2005-09-09 14:04:24 -06:00
|
|
|
/*
|
|
|
|
* V9FS FID Management
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*
|
2007-10-17 13:31:07 -06:00
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* Copyright (C) 2007 by Latchesar Ionkov <lucho@ionkov.net>
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2006-03-02 03:54:33 -07:00
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* Copyright (C) 2005, 2006 by Eric Van Hensbergen <ericvh@gmail.com>
|
2005-09-09 14:04:24 -06:00
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*
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* This program is free software; you can redistribute it and/or modify
|
2006-03-25 04:07:28 -07:00
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* it under the terms of the GNU General Public License version 2
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* as published by the Free Software Foundation.
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2005-09-09 14:04:24 -06:00
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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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#include <linux/module.h>
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#include <linux/errno.h>
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#include <linux/fs.h>
|
include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.
percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.
http://userweb.kernel.org/~tj/misc/slabh-sweep.py
The script does the followings.
* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.
* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.
* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.
The conversion was done in the following steps.
1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.
2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.
3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.
4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.
5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.
6. percpu.h was updated not to include slab.h.
7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).
* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig
8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.
Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.
Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-24 02:04:11 -06:00
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|
|
#include <linux/slab.h>
|
2006-10-18 11:55:46 -06:00
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#include <linux/sched.h>
|
2005-09-09 14:04:24 -06:00
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#include <linux/idr.h>
|
2007-07-10 16:57:28 -06:00
|
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#include <net/9p/9p.h>
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|
#include <net/9p/client.h>
|
2005-09-09 14:04:24 -06:00
|
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|
#include "v9fs.h"
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|
|
#include "v9fs_vfs.h"
|
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|
#include "fid.h"
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|
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/**
|
2007-10-17 13:31:07 -06:00
|
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|
* v9fs_fid_add - add a fid to a dentry
|
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* @dentry: dentry that the fid is being added to
|
2005-09-09 14:04:24 -06:00
|
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|
* @fid: fid to add
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|
|
*
|
|
|
|
*/
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|
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|
2007-07-10 16:57:28 -06:00
|
|
|
int v9fs_fid_add(struct dentry *dentry, struct p9_fid *fid)
|
2005-09-09 14:04:24 -06:00
|
|
|
{
|
2007-07-10 16:57:28 -06:00
|
|
|
struct v9fs_dentry *dent;
|
2005-09-09 14:04:24 -06:00
|
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|
|
2007-07-10 16:57:28 -06:00
|
|
|
P9_DPRINTK(P9_DEBUG_VFS, "fid %d dentry %s\n",
|
2008-12-19 15:47:40 -07:00
|
|
|
fid->fid, dentry->d_name.name);
|
2005-09-09 14:04:24 -06:00
|
|
|
|
2007-07-10 16:57:28 -06:00
|
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|
dent = dentry->d_fsdata;
|
|
|
|
if (!dent) {
