android_kernel_sony_msm8994/fs/9p/vfs_inode.c
Latchesar Ionkov 41e5a6ac80 [PATCH] v9fs: signal handling fixes
Multiple races can happen when v9fs is interrupted by a signal and Tflush
message is sent to the server.  After v9fs sends Tflush it doesn't wait
until it receives Rflush, and possibly the response of the original
message.  This behavior may confuse v9fs what fids are allocated by the
file server.

This patch fixes the races and the fid allocation.

Signed-off-by: Latchesar Ionkov <lucho@ionkov.net>
Cc: Eric Van Hensbergen <ericvh@hera.kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-05-15 11:20:56 -07:00

1318 lines
28 KiB
C

/*
* linux/fs/9p/vfs_inode.c
*
* This file contains vfs inode ops for the 9P2000 protocol.
*
* Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
* Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2
* as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to:
* Free Software Foundation
* 51 Franklin Street, Fifth Floor
* Boston, MA 02111-1301 USA
*
*/
#include <linux/module.h>
#include <linux/errno.h>
#include <linux/fs.h>
#include <linux/file.h>
#include <linux/pagemap.h>
#include <linux/stat.h>
#include <linux/string.h>
#include <linux/smp_lock.h>
#include <linux/inet.h>
#include <linux/namei.h>
#include <linux/idr.h>
#include "debug.h"
#include "v9fs.h"
#include "9p.h"
#include "v9fs_vfs.h"
#include "fid.h"
static struct inode_operations v9fs_dir_inode_operations;
static struct inode_operations v9fs_dir_inode_operations_ext;
static struct inode_operations v9fs_file_inode_operations;
static struct inode_operations v9fs_symlink_inode_operations;
/**
* unixmode2p9mode - convert unix mode bits to plan 9
* @v9ses: v9fs session information
* @mode: mode to convert
*
*/
static int unixmode2p9mode(struct v9fs_session_info *v9ses, int mode)
{
int res;
res = mode & 0777;
if (S_ISDIR(mode))
res |= V9FS_DMDIR;
if (v9ses->extended) {
if (S_ISLNK(mode))
res |= V9FS_DMSYMLINK;
if (v9ses->nodev == 0) {
if (S_ISSOCK(mode))
res |= V9FS_DMSOCKET;
if (S_ISFIFO(mode))
res |= V9FS_DMNAMEDPIPE;
if (S_ISBLK(mode))
res |= V9FS_DMDEVICE;
if (S_ISCHR(mode))
res |= V9FS_DMDEVICE;
}
if ((mode & S_ISUID) == S_ISUID)
res |= V9FS_DMSETUID;
if ((mode & S_ISGID) == S_ISGID)
res |= V9FS_DMSETGID;
if ((mode & V9FS_DMLINK))
res |= V9FS_DMLINK;
}
return res;
}
/**
* p9mode2unixmode- convert plan9 mode bits to unix mode bits
* @v9ses: v9fs session information
* @mode: mode to convert
*
*/
static int p9mode2unixmode(struct v9fs_session_info *v9ses, int mode)
{
int res;
res = mode & 0777;
if ((mode & V9FS_DMDIR) == V9FS_DMDIR)
res |= S_IFDIR;
else if ((mode & V9FS_DMSYMLINK) && (v9ses->extended))
res |= S_IFLNK;
else if ((mode & V9FS_DMSOCKET) && (v9ses->extended)
&& (v9ses->nodev == 0))
res |= S_IFSOCK;
else if ((mode & V9FS_DMNAMEDPIPE) && (v9ses->extended)
&& (v9ses->nodev == 0))
res |= S_IFIFO;
else if ((mode & V9FS_DMDEVICE) && (v9ses->extended)
&& (v9ses->nodev == 0))
res |= S_IFBLK;
else
res |= S_IFREG;
if (v9ses->extended) {
if ((mode & V9FS_DMSETUID) == V9FS_DMSETUID)
res |= S_ISUID;
if ((mode & V9FS_DMSETGID) == V9FS_DMSETGID)
res |= S_ISGID;
}
return res;
}
int v9fs_uflags2omode(int uflags)
{
int ret;
ret = 0;
switch (uflags&3) {
default:
case O_RDONLY:
ret = V9FS_OREAD;
break;
case O_WRONLY:
ret = V9FS_OWRITE;
break;
case O_RDWR:
