706 lines
18 KiB
C
706 lines
18 KiB
C
/*
|
|
* linux/fs/nfs/delegation.c
|
|
*
|
|
* Copyright (C) 2004 Trond Myklebust
|
|
*
|
|
* NFS file delegation management
|
|
*
|
|
*/
|
|
#include <linux/completion.h>
|
|
#include <linux/kthread.h>
|
|
#include <linux/module.h>
|
|
#include <linux/sched.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/spinlock.h>
|
|
|
|
#include <linux/nfs4.h>
|
|
#include <linux/nfs_fs.h>
|
|
#include <linux/nfs_xdr.h>
|
|
|
|
#include "nfs4_fs.h"
|
|
#include "delegation.h"
|
|
#include "internal.h"
|
|
|
|
static void nfs_free_delegation(struct nfs_delegation *delegation)
|
|
{
|
|
if (delegation->cred) {
|
|
put_rpccred(delegation->cred);
|
|
delegation->cred = NULL;
|
|
}
|
|
kfree_rcu(delegation, rcu);
|
|
}
|
|
|
|
/**
|
|
* nfs_mark_delegation_referenced - set delegation's REFERENCED flag
|
|
* @delegation: delegation to process
|
|
*
|
|
*/
|
|
void nfs_mark_delegation_referenced(struct nfs_delegation *delegation)
|
|
{
|
|
set_bit(NFS_DELEGATION_REFERENCED, &delegation->flags);
|
|
}
|
|
|
|
/**
|
|
* nfs_have_delegation - check if inode has a delegation
|
|
* @inode: inode to check
|
|
* @flags: delegation types to check for
|
|
*
|
|
* Returns one if inode has the indicated delegation, otherwise zero.
|
|
*/
|
|
int nfs_have_delegation(struct inode *inode, fmode_t flags)
|
|
{
|
|
struct nfs_delegation *delegation;
|
|
int ret = 0;
|
|
|
|
flags &= FMODE_READ|FMODE_WRITE;
|
|
rcu_read_lock();
|
|
delegation = rcu_dereference(NFS_I(inode)->delegation);
|
|
if (delegation != NULL && (delegation->type & flags) == flags) {
|
|
nfs_mark_delegation_referenced(delegation);
|
|
ret = 1;
|
|
}
|
|
rcu_read_unlock();
|
|
return ret;
|
|
}
|
|
|
|
static int nfs_delegation_claim_locks(struct nfs_open_context *ctx, struct nfs4_state *state)
|
|
{
|
|
struct inode *inode = state->inode;
|
|
struct file_lock *fl;
|
|
int status = 0;
|
|
|
|
if (inode->i_flock == NULL)
|
|
goto out;
|
|
|
|
/* Protect inode->i_flock using the file locks lock */
|
|
lock_flocks();
|
|
for (fl = inode->i_flock; fl != NULL; fl = fl->fl_next) {
|
|
if (!(fl->fl_flags & (FL_POSIX|FL_FLOCK)))
|
|
continue;
|
|
if (nfs_file_open_context(fl->fl_file) != ctx)
|
|
continue;
|
|
unlock_flocks();
|
|
status = nfs4_lock_delegation_recall(state, fl);
|
|
if (status < 0)
|
|
goto out;
|
|
lock_flocks();
|
|
}
|
|
unlock_flocks();
|
|
out:
|
|
return status;
|
|
}
|
|
|
|
static int nfs_delegation_claim_opens(struct inode *inode, const nfs4_stateid *stateid)
|
|
{
|
|
struct nfs_inode *nfsi = NFS_I(inode);
|
|
struct nfs_open_context *ctx;
|
|
struct nfs4_state *state;
|
|
int err;
|
|
|
|
again:
|
|
spin_lock(&inode->i_lock);
|
|
list_for_each_entry(ctx, &nfsi->open_files, list) {
|
|
state = ctx->state;
|
|
if (state == NULL)
|
|
continue;
|
|
if (!test_bit(NFS_DELEGATED_STATE, &state->flags))
|
|
continue;
|
|
if (!nfs4_stateid_match(&state->stateid, stateid))
|
|
continue;
|
|
get_nfs_open_context(ctx);
|
|
spin_unlock(&inode->i_lock);
|
|
err = nfs4_open_delegation_recall(ctx, state, stateid);
|
|
if (err >= 0)
|
|
err = nfs_delegation_claim_locks(ctx, state);
|
|
put_nfs_open_context(ctx);
|
|
if (err != 0)
|
|
return err;
|
|
goto again;