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|
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|
dent = kmalloc(sizeof(struct v9fs_dentry), GFP_KERNEL);
|
|
|
|
if (!dent)
|
|
|
|
return -ENOMEM;
|
2005-09-09 14:04:24 -06:00
|
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|
|
2007-07-10 16:57:28 -06:00
|
|
|
spin_lock_init(&dent->lock);
|
|
|
|
INIT_LIST_HEAD(&dent->fidlist);
|
|
|
|
dentry->d_fsdata = dent;
|
2005-09-09 14:04:24 -06:00
|
|
|
}
|
|
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|
|
2007-07-10 16:57:28 -06:00
|
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|
spin_lock(&dent->lock);
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|
|
|
list_add(&fid->dlist, &dent->fidlist);
|
|
|
|
spin_unlock(&dent->lock);
|
2005-09-09 14:04:24 -06:00
|
|
|
|
2007-07-10 16:57:28 -06:00
|
|
|
return 0;
|
2005-09-09 14:04:24 -06:00
|
|
|
}
|
|
|
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|
|
|
/**
|
2007-10-17 13:31:07 -06:00
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|
* v9fs_fid_find - retrieve a fid that belongs to the specified uid
|
2005-09-09 14:04:24 -06:00
|
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|
* @dentry: dentry to look for fid in
|
2007-10-17 13:31:07 -06:00
|
|
|
* @uid: return fid that belongs to the specified user
|
|
|
|
* @any: if non-zero, return any fid associated with the dentry
|
2005-09-09 14:04:24 -06:00
|
|
|
*
|
|
|
|
*/
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|
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|
2007-10-17 13:31:07 -06:00
|
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|
static struct p9_fid *v9fs_fid_find(struct dentry *dentry, u32 uid, int any)
|
2005-09-09 14:04:24 -06:00
|
|
|
{
|
2007-07-10 16:57:28 -06:00
|
|
|
struct v9fs_dentry *dent;
|
2007-10-17 13:31:07 -06:00
|
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|
struct p9_fid *fid, *ret;
|
|
|
|
|
|
|
|
P9_DPRINTK(P9_DEBUG_VFS, " dentry: %s (%p) uid %d any %d\n",
|
2008-12-19 15:47:40 -07:00
|
|
|
dentry->d_name.name, dentry, uid, any);
|
2007-10-17 13:31:07 -06:00
|
|
|
dent = (struct v9fs_dentry *) dentry->d_fsdata;
|
|
|
|
ret = NULL;
|
|
|
|
if (dent) {
|
|
|
|
spin_lock(&dent->lock);
|
|
|
|
list_for_each_entry(fid, &dent->fidlist, dlist) {
|
|
|
|
if (any || fid->uid == uid) {
|
|
|
|
ret = fid;
|
|
|
|
break;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
spin_unlock(&dent->lock);
|
|
|
|
}
|
2007-07-10 16:57:28 -06:00
|
|
|
|
2007-10-17 13:31:07 -06:00
|
|
|
return ret;
|
2007-07-10 16:57:28 -06:00
|
|
|
}
|
2005-09-09 14:04:24 -06:00
|
|
|
|
2010-06-30 07:48:50 -06:00
|
|
|
/*
|
|
|
|
* We need to hold v9ses->rename_sem as long as we hold references
|
|
|
|
* to returned path array. Array element contain pointers to
|
|
|
|
* dentry names.
|
|
|
|
*/
|
|
|
|
static int build_path_from_dentry(struct v9fs_session_info *v9ses,
|
|
|
|
struct dentry *dentry, char ***names)
|
|
|
|
{
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|
|
|
int n = 0, i;
|
|
|
|
char **wnames;
|
|
|
|
struct dentry *ds;
|
|
|
|
|
|
|
|
for (ds = dentry; !IS_ROOT(ds); ds = ds->d_parent)
|
|
|
|
n++;
|
|
|
|
|
|
|
|
wnames = kmalloc(sizeof(char *) * n, GFP_KERNEL);
|
|
|
|
if (!wnames)
|
|
|
|
goto err_out;
|
|
|
|
|
|
|
|
for (ds = dentry, i = (n-1); i >= 0; i--, ds = ds->d_parent)
|
|
|
|
wnames[i] = (char *)ds->d_name.name;
|
|
|
|
|
|
|
|
*names = wnames;
|
|
|
|
return n;
|
|
|
|
err_out:
|
|
|
|
return -ENOMEM;
|
|
|
|
}
|
|
|
|
|
2011-02-28 04:34:11 -07:00
|
|
|
static struct p9_fid *v9fs_fid_lookup_with_uid(struct dentry *dentry,
|
|
|
|
uid_t uid, int any)
|
2007-01-26 01:57:06 -07:00
|
|
|
{
|
2010-06-30 07:48:50 -06:00
|
|
|
struct dentry *ds;
|
2007-10-17 13:31:07 -06:00
|
|
|
char **wnames, *uname;
|
2011-02-28 04:34:11 -07:00
|
|
|
int i, n, l, clone, access;
|
|
|
|
struct v9fs_session_info *v9ses;
|
|
|
|
struct p9_fid *fid, *old_fid = NULL;
|
2007-10-17 13:31:07 -06:00
|
|
|
|
|
|
|
v9ses = v9fs_inode2v9ses(dentry->d_inode);
|
|
|
|
access = v9ses->flags & V9FS_ACCESS_MASK;
|
|
|
|
fid = v9fs_fid_find(dentry, uid, any);
|
|
|
|
if (fid)
|
|
|
|
return fid;
|
2010-06-30 07:48:50 -06:00
|
|
|
/*
|
|
|
|
* we don't have a matching fid. To do a TWALK we need
|
|
|
|
* parent fid. We need to prevent rename when we want to
|
|
|
|
* look at the parent.
