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* MFC: r291638rmacklem2015-12-161-0/+1
| | | | | | | Fix the memory leak that occurs when the nfscommon.ko module is unloaded. This leak was introduced by r291527 (r292223 in stable/10). Since the nfscommon.ko module is rarely unloaded, this leak would not have been much of an issue.
* MFC: r291527rmacklem2015-12-141-0/+1
| | | | | | | | | | | | | | | | Add kernel support to the NFS server for the "-manage-gids" option that will be added to the nfsuserd daemon in a future commit. It modifies the cache used by NFSv4 for name<-->id translation (both username/uid and group/gid) to support this. When "-manage-gids" is set, the server looks up each uid for the RPC and uses the list of groups cached in the server instead of the list of groups provided in the RPC request. The cached group list is acquired for the cache by the nfsuserd daemon via getgrouplist(3). This avoids the 16 groups limit for the list in the RPC request. Since the cache is now used for every RPC when "-manage-gids" is enabled, the code also modifies the cache to use a separate mutex for each hash list instead of a single global mutex.
* MFC: r291150rmacklem2015-12-051-0/+1
| | | | | | | | | | | | | When the nfsd threads are terminated, the NFSv4 server state (opens, locks, etc) is retained, which I believe is correct behaviour. However, for NFSv4.1, the server also retained a reference to the xprt (RPC transport socket structure) for the backchannel. This caused svcpool_destroy() to not call SVC_DESTROY() for the xprt and allowed a socket upcall to occur after the mutexes in the svcpool were destroyed, causing a crash. This patch fixes the code so that the backchannel xprt structure is dereferenced just before svcpool_destroy() is called, so the code does do an SVC_DESTROY() on the xprt, which shuts down the socket upcall.
* MFC: r268115rmacklem2014-08-011-6/+36
| | | | | | | | Merge the NFSv4.1 server code in projects/nfsv4.1-server over into head. The code is not believed to have any effect on the semantics of non-NFSv4.1 server behaviour. It is a rather large merge, but I am hoping that there will not be any regressions for the NFS server.
* MFC r260229, r260258, r260367, r260390, r260459, r260648:mav2014-01-221-7/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Rework NFS Duplicate Request Cache cleanup logic. - Introduce additional hash to group requests by hash of sockref. This allows to process TCP acknowledgements without looping though all the cache, and as result allows to do it every time. - Indroduce additional callbacks to notify application layer about sockets disconnection. Without this last few requests processed just before socket disconnection never processed their ACKs and stuck in cache for many hours. - Implement transport-specific method for tracking reply acknowledgements. New implementation does not cross multiple stack layers to get the data and does not have race conditions that previously made some requests stuck in cache. This could be done more efficiently at sockbuf layer, but that would broke some KBIs, while I don't know other consumers for it aside NFS. - Instead of traversing all DRC twice per request, run cleaning only once per request, and except in some conditions traverse only single hash slot at a time. Together this limits NFS DRC growth only to situations of real connectivity problems. If network is working well, and so all replies are acknowledged, cache remains almost empty even after hours of heavy load. Without this change on the same test cache was growing to many thousand requests even with perfectly working local network. As another result this reduces CPU time spent on the DRC handling during SPEC NFS benchmark from about 10% to 0.5%. Sponsored by: iXsystems, Inc.
* MFC: r259854rmacklem2014-01-011-1/+1
| | | | | | | The NFSv4 server would call VOP_SETATTR() with a shared locked vnode when a Getattr for a file is done by a client other than the one that holds the file's delegation. This would only happen when delegations are enabled and the problem is fixed by this patch.
* MFC: r257901rmacklem2013-12-111-1/+2
| | | | | | | Fix an NFSv4.1 client specific case where a forced dismount would hang. The hang occurred in nfsv4_setsequence() when it couldn't find an available session slot and is fixed by checking for a forced dismount in progress and just returning for this case.
