diff mbox series

[PULL,09/20] block/io: allow 64bit write-zeroes requests

Message ID 20210927215545.3930309-10-eblake@redhat.com (mailing list archive)
State New, archived
Headers show
Series [PULL,01/20] qemu-nbd: Change default cache mode to writeback | expand

Commit Message

Eric Blake Sept. 27, 2021, 9:55 p.m. UTC 
From: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>

Now that all drivers are updated by previous commit, we can drop two
last limiters on write-zeroes path: INT_MAX in
bdrv_co_do_pwrite_zeroes() and bdrv_check_request32() in
bdrv_co_pwritev_part().

Now everything is prepared for implementing incredibly cool and fast
big-write-zeroes in NBD and qcow2. And any other driver which wants it
of course.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20210903102807.27127-9-vsementsov@virtuozzo.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
---
 block/io.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)
diff mbox series

Patch

diff --git a/block/io.c b/block/io.c
index 0090224603f5..e40462742ea1 100644
--- a/block/io.c
+++ b/block/io.c
@@ -1869,7 +1869,8 @@  static int coroutine_fn bdrv_co_do_pwrite_zeroes(BlockDriverState *bs,
     int head = 0;
     int tail = 0;

-    int64_t max_write_zeroes = MIN_NON_ZERO(bs->bl.max_pwrite_zeroes, INT_MAX);
+    int64_t max_write_zeroes = MIN_NON_ZERO(bs->bl.max_pwrite_zeroes,
+                                            INT64_MAX);
     int alignment = MAX(bs->bl.pwrite_zeroes_alignment,
                         bs->bl.request_alignment);
     int max_transfer = MIN_NON_ZERO(bs->bl.max_transfer, MAX_BOUNCE_BUFFER);
@@ -2248,7 +2249,11 @@  int coroutine_fn bdrv_co_pwritev_part(BdrvChild *child,
         return -ENOMEDIUM;
     }

-    ret = bdrv_check_request32(offset, bytes, qiov, qiov_offset);
+    if (flags & BDRV_REQ_ZERO_WRITE) {
+        ret = bdrv_check_qiov_request(offset, bytes, qiov, qiov_offset, NULL);
+    } else {
+        ret = bdrv_check_request32(offset, bytes, qiov, qiov_offset);
+    }
     if (ret < 0) {
         return ret;
     }