fs/nfs/inode.c

/* */
This source file includes following definitions.
nfs_read_inode
nfs_put_inode
nfs_put_super
nfs_read_super
nfs_statfs
nfs_fhget
nfs_notify_change
run_nfsiod
init_nfs_fs
init_module
cleanup_module
   1 /*
   2  *  linux/fs/nfs/inode.c
   3  *
   4  *  Copyright (C) 1992  Rick Sladkey
   5  *
   6  *  nfs inode and superblock handling functions
   7  *
   8  *  Modularised by Alan Cox <Alan.Cox@linux.org>, while hacking some
   9  *  experimental NFS changes. Modularisation taken straight from SYS5 fs.
  10  *
  11  *  Change to nfs_read_super() to permit NFS mounts to multi-homed hosts.
  12  *  J.S.Peatfield@damtp.cam.ac.uk
  13  *
  14  */
  15 
  16 #include <linux/module.h>
  17 
  18 #include <linux/sched.h>
  19 #include <linux/nfs_fs.h>
  20 #include <linux/nfsiod.h>
  21 #include <linux/kernel.h>
  22 #include <linux/mm.h>
  23 #include <linux/string.h>
  24 #include <linux/stat.h>
  25 #include <linux/errno.h>
  26 #include <linux/locks.h>
  27 #include <linux/smp.h>
  28 #include <linux/smp_lock.h>
  29 
  30 #include <asm/system.h>
  31 #include <asm/segment.h>
  32 
  33 /* This is for kernel_thread */
  34 #define __KERNEL_SYSCALLS__
  35 #include <linux/unistd.h>
  36 
  37 extern int close_fp(struct file *filp);
  38 
  39 static int nfs_notify_change(struct inode *, struct iattr *);
  40 static void nfs_put_inode(struct inode *);
  41 static void nfs_put_super(struct super_block *);
  42 static void nfs_read_inode(struct inode *);
  43 static void nfs_statfs(struct super_block *, struct statfs *, int bufsiz);
  44 
  45 static struct super_operations nfs_sops = { 
  46         nfs_read_inode,         /* read inode */
  47         nfs_notify_change,      /* notify change */
  48         NULL,                   /* write inode */
  49         nfs_put_inode,          /* put inode */
  50         nfs_put_super,          /* put superblock */
  51         NULL,                   /* write superblock */
  52         nfs_statfs,             /* stat filesystem */
  53         NULL
  54 };
  55 
  56 /*
  57  * The "read_inode" function doesn't actually do anything:
  58  * the real data is filled in later in nfs_fhget. Here we
  59  * just mark the cache times invalid, and zero out i_mode
  60  * (the latter makes "nfs_refresh_inode" do the right thing
  61  * wrt pipe inodes)
  62  */
  63 static void nfs_read_inode(struct inode * inode)
     /*  */
  64 {
  65         int rsize = inode->i_sb->u.nfs_sb.s_server.rsize;
  66         int size = inode->i_sb->u.nfs_sb.s_server.wsize;
  67 
  68         if (rsize > size)
  69                 size = rsize;
  70         inode->i_blksize = size;
  71         inode->i_mode = 0;
  72         inode->i_op = NULL;
  73         NFS_CACHEINV(inode);
  74 }
  75 
  76 static void nfs_put_inode(struct inode * inode)
     /*  */
  77 {
  78         if (NFS_RENAMED_DIR(inode))
  79                 nfs_sillyrename_cleanup(inode);
  80         if (inode->i_pipe)
  81                 clear_inode(inode);
  82 }
  83 
  84 void nfs_put_super(struct super_block *sb)
     /*  */
  85 {
  86         close_fp(sb->u.nfs_sb.s_server.file);
  87         rpc_closesock(sb->u.nfs_sb.s_server.rsock);
  88         lock_super(sb);
  89         sb->s_dev = 0;
  90         unlock_super(sb);
  91         MOD_DEC_USE_COUNT;
  92 }
  93 
  94 /*
  95  * The way this works is that the mount process passes a structure
  96  * in the data argument which contains an open socket to the NFS
  97  * server and the root file handle obtained from the server's mount
  98  * daemon.  We stash these away in the private superblock fields.