* Revamp the old NFS server's File Handle Affinity (FHA) code so thatken2013-04-171-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | it will work with either the old or new server. The FHA code keeps a cache of currently active file handles for NFSv2 and v3 requests, so that read and write requests for the same file are directed to the same group of threads (reads) or thread (writes). It does not currently work for NFSv4 requests. They are more complex, and will take more work to support. This improves read-ahead performance, especially with ZFS, if the FHA tuning parameters are configured appropriately. Without the FHA code, concurrent reads that are part of a sequential read from a file will be directed to separate NFS threads. This has the effect of confusing the ZFS zfetch (prefetch) code and makes sequential reads significantly slower with clients like Linux that do a lot of prefetching. The FHA code has also been updated to direct write requests to nearby file offsets to the same thread in the same way it batches reads, and the FHA code will now also send writes to multiple threads when needed. This improves sequential write performance in ZFS, because writes to a file are now more ordered. Since NFS writes (generally less than 64K) are smaller than the typical ZFS record size (usually 128K), out of order NFS writes to the same block can trigger a read in ZFS. Sending them down the same thread increases the odds of their being in order. In order for multiple write threads per file in the FHA code to be useful, writes in the NFS server have been changed to use a LK_SHARED vnode lock, and upgrade that to LK_EXCLUSIVE if the filesystem doesn't allow multiple writers to a file at once. ZFS is currently the only filesystem that allows multiple writers to a file, because it has internal file range locking. This change does not affect the NFSv4 code. This improves random write performance to a single file in ZFS, since we can now have multiple writers inside ZFS at one time. I have changed the default tuning parameters to a 22 bit (4MB) window size (from 256K) and unlimited commands per thread as a result of my benchmarking with ZFS. The FHA code has been updated to allow configuring the tuning parameters from loader tunable variables in addition to sysctl variables. The read offset window calculation has been slightly modified as well. Instead of having separate bins, each file handle has a rolling window of bin_shift size. This minimizes glitches in throughput when shifting from one bin to another. sys/conf/files: Add nfs_fha_new.c and nfs_fha_old.c. Compile nfs_fha.c when either the old or the new NFS server is built. sys/fs/nfs/nfsport.h, sys/fs/nfs/nfs_commonport.c: Bring in changes from Rick Macklem to newnfs_realign that allow it to operate in blocking (M_WAITOK) or non-blocking (M_NOWAIT) mode. sys/fs/nfs/nfs_commonsubs.c, sys/fs/nfs/nfs_var.h: Bring in a change from Rick Macklem to allow telling nfsm_dissect() whether or not to wait for mallocs. sys/fs/nfs/nfsm_subs.h: Bring in changes from Rick Macklem to create a new nfsm_dissect_nonblock() inline function and NFSM_DISSECT_NONBLOCK() macro. sys/fs/nfs/nfs_commonkrpc.c, sys/fs/nfsclient/nfs_clkrpc.c: Add the malloc wait flag to a newnfs_realign() call. sys/fs/nfsserver/nfs_nfsdkrpc.c: Setup the new NFS server's RPC thread pool so that it will call the FHA code. Add the malloc flag argument to newnfs_realign(). Unstaticize newnfs_nfsv3_procid[] so that we can use it in the FHA code. sys/fs/nfsserver/nfs_nfsdsocket.c: In nfsrvd_dorpc(), add NFSPROC_WRITE to the list of RPC types that use the LK_SHARED lock type. sys/fs/nfsserver/nfs_nfsdport.c: In nfsd_fhtovp(), if we're starting a write, check to see whether the underlying filesystem supports shared writes. If not, upgrade the lock type from LK_SHARED to LK_EXCLUSIVE. sys/nfsserver/nfs_fha.c: Remove all code that is specific to the NFS server implementation. Anything that is server-specific is now accessed through a callback supplied by that server's FHA shim in the new softc. There are now separate sysctls and tunables for the FHA implementations for the old and new NFS servers. The new NFS server has its tunables under vfs.nfsd.fha, the old NFS server's tunables are under vfs.nfsrv.fha as before. In fha_extract_info(), use callouts for all server-specific code. Getting file handles and offsets is