From: Bryan Schumaker Date: Mon, 16 Jul 2012 20:39:20 +0000 (-0400) Subject: NFS: Split out the NFS v4 filesystem types X-Git-Tag: firefly_0821_release~3680^2~2294^2~8 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=fbdefd6442811392e857721573b63a51d1149cc8;p=firefly-linux-kernel-4.4.55.git NFS: Split out the NFS v4 filesystem types This allows me to move the v4 mounting and unmounting functions out of the generic client and into a file that is only compiled when CONFIG_NFS_V4 is enabled. Signed-off-by: Bryan Schumaker Signed-off-by: Trond Myklebust --- diff --git a/fs/nfs/internal.h b/fs/nfs/internal.h index b4a35705246c..cfafd13b6fe9 100644 --- a/fs/nfs/internal.h +++ b/fs/nfs/internal.h @@ -153,6 +153,14 @@ struct nfs_mount_request { struct net *net; }; +struct nfs_mount_info { + void (*fill_super)(struct super_block *, struct nfs_mount_info *); + int (*set_security)(struct super_block *, struct dentry *, struct nfs_mount_info *); + struct nfs_parsed_mount_data *parsed; + struct nfs_clone_mount *cloned; + struct nfs_fh *mntfh; +}; + extern int nfs_mount(struct nfs_mount_request *info); extern void nfs_umount(const struct nfs_mount_request *info); @@ -318,6 +326,16 @@ extern struct file_system_type nfs_xdev_fs_type; extern struct file_system_type nfs4_xdev_fs_type; extern struct file_system_type nfs4_referral_fs_type; #endif +void nfs_initialise_sb(struct super_block *); +int nfs_set_sb_security(struct super_block *, struct dentry *, struct nfs_mount_info *); +int nfs_clone_sb_security(struct super_block *, struct dentry *, struct nfs_mount_info *); +struct dentry *nfs_fs_mount_common(struct file_system_type *, struct nfs_server *, + int, const char *, struct nfs_mount_info *); +struct dentry *nfs_fs_mount(struct file_system_type *, int, const char *, void *); +struct dentry * nfs_xdev_mount_common(struct file_system_type *, int, + const char *, struct nfs_mount_info *); +void nfs_kill_super(struct super_block *); +void nfs_fill_super(struct super_block *, struct nfs_mount_info *); extern struct rpc_stat nfs_rpcstat; @@ -364,6 +382,17 @@ extern void nfs_pageio_init_read(struct nfs_pageio_descriptor *pgio, extern void nfs_pageio_reset_read_mds(struct nfs_pageio_descriptor *pgio); extern void nfs_readdata_release(struct nfs_read_data *rdata); +/* super.c */ +void nfs_clone_super(struct super_block *, struct nfs_mount_info *); +void nfs_umount_begin(struct super_block *); +int nfs_statfs(struct dentry *, struct kstatfs *); +int nfs_show_options(struct seq_file *, struct dentry *); +int nfs_show_devname(struct seq_file *, struct dentry *); +int nfs_show_path(struct seq_file *, struct dentry *); +int nfs_show_stats(struct seq_file *, struct dentry *); +void nfs_put_super(struct super_block *); +int nfs_remount(struct super_block *sb, int *flags, char *raw_data); + /* write.c */ extern void nfs_pageio_init_write(struct nfs_pageio_descriptor *pgio, struct inode *inode, int ioflags, diff --git a/fs/nfs/nfs4_fs.h b/fs/nfs/nfs4_fs.h index b508fef1a32b..b1ecacd8784a 100644 --- a/fs/nfs/nfs4_fs.h +++ b/fs/nfs/nfs4_fs.h @@ -365,6 +365,8 @@ extern void nfs4_free_lock_state(struct nfs_server *server, struct nfs4_lock_sta extern const nfs4_stateid zero_stateid; /* nfs4super.c */ +struct nfs_mount_info; +struct dentry *nfs4_try_mount(int, const char *, struct nfs_mount_info *); int init_nfs_v4(void); void exit_nfs_v4(void); diff --git a/fs/nfs/nfs4super.c b/fs/nfs/nfs4super.c index 70c394e75ca1..2af26913884f 100644 --- a/fs/nfs/nfs4super.c +++ b/fs/nfs/nfs4super.c @@ -2,10 +2,331 @@ * Copyright (c) 2012 Bryan Schumaker */ #include +#include #include +#include #include +#include "internal.h" #include "nfs4_fs.h" +#define NFSDBG_FACILITY NFSDBG_VFS + +static struct dentry *nfs4_remote_mount(struct file_system_type *fs_type, + int flags, const char *dev_name, void *raw_data); +static struct dentry *nfs4_xdev_mount(struct file_system_type *fs_type, + int flags, const char *dev_name, void *raw_data); +static struct dentry *nfs4_referral_mount(struct file_system_type *fs_type, + int flags, const char *dev_name, void *raw_data); +static struct dentry *nfs4_remote_referral_mount(struct file_system_type *fs_type, + int flags, const char *dev_name, void *raw_data); + +static struct file_system_type nfs4_fs_type = { + .owner = THIS_MODULE, + .name = "nfs4", + .mount = nfs_fs_mount, + .kill_sb = nfs_kill_super, + .fs_flags = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA, +}; + +static struct file_system_type nfs4_remote_fs_type = { + .owner = THIS_MODULE, + .name = "nfs4", + .mount = nfs4_remote_mount, + .kill_sb = nfs_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", + .mount = nfs4_xdev_mount, + .kill_sb = nfs_kill_super, + .fs_flags = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA, +}; + +static struct file_system_type nfs4_remote_referral_fs_type = { + .owner = THIS_MODULE, + .name = "nfs4", + .mount = nfs4_remote_referral_mount, + .kill_sb = nfs_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", + .mount = nfs4_referral_mount, + .kill_sb = nfs_kill_super, + .fs_flags = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA, +}; + +static const struct super_operations nfs4_sops = { + .alloc_inode = nfs_alloc_inode, + .destroy_inode = nfs_destroy_inode, + .write_inode = nfs4_write_inode, + .put_super = nfs_put_super, + .statfs = nfs_statfs, + .evict_inode = nfs4_evict_inode, + .umount_begin = nfs_umount_begin, + .show_options = nfs_show_options, + .show_devname = nfs_show_devname, + .show_path = nfs_show_path, + .show_stats = nfs_show_stats, + .remount_fs = nfs_remount, +}; + +/* + * Set up an NFS4 superblock + */ +static void nfs4_fill_super(struct super_block *sb, + struct nfs_mount_info *mount_info) +{ + sb->s_time_gran = 1; + sb->s_op = &nfs4_sops; + /* + * The VFS shouldn't apply the umask to mode bits. We will do + * so ourselves when necessary. + */ + sb->s_flags |= MS_POSIXACL; + sb->s_xattr = nfs4_xattr_handlers; + nfs_initialise_sb(sb); +} + +/* + * Get the superblock for the NFS4 root partition + */ +static struct dentry * +nfs4_remote_mount(struct file_system_type *fs_type, int flags, + const char *dev_name, void *info) +{ + struct nfs_mount_info *mount_info = info; + struct nfs_server *server; + struct dentry *mntroot = ERR_PTR(-ENOMEM); + + mount_info->fill_super = nfs4_fill_super; + mount_info->set_security = nfs_set_sb_security; + + /* Get a volume representation */ + server = nfs4_create_server(mount_info->parsed, mount_info->mntfh); + if (IS_ERR(server)) { + mntroot = ERR_CAST(server); + goto out; + } + + mntroot = nfs_fs_mount_common(fs_type, server, flags, dev_name, mount_info); + +out: + return mntroot; +} + +static struct vfsmount *nfs_do_root_mount(struct file_system_type *fs_type, + int flags, void *data, const char *hostname) +{ + struct vfsmount *root_mnt; + char *root_devname; + size_t len; + + len = strlen(hostname) + 5; + root_devname = kmalloc(len, GFP_KERNEL); + if (root_devname == NULL) + return ERR_PTR(-ENOMEM); + /* Does hostname needs to be enclosed in brackets? */ + if (strchr(hostname, ':')) + snprintf(root_devname, len, "[%s]:/", hostname); + else + snprintf(root_devname, len, "%s:/", hostname); + root_mnt = vfs_kern_mount(fs_type, flags, root_devname, data); + kfree(root_devname); + return root_mnt; +} + +struct nfs_referral_count { + struct list_head list; + const struct task_struct *task; + unsigned int referral_count; +}; + +static LIST_HEAD(nfs_referral_count_list); +static DEFINE_SPINLOCK(nfs_referral_count_list_lock); + +static struct nfs_referral_count *nfs_find_referral_count(void) +{ + struct nfs_referral_count *p; + + list_for_each_entry(p, &nfs_referral_count_list, list) { + if (p->task == current) + return p; + } + return NULL; +} + +#define NFS_MAX_NESTED_REFERRALS 2 + +static int nfs_referral_loop_protect(void) +{ + struct nfs_referral_count *p, *new; + int ret = -ENOMEM; + + new = kmalloc(sizeof(*new), GFP_KERNEL); + if (!new) + goto out; + new->task = current; + new->referral_count = 1; + + ret = 0; + spin_lock(&nfs_referral_count_list_lock); + p = nfs_find_referral_count(); + if (p != NULL) { + if (p->referral_count >= NFS_MAX_NESTED_REFERRALS) + ret = -ELOOP; + else + p->referral_count++; + } else { + list_add(&new->list, &nfs_referral_count_list); + new = NULL; + } + spin_unlock(&nfs_referral_count_list_lock); + kfree(new); +out: + return ret; +} + +static void nfs_referral_loop_unprotect(void) +{ + struct nfs_referral_count *p; + + spin_lock(&nfs_referral_count_list_lock); + p = nfs_find_referral_count(); + p->referral_count--; + if (p->referral_count == 0) + list_del(&p->list); + else + p = NULL; + spin_unlock(&nfs_referral_count_list_lock); + kfree(p); +} + +static struct dentry *nfs_follow_remote_path(struct vfsmount *root_mnt, + const char *export_path) +{ + struct dentry *dentry; + int err; + + if (IS_ERR(root_mnt)) + return ERR_CAST(root_mnt); + + err = nfs_referral_loop_protect(); + if (err) { + mntput(root_mnt); + return ERR_PTR(err); + } + + dentry = mount_subtree(root_mnt, export_path); + nfs_referral_loop_unprotect(); + + return dentry; +} + +struct dentry *nfs4_try_mount(int flags, const char *dev_name, + struct nfs_mount_info *mount_info) +{ + char *export_path; + struct vfsmount *root_mnt; + struct dentry *res; + struct nfs_parsed_mount_data *data = mount_info->parsed; + + dfprintk(MOUNT, "--> nfs4_try_mount()\n"); + + mount_info->fill_super = nfs4_fill_super; + + export_path = data->nfs_server.export_path; + data->nfs_server.export_path = "/"; + root_mnt = nfs_do_root_mount(&nfs4_remote_fs_type, flags, mount_info, + data->nfs_server.hostname); + data->nfs_server.export_path = export_path; + + res = nfs_follow_remote_path(root_mnt, export_path); + + dfprintk(MOUNT, "<-- nfs4_try_mount() = %ld%s\n", + IS_ERR(res) ? PTR_ERR(res) : 0, + IS_ERR(res) ? " [error]" : ""); + return res; +} + +/* + * Clone an NFS4 server record on xdev traversal (FSID-change) + */ +static struct dentry * +nfs4_xdev_mount(struct file_system_type *fs_type, int flags, + const char *dev_name, void *raw_data) +{ + struct nfs_mount_info mount_info = { + .fill_super = nfs_clone_super, + .set_security = nfs_clone_sb_security, + .cloned = raw_data, + }; + return nfs_xdev_mount_common(&nfs4_fs_type, flags, dev_name, &mount_info); +} + +static struct dentry * +nfs4_remote_referral_mount(struct file_system_type *fs_type, int flags, + const char *dev_name, void *raw_data) +{ + struct nfs_mount_info mount_info = { + .fill_super = nfs4_fill_super, + .set_security = nfs_clone_sb_security, + .cloned = raw_data, + }; + struct nfs_server *server; + struct dentry *mntroot = ERR_PTR(-ENOMEM); + + dprintk("--> nfs4_referral_get_sb()\n"); + + mount_info.mntfh = nfs_alloc_fhandle(); + if (mount_info.cloned == NULL || mount_info.mntfh == NULL) + goto out; + + /* create a