From 1fd106851698e9a858d20ab0e0f0afd5e9ec9332 Mon Sep 17 00:00:00 2001 From: "Yang, Bo" Date: Tue, 12 Oct 2010 07:18:50 -0600 Subject: [PATCH] [SCSI] megaraid_sas: Add input parameter for max_sectors Driver add the input parameters support for max_sectors for megaraid sas gen2 chip. Customer can set the max_sectors support to 1MB for gen2 chip during the driver load. Signed-off-by Bo Yang Signed-off-by: James Bottomley --- drivers/scsi/megaraid/megaraid_sas.c | 30 ++++++++++++++++++++++++++++ drivers/scsi/megaraid/megaraid_sas.h | 1 + 2 files changed, 31 insertions(+) diff --git a/drivers/scsi/megaraid/megaraid_sas.c b/drivers/scsi/megaraid/megaraid_sas.c index 09a455d4b6ed..41ffc205724f 100644 --- a/drivers/scsi/megaraid/megaraid_sas.c +++ b/drivers/scsi/megaraid/megaraid_sas.c @@ -56,6 +56,15 @@ module_param_named(poll_mode_io, poll_mode_io, int, 0); MODULE_PARM_DESC(poll_mode_io, "Complete cmds from IO path, (default=0)"); +/* + * Number of sectors per IO command + * Will be set in megasas_init_mfi if user does not provide + */ +static unsigned int max_sectors; +module_param_named(max_sectors, max_sectors, int, 0); +MODULE_PARM_DESC(max_sectors, + "Maximum number of sectors per IO command"); + MODULE_LICENSE("GPL"); MODULE_VERSION(MEGASAS_VERSION); MODULE_AUTHOR("megaraidlinux@lsi.com"); @@ -3586,6 +3595,27 @@ static int megasas_io_attach(struct megasas_instance *instance) instance->max_fw_cmds - MEGASAS_INT_CMDS; host->this_id = instance->init_id; host->sg_tablesize = instance->max_num_sge; + /* + * Check if the module parameter value for max_sectors can be used + */ + if (max_sectors && max_sectors < instance->max_sectors_per_req) + instance->max_sectors_per_req = max_sectors; + else { + if (max_sectors) { + if (((instance->pdev->device == + PCI_DEVICE_ID_LSI_SAS1078GEN2) || + (instance->pdev->device == + PCI_DEVICE_ID_LSI_SAS0079GEN2)) && + (max_sectors <= MEGASAS_MAX_SECTORS)) { + instance->max_sectors_per_req = max_sectors; + } else { + printk(KERN_INFO "megasas: max_sectors should be > 0" + "and <= %d (or < 1MB for GEN2 controller)\n", + instance->max_sectors_per_req); + } + } + } + host->max_sectors = instance->max_sectors_per_req; host->cmd_per_lun = 128; host->max_channel = MEGASAS_MAX_CHANNELS - 1; diff --git a/drivers/scsi/megaraid/megaraid_sas.h b/drivers/scsi/megaraid/megaraid_sas.h index 16a4f68a34b0..54d1a154b448 100644 --- a/drivers/scsi/megaraid/megaraid_sas.h +++ b/drivers/scsi/megaraid/megaraid_sas.h @@ -706,6 +706,7 @@ struct megasas_ctrl_info { #define MEGASAS_MAX_LD_IDS (MEGASAS_MAX_LD_CHANNELS * \ MEGASAS_MAX_DEV_PER_CHANNEL) +#define MEGASAS_MAX_SECTORS (2*1024) #define MEGASAS_DBG_LVL 1 #define MEGASAS_FW_BUSY 1 -- 2.34.1