mtip32xx: fixes and cleanups

mtip32xx: fixes and cleanups

[Christoph Hellwig]

Various low hanging fruit, kicked of by seeing one of the few remaining
req->special users.

Compile tested only.

[PATCH 1/9] mtip32xx: move the blk_rq_map_sg call to mtip_hw_submit_io

[Christoph Hellwig]

We have all arguments at hand in mtip_hw_submit_io, so keep the
rq to sg mapping close to the dma_map_sg call.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 drivers/block/mtip32xx/mtip32xx.c | 11 ++++-------
 1 file changed, 4 insertions(+), 7 deletions(-)

diff --git a/drivers/block/mtip32xx/mtip32xx.c b/drivers/block/mtip32xx/mtip32xx.c
index 947aa10107a6..1964af8a187b 100644
--- a/drivers/block/mtip32xx/mtip32xx.c
+++ b/drivers/block/mtip32xx/mtip32xx.c
@@ -2171,7 +2171,6 @@ static int mtip_hw_ioctl(struct driver_data *dd, unsigned int cmd,
  * @dd       Pointer to the driver data structure.
  * @start    First sector to read.
  * @nsect    Number of sectors to read.
- * @nents    Number of entries in scatter list for the read command.
  * @tag      The tag of this read command.
  * @callback Pointer to the function that should be called
  *	     when the read completes.
@@ -2183,7 +2182,7 @@ static int mtip_hw_ioctl(struct driver_data *dd, unsigned int cmd,
  *	None
  */
 static void mtip_hw_submit_io(struct driver_data *dd, struct request *rq,
-			      struct mtip_cmd *command, int nents,
+			      struct mtip_cmd *command,
 			      struct blk_mq_hw_ctx *hctx)
 {
 	struct host_to_dev_fis	*fis;
@@ -2191,8 +2190,10 @@ static void mtip_hw_submit_io(struct driver_data *dd, struct request *rq,
 	int dma_dir = rq_data_dir(rq) == READ ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
 	u64 start = blk_rq_pos(rq);
 	unsigned int nsect = blk_rq_sectors(rq);
+	unsigned int nents;
 
 	/* Map the scatter list for DMA access */
+	nents = blk_rq_map_sg(hctx->queue, rq, command->sg);
 	nents = dma_map_sg(&dd->pdev->dev, command->sg, nents, dma_dir);
 
 	prefetch(&port->flags);
@@ -3548,7 +3549,6 @@ static int mtip_submit_request(struct blk_mq_hw_ctx *hctx, struct request *rq)
 {
 	struct driver_data *dd = hctx->queue->queuedata;
 	struct mtip_cmd *cmd = blk_mq_rq_to_pdu(rq);
-	unsigned int nents;
 
 	if (is_se_active(dd))
 		return -ENODATA;
@@ -3579,11 +3579,8 @@ static int mtip_submit_request(struct blk_mq_hw_ctx *hctx, struct request *rq)
 		return 0;
 	}
 
-	/* Create the scatter list for this request. */
-	nents = blk_rq_map_sg(hctx->queue, rq, cmd->sg);
-
 	/* Issue the read/write. */
-	mtip_hw_submit_io(dd, rq, cmd, nents, hctx);
+	mtip_hw_submit_io(dd, rq, cmd, hctx);
 	return 0;
 }
 
-- 
2.19.1

[PATCH 2/9] mtip32xx: merge mtip_submit_request into mtip_queue_rq

[Christoph Hellwig]

Factor out a new is_stopped helper that matches the existing
is_se_active helper, and merge the trivial amount of remaining code
into the only caller.  This also allows better error handling by
returning a BLK_STS_* directly instead of explicitly calling
blk_mq_end_request, and moving blk_mq_start_request closer to the
actual issue to hardware.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 drivers/block/mtip32xx/mtip32xx.c | 78 +++++++++++--------------------
 1 file changed, 28 insertions(+), 50 deletions(-)

diff --git a/drivers/block/mtip32xx/mtip32xx.c b/drivers/block/mtip32xx/mtip32xx.c
index 1964af8a187b..75a4ca0210f2 100644
--- a/drivers/block/mtip32xx/mtip32xx.c
+++ b/drivers/block/mtip32xx/mtip32xx.c
@@ -3534,54 +3534,24 @@ static inline bool is_se_active(struct driver_data *dd)
 	return false;
 }
 
