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f085312204
linux/fs/9p/vfs_inode.c
Sripathi Kodi f085312204 9p: getattr client implementation for 9P2000.L protocol. 
SYNOPSIS

              size[4] Tgetattr tag[2] fid[4] request_mask[8]

              size[4] Rgetattr tag[2] lstat[n]

           DESCRIPTION

              The getattr transaction inquires about the file identified by fid.
              request_mask is a bit mask that specifies which fields of the
              stat structure is the client interested in.

              The reply will contain a machine-independent directory entry,
              laid out as follows:

                 st_result_mask[8]
                    Bit mask that indicates which fields in the stat structure
                    have been populated by the server

                 qid.type[1]
                    the type of the file (directory, etc.), represented as a bit
                    vector corresponding to the high 8 bits of the file's mode
                    word.

                 qid.vers[4]
                    version number for given path

                 qid.path[8]
                    the file server's unique identification for the file

                 st_mode[4]
                    Permission and flags

                 st_uid[4]
                    User id of owner

                 st_gid[4]
                    Group ID of owner

                 st_nlink[8]
                    Number of hard links

                 st_rdev[8]
                    Device ID (if special file)

                 st_size[8]
                    Size, in bytes

                 st_blksize[8]
                    Block size for file system IO

                 st_blocks[8]
                    Number of file system blocks allocated

                 st_atime_sec[8]
                    Time of last access, seconds

                 st_atime_nsec[8]
                    Time of last access, nanoseconds

                 st_mtime_sec[8]
                    Time of last modification, seconds

                 st_mtime_nsec[8]
                    Time of last modification, nanoseconds

                 st_ctime_sec[8]
                    Time of last status change, seconds

                 st_ctime_nsec[8]
                    Time of last status change, nanoseconds

                 st_btime_sec[8]
                    Time of creation (birth) of file, seconds

                 st_btime_nsec[8]
                    Time of creation (birth) of file, nanoseconds

                 st_gen[8]
                    Inode generation

                 st_data_version[8]
                    Data version number

              request_mask and result_mask bit masks contain the following bits
                 #define P9_STATS_MODE          0x00000001ULL
                 #define P9_STATS_NLINK         0x00000002ULL
                 #define P9_STATS_UID           0x00000004ULL
                 #define P9_STATS_GID           0x00000008ULL
                 #define P9_STATS_RDEV          0x00000010ULL
                 #define P9_STATS_ATIME         0x00000020ULL
                 #define P9_STATS_MTIME         0x00000040ULL
                 #define P9_STATS_CTIME         0x00000080ULL
                 #define P9_STATS_INO           0x00000100ULL
                 #define P9_STATS_SIZE          0x00000200ULL
                 #define P9_STATS_BLOCKS        0x00000400ULL

                 #define P9_STATS_BTIME         0x00000800ULL
                 #define P9_STATS_GEN           0x00001000ULL
                 #define P9_STATS_DATA_VERSION  0x00002000ULL

                 #define P9_STATS_BASIC         0x000007ffULL
                 #define P9_STATS_ALL           0x00003fffULL

        This patch implements the client side of getattr implementation for
        9P2000.L. It introduces a new structure p9_stat_dotl for getting
        Linux stat information along with QID. The data layout is similar to
        stat structure in Linux user space with the following major
        differences:

        inode (st_ino) is not part of data. Instead qid is.

        device (st_dev) is not part of data because this doesn't make sense
        on the client.

        All time variables are 64 bit wide on the wire. The kernel seems to use
        32 bit variables for these variables. However, some of the architectures
        have used 64 bit variables and glibc exposes 64 bit variables to user
        space on some architectures. Hence to be on the safer side we have made
        these 64 bit in the protocol. Refer to the comments in
        include/asm-generic/stat.h

        There are some additional fields: st_btime_sec, st_btime_nsec, st_gen,
        st_data_version apart from the bitmask, st_result_mask. The bit mask
        is filled by the server to indicate which stat fields have been
        populated by the server. Currently there is no clean way for the
        server to obtain these additional fields, so it sends back just the
        basic fields.

