- 根目录:
- fs
- nfs
- inode.c
/*
* linux/fs/nfs/inode.c
*
* Copyright (C) 1992 Rick Sladkey
*
* nfs inode and superblock handling functions
*
* Modularised by Alan Cox <alan@lxorguk.ukuu.org.uk>, 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/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/vfs.h>
#include <linux/inet.h>
#include <linux/nfs_xdr.h>
#include <linux/slab.h>
#include <linux/compat.h>
#include <linux/freezer.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 "pnfs.h"
#include "nfs.h"
#include "netns.h"
#include "nfstrace.h"
#define NFSDBG_FACILITY NFSDBG_VFS
#define NFS_64_BIT_INODE_NUMBERS_ENABLED 1
/* Default is to see 64-bit inode numbers */
static bool 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(struct wait_bit_key *key, int mode)
{
freezable_schedule_unsafe();
if (signal_pending_state(mode, current))
return -ERESTARTSYS;
return 0;
}
EXPORT_SYMBOL_GPL(nfs_wait_bit_killable);
/**
* 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)
{
#ifdef CONFIG_COMPAT
compat_ulong_t ino;
#else
unsigned long ino;
#endif
if (enable_ino64)
return fileid;
ino = fileid;
if (sizeof(ino) < sizeof(fileid))
ino ^= fileid >> (sizeof(fileid)-sizeof(ino)) * 8;
return ino;
}
int nfs_drop_inode(struct inode *inode)
{
return NFS_STALE(inode) || generic_drop_inode(inode);
}
EXPORT_SYMBOL_GPL(nfs_drop_inode);
void nfs_clear_inode(struct inode *inode)
{
/*
* The following should never happen...
*/
WARN_ON_ONCE(nfs_have_writebacks(inode));
WARN_ON_ONCE(!list_empty(&NFS_I(inode)->open_files));
nfs_zap_acl_cache(inode);
nfs_access_zap_cache(inode);
nfs_fscache_clear_inode(inode);
}
EXPORT_SYMBOL_GPL(nfs_clear_inode);
void nfs_evict_inode(struct inode *inode)
{
truncate_inode_pages_final(&inode->i_data);
clear_inode(inode);
nfs_clear_inode(inode);
}
int nfs_sync_inode(struct inode *inode)
{
nfs_inode_dio_wait(inode);
return nfs_wb_all(inode);
}
EXPORT_SYMBOL_GPL(nfs_sync_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;
}
static void nfs_set_cache_invalid(struct inode *inode, unsigned long flags)
{
struct nfs_inode *nfsi = NFS_I(inode);
if (inode->i_mapping->nrpages == 0)
flags &= ~NFS_INO_INVALID_DATA;
nfsi->cache_validity |= flags;
if (flags & NFS_INO_INVALID_DATA)
nfs_fscache_invalidate(inode);
}
/*
* 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_I(inode)->cookieverf, 0, sizeof(NFS_I(inode)->cookieverf));
if (S_ISREG(mode) || S_ISDIR(mode) || S_ISLNK(mode)) {
nfs_set_cache_invalid(inode, NFS_INO_INVALID_ATTR
| NFS_INO_INVALID_DATA
| NFS_INO_INVALID_ACCESS
| NFS_INO_INVALID_ACL
| NFS_INO_REVAL_PAGECACHE);
} else
nfs_set_cache_invalid(inode, NFS_INO_INVALID_ATTR
| NFS_INO_INVALID_ACCESS
| NFS_INO_INVALID_ACL
| NFS_INO_REVAL_PAGECACHE);
nfs_zap_label_cache_locked(nfsi);
}
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_set_cache_invalid(inode, 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);
}
EXPORT_SYMBOL_GPL(nfs_zap_acl_cache);
void nfs_invalidate_atime(struct inode *inode)
{
spin_lock(&inode->i_lock);
nfs_set_cache_invalid(inode, NFS_INO_INVALID_ATIME);
spin_unlock(&inode->i_lock);
}
EXPORT_SYMBOL_GPL(nfs_invalidate_atime);
/*
* 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 ((S_IFMT & inode->i_mode) != (S_IFMT & fattr->mode))
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;
}
#ifdef CONFIG_NFS_V4_SECURITY_LABEL
static void nfs_clear_label_invalid(struct inode *inode)
{
spin_lock(&inode->i_lock);
NFS_I(inode)->cache_validity &= ~NFS_INO_INVALID_LABEL;
spin_unlock(&inode->i_lock);
}
void nfs_setsecurity(struct inode *inode, struct nfs_fattr *fattr,
struct nfs4_label *label)
{
int error;
if (label == NULL)
return;
if ((fattr->valid & NFS_ATTR_FATTR_V4_SECURITY_LABEL) && inode->i_security) {
error = security_inode_notifysecctx(inode, label->label,
label->len);
if (error)
printk(KERN_ERR "%s() %s %d "
"security_inode_notifysecctx() %d\n",
__func__,
(char *)label->label,
label->len, error);
nfs_clear_label_invalid(inode);
}
}
struct nfs4_label *nfs4_label_alloc(struct nfs_server *server, gfp_t flags)
{
struct nfs4_label *label = NULL;
int minor_version = server->nfs_client->cl_minorversion;
if (minor_version < 2)
return label;
if (!(server->caps & NFS_CAP_SECURITY_LABEL))
return label;
label = kzalloc(sizeof(struct nfs4_label), flags);
if (label == NULL)
return ERR_PTR(-ENOMEM);
label->label = kzalloc(NFS4_MAXLABELLEN, flags);
if (label->label == NULL) {
kfree(label);
return ERR_PTR(-ENOMEM);
}
label->len = NFS4_MAXLABELLEN;
return label;
}
EXPORT_SYMBOL_GPL(nfs4_label_alloc);
#else
void nfs_setsecurity(struct inode *inode, struct nfs_fattr *fattr,
struct nfs4_label *label)
{
}
#endif
EXPORT_SYMBOL_GPL(nfs_setsecurity);
/*
* 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 nfs4_label *label)
{
struct nfs_find_desc desc = {
.fh = fh,
.fattr = fattr
};
struct inode *inode = ERR_PTR(-ENOENT);
unsigned long hash;
nfs_attr_check_mountpoint(sb, fattr);
if (nfs_attr_use_mounted_on_fileid(fattr))
fattr->fileid = fattr->mounted_on_fileid;
else 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))
nfs_set_cache_invalid(inode, NFS_INO_INVALID_ATTR);
/* 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_SB(sb)->nfs_client->rpc_ops->file_ops;
inode->i_data.a_ops = &nfs_file_aops;
} 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;
inode->i_data.a_ops = &nfs_dir_aops;
/* Deal with crossing mountpoints */
if (fattr->valid & NFS_ATTR_FATTR_MOUNTPOINT ||
fattr->valid & NFS_ATTR_FATTR_V4_REFERRAL) {
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;
