diff mbox

[6/6] libata: switch to dynamic allocation insted of ata_scsi_rbuf

Message ID 1484037708-654-7-git-send-email-hch@lst.de
State Not Applicable
Delegated to: David Miller
Headers show

Commit Message

Christoph Hellwig Jan. 10, 2017, 8:41 a.m. UTC 
Note of the emulated commands in the pageout/pagein path, so just do
a GFP_NOIO dynamic allocation.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 drivers/ata/libata-scsi.c | 122 ++++++++++++++--------------------------------
 1 file changed, 36 insertions(+), 86 deletions(-)

Comments

Christoph Hellwig Jan. 10, 2017, 2:40 p.m. UTC | #1 
>  	struct scsi_cmnd *scmd = qc->scsicmd;
>  	struct scsi_device *sdp = scmd->device;
> -	size_t len = sdp->sector_size;
> +	ssize_t len = sdp->sector_size;

Julia Lawall's magic checker tool pointed out that len doesn't have
to change to ssize_t here, but the size variable should instead so that
we can properly handle the ENOMEM case below.

I'll wait for some more feedback on the patches and will eventually
resend with that fix.
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diff mbox

Patch

diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c
index 395c859..785eb382 100644
--- a/drivers/ata/libata-scsi.c
+++ b/drivers/ata/libata-scsi.c
@@ -57,9 +57,6 @@ 
 
 #define ATA_SCSI_RBUF_SIZE	4096
 
-static DEFINE_SPINLOCK(ata_scsi_rbuf_lock);
-static u8 ata_scsi_rbuf[ATA_SCSI_RBUF_SIZE];
-
 typedef unsigned int (*ata_xlat_func_t)(struct ata_queued_cmd *qc);
 
 static struct ata_device *__ata_scsi_find_dev(struct ata_port *ap,
@@ -2057,53 +2054,6 @@  struct ata_scsi_args {
 };
 
 /**
- *	ata_scsi_rbuf_get - Map response buffer.
- *	@cmd: SCSI command containing buffer to be mapped.
- *	@flags: unsigned long variable to store irq enable status
- *	@copy_in: copy in from user buffer
- *
- *	Prepare buffer for simulated SCSI commands.
- *
- *	LOCKING:
- *	spin_lock_irqsave(ata_scsi_rbuf_lock) on success
- *
- *	RETURNS:
- *	Pointer to response buffer.
- */
-static void *ata_scsi_rbuf_get(struct scsi_cmnd *cmd, bool copy_in,
-			       unsigned long *flags)
-{
-	spin_lock_irqsave(&ata_scsi_rbuf_lock, *flags);
-
-	memset(ata_scsi_rbuf, 0, ATA_SCSI_RBUF_SIZE);
-	if (copy_in)
-		sg_copy_to_buffer(scsi_sglist(cmd), scsi_sg_count(cmd),
-				  ata_scsi_rbuf, ATA_SCSI_RBUF_SIZE);
-	return ata_scsi_rbuf;
-}
-
-/**
- *	ata_scsi_rbuf_put - Unmap response buffer.
- *	@cmd: SCSI command containing buffer to be unmapped.
- *	@copy_out: copy out result
- *	@flags: @flags passed to ata_scsi_rbuf_get()
- *
- *	Returns rbuf buffer.  The result is copied to @cmd's buffer if
- *	@copy_back is true.
- *
- *	LOCKING:
- *	Unlocks ata_scsi_rbuf_lock.
- */
-static inline void ata_scsi_rbuf_put(struct scsi_cmnd *cmd, bool copy_out,
-				     unsigned long *flags)
-{
-	if (copy_out)
-		sg_copy_from_buffer(scsi_sglist(cmd), scsi_sg_count(cmd),
-				    ata_scsi_rbuf, ATA_SCSI_RBUF_SIZE);
-	spin_unlock_irqrestore(&ata_scsi_rbuf_lock, *flags);
-}
-
-/**
  *	ata_scsi_rbuf_fill - wrapper for SCSI command simulators
  *	@args: device IDENTIFY data / SCSI command of interest.
  *	@actor: Callback hook for desired SCSI command simulator
@@ -2121,17 +2071,22 @@  static inline void ata_scsi_rbuf_put(struct scsi_cmnd *cmd, bool copy_out,
 static void ata_scsi_rbuf_fill(struct ata_scsi_args *args,
 		unsigned int (*actor)(struct ata_scsi_args *args, u8 *rbuf))
 {
-	u8 *rbuf;
-	unsigned int rc;
 	struct scsi_cmnd *cmd = args->cmd;
-	unsigned long flags;
+	u8 *buf;
 
-	rbuf = ata_scsi_rbuf_get(cmd, false, &flags);
-	rc = actor(args, rbuf);
-	ata_scsi_rbuf_put(cmd, rc == 0, &flags);
+	buf = kzalloc(ATA_SCSI_RBUF_SIZE, GFP_NOIO);
+	if (!buf) {
+		ata_scsi_set_sense(args->dev, cmd, NOT_READY, 0x08, 0);
+		return;
+	}
 
-	if (rc == 0)
+	if (actor(args, buf) == 0) {
+		sg_copy_from_buffer(scsi_sglist(cmd), scsi_sg_count(cmd),
+				    buf, ATA_SCSI_RBUF_SIZE);
 		cmd->result = SAM_STAT_GOOD;
+	}
+
+	kfree(buf);
 }
 
