Commit 9d8190f8 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ericvh/v9fs

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ericvh/v9fs:
  9p: remove sysctl
  9p: fix bad kconfig cross-dependency
  9p: soften invalidation in loose_mode
  9p: attach-per-user
  9p: rename uid and gid parameters
  9p: define session flags
  9p: Make transports dynamic
parents c2f73fd0 982c37cf
......@@ -35,12 +35,12 @@ For remote file server:
For Plan 9 From User Space applications (http://swtch.com/plan9)
mount -t 9p `namespace`/acme /mnt/9 -o proto=unix,uname=$USER
mount -t 9p `namespace`/acme /mnt/9 -o trans=unix,uname=$USER
OPTIONS
=======
proto=name select an alternative transport. Valid options are
trans=name select an alternative transport. Valid options are
currently:
unix - specifying a named pipe mount point
tcp - specifying a normal TCP/IP connection
......@@ -68,9 +68,9 @@ OPTIONS
0x40 = display transport debug
0x80 = display allocation debug
rfdno=n the file descriptor for reading with proto=fd
rfdno=n the file descriptor for reading with trans=fd
wfdno=n the file descriptor for writing with proto=fd
wfdno=n the file descriptor for writing with trans=fd
maxdata=n the number of bytes to use for 9p packet payload (msize)
......@@ -78,9 +78,9 @@ OPTIONS
noextend force legacy mode (no 9p2000.u semantics)
uid attempt to mount as a particular uid
dfltuid attempt to mount as a particular uid
gid attempt to mount with a particular gid
dfltgid attempt to mount with a particular gid
afid security channel - used by Plan 9 authentication protocols
......@@ -88,6 +88,16 @@ OPTIONS
This can be used to share devices/named pipes/sockets between
hosts. This functionality will be expanded in later versions.
access there are three access modes.
user = if a user tries to access a file on v9fs
filesystem for the first time, v9fs sends an
attach command (Tattach) for that user.
This is the default mode.
<uid> = allows only user with uid=<uid> to access
the files on the mounted filesystem
any = v9fs does single attach and performs all
operations as one user
RESOURCES
=========
......
/*
* V9FS FID Management
*
* Copyright (C) 2007 by Latchesar Ionkov <lucho@ionkov.net>
* Copyright (C) 2005, 2006 by Eric Van Hensbergen <ericvh@gmail.com>
*
* This program is free software; you can redistribute it and/or modify
......@@ -34,9 +35,9 @@
#include "fid.h"
/**
* v9fs_fid_insert - add a fid to a dentry
* v9fs_fid_add - add a fid to a dentry
* @dentry: dentry that the fid is being added to
* @fid: fid to add
* @dentry: dentry that it is being added to
*
*/
......@@ -66,52 +67,144 @@ int v9fs_fid_add(struct dentry *dentry, struct p9_fid *fid)
}
/**
* v9fs_fid_lookup - return a locked fid from a dentry
* v9fs_fid_find - retrieve a fid that belongs to the specified uid
* @dentry: dentry to look for fid in
*
* find a fid in the dentry, obtain its semaphore and return a reference to it.
* code calling lookup is responsible for releasing lock
*
* TODO: only match fids that have the same uid as current user
* @uid: return fid that belongs to the specified user
* @any: if non-zero, return any fid associated with the dentry
*
*/
struct p9_fid *v9fs_fid_lookup(struct dentry *dentry)
static struct p9_fid *v9fs_fid_find(struct dentry *dentry, u32 uid, int any)
{
struct v9fs_dentry *dent;
struct p9_fid *fid;
P9_DPRINTK(P9_DEBUG_VFS, " dentry: %s (%p)\n", dentry->d_iname, dentry);
dent = dentry->d_fsdata;
if (dent)
fid = list_entry(dent->fidlist.next, struct p9_fid, dlist);
else
fid = ERR_PTR(-EBADF);
struct p9_fid *fid, *ret;
P9_DPRINTK(P9_DEBUG_VFS, " dentry: %s (%p) uid %d any %d\n",
dentry->d_iname, dentry, uid, any);
dent = (struct v9fs_dentry *) dentry->d_fsdata;
ret = NULL;
if (dent) {
spin_lock(&dent->lock);
list_for_each_entry(fid, &dent->fidlist, dlist) {
if (any || fid->uid == uid) {
ret = fid;
break;
}
}
spin_unlock(&dent->lock);
}
P9_DPRINTK(P9_DEBUG_VFS, " fid: %p\n", fid);
return fid;
return ret;
}
/**
* v9fs_fid_clone - lookup the fid for a dentry, clone a private copy and
* release it
* v9fs_fid_lookup - lookup for a fid, try to walk if not found
* @dentry: dentry to look for fid in
*
* find a fid in the dentry and then clone to a new private fid
*
* TODO: only match fids that have the same uid as current user
*
* Look for a fid in the specified dentry for the current user.