ret = V9FS_ORDWR;
break;
}
if (uflags & O_EXCL)
ret |= V9FS_OEXCL;
if (uflags & O_TRUNC)
ret |= V9FS_OTRUNC;
if (uflags & O_APPEND)
ret |= V9FS_OAPPEND;
return ret;
}
/**
* v9fs_blank_wstat - helper function to setup a 9P stat structure
* @v9ses: 9P session info (for determining extended mode)
* @wstat: structure to initialize
*
*/
static void
v9fs_blank_wstat(struct v9fs_wstat *wstat)
{
wstat->type = ~0;
wstat->dev = ~0;
wstat->qid.type = ~0;
wstat->qid.version = ~0;
*((long long *)&wstat->qid.path) = ~0;
wstat->mode = ~0;
wstat->atime = ~0;
wstat->mtime = ~0;
wstat->length = ~0;
wstat->name = NULL;
wstat->uid = NULL;
wstat->gid = NULL;
wstat->muid = NULL;
wstat->n_uid = ~0;
wstat->n_gid = ~0;
wstat->n_muid = ~0;
wstat->extension = NULL;
}
/**
* v9fs_get_inode - helper function to setup an inode
* @sb: superblock
* @mode: mode to setup inode with
*
*/
struct inode *v9fs_get_inode(struct super_block *sb, int mode)
{
struct inode *inode;
struct v9fs_session_info *v9ses = sb->s_fs_info;
dprintk(DEBUG_VFS, "super block: %p mode: %o\n", sb, mode);
inode = new_inode(sb);
if (inode) {
inode->i_mode = mode;
inode->i_uid = current->fsuid;
inode->i_gid = current->fsgid;
inode->i_blksize = sb->s_blocksize;
inode->i_blocks = 0;
inode->i_rdev = 0;
inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
inode->i_mapping->a_ops = &v9fs_addr_operations;
switch (mode & S_IFMT) {
case S_IFIFO:
case S_IFBLK:
case S_IFCHR:
case S_IFSOCK:
if(!v9ses->extended) {
dprintk(DEBUG_ERROR, "special files without extended mode\n");
return ERR_PTR(-EINVAL);
}
init_special_inode(inode, inode->i_mode,
inode->i_rdev);
break;
case S_IFREG:
inode->i_op = &v9fs_file_inode_operations;
inode->i_fop = &v9fs_file_operations;
break;
case S_IFLNK:
if(!v9ses->extended) {
dprintk(DEBUG_ERROR, "extended modes used w/o 9P2000.u\n");
return ERR_PTR(-EINVAL);
}
inode->i_op = &v9fs_symlink_inode_operations;
break;
case S_IFDIR:
inode->i_nlink++;
if(v9ses->extended)
inode->i_op = &v9fs_dir_inode_operations_ext;
else
inode->i_op = &v9fs_dir_inode_operations;
inode->i_fop = &v9fs_dir_operations;
break;
default:
dprintk(DEBUG_ERROR, "BAD mode 0x%x S_IFMT 0x%x\n",
mode, mode & S_IFMT);
return ERR_PTR(-EINVAL);
}
} else {
eprintk(KERN_WARNING, "Problem allocating inode\n");
return ERR_PTR(-ENOMEM);
}
return inode;
}
static int
v9fs_create(struct v9fs_session_info *v9ses, u32 pfid, char *name, u32 perm,
u8 mode, char *extension, u32 *fidp, struct v9fs_qid *qid, u32 *iounit)
{
u32 fid;
int err;
struct v9fs_fcall *fcall;
fid = v9fs_get_idpool(&v9ses->fidpool);
if (fid < 0) {
eprintk(KERN_WARNING, "no free fids available\n");
return -ENOSPC;
}
err = v9fs_t_walk(v9ses, pfid, fid, NULL, &fcall);
if (err < 0) {
PRINT_FCALL_ERROR("clone error", fcall);
if (fcall && fcall->id == RWALK)
goto clunk_fid;
else
goto put_fid;
}
kfree(fcall);
err = v9fs_t_create(v9ses, fid, name, perm, mode, extension, &fcall);
if (err < 0) {
PRINT_FCALL_ERROR("create fails", fcall);
goto clunk_fid;
}
if (iounit)
*iounit = fcall->params.rcreate.iounit;
if (qid)
*qid = fcall->params.rcreate.qid;
if (fidp)
*fidp = fid;
kfree(fcall);
return 0;
clunk_fid:
v9fs_t_clunk(v9ses, fid);
fid = V9FS_NOFID;
put_fid:
if (fid >= 0)
v9fs_put_idpool(fid, &v9ses->fidpool);
kfree(fcall);
return err;
}
static struct v9fs_fid*
