fs/9p/fid.h

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2 /*
   3  * V9FS FID Management
   4  *
   5  *  Copyright (C) 2005 by Eric Van Hensbergen <ericvh@gmail.com>
   6  */
   7 #ifndef FS_9P_FID_H
   8 #define FS_9P_FID_H
   9 #include <linux/list.h>
  10 #include "v9fs.h"
  11
  12 struct p9_fid *v9fs_fid_find_inode(struct inode *inode, bool want_writeable,
  13         kuid_t uid, bool any);
  14 struct p9_fid *v9fs_fid_lookup(struct dentry *dentry);
  15 static inline struct p9_fid *v9fs_parent_fid(struct dentry *dentry)
  16 {
  17         return v9fs_fid_lookup(dentry->d_parent);
  18 }
  19 void v9fs_fid_add(struct dentry *dentry, struct p9_fid **fid);
  20 void v9fs_open_fid_add(struct inode *inode, struct p9_fid **fid);
  21 static inline struct p9_fid *clone_fid(struct p9_fid *fid)
  22 {
  23         return IS_ERR(fid) ? fid :  p9_client_walk(fid, 0, NULL, 1);
  24 }
  25 static inline struct p9_fid *v9fs_fid_clone(struct dentry *dentry)
  26 {
  27         struct p9_fid *fid, *nfid;
  28
  29         fid = v9fs_fid_lookup(dentry);
  30         if (!fid || IS_ERR(fid))
  31                 return fid;
  32
  33         nfid = clone_fid(fid);
  34         p9_fid_put(fid);
  35         return nfid;
  36 }
  37 /**
  38  * v9fs_fid_addmodes - add cache flags to fid mode (for client use only)
  39  * @fid: fid to augment
  40  * @s_flags: session info mount flags
  41  * @s_cache: session info cache flags
  42  * @f_flags: unix open flags
  43  *
  44  * make sure mode reflects flags of underlying mounts
  45  * also qid.version == 0 reflects a synthetic or legacy file system
  46  * NOTE: these are set after open so only reflect 9p client not
  47  * underlying file system on server.
  48  */
  49 static inline void v9fs_fid_add_modes(struct p9_fid *fid, unsigned int s_flags,
  50         unsigned int s_cache, unsigned int f_flags)
  51 {
  52         if ((!s_cache) ||
  53            ((fid->qid.version == 0) && !(s_flags & V9FS_IGNORE_QV)) ||
  54            (s_flags & V9FS_DIRECT_IO) || (f_flags & O_DIRECT)) {
  55                 fid->mode |= P9L_DIRECT; /* no read or write cache */
  56         } else if ((!(s_cache & CACHE_WRITEBACK)) ||
  57                                 (f_flags & O_DSYNC) || (s_flags & V9FS_SYNC)) {
  58                 fid->mode |= P9L_NOWRITECACHE;
  59         }
  60 }
  61 #endif