Commit 974cec8c authored by Andy Adamson's avatar Andy Adamson Committed by Trond Myklebust
Browse files

NFS: client needs to maintain list of inodes with active layouts 



In particular, server reboot will invalidate all layouts.

Note that in order to have an active layout, we must get a successful response
from the server.  To avoid adding that machinery, this patch just includes a
stub that fakes up a successful return.  Since the layout is never referenced
for io, this is not a problem.

Signed-off-by: default avatarAndy Adamson <andros@netapp.com>
Signed-off-by: default avatarBenny Halevy <bhalevy@panasas.com>
Signed-off-by: default avatarDean Hildebrand <dhildebz@umich.edu>
Signed-off-by: default avatarFred Isaman <iisaman@netapp.com>
Signed-off-by: default avatarTrond Myklebust <Trond.Myklebust@netapp.com>
parent e5e94017

fs/nfs/client.c

+3 −1
Original line number Diff line number Diff line
@@ -156,7 +156,9 @@ static struct nfs_client *nfs_alloc_client(const struct nfs_client_initdata *cl_ 
	cred = rpc_lookup_machine_cred();

	if (!IS_ERR(cred))

		clp->cl_machine_cred = cred;



#if defined(CONFIG_NFS_V4_1)

	INIT_LIST_HEAD(&clp->cl_layouts);

#endif

	nfs_fscache_get_client_cookie(clp);



	return clp;

fs/nfs/nfs4state.c

+2 −0
Original line number Diff line number Diff line
@@ -54,6 +54,7 @@ 
#include "callback.h"

#include "delegation.h"

#include "internal.h"

#include "pnfs.h"



#define OPENOWNER_POOL_SIZE	8
@@ -1475,6 +1476,7 @@ static void nfs4_state_manager(struct nfs_client *clp) 
			}

			clear_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);

			set_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state);

			pnfs_destroy_all_layouts(clp);

		}



		if (test_and_clear_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state)) {

fs/nfs/pnfs.c

+157 −3
Original line number Diff line number Diff line
@@ -28,6 +28,7 @@ 
 */



#include <linux/nfs_fs.h>

#include "internal.h"

#include "pnfs.h"



#define NFSDBG_FACILITY		NFSDBG_PNFS
@@ -183,39 +184,190 @@ put_layout_hdr_locked(struct pnfs_layout_hdr *lo) 
	lo->refcount--;

	if (!lo->refcount) {

		dprintk("%s: freeing layout cache %p\n", __func__, lo);

		BUG_ON(!list_empty(&lo->layouts));

		NFS_I(lo->inode)->layout = NULL;

		kfree(lo);

	}

}



static void

put_layout_hdr(struct inode *inode)

{

	spin_lock(&inode->i_lock);

	put_layout_hdr_locked(NFS_I(inode)->layout);

	spin_unlock(&inode->i_lock);

}



static void

init_lseg(struct pnfs_layout_hdr *lo, struct pnfs_layout_segment *lseg)

{

	INIT_LIST_HEAD(&lseg->fi_list);

	kref_init(&lseg->kref);

	lseg->layout = lo;

}



/* Called without i_lock held, as the free_lseg call may sleep */

static void

destroy_lseg(struct kref *kref)

{

	struct pnfs_layout_segment *lseg =

		container_of(kref, struct pnfs_layout_segment, kref);

	struct inode *ino = lseg->layout->inode;



	dprintk("--> %s\n", __func__);

	kfree(lseg);

	/* Matched by get_layout_hdr_locked in pnfs_insert_layout */

	put_layout_hdr(ino);

}



static void

put_lseg(struct pnfs_layout_segment *lseg)

{

	if (!lseg)

		return;



	dprintk("%s: lseg %p ref %d\n", __func__, lseg,

		atomic_read(&lseg->kref.refcount));

	kref_put(&lseg->kref, destroy_lseg);

}



static void

pnfs_clear_lseg_list(struct pnfs_layout_hdr *lo, struct list_head *tmp_list)

{

	struct pnfs_layout_segment *lseg, *next;

	struct nfs_client *clp;



	dprintk("%s:Begin lo %p\n", __func__, lo);



	assert_spin_locked(&lo->inode->i_lock);

	list_for_each_entry_safe(lseg, next, &lo->segs, fi_list) {

		dprintk("%s: freeing lseg %p\n", __func__, lseg);

		list_move(&lseg->fi_list, tmp_list);

	}

	clp = NFS_SERVER(lo->inode)->nfs_client;

	spin_lock(&clp->cl_lock);

	/* List does not take a reference, so no need for put here */

	list_del_init(&lo->layouts);

	spin_unlock(&clp->cl_lock);



	dprintk("%s:Return\n", __func__);

}



static void

pnfs_free_lseg_list(struct list_head *tmp_list)

{

	struct pnfs_layout_segment *lseg;



	while (!list_empty(tmp_list)) {

		lseg = list_entry(tmp_list->next, struct pnfs_layout_segment,

				fi_list);

		dprintk("%s calling put_lseg on %p\n", __func__, lseg);

		list_del(&lseg->fi_list);

		put_lseg(lseg);

	}

}



void

pnfs_destroy_layout(struct nfs_inode *nfsi)

{

	struct pnfs_layout_hdr *lo;

	LIST_HEAD(tmp_list);



	spin_lock(&nfsi->vfs_inode.i_lock);

	lo = nfsi->layout;

	if (lo) {

		pnfs_clear_lseg_list(lo, &tmp_list);

		/* Matched by refcount set to 1 in alloc_init_layout_hdr */

		put_layout_hdr_locked(lo);

	}

	spin_unlock(&nfsi->vfs_inode.i_lock);

	pnfs_free_lseg_list(&tmp_list);

}



/* STUB - pretend LAYOUTGET to server failed */

/*

 * Called by the state manger to remove all layouts established under an

 * expired lease.

