inode.c
上传用户:lgb322
上传日期:2013-02-24
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文件大小:31k
- /*
- * linux/fs/nfs/inode.c
- *
- * Copyright (C) 1992 Rick Sladkey
- *
- * nfs inode and 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
- *
- */
- #include <linux/config.h>
- #include <linux/module.h>
- #include <linux/init.h>
- #include <linux/sched.h>
- #include <linux/kernel.h>
- #include <linux/mm.h>
- #include <linux/string.h>
- #include <linux/stat.h>
- #include <linux/errno.h>
- #include <linux/locks.h>
- #include <linux/unistd.h>
- #include <linux/sunrpc/clnt.h>
- #include <linux/sunrpc/stats.h>
- #include <linux/nfs_fs.h>
- #include <linux/nfs_mount.h>
- #include <linux/nfs_flushd.h>
- #include <linux/lockd/bind.h>
- #include <linux/smp_lock.h>
- #include <linux/seq_file.h>
- #include <asm/system.h>
- #include <asm/uaccess.h>
- #define CONFIG_NFS_SNAPSHOT 1
- #define NFSDBG_FACILITY NFSDBG_VFS
- #define NFS_PARANOIA 1
- static struct inode * __nfs_fhget(struct super_block *, struct nfs_fh *, struct nfs_fattr *);
- void nfs_zap_caches(struct inode *);
- static void nfs_invalidate_inode(struct inode *);
- static void nfs_read_inode(struct inode *);
- static void nfs_write_inode(struct inode *,int);
- static void nfs_delete_inode(struct inode *);
- static void nfs_put_super(struct super_block *);
- static void nfs_clear_inode(struct inode *);
- static void nfs_umount_begin(struct super_block *);
- static int nfs_statfs(struct super_block *, struct statfs *);
- static int nfs_show_options(struct seq_file *, struct vfsmount *);
- static struct super_operations nfs_sops = {
- read_inode: nfs_read_inode,
- write_inode: nfs_write_inode,
- delete_inode: nfs_delete_inode,
- put_super: nfs_put_super,
- statfs: nfs_statfs,
- clear_inode: nfs_clear_inode,
- umount_begin: nfs_umount_begin,
- show_options: nfs_show_options,
- };
- /*
- * RPC cruft for NFS
- */
- struct rpc_stat nfs_rpcstat = { &nfs_program };
- static struct rpc_version * nfs_version[] = {
- NULL,
- NULL,
- &nfs_version2,
- #ifdef CONFIG_NFS_V3
- &nfs_version3,
- #endif
- };
- struct rpc_program nfs_program = {
- "nfs",
- NFS_PROGRAM,
- sizeof(nfs_version) / sizeof(nfs_version[0]),
- nfs_version,
- &nfs_rpcstat,
- };
- static inline unsigned long
- nfs_fattr_to_ino_t(struct nfs_fattr *fattr)
- {
- return nfs_fileid_to_ino_t(fattr->fileid);
- }
- /*
- * The "read_inode" function doesn't actually do anything:
- * the real data is filled in later in nfs_fhget. Here we
- * just mark the cache times invalid, and zero out i_mode
- * (the latter makes "nfs_refresh_inode" do the right thing
- * wrt pipe inodes)
- */
- static void
- nfs_read_inode(struct inode * inode)
- {
- inode->i_blksize = inode->i_sb->s_blocksize;
- inode->i_mode = 0;
- inode->i_rdev = 0;
- /* We can't support UPDATE_ATIME(), since the server will reset it */
- inode->i_flags |= S_NOATIME;
- INIT_LIST_HEAD(&inode->u.nfs_i.read);
- INIT_LIST_HEAD(&inode->u.nfs_i.dirty);
- INIT_LIST_HEAD(&inode->u.nfs_i.commit);
- INIT_LIST_HEAD(&inode->u.nfs_i.writeback);
- NFS_CACHEINV(inode);
- NFS_ATTRTIMEO(inode) = NFS_MINATTRTIMEO(inode);
- NFS_ATTRTIMEO_UPDATE(inode) = jiffies;
- }
- static void
- nfs_write_inode(struct inode *inode, int sync)
- {
- int flags = sync ? FLUSH_WAIT : 0;
- nfs_sync_file(inode, NULL, 0, 0, flags);
- }
- static void
- nfs_delete_inode(struct inode * inode)
- {
- dprintk("NFS: delete_inode(%x/%ld)n", inode->i_dev, inode->i_ino);
- /*
- * The following can never actually happen...
- */
- if (nfs_have_writebacks(inode) || nfs_have_read(inode)) {
- printk(KERN_ERR "nfs_delete_inode: inode %ld has pending RPC requestsn", inode->i_ino);
- }
- clear_inode(inode);
- }
- /*
- * For the moment, the only task for the NFS clear_inode method is to
- * release the mmap credential
- */
- static void
- nfs_clear_inode(struct inode *inode)
- {
- struct rpc_cred *cred = NFS_I(inode)->mm_cred;
- if (cred)
- put_rpccred(cred);
- }
- void
- nfs_put_super(struct super_block *sb)
- {
- struct nfs_server *server = &sb->u.nfs_sb.s_server;
- struct rpc_clnt *rpc;
- /*
- * First get rid of the request flushing daemon.
