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fa0d7e3de6
kernel_optimize_test/fs/9p/vfs_inode.c
Nick Piggin fa0d7e3de6 fs: icache RCU free inodes 
RCU free the struct inode. This will allow:

- Subsequent store-free path walking patch. The inode must be consulted for
  permissions when walking, so an RCU inode reference is a must.
- sb_inode_list_lock to be moved inside i_lock because sb list walkers who want
  to take i_lock no longer need to take sb_inode_list_lock to walk the list in
  the first place. This will simplify and optimize locking.
- Could remove some nested trylock loops in dcache code
- Could potentially simplify things a bit in VM land. Do not need to take the
  page lock to follow page->mapping.

The downsides of this is the performance cost of using RCU. In a simple
creat/unlink microbenchmark, performance drops by about 10% due to inability to
reuse cache-hot slab objects. As iterations increase and RCU freeing starts
kicking over, this increases to about 20%.

In cases where inode lifetimes are longer (ie. many inodes may be allocated
during the average life span of a single inode), a lot of this cache reuse is
not applicable, so the regression caused by this patch is smaller.

The cache-hot regression could largely be avoided by using SLAB_DESTROY_BY_RCU,
however this adds some complexity to list walking and store-free path walking,
so I prefer to implement this at a later date, if it is shown to be a win in
real situations. I haven't found a regression in any non-micro benchmark so I
doubt it will be a problem.

Signed-off-by: Nick Piggin <npiggin@kernel.dk>
2011-01-07 17:50:26 +11:00

2143 lines
49 KiB
C
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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 <linux/xattr.h>
#include <linux/posix_acl.h>
#include <net/9p/9p.h>
#include <net/9p/client.h>
#include "v9fs.h"
#include "v9fs_vfs.h"
#include "fid.h"
#include "cache.h"
#include "xattr.h"
#include "acl.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;
static int
v9fs_vfs_mknod_dotl(struct inode *dir, struct dentry *dentry, int omode,
dev_t rdev);
/**
* 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
*
*/
static void v9fs_i_callback(struct rcu_head *head)
{
struct inode *inode = container_of(head, struct inode, i_rcu);
INIT_LIST_HEAD(&inode->i_dentry);
kmem_cache_free(vcookie_cache, v9fs_inode2cookie(inode));
}
void v9fs_destroy_inode(struct inode *inode)
{
call_rcu(&inode->i_rcu, v9fs_i_callback);
}
#endif
/**
* v9fs_get_fsgid_for_create - Helper function to get the gid for creating a
* new file system object. This checks the S_ISGID to determine the owning
* group of the new file system object.
*/
static gid_t v9fs_get_fsgid_for_create(struct inode *dir_inode)
{
BUG_ON(dir_inode == NULL);
if (dir_inode->i_mode & S_ISGID) {
/* set_gid bit is set.*/
return dir_inode->i_gid;
}
return current_fsgid();
}
/**
* v9fs_dentry_from_dir_inode - helper function to get the dentry from
* dir inode.
*
*/
static struct dentry *v9fs_dentry_from_dir_inode(struct inode *inode)
{
struct dentry *dentry;
spin_lock(&dcache_inode_lock);
/* Directory should have only one entry. */
BUG_ON(S_ISDIR(inode->i_mode) && !list_is_singular(&inode->i_dentry));
dentry = list_entry(inode->i_dentry.next, struct dentry, d_alias);
spin_unlock(&dcache_inode_lock);
return dentry;
}
/**
* 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_dotl(v9ses)) {
inode->i_op = &v9fs_file_inode_operations_dotl;
inode->i_fop = &v9fs_file_operations_dotl;
} else if (v9fs_proto_dotu(v9ses)) {
inode->i_op = &v9fs_file_inode_operations;
inode->i_fop = &v9fs_file_operations;
} else {
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_evict_inode(struct inode *inode)
{
truncate_inode_pages(inode->i_mapping, 0);
end_writeback(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
err = v9fs_get_acl(ret, fid);
if (err) {
iput(ret);
goto error;
}
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;
}
/**
* 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_dotl - VFS hook to create files for 9P2000.L protocol.
