Commit bedbac5f authored by Nikita Yushchenko's avatar Nikita Yushchenko Committed by Greg Kroah-Hartman
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usb: gadget: storage: add support for media larger than 2T 



This adds support for READ_CAPACITY(16), READ(16) and WRITE(16)
commands, and fixes READ_CAPACITY command to return 0xffffffff if
media size does not fit in 32 bits.

This makes f_mass_storage to export a 16T disk array correctly.

Signed-off-by: default avatarNikita Yushchenko <nikita.yoush@cogentembedded.com>
Acked-by: default avatarAlan Stern <stern@rowland.harvard.edu>
Link: https://lore.kernel.org/r/20210921145901.11952-1-nikita.yoush@cogentembedded.com


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 05735f08

drivers/usb/gadget/function/f_mass_storage.c

+80 −7
Original line number Diff line number Diff line
@@ -588,7 +588,7 @@ static int sleep_thread(struct fsg_common *common, bool can_freeze, 
static int do_read(struct fsg_common *common)

{

	struct fsg_lun		*curlun = common->curlun;

	u32			lba;

	u64			lba;

	struct fsg_buffhd	*bh;

	int			rc;

	u32			amount_left;
@@ -603,6 +603,9 @@ static int do_read(struct fsg_common *common) 
	if (common->cmnd[0] == READ_6)

		lba = get_unaligned_be24(&common->cmnd[1]);

	else {

		if (common->cmnd[0] == READ_16)

			lba = get_unaligned_be64(&common->cmnd[2]);

		else		/* READ_10 or READ_12 */

			lba = get_unaligned_be32(&common->cmnd[2]);



		/*
@@ -716,7 +719,7 @@ static int do_read(struct fsg_common *common) 
static int do_write(struct fsg_common *common)

{

	struct fsg_lun		*curlun = common->curlun;

	u32			lba;

	u64			lba;

	struct fsg_buffhd	*bh;

	int			get_some_more;

	u32			amount_left_to_req, amount_left_to_write;
@@ -740,6 +743,9 @@ static int do_write(struct fsg_common *common) 
	if (common->cmnd[0] == WRITE_6)

		lba = get_unaligned_be24(&common->cmnd[1]);

	else {

		if (common->cmnd[0] == WRITE_16)

			lba = get_unaligned_be64(&common->cmnd[2]);

		else		/* WRITE_10 or WRITE_12 */

			lba = get_unaligned_be32(&common->cmnd[2]);



		/*
@@ -1115,6 +1121,7 @@ static int do_read_capacity(struct fsg_common *common, struct fsg_buffhd *bh) 
	u32		lba = get_unaligned_be32(&common->cmnd[2]);

	int		pmi = common->cmnd[8];

	u8		*buf = (u8 *)bh->buf;

	u32		max_lba;



	/* Check the PMI and LBA fields */

	if (pmi > 1 || (pmi == 0 && lba != 0)) {
@@ -1122,12 +1129,37 @@ static int do_read_capacity(struct fsg_common *common, struct fsg_buffhd *bh) 
		return -EINVAL;

	}



	put_unaligned_be32(curlun->num_sectors - 1, &buf[0]);

						/* Max logical block */

	if (curlun->num_sectors < 0x100000000ULL)

		max_lba = curlun->num_sectors - 1;

	else

		max_lba = 0xffffffff;

	put_unaligned_be32(max_lba, &buf[0]);		/* Max logical block */

	put_unaligned_be32(curlun->blksize, &buf[4]);	/* Block length */

	return 8;

}



static int do_read_capacity_16(struct fsg_common *common, struct fsg_buffhd *bh)

{

	struct fsg_lun  *curlun = common->curlun;

	u64		lba = get_unaligned_be64(&common->cmnd[2]);

	int		pmi = common->cmnd[14];

	u8		*buf = (u8 *)bh->buf;



	/* Check the PMI and LBA fields */

	if (pmi > 1 || (pmi == 0 && lba != 0)) {

		curlun->sense_data = SS_INVALID_FIELD_IN_CDB;

		return -EINVAL;

	}



	put_unaligned_be64(curlun->num_sectors - 1, &buf[0]);

							/* Max logical block */

	put_unaligned_be32(curlun->blksize, &buf[8]);	/* Block length */



	/* It is safe to keep other fields zeroed */

	memset(&buf[12], 0, 32 - 12);

	return 32;

}



static int do_read_header(struct fsg_common *common, struct fsg_buffhd *bh)

{

	struct fsg_lun	*curlun = common->curlun;
@@ -1874,6 +1906,17 @@ static int do_scsi_command(struct fsg_common *common) 
			reply = do_read(common);

		break;



	case READ_16:

		common->data_size_from_cmnd =

				get_unaligned_be32(&common->cmnd[10]);

		reply = check_command_size_in_blocks(common, 16,

				      DATA_DIR_TO_HOST,

				      (1<<1) | (0xff<<2) | (0xf<<10), 1,

				      "READ(16)");

		if (reply == 0)

			reply = do_read(common);

		break;



	case READ_CAPACITY:

		common->data_size_from_cmnd = 8;

		reply = check_command(common, 10, DATA_DIR_TO_HOST,
@@ -1926,6 +1969,25 @@ static int do_scsi_command(struct fsg_common *common) 
			reply = do_request_sense(common, bh);

		break;



	case SERVICE_ACTION_IN_16:

		switch (common->cmnd[1] & 0x1f) {



		case SAI_READ_CAPACITY_16:

			common->data_size_from_cmnd =

				get_unaligned_be32(&common->cmnd[10]);

			reply = check_command(common, 16, DATA_DIR_TO_HOST,

					      (1<<1) | (0xff<<2) | (0xf<<10) |

					      (1<<14), 1,

					      "READ CAPACITY(16)");

			if (reply == 0)

				reply = do_read_capacity_16(common, bh);

			break;



		default:

			goto unknown_cmnd;

		}

		break;



	case START_STOP:

		common->data_size_from_cmnd = 0;

		reply = check_command(common, 6, DATA_DIR_NONE,
@@ -1997,6 +2059,17 @@ static int do_scsi_command(struct fsg_common *common) 
			reply = do_write(common);

		break;



	case WRITE_16:

		common->data_size_from_cmnd =

				get_unaligned_be32(&common->cmnd[10]);

		reply = check_command_size_in_blocks(common, 16,

				      DATA_DIR_FROM_HOST,

				      (1<<1) | (0xff<<2) | (0xf<<10), 1,

				      "WRITE(16)");

		if (reply == 0)

			reply = do_write(common);

		break;



	/*

	 * Some mandatory commands that we recognize but don't implement.

	 * They don't mean much in this setting.  It's left as an exercise