inode->i_flags |= S_AUTOMOUNT;
}
} 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));
inode->i_version = 0;
inode->i_size = 0;
clear_nlink(inode);
inode->i_uid = make_kuid(&init_user_ns, -2);
inode->i_gid = make_kgid(&init_user_ns, -2);
inode->i_blocks = 0;
memset(nfsi->cookieverf, 0, sizeof(nfsi->cookieverf));
nfsi->write_io = 0;
nfsi->read_io = 0;
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))
nfs_set_cache_invalid(inode, 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))
nfs_set_cache_invalid(inode, NFS_INO_INVALID_ATTR);
if (fattr->valid & NFS_ATTR_FATTR_CTIME)
inode->i_ctime = fattr->ctime;
else if (nfs_server_capable(inode, NFS_CAP_CTIME))
nfs_set_cache_invalid(inode, NFS_INO_INVALID_ATTR);
if (fattr->valid & NFS_ATTR_FATTR_CHANGE)
inode->i_version = fattr->change_attr;
else
nfs_set_cache_invalid(inode, NFS_INO_INVALID_ATTR
| NFS_INO_REVAL_PAGECACHE);
if (fattr->valid & NFS_ATTR_FATTR_SIZE)
inode->i_size = nfs_size_to_loff_t(fattr->size);
else
nfs_set_cache_invalid(inode, NFS_INO_INVALID_ATTR
| NFS_INO_REVAL_PAGECACHE);
if (fattr->valid & NFS_ATTR_FATTR_NLINK)
set_nlink(inode, fattr->nlink);
else if (nfs_server_capable(inode, NFS_CAP_NLINK))
nfs_set_cache_invalid(inode, 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))
nfs_set_cache_invalid(inode, NFS_INO_INVALID_ATTR);
if (fattr->valid & NFS_ATTR_FATTR_GROUP)
inode->i_gid = fattr->gid;
else if (nfs_server_capable(inode, NFS_CAP_OWNER_GROUP))
nfs_set_cache_invalid(inode, NFS_INO_INVALID_ATTR);
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);
}
nfs_setsecurity(inode, fattr, label);
nfsi->attrtimeo = NFS_MINATTRTIMEO(inode);
nfsi->attrtimeo_timestamp = now;
nfsi->access_cache = RB_ROOT;
nfs_fscache_init_inode(inode);
unlock_new_inode(inode);
} else
nfs_refresh_inode(inode, fattr);
dprintk("NFS: nfs_fhget(%s/%Lu fh_crc=0x%08x ct=%d)\n",
inode->i_sb->s_id,
(unsigned long long)NFS_FILEID(inode),
nfs_display_fhandle_hash(fh),
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;
}
EXPORT_SYMBOL_GPL(nfs_fhget);
#define NFS_VALID_ATTRS (ATTR_MODE|ATTR_UID|ATTR_GID|ATTR_SIZE|ATTR_ATIME|ATTR_ATIME_SET|ATTR_MTIME|ATTR_MTIME_SET|ATTR_FILE|ATTR_OPEN)
int
nfs_setattr(struct dentry *dentry, struct iattr *attr)
{
struct inode *inode = d_inode(dentry);
struct nfs_fattr *fattr;
int error = 0;
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) {
BUG_ON(!S_ISREG(inode->i_mode));
error = inode_newsize_ok(inode, attr->ia_size);
if (error)
return error;
if (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|ATTR_OPEN)) == 0)
return 0;
trace_nfs_setattr_enter(inode);
/* Write all dirty data */
if (S_ISREG(inode->i_mode))
nfs_sync_inode(inode);
fattr = nfs_alloc_fattr();
if (fattr == NULL) {
error = -ENOMEM;
goto out;
}
/*
* Return any delegations if we're going to change ACLs
*/
if ((attr->ia_valid & (ATTR_MODE|ATTR_UID|ATTR_GID)) != 0)
NFS_PROTO(inode)->return_delegation(inode);
error = NFS_PROTO(inode)->setattr(dentry, fattr, attr);
if (error == 0)
error = nfs_refresh_inode(inode, fattr);
nfs_free_fattr(fattr);
out:
trace_nfs_setattr_exit(inode, error);
return error;
}
EXPORT_SYMBOL_GPL(nfs_setattr);
/**
* 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.
* Note: must be called with inode->i_lock held!
*/
static int nfs_vmtruncate(struct inode * inode, loff_t offset)
{
int err;
err = inode_newsize_ok(inode, offset);
if (err)
goto out;
i_size_write(inode, offset);
/* Optimisation */
if (offset == 0)
NFS_I(inode)->cache_validity &= ~NFS_INO_INVALID_DATA;
spin_unlock(&inode->i_lock);
truncate_pagecache(inode, offset);
spin_lock(&inode->i_lock);
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,
struct nfs_fattr *fattr)
{
/* Barrier: bump the attribute generation count. */
nfs_fattr_set_barrier(fattr);
spin_lock(&inode->i_lock);
NFS_I(inode)->attr_gencount = fattr->gencount;
if ((attr->ia_valid & (ATTR_MODE|ATTR_UID|ATTR_GID)) != 0) {
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_set_cache_invalid(inode, NFS_INO_INVALID_ACCESS
| NFS_INO_INVALID_ACL);
}
if ((attr->ia_valid & ATTR_SIZE) != 0) {
nfs_inc_stats(inode, NFSIOS_SETATTRTRUNC);
nfs_vmtruncate(inode, attr->ia_size);
}
if (fattr->valid)
nfs_update_inode(inode, fattr);
else
NFS_I(inode)->cache_validity |= NFS_INO_INVALID_ATTR;
spin_unlock(&inode->i_lock);
}
EXPORT_SYMBOL_GPL(nfs_setattr_update_inode);
static void nfs_request_parent_use_readdirplus(struct dentry *dentry)
{
struct dentry *parent;
parent = dget_parent(dentry);
nfs_force_use_readdirplus(d_inode(parent));
dput(parent);
}
static bool nfs_need_revalidate_inode(struct inode *inode)
{
if (NFS_I(inode)->cache_validity &
(NFS_INO_INVALID_ATTR|NFS_INO_INVALID_LABEL))
return true;
if (nfs_attribute_cache_expired(inode))
return true;
return false;
}
int nfs_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
{
struct inode *inode = d_inode(dentry);
int need_atime = NFS_I(inode)->cache_validity & NFS_INO_INVALID_ATIME;
int err = 0;
trace_nfs_getattr_enter(inode);
/* Flush out writes to the server in order to update c/mtime. */
if (S_ISREG(inode->i_mode)) {
mutex_lock(&inode->i_mutex);
err = nfs_sync_inode(inode);
mutex_unlock(&inode->i_mutex);
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 || nfs_need_revalidate_inode(inode)) {
struct nfs_server *server = NFS_SERVER(inode);
if (server->caps & NFS_CAP_READDIRPLUS)
nfs_request_parent_use_readdirplus(dentry);
err = __nfs_revalidate_inode(server, inode);
}
if (!err) {
generic_fillattr(inode, stat);
