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inode.c
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/*
* linux/fs/nfs/inode.c
*
* Copyright (C) 1992 Rick Sladkey
*
* nfs inode and superblock handling functions
*
* Modularised by Alan Cox <[email protected]>, 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.
*
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/sched.h>
#include <linux/time.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/string.h>
#include <linux/stat.h>
#include <linux/errno.h>
#include <linux/unistd.h>
#include <linux/sunrpc/clnt.h>
#include <linux/sunrpc/stats.h>
#include <linux/sunrpc/metrics.h>
#include <linux/nfs_fs.h>
#include <linux/nfs_mount.h>
#include <linux/nfs4_mount.h>
#include <linux/lockd/bind.h>
#include <linux/seq_file.h>
#include <linux/mount.h>
#include <linux/nfs_idmap.h>
#include <linux/vfs.h>
#include <linux/inet.h>
#include <linux/nfs_xdr.h>
#include <asm/system.h>
#include <asm/uaccess.h>
#include "nfs4_fs.h"
#include "callback.h"
#include "delegation.h"
#include "iostat.h"
#include "internal.h"
#include "fscache.h"
#include "dns_resolve.h"
#define NFSDBG_FACILITY NFSDBG_VFS
#define NFS_64_BIT_INODE_NUMBERS_ENABLED 1
/* Default is to see 64-bit inode numbers */
static int enable_ino64 = NFS_64_BIT_INODE_NUMBERS_ENABLED;
static void nfs_invalidate_inode(struct inode *);
static int nfs_update_inode(struct inode *, struct nfs_fattr *);
static struct kmem_cache * nfs_inode_cachep;
static inline unsigned long
nfs_fattr_to_ino_t(struct nfs_fattr *fattr)
{
return nfs_fileid_to_ino_t(fattr->fileid);
}
/**
* nfs_wait_bit_killable - helper for functions that are sleeping on bit locks
* @word: long word containing the bit lock
*/
int nfs_wait_bit_killable(void *word)
{
if (fatal_signal_pending(current))
return -ERESTARTSYS;
schedule();
return 0;
}
/**
* nfs_compat_user_ino64 - returns the user-visible inode number
* @fileid: 64-bit fileid
*
* This function returns a 32-bit inode number if the boot parameter
* nfs.enable_ino64 is zero.
*/
u64 nfs_compat_user_ino64(u64 fileid)
{
int ino;
if (enable_ino64)
return fileid;
ino = fileid;
if (sizeof(ino) < sizeof(fileid))
ino ^= fileid >> (sizeof(fileid)-sizeof(ino)) * 8;
return ino;
}
void nfs_clear_inode(struct inode *inode)
{
/*
* The following should never happen...
*/
BUG_ON(nfs_have_writebacks(inode));
BUG_ON(!list_empty(&NFS_I(inode)->open_files));
nfs_zap_acl_cache(inode);
nfs_access_zap_cache(inode);
nfs_fscache_release_inode_cookie(inode);
}
/**
* nfs_sync_mapping - helper to flush all mmapped dirty data to disk
*/
int nfs_sync_mapping(struct address_space *mapping)
{
int ret = 0;
if (mapping->nrpages != 0) {
unmap_mapping_range(mapping, 0, 0, 0);
ret = nfs_wb_all(mapping->host);
}
return ret;
}
/*
* Invalidate the local caches
*/
static void nfs_zap_caches_locked(struct inode *inode)
{
struct nfs_inode *nfsi = NFS_I(inode);
int mode = inode->i_mode;
nfs_inc_stats(inode, NFSIOS_ATTRINVALIDATE);
nfsi->attrtimeo = NFS_MINATTRTIMEO(inode);
nfsi->attrtimeo_timestamp = jiffies;
memset(NFS_COOKIEVERF(inode), 0, sizeof(NFS_COOKIEVERF(inode)));
if (S_ISREG(mode) || S_ISDIR(mode) || S_ISLNK(mode))
nfsi->cache_validity |= NFS_INO_INVALID_ATTR|NFS_INO_INVALID_DATA|NFS_INO_INVALID_ACCESS|NFS_INO_INVALID_ACL|NFS_INO_REVAL_PAGECACHE;
else
nfsi->cache_validity |= NFS_INO_INVALID_ATTR|NFS_INO_INVALID_ACCESS|NFS_INO_INVALID_ACL|NFS_INO_REVAL_PAGECACHE;
}
void nfs_zap_caches(struct inode *inode)
{
spin_lock(&inode->i_lock);
nfs_zap_caches_locked(inode);
spin_unlock(&inode->i_lock);
}
void nfs_zap_mapping(struct inode *inode, struct address_space *mapping)
{
if (mapping->nrpages != 0) {
spin_lock(&inode->i_lock);
NFS_I(inode)->cache_validity |= NFS_INO_INVALID_DATA;
spin_unlock(&inode->i_lock);
}
}
void nfs_zap_acl_cache(struct inode *inode)
{
void (*clear_acl_cache)(struct inode *);
clear_acl_cache = NFS_PROTO(inode)->clear_acl_cache;
if (clear_acl_cache != NULL)
clear_acl_cache(inode);
spin_lock(&inode->i_lock);
NFS_I(inode)->cache_validity &= ~NFS_INO_INVALID_ACL;
spin_unlock(&inode->i_lock);
}
void nfs_invalidate_atime(struct inode *inode)
{
spin_lock(&inode->i_lock);
NFS_I(inode)->cache_validity |= NFS_INO_INVALID_ATIME;
spin_unlock(&inode->i_lock);
}
/*
* Invalidate, but do not unhash, the inode.
