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-rw-r--r--fs/nfs/super.c1074
1 files changed, 1074 insertions, 0 deletions
diff --git a/fs/nfs/super.c b/fs/nfs/super.c
new file mode 100644
index 00000000000..e8d40030cab
--- /dev/null
+++ b/fs/nfs/super.c
@@ -0,0 +1,1074 @@
+/*
+ * linux/fs/nfs/super.c
+ *
+ * Copyright (C) 1992 Rick Sladkey
+ *
+ * nfs superblock handling functions
+ *
+ * Modularised by Alan Cox <Alan.Cox@linux.org>, while hacking some
+ * experimental NFS changes. Modularisation taken straight from SYS5 fs.
+ *
+ * Change to nfs_read_super() to permit NFS mounts to multi-homed hosts.
+ * J.S.Peatfield@damtp.cam.ac.uk
+ *
+ * Split from inode.c by David Howells <dhowells@redhat.com>
+ *
+ * - superblocks are indexed on server only - all inodes, dentries, etc. associated with a
+ * particular server are held in the same superblock
+ * - NFS superblocks can have several effective roots to the dentry tree
+ * - directory type roots are spliced into the tree when a path from one root reaches the root
+ * of another (see nfs_lookup())
+ */
+
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/init.h>
+
+#include <linux/time.h>
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/string.h>
+#include <linux/stat.h>
+#include <linux/errno.h>
+#include <linux/unistd.h>
+#include <linux/sunrpc/clnt.h>
+#include <linux/sunrpc/stats.h>
+#include <linux/sunrpc/metrics.h>
+#include <linux/nfs_fs.h>
+#include <linux/nfs_mount.h>
+#include <linux/nfs4_mount.h>
+#include <linux/lockd/bind.h>
+#include <linux/smp_lock.h>
+#include <linux/seq_file.h>
+#include <linux/mount.h>
+#include <linux/nfs_idmap.h>
+#include <linux/vfs.h>
+#include <linux/inet.h>
+#include <linux/nfs_xdr.h>
+
+#include <asm/system.h>
+#include <asm/uaccess.h>
+
+#include "nfs4_fs.h"
+#include "callback.h"
+#include "delegation.h"
+#include "iostat.h"
+#include "internal.h"
+
+#define NFSDBG_FACILITY NFSDBG_VFS
+
+static void nfs_umount_begin(struct vfsmount *, int);
+static int nfs_statfs(struct dentry *, struct kstatfs *);
+static int nfs_show_options(struct seq_file *, struct vfsmount *);
+static int nfs_show_stats(struct seq_file *, struct vfsmount *);
+static int nfs_get_sb(struct file_system_type *, int, const char *, void *, struct vfsmount *);
+static int nfs_xdev_get_sb(struct file_system_type *fs_type,
+ int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
+static void nfs_kill_super(struct super_block *);
+
+static struct file_system_type nfs_fs_type = {
+ .owner = THIS_MODULE,
+ .name = "nfs",
+ .get_sb = nfs_get_sb,
+ .kill_sb = nfs_kill_super,
+ .fs_flags = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
+};
+
+struct file_system_type nfs_xdev_fs_type = {
+ .owner = THIS_MODULE,
+ .name = "nfs",
+ .get_sb = nfs_xdev_get_sb,
+ .kill_sb = nfs_kill_super,
+ .fs_flags = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
+};
+
+static struct super_operations nfs_sops = {
+ .alloc_inode = nfs_alloc_inode,
+ .destroy_inode = nfs_destroy_inode,
+ .write_inode = nfs_write_inode,
+ .statfs = nfs_statfs,
+ .clear_inode = nfs_clear_inode,
+ .umount_begin = nfs_umount_begin,
+ .show_options = nfs_show_options,
+ .show_stats = nfs_show_stats,
+};
+
+#ifdef CONFIG_NFS_V4
+static int nfs4_get_sb(struct file_system_type *fs_type,
