mmap: clean up mmap_region() unrolling
Move logic of unrolling to the error path as apposed to duplicating it within the function body. This reduces the potential of missing an update to one path when making changes. Link: https://lkml.kernel.org/r/20230120162650.984577-38-Liam.Howlett@oracle.com Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com> Cc: Li Zetao <lizetao1@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit is contained in:
parent
b373037fa9
commit
cc8d1b097d
47
mm/mmap.c
47
mm/mmap.c
|
@ -2601,12 +2601,11 @@ cannot_expand:
|
|||
* Expansion is handled above, merging is handled below.
|
||||
* Drivers should not alter the address of the VMA.
|
||||
*/
|
||||
if (WARN_ON((addr != vma->vm_start))) {
|
||||
error = -EINVAL;
|
||||
error = -EINVAL;
|
||||
if (WARN_ON((addr != vma->vm_start)))
|
||||
goto close_and_free_vma;
|
||||
}
|
||||
vma_iter_set(&vmi, addr);
|
||||
|
||||
vma_iter_set(&vmi, addr);
|
||||
/*
|
||||
* If vm_flags changed after call_mmap(), we should try merge
|
||||
* vma again as we may succeed this time.
|
||||
|
@ -2653,25 +2652,13 @@ cannot_expand:
|
|||
}
|
||||
|
||||
/* Allow architectures to sanity-check the vm_flags */
|
||||
if (!arch_validate_flags(vma->vm_flags)) {
|
||||
error = -EINVAL;
|
||||
if (file)
|
||||
goto close_and_free_vma;
|
||||
else if (vma->vm_file)
|
||||
goto unmap_and_free_vma;
|
||||
else
|
||||
goto free_vma;
|
||||
}
|
||||
error = -EINVAL;
|
||||
if (!arch_validate_flags(vma->vm_flags))
|
||||
goto close_and_free_vma;
|
||||
|
||||
if (vma_iter_prealloc(&vmi)) {
|
||||
error = -ENOMEM;
|
||||
if (file)
|
||||
goto close_and_free_vma;
|
||||
else if (vma->vm_file)
|
||||
goto unmap_and_free_vma;
|
||||
else
|
||||
goto free_vma;
|
||||
}
|
||||
error = -ENOMEM;
|
||||
if (vma_iter_prealloc(&vmi))
|
||||
goto close_and_free_vma;
|
||||
|
||||
if (vma->vm_file)
|
||||
i_mmap_lock_write(vma->vm_file->f_mapping);
|
||||
|
@ -2730,14 +2717,18 @@ expanded:
|
|||
return addr;
|
||||
|
||||
close_and_free_vma:
|
||||
if (vma->vm_ops && vma->vm_ops->close)
|
||||
if (file && vma->vm_ops && vma->vm_ops->close)
|
||||
vma->vm_ops->close(vma);
|
||||
unmap_and_free_vma:
|
||||
fput(vma->vm_file);
|
||||
vma->vm_file = NULL;
|
||||
|
||||
/* Undo any partial mapping done by a device driver. */
|
||||
unmap_region(mm, &mm->mm_mt, vma, prev, next, vma->vm_start, vma->vm_end);
|
||||
if (file || vma->vm_file) {
|
||||
unmap_and_free_vma:
|
||||
fput(vma->vm_file);
|
||||
vma->vm_file = NULL;
|
||||
|
||||
/* Undo any partial mapping done by a device driver. */
|
||||
unmap_region(mm, &mm->mm_mt, vma, prev, next, vma->vm_start,
|
||||
vma->vm_end);
|
||||
}
|
||||
if (file && (vm_flags & VM_SHARED))
|
||||
mapping_unmap_writable(file->f_mapping);
|
||||
free_vma:
|
||||
|
|
Loading…
Reference in New Issue