9p: Define and implement TSYMLINK for 9P2000.L

Create a symbolic link

SYNOPSIS

size[4] Tsymlink tag[2] fid[4] name[s] symtgt[s] gid[4]

size[4] Rsymlink tag[2] qid[13]

DESCRIPTION

Create a symbolic link named 'name' pointing to 'symtgt'.
gid represents the effective group id of the caller.
The  permissions of a symbolic link are irrelevant hence it is omitted
from the protocol.

Signed-off-by: Venkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
Reviewed-by: Sripathi Kodi <sripathik@in.ibm.com>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
This commit is contained in:
Venkateswararao Jujjuri (JV) 2010-06-09 15:59:31 -07:00 committed by Eric Van Hensbergen
parent 652df9a7fd
commit 50cc42ff3d
4 changed files with 137 additions and 4 deletions

View file

@ -1245,7 +1245,7 @@ static int v9fs_readlink(struct dentry *dentry, char *buffer, int buflen)
if (IS_ERR(fid))
return PTR_ERR(fid);
if (!v9fs_proto_dotu(v9ses))
if (!v9fs_proto_dotu(v9ses) && !v9fs_proto_dotl(v9ses))
return -EBADF;
st = p9_client_stat(fid);
@ -1350,6 +1350,99 @@ static int v9fs_vfs_mkspecial(struct inode *dir, struct dentry *dentry,
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);
if (gid < 0) {
P9_DPRINTK(P9_DEBUG_VFS, "v9fs_get_egid failed %d\n", gid);
goto error;
}
/* 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
@ -1527,7 +1620,7 @@ 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_dotl,
.link = v9fs_vfs_link,
.unlink = v9fs_vfs_unlink,
.mkdir = v9fs_vfs_mkdir,
.rmdir = v9fs_vfs_rmdir,
@ -1540,8 +1633,8 @@ static const struct inode_operations v9fs_dir_inode_operations_dotu = {
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,
.link = v9fs_vfs_link_dotl,
.symlink = v9fs_vfs_symlink_dotl,
.unlink = v9fs_vfs_unlink,
.mkdir = v9fs_vfs_mkdir,
.rmdir = v9fs_vfs_rmdir,

View file

@ -88,6 +88,8 @@ do { \
* enum p9_msg_t - 9P message types
* @P9_TSTATFS: file system status request
* @P9_RSTATFS: file system status response
* @P9_TSYMLINK: make symlink request
* @P9_RSYMLINK: make symlink response
* @P9_TRENAME: rename request
* @P9_RRENAME: rename response
* @P9_TVERSION: version handshake request
@ -131,6 +133,8 @@ do { \
enum p9_msg_t {
P9_TSTATFS = 8,
P9_RSTATFS,
P9_TSYMLINK = 16,
P9_RSYMLINK,
P9_TRENAME = 20,
P9_RRENAME,
P9_TGETATTR = 24,

View file

@ -227,6 +227,8 @@ int p9_client_open(struct p9_fid *fid, int mode);
int p9_client_fcreate(struct p9_fid *fid, char *name, u32 perm, int mode,
char *extension);
int p9_client_link(struct p9_fid *fid, struct p9_fid *oldfid, char *newname);
int p9_client_symlink(struct p9_fid *fid, char *name, char *symname, gid_t gid,
struct p9_qid *qid);
int p9_client_clunk(struct p9_fid *fid);
int p9_client_remove(struct p9_fid *fid);
int p9_client_read(struct p9_fid *fid, char *data, char __user *udata,

View file

@ -1095,6 +1095,40 @@ int p9_client_fcreate(struct p9_fid *fid, char *name, u32 perm, int mode,
}
EXPORT_SYMBOL(p9_client_fcreate);
int p9_client_symlink(struct p9_fid *dfid, char *name, char *symtgt, gid_t gid,
struct p9_qid *qid)
{
int err = 0;
struct p9_client *clnt;
struct p9_req_t *req;
P9_DPRINTK(P9_DEBUG_9P, ">>> TSYMLINK dfid %d name %s symtgt %s\n",
dfid->fid, name, symtgt);
clnt = dfid->clnt;
req = p9_client_rpc(clnt, P9_TSYMLINK, "dssd", dfid->fid, name, symtgt,
gid);
if (IS_ERR(req)) {
err = PTR_ERR(req);
goto error;
}
err = p9pdu_readf(req->rc, clnt->proto_version, "Q", qid);
if (err) {
p9pdu_dump(1, req->rc);
goto free_and_error;
}
P9_DPRINTK(P9_DEBUG_9P, "<<< RSYMLINK qid %x.%llx.%x\n",
qid->type, (unsigned long long)qid->path, qid->version);
free_and_error:
p9_free_req(clnt, req);
error:
return err;
}
EXPORT_SYMBOL(p9_client_symlink);
int p9_client_link(struct p9_fid *dfid, struct p9_fid *oldfid, char *newname)
{
struct p9_client *clnt;