+ int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
+static int nfs4_xdev_get_sb(struct file_system_type *fs_type,
+ int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
+static int nfs4_referral_get_sb(struct file_system_type *fs_type,
+ int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
+static void nfs4_kill_super(struct super_block *sb);
+
+static struct file_system_type nfs4_fs_type = {
+ .owner = THIS_MODULE,
+ .name = "nfs4",
+ .get_sb = nfs4_get_sb,
+ .kill_sb = nfs4_kill_super,
+ .fs_flags = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
+};
+
+struct file_system_type nfs4_xdev_fs_type = {
+ .owner = THIS_MODULE,
+ .name = "nfs4",
+ .get_sb = nfs4_xdev_get_sb,
+ .kill_sb = nfs4_kill_super,
+ .fs_flags = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
+};
+
+struct file_system_type nfs4_referral_fs_type = {
+ .owner = THIS_MODULE,
+ .name = "nfs4",
+ .get_sb = nfs4_referral_get_sb,
+ .kill_sb = nfs4_kill_super,
+ .fs_flags = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
+};
+
+static struct super_operations nfs4_sops = {
+ .alloc_inode = nfs_alloc_inode,
+ .destroy_inode = nfs_destroy_inode,
+ .write_inode = nfs_write_inode,
+ .statfs = nfs_statfs,
+ .clear_inode = nfs4_clear_inode,
+ .umount_begin = nfs_umount_begin,
+ .show_options = nfs_show_options,
+ .show_stats = nfs_show_stats,
+};
+#endif
+
+static struct shrinker *acl_shrinker;
+
+/*
+ * Register the NFS filesystems
+ */
+int __init register_nfs_fs(void)
+{
+ int ret;
+
+ ret = register_filesystem(&nfs_fs_type);
+ if (ret < 0)
+ goto error_0;
+
+#ifdef CONFIG_NFS_V4
+ ret = nfs_register_sysctl();
+ if (ret < 0)
+ goto error_1;
+ ret = register_filesystem(&nfs4_fs_type);
+ if (ret < 0)
+ goto error_2;
+#endif
+ acl_shrinker = set_shrinker(DEFAULT_SEEKS, nfs_access_cache_shrinker);
+ return 0;
+
+#ifdef CONFIG_NFS_V4
+error_2:
+ nfs_unregister_sysctl();
+error_1:
+ unregister_filesystem(&nfs_fs_type);
+#endif
+error_0:
+ return ret;
+}
+
+/*
+ * Unregister the NFS filesystems
+ */
+void __exit unregister_nfs_fs(void)
+{
+ if (acl_shrinker != NULL)
+ remove_shrinker(acl_shrinker);
+#ifdef CONFIG_NFS_V4
+ unregister_filesystem(&nfs4_fs_type);
+ nfs_unregister_sysctl();
+#endif
+ unregister_filesystem(&nfs_fs_type);
+}
+
+/*
+ * Deliver file system statistics to userspace
+ */
+static int nfs_statfs(struct dentry *dentry, struct kstatfs *buf)
+{
+ struct nfs_server *server = NFS_SB(dentry->d_sb);
+ unsigned char blockbits;
+ unsigned long blockres;
+ struct nfs_fh *fh = NFS_FH(dentry->d_inode);
+ struct nfs_fattr fattr;
+ struct nfs_fsstat res = {
+ .fattr = &fattr,
+ };
+ int error;
+
+ lock_kernel();
+
+ error = server->nfs_client->rpc_ops->statfs(server, fh, &res);
+ buf->f_type = NFS_SUPER_MAGIC;
+ if (error < 0)
+ goto out_err;
+
+ /*
+ * Current versions of glibc do not correctly handle the
+ * case where f_frsize != f_bsize. Eventually we want to
+ * report the value of wtmult in this field.
+ */
+ buf->f_frsize = dentry->d_sb->s_blocksize;
+
+ /*
+ * On most *nix systems, f_blocks, f_bfree, and f_bavail
+ * are reported in units of f_frsize. Linux hasn't had
+ * an f_frsize field in its statfs struct until recently,
+ * thus historically Linux's sys_statfs reports these
