kernel.git/fs/nfs/inode.c, branch linux-3.17.y

nfs: Fix use of uninitialized variable in nfs_getattr()

2014-11-21T17:23:14Z

commit 16caf5b6101d03335b386e77e9e14136f989be87 upstream. Variable 'err' needn't be initialized when nfs_getattr() uses it to check whether it should call generic_fillattr() or not. That can result in spurious error returns. Initialize 'err' properly. Signed-off-by: Jan Kara Signed-off-by: Trond Myklebust Signed-off-by: Greg Kroah-Hartman

Merge tag 'nfs-for-3.17-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs

2014-08-14T00:13:19Z

Pull NFS client updates from Trond Myklebust: "Highlights include: - stable fix for a bug in nfs3_list_one_acl() - speed up NFS path walks by supporting LOOKUP_RCU - more read/write code cleanups - pNFS fixes for layout return on close - fixes for the RCU handling in the rpcsec_gss code - more NFS/RDMA fixes" * tag 'nfs-for-3.17-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (79 commits) nfs: reject changes to resvport and sharecache during remount NFS: Avoid infinite loop when RELEASE_LOCKOWNER getting expired error SUNRPC: remove all refcounting of groupinfo from rpcauth_lookupcred NFS: fix two problems in lookup_revalidate in RCU-walk NFS: allow lockless access to access_cache NFS: teach nfs_lookup_verify_inode to handle LOOKUP_RCU NFS: teach nfs_neg_need_reval to understand LOOKUP_RCU NFS: support RCU_WALK in nfs_permission() sunrpc/auth: allow lockless (rcu) lookup of credential cache. NFS: prepare for RCU-walk support but pushing tests later in code. NFS: nfs4_lookup_revalidate: only evaluate parent if it will be used. NFS: add checks for returned value of try_module_get() nfs: clear_request_commit while holding i_lock pnfs: add pnfs_put_lseg_async pnfs: find swapped pages on pnfs commit lists too nfs: fix comment and add warn_on for PG_INODE_REF nfs: check wait_on_bit_lock err in page_group_lock sunrpc: remove "ec" argument from encrypt_v2 operation sunrpc: clean up sparse endianness warnings in gss_krb5_wrap.c sunrpc: clean up sparse endianness warnings in gss_krb5_seal.c ...

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace

2014-08-10T00:10:41Z

Pull namespace updates from Eric Biederman: "This is a bunch of small changes built against 3.16-rc6. The most significant change for users is the first patch which makes setns drmatically faster by removing unneded rcu handling. The next chunk of changes are so that "mount -o remount,.." will not allow the user namespace root to drop flags on a mount set by the system wide root. Aks this forces read-only mounts to stay read-only, no-dev mounts to stay no-dev, no-suid mounts to stay no-suid, no-exec mounts to stay no exec and it prevents unprivileged users from messing with a mounts atime settings. I have included my test case as the last patch in this series so people performing backports can verify this change works correctly. The next change fixes a bug in NFS that was discovered while auditing nsproxy users for the first optimization. Today you can oops the kernel by reading /proc/fs/nfsfs/{servers,volumes} if you are clever with pid namespaces. I rebased and fixed the build of the !CONFIG_NFS_FS case yesterday when a build bot caught my typo. Given that no one to my knowledge bases anything on my tree fixing the typo in place seems more responsible that requiring a typo-fix to be backported as well. The last change is a small semantic cleanup introducing /proc/thread-self and pointing /proc/mounts and /proc/net at it. This prevents several kinds of problemantic corner cases. It is a user-visible change so it has a minute chance of causing regressions so the change to /proc/mounts and /proc/net are individual one line commits that can be trivially reverted. Unfortunately I lost and could not find the email of the original reporter so he is not credited. From at least one perspective this change to /proc/net is a refgression fix to allow pthread /proc/net uses that were broken by the introduction of the network namespace" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: proc: Point /proc/mounts at /proc/thread-self/mounts instead of /proc/self/mounts proc: Point /proc/net at /proc/thread-self/net instead of /proc/self/net proc: Implement /proc/thread-self to point at the directory of the current thread proc: Have net show up under /proc//task/ NFS: Fix /proc/fs/nfsfs/servers and /proc/fs/nfsfs/volumes mnt: Add tests for unprivileged remount cases that have found to be faulty mnt: Change the default remount atime from relatime to the existing value mnt: Correct permission checks in do_remount mnt: Move the test for MNT_LOCK_READONLY from change_mount_flags into do_remount mnt: Only change user settable mount flags in remount namespaces: Use task_lock and not rcu to protect nsproxy