Signed-off-by: Sripathi Kodi <sripathik@in.ibm.com>
Signed-off-by: Eric Van Hensbegren <ericvh@gmail.com>
2010-08-02 14:25:09 -05:00

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/*
* 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/inet.h>
#include <linux/namei.h>
#include <linux/idr.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <net/9p/9p.h>
#include <net/9p/client.h>
#include "v9fs.h"
#include "v9fs_vfs.h"
#include "fid.h"
#include "cache.h"
static const struct inode_operations v9fs_dir_inode_operations;
static const struct inode_operations v9fs_dir_inode_operations_dotu;
static const struct inode_operations v9fs_dir_inode_operations_dotl;
static const struct inode_operations v9fs_file_inode_operations;
static const struct inode_operations v9fs_file_inode_operations_dotl;
static const struct inode_operations v9fs_symlink_inode_operations;
static const struct inode_operations v9fs_symlink_inode_operations_dotl;
/**
* 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 |= P9_DMDIR;
if (v9fs_proto_dotu(v9ses)) {
if (S_ISLNK(mode))
res |= P9_DMSYMLINK;
if (v9ses->nodev == 0) {
if (S_ISSOCK(mode))
res |= P9_DMSOCKET;
if (S_ISFIFO(mode))
res |= P9_DMNAMEDPIPE;
if (S_ISBLK(mode))
res |= P9_DMDEVICE;
if (S_ISCHR(mode))
res |= P9_DMDEVICE;
}
if ((mode & S_ISUID) == S_ISUID)
res |= P9_DMSETUID;
if ((mode & S_ISGID) == S_ISGID)
res |= P9_DMSETGID;
if ((mode & S_ISVTX) == S_ISVTX)
res |= P9_DMSETVTX;
if ((mode & P9_DMLINK))
res |= P9_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 & P9_DMDIR) == P9_DMDIR)
res |= S_IFDIR;
else if ((mode & P9_DMSYMLINK) && (v9fs_proto_dotu(v9ses)))
res |= S_IFLNK;
else if ((mode & P9_DMSOCKET) && (v9fs_proto_dotu(v9ses))
&& (v9ses->nodev == 0))
res |= S_IFSOCK;
else if ((mode & P9_DMNAMEDPIPE) && (v9fs_proto_dotu(v9ses))
&& (v9ses->nodev == 0))
res |= S_IFIFO;
else if ((mode & P9_DMDEVICE) && (v9fs_proto_dotu(v9ses))
&& (v9ses->nodev == 0))
res |= S_IFBLK;
else
res |= S_IFREG;
if (v9fs_proto_dotu(v9ses)) {
if ((mode & P9_DMSETUID) == P9_DMSETUID)
res |= S_ISUID;
if ((mode & P9_DMSETGID) == P9_DMSETGID)
res |= S_ISGID;
if ((mode & P9_DMSETVTX) == P9_DMSETVTX)
res |= S_ISVTX;
}
return res;
}
/**
* v9fs_uflags2omode- convert posix open flags to plan 9 mode bits
* @uflags: flags to convert
* @extended: if .u extensions are active
*/
int v9fs_uflags2omode(int uflags, int extended)
{
int ret;
ret = 0;
switch (uflags&3) {
default:
case O_RDONLY:
ret = P9_OREAD;
break;
case O_WRONLY:
ret = P9_OWRITE;
break;
case O_RDWR:
ret = P9_ORDWR;
break;
}
if (uflags & O_TRUNC)
ret |= P9_OTRUNC;
if (extended) {
if (uflags & O_EXCL)
ret |= P9_OEXCL;
if (uflags & O_APPEND)
ret |= P9_OAPPEND;
}
return ret;
}
/**
* v9fs_blank_wstat - helper function to setup a 9P stat structure
* @wstat: structure to initialize
*
*/
void
v9fs_blank_wstat(struct p9_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;
}
#ifdef CONFIG_9P_FSCACHE
/**
* v9fs_alloc_inode - helper function to allocate an inode
* This callback is executed before setting up the inode so that we
* can associate a vcookie with each inode.
*
*/
struct inode *v9fs_alloc_inode(struct super_block *sb)
{
struct v9fs_cookie *vcookie;
vcookie = (struct v9fs_cookie *)kmem_cache_alloc(vcookie_cache,
GFP_KERNEL);
if (!vcookie)
return NULL;
vcookie->fscache = NULL;
vcookie->qid = NULL;
spin_lock_init(&vcookie->lock);
return &vcookie->inode;
}
/**