+ * fields in units of f_bsize.
+ */
+ buf->f_bsize = dentry->d_sb->s_blocksize;
+ blockbits = dentry->d_sb->s_blocksize_bits;
+ blockres = (1 << blockbits) - 1;
+ buf->f_blocks = (res.tbytes + blockres) >> blockbits;
+ buf->f_bfree = (res.fbytes + blockres) >> blockbits;
+ buf->f_bavail = (res.abytes + blockres) >> blockbits;
+
+ buf->f_files = res.tfiles;
+ buf->f_ffree = res.afiles;
+
+ buf->f_namelen = server->namelen;
+ out:
+ unlock_kernel();
+ return 0;
+
+ out_err:
+ dprintk("%s: statfs error = %d\n", __FUNCTION__, -error);
+ buf->f_bsize = buf->f_blocks = buf->f_bfree = buf->f_bavail = -1;
+ goto out;
+
+}
+
+/*
+ * Map the security flavour number to a name
+ */
+static const char *nfs_pseudoflavour_to_name(rpc_authflavor_t flavour)
+{
+ static const struct {
+ rpc_authflavor_t flavour;
+ const char *str;
+ } sec_flavours[] = {
+ { RPC_AUTH_NULL, "null" },
+ { RPC_AUTH_UNIX, "sys" },
+ { RPC_AUTH_GSS_KRB5, "krb5" },
+ { RPC_AUTH_GSS_KRB5I, "krb5i" },
+ { RPC_AUTH_GSS_KRB5P, "krb5p" },
+ { RPC_AUTH_GSS_LKEY, "lkey" },
+ { RPC_AUTH_GSS_LKEYI, "lkeyi" },
+ { RPC_AUTH_GSS_LKEYP, "lkeyp" },
+ { RPC_AUTH_GSS_SPKM, "spkm" },
+ { RPC_AUTH_GSS_SPKMI, "spkmi" },
+ { RPC_AUTH_GSS_SPKMP, "spkmp" },
+ { -1, "unknown" }
+ };
+ int i;
+
+ for (i=0; sec_flavours[i].flavour != -1; i++) {
+ if (sec_flavours[i].flavour == flavour)
+ break;
+ }
+ return sec_flavours[i].str;
+}
+
+/*
+ * Describe the mount options in force on this server representation
+ */
+static void nfs_show_mount_options(struct seq_file *m, struct nfs_server *nfss, int showdefaults)
+{
+ static const struct proc_nfs_info {
+ int flag;
+ const char *str;
+ const char *nostr;
+ } nfs_info[] = {
+ { NFS_MOUNT_SOFT, ",soft", ",hard" },
+ { NFS_MOUNT_INTR, ",intr", "" },
+ { NFS_MOUNT_NOCTO, ",nocto", "" },
+ { NFS_MOUNT_NOAC, ",noac", "" },
+ { NFS_MOUNT_NONLM, ",nolock", "" },
+ { NFS_MOUNT_NOACL, ",noacl", "" },
+ { 0, NULL, NULL }
+ };
+ const struct proc_nfs_info *nfs_infop;
+ struct nfs_client *clp = nfss->nfs_client;
+ char buf[12];
+ const char *proto;
+
+ seq_printf(m, ",vers=%d", clp->rpc_ops->version);
+ seq_printf(m, ",rsize=%d", nfss->rsize);
+ seq_printf(m, ",wsize=%d", nfss->wsize);
+ if (nfss->acregmin != 3*HZ || showdefaults)
+ seq_printf(m, ",acregmin=%d", nfss->acregmin/HZ);
+ if (nfss->acregmax != 60*HZ || showdefaults)
+ seq_printf(m, ",acregmax=%d", nfss->acregmax/HZ);
+ if (nfss->acdirmin != 30*HZ || showdefaults)
+ seq_printf(m, ",acdirmin=%d", nfss->acdirmin/HZ);
+ if (nfss->acdirmax != 60*HZ || showdefaults)
+ seq_printf(m, ",acdirmax=%d", nfss->acdirmax/HZ);
+ for (nfs_infop = nfs_info; nfs_infop->flag; nfs_infop++) {
+ if (nfss->flags & nfs_infop->flag)
+ seq_puts(m, nfs_infop->str);
+ else
+ seq_puts(m, nfs_infop->nostr);
+ }
+ switch (nfss->client->cl_xprt->prot) {
+ case IPPROTO_TCP:
+ proto = "tcp";
+ break;
+ case IPPROTO_UDP:
+ proto = "udp";
+ break;
+ default:
+ snprintf(buf, sizeof(buf), "%u", nfss->client->cl_xprt->prot);
+ proto = buf;
+ }
+ seq_printf(m, ",proto=%s", proto);
+ seq_printf(m, ",timeo=%lu", 10U * clp->retrans_timeo / HZ);
+ seq_printf(m, ",retrans=%u", clp->retrans_count);
+ seq_printf(m, ",sec=%s", nfs_pseudoflavour_to_name(nfss->client->cl_auth->au_flavor));
+}
+
+/*
+ * Describe the mount options on this VFS mountpoint
