[PATCH v9 0/6] Improve libata support for FUA

[PATCH v9 0/6] Improve libata support for FUA

[Damien Le Moal]

These patches cleanup and improve libata support for ATA devices
supporting the FUA feature.

The first patch modifies the block layer to prevent the use of REQ_FUA
with read requests. This is necessary as the block layer code expect
REQ_FUA to be used with write requests (the flush machinery cannot
enforce access to the media for FUA read commands) and FUA is not
supported with ATA devices when NCQ is not enabled (device queue depth
set to 1).

Patch 2 and 3 are libata cleanup preparatory patches. Patch 4 cleans up
the detection for FUA support. Patch 5 fixes building a taskfile for FUA
write requests. Patch 6 prevents the use of FUA with known bad drives.

Changes from v8:
 - Added Niklas Review tag to patch 1 (forgot to do that when I sent
   v8).

Changes from v7:
 - Given that there are concerns about introducing regressions with
   older devices by enabling FUA by default, patch 7 is dropped for now.
   A more restrictive approach enabling FUA by default only for very
   recent drives will be sent later.

Changes from v6:
 - Modified patch 1 to include checks for REQ_OP_ZONE_APPEND
 - Addressed comments from Niklas (patch 2 -> return false, patch 3 ->
   commit message typo, patch 7 -> more verbose commit message)

Changes from v5:
 - Removed WARN for FUA reads in patch 5.
 - Added reviewed-by tags.

Changes from v4:
 - Changed patch 1 to the one suggested by Christoph.
 - Added Hannes review tag.

Changes from v3:
 - Added patch 1 to prevent any block device user from issuing a
   REQ_FUA read.
 - Changed patch 5 to remove the check for REQ_FUA read and also remove 
   support for ATA_CMD_WRITE_MULTI_FUA_EXT as this command is obsolete
   in recent ACS specifications.

Changes from v2:
 - Added patch 1 and 2 as preparatory patches
 - Added patch 4 to fix FUA writes handling for the non-ncq case. Note
   that it is possible that the drives blacklisted in patch 5 are
   actually OK since the code back in 2012 had the issue with the wrong
   use of LBA 28 commands for FUA writes.

Changes from v1:
 - Removed Maciej's patch 2. Instead, blacklist drives which are known
   to have a buggy FUA support.

Christoph Hellwig (1):
  block: add a sanity check for non-write flush/fua bios

Damien Le Moal (5):
  ata: libata: Introduce ata_ncq_supported()
  ata: libata: Rename and cleanup ata_rwcmd_protocol()
  ata: libata: cleanup fua support detection
  ata: libata: Fix FUA handling in ata_build_rw_tf()
  ata: libata: blacklist FUA support for known buggy drives

 .../admin-guide/kernel-parameters.txt         |  3 +
 block/blk-core.c                              | 14 ++--
 drivers/ata/libata-core.c                     | 69 ++++++++++++++-----
 drivers/ata/libata-scsi.c                     | 30 +-------
 include/linux/libata.h                        | 36 +++++++---
 5 files changed, 92 insertions(+), 60 deletions(-)

-- 
2.39.0

[PATCH v9 1/6] block: add a sanity check for non-write flush/fua bios

[Damien Le Moal]

From: Christoph Hellwig <hch@infradead.org>

Check that the PREFUSH and FUA flags are only set on write bios,
given that the flush state machine expects that.

[Damien] The check is also extended to REQ_OP_ZONE_APPEND operations as
these are data write operations used by btrfs and zonefs and may also
have the REQ_FUA bit set.

Reported-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Reviewed-by: Niklas Cassel <niklas.cassel@wdc.com>
---
 block/blk-core.c | 14 +++++++++-----
 1 file changed, 9 insertions(+), 5 deletions(-)