- * Relies on rpc_shutdown_client() waiting on all
- * client tasks to finish.
- */
- nfs_reqlist_exit(server);
- if ((rpc = server->client) != NULL)
- rpc_shutdown_client(rpc);
- nfs_reqlist_free(server);
- if (!(server->flags & NFS_MOUNT_NONLM))
- lockd_down(); /* release rpc.lockd */
- rpciod_down(); /* release rpciod */
- kfree(server->hostname);
- }
- void
- nfs_umount_begin(struct super_block *sb)
- {
- struct nfs_server *server = &sb->u.nfs_sb.s_server;
- struct rpc_clnt *rpc;
- /* -EIO all pending I/O */
- if ((rpc = server->client) != NULL)
- rpc_killall_tasks(rpc);
- }
- static inline unsigned long
- nfs_block_bits(unsigned long bsize, unsigned char *nrbitsp)
- {
- /* make sure blocksize is a power of two */
- if ((bsize & (bsize - 1)) || nrbitsp) {
- unsigned char nrbits;
- for (nrbits = 31; nrbits && !(bsize & (1 << nrbits)); nrbits--)
- ;
- bsize = 1 << nrbits;
- if (nrbitsp)
- *nrbitsp = nrbits;
- }
- return bsize;
- }
- /*
- * Calculate the number of 512byte blocks used.
- */
- static inline unsigned long
- nfs_calc_block_size(u64 tsize)
- {
- loff_t used = (tsize + 511) >> 9;
- return (used > ULONG_MAX) ? ULONG_MAX : used;
- }
- /*
- * Compute and set NFS server blocksize
- */
- static inline unsigned long
- nfs_block_size(unsigned long bsize, unsigned char *nrbitsp)
- {
- if (bsize < 1024)
- bsize = NFS_DEF_FILE_IO_BUFFER_SIZE;
- else if (bsize >= NFS_MAX_FILE_IO_BUFFER_SIZE)
- bsize = NFS_MAX_FILE_IO_BUFFER_SIZE;
- return nfs_block_bits(bsize, nrbitsp);
- }
- /*
- * Obtain the root inode of the file system.
- */
- static struct inode *
- nfs_get_root(struct super_block *sb, struct nfs_fh *rootfh)
- {
- struct nfs_server *server = &sb->u.nfs_sb.s_server;
- struct nfs_fattr fattr;
- struct inode *inode;
- int error;
- if ((error = server->rpc_ops->getroot(server, rootfh, &fattr)) < 0) {
- printk(KERN_NOTICE "nfs_get_root: getattr error = %dn", -error);
- return NULL;
- }
- inode = __nfs_fhget(sb, rootfh, &fattr);
- return inode;
- }
- /*
- * The way this works is that the mount process passes a structure
- * in the data argument which contains the server's IP address
- * and the root file handle obtained from the server's mount
- * daemon. We stash these away in the private superblock fields.
- */
- struct super_block *
- nfs_read_super(struct super_block *sb, void *raw_data, int silent)
- {
- struct nfs_mount_data *data = (struct nfs_mount_data *) raw_data;
- struct nfs_server *server;
- struct rpc_xprt *xprt = NULL;
- struct rpc_clnt *clnt = NULL;
- struct nfs_fh *root = &data->root, fh;
- struct inode *root_inode = NULL;
- unsigned int authflavor;
- struct sockaddr_in srvaddr;
- struct rpc_timeout timeparms;
- struct nfs_fsinfo fsinfo;
- int tcp, version, maxlen;
- memset(&sb->u.nfs_sb, 0, sizeof(sb->u.nfs_sb));
- if (!data)
- goto out_miss_args;
- memset(&fh, 0, sizeof(fh));
- if (data->version != NFS_MOUNT_VERSION) {
- printk("nfs warning: mount version %s than kerneln",
- data->version < NFS_MOUNT_VERSION ? "older" : "newer");
- if (data->version < 2)
- data->namlen = 0;
- if (data->version < 3)
- data->bsize = 0;
- if (data->version < 4) {
- data->flags &= ~NFS_MOUNT_VER3;
- root = &fh;
- root->size = NFS2_FHSIZE;
- memcpy(root->data, data->old_root.data, NFS2_FHSIZE);
- }
- }
- /* We now require that the mount process passes the remote address */
- memcpy(&srvaddr, &data->addr, sizeof(srvaddr));
- if (srvaddr.sin_addr.s_addr == INADDR_ANY)
- goto out_no_remote;
- sb->s_magic = NFS_SUPER_MAGIC;
- sb->s_op = &nfs_sops;
- sb->s_blocksize_bits = 0;
- sb->s_blocksize = nfs_block_size(data->bsize, &sb->s_blocksize_bits);
- server = &sb->u.nfs_sb.s_server;
- server->rsize = nfs_block_size(data->rsize, NULL);
- server->wsize = nfs_block_size(data->wsize, NULL);
- server->flags = data->flags & NFS_MOUNT_FLAGMASK;
- if (data->flags & NFS_MOUNT_NOAC) {
- data->acregmin = data->acregmax = 0;
- data->acdirmin = data->acdirmax = 0;
- sb->s_flags |= MS_SYNCHRONOUS;
- }
- server->acregmin = data->acregmin*HZ;
- server->acregmax = data->acregmax*HZ;
- server->acdirmin = data->acdirmin*HZ;
- server->acdirmax = data->acdirmax*HZ;