-/*
- * Block layer make request function.
- *
- * This function is called by the kernel to process a BIO for
- * the P320 device.
- *
- * @queue Pointer to the request queue. Unused other than to obtain
- *              the driver data structure.
- * @rq    Pointer to the request.
- *
- */
-static int mtip_submit_request(struct blk_mq_hw_ctx *hctx, struct request *rq)
+static inline bool is_stopped(struct driver_data *dd, struct request *rq)
 {
-	struct driver_data *dd = hctx->queue->queuedata;
-	struct mtip_cmd *cmd = blk_mq_rq_to_pdu(rq);
-
-	if (is_se_active(dd))
-		return -ENODATA;
-
-	if (unlikely(dd->dd_flag & MTIP_DDF_STOP_IO)) {
-		if (unlikely(test_bit(MTIP_DDF_REMOVE_PENDING_BIT,
-							&dd->dd_flag))) {
-			return -ENXIO;
-		}
-		if (unlikely(test_bit(MTIP_DDF_OVER_TEMP_BIT, &dd->dd_flag))) {
-			return -ENODATA;
-		}
-		if (unlikely(test_bit(MTIP_DDF_WRITE_PROTECT_BIT,
-							&dd->dd_flag) &&
-				rq_data_dir(rq))) {
-			return -ENODATA;
-		}
-		if (unlikely(test_bit(MTIP_DDF_SEC_LOCK_BIT, &dd->dd_flag) ||
-			test_bit(MTIP_DDF_REBUILD_FAILED_BIT, &dd->dd_flag)))
-			return -ENODATA;
-	}
-
-	if (req_op(rq) == REQ_OP_DISCARD) {
-		int err;
+	if (likely(!(dd->dd_flag & MTIP_DDF_STOP_IO)))
+		return false;
 
-		err = mtip_send_trim(dd, blk_rq_pos(rq), blk_rq_sectors(rq));
-		blk_mq_end_request(rq, err ? BLK_STS_IOERR : BLK_STS_OK);
-		return 0;
-	}
+	if (test_bit(MTIP_DDF_REMOVE_PENDING_BIT, &dd->dd_flag))
+		return true;
+	if (test_bit(MTIP_DDF_OVER_TEMP_BIT, &dd->dd_flag))
+		return true;
+	if (test_bit(MTIP_DDF_WRITE_PROTECT_BIT, &dd->dd_flag) &&
+	    rq_data_dir(rq))
+		return true;
+	if (test_bit(MTIP_DDF_SEC_LOCK_BIT, &dd->dd_flag))
+		return true;
+	if (test_bit(MTIP_DDF_REBUILD_FAILED_BIT, &dd->dd_flag))
+		return true;
 
-	/* Issue the read/write. */
-	mtip_hw_submit_io(dd, rq, cmd, hctx);
-	return 0;
+	return false;
 }
 
 static bool mtip_check_unal_depth(struct blk_mq_hw_ctx *hctx,
@@ -3647,8 +3617,9 @@ static blk_status_t mtip_issue_reserved_cmd(struct blk_mq_hw_ctx *hctx,
 static blk_status_t mtip_queue_rq(struct blk_mq_hw_ctx *hctx,
 			 const struct blk_mq_queue_data *bd)
 {
+	struct driver_data *dd = hctx->queue->queuedata;
 	struct request *rq = bd->rq;
-	int ret;
+	struct mtip_cmd *cmd = blk_mq_rq_to_pdu(rq);
 
 	mtip_init_cmd_header(rq);
 
@@ -3658,12 +3629,19 @@ static blk_status_t mtip_queue_rq(struct blk_mq_hw_ctx *hctx,
 	if (unlikely(mtip_check_unal_depth(hctx, rq)))
 		return BLK_STS_RESOURCE;
 
+	if (is_se_active(dd) || is_stopped(dd, rq))
+		return BLK_STS_IOERR;
+
 	blk_mq_start_request(rq);
 
-	ret = mtip_submit_request(hctx, rq);
-	if (likely(!ret))
-		return BLK_STS_OK;
-	return BLK_STS_IOERR;
+	if (req_op(rq) == REQ_OP_DISCARD) {
+		if (mtip_send_trim(dd, blk_rq_pos(rq), blk_rq_sectors(rq)) < 0)
+			return BLK_STS_IOERR;
+	} else {
+		mtip_hw_submit_io(dd, rq, cmd, hctx);
+	}
+
+	return BLK_STS_OK;
 }
 
 static void mtip_free_cmd(struct blk_mq_tag_set *set, struct request *rq,
-- 
2.19.1

[PATCH 3/9] mtip32xx: return a blk_status_t from mtip_send_trim

[Christoph Hellwig]