new volume representation */ + server = nfs4_create_referral_server(mount_info.cloned, mount_info.mntfh); + if (IS_ERR(server)) { + mntroot = ERR_CAST(server); + goto out; + } + + mntroot = nfs_fs_mount_common(&nfs4_fs_type, server, flags, dev_name, &mount_info); +out: + nfs_free_fhandle(mount_info.mntfh); + return mntroot; +} + +/* + * Create an NFS4 server record on referral traversal + */ +static struct dentry *nfs4_referral_mount(struct file_system_type *fs_type, + int flags, const char *dev_name, void *raw_data) +{ + struct nfs_clone_mount *data = raw_data; + char *export_path; + struct vfsmount *root_mnt; + struct dentry *res; + + dprintk("--> nfs4_referral_mount()\n"); + + export_path = data->mnt_path; + data->mnt_path = "/"; + + root_mnt = nfs_do_root_mount(&nfs4_remote_referral_fs_type, + flags, data, data->hostname); + data->mnt_path = export_path; + + res = nfs_follow_remote_path(root_mnt, export_path); + dprintk("<-- nfs4_referral_mount() = %ld%s\n", + IS_ERR(res) ? PTR_ERR(res) : 0, + IS_ERR(res) ? " [error]" : ""); + return res; +} + + int __init init_nfs_v4(void) { int err; @@ -18,7 +339,13 @@ int __init init_nfs_v4(void) if (err) goto out1; + err = register_filesystem(&nfs4_fs_type); + if (err < 0) + goto out2; + return 0; +out2: + nfs4_unregister_sysctl(); out1: nfs_idmap_quit(); out: @@ -27,6 +354,7 @@ out: void __exit exit_nfs_v4(void) { + unregister_filesystem(&nfs4_fs_type); nfs4_unregister_sysctl(); nfs_idmap_quit(); } diff --git a/fs/nfs/super.c b/fs/nfs/super.c index ca3c0e8cf774..95866a8c21bb 100644 --- a/fs/nfs/super.c +++ b/fs/nfs/super.c @@ -278,29 +278,8 @@ static match_table_t nfs_vers_tokens = { { Opt_vers_err, NULL } }; -struct nfs_mount_info { - void (*fill_super)(struct super_block *, struct nfs_mount_info *); - int (*set_security)(struct super_block *, struct dentry *, struct nfs_mount_info *); - struct nfs_parsed_mount_data *parsed; - struct nfs_clone_mount *cloned; - struct nfs_fh *mntfh; -}; - -static void nfs_umount_begin(struct super_block *); -static int nfs_statfs(struct dentry *, struct kstatfs *); -static int nfs_show_options(struct seq_file *, struct dentry *); -static int nfs_show_devname(struct seq_file *, struct dentry *); -static int nfs_show_path(struct seq_file *, struct dentry *); -static int nfs_show_stats(struct seq_file *, struct dentry *); -static struct dentry *nfs_fs_mount_common(struct file_system_type *, - struct nfs_server *, int, const char *, struct nfs_mount_info *); -static struct dentry *nfs_fs_mount(struct file_system_type *, - int, const char *, void *); static struct dentry *nfs_xdev_mount(struct file_system_type *fs_type, int flags, const char *dev_name, void *raw_data); -static void nfs_put_super(struct super_block *); -static void nfs_kill_super(struct super_block *); -static int nfs_remount(struct super_block *sb, int *flags, char *raw_data); static struct file_system_type nfs_fs_type = { .owner = THIS_MODULE, @@ -337,71 +316,6 @@ static const struct super_operations nfs_sops = { static void nfs4_validate_mount_flags(struct nfs_parsed_mount_data *); static int nfs4_validate_mount_data(void *options, struct nfs_parsed_mount_data *args, const char *dev_name); -static struct dentry *nfs4_try_mount(int flags, const char *dev_name, - struct nfs_mount_info *mount_info); -static struct dentry *nfs4_remote_mount(struct file_system_type *fs_type, - int flags, const char *dev_name, void *raw_data); -static struct dentry *nfs4_xdev_mount(struct file_system_type *fs_type, - int flags, const char *dev_name, void *raw_data); -static struct dentry *nfs4_referral_mount(struct