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Diffstat (limited to 'include/uapi/linux/ublk_cmd.h')
-rw-r--r--include/uapi/linux/ublk_cmd.h22
1 files changed, 21 insertions, 1 deletions
diff --git a/include/uapi/linux/ublk_cmd.h b/include/uapi/linux/ublk_cmd.h
index 640bf687b94a..c0c1632c671e 100644
--- a/include/uapi/linux/ublk_cmd.h
+++ b/include/uapi/linux/ublk_cmd.h
@@ -93,9 +93,29 @@
#define UBLKSRV_CMD_BUF_OFFSET 0
#define UBLKSRV_IO_BUF_OFFSET 0x80000000
-/* tag bit is 12bit, so at most 4096 IOs for each queue */
+/* tag bit is 16bit, so far limit at most 4096 IOs for each queue */
#define UBLK_MAX_QUEUE_DEPTH 4096
+/* single IO buffer max size is 32MB */
+#define UBLK_IO_BUF_OFF 0
+#define UBLK_IO_BUF_BITS 25
+#define UBLK_IO_BUF_BITS_MASK ((1ULL << UBLK_IO_BUF_BITS) - 1)
+
+/* so at most 64K IOs for each queue */
+#define UBLK_TAG_OFF UBLK_IO_BUF_BITS
+#define UBLK_TAG_BITS 16
+#define UBLK_TAG_BITS_MASK ((1ULL << UBLK_TAG_BITS) - 1)
+
+/* max 4096 queues */
+#define UBLK_QID_OFF (UBLK_TAG_OFF + UBLK_TAG_BITS)
+#define UBLK_QID_BITS 12
+#define UBLK_QID_BITS_MASK ((1ULL << UBLK_QID_BITS) - 1)
+
+#define UBLK_MAX_NR_QUEUES (1U << UBLK_QID_BITS)
+
+#define UBLKSRV_IO_BUF_TOTAL_BITS (UBLK_QID_OFF + UBLK_QID_BITS)
+#define UBLKSRV_IO_BUF_TOTAL_SIZE (1ULL << UBLKSRV_IO_BUF_TOTAL_BITS)
+
/*
* zero copy requires 4k block size, and can remap ublk driver's io
* request into ublksrv's vm space