This allows for better error propagation and simpler code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 drivers/block/mtip32xx/mtip32xx.c | 30 +++++++++++-------------------
 1 file changed, 11 insertions(+), 19 deletions(-)

diff --git a/drivers/block/mtip32xx/mtip32xx.c b/drivers/block/mtip32xx/mtip32xx.c
index 75a4ca0210f2..d5277bba0c02 100644
--- a/drivers/block/mtip32xx/mtip32xx.c
+++ b/drivers/block/mtip32xx/mtip32xx.c
@@ -1423,23 +1423,19 @@ static int mtip_get_smart_attr(struct mtip_port *port, unsigned int id,
  * @dd		pointer to driver_data structure
  * @lba		starting lba
  * @len		# of 512b sectors to trim
- *
- * return value
- *      -ENOMEM		Out of dma memory
- *      -EINVAL		Invalid parameters passed in, trim not supported
- *      -EIO		Error submitting trim request to hw
  */
-static int mtip_send_trim(struct driver_data *dd, unsigned int lba,
-				unsigned int len)
+static blk_status_t mtip_send_trim(struct driver_data *dd, unsigned int lba,
+		unsigned int len)
 {
-	int i, rv = 0;
 	u64 tlba, tlen, sect_left;
 	struct mtip_trim_entry *buf;
 	dma_addr_t dma_addr;
 	struct host_to_dev_fis fis;
+	blk_status_t ret = BLK_STS_OK;
+	int i;
 
 	if (!len || dd->trim_supp == false)
-		return -EINVAL;
+		return BLK_STS_IOERR;
 
 	/* Trim request too big */
 	WARN_ON(len > (MTIP_MAX_TRIM_ENTRY_LEN * MTIP_MAX_TRIM_ENTRIES));
@@ -1454,7 +1450,7 @@ static int mtip_send_trim(struct driver_data *dd, unsigned int lba,
 	buf = dmam_alloc_coherent(&dd->pdev->dev, ATA_SECT_SIZE, &dma_addr,
 								GFP_KERNEL);
 	if (!buf)
-		return -ENOMEM;
+		return BLK_STS_RESOURCE;
 	memset(buf, 0, ATA_SECT_SIZE);
 
 	for (i = 0, sect_left = len, tlba = lba;
@@ -1486,10 +1482,10 @@ static int mtip_send_trim(struct driver_data *dd, unsigned int lba,
 					ATA_SECT_SIZE,
 					0,
 					MTIP_TRIM_TIMEOUT_MS) < 0)
-		rv = -EIO;
+		ret = BLK_STS_IOERR;
 
 	dmam_free_coherent(&dd->pdev->dev, ATA_SECT_SIZE, buf, dma_addr);
-	return rv;
+	return ret;
 }
 
 /*
@@ -3634,13 +3630,9 @@ static blk_status_t mtip_queue_rq(struct blk_mq_hw_ctx *hctx,
 
 	blk_mq_start_request(rq);
 
-	if (req_op(rq) == REQ_OP_DISCARD) {
-		if (mtip_send_trim(dd, blk_rq_pos(rq), blk_rq_sectors(rq)) < 0)
-			return BLK_STS_IOERR;
-	} else {
-		mtip_hw_submit_io(dd, rq, cmd, hctx);
-	}
-
+	if (req_op(rq) == REQ_OP_DISCARD)
+		return mtip_send_trim(dd, blk_rq_pos(rq), blk_rq_sectors(rq));
+	mtip_hw_submit_io(dd, rq, cmd, hctx);
 	return BLK_STS_OK;
 }
 
-- 
2.19.1

[PATCH 4/9] mtip32xx: remove __force_bit2int

[Christoph Hellwig]

There is no good excuse not to use proper __le16/32 types.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 drivers/block/mtip32xx/mtip32xx.c | 33 ++++++++++++-------------------
 drivers/block/mtip32xx/mtip32xx.h | 28 ++++++++++++--------------
 2 files changed, 26 insertions(+), 35 deletions(-)

diff --git a/drivers/block/mtip32xx/mtip32xx.c b/drivers/block/mtip32xx/mtip32xx.c
index d5277bba0c02..9245c325fe3c 100644
--- a/drivers/block/mtip32xx/mtip32xx.c
+++ b/drivers/block/mtip32xx/mtip32xx.c
@@ -181,9 +181,9 @@ static void mtip_init_cmd_header(struct request *rq)
 				(sizeof(struct mtip_cmd_hdr) * rq->tag);
 
 	if (test_bit(MTIP_PF_HOST_CAP_64, &dd->port->flags))
-		cmd->command_header->ctbau = __force_bit2int cpu_to_le32((cmd->command_dma >> 16) >> 16);
+		cmd->command_header->ctbau = cpu_to_le32((cmd->command_dma >> 16) >> 16);
 