- server->namelen = data->namlen;
- server->hostname = kmalloc(strlen(data->hostname) + 1, GFP_KERNEL);
- if (!server->hostname)
- goto out_unlock;
- strcpy(server->hostname, data->hostname);
- INIT_LIST_HEAD(&server->lru_read);
- INIT_LIST_HEAD(&server->lru_dirty);
- INIT_LIST_HEAD(&server->lru_commit);
- INIT_LIST_HEAD(&server->lru_busy);
- nfsv3_try_again:
- /* Check NFS protocol revision and initialize RPC op vector
- * and file handle pool. */
- if (data->flags & NFS_MOUNT_VER3) {
- #ifdef CONFIG_NFS_V3
- server->rpc_ops = &nfs_v3_clientops;
- version = 3;
- if (data->version < 4) {
- printk(KERN_NOTICE "NFS: NFSv3 not supported by mount program.n");
- goto out_unlock;
- }
- #else
- printk(KERN_NOTICE "NFS: NFSv3 not supported.n");
- goto out_unlock;
- #endif
- } else {
- server->rpc_ops = &nfs_v2_clientops;
- version = 2;
- }
- /* Which protocol do we use? */
- tcp = (data->flags & NFS_MOUNT_TCP);
- /* Initialize timeout values */
- timeparms.to_initval = data->timeo * HZ / 10;
- timeparms.to_retries = data->retrans;
- timeparms.to_maxval = tcp? RPC_MAX_TCP_TIMEOUT : RPC_MAX_UDP_TIMEOUT;
- timeparms.to_exponential = 1;
- if (!timeparms.to_initval)
- timeparms.to_initval = (tcp ? 600 : 11) * HZ / 10;
- if (!timeparms.to_retries)
- timeparms.to_retries = 5;
- /* Now create transport and client */
- xprt = xprt_create_proto(tcp? IPPROTO_TCP : IPPROTO_UDP,
- &srvaddr, &timeparms);
- if (xprt == NULL)
- goto out_no_xprt;
- /* Choose authentication flavor */
- authflavor = RPC_AUTH_UNIX;
- if (data->flags & NFS_MOUNT_SECURE)
- authflavor = RPC_AUTH_DES;
- else if (data->flags & NFS_MOUNT_KERBEROS)
- authflavor = RPC_AUTH_KRB;
- clnt = rpc_create_client(xprt, server->hostname, &nfs_program,
- version, authflavor);
- if (clnt == NULL)
- goto out_no_client;
- clnt->cl_intr = (data->flags & NFS_MOUNT_INTR)? 1 : 0;
- clnt->cl_softrtry = (data->flags & NFS_MOUNT_SOFT)? 1 : 0;
- clnt->cl_droppriv = (data->flags & NFS_MOUNT_BROKEN_SUID) ? 1 : 0;
- clnt->cl_chatty = 1;
- server->client = clnt;
- /* Fire up rpciod if not yet running */
- if (rpciod_up() != 0)
- goto out_no_iod;
- /*
- * Keep the super block locked while we try to get
- * the root fh attributes.
- */
- /* Did getting the root inode fail? */
- if (!(root_inode = nfs_get_root(sb, root))
- && (data->flags & NFS_MOUNT_VER3)) {
- data->flags &= ~NFS_MOUNT_VER3;
- rpciod_down();
- rpc_shutdown_client(server->client);
- goto nfsv3_try_again;
- }
- if (!root_inode)
- goto out_no_root;
- sb->s_root = d_alloc_root(root_inode);
- if (!sb->s_root)
- goto out_no_root;
- sb->s_root->d_op = &nfs_dentry_operations;
- /* Get some general file system info */
- if (server->rpc_ops->statfs(server, root, &fsinfo) >= 0) {
- if (server->namelen == 0)
- server->namelen = fsinfo.namelen;
- } else {
- printk(KERN_NOTICE "NFS: cannot retrieve file system info.n");
- goto out_no_root;
- }
- /* Work out a lot of parameters */
- if (data->rsize == 0)
- server->rsize = nfs_block_size(fsinfo.rtpref, NULL);
- if (data->wsize == 0)
- server->wsize = nfs_block_size(fsinfo.wtpref, NULL);
- /* NFSv3: we don't have bsize, but rather rtmult and wtmult... */
- if (!fsinfo.bsize)
- fsinfo.bsize = (fsinfo.rtmult>fsinfo.wtmult) ? fsinfo.rtmult : fsinfo.wtmult;
- /* Also make sure we don't go below rsize/wsize since
- * RPC calls are expensive */
- if (fsinfo.bsize < server->rsize)
- fsinfo.bsize = server->rsize;
- if (fsinfo.bsize < server->wsize)
- fsinfo.bsize = server->wsize;
- if (data->bsize == 0)
- sb->s_blocksize = nfs_block_bits(fsinfo.bsize, &sb->s_blocksize_bits);
- if (server->rsize > fsinfo.rtmax)
- server->rsize = fsinfo.rtmax;
- if (server->wsize > fsinfo.wtmax)
- server->wsize = fsinfo.wtmax;
- server->rpages = (server->rsize + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
- if (server->rpages > NFS_READ_MAXIOV) {
- server->rpages = NFS_READ_MAXIOV;
- server->rsize = server->rpages << PAGE_CACHE_SHIFT;
- }
- server->wpages = (server->wsize + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
- if (server->wpages > NFS_WRITE_MAXIOV) {
- server->wpages = NFS_WRITE_MAXIOV;
- server->wsize = server->wpages << PAGE_CACHE_SHIFT;
