int sysctl_overcommit_memory = OVERCOMMIT_GUESS; /* heuristic overcommit */
int sysctl_overcommit_ratio = 50; /* default is 50% */
int sysctl_max_map_count = DEFAULT_MAX_MAP_COUNT;
-int sysctl_nr_trim_pages = 1; /* page trimming behaviour */
+int sysctl_nr_trim_pages = CONFIG_NOMMU_INITIAL_TRIM_EXCESS;
int heap_stack_gap = 0;
atomic_long_t mmap_pages_allocated;
}
int __get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
- unsigned long start, int len, int flags,
- struct page **pages, struct vm_area_struct **vmas)
+ unsigned long start, int nr_pages, int flags,
+ struct page **pages, struct vm_area_struct **vmas)
{
struct vm_area_struct *vma;
unsigned long vm_flags;
vm_flags = write ? (VM_WRITE | VM_MAYWRITE) : (VM_READ | VM_MAYREAD);
vm_flags &= force ? (VM_MAYREAD | VM_MAYWRITE) : (VM_READ | VM_WRITE);
- for (i = 0; i < len; i++) {
+ for (i = 0; i < nr_pages; i++) {
vma = find_vma(mm, start);
if (!vma)
goto finish_or_fault;
* - don't permit access to VMAs that don't support it, such as I/O mappings
*/
int get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
- unsigned long start, int len, int write, int force,
+ unsigned long start, int nr_pages, int write, int force,
struct page **pages, struct vm_area_struct **vmas)
{
int flags = 0;
if (force)
flags |= GUP_FLAGS_FORCE;
- return __get_user_pages(tsk, mm,
- start, len, flags,
- pages, vmas);
+ return __get_user_pages(tsk, mm, start, nr_pages, flags, pages, vmas);
}
EXPORT_SYMBOL(get_user_pages);
+/**
+ * follow_pfn - look up PFN at a user virtual address
+ * @vma: memory mapping
+ * @address: user virtual address
+ * @pfn: location to store found PFN
+ *
+ * Only IO mappings and raw PFN mappings are allowed.
+ *
+ * Returns zero and the pfn at @pfn on success, -ve otherwise.
+ */
+int follow_pfn(struct vm_area_struct *vma, unsigned long address,
+ unsigned long *pfn)
+{
+ if (!(vma->vm_flags & (VM_IO | VM_PFNMAP)))
+ return -EINVAL;
+
+ *pfn = address >> PAGE_SHIFT;
+ return 0;
+}
+EXPORT_SYMBOL(follow_pfn);
+
DEFINE_RWLOCK(vmlist_lock);
struct vm_struct *vmlist;
validate_nommu_regions();
- BUG_ON(region->vm_start & ~PAGE_MASK);
-
parent = NULL;
p = &nommu_region_tree.rb_node;
while (*p) {
if (!file->f_op->read)
capabilities &= ~BDI_CAP_MAP_COPY;
+ /* The file shall have been opened with read permission. */
+ if (!(file->f_mode & FMODE_READ))
+ return -EACCES;
+
if (flags & MAP_SHARED) {
/* do checks for writing, appending and locking */
if ((prot & PROT_WRITE) &&
}
vma->vm_region = region;
+ add_nommu_region(region);
/* set up the mapping */
if (file && vma->vm_flags & VM_SHARED)
if (ret < 0)
goto error_put_region;
- add_nommu_region(region);
-
/* okay... we have a mapping; now we have to register it */
result = vma->vm_start;