[Qemu-devel] [PATCH] block: fix big write

[Ming Lei]

From: Ming Lei <address@hidden>

QEMU block should have supported to read/write at most
0x7fffff * 512 bytes, unfortunately INT_MAX is used to check
bytes in both bdrv_co_do_writev() and bdrv_check_byte_request(),
so cause write failure if nr_sectors is equal or more
than 0x400000.

There are still other INT_MAX usages in block.c, and they might
need to change to UINT_MAX too in future, but at least
this patch's change can make SCSI WRITE SAME 16 workable.

Cc: address@hidden
Signed-off-by: Ming Lei <address@hidden>
---
 block.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/block.c b/block.c
index a612594..ddc18c2 100644
--- a/block.c
+++ b/block.c
@@ -2607,7 +2607,7 @@ static int bdrv_check_byte_request(BlockDriverState *bs, 
int64_t offset,
 {
     int64_t len;
 
-    if (size > INT_MAX) {
+    if (size > UINT_MAX) {
         return -EIO;
     }
 
@@ -3420,7 +3420,7 @@ static int coroutine_fn 
bdrv_co_do_writev(BlockDriverState *bs,
     int64_t sector_num, int nb_sectors, QEMUIOVector *qiov,
     BdrvRequestFlags flags)
 {
-    if (nb_sectors < 0 || nb_sectors > (INT_MAX >> BDRV_SECTOR_BITS)) {
+    if (nb_sectors < 0 || nb_sectors > (UINT_MAX >> BDRV_SECTOR_BITS)) {
         return -EINVAL;
     }
 
-- 
1.7.9.5