Orange Pi5 kernel

^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   1) // SPDX-License-Identifier: GPL-2.0-only
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   3)  * linux/fs/nfs/namespace.c
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   4)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   5)  * Copyright (C) 2005 Trond Myklebust <Trond.Myklebust@netapp.com>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   6)  * - Modified by David Howells <dhowells@redhat.com>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   7)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   8)  * NFS namespace
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   9)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  10) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  11) #include <linux/module.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  12) #include <linux/dcache.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  13) #include <linux/gfp.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  14) #include <linux/mount.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  15) #include <linux/namei.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  16) #include <linux/nfs_fs.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  17) #include <linux/string.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  18) #include <linux/sunrpc/clnt.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  19) #include <linux/vfs.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  20) #include <linux/sunrpc/gss_api.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  21) #include "internal.h"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  22) #include "nfs.h"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  23) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  24) #define NFSDBG_FACILITY		NFSDBG_VFS
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  25) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  26) static void nfs_expire_automounts(struct work_struct *work);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  27) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  28) static LIST_HEAD(nfs_automount_list);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  29) static DECLARE_DELAYED_WORK(nfs_automount_task, nfs_expire_automounts);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  30) int nfs_mountpoint_expiry_timeout = 500 * HZ;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  31) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  32) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  33)  * nfs_path - reconstruct the path given an arbitrary dentry
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  34)  * @base - used to return pointer to the end of devname part of path
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  35)  * @dentry_in - pointer to dentry
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  36)  * @buffer - result buffer
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  37)  * @buflen_in - length of buffer
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  38)  * @flags - options (see below)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  39)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  40)  * Helper function for constructing the server pathname
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  41)  * by arbitrary hashed dentry.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  42)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  43)  * This is mainly for use in figuring out the path on the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  44)  * server side when automounting on top of an existing partition
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  45)  * and in generating /proc/mounts and friends.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  46)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  47)  * Supported flags:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  48)  * NFS_PATH_CANONICAL: ensure there is exactly one slash after
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  49)  *		       the original device (export) name
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  50)  *		       (if unset, the original name is returned verbatim)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  51)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  52) char *nfs_path(char **p, struct dentry *dentry_in, char *buffer,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  53) 	       ssize_t buflen_in, unsigned flags)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  54) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  55) 	char *end;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  56) 	int namelen;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  57) 	unsigned seq;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  58) 	const char *base;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  59) 	struct dentry *dentry;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  60) 	ssize_t buflen;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  61) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  62) rename_retry:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  63) 	buflen = buflen_in;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  64) 	dentry = dentry_in;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  65) 	end = buffer+buflen;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  66) 	*--end = '\0';
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  67) 	buflen--;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  68) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  69) 	seq = read_seqbegin(&rename_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  70) 	rcu_read_lock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  71) 	while (1) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  72) 		spin_lock(&dentry->d_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  73) 		if (IS_ROOT(dentry))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  74) 			break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  75) 		namelen = dentry->d_name.len;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  76) 		buflen -= namelen + 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  77) 		if (buflen < 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  78) 			goto Elong_unlock;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  79) 		end -= namelen;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  80) 		memcpy(end, dentry->d_name.name, namelen);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  81) 		*--end = '/';
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  82) 		spin_unlock(&dentry->d_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  83) 		dentry = dentry->d_parent;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  84) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  85) 	if (read_seqretry(&rename_lock, seq)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  86) 		spin_unlock(&dentry->d_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  87) 		rcu_read_unlock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  88) 		goto rename_retry;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  89) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  90) 	if ((flags & NFS_PATH_CANONICAL) && *end != '/') {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  91) 		if (--buflen < 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  92) 			spin_unlock(&dentry->d_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  93) 			rcu_read_unlock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  94) 			goto Elong;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  95) 		}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  96) 		*--end = '/';
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  97) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  98) 	*p = end;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  99) 	base = dentry->d_fsdata;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100) 	if (!base) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) 		spin_unlock(&dentry->d_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102) 		rcu_read_unlock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103) 		WARN_ON(1);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) 		return end;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) 	namelen = strlen(base);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107) 	if (*end == '/') {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108) 		/* Strip off excess slashes in base string */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) 		while (namelen > 0 && base[namelen - 1] == '/')
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110) 			namelen--;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112) 	buflen -= namelen;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113) 	if (buflen < 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114) 		spin_unlock(&dentry->d_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115) 		rcu_read_unlock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116) 		goto Elong;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118) 	end -= namelen;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119) 	memcpy(end, base, namelen);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120) 	spin_unlock(&dentry->d_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) 	rcu_read_unlock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122) 	return end;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123) Elong_unlock:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124) 	spin_unlock(&dentry->d_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125) 	rcu_read_unlock();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126) 	if (read_seqretry(&rename_lock, seq))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127) 		goto rename_retry;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128) Elong:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129) 	return ERR_PTR(-ENAMETOOLONG);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131) EXPORT_SYMBOL_GPL(nfs_path);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134)  * nfs_d_automount - Handle crossing a mountpoint on the server
