kernel.git/fs/nfs/file.c, branch linux-3.5.y

nfs: skip commit in releasepage if we're freeing memory for fs-related reasons

2012-08-09T15:23:12Z

commit 5cf02d09b50b1ee1c2d536c9cf64af5a7d433f56 upstream. We've had some reports of a deadlock where rpciod ends up with a stack trace like this: PID: 2507 TASK: ffff88103691ab40 CPU: 14 COMMAND: "rpciod/14" #0 [ffff8810343bf2f0] schedule at ffffffff814dabd9 #1 [ffff8810343bf3b8] nfs_wait_bit_killable at ffffffffa038fc04 [nfs] #2 [ffff8810343bf3c8] __wait_on_bit at ffffffff814dbc2f #3 [ffff8810343bf418] out_of_line_wait_on_bit at ffffffff814dbcd8 #4 [ffff8810343bf488] nfs_commit_inode at ffffffffa039e0c1 [nfs] #5 [ffff8810343bf4f8] nfs_release_page at ffffffffa038bef6 [nfs] #6 [ffff8810343bf528] try_to_release_page at ffffffff8110c670 #7 [ffff8810343bf538] shrink_page_list.clone.0 at ffffffff81126271 #8 [ffff8810343bf668] shrink_inactive_list at ffffffff81126638 #9 [ffff8810343bf818] shrink_zone at ffffffff8112788f #10 [ffff8810343bf8c8] do_try_to_free_pages at ffffffff81127b1e #11 [ffff8810343bf958] try_to_free_pages at ffffffff8112812f #12 [ffff8810343bfa08] __alloc_pages_nodemask at ffffffff8111fdad #13 [ffff8810343bfb28] kmem_getpages at ffffffff81159942 #14 [ffff8810343bfb58] fallback_alloc at ffffffff8115a55a #15 [ffff8810343bfbd8] ____cache_alloc_node at ffffffff8115a2d9 #16 [ffff8810343bfc38] kmem_cache_alloc at ffffffff8115b09b #17 [ffff8810343bfc78] sk_prot_alloc at ffffffff81411808 #18 [ffff8810343bfcb8] sk_alloc at ffffffff8141197c #19 [ffff8810343bfce8] inet_create at ffffffff81483ba6 #20 [ffff8810343bfd38] __sock_create at ffffffff8140b4a7 #21 [ffff8810343bfd98] xs_create_sock at ffffffffa01f649b [sunrpc] #22 [ffff8810343bfdd8] xs_tcp_setup_socket at ffffffffa01f6965 [sunrpc] #23 [ffff8810343bfe38] worker_thread at ffffffff810887d0 #24 [ffff8810343bfee8] kthread at ffffffff8108dd96 #25 [ffff8810343bff48] kernel_thread at ffffffff8100c1ca rpciod is trying to allocate memory for a new socket to talk to the server. The VM ends up calling ->releasepage to get more memory, and it tries to do a blocking commit. That commit can't succeed however without a connected socket, so we deadlock. Fix this by setting PF_FSTRANS on the workqueue task prior to doing the socket allocation, and having nfs_release_page check for that flag when deciding whether to do a commit call. Also, set PF_FSTRANS unconditionally in rpc_async_schedule since that function can also do allocations sometimes. Signed-off-by: Jeff Layton Signed-off-by: Trond Myklebust Signed-off-by: Greg Kroah-Hartman

nfs: don't open in ->d_revalidate

2012-06-01T16:12:02Z

NFSv4 can't do reliable opens in d_revalidate, since it cannot know whether a mount needs to be followed or not. It does check d_mountpoint() on the dentry, which can result in a weird error if the VFS found that the mount does not in fact need to be followed, e.g.: # mount --bind /mnt/nfs /mnt/nfs-clone # echo something > /mnt/nfs/tmp/bar # echo x > /tmp/file # mount --bind /tmp/file /mnt/nfs-clone/tmp/bar # cat /mnt/nfs/tmp/bar cat: /mnt/nfs/tmp/bar: Not a directory Which should, by any sane filesystem, result in "something" being printed. So instead do the open in f_op->open() and in the unlikely case that the cached dentry turned out to be invalid, drop the dentry and return EOPENSTALE to let the VFS retry. Signed-off-by: Miklos Szeredi CC: Trond Myklebust Signed-off-by: Al Viro

NFSv4.1 add nfs_inode book keeping for mdsthreshold

2012-05-24T20:15:48Z

Keep track of the number of bytes read or written via buffered, direct, and mem-mapped i/o for use by mdsthreshold size_io hints. Signed-off-by: Andy Adamson Signed-off-by: Trond Myklebust

NFS: Don't do a full flush to disk on close() if we hold a delegation

2012-05-08T16:53:21Z

If we hold a delegation then we know that it should be safe to continue to cache the data beyond the close(). However since the process that wrote the data may die after close(), we may still want to send the data to server before those RPCSEC_GSS credentials expire. We therefore compromise by starting writeback to the server, but don't wait for completion. Signed-off-by: Trond Myklebust

Merge tag 'split-asm_system_h-for-linus-20120328' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-asm_system