diff --git a/block/blk-core.c b/block/blk-core.c
index 9321767470dc..c644aac498ef 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -744,12 +744,16 @@ void submit_bio_noacct(struct bio *bio)
 	 * Filter flush bio's early so that bio based drivers without flush
 	 * support don't have to worry about them.
 	 */
-	if (op_is_flush(bio->bi_opf) &&
-	    !test_bit(QUEUE_FLAG_WC, &q->queue_flags)) {
-		bio->bi_opf &= ~(REQ_PREFLUSH | REQ_FUA);
-		if (!bio_sectors(bio)) {
-			status = BLK_STS_OK;
+	if (op_is_flush(bio->bi_opf)) {
+		if (WARN_ON_ONCE(bio_op(bio) != REQ_OP_WRITE &&
+				 bio_op(bio) != REQ_OP_ZONE_APPEND))
 			goto end_io;
+		if (!test_bit(QUEUE_FLAG_WC, &q->queue_flags)) {
+			bio->bi_opf &= ~(REQ_PREFLUSH | REQ_FUA);
+			if (!bio_sectors(bio)) {
+				status = BLK_STS_OK;
+				goto end_io;
+			}
 		}
 	}
 
-- 
2.39.0

Re: [PATCH v9 1/6] block: add a sanity check for non-write flush/fua bios

[Damien Le Moal]

On 1/10/23 22:27, Damien Le Moal wrote:
> From: Christoph Hellwig <hch@infradead.org>
> 
> Check that the PREFUSH and FUA flags are only set on write bios,
> given that the flush state machine expects that.
> 
> [Damien] The check is also extended to REQ_OP_ZONE_APPEND operations as
> these are data write operations used by btrfs and zonefs and may also
> have the REQ_FUA bit set.
> 
> Reported-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
> Signed-off-by: Christoph Hellwig <hch@lst.de>
> Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
> Reviewed-by: Niklas Cassel <niklas.cassel@wdc.com>

Christoph, Jens,

Are you OK with this patch ?

I am going to queue up patches 2 to 6 in libata tree as we have another
series on top of these patches (CDL series rebased). Jens, if you could
take this one in the block tree, that would be great.

Thanks !

> ---
>  block/blk-core.c | 14 +++++++++-----
>  1 file changed, 9 insertions(+), 5 deletions(-)
> 
> diff --git a/block/blk-core.c b/block/blk-core.c
> index 9321767470dc..c644aac498ef 100644
> --- a/block/blk-core.c
> +++ b/block/blk-core.c
> @@ -744,12 +744,16 @@ void submit_bio_noacct(struct bio *bio)
>  	 * Filter flush bio's early so that bio based drivers without flush
>  	 * support don't have to worry about them.
>  	 */
> -	if (op_is_flush(bio->bi_opf) &&
> -	    !test_bit(QUEUE_FLAG_WC, &q->queue_flags)) {
> -		bio->bi_opf &= ~(REQ_PREFLUSH | REQ_FUA);
> -		if (!bio_sectors(bio)) {
> -			status = BLK_STS_OK;
> +	if (op_is_flush(bio->bi_opf)) {
> +		if (WARN_ON_ONCE(bio_op(bio) != REQ_OP_WRITE &&
> +				 bio_op(bio) != REQ_OP_ZONE_APPEND))
>  			goto end_io;
> +		if (!test_bit(QUEUE_FLAG_WC, &q->queue_flags)) {
> +			bio->bi_opf &= ~(REQ_PREFLUSH | REQ_FUA);
> +			if (!bio_sectors(bio)) {
> +				status = BLK_STS_OK;
> +				goto end_io;
> +			}
>  		}
>  	}
>  

-- 
Damien Le Moal
Western Digital Research

Re: [PATCH v9 1/6] block: add a sanity check for non-write flush/fua bios

[Christoph Hellwig]

Yes, I'm ok with the updates to it.

Re: [PATCH v9 1/6] block: add a sanity check for non-write flush/fua bios

[Jens Axboe]

On Jan 10, 2023, at 2:58 PM, Damien Le Moal <damien.lemoal@opensource.wdc.com> wrote:
> 
> On 1/10/23 22:27, Damien Le Moal wrote:
>> From: Christoph Hellwig <hch@infradead.org>
>> 
>> Check that the PREFUSH and FUA flags are only set on write bios,
>> given that the flush state machine expects that.
>> 
>> [Damien] The check is also extended to REQ_OP_ZONE_APPEND operations as
>> these are data write operations used by btrfs and zonefs and may also
>> have the REQ_FUA bit set.
>> 
>> Reported-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
>> Signed-off-by: Christoph Hellwig <hch@lst.de>
>> Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
>> Reviewed-by: Niklas Cassel <niklas.cassel@wdc.com>
> 
> Christoph, Jens,
> 
> Are you OK with this patch ?