+ */
+static int nfs_show_options(struct seq_file *m, struct vfsmount *mnt)
+{
+ struct nfs_server *nfss = NFS_SB(mnt->mnt_sb);
+
+ nfs_show_mount_options(m, nfss, 0);
+
+ seq_puts(m, ",addr=");
+ seq_escape(m, nfss->nfs_client->cl_hostname, " \t\n\\");
+
+ return 0;
+}
+
+/*
+ * Present statistical information for this VFS mountpoint
+ */
+static int nfs_show_stats(struct seq_file *m, struct vfsmount *mnt)
+{
+ int i, cpu;
+ struct nfs_server *nfss = NFS_SB(mnt->mnt_sb);
+ struct rpc_auth *auth = nfss->client->cl_auth;
+ struct nfs_iostats totals = { };
+
+ seq_printf(m, "statvers=%s", NFS_IOSTAT_VERS);
+
+ /*
+ * Display all mount option settings
+ */
+ seq_printf(m, "\n\topts:\t");
+ seq_puts(m, mnt->mnt_sb->s_flags & MS_RDONLY ? "ro" : "rw");
+ seq_puts(m, mnt->mnt_sb->s_flags & MS_SYNCHRONOUS ? ",sync" : "");
+ seq_puts(m, mnt->mnt_sb->s_flags & MS_NOATIME ? ",noatime" : "");
+ seq_puts(m, mnt->mnt_sb->s_flags & MS_NODIRATIME ? ",nodiratime" : "");
+ nfs_show_mount_options(m, nfss, 1);
+
+ seq_printf(m, "\n\tage:\t%lu", (jiffies - nfss->mount_time) / HZ);
+
+ seq_printf(m, "\n\tcaps:\t");
+ seq_printf(m, "caps=0x%x", nfss->caps);
+ seq_printf(m, ",wtmult=%d", nfss->wtmult);
+ seq_printf(m, ",dtsize=%d", nfss->dtsize);
+ seq_printf(m, ",bsize=%d", nfss->bsize);
+ seq_printf(m, ",namelen=%d", nfss->namelen);
+
+#ifdef CONFIG_NFS_V4
+ if (nfss->nfs_client->cl_nfsversion == 4) {
+ seq_printf(m, "\n\tnfsv4:\t");
+ seq_printf(m, "bm0=0x%x", nfss->attr_bitmask[0]);
+ seq_printf(m, ",bm1=0x%x", nfss->attr_bitmask[1]);
+ seq_printf(m, ",acl=0x%x", nfss->acl_bitmask);
+ }
+#endif
+
+ /*
+ * Display security flavor in effect for this mount
+ */
+ seq_printf(m, "\n\tsec:\tflavor=%d", auth->au_ops->au_flavor);
+ if (auth->au_flavor)
+ seq_printf(m, ",pseudoflavor=%d", auth->au_flavor);
+
+ /*
+ * Display superblock I/O counters
+ */
+ for_each_possible_cpu(cpu) {
+ struct nfs_iostats *stats;
+
+ preempt_disable();
+ stats = per_cpu_ptr(nfss->io_stats, cpu);
+
+ for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
+ totals.events[i] += stats->events[i];
+ for (i = 0; i < __NFSIOS_BYTESMAX; i++)
+ totals.bytes[i] += stats->bytes[i];
+
+ preempt_enable();
+ }
+
+ seq_printf(m, "\n\tevents:\t");
+ for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
+ seq_printf(m, "%lu ", totals.events[i]);
+ seq_printf(m, "\n\tbytes:\t");
+ for (i = 0; i < __NFSIOS_BYTESMAX; i++)
+ seq_printf(m, "%Lu ", totals.bytes[i]);
+ seq_printf(m, "\n");
+
+ rpc_print_iostats(m, nfss->client);
+
+ return 0;
+}
+
+/*
+ * Begin unmount by attempting to remove all automounted mountpoints we added
+ * in response to xdev traversals and referrals
+ */
+static void nfs_umount_begin(struct vfsmount *vfsmnt, int flags)
+{
+ shrink_submounts(vfsmnt, &nfs_automount_list);
+}
+
+/*
+ * Validate the NFS2/NFS3 mount data
+ * - fills in the mount root filehandle
+ */
+static int nfs_validate_mount_data(struct nfs_mount_data *data,
+ struct nfs_fh *mntfh)
+{
+ if (data == NULL) {
+ dprintk("%s: missing data argument\n", __FUNCTION__);
+ return -EINVAL;
+ }
+
+ if (data->version <= 0 || data->version > NFS_MOUNT_VERSION) {
+ dprintk("%s: bad mount version\n", __FUNCTION__);
+ return -EINVAL;
+ }
+
+ switch (data->version) {
