On Thu, May 27, 2021 at 08:47:16AM +1000, Dave Chinner wrote:
> From: Dave Chinner <dchinner@xxxxxxxxxx>
>
> Only called from one place now, so merge it into
> xfs_buf_alloc_pages(). Because page array allocation is dependent on
> bp->b_pages being null, always ensure that when the pages array is
> freed we always set bp->b_pages to null.
>
> Also convert the page array to use kmalloc() rather than
> kmem_alloc() so we can use the gfp flags we've already calculated
> for the allocation context instead of hard coding KM_NOFS semantics.
>
> Signed-off-by: Dave Chinner <dchinner@xxxxxxxxxx>
Yippeeeee
Reviewed-by: Darrick J. Wong <djwong@xxxxxxxxxx>
--D
> ---
> fs/xfs/xfs_buf.c | 48 ++++++++++++++----------------------------------
> 1 file changed, 14 insertions(+), 34 deletions(-)
>
> diff --git a/fs/xfs/xfs_buf.c b/fs/xfs/xfs_buf.c
> index 8ca4add138c5..aa978111c01f 100644
> --- a/fs/xfs/xfs_buf.c
> +++ b/fs/xfs/xfs_buf.c
> @@ -272,31 +272,6 @@ _xfs_buf_alloc(
> return 0;
> }
>
> -/*
> - * Allocate a page array capable of holding a specified number
> - * of pages, and point the page buf at it.
> - */
> -STATIC int
> -_xfs_buf_get_pages(
> - struct xfs_buf *bp,
> - int page_count)
> -{
> - /* Make sure that we have a page list */
> - if (bp->b_pages == NULL) {
> - bp->b_page_count = page_count;
> - if (page_count <= XB_PAGES) {
> - bp->b_pages = bp->b_page_array;
> - } else {
> - bp->b_pages = kmem_alloc(sizeof(struct page *) *
> - page_count, KM_NOFS);
> - if (bp->b_pages == NULL)
> - return -ENOMEM;
> - }
> - memset(bp->b_pages, 0, sizeof(struct page *) * page_count);
> - }
> - return 0;
> -}
> -
> /*
> * Frees b_pages if it was allocated.
> */
> @@ -304,10 +279,9 @@ STATIC void
> _xfs_buf_free_pages(
> struct xfs_buf *bp)
> {
> - if (bp->b_pages != bp->b_page_array) {
> + if (bp->b_pages != bp->b_page_array)
> kmem_free(bp->b_pages);
> - bp->b_pages = NULL;
> - }
> + bp->b_pages = NULL;
> }
>
> /*
> @@ -389,16 +363,22 @@ xfs_buf_alloc_pages(
> long filled = 0;
> int error;
>
> + /* Make sure that we have a page list */
> + bp->b_page_count = page_count;
> + if (bp->b_page_count <= XB_PAGES) {
> + bp->b_pages = bp->b_page_array;
> + } else {
> + bp->b_pages = kzalloc(sizeof(struct page *) * bp->b_page_count,
> + gfp_mask);
> + if (!bp->b_pages)
> + return -ENOMEM;
> + }
> + bp->b_flags |= _XBF_PAGES;
> +
> /* Assure zeroed buffer for non-read cases. */
> if (!(flags & XBF_READ))
> gfp_mask |= __GFP_ZERO;
>
> - error = _xfs_buf_get_pages(bp, page_count);
> - if (unlikely(error))
> - return error;
> -
> - bp->b_flags |= _XBF_PAGES;
> -
> /*
> * Bulk filling of pages can take multiple calls. Not filling the entire
> * array is not an allocation failure, so don't back off if we get at
> --
> 2.31.1
>