* If no fid is found, try to create one walking from a fid from the parent
* dentry (if it has one), or the root dentry. If the user haven't accessed
* the fs yet, attach now and walk from the root.
*/
struct p9_fid *v9fs_fid_clone(struct dentry *dentry)
struct p9_fid *v9fs_fid_lookup(struct dentry *dentry)
{
struct p9_fid *ofid, *fid;
int i, n, l, clone, any, access;
u32 uid;
struct p9_fid *fid;
struct dentry *d, *ds;
struct v9fs_session_info *v9ses;
char **wnames, *uname;
v9ses = v9fs_inode2v9ses(dentry->d_inode);
access = v9ses->flags & V9FS_ACCESS_MASK;
switch (access) {
case V9FS_ACCESS_SINGLE:
case V9FS_ACCESS_USER:
uid = current->fsuid;
any = 0;
break;
case V9FS_ACCESS_ANY:
uid = v9ses->uid;
any = 1;
break;
default:
uid = ~0;
any = 0;
break;
}
P9_DPRINTK(P9_DEBUG_VFS, " dentry: %s (%p)\n", dentry->d_iname, dentry);
ofid = v9fs_fid_lookup(dentry);
if (IS_ERR(ofid))
return ofid;
fid = v9fs_fid_find(dentry, uid, any);
if (fid)
return fid;
ds = dentry->d_parent;
fid = v9fs_fid_find(ds, uid, any);
if (!fid) { /* walk from the root */
n = 0;
for (ds = dentry; !IS_ROOT(ds); ds = ds->d_parent)
n++;
fid = v9fs_fid_find(ds, uid, any);
if (!fid) { /* the user is not attached to the fs yet */
if (access == V9FS_ACCESS_SINGLE)
return ERR_PTR(-EPERM);
if (v9fs_extended(v9ses))
uname = NULL;
else
uname = v9ses->uname;
fid = p9_client_attach(v9ses->clnt, NULL, uname, uid,
v9ses->aname);
if (IS_ERR(fid))
return fid;
v9fs_fid_add(ds, fid);
}
} else /* walk from the parent */
n = 1;
if (ds == dentry)
return fid;
wnames = kmalloc(sizeof(char *) * n, GFP_KERNEL);
if (!wnames)
return ERR_PTR(-ENOMEM);
for (d = dentry, i = n; i >= 0; i--, d = d->d_parent)
wnames[i] = (char *) d->d_name.name;
clone = 1;
i = 0;
while (i < n) {
l = min(n - i, P9_MAXWELEM);
fid = p9_client_walk(fid, l, &wnames[i], clone);
if (!fid) {
kfree(wnames);
return fid;
}
i += l;
clone = 0;
}
fid = p9_client_walk(ofid, 0, NULL, 1);
kfree(wnames);
v9fs_fid_add(dentry, fid);
return fid;
}
struct p9_fid *v9fs_fid_clone(struct dentry *dentry)
{
struct p9_fid *fid, *ret;
fid = v9fs_fid_lookup(dentry);
if (IS_ERR(fid))
return fid;
ret = p9_client_walk(fid, 0, NULL, 1);
return ret;
}
......@@ -38,56 +38,41 @@
/*
* Option Parsing (code inspired by NFS code)
*
* NOTE: each transport will parse its own options
*/
enum {
/* Options that take integer arguments */
Opt_debug, Opt_port, Opt_msize, Opt_uid, Opt_gid, Opt_afid,
Opt_rfdno, Opt_wfdno,
Opt_debug, Opt_msize, Opt_dfltuid, Opt_dfltgid, Opt_afid,
/* String options */
Opt_uname, Opt_remotename,
Opt_uname, Opt_remotename, Opt_trans,
/* Options that take no arguments */
Opt_legacy, Opt_nodevmap, Opt_unix, Opt_tcp, Opt_fd, Opt_pci,
Opt_legacy, Opt_nodevmap,
/* Cache options */
Opt_cache_loose,
/* Access options */
Opt_access,
/* Error token */
Opt_err
};
static match_table_t tokens = {
{Opt_debug, "debug=%x"},
{Opt_port, "port=%u"},
{Opt_msize, "msize=%u"},
