From 9b80dcec411e8937d94d7ca09da08ed6ca95e6ba Mon Sep 17 00:00:00 2001 From: Hannes Reinecke Date: Tue, 1 Dec 2015 10:16:44 +0100 Subject: [PATCH] scsi_dh_alua: Use vpd_pg83 information The SCSI device now has the VPD page 0x83 information attached, so there is no need to query it again. [mkp: Fixed a checkpatch warning] Signed-off-by: Hannes Reinecke Reviewed-by: Martin K. Petersen Reviewed-by: Christoph Hellwig Reviewed-by: Johannes Thumshirn Signed-off-by: Martin K. Petersen --- drivers/scsi/device_handler/scsi_dh_alua.c | 87 +++++----------------- 1 file changed, 18 insertions(+), 69 deletions(-) diff --git a/drivers/scsi/device_handler/scsi_dh_alua.c b/drivers/scsi/device_handler/scsi_dh_alua.c index 7d01ef0b66cc..87c5ba86aff2 100644 --- a/drivers/scsi/device_handler/scsi_dh_alua.c +++ b/drivers/scsi/device_handler/scsi_dh_alua.c @@ -130,43 +130,6 @@ static struct request *get_alua_req(struct scsi_device *sdev, return rq; } -/* - * submit_vpd_inquiry - Issue an INQUIRY VPD page 0x83 command - * @sdev: sdev the command should be sent to - */ -static int submit_vpd_inquiry(struct scsi_device *sdev, struct alua_dh_data *h) -{ - struct request *rq; - int err = SCSI_DH_RES_TEMP_UNAVAIL; - - rq = get_alua_req(sdev, h->buff, h->bufflen, READ); - if (!rq) - goto done; - - /* Prepare the command. */ - rq->cmd[0] = INQUIRY; - rq->cmd[1] = 1; - rq->cmd[2] = 0x83; - rq->cmd[4] = h->bufflen; - rq->cmd_len = COMMAND_SIZE(INQUIRY); - - rq->sense = h->sense; - memset(rq->sense, 0, SCSI_SENSE_BUFFERSIZE); - rq->sense_len = h->senselen = 0; - - err = blk_execute_rq(rq->q, NULL, rq, 1); - if (err == -EIO) { - sdev_printk(KERN_INFO, sdev, - "%s: evpd inquiry failed with %x\n", - ALUA_DH_NAME, rq->errors); - h->senselen = rq->sense_len; - err = SCSI_DH_IO; - } - blk_put_request(rq); -done: - return err; -} - /* * submit_rtpg - Issue a REPORT TARGET GROUP STATES command * @sdev: sdev the command should be sent to @@ -359,43 +322,29 @@ static int alua_check_tpgs(struct scsi_device *sdev, struct alua_dh_data *h) } /* - * alua_vpd_inquiry - Evaluate INQUIRY vpd page 0x83 + * alua_check_vpd - Evaluate INQUIRY vpd page 0x83 * @sdev: device to be checked * * Extract the relative target port and the target port group * descriptor from the list of identificators. */ -static int alua_vpd_inquiry(struct scsi_device *sdev, struct alua_dh_data *h) +static int alua_check_vpd(struct scsi_device *sdev, struct alua_dh_data *h) { - int len; - unsigned err; unsigned char *d; + unsigned char __rcu *vpd_pg83; - retry: - err = submit_vpd_inquiry(sdev, h); - - if (err != SCSI_DH_OK) - return err; - - /* Check if vpd page exceeds initial buffer */ - len = (h->buff[2] << 8) + h->buff[3] + 4; - if (len > h->bufflen) { - /* Resubmit with the correct length */ - if (realloc_buffer(h, len)) { - sdev_printk(KERN_WARNING, sdev, - "%s: kmalloc buffer failed\n", - ALUA_DH_NAME); - /* Temporary failure, bypass */ - return SCSI_DH_DEV_TEMP_BUSY; - } - goto retry; + rcu_read_lock(); + if (!rcu_dereference(sdev->vpd_pg83)) { + rcu_read_unlock(); + return SCSI_DH_DEV_UNSUPP; } /* - * Now look for the correct descriptor. + * Look for the correct descriptor. */ - d = h->buff + 4; - while (d < h->buff + len) { + vpd_pg83 = rcu_dereference(sdev->vpd_pg83); + d = vpd_pg83 + 4; + while (d < vpd_pg83 + sdev->vpd_pg83_len) { switch (d[1] & 0xf) { case 0x4: /* Relative target port */ @@ -410,6 +359,7 @@ static int alua_vpd_inquiry(struct scsi_device *sdev, struct alua_dh_data *h) } d += d[3] + 4; } + rcu_read_unlock(); if (h->group_id == -1) { /* @@ -422,14 +372,13 @@ static int alua_vpd_inquiry(struct scsi_device *sdev, struct alua_dh_data *h) ALUA_DH_NAME); h->state = TPGS_STATE_OPTIMIZED; h->tpgs = TPGS_MODE_NONE; - err = SCSI_DH_DEV_UNSUPP; - } else { - sdev_printk(KERN_INFO, sdev, - "%s: port group %02x rel port %02x\n", - ALUA_DH_NAME, h->group_id, h->rel_port); + return SCSI_DH_DEV_UNSUPP; } + sdev_printk(KERN_INFO, sdev, + "%s: port group %02x rel port %02x\n", + ALUA_DH_NAME, h->group_id, h->rel_port); - return err; + return 0; } static char print_alua_state(int state) @@ -692,7 +641,7 @@ static int alua_initialize(struct scsi_device *sdev, struct alua_dh_data *h) if (err != SCSI_DH_OK) goto out; - err = alua_vpd_inquiry(sdev, h); + err = alua_check_vpd(sdev, h); if (err != SCSI_DH_OK) goto out; -- 2.20.1