* NFS file delegation management
*
*/
-#include <linux/config.h>
#include <linux/completion.h>
+#include <linux/kthread.h>
#include <linux/module.h>
#include <linux/sched.h>
+#include <linux/smp_lock.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 struct nfs_delegation *nfs_alloc_delegation(void)
+static void nfs_do_free_delegation(struct nfs_delegation *delegation)
{
- return (struct nfs_delegation *)kmalloc(sizeof(struct nfs_delegation), GFP_KERNEL);
+ 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)
{
- if (delegation->cred)
- put_rpccred(delegation->cred);
- kfree(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 = 0;
+
+ if (inode->i_flock == NULL)
+ goto out;
+
+ /* Protect inode->i_flock using the BKL */
+ lock_kernel();
+ 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_kernel();
+ status = nfs4_lock_delegation_recall(state, fl);
+ if (status < 0)
+ goto out;
+ lock_kernel();
+ }
+ unlock_kernel();
+out:
+ return status;
}
-static void nfs_delegation_claim_opens(struct inode *inode)
+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);
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);
- if (nfs4_open_delegation_recall(ctx->dentry, state) < 0)
- return;
+ 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);
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;
sizeof(delegation->stateid.data));
delegation->type = res->delegation_type;
delegation->maxsize = res->maxsize;
- put_rpccred(cred);
+ oldcred = delegation->cred;
delegation->cred = get_rpccred(cred);
- delegation->flags &= ~NFS_DELEGATION_NEED_RECLAIM;
+ 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;
}
/*
*/
int nfs_inode_set_delegation(struct inode *inode, struct rpc_cred *cred, struct nfs_openres *res)
{
- struct nfs4_client *clp = NFS_SERVER(inode)->nfs4_state;
+ 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 = nfs_alloc_delegation();
+ 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 (nfsi->delegation == NULL) {
- list_add(&delegation->super_list, &clp->cl_delegations);
- nfsi->delegation = delegation;
- nfsi->delegation_state = delegation->type;
- delegation = NULL;
- } else {
+ if (rcu_dereference(nfsi->delegation) != NULL) {
if (memcmp(&delegation->stateid, &nfsi->delegation->stateid,
- sizeof(delegation->stateid)) != 0 ||
- delegation->type != nfsi->delegation->type) {
- printk("%s: server %u.%u.%u.%u, handed out a duplicate delegation!\n",
- __FUNCTION__, NIPQUAD(clp->cl_addr));
- status = -EIO;
+ 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)
- kfree(delegation);
+ nfs_free_delegation(delegation);
+ if (freeme != NULL)
+ nfs_do_return_delegation(inode, freeme, 0);
return status;
}
-static int nfs_do_return_delegation(struct inode *inode, struct nfs_delegation *delegation)
-{
- int res = 0;
-
- __nfs_revalidate_inode(NFS_SERVER(inode), inode);
-
- res = nfs4_proc_delegreturn(inode, delegation->cred, &delegation->stateid);
- nfs_free_delegation(delegation);
- return res;
-}
-
/* Sync all data to disk upon delegation return */
static void nfs_msync_inode(struct inode *inode)
{
/*
* Basic procedure for returning a delegation to the server
*/
-int nfs_inode_return_delegation(struct inode *inode)
+static int __nfs_inode_return_delegation(struct inode *inode, struct nfs_delegation *delegation)
{
- struct nfs4_client *clp = NFS_SERVER(inode)->nfs4_state;
struct nfs_inode *nfsi = NFS_I(inode);
- struct nfs_delegation *delegation;
- int res = 0;
nfs_msync_inode(inode);
- down_read(&clp->cl_sem);
- /* Guard against new delegated open calls */
+ /*
+ * Guard against new delegated open/lock/unlock calls and against
+ * state recovery
+ */
down_write(&nfsi->rwsem);
- spin_lock(&clp->cl_lock);
- delegation = nfsi->delegation;
- if (delegation != NULL) {
- list_del_init(&delegation->super_list);
- nfsi->delegation = NULL;
- nfsi->delegation_state = 0;
- }
- spin_unlock(&clp->cl_lock);
- nfs_delegation_claim_opens(inode);
+ nfs_delegation_claim_opens(inode, &delegation->stateid);
up_write(&nfsi->rwsem);
- up_read(&clp->cl_sem);
nfs_msync_inode(inode);
- if (delegation != NULL)
- res = nfs_do_return_delegation(inode, delegation);
- return res;
+ return nfs_do_return_delegation(inode, delegation, 1);
}
/*
- * Return all delegations associated to a super block
+ * Return all delegations that have been marked for return
*/
-void nfs_return_all_delegations(struct super_block *sb)
+void nfs_client_return_marked_delegations(struct nfs_client *clp)
{
- struct nfs4_client *clp = NFS_SB(sb)->nfs4_state;
struct nfs_delegation *delegation;
struct inode *inode;
- if (clp == NULL)
- return;
restart:
- spin_lock(&clp->cl_lock);
- list_for_each_entry(delegation, &clp->cl_delegations, super_list) {
- if (delegation->inode->i_sb != sb)
+ 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 = igrab(delegation->inode);
+ 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);
- nfs_inode_return_delegation(inode);
+ rcu_read_unlock();
+ if (delegation != NULL)
+ __nfs_inode_return_delegation(inode, delegation);
iput(inode);
goto restart;
}
- spin_unlock(&clp->cl_lock);
+ rcu_read_unlock();
}
/*
- * Return all delegations following an NFS4ERR_CB_PATH_DOWN error.
