diff options
| -rw-r--r-- | drivers/target/target_core_device.c | 6 | ||||
| -rw-r--r-- | drivers/target/target_core_iblock.c | 31 | ||||
| -rw-r--r-- | drivers/target/target_core_spc.c | 21 | ||||
| -rw-r--r-- | include/target/target_core_backend.h | 1 |
4 files changed, 48 insertions, 11 deletions
diff --git a/drivers/target/target_core_device.c b/drivers/target/target_core_device.c index f2aa7543d20a..d10cbed23472 100644 --- a/drivers/target/target_core_device.c +++ b/drivers/target/target_core_device.c @@ -772,6 +772,12 @@ int se_dev_set_emulate_write_cache(struct se_device *dev, int flag) pr_err("emulate_write_cache not supported for pSCSI\n"); return -EINVAL; } + if (dev->transport->get_write_cache) { + pr_warn("emulate_write_cache cannot be changed when underlying" + " HW reports WriteCacheEnabled, ignoring request\n"); + return 0; + } + dev->dev_attrib.emulate_write_cache = flag; pr_debug("dev[%p]: SE Device WRITE_CACHE_EMULATION flag: %d\n", dev, dev->dev_attrib.emulate_write_cache); diff --git a/drivers/target/target_core_iblock.c b/drivers/target/target_core_iblock.c index b526d23dcd4f..2f74e17ad3e6 100644 --- a/drivers/target/target_core_iblock.c +++ b/drivers/target/target_core_iblock.c @@ -154,6 +154,7 @@ static int iblock_configure_device(struct se_device *dev) if (blk_queue_nonrot(q)) dev->dev_attrib.is_nonrot = 1; + return 0; out_free_bioset: @@ -654,20 +655,24 @@ iblock_execute_rw(struct se_cmd *cmd) u32 sg_num = sgl_nents; sector_t block_lba; unsigned bio_cnt; - int rw; + int rw = 0; int i; if (data_direction == DMA_TO_DEVICE) { + struct iblock_dev *ib_dev = IBLOCK_DEV(dev); + struct request_queue *q = bdev_get_queue(ib_dev->ibd_bd); /* - * Force data to disk if we pretend to not have a volatile - * write cache, or the initiator set the Force Unit Access bit. + * Force writethrough using WRITE_FUA if a volatile write cache + * is not enabled, or if initiator set the Force Unit Access bit. */ - if (dev->dev_attrib.emulate_write_cache == 0 || - (dev->dev_attrib.emulate_fua_write > 0 && - (cmd->se_cmd_flags & SCF_FUA))) - rw = WRITE_FUA; - else + if (q->flush_flags & REQ_FUA) { + if (cmd->se_cmd_flags & SCF_FUA) + rw = WRITE_FUA; + else if (!(q->flush_flags & REQ_FLUSH)) + rw = WRITE_FUA; + } else { rw = WRITE; + } } else { rw = READ; } @@ -774,6 +779,15 @@ iblock_parse_cdb(struct se_cmd *cmd) return sbc_parse_cdb(cmd, &iblock_sbc_ops); } +bool iblock_get_write_cache(struct se_device *dev) +{ + struct iblock_dev *ib_dev = IBLOCK_DEV(dev); + struct block_device *bd = ib_dev->ibd_bd; + struct request_queue *q = bdev_get_queue(bd); + + return q->flush_flags & REQ_FLUSH; +} + static struct se_subsystem_api iblock_template = { .name = "iblock", .inquiry_prod = "IBLOCK", @@ -790,6 +804,7 @@ static struct se_subsystem_api iblock_template = { .show_configfs_dev_params = iblock_show_configfs_dev_params, .get_device_type = sbc_get_device_type, .get_blocks = iblock_get_blocks, + .get_write_cache = iblock_get_write_cache, }; static int __init iblock_module_init(void) diff --git a/drivers/target/target_core_spc.c b/drivers/target/target_core_spc.c index fa2447004006..803339516fb9 100644 --- a/drivers/target/target_core_spc.c +++ b/drivers/target/target_core_spc.c @@ -407,16 +407,31 @@ check_scsi_name: } EXPORT_SYMBOL(spc_emulate_evpd_83); +static bool +spc_check_dev_wce(struct se_device *dev) +{ + bool wce = false; + + if (dev->transport->get_write_cache) + wce = dev->transport->get_write_cache(dev); + else if (dev->dev_attrib.emulate_write_cache > 0) + wce = true; + + return wce; +} + /* Extended INQUIRY Data VPD Page */ static sense_reason_t spc_emulate_evpd_86(struct se_cmd *cmd, unsigned char *buf) { + struct se_device *dev = cmd->se_dev; + buf[3] = 0x3c; /* Set HEADSUP, ORDSUP, SIMPSUP */ buf[5] = 0x07; /* If WriteCache emulation is enabled, set V_SUP */ - if (cmd->se_dev->dev_attrib.emulate_write_cache > 0) + if (spc_check_dev_wce(dev)) buf[6] = 0x01; return 0; } @@ -766,7 +781,7 @@ static int spc_modesense_caching(struct se_device *dev, u8 pc, u8 *p) if (pc == 1) goto out; - if (dev->dev_attrib.emulate_write_cache > 0) + if (spc_check_dev_wce(dev)) p[2] = 0x04; /* Write Cache Enable */ p[12] = 0x20; /* Disabled Read Ahead */ @@ -878,7 +893,7 @@ static sense_reason_t spc_emulate_modesense(struct se_cmd *cmd) (cmd->se_deve->lun_flags & TRANSPORT_LUNFLAGS_READ_ONLY))) spc_modesense_write_protect(&buf[length], type); - if ((dev->dev_attrib.emulate_write_cache > 0) && + if ((spc_check_dev_wce(dev)) && (dev->dev_attrib.emulate_fua_write > 0)) spc_modesense_dpofua(&buf[length], type); diff --git a/include/target/target_core_backend.h b/include/target/target_core_backend.h index 819b0fc45215..f9a80169775d 100644 --- a/include/target/target_core_backend.h +++ b/include/target/target_core_backend.h @@ -35,6 +35,7 @@ struct se_subsystem_api { u32 (*get_device_type)(struct se_device *); sector_t (*get_blocks)(struct se_device *); unsigned char *(*get_sense_buffer)(struct se_cmd *); + bool (*get_write_cache)(struct se_device *); }; struct sbc_ops { |