stat->ino = nfs_compat_user_ino64(NFS_FILEID(inode));
if (S_ISDIR(inode->i_mode))
stat->blksize = NFS_SERVER(inode)->dtsize;
}
out:
trace_nfs_getattr_exit(inode, err);
return err;
}
EXPORT_SYMBOL_GPL(nfs_getattr);
static void nfs_init_lock_context(struct nfs_lock_context *l_ctx)
{
atomic_set(&l_ctx->count, 1);
l_ctx->lockowner.l_owner = current->files;
l_ctx->lockowner.l_pid = current->tgid;
INIT_LIST_HEAD(&l_ctx->list);
nfs_iocounter_init(&l_ctx->io_count);
}
static struct nfs_lock_context *__nfs_find_lock_context(struct nfs_open_context *ctx)
{
struct nfs_lock_context *head = &ctx->lock_context;
struct nfs_lock_context *pos = head;
do {
if (pos->lockowner.l_owner != current->files)
continue;
if (pos->lockowner.l_pid != current->tgid)
continue;
atomic_inc(&pos->count);
return pos;
} while ((pos = list_entry(pos->list.next, typeof(*pos), list)) != head);
return NULL;
}
struct nfs_lock_context *nfs_get_lock_context(struct nfs_open_context *ctx)
{
struct nfs_lock_context *res, *new = NULL;
struct inode *inode = d_inode(ctx->dentry);
spin_lock(&inode->i_lock);
res = __nfs_find_lock_context(ctx);
if (res == NULL) {
spin_unlock(&inode->i_lock);
new = kmalloc(sizeof(*new), GFP_KERNEL);
if (new == NULL)
return ERR_PTR(-ENOMEM);
nfs_init_lock_context(new);
spin_lock(&inode->i_lock);
res = __nfs_find_lock_context(ctx);
if (res == NULL) {
list_add_tail(&new->list, &ctx->lock_context.list);
new->open_context = ctx;
res = new;
new = NULL;
}
}
spin_unlock(&inode->i_lock);
kfree(new);
return res;
}
EXPORT_SYMBOL_GPL(nfs_get_lock_context);
void nfs_put_lock_context(struct nfs_lock_context *l_ctx)
{
struct nfs_open_context *ctx = l_ctx->open_context;
struct inode *inode = d_inode(ctx->dentry);
if (!atomic_dec_and_lock(&l_ctx->count, &inode->i_lock))
return;
list_del(&l_ctx->list);
spin_unlock(&inode->i_lock);
kfree(l_ctx);
}
EXPORT_SYMBOL_GPL(nfs_put_lock_context);
/**
* nfs_close_context - Common close_context() routine NFSv2/v3
* @ctx: pointer to context
* @is_sync: is this a synchronous close
*
* Ensure that the attributes are up to date if we're mounted
* with close-to-open semantics and we have cached data that will
* need to be revalidated on open.
*/
void nfs_close_context(struct nfs_open_context *ctx, int is_sync)
{
struct nfs_inode *nfsi;
struct inode *inode;
struct nfs_server *server;
if (!(ctx->mode & FMODE_WRITE))
return;
if (!is_sync)
return;
inode = d_inode(ctx->dentry);
nfsi = NFS_I(inode);
if (inode->i_mapping->nrpages == 0)
return;
if (nfsi->cache_validity & NFS_INO_INVALID_DATA)
return;
if (!list_empty(&nfsi->open_files))
return;
server = NFS_SERVER(inode);
if (server->flags & NFS_MOUNT_NOCTO)
return;
nfs_revalidate_inode(server, inode);
}
EXPORT_SYMBOL_GPL(nfs_close_context);
struct nfs_open_context *alloc_nfs_open_context(struct dentry *dentry, fmode_t f_mode)
{
struct nfs_open_context *ctx;
struct rpc_cred *cred = rpc_lookup_cred();
if (IS_ERR(cred))
return ERR_CAST(cred);
ctx = kmalloc(sizeof(*ctx), GFP_KERNEL);
if (!ctx) {
put_rpccred(cred);
return ERR_PTR(-ENOMEM);
}
nfs_sb_active(dentry->d_sb);
ctx->dentry = dget(dentry);
ctx->cred = cred;
ctx->state = NULL;
ctx->mode = f_mode;
ctx->flags = 0;
ctx->error = 0;
nfs_init_lock_context(&ctx->lock_context);
ctx->lock_context.open_context = ctx;
INIT_LIST_HEAD(&ctx->list);
ctx->mdsthreshold = NULL;
return ctx;
}
EXPORT_SYMBOL_GPL(alloc_nfs_open_context);
struct nfs_open_context *get_nfs_open_context(struct nfs_open_context *ctx)
{
if (ctx != NULL)
atomic_inc(&ctx->lock_context.count);
return ctx;
}
EXPORT_SYMBOL_GPL(get_nfs_open_context);
static void __put_nfs_open_context(struct nfs_open_context *ctx, int is_sync)
{
struct inode *inode = d_inode(ctx->dentry);
struct super_block *sb = ctx->dentry->d_sb;
if (!list_empty(&ctx->list)) {
if (!atomic_dec_and_lock(&ctx->lock_context.count, &inode->i_lock))
return;
list_del(&ctx->list);
spin_unlock(&inode->i_lock);
} else if (!atomic_dec_and_test(&ctx->lock_context.count))
return;
if (inode != NULL)
NFS_PROTO(inode)->close_context(ctx, is_sync);
if (ctx->cred != NULL)
put_rpccred(ctx->cred);
dput(ctx->dentry);
nfs_sb_deactive(sb);
kfree(ctx->mdsthreshold);
kfree(ctx);
}
void put_nfs_open_context(struct nfs_open_context *ctx)
{
__put_nfs_open_context(ctx, 0);
}
EXPORT_SYMBOL_GPL(put_nfs_open_context);
static void put_nfs_open_context_sync(struct nfs_open_context *ctx)
{
__put_nfs_open_context(ctx, 1);
}
/*
* Ensure that mmap has a recent RPC credential for use when writing out
* shared pages
*/
void nfs_inode_attach_open_context(struct nfs_open_context *ctx)
{
struct inode *inode = d_inode(ctx->dentry);
struct nfs_inode *nfsi = NFS_I(inode);
spin_lock(&inode->i_lock);
list_add(&ctx->list, &nfsi->open_files);
spin_unlock(&inode->i_lock);
}
EXPORT_SYMBOL_GPL(nfs_inode_attach_open_context);
void nfs_file_set_open_context(struct file *filp, struct nfs_open_context *ctx)
{
filp->private_data = get_nfs_open_context(ctx);
if (list_empty(&ctx->list))
nfs_inode_attach_open_context(ctx);
}
EXPORT_SYMBOL_GPL(nfs_file_set_open_context);
/*
* 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 & (FMODE_READ|FMODE_WRITE)) != mode)
continue;
ctx = get_nfs_open_context(pos);
break;
}
spin_unlock(&inode->i_lock);
return ctx;
}
void nfs_file_clear_open_context(struct file *filp)
{
struct nfs_open_context *ctx = nfs_file_open_context(filp);
if (ctx) {
struct inode *inode = d_inode(ctx->dentry);
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_sync(ctx);
}
}
/*
* These allocate and release file read/write context information.