v9fs_clone_walk(struct v9fs_session_info *v9ses, u32 fid, struct dentry *dentry)
{
int err;
u32 nfid;
struct v9fs_fid *ret;
struct v9fs_fcall *fcall;
nfid = v9fs_get_idpool(&v9ses->fidpool);
if (nfid < 0) {
eprintk(KERN_WARNING, "no free fids available\n");
return ERR_PTR(-ENOSPC);
}
err = v9fs_t_walk(v9ses, fid, nfid, (char *) dentry->d_name.name,
&fcall);
if (err < 0) {
if (fcall && fcall->id == RWALK)
goto clunk_fid;
PRINT_FCALL_ERROR("walk error", fcall);
v9fs_put_idpool(nfid, &v9ses->fidpool);
goto error;
}
kfree(fcall);
fcall = NULL;
ret = v9fs_fid_create(v9ses, nfid);
if (!ret) {
err = -ENOMEM;
goto clunk_fid;
}
err = v9fs_fid_insert(ret, dentry);
if (err < 0) {
v9fs_fid_destroy(ret);
goto clunk_fid;
}
return ret;
clunk_fid:
v9fs_t_clunk(v9ses, nfid);
error:
kfree(fcall);
return ERR_PTR(err);
}
static struct inode *
v9fs_inode_from_fid(struct v9fs_session_info *v9ses, u32 fid,
struct super_block *sb)
{
int err, umode;
struct inode *ret;
struct v9fs_fcall *fcall;
ret = NULL;
err = v9fs_t_stat(v9ses, fid, &fcall);
if (err) {
PRINT_FCALL_ERROR("stat error", fcall);
goto error;
}
umode = p9mode2unixmode(v9ses, fcall->params.rstat.stat.mode);
ret = v9fs_get_inode(sb, umode);
if (IS_ERR(ret)) {
err = PTR_ERR(ret);
ret = NULL;
goto error;
}
v9fs_stat2inode(&fcall->params.rstat.stat, ret, sb);
kfree(fcall);
return ret;
error:
kfree(fcall);
if (ret)
iput(ret);
return ERR_PTR(err);
}
/**
* v9fs_remove - helper function to remove files and directories
* @dir: directory inode that is being deleted
* @file: dentry that is being deleted
* @rmdir: removing a directory
*
*/
static int v9fs_remove(struct inode *dir, struct dentry *file, int rmdir)
{
struct v9fs_fcall *fcall = NULL;
struct super_block *sb = NULL;
struct v9fs_session_info *v9ses = NULL;
struct v9fs_fid *v9fid = NULL;
struct inode *file_inode = NULL;
int fid = -1;
int result = 0;
dprintk(DEBUG_VFS, "inode: %p dentry: %p rmdir: %d\n", dir, file,
rmdir);
file_inode = file->d_inode;
sb = file_inode->i_sb;
v9ses = v9fs_inode2v9ses(file_inode);
v9fid = v9fs_fid_lookup(file);
if (!v9fid) {
dprintk(DEBUG_ERROR,
"no v9fs_fid\n");
return -EBADF;
}
fid = v9fid->fid;
if (fid < 0) {
dprintk(DEBUG_ERROR, "inode #%lu, no fid!\n",
file_inode->i_ino);
return -EBADF;
}
result = v9fs_t_remove(v9ses, fid, &fcall);
if (result < 0) {
PRINT_FCALL_ERROR("remove fails", fcall);
} else {
v9fs_put_idpool(fid, &v9ses->fidpool);
v9fs_fid_destroy(v9fid);
}
kfree(fcall);
return result;
}
static int
v9fs_open_created(struct inode *inode, struct file *file)
{
return 0;
}
/**
* v9fs_vfs_create - VFS hook to create files
* @inode: directory inode that is being deleted
* @dentry: dentry that is being deleted
* @mode: create permissions
* @nd: path information
*
*/
static int
v9fs_vfs_create(struct inode *dir, struct dentry *dentry, int mode,
struct nameidata *nd)
{
int err;
u32 fid, perm, iounit;
int flags;
struct v9fs_session_info *v9ses;
struct v9fs_fid *dfid, *vfid, *ffid;
struct inode *inode;
struct v9fs_qid qid;
struct file *filp;
inode = NULL;
vfid = NULL;
v9ses = v9fs_inode2v9ses(dir);
dfid = v9fs_fid_lookup(dentry->d_parent);
perm = unixmode2p9mode(v9ses, mode);
if (nd && nd->flags & LOOKUP_OPEN)
flags = nd->intent.open.flags - 1;
else
flags = O_RDWR;
err = v9fs_create(v9ses, dfid->fid, (char *) dentry->d_name.name,