now done in the individual server's shim module. In fha_hash_entry_choose_thread(), change the way we decide whether two reads are in proximity to each other. Previously, the calculation was a simple shift operation to see whether the offsets were in the same power of 2 bucket. The issue was that there would be a bucket (and therefore thread) transition, even if the reads were in close proximity. When there is a thread transition, reads wind up going somewhat out of order, and ZFS gets confused. The new calculation simply tries to see whether the offsets are within 1 << bin_shift of each other. If they are, the reads will be sent to the same thread. The effect of this change is that for sequential reads, if the client doesn't exceed the max_reqs_per_nfsd parameter and the bin_shift is set to a reasonable value (22, or 4MB works well in my tests), the reads in any sequential stream will largely be confined to a single thread. Change fha_assign() so that it takes a softc argument. It is now called from the individual server's shim code, which will pass in the softc. Change fhe_stats_sysctl() so that it takes a softc parameter. It is now called from the individual server's shim code. Add the current offset to the list of things printed out about each active thread. Change the num_reads and num_writes counters in the fha_hash_entry structure to 32-bit values, and rename them num_rw and num_exclusive, respectively, to reflect their changed usage. Add an enable sysctl and tunable that allows the user to disable the FHA code (when vfs.XXX.fha.enable = 0). This is useful for before/after performance comparisons. nfs_fha.h: Move most structure definitions out of nfs_fha.c and into the header file, so that the individual server shims can see them. Change the default bin_shift to 22 (4MB) instead of 18 (256K). Allow unlimited commands per thread. sys/nfsserver/nfs_fha_old.c, sys/nfsserver/nfs_fha_old.h, sys/fs/nfsserver/nfs_fha_new.c, sys/fs/nfsserver/nfs_fha_new.h: Add shims for the old and new NFS servers to interface with the FHA code, and callbacks for the The shims contain all of the code and definitions that are specific to the NFS servers. They setup the server-specific callbacks and set the server name for the sysctl and loader tunable variables. sys/nfsserver/nfs_srvkrpc.c: Configure the RPC code to call fhaold_assign() instead of fha_assign(). sys/modules/nfsd/Makefile: Add nfs_fha.c and nfs_fha_new.c. sys/modules/nfsserver/Makefile: Add nfs_fha_old.c. Reviewed by: rmacklem Sponsored by: Spectra Logic MFC after: 2 weeks
* Move the NFSv4.1 client patches over from projects/nfsv4.1-clientrmacklem2012-12-081-8/+60
| | | | | | | | | | to head. I don't think the NFS client behaviour will change unless the new "minorversion=1" mount option is used. It includes basic NFSv4.1 support plus support for pNFS using the Files Layout only. All problems detecting during an NFSv4.1 Bakeathon testing event in June 2012 have been resolved in this code and it has been tested against the NFSv4.1 server available to me. Although not reviewed, I believe that kib@ has looked at it.
* Add an nfssvc() option to the kernel for the new NFS clientrmacklem2012-12-021-0/+1
| | | | | | | | which dumps out the actual options being used by an NFS mount. This will be used to implement a "-m" option for nfsstat(1). Reviewed by: alfred MFC after: 2 weeks
* Modify the NFSv4 client so that it can handle ownerrmacklem2012-09-201-2/+4
| | | | | | | | | | | | | | | and owner_group strings that consist entirely of digits, interpreting them as the uid/gid number. This change was needed since new (>= 3.3) Linux servers reply with these strings by default. This change is mandated by the rfc3530bis draft. Reported on freebsd-stable@ under the Subject heading "Problem with Linux >= 3.3 as NFSv4 server" by Norbert Aschendorff on Aug. 20, 2012. Tested by: norbert.aschendorff at yahoo.de Reviewed by: jhb MFC after: 2 weeks
* Add two arguments to the nfsrpc_rellockown() function in the NFSv4rmacklem2011-11-201-2/+2
| | | | | | | | client. This does not change the client's behaviour, but prepares the code so that nfsrpc_rellockown() can be called elsewhere in a future commit. MFC after: 2 weeks
* Move nfsvno_pathconf to be accessible to sys/fs/nfs; no functionality change.zack2011-07-161-2/+2
| | | | | | Reviewed by: rmacklem Approved by: zml (mentor) MFC after: 2 weeks