 /**
@@ -3363,24 +3318,17 @@  static unsigned int ata_scsi_pass_thru(struct ata_queued_cmd *qc)
  *
  * Return: Number of bytes copied into sglist.
  */
-static size_t ata_format_dsm_trim_descr(struct scsi_cmnd *cmd, u32 trmax,
+static ssize_t ata_format_dsm_trim_descr(struct scsi_cmnd *cmd, u32 trmax,
 					u64 sector, u32 count)
 {
-	struct scsi_device *sdp = cmd->device;
-	size_t len = sdp->sector_size;
 	size_t r;
 	__le64 *buf;
 	u32 i = 0;
-	unsigned long flags;
 
-	WARN_ON(len > ATA_SCSI_RBUF_SIZE);
-
-	if (len > ATA_SCSI_RBUF_SIZE)
-		len = ATA_SCSI_RBUF_SIZE;
+	buf = kzalloc(cmd->device->sector_size, GFP_NOFS);
+	if (!buf)
+		return -ENOMEM;
 
-	spin_lock_irqsave(&ata_scsi_rbuf_lock, flags);
-	buf = ((void *)ata_scsi_rbuf);
-	memset(buf, 0, len);
 	while (i < trmax) {
 		u64 entry = sector |
 			((u64)(count > 0xffff ? 0xffff : count) << 48);
@@ -3390,9 +3338,9 @@  static size_t ata_format_dsm_trim_descr(struct scsi_cmnd *cmd, u32 trmax,
 		count -= 0xffff;
 		sector += 0xffff;
 	}
-	r = sg_copy_from_buffer(scsi_sglist(cmd), scsi_sg_count(cmd), buf, len);
-	spin_unlock_irqrestore(&ata_scsi_rbuf_lock, flags);
-
+	r = sg_copy_from_buffer(scsi_sglist(cmd), scsi_sg_count(cmd), buf,
+			cmd->device->sector_size);
+	kfree(buf);
 	return r;
 }
 
@@ -3408,16 +3356,15 @@  static size_t ata_format_dsm_trim_descr(struct scsi_cmnd *cmd, u32 trmax,
  *
  * Return: Number of bytes copied into sglist.
  */
-static size_t ata_format_sct_write_same(struct scsi_cmnd *cmd, u64 lba, u64 num)
+static ssize_t ata_format_sct_write_same(struct scsi_cmnd *cmd, u64 lba,
+		u64 num)
 {
-	struct scsi_device *sdp = cmd->device;
-	size_t len = sdp->sector_size;
 	size_t r;
 	u16 *buf;
-	unsigned long flags;
 
-	spin_lock_irqsave(&ata_scsi_rbuf_lock, flags);
-	buf = ((void *)ata_scsi_rbuf);
+	buf = kzalloc(cmd->device->sector_size, GFP_NOIO);
+	if (!buf)
+		return -ENOMEM;
 
 	put_unaligned_le16(0x0002,  &buf[0]); /* SCT_ACT_WRITE_SAME */
 	put_unaligned_le16(0x0101,  &buf[1]); /* WRITE PTRN FG */
@@ -3425,14 +3372,9 @@  static size_t ata_format_sct_write_same(struct scsi_cmnd *cmd, u64 lba, u64 num)
 	put_unaligned_le64(num,     &buf[6]);
 	put_unaligned_le32(0u,      &buf[10]); /* pattern */
 
-	WARN_ON(len > ATA_SCSI_RBUF_SIZE);
-
-	if (len > ATA_SCSI_RBUF_SIZE)
-		len = ATA_SCSI_RBUF_SIZE;
-
-	r = sg_copy_from_buffer(scsi_sglist(cmd), scsi_sg_count(cmd), buf, len);
-	spin_unlock_irqrestore(&ata_scsi_rbuf_lock, flags);
-
+	r = sg_copy_from_buffer(scsi_sglist(cmd), scsi_sg_count(cmd), buf,
+			cmd->device->sector_size);
+	kfree(buf);
 	return r;
 }
 
@@ -3451,7 +3393,7 @@  static unsigned int ata_scsi_write_same_xlat(struct ata_queued_cmd *qc)
 	struct ata_taskfile *tf = &qc->tf;
 	struct scsi_cmnd *scmd = qc->scsicmd;
 	struct scsi_device *sdp = scmd->device;
-	size_t len = sdp->sector_size;
+	ssize_t len = sdp->sector_size;
 	struct ata_device *dev = qc->dev;
 	const u8 *cdb = scmd->cmnd;
 	u64 block;
@@ -3508,6 +3450,8 @@  static unsigned int ata_scsi_write_same_xlat(struct ata_queued_cmd *qc)
 	 */
 	if (unmap) {
 		size = ata_format_dsm_trim_descr(scmd, trmax, block, n_block);
+		if (size < 0)
+			goto comm_fail;
 		if (size != len)
 			goto invalid_param_len;
 
@@ -3531,6 +3475,8 @@  static unsigned int ata_scsi_write_same_xlat(struct ata_queued_cmd *qc)
 		}
 	} else {
 		size = ata_format_sct_write_same(scmd, block, n_block);
+		if (size < 0)
+			goto comm_fail;
 		if (size != len)
 			goto invalid_param_len;
 
@@ -3569,6 +3515,10 @@  static unsigned int ata_scsi_write_same_xlat(struct ata_queued_cmd *qc)
 	/* "Invalid command operation code" */
 	ata_scsi_set_sense(dev, scmd, ILLEGAL_REQUEST, 0x20, 0x0);
 	return 1;
+comm_fail:
+	/* "Logical unit communication failure" */
+	ata_scsi_set_sense(dev, scmd, NOT_READY, 0x08, 0);
+	return 1;
 }
 
 /**