I already acked a previous version, you just didn’t pick it up. 

— 
Jens Axboe

Re: [PATCH v9 1/6] block: add a sanity check for non-write flush/fua bios

[Damien Le Moal]

On 1/11/23 13:32, Jens Axboe wrote:
> On Jan 10, 2023, at 2:58 PM, Damien Le Moal <damien.lemoal@opensource.wdc.com> wrote:
>>
>> On 1/10/23 22:27, Damien Le Moal wrote:
>>> From: Christoph Hellwig <hch@infradead.org>
>>>
>>> Check that the PREFUSH and FUA flags are only set on write bios,
>>> given that the flush state machine expects that.
>>>
>>> [Damien] The check is also extended to REQ_OP_ZONE_APPEND operations as
>>> these are data write operations used by btrfs and zonefs and may also
>>> have the REQ_FUA bit set.
>>>
>>> Reported-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
>>> Signed-off-by: Christoph Hellwig <hch@lst.de>
>>> Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
>>> Reviewed-by: Niklas Cassel <niklas.cassel@wdc.com>
>>
>> Christoph, Jens,
>>
>> Are you OK with this patch ?
> 
> I already acked a previous version, you just didn’t pick it up. 

I noticed your ack. But since I changed the patch, I wanted confirmation
again. Do you want me to pickup this version through the ATA tree ?
You can take it through the block tree as the block patch can go in
separately. There are no conflicts/dependencies for compile with the ATA
part. Whichever is fine with me.

> 
> — 
> Jens Axboe
> 

-- 
Damien Le Moal
Western Digital Research

[PATCH v9 2/6] ata: libata: Introduce ata_ncq_supported()

[Damien Le Moal]

Introduce the inline helper function ata_ncq_supported() to test if a
device supports NCQ commands. The function ata_ncq_enabled() is also
rewritten using this new helper function.

Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Niklas Cassel <niklas.cassel@wdc.com>
---
 include/linux/libata.h | 28 +++++++++++++++++++++-------
 1 file changed, 21 insertions(+), 7 deletions(-)

diff --git a/include/linux/libata.h b/include/linux/libata.h
index 3b7f5d9e2f87..059ca7f2b69c 100644
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -1691,21 +1691,35 @@ extern struct ata_device *ata_dev_next(struct ata_device *dev,
 	     (dev) = ata_dev_next((dev), (link), ATA_DITER_##mode))
 
 /**
- *	ata_ncq_enabled - Test whether NCQ is enabled
- *	@dev: ATA device to test for
+ *	ata_ncq_supported - Test whether NCQ is supported
+ *	@dev: ATA device to test
  *
  *	LOCKING:
  *	spin_lock_irqsave(host lock)
  *
  *	RETURNS:
- *	1 if NCQ is enabled for @dev, 0 otherwise.
+ *	true if @dev supports NCQ, false otherwise.
  */
-static inline int ata_ncq_enabled(struct ata_device *dev)
+static inline bool ata_ncq_supported(struct ata_device *dev)
 {
 	if (!IS_ENABLED(CONFIG_SATA_HOST))
-		return 0;
-	return (dev->flags & (ATA_DFLAG_PIO | ATA_DFLAG_NCQ_OFF |
-			      ATA_DFLAG_NCQ)) == ATA_DFLAG_NCQ;
+		return false;
+	return (dev->flags & (ATA_DFLAG_PIO | ATA_DFLAG_NCQ)) == ATA_DFLAG_NCQ;
+}
+
+/**
+ *	ata_ncq_enabled - Test whether NCQ is enabled
+ *	@dev: ATA device to test
+ *
+ *	LOCKING:
+ *	spin_lock_irqsave(host lock)
+ *
+ *	RETURNS:
+ *	true if NCQ is enabled for @dev, false otherwise.
+ */
+static inline bool ata_ncq_enabled(struct ata_device *dev)
+{
+	return ata_ncq_supported(dev) && !(dev->flags & ATA_DFLAG_NCQ_OFF);
 }
 
 static inline bool ata_fpdma_dsm_supported(struct ata_device *dev)
-- 
2.39.0

[PATCH v9 3/6] ata: libata: Rename and cleanup ata_rwcmd_protocol()

[Damien Le Moal]

Rename ata_rwcmd_protocol() to ata_set_rwcmd_protocol() to better
reflect the fact that this function sets a task file command and
protocol. The arguments order is also reversed and the function return
type changed to a bool to indicate if the command and protocol were set
correctly (instead of returning a completely arbitrary "-1" value.

Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Niklas Cassel <niklas.cassel@wdc.com>
---
 drivers/ata/libata-core.c | 28 +++++++++++++++-------------
 1 file changed, 15 insertions(+), 13 deletions(-)

diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index 6b03bebcde50..1c16342dda08 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -574,17 +574,18 @@ static const u8 ata_rw_cmds[] = {
 };
 
 /**
- *	ata_rwcmd_protocol - set taskfile r/w commands and protocol
- *	@tf: command to examine and configure
- *	@dev: device tf belongs to
+ *	ata_set_rwcmd_protocol - set taskfile r/w command and protocol
+ *	@dev: target device for the taskfile
+ *	@tf: taskfile to examine and configure
  *
- *	Examine the device configuration and tf->flags to calculate
- *	the proper read/write commands and protocol to use.
+ *	Examine the device configuration and tf->flags to determine
+ *	the proper read/write command and protocol to use for @tf.
  *
  *	LOCKING:
  *	caller.
  */
-static int ata_rwcmd_protocol(struct ata_taskfile *tf, struct ata_device *dev)
+static bool ata_set_rwcmd_protocol(struct ata_device *dev,
+				   struct ata_taskfile *tf)
 {
 	u8 cmd;
 
@@ -607,11 +608,12 @@ static int ata_rwcmd_protocol(struct ata_taskfile *tf, struct ata_device *dev)
 	}
 
 	cmd = ata_rw_cmds[index + fua + lba48 + write];
-	if (cmd) {
-		tf->command = cmd;
-		return 0;
-	}
-	return -1;
+	if (!cmd)
+		return false;
+
+	tf->command = cmd;
+
+	return true;
 }
 
 /**
@@ -744,7 +746,7 @@ int ata_build_rw_tf(struct ata_queued_cmd *qc, u64 block, u32 n_block,
 			/* request too large even for LBA48 */
 			return -ERANGE;
 
-		if (unlikely(ata_rwcmd_protocol(tf, dev) < 0))
+		if (unlikely(!ata_set_rwcmd_protocol(dev, tf)))
 			return -EINVAL;
 
 		tf->nsect = n_block & 0xff;
@@ -762,7 +764,7 @@ int ata_build_rw_tf(struct ata_queued_cmd *qc, u64 block, u32 n_block,
 		if (!lba_28_ok(block, n_block))
 			return -ERANGE;
 
-		if (unlikely(ata_rwcmd_protocol(tf, dev) < 0))
+		if (unlikely(!ata_set_rwcmd_protocol(dev, tf)))
 			return -EINVAL;
 
 		/* Convert LBA to CHS */
-- 
2.39.0

[PATCH v9 4/6] ata: libata: cleanup fua support detection

[Damien Le Moal]

Move the detection of a device FUA support from
ata_scsiop_mode_sense()/ata_dev_supports_fua() to device scan time in
ata_dev_configure().

The function ata_dev_config_fua() is introduced to detect if a device
supports FUA and this support is indicated using the new device flag
ATA_DFLAG_FUA.

In order to blacklist known buggy devices, the horkage flag
ATA_HORKAGE_NO_FUA is introduced. Similarly to other horkage flags, the
libata.force= arguments "fua" and "nofua" are also introduced to allow
a user to control this horkage flag through the "force" libata
module parameter.

The ATA_DFLAG_FUA device flag is set only and only if all the following
conditions are met:
* libata.fua module parameter is set to 1
* The device supports the WRITE DMA FUA EXT command,
* The device is not marked with the ATA_HORKAGE_NO_FUA flag, either from
  the blacklist or set by the user with libata.force=nofua
* The device supports NCQ (while this is not mandated by the standards,
  this restriction is introduced to avoid problems with older non-NCQ
  devices).

Enabling or diabling libata FUA support for all devices can now also be
done using the "force=[no]fua" module parameter when libata.fua is set
to 1.

Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Niklas Cassel <niklas.cassel@wdc.com>
---
 .../admin-guide/kernel-parameters.txt         |  3 ++
 drivers/ata/libata-core.c                     | 30 ++++++++++++++++++-
 drivers/ata/libata-scsi.c                     | 30 ++-----------------
 include/linux/libata.h                        |  8 +++--
 4 files changed, 39 insertions(+), 32 deletions(-)

diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 6cfa6e3996cf..3d0f2de7dc03 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -2816,6 +2816,9 @@
 			* [no]setxfer: Indicate if transfer speed mode setting
 			  should be skipped.
 
+			* [no]fua: Disable or enable FUA (Force Unit Access)
+			  support for devices supporting this feature.
+
 			* dump_id: Dump IDENTIFY data.
 
 			* disable: Disable this device.
diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index 1c16342dda08..d25a53a873dc 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -2422,6 +2422,28 @@ static void ata_dev_config_chs(struct ata_device *dev)
 			     dev->heads, dev->sectors);
 }
 
+static void ata_dev_config_fua(struct ata_device *dev)
+{
+	/* Ignore FUA support if its use is disabled globally */
+	if (!libata_fua)
+		goto nofua;
+
+	/* Ignore devices without support for WRITE DMA FUA EXT */
+	if (!(dev->flags & ATA_DFLAG_LBA48) || !ata_id_has_fua(dev->id))
+		goto nofua;
+
+	/* Ignore known bad devices and devices that lack NCQ support */
+	if (!ata_ncq_supported(dev) || (dev->horkage & ATA_HORKAGE_NO_FUA))
+		goto nofua;
+
+	dev->flags |= ATA_DFLAG_FUA;
+
+	return;
+
+nofua:
+	dev->flags &= ~ATA_DFLAG_FUA;
+}
+
 static void ata_dev_config_devslp(struct ata_device *dev)
 {
 	u8 *sata_setting = dev->link->ap->sector_buf;
@@ -2510,7 +2532,8 @@ static void ata_dev_print_features(struct ata_device *dev)
 		return;
 
 	ata_dev_info(dev,
-		     "Features:%s%s%s%s%s%s\n",
+		     "Features:%s%s%s%s%s%s%s\n",
+		     dev->flags & ATA_DFLAG_FUA ? " FUA" : "",
 		     dev->flags & ATA_DFLAG_TRUSTED ? " Trust" : "",
 		     dev->flags & ATA_DFLAG_DA ? " Dev-Attention" : "",
 		     dev->flags & ATA_DFLAG_DEVSLP ? " Dev-Sleep" : "",
@@ -2671,6 +2694,7 @@ int ata_dev_configure(struct ata_device *dev)
 			ata_dev_config_chs(dev);
 		}
 
+		ata_dev_config_fua(dev);
 		ata_dev_config_devslp(dev);
 		ata_dev_config_sense_reporting(dev);
 		ata_dev_config_zac(dev);
@@ -4105,6 +4129,9 @@ static const struct ata_blacklist_entry ata_device_blacklist [] = {
 	 */
 	{ "SATADOM-ML 3ME",		NULL,	ATA_HORKAGE_NO_LOG_DIR },
 
+	/* Buggy FUA */
+	{ "Maxtor",		"BANC1G10",	ATA_HORKAGE_NO_FUA },
+
 	/* End Marker */
 	{ }
 };
@@ -6216,6 +6243,7 @@ static const struct ata_force_param force_tbl[] __initconst = {
 	force_horkage_onoff(lpm,	ATA_HORKAGE_NOLPM),
 	force_horkage_onoff(setxfer,	ATA_HORKAGE_NOSETXFER),
 	force_horkage_on(dump_id,	ATA_HORKAGE_DUMP_ID),
+	force_horkage_onoff(fua,	ATA_HORKAGE_NO_FUA),
 
 	force_horkage_on(disable,	ATA_HORKAGE_DISABLE),
 };
diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c
index 46109bde8a04..aa338f10cef2 100644
--- a/drivers/ata/libata-scsi.c
+++ b/drivers/ata/libata-scsi.c
@@ -2240,30 +2240,6 @@ static unsigned int ata_msense_rw_recovery(u8 *buf, bool changeable)
 	return sizeof(def_rw_recovery_mpage);
 }
 