*/
int nfs_open(struct inode *inode, struct file *filp)
{
struct nfs_open_context *ctx;
ctx = alloc_nfs_open_context(filp->f_path.dentry, filp->f_mode);
if (IS_ERR(ctx))
return PTR_ERR(ctx);
nfs_file_set_open_context(filp, ctx);
put_nfs_open_context(ctx);
nfs_fscache_open_file(inode, 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 nfs4_label *label = NULL;
struct nfs_fattr *fattr = NULL;
struct nfs_inode *nfsi = NFS_I(inode);
dfprintk(PAGECACHE, "NFS: revalidating (%s/%Lu)\n",
inode->i_sb->s_id, (unsigned long long)NFS_FILEID(inode));
trace_nfs_revalidate_inode_enter(inode);
if (is_bad_inode(inode))
goto out;
if (NFS_STALE(inode))
goto out;
status = -ENOMEM;
fattr = nfs_alloc_fattr();
if (fattr == NULL)
goto out;
nfs_inc_stats(inode, NFSIOS_INODEREVALIDATE);
label = nfs4_label_alloc(NFS_SERVER(inode), GFP_KERNEL);
if (IS_ERR(label)) {
status = PTR_ERR(label);
goto out;
}
status = NFS_PROTO(inode)->getattr(server, NFS_FH(inode), fattr, label);
if (status != 0) {
dfprintk(PAGECACHE, "nfs_revalidate_inode: (%s/%Lu) getattr failed, error=%d\n",
inode->i_sb->s_id,
(unsigned 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 err_out;
}
status = nfs_refresh_inode(inode, fattr);
if (status) {
dfprintk(PAGECACHE, "nfs_revalidate_inode: (%s/%Lu) refresh failed, error=%d\n",
inode->i_sb->s_id,
(unsigned long long)NFS_FILEID(inode), status);
goto err_out;
}
if (nfsi->cache_validity & NFS_INO_INVALID_ACL)
nfs_zap_acl_cache(inode);
nfs_setsecurity(inode, fattr, label);
dfprintk(PAGECACHE, "NFS: (%s/%Lu) revalidation complete\n",
inode->i_sb->s_id,
(unsigned long long)NFS_FILEID(inode));
err_out:
nfs4_label_free(label);
out:
nfs_free_fattr(fattr);
trace_nfs_revalidate_inode_exit(inode, status);
return status;
}
int nfs_attribute_timeout(struct inode *inode)
{
struct nfs_inode *nfsi = NFS_I(inode);
return !time_in_range_open(jiffies, nfsi->read_cache_jiffies, nfsi->read_cache_jiffies + nfsi->attrtimeo);
}
int nfs_attribute_cache_expired(struct inode *inode)
{
if (nfs_have_delegated_attributes(inode))
return 0;
return nfs_attribute_timeout(inode);
}
/**
* 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_need_revalidate_inode(inode))
return NFS_STALE(inode) ? -ESTALE : 0;
return __nfs_revalidate_inode(server, inode);
}
EXPORT_SYMBOL_GPL(nfs_revalidate_inode);
int nfs_revalidate_inode_rcu(struct nfs_server *server, struct inode *inode)
{
if (!(NFS_I(inode)->cache_validity &
(NFS_INO_INVALID_ATTR|NFS_INO_INVALID_LABEL))
&& !nfs_attribute_cache_expired(inode))
return NFS_STALE(inode) ? -ESTALE : 0;
return -ECHILD;
}
static int nfs_invalidate_mapping(struct inode *inode, struct address_space *mapping)
{
struct nfs_inode *nfsi = NFS_I(inode);
int ret;
if (mapping->nrpages != 0) {
if (S_ISREG(inode->i_mode)) {
unmap_mapping_range(mapping, 0, 0, 0);
ret = nfs_sync_mapping(mapping);
if (ret < 0)
return ret;
}
ret = invalidate_inode_pages2(mapping);
if (ret < 0)
return ret;
}
if (S_ISDIR(inode->i_mode)) {
spin_lock(&inode->i_lock);
memset(nfsi->cookieverf, 0, sizeof(nfsi->cookieverf));
spin_unlock(&inode->i_lock);
}
nfs_inc_stats(inode, NFSIOS_DATAINVALIDATE);
nfs_fscache_wait_on_invalidate(inode);
dfprintk(PAGECACHE, "NFS: (%s/%Lu) data cache invalidated\n",
inode->i_sb->s_id,
(unsigned long long)NFS_FILEID(inode));
return 0;
}
static bool nfs_mapping_need_revalidate_inode(struct inode *inode)
{
if (nfs_have_delegated_attributes(inode))
return false;
return (NFS_I(inode)->cache_validity & NFS_INO_REVAL_PAGECACHE)
|| nfs_attribute_timeout(inode)
|| NFS_STALE(inode);
}
/**
* __nfs_revalidate_mapping - Revalidate the pagecache
* @inode - pointer to host inode
* @mapping - pointer to mapping
* @may_lock - take inode->i_mutex?
*/
static int __nfs_revalidate_mapping(struct inode *inode,
struct address_space *mapping,
bool may_lock)
{
struct nfs_inode *nfsi = NFS_I(inode);
unsigned long *bitlock = &nfsi->flags;
int ret = 0;
/* swapfiles are not supposed to be shared. */
if (IS_SWAPFILE(inode))
goto out;
if (nfs_mapping_need_revalidate_inode(inode)) {
ret = __nfs_revalidate_inode(NFS_SERVER(inode), inode);
if (ret < 0)
goto out;
}
/*
* We must clear NFS_INO_INVALID_DATA first to ensure that
* invalidations that come in while we're shooting down the mappings
* are respected. But, that leaves a race window where one revalidator
* can clear the flag, and then another checks it before the mapping
* gets invalidated. Fix that by serializing access to this part of
* the function.
*
* At the same time, we need to allow other tasks to see whether we
* might be in the middle of invalidating the pages, so we only set
* the bit lock here if it looks like we're going to be doing that.