perm, v9fs_uflags2omode(flags), NULL, &fid, &qid, &iounit);
if (err)
goto error;
vfid = v9fs_clone_walk(v9ses, dfid->fid, dentry);
if (IS_ERR(vfid)) {
err = PTR_ERR(vfid);
vfid = NULL;
goto error;
}
inode = v9fs_inode_from_fid(v9ses, vfid->fid, dir->i_sb);
if (IS_ERR(inode)) {
err = PTR_ERR(inode);
inode = NULL;
goto error;
}
dentry->d_op = &v9fs_dentry_operations;
d_instantiate(dentry, inode);
if (nd && nd->flags & LOOKUP_OPEN) {
ffid = v9fs_fid_create(v9ses, fid);
if (!ffid)
return -ENOMEM;
filp = lookup_instantiate_filp(nd, dentry, v9fs_open_created);
if (IS_ERR(filp)) {
v9fs_fid_destroy(ffid);
return PTR_ERR(filp);
}
ffid->rdir_pos = 0;
ffid->rdir_fcall = NULL;
ffid->fidopen = 1;
ffid->iounit = iounit;
ffid->filp = filp;
filp->private_data = ffid;
}
return 0;
error:
if (vfid)
v9fs_fid_destroy(vfid);
if (inode)
iput(inode);
return err;
}
/**
* v9fs_vfs_mkdir - VFS mkdir hook to create a directory
* @inode: inode that is being unlinked
* @dentry: dentry that is being unlinked
* @mode: mode for new directory
*
*/
static int v9fs_vfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
{
int err;
u32 fid, perm;
struct v9fs_session_info *v9ses;
struct v9fs_fid *dfid, *vfid;
struct inode *inode;
inode = NULL;
vfid = NULL;
v9ses = v9fs_inode2v9ses(dir);
dfid = v9fs_fid_lookup(dentry->d_parent);
perm = unixmode2p9mode(v9ses, mode | S_IFDIR);
err = v9fs_create(v9ses, dfid->fid, (char *) dentry->d_name.name,
perm, V9FS_OREAD, NULL, &fid, NULL, NULL);
if (err) {
dprintk(DEBUG_ERROR, "create error %d\n", err);
goto error;
}
err = v9fs_t_clunk(v9ses, fid);
if (err) {
dprintk(DEBUG_ERROR, "clunk error %d\n", err);
goto error;
}
vfid = v9fs_clone_walk(v9ses, dfid->fid, dentry);
if (IS_ERR(vfid)) {
err = PTR_ERR(vfid);
vfid = NULL;
goto error;
}
inode = v9fs_inode_from_fid(v9ses, vfid->fid, dir->i_sb);
if (IS_ERR(inode)) {
err = PTR_ERR(inode);
inode = NULL;
goto error;
}
dentry->d_op = &v9fs_dentry_operations;
d_instantiate(dentry, inode);
return 0;
error:
if (vfid)
v9fs_fid_destroy(vfid);
return err;
}
/**
* v9fs_vfs_lookup - VFS lookup hook to "walk" to a new inode
* @dir: inode that is being walked from
* @dentry: dentry that is being walked to?
* @nameidata: path data
*
*/
static struct dentry *v9fs_vfs_lookup(struct inode *dir, struct dentry *dentry,
struct nameidata *nameidata)
{
struct super_block *sb;
struct v9fs_session_info *v9ses;
struct v9fs_fid *dirfid;
struct v9fs_fid *fid;
struct inode *inode;
struct v9fs_fcall *fcall = NULL;
int dirfidnum = -1;
int newfid = -1;
int result = 0;
dprintk(DEBUG_VFS, "dir: %p dentry: (%s) %p nameidata: %p\n",
dir, dentry->d_name.name, dentry, nameidata);
sb = dir->i_sb;
v9ses = v9fs_inode2v9ses(dir);
dentry->d_op = &v9fs_dentry_operations;
dirfid = v9fs_fid_lookup(dentry->d_parent);
if (!dirfid) {
dprintk(DEBUG_ERROR, "no dirfid\n");
return ERR_PTR(-EINVAL);
}
dirfidnum = dirfid->fid;
if (dirfidnum < 0) {
dprintk(DEBUG_ERROR, "no dirfid for inode %p, #%lu\n",
dir, dir->i_ino);
return ERR_PTR(-EBADF);
}
newfid = v9fs_get_idpool(&v9ses->fidpool);
if (newfid < 0) {
eprintk(KERN_WARNING, "newfid fails!\n");
return ERR_PTR(-ENOSPC);
}
result = v9fs_t_walk(v9ses, dirfidnum, newfid,
(char *)dentry->d_name.name, &fcall);
if (result < 0) {
if (fcall && fcall->id == RWALK)
v9fs_t_clunk(v9ses, newfid);
else
v9fs_put_idpool(newfid, &v9ses->fidpool);
