diff mbox series

[v7,07/10] mmc: core: Adjust ACMD22 to SDUC

Message ID 20240908102018.3711527-8-avri.altman@wdc.com
State New
Headers show
Series Add SDUC Support | expand

Commit Message

Avri Altman Sept. 8, 2024, 10:20 a.m. UTC
ACMD22 is used to verify the previously write operation.  Normally, it
returns the number of written sectors as u32.  SDUC, however, returns it
as u64.  This is not a superfluous requirement, because SDUC writes may
exceeds 2TB.  For Linux mmc however, the previously write operation
could not be more than the block layer limits, thus we make room for a
u64 and cast the returning value to u32.

Reviewed-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Avri Altman <avri.altman@wdc.com>
---
 drivers/mmc/core/block.c | 24 ++++++++++++++++++------
 1 file changed, 18 insertions(+), 6 deletions(-)
diff mbox series

Patch

diff --git a/drivers/mmc/core/block.c b/drivers/mmc/core/block.c
index 308d7c1dd0b0..74b56198ce42 100644
--- a/drivers/mmc/core/block.c
+++ b/drivers/mmc/core/block.c
@@ -50,6 +50,7 @@ 
 #include <linux/mmc/sd.h>
 
 #include <linux/uaccess.h>
+#include <asm/unaligned.h>
 
 #include "queue.h"
 #include "block.h"
@@ -993,11 +994,10 @@  static int mmc_sd_num_wr_blocks(struct mmc_card *card, u32 *written_blocks)
 	int err;
 	u32 result;
 	__be32 *blocks;
-
+	u8 resp_sz = mmc_card_ult_capacity(card) ? 8 : 4;
 	struct mmc_request mrq = {};
 	struct mmc_command cmd = {};
 	struct mmc_data data = {};
-
 	struct scatterlist sg;
 
 	err = mmc_app_cmd(card->host, card);
@@ -1008,7 +1008,7 @@  static int mmc_sd_num_wr_blocks(struct mmc_card *card, u32 *written_blocks)
 	cmd.arg = 0;
 	cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_ADTC;
 
-	data.blksz = 4;
+	data.blksz = resp_sz;
 	data.blocks = 1;
 	data.flags = MMC_DATA_READ;
 	data.sg = &sg;
@@ -1018,15 +1018,27 @@  static int mmc_sd_num_wr_blocks(struct mmc_card *card, u32 *written_blocks)
 	mrq.cmd = &cmd;
 	mrq.data = &data;
 
-	blocks = kmalloc(4, GFP_KERNEL);
+	blocks = kmalloc(resp_sz, GFP_KERNEL);
 	if (!blocks)
 		return -ENOMEM;
 
-	sg_init_one(&sg, blocks, 4);
+	sg_init_one(&sg, blocks, resp_sz);
 
 	mmc_wait_for_req(card->host, &mrq);
 
-	result = ntohl(*blocks);
+	if (mmc_card_ult_capacity(card)) {
+		/*
+		 * Normally, ACMD22 returns the number of written sectors as
+		 * u32. SDUC, however, returns it as u64.  This is not a
+		 * superfluous requirement, because SDUC writes may exceed 2TB.
+		 * For Linux mmc however, the previously write operation could
+		 * not be more than the block layer limits, thus just make room
+		 * for a u64 and cast the response back to u32.
+		 */
+		result = clamp_val(get_unaligned_be64(blocks), 0, UINT_MAX);
+	} else {
+		result = ntohl(*blocks);
+	}
 	kfree(blocks);
 
 	if (cmd.error || data.error)