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 135)  * @path - The mountpoint
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 136)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 137)  * When we encounter a mountpoint on the server, we want to set up
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 138)  * a mountpoint on the client too, to prevent inode numbers from
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 139)  * colliding, and to allow "df" to work properly.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 140)  * On NFSv4, we also want to allow for the fact that different
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 141)  * filesystems may be migrated to different servers in a failover
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 142)  * situation, and that different filesystems may want to use
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 143)  * different security flavours.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 144)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 145) struct vfsmount *nfs_d_automount(struct path *path)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 146) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 147) 	struct nfs_fs_context *ctx;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 148) 	struct fs_context *fc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 149) 	struct vfsmount *mnt = ERR_PTR(-ENOMEM);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 150) 	struct nfs_server *server = NFS_SERVER(d_inode(path->dentry));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 151) 	struct nfs_client *client = server->nfs_client;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 152) 	int timeout = READ_ONCE(nfs_mountpoint_expiry_timeout);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 153) 	int ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 154) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 155) 	if (IS_ROOT(path->dentry))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 156) 		return ERR_PTR(-ESTALE);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 157) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 158) 	/* Open a new filesystem context, transferring parameters from the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 159) 	 * parent superblock, including the network namespace.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 160) 	 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 161) 	fc = fs_context_for_submount(path->mnt->mnt_sb->s_type, path->dentry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 162) 	if (IS_ERR(fc))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 163) 		return ERR_CAST(fc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 164) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 165) 	ctx = nfs_fc2context(fc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 166) 	ctx->clone_data.dentry	= path->dentry;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 167) 	ctx->clone_data.sb	= path->dentry->d_sb;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 168) 	ctx->clone_data.fattr	= nfs_alloc_fattr();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 169) 	if (!ctx->clone_data.fattr)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 170) 		goto out_fc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 171) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 172) 	if (fc->net_ns != client->cl_net) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 173) 		put_net(fc->net_ns);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 174) 		fc->net_ns = get_net(client->cl_net);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 175) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 176) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 177) 	/* for submounts we want the same server; referrals will reassign */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 178) 	memcpy(&ctx->nfs_server.address, &client->cl_addr, client->cl_addrlen);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 179) 	ctx->nfs_server.addrlen	= client->cl_addrlen;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 180) 	ctx->nfs_server.port	= server->port;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 181) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 182) 	ctx->version		= client->rpc_ops->version;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 183) 	ctx->minorversion	= client->cl_minorversion;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 184) 	ctx->nfs_mod		= client->cl_nfs_mod;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 185) 	__module_get(ctx->nfs_mod->owner);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 186) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 187) 	ret = client->rpc_ops->submount(fc, server);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 188) 	if (ret < 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 189) 		mnt = ERR_PTR(ret);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 190) 		goto out_fc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 191) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 192) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 193) 	up_write(&fc->root->d_sb->s_umount);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 194) 	mnt = vfs_create_mount(fc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 195) 	if (IS_ERR(mnt))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 196) 		goto out_fc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 197) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 198) 	mntget(mnt); /* prevent immediate expiration */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 199) 	if (timeout <= 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 200) 		goto out_fc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 201) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 202) 	mnt_set_expiry(mnt, &nfs_automount_list);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 203) 	schedule_delayed_work(&nfs_automount_task, timeout);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 204) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 205) out_fc:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 206) 	put_fs_context(fc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 207) 	return mnt;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 208) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 209) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 210) static int
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 211) nfs_namespace_getattr(const struct path *path, struct kstat *stat,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 212) 			u32 request_mask, unsigned int query_flags)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 213) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 214) 	if (NFS_FH(d_inode(path->dentry))->size != 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 215) 		return nfs_getattr(path, stat, request_mask, query_flags);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 216) 	generic_fillattr(d_inode(path->dentry), stat);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 217) 	return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 218) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 219) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 220) static int
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 221) nfs_namespace_setattr(struct dentry *dentry, struct iattr *attr)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 222) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 223) 	if (NFS_FH(d_inode(dentry))->size != 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 224) 		return nfs_setattr(dentry, attr);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 225) 	return -EACCES;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 226) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 227) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 228) const struct inode_operations nfs_mountpoint_inode_operations = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 229) 	.getattr	= nfs_getattr,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 230) 	.setattr	= nfs_setattr,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 231) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 232) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 233) const struct inode_operations nfs_referral_inode_operations = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 234) 	.getattr	= nfs_namespace_getattr,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 235) 	.setattr	= nfs_namespace_setattr,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 236) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 237) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 238) static void nfs_expire_automounts(struct work_struct *work)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 239) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 240) 	struct list_head *list = &nfs_automount_list;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 241) 	int timeout = READ_ONCE(nfs_mountpoint_expiry_timeout);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 242) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 243) 	mark_mounts_for_expiry(list);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 244) 	if (!list_empty(list) && timeout > 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 245) 		schedule_delayed_work(&nfs_automount_task, timeout);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 246) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 247) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 248) void nfs_release_automount_timer(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 249) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 250) 	if (list_empty(&nfs_automount_list))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 251) 		cancel_delayed_work(&nfs_automount_task);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 252) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 253) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 254) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 255)  * nfs_do_submount - set up mountpoint when crossing a filesystem boundary