- }
- server->dtsize = nfs_block_size(fsinfo.dtpref, NULL);
- if (server->dtsize > PAGE_CACHE_SIZE)
- server->dtsize = PAGE_CACHE_SIZE;
- if (server->dtsize > server->rsize)
- server->dtsize = server->rsize;
- maxlen = (version == 2) ? NFS2_MAXNAMLEN : NFS3_MAXNAMLEN;
- if (server->namelen == 0 || server->namelen > maxlen)
- server->namelen = maxlen;
- sb->s_maxbytes = fsinfo.maxfilesize;
- /* Fire up the writeback cache */
- if (nfs_reqlist_alloc(server) < 0) {
- printk(KERN_NOTICE "NFS: cannot initialize writeback cache.n");
- goto failure_kill_reqlist;
- }
- /* We're airborne */
- /* Check whether to start the lockd process */
- if (!(server->flags & NFS_MOUNT_NONLM))
- lockd_up();
- return sb;
- /* Yargs. It didn't work out. */
- failure_kill_reqlist:
- nfs_reqlist_exit(server);
- out_no_root:
- printk("nfs_read_super: get root inode failedn");
- iput(root_inode);
- rpciod_down();
- goto out_shutdown;
- out_no_iod:
- printk(KERN_WARNING "NFS: couldn't start rpciod!n");
- out_shutdown:
- rpc_shutdown_client(server->client);
- goto out_free_host;
- out_no_client:
- printk(KERN_WARNING "NFS: cannot create RPC client.n");
- xprt_destroy(xprt);
- goto out_free_host;
- out_no_xprt:
- printk(KERN_WARNING "NFS: cannot create RPC transport.n");
- out_free_host:
- nfs_reqlist_free(server);
- kfree(server->hostname);
- out_unlock:
- goto out_fail;
- out_no_remote:
- printk("NFS: mount program didn't pass remote address!n");
- goto out_fail;
- out_miss_args:
- printk("nfs_read_super: missing data argumentn");
- out_fail:
- return NULL;
- }
- static int
- nfs_statfs(struct super_block *sb, struct statfs *buf)
- {
- struct nfs_server *server = &sb->u.nfs_sb.s_server;
- unsigned char blockbits;
- unsigned long blockres;
- struct nfs_fsinfo res;
- int error;
- error = server->rpc_ops->statfs(server, NFS_FH(sb->s_root->d_inode), &res);
- buf->f_type = NFS_SUPER_MAGIC;
- if (error < 0)
- goto out_err;
- if (res.bsize == 0)
- res.bsize = sb->s_blocksize;
- buf->f_bsize = nfs_block_bits(res.bsize, &blockbits);
- 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;
- if (res.namelen == 0 || res.namelen > server->namelen)
- res.namelen = server->namelen;
- buf->f_namelen = res.namelen;
- return 0;
- out_err:
- printk("nfs_statfs: statfs error = %dn", -error);
- buf->f_bsize = buf->f_blocks = buf->f_bfree = buf->f_bavail = -1;
- return 0;
- }
- static int nfs_show_options(struct seq_file *m, struct vfsmount *mnt)
- {
- static struct proc_nfs_info {
- int flag;
- char *str;
- char *nostr;
- } nfs_info[] = {
- { NFS_MOUNT_SOFT, ",soft", ",hard" },
- { NFS_MOUNT_INTR, ",intr", "" },
- { NFS_MOUNT_POSIX, ",posix", "" },
- { NFS_MOUNT_TCP, ",tcp", ",udp" },
- { NFS_MOUNT_NOCTO, ",nocto", "" },
- { NFS_MOUNT_NOAC, ",noac", "" },
- { NFS_MOUNT_NONLM, ",nolock", ",lock" },
- { NFS_MOUNT_BROKEN_SUID, ",broken_suid", "" },
- { 0, NULL, NULL }
- };
- struct proc_nfs_info *nfs_infop;
- struct nfs_server *nfss = &mnt->mnt_sb->u.nfs_sb.s_server;
- seq_printf(m, ",v%d", nfss->rpc_ops->version);
- seq_printf(m, ",rsize=%d", nfss->rsize);
- seq_printf(m, ",wsize=%d", nfss->wsize);
- if (nfss->acregmin != 3*HZ)
- seq_printf(m, ",acregmin=%d", nfss->acregmin/HZ);
- if (nfss->acregmax != 60*HZ)
- seq_printf(m, ",acregmax=%d", nfss->acregmax/HZ);
- if (nfss->acdirmin != 30*HZ)
- seq_printf(m, ",acdirmin=%d", nfss->acdirmin/HZ);
- if (nfss->acdirmax != 60*HZ)
- 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);
- }
- seq_puts(m, ",addr=");
- seq_escape(m, nfss->hostname, " tn\");
- return 0;
- }
- /*
- * Invalidate the local caches
- */
- void
- nfs_zap_caches(struct inode *inode)
- {
- NFS_ATTRTIMEO(inode) = NFS_MINATTRTIMEO(inode);
- NFS_ATTRTIMEO_UPDATE(inode) = jiffies;
- invalidate_inode_pages(inode);
- memset(NFS_COOKIEVERF(inode), 0, sizeof(NFS_COOKIEVERF(inode)));
- NFS_CACHEINV(inode);
- }
- /*
- * Invalidate, but do not unhash, the inode
- */
- static void
- nfs_invalidate_inode(struct inode *inode)
- {
- umode_t save_mode = inode->i_mode;
- make_bad_inode(inode);
- inode->i_mode = save_mode;
- nfs_zap_caches(inode);
- }
- /*
- * Fill in inode information from the fattr.