file_system_type *fs_type, - int flags, const char *dev_name, void *raw_data); -static struct dentry *nfs4_remote_referral_mount(struct file_system_type *fs_type, - int flags, const char *dev_name, void *raw_data); - -static struct file_system_type nfs4_fs_type = { - .owner = THIS_MODULE, - .name = "nfs4", - .mount = nfs_fs_mount, - .kill_sb = nfs_kill_super, - .fs_flags = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA, -}; - -static struct file_system_type nfs4_remote_fs_type = { - .owner = THIS_MODULE, - .name = "nfs4", - .mount = nfs4_remote_mount, - .kill_sb = nfs_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", - .mount = nfs4_xdev_mount, - .kill_sb = nfs_kill_super, - .fs_flags = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA, -}; - -static struct file_system_type nfs4_remote_referral_fs_type = { - .owner = THIS_MODULE, - .name = "nfs4", - .mount = nfs4_remote_referral_mount, - .kill_sb = nfs_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", - .mount = nfs4_referral_mount, - .kill_sb = nfs_kill_super, - .fs_flags = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA, -}; - -static const struct super_operations nfs4_sops = { - .alloc_inode = nfs_alloc_inode, - .destroy_inode = nfs_destroy_inode, - .write_inode = nfs4_write_inode, - .put_super = nfs_put_super, - .statfs = nfs_statfs, - .evict_inode = nfs4_evict_inode, - .umount_begin = nfs_umount_begin, - .show_options = nfs_show_options, - .show_devname = nfs_show_devname, - .show_path = nfs_show_path, - .show_stats = nfs_show_stats, - .remount_fs = nfs_remount, -}; #endif static struct shrinker acl_shrinker = { @@ -423,18 +337,9 @@ int __init register_nfs_fs(void) ret = nfs_register_sysctl(); if (ret < 0) goto error_1; -#ifdef CONFIG_NFS_V4 - ret = register_filesystem(&nfs4_fs_type); - if (ret < 0) - goto error_2; -#endif register_shrinker(&acl_shrinker); return 0; -#ifdef CONFIG_NFS_V4 -error_2: - nfs_unregister_sysctl(); -#endif error_1: unregister_filesystem(&nfs_fs_type); error_0: @@ -447,9 +352,6 @@ error_0: void __exit unregister_nfs_fs(void) { unregister_shrinker(&acl_shrinker); -#ifdef CONFIG_NFS_V4 - unregister_filesystem(&nfs4_fs_type); -#endif nfs_unregister_sysctl(); unregister_filesystem(&nfs_fs_type); } @@ -473,7 +375,7 @@ void nfs_sb_deactive(struct super_block *sb) /* * Deliver file system statistics to userspace */ -static int nfs_statfs(struct dentry *dentry, struct kstatfs *buf) +int nfs_statfs(struct dentry *dentry, struct kstatfs *buf) { struct nfs_server *server = NFS_SB(dentry->d_sb); unsigned char blockbits; @@ -756,7 +658,7 @@ static void nfs_show_mount_options(struct seq_file *m, struct nfs_server *nfss, /* * Describe the mount options on this VFS mountpoint */ -static int nfs_show_options(struct seq_file *m, struct dentry *root) +int nfs_show_options(struct seq_file *m, struct dentry *root) { struct nfs_server *nfss = NFS_SB(root->d_sb); @@ -814,7 +716,7 @@ static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss) } #endif -static int nfs_show_devname(struct seq_file *m, struct dentry *root) +int nfs_show_devname(struct seq_file *m, struct dentry *root) { char *page = (char *) __get_free_page(GFP_KERNEL); char *devname, *dummy; @@ -830,7 +732,7 @@ static int nfs_show_devname(struct seq_file *m, struct dentry *root) return err; } -static int nfs_show_path(struct seq_file *m, struct dentry *dentry) +int nfs_show_path(struct seq_file *m, struct dentry *dentry) { seq_puts(m, "/"); return 0; @@ -839,7 +741,7 @@ static int nfs_show_path(struct seq_file *m, struct dentry *dentry) /* * Present statistical information for this VFS