Commit 9beae1ea authored by Lorenzo Stoakes's avatar Lorenzo Stoakes Committed by Linus Torvalds
Browse files

mm: replace get_user_pages_remote() write/force parameters with gup_flags 



This removes the 'write' and 'force' from get_user_pages_remote() and
replaces them with 'gup_flags' to make the use of FOLL_FORCE explicit in
callers as use of this flag can result in surprising behaviour (and
hence bugs) within the mm subsystem.

Signed-off-by: default avatarLorenzo Stoakes <lstoakes@gmail.com>
Acked-by: default avatarMichal Hocko <mhocko@suse.com>
Reviewed-by: default avatarJan Kara <jack@suse.cz>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 768ae309

drivers/gpu/drm/etnaviv/etnaviv_gem.c

+5 −2
Original line number Original line Diff line number Diff line
@@ -748,19 +748,22 @@ static struct page **etnaviv_gem_userptr_do_get_pages( 
	int ret = 0, pinned, npages = etnaviv_obj->base.size >> PAGE_SHIFT;

	int ret = 0, pinned, npages = etnaviv_obj->base.size >> PAGE_SHIFT;

	struct page **pvec;

	struct page **pvec;

	uintptr_t ptr;

	uintptr_t ptr;

	unsigned int flags = 0;





	pvec = drm_malloc_ab(npages, sizeof(struct page *));

	pvec = drm_malloc_ab(npages, sizeof(struct page *));

	if (!pvec)

	if (!pvec)

		return ERR_PTR(-ENOMEM);

		return ERR_PTR(-ENOMEM);





	if (!etnaviv_obj->userptr.ro)

		flags |= FOLL_WRITE;



	pinned = 0;

	pinned = 0;

	ptr = etnaviv_obj->userptr.ptr;

	ptr = etnaviv_obj->userptr.ptr;





	down_read(&mm->mmap_sem);

	down_read(&mm->mmap_sem);

	while (pinned < npages) {

	while (pinned < npages) {

		ret = get_user_pages_remote(task, mm, ptr, npages - pinned,

		ret = get_user_pages_remote(task, mm, ptr, npages - pinned,

					    !etnaviv_obj->userptr.ro, 0,

					    flags, pvec + pinned, NULL);

					    pvec + pinned, NULL);

		if (ret < 0)

		if (ret < 0)

			break;

			break;

drivers/gpu/drm/i915/i915_gem_userptr.c

+5 −1
Original line number Original line Diff line number Diff line
@@ -508,6 +508,10 @@ __i915_gem_userptr_get_pages_worker(struct work_struct *_work) 
	pvec = drm_malloc_gfp(npages, sizeof(struct page *), GFP_TEMPORARY);

	pvec = drm_malloc_gfp(npages, sizeof(struct page *), GFP_TEMPORARY);

	if (pvec != NULL) {

	if (pvec != NULL) {

		struct mm_struct *mm = obj->userptr.mm->mm;

		struct mm_struct *mm = obj->userptr.mm->mm;

		unsigned int flags = 0;



		if (!obj->userptr.read_only)

			flags |= FOLL_WRITE;





		ret = -EFAULT;

		ret = -EFAULT;

		if (atomic_inc_not_zero(&mm->mm_users)) {

		if (atomic_inc_not_zero(&mm->mm_users)) {
@@ -517,7 +521,7 @@ __i915_gem_userptr_get_pages_worker(struct work_struct *_work) 
					(work->task, mm,