* NB: must be called with inode->i_lock held!
*/
static void nfs_invalidate_inode(struct inode *inode)
{
set_bit(NFS_INO_STALE, &NFS_I(inode)->flags);
nfs_zap_caches_locked(inode);
}
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, 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_FILEID(inode) != fattr->fileid)
return 0;
if (nfs_compare_fh(NFS_FH(inode), fh))
return 0;
if (is_bad_inode(inode) || NFS_STALE(inode))
return 0;
return 1;
}
static int
nfs_init_locked(struct inode *inode, void *opaque)
{
struct nfs_find_desc *desc = (struct nfs_find_desc *)opaque;
struct nfs_fattr *fattr = desc->fattr;
set_nfs_fileid(inode, fattr->fileid);
nfs_copy_fh(NFS_FH(inode), desc->fh);
return 0;
}
/* Don't use READDIRPLUS on directories that we believe are too large */
#define NFS_LIMIT_READDIRPLUS (8*PAGE_SIZE)
/*
* This is our front-end to iget that looks up inodes by file handle
* instead of inode number.
*/
struct inode *
nfs_fhget(struct super_block *sb, struct nfs_fh *fh, struct nfs_fattr *fattr)
{
struct nfs_find_desc desc = {
.fh = fh,
.fattr = fattr
};
struct inode *inode = ERR_PTR(-ENOENT);
unsigned long hash;
if ((fattr->valid & NFS_ATTR_FATTR_FILEID) == 0)
goto out_no_inode;
if ((fattr->valid & NFS_ATTR_FATTR_TYPE) == 0)
goto out_no_inode;
hash = nfs_fattr_to_ino_t(fattr);
inode = iget5_locked(sb, hash, nfs_find_actor, nfs_init_locked, &desc);
if (inode == NULL) {
inode = ERR_PTR(-ENOMEM);
goto out_no_inode;
}
if (inode->i_state & I_NEW) {
struct nfs_inode *nfsi = NFS_I(inode);
unsigned long now = jiffies;
/* We set i_ino for the few things that still rely on it,
* such as stat(2) */
inode->i_ino = hash;
/* We can't support update_atime(), since the server will reset it */
inode->i_flags |= S_NOATIME|S_NOCMTIME;
inode->i_mode = fattr->mode;
if ((fattr->valid & NFS_ATTR_FATTR_MODE) == 0
&& nfs_server_capable(inode, NFS_CAP_MODE))
nfsi->cache_validity |= NFS_INO_INVALID_ATTR
| NFS_INO_INVALID_ACCESS
| NFS_INO_INVALID_ACL;
/* 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_SB(sb)->nfs_client->rpc_ops->file_inode_ops;
if (S_ISREG(inode->i_mode)) {
inode->i_fop = &nfs_file_operations;
inode->i_data.a_ops = &nfs_file_aops;
inode->i_data.backing_dev_info = &NFS_SB(sb)->backing_dev_info;
} else if (S_ISDIR(inode->i_mode)) {
inode->i_op = NFS_SB(sb)->nfs_client->rpc_ops->dir_inode_ops;
inode->i_fop = &nfs_dir_operations;
if (nfs_server_capable(inode, NFS_CAP_READDIRPLUS)
&& fattr->size <= NFS_LIMIT_READDIRPLUS)
set_bit(NFS_INO_ADVISE_RDPLUS, &NFS_I(inode)->flags);
/* Deal with crossing mountpoints */
if ((fattr->valid & NFS_ATTR_FATTR_FSID)
&& !nfs_fsid_equal(&NFS_SB(sb)->fsid, &fattr->fsid)) {
if (fattr->valid & NFS_ATTR_FATTR_V4_REFERRAL)
inode->i_op = &nfs_referral_inode_operations;
else
inode->i_op = &nfs_mountpoint_inode_operations;
inode->i_fop = NULL;
set_bit(NFS_INO_MOUNTPOINT, &nfsi->flags);
}
} else if (S_ISLNK(inode->i_mode))
inode->i_op = &nfs_symlink_inode_operations;
else
init_special_inode(inode, inode->i_mode, fattr->rdev);
