diff mbox series

[105/181] mm/mmap: check on file instead of the rb_root_cached of its address_space

Message ID 20201013235407.PRKybZHOD%akpm@linux-foundation.org (mailing list archive)
State New, archived
Headers show
Series [001/181] compiler-clang: add build check for clang 10.0.1 | expand

Commit Message

Andrew Morton Oct. 13, 2020, 11:54 p.m. UTC 
From: Wei Yang <richard.weiyang@linux.alibaba.com>
Subject: mm/mmap: check on file instead of the rb_root_cached of its address_space

In __vma_adjust(), we do the check on *root* to decide whether to adjust
the address_space.  It seems to be more meaningful to do the check on
*file* itself.  This means we are adjusting some data because it is a file
backed vma.

Since we seem to assume the address_space is valid if it is a file backed
vma, let's just replace *root* with *file* here.

Link: https://lkml.kernel.org/r/20200913133631.37781-2-richard.weiyang@linux.alibaba.com
Signed-off-by: Wei Yang <richard.weiyang@linux.alibaba.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/mmap.c |    6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)
diff mbox series

Patch

--- a/mm/mmap.c~mm-mmap-check-on-file-instead-of-the-rb_root_cached-of-its-address_space
+++ a/mm/mmap.c
@@ -823,7 +823,7 @@  again:
 			anon_vma_interval_tree_pre_update_vma(next);
 	}
 
-	if (root) {
+	if (file) {
 		flush_dcache_mmap_lock(mapping);
 		vma_interval_tree_remove(vma, root);
 		if (adjust_next)
@@ -844,7 +844,7 @@  again:
 		next->vm_pgoff += adjust_next >> PAGE_SHIFT;
 	}
 
-	if (root) {
+	if (file) {
 		if (adjust_next)
 			vma_interval_tree_insert(next, root);
 		vma_interval_tree_insert(vma, root);
@@ -896,7 +896,7 @@  again:
 		anon_vma_unlock_write(anon_vma);
 	}
 
-	if (root) {
+	if (file) {
 		i_mmap_unlock_write(mapping);
 		uprobe_mmap(vma);