if (result == -ENOENT) {
d_add(dentry, NULL);
dprintk(DEBUG_VFS,
"Return negative dentry %p count %d\n",
dentry, atomic_read(&dentry->d_count));
kfree(fcall);
return NULL;
}
dprintk(DEBUG_ERROR, "walk error:%d\n", result);
goto FreeFcall;
}
kfree(fcall);
result = v9fs_t_stat(v9ses, newfid, &fcall);
if (result < 0) {
dprintk(DEBUG_ERROR, "stat error\n");
goto FreeFcall;
}
inode = v9fs_get_inode(sb, p9mode2unixmode(v9ses,
fcall->params.rstat.stat.mode));
if (IS_ERR(inode) && (PTR_ERR(inode) == -ENOSPC)) {
eprintk(KERN_WARNING, "inode alloc failes, returns %ld\n",
PTR_ERR(inode));
result = -ENOSPC;
goto FreeFcall;
}
inode->i_ino = v9fs_qid2ino(&fcall->params.rstat.stat.qid);
fid = v9fs_fid_create(v9ses, newfid);
if (fid == NULL) {
dprintk(DEBUG_ERROR, "couldn't insert\n");
result = -ENOMEM;
goto FreeFcall;
}
result = v9fs_fid_insert(fid, dentry);
if (result < 0)
goto FreeFcall;
fid->qid = fcall->params.rstat.stat.qid;
v9fs_stat2inode(&fcall->params.rstat.stat, inode, inode->i_sb);
d_add(dentry, inode);
kfree(fcall);
return NULL;
FreeFcall:
kfree(fcall);
return ERR_PTR(result);
}
/**
* v9fs_vfs_unlink - VFS unlink hook to delete an inode
* @i: inode that is being unlinked
* @d: dentry that is being unlinked
*
*/
static int v9fs_vfs_unlink(struct inode *i, struct dentry *d)
{
return v9fs_remove(i, d, 0);
}
/**
* v9fs_vfs_rmdir - VFS unlink hook to delete a directory
* @i: inode that is being unlinked
* @d: dentry that is being unlinked
*
*/
static int v9fs_vfs_rmdir(struct inode *i, struct dentry *d)
{
return v9fs_remove(i, d, 1);
}
/**
* v9fs_vfs_rename - VFS hook to rename an inode
* @old_dir: old dir inode
* @old_dentry: old dentry
* @new_dir: new dir inode
* @new_dentry: new dentry
*
*/
static int
v9fs_vfs_rename(struct inode *old_dir, struct dentry *old_dentry,
struct inode *new_dir, struct dentry *new_dentry)
{
struct inode *old_inode = old_dentry->d_inode;
struct v9fs_session_info *v9ses = v9fs_inode2v9ses(old_inode);
struct v9fs_fid *oldfid = v9fs_fid_lookup(old_dentry);
struct v9fs_fid *olddirfid =
v9fs_fid_lookup(old_dentry->d_parent);
struct v9fs_fid *newdirfid =
v9fs_fid_lookup(new_dentry->d_parent);
struct v9fs_wstat wstat;
struct v9fs_fcall *fcall = NULL;
int fid = -1;
int olddirfidnum = -1;
int newdirfidnum = -1;
int retval = 0;
dprintk(DEBUG_VFS, "\n");
if ((!oldfid) || (!olddirfid) || (!newdirfid)) {
dprintk(DEBUG_ERROR, "problem with arguments\n");
return -EBADF;
}
/* 9P can only handle file rename in the same directory */
if (memcmp(&olddirfid->qid, &newdirfid->qid, sizeof(newdirfid->qid))) {
dprintk(DEBUG_ERROR, "old dir and new dir are different\n");
retval = -EPERM;
goto FreeFcallnBail;
}
fid = oldfid->fid;
olddirfidnum = olddirfid->fid;
newdirfidnum = newdirfid->fid;
if (fid < 0) {
dprintk(DEBUG_ERROR, "no fid for old file #%lu\n",
old_inode->i_ino);
retval = -EBADF;
goto FreeFcallnBail;
}
v9fs_blank_wstat(&wstat);
wstat.muid = v9ses->name;
wstat.name = (char *) new_dentry->d_name.name;
retval = v9fs_t_wstat(v9ses, fid, &wstat, &fcall);
FreeFcallnBail:
if (retval < 0)
PRINT_FCALL_ERROR("wstat error", fcall);
kfree(fcall);
return retval;
}
/**
* v9fs_vfs_getattr - retrieve file metadata
* @mnt - mount information
* @dentry - file to get attributes on
* @stat - metadata structure to populate
*
*/
static int