* @dir: directory inode that is being created
* @dentry: dentry that is being deleted
* @mode: create permissions
* @nd: path information
*
*/
static int
v9fs_vfs_create_dotl(struct inode *dir, struct dentry *dentry, int omode,
struct nameidata *nd)
{
int err = 0;
char *name = NULL;
gid_t gid;
int flags;
mode_t mode;
struct v9fs_session_info *v9ses;
struct p9_fid *fid = NULL;
struct p9_fid *dfid, *ofid;
struct file *filp;
struct p9_qid qid;
struct inode *inode;
struct posix_acl *pacl = NULL, *dacl = NULL;
v9ses = v9fs_inode2v9ses(dir);
if (nd && nd->flags & LOOKUP_OPEN)
flags = nd->intent.open.flags - 1;
else {
/*
* create call without LOOKUP_OPEN is due
* to mknod of regular files. So use mknod
* operation.
*/
return v9fs_vfs_mknod_dotl(dir, dentry, omode, 0);
}
name = (char *) dentry->d_name.name;
P9_DPRINTK(P9_DEBUG_VFS, "v9fs_vfs_create_dotl: name:%s flags:0x%x "
"mode:0x%x\n", name, flags, omode);
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;
}
/* 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;
}
gid = v9fs_get_fsgid_for_create(dir);
mode = omode;
/* Update mode based on ACL value */
err = v9fs_acl_mode(dir, &mode, &dacl, &pacl);
if (err) {
P9_DPRINTK(P9_DEBUG_VFS,
"Failed to get acl values in creat %d\n", err);
goto error;
}
err = p9_client_create_dotl(ofid, name, flags, mode, gid, &qid);
if (err < 0) {
P9_DPRINTK(P9_DEBUG_VFS,
"p9_client_open_dotl failed in creat %d\n",
err);
goto error;
}
/* instantiate inode and assign the unopened fid to the dentry */
if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE ||
(nd && nd->flags & LOOKUP_OPEN)) {
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;
}
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;
}
dentry->d_op = &v9fs_cached_dentry_operations;
d_instantiate(dentry, inode);
err = v9fs_fid_add(dentry, fid);
if (err < 0)
goto error;
/* The fid would get clunked via a dput */
fid = NULL;
} else {
/*
* Not in cached mode. No need to populate
* inode with stat. We need to get an inode
* so that we can set the acl with dentry
*/
inode = v9fs_get_inode(dir->i_sb, mode);
if (IS_ERR(inode)) {
err = PTR_ERR(inode);
goto error;
}
dentry->d_op = &v9fs_dentry_operations;
d_instantiate(dentry, inode);
}
/* Now set the ACL based on the default value */
v9fs_set_create_acl(dentry, dacl, pacl);
/* 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, generic_file_open);
if (IS_ERR(filp)) {
p9_client_clunk(ofid);
return PTR_ERR(filp);
}
filp->private_data = ofid;
} else
p9_client_clunk(ofid);
return 0;
error:
if (ofid)
p9_client_clunk(ofid);
if (fid)
p9_client_clunk(fid);
return 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, generic_file_open);
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_mkdir_dotl - 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_dotl(struct inode *dir,
struct dentry *dentry, int omode)
{
int err;
struct v9fs_session_info *v9ses;
struct p9_fid *fid = NULL, *dfid = NULL;
gid_t gid;
char *name;
mode_t mode;
struct inode *inode;
struct p9_qid qid;
struct dentry *dir_dentry;
struct posix_acl *dacl = NULL, *pacl = NULL;
P9_DPRINTK(P9_DEBUG_VFS, "name %s\n", dentry->d_name.name);
err = 0;
v9ses = v9fs_inode2v9ses(dir);
omode |= S_IFDIR;
if (dir->i_mode & S_ISGID)
omode |= S_ISGID;
dir_dentry = v9fs_dentry_from_dir_inode(dir);
dfid = v9fs_fid_lookup(dir_dentry);
if (IS_ERR(dfid)) {
err = PTR_ERR(dfid);
P9_DPRINTK(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
