Re: [PATCH v4 05/27] pnfs: let layoutcommit handle a list of lseg

[Boaz Harrosh <bharrosh@panasas.com>]

On 07/28/2011 10:30 AM, Jim Rees wrote:
> From: Peng Tao <bergwolf@gmail.com>
> 
> There can be multiple lseg per file, so layoutcommit should be
> able to handle it.
> 

Thanks Peng, Jim

Trond

I think this patch and the next one should be the minimal set
that I need for Stable.

Let me test Vanila 3.0 and I'll come back to you

Thanks
Boaz

> Signed-off-by: Peng Tao <peng_tao@emc.com>

> ---
>  fs/nfs/nfs4proc.c       |    8 +++++++-
>  fs/nfs/pnfs.c           |   34 +++++++++++++++++-----------------
>  fs/nfs/pnfs.h           |    2 ++
>  include/linux/nfs_xdr.h |    2 +-
>  4 files changed, 27 insertions(+), 19 deletions(-)
> 
> diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
> index ebb6f1a..af32d3d 100644
> --- a/fs/nfs/nfs4proc.c
> +++ b/fs/nfs/nfs4proc.c
> @@ -5960,9 +5960,15 @@ nfs4_layoutcommit_done(struct rpc_task *task, void *calldata)
>  static void nfs4_layoutcommit_release(void *calldata)
>  {
>  	struct nfs4_layoutcommit_data *data = calldata;
> +	struct pnfs_layout_segment *lseg, *tmp;
>  
>  	/* Matched by references in pnfs_set_layoutcommit */
> -	put_lseg(data->lseg);
> +	list_for_each_entry_safe(lseg, tmp, &data->lseg_list, pls_lc_list) {
> +		list_del_init(&lseg->pls_lc_list);
> +		if (test_and_clear_bit(NFS_LSEG_LAYOUTCOMMIT,
> +				       &lseg->pls_flags))
> +			put_lseg(lseg);
> +	}
>  	put_rpccred(data->cred);
>  	kfree(data);
>  }
> diff --git a/fs/nfs/pnfs.c b/fs/nfs/pnfs.c
> index 201165e..e2c1eb4 100644
> --- a/fs/nfs/pnfs.c
> +++ b/fs/nfs/pnfs.c
> @@ -235,6 +235,7 @@ static void
>  init_lseg(struct pnfs_layout_hdr *lo, struct pnfs_layout_segment *lseg)
>  {
>  	INIT_LIST_HEAD(&lseg->pls_list);
> +	INIT_LIST_HEAD(&lseg->pls_lc_list);
>  	atomic_set(&lseg->pls_refcount, 1);
>  	smp_mb();
>  	set_bit(NFS_LSEG_VALID, &lseg->pls_flags);
> @@ -1361,16 +1362,17 @@ pnfs_generic_pg_readpages(struct nfs_pageio_descriptor *desc)
>  EXPORT_SYMBOL_GPL(pnfs_generic_pg_readpages);
>  
>  /*
> - * Currently there is only one (whole file) write lseg.
> + * There can be multiple RW segments.
>   */
> -static struct pnfs_layout_segment *pnfs_list_write_lseg(struct inode *inode)
> +static void pnfs_list_write_lseg(struct inode *inode, struct list_head *listp)
>  {
> -	struct pnfs_layout_segment *lseg, *rv = NULL;
> +	struct pnfs_layout_segment *lseg;
>  
> -	list_for_each_entry(lseg, &NFS_I(inode)->layout->plh_segs, pls_list)
> -		if (lseg->pls_range.iomode == IOMODE_RW)
> -			rv = lseg;
> -	return rv;
> +	list_for_each_entry(lseg, &NFS_I(inode)->layout->plh_segs, pls_list) {
> +		if (lseg->pls_range.iomode == IOMODE_RW &&
> +		    test_bit(NFS_LSEG_LAYOUTCOMMIT, &lseg->pls_flags))
> +			list_add(&lseg->pls_lc_list, listp);
> +	}
>  }
>  
>  void
> @@ -1382,14 +1384,16 @@ pnfs_set_layoutcommit(struct nfs_write_data *wdata)
>  
>  	spin_lock(&nfsi->vfs_inode.i_lock);
