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2013-12-20IB/uverbs: New macro to set pointers to NULL if length is 0 in INIT_UDATA()Roland Dreier1-0/+8
Trying to have a ternary operator to choose between NULL (or 0) and the real pointer value in invocations leads to an impossible choice between a sparse error about a literal 0 used as a NULL pointer, and a gcc warning about "pointer/integer type mismatch in conditional expression." Rather than clutter the source with more casts, move the ternary operator into a new INIT_UDATA_BUF_OR_NULL() macro, which makes it easier to use and simplifies its callers. Reported-by: Yann Droneaud <ydroneaud@opteya.com> Signed-off-by: Roland Dreier <roland@purestorage.com>
2013-12-16IB/core: const'ify inbuf in struct ib_udataYann Droneaud1-1/+1
Userspace input buffer is not modified by kernel, so it can be 'const'. This is also a prerequisite to remove the implicit cast from INIT_UDATA(). Link: http://marc.info/?i=cover.1386798254.git.ydroneaud@opteya.com> Signed-off-by: Yann Droneaud <ydroneaud@opteya.com> Signed-off-by: Roland Dreier <roland@purestorage.com>
2013-11-17IB/core: Re-enable create_flow/destroy_flow uverbsMatan Barak1-4/+0
This commit reverts commit 7afbddfae993 ("IB/core: Temporarily disable create_flow/destroy_flow uverbs"). Since the uverbs extensions functionality was experimental for v3.12, this patch re-enables the support for them and flow-steering for v3.13. Signed-off-by: Matan Barak <matanb@mellanox.com> Signed-off-by: Roland Dreier <roland@purestorage.com>
2013-11-17IB/core: extended command: an improved infrastructure for uverbs commandsYann Droneaud1-2/+18
Commit 400dbc96583f ("IB/core: Infrastructure for extensible uverbs commands") added an infrastructure for extensible uverbs commands while later commit 436f2ad05a0b ("IB/core: Export ib_create/destroy_flow through uverbs") exported ib_create_flow()/ib_destroy_flow() functions using this new infrastructure. According to the commit 400dbc96583f, the purpose of this infrastructure is to support passing around provider (eg. hardware) specific buffers when userspace issue commands to the kernel, so that it would be possible to extend uverbs (eg. core) buffers independently from the provider buffers. But the new kernel command function prototypes were not modified to take advantage of this extension. This issue was exposed by Roland Dreier in a previous review[1]. So the following patch is an attempt to a revised extensible command infrastructure. This improved extensible command infrastructure distinguish between core (eg. legacy)'s command/response buffers from provider (eg. hardware)'s command/response buffers: each extended command implementing function is given a struct ib_udata to hold core (eg. uverbs) input and output buffers, and another struct ib_udata to hold the hw (eg. provider) input and output buffers. Having those buffers identified separately make it easier to increase one buffer to support extension without having to add some code to guess the exact size of each command/response parts: This should make the extended functions more reliable. Additionally, instead of relying on command identifier being greater than IB_USER_VERBS_CMD_THRESHOLD, the proposed infrastructure rely on unused bits in command field: on the 32 bits provided by command field, only 6 bits are really needed to encode the identifier of commands currently supported by the kernel. (Even using only 6 bits leaves room for about 23 new commands). So this patch makes use of some high order bits in command field to store flags, leaving enough room for more command identifiers than one will ever need (eg. 256). The new flags are used to specify if the command should be processed as an extended one or a legacy one. While designing the new command format, care was taken to make usage of flags itself extensible. Using high order bits of the commands field ensure that newer libibverbs on older kernel will properly fail when trying to call extended commands. On the other hand, older libibverbs on newer kernel will never be able to issue calls to extended commands. The extended command header includes the optional response pointer so that output buffer length and output buffer pointer are located together