|
|
}
|
|
spin_unlock(&inode->i_lock);
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* nfs_inode_reclaim_delegation - process a delegation reclaim request
|
|
* @inode: inode to process
|
|
* @cred: credential to use for request
|
|
* @res: new delegation state from server
|
|
*
|
|
*/
|
|
void nfs_inode_reclaim_delegation(struct inode *inode, struct rpc_cred *cred,
|
|
struct nfs_openres *res)
|
|
{
|
|
struct nfs_delegation *delegation;
|
|
struct rpc_cred *oldcred = NULL;
|
|
|
|
rcu_read_lock();
|
|
delegation = rcu_dereference(NFS_I(inode)->delegation);
|
|
if (delegation != NULL) {
|
|
spin_lock(&delegation->lock);
|
|
if (delegation->inode != NULL) {
|
|
nfs4_stateid_copy(&delegation->stateid, &res->delegation);
|
|
delegation->type = res->delegation_type;
|
|
delegation->maxsize = res->maxsize;
|
|
oldcred = delegation->cred;
|
|
delegation->cred = get_rpccred(cred);
|
|
clear_bit(NFS_DELEGATION_NEED_RECLAIM,
|
|
&delegation->flags);
|
|
NFS_I(inode)->delegation_state = delegation->type;
|
|
spin_unlock(&delegation->lock);
|
|
put_rpccred(oldcred);
|
|
rcu_read_unlock();
|
|
} else {
|
|
/* We appear to have raced with a delegation return. */
|
|
spin_unlock(&delegation->lock);
|
|
rcu_read_unlock();
|
|
nfs_inode_set_delegation(inode, cred, res);
|
|
}
|
|
} else {
|
|
rcu_read_unlock();
|
|
}
|
|
}
|
|
|
|
static int nfs_do_return_delegation(struct inode *inode, struct nfs_delegation *delegation, int issync)
|
|
{
|
|
int res = 0;
|
|
|
|
res = nfs4_proc_delegreturn(inode, delegation->cred, &delegation->stateid, issync);
|
|
nfs_free_delegation(delegation);
|
|
return res;
|
|
}
|
|
|
|
static struct inode *nfs_delegation_grab_inode(struct nfs_delegation *delegation)
|
|
{
|
|
struct inode *inode = NULL;
|
|
|
|
spin_lock(&delegation->lock);
|
|
if (delegation->inode != NULL)
|
|
inode = igrab(delegation->inode);
|
|
spin_unlock(&delegation->lock);
|
|
return inode;
|
|
}
|
|
|
|
static struct nfs_delegation *
|
|
nfs_detach_delegation_locked(struct nfs_inode *nfsi,
|
|
struct nfs_server *server)
|
|
{
|
|
struct nfs_delegation *delegation =
|
|
rcu_dereference_protected(nfsi->delegation,
|
|
lockdep_is_held(&server->nfs_client->cl_lock));
|
|
|
|
if (delegation == NULL)
|
|
goto nomatch;
|
|
|
|
spin_lock(&delegation->lock);
|
|
list_del_rcu(&delegation->super_list);
|
|
delegation->inode = NULL;
|
|
nfsi->delegation_state = 0;
|
|
rcu_assign_pointer(nfsi->delegation, NULL);
|
|
spin_unlock(&delegation->lock);
|
|
return delegation;
|
|
nomatch:
|
|
return NULL;
|
|
}
|
|
|
|
static struct nfs_delegation *nfs_detach_delegation(struct nfs_inode *nfsi,
|
|
struct nfs_server *server)
|
|
{
|
|
struct nfs_client *clp = server->nfs_client;
|
|
struct nfs_delegation *delegation;
|
|
|
|
spin_lock(&clp->cl_lock);
|
|
delegation = nfs_detach_delegation_locked(nfsi, server);
|
|
spin_unlock(&clp->cl_lock);
|
|
return delegation;
|
|
}
|
|
|
|
/**
|
|
* nfs_inode_set_delegation - set up a delegation on an inode
|
|
* @inode: inode to which delegation applies
|
|
* @cred: cred to use for subsequent delegation processing
|
|
* @res: new delegation state from server
|
|
*
|
|
* Returns zero on success, or a negative errno value.