{Opt_uid, "uid=%u"},
{Opt_gid, "gid=%u"},
{Opt_dfltuid, "dfltuid=%u"},
{Opt_dfltgid, "dfltgid=%u"},
{Opt_afid, "afid=%u"},
{Opt_rfdno, "rfdno=%u"},
{Opt_wfdno, "wfdno=%u"},
{Opt_uname, "uname=%s"},
{Opt_remotename, "aname=%s"},
{Opt_unix, "proto=unix"},
{Opt_tcp, "proto=tcp"},
{Opt_fd, "proto=fd"},
#ifdef CONFIG_PCI_9P
{Opt_pci, "proto=pci"},
#endif
{Opt_tcp, "tcp"},
{Opt_unix, "unix"},
{Opt_fd, "fd"},
{Opt_trans, "trans=%s"},
{Opt_legacy, "noextend"},
{Opt_nodevmap, "nodevmap"},
{Opt_cache_loose, "cache=loose"},
{Opt_cache_loose, "loose"},
{Opt_access, "access=%s"},
{Opt_err, NULL}
};
extern struct p9_transport *p9pci_trans_create(void);
/*
* Parse option string.
*/
/**
* v9fs_parse_options - parse mount options into session structure
* @options: options string passed from mount
......@@ -95,23 +80,21 @@ extern struct p9_transport *p9pci_trans_create(void);
*
*/
static void v9fs_parse_options(char *options, struct v9fs_session_info *v9ses)
static void v9fs_parse_options(struct v9fs_session_info *v9ses)
{
char *p;
char *options = v9ses->options;
substring_t args[MAX_OPT_ARGS];
char *p;
int option;
int ret;
char *s, *e;
/* setup defaults */
v9ses->port = V9FS_PORT;
v9ses->maxdata = 9000;
v9ses->proto = PROTO_TCP;
v9ses->extended = 1;
v9ses->maxdata = 8192;
v9ses->afid = ~0;
v9ses->debug = 0;
v9ses->rfdno = ~0;
v9ses->wfdno = ~0;
v9ses->cache = 0;
v9ses->trans = v9fs_default_trans();
if (!options)
return;
......@@ -135,47 +118,29 @@ static void v9fs_parse_options(char *options, struct v9fs_session_info *v9ses)
p9_debug_level = option;
#endif
break;
case Opt_port:
v9ses->port = option;
break;
case Opt_msize:
v9ses->maxdata = option;
break;
case Opt_uid:
v9ses->uid = option;
case Opt_dfltuid:
v9ses->dfltuid = option;
break;
case Opt_gid:
v9ses->gid = option;
case Opt_dfltgid:
v9ses->dfltgid = option;
break;
case Opt_afid:
v9ses->afid = option;
break;
case Opt_rfdno:
v9ses->rfdno = option;
break;
case Opt_wfdno:
v9ses->wfdno = option;
break;
case Opt_tcp:
v9ses->proto = PROTO_TCP;
break;
case Opt_unix:
v9ses->proto = PROTO_UNIX;
break;
case Opt_pci:
v9ses->proto = PROTO_PCI;
break;
case Opt_fd:
v9ses->proto = PROTO_FD;
case Opt_trans:
v9ses->trans = v9fs_match_trans(&args[0]);
break;
case Opt_uname:
match_strcpy(v9ses->name, &args[0]);
match_strcpy(v9ses->uname, &args[0]);
break;
case Opt_remotename:
match_strcpy(v9ses->remotename, &args[0]);
match_strcpy(v9ses->aname, &args[0]);
break;
case Opt_legacy:
v9ses->extended = 0;
v9ses->flags &= ~V9FS_EXTENDED;
break;
case Opt_nodevmap:
v9ses->nodev = 1;
......@@ -183,6 +148,22 @@ static void v9fs_parse_options(char *options, struct v9fs_session_info *v9ses)
case Opt_cache_loose:
v9ses->cache = CACHE_LOOSE;
break;
case Opt_access:
s = match_strdup(&args[0]);
v9ses->flags &= ~V9FS_ACCESS_MASK;
if (strcmp(s, "user") == 0)
v9ses->flags |= V9FS_ACCESS_USER;
else if (strcmp(s, "any") == 0)
v9ses->flags |= V9FS_ACCESS_ANY;
