[PATCH] add AOP_TRUNCATED_PAGE, prepend AOP_ to WRITEPAGE_ACTIVATE

[linux-2.6.git] / drivers / block / loop.c

diff --git a/drivers/block/loop.c b/drivers/block/loop.c
index 96c664af8d069f9f5d96d77efea7b293f2549fe6..a452b13620a228739fe60f296e85720643bf03e0 100644 (file)
--- a/drivers/block/loop.c
+++ b/drivers/block/loop.c
@@ -213,7 +213,7 @@ static int do_lo_send_aops(struct loop_device *lo, struct bio_vec *bvec,
        struct address_space_operations *aops = mapping->a_ops;
        pgoff_t index;
        unsigned offset, bv_offs;
-       int len, ret = 0;
+       int len, ret;
 
        down(&mapping->host->i_sem);
        index = pos >> PAGE_CACHE_SHIFT;
@@ -232,9 +232,15 @@ static int do_lo_send_aops(struct loop_device *lo, struct bio_vec *bvec,
                page = grab_cache_page(mapping, index);
                if (unlikely(!page))
                        goto fail;
-               if (unlikely(aops->prepare_write(file, page, offset,
-                               offset + size)))
+               ret = aops->prepare_write(file, page, offset,
+                                         offset + size);
+               if (unlikely(ret)) {
+                       if (ret == AOP_TRUNCATED_PAGE) {
+                               page_cache_release(page);
+                               continue;
+                       }
                        goto unlock;
+               }
                transfer_result = lo_do_transfer(lo, WRITE, page, offset,
                                bvec->bv_page, bv_offs, size, IV);
                if (unlikely(transfer_result)) {
@@ -251,9 +257,15 @@ static int do_lo_send_aops(struct loop_device *lo, struct bio_vec *bvec,
                        kunmap_atomic(kaddr, KM_USER0);
                }
                flush_dcache_page(page);
-               if (unlikely(aops->commit_write(file, page, offset,
-                               offset + size)))
+               ret = aops->commit_write(file, page, offset,
+                                        offset + size);
+               if (unlikely(ret)) {
+                       if (ret == AOP_TRUNCATED_PAGE) {
+                               page_cache_release(page);
+                               continue;
+                       }
                        goto unlock;
+               }
                if (unlikely(transfer_result))
                        goto unlock;
                bv_offs += size;
@@ -264,6 +276,7 @@ static int do_lo_send_aops(struct loop_device *lo, struct bio_vec *bvec,
                unlock_page(page);
                page_cache_release(page);
        }
+       ret = 0;
 out:
        up(&mapping->host->i_sem);
        return ret;