NFS: Fix /proc/fs/nfsfs/servers and /proc/fs/nfsfs/volumes

2014-08-04T16:28:32Z

The usage of pid_ns->child_reaper->nsproxy->net_ns in nfs_server_list_open and nfs_client_list_open is not safe. /proc for a pid namespace can remain mounted after the all of the process in that pid namespace have exited. There are also times before the initial process in a pid namespace has started or after the initial process in a pid namespace has exited where pid_ns->child_reaper can be NULL or stale. Making the idiom pid_ns->child_reaper->nsproxy a double whammy of problems. Luckily all that needs to happen is to move /proc/fs/nfsfs/servers and /proc/fs/nfsfs/volumes under /proc/net to /proc/net/nfsfs/servers and /proc/net/nfsfs/volumes and add a symlink from the original location, and to use seq_open_net as it has been designed. Cc: stable@vger.kernel.org Cc: Trond Myklebust Cc: Stanislav Kinsbursky Signed-off-by: "Eric W. Biederman"

NFS: teach nfs_neg_need_reval to understand LOOKUP_RCU

2014-08-03T21:14:12Z

This requires nfs_check_verifier to take an rcu_walk flag, and requires an rcu version of nfs_revalidate_inode which returns -ECHILD rather than making an RPC call. With this, nfs_lookup_revalidate can call nfs_neg_need_reval in RCU-walk mode. We can also move the LOOKUP_RCU check past the nfs_check_verifier() call in nfs_lookup_revalidate. If RCU_WALK prevents nfs_check_verifier or nfs_neg_need_reval from doing a full check, they return a status indicating that a revalidation is required. As this revalidation will not be possible in RCU_WALK mode, -ECHILD will ultimately be returned, which is the desired result. Signed-off-by: NeilBrown Signed-off-by: Trond Myklebust

sched: Allow wait_on_bit_action() functions to support a timeout

2014-07-16T13:10:41Z

It is currently not possible for various wait_on_bit functions to implement a timeout. While the "action" function that is called to do the waiting could certainly use schedule_timeout(), there is no way to carry forward the remaining timeout after a false wake-up. As false-wakeups a clearly possible at least due to possible hash collisions in bit_waitqueue(), this is a real problem. The 'action' function is currently passed a pointer to the word containing the bit being waited on. No current action functions use this pointer. So changing it to something else will be a little noisy but will have no immediate effect. This patch changes the 'action' function to take a pointer to the "struct wait_bit_key", which contains a pointer to the word containing the bit so nothing is really lost. It also adds a 'private' field to "struct wait_bit_key", which is initialized to zero. An action function can now implement a timeout with something like static int timed_out_waiter(struct wait_bit_key *key) { unsigned long waited; if (key->private == 0) { key->private = jiffies; if (key->private == 0) key->private -= 1; } waited = jiffies - key->private; if (waited > 10 * HZ) return -EAGAIN; schedule_timeout(waited - 10 * HZ); return 0; } If any other need for context in a waiter were found it would be easy to use ->private for some other purpose, or even extend "struct wait_bit_key". My particular need is to support timeouts in nfs_release_page() to avoid deadlocks with loopback mounted NFS. While wait_on_bit_timeout() would be a cleaner interface, it will not meet my need. I need the timeout to be sensitive to the state of the connection with the server, which could change. So I need to use an 'action' interface. Signed-off-by: NeilBrown Acked-by: Peter Zijlstra Cc: Oleg Nesterov Cc: Steve French Cc: David Howells Cc: Steven Whitehouse Cc: Linus Torvalds Link: http://lkml.kernel.org/r/20140707051604.28027.41257.stgit@notabene.brown Signed-off-by: Ingo Molnar

