[Qemu-devel] [PATCH 2/4] block: immediately cancel oversized read/write requests

[Peter Lieven]

Signed-off-by: Peter Lieven <address@hidden>
---
 block.c |   14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/block.c b/block.c
index 2c4a5de..fa4c34b 100644
--- a/block.c
+++ b/block.c
@@ -3215,6 +3215,13 @@ static int coroutine_fn 
bdrv_co_do_readv(BlockDriverState *bs,
         return -EINVAL;
     }
 
+    if (bs->bl.max_transfer_length && nb_sectors > bs->bl.max_transfer_length) 
{
+        error_report("read of %d sectors at sector %ld exceeds device max"
+                     " transfer length of %d sectors.", nb_sectors, sector_num,
+                     bs->bl.max_transfer_length);
+        return -EINVAL;
+    }
+
     return bdrv_co_do_preadv(bs, sector_num << BDRV_SECTOR_BITS,
                              nb_sectors << BDRV_SECTOR_BITS, qiov, flags);
 }
@@ -3507,6 +3514,13 @@ static int coroutine_fn 
bdrv_co_do_writev(BlockDriverState *bs,
         return -EINVAL;
     }
 
+    if (bs->bl.max_transfer_length && nb_sectors > bs->bl.max_transfer_length) 
{
+        error_report("write of %d sectors at sector %ld exceeds device max"
+                     " transfer length of %d sectors.", nb_sectors, sector_num,
+                     bs->bl.max_transfer_length);
+        return -EINVAL;
+    }
+
     return bdrv_co_do_pwritev(bs, sector_num << BDRV_SECTOR_BITS,
                               nb_sectors << BDRV_SECTOR_BITS, qiov, flags);
 }
-- 
1.7.9.5