diff mbox

[12/20] scsi_dh_alua: allocate RTPG buffer separately

Message ID 1436346378-96518-13-git-send-email-hare@suse.de (mailing list archive)
State New, archived
Headers show

Commit Message

Hannes Reinecke July 8, 2015, 9:06 a.m. UTC 
The RTPG buffer will only evaluated within alua_rtpg(),
so we can allocate it locally there and avoid having to
put it into the global structure.

Signed-off-by: Hannes Reinecke <hare@suse.de>
---
 drivers/scsi/device_handler/scsi_dh_alua.c | 55 ++++++++++++------------------
 1 file changed, 21 insertions(+), 34 deletions(-)

Comments

Christoph Hellwig July 24, 2015, 2:59 p.m. UTC | #1 
Looks good,

Reviewed-by: Christoph Hellwig <hch@lst.de>
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diff mbox

Patch

diff --git a/drivers/scsi/device_handler/scsi_dh_alua.c b/drivers/scsi/device_handler/scsi_dh_alua.c
index 3f18f6b..e8bfbce 100644
--- a/drivers/scsi/device_handler/scsi_dh_alua.c
+++ b/drivers/scsi/device_handler/scsi_dh_alua.c
@@ -56,7 +56,7 @@ 
 #define TPGS_MODE_IMPLICIT		0x1
 #define TPGS_MODE_EXPLICIT		0x2
 
-#define ALUA_INQUIRY_SIZE		36
+#define ALUA_RTPG_SIZE			128
 #define ALUA_FAILOVER_TIMEOUT		60
 #define ALUA_FAILOVER_RETRIES		5
 
@@ -75,9 +75,6 @@  struct alua_port_group {
 	int			state;
 	int			pref;
 	unsigned		flags; /* used for optimizing STPG */
-	unsigned char		inq[ALUA_INQUIRY_SIZE];
-	unsigned char		*buff;
-	int			bufflen;
 	unsigned char		transition_tmo;
 };
 
@@ -96,21 +93,6 @@  struct alua_dh_data {
 static char print_alua_state(int);
 static int alua_check_sense(struct scsi_device *, struct scsi_sense_hdr *);
 
-static int realloc_buffer(struct alua_port_group *pg, unsigned len)
-{
-	if (pg->buff && pg->buff != pg->inq)
-		kfree(pg->buff);
-
-	pg->buff = kmalloc(len, GFP_NOIO);
-	if (!pg->buff) {
-		pg->buff = pg->inq;
-		pg->bufflen = ALUA_INQUIRY_SIZE;
-		return 1;
-	}
-	pg->bufflen = len;
-	return 0;
-}
-
 static void release_port_group(struct kref *kref)
 {
 	struct alua_port_group *pg;
@@ -120,8 +102,6 @@  static void release_port_group(struct kref *kref)
 	spin_lock(&port_group_lock);
 	list_del(&pg->node);
 	spin_unlock(&port_group_lock);
-	if (pg->buff && pg->inq != pg->buff)
-		kfree(pg->buff);
 	kfree(pg);
 }
 
@@ -298,8 +278,6 @@  static int alua_check_vpd(struct scsi_device *sdev, struct alua_dh_data *h)
 		return SCSI_DH_DEV_TEMP_BUSY;
 	}
 	pg->group_id = group_id;
-	pg->buff = pg->inq;
-	pg->bufflen = ALUA_INQUIRY_SIZE;
 	pg->tpgs = h->tpgs;
 	pg->state = TPGS_STATE_OPTIMIZED;
 	kref_init(&pg->kref);
@@ -423,8 +401,8 @@  static int alua_rtpg(struct scsi_device *sdev, struct alua_port_group *pg, int w
 {
 	unsigned char sense[SCSI_SENSE_BUFFERSIZE];
 	struct scsi_sense_hdr sense_hdr;
-	int len, k, off, valid_states = 0;
-	unsigned char *ucp;
+	int len, k, off, valid_states = 0, bufflen = ALUA_RTPG_SIZE;
+	unsigned char *ucp, *buff;
 	unsigned err, retval;
 	unsigned long expiry, interval = 0;
 	unsigned int tpg_desc_tbl_off;
@@ -435,8 +413,12 @@  static int alua_rtpg(struct scsi_device *sdev, struct alua_port_group *pg, int w
 	else
 		expiry = round_jiffies_up(jiffies + pg->transition_tmo * HZ);
 