* Modify the new NFSv4 client so that it appends a file handlermacklem2011-07-031-0/+1
| | | | | | | | | | | | | to the lock_owner4 string that goes on the wire. Also, add code to do a ReleaseLockOwner Op on the lock_owner4 string before a Close. Apparently not all NFSv4 servers handle multiple instances of the same lock_owner4 string, at least not in a compatible way. This patch avoids having multiple instances, except for one unusual case, which will be fixed by a future commit. Found at the recent NFSv4 interoperability Bakeathon. Tested by: tdh at excfb.com MFC after: 2 weeks
* The new NFSv4 client was erroneously using "p" instead ofrmacklem2011-06-051-9/+10
| | | | | | | | | | "p_leader" for the "id" for POSIX byte range locking. I think this would only have affected processes created by rfork(2) with the RFTHREAD flag specified. This patch fixes that by passing the "id" down through the various functions from nfs_advlock(). MFC after: 2 weeks
* Fix the new NFS client so that it handles NFSv4 statermacklem2011-05-271-2/+2
| | | | | | | | | | | | | | | | | correctly during a forced dismount. This required that the exclusive and shared (refcnt) sleep lock functions check for MNTK_UMOUNTF before sleeping, so that they won't block while nfscl_umount() is getting rid of the state. As such, a "struct mount *" argument was added to the locking functions. I believe the only remaining case where a forced dismount can get hung in the kernel is when a thread is already attempting to do a TCP connect to a dead server when the krpc client structure called nr_client is NULL. This will only happen just after a "mount -u" with options that force a new TCP connection is done, so it shouldn't be a problem in practice. MFC after: 2 weeks
* Fix the new NFS client so that it correctly sets the "must_commit"rmacklem2011-05-251-1/+1
| | | | | | | | argument for a write RPC when it succeeds for the first one and fails for a subsequent RPC within the same call to the function. This makes it compatible with the old NFS client for this case. MFC after: 2 weeks
* Modify the experimental (newnfs) NFS client so that it uses thermacklem2011-04-251-1/+0
| | | | | | | | same diskless NFS root code as the regular client, which was moved to sys/nfs by r221032. This fixes the newnfs client so that it can do an NFSv3 diskless root file system. MFC after: 2 weeks
* Add a lktype flags argument to nfscl_nget() and ncl_nget() in thermacklem2011-04-161-1/+1
| | | | | | | experimental NFS client so that its nfs_lookup() function can use cn_lkflags in a manner analagous to the regular NFS client. MFC after: 2 weeks
* Fix the experimental NFSv4 server so that it uses VOP_PATHCONF()rmacklem2011-04-141-2/+3
| | | | | | | | | to determine if a file system supports NFSv4 ACLs. Since VOP_PATHCONF() must be called with a locked vnode, the function is called before nfsvno_fillattr() and the result is passed in as an extra argument. MFC after: 2 weeks
* Modify the experimental NFSv4 server so that it handlesrmacklem2011-04-141-4/+4
| | | | | | | | | | | | | crossing of server mount points properly. The functions nfsvno_fillattr() and nfsv4_fillattr() were modified to take the extra arguments that are the mount point, a flag to indicate that it is a file system root and the mounted on fileno. The mount point argument needs to be busy when nfsvno_fillattr() is called, since the vp argument is not locked. Reviewed by: kib MFC after: 2 weeks
* Add some cleanup code to the module unload operation forrmacklem2011-04-101-0/+1
| | | | | | | | | | the experimental NFS server, so that it doesn't leak memory when unloaded. However, unloading the NFSv4 server is not recommended, since all NFSv4 state will be lost by the unload and clients will have to recover the state after a server reload/restart as if the server crashed/rebooted. MFC after: 2 weeks
* Modify the experimental NFSv4 server so that it posts a SIGUSR2rmacklem2011-01-141-0/+1
| | | | | | | | | | | signal to the master nfsd daemon whenever the stable restart file has been modified. This will allow the master nfsd daemon to maintain an up to date backup copy of the file. This is enabled via the nfssvc() syscall, so that older nfsd daemons will not be signaled. Reviewed by: jhb MFC after: 1 week
* Since the VFS_LOCK_GIANT() code in the experimental NFSrmacklem2011-01-061-2/+0