-	cmd->command_header->ctba = __force_bit2int cpu_to_le32(cmd->command_dma & 0xFFFFFFFF);
+	cmd->command_header->ctba = cpu_to_le32(cmd->command_dma & 0xFFFFFFFF);
 }
 
 static struct mtip_cmd *mtip_get_int_command(struct driver_data *dd)
@@ -1459,8 +1459,8 @@ static blk_status_t mtip_send_trim(struct driver_data *dd, unsigned int lba,
 		tlen = (sect_left >= MTIP_MAX_TRIM_ENTRY_LEN ?
 					MTIP_MAX_TRIM_ENTRY_LEN :
 					sect_left);
-		buf[i].lba = __force_bit2int cpu_to_le32(tlba);
-		buf[i].range = __force_bit2int cpu_to_le16(tlen);
+		buf[i].lba = cpu_to_le32(tlba);
+		buf[i].range = cpu_to_le16(tlen);
 		tlba += tlen;
 		sect_left -= tlen;
 	}
@@ -1590,11 +1590,9 @@ static inline void fill_command_sg(struct driver_data *dd,
 		if (dma_len > 0x400000)
 			dev_err(&dd->pdev->dev,
 				"DMA segment length truncated\n");
-		command_sg->info = __force_bit2int
-			cpu_to_le32((dma_len-1) & 0x3FFFFF);
-		command_sg->dba	= __force_bit2int
-			cpu_to_le32(sg_dma_address(sg));
-		command_sg->dba_upper = __force_bit2int
+		command_sg->info = cpu_to_le32((dma_len-1) & 0x3FFFFF);
+		command_sg->dba	=  cpu_to_le32(sg_dma_address(sg));
+		command_sg->dba_upper =
 			cpu_to_le32((sg_dma_address(sg) >> 16) >> 16);
 		command_sg++;
 		sg++;
@@ -2231,8 +2229,7 @@ static void mtip_hw_submit_io(struct driver_data *dd, struct request *rq,
 
 	/* Populate the command header */
 	command->command_header->opts =
-			__force_bit2int cpu_to_le32(
-				(nents << 16) | 5 | AHCI_CMD_PREFETCH);
+			cpu_to_le32((nents << 16) | 5 | AHCI_CMD_PREFETCH);
 	command->command_header->byte_count = 0;
 
 	command->direction = dma_dir;
@@ -3586,20 +3583,16 @@ static blk_status_t mtip_issue_reserved_cmd(struct blk_mq_hw_ctx *hctx,
 		return BLK_STS_RESOURCE;
 
 	/* Populate the SG list */
-	cmd->command_header->opts =
-		 __force_bit2int cpu_to_le32(icmd->opts | icmd->fis_len);
+	cmd->command_header->opts = cpu_to_le32(icmd->opts | icmd->fis_len);
 	if (icmd->buf_len) {
 		command_sg = cmd->command + AHCI_CMD_TBL_HDR_SZ;
 
-		command_sg->info =
-			__force_bit2int cpu_to_le32((icmd->buf_len-1) & 0x3FFFFF);
-		command_sg->dba	=
-			__force_bit2int cpu_to_le32(icmd->buffer & 0xFFFFFFFF);
+		command_sg->info = cpu_to_le32((icmd->buf_len-1) & 0x3FFFFF);
+		command_sg->dba	= cpu_to_le32(icmd->buffer & 0xFFFFFFFF);
 		command_sg->dba_upper =
-			__force_bit2int cpu_to_le32((icmd->buffer >> 16) >> 16);
+			cpu_to_le32((icmd->buffer >> 16) >> 16);
 
-		cmd->command_header->opts |=
-			__force_bit2int cpu_to_le32((1 << 16));
+		cmd->command_header->opts |= cpu_to_le32((1 << 16));
 	}
 
 	/* Populate the command header */
diff --git a/drivers/block/mtip32xx/mtip32xx.h b/drivers/block/mtip32xx/mtip32xx.h
index e20e55dab443..0aa1ea210822 100644
--- a/drivers/block/mtip32xx/mtip32xx.h
+++ b/drivers/block/mtip32xx/mtip32xx.h
@@ -126,8 +126,6 @@
 