>  	if (!test_and_set_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags)) {
> -		/* references matched in nfs4_layoutcommit_release */
> -		get_lseg(wdata->lseg);
> +		mark_as_dirty = true;
>  		nfsi->layout->plh_lc_cred =
>  			get_rpccred(wdata->args.context->state->owner->so_cred);
> -		mark_as_dirty = true;
>  		dprintk("%s: Set layoutcommit for inode %lu ",
>  			__func__, wdata->inode->i_ino);
>  	}
> +	if (!test_and_set_bit(NFS_LSEG_LAYOUTCOMMIT, &wdata->lseg->pls_flags)) {
> +		/* references matched in nfs4_layoutcommit_release */
> +		get_lseg(wdata->lseg);
> +	}
>  	if (end_pos > nfsi->layout->plh_lwb)
>  		nfsi->layout->plh_lwb = end_pos;
>  	spin_unlock(&nfsi->vfs_inode.i_lock);
> @@ -1416,7 +1420,6 @@ pnfs_layoutcommit_inode(struct inode *inode, bool sync)
>  {
>  	struct nfs4_layoutcommit_data *data;
>  	struct nfs_inode *nfsi = NFS_I(inode);
> -	struct pnfs_layout_segment *lseg;
>  	struct rpc_cred *cred;
>  	loff_t end_pos;
>  	int status = 0;
> @@ -1434,17 +1437,15 @@ pnfs_layoutcommit_inode(struct inode *inode, bool sync)
>  		goto out;
>  	}
>  
> +	INIT_LIST_HEAD(&data->lseg_list);
>  	spin_lock(&inode->i_lock);
>  	if (!test_and_clear_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags)) {
>  		spin_unlock(&inode->i_lock);
>  		kfree(data);
>  		goto out;
>  	}
> -	/*
> -	 * Currently only one (whole file) write lseg which is referenced
> -	 * in pnfs_set_layoutcommit and will be found.
> -	 */
> -	lseg = pnfs_list_write_lseg(inode);
> +
> +	pnfs_list_write_lseg(inode, &data->lseg_list);
>  
>  	end_pos = nfsi->layout->plh_lwb;
>  	cred = nfsi->layout->plh_lc_cred;
> @@ -1456,7 +1457,6 @@ pnfs_layoutcommit_inode(struct inode *inode, bool sync)
>  	spin_unlock(&inode->i_lock);
>  
>  	data->args.inode = inode;
> -	data->lseg = lseg;
>  	data->cred = cred;
>  	nfs_fattr_init(&data->fattr);
>  	data->args.bitmask = NFS_SERVER(inode)->cache_consistency_bitmask;
> diff --git a/fs/nfs/pnfs.h b/fs/nfs/pnfs.h
> index ac86c36..bddd8b9 100644
> --- a/fs/nfs/pnfs.h
> +++ b/fs/nfs/pnfs.h
> @@ -36,10 +36,12 @@
>  enum {
>  	NFS_LSEG_VALID = 0,	/* cleared when lseg is recalled/returned */
>  	NFS_LSEG_ROC,		/* roc bit received from server */
> +	NFS_LSEG_LAYOUTCOMMIT,	/* layoutcommit bit set for layoutcommit */
>  };
>  
>  struct pnfs_layout_segment {
>  	struct list_head pls_list;
> +	struct list_head pls_lc_list;
>  	struct pnfs_layout_range pls_range;
>  	atomic_t pls_refcount;
>  	unsigned long pls_flags;
> diff --git a/include/linux/nfs_xdr.h b/include/linux/nfs_xdr.h
> index a07b682..21f333e 100644
> --- a/include/linux/nfs_xdr.h
> +++ b/include/linux/nfs_xdr.h
> @@ -273,7 +273,7 @@ struct nfs4_layoutcommit_res {
>  struct nfs4_layoutcommit_data {
>  	struct rpc_task task;
>  	struct nfs_fattr fattr;
> -	struct pnfs_layout_segment *lseg;
> +	struct list_head lseg_list;
>  	struct rpc_cred *cred;
>  	struct nfs4_layoutcommit_args args;
>  	struct nfs4_layoutcommit_res res;