Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit d684d2ae authored by Fred Isaman's avatar Fred Isaman Committed by Trond Myklebust
Browse files

NFSv4.1: lseg refcounting 



Prepare put_lseg and get_lseg to be called from the pNFS I/O code.
Pull common code from pnfs_lseg_locked to call from pnfs_lseg.
Inline pnfs_lseg_locked into it's only caller.

Signed-off-by: default avatarFred Isaman <iisaman@netapp.com>
Signed-off-by: default avatarBenny Halevy <bhalevy@panasas.com>
Signed-off-by: default avatarTrond Myklebust <Trond.Myklebust@netapp.com>
parent 94de8b27

fs/nfs/pnfs.c

+39 −23
Original line number Diff line number Diff line
@@ -230,32 +230,41 @@ static void free_lseg(struct pnfs_layout_segment *lseg) 
	put_layout_hdr(NFS_I(ino)->layout);

}



/* The use of tmp_list is necessary because pnfs_curr_ld->free_lseg

 * could sleep, so must be called outside of the lock.

 * Returns 1 if object was removed, otherwise return 0.

 */

static int

put_lseg_locked(struct pnfs_layout_segment *lseg,

		struct list_head *tmp_list)

static void

put_lseg_common(struct pnfs_layout_segment *lseg)

{

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

		atomic_read(&lseg->pls_refcount),

		test_bit(NFS_LSEG_VALID, &lseg->pls_flags));

	if (atomic_dec_and_test(&lseg->pls_refcount)) {

		struct inode *ino = lseg->pls_layout->plh_inode;

	struct inode *inode = lseg->pls_layout->plh_inode;



	BUG_ON(test_bit(NFS_LSEG_VALID, &lseg->pls_flags));

		list_del(&lseg->pls_list);

	list_del_init(&lseg->pls_list);

	if (list_empty(&lseg->pls_layout->plh_segs)) {

		set_bit(NFS_LAYOUT_DESTROYED, &lseg->pls_layout->plh_flags);

		/* Matched by initial refcount set in alloc_init_layout_hdr */

		put_layout_hdr_locked(lseg->pls_layout);

	}

		rpc_wake_up(&NFS_SERVER(ino)->roc_rpcwaitq);

		list_add(&lseg->pls_list, tmp_list);

		return 1;

	rpc_wake_up(&NFS_SERVER(inode)->roc_rpcwaitq);

}



static void

put_lseg(struct pnfs_layout_segment *lseg)

{

	struct inode *inode;



	if (!lseg)

		return;



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

		atomic_read(&lseg->pls_refcount),

		test_bit(NFS_LSEG_VALID, &lseg->pls_flags));

	inode = lseg->pls_layout->plh_inode;

	if (atomic_dec_and_lock(&lseg->pls_refcount, &inode->i_lock)) {

		LIST_HEAD(free_me);



		put_lseg_common(lseg);

		list_add(&lseg->pls_list, &free_me);

		spin_unlock(&inode->i_lock);

		pnfs_free_lseg_list(&free_me);

	}

	return 0;

}



static bool
@@ -276,7 +285,13 @@ static int mark_lseg_invalid(struct pnfs_layout_segment *lseg, 
		 * list.  It will now be removed when all

		 * outstanding io is finished.

		 */

		rv = put_lseg_locked(lseg, tmp_list);

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

			atomic_read(&lseg->pls_refcount));

		if (atomic_dec_and_test(&lseg->pls_refcount)) {

			put_lseg_common(lseg);

			list_add(&lseg->pls_list, tmp_list);

			rv = 1;

		}

	}

	return rv;

}
@@ -689,7 +704,7 @@ pnfs_find_lseg(struct pnfs_layout_hdr *lo, u32 iomode) 
	list_for_each_entry(lseg, &lo->plh_segs, pls_list) {

		if (test_bit(NFS_LSEG_VALID, &lseg->pls_flags) &&

		    is_matching_lseg(lseg, iomode)) {

			ret = lseg;

			ret = get_lseg(lseg);

			break;

		}

		if (cmp_layout(iomode, lseg->pls_range.iomode) > 0)
@@ -769,6 +784,7 @@ pnfs_update_layout(struct inode *ino, 
out:

	dprintk("%s end, state 0x%lx lseg %p\n", __func__,

		nfsi->layout ? nfsi->layout->plh_flags : -1, lseg);

	put_lseg(lseg); /* STUB - callers currently ignore return value */

	return lseg;

out_unlock:

	spin_unlock(&ino->i_lock);
@@ -821,7 +837,7 @@ pnfs_layout_process(struct nfs4_layoutget *lgp) 
	}

	init_lseg(lo, lseg);

	lseg->pls_range = res->range;

	*lgp->lsegpp = lseg;

	*lgp->lsegpp = get_lseg(lseg);

	pnfs_insert_layout(lo, lseg);



	if (res->return_on_close) {

fs/nfs/pnfs.h

+20 −0
Original line number Diff line number Diff line
@@ -177,6 +177,16 @@ static inline int lo_fail_bit(u32 iomode) 
			 NFS_LAYOUT_RW_FAILED : NFS_LAYOUT_RO_FAILED;

}



static inline struct pnfs_layout_segment *

get_lseg(struct pnfs_layout_segment *lseg)

{

	if (lseg) {

		atomic_inc(&lseg->pls_refcount);

		smp_mb__after_atomic_inc();

	}

	return lseg;

}



/* Return true if a layout driver is being used for this mountpoint */

static inline int pnfs_enabled_sb(struct nfs_server *nfss)

{
@@ -193,6 +203,16 @@ static inline void pnfs_destroy_layout(struct nfs_inode *nfsi) 
{

}



static inline struct pnfs_layout_segment *

get_lseg(struct pnfs_layout_segment *lseg)

{

	return NULL;

}



static inline void put_lseg(struct pnfs_layout_segment *lseg)

{

}



static inline struct pnfs_layout_segment *

pnfs_update_layout(struct inode *ino, struct nfs_open_context *ctx,

		   enum pnfs_iomode access_type)