[SCSI] sr,sd: send media state change modification events

[linux-2.6-omap-h63xx.git] / mm / mmap.c

diff --git a/mm/mmap.c b/mm/mmap.c
index 7afc7a7cec6f681001817ad6656d3a20d9ed53a7..15678aa6ec73a4389d1c523fe542144cd3050836 100644 (file)
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -7,6 +7,7 @@
  */
 
 #include <linux/slab.h>
+#include <linux/backing-dev.h>
 #include <linux/mm.h>
 #include <linux/shm.h>
 #include <linux/mman.h>
@@ -93,7 +94,7 @@ atomic_t vm_committed_space = ATOMIC_INIT(0);
  * 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;
 
@@ -166,7 +167,7 @@ int __vm_enough_memory(long pages, int cap_sys_admin)
 
        /* 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
@@ -180,8 +181,6 @@ error:
        return -ENOMEM;
 }
 
-EXPORT_SYMBOL(__vm_enough_memory);
-
 /*
  * Requires inode->i_mapping->i_mmap_lock
  */
@@ -913,6 +912,9 @@ unsigned long do_mmap_pgoff(struct file * file, unsigned long addr,
        if (!len)
                return -EINVAL;
 
+       if (!(flags & MAP_FIXED))
+               addr = round_hint_to_min(addr);
+
        error = arch_mmap_check(addr, len, flags);
        if (error)
                return error;
@@ -1029,6 +1031,39 @@ unsigned long do_mmap_pgoff(struct file * file, unsigned long addr,
 }
 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(vm_get_page_prot(vm_flags)))
+               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,
@@ -1097,8 +1132,7 @@ munmap_back:
        vma->vm_start = addr;
        vma->vm_end = addr + len;
        vma->vm_flags = vm_flags;
-       vma->vm_page_prot = protection_map[vm_flags &
-                               (VM_READ|VM_WRITE|VM_EXEC|VM_SHARED)];
+       vma->vm_page_prot = vm_get_page_prot(vm_flags);
        vma->vm_pgoff = pgoff;
 
        if (file) {
@@ -1140,8 +1174,7 @@ munmap_back:
        vm_flags = vma->vm_flags;
 
        if (vma_wants_writenotify(vma))
-               vma->vm_page_prot =
-                       protection_map[vm_flags & (VM_READ|VM_WRITE|VM_EXEC)];
+               vma->vm_page_prot = vm_get_page_prot(vm_flags & ~VM_SHARED);
 
        if (!file || !vma_merge(mm, prev, addr, vma->vm_end,
                        vma->vm_flags, NULL, file, pgoff, vma_policy(vma))) {
@@ -1585,6 +1618,12 @@ static inline int expand_downwards(struct vm_area_struct *vma,
         */
        if (unlikely(anon_vma_prepare(vma)))
                return -ENOMEM;
+
+       address &= PAGE_MASK;
+       error = security_file_mmap(0, 0, 0, 0, address, 1);
+       if (error)
+               return error;
+
        anon_vma_lock(vma);
 
        /*
@@ -1592,8 +1631,6 @@ static inline int expand_downwards(struct vm_area_struct *vma,
         * is required to hold the mmap_sem in read mode.  We need the
         * anon_vma lock to serialize against concurrent expand_stacks.
         */
-       address &= PAGE_MASK;
-       error = 0;
 
        /* Somebody else might have raced and expanded it already */
        if (address < vma->vm_start) {
@@ -1904,6 +1941,10 @@ unsigned long do_brk(unsigned long addr, unsigned long len)
        if (is_hugepage_only_range(mm, addr, len))
                return -EINVAL;
 
+       error = security_file_mmap(0, 0, 0, 0, addr, 1);
+       if (error)
+               return error;
+
        flags = VM_DATA_DEFAULT_FLAGS | VM_ACCOUNT | mm->def_flags;
 
        error = arch_mmap_check(addr, len, flags);
@@ -1969,8 +2010,7 @@ unsigned long do_brk(unsigned long addr, unsigned long len)
        vma->vm_end = addr + len;
        vma->vm_pgoff = pgoff;
        vma->vm_flags = flags;
-       vma->vm_page_prot = protection_map[flags &
-                               (VM_READ|VM_WRITE|VM_EXEC|VM_SHARED)];
+       vma->vm_page_prot = vm_get_page_prot(flags);
        vma_link(mm, vma, prev, rb_link, rb_parent);
 out:
        mm->total_vm += len >> PAGE_SHIFT;
@@ -2043,7 +2083,7 @@ int insert_vm_struct(struct mm_struct * mm, struct vm_area_struct * vma)
        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;
@@ -2176,7 +2216,7 @@ int install_special_mapping(struct mm_struct *mm,
        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_page_prot = vm_get_page_prot(vma->vm_flags);
 
        vma->vm_ops = &special_mapping_vmops;
        vma->vm_private_data = pages;