memset(&inode->i_atime, 0, sizeof(inode->i_atime));
memset(&inode->i_mtime, 0, sizeof(inode->i_mtime));
memset(&inode->i_ctime, 0, sizeof(inode->i_ctime));
nfsi->change_attr = 0;
inode->i_size = 0;
inode->i_nlink = 0;
inode->i_uid = -2;
inode->i_gid = -2;
inode->i_blocks = 0;
memset(nfsi->cookieverf, 0, sizeof(nfsi->cookieverf));
nfsi->read_cache_jiffies = fattr->time_start;
nfsi->attr_gencount = fattr->gencount;
if (fattr->valid & NFS_ATTR_FATTR_ATIME)
inode->i_atime = fattr->atime;
else if (nfs_server_capable(inode, NFS_CAP_ATIME))
nfsi->cache_validity |= NFS_INO_INVALID_ATTR;
if (fattr->valid & NFS_ATTR_FATTR_MTIME)
inode->i_mtime = fattr->mtime;
else if (nfs_server_capable(inode, NFS_CAP_MTIME))
nfsi->cache_validity |= NFS_INO_INVALID_ATTR
| NFS_INO_INVALID_DATA;
if (fattr->valid & NFS_ATTR_FATTR_CTIME)
inode->i_ctime = fattr->ctime;
else if (nfs_server_capable(inode, NFS_CAP_CTIME))
nfsi->cache_validity |= NFS_INO_INVALID_ATTR
| NFS_INO_INVALID_ACCESS
| NFS_INO_INVALID_ACL;
if (fattr->valid & NFS_ATTR_FATTR_CHANGE)
nfsi->change_attr = fattr->change_attr;
else if (nfs_server_capable(inode, NFS_CAP_CHANGE_ATTR))
nfsi->cache_validity |= NFS_INO_INVALID_ATTR
| NFS_INO_INVALID_DATA;
if (fattr->valid & NFS_ATTR_FATTR_SIZE)
inode->i_size = nfs_size_to_loff_t(fattr->size);
else
nfsi->cache_validity |= NFS_INO_INVALID_ATTR
| NFS_INO_INVALID_DATA
| NFS_INO_REVAL_PAGECACHE;
if (fattr->valid & NFS_ATTR_FATTR_NLINK)
inode->i_nlink = fattr->nlink;
else if (nfs_server_capable(inode, NFS_CAP_NLINK))
nfsi->cache_validity |= NFS_INO_INVALID_ATTR;
if (fattr->valid & NFS_ATTR_FATTR_OWNER)
inode->i_uid = fattr->uid;
else if (nfs_server_capable(inode, NFS_CAP_OWNER))
nfsi->cache_validity |= NFS_INO_INVALID_ATTR
| NFS_INO_INVALID_ACCESS
| NFS_INO_INVALID_ACL;
if (fattr->valid & NFS_ATTR_FATTR_GROUP)
inode->i_gid = fattr->gid;
else if (nfs_server_capable(inode, NFS_CAP_OWNER_GROUP))
nfsi->cache_validity |= NFS_INO_INVALID_ATTR
| NFS_INO_INVALID_ACCESS
| NFS_INO_INVALID_ACL;
if (fattr->valid & NFS_ATTR_FATTR_BLOCKS_USED)
inode->i_blocks = fattr->du.nfs2.blocks;
if (fattr->valid & NFS_ATTR_FATTR_SPACE_USED) {
/*
* report the blocks in 512byte units
*/
inode->i_blocks = nfs_calc_block_size(fattr->du.nfs3.used);
}
nfsi->attrtimeo = NFS_MINATTRTIMEO(inode);
nfsi->attrtimeo_timestamp = now;
nfsi->access_cache = RB_ROOT;
nfs_fscache_init_inode_cookie(inode);
unlock_new_inode(inode);
} else
nfs_refresh_inode(inode, fattr);
dprintk("NFS: nfs_fhget(%s/%Ld ct=%d)\n",
inode->i_sb->s_id,
(long long)NFS_FILEID(inode),
atomic_read(&inode->i_count));
out:
return inode;
out_no_inode:
dprintk("nfs_fhget: iget failed with error %ld\n", PTR_ERR(inode));
goto out;
}
#define NFS_VALID_ATTRS (ATTR_MODE|ATTR_UID|ATTR_GID|ATTR_SIZE|ATTR_ATIME|ATTR_ATIME_SET|ATTR_MTIME|ATTR_MTIME_SET|ATTR_FILE)
int
nfs_setattr(struct dentry *dentry, struct iattr *attr)
{
struct inode *inode = dentry->d_inode;
struct nfs_fattr fattr;
int error;
nfs_inc_stats(inode, NFSIOS_VFSSETATTR);