* v9fs_destroy_inode - destroy an inode
*
*/
void v9fs_destroy_inode(struct inode *inode)
{
kmem_cache_free(vcookie_cache, v9fs_inode2cookie(inode));
}
#endif
/**
* 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)
{
int err;
struct inode *inode;
struct v9fs_session_info *v9ses = sb->s_fs_info;
P9_DPRINTK(P9_DEBUG_VFS, "super block: %p mode: %o\n", sb, mode);
inode = new_inode(sb);
if (!inode) {
P9_EPRINTK(KERN_WARNING, "Problem allocating inode\n");
return ERR_PTR(-ENOMEM);
}
inode_init_owner(inode, NULL, mode);
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 (!v9fs_proto_dotu(v9ses)) {
P9_DPRINTK(P9_DEBUG_ERROR,
"special files without extended mode\n");
err = -EINVAL;
goto error;
}
init_special_inode(inode, inode->i_mode, inode->i_rdev);
break;
case S_IFREG:
if (v9fs_proto_dotl(v9ses)) {
inode->i_op = &v9fs_file_inode_operations_dotl;
inode->i_fop = &v9fs_file_operations_dotl;
} else {
inode->i_op = &v9fs_file_inode_operations;
inode->i_fop = &v9fs_file_operations;
}
break;
case S_IFLNK:
if (!v9fs_proto_dotu(v9ses) && !v9fs_proto_dotl(v9ses)) {
P9_DPRINTK(P9_DEBUG_ERROR, "extended modes used with "
"legacy protocol.\n");
err = -EINVAL;
goto error;
}
if (v9fs_proto_dotl(v9ses))
inode->i_op = &v9fs_symlink_inode_operations_dotl;
else
inode->i_op = &v9fs_symlink_inode_operations;
break;
case S_IFDIR:
inc_nlink(inode);
if (v9fs_proto_dotl(v9ses))
inode->i_op = &v9fs_dir_inode_operations_dotl;
else if (v9fs_proto_dotu(v9ses))
inode->i_op = &v9fs_dir_inode_operations_dotu;
else
inode->i_op = &v9fs_dir_inode_operations;
if (v9fs_proto_dotl(v9ses))
inode->i_fop = &v9fs_dir_operations_dotl;
else
inode->i_fop = &v9fs_dir_operations;
break;
default:
P9_DPRINTK(P9_DEBUG_ERROR, "BAD mode 0x%x S_IFMT 0x%x\n",
mode, mode & S_IFMT);
err = -EINVAL;
goto error;
}
return inode;
error:
iput(inode);
return ERR_PTR(err);
}
/*
static struct v9fs_fid*
v9fs_clone_walk(struct v9fs_session_info *v9ses, u32 fid, struct dentry *dentry)
{
int err;
int 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);
}
*/
/**
* v9fs_clear_inode - release an inode
* @inode: inode to release
*
*/
void v9fs_clear_inode(struct inode *inode)
{
filemap_fdatawrite(inode->i_mapping);
#ifdef CONFIG_9P_FSCACHE
v9fs_cache_inode_put_cookie(inode);
#endif
}
static struct inode *
v9fs_inode(struct v9fs_session_info *v9ses, struct p9_fid *fid,
struct super_block *sb)
{
int err, umode;
struct inode *ret = NULL;
struct p9_wstat *st;
st = p9_client_stat(fid);
if (IS_ERR(st))
return ERR_CAST(st);
umode = p9mode2unixmode(v9ses, st->mode);
ret = v9fs_get_inode(sb, umode);
if (IS_ERR(ret)) {
err = PTR_ERR(ret);
goto error;
}
v9fs_stat2inode(st, ret, sb);
ret->i_ino = v9fs_qid2ino(&st->qid);
#ifdef CONFIG_9P_FSCACHE
v9fs_vcookie_set_qid(ret, &st->qid);
v9fs_cache_inode_get_cookie(ret);
#endif
p9stat_free(st);
kfree(st);
return ret;
error:
p9stat_free(st);
kfree(st);
return ERR_PTR(err);
}
static struct inode *
v9fs_inode_dotl(struct v9fs_session_info *v9ses, struct p9_fid *fid,
struct super_block *sb)
{
struct inode *ret = NULL;
int err;
struct p9_stat_dotl *st;
st = p9_client_getattr_dotl(fid, P9_STATS_BASIC);
if (IS_ERR(st))
return ERR_CAST(st);
ret = v9fs_get_inode(sb, st->st_mode);
if (IS_ERR(ret)) {
err = PTR_ERR(ret);
goto error;
}
v9fs_stat2inode_dotl(st, ret);
ret->i_ino = v9fs_qid2ino(&st->qid);
#ifdef CONFIG_9P_FSCACHE
v9fs_vcookie_set_qid(ret, &st->qid);
v9fs_cache_inode_get_cookie(ret);