-/*
- * We can turn this into a real blacklist if it's needed, for now just
- * blacklist any Maxtor BANC1G10 revision firmware
- */
-static int ata_dev_supports_fua(u16 *id)
-{
-	unsigned char model[ATA_ID_PROD_LEN + 1], fw[ATA_ID_FW_REV_LEN + 1];
-
-	if (!libata_fua)
-		return 0;
-	if (!ata_id_has_fua(id))
-		return 0;
-
-	ata_id_c_string(id, model, ATA_ID_PROD, sizeof(model));
-	ata_id_c_string(id, fw, ATA_ID_FW_REV, sizeof(fw));
-
-	if (strcmp(model, "Maxtor"))
-		return 1;
-	if (strcmp(fw, "BANC1G10"))
-		return 1;
-
-	return 0; /* blacklisted */
-}
-
 /**
  *	ata_scsiop_mode_sense - Simulate MODE SENSE 6, 10 commands
  *	@args: device IDENTIFY data / SCSI command of interest.
@@ -2287,7 +2263,7 @@ static unsigned int ata_scsiop_mode_sense(struct ata_scsi_args *args, u8 *rbuf)
 	};
 	u8 pg, spg;
 	unsigned int ebd, page_control, six_byte;
-	u8 dpofua, bp = 0xff;
+	u8 dpofua = 0, bp = 0xff;
 	u16 fp;
 
 	six_byte = (scsicmd[0] == MODE_SENSE);
@@ -2350,9 +2326,7 @@ static unsigned int ata_scsiop_mode_sense(struct ata_scsi_args *args, u8 *rbuf)
 		goto invalid_fld;
 	}
 
-	dpofua = 0;
-	if (ata_dev_supports_fua(args->id) && (dev->flags & ATA_DFLAG_LBA48) &&
-	    (!(dev->flags & ATA_DFLAG_PIO) || dev->multi_count))
+	if (dev->flags & ATA_DFLAG_FUA)
 		dpofua = 1 << 4;
 
 	if (six_byte) {
diff --git a/include/linux/libata.h b/include/linux/libata.h
index 059ca7f2b69c..a759dfbdcc91 100644
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -90,6 +90,7 @@ enum {
 	ATA_DFLAG_ACPI_FAILED	= (1 << 6), /* ACPI on devcfg has failed */
 	ATA_DFLAG_AN		= (1 << 7), /* AN configured */
 	ATA_DFLAG_TRUSTED	= (1 << 8), /* device supports trusted send/recv */
+	ATA_DFLAG_FUA		= (1 << 9), /* device supports FUA */
 	ATA_DFLAG_DMADIR	= (1 << 10), /* device requires DMADIR */
 	ATA_DFLAG_NCQ_SEND_RECV = (1 << 11), /* device supports NCQ SEND and RECV */
 	ATA_DFLAG_NCQ_PRIO	= (1 << 12), /* device supports NCQ priority */
@@ -112,9 +113,9 @@ enum {
 	ATA_DFLAG_D_SENSE	= (1 << 29), /* Descriptor sense requested */
 	ATA_DFLAG_ZAC		= (1 << 30), /* ZAC device */
 
-	ATA_DFLAG_FEATURES_MASK	= ATA_DFLAG_TRUSTED | ATA_DFLAG_DA | \
-				  ATA_DFLAG_DEVSLP | ATA_DFLAG_NCQ_SEND_RECV | \
-				  ATA_DFLAG_NCQ_PRIO,
+	ATA_DFLAG_FEATURES_MASK	= (ATA_DFLAG_TRUSTED | ATA_DFLAG_DA |	\
+				   ATA_DFLAG_DEVSLP | ATA_DFLAG_NCQ_SEND_RECV | \
+				   ATA_DFLAG_NCQ_PRIO | ATA_DFLAG_FUA),
 
 	ATA_DEV_UNKNOWN		= 0,	/* unknown device */
 	ATA_DEV_ATA		= 1,	/* ATA device */
@@ -381,6 +382,7 @@ enum {
 	ATA_HORKAGE_NO_NCQ_ON_ATI = (1 << 27),	/* Disable NCQ on ATI chipset */
 	ATA_HORKAGE_NO_ID_DEV_LOG = (1 << 28),	/* Identify device log missing */
 	ATA_HORKAGE_NO_LOG_DIR	= (1 << 29),	/* Do not read log directory */
+	ATA_HORKAGE_NO_FUA	= (1 << 30),	/* Do not use FUA */
 
