/**
* nfs_follow_referral - set up mountpoint when hitting a referral on moved error
* @mnt_parent - mountpoint of parent directory
* @dentry - parent directory
* @locations - array of NFSv4 server location information
*
*/
static struct vfsmount *nfs_follow_referral(const struct vfsmount *mnt_parent,
const struct dentry *dentry,
const struct nfs4_fs_locations *locations)
{
struct vfsmount *mnt = ERR_PTR(-ENOENT);
struct nfs_clone_mount mountdata = {
.sb = mnt_parent->mnt_sb,
.dentry = dentry,
.authflavor = NFS_SB(mnt_parent->mnt_sb)->client->cl_auth->au_flavor,
};
char *page = NULL, *page2 = NULL;
unsigned int s;
int loc, error;
if (locations == NULL || locations->nlocations <= 0)
goto out;
dprintk("%s: referral at %s/%s\n", __func__,
dentry->d_parent->d_name.name, dentry->d_name.name);
page = (char *) __get_free_page(GFP_USER);
if (!page)
goto out;
page2 = (char *) __get_free_page(GFP_USER);
if (!page2)
goto out;
/* Ensure fs path is a prefix of current dentry path */
error = nfs4_validate_fspath(mnt_parent, dentry, locations, page, page2);
if (error < 0) {
mnt = ERR_PTR(error);
goto out;
}
loc = 0;
while (loc < locations->nlocations && IS_ERR(mnt)) {
const struct nfs4_fs_location *location = &locations->locations[loc];
char *mnt_path;
if (location == NULL || location->nservers <= 0 ||
location->rootpath.ncomponents == 0) {
loc++;
continue;
}
mnt_path = nfs4_pathname_string(&location->rootpath, page2, PAGE_SIZE);
if (IS_ERR(mnt_path)) {
loc++;
continue;
}
mountdata.mnt_path = mnt_path;
s = 0;
while (s < location->nservers) {
struct sockaddr_in addr = {
.sin_family = AF_INET,
.sin_port = htons(NFS_PORT),
};
if (location->servers[s].len <= 0 ||
valid_ipaddr4(location->servers[s].data) < 0) {
s++;
continue;
}
mountdata.hostname = location->servers[s].data;
addr.sin_addr.s_addr = in_aton(mountdata.hostname),
mountdata.addr = (struct sockaddr *)&addr;
mountdata.addrlen = sizeof(addr);
snprintf(page, PAGE_SIZE, "%s:%s",
mountdata.hostname,
mountdata.mnt_path);
mnt = vfs_kern_mount(&nfs4_referral_fs_type, 0, page, &mountdata);
if (!IS_ERR(mnt)) {
break;
}
s++;
}
loc++;
}
out:
free_page((unsigned long) page);
free_page((unsigned long) page2);
dprintk("%s: done\n", __func__);
return mnt;
}
/*
* nfs_do_refmount - handle crossing a referral on server
* @dentry - dentry of referral
* @nd - nameidata info
*
*/
struct vfsmount *nfs_do_refmount(const struct vfsmount *mnt_parent, struct dentry *dentry)
{
struct vfsmount *mnt = ERR_PTR(-ENOMEM);
struct dentry *parent;
struct nfs4_fs_locations *fs_locations = NULL;
struct page *page;
int err;
/* BUG_ON(IS_ROOT(dentry)); */
dprintk("%s: enter\n", __func__);
page = alloc_page(GFP_KERNEL);
if (page == NULL)
goto out;
fs_locations = kmalloc(sizeof(struct nfs4_fs_locations), GFP_KERNEL);
if (fs_locations == NULL)
goto out_free;
/* Get locations */
mnt = ERR_PTR(-ENOENT);
parent = dget_parent(dentry);
dprintk("%s: getting locations for %s/%s\n",
__func__, parent->d_name.name, dentry->d_name.name);
err = nfs4_proc_fs_locations(parent->d_inode, &dentry->d_name, fs_locations, page);
dput(parent);
if (err != 0 ||
fs_locations->nlocations <= 0 ||
fs_locations->fs_path.ncomponents <= 0)
goto out_free;
mnt = nfs_follow_referral(mnt_parent, dentry, fs_locations);
out_free:
__free_page(page);
kfree(fs_locations);
out:
dprintk("%s: done\n", __func__);
return mnt;
}
/**
* nfs_follow_referral - set up mountpoint when hitting a referral on moved error
* @dentry - parent directory
* @locations - array of NFSv4 server location information
*
*/
static struct vfsmount *nfs_follow_referral(struct dentry *dentry,
const struct nfs4_fs_locations *locations)
{
struct vfsmount *mnt = ERR_PTR(-ENOENT);
struct nfs_clone_mount mountdata = {
.sb = dentry->d_sb,
.dentry = dentry,
.authflavor = NFS_SB(dentry->d_sb)->client->cl_auth->au_flavor,
};
char *page = NULL, *page2 = NULL;
int loc, error;
if (locations == NULL || locations->nlocations <= 0)
goto out;
dprintk("%s: referral at %s/%s\n", __func__,
dentry->d_parent->d_name.name, dentry->d_name.name);
page = (char *) __get_free_page(GFP_USER);
if (!page)
goto out;
page2 = (char *) __get_free_page(GFP_USER);
if (!page2)
goto out;
/* Ensure fs path is a prefix of current dentry path */
error = nfs4_validate_fspath(dentry, locations, page, page2);
if (error < 0) {
mnt = ERR_PTR(error);
goto out;
}
for (loc = 0; loc < locations->nlocations; loc++) {
const struct nfs4_fs_location *location = &locations->locations[loc];
if (location == NULL || location->nservers <= 0 ||
location->rootpath.ncomponents == 0)
continue;
mnt = try_location(&mountdata, page, page2, location);
if (!IS_ERR(mnt))
break;
}
out:
free_page((unsigned long) page);
free_page((unsigned long) page2);
dprintk("%s: done\n", __func__);
return mnt;
}
/*
* nfs_do_refmount - handle crossing a referral on server
* @dentry - dentry of referral
*
*/
struct vfsmount *nfs_do_refmount(struct dentry *dentry)
{
struct vfsmount *mnt = ERR_PTR(-ENOMEM);
struct dentry *parent;
struct nfs4_fs_locations *fs_locations = NULL;
struct page *page;
int err;
/* BUG_ON(IS_ROOT(dentry)); */
dprintk("%s: enter\n", __func__);
page = alloc_page(GFP_KERNEL);
if (page == NULL)
goto out;
fs_locations = kmalloc(sizeof(struct nfs4_fs_locations), GFP_KERNEL);
if (fs_locations == NULL)
goto out_free;
/* Get locations */
mnt = ERR_PTR(-ENOENT);
parent = dget_parent(dentry);
dprintk("%s: getting locations for %s/%s\n",
__func__, parent->d_name.name, dentry->d_name.name);
err = nfs4_proc_fs_locations(parent->d_inode, &dentry->d_name, fs_locations, page);
dput(parent);
if (err != 0 ||
fs_locations->nlocations <= 0 ||
fs_locations->fs_path.ncomponents <= 0)
goto out_free;
mnt = nfs_follow_referral(dentry, fs_locations);
out_free:
__free_page(page);
kfree(fs_locations);
out:
dprintk("%s: done\n", __func__);
return mnt;
}
