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-rw-r--r--fs/nfs/namespace.c167
1 files changed, 102 insertions, 65 deletions
diff --git a/fs/nfs/namespace.c b/fs/nfs/namespace.c
index f32b8603dca..b5a0afc3ee1 100644
--- a/fs/nfs/namespace.c
+++ b/fs/nfs/namespace.c
@@ -7,6 +7,7 @@
* NFS namespace
*/
+#include <linux/module.h>
#include <linux/dcache.h>
#include <linux/gfp.h>
#include <linux/mount.h>
@@ -15,6 +16,7 @@
#include <linux/string.h>
#include <linux/sunrpc/clnt.h>
#include <linux/vfs.h>
+#include <linux/sunrpc/gss_api.h>
#include "internal.h"
#define NFSDBG_FACILITY NFSDBG_VFS
@@ -25,33 +27,33 @@ static LIST_HEAD(nfs_automount_list);
static DECLARE_DELAYED_WORK(nfs_automount_task, nfs_expire_automounts);
int nfs_mountpoint_expiry_timeout = 500 * HZ;
-static struct vfsmount *nfs_do_submount(const struct vfsmount *mnt_parent,
- const struct dentry *dentry,
- struct nfs_fh *fh,
- struct nfs_fattr *fattr);
-
/*
* nfs_path - reconstruct the path given an arbitrary dentry
- * @base - arbitrary string to prepend to the path
- * @droot - pointer to root dentry for mountpoint
+ * @base - used to return pointer to the end of devname part of path
* @dentry - pointer to dentry
* @buffer - result buffer
* @buflen - length of buffer
+ * @flags - options (see below)
*
- * Helper function for constructing the path from the
- * root dentry to an arbitrary hashed dentry.
+ * Helper function for constructing the server pathname
+ * by arbitrary hashed dentry.
*
* This is mainly for use in figuring out the path on the
- * server side when automounting on top of an existing partition.
+ * server side when automounting on top of an existing partition
+ * and in generating /proc/mounts and friends.
+ *
+ * Supported flags:
+ * NFS_PATH_CANONICAL: ensure there is exactly one slash after
+ * the original device (export) name
+ * (if unset, the original name is returned verbatim)
*/
-char *nfs_path(const char *base,
- const struct dentry *droot,
- const struct dentry *dentry,
- char *buffer, ssize_t buflen)
+char *nfs_path(char **p, struct dentry *dentry, char *buffer, ssize_t buflen,
+ unsigned flags)
{
char *end;
int namelen;
unsigned seq;
+ const char *base;
rename_retry:
end = buffer+buflen;
@@ -60,7 +62,10 @@ rename_retry:
seq = read_seqbegin(&rename_lock);
rcu_read_lock();
- while (!IS_ROOT(dentry) && dentry != droot) {
+ while (1) {
+ spin_lock(&dentry->d_lock);
+ if (IS_ROOT(dentry))
+ break;
namelen = dentry->d_name.len;
buflen -= namelen + 1;
if (buflen < 0)
@@ -68,33 +73,56 @@ rename_retry:
end -= namelen;
memcpy(end, dentry->d_name.name, namelen);
*--end = '/';
+ spin_unlock(&dentry->d_lock);
dentry = dentry->d_parent;
}
- rcu_read_unlock();
- if (read_seqretry(&rename_lock, seq))
+ if (read_seqretry(&rename_lock, seq)) {
+ spin_unlock(&dentry->d_lock);
+ rcu_read_unlock();
goto rename_retry;
- if (*end != '/') {
- if (--buflen < 0)
+ }
+ if ((flags & NFS_PATH_CANONICAL) && *end != '/') {
+ if (--buflen < 0) {
+ spin_unlock(&dentry->d_lock);
+ rcu_read_unlock();
goto Elong;
+ }
*--end = '/';
}
+ *p = end;
+ base = dentry->d_fsdata;
+ if (!base) {
+ spin_unlock(&dentry->d_lock);
+ rcu_read_unlock();
+ WARN_ON(1);
+ return end;
+ }
namelen = strlen(base);
- /* Strip off excess slashes in base string */
- while (namelen > 0 && base[namelen - 1] == '/')
- namelen--;
+ if (flags & NFS_PATH_CANONICAL) {
+ /* Strip off excess slashes in base string */
+ while (namelen > 0 && base[namelen - 1] == '/')
+ namelen--;
+ }
buflen -= namelen;
- if (buflen < 0)
+ if (buflen < 0) {
+ spin_unlock(&dentry->d_lock);
+ rcu_read_unlock();
goto Elong;
+ }
end -= namelen;
memcpy(end, base, namelen);
+ spin_unlock(&dentry->d_lock);
+ rcu_read_unlock();
return end;
Elong_unlock:
+ spin_unlock(&dentry->d_lock);
rcu_read_unlock();
if (read_seqretry(&rename_lock, seq))
goto rename_retry;
Elong:
return ERR_PTR(-ENAMETOOLONG);
}
+EXPORT_SYMBOL_GPL(nfs_path);
/*
* nfs_d_automount - Handle crossing a mountpoint on the server
@@ -112,10 +140,8 @@ struct vfsmount *nfs_d_automount(struct path *path)
{
struct vfsmount *mnt;
struct nfs_server *server = NFS_SERVER(path->dentry->d_inode);
- struct dentry *parent;
struct nfs_fh *fh = NULL;
struct nfs_fattr *fattr = NULL;
- int err;
dprintk("--> nfs_d_automount()\n");
@@ -131,21 +157,7 @@ struct vfsmount *nfs_d_automount(struct path *path)