|
|
*/
|
|
int nfs_inode_set_delegation(struct inode *inode, struct rpc_cred *cred, struct nfs_openres *res)
|
|
{
|
|
struct nfs_server *server = NFS_SERVER(inode);
|
|
struct nfs_client *clp = server->nfs_client;
|
|
struct nfs_inode *nfsi = NFS_I(inode);
|
|
struct nfs_delegation *delegation, *old_delegation;
|
|
struct nfs_delegation *freeme = NULL;
|
|
int status = 0;
|
|
|
|
delegation = kmalloc(sizeof(*delegation), GFP_NOFS);
|
|
if (delegation == NULL)
|
|
return -ENOMEM;
|
|
nfs4_stateid_copy(&delegation->stateid, &res->delegation);
|
|
delegation->type = res->delegation_type;
|
|
delegation->maxsize = res->maxsize;
|
|
delegation->change_attr = inode->i_version;
|
|
delegation->cred = get_rpccred(cred);
|
|
delegation->inode = inode;
|
|
delegation->flags = 1<<NFS_DELEGATION_REFERENCED;
|
|
spin_lock_init(&delegation->lock);
|
|
|
|
spin_lock(&clp->cl_lock);
|
|
old_delegation = rcu_dereference_protected(nfsi->delegation,
|
|
lockdep_is_held(&clp->cl_lock));
|
|
if (old_delegation != NULL) {
|
|
if (nfs4_stateid_match(&delegation->stateid,
|
|
&old_delegation->stateid) &&
|
|
delegation->type == old_delegation->type) {
|
|
goto out;
|
|
}
|
|
/*
|
|
* Deal with broken servers that hand out two
|
|
* delegations for the same file.
|
|
* Allow for upgrades to a WRITE delegation, but
|
|
* nothing else.
|
|
*/
|
|
dfprintk(FILE, "%s: server %s handed out "
|
|
"a duplicate delegation!\n",
|
|
__func__, clp->cl_hostname);
|
|
if (delegation->type == old_delegation->type ||
|
|
!(delegation->type & FMODE_WRITE)) {
|
|
freeme = delegation;
|
|
delegation = NULL;
|
|
goto out;
|
|
}
|
|
freeme = nfs_detach_delegation_locked(nfsi, server);
|
|
}
|
|
list_add_rcu(&delegation->super_list, &server->delegations);
|
|
nfsi->delegation_state = delegation->type;
|
|
rcu_assign_pointer(nfsi->delegation, delegation);
|
|
delegation = NULL;
|
|
|
|
/* Ensure we revalidate the attributes and page cache! */
|
|
spin_lock(&inode->i_lock);
|
|
nfsi->cache_validity |= NFS_INO_REVAL_FORCED;
|
|
spin_unlock(&inode->i_lock);
|
|
|
|
out:
|
|
spin_unlock(&clp->cl_lock);
|
|
if (delegation != NULL)
|
|
nfs_free_delegation(delegation);
|
|
if (freeme != NULL)
|
|
nfs_do_return_delegation(inode, freeme, 0);
|
|
return status;
|
|
}
|
|
|
|
/*
|
|
* Basic procedure for returning a delegation to the server
|
|
*/
|
|
static int __nfs_inode_return_delegation(struct inode *inode, struct nfs_delegation *delegation, int issync)
|
|
{
|
|
struct nfs_inode *nfsi = NFS_I(inode);
|
|
int err;
|
|
|
|
/*
|
|
* Guard against new delegated open/lock/unlock calls and against
|
|
* state recovery
|
|
*/
|
|
down_write(&nfsi->rwsem);
|
|
err = nfs_delegation_claim_opens(inode, &delegation->stateid);
|
|
up_write(&nfsi->rwsem);
|
|
if (err)
|
|
goto out;
|
|
|
|
err = nfs_do_return_delegation(inode, delegation, issync);
|
|
out:
|
|
return err;
|
|
}
|
|
|
|
/**
|
|
* nfs_client_return_marked_delegations - return previously marked delegations
|
|
* @clp: nfs_client to process
|
|
*
|
|
* Returns zero on success, or a negative errno value.