+ * 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_handle_cb_pathdown(struct nfs4_client *clp)
+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;
- struct inode *inode;
- if (clp == NULL)
- return;
-restart:
- spin_lock(&clp->cl_lock);
- list_for_each_entry(delegation, &clp->cl_delegations, super_list) {
- inode = igrab(delegation->inode);
- if (inode == NULL)
- continue;
+ if (rcu_dereference(nfsi->delegation) != NULL) {
+ spin_lock(&clp->cl_lock);
+ delegation = nfs_detach_delegation_locked(nfsi, NULL);
spin_unlock(&clp->cl_lock);
- nfs_inode_return_delegation(inode);
- iput(inode);
- goto restart;
+ if (delegation != NULL)
+ nfs_do_return_delegation(inode, delegation, 0);
}
- spin_unlock(&clp->cl_lock);
}
-struct recall_threadargs {
- struct inode *inode;
- struct nfs4_client *clp;
- const nfs4_stateid *stateid;
+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;
- struct completion started;
- int result;
-};
+ 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 int recall_thread(void *data)
+static void nfs_mark_return_delegation(struct nfs_client *clp, struct nfs_delegation *delegation)
{
- struct recall_threadargs *args = (struct recall_threadargs *)data;
- struct inode *inode = igrab(args->inode);
- struct nfs4_client *clp = NFS_SERVER(inode)->nfs4_state;
- struct nfs_inode *nfsi = NFS_I(inode);
+ 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;
- daemonize("nfsv4-delegreturn");
+ 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;
- nfs_msync_inode(inode);
- down_read(&clp->cl_sem);
- down_write(&nfsi->rwsem);
- spin_lock(&clp->cl_lock);
- delegation = nfsi->delegation;
- if (delegation != NULL && memcmp(delegation->stateid.data,
- args->stateid->data,
- sizeof(delegation->stateid.data)) == 0) {
- list_del_init(&delegation->super_list);
- nfsi->delegation = NULL;
- nfsi->delegation_state = 0;
- args->result = 0;
- } else {
- delegation = NULL;
- args->result = -ENOENT;
+ 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);
}
- spin_unlock(&clp->cl_lock);
- complete(&args->started);
- nfs_delegation_claim_opens(inode);
- up_write(&nfsi->rwsem);
- up_read(&clp->cl_sem);
- nfs_msync_inode(inode);
+ rcu_read_unlock();
+}
- if (delegation != NULL)
- nfs_do_return_delegation(inode, delegation);
- iput(inode);
- module_put_and_exit(0);
+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);
}
/*
*/
int nfs_async_inode_return_delegation(struct inode *inode, const nfs4_stateid *stateid)
{
- struct recall_threadargs data = {
- .inode = inode,
- .stateid = stateid,
- };
- int status;
-
- init_completion(&data.started);
- __module_get(THIS_MODULE);
- status = kernel_thread(recall_thread, &data, CLONE_KERNEL);
- if (status < 0)
- goto out_module_put;
- wait_for_completion(&data.started);
- return data.result;
-out_module_put:
- module_put(THIS_MODULE);
- return status;
+ 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 nfs4_client *clp, const struct nfs_fh *fhandle)
+struct inode *nfs_delegation_find_inode(struct nfs_client *clp, const struct nfs_fh *fhandle)
{
struct nfs_delegation *delegation;
struct inode *res = NULL;
- spin_lock(&clp->cl_lock);
- list_for_each_entry(delegation, &clp->cl_delegations, super_list) {
- if (nfs_compare_fh(fhandle, &NFS_I(delegation->inode)->fh) == 0) {
+ 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);
- break;
}
+ spin_unlock(&delegation->lock);
+ if (res != NULL)
+ break;
}
- spin_unlock(&clp->cl_lock);
+ rcu_read_unlock();
return res;
}
/*
* Mark all delegations as needing to be reclaimed
*/
-void nfs_delegation_mark_reclaim(struct nfs4_client *clp)
+void nfs_delegation_mark_reclaim(struct nfs_client *clp)
{
struct nfs_delegation *delegation;
- spin_lock(&clp->cl_lock);
- list_for_each_entry(delegation, &clp->cl_delegations, super_list)
- delegation->flags |= NFS_DELEGATION_NEED_RECLAIM;
- spin_unlock(&clp->cl_lock);
+ 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 nfs4_client *clp)
+void nfs_delegation_reap_unclaimed(struct nfs_client *clp)
{
- struct nfs_delegation *delegation, *n;
- LIST_HEAD(head);
- spin_lock(&clp->cl_lock);
- list_for_each_entry_safe(delegation, n, &clp->cl_delegations, super_list) {
- if ((delegation->flags & NFS_DELEGATION_NEED_RECLAIM) == 0)
+ 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;
- list_move(&delegation->super_list, &head);
- NFS_I(delegation->inode)->delegation = NULL;
- NFS_I(delegation->inode)->delegation_state = 0;
+ 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;
}
- spin_unlock(&clp->cl_lock);
- while(!list_empty(&head)) {
- delegation = list_entry(head.next, struct nfs_delegation, super_list);
- list_del(&delegation->super_list);
- nfs_free_delegation(delegation);
+ 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;
}
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff