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-rw-r--r--include/block/block.h11
1 files changed, 6 insertions, 5 deletions
diff --git a/include/block/block.h b/include/block/block.h
index f85e3a6ed3..4e0871aaf9 100644
--- a/include/block/block.h
+++ b/include/block/block.h
@@ -43,11 +43,12 @@ typedef struct BlockFragInfo {
typedef enum {
BDRV_REQ_COPY_ON_READ = 0x1,
BDRV_REQ_ZERO_WRITE = 0x2,
- /* The BDRV_REQ_MAY_UNMAP flag is used to indicate that the block driver
- * is allowed to optimize a write zeroes request by unmapping (discarding)
- * blocks if it is guaranteed that the result will read back as
- * zeroes. The flag is only passed to the driver if the block device is
- * opened with BDRV_O_UNMAP.
+
+ /*
+ * The BDRV_REQ_MAY_UNMAP flag is used in write_zeroes requests to indicate
+ * that the block driver should unmap (discard) blocks if it is guaranteed
+ * that the result will read back as zeroes. The flag is only passed to the
+ * driver if the block device is opened with BDRV_O_UNMAP.
*/
BDRV_REQ_MAY_UNMAP = 0x4,