diff options
Diffstat (limited to 'mm/mremap.c')
| -rw-r--r-- | mm/mremap.c | 19 |
1 files changed, 17 insertions, 2 deletions
diff --git a/mm/mremap.c b/mm/mremap.c index 8644ff278f02..e465ffe279bb 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> @@ -1012,6 +1014,9 @@ SYSCALL_DEFINE5(mremap, unsigned long, addr, unsigned long, old_len, /* can we just expand the current mapping? */ if (vma_expandable(vma, new_len - old_len)) { long pages = (new_len - old_len) >> PAGE_SHIFT; + unsigned long extension_start = addr + old_len; + unsigned long extension_end = addr + new_len; + pgoff_t extension_pgoff = vma->vm_pgoff + (old_len >> PAGE_SHIFT); if (vma->vm_flags & VM_ACCOUNT) { if (security_vm_enough_memory_mm(mm, pages)) { @@ -1020,8 +1025,18 @@ SYSCALL_DEFINE5(mremap, unsigned long, addr, unsigned long, old_len, } } - if (vma_adjust(vma, vma->vm_start, addr + new_len, - vma->vm_pgoff, NULL)) { + /* + * Function vma_merge() is called on the extension we are adding to + * the already existing vma, vma_merge() will merge this extension with + * the already existing vma (expand operation itself) and possibly also + * with the next vma if it becomes adjacent to the expanded vma and + * otherwise compatible. + */ + vma = vma_merge(mm, vma, extension_start, extension_end, + vma->vm_flags, vma->anon_vma, vma->vm_file, + extension_pgoff, vma_policy(vma), + vma->vm_userfaultfd_ctx, anon_vma_name(vma)); + if (!vma) { vm_unacct_memory(pages); ret = -ENOMEM; goto out; |