 */

void

pnfs_destroy_all_layouts(struct nfs_client *clp)

{

	struct pnfs_layout_hdr *lo;

	LIST_HEAD(tmp_list);



	spin_lock(&clp->cl_lock);

	list_splice_init(&clp->cl_layouts, &tmp_list);

	spin_unlock(&clp->cl_lock);



	while (!list_empty(&tmp_list)) {

		lo = list_entry(tmp_list.next, struct pnfs_layout_hdr,

				layouts);

		dprintk("%s freeing layout for inode %lu\n", __func__,

			lo->inode->i_ino);

		pnfs_destroy_layout(NFS_I(lo->inode));

	}

}



static void pnfs_insert_layout(struct pnfs_layout_hdr *lo,

			       struct pnfs_layout_segment *lseg);



/* Get layout from server. */

static struct pnfs_layout_segment *

send_layoutget(struct pnfs_layout_hdr *lo,

	   struct nfs_open_context *ctx,

	   u32 iomode)

{

	struct inode *ino = lo->inode;

	struct pnfs_layout_segment *lseg;



	/* Lets pretend we sent LAYOUTGET and got a response */

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

	if (!lseg) {

		set_bit(lo_fail_bit(iomode), &lo->state);

		spin_lock(&ino->i_lock);

		put_layout_hdr_locked(lo);

		spin_unlock(&ino->i_lock);

		return NULL;

	}

	init_lseg(lo, lseg);

	lseg->iomode = IOMODE_RW;

	spin_lock(&ino->i_lock);

	pnfs_insert_layout(lo, lseg);

	put_layout_hdr_locked(lo);

	spin_unlock(&ino->i_lock);

	return lseg;

}



static void

pnfs_insert_layout(struct pnfs_layout_hdr *lo,

		   struct pnfs_layout_segment *lseg)

{

	dprintk("%s:Begin\n", __func__);



	assert_spin_locked(&lo->inode->i_lock);

	if (list_empty(&lo->segs)) {

		struct nfs_client *clp = NFS_SERVER(lo->inode)->nfs_client;



		spin_lock(&clp->cl_lock);

		BUG_ON(!list_empty(&lo->layouts));

		list_add_tail(&lo->layouts, &clp->cl_layouts);

		spin_unlock(&clp->cl_lock);

	}

	get_layout_hdr_locked(lo);

	/* STUB - add the constructed lseg if necessary */

	if (list_empty(&lo->segs)) {

		list_add_tail(&lseg->fi_list, &lo->segs);

		dprintk("%s: inserted lseg %p iomode %d at tail\n",

			__func__, lseg, lseg->iomode);

	} else {

		/* There is no harm for the moment in calling this

		 * with the lock held, and the call will be removed

		 * with the STUB.

		 */

		put_lseg(lseg);

	}



	dprintk("%s:Return\n", __func__);

}



static struct pnfs_layout_hdr *

alloc_init_layout_hdr(struct inode *ino)
@@ -226,6 +378,8 @@ alloc_init_layout_hdr(struct inode *ino) 
	if (!lo)

		return NULL;

	lo->refcount = 1;

	INIT_LIST_HEAD(&lo->layouts);

	INIT_LIST_HEAD(&lo->segs);

	lo->inode = ino;

	return lo;

}

fs/nfs/pnfs.h

+14 −0
Original line number Diff line number Diff line
@@ -30,6 +30,13 @@ 
#ifndef FS_NFS_PNFS_H

#define FS_NFS_PNFS_H



struct pnfs_layout_segment {

	struct list_head fi_list;

	u32 iomode;

	struct kref kref;

	struct pnfs_layout_hdr *layout;

};



#ifdef CONFIG_NFS_V4_1



#define LAYOUT_NFSV4_1_MODULE_PREFIX "nfs-layouttype4"
@@ -51,6 +58,8 @@ struct pnfs_layoutdriver_type { 


struct pnfs_layout_hdr {

	unsigned long		refcount;

	struct list_head	layouts;   /* other client layouts */

	struct list_head	segs;      /* layout segments list */

	unsigned long		state;

	struct inode		*inode;

};
@@ -64,6 +73,7 @@ pnfs_update_layout(struct inode *ino, struct nfs_open_context *ctx, 
void set_pnfs_layoutdriver(struct nfs_server *, u32 id);

void unset_pnfs_layoutdriver(struct nfs_server *);

void pnfs_destroy_layout(struct nfs_inode *);

void pnfs_destroy_all_layouts(struct nfs_client *);





static inline int lo_fail_bit(u32 iomode)
@@ -80,6 +90,10 @@ static inline int pnfs_enabled_sb(struct nfs_server *nfss) 


#else  /* CONFIG_NFS_V4_1 */



static inline void pnfs_destroy_all_layouts(struct nfs_client *clp)

{

}



static inline void pnfs_destroy_layout(struct nfs_inode *nfsi)

{

}

include/linux/nfs_fs_sb.h

+1 −0
Original line number Diff line number Diff line
@@ -82,6 +82,7 @@ struct nfs_client { 
	/* The flags used for obtaining the clientid during EXCHANGE_ID */

	u32			cl_exchange_flags;

	struct nfs4_session	*cl_session; 	/* sharred session */

	struct list_head	cl_layouts;

#endif /* CONFIG_NFS_V4_1 */



#ifdef CONFIG_NFS_FSCACHE

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