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-rw-r--r--mm/mmap.c89
1 files changed, 84 insertions, 5 deletions
diff --git a/mm/mmap.c b/mm/mmap.c
index 7be110e98d4c..eb509ae76553 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -188,7 +188,7 @@ static void __remove_shared_vm_struct(struct vm_area_struct *vma,
struct file *file, struct address_space *mapping)
{
if (vma->vm_flags & VM_DENYWRITE)
- atomic_inc(&file->f_dentry->d_inode->i_writecount);
+ atomic_inc(&file->f_path.dentry->d_inode->i_writecount);
if (vma->vm_flags & VM_SHARED)
mapping->i_mmap_writable--;
@@ -399,7 +399,7 @@ static inline void __vma_link_file(struct vm_area_struct *vma)
struct address_space *mapping = file->f_mapping;
if (vma->vm_flags & VM_DENYWRITE)
- atomic_dec(&file->f_dentry->d_inode->i_writecount);
+ atomic_dec(&file->f_path.dentry->d_inode->i_writecount);
if (vma->vm_flags & VM_SHARED)
mapping->i_mmap_writable++;
@@ -907,7 +907,7 @@ unsigned long do_mmap_pgoff(struct file * file, unsigned long addr,
* mounted, in which case we dont add PROT_EXEC.)
*/
if ((prot & PROT_READ) && (current->personality & READ_IMPLIES_EXEC))
- if (!(file && (file->f_vfsmnt->mnt_flags & MNT_NOEXEC)))
+ if (!(file && (file->f_path.mnt->mnt_flags & MNT_NOEXEC)))
prot |= PROT_EXEC;
if (!len)
@@ -960,7 +960,7 @@ unsigned long do_mmap_pgoff(struct file * file, unsigned long addr,
return -EAGAIN;
}
- inode = file ? file->f_dentry->d_inode : NULL;
+ inode = file ? file->f_path.dentry->d_inode : NULL;
if (file) {
switch (flags & MAP_TYPE) {
@@ -989,7 +989,7 @@ unsigned long do_mmap_pgoff(struct file * file, unsigned long addr,
case MAP_PRIVATE:
if (!(file->f_mode & FMODE_READ))
return -EACCES;
- if (file->f_vfsmnt->mnt_flags & MNT_NOEXEC) {
+ if (file->f_path.mnt->mnt_flags & MNT_NOEXEC) {
if (vm_flags & VM_EXEC)
return -EPERM;
vm_flags &= ~VM_MAYEXEC;
@@ -1477,6 +1477,7 @@ static int acct_stack_growth(struct vm_area_struct * vma, unsigned long size, un
{
struct mm_struct *mm = vma->vm_mm;
struct rlimit *rlim = current->signal->rlim;
+ unsigned long new_start;
/* address space limit tests */
if (!may_expand_vm(mm, grow))
@@ -1496,6 +1497,12 @@ static int acct_stack_growth(struct vm_area_struct * vma, unsigned long size, un
return -ENOMEM;
}
+ /* Check to ensure the stack will not grow into a hugetlb-only region */
+ new_start = (vma->vm_flags & VM_GROWSUP) ? vma->vm_start :
+ vma->vm_end - size;
+ if (is_hugepage_only_range(vma->vm_mm, new_start, size))
+ return -EFAULT;
+
/*
* Overcommit.. This must be the final test, as it will
* update security statistics.
@@ -2094,3 +2101,75 @@ int may_expand_vm(struct mm_struct *mm, unsigned long npages)
return 0;
return 1;
}
+
+
+static struct page *special_mapping_nopage(struct vm_area_struct *vma,
+ unsigned long address, int *type)
+{
+ struct page **pages;
+
+ BUG_ON(address < vma->vm_start || address >= vma->vm_end);
+
+ address -= vma->vm_start;
+ for (pages = vma->vm_private_data; address > 0 && *pages; ++pages)
+ address -= PAGE_SIZE;
+
+ if (*pages) {
+ struct page *page = *pages;
+ get_page(page);
+ return page;
+ }
+
+ return NOPAGE_SIGBUS;
+}
+
+/*
+ * Having a close hook prevents vma merging regardless of flags.
+ */
+static void special_mapping_close(struct vm_area_struct *vma)
+{
+}
+
+static struct vm_operations_struct special_mapping_vmops = {
+ .close = special_mapping_close,
+ .nopage = special_mapping_nopage,
+};
+
+/*
+ * Called with mm->mmap_sem held for writing.
+ * Insert a new vma covering the given region, with the given flags.
+ * Its pages are supplied by the given array of struct page *.
+ * The array can be shorter than len >> PAGE_SHIFT if it's null-terminated.
+ * The region past the last page supplied will always produce SIGBUS.
+ * The array pointer and the pages it points to are assumed to stay alive
+ * for as long as this mapping might exist.
+ */
+int install_special_mapping(struct mm_struct *mm,
+ unsigned long addr, unsigned long len,
+ unsigned long vm_flags, struct page **pages)
+{
+ struct vm_area_struct *vma;
+
+ vma = kmem_cache_zalloc(vm_area_cachep, GFP_KERNEL);
+ if (unlikely(vma == NULL))
+ return -ENOMEM;
+
+ vma->vm_mm = mm;
+ vma->vm_start = addr;
+ vma->vm_end = addr + len;
+
+ vma->vm_flags = vm_flags | mm->def_flags;
+ vma->vm_page_prot = protection_map[vma->vm_flags & 7];
+
+ vma->vm_ops = &special_mapping_vmops;
+ vma->vm_private_data = pages;
+
+ if (unlikely(insert_vm_struct(mm, vma))) {
+ kmem_cache_free(vm_area_cachep, vma);
+ return -ENOMEM;
+ }
+
+ mm->total_vm += len >> PAGE_SHIFT;
+
+ return 0;
+}
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