Fix non-printable characters in NVMe model and serial numbers.

The NVMe 1.4 spec simply says that Model and Serial numbers are
ASCII strings.  Unlike SCSI, it doesn't prohibit non-printable
characters or say that the strings should be padded with spaces.

Since 2014, we have had cam_strvis_sbuf(), which gives additional
options for handling non-ASCII characters.  That behavior hasn't
been available for non-sbuf consumers, so users of cam_strvis()
were left with having octal ASCII codes inserted.

So, to avoid having garbage or octal chracters in the strings, use
cam_strvis_sbuf() to create a new function, cam_strvis_flag(), and
re-implement cam_strvis() using cam_strvis_flag().

Now, for the NVMe drives, we can use cam_strvis_flag with the
CAM_STRVIS_FLAG_NONASCII_SPC flag.  This transforms non-printable
characters into spaces.

sys/cam/cam.c:
	Add a new function, cam_strvis_flag(), that creates an sbuf
	on the stack with the user's destination buffer, and calls
	cam_strvis_sbuf() with the given flag argument.

	Re-implement cam_strvis() to call cam_strvis_flag with the
	CAM_STRVIS_FLAG_NONASCII_ESC argument.  This should be the
	equivalent of the old cam_strvis() function, except for the
	overhead of creating the sbuf and calling sbuf_putc/printf.

sys/cam/cam.h:
	Declaration for cam_strvis_flag.

sys/cam/nvme/nvme_all.c:
	In nvme_print_ident, use the NONASCII_SPC flag with
	cam_strvis_flag().

sys/cam/nvme/nvme_da.c:
	In ndaregister(), use cam_strvis_flag() with the
	NONASCII_SPC flag for the disk description and serial
	number we report to GEOM.

sys/cam/nvme/nvme_xpt.c:
	In nvme_probe_done(), use cam_strvis_flag with the
	NONASCII_SPC flag when storing the drive serial number
	in the CAM EDT.

MFC after:	1 week
Sponsored by:	Spectra Logic
Differential Revision:	https://reviews.freebsd.org/D33973

1 files changed, 6 insertions, 4 deletions

diff --git a/sys/cam/nvme/nvme_da.c b/sys/cam/nvme/nvme_da.c
index 7a489afdb993..a3d72e1017c9 100644
--- a/sys/cam/nvme/nvme_da.c
+++ b/sys/cam/nvme/nvme_da.c
@@ -930,10 +930,12 @@ ndaregister(struct cam_periph *periph, void *arg)
 	 * d_ident and d_descr are both far bigger than the length of either
 	 *  the serial or model number strings.
 	 */
-	cam_strvis(disk->d_descr, cd->mn,
-	    NVME_MODEL_NUMBER_LENGTH, sizeof(disk->d_descr));
-	cam_strvis(disk->d_ident, cd->sn,
-	    NVME_SERIAL_NUMBER_LENGTH, sizeof(disk->d_ident));
+	cam_strvis_flag(disk->d_descr, cd->mn, NVME_MODEL_NUMBER_LENGTH,
+	    sizeof(disk->d_descr), CAM_STRVIS_FLAG_NONASCII_SPC);
+
+	cam_strvis_flag(disk->d_ident, cd->sn, NVME_SERIAL_NUMBER_LENGTH,
+	    sizeof(disk->d_ident), CAM_STRVIS_FLAG_NONASCII_SPC);
+
 	disk->d_hba_vendor = cpi.hba_vendor;
 	disk->d_hba_device = cpi.hba_device;
 	disk->d_hba_subvendor = cpi.hba_subvendor;