From c49c83458f73d9fff7f441fb73268af3d15cfe52 Mon Sep 17 00:00:00 2001 From: Hannes Reinecke Date: Fri, 19 Feb 2016 09:17:03 +0100 Subject: [PATCH] scsi_dh_alua: allocate RTPG buffer separately 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. Reviewed-by: Ewan Milne Reviewed-by: Christoph Hellwig Signed-off-by: Hannes Reinecke Signed-off-by: Martin K. Petersen --- drivers/scsi/device_handler/scsi_dh_alua.c | 57 ++++++++++++------------------ 1 file changed, 23 insertions(+), 34 deletions(-) diff --git a/drivers/scsi/device_handler/scsi_dh_alua.c b/drivers/scsi/device_handler/scsi_dh_alua.c index 73df60e..af5acc1 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 @@ -71,9 +71,6 @@ struct alua_dh_data { 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; struct scsi_device *sdev; activate_complete callback_fn; @@ -85,21 +82,6 @@ struct alua_dh_data { static char print_alua_state(int); -static int realloc_buffer(struct alua_dh_data *h, unsigned len) -{ - if (h->buff && h->buff != h->inq) - kfree(h->buff); - - h->buff = kmalloc(len, GFP_NOIO); - if (!h->buff) { - h->buff = h->inq; - h->bufflen = ALUA_INQUIRY_SIZE; - return 1; - } - h->bufflen = len; - return 0; -} - /* * submit_rtpg - Issue a REPORT TARGET GROUP STATES command * @sdev: sdev the command should be sent to @@ -333,8 +315,8 @@ static int alua_check_sense(struct scsi_device *sdev, static int alua_rtpg(struct scsi_device *sdev, struct alua_dh_data *h, int wait_for_transition) { 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; @@ -345,14 +327,19 @@ static int alua_rtpg(struct scsi_device *sdev, struct alua_dh_data *h, int wait_ else expiry = round_jiffies_up(jiffies + h->transition_tmo * HZ); + buff = kzalloc(bufflen, GFP_KERNEL); + if (!buff) + return SCSI_DH_DEV_TEMP_BUSY; + retry: - retval = submit_rtpg(sdev, h->buff, h->bufflen, &sense_hdr, h->flags); + retval = submit_rtpg(sdev, buff, bufflen, &sense_hdr, h->flags); if (retval) { if (!scsi_sense_valid(&sense_hdr)) { sdev_printk(KERN_INFO, sdev, "%s: rtpg failed, result %d\n", ALUA_DH_NAME, retval); + kfree(buff); if (driver_byte(retval) == DRIVER_ERROR) return SCSI_DH_DEV_TEMP_BUSY; return SCSI_DH_IO; @@ -390,14 +377,18 @@ static int alua_rtpg(struct scsi_device *sdev, struct alua_dh_data *h, int wait_ 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(&h->buff[0]) + 4; + len = get_unaligned_be32(&buff[0]) + 4; - if (len > h->bufflen) { + if (len > bufflen) { /* Resubmit with the correct length */ - if (realloc_buffer(h, 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 */ @@ -407,24 +398,25 @@ static int alua_rtpg(struct scsi_device *sdev, struct alua_dh_data *h, int wait_ } orig_transition_tmo = h->transition_tmo; - if ((h->buff[4] & RTPG_FMT_MASK) == RTPG_FMT_EXT_HDR && h->buff[5] != 0) - h->transition_tmo = h->buff[5]; + if ((buff[4] & RTPG_FMT_MASK) == RTPG_FMT_EXT_HDR && buff[5] != 0) + h->transition_tmo = buff[5]; else h->transition_tmo = ALUA_FAILOVER_TIMEOUT; - if (wait_for_transition && (orig_transition_tmo != h->transition_tmo)) { + if (wait_for_transition && + (orig_transition_tmo != h->transition_tmo)) { sdev_printk(KERN_INFO, sdev, "%s: transition timeout set to %d seconds\n", ALUA_DH_NAME, h->transition_tmo); expiry = jiffies + h->transition_tmo * HZ; } - if ((h->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 = h->buff + tpg_desc_tbl_off; + for (k = tpg_desc_tbl_off, ucp = buff + tpg_desc_tbl_off; k < len; k += off, ucp += off) { @@ -474,6 +466,7 @@ static int alua_rtpg(struct scsi_device *sdev, struct alua_dh_data *h, int wait_ err = SCSI_DH_OK; break; } + kfree(buff); return err; } @@ -668,8 +661,6 @@ static int alua_bus_attach(struct scsi_device *sdev) h->state = TPGS_STATE_OPTIMIZED; h->group_id = -1; h->rel_port = -1; - h->buff = h->inq; - h->bufflen = ALUA_INQUIRY_SIZE; h->sdev = sdev; err = alua_initialize(sdev, h); @@ -691,8 +682,6 @@ static void alua_bus_detach(struct scsi_device *sdev) { struct alua_dh_data *h = sdev->handler_data; - if (h->buff && h->inq != h->buff) - kfree(h->buff); sdev->handler_data = NULL; kfree(h); } -- 2.7.4