Commit df24ac7a authored by Dai Ngo's avatar Dai Ngo Committed by Chuck Lever
Browse files

NFSD: enhance inter-server copy cleanup 



Currently nfsd4_setup_inter_ssc returns the vfsmount of the source
server's export when the mount completes. After the copy is done
nfsd4_cleanup_inter_ssc is called with the vfsmount of the source
server and it searches nfsd_ssc_mount_list for a matching entry
to do the clean up.

The problems with this approach are (1) the need to search the
nfsd_ssc_mount_list and (2) the code has to handle the case where
the matching entry is not found which looks ugly.

The enhancement is instead of nfsd4_setup_inter_ssc returning the
vfsmount, it returns the nfsd4_ssc_umount_item which has the
vfsmount embedded in it. When nfsd4_cleanup_inter_ssc is called
it's passed with the nfsd4_ssc_umount_item directly to do the
clean up so no searching is needed and there is no need to handle
the 'not found' case.

Signed-off-by: default avatarDai Ngo <dai.ngo@oracle.com>
Signed-off-by: default avatarChuck Lever <chuck.lever@oracle.com>
[ cel: adjusted whitespace and variable/function names ]
Reviewed-by: default avatarOlga Kornievskaia <kolga@netapp.com>
parent f4afc8fe

fs/nfsd/nfs4proc.c

+44 −67
Original line number Diff line number Diff line
@@ -1293,15 +1293,15 @@ extern void nfs_sb_deactive(struct super_block *sb); 
 * setup a work entry in the ssc delayed unmount list.

 */

static __be32 nfsd4_ssc_setup_dul(struct nfsd_net *nn, char *ipaddr,

		struct nfsd4_ssc_umount_item **retwork, struct vfsmount **ss_mnt)

				  struct nfsd4_ssc_umount_item **nsui)

{

	struct nfsd4_ssc_umount_item *ni = NULL;

	struct nfsd4_ssc_umount_item *work = NULL;

	struct nfsd4_ssc_umount_item *tmp;

	DEFINE_WAIT(wait);

	__be32 status = 0;



	*ss_mnt = NULL;

	*retwork = NULL;

	*nsui = NULL;

	work = kzalloc(sizeof(*work), GFP_KERNEL);

try_again:

	spin_lock(&nn->nfsd_ssc_lock);
@@ -1325,12 +1325,12 @@ static __be32 nfsd4_ssc_setup_dul(struct nfsd_net *nn, char *ipaddr, 
			finish_wait(&nn->nfsd_ssc_waitq, &wait);

			goto try_again;

		}

		*ss_mnt = ni->nsui_vfsmount;

		*nsui = ni;

		refcount_inc(&ni->nsui_refcnt);

		spin_unlock(&nn->nfsd_ssc_lock);

		kfree(work);



		/* return vfsmount in ss_mnt */

		/* return vfsmount in (*nsui)->nsui_vfsmount */

		return 0;

	}

	if (work) {
@@ -1338,31 +1338,32 @@ static __be32 nfsd4_ssc_setup_dul(struct nfsd_net *nn, char *ipaddr, 
		refcount_set(&work->nsui_refcnt, 2);

		work->nsui_busy = true;

		list_add_tail(&work->nsui_list, &nn->nfsd_ssc_mount_list);

		*retwork = work;

	}

		*nsui = work;

	} else

		status = nfserr_resource;

	spin_unlock(&nn->nfsd_ssc_lock);

	return 0;

	return status;

}



static void nfsd4_ssc_update_dul_work(struct nfsd_net *nn,

		struct nfsd4_ssc_umount_item *work, struct vfsmount *ss_mnt)

static void nfsd4_ssc_update_dul(struct nfsd_net *nn,

				 struct nfsd4_ssc_umount_item *nsui,

				 struct vfsmount *ss_mnt)

{

	/* set nsui_vfsmount, clear busy flag and wakeup waiters */

	spin_lock(&nn->nfsd_ssc_lock);

	work->nsui_vfsmount = ss_mnt;

	work->nsui_busy = false;

	nsui->nsui_vfsmount = ss_mnt;

	nsui->nsui_busy = false;

	wake_up_all(&nn->nfsd_ssc_waitq);

	spin_unlock(&nn->nfsd_ssc_lock);

}



static void nfsd4_ssc_cancel_dul_work(struct nfsd_net *nn,

		struct nfsd4_ssc_umount_item *work)

static void nfsd4_ssc_cancel_dul(struct nfsd_net *nn,

				 struct nfsd4_ssc_umount_item *nsui)

{

	spin_lock(&nn->nfsd_ssc_lock);

	list_del(&work->nsui_list);

	list_del(&nsui->nsui_list);

	wake_up_all(&nn->nfsd_ssc_waitq);

	spin_unlock(&nn->nfsd_ssc_lock);

	kfree(work);

	kfree(nsui);