v9fs_vfs_getattr(struct vfsmount *mnt, struct dentry *dentry,
struct kstat *stat)
{
struct v9fs_fcall *fcall = NULL;
struct v9fs_session_info *v9ses = v9fs_inode2v9ses(dentry->d_inode);
struct v9fs_fid *fid = v9fs_fid_lookup(dentry);
int err = -EPERM;
dprintk(DEBUG_VFS, "dentry: %p\n", dentry);
if (!fid) {
dprintk(DEBUG_ERROR,
"couldn't find fid associated with dentry\n");
return -EBADF;
}
err = v9fs_t_stat(v9ses, fid->fid, &fcall);
if (err < 0)
dprintk(DEBUG_ERROR, "stat error\n");
else {
v9fs_stat2inode(&fcall->params.rstat.stat, dentry->d_inode,
dentry->d_inode->i_sb);
generic_fillattr(dentry->d_inode, stat);
}
kfree(fcall);
return err;
}
/**
* v9fs_vfs_setattr - set file metadata
* @dentry: file whose metadata to set
* @iattr: metadata assignment structure
*
*/
static int v9fs_vfs_setattr(struct dentry *dentry, struct iattr *iattr)
{
struct v9fs_session_info *v9ses = v9fs_inode2v9ses(dentry->d_inode);
struct v9fs_fid *fid = v9fs_fid_lookup(dentry);
struct v9fs_fcall *fcall = NULL;
struct v9fs_wstat wstat;
int res = -EPERM;
dprintk(DEBUG_VFS, "\n");
if (!fid) {
dprintk(DEBUG_ERROR,
"Couldn't find fid associated with dentry\n");
return -EBADF;
}
v9fs_blank_wstat(&wstat);
if (iattr->ia_valid & ATTR_MODE)
wstat.mode = unixmode2p9mode(v9ses, iattr->ia_mode);
if (iattr->ia_valid & ATTR_MTIME)
wstat.mtime = iattr->ia_mtime.tv_sec;
if (iattr->ia_valid & ATTR_ATIME)
wstat.atime = iattr->ia_atime.tv_sec;
if (iattr->ia_valid & ATTR_SIZE)
wstat.length = iattr->ia_size;
if (v9ses->extended) {
if (iattr->ia_valid & ATTR_UID)
wstat.n_uid = iattr->ia_uid;
if (iattr->ia_valid & ATTR_GID)
wstat.n_gid = iattr->ia_gid;
}
res = v9fs_t_wstat(v9ses, fid->fid, &wstat, &fcall);
if (res < 0)
PRINT_FCALL_ERROR("wstat error", fcall);
kfree(fcall);
if (res >= 0)
res = inode_setattr(dentry->d_inode, iattr);
return res;
}
/**
* v9fs_stat2inode - populate an inode structure with mistat info
* @stat: Plan 9 metadata (mistat) structure
* @inode: inode to populate
* @sb: superblock of filesystem
*
*/
void
v9fs_stat2inode(struct v9fs_stat *stat, struct inode *inode,
struct super_block *sb)
{
int n;
char ext[32];
struct v9fs_session_info *v9ses = sb->s_fs_info;
inode->i_nlink = 1;
inode->i_atime.tv_sec = stat->atime;
inode->i_mtime.tv_sec = stat->mtime;
inode->i_ctime.tv_sec = stat->mtime;
inode->i_uid = v9ses->uid;
inode->i_gid = v9ses->gid;
if (v9ses->extended) {
inode->i_uid = stat->n_uid;
inode->i_gid = stat->n_gid;
}
inode->i_mode = p9mode2unixmode(v9ses, stat->mode);
if ((S_ISBLK(inode->i_mode)) || (S_ISCHR(inode->i_mode))) {
char type = 0;
int major = -1;
int minor = -1;
n = stat->extension.len;
if (n > sizeof(ext)-1)
n = sizeof(ext)-1;
memmove(ext, stat->extension.str, n);
ext[n] = 0;
sscanf(ext, "%c %u %u", &type, &major, &minor);
switch (type) {
case 'c':
inode->i_mode &= ~S_IFBLK;
inode->i_mode |= S_IFCHR;
break;
case 'b':
break;
default:
dprintk(DEBUG_ERROR, "Unknown special type %c (%.*s)\n",
type, stat->extension.len, stat->extension.str);
};
inode->i_rdev = MKDEV(major, minor);
} else
inode->i_rdev = 0;
inode->i_size = stat->length;
inode->i_blksize = sb->s_blocksize;
inode->i_blocks =
(inode->i_size + inode->i_blksize - 1) >> sb->s_blocksize_bits;
}
/**
* v9fs_qid2ino - convert qid into inode number
* @qid: qid to hash
*
* BUG: potential for inode number collisions?