dfid = NULL;
goto error;
}
gid = v9fs_get_fsgid_for_create(dir);
mode = omode;
/* Update mode based on ACL value */
err = v9fs_acl_mode(dir, &mode, &dacl, &pacl);
if (err) {
P9_DPRINTK(P9_DEBUG_VFS,
"Failed to get acl values in mkdir %d\n", err);
goto error;
}
name = (char *) dentry->d_name.name;
err = p9_client_mkdir_dotl(dfid, name, mode, gid, &qid);
if (err < 0)
goto error;
/* instantiate inode and assign the unopened fid to the dentry */
if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
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;
}
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;
}
dentry->d_op = &v9fs_cached_dentry_operations;
d_instantiate(dentry, inode);
err = v9fs_fid_add(dentry, fid);
if (err < 0)
goto error;
fid = NULL;
} else {
/*
* Not in cached mode. No need to populate
* inode with stat. We need to get an inode
* so that we can set the acl with dentry
*/
inode = v9fs_get_inode(dir->i_sb, mode);
if (IS_ERR(inode)) {
err = PTR_ERR(inode);
goto error;
}
dentry->d_op = &v9fs_dentry_operations;
d_instantiate(dentry, inode);
}
/* Now set the ACL based on the default value */
v9fs_set_create_acl(dentry, dacl, pacl);
error:
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);
/* We can walk d_parent because we hold the dir->i_mutex */
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_iput;
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_iput:
iput(inode);
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;
}
down_write(&v9ses->rename_sem);
if (v9fs_proto_dotl(v9ses)) {
retval = p9_client_rename(oldfid, newdirfid,
(char *) new_dentry->d_name.name);
if (retval != -ENOSYS)
goto clunk_newdir;
}
if (old_dentry->d_parent != new_dentry->d_parent) {
/*
* 9P .u can only handle file rename in the same directory
*/
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:
if (!retval)
/* successful rename */
d_move(old_dentry, new_dentry);
up_write(&v9ses->rename_sem);
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);
p9stat_free(st);
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)
return retval;
if ((iattr->ia_valid & ATTR_SIZE) &&
iattr->ia_size != i_size_read(dentry->d_inode)) {
retval = vmtruncate(dentry->d_inode, iattr->ia_size);
if (retval)
return retval;
}
setattr_copy(dentry->d_inode, iattr);
mark_inode_dirty(dentry->d_inode);
return 0;
}
/**
* v9fs_vfs_setattr_dotl - set file metadata
* @dentry: file whose metadata to set
* @iattr: metadata assignment structure
*
*/
int v9fs_vfs_setattr_dotl(struct dentry *dentry, struct iattr *iattr)
{
int retval;
struct v9fs_session_info *v9ses;
struct p9_fid *fid;
struct p9_iattr_dotl p9attr;
P9_DPRINTK(P9_DEBUG_VFS, "\n");
retval = inode_change_ok(dentry->d_inode, iattr);
if (retval)
return retval;
p9attr.valid = iattr->ia_valid;
p9attr.mode = iattr->ia_mode;
p9attr.uid = iattr->ia_uid;
p9attr.gid = iattr->ia_gid;
p9attr.size = iattr->ia_size;
p9attr.atime_sec = iattr->ia_atime.tv_sec;
p9attr.atime_nsec = iattr->ia_atime.tv_nsec;
p9attr.mtime_sec = iattr->ia_mtime.tv_sec;
p9attr.mtime_nsec = iattr->ia_mtime.tv_nsec;
retval = -EPERM;
v9ses = v9fs_inode2v9ses(dentry->d_inode);
fid = v9fs_fid_lookup(dentry);
if (IS_ERR(fid))
return PTR_ERR(fid);
retval = p9_client_setattr(fid, &p9attr);
if (retval < 0)
return retval;
if ((iattr->ia_valid & ATTR_SIZE) &&
iattr->ia_size != i_size_read(dentry->d_inode)) {