#endif
kfree(st);
return ret;
error:
kfree(st);
return ERR_PTR(err);
}
/**
* v9fs_inode_from_fid - Helper routine to populate an inode by
* issuing a attribute request
* @v9ses: session information
* @fid: fid to issue attribute request for
* @sb: superblock on which to create inode
*
*/
static inline struct inode *
v9fs_inode_from_fid(struct v9fs_session_info *v9ses, struct p9_fid *fid,
struct super_block *sb)
{
if (v9fs_proto_dotl(v9ses))
return v9fs_inode_dotl(v9ses, fid, sb);
else
return v9fs_inode(v9ses, fid, sb);
}
/**
* 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)
{
int retval;
struct inode *file_inode;
struct p9_fid *v9fid;
P9_DPRINTK(P9_DEBUG_VFS, "inode: %p dentry: %p rmdir: %d\n", dir, file,
rmdir);
file_inode = file->d_inode;
v9fid = v9fs_fid_clone(file);
if (IS_ERR(v9fid))
return PTR_ERR(v9fid);
retval = p9_client_remove(v9fid);
if (!retval)
drop_nlink(file_inode);
return retval;
}
static int
v9fs_open_created(struct inode *inode, struct file *file)
{
return 0;
}
/**
* v9fs_create - Create a file
* @v9ses: session information
* @dir: directory that dentry is being created in
* @dentry: dentry that is being created
* @extension: 9p2000.u extension string to support devices, etc.
* @perm: create permissions
* @mode: open mode
*
*/
static struct p9_fid *
v9fs_create(struct v9fs_session_info *v9ses, struct inode *dir,
struct dentry *dentry, char *extension, u32 perm, u8 mode)
{
int err;
char *name;
struct p9_fid *dfid, *ofid, *fid;
struct inode *inode;
P9_DPRINTK(P9_DEBUG_VFS, "name %s\n", dentry->d_name.name);
err = 0;
ofid = NULL;
fid = NULL;
name = (char *) dentry->d_name.name;
dfid = v9fs_fid_lookup(dentry->d_parent);
if (IS_ERR(dfid)) {
err = PTR_ERR(dfid);
P9_DPRINTK(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
return ERR_PTR(err);
}
/* clone a fid to use for creation */
ofid = p9_client_walk(dfid, 0, NULL, 1);
if (IS_ERR(ofid)) {
err = PTR_ERR(ofid);
P9_DPRINTK(P9_DEBUG_VFS, "p9_client_walk failed %d\n", err);
return ERR_PTR(err);
}
err = p9_client_fcreate(ofid, name, perm, mode, extension);
if (err < 0) {
P9_DPRINTK(P9_DEBUG_VFS, "p9_client_fcreate failed %d\n", err);
goto error;
}
/* now walk from the parent so we can get unopened fid */
fid = p9_client_walk(dfid, 1, &name, 1);
if (IS_ERR(fid)) {
err = PTR_ERR(fid);
P9_DPRINTK(P9_DEBUG_VFS, "p9_client_walk failed %d\n", err);
fid = NULL;
goto error;
}
/* instantiate inode and assign the unopened fid to the dentry */
inode = v9fs_inode_from_fid(v9ses, fid, dir->i_sb);
if (IS_ERR(inode)) {
err = PTR_ERR(inode);
P9_DPRINTK(P9_DEBUG_VFS, "inode creation failed %d\n", err);
goto error;
}
if (v9ses->cache)
dentry->d_op = &v9fs_cached_dentry_operations;
else
dentry->d_op = &v9fs_dentry_operations;
d_instantiate(dentry, inode);
err = v9fs_fid_add(dentry, fid);
if (err < 0)
goto error;
return ofid;
error:
if (ofid)
p9_client_clunk(ofid);
if (fid)
p9_client_clunk(fid);
return ERR_PTR(err);
}
/**
* v9fs_vfs_create - VFS hook to create files
* @dir: directory inode that is being created
* @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 perm;
int flags;
struct v9fs_session_info *v9ses;
struct p9_fid *fid;
struct file *filp;
err = 0;
fid = NULL;
v9ses = v9fs_inode2v9ses(dir);
perm = unixmode2p9mode(v9ses, mode);
if (nd && nd->flags & LOOKUP_OPEN)
flags = nd->intent.open.flags - 1;
else
flags = O_RDWR;
fid = v9fs_create(v9ses, dir, dentry, NULL, perm,
