diff mbox series

[02/26] sd: move zone limits setup out of sd_read_block_characteristics

Message ID 20240611051929.513387-3-hch@lst.de (mailing list archive)
State Not Applicable
Headers show
Series [01/26] sd: fix sd_is_zoned | expand

Commit Message

Christoph Hellwig June 11, 2024, 5:19 a.m. UTC
Move a bit of code that sets up the zone flag and the write granularity
into sd_zbc_read_zones to be with the rest of the zoned limits.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 drivers/scsi/sd.c     | 21 +--------------------
 drivers/scsi/sd_zbc.c | 13 ++++++++++++-
 2 files changed, 13 insertions(+), 21 deletions(-)

Comments

Damien Le Moal June 11, 2024, 5:51 a.m. UTC | #1
On 6/11/24 2:19 PM, Christoph Hellwig wrote:
> Move a bit of code that sets up the zone flag and the write granularity
> into sd_zbc_read_zones to be with the rest of the zoned limits.
> 
> Signed-off-by: Christoph Hellwig <hch@lst.de>
> ---
>  drivers/scsi/sd.c     | 21 +--------------------
>  drivers/scsi/sd_zbc.c | 13 ++++++++++++-
>  2 files changed, 13 insertions(+), 21 deletions(-)
> 
> diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
> index 85b45345a27739..5bfed61c70db8f 100644
> --- a/drivers/scsi/sd.c
> +++ b/drivers/scsi/sd.c
> @@ -3308,29 +3308,10 @@ static void sd_read_block_characteristics(struct scsi_disk *sdkp,
>  		blk_queue_flag_clear(QUEUE_FLAG_ADD_RANDOM, q);
>  	}
>  
> -
> -#ifdef CONFIG_BLK_DEV_ZONED /* sd_probe rejects ZBD devices early otherwise */
> -	if (sdkp->device->type == TYPE_ZBC) {
> -		lim->zoned = true;
> -
> -		/*
> -		 * Per ZBC and ZAC specifications, writes in sequential write
> -		 * required zones of host-managed devices must be aligned to
> -		 * the device physical block size.
> -		 */
> -		lim->zone_write_granularity = sdkp->physical_block_size;
> -	} else {
> -		/*
> -		 * Host-aware devices are treated as conventional.
> -		 */
> -		lim->zoned = false;
> -	}
> -#endif /* CONFIG_BLK_DEV_ZONED */
> -
>  	if (!sdkp->first_scan)
>  		return;
>  
> -	if (lim->zoned)
> +	if (sdkp->device->type == TYPE_ZBC)

Nit: use sd_is_zoned() here ?

>  		sd_printk(KERN_NOTICE, sdkp, "Host-managed zoned block device\n");
>  	else if (sdkp->zoned == 1)
>  		sd_printk(KERN_NOTICE, sdkp, "Host-aware SMR disk used as regular disk\n");
> diff --git a/drivers/scsi/sd_zbc.c b/drivers/scsi/sd_zbc.c
> index 422eaed8457227..e9501db0450be3 100644
> --- a/drivers/scsi/sd_zbc.c
> +++ b/drivers/scsi/sd_zbc.c
> @@ -598,8 +598,19 @@ int sd_zbc_read_zones(struct scsi_disk *sdkp, struct queue_limits *lim,
>  	u32 zone_blocks = 0;
>  	int ret;
>  
> -	if (!sd_is_zoned(sdkp))
> +	if (!sd_is_zoned(sdkp)) {
> +		lim->zoned = false;

Maybe we should clear the other zone related limits here ? If the drive is
reformatted/converted from SMR to CMR (FORMAT WITH PRESET), the other zone
limits may be set already, no ?

>  		return 0;
> +	}
> +
> +	lim->zoned = true;
> +
> +	/*
> +	 * Per ZBC and ZAC specifications, writes in sequential write required
> +	 * zones of host-managed devices must be aligned to the device physical
> +	 * block size.
> +	 */
> +	lim->zone_write_granularity = sdkp->physical_block_size;
>  
>  	/* READ16/WRITE16/SYNC16 is mandatory for ZBC devices */
>  	sdkp->device->use_16_for_rw = 1;
Christoph Hellwig June 11, 2024, 5:52 a.m. UTC | #2
On Tue, Jun 11, 2024 at 02:51:24PM +0900, Damien Le Moal wrote:
> > -	if (lim->zoned)
> > +	if (sdkp->device->type == TYPE_ZBC)
> 
> Nit: use sd_is_zoned() here ?

