6a3124a394
In order to assure atomic create+open v9fs stores the open fid produced by v9fs_vfs_create in the dentry, from where v9fs_file_open retrieves it and associates it with the open file. This patch modifies v9fs to use nameidata.intent.open values to do the atomic create+open. Signed-off-by: Latchesar Ionkov <lucho@ionkov.net> Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
55 lines
2.2 KiB
C
55 lines
2.2 KiB
C
/*
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* V9FS VFS extensions.
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*
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* Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
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* Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to:
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* Free Software Foundation
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* 51 Franklin Street, Fifth Floor
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* Boston, MA 02111-1301 USA
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*
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*/
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/* plan9 semantics are that created files are implicitly opened.
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* But linux semantics are that you call create, then open.
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* the plan9 approach is superior as it provides an atomic
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* open.
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* we track the create fid here. When the file is opened, if fidopen is
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* non-zero, we use the fid and can skip some steps.
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* there may be a better way to do this, but I don't know it.
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* one BAD way is to clunk the fid on create, then open it again:
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* you lose the atomicity of file open
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*/
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/* special case:
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* unlink calls remove, which is an implicit clunk. So we have to track
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* that kind of thing so that we don't try to clunk a dead fid.
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*/
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extern struct file_system_type v9fs_fs_type;
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extern struct address_space_operations v9fs_addr_operations;
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extern struct file_operations v9fs_file_operations;
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extern struct file_operations v9fs_dir_operations;
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extern struct dentry_operations v9fs_dentry_operations;
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struct inode *v9fs_get_inode(struct super_block *sb, int mode);
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ino_t v9fs_qid2ino(struct v9fs_qid *qid);
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void v9fs_stat2inode(struct v9fs_stat *, struct inode *, struct super_block *);
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int v9fs_dir_release(struct inode *inode, struct file *filp);
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int v9fs_file_open(struct inode *inode, struct file *file);
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void v9fs_inode2stat(struct inode *inode, struct v9fs_stat *stat);
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void v9fs_dentry_release(struct dentry *);
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int v9fs_uflags2omode(int uflags);
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