Benny Halevy e518f0560a nfsd: take file and mnt write in nfs4_upgrade_open ... testing with newpynfs revealed this warning: Jul 3 07:32:50 buml kernel: writeable file with no mnt_want_write() Jul 3 07:32:50 buml kernel: ------------[ cut here ]------------ Jul 3 07:32:50 buml kernel: WARNING: at /usr0/export/dev/bhalevy/git/linux-pnfs-bh-nfs41/include/linux/fs.h:855 drop_file_write_access+0x6b/0x7e() Jul 3 07:32:50 buml kernel: Modules linked in: nfsd auth_rpcgss exportfs nfs lockd nfs_acl sunrpc Jul 3 07:32:50 buml kernel: Call Trace: Jul 3 07:32:50 buml kernel: 6eaadc88: [<6002f471>] warn_on_slowpath+0x54/0x8e Jul 3 07:32:50 buml kernel: 6eaadcc8: [<601b790d>] printk+0xa0/0x793 Jul 3 07:32:50 buml kernel: 6eaadd38: [<601b6205>] __mutex_lock_slowpath+0x1db/0x1ea Jul 3 07:32:50 buml kernel: 6eaadd68: [<7107d4d5>] nfs4_preprocess_seqid_op+0x2a6/0x31c [nfsd] Jul 3 07:32:50 buml kernel: 6eaadda8: [<60078dc9>] drop_file_write_access+0x6b/0x7e Jul 3 07:32:50 buml kernel: 6eaaddc8: [<710804e4>] nfsd4_open_downgrade+0x114/0x1de [nfsd] Jul 3 07:32:50 buml kernel: 6eaade08: [<71076215>] nfsd4_proc_compound+0x1ba/0x2dc [nfsd] Jul 3 07:32:50 buml kernel: 6eaade48: [<71068221>] nfsd_dispatch+0xe5/0x1c2 [nfsd] Jul 3 07:32:50 buml kernel: 6eaade88: [<71312f81>] svc_process+0x3fd/0x714 [sunrpc] Jul 3 07:32:50 buml kernel: 6eaadea8: [<60039a81>] kernel_sigprocmask+0xf3/0x100 Jul 3 07:32:50 buml kernel: 6eaadee8: [<7106874b>] nfsd+0x182/0x29b [nfsd] Jul 3 07:32:50 buml kernel: 6eaadf48: [<60021cc9>] run_kernel_thread+0x41/0x4a Jul 3 07:32:50 buml kernel: 6eaadf58: [<710685c9>] nfsd+0x0/0x29b [nfsd] Jul 3 07:32:50 buml kernel: 6eaadf98: [<60021cb0>] run_kernel_thread+0x28/0x4a Jul 3 07:32:50 buml kernel: 6eaadfc8: [<60013829>] new_thread_handler+0x72/0x9c Jul 3 07:32:50 buml kernel: Jul 3 07:32:50 buml kernel: ---[ end trace 2426dd7cb2fba3bf ]--- Bruce Fields suggested this (Thanks!): maybe we need to be doing a mnt_want_write on open_upgrade and mnt_put_write on downgrade? This patch adds a call to mnt_want_write and file_take_write (which is doing the actual work). The counter-calls mnt_drop_write a file_release_write are now being properly called by drop_file_write_access in the exact path printed by the warning above. Signed-off-by: Benny Halevy <bhalevy@panasas.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>		2008-07-07 15:23:34 -04:00
..
auth.c	nfsd: fix sparse warnings	2008-04-23 16:13:39 -04:00
auth.h
export.c	IPv6 support for NFS server export caches	2008-04-23 16:13:36 -04:00
lockd.c	nfsd: rename MAY_ flags	2008-06-23 13:02:50 -04:00
Makefile
nfs2acl.c	nfsd: rename MAY_ flags	2008-06-23 13:02:50 -04:00
nfs3acl.c	nfsd: rename MAY_ flags	2008-06-23 13:02:50 -04:00
nfs3proc.c	nfsd: rename MAY_ flags	2008-06-23 13:02:50 -04:00
nfs3xdr.c	Use struct path in struct svc_export	2008-02-14 21:17:08 -08:00
nfs4acl.c
nfs4callback.c	nfsd: reorder printk in do_probe_callback to avoid use-after-free	2008-05-18 19:13:07 -04:00
nfs4idmap.c	nfsd: fix sparse warnings	2008-04-23 16:13:39 -04:00
nfs4proc.c	nfsd: dprint operation names	2008-07-02 19:03:19 -04:00
nfs4recover.c	[PATCH] r/o bind mounts: get callers of vfs_mknod/create/mkdir()	2008-04-19 00:25:34 -04:00
nfs4state.c	nfsd: take file and mnt write in nfs4_upgrade_open	2008-07-07 15:23:34 -04:00
nfs4xdr.c	nfsd: tabulate nfs4 xdr encoding functions	2008-07-04 16:21:30 -04:00
nfscache.c
nfsctl.c	knfsd: clean up nfsd filesystem interfaces	2008-06-23 13:02:49 -04:00
nfsfh.c	nfsd: fix spurious EACCESS in reconnect_path()	2008-06-30 15:24:11 -04:00
nfsproc.c	nfsd: rename MAY_ flags	2008-06-23 13:02:50 -04:00
nfssvc.c	nfsd: treat all shutdown signals as equivalent	2008-06-30 15:27:47 -04:00
nfsxdr.c	Use struct path in struct svc_export	2008-02-14 21:17:08 -08:00
stats.c
vfs.c	nfsd: clean up mnt_want_write calls	2008-07-01 15:22:03 -04:00