|
|
*/
|
|
int nfs_client_return_marked_delegations(struct nfs_client *clp)
|
|
{
|
|
struct nfs_delegation *delegation;
|
|
struct nfs_server *server;
|
|
struct inode *inode;
|
|
int err = 0;
|
|
|
|
restart:
|
|
rcu_read_lock();
|
|
list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
|
|
list_for_each_entry_rcu(delegation, &server->delegations,
|
|
super_list) {
|
|
if (!test_and_clear_bit(NFS_DELEGATION_RETURN,
|
|
&delegation->flags))
|
|
continue;
|
|
inode = nfs_delegation_grab_inode(delegation);
|
|
if (inode == NULL)
|
|
continue;
|
|
delegation = nfs_detach_delegation(NFS_I(inode),
|
|
server);
|
|
rcu_read_unlock();
|
|
|
|
if (delegation != NULL) {
|
|
filemap_flush(inode->i_mapping);
|
|
err = __nfs_inode_return_delegation(inode,
|
|
delegation, 0);
|
|
}
|
|
iput(inode);
|
|
if (!err)
|
|
goto restart;
|
|
set_bit(NFS4CLNT_DELEGRETURN, &clp->cl_state);
|
|
return err;
|
|
}
|
|
}
|
|
rcu_read_unlock();
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* nfs_inode_return_delegation_noreclaim - return delegation, don't reclaim opens
|
|
* @inode: inode to process
|
|
*
|
|
* Does not protect against delegation reclaims, therefore really only safe
|
|
* to be called from nfs4_clear_inode().
|
|
*/
|
|
void nfs_inode_return_delegation_noreclaim(struct inode *inode)
|
|
{
|
|
struct nfs_server *server = NFS_SERVER(inode);
|
|
struct nfs_inode *nfsi = NFS_I(inode);
|
|
struct nfs_delegation *delegation;
|
|
|
|
if (rcu_access_pointer(nfsi->delegation) != NULL) {
|
|
delegation = nfs_detach_delegation(nfsi, server);
|
|
if (delegation != NULL)
|
|
nfs_do_return_delegation(inode, delegation, 0);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* nfs_inode_return_delegation - synchronously return a delegation
|
|
* @inode: inode to process
|
|
*
|
|
* Returns zero on success, or a negative errno value.
