From c154124fe925a451e471233aa7d1ab9a91f0a5ad Mon Sep 17 00:00:00 2001 From: "Liam R. Howlett" Date: Tue, 6 Sep 2022 19:49:06 +0000 Subject: [PATCH] mm/mmap.c: pass in mapping to __vma_link_file() __vma_link_file() resolves the mapping from the file, if there is one. Pass through the mapping and check the vm_file externally since most places already have the required information and check of vm_file. Link: https://lkml.kernel.org/r/20220906194824.2110408-71-Liam.Howlett@oracle.com Signed-off-by: Liam R. Howlett Tested-by: Yu Zhao Cc: Catalin Marinas Cc: David Hildenbrand Cc: David Howells Cc: Davidlohr Bueso Cc: "Matthew Wilcox (Oracle)" Cc: SeongJae Park Cc: Sven Schnelle Cc: Vlastimil Babka Cc: Will Deacon Signed-off-by: Andrew Morton --- mm/mmap.c | 29 ++++++++++++----------------- 1 file changed, 12 insertions(+), 17 deletions(-) diff --git a/mm/mmap.c b/mm/mmap.c index 5070af6..fbe8b52 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -407,21 +407,15 @@ static unsigned long count_vma_pages_range(struct mm_struct *mm, return nr_pages; } -static void __vma_link_file(struct vm_area_struct *vma) +static void __vma_link_file(struct vm_area_struct *vma, + struct address_space *mapping) { - struct file *file; - - file = vma->vm_file; - if (file) { - struct address_space *mapping = file->f_mapping; - - if (vma->vm_flags & VM_SHARED) - mapping_allow_writable(mapping); + if (vma->vm_flags & VM_SHARED) + mapping_allow_writable(mapping); - flush_dcache_mmap_lock(mapping); - vma_interval_tree_insert(vma, &mapping->i_mmap); - flush_dcache_mmap_unlock(mapping); - } + flush_dcache_mmap_lock(mapping); + vma_interval_tree_insert(vma, &mapping->i_mmap); + flush_dcache_mmap_unlock(mapping); } /* @@ -488,10 +482,11 @@ static int vma_link(struct mm_struct *mm, struct vm_area_struct *vma) } vma_mas_store(vma, &mas); - __vma_link_file(vma); - if (mapping) + if (mapping) { + __vma_link_file(vma, mapping); i_mmap_unlock_write(mapping); + } mm->map_count++; validate_mm(mm); @@ -730,14 +725,14 @@ int __vma_adjust(struct vm_area_struct *vma, unsigned long start, uprobe_munmap(next, next->vm_start, next->vm_end); i_mmap_lock_write(mapping); - if (insert) { + if (insert && insert->vm_file) { /* * Put into interval tree now, so instantiated pages * are visible to arm/parisc __flush_dcache_page * throughout; but we cannot insert into address * space until vma start or end is updated. */ - __vma_link_file(insert); + __vma_link_file(insert, insert->vm_file->f_mapping); } } -- 2.7.4