/* skip mode change if it's just for clearing setuid/setgid */
if (attr->ia_valid & (ATTR_KILL_SUID | ATTR_KILL_SGID))
attr->ia_valid &= ~ATTR_MODE;
if (attr->ia_valid & ATTR_SIZE) {
if (!S_ISREG(inode->i_mode) || attr->ia_size == i_size_read(inode))
attr->ia_valid &= ~ATTR_SIZE;
}
/* Optimization: if the end result is no change, don't RPC */
attr->ia_valid &= NFS_VALID_ATTRS;
if ((attr->ia_valid & ~ATTR_FILE) == 0)
return 0;
/* Write all dirty data */
if (S_ISREG(inode->i_mode)) {
filemap_write_and_wait(inode->i_mapping);
nfs_wb_all(inode);
}
/*
* Return any delegations if we're going to change ACLs
*/
if ((attr->ia_valid & (ATTR_MODE|ATTR_UID|ATTR_GID)) != 0)
nfs_inode_return_delegation(inode);
error = NFS_PROTO(inode)->setattr(dentry, &fattr, attr);
if (error == 0)
nfs_refresh_inode(inode, &fattr);
return error;
}
/**
* nfs_vmtruncate - unmap mappings "freed" by truncate() syscall
* @inode: inode of the file used
* @offset: file offset to start truncating
*
* This is a copy of the common vmtruncate, but with the locking
* corrected to take into account the fact that NFS requires
* inode->i_size to be updated under the inode->i_lock.
*/
static int nfs_vmtruncate(struct inode * inode, loff_t offset)
{
loff_t oldsize;
int err;
err = inode_newsize_ok(inode, offset);
if (err)
goto out;
spin_lock(&inode->i_lock);
oldsize = inode->i_size;
i_size_write(inode, offset);
spin_unlock(&inode->i_lock);
truncate_pagecache(inode, oldsize, offset);
out:
return err;
}
/**
* nfs_setattr_update_inode - Update inode metadata after a setattr call.
* @inode: pointer to struct inode
* @attr: pointer to struct iattr
*
* Note: we do this in the *proc.c in order to ensure that
* it works for things like exclusive creates too.
*/
void nfs_setattr_update_inode(struct inode *inode, struct iattr *attr)
{
if ((attr->ia_valid & (ATTR_MODE|ATTR_UID|ATTR_GID)) != 0) {
spin_lock(&inode->i_lock);
if ((attr->ia_valid & ATTR_MODE) != 0) {
int mode = attr->ia_mode & S_IALLUGO;
mode |= inode->i_mode & ~S_IALLUGO;
inode->i_mode = mode;
}
if ((attr->ia_valid & ATTR_UID) != 0)
inode->i_uid = attr->ia_uid;
if ((attr->ia_valid & ATTR_GID) != 0)
inode->i_gid = attr->ia_gid;
NFS_I(inode)->cache_validity |= NFS_INO_INVALID_ACCESS|NFS_INO_INVALID_ACL;
spin_unlock(&inode->i_lock);
}
if ((attr->ia_valid & ATTR_SIZE) != 0) {
nfs_inc_stats(inode, NFSIOS_SETATTRTRUNC);
nfs_vmtruncate(inode, attr->ia_size);
}
}
int nfs_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
{
struct inode *inode = dentry->d_inode;
int need_atime = NFS_I(inode)->cache_validity & NFS_INO_INVALID_ATIME;
int err;
/* Flush out writes to the server in order to update c/mtime. */
if (S_ISREG(inode->i_mode)) {
err = filemap_write_and_wait(inode->i_mapping);
if (err)
goto out;
}
/*
* We may force a getattr if the user cares about atime.
*
* Note that we only have to check the vfsmount flags here:
* - NFS always sets S_NOATIME by so checking it would give a
* bogus result
* - NFS never sets MS_NOATIME or MS_NODIRATIME so there is
* no point in checking those.