v9fs_uflags2omode(flags,
v9fs_proto_dotu(v9ses)));
if (IS_ERR(fid)) {
err = PTR_ERR(fid);
fid = NULL;
goto error;
}
/* if we are opening a file, assign the open fid to the file */
if (nd && nd->flags & LOOKUP_OPEN) {
filp = lookup_instantiate_filp(nd, dentry, v9fs_open_created);
if (IS_ERR(filp)) {
err = PTR_ERR(filp);
goto error;
}
filp->private_data = fid;
} else
p9_client_clunk(fid);
return 0;
error:
if (fid)
p9_client_clunk(fid);
return err;
}
/**
* v9fs_vfs_mkdir - VFS mkdir hook to create a directory
* @dir: 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 perm;
struct v9fs_session_info *v9ses;
struct p9_fid *fid;
P9_DPRINTK(P9_DEBUG_VFS, "name %s\n", dentry->d_name.name);
err = 0;
v9ses = v9fs_inode2v9ses(dir);
perm = unixmode2p9mode(v9ses, mode | S_IFDIR);
fid = v9fs_create(v9ses, dir, dentry, NULL, perm, P9_OREAD);
if (IS_ERR(fid)) {
err = PTR_ERR(fid);
fid = NULL;
}
if (fid)
p9_client_clunk(fid);
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 p9_fid *dfid, *fid;
struct inode *inode;
char *name;
int result = 0;
P9_DPRINTK(P9_DEBUG_VFS, "dir: %p dentry: (%s) %p nameidata: %p\n",
dir, dentry->d_name.name, dentry, nameidata);
if (dentry->d_name.len > NAME_MAX)
return ERR_PTR(-ENAMETOOLONG);
sb = dir->i_sb;
v9ses = v9fs_inode2v9ses(dir);
dfid = v9fs_fid_lookup(dentry->d_parent);
if (IS_ERR(dfid))
return ERR_CAST(dfid);
name = (char *) dentry->d_name.name;
fid = p9_client_walk(dfid, 1, &name, 1);
if (IS_ERR(fid)) {
result = PTR_ERR(fid);
if (result == -ENOENT) {
inode = NULL;
goto inst_out;
}
return ERR_PTR(result);
}
inode = v9fs_inode_from_fid(v9ses, fid, dir->i_sb);
if (IS_ERR(inode)) {
result = PTR_ERR(inode);
inode = NULL;
goto error;
}
result = v9fs_fid_add(dentry, fid);
if (result < 0)
goto error;
inst_out:
if (v9ses->cache)
dentry->d_op = &v9fs_cached_dentry_operations;
else
dentry->d_op = &v9fs_dentry_operations;
d_add(dentry, inode);
return NULL;
error:
p9_client_clunk(fid);
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;
struct v9fs_session_info *v9ses;
struct p9_fid *oldfid;
struct p9_fid *olddirfid;
struct p9_fid *newdirfid;
struct p9_wstat wstat;
int retval;
P9_DPRINTK(P9_DEBUG_VFS, "\n");
retval = 0;
old_inode = old_dentry->d_inode;
v9ses = v9fs_inode2v9ses(old_inode);
oldfid = v9fs_fid_lookup(old_dentry);
if (IS_ERR(oldfid))
return PTR_ERR(oldfid);
olddirfid = v9fs_fid_clone(old_dentry->d_parent);
if (IS_ERR(olddirfid)) {
retval = PTR_ERR(olddirfid);
goto done;
}
newdirfid = v9fs_fid_clone(new_dentry->d_parent);
if (IS_ERR(newdirfid)) {
retval = PTR_ERR(newdirfid);
goto clunk_olddir;
}
if (v9fs_proto_dotl(v9ses)) {
retval = p9_client_rename(oldfid, newdirfid,
(char *) new_dentry->d_name.name);
if (retval != -ENOSYS)
goto clunk_newdir;
}
/* 9P can only handle file rename in the same directory */
if (memcmp(&olddirfid->qid, &newdirfid->qid, sizeof(newdirfid->qid))) {
P9_DPRINTK(P9_DEBUG_ERROR,
"old dir and new dir are different\n");
retval = -EXDEV;
goto clunk_newdir;
}
v9fs_blank_wstat(&wstat);
wstat.muid = v9ses->uname;
wstat.name = (char *) new_dentry->d_name.name;
retval = p9_client_wstat(oldfid, &wstat);
clunk_newdir:
p9_client_clunk(newdirfid);
clunk_olddir:
p9_client_clunk(olddirfid);
done:
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)
{
int err;
struct v9fs_session_info *v9ses;
struct p9_fid *fid;
struct p9_wstat *st;
P9_DPRINTK(P9_DEBUG_VFS, "dentry: %p\n", dentry);
