Re: [edk2 UsbMassStorageDxe v1 1/1] MdeModulePkg/Usb: Replace macro USB_BOOT_IO_BLOCKS

["Zeng, Star" <star.zeng@intel.com>]

Ming,

Basically, I am ok with the change in this patch. There are two comments.

1. Please add more background information about the specific device in the commit log. For example, you mentioned " like some virtual CD-ROM from BMC " in previous patch.
2. Please make sure building pass with the patch on different tool chains. I tried to build with the patch on VS2015, but met building failure like below.
warning C4244: '=': conversion from 'UINT32' to 'UINT16', possible loss of data


Ray,

Do you have other concern?


Thanks,
Star
-----Original Message-----
From: Ming Huang [mailto:ming.huang@linaro.org] 
Sent: Thursday, March 15, 2018 8:30 PM
To: leif.lindholm@linaro.org; linaro-uefi@lists.linaro.org; edk2-devel@lists.01.org; Zeng, Star <star.zeng@intel.com>; Dong, Eric <eric.dong@intel.com>
Cc: ard.biesheuvel@linaro.org; Kinney, Michael D <michael.d.kinney@intel.com>; Gao, Liming <liming.gao@intel.com>; guoheyi@huawei.com; wanghuiqiang@huawei.com; huangming23@huawei.com; zhangjinsong2@huawei.com; mengfanrong@huawei.com; huangdaode@hisilicon.com; waip23@126.com; Ming Huang <ming.huang@linaro.org>
Subject: [edk2 UsbMassStorageDxe v1 1/1] MdeModulePkg/Usb: Replace macro USB_BOOT_IO_BLOCKS

Booting from USB may fail while the macro USB_BOOT_IO_BLOCKS set to 128 because the block size of some USB devices are exceeded 512. So,the count blocks to transfer should be calculated by block size of the USB devices.

Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Ming Huang <ming.huang@linaro.org>
---
 MdeModulePkg/Bus/Usb/UsbMassStorageDxe/UsbMassBoot.c | 16 ++++++++++++----  MdeModulePkg/Bus/Usb/UsbMassStorageDxe/UsbMassBoot.h |  4 ++--
 2 files changed, 14 insertions(+), 6 deletions(-)

diff --git a/MdeModulePkg/Bus/Usb/UsbMassStorageDxe/UsbMassBoot.c b/MdeModulePkg/Bus/Usb/UsbMassStorageDxe/UsbMassBoot.c
index b84bfd2d7290..b38cb6116bf4 100644
--- a/MdeModulePkg/Bus/Usb/UsbMassStorageDxe/UsbMassBoot.c
+++ b/MdeModulePkg/Bus/Usb/UsbMassStorageDxe/UsbMassBoot.c
@@ -814,11 +814,13 @@ UsbBootReadBlocks (
   USB_BOOT_READ10_CMD       ReadCmd;
   EFI_STATUS                Status;
   UINT16                    Count;
+  UINT16                    CountMax;
   UINT32                    BlockSize;
   UINT32                    ByteSize;
   UINT32                    Timeout;
 
   BlockSize = UsbMass->BlockIoMedia.BlockSize;
+  CountMax = USB_BOOT_MAX_CARRY_SIZE / BlockSize;
   Status    = EFI_SUCCESS;
 
   while (TotalBlock > 0) {
@@ -827,7 +829,7 @@ UsbBootReadBlocks (
     // on the device. We must split the total block because the READ10
     // command only has 16 bit transfer length (in the unit of block).
     //
-    Count     = (UINT16)((TotalBlock < USB_BOOT_IO_BLOCKS) ? TotalBlock : USB_BOOT_IO_BLOCKS);
+    Count     = (UINT16)((TotalBlock < CountMax) ? TotalBlock : CountMax);
     ByteSize  = (UINT32)Count * BlockSize;
 