*/
if ((mnt->mnt_flags & MNT_NOATIME) ||
((mnt->mnt_flags & MNT_NODIRATIME) && S_ISDIR(inode->i_mode)))
need_atime = 0;
if (need_atime)
err = __nfs_revalidate_inode(NFS_SERVER(inode), inode);
else
err = nfs_revalidate_inode(NFS_SERVER(inode), inode);
if (!err) {
generic_fillattr(inode, stat);
stat->ino = nfs_compat_user_ino64(NFS_FILEID(inode));
}
out:
return err;
}
/**
* nfs_close_context - Common close_context() routine NFSv2/v3
* @ctx: pointer to context
* @is_sync: is this a synchronous close
*
* always ensure that the attributes are up to date if we're mounted
* with close-to-open semantics
*/
void nfs_close_context(struct nfs_open_context *ctx, int is_sync)
{
struct inode *inode;
struct nfs_server *server;
if (!(ctx->mode & FMODE_WRITE))
return;
if (!is_sync)
return;
inode = ctx->path.dentry->d_inode;
if (!list_empty(&NFS_I(inode)->open_files))
return;
server = NFS_SERVER(inode);
if (server->flags & NFS_MOUNT_NOCTO)
return;
nfs_revalidate_inode(server, inode);
}
static struct nfs_open_context *alloc_nfs_open_context(struct path *path, struct rpc_cred *cred)
{
struct nfs_open_context *ctx;
ctx = kmalloc(sizeof(*ctx), GFP_KERNEL);
if (ctx != NULL) {
ctx->path = *path;
path_get(&ctx->path);
ctx->cred = get_rpccred(cred);
ctx->state = NULL;
ctx->lockowner = current->files;
ctx->flags = 0;
ctx->error = 0;
ctx->dir_cookie = 0;
atomic_set(&ctx->count, 1);
}
return ctx;
}
struct nfs_open_context *get_nfs_open_context(struct nfs_open_context *ctx)
{
if (ctx != NULL)
atomic_inc(&ctx->count);
return ctx;
}
static void __put_nfs_open_context(struct nfs_open_context *ctx, int is_sync)
{
struct inode *inode = ctx->path.dentry->d_inode;
if (!atomic_dec_and_lock(&ctx->count, &inode->i_lock))
return;
list_del(&ctx->list);
spin_unlock(&inode->i_lock);
NFS_PROTO(inode)->close_context(ctx, is_sync);
if (ctx->cred != NULL)
put_rpccred(ctx->cred);
path_put(&ctx->path);
kfree(ctx);
}
void put_nfs_open_context(struct nfs_open_context *ctx)
{
__put_nfs_open_context(ctx, 0);
}
/*
* Ensure that mmap has a recent RPC credential for use when writing out
* shared pages
*/
static void nfs_file_set_open_context(struct file *filp, struct nfs_open_context *ctx)
{
struct inode *inode = filp->f_path.dentry->d_inode;
struct nfs_inode *nfsi = NFS_I(inode);
filp->private_data = get_nfs_open_context(ctx);
spin_lock(&inode->i_lock);
list_add(&ctx->list, &nfsi->open_files);
spin_unlock(&inode->i_lock);
}
/*
* Given an inode, search for an open context with the desired characteristics
*/
struct nfs_open_context *nfs_find_open_context(struct inode *inode, struct rpc_cred *cred, fmode_t mode)
{
struct nfs_inode *nfsi = NFS_I(inode);
struct nfs_open_context *pos, *ctx = NULL;
spin_lock(&inode->i_lock);
list_for_each_entry(pos, &nfsi->open_files, list) {
if (cred != NULL && pos->cred != cred)
continue;
if ((pos->mode & mode) == mode) {
ctx = get_nfs_open_context(pos);
break;
}
}
spin_unlock(&inode->i_lock);
return ctx;
}
static void nfs_file_clear_open_context(struct file *filp)
{
struct inode *inode = filp->f_path.dentry->d_inode;
struct nfs_open_context *ctx = nfs_file_open_context(filp);
if (ctx) {
filp->private_data = NULL;
spin_lock(&inode->i_lock);
list_move_tail(&ctx->list, &NFS_I(inode)->open_files);
spin_unlock(&inode->i_lock);
__put_nfs_open_context(ctx, filp->f_flags & O_DIRECT ? 0 : 1);
}
}
/*
* These allocate and release file read/write context information.