in the command, allowing proper parameters checking. This should make implementing functions easier and safer. Additionally the extended header ensure 64bits alignment, while making all sizes multiple of 8 bytes, extending the maximum buffer size: legacy extended Maximum command buffer: 256KBytes 1024KBytes (512KBytes + 512KBytes) Maximum response buffer: 256KBytes 1024KBytes (512KBytes + 512KBytes) For the purpose of doing proper buffer size accounting, the headers size are no more taken in account in "in_words". One of the odds of the current extensible infrastructure, reading twice the "legacy" command header, is fixed by removing the "legacy" command header from the extended command header: they are processed as two different parts of the command: memory is read once and information are not duplicated: it's making clear that's an extended command scheme and not a different command scheme. The proposed scheme will format input (command) and output (response) buffers this way: - command: legacy header + extended header + command data (core + hw): +----------------------------------------+ | flags | 00 00 | command | | in_words | out_words | +----------------------------------------+ | response | | response | | provider_in_words | provider_out_words | | padding | +----------------------------------------+ | | . <uverbs input> . . (in_words * 8) . | | +----------------------------------------+ | | . <provider input> . . (provider_in_words * 8) . | | +----------------------------------------+ - response, if present: +----------------------------------------+ | | . <uverbs output space> . . (out_words * 8) . | | +----------------------------------------+ | | . <provider output space> . . (provider_out_words * 8) . | | +----------------------------------------+ The overall design is to ensure that the extensible infrastructure is itself extensible while begin more reliable with more input and bound checking. Note: The unused field in the extended header would be perfect candidate to hold the command "comp_mask" (eg. bit field used to handle compatibility). This was suggested by Roland Dreier in a previous review[2]. But "comp_mask" field is likely to be present in the uverb input and/or provider input, likewise for the response, as noted by Matan Barak[3], so it doesn't make sense to put "comp_mask" in the header. [1]: http://marc.info/?i=CAL1RGDWxmM17W2o_era24A-TTDeKyoL6u3NRu_=t_dhV_ZA9MA@mail.gmail.com [2]: http://marc.info/?i=CAL1RGDXJtrc849M6_XNZT5xO1+ybKtLWGq6yg6LhoSsKpsmkYA@mail.gmail.com [3]: http://marc.info/?i=525C1149.6000701@mellanox.com Signed-off-by: Yann Droneaud <ydroneaud@opteya.com> Link: http://marc.info/?i=cover.1383773832.git.ydroneaud@opteya.com [ Convert "ret ? ret : 0" to the equivalent "ret". - Roland ] Signed-off-by: Roland Dreier <roland@purestorage.com>
2013-11-17IB/core: Remove ib_uverbs_flow_spec structure from userspaceYann Droneaud1-0/+16
The structure holding any types of flow_spec is of no use to userspace. It would be wrong for userspace to do: struct ib_uverbs_flow_spec flow_spec; flow_spec.type = IB_FLOW_SPEC_TCP; flow_spec.size = sizeof(flow_spec); Instead, userspace should use the dedicated flow_spec structure for - Ethernet : struct ib_uverbs_flow_spec_eth, - IPv4 : struct ib_uverbs_flow_spec_ipv4, - TCP/UDP : struct ib_uverbs_flow_spec_tcp_udp. In other words, struct ib_uverbs_flow_spec is a "virtual" data structure that can only be use by the kernel as an alias to the other. Signed-off-by: Yann Droneaud <ydroneaud@opteya.com> Link: http://marc.info/?i=cover.1383773832.git.ydroneaud@opteya.com Signed-off-by: Roland Dreier <roland@purestorage.com>
2013-10-21IB/core: Temporarily disable create_flow/destroy_flow uverbsYann Droneaud1-0/+2
The create_flow/destroy_flow uverbs and the associated extensions to the user-kernel verbs ABI are under review and are too experimental to freeze at this point. So userspace is not exposed to experimental features and an uinstable ABI, temporarily disable this for v3.12 (with a Kconfig option behind staging to reenable it if desired). The feature will be enabled after proper cleanup for v3.13. Signed-off-by: Yann Droneaud <ydroneaud@opteya.com> Link: http://marc.info/?i=cover.1381351016.git.ydroneaud@opteya.com Link: http://marc.info/?i=cover.1381177342.git.ydroneaud@opteya.com [ Add a Kconfig option to reenable these verbs. - Roland ] Signed-off-by: Roland Dreier <roland@purestorage.com>