					(work->task, mm,

					 obj->userptr.ptr + pinned * PAGE_SIZE,

					 obj->userptr.ptr + pinned * PAGE_SIZE,

					 npages - pinned,

					 npages - pinned,

					 !obj->userptr.read_only, 0,

					 flags,

					 pvec + pinned, NULL);

					 pvec + pinned, NULL);

				if (ret < 0)

				if (ret < 0)

					break;

					break;

drivers/infiniband/core/umem_odp.c

+5 −2
Original line number Original line Diff line number Diff line
@@ -527,6 +527,7 @@ int ib_umem_odp_map_dma_pages(struct ib_umem *umem, u64 user_virt, u64 bcnt, 
	u64 off;

	u64 off;

	int j, k, ret = 0, start_idx, npages = 0;

	int j, k, ret = 0, start_idx, npages = 0;

	u64 base_virt_addr;

	u64 base_virt_addr;

	unsigned int flags = 0;





	if (access_mask == 0)

	if (access_mask == 0)

		return -EINVAL;

		return -EINVAL;
@@ -556,6 +557,9 @@ int ib_umem_odp_map_dma_pages(struct ib_umem *umem, u64 user_virt, u64 bcnt, 
		goto out_put_task;

		goto out_put_task;

	}

	}





	if (access_mask & ODP_WRITE_ALLOWED_BIT)

		flags |= FOLL_WRITE;



	start_idx = (user_virt - ib_umem_start(umem)) >> PAGE_SHIFT;

	start_idx = (user_virt - ib_umem_start(umem)) >> PAGE_SHIFT;

	k = start_idx;

	k = start_idx;
@@ -574,8 +578,7 @@ int ib_umem_odp_map_dma_pages(struct ib_umem *umem, u64 user_virt, u64 bcnt, 
		 */

		 */

		npages = get_user_pages_remote(owning_process, owning_mm,

		npages = get_user_pages_remote(owning_process, owning_mm,

				user_virt, gup_num_pages,

				user_virt, gup_num_pages,

				access_mask & ODP_WRITE_ALLOWED_BIT,

				flags, local_page_list, NULL);

				0, local_page_list, NULL);

		up_read(&owning_mm->mmap_sem);

		up_read(&owning_mm->mmap_sem);





		if (npages < 0)

		if (npages < 0)

fs/exec.c

+7 −2
Original line number Original line Diff line number Diff line
@@ -191,6 +191,7 @@ static struct page *get_arg_page(struct linux_binprm *bprm, unsigned long pos, 
{

{

	struct page *page;

	struct page *page;

	int ret;

	int ret;

	unsigned int gup_flags = FOLL_FORCE;





#ifdef CONFIG_STACK_GROWSUP

#ifdef CONFIG_STACK_GROWSUP

	if (write) {

	if (write) {
@@ -199,12 +200,16 @@ static struct page *get_arg_page(struct linux_binprm *bprm, unsigned long pos, 
			return NULL;

			return NULL;

	}

	}

#endif

#endif



	if (write)

		gup_flags |= FOLL_WRITE;



	/*

	/*

	 * We are doing an exec().  'current' is the process

	 * We are doing an exec().  'current' is the process

	 * doing the exec and bprm->mm is the new process's mm.

	 * doing the exec and bprm->mm is the new process's mm.

	 */

	 */

	ret = get_user_pages_remote(current, bprm->mm, pos, 1, write,

	ret = get_user_pages_remote(current, bprm->mm, pos, 1, gup_flags,

			1, &page, NULL);

			&page, NULL);

	if (ret <= 0)

	if (ret <= 0)

		return NULL;

		return NULL;

include/linux/mm.h

+1 −1
Original line number Original line Diff line number Diff line
@@ -1276,7 +1276,7 @@ long __get_user_pages(struct task_struct *tsk, struct mm_struct *mm, 
		      struct vm_area_struct **vmas, int *nonblocking);

		      struct vm_area_struct **vmas, int *nonblocking);

long get_user_pages_remote(struct task_struct *tsk, struct mm_struct *mm,

long get_user_pages_remote(struct task_struct *tsk, struct mm_struct *mm,

			    unsigned long start, unsigned long nr_pages,

			    unsigned long start, unsigned long nr_pages,

			    int write, int force, struct page **pages,

			    unsigned int gup_flags, struct page **pages,

			    struct vm_area_struct **vmas);

			    struct vm_area_struct **vmas);

long get_user_pages(unsigned long start, unsigned long nr_pages,

long get_user_pages(unsigned long start, unsigned long nr_pages,

			    unsigned int gup_flags, struct page **pages,

			    unsigned int gup_flags, struct page **pages,