*/
for (;;) {
ret = wait_on_bit_action(bitlock, NFS_INO_INVALIDATING,
nfs_wait_bit_killable, TASK_KILLABLE);
if (ret)
goto out;
spin_lock(&inode->i_lock);
if (test_bit(NFS_INO_INVALIDATING, bitlock)) {
spin_unlock(&inode->i_lock);
continue;
}
if (nfsi->cache_validity & NFS_INO_INVALID_DATA)
break;
spin_unlock(&inode->i_lock);
goto out;
}
set_bit(NFS_INO_INVALIDATING, bitlock);
smp_wmb();
nfsi->cache_validity &= ~NFS_INO_INVALID_DATA;
spin_unlock(&inode->i_lock);
trace_nfs_invalidate_mapping_enter(inode);
if (may_lock) {
mutex_lock(&inode->i_mutex);
ret = nfs_invalidate_mapping(inode, mapping);
mutex_unlock(&inode->i_mutex);
} else
ret = nfs_invalidate_mapping(inode, mapping);
trace_nfs_invalidate_mapping_exit(inode, ret);
clear_bit_unlock(NFS_INO_INVALIDATING, bitlock);
smp_mb__after_atomic();
wake_up_bit(bitlock, NFS_INO_INVALIDATING);
out:
return ret;
}
/**
* 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)
{
return __nfs_revalidate_mapping(inode, mapping, false);
}
/**
* nfs_revalidate_mapping_protected - Revalidate the pagecache
* @inode - pointer to host inode
* @mapping - pointer to mapping
*
* Differs from nfs_revalidate_mapping() in that it grabs the inode->i_mutex
* while invalidating the mapping.
*/
int nfs_revalidate_mapping_protected(struct inode *inode, struct address_space *mapping)
{
return __nfs_revalidate_mapping(inode, mapping, true);
}
static unsigned long nfs_wcc_update_inode(struct inode *inode, struct nfs_fattr *fattr)
{
struct nfs_inode *nfsi = NFS_I(inode);
unsigned long ret = 0;
if ((fattr->valid & NFS_ATTR_FATTR_PRECHANGE)
&& (fattr->valid & NFS_ATTR_FATTR_CHANGE)
&& inode->i_version == fattr->pre_change_attr) {
inode->i_version = fattr->change_attr;
if (S_ISDIR(inode->i_mode))
nfs_set_cache_invalid(inode, NFS_INO_INVALID_DATA);
ret |= NFS_INO_INVALID_ATTR;
}
/* 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));
ret |= NFS_INO_INVALID_ATTR;
}
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))
nfs_set_cache_invalid(inode, NFS_INO_INVALID_DATA);
ret |= NFS_INO_INVALID_ATTR;
}
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->nrequests == 0) {
i_size_write(inode, nfs_size_to_loff_t(fattr->size));
ret |= NFS_INO_INVALID_ATTR;
}
return ret;
}
/**
* 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;
if (nfs_have_delegated_attributes(inode))
return 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 &&
inode->i_version != 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;
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)
invalid |= NFS_INO_INVALID_ATTR|NFS_INO_REVAL_PAGECACHE;
}
if (nfsi->nrequests != 0)
invalid &= ~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) && !uid_eq(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) && !gid_eq(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)
nfs_set_cache_invalid(inode, invalid);
nfsi->read_cache_jiffies = fattr->time_start;
return 0;
}
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);
}
EXPORT_SYMBOL_GPL(nfs_inc_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();
fattr->owner_name = NULL;
fattr->group_name = NULL;
}
EXPORT_SYMBOL_GPL(nfs_fattr_init);
/**
* nfs_fattr_set_barrier
* @fattr: attributes
*
* Used to set a barrier after an attribute was updated. This
* barrier ensures that older attributes from RPC calls that may
* have raced with our update cannot clobber these new values.
* Note that you are still responsible for ensuring that other
* operations which change the attribute on the server do not
* collide.
*/
void nfs_fattr_set_barrier(struct nfs_fattr *fattr)
{
fattr->gencount = nfs_inc_attr_generation_counter();
}
struct nfs_fattr *nfs_alloc_fattr(void)
{
struct nfs_fattr *fattr;
fattr = kmalloc(sizeof(*fattr), GFP_NOFS);
if (fattr != NULL)
nfs_fattr_init(fattr);
return fattr;
}
EXPORT_SYMBOL_GPL(nfs_alloc_fattr);
struct nfs_fh *nfs_alloc_fhandle(void)
{
struct nfs_fh *fh;
fh = kmalloc(sizeof(struct nfs_fh), GFP_NOFS);
if (fh != NULL)
fh->size = 0;
return fh;
}
EXPORT_SYMBOL_GPL(nfs_alloc_fhandle);
#ifdef NFS_DEBUG
/*
* _nfs_display_fhandle_hash - calculate the crc32 hash for the filehandle
* in the same way that wireshark does
*
* @fh: file handle
*
* For debugging only.
*/
u32 _nfs_display_fhandle_hash(const struct nfs_fh *fh)
{
/* wireshark uses 32-bit AUTODIN crc and does a bitwise
* not on the result */
return nfs_fhandle_hash(fh);
}
EXPORT_SYMBOL_GPL(_nfs_display_fhandle_hash);
/*
* _nfs_display_fhandle - display an NFS file handle on the console
*
* @fh: file handle to display
* @caption: display caption
*
* For debugging only.
*/
void _nfs_display_fhandle(const struct nfs_fh *fh, const char *caption)
{
unsigned short i;
if (fh == NULL || fh->size == 0) {
printk(KERN_DEFAULT "%s at %p is empty\n", caption, fh);
return;
}
printk(KERN_DEFAULT "%s at %p is %u bytes, crc: 0x%08x:\n",
caption, fh, fh->size, _nfs_display_fhandle_hash(fh));
for (i = 0; i < fh->size; i += 16) {
__be32 *pos = (__be32 *)&fh->data[i];
switch ((fh->size - i - 1) >> 2) {
case 0:
printk(KERN_DEFAULT " %08x\n",
be32_to_cpup(pos));
break;
case 1:
printk(KERN_DEFAULT " %08x %08x\n",
be32_to_cpup(pos), be32_to_cpup(pos + 1));
break;
case 2:
printk(KERN_DEFAULT " %08x %08x %08x\n",
be32_to_cpup(pos), be32_to_cpup(pos + 1),
be32_to_cpup(pos + 2));
break;
default:
printk(KERN_DEFAULT " %08x %08x %08x %08x\n",
be32_to_cpup(pos), be32_to_cpup(pos + 1),
be32_to_cpup(pos + 2), be32_to_cpup(pos + 3));
}
}
}
EXPORT_SYMBOL_GPL(_nfs_display_fhandle);
#endif
/**
* 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 ||
((long)nfsi->attr_gencount - (long)nfs_read_attr_generation_counter() > 0);
}
/*
* Don't trust the change_attribute, mtime, ctime or size if
* a pnfs LAYOUTCOMMIT is outstanding
*/
static void nfs_inode_attrs_handle_layoutcommit(struct inode *inode,
struct nfs_fattr *fattr)
{
if (pnfs_layoutcommit_outstanding(inode))
fattr->valid &= ~(NFS_ATTR_FATTR_CHANGE |
NFS_ATTR_FATTR_MTIME |
NFS_ATTR_FATTR_CTIME |
NFS_ATTR_FATTR_SIZE);
}
static int nfs_refresh_inode_locked(struct inode *inode, struct nfs_fattr *fattr)
{
int ret;
trace_nfs_refresh_inode_enter(inode);
nfs_inode_attrs_handle_layoutcommit(inode, fattr);
if (nfs_inode_attrs_need_update(inode, fattr))
ret = nfs_update_inode(inode, fattr);
else
ret = nfs_check_inode_attributes(inode, fattr);
trace_nfs_refresh_inode_exit(inode, ret);
return ret;
}
/**
* 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;
}
EXPORT_SYMBOL_GPL(nfs_refresh_inode);
static int nfs_post_op_update_inode_locked(struct inode *inode, struct nfs_fattr *fattr)
{
unsigned long invalid = NFS_INO_INVALID_ATTR|NFS_INO_REVAL_PAGECACHE;
/*
* Don't revalidate the pagecache if we hold a delegation, but do
* force an attribute update
*/
if (NFS_PROTO(inode)->have_delegation(inode, FMODE_READ))
invalid = NFS_INO_INVALID_ATTR|NFS_INO_REVAL_FORCED;
if (S_ISDIR(inode->i_mode))
invalid |= NFS_INO_INVALID_DATA;
nfs_set_cache_invalid(inode, invalid);
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
* unnecessary NFS requests and trips through nfs_update_inode().