2013-09-03Merge branches 'cxgb4', 'flowsteer', 'ipoib', 'iser', 'mlx4', 'ocrdma' and 'qib' into for-nextRoland Dreier1-0/+4
2013-08-28IB/core: Export ib_create/destroy_flow through uverbsHadar Hen Zion1-0/+3
Implement ib_uverbs_create_flow() and ib_uverbs_destroy_flow() to support flow steering for user space applications. Signed-off-by: Hadar Hen Zion <hadarh@mellanox.com> Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com> Signed-off-by: Roland Dreier <roland@purestorage.com>
2013-08-13IB/core: Fixes to XRC reference counting in uverbsYishai Hadas1-0/+1
Added reference counting mechanism for XRC target QPs between ib_uqp_object and its ib_uxrcd_object. This prevents closing an XRC domain that is still attached to a QP. In addition, add missing code in ib_uverbs_destroy_srq() to handle ib_uxrcd_object reference counting correctly when destroying an xsrq. Signed-off-by: Yishai Hadas <yishaih@mellanox.com> Signed-off-by: Jack Morgenstein <jackm@dev.mellanox.co.il> Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com> Signed-off-by: Roland Dreier <roland@purestorage.com>
2013-02-21IB/uverbs: Implement memory windows support in uverbsShani Michaeli1-0/+2
The existing user/kernel uverbs API has IB_USER_VERBS_CMD_ALLOC/DEALLOC_MW. Implement these calls, along with destroying user memory windows during process cleanup. Signed-off-by: Haggai Eran <haggaie@mellanox.com> Signed-off-by: Shani Michaeli <shanim@mellanox.com> Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com> Signed-off-by: Roland Dreier <roland@purestorage.com>
2011-10-13RDMA/uverbs: Export ib_open_qp() capability to user spaceSean Hefty1-0/+1
Allow processes that share the same XRC domain to open an existing shareable QP. This permits those processes to receive events on the shared QP and transfer ownership, so that any process may modify the QP. The latter allows the creating process to exit, while a remaining process can still transition it for path migration purposes. Signed-off-by: Sean Hefty <sean.hefty@intel.com> Signed-off-by: Roland Dreier <roland@purestorage.com>
2011-10-13RDMA/uverbs: Export XRC SRQs to user spaceSean Hefty1-0/+6
We require additional information to create XRC SRQs than we can exchange using the existing create SRQ ABI. Provide an enhanced create ABI for extended SRQ types. Based on patches by Jack Morgenstein <jackm@dev.mellanox.co.il> and Roland Dreier <roland@purestorage.com> Signed-off-by: Sean Hefty <sean.hefty@intel.com> Signed-off-by: Roland Dreier <roland@purestorage.com>
2011-10-13RDMA/uverbs: Export XRC domains to user spaceSean Hefty1-0/+11
Allow user space to create XRC domains. Because XRCDs are expected to be shared among multiple processes, we use inodes to identify an XRCD. Based on patches by Jack Morgenstein <jackm@dev.mellanox.co.il> Signed-off-by: Sean Hefty <sean.hefty@intel.com> Signed-off-by: Roland Dreier <roland@purestorage.com>
2010-03-04Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6Linus Torvalds1-1/+1
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6: (52 commits) init: Open /dev/console from rootfs mqueue: fix typo "failues" -> "failures" mqueue: only set error codes if they are really necessary mqueue: simplify do_open() error handling mqueue: apply mathematics distributivity on mq_bytes calculation mqueue: remove unneeded info->messages initialization mqueue: fix mq_open() file descriptor leak on user-space processes fix race in d_splice_alias() set S_DEAD on unlink() and non-directory rename() victims vfs: add NOFOLLOW flag to umount(2) get rid of ->mnt_parent in tomoyo/realpath hppfs can use existing proc_mnt, no need for do_kern_mount() in there Mirror MS_KERNMOUNT in ->mnt_flags get rid of useless vfsmount_lock use in put_mnt_ns() Take vfsmount_lock to fs/internal.h get rid of insanity with namespace roots in tomoyo take check for new events in namespace (guts of mounts_poll()) to namespace.c Don't mess with generic_permission() under ->d_lock in hpfs sanitize const/signedness for udf nilfs: sanitize const/signedness in dealing with ->d_name.name ... Fix up fairly trivial (famous last words...) conflicts in drivers/infiniband/core/uverbs_main.c and security/tomoyo/realpath.c
