mm/xip: share the i_mmap_rwsem
__xip_unmap() will remove the xip sparse page from the cache and take down pte mapping, without altering the interval tree, thus share the i_mmap_rwsem when searching for the ptes to unmap. Additionally, tidy up the function a bit and make variables only local to the interval tree walk loop. Signed-off-by: Davidlohr Bueso <dbueso@suse.de> Acked-by: "Kirill A. Shutemov" <kirill@shutemov.name> Acked-by: Hugh Dickins <hughd@google.com> Cc: Oleg Nesterov <oleg@redhat.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Acked-by: Mel Gorman <mgorman@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
parent
4a23717a23
commit
874bfcaf79
|
@ -155,22 +155,14 @@ xip_file_read(struct file *filp, char __user *buf, size_t len, loff_t *ppos)
|
||||||
EXPORT_SYMBOL_GPL(xip_file_read);
|
EXPORT_SYMBOL_GPL(xip_file_read);
|
||||||
|
|
||||||
/*
|
/*
|
||||||
* __xip_unmap is invoked from xip_unmap and
|
* __xip_unmap is invoked from xip_unmap and xip_write
|
||||||
* xip_write
|
|
||||||
*
|
*
|
||||||
* This function walks all vmas of the address_space and unmaps the
|
* This function walks all vmas of the address_space and unmaps the
|
||||||
* __xip_sparse_page when found at pgoff.
|
* __xip_sparse_page when found at pgoff.
|
||||||
*/
|
*/
|
||||||
static void
|
static void __xip_unmap(struct address_space * mapping, unsigned long pgoff)
|
||||||
__xip_unmap (struct address_space * mapping,
|
|
||||||
unsigned long pgoff)
|
|
||||||
{
|
{
|
||||||
struct vm_area_struct *vma;
|
struct vm_area_struct *vma;
|
||||||
struct mm_struct *mm;
|
|
||||||
unsigned long address;
|
|
||||||
pte_t *pte;
|
|
||||||
pte_t pteval;
|
|
||||||
spinlock_t *ptl;
|
|
||||||
struct page *page;
|
struct page *page;
|
||||||
unsigned count;
|
unsigned count;
|
||||||
int locked = 0;
|
int locked = 0;
|
||||||
|
@ -182,11 +174,14 @@ __xip_unmap (struct address_space * mapping,
|
||||||
return;
|
return;
|
||||||
|
|
||||||
retry:
|
retry:
|
||||||
i_mmap_lock_write(mapping);
|
i_mmap_lock_read(mapping);
|
||||||
vma_interval_tree_foreach(vma, &mapping->i_mmap, pgoff, pgoff) {
|
vma_interval_tree_foreach(vma, &mapping->i_mmap, pgoff, pgoff) {
|
||||||
mm = vma->vm_mm;
|
pte_t *pte, pteval;
|
||||||
address = vma->vm_start +
|
spinlock_t *ptl;
|
||||||
|
struct mm_struct *mm = vma->vm_mm;
|
||||||
|
unsigned long address = vma->vm_start +
|
||||||
((pgoff - vma->vm_pgoff) << PAGE_SHIFT);
|
((pgoff - vma->vm_pgoff) << PAGE_SHIFT);
|
||||||
|
|
||||||
BUG_ON(address < vma->vm_start || address >= vma->vm_end);
|
BUG_ON(address < vma->vm_start || address >= vma->vm_end);
|
||||||
pte = page_check_address(page, mm, address, &ptl, 1);
|
pte = page_check_address(page, mm, address, &ptl, 1);
|
||||||
if (pte) {
|
if (pte) {
|
||||||
|
@ -202,7 +197,7 @@ retry:
|
||||||
page_cache_release(page);
|
page_cache_release(page);
|
||||||
}
|
}
|
||||||
}
|
}
|
||||||
i_mmap_unlock_write(mapping);
|
i_mmap_unlock_read(mapping);
|
||||||
|
|
||||||
if (locked) {
|
if (locked) {
|
||||||
mutex_unlock(&xip_sparse_mutex);
|
mutex_unlock(&xip_sparse_mutex);
|
||||||
|
|
Loading…
Reference in a new issue