*/
int nfs_post_op_update_inode(struct inode *inode, struct nfs_fattr *fattr)
{
int status;
spin_lock(&inode->i_lock);
nfs_fattr_set_barrier(fattr);
status = nfs_post_op_update_inode_locked(inode, fattr);
spin_unlock(&inode->i_lock);
return status;
}
EXPORT_SYMBOL_GPL(nfs_post_op_update_inode);
/**
* nfs_post_op_update_inode_force_wcc_locked - 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. Fake up
* weak cache consistency data, if none exist.
*
* This function is mainly designed to be used by the ->write_done() functions.
*/
int nfs_post_op_update_inode_force_wcc_locked(struct inode *inode, struct nfs_fattr *fattr)
{
int status;
/* Don't do a WCC update if these attributes are already stale */
if ((fattr->valid & NFS_ATTR_FATTR) == 0 ||
!nfs_inode_attrs_need_update(inode, fattr)) {
fattr->valid &= ~(NFS_ATTR_FATTR_PRECHANGE
| NFS_ATTR_FATTR_PRESIZE
| NFS_ATTR_FATTR_PREMTIME
| NFS_ATTR_FATTR_PRECTIME);
goto out_noforce;
}
if ((fattr->valid & NFS_ATTR_FATTR_CHANGE) != 0 &&
(fattr->valid & NFS_ATTR_FATTR_PRECHANGE) == 0) {
fattr->pre_change_attr = inode->i_version;
fattr->valid |= NFS_ATTR_FATTR_PRECHANGE;
}
if ((fattr->valid & NFS_ATTR_FATTR_CTIME) != 0 &&
(fattr->valid & NFS_ATTR_FATTR_PRECTIME) == 0) {
memcpy(&fattr->pre_ctime, &inode->i_ctime, sizeof(fattr->pre_ctime));
fattr->valid |= NFS_ATTR_FATTR_PRECTIME;
}
if ((fattr->valid & NFS_ATTR_FATTR_MTIME) != 0 &&
(fattr->valid & NFS_ATTR_FATTR_PREMTIME) == 0) {
memcpy(&fattr->pre_mtime, &inode->i_mtime, sizeof(fattr->pre_mtime));
fattr->valid |= NFS_ATTR_FATTR_PREMTIME;
}
if ((fattr->valid & NFS_ATTR_FATTR_SIZE) != 0 &&
(fattr->valid & NFS_ATTR_FATTR_PRESIZE) == 0) {
fattr->pre_size = i_size_read(inode);
fattr->valid |= NFS_ATTR_FATTR_PRESIZE;
}
out_noforce:
status = nfs_post_op_update_inode_locked(inode, fattr);
return status;
}
/**
* nfs_post_op_update_inode_force_wcc - 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. Fake up
* weak cache consistency data, if none exist.
*
* This function is mainly designed to be used by the ->write_done() functions.
*/
int nfs_post_op_update_inode_force_wcc(struct inode *inode, struct nfs_fattr *fattr)
{
int status;
spin_lock(&inode->i_lock);
nfs_fattr_set_barrier(fattr);
status = nfs_post_op_update_inode_force_wcc_locked(inode, fattr);
spin_unlock(&inode->i_lock);
return status;
}
EXPORT_SYMBOL_GPL(nfs_post_op_update_inode_force_wcc);
static inline bool nfs_fileid_valid(struct nfs_inode *nfsi,
struct nfs_fattr *fattr)
{
bool ret1 = true, ret2 = true;
if (fattr->valid & NFS_ATTR_FATTR_FILEID)
ret1 = (nfsi->fileid == fattr->fileid);
if (fattr->valid & NFS_ATTR_FATTR_MOUNTED_ON_FILEID)
ret2 = (nfsi->fileid == fattr->mounted_on_fileid);
return ret1 || ret2;
}
/*
* 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.
*/
static int nfs_update_inode(struct inode *inode, struct nfs_fattr *fattr)
{
struct nfs_server *server;
struct nfs_inode *nfsi = NFS_I(inode);
loff_t cur_isize, new_isize;
unsigned long invalid = 0;
unsigned long now = jiffies;
unsigned long save_cache_validity;
dfprintk(VFS, "NFS: %s(%s/%lu fh_crc=0x%08x ct=%d info=0x%x)\n",
__func__, inode->i_sb->s_id, inode->i_ino,
nfs_display_fhandle_hash(NFS_FH(inode)),
atomic_read(&inode->i_count), fattr->valid);
if (!nfs_fileid_valid(nfsi, fattr)) {
printk(KERN_ERR "NFS: server %s error: fileid changed\n"
"fsid %s: expected fileid 0x%Lx, got 0x%Lx\n",
NFS_SERVER(inode)->nfs_client->cl_hostname,
inode->i_sb->s_id, (long long)nfsi->fileid,
(long long)fattr->fileid);
goto out_err;
}
/*
* Make sure the inode's type hasn't changed.
*/
if ((fattr->valid & NFS_ATTR_FATTR_TYPE) && (inode->i_mode & S_IFMT) != (fattr->mode & S_IFMT)) {
/*
* Big trouble! The inode has become a different object.
*/
printk(KERN_DEBUG "NFS: %s: inode %lu mode changed, %07o to %07o\n",
__func__, inode->i_ino, inode->i_mode, fattr->mode);
goto out_err;
}
server = NFS_SERVER(inode);
/* Update the fsid? */
if (S_ISDIR(inode->i_mode) && (fattr->valid & NFS_ATTR_FATTR_FSID) &&
!nfs_fsid_equal(&server->fsid, &fattr->fsid) &&
!IS_AUTOMOUNT(inode))
server->fsid = fattr->fsid;
/*
* Update the read time so we don't revalidate too often.