2010-03-03switch infiniband uverbs to anon_inodesAl Viro1-1/+1
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-02-24IB/uverbs: Pack struct ib_uverbs_event_file tighterAlexander Chiang1-2/+2
Eliminate some padding in the structure by rearranging the members. sizeof(struct ib_uverbs_event_file) is now 72 bytes (from 80) and more members now fit in the first cacheline. Signed-off-by: Alex Chiang <achiang@hp.com> Signed-off-by: Roland Dreier <rolandd@cisco.com>
2010-02-24IB/uverbs: Convert *cdev to cdev in struct ib_uverbs_deviceAlexander Chiang1-3/+4
Instead of storing a pointer to a cdev, embed the entire struct cdev. This change allows us to use the container_of() macro in ib_uverbs_open() in a future patch. This change increases the size of struct ib_uverbs_device to 168 bytes across 3 cachelines from 80 bytes in 2 cachelines. However, we rearrange the members so that everything fits into the first cacheline except for the struct cdev. Finally, we don't touch the cdev in any fastpaths, so this change shouldn't negatively affect performance. Signed-off-by: Alex Chiang <achiang@hp.com> Signed-off-by: Roland Dreier <rolandd@cisco.com>
2008-07-14RDMA: Remove subversion $Id tagsRoland Dreier1-2/+0
They don't get updated by git and so they're worse than useless. Signed-off-by: Roland Dreier <rolandd@cisco.com>
2008-04-19IB: convert struct class_device to struct deviceTony Jones1-2/+2
This converts the main ib_device to use struct device instead of struct class_device as class_device is going away. Signed-off-by: Tony Jones <tonyj@suse.de> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Cc: Roland Dreier <rolandd@cisco.com> Cc: Sean Hefty <sean.hefty@intel.com> Cc: Hal Rosenstock <hal.rosenstock@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-04-16IB/uverbs: Don't store struct file * for event filesRoland Dreier1-2/+2
The file member of struct ib_uverbs_event_file was only used to keep track of whether the file had been closed or not. The only thing we ever did with the value was check if it was NULL or not. Simplify the code and get rid of the need to keep track of the struct file * we allocate by replacing the file member with an is_closed member. Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-10-09IB/uverbs: Make ib_uverbs_release_event_file() staticRoland Dreier1-1/+0
ib_uverbs_release_event_file() is only used in uverbs_main.c, so make it static to that file. Also move the definition before the first use, so a forward declaration is not needed. Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-05-08IB/uverbs: Export ib_umem_get()/ib_umem_release() to modulesRoland Dreier1-5/+1
Export ib_umem_get()/ib_umem_release() and put low-level drivers in control of when to call ib_umem_get() to pin and DMA map userspace, rather than always calling it in ib_uverbs_reg_mr() before calling the low-level driver's reg_user_mr method. Also move these functions to be in the ib_core module instead of ib_uverbs, so that driver modules using them do not depend on ib_uverbs. This has a number of advantages: - It is better design from the standpoint of making generic code a library that can be used or overridden by device-specific code as the details of specific devices dictate. - Drivers that do not need to pin userspace memory regions do not need to take the performance hit of calling ib_mem_get(). For example, although I have not tried to implement it in this patch, the ipath driver should be able to avoid pinning memory and just use copy_{to,from}_user() to access userspace memory regions. - Buffers that need special mapping treatment can be identified by the low-level driver. For example, it may be possible to solve some Altix-specific memory ordering issues with mthca CQs in userspace by mapping CQ buffers with extra flags. - Drivers that need to pin and DMA map userspace memory for things other than memory regions can use ib_umem_get() directly, instead of hacks using extra parameters to their reg_phys_mr method. For example, the mlx4 driver that is pending being merged needs to pin and DMA map QP and CQ buffers, but it does not need to create a memory key for these buffers. So the cleanest solution is for mlx4 to call ib_umem_get() in the create_qp and create_cq methods. Signed-off-by: Roland Dreier <rolandd@cisco.com>