sched: Remove proliferation of wait_on_bit() action functions

2014-07-16T13:10:39Z

The current "wait_on_bit" interface requires an 'action' function to be provided which does the actual waiting. There are over 20 such functions, many of them identical. Most cases can be satisfied by one of just two functions, one which uses io_schedule() and one which just uses schedule(). So: Rename wait_on_bit and wait_on_bit_lock to wait_on_bit_action and wait_on_bit_lock_action to make it explicit that they need an action function. Introduce new wait_on_bit{,_lock} and wait_on_bit{,_lock}_io which are *not* given an action function but implicitly use a standard one. The decision to error-out if a signal is pending is now made based on the 'mode' argument rather than being encoded in the action function. All instances of the old wait_on_bit and wait_on_bit_lock which can use the new version have been changed accordingly and their action functions have been discarded. wait_on_bit{_lock} does not return any specific error code in the event of a signal so the caller must check for non-zero and interpolate their own error code as appropriate. The wait_on_bit() call in __fscache_wait_on_invalidate() was ambiguous as it specified TASK_UNINTERRUPTIBLE but used fscache_wait_bit_interruptible as an action function. David Howells confirms this should be uniformly "uninterruptible" The main remaining user of wait_on_bit{,_lock}_action is NFS which needs to use a freezer-aware schedule() call. A comment in fs/gfs2/glock.c notes that having multiple 'action' functions is useful as they display differently in the 'wchan' field of 'ps'. (and /proc/$PID/wchan). As the new bit_wait{,_io} functions are tagged "__sched", they will not show up at all, but something higher in the stack. So the distinction will still be visible, only with different function names (gds2_glock_wait versus gfs2_glock_dq_wait in the gfs2/glock.c case). Since first version of this patch (against 3.15) two new action functions appeared, on in NFS and one in CIFS. CIFS also now uses an action function that makes the same freezer aware schedule call as NFS. Signed-off-by: NeilBrown Acked-by: David Howells (fscache, keys) Acked-by: Steven Whitehouse (gfs2) Acked-by: Peter Zijlstra Cc: Oleg Nesterov Cc: Steve French Cc: Linus Torvalds Link: http://lkml.kernel.org/r/20140707051603.28027.72349.stgit@notabene.brown Signed-off-by: Ingo Molnar

NFS: Don't mark the data cache as invalid if it has been flushed

2014-06-24T22:46:57Z

Now that we have functions such as nfs_write_pageuptodate() that use the cache_validity flags to check if the data cache is valid or not, it is a little more important to keep the flags in sync with the state of the data cache. In particular, we'd like to ensure that if the data cache is empty, we don't start marking it as needing revalidation. Reported-by: Scott Mayhew Signed-off-by: Trond Myklebust

NFS: Clear NFS_INO_REVAL_PAGECACHE when we update the file size

2014-06-24T22:46:57Z

In nfs_update_inode(), if the change attribute is seen to change on the server, then we set NFS_INO_REVAL_PAGECACHE in order to make sure that we check the file size. However, if we also update the file size in the same function, we don't need to check it again. So make sure that we clear the NFS_INO_REVAL_PAGECACHE that was set earlier. Signed-off-by: Trond Myklebust

Merge tag 'nfs-for-3.16-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs

2014-06-10T22:02:42Z

Pull NFS client updates from Trond Myklebust: "Highlights include: - massive cleanup of the NFS read/write code by Anna and Dros - support multiple NFS read/write requests per page in order to deal with non-page aligned pNFS striping. Also cleans up the r/wsize < page size code nicely. - stable fix for ensuring inode is declared uptodate only after all the attributes have been checked. - stable fix for a kernel Oops when remounting - NFS over RDMA client fixes - move the pNFS files layout driver into its own subdirectory" * tag 'nfs-for-3.16-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (79 commits) NFS: populate ->net in mount data when remounting pnfs: fix lockup caused by pnfs_generic_pg_test NFSv4.1: Fix typo in dprintk NFSv4.1: Comment is now wrong and redundant to code NFS: Use raw_write_seqcount_begin/end int nfs4_reclaim_open_state xprtrdma: Disconnect on registration failure xprtrdma: Remove BUG_ON() call sites xprtrdma: Avoid deadlock when credit window is reset SUNRPC: Move congestion window constants to header file xprtrdma: Reset connection timeout after successful reconnect xprtrdma: Use macros for reconnection timeout constants xprtrdma: Allocate missing pagelist xprtrdma: Remove Tavor MTU setting xprtrdma: Ensure ia->ri_id->qp is not NULL when reconnecting xprtrdma: Reduce the number of hardway buffer allocations xprtrdma: Limit work done by completion handler xprtrmda: Reduce calls to ib_poll_cq() in completion handlers xprtrmda: Reduce lock contention in completion handlers xprtrdma: Split the completion queue xprtrdma: Make rpcrdma_ep_destroy() return void ...