err = -EPERM;
v9ses = v9fs_inode2v9ses(dentry->d_inode);
if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE)
return simple_getattr(mnt, dentry, stat);
fid = v9fs_fid_lookup(dentry);
if (IS_ERR(fid))
return PTR_ERR(fid);
st = p9_client_stat(fid);
if (IS_ERR(st))
return PTR_ERR(st);
v9fs_stat2inode(st, dentry->d_inode, dentry->d_inode->i_sb);
generic_fillattr(dentry->d_inode, stat);
kfree(st);
return 0;
}
static int
v9fs_vfs_getattr_dotl(struct vfsmount *mnt, struct dentry *dentry,
struct kstat *stat)
{
int err;
struct v9fs_session_info *v9ses;
struct p9_fid *fid;
struct p9_stat_dotl *st;
P9_DPRINTK(P9_DEBUG_VFS, "dentry: %p\n", dentry);
err = -EPERM;
v9ses = v9fs_inode2v9ses(dentry->d_inode);
if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE)
return simple_getattr(mnt, dentry, stat);
fid = v9fs_fid_lookup(dentry);
if (IS_ERR(fid))
return PTR_ERR(fid);
/* Ask for all the fields in stat structure. Server will return
* whatever it supports
*/
st = p9_client_getattr_dotl(fid, P9_STATS_ALL);
if (IS_ERR(st))
return PTR_ERR(st);
v9fs_stat2inode_dotl(st, dentry->d_inode);
generic_fillattr(dentry->d_inode, stat);
/* Change block size to what the server returned */
stat->blksize = st->st_blksize;
kfree(st);
return 0;
}
/**
* 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)
{
int retval;
struct v9fs_session_info *v9ses;
struct p9_fid *fid;
struct p9_wstat wstat;
P9_DPRINTK(P9_DEBUG_VFS, "\n");
retval = -EPERM;
v9ses = v9fs_inode2v9ses(dentry->d_inode);
fid = v9fs_fid_lookup(dentry);
if(IS_ERR(fid))
return PTR_ERR(fid);
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 (v9fs_proto_dotu(v9ses)) {
if (iattr->ia_valid & ATTR_UID)
wstat.n_uid = iattr->ia_uid;
if (iattr->ia_valid & ATTR_GID)
wstat.n_gid = iattr->ia_gid;
}
retval = p9_client_wstat(fid, &wstat);
if (retval >= 0)
retval = inode_setattr(dentry->d_inode, iattr);
return retval;
}
/**
* 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 p9_wstat *stat, struct inode *inode,
struct super_block *sb)
{
char ext[32];
char tag_name[14];
unsigned int i_nlink;
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->dfltuid;
inode->i_gid = v9ses->dfltgid;
if (v9fs_proto_dotu(v9ses)) {
inode->i_uid = stat->n_uid;
inode->i_gid = stat->n_gid;
}
if ((S_ISREG(inode->i_mode)) || (S_ISDIR(inode->i_mode))) {
if (v9fs_proto_dotu(v9ses) && (stat->extension[0] != '\0')) {
/*
* Hadlink support got added later to
* to the .u extension. So there can be
* server out there that doesn't support
* this even with .u extension. So check
* for non NULL stat->extension
*/
strncpy(ext, stat->extension, sizeof(ext));
/* HARDLINKCOUNT %u */
sscanf(ext, "%13s %u", tag_name, &i_nlink);
if (!strncmp(tag_name, "HARDLINKCOUNT", 13))
inode->i_nlink = i_nlink;
}
}
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;
strncpy(ext, stat->extension, sizeof(ext));
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:
P9_DPRINTK(P9_DEBUG_ERROR,
"Unknown special type %c %s\n", type,
stat->extension);
};
inode->i_rdev = MKDEV(major, minor);
init_special_inode(inode, inode->i_mode, inode->i_rdev);
} else
inode->i_rdev = 0;
i_size_write(inode, stat->length);
/* not real number of blocks, but 512 byte ones ... */
inode->i_blocks = (i_size_read(inode) + 512 - 1) >> 9;
}
/**
* v9fs_stat2inode_dotl - populate an inode structure with stat info
* @stat: stat structure
* @inode: inode to populate
* @sb: superblock of filesystem