2006-08-03IB/uverbs: Avoid a crash on device hot removeJack Morgenstein1-0/+2
Wait until all users have closed their device context before allowing device unregistration to complete. This prevents a crash caused by referring to stale data structures. A better solution would be to have a way to revoke contexts rather than waiting for userspace to close the context, but that's a much bigger change that will have to wait. For now let's at least avoid the crash. Signed-off-by: Jack Morgenstein <jackm@mellanox.co.il> Signed-off-by: Michael S. Tsirkin <mst@mellanox.co.il> Signed-off-by: Roland Dreier <rolandd@cisco.com>
2006-06-17IB/uverbs: Don't serialize with ib_uverbs_idr_mutexRoland Dreier1-1/+3
Currently, all userspace verbs operations that call into the kernel are serialized by ib_uverbs_idr_mutex. This can be a scalability issue for some workloads, especially for devices driven by the ipath driver, which needs to call into the kernel even for datapath operations. Fix this by adding reference counts to the userspace objects, and then converting ib_uverbs_idr_mutex into a spinlock that only protects the idrs long enough to take a reference on the object being looked up. Because remove operations may fail, we have to do a slightly funky two-step deletion, which is described in the comments at the top of uverbs_cmd.c. This also still leaves ib_uverbs_idr_lock as a single lock that is possibly subject to contention. However, the lock hold time will only be a single idr operation, so multiple threads should still be able to make progress, even if ib_uverbs_idr_lock is being ping-ponged. Surprisingly, these changes even shrink the object code: add/remove: 23/5 grow/shrink: 4/21 up/down: 633/-693 (-60) Signed-off-by: Roland Dreier <rolandd@cisco.com>
2006-03-20IB/uverbs: Support for query SRQ from userspaceDotan Barak1-0/+1
Add support to uverbs to handle querying userspace SRQs (shared receive queues), including adding an ABI for marshalling requests and responses. The kernel midlayer already has the underlying ib_query_srq() function. Signed-off-by: Dotan Barak <dotanb@mellanox.co.il> Signed-off-by: Roland Dreier <rolandd@cisco.com>
2006-03-20IB/uverbs: Support for query QP from userspaceDotan Barak1-0/+1
Add support to uverbs to handle querying userspace QPs (queue pairs), including adding an ABI for marshalling requests and responses. The kernel midlayer already has the underlying ib_query_qp() function. Signed-off-by: Dotan Barak <dotanb@mellanox.co.il> Signed-off-by: Roland Dreier <rolandd@cisco.com>
2006-03-20IB: Add userspace support for resizing CQsRoland Dreier1-1/+2
Add support to uverbs to handle resizing userspace CQs (completion queues), including adding an ABI for marshalling requests and responses. The kernel midlayer already has ib_resize_cq(). Signed-off-by: Roland Dreier <rolandd@cisco.com>
2006-01-13IB: convert from semaphores to mutexesIngo Molnar1-2/+3
semaphore to mutex conversion by Ingo and Arjan's script. Signed-off-by: Ingo Molnar <mingo@elte.hu> [ Sanity-checked on real IB hardware ] Signed-off-by: Roland Dreier <rolandd@cisco.com>
2005-11-29IB/uverbs: track multicast group membership for userspace QPsJack Morgenstein1-0/+11
uverbs needs to track which multicast groups is each qp attached to, in order to properly detach when cleanup is performed on device file close. Signed-off-by: Jack Morgenstein <jackm@mellanox.co.il> Signed-off-by: Michael S. Tsirkin <mst@mellanox.co.il> Signed-off-by: Roland Dreier <rolandd@cisco.com>
2005-10-31[IB] uverbs: Avoid NULL pointer deref on CQ async eventRoland Dreier1-0/+1
Userspace CQs that have no completion event channel attached end up with their cq_context set to NULL. However, asynchronous events like "CQ overrun" can still occur on such CQs, so add a uverbs_file member to struct ib_ucq_object that we can follow to deliver these events. Signed-off-by: Roland Dreier <rolandd@cisco.com>
2005-10-28[IB] uverbs: Fix device lifetime problemsRoland Dreier1-6/+30
