Re: [PATCH 06/14] staging/lustre/llite: drop_caches hangs in cl_inode_fini()

[James Simmons <jsimmons@infradead.org>]

> From: Andrew Perepechko <andrew.perepechko@seagate.com>
> 
> This patch releases cl_pages on error in ll_write_begin()
> to avoid memory and object reference leaks. Also, it
> reuses per-cpu lu_env in ll_invalidatepage() in the same
> way as done in ll_releasepage().

Reviewed-by: James Simmons <jsimmons@infradead.org>
 
> Signed-off-by: Andrew Perepechko <andrew.perepechko@seagate.com>
> Seagate-bug-id: MRP-3504
> Reviewed-on: http://review.whamcloud.com/22745
> Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-8509
> Reviewed-by: Jinshan Xiong <jinshan.xiong@intel.com>
> Reviewed-by: Bobi Jam <bobijam@hotmail.com>
> Signed-off-by: Oleg Drokin <green@linuxhacker.ru>
> ---
>  drivers/staging/lustre/lustre/llite/rw26.c | 36 ++++++++++++++++--------------
>  1 file changed, 19 insertions(+), 17 deletions(-)
> 
> diff --git a/drivers/staging/lustre/lustre/llite/rw26.c b/drivers/staging/lustre/lustre/llite/rw26.c
> index 1a08a9d..ca45b44 100644
> --- a/drivers/staging/lustre/lustre/llite/rw26.c
> +++ b/drivers/staging/lustre/lustre/llite/rw26.c
> @@ -71,8 +71,6 @@ static void ll_invalidatepage(struct page *vmpage, unsigned int offset,
>  	struct cl_page   *page;
>  	struct cl_object *obj;
>  
> -	int refcheck;
> -
>  	LASSERT(PageLocked(vmpage));
>  	LASSERT(!PageWriteback(vmpage));
>  
> @@ -82,21 +80,21 @@ static void ll_invalidatepage(struct page *vmpage, unsigned int offset,
>  	 * happening with locked page too
>  	 */
>  	if (offset == 0 && length == PAGE_SIZE) {
> -		env = cl_env_get(&refcheck);
> -		if (!IS_ERR(env)) {
> -			inode = vmpage->mapping->host;
> -			obj = ll_i2info(inode)->lli_clob;
> -			if (obj) {
> -				page = cl_vmpage_page(vmpage, obj);
> -				if (page) {
> -					cl_page_delete(env, page);
> -					cl_page_put(env, page);
> -				}
> -			} else {
> -				LASSERT(vmpage->private == 0);
> +		/* See the comment in ll_releasepage() */
> +		env = cl_env_percpu_get();
> +		LASSERT(!IS_ERR(env));
> +		inode = vmpage->mapping->host;
> +		obj = ll_i2info(inode)->lli_clob;
> +		if (obj) {
> +			page = cl_vmpage_page(vmpage, obj);
> +			if (page) {
> +				cl_page_delete(env, page);
> +				cl_page_put(env, page);
>  			}
> -			cl_env_put(env, &refcheck);
> +		} else {
> +			LASSERT(vmpage->private == 0);
>  		}
> +		cl_env_percpu_put(env);
>  	}
>  }
>  
> @@ -466,9 +464,9 @@ static int ll_write_begin(struct file *file, struct address_space *mapping,
>  			  struct page **pagep, void **fsdata)
>  {
>  	struct ll_cl_context *lcc;
> -	const struct lu_env  *env;
> +	const struct lu_env *env = NULL;
>  	struct cl_io   *io;
> -	struct cl_page *page;
> +	struct cl_page *page = NULL;
>  	struct cl_object *clob = ll_i2info(mapping->host)->lli_clob;
>  	pgoff_t index = pos >> PAGE_SHIFT;
>  	struct page *vmpage = NULL;
> @@ -556,6 +554,10 @@ static int ll_write_begin(struct file *file, struct address_space *mapping,
>  			unlock_page(vmpage);
>  			put_page(vmpage);
>  		}
> +		if (!IS_ERR_OR_NULL(page)) {
> +			lu_ref_del(&page->cp_reference, "cl_io", io);
> +			cl_page_put(env, page);
> +		}
>  	} else {
>  		*pagep = vmpage;
>  		*fsdata = lcc;
> -- 
> 2.7.4
> 
>