+ case 1:
+ data->namlen = 0;
+ case 2:
+ data->bsize = 0;
+ case 3:
+ if (data->flags & NFS_MOUNT_VER3) {
+ dprintk("%s: mount structure version %d does not support NFSv3\n",
+ __FUNCTION__,
+ data->version);
+ return -EINVAL;
+ }
+ data->root.size = NFS2_FHSIZE;
+ memcpy(data->root.data, data->old_root.data, NFS2_FHSIZE);
+ case 4:
+ if (data->flags & NFS_MOUNT_SECFLAVOUR) {
+ dprintk("%s: mount structure version %d does not support strong security\n",
+ __FUNCTION__,
+ data->version);
+ return -EINVAL;
+ }
+ case 5:
+ memset(data->context, 0, sizeof(data->context));
+ }
+
+ /* Set the pseudoflavor */
+ if (!(data->flags & NFS_MOUNT_SECFLAVOUR))
+ data->pseudoflavor = RPC_AUTH_UNIX;
+
+#ifndef CONFIG_NFS_V3
+ /* If NFSv3 is not compiled in, return -EPROTONOSUPPORT */
+ if (data->flags & NFS_MOUNT_VER3) {
+ dprintk("%s: NFSv3 not compiled into kernel\n", __FUNCTION__);
+ return -EPROTONOSUPPORT;
+ }
+#endif /* CONFIG_NFS_V3 */
+
+ /* We now require that the mount process passes the remote address */
+ if (data->addr.sin_addr.s_addr == INADDR_ANY) {
+ dprintk("%s: mount program didn't pass remote address!\n",
+ __FUNCTION__);
+ return -EINVAL;
+ }
+
+ /* Prepare the root filehandle */
+ if (data->flags & NFS_MOUNT_VER3)
+ mntfh->size = data->root.size;
+ else
+ mntfh->size = NFS2_FHSIZE;
+
+ if (mntfh->size > sizeof(mntfh->data)) {
+ dprintk("%s: invalid root filehandle\n", __FUNCTION__);
+ return -EINVAL;
+ }
+
+ memcpy(mntfh->data, data->root.data, mntfh->size);
+ if (mntfh->size < sizeof(mntfh->data))
+ memset(mntfh->data + mntfh->size, 0,
+ sizeof(mntfh->data) - mntfh->size);
+
+ return 0;
+}
+
+/*
+ * Initialise the common bits of the superblock
+ */
+static inline void nfs_initialise_sb(struct super_block *sb)
+{
+ struct nfs_server *server = NFS_SB(sb);
+
+ sb->s_magic = NFS_SUPER_MAGIC;
+
+ /* We probably want something more informative here */
+ snprintf(sb->s_id, sizeof(sb->s_id),
+ "%x:%x", MAJOR(sb->s_dev), MINOR(sb->s_dev));
+
+ if (sb->s_blocksize == 0)
+ sb->s_blocksize = nfs_block_bits(server->wsize,
+ &sb->s_blocksize_bits);
+
+ if (server->flags & NFS_MOUNT_NOAC)
+ sb->s_flags |= MS_SYNCHRONOUS;
+
+ nfs_super_set_maxbytes(sb, server->maxfilesize);
+}
+
+/*
+ * Finish setting up an NFS2/3 superblock
+ */
+static void nfs_fill_super(struct super_block *sb, struct nfs_mount_data *data)
+{
+ struct nfs_server *server = NFS_SB(sb);
+
+ sb->s_blocksize_bits = 0;
+ sb->s_blocksize = 0;
+ if (data->bsize)
+ sb->s_blocksize = nfs_block_size(data->bsize, &sb->s_blocksize_bits);
+
+ if (server->flags & NFS_MOUNT_VER3) {
+ /* The VFS shouldn't apply the umask to mode bits. We will do
+ * so ourselves when necessary.
+ */
+ sb->s_flags |= MS_POSIXACL;
+ sb->s_time_gran = 1;
+ }
+
+ sb->s_op = &nfs_sops;
+ nfs_initialise_sb(sb);
+}
+
+/*
+ * Finish setting up a cloned NFS2/3 superblock
+ */
+static void nfs_clone_super(struct super_block *sb,
+ const struct super_block *old_sb)
+{
+ struct nfs_server *server = NFS_SB(sb);
+
+ sb->s_blocksize_bits = old_sb->s_blocksize_bits;
+ sb->s_blocksize = old_sb->s_blocksize;
+ sb->s_maxbytes = old_sb->s_maxbytes;
+
+ if (server->flags & NFS_MOUNT_VER3) {
+ /* The VFS shouldn't apply the umask to mode bits. We will do
+ * so ourselves when necessary.