Yes.

> > -	if (!sd_is_zoned(sdkp))
> > +	if (!sd_is_zoned(sdkp)) {
> > +		lim->zoned = false;
> 
> Maybe we should clear the other zone related limits here ? If the drive is
> reformatted/converted from SMR to CMR (FORMAT WITH PRESET), the other zone
> limits may be set already, no ?

blk_validate_zoned_limits already takes care of that.
Christoph Hellwig June 11, 2024, 5:54 a.m. UTC | #3
On Tue, Jun 11, 2024 at 07:52:39AM +0200, Christoph Hellwig wrote:
> > Maybe we should clear the other zone related limits here ? If the drive is
> > reformatted/converted from SMR to CMR (FORMAT WITH PRESET), the other zone
> > limits may be set already, no ?
> 
> blk_validate_zoned_limits already takes care of that.

Sorry, brainfart.  The integrity code does that, but not the zoned
code.  I suspect the core code might be a better place for it,
though.
Damien Le Moal June 11, 2024, 7:20 a.m. UTC | #4
On 6/11/24 2:52 PM, Christoph Hellwig wrote:
> On Tue, Jun 11, 2024 at 02:51:24PM +0900, Damien Le Moal wrote:
>>> -	if (lim->zoned)
>>> +	if (sdkp->device->type == TYPE_ZBC)
>>
>> Nit: use sd_is_zoned() here ?
> 
> Yes.
> 
>>> -	if (!sd_is_zoned(sdkp))
>>> +	if (!sd_is_zoned(sdkp)) {
>>> +		lim->zoned = false;
>>
>> Maybe we should clear the other zone related limits here ? If the drive is
>> reformatted/converted from SMR to CMR (FORMAT WITH PRESET), the other zone
>> limits may be set already, no ?
> 
> blk_validate_zoned_limits already takes care of that.

I do not think it does:

static int blk_validate_zoned_limits(struct queue_limits *lim)
{
        if (!lim->zoned) {
                if (WARN_ON_ONCE(lim->max_open_zones) ||
                    WARN_ON_ONCE(lim->max_active_zones) ||
                    WARN_ON_ONCE(lim->zone_write_granularity) ||
                    WARN_ON_ONCE(lim->max_zone_append_sectors))
                        return -EINVAL;
                return 0;
        }
	...

So setting lim->zoned to false without clearing the other limits potentially
will trigger warnings...
Damien Le Moal June 11, 2024, 7:25 a.m. UTC | #5
On 6/11/24 2:54 PM, Christoph Hellwig wrote:
> On Tue, Jun 11, 2024 at 07:52:39AM +0200, Christoph Hellwig wrote:
>>> Maybe we should clear the other zone related limits here ? If the drive is
>>> reformatted/converted from SMR to CMR (FORMAT WITH PRESET), the other zone
>>> limits may be set already, no ?
>>
>> blk_validate_zoned_limits already takes care of that.
> 
> Sorry, brainfart.  The integrity code does that, but not the zoned
> code.  I suspect the core code might be a better place for it,
> though.

Yes. Just replied to your previous email before seeing this one.
I think that:

static int blk_validate_zoned_limits(struct queue_limits *lim)
{
        if (!lim->zoned) {
                if (WARN_ON_ONCE(lim->max_open_zones) ||
                    WARN_ON_ONCE(lim->max_active_zones) ||
                    WARN_ON_ONCE(lim->zone_write_granularity) ||
                    WARN_ON_ONCE(lim->max_zone_append_sectors))
                        return -EINVAL;
                return 0;
        }
	...

could be changed into:

static int blk_validate_zoned_limits(struct queue_limits *lim)
{
	if (!lim->zoned) {
                lim->max_open_zones = 0;
		lim->max_active_zones = 0;
		lim->zone_write_granularity = 0;
		lim->max_zone_append_sectors = 0
		return 0;
	}

