On Thu, Jul 04, 2024 at 02:27:14PM GMT, Liam R. Howlett wrote:
> From: "Liam R. Howlett" <Liam.Howlett@xxxxxxxxxx>
>
> With the only caller to unmap_region() being the error path of
> mmap_region(), the argument list can be significantly reduced.
>
> There is also no need to forward declare the static function any
> longer.
>
> Signed-off-by: Liam R. Howlett <Liam.Howlett@xxxxxxxxxx>
> ---
> mm/mmap.c | 25 +++++++++----------------
> 1 file changed, 9 insertions(+), 16 deletions(-)
>
> diff --git a/mm/mmap.c b/mm/mmap.c
> index 45443a53be76..5d458c5f080e 100644
> --- a/mm/mmap.c
> +++ b/mm/mmap.c
> @@ -76,11 +76,6 @@ int mmap_rnd_compat_bits __read_mostly = CONFIG_ARCH_MMAP_RND_COMPAT_BITS;
> static bool ignore_rlimit_data;
> core_param(ignore_rlimit_data, ignore_rlimit_data, bool, 0644);
>
> -static void unmap_region(struct mm_struct *mm, struct ma_state *mas,
> - struct vm_area_struct *vma, struct vm_area_struct *prev,
> - struct vm_area_struct *next, unsigned long start,
> - unsigned long end, unsigned long tree_end, bool mm_wr_locked);
> -
> static pgprot_t vm_pgprot_modify(pgprot_t oldprot, unsigned long vm_flags)
> {
> return pgprot_modify(oldprot, vm_get_page_prot(vm_flags));
> @@ -2398,22 +2393,21 @@ struct vm_area_struct *expand_stack(struct mm_struct *mm, unsigned long addr)
> *
> * Called with the mm semaphore held.
> */
> -static void unmap_region(struct mm_struct *mm, struct ma_state *mas,
> - struct vm_area_struct *vma, struct vm_area_struct *prev,
> - struct vm_area_struct *next, unsigned long start,
> - unsigned long end, unsigned long tree_end, bool mm_wr_locked)
> +static void unmap_region(struct ma_state *mas, struct vm_area_struct *vma,
> + struct vm_area_struct *prev, struct vm_area_struct *next)
> {
> + struct mm_struct *mm = vma->vm_mm;
> struct mmu_gather tlb;
> - unsigned long mt_start = mas->index;
>
> lru_add_drain();
> tlb_gather_mmu(&tlb, mm);
> update_hiwater_rss(mm);
> - unmap_vmas(&tlb, mas, vma, start, end, tree_end, mm_wr_locked);
> - mas_set(mas, mt_start);
OK so the 'raise something in one patch only for it to be removed in the
next' pattern continues :) more aesthetically plasing.
> + unmap_vmas(&tlb, mas, vma, vma->vm_start, vma->vm_end, vma->vm_end,
> + /* mm_wr_locked = */ true);
> + mas_set(mas, vma->vm_end);
> free_pgtables(&tlb, mas, vma, prev ? prev->vm_end : FIRST_USER_ADDRESS,
> - next ? next->vm_start : USER_PGTABLES_CEILING,
> - mm_wr_locked);
> + next ? next->vm_start : USER_PGTABLES_CEILING,
> + /* mm_wr_locked = */ true);
> tlb_finish_mmu(&tlb);
> }
>
> @@ -3186,8 +3180,7 @@ unsigned long mmap_region(struct file *file, unsigned long addr,
>
> vma_iter_set(&vmi, vma->vm_end);
> /* Undo any partial mapping done by a device driver. */
> - unmap_region(mm, &vmi.mas, vma, prev, next, vma->vm_start,
> - vma->vm_end, vma->vm_end, true);
> + unmap_region(&vmi.mas, vma, prev, next);
> }
> if (writable_file_mapping)
> mapping_unmap_writable(file->f_mapping);
> --
> 2.43.0
>
Lovely reduction in parameters.
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@xxxxxxxxxx>