retval = vmtruncate(dentry->d_inode, iattr->ia_size);
if (retval)
return retval;
}
setattr_copy(dentry->d_inode, iattr);
mark_inode_dirty(dentry->d_inode);
if (iattr->ia_valid & ATTR_MODE) {
/* We also want to update ACL when we update mode bits */
retval = v9fs_acl_chmod(dentry);
if (retval < 0)
return retval;
}
return 0;
}
/**
* 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:
p9stat_free(st);
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_dotl - helper function to create symlinks
* @dir: directory inode containing symlink
* @dentry: dentry for symlink
* @symname: symlink data
*
* See Also: 9P2000.L RFC for more information
*
*/
static int
v9fs_vfs_symlink_dotl(struct inode *dir, struct dentry *dentry,
const char *symname)
{
struct v9fs_session_info *v9ses;
struct p9_fid *dfid;
struct p9_fid *fid = NULL;
struct inode *inode;
struct p9_qid qid;
char *name;
int err;
gid_t gid;
name = (char *) dentry->d_name.name;
P9_DPRINTK(P9_DEBUG_VFS, "v9fs_vfs_symlink_dotl : %lu,%s,%s\n",
dir->i_ino, name, symname);
v9ses = v9fs_inode2v9ses(dir);
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;
}
gid = v9fs_get_fsgid_for_create(dir);
/* Server doesn't alter fid on TSYMLINK. Hence no need to clone it. */
err = p9_client_symlink(dfid, name, (char *)symname, gid, &qid);
if (err < 0) {
P9_DPRINTK(P9_DEBUG_VFS, "p9_client_symlink failed %d\n", err);
goto error;
}
if (v9ses->cache) {
/* Now walk from the parent so we can get an 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 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;
}
dentry->d_op = &v9fs_cached_dentry_operations;
d_instantiate(dentry, inode);
err = v9fs_fid_add(dentry, fid);
if (err < 0)
goto error;
fid = NULL;
} else {
/* Not in cached mode. No need to populate inode with stat */
inode = v9fs_get_inode(dir->i_sb, S_IFLNK);
if (IS_ERR(inode)) {
err = PTR_ERR(inode);
goto error;
}
dentry->d_op = &v9fs_dentry_operations;
d_instantiate(dentry, inode);
}
error:
if (fid)
p9_client_clunk(fid);
return err;
}
/**
* 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_link_dotl - create a hardlink for dotl
* @old_dentry: dentry for file to link to
* @dir: inode destination for new link
* @dentry: dentry for link
*
*/
static int
v9fs_vfs_link_dotl(struct dentry *old_dentry, struct inode *dir,
struct dentry *dentry)
{
int err;
struct p9_fid *dfid, *oldfid;
char *name;
struct v9fs_session_info *v9ses;
struct dentry *dir_dentry;
P9_DPRINTK(P9_DEBUG_VFS, "dir ino: %lu, old_name: %s, new_name: %s\n",
dir->i_ino, old_dentry->d_name.name,
dentry->d_name.name);
v9ses = v9fs_inode2v9ses(dir);
dir_dentry = v9fs_dentry_from_dir_inode(dir);
dfid = v9fs_fid_lookup(dir_dentry);
if (IS_ERR(dfid))
return PTR_ERR(dfid);
oldfid = v9fs_fid_lookup(old_dentry);
if (IS_ERR(oldfid))
return PTR_ERR(oldfid);
name = (char *) dentry->d_name.name;
err = p9_client_link(dfid, oldfid, (char *)dentry->d_name.name);
if (err < 0) {
P9_DPRINTK(P9_DEBUG_VFS, "p9_client_link failed %d\n", err);
return err;
}
if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
/* Get the latest stat info from server. */
struct p9_fid *fid;
struct p9_stat_dotl *st;
fid = v9fs_fid_lookup(old_dentry);
if (IS_ERR(fid))
return PTR_ERR(fid);
st = p9_client_getattr_dotl(fid, P9_STATS_BASIC);
if (IS_ERR(st))
return PTR_ERR(st);
v9fs_stat2inode_dotl(st, old_dentry->d_inode);
kfree(st);
} else {
/* Caching disabled. No need to get upto date stat info.