else {
v9ses->flags |= V9FS_ACCESS_SINGLE;
v9ses->uid = simple_strtol(s, &e, 10);
if (*e != '\0')
v9ses->uid = ~0;
}
break;
default:
continue;
}
......@@ -201,56 +182,46 @@ struct p9_fid *v9fs_session_init(struct v9fs_session_info *v9ses,
const char *dev_name, char *data)
{
int retval = -EINVAL;
struct p9_transport *trans;
struct p9_trans *trans = NULL;
struct p9_fid *fid;
v9ses->name = __getname();
if (!v9ses->name)
v9ses->uname = __getname();
if (!v9ses->uname)
return ERR_PTR(-ENOMEM);
v9ses->remotename = __getname();
if (!v9ses->remotename) {
__putname(v9ses->name);
v9ses->aname = __getname();
if (!v9ses->aname) {
__putname(v9ses->uname);
return ERR_PTR(-ENOMEM);
}
strcpy(v9ses->name, V9FS_DEFUSER);
strcpy(v9ses->remotename, V9FS_DEFANAME);
v9fs_parse_options(data, v9ses);
switch (v9ses->proto) {
case PROTO_TCP:
trans = p9_trans_create_tcp(dev_name, v9ses->port);
break;
case PROTO_UNIX:
trans = p9_trans_create_unix(dev_name);
*v9ses->remotename = 0;
break;
case PROTO_FD:
trans = p9_trans_create_fd(v9ses->rfdno, v9ses->wfdno);
*v9ses->remotename = 0;
break;
#ifdef CONFIG_PCI_9P
case PROTO_PCI:
trans = p9pci_trans_create();
*v9ses->remotename = 0;
break;
#endif
default:
printk(KERN_ERR "v9fs: Bad mount protocol %d\n", v9ses->proto);
retval = -ENOPROTOOPT;
v9ses->flags = V9FS_EXTENDED | V9FS_ACCESS_USER;
strcpy(v9ses->uname, V9FS_DEFUSER);
strcpy(v9ses->aname, V9FS_DEFANAME);
v9ses->uid = ~0;
v9ses->dfltuid = V9FS_DEFUID;
v9ses->dfltgid = V9FS_DEFGID;
v9ses->options = kstrdup(data, GFP_KERNEL);
v9fs_parse_options(v9ses);
if (v9ses->trans == NULL) {
retval = -EPROTONOSUPPORT;
P9_DPRINTK(P9_DEBUG_ERROR,
"No transport defined or default transport\n");
goto error;
};
}
trans = v9ses->trans->create(dev_name, v9ses->options);
if (IS_ERR(trans)) {
retval = PTR_ERR(trans);
trans = NULL;
goto error;
}
if ((v9ses->maxdata+P9_IOHDRSZ) > v9ses->trans->maxsize)
v9ses->maxdata = v9ses->trans->maxsize-P9_IOHDRSZ;
v9ses->clnt = p9_client_create(trans, v9ses->maxdata + P9_IOHDRSZ,
v9ses->extended);
v9ses->clnt = p9_client_create(trans, v9ses->maxdata+P9_IOHDRSZ,
v9fs_extended(v9ses));
if (IS_ERR(v9ses->clnt)) {
retval = PTR_ERR(v9ses->clnt);
......@@ -259,8 +230,20 @@ struct p9_fid *v9fs_session_init(struct v9fs_session_info *v9ses,
goto error;
}
fid = p9_client_attach(v9ses->clnt, NULL, v9ses->name,
v9ses->remotename);
if (!v9ses->clnt->dotu)
v9ses->flags &= ~V9FS_EXTENDED;
/* for legacy mode, fall back to V9FS_ACCESS_ANY */
if (!v9fs_extended(v9ses) &&
((v9ses->flags&V9FS_ACCESS_MASK) == V9FS_ACCESS_USER)) {
v9ses->flags &= ~V9FS_ACCESS_MASK;
v9ses->flags |= V9FS_ACCESS_ANY;
v9ses->uid = ~0;
}
fid = p9_client_attach(v9ses->clnt, NULL, v9ses->uname, ~0,
v9ses->aname);
if (IS_ERR(fid)) {
retval = PTR_ERR(fid);
fid = NULL;
......@@ -268,6 +251,11 @@ struct p9_fid *v9fs_session_init(struct v9fs_session_info *v9ses,
goto error;
}
if ((v9ses->flags & V9FS_ACCESS_MASK) == V9FS_ACCESS_SINGLE)
