forked from Minki/linux
nfs: make nfs_path() work without vfsmount
part 3: now we have everything to get nfs_path() just by dentry - just follow to (disconnected) root and pick the rest of the thing there. Start killing propagation of struct vfsmount * on the paths that used to bring it to nfs_path(). Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Al Viro
parent
b1942c5f8c
commit
b514f872f8
@ -163,10 +163,10 @@ static inline void nfs_fs_proc_exit(void)
|
||||
|
||||
/* nfs4namespace.c */
|
||||
#ifdef CONFIG_NFS_V4
|
||||
extern struct vfsmount *nfs_do_refmount(const struct vfsmount *mnt_parent, struct dentry *dentry);
|
||||
extern struct vfsmount *nfs_do_refmount(struct super_block *sb, struct dentry *dentry);
|
||||
#else
|
||||
static inline
|
||||
struct vfsmount *nfs_do_refmount(const struct vfsmount *mnt_parent, struct dentry *dentry)
|
||||
struct vfsmount *nfs_do_refmount(struct super_block *sb, struct dentry *dentry)
|
||||
{
|
||||
return ERR_PTR(-ENOENT);
|
||||
}
|
||||
@ -247,9 +247,7 @@ extern void nfs_sb_active(struct super_block *sb);
|
||||
extern void nfs_sb_deactive(struct super_block *sb);
|
||||
|
||||
/* namespace.c */
|
||||
extern char *nfs_path(const char *base,
|
||||
const struct dentry *droot,
|
||||
const struct dentry *dentry,
|
||||
extern char *nfs_path(char **p, struct dentry *dentry,
|
||||
char *buffer, ssize_t buflen);
|
||||
extern struct vfsmount *nfs_d_automount(struct path *path);
|
||||
|
||||
@ -290,12 +288,11 @@ extern int _nfs4_call_sync_session(struct nfs_server *server,
|
||||
/*
|
||||
* Determine the device name as a string
|
||||
*/
|
||||
static inline char *nfs_devname(const struct vfsmount *mnt_parent,
|
||||
const struct dentry *dentry,
|
||||
static inline char *nfs_devname(struct dentry *dentry,
|
||||
char *buffer, ssize_t buflen)
|
||||
{
|
||||
return nfs_path(mnt_parent->mnt_devname, mnt_parent->mnt_root,
|
||||
dentry, buffer, buflen);
|
||||
char *dummy;
|
||||
return nfs_path(&dummy, dentry, buffer, buflen);
|
||||
}
|
||||
|
||||
/*
|
||||
|
||||
@ -25,33 +25,31 @@ 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,
|
||||
static struct vfsmount *nfs_do_submount(struct super_block *sb,
|
||||
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
|
||||
*
|
||||
* 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.
|
||||
*/
|
||||
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)
|
||||
{
|
||||
char *end;
|
||||
int namelen;
|
||||
unsigned seq;
|
||||
const char *base;
|
||||
|
||||
rename_retry:
|
||||
end = buffer+buflen;
|
||||
@ -60,7 +58,10 @@ 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)
|
||||
@ -68,27 +69,47 @@ 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 (--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--;
|
||||
buflen -= namelen;
|
||||
if (buflen < 0)
|
||||
if (buflen < 0) {
|
||||
spin_lock(&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_lock(&dentry->d_lock);
|
||||
rcu_read_unlock();
|
||||
if (read_seqretry(&rename_lock, seq))
|
||||
goto rename_retry;
|
||||
@ -143,9 +164,9 @@ struct vfsmount *nfs_d_automount(struct path *path)