- */
- static void
- nfs_fill_inode(struct inode *inode, struct nfs_fh *fh, struct nfs_fattr *fattr)
- {
- /*
- * Check whether the mode has been set, as we only want to
- * do this once. (We don't allow inodes to change types.)
- */
- if (inode->i_mode == 0) {
- NFS_FILEID(inode) = fattr->fileid;
- NFS_FSID(inode) = fattr->fsid;
- inode->i_mode = fattr->mode;
- /* Why so? Because we want revalidate for devices/FIFOs, and
- * that's precisely what we have in nfs_file_inode_operations.
- */
- inode->i_op = &nfs_file_inode_operations;
- if (S_ISREG(inode->i_mode)) {
- inode->i_fop = &nfs_file_operations;
- inode->i_data.a_ops = &nfs_file_aops;
- } else if (S_ISDIR(inode->i_mode)) {
- inode->i_op = &nfs_dir_inode_operations;
- inode->i_fop = &nfs_dir_operations;
- } else if (S_ISLNK(inode->i_mode))
- inode->i_op = &nfs_symlink_inode_operations;
- else
- init_special_inode(inode, inode->i_mode, fattr->rdev);
- memcpy(&inode->u.nfs_i.fh, fh, sizeof(inode->u.nfs_i.fh));
- }
- nfs_refresh_inode(inode, fattr);
- }
- struct nfs_find_desc {
- struct nfs_fh *fh;
- struct nfs_fattr *fattr;
- };
- /*
- * In NFSv3 we can have 64bit inode numbers. In order to support
- * this, and re-exported directories (also seen in NFSv2)
- * we are forced to allow 2 different inodes to have the same
- * i_ino.
- */
- static int
- nfs_find_actor(struct inode *inode, unsigned long ino, void *opaque)
- {
- struct nfs_find_desc *desc = (struct nfs_find_desc *)opaque;
- struct nfs_fh *fh = desc->fh;
- struct nfs_fattr *fattr = desc->fattr;
- if (NFS_FSID(inode) != fattr->fsid)
- return 0;
- if (NFS_FILEID(inode) != fattr->fileid)
- return 0;
- if (memcmp(&inode->u.nfs_i.fh, fh, sizeof(inode->u.nfs_i.fh)) != 0)
- return 0;
- /* Force an attribute cache update if inode->i_count == 0 */
- if (!atomic_read(&inode->i_count))
- NFS_CACHEINV(inode);
- return 1;
- }
- int
- nfs_inode_is_stale(struct inode *inode, struct nfs_fh *fh, struct nfs_fattr *fattr)
- {
- /* Empty inodes are not stale */
- if (!inode->i_mode)
- return 0;
- if ((fattr->mode & S_IFMT) != (inode->i_mode & S_IFMT))
- return 1;
- if (is_bad_inode(inode) || NFS_STALE(inode))
- return 1;
- /* Has the filehandle changed? If so is the old one stale? */
- if (memcmp(&inode->u.nfs_i.fh, fh, sizeof(inode->u.nfs_i.fh)) != 0 &&
- __nfs_revalidate_inode(NFS_SERVER(inode),inode) == -ESTALE)
- return 1;
- return 0;
- }
- /*
- * This is our own version of iget that looks up inodes by file handle
- * instead of inode number. We use this technique instead of using
- * the vfs read_inode function because there is no way to pass the
- * file handle or current attributes into the read_inode function.
- *
- */
- struct inode *
- nfs_fhget(struct dentry *dentry, struct nfs_fh *fhandle,
- struct nfs_fattr *fattr)
- {
- struct super_block *sb = dentry->d_sb;
- dprintk("NFS: nfs_fhget(%s/%s fileid=%Ld)n",
- dentry->d_parent->d_name.name, dentry->d_name.name,
- (long long)fattr->fileid);
- return __nfs_fhget(sb, fhandle, fattr);
- }
- /*
- * Look up the inode by super block and fattr->fileid.
- */
- static struct inode *
- __nfs_fhget(struct super_block *sb, struct nfs_fh *fh, struct nfs_fattr *fattr)
- {
- struct nfs_find_desc desc = { fh, fattr };
- struct inode *inode = NULL;
- unsigned long ino;
- if ((fattr->valid & NFS_ATTR_FATTR) == 0)
- goto out_no_inode;
- if (!fattr->nlink) {
- printk("NFS: Buggy server - nlink == 0!n");
- goto out_no_inode;
- }
- ino = nfs_fattr_to_ino_t(fattr);
- if (!(inode = iget4(sb, ino, nfs_find_actor, &desc)))
- goto out_no_inode;
- nfs_fill_inode(inode, fh, fattr);
- dprintk("NFS: __nfs_fhget(%x/%Ld ct=%d)n",
- inode->i_dev, (long long)NFS_FILEID(inode),
- atomic_read(&inode->i_count));
- out:
- return inode;
- out_no_inode:
- printk("__nfs_fhget: iget failedn");
- goto out;
- }
- int
- nfs_notify_change(struct dentry *dentry, struct iattr *attr)
- {
- struct inode *inode = dentry->d_inode;
- struct nfs_fattr fattr;
- int error;
- /*
- * Make sure the inode is up-to-date.
- */
- error = nfs_revalidate(dentry);
- if (error) {
- #ifdef NFS_PARANOIA
- printk("nfs_notify_change: revalidate failed, error=%dn", error);
- #endif
- goto out;
- }
- if (!S_ISREG(inode->i_mode))
- attr->ia_valid &= ~ATTR_SIZE;
- filemap_fdatasync(inode->i_mapping);
- error = nfs_wb_all(inode);
- filemap_fdatawait(inode->i_mapping);
- if (error)
- goto out;
- error = NFS_PROTO(inode)->setattr(inode, &fattr, attr);
- if (error)
- goto out;
- /*
- * If we changed the size or mtime, update the inode
- * now to avoid invalidating the page cache.
- */
- if (attr->ia_valid & ATTR_SIZE) {
- if (attr->ia_size != fattr.size)
- printk("nfs_notify_change: attr=%Ld, fattr=%Ld??n",
- (long long) attr->ia_size, (long long)fattr.size);
- vmtruncate(inode, attr->ia_size);
- }
- /*
- * If we changed the size or mtime, update the inode
- * now to avoid invalidating the page cache.
- */
- if (!(fattr.valid & NFS_ATTR_WCC)) {
- fattr.pre_size = NFS_CACHE_ISIZE(inode);
- fattr.pre_mtime = NFS_CACHE_MTIME(inode);
- fattr.pre_ctime = NFS_CACHE_CTIME(inode);
- fattr.valid |= NFS_ATTR_WCC;
- }
- /* Force an attribute cache update */
- NFS_CACHEINV(inode);
- error = nfs_refresh_inode(inode, &fattr);
- out:
- return error;
- }
- /*
- * Wait for the inode to get unlocked.
- * (Used for NFS_INO_LOCKED and NFS_INO_REVALIDATING).
- */
- int
- nfs_wait_on_inode(struct inode *inode, int flag)
- {
- struct rpc_clnt *clnt = NFS_CLIENT(inode);
- int error;
- if (!(NFS_FLAGS(inode) & flag))
- return 0;
- atomic_inc(&inode->i_count);
- error = nfs_wait_event(clnt, inode->i_wait, !(NFS_FLAGS(inode) & flag));
- iput(inode);
- return error;
- }
- /*
- * Externally visible revalidation function
- */
- int
- nfs_revalidate(struct dentry *dentry)
- {
- struct inode *inode = dentry->d_inode;
- return nfs_revalidate_inode(NFS_SERVER(inode), inode);
- }
- /*
- * Ensure that mmap has a recent RPC credential for use when writing out
- * shared pages
- */
- static inline void
- nfs_set_mmcred(struct inode *inode, struct rpc_cred *cred)
- {
- struct rpc_cred **p = &NFS_I(inode)->mm_cred,
- *oldcred = *p;
- *p = get_rpccred(cred);
- if (oldcred)
- put_rpccred(oldcred);
- }
- /*
- * These are probably going to contain hooks for
- * allocating and releasing RPC credentials for
- * the file. I'll have to think about Tronds patch
- * a bit more..
- */
- int nfs_open(struct inode *inode, struct file *filp)
- {
- struct rpc_auth *auth;
- struct rpc_cred *cred;
- lock_kernel();
- auth = NFS_CLIENT(inode)->cl_auth;
- cred = rpcauth_lookupcred(auth, 0);
- filp->private_data = cred;
- if (filp->f_mode & FMODE_WRITE)
- nfs_set_mmcred(inode, cred);
- unlock_kernel();
- return 0;
- }
- int nfs_release(struct inode *inode, struct file *filp)
- {
- struct rpc_cred *cred;
- lock_kernel();
- cred = nfs_file_cred(filp);
- if (cred)
- put_rpccred(cred);
- unlock_kernel();
- return 0;
- }
- /*
- * This function is called whenever some part of NFS notices that
- * the cached attributes have to be refreshed.
