code" That commit claimed to just be reshuffling code, but actually introduced a behavioral change by calling the lock method repeatedly as long as it returned -EAGAIN. We assumed this would be safe, since we assumed a lock of type SETLKW would only return with either success or an error other than -EAGAIN. However, nfs does can in fact return -EAGAIN in this situation, and independently of whether that behavior is correct or not, we don't actually need this change, and it seems far safer not to depend on such assumptions about the filesystem's ->lock method. Therefore, revert the problematic part of the original commit. This leaves vfs_lock_file() and its other callers unchanged, while returning fcntl_setlk and fcntl_setlk64 to their former behavior. Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu> Tested-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Trond Myklebust <trond.myklebust@fys.uio.no> Cc: Marc Eshel <eshel@almaden.ibm.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge branch 'docs' of git://git.lwn.net/linux-2.6Linus Torvalds2008-04-11
|\ | | | | | | | | | | | | | | | | | | | | | | | | * 'docs' of git://git.lwn.net/linux-2.6: Add additional examples in Documentation/spinlocks.txt Move sched-rt-group.txt to scheduler/ Documentation: move rpc-cache.txt to filesystems/ Documentation: move nfsroot.txt to filesystems/ Spell out behavior of atomic_dec_and_lock() in kerneldoc Fix a typo in highres.txt Fixes to the seq_file document Fill out information on patch tags in SubmittingPatches Add the seq_file documentation
| * Documentation: move nfsroot.txt to filesystems/J. Bruce Fields2008-04-11
| | | | | | | | | | | | | | | | Documentation/ is a little large, and filesystems/ seems an obvious place for this file. Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
* | signalfd: fix for incorrect SI_QUEUE user data reportingDavide Libenzi2008-04-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Michael Kerrisk found out that signalfd was not reporting back user data pushed using sigqueue: http://groups.google.com/group/linux.kernel/msg/9397cab8551e3123 The following patch makes signalfd report back the ssi_ptr and ssi_int members of the signalfd_siginfo structure. Signed-off-by: Davide Libenzi <davidel@xmailserver.org> Acked-by: Michael Kerrisk <mtk.manpages@googlemail.com> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | eventfd/kaio integration fixDavide Libenzi2008-04-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Jeff Roberson discovered a race when using kaio eventfd based notifications. When it occurs it can lead tomissed wakeups and hung userspace. This patch fixes the race by moving the notification inside the spinlocked section of kaio. The operation is safe since eventfd spinlock and kaio one are unrelated. Signed-off-by: Davide Libenzi <davidel@xmailserver.org> Cc: Zach Brown <zach.brown@oracle.com> Cc: Jeff Roberson <jroberson@chesapeake.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | asmlinkage_protect sys_io_geteventsRoland McGrath2008-04-10
| | | | | | | | | | | | | | | | | | | | | | Use asmlinkage_protect in sys_io_getevents, because GCC for i386 with CONFIG_FRAME_POINTER=n can decide to clobber an argument word on the stack, i.e. the user struct pt_regs. Here the problem is not a tail call, but just the compiler's use of the stack when it inlines and optimizes the body of the called function. This seems to avoid it. Signed-off-by: Roland McGrath <roland@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | asmlinkage_protect replaces prevent_tail_callRoland McGrath2008-04-10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The prevent_tail_call() macro works around the problem of the compiler clobbering argument words on the stack, which for asmlinkage functions is the caller's (user's) struct pt_regs. The tail/sibling-call optimization is not the only way that the compiler can decide to use stack argument words as scratch space, which we have to prevent. Other optimizations can do it too. Until we have new compiler support to make "asmlinkage" binding on the compiler's own use of the stack argument frame, we have work around all the manifestations of this issue that crop up. More cases seem to be prevented by also keeping the incoming argument variables live at the end of the function. This makes their original stack slots attractive places to leave those variables, so the compiler tends not clobber them for something else. It's still no guarantee, but it handles some observed cases that prevent_tail_call() did not. Signed-off-by: Roland McGrath <roland@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | Merge branch 'for-linus' of git://oss.sgi.com:8090/xfs/xfs-2.6Linus Torvalds2008-04-10
|\ \ | | | | | | | | | | | | | | | | | | * 'for-linus' of git://oss.sgi.com:8090/xfs/xfs-2.6: [XFS] Ensure "both" features2 slots are consistent [XFS] Fix superblock features2 field alignment problem [XFS] remove shouting-indirection macros from xfs_sb.h
| * | [XFS] Ensure "both" features2 slots are consistentEric Sandeen2008-04-10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since older kernels may look in the sb_bad_features2 slot for flags, rather than zeroing it out on fixup, we should make it equal to the sb_features2 value. Also, if the ATTR2 flag was not found prior to features2 fixup, it was not set in the mount flags, so re-check after the fixup so that the current session will use the feature. Also fix up the comments to reflect these changes. SGI-PV: 980085 SGI-Modid: xfs-linux-melb:xfs-kern:30778a Signed-off-by: Eric Sandeen <sandeen@sandeen.net> Signed-off-by: David Chinner <dgc@sgi.com> Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