* This dentry will be released immediately. So, just hold the
* inode
*/
ihold(old_dentry->d_inode);
}
dentry->d_op = old_dentry->d_op;
d_instantiate(dentry, old_dentry->d_inode);
return err;
}
/**
* 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;
}
/**
* v9fs_vfs_mknod_dotl - 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_dotl(struct inode *dir, struct dentry *dentry, int omode,
dev_t rdev)
{
int err;
char *name;
mode_t mode;
struct v9fs_session_info *v9ses;
struct p9_fid *fid = NULL, *dfid = NULL;
struct inode *inode;
gid_t gid;
struct p9_qid qid;
struct dentry *dir_dentry;
struct posix_acl *dacl = NULL, *pacl = NULL;
P9_DPRINTK(P9_DEBUG_VFS,
" %lu,%s mode: %x MAJOR: %u MINOR: %u\n", dir->i_ino,
dentry->d_name.name, omode, MAJOR(rdev), MINOR(rdev));
if (!new_valid_dev(rdev))
return -EINVAL;
v9ses = v9fs_inode2v9ses(dir);
dir_dentry = v9fs_dentry_from_dir_inode(dir);
dfid = v9fs_fid_lookup(dir_dentry);
if (IS_ERR(dfid)) {
err = PTR_ERR(dfid);
P9_DPRINTK(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
dfid = NULL;
goto error;
}
gid = v9fs_get_fsgid_for_create(dir);
mode = omode;
/* Update mode based on ACL value */
err = v9fs_acl_mode(dir, &mode, &dacl, &pacl);
if (err) {
P9_DPRINTK(P9_DEBUG_VFS,
"Failed to get acl values in mknod %d\n", err);
goto error;
}
name = (char *) dentry->d_name.name;
err = p9_client_mknod_dotl(dfid, name, mode, rdev, gid, &qid);
if (err < 0)
goto error;
/* instantiate inode and assign the unopened fid to the dentry */
if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
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;
}
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;
}
dentry->d_op = &v9fs_cached_dentry_operations;
d_instantiate(dentry, inode);
err = v9fs_fid_add(dentry, fid);
if (err < 0)
goto error;
fid = NULL;
} else {
/*
* Not in cached mode. No need to populate inode with stat.
* socket syscall returns a fd, so we need instantiate
*/
inode = v9fs_get_inode(dir->i_sb, mode);
if (IS_ERR(inode)) {
err = PTR_ERR(inode);
goto error;
}
dentry->d_op = &v9fs_dentry_operations;
d_instantiate(dentry, inode);
}
/* Now set the ACL based on the default value */
v9fs_set_create_acl(dentry, dacl, pacl);
error:
if (fid)
p9_client_clunk(fid);
return err;
}
static int
v9fs_vfs_readlink_dotl(struct dentry *dentry, char *buffer, int buflen)
{
int retval;
struct p9_fid *fid;
char *target = NULL;
P9_DPRINTK(P9_DEBUG_VFS, " %s\n", dentry->d_name.name);
retval = -EPERM;
fid = v9fs_fid_lookup(dentry);
if (IS_ERR(fid))
return PTR_ERR(fid);
retval = p9_client_readlink(fid, &target);
if (retval < 0)
return retval;
strncpy(buffer, target, buflen);
P9_DPRINTK(P9_DEBUG_VFS, "%s -> %s\n", dentry->d_name.name, buffer);
retval = strnlen(buffer, buflen);
return retval;
}
/**
* v9fs_vfs_follow_link_dotl - follow a symlink path
* @dentry: dentry for symlink
* @nd: nameidata
*
*/
static void *
v9fs_vfs_follow_link_dotl(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_vfs_readlink_dotl(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;
}
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_dotl,
.lookup = v9fs_vfs_lookup,
.link = v9fs_vfs_link_dotl,
.symlink = v9fs_vfs_symlink_dotl,
.unlink = v9fs_vfs_unlink,
.mkdir = v9fs_vfs_mkdir_dotl,
.rmdir = v9fs_vfs_rmdir,
.mknod = v9fs_vfs_mknod_dotl,
.rename = v9fs_vfs_rename,
.getattr = v9fs_vfs_getattr_dotl,
.setattr = v9fs_vfs_setattr_dotl,
.setxattr = generic_setxattr,
.getxattr = generic_getxattr,
.removexattr = generic_removexattr,
.listxattr = v9fs_listxattr,
.check_acl = v9fs_check_acl,
};
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_dotl,
.setxattr = generic_setxattr,
.getxattr = generic_getxattr,
.removexattr = generic_removexattr,
.listxattr = v9fs_listxattr,
.check_acl = v9fs_check_acl,
};
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 = v9fs_vfs_readlink_dotl,
.follow_link = v9fs_vfs_follow_link_dotl,
.put_link = v9fs_vfs_put_link,
.getattr = v9fs_vfs_getattr_dotl,
.setattr = v9fs_vfs_setattr_dotl,
.setxattr = generic_setxattr,
.getxattr = generic_getxattr,
.removexattr = generic_removexattr,
.listxattr = v9fs_listxattr,
};
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