| | | | | | | | | server is broken and the major file systems are now all mpsafe, modify the server so that it will only export mpsafe file systems. This was discussed on freebsd-fs@ and removes a fair bit of crufty code. MFC after: 12 days
* Delete the nfsvno_localconflict() function in the experimentalrmacklem2010-12-281-2/+0
| | | | | | NFS server since it is no longer used and is broken. MFC after: 2 weeks
* Modify the experimental NFS server so that it uses LK_SHAREDrmacklem2010-12-251-2/+2
| | | | | | | | | | | | for RPC operations when it can. Since VFS_FHTOVP() currently always gets an exclusively locked vnode and is usually called at the beginning of each RPC, the RPCs for a given vnode will still be serialized. As such, passing a lock type argument to VFS_FHTOVP() would be preferable to doing the vn_lock() with LK_DOWNGRADE after the VFS_FHTOVP() call. Reviewed by: kib MFC after: 2 weeks
* Add an argument to nfsvno_getattr() in the experimentalrmacklem2010-12-241-1/+1
| | | | | | | | | | | | | NFS server, so that it can avoid calling VOP_ISLOCKED() when the vnode is known to be locked. This will allow LK_SHARED to be used for these cases, which happen to be all the cases that can use LK_SHARED. This does not fix any bug, but it reduces the number of calls to VOP_ISLOCKED() and prepares the code so that it can be switched to using LK_SHARED in a future patch. Reviewed by: kib MFC after: 2 weeks
* Modify the experimental NFSv4 server's file handle hash functionrmacklem2010-10-231-1/+1
| | | | | | | | | | | to use the generic hash32_buf() function. Although adding the bytes seemed sufficient for UFS and ZFS, since most of the bytes are the same for file handles on the same volume, this might not be sufficient for other file systems. Use of a generic function also seems preferable to one specific to NFSv4. Suggested by: gleb.kurtsou at gmail.com MFC after: 10 days
* Modify the file handle hash function in the experimental NFSrmacklem2010-10-221-0/+1
| | | | | | | | server so that it will work better for non-UFS file systems. The new function simply sums the bytes of the fh_fid field of fhandle_t. MFC after: 10 days
* The timer routine in the experimental NFS server did not acquirermacklem2010-08-281-0/+1
| | | | | | | | | | | | the correct mutex when checking nfsv4root_lock. Although this could be fixed by adding mutex lock/unlock calls, zack.kirsch at isilon.com suggested a better fix that uses a non-blocking acquisition of a reference count on nfsv4root_lock. This fix allows the weird NFSLOCKSTATE(); NFSUNLOCKSTATE(); synchronization to be deleted. This patch applies this fix. Tested by: zack.kirsch at isilon.com MFC after: 2 weeks
* Modify the return value for nfscl_mustflush() from boolean_t,rmacklem2010-08-031-1/+1
| | | | | | | | which I mistakenly thought was correct w.r.t. style(9), back to int and add the checks for != 0. This is just a stylistic modification. MFC after: 1 week
* Change the nfscl_mustflush() function in the experimental NFSv4rmacklem2010-07-181-1/+1
| | | | | | | client to return a boolean_t in order to make it more compatible with style(9). MFC after: 2 weeks
* An NFSv4 server will reply NFSERR_GRACE for non-recovery RPCsrmacklem2010-04-241-1/+1
| | | | | | | | | | | | during the grace period after startup. This grace period must be at least the lease duration, which is typically 1-2 minutes. It seems prudent for the experimental NFS client to wait a few seconds before retrying such an RPC, so that the server isn't flooded with non-recovery RPCs during recovery. This patch adds an argument to nfs_catnap() to implement a 5 second delay for this case. MFC after: 1 week
* When the experimental NFS client is handling an NFSv4 server rebootrmacklem2010-04-221-2/+2
| | | | | | | | | | | | with delegations enabled, the recovery could fail if the renew thread is trying to return a delegation, since it will not do the recovery. This patch fixes the above by having nfscl_recalldeleg() fail with the I/O operations returning EIO, so that they will be attempted later. Most of the patch consists of adding an argument to various functions to indicate the delegation recall case where this needs to be done. MFC after: 1 week
* This patch should fix handling of byte range locks locallyrmacklem2010-03-301-0/+1
