summaryrefslogtreecommitdiffstats
path: root/fs/9p
diff options
context:
space:
mode:
Diffstat (limited to 'fs/9p')
-rw-r--r--fs/9p/fid.c157
-rw-r--r--fs/9p/v9fs.c67
-rw-r--r--fs/9p/v9fs.h11
-rw-r--r--fs/9p/vfs_inode.c20
4 files changed, 195 insertions, 60 deletions
diff --git a/fs/9p/fid.c b/fs/9p/fid.c
index 15e05a1..b364da7 100644
--- a/fs/9p/fid.c
+++ b/fs/9p/fid.c
@@ -1,6 +1,7 @@
/*
* 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;
+}
diff --git a/fs/9p/v9fs.c b/fs/9p/v9fs.c
index 68f82be..89ee0ba 100644
--- a/fs/9p/v9fs.c
+++ b/fs/9p/v9fs.c
@@ -91,6 +91,8 @@ enum {
Opt_legacy, Opt_nodevmap,
/* Cache options */
Opt_cache_loose,
+ /* Access options */
+ Opt_access,
/* Error token */
Opt_err
};
@@ -108,6 +110,7 @@ static match_table_t tokens = {
{Opt_nodevmap, "nodevmap"},
{Opt_cache_loose, "cache=loose"},
{Opt_cache_loose, "loose"},
+ {Opt_access, "access=%s"},
{Opt_err, NULL}
};
@@ -125,10 +128,10 @@ static void v9fs_parse_options(struct v9fs_session_info *v9ses)
char *p;
int option;
int ret;
+ char *s, *e;
/* setup defaults */
v9ses->maxdata = 8192;
- v9ses->flags = V9FS_EXTENDED;
v9ses->afid = ~0;
v9ses->debug = 0;
v9ses->cache = 0;
@@ -172,10 +175,10 @@ static void v9fs_parse_options(struct v9fs_session_info *v9ses)
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->flags &= ~V9FS_EXTENDED;
@@ -186,6 +189,22 @@ static void v9fs_parse_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;
}
@@ -207,21 +226,22 @@ struct p9_fid *v9fs_session_init(struct v9fs_session_info *v9ses,
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);
+ 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);
@@ -255,8 +275,20 @@ 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;
@@ -264,6 +296,11 @@ 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:
@@ -284,8 +321,8 @@ 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);
}
diff --git a/fs/9p/v9fs.h b/fs/9p/v9fs.h
index 8e0999b..db4b419 100644
--- a/fs/9p/v9fs.h
+++ b/fs/9p/v9fs.h
@@ -36,10 +36,11 @@ struct v9fs_session_info {
unsigned int cache; /* cache mode */
char *options; /* copy of mount options */
- char *name; /* user name to mount as */
- char *remotename; /* name of remote hierarchy being mounted */
+ 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;
@@ -47,7 +48,11 @@ struct v9fs_session_info {
/* session flags */
enum {
- V9FS_EXTENDED,
+ 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 */
diff --git a/fs/9p/vfs_inode.c b/fs/9p/vfs_inode.c
index f08a35d..175b4d9 100644
--- a/fs/9p/vfs_inode.c
+++ b/fs/9p/vfs_inode.c
@@ -364,7 +364,7 @@ static int v9fs_remove(struct inode *dir, struct dentry *file, int rmdir)
file_inode = file->d_inode;
v9ses = v9fs_inode2v9ses(file_inode);
v9fid = v9fs_fid_clone(file);
- if(IS_ERR(v9fid))
+ if (IS_ERR(v9fid))
return PTR_ERR(v9fid);
return p9_client_remove(v9fid);
@@ -398,7 +398,7 @@ v9fs_create(struct v9fs_session_info *v9ses, struct inode *dir,
fid = NULL;
name = (char *) dentry->d_name.name;
dfid = v9fs_fid_clone(dentry->d_parent);
- if(IS_ERR(dfid)) {
+ if (IS_ERR(dfid)) {
err = PTR_ERR(dfid);
dfid = NULL;
goto error;
@@ -432,7 +432,7 @@ v9fs_create(struct v9fs_session_info *v9ses, struct inode *dir,
goto error;
}
- if(v9ses->cache)
+ if (v9ses->cache)
dentry->d_op = &v9fs_cached_dentry_operations;
else
dentry->d_op = &v9fs_dentry_operations;
@@ -593,7 +593,7 @@ static struct dentry *v9fs_vfs_lookup(struct inode *dir, struct dentry *dentry,
if (result < 0)
goto error;
- if((fid->qid.version)&&(v9ses->cache))
+ if ((fid->qid.version) && (v9ses->cache))
dentry->d_op = &v9fs_cached_dentry_operations;
else
dentry->d_op = &v9fs_dentry_operations;
@@ -658,17 +658,17 @@ v9fs_vfs_rename(struct inode *old_dir, struct dentry *old_dentry,
old_inode = old_dentry->d_inode;
v9ses = v9fs_inode2v9ses(old_inode);
oldfid = v9fs_fid_lookup(old_dentry);
- if(IS_ERR(oldfid))
+ if (IS_ERR(oldfid))
return PTR_ERR(oldfid);
olddirfid = v9fs_fid_clone(old_dentry->d_parent);
- if(IS_ERR(olddirfid)) {
+ if (IS_ERR(olddirfid)) {
retval = PTR_ERR(olddirfid);
goto done;
}
newdirfid = v9fs_fid_clone(new_dentry->d_parent);
- if(IS_ERR(newdirfid)) {
+ if (IS_ERR(newdirfid)) {
retval = PTR_ERR(newdirfid);
goto clunk_olddir;
}
@@ -682,7 +682,7 @@ v9fs_vfs_rename(struct inode *old_dir, struct dentry *old_dentry,
}
v9fs_blank_wstat(&wstat);
- wstat.muid = v9ses->name;
+ wstat.muid = v9ses->uname;
wstat.name = (char *) new_dentry->d_name.name;
retval = p9_client_wstat(oldfid, &wstat);
@@ -887,7 +887,7 @@ static int v9fs_readlink(struct dentry *dentry, char *buffer, int buflen)
retval = -EPERM;
v9ses = v9fs_inode2v9ses(dentry->d_inode);
fid = v9fs_fid_lookup(dentry);
- if(IS_ERR(fid))
+ if (IS_ERR(fid))
return PTR_ERR(fid);
if (!v9fs_extended(v9ses))
@@ -1070,7 +1070,7 @@ v9fs_vfs_link(struct dentry *old_dentry, struct inode *dir,
old_dentry->d_name.name);
oldfid = v9fs_fid_clone(old_dentry);
- if(IS_ERR(oldfid))
+ if (IS_ERR(oldfid))
return PTR_ERR(oldfid);
name = __getname();
OpenPOWER on IntegriCloud