|
|
*/
|
|
int nfs_inode_return_delegation(struct inode *inode)
|
|
{
|
|
struct nfs_server *server = NFS_SERVER(inode);
|
|
struct nfs_inode *nfsi = NFS_I(inode);
|
|
struct nfs_delegation *delegation;
|
|
int err = 0;
|
|
|
|
if (rcu_access_pointer(nfsi->delegation) != NULL) {
|
|
delegation = nfs_detach_delegation(nfsi, server);
|
|
if (delegation != NULL) {
|
|
nfs_wb_all(inode);
|
|
err = __nfs_inode_return_delegation(inode, delegation, 1);
|
|
}
|
|
}
|
|
return err;
|
|
}
|
|
|
|
static void nfs_mark_return_delegation(struct nfs_server *server,
|
|
struct nfs_delegation *delegation)
|
|
{
|
|
set_bit(NFS_DELEGATION_RETURN, &delegation->flags);
|
|
set_bit(NFS4CLNT_DELEGRETURN, &server->nfs_client->cl_state);
|
|
}
|
|
|
|
/**
|
|
* nfs_super_return_all_delegations - return delegations for one superblock
|
|
* @sb: sb to process
|
|
*
|
|
*/
|
|
void nfs_super_return_all_delegations(struct super_block *sb)
|
|
{
|
|
struct nfs_server *server = NFS_SB(sb);
|
|
struct nfs_client *clp = server->nfs_client;
|
|
struct nfs_delegation *delegation;
|
|
|
|
if (clp == NULL)
|
|
return;
|
|
|
|
rcu_read_lock();
|
|
list_for_each_entry_rcu(delegation, &server->delegations, super_list) {
|
|
spin_lock(&delegation->lock);
|
|
set_bit(NFS_DELEGATION_RETURN, &delegation->flags);
|
|
spin_unlock(&delegation->lock);
|
|
}
|
|
rcu_read_unlock();
|
|
|
|
if (nfs_client_return_marked_delegations(clp) != 0)
|
|
nfs4_schedule_state_manager(clp);
|
|
}
|
|
|
|
static void nfs_mark_return_all_delegation_types(struct nfs_server *server,
|
|
fmode_t flags)
|
|
{
|
|
struct nfs_delegation *delegation;
|
|
|
|
list_for_each_entry_rcu(delegation, &server->delegations, super_list) {
|
|
if ((delegation->type == (FMODE_READ|FMODE_WRITE)) && !(flags & FMODE_WRITE))
|
|
continue;
|
|
if (delegation->type & flags)
|
|
nfs_mark_return_delegation(server, delegation);
|
|
}
|
|
}
|
|
|
|
static void nfs_client_mark_return_all_delegation_types(struct nfs_client *clp,
|
|
fmode_t flags)
|
|
{
|
|
struct nfs_server *server;
|
|
|
|
rcu_read_lock();
|
|
list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
|
|
nfs_mark_return_all_delegation_types(server, flags);
|
|
rcu_read_unlock();
|
|
}
|
|
|
|
static void nfs_delegation_run_state_manager(struct nfs_client *clp)
|
|
{
|
|
if (test_bit(NFS4CLNT_DELEGRETURN, &clp->cl_state))
|
|
nfs4_schedule_state_manager(clp);
|
|
}
|
|
|
|
void nfs_remove_bad_delegation(struct inode *inode)
|
|
{
|
|
struct nfs_delegation *delegation;
|
|
|
|
delegation = nfs_detach_delegation(NFS_I(inode), NFS_SERVER(inode));
|
|
if (delegation) {
|
|
nfs_inode_find_state_and_recover(inode, &delegation->stateid);
|
|
nfs_free_delegation(delegation);
|
|
}
|
|
}
|
|
EXPORT_SYMBOL_GPL(nfs_remove_bad_delegation);
|
|
|
|
/**
|
|
* nfs_expire_all_delegation_types
|
|
* @clp: client to process
|
|
* @flags: delegation types to expire
|
|
*
|
|
*/
|
|