 #define MTIP_DFS_MAX_BUF_SIZE 1024
 
-#define __force_bit2int (unsigned int __force)
-
 enum {
 	/* below are bit numbers in 'flags' defined in mtip_port */
 	MTIP_PF_IC_ACTIVE_BIT       = 0, /* pio/ioctl */
@@ -200,9 +198,9 @@ struct mtip_work {
 #define MTIP_MAX_TRIM_ENTRY_LEN		0xfff8
 
 struct mtip_trim_entry {
-	u32 lba;   /* starting lba of region */
-	u16 rsvd;  /* unused */
-	u16 range; /* # of 512b blocks to trim */
+	__le32 lba;   /* starting lba of region */
+	__le16 rsvd;  /* unused */
+	__le16 range; /* # of 512b blocks to trim */
 } __packed;
 
 struct mtip_trim {
@@ -278,24 +276,24 @@ struct mtip_cmd_hdr {
 	 * - Bit 5 Unused in this implementation.
 	 * - Bits 4:0 Length of the command FIS in DWords (DWord = 4 bytes).
 	 */
-	unsigned int opts;
+	__le32 opts;
 	/* This field is unsed when using NCQ. */
 	union {
-		unsigned int byte_count;
-		unsigned int status;
+		__le32 byte_count;
+		__le32 status;
 	};
 	/*
 	 * Lower 32 bits of the command table address associated with this
 	 * header. The command table addresses must be 128 byte aligned.
 	 */
-	unsigned int ctba;
+	__le32 ctba;
 	/*
 	 * If 64 bit addressing is used this field is the upper 32 bits
 	 * of the command table address associated with this command.
 	 */
-	unsigned int ctbau;
+	__le32 ctbau;
 	/* Reserved and unused. */
-	unsigned int res[4];
+	u32 res[4];
 };
 
 /* Command scatter gather structure (PRD). */
@@ -305,21 +303,21 @@ struct mtip_cmd_sg {
 	 * address must be 8 byte aligned signified by bits 2:0 being
 	 * set to 0.
 	 */
-	unsigned int dba;
+	__le32 dba;
 	/*
 	 * When 64 bit addressing is used this field is the upper
 	 * 32 bits of the data buffer address.
 	 */
-	unsigned int dba_upper;
+	__le32 dba_upper;
 	/* Unused. */
-	unsigned int reserved;
+	__le32 reserved;
 	/*
 	 * Bit 31: interrupt when this data block has been transferred.
 	 * Bits 30..22: reserved
 	 * Bits 21..0: byte count (minus 1).  For P320 the byte count must be
 	 * 8 byte aligned signified by bits 2:0 being set to 1.
 	 */
-	unsigned int info;
+	__le32 info;
 };
 struct mtip_port;
 
-- 
2.19.1

[PATCH 5/9] mtip32xx: add missing endianess annotations on struct smart_attr

[Christoph Hellwig]

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 drivers/block/mtip32xx/mtip32xx.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/block/mtip32xx/mtip32xx.h b/drivers/block/mtip32xx/mtip32xx.h
index 0aa1ea210822..e8b4b3d5365a 100644
--- a/drivers/block/mtip32xx/mtip32xx.h
+++ b/drivers/block/mtip32xx/mtip32xx.h
@@ -172,10 +172,10 @@ enum {
 
 struct smart_attr {
 	u8 attr_id;
-	u16 flags;
+	__le16 flags;
 	u8 cur;
 	u8 worst;
-	u32 data;
+	__le32 data;
 	u8 res[3];
 } __packed;
 
-- 
2.19.1

[PATCH 6/9] mtip32xx: remove mtip_init_cmd_header

[Christoph Hellwig]

There isn't much need for this helper - we can just calculate the offset
for the command header once late in the submission path and fill out
the ctba and ctbau fields there.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 drivers/block/mtip32xx/mtip32xx.c | 44 +++++++++++--------------------
 drivers/block/mtip32xx/mtip32xx.h |  5 ----
 2 files changed, 15 insertions(+), 34 deletions(-)

diff --git a/drivers/block/mtip32xx/mtip32xx.c b/drivers/block/mtip32xx/mtip32xx.c
index 9245c325fe3c..6006f7baa1eb 100644
--- a/drivers/block/mtip32xx/mtip32xx.c
+++ b/drivers/block/mtip32xx/mtip32xx.c
@@ -168,24 +168,6 @@ static bool mtip_check_surprise_removal(struct pci_dev *pdev)
 	return false; /* device present */
 }
 
