1 files changed, 30 insertions, 32 deletions

diff --git a/mm/filemap.c b/mm/filemap.c
index b7749a92021c..7a13f6ac5421 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -409,9 +409,9 @@ int replace_page_cache_page(struct page *old, struct page *new, gfp_t gfp_mask)
 {
         int error;
 
-        VM_BUG_ON(!PageLocked(old));
-        VM_BUG_ON(!PageLocked(new));
-        VM_BUG_ON(new->mapping);
+        VM_BUG_ON_PAGE(!PageLocked(old), old);
+        VM_BUG_ON_PAGE(!PageLocked(new), new);
+        VM_BUG_ON_PAGE(new->mapping, new);
 
         error = radix_tree_preload(gfp_mask & ~__GFP_HIGHMEM);
         if (!error) {
@@ -461,8 +461,8 @@ int add_to_page_cache_locked(struct page *page, struct address_space *mapping,
 {
         int error;
 
-        VM_BUG_ON(!PageLocked(page));
-        VM_BUG_ON(PageSwapBacked(page));
+        VM_BUG_ON_PAGE(!PageLocked(page), page);
+        VM_BUG_ON_PAGE(PageSwapBacked(page), page);
 
         error = mem_cgroup_cache_charge(page, current->mm,
                                         gfp_mask & GFP_RECLAIM_MASK);
@@ -607,7 +607,7 @@ EXPORT_SYMBOL_GPL(add_page_wait_queue);
  */
 void unlock_page(struct page *page)
 {
-        VM_BUG_ON(!PageLocked(page));
+        VM_BUG_ON_PAGE(!PageLocked(page), page);
         clear_bit_unlock(PG_locked, &page->flags);
         smp_mb__after_clear_bit();
         wake_up_page(page, PG_locked);
@@ -760,7 +760,7 @@ repeat:
                         page_cache_release(page);
                         goto repeat;
                 }
-                VM_BUG_ON(page->index != offset);
+                VM_BUG_ON_PAGE(page->index != offset, page);
         }
         return page;
 }
@@ -1428,30 +1428,28 @@ generic_file_aio_read(struct kiocb *iocb, const struct iovec *iov,
                 if (!count)
                         goto out; /* skip atime */
                 size = i_size_read(inode);
-                if (pos < size) {
-                        retval = filemap_write_and_wait_range(mapping, pos,
+                retval = filemap_write_and_wait_range(mapping, pos,
                                         pos + iov_length(iov, nr_segs) - 1);
-                        if (!retval) {
-                                retval = mapping->a_ops->direct_IO(READ, iocb,
-                                                        iov, pos, nr_segs);
-                        }
-                        if (retval > 0) {
-                                *ppos = pos + retval;
-                                count -= retval;
-                        }
+                if (!retval) {
+                        retval = mapping->a_ops->direct_IO(READ, iocb,
+                                                           iov, pos, nr_segs);
+                }
+                if (retval > 0) {
+                        *ppos = pos + retval;
+                        count -= retval;
+                }
 
-                        /*
-                         * Btrfs can have a short DIO read if we encounter
-                         * compressed extents, so if there was an error, or if
-                         * we've already read everything we wanted to, or if
-                         * there was a short read because we hit EOF, go ahead
-                         * and return.  Otherwise fallthrough to buffered io for
-                         * the rest of the read.
-                         */
-                        if (retval < 0 || !count || *ppos >= size) {
-                                file_accessed(filp);
-                                goto out;
-                        }
+                /*
+                 * Btrfs can have a short DIO read if we encounter
+                 * compressed extents, so if there was an error, or if
+                 * we've already read everything we wanted to, or if
+                 * there was a short read because we hit EOF, go ahead
+                 * and return.  Otherwise fallthrough to buffered io for
+                 * the rest of the read.
+                 */
+                if (retval < 0 || !count || *ppos >= size) {
+                        file_accessed(filp);
+                        goto out;
                 }
         }
 
@@ -1656,7 +1654,7 @@ retry_find:
                 put_page(page);
                 goto retry_find;
         }
-        VM_BUG_ON(page->index != offset);
+        VM_BUG_ON_PAGE(page->index != offset, page);
 
         /*
          * We have a locked page in the page cache, now we need to check
@@ -2555,8 +2553,8 @@ ssize_t generic_file_aio_write(struct kiocb *iocb, const struct iovec *iov,
         if (ret > 0) {
                 ssize_t err;
 
-                err = generic_write_sync(file, pos, ret);
-                if (err < 0 && ret > 0)
+                err = generic_write_sync(file, iocb->ki_pos - ret, ret);
+                if (err < 0)
                         ret = err;
         }
         return ret;