}



/*
@@ -1370,7 +1371,7 @@ static void nfsd4_ssc_cancel_dul_work(struct nfsd_net *nn, 
 */

static __be32

nfsd4_interssc_connect(struct nl4_server *nss, struct svc_rqst *rqstp,

		       struct vfsmount **mount)

		       struct nfsd4_ssc_umount_item **nsui)

{

	struct file_system_type *type;

	struct vfsmount *ss_mnt;
@@ -1381,7 +1382,6 @@ nfsd4_interssc_connect(struct nl4_server *nss, struct svc_rqst *rqstp, 
	char *ipaddr, *dev_name, *raw_data;

	int len, raw_len;

	__be32 status = nfserr_inval;

	struct nfsd4_ssc_umount_item *work = NULL;

	struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id);



	naddr = &nss->u.nl4_addr;
@@ -1389,6 +1389,7 @@ nfsd4_interssc_connect(struct nl4_server *nss, struct svc_rqst *rqstp, 
					 naddr->addr_len,

					 (struct sockaddr *)&tmp_addr,

					 sizeof(tmp_addr));

	*nsui = NULL;

	if (tmp_addrlen == 0)

		goto out_err;
@@ -1431,10 +1432,10 @@ nfsd4_interssc_connect(struct nl4_server *nss, struct svc_rqst *rqstp, 
		goto out_free_rawdata;

	snprintf(dev_name, len + 5, "%s%s%s:/", startsep, ipaddr, endsep);



	status = nfsd4_ssc_setup_dul(nn, ipaddr, &work, &ss_mnt);

	status = nfsd4_ssc_setup_dul(nn, ipaddr, nsui);

	if (status)

		goto out_free_devname;

	if (ss_mnt)

	if ((*nsui)->nsui_vfsmount)

		goto out_done;



	/* Use an 'internal' mount: SB_KERNMOUNT -> MNT_INTERNAL */
@@ -1442,15 +1443,12 @@ nfsd4_interssc_connect(struct nl4_server *nss, struct svc_rqst *rqstp, 
	module_put(type->owner);

	if (IS_ERR(ss_mnt)) {

		status = nfserr_nodev;

		if (work)

			nfsd4_ssc_cancel_dul_work(nn, work);

		nfsd4_ssc_cancel_dul(nn, *nsui);

		goto out_free_devname;

	}

	if (work)

		nfsd4_ssc_update_dul_work(nn, work, ss_mnt);

	nfsd4_ssc_update_dul(nn, *nsui, ss_mnt);

out_done:

	status = 0;

	*mount = ss_mnt;



out_free_devname:

	kfree(dev_name);
@@ -1474,7 +1472,7 @@ nfsd4_interssc_connect(struct nl4_server *nss, struct svc_rqst *rqstp, 
static __be32

nfsd4_setup_inter_ssc(struct svc_rqst *rqstp,

		      struct nfsd4_compound_state *cstate,

		      struct nfsd4_copy *copy, struct vfsmount **mount)

		      struct nfsd4_copy *copy)

{

	struct svc_fh *s_fh = NULL;

	stateid_t *s_stid = &copy->cp_src_stateid;
@@ -1487,7 +1485,7 @@ nfsd4_setup_inter_ssc(struct svc_rqst *rqstp, 
	if (status)

		goto out;



	status = nfsd4_interssc_connect(copy->cp_src, rqstp, mount);

	status = nfsd4_interssc_connect(copy->cp_src, rqstp, &copy->ss_nsui);

	if (status)

		goto out;
@@ -1505,45 +1503,27 @@ nfsd4_setup_inter_ssc(struct svc_rqst *rqstp, 
}



static void

nfsd4_cleanup_inter_ssc(struct vfsmount *ss_mnt, struct file *filp,

nfsd4_cleanup_inter_ssc(struct nfsd4_ssc_umount_item *nsui, struct file *filp,

			struct nfsd_file *dst)

{

	bool found = false;

	long timeout;

	struct nfsd4_ssc_umount_item *tmp;

	struct nfsd4_ssc_umount_item *ni = NULL;

	struct nfsd_net *nn = net_generic(dst->nf_net, nfsd_net_id);

	long timeout = msecs_to_jiffies(nfsd4_ssc_umount_timeout);



	nfs42_ssc_close(filp);

	nfsd_file_put(dst);

	fput(filp);



	if (!nn) {

		mntput(ss_mnt);

		return;

	}

	spin_lock(&nn->nfsd_ssc_lock);

	timeout = msecs_to_jiffies(nfsd4_ssc_umount_timeout);

	list_for_each_entry_safe(ni, tmp, &nn->nfsd_ssc_mount_list, nsui_list) {

		if (ni->nsui_vfsmount->mnt_sb == ss_mnt->mnt_sb) {

			list_del(&ni->nsui_list);

	list_del(&nsui->nsui_list);

	/*

	 * vfsmount can be shared by multiple exports,

	 * decrement refcnt. If the count drops to 1 it

	 * will be unmounted when nsui_expire expires.

