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/*
* 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 requests\n", 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 = %d\n", -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 kernel\n",
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 failed\n");
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 argument\n");
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 = %d\n", -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, " \t\n\\");
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 failed\n");
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=%d\n", 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=%d\n",
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=%d\n",
inode->i_dev, (long long)NFS_FILEID(inode), status);
goto out;
}
dfprintk(PAGECACHE, "NFS: (%x/%Ld) revalidation complete\n",
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 mismatch\n"
"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/%ld\n", 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/%ld\n", 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 %07o\n",
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)
|