+ */
+ sb->s_flags |= MS_POSIXACL;
+ sb->s_time_gran = 1;
+ }
+
+ sb->s_op = old_sb->s_op;
+ nfs_initialise_sb(sb);
+}
+
+static int nfs_set_super(struct super_block *s, void *_server)
+{
+ struct nfs_server *server = _server;
+ int ret;
+
+ s->s_fs_info = server;
+ ret = set_anon_super(s, server);
+ if (ret == 0)
+ server->s_dev = s->s_dev;
+ return ret;
+}
+
+static int nfs_compare_super(struct super_block *sb, void *data)
+{
+ struct nfs_server *server = data, *old = NFS_SB(sb);
+
+ if (old->nfs_client != server->nfs_client)
+ return 0;
+ if (memcmp(&old->fsid, &server->fsid, sizeof(old->fsid)) != 0)
+ return 0;
+ return 1;
+}
+
+static int nfs_get_sb(struct file_system_type *fs_type,
+ int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt)
+{
+ struct nfs_server *server = NULL;
+ struct super_block *s;
+ struct nfs_fh mntfh;
+ struct nfs_mount_data *data = raw_data;
+ struct dentry *mntroot;
+ int error;
+
+ /* Validate the mount data */
+ error = nfs_validate_mount_data(data, &mntfh);
+ if (error < 0)
+ return error;
+
+ /* Get a volume representation */
+ server = nfs_create_server(data, &mntfh);
+ if (IS_ERR(server)) {
+ error = PTR_ERR(server);
+ goto out_err_noserver;
+ }
+
+ /* Get a superblock - note that we may end up sharing one that already exists */
+ s = sget(fs_type, nfs_compare_super, nfs_set_super, server);
+ if (IS_ERR(s)) {
+ error = PTR_ERR(s);
+ goto out_err_nosb;
+ }
+
+ if (s->s_fs_info != server) {
+ nfs_free_server(server);
+ server = NULL;
+ }
+
+ if (!s->s_root) {
+ /* initial superblock/root creation */
+ s->s_flags = flags;
+ nfs_fill_super(s, data);
+ }
+
+ mntroot = nfs_get_root(s, &mntfh);
+ if (IS_ERR(mntroot)) {
+ error = PTR_ERR(mntroot);
+ goto error_splat_super;
+ }
+
+ s->s_flags |= MS_ACTIVE;
+ mnt->mnt_sb = s;
+ mnt->mnt_root = mntroot;
+ return 0;
+
+out_err_nosb:
+ nfs_free_server(server);
+out_err_noserver:
+ return error;
+
+error_splat_super:
+ up_write(&s->s_umount);
+ deactivate_super(s);
+ return error;
+}
+
+/*
+ * Destroy an NFS2/3 superblock
+ */
+static void nfs_kill_super(struct super_block *s)
+{
+ struct nfs_server *server = NFS_SB(s);
+
+ kill_anon_super(s);
+ nfs_free_server(server);
+}
+
+/*
+ * Clone an NFS2/3 server record on xdev traversal (FSID-change)
+ */
+static int nfs_xdev_get_sb(struct file_system_type *fs_type, int flags,
+ const char *dev_name, void *raw_data,
+ struct vfsmount *mnt)
+{
+ struct nfs_clone_mount *data = raw_data;
+ struct super_block *s;
+ struct nfs_server *server;
+ struct dentry *mntroot;
+ int error;
+
+ dprintk("--> nfs_xdev_get_sb()\n");
+
+ /* create a new volume representation */
+ server = nfs_clone_server(NFS_SB(data->sb), data->fh, data->fattr);
+ if (IS_ERR(server)) {
+ error = PTR_ERR(server);
+ goto out_err_noserver;
+ }
+
+ /* Get a superblock - note that we may end up sharing one that already exists */
+ s = sget(&nfs_fs_type, nfs_compare_super, nfs_set_super, server);
+ if (IS_ERR(s)) {
+ error = PTR_ERR(s);
+ goto out_err_nosb;
+ }
+
+ if (s->s_fs_info != server) {
+ nfs_free_server(server);
+ server = NULL;
+ }
+
+ if (!s->s_root) {
+ /* initial superblock/root creation */
+ s->s_flags = flags;
+ nfs_clone_super(s, data->sb);
+ }
+
+ mntroot = nfs_get_root(s, data->fh);
+ if (IS_ERR(mntroot)) {
+ error = PTR_ERR(mntroot);
+ goto error_splat_super;
+ }
+
+ s->s_flags |= MS_ACTIVE;
+ mnt->mnt_sb = s;
+ mnt->mnt_root = mntroot;
+
+ dprintk("<-- nfs_xdev_get_sb() = 0\n");
+ return 0;
+
+out_err_nosb:
+ nfs_free_server(server);
+out_err_noserver:
+ dprintk("<-- nfs_xdev_get_sb() = %d [error]\n", error);
+ return error;
+
+error_splat_super:
+ up_write(&s->s_umount);
+ deactivate_super(s);
+ dprintk("<-- nfs_xdev_get_sb() = %d [splat]\n", error);
+ return error;
+}
+
