for sys_mmap(), added unmapping of existing vmas for the area that is soon to be mmap'ed.

This commit is contained in:
Bahadir Balban
2008-11-07 21:22:50 +02:00
parent daffc1d084
commit 99b7cf2274
2 changed files with 10 additions and 14 deletions

View File

@@ -147,9 +147,10 @@ void *do_mmap(struct vm_file *mapfile, unsigned long file_offset,
unsigned int flags, unsigned int npages)
{
unsigned long map_pfn = __pfn(map_address);
unsigned long file_npages;
struct vm_area *new, *mapped;
struct vm_obj_link *vmo_link, *vmo_link2;
unsigned long file_npages;
int err;
/* Set up devzero if none given */
if (!mapfile) {
@@ -185,18 +186,12 @@ void *do_mmap(struct vm_file *mapfile, unsigned long file_offset,
return PTR_ERR(-EINVAL);
else if (!(map_address = mmap_new_address(task, flags, npages)))
return PTR_ERR(-ENOMEM);
} else {
/*
* FIXME: Currently we don't allow overlapping vmas.
* To be fixed soon. We need to handle intersection,
* splitting, shrink/grow etc.
*/
list_for_each_entry(mapped, &task->vm_area_head->list, list)
BUG_ON(set_intersection(map_pfn, map_pfn + npages,
mapped->pfn_start,
mapped->pfn_end));
}
/* Unmap any existing vmas that overlap with the new mapping */
if ((err = do_munmap(task, map_address, npages)) < 0)
return PTR_ERR(err);
/* For valid regions that aren't allocated by us, create the vma. */
if (!(new = vma_new(__pfn(map_address), npages, flags, file_offset)))
return PTR_ERR(-ENOMEM);

View File

@@ -133,7 +133,7 @@ int vma_flush_pages(struct vm_area *vma)
* may span into zero or more vmas, and may involve shrinking, splitting
* and destruction of multiple vmas.
*/
int do_munmap(struct tcb *task, void *vaddr, unsigned long npages)
int do_munmap(struct tcb *task, unsigned long vaddr, unsigned long npages)
{
const unsigned long munmap_start = __pfn(vaddr);
const unsigned long munmap_end = munmap_start + npages;
@@ -167,10 +167,11 @@ int do_munmap(struct tcb *task, void *vaddr, unsigned long npages)
int sys_munmap(struct tcb *task, void *start, unsigned long length)
{
/* Must be aligned on a page boundary */
if ((unsigned long)start & PAGE_MASK)
if (!is_page_aligned(start))
return -EINVAL;
return do_munmap(task, start, __pfn(page_align_up(length)));
return do_munmap(task, (unsigned long)start,
__pfn(page_align_up(length)));
}