*/
ino_t v9fs_qid2ino(struct v9fs_qid *qid)
{
u64 path = qid->path + 2;
ino_t i = 0;
if (sizeof(ino_t) == sizeof(path))
memcpy(&i, &path, sizeof(ino_t));
else
i = (ino_t) (path ^ (path >> 32));
return i;
}
/**
* v9fs_readlink - read a symlink's location (internal version)
* @dentry: dentry for symlink
* @buffer: buffer to load symlink location into
* @buflen: length of buffer
*
*/
static int v9fs_readlink(struct dentry *dentry, char *buffer, int buflen)
{
int retval = -EPERM;
struct v9fs_fcall *fcall = NULL;
struct v9fs_session_info *v9ses = v9fs_inode2v9ses(dentry->d_inode);
struct v9fs_fid *fid = v9fs_fid_lookup(dentry);
if (!fid) {
dprintk(DEBUG_ERROR, "could not resolve fid from dentry\n");
retval = -EBADF;
goto FreeFcall;
}
if (!v9ses->extended) {
retval = -EBADF;
dprintk(DEBUG_ERROR, "not extended\n");
goto FreeFcall;
}
dprintk(DEBUG_VFS, " %s\n", dentry->d_name.name);
retval = v9fs_t_stat(v9ses, fid->fid, &fcall);
if (retval < 0) {
dprintk(DEBUG_ERROR, "stat error\n");
goto FreeFcall;
}
if (!fcall)
return -EIO;
if (!(fcall->params.rstat.stat.mode & V9FS_DMSYMLINK)) {
retval = -EINVAL;
goto FreeFcall;
}
/* copy extension buffer into buffer */
if (fcall->params.rstat.stat.extension.len < buflen)
buflen = fcall->params.rstat.stat.extension.len + 1;
memmove(buffer, fcall->params.rstat.stat.extension.str, buflen - 1);
buffer[buflen-1] = 0;
dprintk(DEBUG_ERROR, "%s -> %.*s (%s)\n", dentry->d_name.name, fcall->params.rstat.stat.extension.len,
fcall->params.rstat.stat.extension.str, buffer);
retval = buflen;
FreeFcall:
kfree(fcall);
return retval;
}
/**
* v9fs_vfs_readlink - read a symlink's location
* @dentry: dentry for symlink
* @buf: buffer to load symlink location into
* @buflen: length of buffer
*
*/
static int v9fs_vfs_readlink(struct dentry *dentry, char __user * buffer,
int buflen)
{
int retval;
int ret;
char *link = __getname();
if (buflen > PATH_MAX)
buflen = PATH_MAX;
dprintk(DEBUG_VFS, " dentry: %s (%p)\n", dentry->d_iname, dentry);
retval = v9fs_readlink(dentry, link, buflen);
if (retval > 0) {
if ((ret = copy_to_user(buffer, link, retval)) != 0) {
dprintk(DEBUG_ERROR, "problem copying to user: %d\n",
ret);
retval = ret;
}
}
__putname(link);
return retval;
}
/**
* v9fs_vfs_follow_link - follow a symlink path
* @dentry: dentry for symlink
* @nd: nameidata
*
*/
static void *v9fs_vfs_follow_link(struct dentry *dentry, struct nameidata *nd)
{
int len = 0;
char *link = __getname();
dprintk(DEBUG_VFS, "%s n", dentry->d_name.name);
if (!link)
link = ERR_PTR(-ENOMEM);
else {
len = v9fs_readlink(dentry, link, PATH_MAX);
if (len < 0) {
__putname(link);
link = ERR_PTR(len);
} else
link[len] = 0;
}
nd_set_link(nd, link);
return NULL;
}
/**
* v9fs_vfs_put_link - release a symlink path
* @dentry: dentry for symlink
* @nd: nameidata
*
*/
static void v9fs_vfs_put_link(struct dentry *dentry, struct nameidata *nd, void *p)
{
char *s = nd_get_link(nd);
dprintk(DEBUG_VFS, " %s %s\n", dentry->d_name.name, s);
if (!IS_ERR(s))
__putname(s);
}
static int v9fs_vfs_mkspecial(struct inode *dir, struct dentry *dentry,
int mode, const char *extension)
{
int err;
u32 fid, perm;
struct v9fs_session_info *v9ses;
struct v9fs_fid *dfid, *vfid;
struct inode *inode;
inode = NULL;
vfid = NULL;
v9ses = v9fs_inode2v9ses(dir);
dfid = v9fs_fid_lookup(dentry->d_parent);
perm = unixmode2p9mode(v9ses, mode);
if (!v9ses->extended) {
dprintk(DEBUG_ERROR, "not extended\n");
return -EPERM;
}
err = v9fs_create(v9ses, dfid->fid, (char *) dentry->d_name.name,
perm, V9FS_OREAD, (char *) extension, &fid, NULL, NULL);
if (err)
