fs/nfs/delegation.c - kernel/msm-4.9 - Gitiles

 /*
  * linux/fs/nfs/delegation.c
  *
  * Copyright (C) 2004 Trond Myklebust
  *
  * NFS file delegation management
  *
  */
 #include <linux/config.h>
 #include <linux/completion.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"

 static struct nfs_delegation *nfs_alloc_delegation(void)
 {
 	return (struct nfs_delegation *)kmalloc(sizeof(struct nfs_delegation), GFP_KERNEL);
 }

 static void nfs_free_delegation(struct nfs_delegation *delegation)
 {
 	if (delegation->cred)
 		put_rpccred(delegation->cred);
 	kfree(delegation);
 }

 static void nfs_delegation_claim_opens(struct inode *inode)
 {
 	struct nfs_inode *nfsi = NFS_I(inode);
 	struct nfs_open_context *ctx;
 	struct nfs4_state *state;

 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;
 		get_nfs_open_context(ctx);
 		spin_unlock(&inode->i_lock);
 		if (nfs4_open_delegation_recall(ctx->dentry, state) < 0)
 			return;
 		put_nfs_open_context(ctx);
 		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;

 	if (delegation == NULL)
 		return;
 	memcpy(delegation->stateid.data, res->delegation.data,
 			sizeof(delegation->stateid.data));
 	delegation->type = res->delegation_type;
 	delegation->maxsize = res->maxsize;
 	put_rpccred(cred);
 	delegation->cred = get_rpccred(cred);
 	delegation->flags &= ~NFS_DELEGATION_NEED_RECLAIM;
 	NFS_I(inode)->delegation_state = delegation->type;
 	smp_wmb();
 }

 /*
  * Set up a delegation on an inode
  */
 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_inode *nfsi = NFS_I(inode);
 	struct nfs_delegation *delegation;
 	int status = 0;

 	delegation = nfs_alloc_delegation();
 	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->cred = get_rpccred(cred);
 	delegation->inode = inode;

 	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 (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;
 		}
 	}
 	spin_unlock(&clp->cl_lock);
 	if (delegation != NULL)
 		kfree(delegation);
 	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)
 {
 	filemap_fdatawrite(inode->i_mapping);
 	nfs_wb_all(inode);
 	filemap_fdatawait(inode->i_mapping);
 }

 /*
  * Basic procedure for returning a delegation to the server
  */
 int nfs_inode_return_delegation(struct inode *inode)
 {
 	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 */
 	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);
 	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 all delegations associated to a super block
  */
 void nfs_return_all_delegations(struct super_block *sb)
 {
 	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)
 			continue;
 		inode = igrab(delegation->inode);
 		if (inode == NULL)
 			continue;
 		spin_unlock(&clp->cl_lock);
 		nfs_inode_return_delegation(inode);
 		iput(inode);
 		goto restart;
 	}
 	spin_unlock(&clp->cl_lock);
 }

 /*
  * Return all delegations following an NFS4ERR_CB_PATH_DOWN error.
  */
 void nfs_handle_cb_pathdown(struct nfs4_client *clp)
 {
 	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;
 		spin_unlock(&clp->cl_lock);
 		nfs_inode_return_delegation(inode);
 		iput(inode);
 		goto restart;
 	}
 	spin_unlock(&clp->cl_lock);
 }

 struct recall_threadargs {
 	struct inode *inode;
 	struct nfs4_client *clp;
 	const nfs4_stateid *stateid;

 	struct completion started;
 	int result;
 };

 static int recall_thread(void *data)
 {
 	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);
 	struct nfs_delegation *delegation;

 	daemonize("nfsv4-delegreturn");

 	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;
 	}
 	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);

 	if (delegation != NULL)
 		nfs_do_return_delegation(inode, delegation);
 	iput(inode);
 	module_put_and_exit(0);
 }

 /*
  * Asynchronous delegation recall!
  */
 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;
 }

 /*
  * Retrieve the inode associated with a delegation
  */
 struct inode *nfs_delegation_find_inode(struct nfs4_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) {
 			res = igrab(delegation->inode);
 			break;
 		}
 	}
 	spin_unlock(&clp->cl_lock);
 	return res;
 }

 /*
  * Mark all delegations as needing to be reclaimed
  */
 void nfs_delegation_mark_reclaim(struct nfs4_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);
 }