*/
int nfs_open(struct inode *inode, struct file *filp)
{
struct nfs_open_context *ctx;
struct rpc_cred *cred;
cred = rpc_lookup_cred();
if (IS_ERR(cred))
return PTR_ERR(cred);
ctx = alloc_nfs_open_context(&filp->f_path, cred);
put_rpccred(cred);
if (ctx == NULL)
return -ENOMEM;
ctx->mode = filp->f_mode;
nfs_file_set_open_context(filp, ctx);
put_nfs_open_context(ctx);
nfs_fscache_set_inode_cookie(inode, filp);
return 0;
}
int nfs_release(struct inode *inode, struct file *filp)
{
nfs_file_clear_open_context(filp);
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;
struct nfs_inode *nfsi = NFS_I(inode);
dfprintk(PAGECACHE, "NFS: revalidating (%s/%Ld)\n",
inode->i_sb->s_id, (long long)NFS_FILEID(inode));
if (is_bad_inode(inode))
goto out;
if (NFS_STALE(inode))
goto out;
nfs_inc_stats(inode, NFSIOS_INODEREVALIDATE);
status = NFS_PROTO(inode)->getattr(server, NFS_FH(inode), &fattr);
if (status != 0) {
dfprintk(PAGECACHE, "nfs_revalidate_inode: (%s/%Ld) getattr failed, error=%d\n",
inode->i_sb->s_id,
(long long)NFS_FILEID(inode), status);
if (status == -ESTALE) {
nfs_zap_caches(inode);
if (!S_ISDIR(inode->i_mode))
set_bit(NFS_INO_STALE, &NFS_I(inode)->flags);
}
goto out;
}
status = nfs_refresh_inode(inode, &fattr);
if (status) {
dfprintk(PAGECACHE, "nfs_revalidate_inode: (%s/%Ld) refresh failed, error=%d\n",
inode->i_sb->s_id,
(long long)NFS_FILEID(inode), status);
goto out;
}
if (nfsi->cache_validity & NFS_INO_INVALID_ACL)
nfs_zap_acl_cache(inode);
dfprintk(PAGECACHE, "NFS: (%s/%Ld) revalidation complete\n",
inode->i_sb->s_id,
(long long)NFS_FILEID(inode));
out:
return status;
}
int nfs_attribute_timeout(struct inode *inode)
{
struct nfs_inode *nfsi = NFS_I(inode);
if (nfs_have_delegation(inode, FMODE_READ))
return 0;
return !time_in_range_open(jiffies, nfsi->read_cache_jiffies, nfsi->read_cache_jiffies + nfsi->attrtimeo);
}
/**
* nfs_revalidate_inode - Revalidate the inode attributes
* @server - pointer to nfs_server struct
* @inode - pointer to inode struct
*
* Updates inode attribute information by retrieving the data from the server.
*/
int nfs_revalidate_inode(struct nfs_server *server, struct inode *inode)
{
if (!(NFS_I(inode)->cache_validity & NFS_INO_INVALID_ATTR)
&& !nfs_attribute_timeout(inode))
return NFS_STALE(inode) ? -ESTALE : 0;
return __nfs_revalidate_inode(server, inode);
}
static int nfs_invalidate_mapping(struct inode *inode, struct address_space *mapping)
{
struct nfs_inode *nfsi = NFS_I(inode);
if (mapping->nrpages != 0) {
int ret = invalidate_inode_pages2(mapping);
if (ret < 0)
return ret;
}
spin_lock(&inode->i_lock);
nfsi->cache_validity &= ~NFS_INO_INVALID_DATA;
if (S_ISDIR(inode->i_mode))
memset(nfsi->cookieverf, 0, sizeof(nfsi->cookieverf));
spin_unlock(&inode->i_lock);
nfs_inc_stats(inode, NFSIOS_DATAINVALIDATE);
nfs_fscache_reset_inode_cookie(inode);
dfprintk(PAGECACHE, "NFS: (%s/%Ld) data cache invalidated\n",
inode->i_sb->s_id, (long long)NFS_FILEID(inode));
return 0;
}
/**
* nfs_revalidate_mapping - Revalidate the pagecache
* @inode - pointer to host inode
* @mapping - pointer to mapping
*/
int nfs_revalidate_mapping(struct inode *inode, struct address_space *mapping)
{
struct nfs_inode *nfsi = NFS_I(inode);
int ret = 0;
if ((nfsi->cache_validity & NFS_INO_REVAL_PAGECACHE)
|| nfs_attribute_timeout(inode) || NFS_STALE(inode)) {
ret = __nfs_revalidate_inode(NFS_SERVER(inode), inode);
if (ret < 0)
goto out;
}
if (nfsi->cache_validity & NFS_INO_INVALID_DATA)
ret = nfs_invalidate_mapping(inode, mapping);
out:
return ret;
}
static void nfs_wcc_update_inode(struct inode *inode, struct nfs_fattr *fattr)