+#ifdef CONFIG_NFS_V4
+
+/*
+ * Finish setting up a cloned NFS4 superblock
+ */
+static void nfs4_clone_super(struct super_block *sb,
+ const struct super_block *old_sb)
+{
+ sb->s_blocksize_bits = old_sb->s_blocksize_bits;
+ sb->s_blocksize = old_sb->s_blocksize;
+ sb->s_maxbytes = old_sb->s_maxbytes;
+ sb->s_time_gran = 1;
+ sb->s_op = old_sb->s_op;
+ nfs_initialise_sb(sb);
+}
+
+/*
+ * Set up an NFS4 superblock
+ */
+static void nfs4_fill_super(struct super_block *sb)
+{
+ sb->s_time_gran = 1;
+ sb->s_op = &nfs4_sops;
+ nfs_initialise_sb(sb);
+}
+
+static void *nfs_copy_user_string(char *dst, struct nfs_string *src, int maxlen)
+{
+ void *p = NULL;
+
+ if (!src->len)
+ return ERR_PTR(-EINVAL);
+ if (src->len < maxlen)
+ maxlen = src->len;
+ if (dst == NULL) {
+ p = dst = kmalloc(maxlen + 1, GFP_KERNEL);
+ if (p == NULL)
+ return ERR_PTR(-ENOMEM);
+ }
+ if (copy_from_user(dst, src->data, maxlen)) {
+ kfree(p);
+ return ERR_PTR(-EFAULT);
+ }
+ dst[maxlen] = '\0';
+ return dst;
+}
+
+/*
+ * Get the superblock for an NFS4 mountpoint
+ */
+static int nfs4_get_sb(struct file_system_type *fs_type,
+ int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt)
+{
+ struct nfs4_mount_data *data = raw_data;
+ struct super_block *s;
+ struct nfs_server *server;
+ struct sockaddr_in addr;
+ rpc_authflavor_t authflavour;
+ struct nfs_fh mntfh;
+ struct dentry *mntroot;
+ char *mntpath = NULL, *hostname = NULL, ip_addr[16];
+ void *p;
+ int error;
+
+ if (data == NULL) {
+ dprintk("%s: missing data argument\n", __FUNCTION__);
+ return -EINVAL;
+ }
+ if (data->version <= 0 || data->version > NFS4_MOUNT_VERSION) {
+ dprintk("%s: bad mount version\n", __FUNCTION__);
+ return -EINVAL;
+ }
+
+ /* We now require that the mount process passes the remote address */
+ if (data->host_addrlen != sizeof(addr))
+ return -EINVAL;
+
+ if (copy_from_user(&addr, data->host_addr, sizeof(addr)))
+ return -EFAULT;
+
+ if (addr.sin_family != AF_INET ||
+ addr.sin_addr.s_addr == INADDR_ANY
+ ) {
+ dprintk("%s: mount program didn't pass remote IP address!\n",
+ __FUNCTION__);
+ return -EINVAL;
+ }
+ /* RFC3530: The default port for NFS is 2049 */
+ if (addr.sin_port == 0)
+ addr.sin_port = NFS_PORT;
+
+ /* Grab the authentication type */
+ authflavour = RPC_AUTH_UNIX;
+ if (data->auth_flavourlen != 0) {
+ if (data->auth_flavourlen != 1) {
+ dprintk("%s: Invalid number of RPC auth flavours %d.\n",
+ __FUNCTION__, data->auth_flavourlen);
+ error = -EINVAL;
+ goto out_err_noserver;
+ }
+
+ if (copy_from_user(&authflavour, data->auth_flavours,
+ sizeof(authflavour))) {
+ error = -EFAULT;
+ goto out_err_noserver;
+ }
+ }
+
+ p = nfs_copy_user_string(NULL, &data->hostname, 256);
+ if (IS_ERR(p))
+ goto out_err;
+ hostname = p;
+
+ p = nfs_copy_user_string(NULL, &data->mnt_path, 1024);
+ if (IS_ERR(p))
+ goto out_err;
+ mntpath = p;
+
+ dprintk("MNTPATH: %s\n", mntpath);
+
+ p = nfs_copy_user_string(ip_addr, &data->client_addr,
+ sizeof(ip_addr) - 1);
+ if (IS_ERR(p))
+ goto out_err;
+
+ /* Get a volume representation */
+ server = nfs4_create_server(data, hostname, &addr, mntpath, ip_addr,
+ authflavour, &mntfh);
+ if (IS_ERR(server)) {
+ error = PTR_ERR(server);
+ goto out_err_noserver;
+ }
+
+ /* Get a superblock - note that we may end up sharing one that already exists */
+ s = sget(fs_type, nfs_compare_super, nfs_set_super, server);
+ if (IS_ERR(s)) {
+ error = PTR_ERR(s);
+ goto out_free;
+ }
+
+ if (s->s_fs_info != server) {
+ nfs_free_server(server);
+ server = NULL;
+ }
+
+ if (!s->s_root) {
+ /* initial superblock/root creation */
+ s->s_flags = flags;
+ nfs4_fill_super(s);
+ }
+
+ mntroot = nfs4_get_root(s, &mntfh);
+ if (IS_ERR(mntroot)) {
+ error = PTR_ERR(mntroot);
+ goto error_splat_super;
+ }
+
+ s->s_flags |= MS_ACTIVE;