|
|
|
|
*/
|
|
|
|
down_read(&v9ses->rename_sem);
|
2007-10-17 13:31:07 -06:00
|
|
|
ds = dentry->d_parent;
|
|
|
|
fid = v9fs_fid_find(ds, uid, any);
|
2010-06-30 07:48:50 -06:00
|
|
|
if (fid) {
|
|
|
|
/* Found the parent fid do a lookup with that */
|
|
|
|
fid = p9_client_walk(fid, 1, (char **)&dentry->d_name.name, 1);
|
|
|
|
goto fid_out;
|
|
|
|
}
|
|
|
|
up_read(&v9ses->rename_sem);
|
2007-10-17 13:31:07 -06:00
|
|
|
|
2010-06-30 07:48:50 -06:00
|
|
|
/* start from the root and try to do a lookup */
|
|
|
|
fid = v9fs_fid_find(dentry->d_sb->s_root, uid, any);
|
|
|
|
if (!fid) {
|
|
|
|
/* the user is not attached to the fs yet */
|
|
|
|
if (access == V9FS_ACCESS_SINGLE)
|
|
|
|
return ERR_PTR(-EPERM);
|
2007-10-17 13:31:07 -06:00
|
|
|
|
2010-06-30 07:48:50 -06:00
|
|
|
if (v9fs_proto_dotu(v9ses) || v9fs_proto_dotl(v9ses))
|
|
|
|
uname = NULL;
|
|
|
|
else
|
|
|
|
uname = v9ses->uname;
|
2007-10-17 13:31:07 -06:00
|
|
|
|
2010-06-30 07:48:50 -06:00
|
|
|
fid = p9_client_attach(v9ses->clnt, NULL, uname, uid,
|
|
|
|
v9ses->aname);
|
|
|
|
if (IS_ERR(fid))
|
|
|
|
return fid;
|
2007-10-17 13:31:07 -06:00
|
|
|
|
2010-06-30 07:48:50 -06:00
|
|
|
v9fs_fid_add(dentry->d_sb->s_root, fid);
|
|
|
|
}
|
|
|
|
/* If we are root ourself just return that */
|
|
|
|
if (dentry->d_sb->s_root == dentry)
|
2007-10-17 13:31:07 -06:00
|
|
|
return fid;
|
2010-06-30 07:48:50 -06:00
|
|
|
/*
|
|
|
|
* Do a multipath walk with attached root.
|
|
|
|
* When walking parent we need to make sure we
|
|
|
|
* don't have a parallel rename happening
|
|
|
|
*/
|
|
|
|
down_read(&v9ses->rename_sem);
|
|
|
|
n = build_path_from_dentry(v9ses, dentry, &wnames);
|
|
|
|
if (n < 0) {
|
|
|
|
fid = ERR_PTR(n);
|
|
|
|
goto err_out;
|
|
|
|
}
|
2007-10-17 13:31:07 -06:00
|
|
|
clone = 1;
|
|
|
|
i = 0;
|
|
|
|
while (i < n) {
|
|
|
|
l = min(n - i, P9_MAXWELEM);
|
2010-06-30 07:48:50 -06:00
|
|
|
/*
|
|
|
|
* We need to hold rename lock when doing a multipath
|
|
|
|
* walk to ensure none of the patch component change
|
|
|
|
*/
|
2007-10-17 13:31:07 -06:00
|
|
|
fid = p9_client_walk(fid, l, &wnames[i], clone);
|
2008-02-06 18:25:08 -07:00
|
|
|
if (IS_ERR(fid)) {
|
2010-03-19 06:47:26 -06:00
|
|
|
if (old_fid) {
|
|
|
|
/*
|
|
|
|
* If we fail, clunk fid which are mapping
|
|
|
|
* to path component and not the last component
|
|
|
|
* of the path.
|
|
|
|
*/
|
|
|
|
p9_client_clunk(old_fid);
|
|
|
|
}
|
2007-10-17 13:31:07 -06:00
|
|
|
kfree(wnames);
|
2010-06-30 07:48:50 -06:00
|
|
|
goto err_out;
|
2007-10-17 13:31:07 -06:00
|
|
|
}
|
2010-03-19 06:47:26 -06:00
|
|
|
old_fid = fid;
|
2007-10-17 13:31:07 -06:00
|
|
|
i += l;
|
|
|
|
clone = 0;
|
|
|
|
}
|
|
|
|
kfree(wnames);
|
2010-06-30 07:48:50 -06:00
|
|
|
fid_out:
|
2010-08-04 10:27:45 -06:00
|
|
|
if (!IS_ERR(fid))
|
|
|
|
v9fs_fid_add(dentry, fid);
|
2010-06-30 07:48:50 -06:00
|
|
|
err_out:
|
|
|
|
up_read(&v9ses->rename_sem);
|
2007-07-10 16:57:28 -06:00
|
|
|
return fid;
|
2007-01-26 01:57:06 -07:00
|
|
|
}
|
2007-10-17 13:31:07 -06:00
|
|
|
|
2011-02-28 04:34:11 -07:00
|
|
|
/**
|
|
|
|
* v9fs_fid_lookup - lookup for a fid, try to walk if not found
|
|
|
|
* @dentry: dentry to look for fid in
|
|
|
|
*
|
|
|
|
* Look for a fid in the specified dentry for the current user.