*
*/
void
v9fs_stat2inode_dotl(struct p9_stat_dotl *stat, struct inode *inode)
{
if ((stat->st_result_mask & P9_STATS_BASIC) == P9_STATS_BASIC) {
inode->i_atime.tv_sec = stat->st_atime_sec;
inode->i_atime.tv_nsec = stat->st_atime_nsec;
inode->i_mtime.tv_sec = stat->st_mtime_sec;
inode->i_mtime.tv_nsec = stat->st_mtime_nsec;
inode->i_ctime.tv_sec = stat->st_ctime_sec;
inode->i_ctime.tv_nsec = stat->st_ctime_nsec;
inode->i_uid = stat->st_uid;
inode->i_gid = stat->st_gid;
inode->i_nlink = stat->st_nlink;
inode->i_mode = stat->st_mode;
inode->i_rdev = new_decode_dev(stat->st_rdev);
if ((S_ISBLK(inode->i_mode)) || (S_ISCHR(inode->i_mode)))
init_special_inode(inode, inode->i_mode, inode->i_rdev);
i_size_write(inode, stat->st_size);
inode->i_blocks = stat->st_blocks;
} else {
if (stat->st_result_mask & P9_STATS_ATIME) {
inode->i_atime.tv_sec = stat->st_atime_sec;
inode->i_atime.tv_nsec = stat->st_atime_nsec;
}
if (stat->st_result_mask & P9_STATS_MTIME) {
inode->i_mtime.tv_sec = stat->st_mtime_sec;
inode->i_mtime.tv_nsec = stat->st_mtime_nsec;
}
if (stat->st_result_mask & P9_STATS_CTIME) {
inode->i_ctime.tv_sec = stat->st_ctime_sec;
inode->i_ctime.tv_nsec = stat->st_ctime_nsec;
}
if (stat->st_result_mask & P9_STATS_UID)
inode->i_uid = stat->st_uid;
if (stat->st_result_mask & P9_STATS_GID)
inode->i_gid = stat->st_gid;
if (stat->st_result_mask & P9_STATS_NLINK)
inode->i_nlink = stat->st_nlink;
if (stat->st_result_mask & P9_STATS_MODE) {
inode->i_mode = stat->st_mode;
if ((S_ISBLK(inode->i_mode)) ||
(S_ISCHR(inode->i_mode)))
init_special_inode(inode, inode->i_mode,
inode->i_rdev);
}
if (stat->st_result_mask & P9_STATS_RDEV)
inode->i_rdev = new_decode_dev(stat->st_rdev);
if (stat->st_result_mask & P9_STATS_SIZE)
i_size_write(inode, stat->st_size);
if (stat->st_result_mask & P9_STATS_BLOCKS)
inode->i_blocks = stat->st_blocks;
}
if (stat->st_result_mask & P9_STATS_GEN)
inode->i_generation = stat->st_gen;
/* Currently we don't support P9_STATS_BTIME and P9_STATS_DATA_VERSION
* because the inode structure does not have fields for them.
*/
}
/**
* v9fs_qid2ino - convert qid into inode number
* @qid: qid to hash
*
* BUG: potential for inode number collisions?
*/
ino_t v9fs_qid2ino(struct p9_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;
struct v9fs_session_info *v9ses;
struct p9_fid *fid;
struct p9_wstat *st;
P9_DPRINTK(P9_DEBUG_VFS, " %s\n", dentry->d_name.name);
retval = -EPERM;
v9ses = v9fs_inode2v9ses(dentry->d_inode);
fid = v9fs_fid_lookup(dentry);
if (IS_ERR(fid))
return PTR_ERR(fid);
if (!v9fs_proto_dotu(v9ses))
return -EBADF;
st = p9_client_stat(fid);
if (IS_ERR(st))
return PTR_ERR(st);
if (!(st->mode & P9_DMSYMLINK)) {
retval = -EINVAL;
goto done;
}
/* copy extension buffer into buffer */
strncpy(buffer, st->extension, buflen);
P9_DPRINTK(P9_DEBUG_VFS,
"%s -> %s (%s)\n", dentry->d_name.name, st->extension, buffer);
retval = strnlen(buffer, buflen);
done:
kfree(st);
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();
P9_DPRINTK(P9_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[min(len, PATH_MAX-1)] = 0;
}
nd_set_link(nd, link);
return NULL;
}
/**
* v9fs_vfs_put_link - release a symlink path
* @dentry: dentry for symlink
* @nd: nameidata
* @p: unused
*
*/
static void
v9fs_vfs_put_link(struct dentry *dentry, struct nameidata *nd, void *p)
{
char *s = nd_get_link(nd);
P9_DPRINTK(P9_DEBUG_VFS, " %s %s\n", dentry->d_name.name,
