summaryrefslogtreecommitdiffstats
path: root/mm/mmap.c
diff options
context:
space:
mode:
Diffstat (limited to 'mm/mmap.c')
-rw-r--r--mm/mmap.c58
1 files changed, 26 insertions, 32 deletions
diff --git a/mm/mmap.c b/mm/mmap.c
index bf2122af94e7..87d929316d57 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -226,8 +226,7 @@ SYSCALL_DEFINE1(brk, unsigned long, brk)
/* Search one past newbrk */
mas_set(&mas, newbrk);
brkvma = mas_find(&mas, oldbrk);
- BUG_ON(brkvma == NULL);
- if (brkvma->vm_start >= oldbrk)
+ if (!brkvma || brkvma->vm_start >= oldbrk)
goto out; /* mapping intersects with an existing non-brk vma. */
/*
* mm->brk must be protected by write mmap_lock.
@@ -456,7 +455,7 @@ void vma_mas_remove(struct vm_area_struct *vma, struct ma_state *mas)
* vma_mas_szero() - Set a given range to zero. Used when modifying a
* vm_area_struct start or end.
*
- * @mm: The struct_mm
+ * @mas: The maple tree ma_state
* @start: The start address to zero
* @end: The end address to zero.
*/
@@ -618,7 +617,8 @@ int __vma_adjust(struct vm_area_struct *vma, unsigned long start,
struct vm_area_struct *expand)
{
struct mm_struct *mm = vma->vm_mm;
- struct vm_area_struct *next_next, *next = find_vma(mm, vma->vm_end);
+ struct vm_area_struct *next_next = NULL; /* uninit var warning */
+ struct vm_area_struct *next = find_vma(mm, vma->vm_end);
struct vm_area_struct *orig_vma = vma;
struct address_space *mapping = NULL;
struct rb_root_cached *root = NULL;
@@ -1778,9 +1778,6 @@ get_unmapped_area(struct file *file, unsigned long addr, unsigned long len,
*/
pgoff = 0;
get_area = shmem_get_unmapped_area;
- } else if (IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE)) {
- /* Ensures that larger anonymous mappings are THP aligned. */
- get_area = thp_get_unmapped_area;
}
addr = get_area(file, addr, len, pgoff, flags);
@@ -2625,14 +2622,14 @@ cannot_expand:
if (error)
goto unmap_and_free_vma;
- /* Can addr have changed??
- *
- * Answer: Yes, several device drivers can do it in their
- * f_op->mmap method. -DaveM
+ /*
+ * Expansion is handled above, merging is handled below.
+ * Drivers should not alter the address of the VMA.
*/
- WARN_ON_ONCE(addr != vma->vm_start);
-
- addr = vma->vm_start;
+ if (WARN_ON((addr != vma->vm_start))) {
+ error = -EINVAL;
+ goto close_and_free_vma;
+ }
mas_reset(&mas);
/*
@@ -2654,7 +2651,6 @@ cannot_expand:
vm_area_free(vma);
vma = merge;
/* Update vm_flags to pick up the change. */
- addr = vma->vm_start;
vm_flags = vma->vm_flags;
goto unmap_writable;
}
@@ -2674,6 +2670,8 @@ cannot_expand:
error = -EINVAL;
if (file)
goto close_and_free_vma;
+ else if (vma->vm_file)
+ goto unmap_and_free_vma;
else
goto free_vma;
}
@@ -2681,6 +2679,8 @@ cannot_expand:
if (mas_preallocate(&mas, vma, GFP_KERNEL)) {
error = -ENOMEM;
if (file)
+ goto close_and_free_vma;
+ else if (vma->vm_file)
goto unmap_and_free_vma;
else
goto free_vma;
@@ -2751,7 +2751,7 @@ unmap_and_free_vma:
/* Undo any partial mapping done by a device driver. */
unmap_region(mm, mas.tree, vma, prev, next, vma->vm_start, vma->vm_end);
- if (vm_flags & VM_SHARED)
+ if (file && (vm_flags & VM_SHARED))
mapping_unmap_writable(file->f_mapping);
free_vma:
vm_area_free(vma);
@@ -2852,6 +2852,9 @@ SYSCALL_DEFINE5(remap_file_pages, unsigned long, start, unsigned long, size,
if (next->vm_flags != vma->vm_flags)
goto out;
+ if (start + size <= next->vm_end)
+ break;
+
prev = next;
}
@@ -2942,12 +2945,12 @@ static int do_brk_flags(struct ma_state *mas, struct vm_area_struct *vma,
* Expand the existing vma if possible; Note that singular lists do not
* occur after forking, so the expand will only happen on new VMAs.
*/
- if (vma &&
- (!vma->anon_vma || list_is_singular(&vma->anon_vma_chain)) &&
- ((vma->vm_flags & ~VM_SOFTDIRTY) == flags)) {
+ if (vma && vma->vm_end == addr && !vma_policy(vma) &&
+ can_vma_merge_after(vma, flags, NULL, NULL,
+ addr >> PAGE_SHIFT, NULL_VM_UFFD_CTX, NULL)) {
mas_set_range(mas, vma->vm_start, addr + len - 1);
if (mas_preallocate(mas, vma, GFP_KERNEL))
- return -ENOMEM;
+ goto unacct_fail;
vma_adjust_trans_huge(vma, vma->vm_start, addr + len, 0);
if (vma->anon_vma) {
@@ -2969,7 +2972,7 @@ static int do_brk_flags(struct ma_state *mas, struct vm_area_struct *vma,
/* create a vma struct for an anonymous mapping */
vma = vm_area_alloc(mm);
if (!vma)
- goto vma_alloc_fail;
+ goto unacct_fail;
vma_set_anonymous(vma);
vma->vm_start = addr;
@@ -2994,7 +2997,7 @@ out:
mas_store_fail:
vm_area_free(vma);
-vma_alloc_fail:
+unacct_fail:
vm_unacct_memory(len >> PAGE_SHIFT);
return -ENOMEM;
}
@@ -3031,11 +3034,6 @@ int vm_brk_flags(unsigned long addr, unsigned long request, unsigned long flags)
goto munmap_failed;
vma = mas_prev(&mas, 0);
- if (!vma || vma->vm_end != addr || vma_policy(vma) ||
- !can_vma_merge_after(vma, flags, NULL, NULL,
- addr >> PAGE_SHIFT, NULL_VM_UFFD_CTX, NULL))
- vma = NULL;
-
ret = do_brk_flags(&mas, vma, addr, len, flags);
populate = ((mm->def_flags & VM_LOCKED) != 0);
mmap_write_unlock(mm);
@@ -3746,13 +3744,9 @@ static int reserve_mem_notifier(struct notifier_block *nb,
return NOTIFY_OK;
}
-static struct notifier_block reserve_mem_nb = {
- .notifier_call = reserve_mem_notifier,
-};
-
static int __meminit init_reserve_notifier(void)
{
- if (register_hotmemory_notifier(&reserve_mem_nb))
+ if (hotplug_memory_notifier(reserve_mem_notifier, DEFAULT_CALLBACK_PRI))
pr_err("Failed registering memory add/remove notifier for admin reserve\n");
return 0;
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-06 02:02:37 +0000