mountpoint */ -static int nfs_show_stats(struct seq_file *m, struct dentry *root) +int nfs_show_stats(struct seq_file *m, struct dentry *root) { int i, cpu; struct nfs_server *nfss = NFS_SB(root->d_sb); @@ -932,7 +834,7 @@ static int nfs_show_stats(struct seq_file *m, struct dentry *root) * Begin unmount by attempting to remove all automounted mountpoints we added * in response to xdev traversals and referrals */ -static void nfs_umount_begin(struct super_block *sb) +void nfs_umount_begin(struct super_block *sb) { struct nfs_server *server; struct rpc_clnt *rpc; @@ -2107,7 +2009,7 @@ nfs_compare_remount_data(struct nfs_server *nfss, return 0; } -static int +int nfs_remount(struct super_block *sb, int *flags, char *raw_data) { int error; @@ -2172,7 +2074,7 @@ out: /* * Initialise the common bits of the superblock */ -static inline void nfs_initialise_sb(struct super_block *sb) +inline void nfs_initialise_sb(struct super_block *sb) { struct nfs_server *server = NFS_SB(sb); @@ -2194,8 +2096,7 @@ static inline void nfs_initialise_sb(struct super_block *sb) /* * Finish setting up an NFS2/3 superblock */ -static void nfs_fill_super(struct super_block *sb, - struct nfs_mount_info *mount_info) +void nfs_fill_super(struct super_block *sb, struct nfs_mount_info *mount_info) { struct nfs_parsed_mount_data *data = mount_info->parsed; struct nfs_server *server = NFS_SB(sb); @@ -2220,8 +2121,7 @@ static void nfs_fill_super(struct super_block *sb, /* * Finish setting up a cloned NFS2/3/4 superblock */ -static void nfs_clone_super(struct super_block *sb, - struct nfs_mount_info *mount_info) +void nfs_clone_super(struct super_block *sb, struct nfs_mount_info *mount_info) { const struct super_block *old_sb = mount_info->cloned->sb; struct nfs_server *server = NFS_SB(sb); @@ -2381,14 +2281,14 @@ static int nfs_bdi_register(struct nfs_server *server) return bdi_register_dev(&server->backing_dev_info, server->s_dev); } -static int nfs_set_sb_security(struct super_block *s, struct dentry *mntroot, - struct nfs_mount_info *mount_info) +int nfs_set_sb_security(struct super_block *s, struct dentry *mntroot, + struct nfs_mount_info *mount_info) { return security_sb_set_mnt_opts(s, &mount_info->parsed->lsm_opts); } -static int nfs_clone_sb_security(struct super_block *s, struct dentry *mntroot, - struct nfs_mount_info *mount_info) +int nfs_clone_sb_security(struct super_block *s, struct dentry *mntroot, + struct nfs_mount_info *mount_info) { /* clone any lsm security options from the parent to the new sb */ security_sb_clone_mnt_opts(mount_info->cloned->sb, s); @@ -2397,10 +2297,10 @@ static int nfs_clone_sb_security(struct super_block *s, struct dentry *mntroot, return 0; } -static struct dentry *nfs_fs_mount_common(struct file_system_type *fs_type, - struct nfs_server *server, - int flags, const char *dev_name, - struct nfs_mount_info *mount_info) +struct dentry *nfs_fs_mount_common(struct file_system_type *fs_type, + struct nfs_server *server, + int flags, const char *dev_name, + struct nfs_mount_info *mount_info) { struct super_block *s; struct dentry *mntroot = ERR_PTR(-ENOMEM); @@ -2470,7 +2370,7 @@ error_splat_bdi: goto out; } -static struct dentry *nfs_fs_mount(struct file_system_type *fs_type, +struct dentry *nfs_fs_mount(struct file_system_type *fs_type, int flags, const char *dev_name, void *raw_data) { struct nfs_mount_info mount_info = { @@ -2511,7 +2411,7 @@ out: * Ensure that we unregister the bdi before kill_anon_super * releases the device name */ -static void nfs_put_super(struct super_block *s) +void nfs_put_super(struct super_block *s) { struct