	 */

			refcount_dec(&ni->nsui_refcnt);

			ni->nsui_expire = jiffies + timeout;

			list_add_tail(&ni->nsui_list, &nn->nfsd_ssc_mount_list);

			found = true;

			break;

		}

	}

	refcount_dec(&nsui->nsui_refcnt);

	nsui->nsui_expire = jiffies + timeout;

	list_add_tail(&nsui->nsui_list, &nn->nfsd_ssc_mount_list);

	spin_unlock(&nn->nfsd_ssc_lock);

	if (!found) {

		mntput(ss_mnt);

		return;

	}

}



#else /* CONFIG_NFSD_V4_2_INTER_SSC */
@@ -1551,15 +1531,13 @@ nfsd4_cleanup_inter_ssc(struct vfsmount *ss_mnt, struct file *filp, 
static __be32

nfsd4_setup_inter_ssc(struct svc_rqst *rqstp,

		      struct nfsd4_compound_state *cstate,

		      struct nfsd4_copy *copy,

		      struct vfsmount **mount)

		      struct nfsd4_copy *copy)

{

	*mount = NULL;

	return nfserr_inval;

}



static void

nfsd4_cleanup_inter_ssc(struct vfsmount *ss_mnt, struct file *filp,

nfsd4_cleanup_inter_ssc(struct nfsd4_ssc_umount_item *nsui, struct file *filp,

			struct nfsd_file *dst)

{

}
@@ -1700,7 +1678,7 @@ static void dup_copy_fields(struct nfsd4_copy *src, struct nfsd4_copy *dst) 
	memcpy(dst->cp_src, src->cp_src, sizeof(struct nl4_server));

	memcpy(&dst->stateid, &src->stateid, sizeof(src->stateid));

	memcpy(&dst->c_fh, &src->c_fh, sizeof(src->c_fh));

	dst->ss_mnt = src->ss_mnt;

	dst->ss_nsui = src->ss_nsui;

}



static void cleanup_async_copy(struct nfsd4_copy *copy)
@@ -1749,8 +1727,8 @@ static int nfsd4_do_async_copy(void *data) 
	if (nfsd4_ssc_is_inter(copy)) {

		struct file *filp;



		filp = nfs42_ssc_open(copy->ss_mnt, &copy->c_fh,

				      &copy->stateid);

		filp = nfs42_ssc_open(copy->ss_nsui->nsui_vfsmount,

				      &copy->c_fh, &copy->stateid);

		if (IS_ERR(filp)) {

			switch (PTR_ERR(filp)) {

			case -EBADF:
@@ -1764,7 +1742,7 @@ static int nfsd4_do_async_copy(void *data) 
		}

		nfserr = nfsd4_do_copy(copy, filp, copy->nf_dst->nf_file,

				       false);

		nfsd4_cleanup_inter_ssc(copy->ss_mnt, filp, copy->nf_dst);

		nfsd4_cleanup_inter_ssc(copy->ss_nsui, filp, copy->nf_dst);

	} else {

		nfserr = nfsd4_do_copy(copy, copy->nf_src->nf_file,

				       copy->nf_dst->nf_file, false);
@@ -1790,8 +1768,7 @@ nfsd4_copy(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate, 
			status = nfserr_notsupp;

			goto out;

		}

		status = nfsd4_setup_inter_ssc(rqstp, cstate, copy,

				&copy->ss_mnt);

		status = nfsd4_setup_inter_ssc(rqstp, cstate, copy);

		if (status)

			return nfserr_offload_denied;

	} else {

fs/nfsd/xdr4.h

+1 −1
Original line number Diff line number Diff line
@@ -571,7 +571,7 @@ struct nfsd4_copy { 
	struct task_struct	*copy_task;

	refcount_t		refcount;



	struct vfsmount		*ss_mnt;

	struct nfsd4_ssc_umount_item *ss_nsui;

	struct nfs_fh		c_fh;

	nfs4_stateid		stateid;

};

include/linux/nfs_ssc.h

+1 −1
Original line number Diff line number Diff line
@@ -53,6 +53,7 @@ static inline void nfs42_ssc_close(struct file *filep) 
	if (nfs_ssc_client_tbl.ssc_nfs4_ops)

		(*nfs_ssc_client_tbl.ssc_nfs4_ops->sco_close)(filep);

}

#endif



struct nfsd4_ssc_umount_item {

	struct list_head nsui_list;
@@ -66,7 +67,6 @@ struct nfsd4_ssc_umount_item { 
	struct vfsmount *nsui_vfsmount;

	char nsui_ipaddr[RPC_MAX_ADDRBUFLEN + 1];

};

#endif



/*

 * NFS_FS