+ mnt->mnt_sb = s;
+ mnt->mnt_root = mntroot;
+ kfree(mntpath);
+ kfree(hostname);
+ return 0;
+
+out_err:
+ error = PTR_ERR(p);
+ goto out_err_noserver;
+
+out_free:
+ nfs_free_server(server);
+out_err_noserver:
+ kfree(mntpath);
+ kfree(hostname);
+ return error;
+
+error_splat_super:
+ up_write(&s->s_umount);
+ deactivate_super(s);
+ goto out_err_noserver;
+}
+
+static void nfs4_kill_super(struct super_block *sb)
+{
+ struct nfs_server *server = NFS_SB(sb);
+
+ nfs_return_all_delegations(sb);
+ kill_anon_super(sb);
+
+ nfs4_renewd_prepare_shutdown(server);
+ nfs_free_server(server);
+}
+
+/*
+ * Clone an NFS4 server record on xdev traversal (FSID-change)
+ */
+static int nfs4_xdev_get_sb(struct file_system_type *fs_type, int flags,
+ const char *dev_name, void *raw_data,
+ struct vfsmount *mnt)
+{
+ struct nfs_clone_mount *data = raw_data;
+ struct super_block *s;
+ struct nfs_server *server;
+ struct dentry *mntroot;
+ int error;
+
+ dprintk("--> nfs4_xdev_get_sb()\n");
+
+ /* create a new volume representation */
+ server = nfs_clone_server(NFS_SB(data->sb), data->fh, data->fattr);
+ if (IS_ERR(server)) {
+ error = PTR_ERR(server);
+ goto out_err_noserver;
+ }
+
+ /* Get a superblock - note that we may end up sharing one that already exists */
+ s = sget(&nfs_fs_type, nfs_compare_super, nfs_set_super, server);
+ if (IS_ERR(s)) {
+ error = PTR_ERR(s);
+ goto out_err_nosb;
+ }
+
+ if (s->s_fs_info != server) {
+ nfs_free_server(server);
+ server = NULL;
+ }
+
+ if (!s->s_root) {
+ /* initial superblock/root creation */
+ s->s_flags = flags;
+ nfs4_clone_super(s, data->sb);
+ }
+
+ mntroot = nfs4_get_root(s, data->fh);
+ if (IS_ERR(mntroot)) {
+ error = PTR_ERR(mntroot);
+ goto error_splat_super;
+ }
+
+ s->s_flags |= MS_ACTIVE;
+ mnt->mnt_sb = s;
+ mnt->mnt_root = mntroot;
+
+ dprintk("<-- nfs4_xdev_get_sb() = 0\n");
+ return 0;
+
+out_err_nosb:
+ nfs_free_server(server);
+out_err_noserver:
+ dprintk("<-- nfs4_xdev_get_sb() = %d [error]\n", error);
+ return error;
+
+error_splat_super:
+ up_write(&s->s_umount);
+ deactivate_super(s);
+ dprintk("<-- nfs4_xdev_get_sb() = %d [splat]\n", error);
+ return error;
+}
+
+/*
+ * Create an NFS4 server record on referral traversal
+ */
+static int nfs4_referral_get_sb(struct file_system_type *fs_type, int flags,
+ const char *dev_name, void *raw_data,
+ struct vfsmount *mnt)
+{
+ struct nfs_clone_mount *data = raw_data;
+ struct super_block *s;
+ struct nfs_server *server;
+ struct dentry *mntroot;
+ struct nfs_fh mntfh;
+ int error;
+
+ dprintk("--> nfs4_referral_get_sb()\n");
+
+ /* create a new volume representation */
+ server = nfs4_create_referral_server(data, &mntfh);
+ if (IS_ERR(server)) {
+ error = PTR_ERR(server);
+ goto out_err_noserver;
+ }
+
+ /* Get a superblock - note that we may end up sharing one that already exists */
+ s = sget(&nfs_fs_type, nfs_compare_super, nfs_set_super, server);
+ if (IS_ERR(s)) {
+ error = PTR_ERR(s);
+ goto out_err_nosb;
+ }
+
+ if (s->s_fs_info != server) {
+ nfs_free_server(server);
+ server = NULL;
+ }
+
+ if (!s->s_root) {
+ /* initial superblock/root creation */
+ s->s_flags = flags;
+ nfs4_fill_super(s);
+ }
+
+ mntroot = nfs4_get_root(s, data->fh);
+ if (IS_ERR(mntroot)) {
+ error = PTR_ERR(mntroot);
+ goto error_splat_super;
+ }
+
+ s->s_flags |= MS_ACTIVE;
+ mnt->mnt_sb = s;
+ mnt->mnt_root = mntroot;
+
+ dprintk("<-- nfs4_referral_get_sb() = 0\n");
+ return 0;
+
+out_err_nosb:
+ nfs_free_server(server);
+out_err_noserver:
+ dprintk("<-- nfs4_referral_get_sb() = %d [error]\n", error);
+ return error;
+
+error_splat_super:
+ up_write(&s->s_umount);
+ deactivate_super(s);
+ dprintk("<-- nfs4_referral_get_sb() = %d [splat]\n", error);
+ return error;
+}
+
+#endif /* CONFIG_NFS_V4 */