|
||||
}
|
||||
|
||||
if (fattr->valid & NFS_ATTR_FATTR_V4_REFERRAL)
|
||||
mnt = nfs_do_refmount(path->mnt, path->dentry);
|
||||
mnt = nfs_do_refmount(path->mnt->mnt_sb, path->dentry);
|
||||
else
|
||||
mnt = nfs_do_submount(path->mnt, path->dentry, fh, fattr);
|
||||
mnt = nfs_do_submount(path->mnt->mnt_sb, path->dentry, fh, fattr);
|
||||
if (IS_ERR(mnt))
|
||||
goto out;
|
||||
|
||||
@ -209,19 +230,19 @@ static struct vfsmount *nfs_do_clone_mount(struct nfs_server *server,
|
||||
|
||||
/**
|
||||
* nfs_do_submount - set up mountpoint when crossing a filesystem boundary
|
||||
* @mnt_parent - mountpoint of parent directory
|
||||
* @sb - superblock of parent directory
|
||||
* @dentry - parent directory
|
||||
* @fh - filehandle for new root dentry
|
||||
* @fattr - attributes for new root inode
|
||||
*
|
||||
*/
|
||||
static struct vfsmount *nfs_do_submount(const struct vfsmount *mnt_parent,
|
||||
const struct dentry *dentry,
|
||||
static struct vfsmount *nfs_do_submount(struct super_block *sb,
|
||||
struct dentry *dentry,
|
||||
struct nfs_fh *fh,
|
||||
struct nfs_fattr *fattr)
|
||||
{
|
||||
struct nfs_clone_mount mountdata = {
|
||||
.sb = mnt_parent->mnt_sb,
|
||||
.sb = sb,
|
||||
.dentry = dentry,
|
||||
.fh = fh,
|
||||
.fattr = fattr,
|
||||
@ -237,11 +258,11 @@ static struct vfsmount *nfs_do_submount(const struct vfsmount *mnt_parent,
|
||||
dentry->d_name.name);
|
||||
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(sb), devname, &mountdata);
|
||||
free_page:
|
||||
free_page((unsigned long)page);
|
||||
out:
|
||||
|
||||
@ -54,33 +54,29 @@ Elong:
|
||||
/*
|
||||
* Determine the mount path as a string
|
||||
*/
|
||||
static char *nfs4_path(const struct vfsmount *mnt_parent,
|
||||
const struct dentry *dentry,
|
||||
char *buffer, ssize_t buflen)
|
||||
static char *nfs4_path(struct dentry *dentry, char *buffer, ssize_t buflen)
|
||||
{
|
||||
const char *srvpath;
|
||||
|
||||
srvpath = strchr(mnt_parent->mnt_devname, ':');
|
||||
if (srvpath)
|
||||
srvpath++;
|
||||
else
|
||||
srvpath = mnt_parent->mnt_devname;
|
||||
|
||||
return nfs_path(srvpath, mnt_parent->mnt_root, dentry, buffer, buflen);
|
||||
char *limit;
|
||||
char *path = nfs_path(&limit, dentry, buffer, buflen);
|
||||
if (!IS_ERR(path)) {
|
||||
char *colon = strchr(path, ':');
|
||||
if (colon && colon < limit)
|
||||
path = colon + 1;
|
||||
}
|
||||
return path;
|
||||
}
|
||||
|
||||
/*
|
||||
* Check that fs_locations::fs_root [RFC3530 6.3] is a prefix for what we
|
||||
* believe to be the server path to this dentry
|
||||
*/
|
||||
static int nfs4_validate_fspath(const struct vfsmount *mnt_parent,
|
||||
const struct dentry *dentry,
|
||||
static int nfs4_validate_fspath(struct dentry *dentry,
|
||||
const struct nfs4_fs_locations *locations,
|
||||
char *page, char *page2)
|
||||
{
|
||||
const char *path, *fs_path;
|
||||
|
||||
path = nfs4_path(mnt_parent, dentry, page, PAGE_SIZE);
|
||||
path = nfs4_path(dentry, page, PAGE_SIZE);
|
||||
if (IS_ERR(path))
|
||||
return PTR_ERR(path);
|
||||
|
||||
@ -165,20 +161,20 @@ static struct vfsmount *try_location(struct nfs_clone_mount *mountdata,
