523 lines
14 KiB
C
523 lines
14 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/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_do_free_delegation(struct nfs_delegation *delegation)
|
|
{
|
|
kfree(delegation);
|
|
}
|
|
|
|
static void nfs_free_delegation_callback(struct rcu_head *head)
|
|
{
|
|
struct nfs_delegation *delegation = container_of(head, struct nfs_delegation, rcu);
|
|
|
|
nfs_do_free_delegation(delegation);
|
|
}
|
|
|
|
static void nfs_free_delegation(struct nfs_delegation *delegation)
|
|
{
|
|
struct rpc_cred *cred;
|
|
|
|
cred = rcu_dereference(delegation->cred);
|
|
rcu_assign_pointer(delegation->cred, NULL);
|
|
call_rcu(&delegation->rcu, nfs_free_delegation_callback);
|
|
if (cred)
|
|
put_rpccred(cred);
|
|
}
|
|
|
|
void nfs_mark_delegation_referenced(struct nfs_delegation *delegation)
|
|
{
|
|
set_bit(NFS_DELEGATION_REFERENCED, &delegation->flags);
|
|
}
|
|
|
|
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;
|
|
|
|
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;
|
|
status = nfs4_lock_delegation_recall(state, fl);
|
|
if (status >= 0)
|
|
continue;
|
|
switch (status) {
|
|
default:
|
|
printk(KERN_ERR "%s: unhandled error %d.\n",
|
|
__func__, status);
|
|
case -NFS4ERR_EXPIRED:
|
|
/* kill_proc(fl->fl_pid, SIGLOST, 1); */
|
|
case -NFS4ERR_STALE_CLIENTID:
|
|
nfs4_schedule_state_recovery(NFS_SERVER(inode)->nfs_client);
|
|
goto out_err;
|
|
}
|
|
}
|
|
return 0;
|
|
out_err:
|
|
return status;
|
|
}
|
|
|
|
static void 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 (memcmp(state->stateid.data, stateid->data, sizeof(state->stateid.data)) != 0)
|
|
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;
|
|
goto again;
|
|
}
|
|
spin_unlock(&inode->i_lock);
|
|
}
|
|
|
|
/*
|
|
* Set up a delegation on an inode
|
|
*/
|
|
void nfs_inode_reclaim_delegation(struct inode *inode, struct rpc_cred *cred, struct nfs_openres *res)
|
|
{
|
|
struct nfs_delegation *delegation = NFS_I(inode)->delegation;
|
|
struct rpc_cred *oldcred;
|
|
|
|
if (delegation == NULL)
|
|
return;
|
|
memcpy(delegation->stateid.data, res->delegation.data,
|
|
sizeof(delegation->stateid.data));
|
|
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;
|
|
smp_wmb();
|
|
put_rpccred(oldcred);
|
|
}
|
|
|
|
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, const nfs4_stateid *stateid)
|
|
{
|
|
struct nfs_delegation *delegation = rcu_dereference(nfsi->delegation);
|
|
|
|
if (delegation == NULL)
|
|
goto nomatch;
|
|
spin_lock(&delegation->lock);
|
|
if (stateid != NULL && memcmp(delegation->stateid.data, stateid->data,
|
|
sizeof(delegation->stateid.data)) != 0)
|
|
goto nomatch_unlock;
|
|
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_unlock:
|
|
spin_unlock(&delegation->lock);
|
|
nomatch:
|
|
return NULL;
|
|
}
|
|
|
|
/*
|
|
* Set up a delegation on an inode
|
|
*/
|
|
int nfs_inode_set_delegation(struct inode *inode, struct rpc_cred *cred, struct nfs_openres *res)
|
|
{
|
|
struct nfs_client *clp = NFS_SERVER(inode)->nfs_client;
|
|
struct nfs_inode *nfsi = NFS_I(inode);
|
|
struct nfs_delegation *delegation;
|
|
struct nfs_delegation *freeme = NULL;
|
|
int status = 0;
|
|
|
|
delegation = kmalloc(sizeof(*delegation), GFP_KERNEL);
|
|
if (delegation == NULL)
|
|
return -ENOMEM;
|
|
memcpy(delegation->stateid.data, res->delegation.data,
|
|
sizeof(delegation->stateid.data));
|
|
delegation->type = res->delegation_type;
|
|
delegation->maxsize = res->maxsize;
|
|
delegation->change_attr = nfsi->change_attr;
|
|
delegation->cred = get_rpccred(cred);
|
|
delegation->inode = inode;
|
|
delegation->flags = 1<<NFS_DELEGATION_REFERENCED;
|
|
spin_lock_init(&delegation->lock);
|
|
|
|
spin_lock(&clp->cl_lock);
|
|
if (rcu_dereference(nfsi->delegation) != NULL) {
|
|
if (memcmp(&delegation->stateid, &nfsi->delegation->stateid,
|
|
sizeof(delegation->stateid)) == 0 &&
|
|
delegation->type == nfsi->delegation->type) {
|
|
goto out;
|
|
}
|
|
/*
|
|
* Deal with broken servers that hand out two
|
|
* delegations for the same file.