 /*
  * Reap all unclaimed delegations after reboot recovery is done
  */
 void nfs_delegation_reap_unclaimed(struct nfs4_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)
 			continue;
 		list_move(&delegation->super_list, &head);
 		NFS_I(delegation->inode)->delegation = NULL;
 		NFS_I(delegation->inode)->delegation_state = 0;
 	}
 	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);
 	}
 }
	/*
	* linux/fs/nfs/delegation.c
	*
	* Copyright (C) 2004 Trond Myklebust
	*
	* NFS file delegation management
	*
	*/
	#include <linux/config.h>
	#include <linux/completion.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"

	static struct nfs_delegation *nfs_alloc_delegation(void)
	{
	return (struct nfs_delegation *)kmalloc(sizeof(struct nfs_delegation), GFP_KERNEL);
	}

	static void nfs_free_delegation(struct nfs_delegation *delegation)
	{
	if (delegation->cred)
	put_rpccred(delegation->cred);
	kfree(delegation);
	}

	static void nfs_delegation_claim_opens(struct inode *inode)
	{
	struct nfs_inode *nfsi = NFS_I(inode);
	struct nfs_open_context *ctx;
	struct nfs4_state *state;

	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;
	get_nfs_open_context(ctx);
	spin_unlock(&inode->i_lock);
	if (nfs4_open_delegation_recall(ctx->dentry, state) < 0)
	return;
	put_nfs_open_context(ctx);
	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;

	if (delegation == NULL)
	return;
	memcpy(delegation->stateid.data, res->delegation.data,
	sizeof(delegation->stateid.data));
	delegation->type = res->delegation_type;
	delegation->maxsize = res->maxsize;
	put_rpccred(cred);
	delegation->cred = get_rpccred(cred);
	delegation->flags &= ~NFS_DELEGATION_NEED_RECLAIM;
	NFS_I(inode)->delegation_state = delegation->type;
	smp_wmb();
	}

	/*
	* Set up a delegation on an inode
	*/
	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_inode *nfsi = NFS_I(inode);
	struct nfs_delegation *delegation;
	int status = 0;

	delegation = nfs_alloc_delegation();
	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->cred = get_rpccred(cred);
	delegation->inode = inode;

	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 (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;
	}
	}
	spin_unlock(&clp->cl_lock);
	if (delegation != NULL)
	kfree(delegation);
	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)
	{
	filemap_fdatawrite(inode->i_mapping);
	nfs_wb_all(inode);
	filemap_fdatawait(inode->i_mapping);
	}

	/*
	* Basic procedure for returning a delegation to the server
	*/
	int nfs_inode_return_delegation(struct inode *inode)
	{
	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 */
	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);
	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 all delegations associated to a super block
	*/
	void nfs_return_all_delegations(struct super_block *sb)
	{
	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)
	continue;
	inode = igrab(delegation->inode);
	if (inode == NULL)
	continue;
	spin_unlock(&clp->cl_lock);
	nfs_inode_return_delegation(inode);
	iput(inode);
	goto restart;
	}
	spin_unlock(&clp->cl_lock);
	}

	/*
	* Return all delegations following an NFS4ERR_CB_PATH_DOWN error.
	*/
	void nfs_handle_cb_pathdown(struct nfs4_client *clp)
	{
	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;
	spin_unlock(&clp->cl_lock);
	nfs_inode_return_delegation(inode);
	iput(inode);
	goto restart;
	}
	spin_unlock(&clp->cl_lock);
	}

	struct recall_threadargs {
	struct inode *inode;
	struct nfs4_client *clp;
	const nfs4_stateid *stateid;

	struct completion started;
	int result;
	};

	static int recall_thread(void *data)
	{
	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);
	struct nfs_delegation *delegation;

	daemonize("nfsv4-delegreturn");

	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;
	}
	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);

	if (delegation != NULL)
	nfs_do_return_delegation(inode, delegation);
	iput(inode);
	module_put_and_exit(0);
	}

	/*
	* Asynchronous delegation recall!
	*/
	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;
	}

	/*
	* Retrieve the inode associated with a delegation
	*/
	struct inode nfs_delegation_find_inode(struct nfs4_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) {
	res = igrab(delegation->inode);
	break;
	}
	}
	spin_unlock(&clp->cl_lock);
	return res;
	}

	/*
	* Mark all delegations as needing to be reclaimed
	*/
	void nfs_delegation_mark_reclaim(struct nfs4_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);
	}

	/*
	* Reap all unclaimed delegations after reboot recovery is done
	*/
	void nfs_delegation_reap_unclaimed(struct nfs4_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)
	continue;
	list_move(&delegation->super_list, &head);
	NFS_I(delegation->inode)->delegation = NULL;
	NFS_I(delegation->inode)->delegation_state = 0;
	}
	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);
	}
	}