- */
- int
- __nfs_revalidate_inode(struct nfs_server *server, struct inode *inode)
- {
- int status = -ESTALE;
- struct nfs_fattr fattr;
- dfprintk(PAGECACHE, "NFS: revalidating (%x/%Ld)n",
- inode->i_dev, (long long)NFS_FILEID(inode));
- lock_kernel();
- if (!inode || is_bad_inode(inode))
- goto out_nowait;
- if (NFS_STALE(inode) && inode != inode->i_sb->s_root->d_inode)
- goto out_nowait;
- while (NFS_REVALIDATING(inode)) {
- status = nfs_wait_on_inode(inode, NFS_INO_REVALIDATING);
- if (status < 0)
- goto out_nowait;
- if (time_before(jiffies,NFS_READTIME(inode)+NFS_ATTRTIMEO(inode))) {
- status = NFS_STALE(inode) ? -ESTALE : 0;
- goto out_nowait;
- }
- }
- NFS_FLAGS(inode) |= NFS_INO_REVALIDATING;
- status = NFS_PROTO(inode)->getattr(inode, &fattr);
- if (status) {
- dfprintk(PAGECACHE, "nfs_revalidate_inode: (%x/%Ld) getattr failed, error=%dn",
- inode->i_dev, (long long)NFS_FILEID(inode), status);
- if (status == -ESTALE) {
- NFS_FLAGS(inode) |= NFS_INO_STALE;
- if (inode != inode->i_sb->s_root->d_inode)
- remove_inode_hash(inode);
- }
- goto out;
- }
- status = nfs_refresh_inode(inode, &fattr);
- if (status) {
- dfprintk(PAGECACHE, "nfs_revalidate_inode: (%x/%Ld) refresh failed, error=%dn",
- inode->i_dev, (long long)NFS_FILEID(inode), status);
- goto out;
- }
- dfprintk(PAGECACHE, "NFS: (%x/%Ld) revalidation completen",
- inode->i_dev, (long long)NFS_FILEID(inode));
- NFS_FLAGS(inode) &= ~NFS_INO_STALE;
- out:
- NFS_FLAGS(inode) &= ~NFS_INO_REVALIDATING;
- wake_up(&inode->i_wait);
- out_nowait:
- unlock_kernel();
- return status;
- }
- /*
- * nfs_fattr_obsolete - Test if attribute data is newer than cached data
- * @inode: inode
- * @fattr: attributes to test
- *
- * Avoid stuffing the attribute cache with obsolete information.
- * We always accept updates if the attribute cache timed out, or if
- * fattr->ctime is newer than our cached value.
- * If fattr->ctime matches the cached value, we still accept the update
- * if it increases the file size.
- */
- static inline
- int nfs_fattr_obsolete(struct inode *inode, struct nfs_fattr *fattr)
- {
- s64 cdif;
- if (time_after(jiffies, NFS_READTIME(inode)+NFS_ATTRTIMEO(inode)))
- goto out_valid;
- if ((cdif = (s64)fattr->ctime - (s64)NFS_CACHE_CTIME(inode)) > 0)
- goto out_valid;
- /* Ugh... */
- if (cdif == 0 && fattr->size > NFS_CACHE_ISIZE(inode))
- goto out_valid;
- return -1;
- out_valid:
- return 0;
- }
- /*
- * Many nfs protocol calls return the new file attributes after
- * an operation. Here we update the inode to reflect the state
- * of the server's inode.
- *
- * This is a bit tricky because we have to make sure all dirty pages
- * have been sent off to the server before calling invalidate_inode_pages.
- * To make sure no other process adds more write requests while we try
- * our best to flush them, we make them sleep during the attribute refresh.
- *
- * A very similar scenario holds for the dir cache.
- */
- int
- __nfs_refresh_inode(struct inode *inode, struct nfs_fattr *fattr)
- {
- __u64 new_size, new_mtime;
- loff_t new_isize;
- time_t new_atime;
- int invalid = 0;
- dfprintk(VFS, "NFS: refresh_inode(%x/%ld ct=%d info=0x%x)n",
- inode->i_dev, inode->i_ino,
- atomic_read(&inode->i_count), fattr->valid);
- if (NFS_FSID(inode) != fattr->fsid ||
- NFS_FILEID(inode) != fattr->fileid) {
- printk(KERN_ERR "nfs_refresh_inode: inode number mismatchn"
- "expected (0x%Lx/0x%Lx), got (0x%Lx/0x%Lx)n",
- (long long)NFS_FSID(inode), (long long)NFS_FILEID(inode),
- (long long)fattr->fsid, (long long)fattr->fileid);
- goto out_err;
- }
- /*
- * Make sure the inode's type hasn't changed.
- */
- if ((inode->i_mode & S_IFMT) != (fattr->mode & S_IFMT))
- goto out_changed;
- new_mtime = fattr->mtime;
- new_size = fattr->size;
- new_isize = nfs_size_to_loff_t(fattr->size);
- new_atime = nfs_time_to_secs(fattr->atime);
- /* Avoid races */
- if (nfs_fattr_obsolete(inode, fattr))
- goto out_nochange;
- /*
- * Update the read time so we don't revalidate too often.
- */
- NFS_READTIME(inode) = jiffies;
- /*
- * Note: NFS_CACHE_ISIZE(inode) reflects the state of the cache.
- * NOT inode->i_size!!!
- */
- if (NFS_CACHE_ISIZE(inode) != new_size) {
- #ifdef NFS_DEBUG_VERBOSE
- printk(KERN_DEBUG "NFS: isize change on %x/%ldn", inode->i_dev, inode->i_ino);
- #endif
- invalid = 1;
- }
- /*
- * Note: we don't check inode->i_mtime since pipes etc.
- * can change this value in VFS without requiring a
- * cache revalidation.
- */
- if (NFS_CACHE_MTIME(inode) != new_mtime) {
- #ifdef NFS_DEBUG_VERBOSE
- printk(KERN_DEBUG "NFS: mtime change on %x/%ldn", inode->i_dev, inode->i_ino);
- #endif
- invalid = 1;
- }
- /* Check Weak Cache Consistency data.
- * If size and mtime match the pre-operation values, we can
- * assume that any attribute changes were caused by our NFS
- * operation, so there's no need to invalidate the caches.
- */
- if ((fattr->valid & NFS_ATTR_WCC)
- && NFS_CACHE_ISIZE(inode) == fattr->pre_size
- && NFS_CACHE_MTIME(inode) == fattr->pre_mtime) {
- invalid = 0;
- }
- /*
- * If we have pending writebacks, things can get
- * messy.
- */
- if (nfs_have_writebacks(inode) && new_isize < inode->i_size)
- new_isize = inode->i_size;
- NFS_CACHE_CTIME(inode) = fattr->ctime;
- inode->i_ctime = nfs_time_to_secs(fattr->ctime);
- inode->i_atime = new_atime;
- NFS_CACHE_MTIME(inode) = new_mtime;
- inode->i_mtime = nfs_time_to_secs(new_mtime);
- NFS_CACHE_ISIZE(inode) = new_size;
- inode->i_size = new_isize;
- inode->i_mode = fattr->mode;
- inode->i_nlink = fattr->nlink;
- inode->i_uid = fattr->uid;
- inode->i_gid = fattr->gid;
- if (fattr->valid & NFS_ATTR_FATTR_V3) {
- /*
- * report the blocks in 512byte units
- */
- inode->i_blocks = nfs_calc_block_size(fattr->du.nfs3.used);
- inode->i_blksize = inode->i_sb->s_blocksize;
- } else {
- inode->i_blocks = fattr->du.nfs2.blocks;
- inode->i_blksize = fattr->du.nfs2.blocksize;
- }
- inode->i_rdev = 0;
- if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode))
- inode->i_rdev = to_kdev_t(fattr->rdev);
-
- /* Update attrtimeo value */
- if (!invalid && time_after(jiffies, NFS_ATTRTIMEO_UPDATE(inode)+NFS_ATTRTIMEO(inode))) {
- if ((NFS_ATTRTIMEO(inode) <<= 1) > NFS_MAXATTRTIMEO(inode))
- NFS_ATTRTIMEO(inode) = NFS_MAXATTRTIMEO(inode);
- NFS_ATTRTIMEO_UPDATE(inode) = jiffies;
- }
- if (invalid)
- nfs_zap_caches(inode);
- return 0;
- out_nochange:
- if (new_atime - inode->i_atime > 0)
- inode->i_atime = new_atime;
- return 0;
- out_changed:
- /*
- * Big trouble! The inode has become a different object.
- */
- #ifdef NFS_PARANOIA
- printk(KERN_DEBUG "nfs_refresh_inode: inode %ld mode changed, %07o to %07on",
- inode->i_ino, inode->i_mode, fattr->mode);
- #endif
- /*
- * No need to worry about unhashing the dentry, as the
- * lookup validation will know that the inode is bad.
- * (But we fall through to invalidate the caches.)
- */
- nfs_invalidate_inode(inode);
- out_err:
- return -EIO;
- }
- /*
- * File system information
- */
- static DECLARE_FSTYPE(nfs_fs_type, "nfs", nfs_read_super, FS_ODD_RENAME);
- extern int nfs_init_nfspagecache(void);
- extern void nfs_destroy_nfspagecache(void);
- extern int nfs_init_readpagecache(void);
- extern int nfs_destroy_readpagecache(void);
- extern int nfs_init_writepagecache(void);
- extern int nfs_destroy_writepagecache(void);
- /*
- * Initialize NFS
- */
- static int __init init_nfs_fs(void)
- {
- int err;
- err = nfs_init_nfspagecache();
- if (err)
- return err;
- err = nfs_init_readpagecache();
- if (err)
- return err;
- err = nfs_init_writepagecache();
- if (err)
- return err;
- #ifdef CONFIG_PROC_FS
- rpc_proc_register(&nfs_rpcstat);
- #endif
- return register_filesystem(&nfs_fs_type);
- }
- static void __exit exit_nfs_fs(void)
- {
- nfs_destroy_writepagecache();
- nfs_destroy_readpagecache();
- nfs_destroy_nfspagecache();
- #ifdef CONFIG_PROC_FS
- rpc_proc_unregister("nfs");
- #endif
- unregister_filesystem(&nfs_fs_type);
- }
- EXPORT_NO_SYMBOLS;
- /* Not quite true; I just maintain it */
- MODULE_AUTHOR("Olaf Kirch <okir@monad.swb.de>");
- MODULE_LICENSE("GPL");
- module_init(init_nfs_fs)
- module_exit(exit_nfs_fs)