Commit 5972d97c authored by Liam R. Howlett's avatar Liam R. Howlett Committed by Andrew Morton
Browse files

mm/mmap: use PHYS_PFN in mmap_region() 

Instead of shifting the length by PAGE_SIZE, use PHYS_PFN.  Also use the
existing local variable everywhere instead of some of the time.

Link: https://lkml.kernel.org/r/20240830040101.822209-17-Liam.Howlett@oracle.com


Signed-off-by: default avatarLiam R. Howlett <Liam.Howlett@Oracle.com>
Reviewed-by: default avatarLorenzo Stoakes <lorenzo.stoakes@oracle.com>
Reviewed-by: default avatarSuren Baghdasaryan <surenb@google.com>
Cc: Bert Karwatzki <spasswolf@web.de>
Cc: Jeff Xu <jeffxu@chromium.org>
Cc: Jiri Olsa <olsajiri@gmail.com>
Cc: Kees Cook <kees@kernel.org>
Cc: Lorenzo Stoakes <lstoakes@gmail.com>
Cc: Mark Brown <broonie@kernel.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: "Paul E. McKenney" <paulmck@kernel.org>
Cc: Paul Moore <paul@paul-moore.com>
Cc: Sidhartha Kumar <sidhartha.kumar@oracle.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent 4f87153e

mm/mmap.c

+5 −5
Original line number Diff line number Diff line
@@ -1364,7 +1364,7 @@ unsigned long mmap_region(struct file *file, unsigned long addr, 
	struct mm_struct *mm = current->mm;

	struct vm_area_struct *vma = NULL;

	struct vm_area_struct *next, *prev, *merge;

	pgoff_t pglen = len >> PAGE_SHIFT;

	pgoff_t pglen = PHYS_PFN(len);

	unsigned long charged = 0;

	struct vma_munmap_struct vms;

	struct ma_state mas_detach;
@@ -1384,7 +1384,7 @@ unsigned long mmap_region(struct file *file, unsigned long addr, 
	 * MAP_FIXED may remove pages of mappings that intersects with requested

	 * mapping. Account for the pages it would unmap.

	 */

	if (!may_expand_vm(mm, vm_flags, (len >> PAGE_SHIFT) - nr_pages))

	if (!may_expand_vm(mm, vm_flags, pglen - nr_pages))

		return -ENOMEM;



	/* Find the first overlapping VMA */
@@ -1413,7 +1413,7 @@ unsigned long mmap_region(struct file *file, unsigned long addr, 
	 * Private writable mapping: check memory availability

	 */

	if (accountable_mapping(file, vm_flags)) {

		charged = len >> PAGE_SHIFT;

		charged = pglen;

		charged -= nr_accounted;

		if (security_vm_enough_memory_mm(mm, charged))

			goto abort_munmap;
@@ -1574,14 +1574,14 @@ unsigned long mmap_region(struct file *file, unsigned long addr, 
	/* Unmap any existing mapping in the area */

	vms_complete_munmap_vmas(&vms, &mas_detach);



	vm_stat_account(mm, vm_flags, len >> PAGE_SHIFT);

	vm_stat_account(mm, vm_flags, pglen);

	if (vm_flags & VM_LOCKED) {

		if ((vm_flags & VM_SPECIAL) || vma_is_dax(vma) ||

					is_vm_hugetlb_page(vma) ||

					vma == get_gate_vma(current->mm))

			vm_flags_clear(vma, VM_LOCKED_MASK);

		else

			mm->locked_vm += (len >> PAGE_SHIFT);

			mm->locked_vm += pglen;

	}



	if (file)