diff mbox series

[v3] usb: gadget: storage: add support for media larger than 2T

Message ID 20210921145901.11952-1-nikita.yoush@cogentembedded.com (mailing list archive)
State Accepted
Commit bedbac5f66bfcf54d500967417aeaa4088f6eae0
Headers show
Series [v3] usb: gadget: storage: add support for media larger than 2T | expand

Commit Message

Nikita Yushchenko Sept. 21, 2021, 2:59 p.m. UTC
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: Nikita Yushchenko <nikita.yoush@cogentembedded.com>
---
v3:
- added this changelog

v2:
- fixed call to check_command() for READ_CAPACITY(16)
- fixed alphabetical order of commands in switch statement
- renamed variable, added comments, and fixed formatting, per advices by
  Alan Stern <stern@rowland.harvard.edu>

 drivers/usb/gadget/function/f_mass_storage.c | 87 ++++++++++++++++++--
 1 file changed, 80 insertions(+), 7 deletions(-)

Comments

Greg KH Oct. 5, 2021, 11:07 a.m. UTC | #1
On Tue, Sep 21, 2021 at 05:59:02PM +0300, Nikita Yushchenko wrote:
> 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: Nikita Yushchenko <nikita.yoush@cogentembedded.com>
> ---
> v3:
> - added this changelog
> 
> v2:
> - fixed call to check_command() for READ_CAPACITY(16)
> - fixed alphabetical order of commands in switch statement
> - renamed variable, added comments, and fixed formatting, per advices by
>   Alan Stern <stern@rowland.harvard.edu>

Felipe and Alan, any objections to this change?

thanks,

greg k-h
Felipe Balbi Oct. 5, 2021, 12:07 p.m. UTC | #2
Hi,

Greg Kroah-Hartman <gregkh@linuxfoundation.org> writes:

> On Tue, Sep 21, 2021 at 05:59:02PM +0300, Nikita Yushchenko wrote:
>> 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: Nikita Yushchenko <nikita.yoush@cogentembedded.com>
>> ---
>> v3:
>> - added this changelog
>> 
>> v2:
>> - fixed call to check_command() for READ_CAPACITY(16)
>> - fixed alphabetical order of commands in switch statement
>> - renamed variable, added comments, and fixed formatting, per advices by
>>   Alan Stern <stern@rowland.harvard.edu>
>
> Felipe and Alan, any objections to this change?

none from me, but I'd definitely wait for Alan's comments as he's the
one who understands the storage gadget inside out :-)

cheers
Alan Stern Oct. 5, 2021, 2:19 p.m. UTC | #3
On Tue, Oct 05, 2021 at 01:07:58PM +0200, Greg Kroah-Hartman wrote:
> On Tue, Sep 21, 2021 at 05:59:02PM +0300, Nikita Yushchenko wrote:
> > 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: Nikita Yushchenko <nikita.yoush@cogentembedded.com>
> > ---
> > v3:
> > - added this changelog
> > 
> > v2:
> > - fixed call to check_command() for READ_CAPACITY(16)
> > - fixed alphabetical order of commands in switch statement
> > - renamed variable, added comments, and fixed formatting, per advices by
> >   Alan Stern <stern@rowland.harvard.edu>
> 
> Felipe and Alan, any objections to this change?

No objections.  In fact, I already sent my Acked-by for v2 of the 
patch (which is the same as v3):

https://marc.info/?l=linux-usb&m=163165151506682&w=2

Alan Stern
Greg KH Oct. 10, 2021, 1:08 p.m. UTC | #4
On Tue, Oct 05, 2021 at 10:19:58AM -0400, Alan Stern wrote:
> On Tue, Oct 05, 2021 at 01:07:58PM +0200, Greg Kroah-Hartman wrote:
> > On Tue, Sep 21, 2021 at 05:59:02PM +0300, Nikita Yushchenko wrote:
> > > 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: Nikita Yushchenko <nikita.yoush@cogentembedded.com>
> > > ---
> > > v3:
> > > - added this changelog
> > > 
> > > v2:
> > > - fixed call to check_command() for READ_CAPACITY(16)
> > > - fixed alphabetical order of commands in switch statement
> > > - renamed variable, added comments, and fixed formatting, per advices by
> > >   Alan Stern <stern@rowland.harvard.edu>
> > 
> > Felipe and Alan, any objections to this change?
> 
> No objections.  In fact, I already sent my Acked-by for v2 of the 
> patch (which is the same as v3):
> 
> https://marc.info/?l=linux-usb&m=163165151506682&w=2

Thanks, I had missed that.

And ick, marc.info, you might want to look at using lore.kernel.org in
the future :)

greg k-h
diff mbox series

Patch

diff --git a/drivers/usb/gadget/function/f_mass_storage.c b/drivers/usb/gadget/function/f_mass_storage.c
index 7c96c4665178..96de401f1282 100644
--- a/drivers/usb/gadget/function/f_mass_storage.c
+++ b/drivers/usb/gadget/function/f_mass_storage.c
@@ -619,7 +619,7 @@  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;
@@ -634,7 +634,10 @@  static int do_read(struct fsg_common *common)
 	if (common->cmnd[0] == READ_6)
 		lba = get_unaligned_be24(&common->cmnd[1]);
 	else {
-		lba = get_unaligned_be32(&common->cmnd[2]);
+		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]);
 
 		/*
 		 * We allow DPO (Disable Page Out = don't save data in the
@@ -747,7 +750,7 @@  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;
@@ -771,7 +774,10 @@  static int do_write(struct fsg_common *common)
 	if (common->cmnd[0] == WRITE_6)
 		lba = get_unaligned_be24(&common->cmnd[1]);
 	else {
-		lba = get_unaligned_be32(&common->cmnd[2]);
+		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]);
 
 		/*
 		 * We allow DPO (Disable Page Out = don't save data in the
@@ -1146,6 +1152,7 @@  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)) {
@@ -1153,12 +1160,37 @@  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 */
-	put_unaligned_be32(curlun->blksize, &buf[4]);/* Block length */
+	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;
@@ -1905,6 +1937,17 @@  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,
@@ -1957,6 +2000,25 @@  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,
@@ -2028,6 +2090,17 @@  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