-/* we have to use runtime tag to setup command header */
-static void mtip_init_cmd_header(struct request *rq)
-{
-	struct driver_data *dd = rq->q->queuedata;
-	struct mtip_cmd *cmd = blk_mq_rq_to_pdu(rq);
-
-	/* Point the command headers at the command tables. */
-	cmd->command_header = dd->port->command_list +
-				(sizeof(struct mtip_cmd_hdr) * rq->tag);
-	cmd->command_header_dma = dd->port->command_list_dma +
-				(sizeof(struct mtip_cmd_hdr) * rq->tag);
-
-	if (test_bit(MTIP_PF_HOST_CAP_64, &dd->port->flags))
-		cmd->command_header->ctbau = cpu_to_le32((cmd->command_dma >> 16) >> 16);
-
-	cmd->command_header->ctba = cpu_to_le32(cmd->command_dma & 0xFFFFFFFF);
-}
-
 static struct mtip_cmd *mtip_get_int_command(struct driver_data *dd)
 {
 	struct request *rq;
@@ -197,9 +179,6 @@ static struct mtip_cmd *mtip_get_int_command(struct driver_data *dd)
 	if (IS_ERR(rq))
 		return NULL;
 
-	/* Internal cmd isn't submitted via .queue_rq */
-	mtip_init_cmd_header(rq);
-
 	return blk_mq_rq_to_pdu(rq);
 }
 
@@ -2179,6 +2158,8 @@ static void mtip_hw_submit_io(struct driver_data *dd, struct request *rq,
 			      struct mtip_cmd *command,
 			      struct blk_mq_hw_ctx *hctx)
 {
+	struct mtip_cmd_hdr *hdr =
+		dd->port->command_list + sizeof(struct mtip_cmd_hdr) * rq->tag;
 	struct host_to_dev_fis	*fis;
 	struct mtip_port *port = dd->port;
 	int dma_dir = rq_data_dir(rq) == READ ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
@@ -2228,9 +2209,11 @@ static void mtip_hw_submit_io(struct driver_data *dd, struct request *rq,
 		fis->device |= 1 << 7;
 
 	/* Populate the command header */
-	command->command_header->opts =
-			cpu_to_le32((nents << 16) | 5 | AHCI_CMD_PREFETCH);
-	command->command_header->byte_count = 0;
+	hdr->ctba = cpu_to_le32(command->command_dma & 0xFFFFFFFF);
+	if (test_bit(MTIP_PF_HOST_CAP_64, &dd->port->flags))
+		hdr->ctbau = cpu_to_le32((command->command_dma >> 16) >> 16);
+	hdr->opts = cpu_to_le32((nents << 16) | 5 | AHCI_CMD_PREFETCH);
+	hdr->byte_count = 0;
 
 	command->direction = dma_dir;
 
@@ -3577,13 +3560,18 @@ static blk_status_t mtip_issue_reserved_cmd(struct blk_mq_hw_ctx *hctx,
 	struct driver_data *dd = hctx->queue->queuedata;
 	struct mtip_int_cmd *icmd = rq->special;
 	struct mtip_cmd *cmd = blk_mq_rq_to_pdu(rq);
+	struct mtip_cmd_hdr *hdr =
+		dd->port->command_list + sizeof(struct mtip_cmd_hdr) * rq->tag;
 	struct mtip_cmd_sg *command_sg;
 
 	if (mtip_commands_active(dd->port))
 		return BLK_STS_RESOURCE;
 
+	hdr->ctba = cpu_to_le32(cmd->command_dma & 0xFFFFFFFF);
+	if (test_bit(MTIP_PF_HOST_CAP_64, &dd->port->flags))
+		hdr->ctbau = cpu_to_le32((cmd->command_dma >> 16) >> 16);
 	/* Populate the SG list */
-	cmd->command_header->opts = cpu_to_le32(icmd->opts | icmd->fis_len);
+	hdr->opts = cpu_to_le32(icmd->opts | icmd->fis_len);
 	if (icmd->buf_len) {
 		command_sg = cmd->command + AHCI_CMD_TBL_HDR_SZ;
 
@@ -3592,11 +3580,11 @@ static blk_status_t mtip_issue_reserved_cmd(struct blk_mq_hw_ctx *hctx,
 		command_sg->dba_upper =
 			cpu_to_le32((icmd->buffer >> 16) >> 16);
 
-		cmd->command_header->opts |= cpu_to_le32((1 << 16));
+		hdr->opts |= cpu_to_le32((1 << 16));
 	}
 
