Re: [Qemu-devel] [PATCH v3 16/29] block: Make zero-after-EOF work with larger alignment

2014-01-22 Thread Benoît Canet 
Le Friday 17 Jan 2014 à 15:15:06 (+0100), Kevin Wolf a écrit :
 Odd file sizes could make bdrv_aligned_preadv() shorten the request in
 non-aligned ways. Fix it by rounding to the required alignment instead
 of 512 bytes.
 
 Signed-off-by: Kevin Wolf kw...@redhat.com
 ---
  block.c | 7 ---
  1 file changed, 4 insertions(+), 3 deletions(-)
 
 diff --git a/block.c b/block.c
 index 18dcd43..d7156ce 100644
 --- a/block.c
 +++ b/block.c
 @@ -2730,7 +2730,7 @@ err:
   */
  static int coroutine_fn bdrv_aligned_preadv(BlockDriverState *bs,
  BdrvTrackedRequest *req, int64_t offset, unsigned int bytes,
 -QEMUIOVector *qiov, int flags)
 +int64_t align, QEMUIOVector *qiov, int flags)
  {
  BlockDriver *drv = bs-drv;
  int ret;
 @@ -2778,7 +2778,8 @@ static int coroutine_fn 
 bdrv_aligned_preadv(BlockDriverState *bs,
  }
  
  total_sectors = DIV_ROUND_UP(len, BDRV_SECTOR_SIZE);
 -max_nb_sectors = MAX(0, total_sectors - sector_num);
 +max_nb_sectors = MAX(0, ROUND_UP(total_sectors - sector_num,
 + align  BDRV_SECTOR_BITS));
  if (max_nb_sectors  0) {
  ret = drv-bdrv_co_readv(bs, sector_num,
   MIN(nb_sectors, max_nb_sectors), qiov);
 @@ -2864,7 +2865,7 @@ static int coroutine_fn 
 bdrv_co_do_preadv(BlockDriverState *bs,
  }
  
  tracked_request_begin(req, bs, offset, bytes, false);
 -ret = bdrv_aligned_preadv(bs, req, offset, bytes,
 +ret = bdrv_aligned_preadv(bs, req, offset, bytes, align,
use_local_qiov ? local_qiov : qiov,
flags);
  tracked_request_end(req);
 -- 
 1.8.1.4
 
 
Reviewed-by: Benoit Canet ben...@irqsave.net

[Qemu-devel] [PATCH v3 16/29] block: Make zero-after-EOF work with larger alignment

2014-01-17 Thread Kevin Wolf 
Odd file sizes could make bdrv_aligned_preadv() shorten the request in
non-aligned ways. Fix it by rounding to the required alignment instead
of 512 bytes.

Signed-off-by: Kevin Wolf kw...@redhat.com
---
 block.c | 7 ---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/block.c b/block.c
index 18dcd43..d7156ce 100644
--- a/block.c
+++ b/block.c
@@ -2730,7 +2730,7 @@ err:
  */
 static int coroutine_fn bdrv_aligned_preadv(BlockDriverState *bs,
 BdrvTrackedRequest *req, int64_t offset, unsigned int bytes,
-QEMUIOVector *qiov, int flags)
+int64_t align, QEMUIOVector *qiov, int flags)
 {
 BlockDriver *drv = bs-drv;
 int ret;
@@ -2778,7 +2778,8 @@ static int coroutine_fn 
bdrv_aligned_preadv(BlockDriverState *bs,
 }
 
 total_sectors = DIV_ROUND_UP(len, BDRV_SECTOR_SIZE);
-max_nb_sectors = MAX(0, total_sectors - sector_num);
+max_nb_sectors = MAX(0, ROUND_UP(total_sectors - sector_num,
+ align  BDRV_SECTOR_BITS));
 if (max_nb_sectors  0) {
 ret = drv-bdrv_co_readv(bs, sector_num,
  MIN(nb_sectors, max_nb_sectors), qiov);
@@ -2864,7 +2865,7 @@ static int coroutine_fn 
bdrv_co_do_preadv(BlockDriverState *bs,
 }
 
 tracked_request_begin(req, bs, offset, bytes, false);
-ret = bdrv_aligned_preadv(bs, req, offset, bytes,
+ret = bdrv_aligned_preadv(bs, req, offset, bytes, align,
   use_local_qiov ? local_qiov : qiov,
   flags);
 tracked_request_end(req);
-- 
1.8.1.4

Re: [Qemu-devel] [PATCH v3 16/29] block: Make zero-after-EOF work with larger alignment

2014-01-17 Thread Max Reitz 

On 17.01.2014 15:15, Kevin Wolf wrote:

Odd file sizes could make bdrv_aligned_preadv() shorten the request in
non-aligned ways. Fix it by rounding to the required alignment instead
of 512 bytes.

Signed-off-by: Kevin Wolf kw...@redhat.com
---
  block.c | 7 ---
  1 file changed, 4 insertions(+), 3 deletions(-)


Reviewed-by: Max Reitz mre...@redhat.com