|
||||
|
||||
/**
|
||||
* nfs_follow_referral - set up mountpoint when hitting a referral on moved error
|
||||
* @mnt_parent - mountpoint of parent directory
|
||||
* @sb - superblock 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,
|
||||
static struct vfsmount *nfs_follow_referral(struct super_block *sb,
|
||||
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,
|
||||
.sb = sb,
|
||||
.dentry = dentry,
|
||||
.authflavor = NFS_SB(mnt_parent->mnt_sb)->client->cl_auth->au_flavor,
|
||||
.authflavor = NFS_SB(sb)->client->cl_auth->au_flavor,
|
||||
};
|
||||
char *page = NULL, *page2 = NULL;
|
||||
int loc, error;
|
||||
@ -198,7 +194,7 @@ static struct vfsmount *nfs_follow_referral(const struct vfsmount *mnt_parent,
|
||||
goto out;
|
||||
|
||||
/* Ensure fs path is a prefix of current dentry path */
|
||||
error = nfs4_validate_fspath(mnt_parent, dentry, locations, page, page2);
|
||||
error = nfs4_validate_fspath(dentry, locations, page, page2);
|
||||
if (error < 0) {
|
||||
mnt = ERR_PTR(error);
|
||||
goto out;
|
||||
@ -225,11 +221,10 @@ out:
|
||||
|
||||
/*
|
||||
* nfs_do_refmount - handle crossing a referral on server
|
||||
* @mnt_parent - mountpoint of referral
|
||||
* @dentry - dentry of referral
|
||||
*
|
||||
*/
|
||||
struct vfsmount *nfs_do_refmount(const struct vfsmount *mnt_parent, struct dentry *dentry)
|
||||
struct vfsmount *nfs_do_refmount(struct super_block *sb, struct dentry *dentry)
|
||||
{
|
||||
struct vfsmount *mnt = ERR_PTR(-ENOMEM);
|
||||
struct dentry *parent;
|
||||
@ -262,7 +257,7 @@ struct vfsmount *nfs_do_refmount(const struct vfsmount *mnt_parent, struct dentr
|
||||
fs_locations->fs_path.ncomponents <= 0)
|
||||
goto out_free;
|
||||
|
||||
mnt = nfs_follow_referral(mnt_parent, dentry, fs_locations);
|
||||
mnt = nfs_follow_referral(sb, dentry, fs_locations);
|
||||
out_free:
|
||||
__free_page(page);
|
||||
kfree(fs_locations);
|
||||
|
||||
@ -2771,16 +2771,15 @@ static struct vfsmount *nfs_do_root_mount(struct file_system_type *fs_type,
|
||||
return root_mnt;
|
||||
}
|
||||
|
||||
static void nfs_fix_devname(const struct path *path, struct vfsmount *mnt)
|
||||
static void nfs_fix_devname(struct dentry *dentry, struct vfsmount *mnt)
|
||||
{
|
||||
char *page = (char *) __get_free_page(GFP_KERNEL);
|
||||
char *devname, *tmp;
|
||||
char *dummy;
|
||||
|
||||
if (page == NULL)
|
||||
return;
|
||||
devname = nfs_path(path->mnt->mnt_devname,
|
||||
path->mnt->mnt_root, path->dentry,
|
||||
page, PAGE_SIZE);
|
||||
devname = nfs_path(&dummy, dentry, page, PAGE_SIZE);
|
||||
if (IS_ERR(devname))
|
||||
goto out_freepage;
|
||||
tmp = kstrdup(devname, GFP_KERNEL);
|
||||
@ -2894,7 +2893,7 @@ static int nfs_follow_remote_path(struct vfsmount *root_mnt,
|
||||
mnt_target->mnt_root = dget(nd->path.dentry);
|
||||
|
||||
/* Correct the device pathname */
|
||||
nfs_fix_devname(&nd->path, mnt_target);
|
||||
nfs_fix_devname(nd->path.dentry, mnt_target);
|
||||
|
||||
path_put(&nd->path);
|
||||
kfree(nd);
|
||||
|
||||
Loading…
Reference in New Issue
Block a user