{
struct nfs_inode *nfsi = NFS_I(inode);
if ((fattr->valid & NFS_ATTR_FATTR_PRECHANGE)
&& (fattr->valid & NFS_ATTR_FATTR_CHANGE)
&& nfsi->change_attr == fattr->pre_change_attr) {
nfsi->change_attr = fattr->change_attr;
if (S_ISDIR(inode->i_mode))
nfsi->cache_validity |= NFS_INO_INVALID_DATA;
}
/* If we have atomic WCC data, we may update some attributes */
if ((fattr->valid & NFS_ATTR_FATTR_PRECTIME)
&& (fattr->valid & NFS_ATTR_FATTR_CTIME)
&& timespec_equal(&inode->i_ctime, &fattr->pre_ctime))
memcpy(&inode->i_ctime, &fattr->ctime, sizeof(inode->i_ctime));
if ((fattr->valid & NFS_ATTR_FATTR_PREMTIME)
&& (fattr->valid & NFS_ATTR_FATTR_MTIME)
&& timespec_equal(&inode->i_mtime, &fattr->pre_mtime)) {
memcpy(&inode->i_mtime, &fattr->mtime, sizeof(inode->i_mtime));
if (S_ISDIR(inode->i_mode))
nfsi->cache_validity |= NFS_INO_INVALID_DATA;
}
if ((fattr->valid & NFS_ATTR_FATTR_PRESIZE)
&& (fattr->valid & NFS_ATTR_FATTR_SIZE)
&& i_size_read(inode) == nfs_size_to_loff_t(fattr->pre_size)
&& nfsi->npages == 0)
i_size_write(inode, nfs_size_to_loff_t(fattr->size));
}
/**
* nfs_check_inode_attributes - verify consistency of the inode attribute cache
* @inode - pointer to inode
* @fattr - updated attributes
*
* Verifies the attribute cache. If we have just changed the attributes,
* so that fattr carries weak cache consistency data, then it may
* also update the ctime/mtime/change_attribute.
*/
static int nfs_check_inode_attributes(struct inode *inode, struct nfs_fattr *fattr)
{
struct nfs_inode *nfsi = NFS_I(inode);
loff_t cur_size, new_isize;
unsigned long invalid = 0;
/* Has the inode gone and changed behind our back? */
if ((fattr->valid & NFS_ATTR_FATTR_FILEID) && nfsi->fileid != fattr->fileid)
return -EIO;
if ((fattr->valid & NFS_ATTR_FATTR_TYPE) && (inode->i_mode & S_IFMT) != (fattr->mode & S_IFMT))
return -EIO;
if ((fattr->valid & NFS_ATTR_FATTR_CHANGE) != 0 &&
nfsi->change_attr != fattr->change_attr)
invalid |= NFS_INO_INVALID_ATTR|NFS_INO_REVAL_PAGECACHE;
/* Verify a few of the more important attributes */
if ((fattr->valid & NFS_ATTR_FATTR_MTIME) && !timespec_equal(&inode->i_mtime, &fattr->mtime))
invalid |= NFS_INO_INVALID_ATTR|NFS_INO_REVAL_PAGECACHE;
if (fattr->valid & NFS_ATTR_FATTR_SIZE) {
cur_size = i_size_read(inode);
new_isize = nfs_size_to_loff_t(fattr->size);
if (cur_size != new_isize && nfsi->npages == 0)
invalid |= NFS_INO_INVALID_ATTR|NFS_INO_REVAL_PAGECACHE;
}
/* Have any file permissions changed? */
if ((fattr->valid & NFS_ATTR_FATTR_MODE) && (inode->i_mode & S_IALLUGO) != (fattr->mode & S_IALLUGO))
invalid |= NFS_INO_INVALID_ATTR | NFS_INO_INVALID_ACCESS | NFS_INO_INVALID_ACL;
if ((fattr->valid & NFS_ATTR_FATTR_OWNER) && inode->i_uid != fattr->uid)
invalid |= NFS_INO_INVALID_ATTR | NFS_INO_INVALID_ACCESS | NFS_INO_INVALID_ACL;
if ((fattr->valid & NFS_ATTR_FATTR_GROUP) && inode->i_gid != fattr->gid)
invalid |= NFS_INO_INVALID_ATTR | NFS_INO_INVALID_ACCESS | NFS_INO_INVALID_ACL;
/* Has the link count changed? */
if ((fattr->valid & NFS_ATTR_FATTR_NLINK) && inode->i_nlink != fattr->nlink)
invalid |= NFS_INO_INVALID_ATTR;
if ((fattr->valid & NFS_ATTR_FATTR_ATIME) && !timespec_equal(&inode->i_atime, &fattr->atime))
invalid |= NFS_INO_INVALID_ATIME;
if (invalid != 0)
nfsi->cache_validity |= invalid;
nfsi->read_cache_jiffies = fattr->time_start;
return 0;
}
static int nfs_ctime_need_update(const struct inode *inode, const struct nfs_fattr *fattr)
{
if (!(fattr->valid & NFS_ATTR_FATTR_CTIME))
return 0;
return timespec_compare(&fattr->ctime, &inode->i_ctime) > 0;