IS_ERR(s) ? "<error>" : s);
if (!IS_ERR(s))
__putname(s);
}
/**
* v9fs_vfs_mkspecial - create a special file
* @dir: inode to create special file in
* @dentry: dentry to create
* @mode: mode to create special file
* @extension: 9p2000.u format extension string representing special file
*
*/
static int v9fs_vfs_mkspecial(struct inode *dir, struct dentry *dentry,
int mode, const char *extension)
{
u32 perm;
struct v9fs_session_info *v9ses;
struct p9_fid *fid;
v9ses = v9fs_inode2v9ses(dir);
if (!v9fs_proto_dotu(v9ses)) {
P9_DPRINTK(P9_DEBUG_ERROR, "not extended\n");
return -EPERM;
}
perm = unixmode2p9mode(v9ses, mode);
fid = v9fs_create(v9ses, dir, dentry, (char *) extension, perm,
P9_OREAD);
if (IS_ERR(fid))
return PTR_ERR(fid);
p9_client_clunk(fid);
return 0;
}
/**
* v9fs_vfs_symlink - helper function to create symlinks
* @dir: directory inode containing symlink
* @dentry: dentry for symlink
* @symname: symlink data
*
* See Also: 9P2000.u RFC for more information
*
*/
static int
v9fs_vfs_symlink(struct inode *dir, struct dentry *dentry, const char *symname)
{
P9_DPRINTK(P9_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
*
*/
static int
v9fs_vfs_link(struct dentry *old_dentry, struct inode *dir,
struct dentry *dentry)
{
int retval;
struct p9_fid *oldfid;
char *name;
P9_DPRINTK(P9_DEBUG_VFS,
" %lu,%s,%s\n", dir->i_ino, dentry->d_name.name,
old_dentry->d_name.name);
oldfid = v9fs_fid_clone(old_dentry);
if (IS_ERR(oldfid))
return PTR_ERR(oldfid);
name = __getname();
if (unlikely(!name)) {
retval = -ENOMEM;
goto clunk_fid;
}
sprintf(name, "%d\n", oldfid->fid);
retval = v9fs_vfs_mkspecial(dir, dentry, P9_DMLINK, name);
__putname(name);
clunk_fid:
p9_client_clunk(oldfid);
return retval;
}
/**
* v9fs_vfs_mknod - create a special file
* @dir: inode destination for new link
* @dentry: dentry for file
* @mode: mode for creation
* @rdev: 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;
P9_DPRINTK(P9_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 if (S_ISSOCK(mode))
*name = 0;
else {
__putname(name);
return -EINVAL;
}
retval = v9fs_vfs_mkspecial(dir, dentry, mode, name);
__putname(name);
return retval;
}
static const struct inode_operations v9fs_dir_inode_operations_dotu = {
.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,
.getattr = v9fs_vfs_getattr,
.setattr = v9fs_vfs_setattr,
};
static const struct inode_operations v9fs_dir_inode_operations_dotl = {
.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,
.getattr = v9fs_vfs_getattr_dotl,
.setattr = v9fs_vfs_setattr,
};
static const 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 const struct inode_operations v9fs_file_inode_operations = {
.getattr = v9fs_vfs_getattr,
.setattr = v9fs_vfs_setattr,
};
static const struct inode_operations v9fs_file_inode_operations_dotl = {
.getattr = v9fs_vfs_getattr_dotl,
.setattr = v9fs_vfs_setattr,
};
static const struct inode_operations v9fs_symlink_inode_operations = {
.readlink = generic_readlink,
.follow_link = v9fs_vfs_follow_link,
.put_link = v9fs_vfs_put_link,
.getattr = v9fs_vfs_getattr,
.setattr = v9fs_vfs_setattr,
};
static const struct inode_operations v9fs_symlink_inode_operations_dotl = {
.readlink = generic_readlink,
.follow_link = v9fs_vfs_follow_link,
.put_link = v9fs_vfs_put_link,
.getattr = v9fs_vfs_getattr_dotl,
.setattr = v9fs_vfs_setattr,
};
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