*/
nfsi->read_cache_jiffies = fattr->time_start;
save_cache_validity = nfsi->cache_validity;
nfsi->cache_validity &= ~(NFS_INO_INVALID_ATTR
| NFS_INO_INVALID_ATIME
| NFS_INO_REVAL_FORCED
| NFS_INO_REVAL_PAGECACHE);
/* Do atomic weak cache consistency updates */
invalid |= nfs_wcc_update_inode(inode, fattr);
/* More cache consistency checks */
if (fattr->valid & NFS_ATTR_FATTR_CHANGE) {
if (inode->i_version != fattr->change_attr) {
dprintk("NFS: change_attr change on server for file %s/%ld\n",
inode->i_sb->s_id, inode->i_ino);
invalid |= NFS_INO_INVALID_ATTR
| NFS_INO_INVALID_DATA
| NFS_INO_INVALID_ACCESS
| NFS_INO_INVALID_ACL;
if (S_ISDIR(inode->i_mode))
nfs_force_lookup_revalidate(inode);
inode->i_version = fattr->change_attr;
}
} else
nfsi->cache_validity |= save_cache_validity;
if (fattr->valid & NFS_ATTR_FATTR_MTIME) {
memcpy(&inode->i_mtime, &fattr->mtime, sizeof(inode->i_mtime));
} else if (server->caps & NFS_CAP_MTIME)
nfsi->cache_validity |= save_cache_validity &
(NFS_INO_INVALID_ATTR
| NFS_INO_REVAL_FORCED);
if (fattr->valid & NFS_ATTR_FATTR_CTIME) {
memcpy(&inode->i_ctime, &fattr->ctime, sizeof(inode->i_ctime));
} else if (server->caps & NFS_CAP_CTIME)
nfsi->cache_validity |= save_cache_validity &
(NFS_INO_INVALID_ATTR
| NFS_INO_REVAL_FORCED);
/* Check if our cached file size is stale */
if (fattr->valid & NFS_ATTR_FATTR_SIZE) {
new_isize = nfs_size_to_loff_t(fattr->size);
cur_isize = i_size_read(inode);
if (new_isize != cur_isize) {
/* Do we perhaps have any outstanding writes, or has
* the file grown beyond our last write? */
if ((nfsi->nrequests == 0) || new_isize > cur_isize) {
i_size_write(inode, new_isize);
invalid |= NFS_INO_INVALID_ATTR|NFS_INO_INVALID_DATA;
}
dprintk("NFS: isize change on server for file %s/%ld "
"(%Ld to %Ld)\n",
inode->i_sb->s_id,
inode->i_ino,
(long long)cur_isize,
(long long)new_isize);
}
} else
nfsi->cache_validity |= save_cache_validity &
(NFS_INO_INVALID_ATTR
| NFS_INO_REVAL_PAGECACHE
| NFS_INO_REVAL_FORCED);
if (fattr->valid & NFS_ATTR_FATTR_ATIME)
memcpy(&inode->i_atime, &fattr->atime, sizeof(inode->i_atime));
else if (server->caps & NFS_CAP_ATIME)
nfsi->cache_validity |= save_cache_validity &
(NFS_INO_INVALID_ATIME
| NFS_INO_REVAL_FORCED);
if (fattr->valid & NFS_ATTR_FATTR_MODE) {
if ((inode->i_mode & S_IALLUGO) != (fattr->mode & S_IALLUGO)) {
umode_t newmode = inode->i_mode & S_IFMT;
newmode |= fattr->mode & S_IALLUGO;
inode->i_mode = newmode;
invalid |= NFS_INO_INVALID_ATTR|NFS_INO_INVALID_ACCESS|NFS_INO_INVALID_ACL;
}
} else if (server->caps & NFS_CAP_MODE)
nfsi->cache_validity |= save_cache_validity &
(NFS_INO_INVALID_ATTR
| NFS_INO_INVALID_ACCESS
| NFS_INO_INVALID_ACL
| NFS_INO_REVAL_FORCED);
if (fattr->valid & NFS_ATTR_FATTR_OWNER) {
if (!uid_eq(inode->i_uid, fattr->uid)) {
invalid |= NFS_INO_INVALID_ATTR|NFS_INO_INVALID_ACCESS|NFS_INO_INVALID_ACL;
inode->i_uid = fattr->uid;
}
} else if (server->caps & NFS_CAP_OWNER)
nfsi->cache_validity |= save_cache_validity &
(NFS_INO_INVALID_ATTR
| NFS_INO_INVALID_ACCESS
| NFS_INO_INVALID_ACL
| NFS_INO_REVAL_FORCED);
if (fattr->valid & NFS_ATTR_FATTR_GROUP) {
if (!gid_eq(inode->i_gid, fattr->gid)) {
invalid |= NFS_INO_INVALID_ATTR|NFS_INO_INVALID_ACCESS|NFS_INO_INVALID_ACL;
inode->i_gid = fattr->gid;
}
} else if (server->caps & NFS_CAP_OWNER_GROUP)
nfsi->cache_validity |= save_cache_validity &
(NFS_INO_INVALID_ATTR
| NFS_INO_INVALID_ACCESS
| NFS_INO_INVALID_ACL
| NFS_INO_REVAL_FORCED);
if (fattr->valid & NFS_ATTR_FATTR_NLINK) {
if (inode->i_nlink != fattr->nlink) {
invalid |= NFS_INO_INVALID_ATTR;
if (S_ISDIR(inode->i_mode))
invalid |= NFS_INO_INVALID_DATA;
set_nlink(inode, fattr->nlink);
}
} else if (server->caps & NFS_CAP_NLINK)
nfsi->cache_validity |= save_cache_validity &
(NFS_INO_INVALID_ATTR
| NFS_INO_REVAL_FORCED);
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);
}
if (fattr->valid & NFS_ATTR_FATTR_BLOCKS_USED)
inode->i_blocks = fattr->du.nfs2.blocks;
/* Update attrtimeo value if we're out of the unstable period */
if (invalid & NFS_INO_INVALID_ATTR) {
nfs_inc_stats(inode, NFSIOS_ATTRINVALIDATE);
nfsi->attrtimeo = NFS_MINATTRTIMEO(inode);
nfsi->attrtimeo_timestamp = now;
/* Set barrier to be more recent than all outstanding updates */
nfsi->attr_gencount = nfs_inc_attr_generation_counter();
} else {
if (!time_in_range_open(now, nfsi->attrtimeo_timestamp, nfsi->attrtimeo_timestamp + nfsi->attrtimeo)) {
if ((nfsi->attrtimeo <<= 1) > NFS_MAXATTRTIMEO(inode))
nfsi->attrtimeo = NFS_MAXATTRTIMEO(inode);
nfsi->attrtimeo_timestamp = now;
}
/* Set the barrier to be more recent than this fattr */
if ((long)fattr->gencount - (long)nfsi->attr_gencount > 0)
nfsi->attr_gencount = fattr->gencount;
}
/* Don't declare attrcache up to date if there were no attrs! */