| * | [XFS] Fix superblock features2 field alignment problemDavid Chinner2008-04-10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Due to the xfs_dsb_t structure not being 64 bit aligned, the last field of the on-disk superblock can vary in location This causes problems when the filesystem gets moved to a different platform, or there is a 32 bit userspace and 64 bit kernel. This patch detects the defect at mount time, logs a warning such as: XFS: correcting sb_features alignment problem in dmesg and corrects the problem so that everything is OK. it also blacklists the bad field in the superblock so it does not get used for something else later on. SGI-PV: 977636 SGI-Modid: xfs-linux-melb:xfs-kern:30539a Signed-off-by: David Chinner <dgc@sgi.com> Signed-off-by: Christoph Hellwig <hch@infradead.org> Signed-off-by: Eric Sandeen <sandeen@sandeen.net> Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
| * | [XFS] remove shouting-indirection macros from xfs_sb.hEric Sandeen2008-04-10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Remove macro-to-small-function indirection from xfs_sb.h, and remove some which are completely unused. SGI-PV: 976035 SGI-Modid: xfs-linux-melb:xfs-kern:30528a Signed-off-by: Eric Sandeen <sandeen@sandeen.net> Signed-off-by: Donald Douwsma <donaldd@sgi.com> Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
* | | Merge branch 'for-linus' of git://git.kernel.dk/linux-2.6-blockLinus Torvalds2008-04-10
|\ \ \ | | | | | | | | | | | | | | | | | | | | * 'for-linus' of git://git.kernel.dk/linux-2.6-block: cfq-iosched: do not leak ioc_data across iosched switches splice: fix infinite loop in generic_file_splice_read()
| * | | splice: fix infinite loop in generic_file_splice_read()Jens Axboe2008-04-10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There's a quirky loop in generic_file_splice_read() that could go on indefinitely, if the file splice returns 0 permanently (and not just as a temporary condition). Get rid of the loop and pass back -EAGAIN correctly from __generic_file_splice_read(), so we handle that condition properly as well. Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* | | | HFS+: fix unlink of linksRoman Zippel2008-04-10
|/ / / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Some time ago while attempting to handle invalid link counts, I botched the unlink of links itself, so this patch fixes this now correctly, so that only the link count of nodes that don't point to links is ignored. Thanks to Vlado Plaga <rechner@vlado-do.de> to notify me of this problem. Signed-off-by: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | fix bug - executing FDPIC ELF on NFS mount triggers BUG() at ↵Bryan Wu2008-04-08
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | mm/nommu.c:862:/do_mmap_private() NFS needs a NOMMU version mmap function to support uClinux on NOMMU machine http://blackfin.uclinux.org/gf/project/uclinux-dist/tracker/?action=TrackerItemEdit&tracker_id=141&tracker_item_id=3992 Signed-off-by: Bryan Wu <cooloney@kernel.org> Cc: Mike Frysinger <vapier.adi@gmail.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* | | NFS: initialize flags field in nfs_open_contextJeff Layton2008-04-08
|/ / | | | | | | | | | | | | | | | | | | The nfs_open_context struct had a "flags" field added recently, but the allocator isn't initializing it. It also looks like the allocator isn't initializing the mode or list either, but they seem to be overwritten by the caller, so that's less of an issue. Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* | Be more careful about marking buffers dirtyLinus Torvalds2008-04-04
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Mikulas Patocka noted that the optimization where we check if a buffer was already dirty (and we avoid re-dirtying it) was not really SMP-safe. Since the read of the old status was not synchronized with anything, an aggressive CPU re-ordering of memory accesses might have moved that read up to before the data was even written to the buffer, and another CPU that cleaned it again, causing the newly dirty state to never actually hit the disk. Admittedly this would probably never trigger in practice, but it's still wrong. Mikulas sent a patch that fixed the problem, but I dislike the subtlety of the whole optimization, so this is an alternate fix that is more explicit about the particular SMP ordering for the optimization, and separates out the speculative reads of the buffer state into its own conditional (and makes the memory barrier only happen if we are likely to actually hit the optimized case in the first place). I considered removing the optimization entirely, but Andrew argued for it's continued existence. I'm a push-over. Cc: Mikulas Patocka <mikulas@artax.karlin.mff.cuni.cz> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | afs: remove smp_prcessor_id() from debug macroSven Schnelle2008-04-03
| | | | | | | | | | | | Signed-off-by: Sven Schnelle <svens@stackframe.org> Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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