|
|
*/
|
|
dfprintk(FILE, "%s: server %s handed out "
|
|
"a duplicate delegation!\n",
|
|
__func__, clp->cl_hostname);
|
|
if (delegation->type <= nfsi->delegation->type) {
|
|
freeme = delegation;
|
|
delegation = NULL;
|
|
goto out;
|
|
}
|
|
freeme = nfs_detach_delegation_locked(nfsi, NULL);
|
|
}
|
|
list_add_rcu(&delegation->super_list, &clp->cl_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;
|
|
}
|
|
|
|
/* Sync all data to disk upon delegation return */
|
|
static void nfs_msync_inode(struct inode *inode)
|
|
{
|
|
filemap_fdatawrite(inode->i_mapping);
|
|
nfs_wb_all(inode);
|
|
filemap_fdatawait(inode->i_mapping);
|
|
}
|
|
|
|
/*
|
|
* Basic procedure for returning a delegation to the server
|
|
*/
|
|
static int __nfs_inode_return_delegation(struct inode *inode, struct nfs_delegation *delegation)
|
|
{
|
|
struct nfs_inode *nfsi = NFS_I(inode);
|
|
|
|
nfs_msync_inode(inode);
|
|
/* Guard against new delegated open calls */
|
|
down_write(&nfsi->rwsem);
|
|
nfs_delegation_claim_opens(inode, &delegation->stateid);
|
|
up_write(&nfsi->rwsem);
|
|
nfs_msync_inode(inode);
|
|
|
|
return nfs_do_return_delegation(inode, delegation, 1);
|
|
}
|
|
|
|
/*
|
|
* Return all delegations that have been marked for return
|
|
*/
|
|
void nfs_client_return_marked_delegations(struct nfs_client *clp)
|
|
{
|
|
struct nfs_delegation *delegation;
|
|
struct inode *inode;
|
|
|
|
restart:
|
|
rcu_read_lock();
|
|
list_for_each_entry_rcu(delegation, &clp->cl_delegations, super_list) {
|
|
if (!test_and_clear_bit(NFS_DELEGATION_RETURN, &delegation->flags))
|
|
continue;
|
|
inode = nfs_delegation_grab_inode(delegation);
|
|
if (inode == NULL)
|
|
continue;
|
|
spin_lock(&clp->cl_lock);
|
|
delegation = nfs_detach_delegation_locked(NFS_I(inode), NULL);
|
|
spin_unlock(&clp->cl_lock);
|
|
rcu_read_unlock();
|
|
if (delegation != NULL)
|
|
__nfs_inode_return_delegation(inode, delegation);
|
|
iput(inode);
|
|
goto restart;
|
|
}
|
|
rcu_read_unlock();
|
|
}
|
|
|
|
/*
|
|
* This function returns the delegation without reclaiming opens
|
|
* or protecting against delegation reclaims.
