Re: [PATCH 4/4] Move USE_WCACHING to drivers/block/pktcdvd.c

Christoph Hellwig
2023-02-20T06:20:23Z

On Fri, Feb 17, 2023 at 09:23:01PM +0100, Thomas Huth wrote:
> From: Palmer Dabbelt <palmer@dabbelt.com>
>
> I don't think this was ever intended to be exposed to userspace, but
> it did require an "#ifdef CONFIG_*". Since the name is kind of
> generic and was only used in one place, I've moved the definition to
> the one user.

I'd just remove USE_WCACHING entirel with something like:

diff --git a/drivers/block/pktcdvd.c b/drivers/block/pktcdvd.c
index 2f1a92509271c4..5ae2a80db2c341 100644
--- a/drivers/block/pktcdvd.c
+++ b/drivers/block/pktcdvd.c
@@ -1869,12 +1869,12 @@ static noinline_for_stack int pkt_probe_settings(struct pktcdvd_device *pd)
/*
* enable/disable write caching on drive
*/
-static noinline_for_stack int pkt_write_caching(struct pktcdvd_device *pd,
- int set)
+static noinline_for_stack int pkt_write_caching(struct pktcdvd_device *pd)
{
struct packet_command cgc;
struct scsi_sense_hdr sshdr;
unsigned char buf[64];
+ bool set = IS_ENABLED(CONFIG_CDROM_PKTCDVD_WCACHE);
int ret;

init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_READ);
@@ -1890,7 +1890,12 @@ static noinline_for_stack int pkt_write_caching(struct pktcdvd_device *pd,
if (ret)
return ret;

- buf[pd->mode_offset + 10] |= (!!set << 2);
+ /*
+ * use drive write caching -- we need deferred error handling to be
+ * able to successfully recover with this option (drive will return good
+ * status as soon as the cdb is validated).
+ */
+ buf[pd->mode_offset + 10] |= (set << 2);

cgc.buflen = cgc.cmd[8] = 2 + ((buf[0] << 8) | (buf[1] & 0xff));
ret = pkt_mode_select(pd, &cgc);
@@ -2085,7 +2090,7 @@ static int pkt_open_write(struct pktcdvd_device *pd)
return -EIO;
}

- pkt_write_caching(pd, USE_WCACHING);
+ pkt_write_caching(pd);

ret = pkt_get_max_speed(pd, &write_speed);
if (ret)
diff --git a/include/uapi/linux/pktcdvd.h b/include/uapi/linux/pktcdvd.h
index 9cbb55d21c94af..6a5552dfd6af4e 100644
--- a/include/uapi/linux/pktcdvd.h
+++ b/include/uapi/linux/pktcdvd.h
@@ -29,17 +29,6 @@
*/
#define PACKET_WAIT_TIME (HZ * 5 / 1000)

-/*
- * use drive write caching -- we need deferred error handling to be
- * able to successfully recover with this option (drive will return good
- * status as soon as the cdb is validated).
- */
-#if defined(CONFIG_CDROM_PKTCDVD_WCACHE)
-#define USE_WCACHING 1
-#else
-#define USE_WCACHING 0
-#endif
-
/*
* No user-servicable parts beyond this point ->
*/