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Commit 79a48a1f authored by Weston Andros Adamson's avatar Weston Andros Adamson Committed by Trond Myklebust
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Don't mark_inode_dirty_sync() while holding lock 



mark_inode_dirty_sync() grabs the same inode lock!

race conditions between holding the lock in pnfs_set_layoutcommit() and in
mark_inode_dirty_sync() can result in a second call to pnfs_layoutcommit_inode(), but
this will be a noop as NFS_INO_LAYOUTCOMMIT won't be set in the second call

Signed-off-by: default avatarWeston Andros Adamson <dros@netapp.com>
Signed-off-by: default avatarTrond Myklebust <Trond.Myklebust@netapp.com>
parent c0d0e96b

fs/nfs/pnfs.c

+7 −1
Original line number Original line Diff line number Diff line
@@ -1004,6 +1004,7 @@ pnfs_set_layoutcommit(struct nfs_write_data *wdata) 
{

{

	struct nfs_inode *nfsi = NFS_I(wdata->inode);

	struct nfs_inode *nfsi = NFS_I(wdata->inode);

	loff_t end_pos = wdata->args.offset + wdata->res.count;

	loff_t end_pos = wdata->args.offset + wdata->res.count;

	bool mark_as_dirty = false;





	spin_lock(&nfsi->vfs_inode.i_lock);

	spin_lock(&nfsi->vfs_inode.i_lock);

	if (!test_and_set_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags)) {

	if (!test_and_set_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags)) {
@@ -1011,13 +1012,18 @@ pnfs_set_layoutcommit(struct nfs_write_data *wdata) 
		get_lseg(wdata->lseg);

		get_lseg(wdata->lseg);

		wdata->lseg->pls_lc_cred =

		wdata->lseg->pls_lc_cred =

			get_rpccred(wdata->args.context->state->owner->so_cred);

			get_rpccred(wdata->args.context->state->owner->so_cred);

		mark_inode_dirty_sync(wdata->inode);

		mark_as_dirty = true;

		dprintk("%s: Set layoutcommit for inode %lu ",

		dprintk("%s: Set layoutcommit for inode %lu ",

			__func__, wdata->inode->i_ino);

			__func__, wdata->inode->i_ino);

	}

	}

	if (end_pos > wdata->lseg->pls_end_pos)

	if (end_pos > wdata->lseg->pls_end_pos)

		wdata->lseg->pls_end_pos = end_pos;

		wdata->lseg->pls_end_pos = end_pos;

	spin_unlock(&nfsi->vfs_inode.i_lock);

	spin_unlock(&nfsi->vfs_inode.i_lock);



	/* if pnfs_layoutcommit_inode() runs between inode locks, the next one

	 * will be a noop because NFS_INO_LAYOUTCOMMIT will not be set */

	if (mark_as_dirty)

		mark_inode_dirty_sync(wdata->inode);

}

}

EXPORT_SYMBOL_GPL(pnfs_set_layoutcommit);

EXPORT_SYMBOL_GPL(pnfs_set_layoutcommit);