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 256)  * @fc: pointer to struct nfs_fs_context
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 257)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 258)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 259) int nfs_do_submount(struct fs_context *fc)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 260) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 261) 	struct nfs_fs_context *ctx = nfs_fc2context(fc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 262) 	struct dentry *dentry = ctx->clone_data.dentry;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 263) 	struct nfs_server *server;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 264) 	char *buffer, *p;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 265) 	int ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 266) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 267) 	/* create a new volume representation */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 268) 	server = ctx->nfs_mod->rpc_ops->clone_server(NFS_SB(ctx->clone_data.sb),
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 269) 						     ctx->mntfh,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 270) 						     ctx->clone_data.fattr,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 271) 						     ctx->selected_flavor);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 272) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 273) 	if (IS_ERR(server))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 274) 		return PTR_ERR(server);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 275) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 276) 	ctx->server = server;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 277) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 278) 	buffer = kmalloc(4096, GFP_USER);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 279) 	if (!buffer)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 280) 		return -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 281) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 282) 	ctx->internal		= true;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 283) 	ctx->clone_data.inherited_bsize = ctx->clone_data.sb->s_blocksize_bits;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 284) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 285) 	p = nfs_devname(dentry, buffer, 4096);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 286) 	if (IS_ERR(p)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 287) 		nfs_errorf(fc, "NFS: Couldn't determine submount pathname");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 288) 		ret = PTR_ERR(p);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 289) 	} else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 290) 		ret = vfs_parse_fs_string(fc, "source", p, buffer + 4096 - p);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 291) 		if (!ret)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 292) 			ret = vfs_get_tree(fc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 293) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 294) 	kfree(buffer);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 295) 	return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 296) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 297) EXPORT_SYMBOL_GPL(nfs_do_submount);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 298) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 299) int nfs_submount(struct fs_context *fc, struct nfs_server *server)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 300) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 301) 	struct nfs_fs_context *ctx = nfs_fc2context(fc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 302) 	struct dentry *dentry = ctx->clone_data.dentry;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 303) 	struct dentry *parent = dget_parent(dentry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 304) 	int err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 305) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 306) 	/* Look it up again to get its attributes */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 307) 	err = server->nfs_client->rpc_ops->lookup(d_inode(parent), dentry,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 308) 						  ctx->mntfh, ctx->clone_data.fattr,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 309) 						  NULL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 310) 	dput(parent);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 311) 	if (err != 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 312) 		return err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 313) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 314) 	ctx->selected_flavor = server->client->cl_auth->au_flavor;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 315) 	return nfs_do_submount(fc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 316) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 317) EXPORT_SYMBOL_GPL(nfs_submount);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 318) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 319) static int param_set_nfs_timeout(const char *val, const struct kernel_param *kp)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 320) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 321) 	long num;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 322) 	int ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 323) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 324) 	if (!val)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 325) 		return -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 326) 	ret = kstrtol(val, 0, &num);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 327) 	if (ret)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 328) 		return -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 329) 	if (num > 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 330) 		if (num >= INT_MAX / HZ)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 331) 			num = INT_MAX;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 332) 		else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 333) 			num *= HZ;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 334) 		*((int *)kp->arg) = num;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 335) 		if (!list_empty(&nfs_automount_list))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 336) 			mod_delayed_work(system_wq, &nfs_automount_task, num);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 337) 	} else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 338) 		*((int *)kp->arg) = -1*HZ;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 339) 		cancel_delayed_work(&nfs_automount_task);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 340) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 341) 	return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 342) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 343) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 344) static int param_get_nfs_timeout(char *buffer, const struct kernel_param *kp)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 345) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 346) 	long num = *((int *)kp->arg);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 347) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 348) 	if (num > 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 349) 		if (num >= INT_MAX - (HZ - 1))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 350) 			num = INT_MAX / HZ;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 351) 		else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 352) 			num = (num + (HZ - 1)) / HZ;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 353) 	} else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 354) 		num = -1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 355) 	return scnprintf(buffer, PAGE_SIZE, "%li\n", num);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 356) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 357) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 358) static const struct kernel_param_ops param_ops_nfs_timeout = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 359) 	.set = param_set_nfs_timeout,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 360) 	.get = param_get_nfs_timeout,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 361) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 362) #define param_check_nfs_timeout(name, p) __param_check(name, p, int);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 363) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 364) module_param(nfs_mountpoint_expiry_timeout, nfs_timeout, 0644);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 365) MODULE_PARM_DESC(nfs_mountpoint_expiry_timeout,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 366) 		"Set the NFS automounted mountpoint timeout value (seconds)."
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 367) 		"Values <= 0 turn expiration off.");