When mremap call results in expansion, it might be possible to merge the
VMA with the next VMA which might become adjacent. This patch adds
vma_merge call after the expansion is done to try and merge.
Signed-off-by: Jakub Matěna <matenajakub@xxxxxxxxx>
---
mm/mremap.c | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)
diff --git a/mm/mremap.c b/mm/mremap.c
index 303d3290b938..21dfa15e8200 100644
--- a/mm/mremap.c
+++ b/mm/mremap.c
@@ -9,6 +9,7 @@
*/
#include <linux/mm.h>
+#include <linux/mm_inline.h>
#include <linux/hugetlb.h>
#include <linux/shm.h>
#include <linux/ksm.h>
@@ -23,6 +24,7 @@
#include <linux/mmu_notifier.h>
#include <linux/uaccess.h>
#include <linux/userfaultfd_k.h>
+#include <linux/mempolicy.h>
#include <asm/cacheflush.h>
#include <asm/tlb.h>
@@ -1022,8 +1024,11 @@ SYSCALL_DEFINE5(mremap, unsigned long, addr, unsigned long, old_len,
}
}
- if (vma_adjust(vma, vma->vm_start, addr + new_len,
- vma->vm_pgoff, NULL)) {
+ vma = vma_merge(mm, vma, addr + old_len, addr + new_len,
+ vma->vm_flags, vma->anon_vma, vma->vm_file,
+ vma->vm_pgoff + (old_len >> PAGE_SHIFT), vma_policy(vma),
+ vma->vm_userfaultfd_ctx, anon_vma_name(vma));
+ if (!vma) {
vm_unacct_memory(pages);
ret = -ENOMEM;
goto out;
--
2.35.1