void nfs_expire_all_delegation_types(struct nfs_client *clp, fmode_t flags)
|
|
{
|
|
nfs_client_mark_return_all_delegation_types(clp, flags);
|
|
nfs_delegation_run_state_manager(clp);
|
|
}
|
|
|
|
/**
|
|
* nfs_expire_all_delegations
|
|
* @clp: client to process
|
|
*
|
|
*/
|
|
void nfs_expire_all_delegations(struct nfs_client *clp)
|
|
{
|
|
nfs_expire_all_delegation_types(clp, FMODE_READ|FMODE_WRITE);
|
|
}
|
|
|
|
static void nfs_mark_return_unreferenced_delegations(struct nfs_server *server)
|
|
{
|
|
struct nfs_delegation *delegation;
|
|
|
|
list_for_each_entry_rcu(delegation, &server->delegations, super_list) {
|
|
if (test_and_clear_bit(NFS_DELEGATION_REFERENCED, &delegation->flags))
|
|
continue;
|
|
nfs_mark_return_delegation(server, delegation);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* nfs_expire_unreferenced_delegations - Eliminate unused delegations
|
|
* @clp: nfs_client to process
|
|
*
|
|
*/
|
|
void nfs_expire_unreferenced_delegations(struct nfs_client *clp)
|
|
{
|
|
struct nfs_server *server;
|
|
|
|
rcu_read_lock();
|
|
list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
|
|
nfs_mark_return_unreferenced_delegations(server);
|
|
rcu_read_unlock();
|
|
|
|
nfs_delegation_run_state_manager(clp);
|
|
}
|
|
|
|
/**
|
|
* nfs_async_inode_return_delegation - asynchronously return a delegation
|
|
* @inode: inode to process
|
|
* @stateid: state ID information
|
|
*
|
|
* Returns zero on success, or a negative errno value.
|
|
*/
|
|
int nfs_async_inode_return_delegation(struct inode *inode,
|
|
const nfs4_stateid *stateid)
|
|
{
|
|
struct nfs_server *server = NFS_SERVER(inode);
|
|
struct nfs_client *clp = server->nfs_client;
|
|
struct nfs_delegation *delegation;
|
|
|
|
rcu_read_lock();
|
|
delegation = rcu_dereference(NFS_I(inode)->delegation);
|
|
|
|
if (!clp->cl_mvops->match_stateid(&delegation->stateid, stateid)) {
|
|
rcu_read_unlock();
|
|
return -ENOENT;
|
|
}
|
|
nfs_mark_return_delegation(server, delegation);
|
|
rcu_read_unlock();
|
|
|
|
nfs_delegation_run_state_manager(clp);
|
|
return 0;
|
|
}
|
|
|
|
static struct inode *
|
|
nfs_delegation_find_inode_server(struct nfs_server *server,
|
|
const struct nfs_fh *fhandle)
|
|
{
|
|
struct nfs_delegation *delegation;
|
|
struct inode *res = NULL;
|
|
|
|
list_for_each_entry_rcu(delegation, &server->delegations, super_list) {
|
|
spin_lock(&delegation->lock);
|
|
if (delegation->inode != NULL &&
|
|
nfs_compare_fh(fhandle, &NFS_I(delegation->inode)->fh) == 0) {
|
|
res = igrab(delegation->inode);
|
|
}
|
|
spin_unlock(&delegation->lock);
|
|
if (res != NULL)
|
|
break;
|
|
}
|
|
return res;
|
|
}
|
|
|
|
/**
|
|
* nfs_delegation_find_inode - retrieve the inode associated with a delegation
|
|
* @clp: client state handle
|
|
* @fhandle: filehandle from a delegation recall
|
|
*
|
|
* Returns pointer to inode matching "fhandle," or NULL if a matching inode
|
|
* cannot be found.
