linux/fs/9p/fid.h
Joakim Sindholt 4e5d208cc9
fs/9p: fix the cache always being enabled on files with qid flags
I'm not sure why this check was ever here. After updating to 6.6 I
suddenly found caching had been turned on by default and neither
cache=none nor the new directio would turn it off. After walking through
the new code very manually I realized that it's because the caching has
to be, in effect, turned off explicitly by setting P9L_DIRECT and
whenever a file has a flag, in my case QTAPPEND, it doesn't get set.

Setting aside QTDIR which seems to ignore the new fid->mode entirely,
the rest of these either should be subject to the same cache rules as
every other QTFILE or perhaps very explicitly not cached in the case of
QTAUTH.

Signed-off-by: Joakim Sindholt <opensource@zhasha.com>
Signed-off-by: Eric Van Hensbergen <ericvh@kernel.org>
2024-03-28 15:10:29 +00:00

62 lines
1.8 KiB
C

/* SPDX-License-Identifier: GPL-2.0-only */
/*
* V9FS FID Management
*
* Copyright (C) 2005 by Eric Van Hensbergen <ericvh@gmail.com>
*/
#ifndef FS_9P_FID_H
#define FS_9P_FID_H
#include <linux/list.h>
#include "v9fs.h"
struct p9_fid *v9fs_fid_find_inode(struct inode *inode, bool want_writeable,
kuid_t uid, bool any);
struct p9_fid *v9fs_fid_lookup(struct dentry *dentry);
static inline struct p9_fid *v9fs_parent_fid(struct dentry *dentry)
{
return v9fs_fid_lookup(dentry->d_parent);
}
void v9fs_fid_add(struct dentry *dentry, struct p9_fid **fid);
void v9fs_open_fid_add(struct inode *inode, struct p9_fid **fid);
static inline struct p9_fid *clone_fid(struct p9_fid *fid)
{
return IS_ERR(fid) ? fid : p9_client_walk(fid, 0, NULL, 1);
}
static inline struct p9_fid *v9fs_fid_clone(struct dentry *dentry)
{
struct p9_fid *fid, *nfid;
fid = v9fs_fid_lookup(dentry);
if (!fid || IS_ERR(fid))
return fid;
nfid = clone_fid(fid);
p9_fid_put(fid);
return nfid;
}
/**
* v9fs_fid_addmodes - add cache flags to fid mode (for client use only)
* @fid: fid to augment
* @s_flags: session info mount flags
* @s_cache: session info cache flags
* @f_flags: unix open flags
*
* make sure mode reflects flags of underlying mounts
* also qid.version == 0 reflects a synthetic or legacy file system
* NOTE: these are set after open so only reflect 9p client not
* underlying file system on server.
*/
static inline void v9fs_fid_add_modes(struct p9_fid *fid, unsigned int s_flags,
unsigned int s_cache, unsigned int f_flags)
{
if ((!s_cache) ||
((fid->qid.version == 0) && !(s_flags & V9FS_IGNORE_QV)) ||
(s_flags & V9FS_DIRECT_IO) || (f_flags & O_DIRECT)) {
fid->mode |= P9L_DIRECT; /* no read or write cache */
} else if ((!(s_cache & CACHE_WRITEBACK)) ||
(f_flags & O_DSYNC) || (s_flags & V9FS_SYNC)) {
fid->mode |= P9L_NOWRITECACHE;
}
}
#endif