|
|
* It is therefore really only safe to be called from
|
|
* nfs4_clear_inode()
|
|
*/
|
|
void nfs_inode_return_delegation_noreclaim(struct inode *inode)
|
|
{
|
|
struct nfs_client *clp = NFS_SERVER(inode)->nfs_client;
|
|
struct nfs_inode *nfsi = NFS_I(inode);
|
|
struct nfs_delegation *delegation;
|
|
|
|
if (rcu_dereference(nfsi->delegation) != NULL) {
|
|
spin_lock(&clp->cl_lock);
|
|
delegation = nfs_detach_delegation_locked(nfsi, NULL);
|
|
spin_unlock(&clp->cl_lock);
|
|
if (delegation != NULL)
|
|
nfs_do_return_delegation(inode, delegation, 0);
|
|
}
|
|
}
|
|
|
|
int nfs_inode_return_delegation(struct inode *inode)
|
|
{
|
|
struct nfs_client *clp = NFS_SERVER(inode)->nfs_client;
|
|
struct nfs_inode *nfsi = NFS_I(inode);
|
|
struct nfs_delegation *delegation;
|
|
int err = 0;
|
|
|
|
if (rcu_dereference(nfsi->delegation) != NULL) {
|
|
spin_lock(&clp->cl_lock);
|
|
delegation = nfs_detach_delegation_locked(nfsi, NULL);
|
|
spin_unlock(&clp->cl_lock);
|
|
if (delegation != NULL)
|
|
err = __nfs_inode_return_delegation(inode, delegation);
|
|
}
|
|
return err;
|
|
}
|
|
|
|
static void nfs_mark_return_delegation(struct nfs_client *clp, struct nfs_delegation *delegation)
|
|
{
|
|
set_bit(NFS_DELEGATION_RETURN, &delegation->flags);
|
|
set_bit(NFS4CLNT_DELEGRETURN, &clp->cl_state);
|
|
}
|
|
|
|
/*
|
|
* Return all delegations associated to a super block
|
|
*/
|
|
void nfs_super_return_all_delegations(struct super_block *sb)
|
|
{
|
|
struct nfs_client *clp = NFS_SB(sb)->nfs_client;
|
|
struct nfs_delegation *delegation;
|
|
|
|
if (clp == NULL)
|
|
return;
|
|
rcu_read_lock();
|
|
list_for_each_entry_rcu(delegation, &clp->cl_delegations, super_list) {
|
|
spin_lock(&delegation->lock);
|
|
if (delegation->inode != NULL && delegation->inode->i_sb == sb)
|
|
set_bit(NFS_DELEGATION_RETURN, &delegation->flags);
|
|
spin_unlock(&delegation->lock);
|
|
}
|
|
rcu_read_unlock();
|
|
nfs_client_return_marked_delegations(clp);
|
|
}
|
|
|
|
static void nfs_client_mark_return_all_delegations(struct nfs_client *clp)
|
|
{
|
|
struct nfs_delegation *delegation;
|
|
|
|
rcu_read_lock();
|
|
list_for_each_entry_rcu(delegation, &clp->cl_delegations, super_list) {
|
|
set_bit(NFS_DELEGATION_RETURN, &delegation->flags);
|
|
set_bit(NFS4CLNT_DELEGRETURN, &clp->cl_state);
|
|
}
|
|
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_expire_all_delegations(struct nfs_client *clp)
|
|
{
|
|
nfs_client_mark_return_all_delegations(clp);
|
|
nfs_delegation_run_state_manager(clp);
|
|
}
|
|
|
|
/*
|
|
* Return all delegations following an NFS4ERR_CB_PATH_DOWN error.
|
|
*/
|
|
void nfs_handle_cb_pathdown(struct nfs_client *clp)
|
|
{
|
|
if (clp == NULL)
|
|
return;
|
|
nfs_client_mark_return_all_delegations(clp);
|
|
}
|
|
|
|
static void nfs_client_mark_return_unreferenced_delegations(struct nfs_client *clp)
|
|
{
|
|
struct nfs_delegation *delegation;
|
|
|
|
rcu_read_lock();
|
|
list_for_each_entry_rcu(delegation, &clp->cl_delegations, super_list) {
|
|
if (test_and_clear_bit(NFS_DELEGATION_REFERENCED, &delegation->flags))
|
|
continue;
|
|
set_bit(NFS_DELEGATION_RETURN, &delegation->flags);
|
|
set_bit(NFS4CLNT_DELEGRETURN, &clp->cl_state);
|
|
}
|
|
rcu_read_unlock();
|
|
}
|
|
|
|
void nfs_expire_unreferenced_delegations(struct nfs_client *clp)
|
|
{
|
|
nfs_client_mark_return_unreferenced_delegations(clp);
|
|
nfs_delegation_run_state_manager(clp);
|
|
}
|
|
|
|
/*
|
|
* Asynchronous delegation recall!