dprintk("%s: enter\n", __func__);
- /* Look it up again to get its attributes */
- parent = dget_parent(path->dentry);
- err = server->nfs_client->rpc_ops->lookup(parent->d_inode,
- &path->dentry->d_name,
- fh, fattr);
- dput(parent);
- if (err != 0) {
- mnt = ERR_PTR(err);
- goto out;
- }
-
- if (fattr->valid & NFS_ATTR_FATTR_V4_REFERRAL)
- mnt = nfs_do_refmount(path->mnt, path->dentry);
- else
- mnt = nfs_do_submount(path->mnt, path->dentry, fh, fattr);
+ mnt = server->nfs_client->rpc_ops->submount(server, path->dentry, fh, fattr);
if (IS_ERR(mnt))
goto out;
@@ -158,15 +170,38 @@ out:
nfs_free_fattr(fattr);
nfs_free_fhandle(fh);
out_nofree:
- dprintk("<-- nfs_follow_mountpoint() = %p\n", mnt);
+ if (IS_ERR(mnt))
+ dprintk("<-- %s(): error %ld\n", __func__, PTR_ERR(mnt));
+ else
+ dprintk("<-- %s() = %p\n", __func__, mnt);
return mnt;
}
+static int
+nfs_namespace_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
+{
+ if (NFS_FH(dentry->d_inode)->size != 0)
+ return nfs_getattr(mnt, dentry, stat);
+ generic_fillattr(dentry->d_inode, stat);
+ return 0;
+}
+
+static int
+nfs_namespace_setattr(struct dentry *dentry, struct iattr *attr)
+{
+ if (NFS_FH(dentry->d_inode)->size != 0)
+ return nfs_setattr(dentry, attr);
+ return -EACCES;
+}
+
const struct inode_operations nfs_mountpoint_inode_operations = {
.getattr = nfs_getattr,
+ .setattr = nfs_setattr,
};
const struct inode_operations nfs_referral_inode_operations = {
+ .getattr = nfs_namespace_getattr,
+ .setattr = nfs_namespace_setattr,
};
static void nfs_expire_automounts(struct work_struct *work)
@@ -191,40 +226,26 @@ static struct vfsmount *nfs_do_clone_mount(struct nfs_server *server,
const char *devname,
struct nfs_clone_mount *mountdata)
{
-#ifdef CONFIG_NFS_V4
- struct vfsmount *mnt = ERR_PTR(-EINVAL);
- switch (server->nfs_client->rpc_ops->version) {
- case 2:
- case 3:
- mnt = vfs_kern_mount(&nfs_xdev_fs_type, 0, devname, mountdata);
- break;
- case 4:
- mnt = vfs_kern_mount(&nfs4_xdev_fs_type, 0, devname, mountdata);
- }
- return mnt;
-#else
return vfs_kern_mount(&nfs_xdev_fs_type, 0, devname, mountdata);
-#endif
}
/**
* nfs_do_submount - set up mountpoint when crossing a filesystem boundary
- * @mnt_parent - mountpoint of parent directory
* @dentry - parent directory
* @fh - filehandle for new root dentry
* @fattr - attributes for new root inode
+ * @authflavor - security flavor to use when performing the mount
*
*/
-static struct vfsmount *nfs_do_submount(const struct vfsmount *mnt_parent,
- const struct dentry *dentry,
- struct nfs_fh *fh,
- struct nfs_fattr *fattr)
+struct vfsmount *nfs_do_submount(struct dentry *dentry, struct nfs_fh *fh,
+ struct nfs_fattr *fattr, rpc_authflavor_t authflavor)
{
struct nfs_clone_mount mountdata = {
- .sb = mnt_parent->mnt_sb,
+ .sb = dentry->d_sb,
.dentry = dentry,
.fh = fh,
.fattr = fattr,
+ .authflavor = authflavor,
};
struct vfsmount *mnt = ERR_PTR(-ENOMEM);
char *page = (char *) __get_free_page(GFP_USER);
@@ -232,16 +253,15 @@ static struct vfsmount *nfs_do_submount(const struct vfsmount *mnt_parent,
dprintk("--> nfs_do_submount()\n");
- dprintk("%s: submounting on %s/%s\n", __func__,
- dentry->d_parent->d_name.name,
- dentry->d_name.name);
+ dprintk("%s: submounting on %pd2\n", __func__,
+ dentry);
if (page == NULL)
goto out;
- devname = nfs_devname(mnt_parent, dentry, page, PAGE_SIZE);
+ devname = nfs_devname(dentry, page, PAGE_SIZE);
mnt = (struct vfsmount *)devname;
if (IS_ERR(devname))
goto free_page;
- mnt = nfs_do_clone_mount(NFS_SB(mnt_parent->mnt_sb), devname, &mountdata);
+ mnt = nfs_do_clone_mount(NFS_SB(dentry->d_sb), devname, &mountdata);
free_page:
free_page((unsigned long)page);
out:
@@ -250,3 +270,20 @@ out:
dprintk("<-- nfs_do_submount() = %p\n", mnt);
return mnt;
}
+EXPORT_SYMBOL_GPL(nfs_do_submount);
+
+struct vfsmount *nfs_submount(struct nfs_server *server, struct dentry *dentry,
+ struct nfs_fh *fh, struct nfs_fattr *fattr)
+{
+ int err;
+ struct dentry *parent = dget_parent(dentry);
+
+ /* Look it up again to get its attributes */
+ err = server->nfs_client->rpc_ops->lookup(parent->d_inode, &dentry->d_name, fh, fattr, NULL);
+ dput(parent);
+ if (err != 0)
+ return ERR_PTR(err);
+
+ return nfs_do_submount(dentry, fh, fattr, server->client->cl_auth->au_flavor);
+}
+EXPORT_SYMBOL_GPL(nfs_submount);