 	/* Populate the command header */
-	cmd->command_header->byte_count = 0;
+	hdr->byte_count = 0;
 
 	blk_mq_start_request(rq);
 	mtip_issue_non_ncq_command(dd->port, rq->tag);
@@ -3610,8 +3598,6 @@ static blk_status_t mtip_queue_rq(struct blk_mq_hw_ctx *hctx,
 	struct request *rq = bd->rq;
 	struct mtip_cmd *cmd = blk_mq_rq_to_pdu(rq);
 
-	mtip_init_cmd_header(rq);
-
 	if (blk_rq_is_passthrough(rq))
 		return mtip_issue_reserved_cmd(hctx, rq);
 
diff --git a/drivers/block/mtip32xx/mtip32xx.h b/drivers/block/mtip32xx/mtip32xx.h
index e8b4b3d5365a..63414928f07c 100644
--- a/drivers/block/mtip32xx/mtip32xx.h
+++ b/drivers/block/mtip32xx/mtip32xx.h
@@ -323,11 +323,6 @@ struct mtip_port;
 
 /* Structure used to describe a command. */
 struct mtip_cmd {
-
-	struct mtip_cmd_hdr *command_header; /* ptr to command header entry */
-
-	dma_addr_t command_header_dma; /* corresponding physical address */
-
 	void *command; /* ptr to command table entry */
 
 	dma_addr_t command_dma; /* corresponding physical address */
-- 
2.19.1

[PATCH 7/9] mtip32xx: remove mtip_get_int_command

[Christoph Hellwig]

Merging this function into the only callers makes the code flow easier.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 drivers/block/mtip32xx/mtip32xx.c | 24 +++++++-----------------
 1 file changed, 7 insertions(+), 17 deletions(-)

diff --git a/drivers/block/mtip32xx/mtip32xx.c b/drivers/block/mtip32xx/mtip32xx.c
index 6006f7baa1eb..5ae86224b2f5 100644
--- a/drivers/block/mtip32xx/mtip32xx.c
+++ b/drivers/block/mtip32xx/mtip32xx.c
@@ -168,20 +168,6 @@ static bool mtip_check_surprise_removal(struct pci_dev *pdev)
 	return false; /* device present */
 }
 
-static struct mtip_cmd *mtip_get_int_command(struct driver_data *dd)
-{
-	struct request *rq;
-
-	if (mtip_check_surprise_removal(dd->pdev))
-		return NULL;
-
-	rq = blk_mq_alloc_request(dd->queue, REQ_OP_DRV_IN, BLK_MQ_REQ_RESERVED);
-	if (IS_ERR(rq))
-		return NULL;
-
-	return blk_mq_rq_to_pdu(rq);
-}
-
 static struct mtip_cmd *mtip_cmd_from_tag(struct driver_data *dd,
 					  unsigned int tag)
 {
@@ -1002,12 +988,15 @@ static int mtip_exec_internal_command(struct mtip_port *port,
 		return -EFAULT;
 	}
 
-	int_cmd = mtip_get_int_command(dd);
-	if (!int_cmd) {
+	if (mtip_check_surprise_removal(dd->pdev))
+		return -EFAULT;
+
+	rq = blk_mq_alloc_request(dd->queue, REQ_OP_DRV_IN, BLK_MQ_REQ_RESERVED);
+	if (IS_ERR(rq)) {
 		dbg_printk(MTIP_DRV_NAME "Unable to allocate tag for PIO cmd\n");
 		return -EFAULT;
 	}
-	rq = blk_mq_rq_from_pdu(int_cmd);
+
 	rq->special = &icmd;
 
 	set_bit(MTIP_PF_IC_ACTIVE_BIT, &port->flags);
@@ -1029,6 +1018,7 @@ static int mtip_exec_internal_command(struct mtip_port *port,
 	}
 
 	/* Copy the command to the command table */
+	int_cmd = blk_mq_rq_to_pdu(rq);
 	memcpy(int_cmd->command, fis, fis_len*4);
 
 	rq->timeout = timeout;
-- 
2.19.1

[PATCH 8/9] mtip32xx: don't use req->special

[Christoph Hellwig]

Instead create add to the icmd into struct mtip_cmd which can be unioned
with the scatterlist used for the normal I/O path.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 drivers/block/mtip32xx/mtip32xx.c | 5 ++---
 drivers/block/mtip32xx/mtip32xx.h | 7 ++++++-
 2 files changed, 8 insertions(+), 4 deletions(-)

diff --git a/drivers/block/mtip32xx/mtip32xx.c b/drivers/block/mtip32xx/mtip32xx.c
index 5ae86224b2f5..e99db2c9118f 100644
--- a/drivers/block/mtip32xx/mtip32xx.c
+++ b/drivers/block/mtip32xx/mtip32xx.c
@@ -997,8 +997,6 @@ static int mtip_exec_internal_command(struct mtip_port *port,
 		return -EFAULT;
 	}
 
