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f044636d97
linux/fs/nfs/inode.c
Trond Myklebust f044636d97 NFS: Add attribute update barriers to nfs_setattr_update_inode() 
Ensure that other operations which raced with our setattr RPC call
cannot revert the file attribute changes that were made on the server.
To do so, we artificially bump the attribute generation counter on
the inode so that all calls to nfs_fattr_init() that precede ours
will be dropped.

The motivation for the patch came from Chuck Lever's reports of readaheads
racing with truncate operations and causing the file size to be reverted.

Reported-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Tested-by: Chuck Lever <chuck.lever@oracle.com>
2015-03-01 23:23:05 -05:00

1999 lines
54 KiB
C
Raw Blame History

/*
* 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)
{
if (fatal_signal_pending(current))
return -ERESTARTSYS;
freezable_schedule_unsafe();
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);
}
/**
* 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);
}
EXPORT_SYMBOL_GPL(nfs_zap_caches);
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 if (nfs_server_capable(inode, NFS_CAP_CHANGE_ATTR))
nfs_set_cache_invalid(inode, NFS_INO_INVALID_ATTR);
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 = dentry->d_inode;
struct nfs_fattr *fattr;
int error = -ENOMEM;
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) {
loff_t i_size;
BUG_ON(!S_ISREG(inode->i_mode));
i_size = i_size_read(inode);
if (attr->ia_size == i_size)
attr->ia_valid &= ~ATTR_SIZE;
else if (attr->ia_size < i_size && IS_SWAPFILE(inode))
return -ETXTBSY;
}
/* 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_inode_dio_wait(inode);
nfs_wb_all(inode);
}
fattr = nfs_alloc_fattr();
if (fattr == NULL)
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);
}
nfs_update_inode(inode, fattr);
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(parent->d_inode);
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 = dentry->d_inode;
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)) {
nfs_inode_dio_wait(inode);
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 || 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));
}
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 = ctx->dentry->d_inode;
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 = ctx->dentry->d_inode;
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
*
* 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->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);
}
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 = ctx->dentry->d_inode;
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);
/*
* 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 = ctx->dentry->d_inode;
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;
}
static void nfs_file_clear_open_context(struct file *filp)
{
struct nfs_open_context *ctx = nfs_file_open_context(filp);
if (ctx) {
struct inode *inode = ctx->dentry->d_inode;
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;
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;
}
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 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)) {
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
*/
int nfs_revalidate_mapping(struct inode *inode, struct address_space *mapping)
{
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);
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;
}
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 && nfsi->nrequests == 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) && !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 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();
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 ||
nfs_ctime_need_update(inode, fattr) ||
nfs_size_need_update(inode, fattr) ||
((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;
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);
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 - 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);
/* 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);
spin_unlock(&inode->i_lock);
return status;
}
EXPORT_SYMBOL_GPL(nfs_post_op_update_inode_force_wcc);
/*
* 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 ((fattr->valid & NFS_ATTR_FATTR_FILEID) && nfsi->fileid != fattr->fileid) {
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
| NFS_INO_REVAL_PAGECACHE;
if (S_ISDIR(inode->i_mode))
nfs_force_lookup_revalidate(inode);
inode->i_version = fattr->change_attr;
}
} else if (server->caps & NFS_CAP_CHANGE_ATTR)
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;
invalid &= ~NFS_INO_REVAL_PAGECACHE;
}
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;
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;
}
}
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 = (struct nfs_inode *)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;
#ifdef CONFIG_PROC_FS
rpc_proc_register(&init_net, &nfs_rpcstat);
#endif
if ((err = register_nfs_fs()) != 0)
goto out0;
return 0;
out0:
#ifdef CONFIG_PROC_FS
rpc_proc_unregister(&init_net, "nfs");
#endif
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);
#ifdef CONFIG_PROC_FS
rpc_proc_unregister(&init_net, "nfs");
#endif
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)
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