| | | | | | | | | | | on the server for the experimental nfs server. When enabled by setting vfs.newnfs.locallocks_enable to non-zero, the experimental nfs server will now acquire byte range locks on the file on behalf of NFSv4 clients, such that lock conflicts between the NFSv4 clients and processes running locally on the server, will be recognized and handled correctly. MFC after: 2 weeks
* Modify the experimental server so that it uses VOP_ACCESSX().rmacklem2009-12-251-4/+2
| | | | | | | | | | This is necessary in order to enable NFSv4 ACL support. The argument to nfsvno_accchk() was changed to an accmode_t and the function nfsrv_aclaccess() was no longer needed and, therefore, deleted. Reviewed by: trasz MFC after: 2 weeks
* Remove unneeded ifdefs.trasz2009-12-031-2/+0
| | | | Reviewed by: rmacklem
* Patch the experimental NFS server is a manner analagous tormacklem2009-11-201-2/+2
| | | | | | | | | | | | | r197525, so that the creation verifier is handled correctly in va_atime for 64bit architectures. There were two problems. One was that the code incorrectly assumed that sizeof (struct timespec) == 8 and the other was that the tv_sec field needs to be assigned from a signed 32bit integer, so that sign extension occurs on 64bit architectures. This is required for correct operation when exporting ZFS volumes. Reviewed by: pjd MFC after: 2 weeks
* Since the nfscl_getclose() function both decremented open counts and,rmacklem2009-07-091-1/+3
| | | | | | | | | | | | | optionally, created a separate list of NFSv4 opens to be closed, it was possible for the associated OpenOwner to be free'd before the Open was closed. The problem was that the Open was taken off the OpenOwner list before the Close RPC was done and OpenOwners can be free'd once the list is empty. This patch separates out the case of doing the Close RPC into a separate function called nfscl_doclose() and simplifies nfsrpc_doclose() so that it closes a single open instead of a list of them. This avoids removing the Open from the OpenOwner list before doing the Close RPC. Approved by: re (kensmith), kib (mentor)
* Change the experimental NFSv4 client so that it does not dormacklem2009-05-181-3/+2
| | | | | | | | | the NFSv4 Close operations until ncl_inactive(). This is necessary so that the Open StateIDs are available for doing I/O on mmap'd files after VOP_CLOSE(). I also changed some indentation for the nfscl_getclose() function. Approved by: kib (mentor)
* Apply changes to the experimental nfs server so that it uses the securityrmacklem2009-05-141-0/+2
| | | | | | | flavors as exported in FreeBSD-CURRENT. This allows it to use a slightly modified mountd.c instead of a different utility. Approved by: kib (mentor)
* Change the file names in the comments in sys/fs/nfs/nfs_var.h sormacklem2009-05-141-34/+30
| | | | | | | that they are the names used in FreeBSD-CURRENT. Also shuffled a few entries around, so that they under the correct comment. Approved by: kib (mentor)
* Remove the thread argument from the FSD (File-System Dependent) parts ofattilio2009-05-111-1/+1
| | | | | | | | | | | | | | | | | the VFS. Now all the VFS_* functions and relating parts don't want the context as long as it always refers to curthread. In some points, in particular when dealing with VOPs and functions living in the same namespace (eg. vflush) which still need to be converted, pass curthread explicitly in order to retain the old behaviour. Such loose ends will be fixed ASAP. While here fix a bug: now, UFS_EXTATTR can be compiled alone without the UFS_EXTATTR_AUTOSTART option. VFS KPI is heavilly changed by this commit so thirdy parts modules needs to be recompiled. Bump __FreeBSD_version in order to signal such situation.
* Add the experimental nfs subtree to the kernel, that includesrmacklem2009-05-041-0/+604
support for NFSv4 as well as NFSv2 and 3. It lives in 3 subdirs under sys/fs: nfs - functions that are common to the client and server nfsclient - a mutation of sys/nfsclient that call generic functions to do RPCs and handle state. As such, it retains the buffer cache handling characteristics and vnode semantics that are found in sys/nfsclient, for the most part. nfsserver - the server. It includes a DRC designed specifically for NFSv4, that is used instead of the generic DRC in sys/rpc. The build glue will be checked in later, so at this point, it consists of 3 new subdirs that should not affect kernel building. Approved by: kib (mentor)
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