|
|
*/
|
|
int nfs_async_inode_return_delegation(struct inode *inode, const nfs4_stateid *stateid)
|
|
{
|
|
struct nfs_client *clp = NFS_SERVER(inode)->nfs_client;
|
|
struct nfs_delegation *delegation;
|
|
|
|
rcu_read_lock();
|
|
delegation = rcu_dereference(NFS_I(inode)->delegation);
|
|
if (delegation == NULL || memcmp(delegation->stateid.data, stateid->data,
|
|
sizeof(delegation->stateid.data)) != 0) {
|
|
rcu_read_unlock();
|
|
return -ENOENT;
|
|
}
|
|
nfs_mark_return_delegation(clp, delegation);
|
|
rcu_read_unlock();
|
|
nfs_delegation_run_state_manager(clp);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Retrieve the inode associated with a delegation
|
|
*/
|
|
struct inode *nfs_delegation_find_inode(struct nfs_client *clp, const struct nfs_fh *fhandle)
|
|
{
|
|
struct nfs_delegation *delegation;
|
|
struct inode *res = NULL;
|
|
rcu_read_lock();
|
|
list_for_each_entry_rcu(delegation, &clp->cl_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;
|
|
}
|
|
rcu_read_unlock();
|
|
return res;
|
|
}
|
|
|
|
/*
|
|
* Mark all delegations as needing to be reclaimed
|
|
*/
|
|
void nfs_delegation_mark_reclaim(struct nfs_client *clp)
|
|
{
|
|
struct nfs_delegation *delegation;
|
|
rcu_read_lock();
|
|
list_for_each_entry_rcu(delegation, &clp->cl_delegations, super_list)
|
|
set_bit(NFS_DELEGATION_NEED_RECLAIM, &delegation->flags);
|
|
rcu_read_unlock();
|
|
}
|
|
|
|
/*
|
|
* Reap all unclaimed delegations after reboot recovery is done
|
|
*/
|
|
void nfs_delegation_reap_unclaimed(struct nfs_client *clp)
|
|
{
|
|
struct nfs_delegation *delegation;
|
|
struct inode *inode;
|
|
restart:
|
|
rcu_read_lock();
|
|
list_for_each_entry_rcu(delegation, &clp->cl_delegations, super_list) {
|
|
if (test_bit(NFS_DELEGATION_NEED_RECLAIM, &delegation->flags) == 0)
|
|
continue;
|
|
inode = nfs_delegation_grab_inode(delegation);
|
|
if (inode == NULL)
|
|
continue;
|
|
spin_lock(&clp->cl_lock);
|
|
delegation = nfs_detach_delegation_locked(NFS_I(inode), NULL);
|
|
spin_unlock(&clp->cl_lock);
|
|
rcu_read_unlock();
|
|
if (delegation != NULL)
|
|
nfs_free_delegation(delegation);
|
|
iput(inode);
|
|
goto restart;
|
|
}
|
|
rcu_read_unlock();
|
|
}
|
|
|
|
int nfs4_copy_delegation_stateid(nfs4_stateid *dst, struct inode *inode)
|
|
{
|
|
struct nfs_inode *nfsi = NFS_I(inode);
|
|
struct nfs_delegation *delegation;
|
|
int ret = 0;
|
|
|
|
rcu_read_lock();
|
|
delegation = rcu_dereference(nfsi->delegation);
|
|
if (delegation != NULL) {
|
|
memcpy(dst->data, delegation->stateid.data, sizeof(dst->data));
|
|
ret = 1;
|
|
}
|
|
rcu_read_unlock();
|
|
return ret;
|
|
}
|