[ARM] 4808/2: ixp4xx: Merge nas100d-power.c into nas100d-setup.c
[sfrench/cifs-2.6.git] / mm / filemap.c
index 7c8643630023d239f099335f4a80480d5bde0a02..89ce6fe5f8be152e71218085af5396dcb72d315c 100644 (file)
@@ -124,6 +124,18 @@ void __remove_from_page_cache(struct page *page)
        mapping->nrpages--;
        __dec_zone_page_state(page, NR_FILE_PAGES);
        BUG_ON(page_mapped(page));
+
+       /*
+        * Some filesystems seem to re-dirty the page even after
+        * the VM has canceled the dirty bit (eg ext3 journaling).
+        *
+        * Fix it up by doing a final dirty accounting check after
+        * having removed the page entirely.
+        */
+       if (PageDirty(page) && mapping_cap_account_dirty(mapping)) {
+               dec_zone_page_state(page, NR_FILE_DIRTY);
+               dec_bdi_stat(mapping->backing_dev_info, BDI_RECLAIMABLE);
+       }
 }
 
 void remove_from_page_cache(struct page *page)
@@ -173,6 +185,12 @@ static int sync_page(void *word)
        return 0;
 }
 
+static int sync_page_killable(void *word)
+{
+       sync_page(word);
+       return fatal_signal_pending(current) ? -EINTR : 0;
+}
+
 /**
  * __filemap_fdatawrite_range - start writeback on mapping dirty pages in range
  * @mapping:   address space structure to write
@@ -577,6 +595,14 @@ void fastcall __lock_page(struct page *page)
 }
 EXPORT_SYMBOL(__lock_page);
 
+int fastcall __lock_page_killable(struct page *page)
+{
+       DEFINE_WAIT_BIT(wait, &page->flags, PG_locked);
+
+       return __wait_on_bit_lock(page_waitqueue(page), &wait,
+                                       sync_page_killable, TASK_KILLABLE);
+}
+
 /*
  * Variant of lock_page that does not require the caller to hold a reference
  * on the page's mapping.
@@ -968,7 +994,8 @@ page_ok:
 
 page_not_up_to_date:
                /* Get exclusive access to the page ... */
-               lock_page(page);
+               if (lock_page_killable(page))
+                       goto readpage_eio;
 
                /* Did it get truncated before we got the lock? */
                if (!page->mapping) {
@@ -996,7 +1023,8 @@ readpage:
                }
 
                if (!PageUptodate(page)) {
-                       lock_page(page);
+                       if (lock_page_killable(page))
+                               goto readpage_eio;
                        if (!PageUptodate(page)) {
                                if (page->mapping == NULL) {
                                        /*
@@ -1007,15 +1035,16 @@ readpage:
                                        goto find_page;
                                }
                                unlock_page(page);
-                               error = -EIO;
                                shrink_readahead_size_eio(filp, ra);
-                               goto readpage_error;
+                               goto readpage_eio;
                        }
                        unlock_page(page);
                }
 
                goto page_ok;
 
+readpage_eio:
+               error = -EIO;
 readpage_error:
                /* UHHUH! A synchronous read error occurred. Report it */
                desc->error = error;
@@ -1300,7 +1329,7 @@ int filemap_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
 
        size = (i_size_read(inode) + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
        if (vmf->pgoff >= size)
-               goto outside_data_content;
+               return VM_FAULT_SIGBUS;
 
        /* If we don't want any read-ahead, don't bother */
        if (VM_RandomReadHint(vma))
@@ -1377,7 +1406,7 @@ retry_find:
        if (unlikely(vmf->pgoff >= size)) {
                unlock_page(page);
                page_cache_release(page);
-               goto outside_data_content;
+               return VM_FAULT_SIGBUS;
        }
 
        /*
@@ -1388,15 +1417,6 @@ retry_find:
        vmf->page = page;
        return ret | VM_FAULT_LOCKED;
 
-outside_data_content:
-       /*
-        * An external ptracer can access pages that normally aren't
-        * accessible..
-        */
-       if (vma->vm_mm == current->mm)
-               return VM_FAULT_SIGBUS;
-
-       /* Fall through to the non-read-ahead case */
 no_cached_page:
        /*
         * We're only likely to ever get here if MADV_RANDOM is in
@@ -2511,21 +2531,17 @@ generic_file_direct_IO(int rw, struct kiocb *iocb, const struct iovec *iov,
        }
 
        retval = mapping->a_ops->direct_IO(rw, iocb, iov, offset, nr_segs);
-       if (retval)
-               goto out;
 
        /*
         * Finally, try again to invalidate clean pages which might have been
-        * faulted in by get_user_pages() if the source of the write was an
-        * mmap()ed region of the file we're writing.  That's a pretty crazy
-        * thing to do, so we don't support it 100%.  If this invalidation
-        * fails and we have -EIOCBQUEUED we ignore the failure.
+        * cached by non-direct readahead, or faulted in by get_user_pages()
+        * if the source of the write was an mmap'ed region of the file
+        * we're writing.  Either one is a pretty crazy thing to do,
+        * so we don't support it 100%.  If this invalidation
+        * fails, tough, the write still worked...
         */
        if (rw == WRITE && mapping->nrpages) {
-               int err = invalidate_inode_pages2_range(mapping,
-                                             offset >> PAGE_CACHE_SHIFT, end);
-               if (err && retval >= 0)
-                       retval = err;
+               invalidate_inode_pages2_range(mapping, offset >> PAGE_CACHE_SHIFT, end);
        }
 out:
        return retval;