}
static int nfs_size_need_update(const struct inode *inode, const struct nfs_fattr *fattr)
{
if (!(fattr->valid & NFS_ATTR_FATTR_SIZE))
return 0;
return nfs_size_to_loff_t(fattr->size) > i_size_read(inode);
}
static atomic_long_t nfs_attr_generation_counter;
static unsigned long nfs_read_attr_generation_counter(void)
{
return atomic_long_read(&nfs_attr_generation_counter);
}
unsigned long nfs_inc_attr_generation_counter(void)
{
return atomic_long_inc_return(&nfs_attr_generation_counter);
}
void nfs_fattr_init(struct nfs_fattr *fattr)
{
fattr->valid = 0;
fattr->time_start = jiffies;
fattr->gencount = nfs_inc_attr_generation_counter();
}
/**
* nfs_inode_attrs_need_update - check if the inode attributes need updating
* @inode - pointer to inode
* @fattr - attributes
*
* Attempt to divine whether or not an RPC call reply carrying stale
* attributes got scheduled after another call carrying updated ones.
*
* To do so, the function first assumes that a more recent ctime means
* that the attributes in fattr are newer, however it also attempt to
* catch the case where ctime either didn't change, or went backwards
* (if someone reset the clock on the server) by looking at whether
* or not this RPC call was started after the inode was last updated.
* Note also the check for wraparound of 'attr_gencount'
*
* The function returns 'true' if it thinks the attributes in 'fattr' are
* more recent than the ones cached in the inode.
*
*/
static int nfs_inode_attrs_need_update(const struct inode *inode, const struct nfs_fattr *fattr)
{
const struct nfs_inode *nfsi = NFS_I(inode);
return ((long)fattr->gencount - (long)nfsi->attr_gencount) > 0 ||
nfs_ctime_need_update(inode, fattr) ||
nfs_size_need_update(inode, fattr) ||
((long)nfsi->attr_gencount - (long)nfs_read_attr_generation_counter() > 0);
}
static int nfs_refresh_inode_locked(struct inode *inode, struct nfs_fattr *fattr)
{
if (nfs_inode_attrs_need_update(inode, fattr))
return nfs_update_inode(inode, fattr);
return nfs_check_inode_attributes(inode, fattr);
}
/**
* nfs_refresh_inode - try to update the inode attribute cache
* @inode - pointer to inode
* @fattr - updated attributes
*
* Check that an RPC call that returned attributes has not overlapped with
* other recent updates of the inode metadata, then decide whether it is
* safe to do a full update of the inode attributes, or whether just to
* call nfs_check_inode_attributes.
*/
int nfs_refresh_inode(struct inode *inode, struct nfs_fattr *fattr)
{
int status;
if ((fattr->valid & NFS_ATTR_FATTR) == 0)
return 0;
spin_lock(&inode->i_lock);
status = nfs_refresh_inode_locked(inode, fattr);
spin_unlock(&inode->i_lock);
return status;
}
static int nfs_post_op_update_inode_locked(struct inode *inode, struct nfs_fattr *fattr)
{
struct nfs_inode *nfsi = NFS_I(inode);
nfsi->cache_validity |= NFS_INO_INVALID_ATTR|NFS_INO_REVAL_PAGECACHE;
if (S_ISDIR(inode->i_mode))
nfsi->cache_validity |= NFS_INO_INVALID_DATA;
if ((fattr->valid & NFS_ATTR_FATTR) == 0)
return 0;
return nfs_refresh_inode_locked(inode, fattr);
}
/**
* nfs_post_op_update_inode - try to update the inode attribute cache
* @inode - pointer to inode
* @fattr - updated attributes
*
* After an operation that has changed the inode metadata, mark the
* attribute cache as being invalid, then try to update it.
*
* NB: if the server didn't return any post op attributes, this
* function will force the retrieval of attributes before the next
* NFS request. Thus it should be used only for operations that
* are expected to change one or more attributes, to avoid