* Note this is a helper function intended to be used by LSMs which
* wish to use this logic.
*/
-int __vm_enough_memory(long pages, int cap_sys_admin)
+int __vm_enough_memory(struct mm_struct *mm, long pages, int cap_sys_admin)
{
unsigned long free, allowed;
/* Don't let a single process grow too big:
leave 3% of the size of this process for other processes */
- allowed -= current->mm->total_vm / 32;
+ allowed -= mm->total_vm / 32;
/*
* cast `allowed' as a signed long because vm_committed_space
unsigned long flags, unsigned long pgoff)
{
struct mm_struct * mm = current->mm;
- struct vm_area_struct * vma, * prev;
struct inode *inode;
unsigned int vm_flags;
- int correct_wcount = 0;
int error;
- struct rb_node ** rb_link, * rb_parent;
int accountable = 1;
- unsigned long charged = 0, reqprot = prot;
+ unsigned long reqprot = prot;
/*
* Does the application expect PROT_READ to imply PROT_EXEC?
}
}
- error = security_file_mmap(file, reqprot, prot, flags);
+ error = security_file_mmap(file, reqprot, prot, flags, addr, 0);
if (error)
return error;
-
+
+ return mmap_region(file, addr, len, flags, vm_flags, pgoff,
+ accountable);
+}
+EXPORT_SYMBOL(do_mmap_pgoff);
+
+/*
+ * Some shared mappigns will want the pages marked read-only
+ * to track write events. If so, we'll downgrade vm_page_prot
+ * to the private version (using protection_map[] without the
+ * VM_SHARED bit).
+ */
+int vma_wants_writenotify(struct vm_area_struct *vma)
+{
+ unsigned int vm_flags = vma->vm_flags;
+
+ /* If it was private or non-writable, the write bit is already clear */
+ if ((vm_flags & (VM_WRITE|VM_SHARED)) != ((VM_WRITE|VM_SHARED)))
+ return 0;
+
+ /* The backer wishes to know when pages are first written to? */
+ if (vma->vm_ops && vma->vm_ops->page_mkwrite)
+ return 1;
+
+ /* The open routine did something to the protections already? */
+ if (pgprot_val(vma->vm_page_prot) !=
+ pgprot_val(protection_map[vm_flags &
+ (VM_READ|VM_WRITE|VM_EXEC|VM_SHARED)]))
+ return 0;
+
+ /* Specialty mapping? */
+ if (vm_flags & (VM_PFNMAP|VM_INSERTPAGE))
+ return 0;
+
+ /* Can the mapping track the dirty pages? */
+ return vma->vm_file && vma->vm_file->f_mapping &&
+ mapping_cap_account_dirty(vma->vm_file->f_mapping);
+}
+
+
+unsigned long mmap_region(struct file *file, unsigned long addr,
+ unsigned long len, unsigned long flags,
+ unsigned int vm_flags, unsigned long pgoff,
+ int accountable)
+{
+ struct mm_struct *mm = current->mm;
+ struct vm_area_struct *vma, *prev;
+ int correct_wcount = 0;
+ int error;
+ struct rb_node **rb_link, *rb_parent;
+ unsigned long charged = 0;
+ struct inode *inode = file ? file->f_path.dentry->d_inode : NULL;
+
/* Clear old maps */
error = -ENOMEM;
munmap_back:
mm->locked_vm += len >> PAGE_SHIFT;
make_pages_present(addr, addr + len);
}
- if (flags & MAP_POPULATE) {
- up_write(&mm->mmap_sem);
- sys_remap_file_pages(addr, len, 0,
- pgoff, flags & MAP_NONBLOCK);
- down_write(&mm->mmap_sem);
- }
+ if ((flags & MAP_POPULATE) && !(flags & MAP_NONBLOCK))
+ make_pages_present(addr, addr + len);
return addr;
unmap_and_free_vma:
return error;
}
-EXPORT_SYMBOL(do_mmap_pgoff);
-
/* Get an address range which is currently unmapped.