-	rq->special = &icmd;
-
 	set_bit(MTIP_PF_IC_ACTIVE_BIT, &port->flags);
 
 	if (fis->command == ATA_CMD_SEC_ERASE_PREP)
@@ -1019,6 +1017,7 @@ static int mtip_exec_internal_command(struct mtip_port *port,
 
 	/* Copy the command to the command table */
 	int_cmd = blk_mq_rq_to_pdu(rq);
+	int_cmd->icmd = &icmd;
 	memcpy(int_cmd->command, fis, fis_len*4);
 
 	rq->timeout = timeout;
@@ -3548,8 +3547,8 @@ static blk_status_t mtip_issue_reserved_cmd(struct blk_mq_hw_ctx *hctx,
 		struct request *rq)
 {
 	struct driver_data *dd = hctx->queue->queuedata;
-	struct mtip_int_cmd *icmd = rq->special;
 	struct mtip_cmd *cmd = blk_mq_rq_to_pdu(rq);
+	struct mtip_int_cmd *icmd = cmd->icmd;
 	struct mtip_cmd_hdr *hdr =
 		dd->port->command_list + sizeof(struct mtip_cmd_hdr) * rq->tag;
 	struct mtip_cmd_sg *command_sg;
diff --git a/drivers/block/mtip32xx/mtip32xx.h b/drivers/block/mtip32xx/mtip32xx.h
index 63414928f07c..c33f8c3d9fb4 100644
--- a/drivers/block/mtip32xx/mtip32xx.h
+++ b/drivers/block/mtip32xx/mtip32xx.h
@@ -321,6 +321,8 @@ struct mtip_cmd_sg {
 };
 struct mtip_port;
 
+struct mtip_int_cmd;
+
 /* Structure used to describe a command. */
 struct mtip_cmd {
 	void *command; /* ptr to command table entry */
@@ -331,7 +333,10 @@ struct mtip_cmd {
 
 	int unaligned; /* command is unaligned on 4k boundary */
 
-	struct scatterlist sg[MTIP_MAX_SG]; /* Scatter list entries */
+	union {
+		struct scatterlist sg[MTIP_MAX_SG]; /* Scatter list entries */
+		struct mtip_int_cmd *icmd;
+	};
 
 	int retries; /* The number of retries left for this command. */
 
-- 
2.19.1

[PATCH 9/9] mtip32xxx: use for_each_sg

[Christoph Hellwig]

Use the proper helper instead of manually iterating the scatterlist,
which is broken in the presence of chained S/G lists.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 drivers/block/mtip32xx/mtip32xx.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/drivers/block/mtip32xx/mtip32xx.c b/drivers/block/mtip32xx/mtip32xx.c
index e99db2c9118f..a4c44db097e0 100644
--- a/drivers/block/mtip32xx/mtip32xx.c
+++ b/drivers/block/mtip32xx/mtip32xx.c
@@ -1549,11 +1549,11 @@ static inline void fill_command_sg(struct driver_data *dd,
 	int n;
 	unsigned int dma_len;
 	struct mtip_cmd_sg *command_sg;
-	struct scatterlist *sg = command->sg;
+	struct scatterlist *sg;
 
 	command_sg = command->command + AHCI_CMD_TBL_HDR_SZ;
 
-	for (n = 0; n < nents; n++) {
+	for_each_sg(command->sg, sg, nents, n) {
 		dma_len = sg_dma_len(sg);
 		if (dma_len > 0x400000)
 			dev_err(&dd->pdev->dev,
@@ -1563,7 +1563,6 @@ static inline void fill_command_sg(struct driver_data *dd,
 		command_sg->dba_upper =
 			cpu_to_le32((sg_dma_address(sg) >> 16) >> 16);
 		command_sg++;
-		sg++;
 	}
 }
 
-- 
2.19.1

Re: mtip32xx: fixes and cleanups

[Jens Axboe]

On 11/9/18 6:48 AM, Christoph Hellwig wrote:
> Various low hanging fruit, kicked of by seeing one of the few remaining
> req->special users.
> 
> Compile tested only.

Looks good to me - as it so happens, I do have a few of these cards.
Tested working fine after the patches.

-- 
Jens Axboe