goto error;
err = v9fs_t_clunk(v9ses, fid);
if (err)
goto error;
vfid = v9fs_clone_walk(v9ses, dfid->fid, dentry);
if (IS_ERR(vfid)) {
err = PTR_ERR(vfid);
vfid = NULL;
goto error;
}
inode = v9fs_inode_from_fid(v9ses, vfid->fid, dir->i_sb);
if (IS_ERR(inode)) {
err = PTR_ERR(inode);
inode = NULL;
goto error;
}
dentry->d_op = &v9fs_dentry_operations;
d_instantiate(dentry, inode);
return 0;
error:
if (vfid)
v9fs_fid_destroy(vfid);
if (inode)
iput(inode);
return err;
}
/**
* v9fs_vfs_symlink - helper function to create symlinks
* @dir: directory inode containing symlink
* @dentry: dentry for symlink
* @symname: symlink data
*
* See 9P2000.u RFC for more information
*
*/
static int
v9fs_vfs_symlink(struct inode *dir, struct dentry *dentry, const char *symname)
{
dprintk(DEBUG_VFS, " %lu,%s,%s\n", dir->i_ino, dentry->d_name.name,
symname);
return v9fs_vfs_mkspecial(dir, dentry, S_IFLNK, symname);
}
/**
* v9fs_vfs_link - create a hardlink
* @old_dentry: dentry for file to link to
* @dir: inode destination for new link
* @dentry: dentry for link
*
*/
/* XXX - lots of code dup'd from symlink and creates,
* figure out a better reuse strategy
*/
static int
v9fs_vfs_link(struct dentry *old_dentry, struct inode *dir,
struct dentry *dentry)
{
int retval;
struct v9fs_fid *oldfid;
char *name;
dprintk(DEBUG_VFS, " %lu,%s,%s\n", dir->i_ino, dentry->d_name.name,
old_dentry->d_name.name);
oldfid = v9fs_fid_lookup(old_dentry);
if (!oldfid) {
dprintk(DEBUG_ERROR, "can't find oldfid\n");
return -EPERM;
}
name = __getname();
sprintf(name, "%d\n", oldfid->fid);
retval = v9fs_vfs_mkspecial(dir, dentry, V9FS_DMLINK, name);
__putname(name);
return retval;
}
/**
* v9fs_vfs_mknod - create a special file
* @dir: inode destination for new link
* @dentry: dentry for file
* @mode: mode for creation
* @dev_t: device associated with special file
*
*/
static int
v9fs_vfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t rdev)
{
int retval;
char *name;
dprintk(DEBUG_VFS, " %lu,%s mode: %x MAJOR: %u MINOR: %u\n", dir->i_ino,
dentry->d_name.name, mode, MAJOR(rdev), MINOR(rdev));
if (!new_valid_dev(rdev))
return -EINVAL;
name = __getname();
if (!name)
return -ENOMEM;
/* build extension */
if (S_ISBLK(mode))
sprintf(name, "b %u %u", MAJOR(rdev), MINOR(rdev));
else if (S_ISCHR(mode))
sprintf(name, "c %u %u", MAJOR(rdev), MINOR(rdev));
else if (S_ISFIFO(mode))
*name = 0;
else {
__putname(name);
return -EINVAL;
}
retval = v9fs_vfs_mkspecial(dir, dentry, mode, name);
__putname(name);
return retval;
}
static struct inode_operations v9fs_dir_inode_operations_ext = {
.create = v9fs_vfs_create,
.lookup = v9fs_vfs_lookup,
.symlink = v9fs_vfs_symlink,
.link = v9fs_vfs_link,
.unlink = v9fs_vfs_unlink,
.mkdir = v9fs_vfs_mkdir,
.rmdir = v9fs_vfs_rmdir,
.mknod = v9fs_vfs_mknod,
.rename = v9fs_vfs_rename,
.readlink = v9fs_vfs_readlink,
.getattr = v9fs_vfs_getattr,
.setattr = v9fs_vfs_setattr,
};
static struct inode_operations v9fs_dir_inode_operations = {
.create = v9fs_vfs_create,
.lookup = v9fs_vfs_lookup,
.unlink = v9fs_vfs_unlink,
.mkdir = v9fs_vfs_mkdir,
.rmdir = v9fs_vfs_rmdir,
.mknod = v9fs_vfs_mknod,
.rename = v9fs_vfs_rename,
.getattr = v9fs_vfs_getattr,
.setattr = v9fs_vfs_setattr,
};
static struct inode_operations v9fs_file_inode_operations = {
.getattr = v9fs_vfs_getattr,
.setattr = v9fs_vfs_setattr,
};
static struct inode_operations v9fs_symlink_inode_operations = {
.readlink = v9fs_vfs_readlink,
.follow_link = v9fs_vfs_follow_link,
.put_link = v9fs_vfs_put_link,
.getattr = v9fs_vfs_getattr,
.setattr = v9fs_vfs_setattr,
};