* For shmat() with addr=0.
*
* vma->vm_start/vm_end cannot change under us because the caller
* is required to hold the mmap_sem in read mode. We need the
* anon_vma lock to serialize against concurrent expand_stacks.
+ * Also guard against wrapping around to address 0.
*/
- address += 4 + PAGE_SIZE - 1;
- address &= PAGE_MASK;
+ if (address < PAGE_ALIGN(address+4))
+ address = PAGE_ALIGN(address+4);
+ else {
+ anon_vma_unlock(vma);
+ return -ENOMEM;
+ }
error = 0;
/* Somebody else might have raced and expanded it already */
}
#endif /* CONFIG_STACK_GROWSUP || CONFIG_IA64 */
-#ifdef CONFIG_STACK_GROWSUP
-int expand_stack(struct vm_area_struct *vma, unsigned long address)
-{
- return expand_upwards(vma, address);
-}
-
-struct vm_area_struct *
-find_extend_vma(struct mm_struct *mm, unsigned long addr)
-{
- struct vm_area_struct *vma, *prev;
-
- addr &= PAGE_MASK;
- vma = find_vma_prev(mm, addr, &prev);
- if (vma && (vma->vm_start <= addr))
- return vma;
- if (!prev || expand_stack(prev, addr))
- return NULL;
- if (prev->vm_flags & VM_LOCKED) {
- make_pages_present(addr, prev->vm_end);
- }
- return prev;
-}
-#else
/*
* vma is the first one with address < vma->vm_start. Have to extend vma.
*/
-int expand_stack(struct vm_area_struct *vma, unsigned long address)
+static inline int expand_downwards(struct vm_area_struct *vma,
+ unsigned long address)
{
int error;
return error;
}
+int expand_stack_downwards(struct vm_area_struct *vma, unsigned long address)
+{
+ return expand_downwards(vma, address);
+}
+
+#ifdef CONFIG_STACK_GROWSUP
+int expand_stack(struct vm_area_struct *vma, unsigned long address)
+{
+ return expand_upwards(vma, address);
+}
+
+struct vm_area_struct *
+find_extend_vma(struct mm_struct *mm, unsigned long addr)
+{
+ struct vm_area_struct *vma, *prev;
+
+ addr &= PAGE_MASK;
+ vma = find_vma_prev(mm, addr, &prev);
+ if (vma && (vma->vm_start <= addr))
+ return vma;
+ if (!prev || expand_stack(prev, addr))
+ return NULL;
+ if (prev->vm_flags & VM_LOCKED)
+ make_pages_present(addr, prev->vm_end);
+ return prev;
+}
+#else
+int expand_stack(struct vm_area_struct *vma, unsigned long address)
+{
+ return expand_downwards(vma, address);
+}
+
struct vm_area_struct *
find_extend_vma(struct mm_struct * mm, unsigned long addr)
{
start = vma->vm_start;
if (expand_stack(vma, addr))
return NULL;
- if (vma->vm_flags & VM_LOCKED) {
+ if (vma->vm_flags & VM_LOCKED)
make_pages_present(addr, start);
- }
return vma;
}
#endif
/*
* Split a vma into two pieces at address 'addr', a new vma is allocated
- * either for the first part or the the tail.
+ * either for the first part or the tail.
*/
int split_vma(struct mm_struct * mm, struct vm_area_struct * vma,
unsigned long addr, int new_below)
if (__vma && __vma->vm_start < vma->vm_end)
return -ENOMEM;
if ((vma->vm_flags & VM_ACCOUNT) &&
- security_vm_enough_memory(vma_pages(vma)))
+ security_vm_enough_memory_mm(mm, vma_pages(vma)))
return -ENOMEM;
vma_link(mm, vma, prev, rb_link, rb_parent);
return 0;
git.samba.org / sfrench / cifs-2.6.git / blobdiff