diff options
Diffstat (limited to 'fs/nfs/namespace.c')
| -rw-r--r-- | fs/nfs/namespace.c | 167 |
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); |