     //
@@ -890,11 +892,13 @@ UsbBootWriteBlocks (
   USB_BOOT_WRITE10_CMD  WriteCmd;
   EFI_STATUS            Status;
   UINT16                Count;
+  UINT16                CountMax;
   UINT32                BlockSize;
   UINT32                ByteSize;
   UINT32                Timeout;
 
   BlockSize = UsbMass->BlockIoMedia.BlockSize;
+  CountMax = USB_BOOT_MAX_CARRY_SIZE / BlockSize;
   Status    = EFI_SUCCESS;
 
   while (TotalBlock > 0) {
@@ -903,7 +907,7 @@ UsbBootWriteBlocks (
     // on the device. We must split the total block because the WRITE10
     // command only has 16 bit transfer length (in the unit of block).
     //
-    Count     = (UINT16)((TotalBlock < USB_BOOT_IO_BLOCKS) ? TotalBlock : USB_BOOT_IO_BLOCKS);
+    Count     = (UINT16)((TotalBlock < CountMax) ? TotalBlock : CountMax);
     ByteSize  = (UINT32)Count * BlockSize;
 
     //
@@ -966,18 +970,20 @@ UsbBootReadBlocks16 (
   UINT8                     ReadCmd[16];
   EFI_STATUS                Status;
   UINT16                    Count;
+  UINT16                    CountMax;
   UINT32                    BlockSize;
   UINT32                    ByteSize;
   UINT32                    Timeout;
 
   BlockSize = UsbMass->BlockIoMedia.BlockSize;
+  CountMax = USB_BOOT_MAX_CARRY_SIZE / BlockSize;
   Status    = EFI_SUCCESS;
 
   while (TotalBlock > 0) {
     //
     // Split the total blocks into smaller pieces.
     //
-    Count     = (UINT16)((TotalBlock < USB_BOOT_IO_BLOCKS) ? TotalBlock : USB_BOOT_IO_BLOCKS);
+    Count     = (UINT16)((TotalBlock < CountMax) ? TotalBlock : CountMax);
     ByteSize  = (UINT32)Count * BlockSize;
 
     //
@@ -1040,18 +1046,20 @@ UsbBootWriteBlocks16 (
   UINT8                 WriteCmd[16];
   EFI_STATUS            Status;
   UINT16                Count;
+  UINT16                CountMax;
   UINT32                BlockSize;
   UINT32                ByteSize;
   UINT32                Timeout;
 
   BlockSize = UsbMass->BlockIoMedia.BlockSize;
+  CountMax = USB_BOOT_MAX_CARRY_SIZE / BlockSize;
   Status    = EFI_SUCCESS;
 
   while (TotalBlock > 0) {
     //
     // Split the total blocks into smaller pieces.
     //
-    Count     = (UINT16)((TotalBlock < USB_BOOT_IO_BLOCKS) ? TotalBlock : USB_BOOT_IO_BLOCKS);
+    Count     = (UINT16)((TotalBlock < CountMax) ? TotalBlock : CountMax);
     ByteSize  = (UINT32)Count * BlockSize;
 
     //
diff --git a/MdeModulePkg/Bus/Usb/UsbMassStorageDxe/UsbMassBoot.h b/MdeModulePkg/Bus/Usb/UsbMassStorageDxe/UsbMassBoot.h
index 13a926035ceb..fc5449bde21e 100644
--- a/MdeModulePkg/Bus/Usb/UsbMassStorageDxe/UsbMassBoot.h
+++ b/MdeModulePkg/Bus/Usb/UsbMassStorageDxe/UsbMassBoot.h
@@ -65,9 +65,9 @@ WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
 #define USB_PDT_SIMPLE_DIRECT           0x0E       ///< Simplified direct access device
 
 //
-// Other parameters, Max carried size is 512B * 128 = 64KB
+// Other parameters, Max carried size is 64KB.
 //
-#define USB_BOOT_IO_BLOCKS              128
+#define USB_BOOT_MAX_CARRY_SIZE         0x10000
 
 //
 // Retry mass command times, set by experience
--
1.9.1