  99  * Later we can add other mount parameters like caching values.
 100  */
 101 
 102 struct super_block *nfs_read_super(struct super_block *sb, void *raw_data,
     /*  */
 103                                    int silent)
 104 {
 105         struct nfs_mount_data *data = (struct nfs_mount_data *) raw_data;
 106         struct nfs_server *server;
 107         unsigned int fd;
 108         struct file *filp;
 109 
 110         kdev_t dev = sb->s_dev;
 111 
 112         MOD_INC_USE_COUNT;
 113         if (!data) {
 114                 printk("nfs_read_super: missing data argument\n");
 115                 sb->s_dev = 0;
 116                 MOD_DEC_USE_COUNT;
 117                 return NULL;
 118         }
 119         fd = data->fd;
 120         if (data->version != NFS_MOUNT_VERSION) {
 121                 printk("nfs warning: mount version %s than kernel\n",
 122                         data->version < NFS_MOUNT_VERSION ? "older" : "newer");
 123         }
 124         if (fd >= NR_OPEN || !(filp = current->files->fd[fd])) {
 125                 printk("nfs_read_super: invalid file descriptor\n");
 126                 sb->s_dev = 0;
 127                 MOD_DEC_USE_COUNT;
 128                 return NULL;
 129         }
 130         if (!S_ISSOCK(filp->f_inode->i_mode)) {
 131                 printk("nfs_read_super: not a socket\n");
 132                 sb->s_dev = 0;
 133                 MOD_DEC_USE_COUNT;
 134                 return NULL;
 135         }
 136         filp->f_count++;
 137         lock_super(sb);
 138 
 139         sb->s_blocksize = 1024; /* XXX */
 140         sb->s_blocksize_bits = 10;
 141         sb->s_magic = NFS_SUPER_MAGIC;
 142         sb->s_dev = dev;
 143         sb->s_op = &nfs_sops;
 144         server = &sb->u.nfs_sb.s_server;
 145         server->file = filp;
 146         server->lock = 0;
 147         server->wait = NULL;
 148         server->flags = data->flags;
 149         server->rsize = data->rsize;
 150         if (server->rsize <= 0)
 151                 server->rsize = NFS_DEF_FILE_IO_BUFFER_SIZE;
 152         else if (server->rsize >= NFS_MAX_FILE_IO_BUFFER_SIZE)
 153                 server->rsize = NFS_MAX_FILE_IO_BUFFER_SIZE;
 154         server->wsize = data->wsize;
 155         if (server->wsize <= 0)
 156                 server->wsize = NFS_DEF_FILE_IO_BUFFER_SIZE;
 157         else if (server->wsize >= NFS_MAX_FILE_IO_BUFFER_SIZE)
 158                 server->wsize = NFS_MAX_FILE_IO_BUFFER_SIZE;
 159         server->timeo = data->timeo*HZ/10;
 160         server->retrans = data->retrans;
 161         server->acregmin = data->acregmin*HZ;
 162         server->acregmax = data->acregmax*HZ;
 163         server->acdirmin = data->acdirmin*HZ;
 164         server->acdirmax = data->acdirmax*HZ;
 165         strcpy(server->hostname, data->hostname);
 166 
 167         /* Start of JSP NFS patch */
 168         /* Check if passed address in data->addr */
 169         if (data->addr.sin_addr.s_addr == INADDR_ANY) {  /* No address passed */
 170           if (((struct sockaddr_in *)(&server->toaddr))->sin_addr.s_addr == INADDR_ANY) {
 171             printk("NFS: Error passed unconnected socket and no address\n") ;
 172             MOD_DEC_USE_COUNT;
 173             return NULL ;
 174           } else {
 175             /* Need access to socket internals  JSP */
 176             struct socket *sock;
 177             int dummylen ;
 178 
 179          /*   printk("NFS: using socket address\n") ;*/
 180 
