From 015487b89f27d91d95a056cdc3c85e6c729bff12 Mon Sep 17 00:00:00 2001 From: Roland Dreier Date: Mon, 13 Feb 2012 16:18:17 -0800 Subject: [PATCH] target: Untangle front-end and back-end meanings of max_sectors attribute se_dev_attrib.max_sectors currently has two independent meanings: - It is reported in the block limits VPD page as the maximum transfer length, ie the largest IO that the front-end (fabric) can handle. Also the target core doesn't enforce this maximum transfer length. - It is used to hold the size of the largest IO that the back-end can handle, so we know when to split SCSI commands into multiple tasks. Fix this by adding a new se_dev_attrib.fabric_max_sectors to hold the maximum transfer length, and checking incoming IOs against that limit. Signed-off-by: Roland Dreier Signed-off-by: Nicholas Bellinger --- drivers/target/target_core_cdb.c | 2 +- drivers/target/target_core_configfs.c | 4 +++ drivers/target/target_core_device.c | 65 ++++++++++++++++++++++++++++++---- drivers/target/target_core_internal.h | 1 + drivers/target/target_core_transport.c | 8 +++++ include/target/target_core_base.h | 3 ++ 6 files changed, 76 insertions(+), 7 deletions(-) diff --git a/drivers/target/target_core_cdb.c b/drivers/target/target_core_cdb.c index 4f65b25..41ca2d4 100644 --- a/drivers/target/target_core_cdb.c +++ b/drivers/target/target_core_cdb.c @@ -456,7 +456,7 @@ target_emulate_evpd_b0(struct se_cmd *cmd, unsigned char *buf) /* * Set MAXIMUM TRANSFER LENGTH */ - put_unaligned_be32(dev->se_sub_dev->se_dev_attrib.max_sectors, &buf[8]); + put_unaligned_be32(dev->se_sub_dev->se_dev_attrib.fabric_max_sectors, &buf[8]); /* * Set OPTIMAL TRANSFER LENGTH diff --git a/drivers/target/target_core_configfs.c b/drivers/target/target_core_configfs.c index 0700d3b..ac0ee50 100644 --- a/drivers/target/target_core_configfs.c +++ b/drivers/target/target_core_configfs.c @@ -702,6 +702,9 @@ SE_DEV_ATTR_RO(hw_max_sectors); DEF_DEV_ATTRIB(max_sectors); SE_DEV_ATTR(max_sectors, S_IRUGO | S_IWUSR); +DEF_DEV_ATTRIB(fabric_max_sectors); +SE_DEV_ATTR(fabric_max_sectors, S_IRUGO | S_IWUSR); + DEF_DEV_ATTRIB(optimal_sectors); SE_DEV_ATTR(optimal_sectors, S_IRUGO | S_IWUSR); @@ -741,6 +744,7 @@ static struct configfs_attribute *target_core_dev_attrib_attrs[] = { &target_core_dev_attrib_block_size.attr, &target_core_dev_attrib_hw_max_sectors.attr, &target_core_dev_attrib_max_sectors.attr, + &target_core_dev_attrib_fabric_max_sectors.attr, &target_core_dev_attrib_optimal_sectors.attr, &target_core_dev_attrib_hw_queue_depth.attr, &target_core_dev_attrib_queue_depth.attr, diff --git a/drivers/target/target_core_device.c b/drivers/target/target_core_device.c index 0b25b50..27da4e4 100644 --- a/drivers/target/target_core_device.c +++ b/drivers/target/target_core_device.c @@ -889,10 +889,15 @@ void se_dev_set_default_attribs( limits->logical_block_size); dev->se_sub_dev->se_dev_attrib.max_sectors = limits->max_sectors; /* - * Set optimal_sectors from max_sectors, which can be lowered via - * configfs. + * Set fabric_max_sectors, which is reported in block limits + * VPD page (B0h). */ - dev->se_sub_dev->se_dev_attrib.optimal_sectors = limits->max_sectors; + dev->se_sub_dev->se_dev_attrib.fabric_max_sectors = DA_FABRIC_MAX_SECTORS; + /* + * Set optimal_sectors from fabric_max_sectors, which can be + * lowered via configfs. + */ + dev->se_sub_dev->se_dev_attrib.optimal_sectors = DA_FABRIC_MAX_SECTORS; /* * queue_depth is based on subsystem plugin dependent requirements. */ @@ -1224,6 +1229,54 @@ int se_dev_set_max_sectors(struct se_device *dev, u32 max_sectors) return 0; } +int se_dev_set_fabric_max_sectors(struct se_device *dev, u32 fabric_max_sectors) +{ + if (atomic_read(&dev->dev_export_obj.obj_access_count)) { + pr_err("dev[%p]: Unable to change SE Device" + " fabric_max_sectors while dev_export_obj: %d count exists\n", + dev, atomic_read(&dev->dev_export_obj.obj_access_count)); + return -EINVAL; + } + if (!fabric_max_sectors) { + pr_err("dev[%p]: Illegal ZERO value for" + " fabric_max_sectors\n", dev); + return -EINVAL; + } + if (fabric_max_sectors < DA_STATUS_MAX_SECTORS_MIN) { + pr_err("dev[%p]: Passed fabric_max_sectors: %u less than" + " DA_STATUS_MAX_SECTORS_MIN: %u\n", dev, fabric_max_sectors, + DA_STATUS_MAX_SECTORS_MIN); + return -EINVAL; + } + if (dev->transport->transport_type == TRANSPORT_PLUGIN_PHBA_PDEV) { + if (fabric_max_sectors > dev->se_sub_dev->se_dev_attrib.hw_max_sectors) { + pr_err("dev[%p]: Passed fabric_max_sectors: %u" + " greater than TCM/SE_Device max_sectors:" + " %u\n", dev, fabric_max_sectors, + dev->se_sub_dev->se_dev_attrib.hw_max_sectors); + return -EINVAL; + } + } else { + if (fabric_max_sectors > DA_STATUS_MAX_SECTORS_MAX) { + pr_err("dev[%p]: Passed fabric_max_sectors: %u" + " greater than DA_STATUS_MAX_SECTORS_MAX:" + " %u\n", dev, fabric_max_sectors, + DA_STATUS_MAX_SECTORS_MAX); + return -EINVAL; + } + } + /* + * Align max_sectors down to PAGE_SIZE to follow transport_allocate_data_tasks() + */ + fabric_max_sectors = se_dev_align_max_sectors(fabric_max_sectors, + dev->se_sub_dev->se_dev_attrib.block_size); + + dev->se_sub_dev->se_dev_attrib.fabric_max_sectors = fabric_max_sectors; + pr_debug("dev[%p]: SE Device max_sectors changed to %u\n", + dev, fabric_max_sectors); + return 0; +} + int se_dev_set_optimal_sectors(struct se_device *dev, u32 optimal_sectors) { if (atomic_read(&dev->dev_export_obj.obj_access_count)) { @@ -1237,10 +1290,10 @@ int se_dev_set_optimal_sectors(struct se_device *dev, u32 optimal_sectors) " changed for TCM/pSCSI\n", dev); return -EINVAL; } - if (optimal_sectors > dev->se_sub_dev->se_dev_attrib.max_sectors) { + if (optimal_sectors > dev->se_sub_dev->se_dev_attrib.fabric_max_sectors) { pr_err("dev[%p]: Passed optimal_sectors %u cannot be" - " greater than max_sectors: %u\n", dev, - optimal_sectors, dev->se_sub_dev->se_dev_attrib.max_sectors); + " greater than fabric_max_sectors: %u\n", dev, + optimal_sectors, dev->se_sub_dev->se_dev_attrib.fabric_max_sectors); return -EINVAL; } diff --git a/drivers/target/target_core_internal.h b/drivers/target/target_core_internal.h index b026ded..21c0563 100644 --- a/drivers/target/target_core_internal.h +++ b/drivers/target/target_core_internal.h @@ -53,6 +53,7 @@ int se_dev_set_is_nonrot(struct se_device *, int); int se_dev_set_emulate_rest_reord(struct se_device *dev, int); int se_dev_set_queue_depth(struct se_device *, u32); int se_dev_set_max_sectors(struct se_device *, u32); +int se_dev_set_fabric_max_sectors(struct se_device *, u32); int se_dev_set_optimal_sectors(struct se_device *, u32); int se_dev_set_block_size(struct se_device *, u32); struct se_lun *core_dev_add_lun(struct se_portal_group *, struct se_hba *, diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c index 19804b6..b79c6a2 100644 --- a/drivers/target/target_core_transport.c +++ b/drivers/target/target_core_transport.c @@ -37,6 +37,7 @@ #include #include #include +#include #include #include #include @@ -3107,6 +3108,13 @@ static int transport_generic_cmd_sequencer( cmd->data_length = size; } + if (cmd->se_cmd_flags & SCF_SCSI_DATA_SG_IO_CDB && + sectors > dev->se_sub_dev->se_dev_attrib.fabric_max_sectors) { + printk_ratelimited(KERN_ERR "SCSI OP %02xh with too big sectors %u\n", + cdb[0], sectors); + goto out_invalid_cdb_field; + } + /* reject any command that we don't have a handler for */ if (!(passthrough || cmd->execute_task || (cmd->se_cmd_flags & SCF_SCSI_DATA_SG_IO_CDB))) diff --git a/include/target/target_core_base.h b/include/target/target_core_base.h index 99d7373..1641dea 100644 --- a/include/target/target_core_base.h +++ b/include/target/target_core_base.h @@ -86,6 +86,8 @@ #define DA_UNMAP_GRANULARITY_DEFAULT 0 /* Default unmap_granularity_alignment */ #define DA_UNMAP_GRANULARITY_ALIGNMENT_DEFAULT 0 +/* Default max transfer length */ +#define DA_FABRIC_MAX_SECTORS 8192 /* Emulation for Direct Page Out */ #define DA_EMULATE_DPO 0 /* Emulation for Forced Unit Access WRITEs */ @@ -726,6 +728,7 @@ struct se_dev_attrib { u32 block_size; u32 hw_max_sectors; u32 max_sectors; + u32 fabric_max_sectors; u32 optimal_sectors; u32 hw_queue_depth; u32 queue_depth; -- 2.7.4