But then we would not see "bad" drivers. Could have a small

blk_clear_zoned_limits(struct queue_limits *lim)

helper too.
Hannes Reinecke June 11, 2024, 8:12 a.m. UTC | #6
On 6/11/24 07:19, Christoph Hellwig wrote:
> Move a bit of code that sets up the zone flag and the write granularity
> into sd_zbc_read_zones to be with the rest of the zoned limits.
> 
> Signed-off-by: Christoph Hellwig <hch@lst.de>
> ---
>   drivers/scsi/sd.c     | 21 +--------------------
>   drivers/scsi/sd_zbc.c | 13 ++++++++++++-
>   2 files changed, 13 insertions(+), 21 deletions(-)
> 
> diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
> index 85b45345a27739..5bfed61c70db8f 100644
> --- a/drivers/scsi/sd.c
> +++ b/drivers/scsi/sd.c
> @@ -3308,29 +3308,10 @@ static void sd_read_block_characteristics(struct scsi_disk *sdkp,
>   		blk_queue_flag_clear(QUEUE_FLAG_ADD_RANDOM, q);
>   	}
>   
> -
> -#ifdef CONFIG_BLK_DEV_ZONED /* sd_probe rejects ZBD devices early otherwise */
> -	if (sdkp->device->type == TYPE_ZBC) {
> -		lim->zoned = true;
> -
> -		/*
> -		 * Per ZBC and ZAC specifications, writes in sequential write
> -		 * required zones of host-managed devices must be aligned to
> -		 * the device physical block size.
> -		 */
> -		lim->zone_write_granularity = sdkp->physical_block_size;
> -	} else {
> -		/*
> -		 * Host-aware devices are treated as conventional.
> -		 */
> -		lim->zoned = false;
> -	}
> -#endif /* CONFIG_BLK_DEV_ZONED */
> -
>   	if (!sdkp->first_scan)
>   		return;
>   
> -	if (lim->zoned)
> +	if (sdkp->device->type == TYPE_ZBC)

Why not sd_is_zoned()?

Cheers,

Hannes
Christoph Hellwig June 12, 2024, 4:45 a.m. UTC | #7
On Tue, Jun 11, 2024 at 02:51:24PM +0900, Damien Le Moal wrote:
> > -	if (!sd_is_zoned(sdkp))
> > +	if (!sd_is_zoned(sdkp)) {
> > +		lim->zoned = false;
> 
> Maybe we should clear the other zone related limits here ? If the drive is
> reformatted/converted from SMR to CMR (FORMAT WITH PRESET), the other zone
> limits may be set already, no ?

Yes, but we would not end up here.  The device type is constant over
the struct of the scsi_device and we'd have to fully reprobe it.

So we don't need to clear any flags, including the actual zoned flag
here.
Christoph Hellwig June 13, 2024, 9:39 a.m. UTC | #8
On Tue, Jun 11, 2024 at 02:51:24PM +0900, Damien Le Moal wrote:
> > +	if (sdkp->device->type == TYPE_ZBC)
> 
> Nit: use sd_is_zoned() here ?

Actually - is there much in even keeping sd_is_zoned now that the
host aware support is removed?  Just open coding the type check isn't
any more code, and probably easier to follow.
Damien Le Moal June 16, 2024, 11:01 p.m. UTC | #9
On 6/13/24 18:39, Christoph Hellwig wrote:
> On Tue, Jun 11, 2024 at 02:51:24PM +0900, Damien Le Moal wrote:
>>> +	if (sdkp->device->type == TYPE_ZBC)
>>
>> Nit: use sd_is_zoned() here ?
> 
> Actually - is there much in even keeping sd_is_zoned now that the
> host aware support is removed?  Just open coding the type check isn't
> any more code, and probably easier to follow.

Removing this helper is fine by me. There are only 2 call sites in sd.c and the
some of 4 calls in sd_zbc.c are not really needed:
1) The call in sd_zbc_print_zones() is not needed at all since this function is
called only for a zoned drive from sd_zbc_revalidate_zones().
2) The calls in sd_zbc_report_zones() and sd_zbc_cmnd_checks() are probably
useless as these are called only for zoned drives in the first place. The checks
would be useful only for passthrough commands, but then we do not really care
about these and the user will get a failure anyway if it tries to do ZBC
commands on non-ZBC drives.
3) That leaves only the call in sd_zbc_read_zones() but that check can probably
be moved to sd.c to conditionally call  sd_zbc_read_zones().
Christoph Hellwig June 17, 2024, 4:53 a.m. UTC | #10
On Mon, Jun 17, 2024 at 08:01:04AM +0900, Damien Le Moal wrote:
> On 6/13/24 18:39, Christoph Hellwig wrote:
> > On Tue, Jun 11, 2024 at 02:51:24PM +0900, Damien Le Moal wrote:
> >>> +	if (sdkp->device->type == TYPE_ZBC)
> >>
> >> Nit: use sd_is_zoned() here ?
> > 
> > Actually - is there much in even keeping sd_is_zoned now that the
> > host aware support is removed?  Just open coding the type check isn't
> > any more code, and probably easier to follow.
> 
> Removing this helper is fine by me.