if (fattr->valid != 0)
invalid &= ~NFS_INO_INVALID_ATTR;
/* Don't invalidate the data if we were to blame */
if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode)
|| S_ISLNK(inode->i_mode)))
invalid &= ~NFS_INO_INVALID_DATA;
if (!NFS_PROTO(inode)->have_delegation(inode, FMODE_READ) ||
(save_cache_validity & NFS_INO_REVAL_FORCED))
nfs_set_cache_invalid(inode, invalid);
return 0;
out_err:
/*
* 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);
return -ESTALE;
}
struct inode *nfs_alloc_inode(struct super_block *sb)
{
struct nfs_inode *nfsi;
nfsi = kmem_cache_alloc(nfs_inode_cachep, GFP_KERNEL);
if (!nfsi)
return NULL;
nfsi->flags = 0UL;
nfsi->cache_validity = 0UL;
#if IS_ENABLED(CONFIG_NFS_V4)
nfsi->nfs4_acl = NULL;
#endif /* CONFIG_NFS_V4 */
return &nfsi->vfs_inode;
}
EXPORT_SYMBOL_GPL(nfs_alloc_inode);
static void nfs_i_callback(struct rcu_head *head)
{
struct inode *inode = container_of(head, struct inode, i_rcu);
kmem_cache_free(nfs_inode_cachep, NFS_I(inode));
}
void nfs_destroy_inode(struct inode *inode)
{
call_rcu(&inode->i_rcu, nfs_i_callback);
}
EXPORT_SYMBOL_GPL(nfs_destroy_inode);
static inline void nfs4_init_once(struct nfs_inode *nfsi)
{
#if IS_ENABLED(CONFIG_NFS_V4)
INIT_LIST_HEAD(&nfsi->open_states);
nfsi->delegation = NULL;
init_rwsem(&nfsi->rwsem);
nfsi->layout = NULL;
#endif
}
static void init_once(void *foo)
{
struct nfs_inode *nfsi = (struct nfs_inode *) foo;
inode_init_once(&nfsi->vfs_inode);
INIT_LIST_HEAD(&nfsi->open_files);
INIT_LIST_HEAD(&nfsi->access_cache_entry_lru);
INIT_LIST_HEAD(&nfsi->access_cache_inode_lru);
INIT_LIST_HEAD(&nfsi->commit_info.list);
nfsi->nrequests = 0;
nfsi->commit_info.ncommit = 0;
atomic_set(&nfsi->commit_info.rpcs_out, 0);
atomic_set(&nfsi->silly_count, 1);
INIT_HLIST_HEAD(&nfsi->silly_list);
init_waitqueue_head(&nfsi->waitqueue);
nfs4_init_once(nfsi);
}
static int __init nfs_init_inodecache(void)
{
nfs_inode_cachep = kmem_cache_create("nfs_inode_cache",
sizeof(struct nfs_inode),
0, (SLAB_RECLAIM_ACCOUNT|
SLAB_MEM_SPREAD),
init_once);
if (nfs_inode_cachep == NULL)
return -ENOMEM;
return 0;
}
static void nfs_destroy_inodecache(void)
{
/*
* Make sure all delayed rcu free inodes are flushed before we
* destroy cache.
*/
rcu_barrier();
kmem_cache_destroy(nfs_inode_cachep);
}
struct workqueue_struct *nfsiod_workqueue;
EXPORT_SYMBOL_GPL(nfsiod_workqueue);
/*
* start up the nfsiod workqueue
*/
static int nfsiod_start(void)
{
struct workqueue_struct *wq;
dprintk("RPC: creating workqueue nfsiod\n");
wq = alloc_workqueue("nfsiod", WQ_MEM_RECLAIM, 0);
if (wq == NULL)
return -ENOMEM;
nfsiod_workqueue = wq;
return 0;
}
/*
* Destroy the nfsiod workqueue
*/
static void nfsiod_stop(void)
{
struct workqueue_struct *wq;
wq = nfsiod_workqueue;
if (wq == NULL)
return;
nfsiod_workqueue = NULL;
destroy_workqueue(wq);
}
int nfs_net_id;
EXPORT_SYMBOL_GPL(nfs_net_id);
static int nfs_net_init(struct net *net)
{
nfs_clients_init(net);
return nfs_fs_proc_net_init(net);
}
static void nfs_net_exit(struct net *net)
{
nfs_fs_proc_net_exit(net);
nfs_cleanup_cb_ident_idr(net);
}
static struct pernet_operations nfs_net_ops = {
.init = nfs_net_init,
.exit = nfs_net_exit,
.id = &nfs_net_id,
.size = sizeof(struct nfs_net),
};
/*
* Initialize NFS
*/
static int __init init_nfs_fs(void)
{
int err;
err = register_pernet_subsys(&nfs_net_ops);
if (err < 0)
goto out9;
err = nfs_fscache_register();
if (err < 0)
goto out8;
err = nfsiod_start();
if (err)
goto out7;
err = nfs_fs_proc_init();
if (err)
goto out6;
err = nfs_init_nfspagecache();
if (err)
goto out5;
err = nfs_init_inodecache();
if (err)
goto out4;
err = nfs_init_readpagecache();
if (err)
goto out3;
err = nfs_init_writepagecache();
if (err)
goto out2;
err = nfs_init_directcache();
if (err)
goto out1;
rpc_proc_register(&init_net, &nfs_rpcstat);
err = register_nfs_fs();
if (err)
goto out0;
return 0;
out0:
rpc_proc_unregister(&init_net, "nfs");
nfs_destroy_directcache();
out1:
nfs_destroy_writepagecache();
out2:
nfs_destroy_readpagecache();
out3:
nfs_destroy_inodecache();
out4:
nfs_destroy_nfspagecache();
out5:
nfs_fs_proc_exit();
out6:
nfsiod_stop();
out7:
nfs_fscache_unregister();
out8:
unregister_pernet_subsys(&nfs_net_ops);
out9:
return err;
}
static void __exit exit_nfs_fs(void)
{
nfs_destroy_directcache();
nfs_destroy_writepagecache();
nfs_destroy_readpagecache();
nfs_destroy_inodecache();
nfs_destroy_nfspagecache();
nfs_fscache_unregister();
unregister_pernet_subsys(&nfs_net_ops);
rpc_proc_unregister(&init_net, "nfs");
unregister_nfs_fs();
nfs_fs_proc_exit();
nfsiod_stop();
}
/* Not quite true; I just maintain it */
MODULE_AUTHOR("Olaf Kirch <okir@monad.swb.de>");
MODULE_LICENSE("GPL");
module_param(enable_ino64, bool, 0644);
module_init(init_nfs_fs)
module_exit(exit_nfs_fs)