Re: [PATCH 3/7] ecryptfs: use ZERO_PAGE instead of allocating zeroed memory in truncate_upper

Tyler Hicks <[email protected]> Mon, 6 Apr 2026 00:52:51 -0500
Newsgroups org.kernel.vger.ecryptfs,org.kernel.vger.linux-fsdevel
Message-ID <adNKM-8zHwrR6AbI@yaupon>
On 2026-03-31 17:37:24, Christoph Hellwig wrote:
> Use the existing pre-zeroed memory instead of allocating a new chunk.
> 
> Signed-off-by: Christoph Hellwig <[email protected]>

Nice improvement!

Tyler

> ---
>  fs/ecryptfs/inode.c | 11 ++---------
>  1 file changed, 2 insertions(+), 9 deletions(-)
> 
> diff --git a/fs/ecryptfs/inode.c b/fs/ecryptfs/inode.c
> index 46dc867a8860..57df35a22e9c 100644
> --- a/fs/ecryptfs/inode.c
> +++ b/fs/ecryptfs/inode.c
> @@ -771,15 +771,8 @@ static int truncate_upper(struct dentry *dentry, struct iattr *ia,
>  	 */
>  	num_zeros = PAGE_SIZE - (ia->ia_size & ~PAGE_MASK);
>  	if (num_zeros) {
> -		char *zeros_virt;
> -
> -		zeros_virt = kzalloc(num_zeros, GFP_KERNEL);
> -		if (!zeros_virt) {
> -			rc = -ENOMEM;
> -			goto out;
> -		}
> -		rc = ecryptfs_write(inode, zeros_virt, ia->ia_size, num_zeros);
> -		kfree(zeros_virt);
> +		rc = ecryptfs_write(inode, page_address(ZERO_PAGE(0)),
> +				ia->ia_size, num_zeros);
>  		if (rc) {
>  			pr_err("Error attempting to zero out the remainder of the end page on reducing truncate; rc = [%d]\n",
>  				rc);
> -- 
> 2.47.3
>