+	buff = kzalloc(bufflen, GFP_KERNEL);
+	if (!buff)
+		return SCSI_DH_DEV_TEMP_BUSY;
+
  retry:
-	retval = submit_rtpg(sdev, pg->buff, pg->bufflen, sense, pg->flags);
+	retval = submit_rtpg(sdev, buff, bufflen, sense, pg->flags);
 
 	if (retval) {
 		if (!(driver_byte(retval) & DRIVER_SENSE) ||
@@ -449,6 +431,7 @@  static int alua_rtpg(struct scsi_device *sdev, struct alua_port_group *pg, int w
 				err = SCSI_DH_DEV_TEMP_BUSY;
 			else
 				err = SCSI_DH_IO;
+			kfree(buff);
 			return err;
 		}
 
@@ -477,14 +460,18 @@  static int alua_rtpg(struct scsi_device *sdev, struct alua_port_group *pg, int w
 		sdev_printk(KERN_ERR, sdev, "%s: rtpg failed\n",
 			    ALUA_DH_NAME);
 		scsi_print_sense_hdr(sdev, ALUA_DH_NAME, &sense_hdr);
+		kfree(buff);
 		return SCSI_DH_IO;
 	}
 
-	len = get_unaligned_be32(&pg->buff[0]) + 4;
+	len = get_unaligned_be32(&buff[0]) + 4;
 
-	if (len > pg->bufflen) {
+	if (len > bufflen) {
 		/* Resubmit with the correct length */
-		if (realloc_buffer(pg, len)) {
+		kfree(buff);
+		bufflen = len;
+		buff = kmalloc(bufflen, GFP_KERNEL);
+		if (!buff) {
 			sdev_printk(KERN_WARNING, sdev,
 				    "%s: kmalloc buffer failed\n",__func__);
 			/* Temporary failure, bypass */
@@ -494,9 +481,8 @@  static int alua_rtpg(struct scsi_device *sdev, struct alua_port_group *pg, int w
 	}
 
 	orig_transition_tmo = pg->transition_tmo;
-	if ((pg->buff[4] & RTPG_FMT_MASK) == RTPG_FMT_EXT_HDR &&
-	    pg->buff[5] != 0)
-		pg->transition_tmo = pg->buff[5];
+	if ((buff[4] & RTPG_FMT_MASK) == RTPG_FMT_EXT_HDR && buff[5] != 0)
+		pg->transition_tmo = buff[5];
 	else
 		pg->transition_tmo = ALUA_FAILOVER_TIMEOUT;
 
@@ -507,12 +493,12 @@  static int alua_rtpg(struct scsi_device *sdev, struct alua_port_group *pg, int w
 		expiry = jiffies + pg->transition_tmo * HZ;
 	}
 
-	if ((pg->buff[4] & RTPG_FMT_MASK) == RTPG_FMT_EXT_HDR)
+	if ((buff[4] & RTPG_FMT_MASK) == RTPG_FMT_EXT_HDR)
 		tpg_desc_tbl_off = 8;
 	else
 		tpg_desc_tbl_off = 4;
 
-	for (k = tpg_desc_tbl_off, ucp = pg->buff + tpg_desc_tbl_off;
+	for (k = tpg_desc_tbl_off, ucp = buff + tpg_desc_tbl_off;
 	     k < len;
 	     k += off, ucp += off) {
 
@@ -562,6 +548,7 @@  static int alua_rtpg(struct scsi_device *sdev, struct alua_port_group *pg, int w
 		err = SCSI_DH_OK;
 		break;
 	}
+	kfree(buff);
 	return err;
 }