 181             sock = &((filp->f_inode)->u.socket_i);
 182 
 183             /* extract the other end of the socket into server->toaddr */
 184             sock->ops->getname(sock, &(server->toaddr), &dummylen, 1) ;
 185           }
 186         } else {
 187         /*  printk("NFS: copying passed addr to server->toaddr\n") ;*/
 188           memcpy((char *)&(server->toaddr),(char *)(&data->addr),sizeof(server->toaddr));
 189         }
 190         /* End of JSP NFS patch */
 191 
 192         if ((server->rsock = rpc_makesock(filp)) == NULL) {
 193                 printk("NFS: cannot create RPC socket.\n");
 194                 MOD_DEC_USE_COUNT;
 195                 return NULL;
 196         }
 197 
 198         sb->u.nfs_sb.s_root = data->root;
 199         unlock_super(sb);
 200         if (!(sb->s_mounted = nfs_fhget(sb, &data->root, NULL))) {
 201                 sb->s_dev = 0;
 202                 printk("nfs_read_super: get root inode failed\n");
 203                 MOD_DEC_USE_COUNT;
 204                 return NULL;
 205         }
 206         return sb;
 207 }
 208 
 209 void nfs_statfs(struct super_block *sb, struct statfs *buf, int bufsiz)
     /*  */
 210 {
 211         int error;
 212         struct nfs_fsinfo res;
 213         struct statfs tmp;
 214 
 215         error = nfs_proc_statfs(&sb->u.nfs_sb.s_server, &sb->u.nfs_sb.s_root,
 216                 &res);
 217         if (error) {
 218                 printk("nfs_statfs: statfs error = %d\n", -error);
 219                 res.bsize = res.blocks = res.bfree = res.bavail = 0;
 220         }
 221         tmp.f_type = NFS_SUPER_MAGIC;
 222         tmp.f_bsize = res.bsize;
 223         tmp.f_blocks = res.blocks;
 224         tmp.f_bfree = res.bfree;
 225         tmp.f_bavail = res.bavail;
 226         tmp.f_files = 0;
 227         tmp.f_ffree = 0;
 228         tmp.f_namelen = NAME_MAX;
 229         memcpy_tofs(buf, &tmp, bufsiz);
 230 }
 231 
 232 /*
 233  * This is our own version of iget that looks up inodes by file handle
 234  * instead of inode number.  We use this technique instead of using
 235  * the vfs read_inode function because there is no way to pass the
 236  * file handle or current attributes into the read_inode function.
 237  * We just have to be careful not to subvert iget's special handling
 238  * of mount points.
 239  */
 240 
 241 struct inode *nfs_fhget(struct super_block *sb, struct nfs_fh *fhandle,
     /*  */
 242                         struct nfs_fattr *fattr)
 243 {
 244         struct nfs_fattr newfattr;
 245         int error;
 246         struct inode *inode;
 247 
 248         if (!sb) {
 249                 printk("nfs_fhget: super block is NULL\n");
 250                 return NULL;
 251         }
 252         if (!fattr) {
 253                 error = nfs_proc_getattr(&sb->u.nfs_sb.s_server, fhandle,
 254                         &newfattr);
 255                 if (error) {
 256                         printk("nfs_fhget: getattr error = %d\n", -error);
 257                         return NULL;
 258                 }
 259                 fattr = &newfattr;
 260         }
 261         if (!(inode = iget(sb, fattr->fileid))) {
 262                 printk("nfs_fhget: iget failed\n");
 263                 return NULL;
 264         }
 265         if (inode->i_dev == sb->s_dev) {
 266                 if (inode->i_ino != fattr->fileid) {
 267                         printk("nfs_fhget: unexpected inode from iget\n");
 268                         return inode;