|
|
|
|
* If no fid is found, try to create one walking from a fid from the parent
|
|
|
|
* dentry (if it has one), or the root dentry. If the user haven't accessed
|
|
|
|
* the fs yet, attach now and walk from the root.
|
|
|
|
*/
|
|
|
|
|
|
|
|
struct p9_fid *v9fs_fid_lookup(struct dentry *dentry)
|
|
|
|
{
|
|
|
|
uid_t uid;
|
|
|
|
int any, access;
|
|
|
|
struct v9fs_session_info *v9ses;
|
|
|
|
|
|
|
|
v9ses = v9fs_inode2v9ses(dentry->d_inode);
|
|
|
|
access = v9ses->flags & V9FS_ACCESS_MASK;
|
|
|
|
switch (access) {
|
|
|
|
case V9FS_ACCESS_SINGLE:
|
|
|
|
case V9FS_ACCESS_USER:
|
|
|
|
case V9FS_ACCESS_CLIENT:
|
|
|
|
uid = current_fsuid();
|
|
|
|
any = 0;
|
|
|
|
break;
|
|
|
|
|
|
|
|
case V9FS_ACCESS_ANY:
|
|
|
|
uid = v9ses->uid;
|
|
|
|
any = 1;
|
|
|
|
break;
|
|
|
|
|
|
|
|
default:
|
|
|
|
uid = ~0;
|
|
|
|
any = 0;
|
|
|
|
break;
|
|
|
|
}
|
|
|
|
return v9fs_fid_lookup_with_uid(dentry, uid, any);
|
|
|
|
}
|
|
|
|
|
2007-10-17 13:31:07 -06:00
|
|
|
struct p9_fid *v9fs_fid_clone(struct dentry *dentry)
|
|
|
|
{
|
|
|
|
struct p9_fid *fid, *ret;
|
|
|
|
|
|
|
|
fid = v9fs_fid_lookup(dentry);
|
|
|
|
if (IS_ERR(fid))
|
|
|
|
return fid;
|
|
|
|
|
|
|
|
ret = p9_client_walk(fid, 0, NULL, 1);
|
|
|
|
return ret;
|
|
|
|
}
|
2011-02-28 04:33:57 -07:00
|
|
|
|
2011-02-28 04:34:11 -07:00
|
|
|
static struct p9_fid *v9fs_fid_clone_with_uid(struct dentry *dentry, uid_t uid)
|
|
|
|
{
|
|
|
|
struct p9_fid *fid, *ret;
|
|
|
|
|
|
|
|
fid = v9fs_fid_lookup_with_uid(dentry, uid, 0);
|
|
|
|
if (IS_ERR(fid))
|
|
|
|
return fid;
|
|
|
|
|
|
|
|
ret = p9_client_walk(fid, 0, NULL, 1);
|
|
|
|
return ret;
|
|
|
|
}
|
2011-02-28 04:33:57 -07:00
|
|
|
|
|
|
|
struct p9_fid *v9fs_writeback_fid(struct dentry *dentry)
|
|
|
|
{
|
|
|
|
int err;
|
|
|
|
struct p9_fid *fid;
|
|
|
|
|
2011-02-28 04:34:11 -07:00
|
|
|
fid = v9fs_fid_clone_with_uid(dentry, 0);
|
2011-02-28 04:33:57 -07:00
|
|
|
if (IS_ERR(fid))
|
|
|
|
goto error_out;
|
|
|
|
/*
|
|
|
|
* writeback fid will only be used to write back the
|
|
|
|
* dirty pages. We always request for the open fid in read-write
|
|
|
|
* mode so that a partial page write which result in page
|
|
|
|
* read can work.
|
|
|
|
*/
|
|
|
|
err = p9_client_open(fid, O_RDWR);
|
|
|
|
if (err < 0) {
|
|
|
|
p9_client_clunk(fid);
|
|
|
|
fid = ERR_PTR(err);
|
|
|
|
goto error_out;
|
|
|
|
}
|
|
|
|
error_out:
|
|
|
|
return fid;
|
|
|
|
}
|