nfs_server *server = NFS_SB(s); @@ -2521,7 +2421,7 @@ static void nfs_put_super(struct super_block *s) /* * Destroy an NFS2/3 superblock */ -static void nfs_kill_super(struct super_block *s) +void nfs_kill_super(struct super_block *s) { struct nfs_server *server = NFS_SB(s); @@ -2533,7 +2433,7 @@ static void nfs_kill_super(struct super_block *s) /* * Clone an NFS2/3/4 server record on xdev traversal (FSID-change) */ -static struct dentry * +struct dentry * nfs_xdev_mount_common(struct file_system_type *fs_type, int flags, const char *dev_name, struct nfs_mount_info *mount_info) { @@ -2580,23 +2480,6 @@ nfs_xdev_mount(struct file_system_type *fs_type, int flags, #ifdef CONFIG_NFS_V4 -/* - * Set up an NFS4 superblock - */ -static void nfs4_fill_super(struct super_block *sb, - struct nfs_mount_info *mount_info) -{ - sb->s_time_gran = 1; - sb->s_op = &nfs4_sops; - /* - * The VFS shouldn't apply the umask to mode bits. We will do - * so ourselves when necessary. - */ - sb->s_flags |= MS_POSIXACL; - sb->s_xattr = nfs4_xattr_handlers; - nfs_initialise_sb(sb); -} - static void nfs4_validate_mount_flags(struct nfs_parsed_mount_data *args) { args->flags &= ~(NFS_MOUNT_NONLM|NFS_MOUNT_NOACL|NFS_MOUNT_VER3| @@ -2694,238 +2577,4 @@ out_no_address: return -EINVAL; } -/* - * Get the superblock for the NFS4 root partition - */ -static struct dentry * -nfs4_remote_mount(struct file_system_type *fs_type, int flags, - const char *dev_name, void *info) -{ - struct nfs_mount_info *mount_info = info; - struct nfs_server *server; - struct dentry *mntroot = ERR_PTR(-ENOMEM); - - mount_info->fill_super = nfs4_fill_super; - mount_info->set_security = nfs_set_sb_security; - - /* Get a volume representation */ - server = nfs4_create_server(mount_info->parsed, mount_info->mntfh); - if (IS_ERR(server)) { - mntroot = ERR_CAST(server); - goto out; - } - - mntroot = nfs_fs_mount_common(fs_type, server, flags, dev_name, mount_info); - -out: - return mntroot; -} - -static struct vfsmount *nfs_do_root_mount(struct file_system_type *fs_type, - int flags, void *data, const char *hostname) -{ - struct vfsmount *root_mnt; - char *root_devname; - size_t len; - - len = strlen(hostname) + 5; - root_devname = kmalloc(len, GFP_KERNEL); - if (root_devname == NULL) - return ERR_PTR(-ENOMEM); - /* Does hostname needs to be enclosed in brackets? */ - if (strchr(hostname, ':')) - snprintf(root_devname, len, "[%s]:/", hostname); - else - snprintf(root_devname, len, "%s:/", hostname); - root_mnt = vfs_kern_mount(fs_type, flags, root_devname, data); - kfree(root_devname); - return root_mnt; -} - -struct nfs_referral_count { - struct list_head list; - const struct task_struct *task; - unsigned int referral_count; -}; - -static LIST_HEAD(nfs_referral_count_list); -static DEFINE_SPINLOCK(nfs_referral_count_list_lock); - -static struct nfs_referral_count *nfs_find_referral_count(void) -{ - struct nfs_referral_count *p; - - list_for_each_entry(p, &nfs_referral_count_list, list) { - if (p->task == current) - return p; - } - return NULL; -} - -#define NFS_MAX_NESTED_REFERRALS 2 - -static int nfs_referral_loop_protect(void) -{ - struct nfs_referral_count *p, *new; - int ret = -ENOMEM; - - new = kmalloc(sizeof(*new), GFP_KERNEL); - if (!new) - goto out; - new->task = current; - new->referral_count = 1; - - ret = 0; - spin_lock(&nfs_referral_count_list_lock); - p = nfs_find_referral_count(); - if (p != NULL) { - if (p->referral_count >= NFS_MAX_NESTED_REFERRALS) - ret = -ELOOP; - else - p->referral_count++; - } else { - list_add(&new->list, &nfs_referral_count_list); - new = NULL; - } - spin_unlock(&nfs_referral_count_list_lock); - kfree(new); -out: - return ret; -} - -static void nfs_referral_loop_unprotect(void) -{ - struct nfs_referral_count *p; - - spin_lock(&nfs_referral_count_list_lock); - p = nfs_find_referral_count(); - p->referral_count--; - if (p->referral_count == 0) - list_del(&p->list); - else - p = NULL; - spin_unlock(&nfs_referral_count_list_lock); - kfree(p); -} - -static struct dentry *nfs_follow_remote_path(struct vfsmount *root_mnt, - const char *export_path) -{ - struct dentry *dentry; - int err; - - if (IS_ERR(root_mnt)) - return ERR_CAST(root_mnt); - - err = nfs_referral_loop_protect(); - if (err) { - mntput(root_mnt); - return ERR_PTR(err); - } - - dentry = mount_subtree(root_mnt, export_path); - nfs_referral_loop_unprotect(); - - return dentry; -} - -static struct dentry *nfs4_try_mount(int flags, const char *dev_name, - struct nfs_mount_info *mount_info) -{ - char *export_path; - struct vfsmount *root_mnt; - struct dentry *res; - struct nfs_parsed_mount_data *data = mount_info->parsed; - - dfprintk(MOUNT, "--> nfs4_try_mount()\n"); - - mount_info->fill_super = nfs4_fill_super; - - export_path = data->nfs_server.export_path; - data->nfs_server.export_path = "/"; - root_mnt = nfs_do_root_mount(&nfs4_remote_fs_type, flags, mount_info, - data->nfs_server.hostname); - data->nfs_server.export_path = export_path; - - res = nfs_follow_remote_path(root_mnt, export_path); - - dfprintk(MOUNT, "<-- nfs4_try_mount() = %ld%s\n", - IS_ERR(res) ? PTR_ERR(res) : 0, - IS_ERR(res) ? " [error]" : ""); - return res; -} - -/* - * Clone an NFS4 server record on xdev traversal (FSID-change) - */ -static struct dentry * -nfs4_xdev_mount(struct file_system_type *fs_type, int flags, - const char *dev_name, void *raw_data) -{ - struct nfs_mount_info mount_info = { - .fill_super = nfs_clone_super, - .set_security = nfs_clone_sb_security, - .cloned = raw_data, - }; - return nfs_xdev_mount_common(&nfs4_fs_type, flags, dev_name, &mount_info); -} - -static struct dentry * -nfs4_remote_referral_mount(struct file_system_type *fs_type, int flags, - const char *dev_name, void *raw_data) -{ - struct nfs_mount_info mount_info = { - .fill_super = nfs4_fill_super, - .set_security = nfs_clone_sb_security, - .cloned = raw_data, - }; - struct nfs_server *server; - struct dentry *mntroot = ERR_PTR(-ENOMEM); - - dprintk("--> nfs4_referral_get_sb()\n"); - - mount_info.mntfh = nfs_alloc_fhandle(); - if (mount_info.cloned == NULL || mount_info.mntfh == NULL) - goto out; - - /* create a new volume representation */ - server = nfs4_create_referral_server(mount_info.cloned, mount_info.mntfh); - if (IS_ERR(server)) { - mntroot = ERR_CAST(server); - goto out; - } - - mntroot = nfs_fs_mount_common(&nfs4_fs_type, server, flags, dev_name, &mount_info); -out: - nfs_free_fhandle(mount_info.mntfh); - return mntroot; -} - -/* - * Create an NFS4 server record on referral traversal - */ -static struct dentry *nfs4_referral_mount(struct file_system_type *fs_type, - int flags, const char *dev_name, void *raw_data) -{ - struct nfs_clone_mount *data = raw_data; - char *export_path; - struct vfsmount *root_mnt; - struct dentry *res; - - dprintk("--> nfs4_referral_mount()\n"); - - export_path = data->mnt_path; - data->mnt_path = "/"; - - root_mnt = nfs_do_root_mount(&nfs4_remote_referral_fs_type, - flags, data, data->hostname); - data->mnt_path = export_path; - - res = nfs_follow_remote_path(root_mnt, export_path); - dprintk("<-- nfs4_referral_mount() = %ld%s\n", - IS_ERR(res) ? PTR_ERR(res) : 0, - IS_ERR(res) ? " [error]" : ""); - return res; -} - #endif /* CONFIG_NFS_V4 */