 269                 }
 270                 *NFS_FH(inode) = *fhandle;
 271                 nfs_refresh_inode(inode, fattr);
 272         }
 273         return inode;
 274 }
 275 
 276 int nfs_notify_change(struct inode *inode, struct iattr *attr)
     /*  */
 277 {
 278         struct nfs_sattr sattr;
 279         struct nfs_fattr fattr;
 280         int error;
 281 
 282         sattr.mode = (unsigned) -1;
 283         if (attr->ia_valid & ATTR_MODE) 
 284                 sattr.mode = attr->ia_mode;
 285 
 286         sattr.uid = (unsigned) -1;
 287         if (attr->ia_valid & ATTR_UID)
 288                 sattr.uid = attr->ia_uid;
 289 
 290         sattr.gid = (unsigned) -1;
 291         if (attr->ia_valid & ATTR_GID)
 292                 sattr.gid = attr->ia_gid;
 293 
 294 
 295         sattr.size = (unsigned) -1;
 296         if (attr->ia_valid & ATTR_SIZE)
 297                 sattr.size = S_ISREG(inode->i_mode) ? attr->ia_size : -1;
 298 
 299         sattr.mtime.seconds = sattr.mtime.useconds = (unsigned) -1;
 300         if (attr->ia_valid & ATTR_MTIME) {
 301                 sattr.mtime.seconds = attr->ia_mtime;
 302                 sattr.mtime.useconds = 0;
 303         }
 304 
 305         sattr.atime.seconds = sattr.atime.useconds = (unsigned) -1;
 306         if (attr->ia_valid & ATTR_ATIME) {
 307                 sattr.atime.seconds = attr->ia_atime;
 308                 sattr.atime.useconds = 0;
 309         }
 310 
 311         error = nfs_proc_setattr(NFS_SERVER(inode), NFS_FH(inode),
 312                 &sattr, &fattr);
 313         if (!error)
 314                 nfs_refresh_inode(inode, &fattr);
 315         inode->i_dirt = 0;
 316         return error;
 317 }
 318 
 319 /* Every kernel module contains stuff like this. */
 320 
 321 static struct file_system_type nfs_fs_type = {
 322         nfs_read_super, "nfs", 0, NULL
 323 };
 324 
 325 /*
 326  * Start up an nfsiod process. This is an awful hack, because when running
 327  * as a module, we will keep insmod's memory. Besides, the current->comm
 328  * hack won't work in this case
 329  * The best would be to have a syscall for nfs client control that (among
 330  * other things) forks biod's.
 331  * Alternatively, we might want to have the idle task spawn biod's on demand.
 332  */
 333 static int run_nfsiod(void *dummy)
     /*  */
 334 {
 335         int     ret;
 336 
 337 #ifdef __SMP__
 338         lock_kernel();
 339         syscall_count++;
 340 #endif
 341 
 342         MOD_INC_USE_COUNT;
 343         current->session = 1;
 344         current->pgrp = 1;
 345         sprintf(current->comm, "nfsiod");
 346         ret = nfsiod();
 347         MOD_DEC_USE_COUNT;
 348         return ret;
 349 }
 350 
 351 int init_nfs_fs(void)
     /*  */
 352 {
 353         /* Fork four biod's */
 354         kernel_thread(run_nfsiod, NULL, 0);
 355         kernel_thread(run_nfsiod, NULL, 0);
 356         kernel_thread(run_nfsiod, NULL, 0);
 357         kernel_thread(run_nfsiod, NULL, 0);
 358         return register_filesystem(&nfs_fs_type);
 359 }
 360 
 361 #ifdef MODULE
 362 int init_module(void)
     /*  */
 363 {
 364         int status;
 365 
 366         if ((status = init_nfs_fs()) == 0)
 367                 register_symtab(0);
 368         return status;
 369 }
 370 
 371 void cleanup_module(void)
     /*  */
 372 {
 373         unregister_filesystem(&nfs_fs_type);
 374         nfs_kfree_cache();
 375 }
 376 
 377 #endif
/* */
root/fs/nfs/inode.c

DEFINITIONS