Move ib_uverbs module to using cdev_alloc() and class_device_create() so that we can handle device lifetime properly. Now we can make sure we keep all of our data structures around until the last way to reach them is gone. Signed-off-by: Roland Dreier <rolandd@cisco.com>
2005-10-17[IB] uverbs: Implement more commandsRoland Dreier1-0/+8
Add kernel support for userspace calling poll CQ, request CQ notification, post send, post receive, post SRQ receive, create AH and destroy AH commands. These commands allow us to support userspace verbs for devices that can't perform these operations directly from userspace (eg the PathScale HCA). Signed-off-by: Roland Dreier <rolandd@cisco.com>
2005-10-17[IB] uverbs: ABI-breaking fixes for userspace verbsRoland Dreier1-7/+11
Introduce new userspace verbs ABI version 3. This eliminates some unneeded commands, and adds support for user-created completion channels. This cleans up problems with file leaks on error paths, and also makes sure that file descriptors are always installed into the correct process. Signed-off-by: Roland Dreier <rolandd@cisco.com>
2005-09-26[IB] uverbs: Close some exploitable racesRoland Dreier1-0/+1
Al Viro pointed out that the current IB userspace verbs interface allows userspace to cause mischief by closing file descriptors before we're ready, or issuing the same command twice at the same time. This patch closes those races, and fixes other obvious problems such as a module reference leak. Some other interface bogosities will require an ABI change to fix properly, so I'm deferring those fixes until 2.6.15. Signed-off-by: Roland Dreier <rolandd@cisco.com>
2005-09-09Make sure that userspace does not retrieve stale asynchronous orRoland Dreier1-9/+17
completion events after destroying a CQ, QP or SRQ. We do this by sweeping the event lists before returning from a destroy calls, and then return the number of events already reported before the destroy call. This allows userspace wait until it has processed all events for an object returned from the kernel before it frees its context for the object. The ABI of the destroy CQ, destroy QP and destroy SRQ commands has to change to return the event count, so bump the ABI version from 1 to 2. The userspace libibverbs library has already been updated to handle both the old and new ABI versions. Signed-off-by: Roland Dreier <rolandd@cisco.com>
2005-08-26[PATCH] IB: move include files to include/rdmaRoland Dreier1-2/+2
Move the InfiniBand headers from drivers/infiniband/include to include/rdma. This allows InfiniBand-using code to live elsewhere, and lets us remove the ugly EXTRA_CFLAGS include path from the InfiniBand Makefiles. Signed-off-by: Roland Dreier <rolandd@cisco.com>
2005-08-26[PATCH] IB: userspace SRQ supportRoland Dreier1-0/+5
Add SRQ support to userspace verbs module. This adds several commands and associated structures, but it's OK to do this without bumping the ABI version because the commands are added at the end of the list so they don't change the existing numbering. There are two cases to worry about: 1. New kernel, old userspace. This is OK because old userspace simply won't try to use the new SRQ commands. None of the old commands are changed. 2. Old kernel, new userspace. This works perfectly as long as userspace doesn't try to use SRQ commands. If userspace tries to use SRQ commands, it will get EINVAL, which is perfectly reasonable: the kernel doesn't support SRQs, so we couldn't do any better. Signed-off-by: Roland Dreier <rolandd@cisco.com>
2005-08-26[PATCH] IB: Add copyright noticesRoland Dreier1-0/+2
Make some lawyers happy and add copyright notices for people who forgot to include them when they actually touched the code. Signed-off-by: Roland Dreier <rolandd@cisco.com>
2005-07-27[IB/uverbs]: Add O_ASYNC supportGleb Natapov1-0/+1
Add support for O_ASYNC notifications on userspace verbs completion and asynchronous event file descriptors. Signed-off-by: Gleb Natapov <glebn@voltaire.com> Signed-off-by: Roland Dreier <rolandd@cisco.com>
2005-07-07[PATCH] IB uverbs: core implementationRoland Dreier1-0/+132
Add the core of the InfiniBand userspace verbs implementation, including creating character device nodes, dispatching requests from userspace, and passing event notifications back up to userspace. Signed-off-by: Roland Dreier <rolandd@cisco.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>