fid->uid = v9ses->uid;
else
fid->uid = ~0;
return fid;
error:
......@@ -288,8 +276,9 @@ void v9fs_session_close(struct v9fs_session_info *v9ses)
v9ses->clnt = NULL;
}
__putname(v9ses->name);
__putname(v9ses->remotename);
__putname(v9ses->uname);
__putname(v9ses->aname);
kfree(v9ses->options);
}
/**
......@@ -311,7 +300,7 @@ extern int v9fs_error_init(void);
static int __init init_v9fs(void)
{
printk(KERN_INFO "Installing v9fs 9p2000 file system support\n");
/* TODO: Setup list of registered trasnport modules */
return register_filesystem(&v9fs_fs_type);
}
......
......@@ -29,31 +29,30 @@
struct v9fs_session_info {
/* options */
unsigned int maxdata;
unsigned char extended; /* set to 1 if we are using UNIX extensions */
unsigned char flags; /* session flags */
unsigned char nodev; /* set to 1 if no disable device mapping */
unsigned short port; /* port to connect to */
unsigned short debug; /* debug level */
unsigned short proto; /* protocol to use */
unsigned int afid; /* authentication fid */
unsigned int rfdno; /* read file descriptor number */
unsigned int wfdno; /* write file descriptor number */
unsigned int cache; /* cache mode */
char *name; /* user name to mount as */
char *remotename; /* name of remote hierarchy being mounted */
unsigned int uid; /* default uid/muid for legacy support */
unsigned int gid; /* default gid for legacy support */
char *options; /* copy of mount options */
char *uname; /* user name to mount as */
char *aname; /* name of remote hierarchy being mounted */
unsigned int dfltuid; /* default uid/muid for legacy support */
unsigned int dfltgid; /* default gid for legacy support */
u32 uid; /* if ACCESS_SINGLE, the uid that has access */
struct p9_trans_module *trans; /* 9p transport */
struct p9_client *clnt; /* 9p client */
struct dentry *debugfs_dir;
};
/* possible values of ->proto */
/* session flags */
enum {
PROTO_TCP,
PROTO_UNIX,
PROTO_FD,
PROTO_PCI,
V9FS_EXTENDED = 0x01, /* 9P2000.u */
V9FS_ACCESS_MASK = 0x06, /* access mask */
V9FS_ACCESS_SINGLE = 0x02, /* only one user can access the files */
V9FS_ACCESS_USER = 0x04, /* attache per user */
V9FS_ACCESS_ANY = 0x06, /* use the same attach for all users */
};
/* possible values of ->cache */
......@@ -73,11 +72,18 @@ void v9fs_session_cancel(struct v9fs_session_info *v9ses);
#define V9FS_MAGIC 0x01021997
/* other default globals */
#define V9FS_PORT 564
#define V9FS_PORT 564
#define V9FS_DEFUSER "nobody"
#define V9FS_DEFANAME ""
#define V9FS_DEFUID (-2)
#define V9FS_DEFGID (-2)
static inline struct v9fs_session_info *v9fs_inode2v9ses(struct inode *inode)
{
return (inode->i_sb->s_fs_info);
}
static inline int v9fs_extended(struct v9fs_session_info *v9ses)
{
return v9ses->flags & V9FS_EXTENDED;
}
......@@ -162,15 +162,17 @@ v9fs_file_write(struct file *filp, const char __user * data,
fid = filp->private_data;
ret = p9_client_uwrite(fid, data, *offset, count<