|
|
*/
|
|
struct inode *nfs_delegation_find_inode(struct nfs_client *clp,
|
|
const struct nfs_fh *fhandle)
|
|
{
|
|
struct nfs_server *server;
|
|
struct inode *res = NULL;
|
|
|
|
rcu_read_lock();
|
|
list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
|
|
res = nfs_delegation_find_inode_server(server, fhandle);
|
|
if (res != NULL)
|
|
break;
|
|
}
|
|
rcu_read_unlock();
|
|
return res;
|
|
}
|
|
|
|
static void nfs_delegation_mark_reclaim_server(struct nfs_server *server)
|
|
{
|
|
struct nfs_delegation *delegation;
|
|
|
|
list_for_each_entry_rcu(delegation, &server->delegations, super_list)
|
|
set_bit(NFS_DELEGATION_NEED_RECLAIM, &delegation->flags);
|
|
}
|
|
|
|
/**
|
|
* nfs_delegation_mark_reclaim - mark all delegations as needing to be reclaimed
|
|
* @clp: nfs_client to process
|
|
*
|
|
*/
|
|
void nfs_delegation_mark_reclaim(struct nfs_client *clp)
|
|
{
|
|
struct nfs_server *server;
|
|
|
|
rcu_read_lock();
|
|
list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
|
|
nfs_delegation_mark_reclaim_server(server);
|
|
rcu_read_unlock();
|
|
}
|
|
|
|
/**
|
|
* nfs_delegation_reap_unclaimed - reap unclaimed delegations after reboot recovery is done
|
|
* @clp: nfs_client to process
|
|
*
|
|
*/
|
|
void nfs_delegation_reap_unclaimed(struct nfs_client *clp)
|
|
{
|
|
struct nfs_delegation *delegation;
|
|
struct nfs_server *server;
|
|
struct inode *inode;
|
|
|
|
restart:
|
|
rcu_read_lock();
|
|
list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
|
|
list_for_each_entry_rcu(delegation, &server->delegations,
|
|
super_list) {
|
|
if (test_bit(NFS_DELEGATION_NEED_RECLAIM,
|
|
&delegation->flags) == 0)
|
|
continue;
|
|
inode = nfs_delegation_grab_inode(delegation);
|
|
if (inode == NULL)
|
|
continue;
|
|
delegation = nfs_detach_delegation(NFS_I(inode),
|
|
server);
|
|
rcu_read_unlock();
|
|
|
|
if (delegation != NULL)
|
|
nfs_free_delegation(delegation);
|
|
iput(inode);
|
|
goto restart;
|
|
}
|
|
}
|
|
rcu_read_unlock();
|
|
}
|
|
|
|
/**
|
|
* nfs_delegations_present - check for existence of delegations
|
|
* @clp: client state handle
|
|
*
|
|
* Returns one if there are any nfs_delegation structures attached
|
|
* to this nfs_client.
|
|
*/
|
|
int nfs_delegations_present(struct nfs_client *clp)
|
|
{
|
|
struct nfs_server *server;
|
|
int ret = 0;
|
|
|
|
rcu_read_lock();
|
|
list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
|
|
if (!list_empty(&server->delegations)) {
|
|
ret = 1;
|
|
break;
|
|
}
|
|
rcu_read_unlock();
|
|
return ret;
|
|
}
|
|
|
|
/**
|
|
* nfs4_copy_delegation_stateid - Copy inode's state ID information
|
|
* @dst: stateid data structure to fill in
|
|
* @inode: inode to check
|
|
* @flags: delegation type requirement
|
|
*
|
|
* Returns "true" and fills in "dst->data" * if inode had a delegation,
|
|
* otherwise "false" is returned.
|
|
*/
|
|
bool nfs4_copy_delegation_stateid(nfs4_stateid *dst, struct inode *inode,
|
|
fmode_t flags)
|
|
{
|
|
struct nfs_inode *nfsi = NFS_I(inode);
|
|
struct nfs_delegation *delegation;
|
|
bool ret;
|
|
|
|
flags &= FMODE_READ|FMODE_WRITE;
|
|
rcu_read_lock();
|
|
delegation = rcu_dereference(nfsi->delegation);
|
|
ret = (delegation != NULL && (delegation->type & flags) == flags);
|
|
if (ret) {
|
|
nfs4_stateid_copy(dst, &delegation->stateid);
|
|
nfs_mark_delegation_referenced(delegation);
|
|
}
|
|
rcu_read_unlock();
|
|
return ret;
|
|
}
|