 	 /* DMA mask for user DMA control: User visible values; DO NOT
 	    renumber */
-- 
2.39.0

[PATCH v9 5/6] ata: libata: Fix FUA handling in ata_build_rw_tf()

[Damien Le Moal]

If a user issues a write command with the FUA bit set for a device with
NCQ support disabled (that is, the device queue depth was set to 1), the
LBA 48 command WRITE DMA FUA EXT must be used. However,
ata_build_rw_tf() ignores this and first tests if LBA 28 can be used
based on the write command sector and number of blocks. That is, for
small FUA writes at low LBAs, ata_rwcmd_protocol() will cause the write
to fail.

Fix this by preventing the use of LBA 28 for any FUA write request.

Given that the WRITE MULTI FUA EXT command is marked as obsolete in the
ATA specification since ACS-3 (published in 2013), remove the
ATA_CMD_WRITE_MULTI_FUA_EXT command from the ata_rw_cmds array.

Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Niklas Cassel <niklas.cassel@wdc.com>
---
 drivers/ata/libata-core.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index d25a53a873dc..ac88376f095a 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -552,7 +552,7 @@ static const u8 ata_rw_cmds[] = {
 	0,
 	0,
 	0,
-	ATA_CMD_WRITE_MULTI_FUA_EXT,
+	0,
 	/* pio */
 	ATA_CMD_PIO_READ,
 	ATA_CMD_PIO_WRITE,
@@ -727,7 +727,8 @@ int ata_build_rw_tf(struct ata_queued_cmd *qc, u64 block, u32 n_block,
 	} else if (dev->flags & ATA_DFLAG_LBA) {
 		tf->flags |= ATA_TFLAG_LBA;
 
-		if (lba_28_ok(block, n_block)) {
+		/* We need LBA48 for FUA writes */
+		if (!(tf->flags & ATA_TFLAG_FUA) && lba_28_ok(block, n_block)) {
 			/* use LBA28 */
 			tf->device |= (block >> 24) & 0xf;
 		} else if (lba_48_ok(block, n_block)) {
@@ -742,9 +743,10 @@ int ata_build_rw_tf(struct ata_queued_cmd *qc, u64 block, u32 n_block,
 			tf->hob_lbah = (block >> 40) & 0xff;
 			tf->hob_lbam = (block >> 32) & 0xff;
 			tf->hob_lbal = (block >> 24) & 0xff;
-		} else
+		} else {
 			/* request too large even for LBA48 */
 			return -ERANGE;
+		}
 
 		if (unlikely(!ata_set_rwcmd_protocol(dev, tf)))
 			return -EINVAL;
-- 
2.39.0

[PATCH v9 6/6] ata: libata: blacklist FUA support for known buggy drives

[Damien Le Moal]

Thread [1] reported back in 2012 problems with enabling FUA for 3
different drives. Add these drives to ata_device_blacklist[] to mark
them with the ATA_HORKAGE_NO_FUA flag. To be conservative and avoid
problems on old systems, the model number for the three new entries
are defined as to widely match all drives in the same product line.

[1]: https://lore.kernel.org/lkml/CA+6av4=uxu_q5U_46HtpUt=FSgbh3pZuAEY54J5_xK=MKWq-YQ@mail.gmail.com/

Suggested-by: Maciej S. Szmigiero <mail@maciej.szmigiero.name>
Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Maciej S. Szmigiero <maciej.szmigiero@oracle.com>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Niklas Cassel <niklas.cassel@wdc.com>
---
 drivers/ata/libata-core.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index ac88376f095a..36c1aca310e9 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -4133,6 +4133,9 @@ static const struct ata_blacklist_entry ata_device_blacklist [] = {
 
 	/* Buggy FUA */
 	{ "Maxtor",		"BANC1G10",	ATA_HORKAGE_NO_FUA },
+	{ "WDC*WD2500J*",	NULL,		ATA_HORKAGE_NO_FUA },
+	{ "OCZ-VERTEX*",	NULL,		ATA_HORKAGE_NO_FUA },
+	{ "INTEL*SSDSC2CT*",	NULL,		ATA_HORKAGE_NO_FUA },
 
 	/* End Marker */
 	{ }
-- 
2.39.0