2012-03-28T22:58:21Z

Pull "Disintegrate and delete asm/system.h" from David Howells: "Here are a bunch of patches to disintegrate asm/system.h into a set of separate bits to relieve the problem of circular inclusion dependencies. I've built all the working defconfigs from all the arches that I can and made sure that they don't break. The reason for these patches is that I recently encountered a circular dependency problem that came about when I produced some patches to optimise get_order() by rewriting it to use ilog2(). This uses bitops - and on the SH arch asm/bitops.h drags in asm-generic/get_order.h by a circuituous route involving asm/system.h. The main difficulty seems to be asm/system.h. It holds a number of low level bits with no/few dependencies that are commonly used (eg. memory barriers) and a number of bits with more dependencies that aren't used in many places (eg. switch_to()). These patches break asm/system.h up into the following core pieces: (1) asm/barrier.h Move memory barriers here. This already done for MIPS and Alpha. (2) asm/switch_to.h Move switch_to() and related stuff here. (3) asm/exec.h Move arch_align_stack() here. Other process execution related bits could perhaps go here from asm/processor.h. (4) asm/cmpxchg.h Move xchg() and cmpxchg() here as they're full word atomic ops and frequently used by atomic_xchg() and atomic_cmpxchg(). (5) asm/bug.h Move die() and related bits. (6) asm/auxvec.h Move AT_VECTOR_SIZE_ARCH here. Other arch headers are created as needed on a per-arch basis." Fixed up some conflicts from other header file cleanups and moving code around that has happened in the meantime, so David's testing is somewhat weakened by that. We'll find out anything that got broken and fix it.. * tag 'split-asm_system_h-for-linus-20120328' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-asm_system: (38 commits) Delete all instances of asm/system.h Remove all #inclusions of asm/system.h Add #includes needed to permit the removal of asm/system.h Move all declarations of free_initmem() to linux/mm.h Disintegrate asm/system.h for OpenRISC Split arch_align_stack() out from asm-generic/system.h Split the switch_to() wrapper out of asm-generic/system.h Move the asm-generic/system.h xchg() implementation to asm-generic/cmpxchg.h Create asm-generic/barrier.h Make asm-generic/cmpxchg.h #include asm-generic/cmpxchg-local.h Disintegrate asm/system.h for Xtensa Disintegrate asm/system.h for Unicore32 [based on ver #3, changed by gxt] Disintegrate asm/system.h for Tile Disintegrate asm/system.h for Sparc Disintegrate asm/system.h for SH Disintegrate asm/system.h for Score Disintegrate asm/system.h for S390 Disintegrate asm/system.h for PowerPC Disintegrate asm/system.h for PA-RISC Disintegrate asm/system.h for MN10300 ...

Remove all #inclusions of asm/system.h

2012-03-28T17:30:03Z

Remove all #inclusions of asm/system.h preparatory to splitting and killing it. Performed with the following command: perl -p -i -e 's!^#\s*include\s*.*\n!!' `grep -Irl '^#\s*include\s*' *` Signed-off-by: David Howells

NFS: Ensure that mmapped pages remain stable during writeback

2012-02-01T00:28:08Z

Ensure that nfs_vm_page_mkwrite() waits for the page writeback to complete before the application is allowed to modify page contents. The main reason for wanting to do this in NFS is to ensure that the server doesn't get confused if we have to resend the RPC request due to a dropped/missed reply. Signed-off-by: Trond Myklebust

NFS - fix recent breakage to NFS error handling.

2012-01-05T15:42:39Z

From c6d615d2b97fe305cbf123a8751ced859dca1d5e Mon Sep 17 00:00:00 2001 From: NeilBrown Date: Wed, 16 Nov 2011 09:39:05 +1100 Subject: [PATCH] NFS - fix recent breakage to NFS error handling. commit 02c24a82187d5a628c68edfe71ae60dc135cd178 made a small and presumably unintended change to write error handling in NFS. Previously an error from filemap_write_and_wait_range would only be of interest if nfs_file_fsync did not return an error. After this commit, an error from filemap_write_and_wait_range would mean that (the rest of) nfs_file_fsync would not even be called. This means that: 1/ you are more likely to see EIO than e.g. EDQUOT or ENOSPC. 2/ NFS_CONTEXT_ERROR_WRITE remains set for longer so more writes are synchronous. This patch restores previous behaviour. Cc: stable@kernel.org Cc: Josef Bacik Cc: Jan Kara Cc: Al Viro Signed-off-by: NeilBrown Signed-off-by: Trond Myklebust

NFS: Fix a regression in nfs_file_llseek()

2011-12-15T23:44:36Z

After commit 06222e491e663dac939f04b125c9dc52126a75c4 (fs: handle SEEK_HOLE/SEEK_DATA properly in all fs's that define their own llseek) the behaviour of llseek() was changed so that it always revalidates the file size. The bug appears to be due to a logic error in the afore-mentioned commit, which always evaluates to 'true'. Reported-by: Roel Kluin Signed-off-by: Trond Myklebust Cc: stable@vger.kernel.org [>=3.1]

nfs: move nfs_file_operations declaration to bottom of file.c (try #2)

2011-11-04T20:39:11Z

...a remove a set of forward declarations. Signed-off-by: Jeff Layton Signed-off-by: Trond Myklebust