FYI, I've removed it yesterday, but not done much of the cleanups suggest
here.  We should probably do those in a follow up up, uncluding removing
the !ZBC check in sd_zbc_check_zoned_characteristics.
Damien Le Moal June 17, 2024, 6:03 a.m. UTC | #11
On 6/17/24 13:53, Christoph Hellwig wrote:
> On Mon, Jun 17, 2024 at 08:01:04AM +0900, Damien Le Moal wrote:
>> On 6/13/24 18:39, Christoph Hellwig wrote:
>>> On Tue, Jun 11, 2024 at 02:51:24PM +0900, Damien Le Moal wrote:
>>>>> +	if (sdkp->device->type == TYPE_ZBC)
>>>>
>>>> Nit: use sd_is_zoned() here ?
>>>
>>> Actually - is there much in even keeping sd_is_zoned now that the
>>> host aware support is removed?  Just open coding the type check isn't
>>> any more code, and probably easier to follow.
>>
>> Removing this helper is fine by me.
> 
> FYI, I've removed it yesterday, but not done much of the cleanups suggest
> here.  We should probably do those in a follow up up, uncluding removing
> the !ZBC check in sd_zbc_check_zoned_characteristics.

OK. I will send that once your series in queued.
diff mbox series

Patch

diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index 85b45345a27739..5bfed61c70db8f 100644
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -3308,29 +3308,10 @@  static void sd_read_block_characteristics(struct scsi_disk *sdkp,
 		blk_queue_flag_clear(QUEUE_FLAG_ADD_RANDOM, q);
 	}
 
-
-#ifdef CONFIG_BLK_DEV_ZONED /* sd_probe rejects ZBD devices early otherwise */
-	if (sdkp->device->type == TYPE_ZBC) {
-		lim->zoned = true;
-
-		/*
-		 * Per ZBC and ZAC specifications, writes in sequential write
-		 * required zones of host-managed devices must be aligned to
-		 * the device physical block size.
-		 */
-		lim->zone_write_granularity = sdkp->physical_block_size;
-	} else {
-		/*
-		 * Host-aware devices are treated as conventional.
-		 */
-		lim->zoned = false;
-	}
-#endif /* CONFIG_BLK_DEV_ZONED */
-
 	if (!sdkp->first_scan)
 		return;
 
-	if (lim->zoned)
+	if (sdkp->device->type == TYPE_ZBC)
 		sd_printk(KERN_NOTICE, sdkp, "Host-managed zoned block device\n");
 	else if (sdkp->zoned == 1)
 		sd_printk(KERN_NOTICE, sdkp, "Host-aware SMR disk used as regular disk\n");
diff --git a/drivers/scsi/sd_zbc.c b/drivers/scsi/sd_zbc.c
index 422eaed8457227..e9501db0450be3 100644
--- a/drivers/scsi/sd_zbc.c
+++ b/drivers/scsi/sd_zbc.c
@@ -598,8 +598,19 @@  int sd_zbc_read_zones(struct scsi_disk *sdkp, struct queue_limits *lim,
 	u32 zone_blocks = 0;
 	int ret;
 
-	if (!sd_is_zoned(sdkp))
+	if (!sd_is_zoned(sdkp)) {
+		lim->zoned = false;
 		return 0;
+	}
+
+	lim->zoned = true;
+
+	/*
+	 * Per ZBC and ZAC specifications, writes in sequential write required
+	 * zones of host-managed devices must be aligned to the device physical
+	 * block size.
+	 */
+	lim->zone_write_granularity = sdkp->physical_block_size;
 
 	/* READ16/WRITE16/SYNC16 is mandatory for ZBC devices */
 	sdkp->device->use_16_for_rw = 1;