NVMe: Configure support for block flush

This configures an nvme request_queue as flush capable if the device
has a volatile write cache present.

Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>

diff --git a/drivers/block/nvme-core.c b/drivers/block/nvme-core.c
index 025dd4c..e7c4fdb 100644 (file)
--- a/drivers/block/nvme-core.c
+++ b/drivers/block/nvme-core.c
@@ -1897,6 +1897,8 @@ static struct nvme_ns *nvme_alloc_ns(struct nvme_dev *dev, unsigned nsid,
        blk_queue_logical_block_size(ns->queue, 1 << ns->lba_shift);
        if (dev->max_hw_sectors)
                blk_queue_max_hw_sectors(ns->queue, dev->max_hw_sectors);
+       if (dev->vwc & NVME_CTRL_VWC_PRESENT)
+               blk_queue_flush(ns->queue, REQ_FLUSH | REQ_FUA);
 
        disk->major = nvme_major;
        disk->first_minor = 0;
@@ -2201,6 +2203,7 @@ static int nvme_dev_add(struct nvme_dev *dev)
        nn = le32_to_cpup(&ctrl->nn);
        dev->oncs = le16_to_cpup(&ctrl->oncs);
        dev->abort_limit = ctrl->acl + 1;
+       dev->vwc = ctrl->vwc;
        memcpy(dev->serial, ctrl->sn, sizeof(ctrl->sn));
        memcpy(dev->model, ctrl->mn, sizeof(ctrl->mn));
        memcpy(dev->firmware_rev, ctrl->fr, sizeof(ctrl->fr));

diff --git a/include/linux/nvme.h b/include/linux/nvme.h
index cfd084c..6266373 100644 (file)
--- a/include/linux/nvme.h
+++ b/include/linux/nvme.h
@@ -99,6 +99,7 @@ struct nvme_dev {
        u32 stripe_size;
        u16 oncs;
        u16 abort_limit;
+       u8 vwc;
        u8 initialized;
 };
 

diff --git a/include/uapi/linux/nvme.h b/include/uapi/linux/nvme.h
index ad9014e..f090336 100644 (file)
--- a/include/uapi/linux/nvme.h
+++ b/include/uapi/linux/nvme.h
@@ -73,6 +73,7 @@ enum {
        NVME_CTRL_ONCS_COMPARE                  = 1 << 0,
        NVME_CTRL_ONCS_WRITE_UNCORRECTABLE      = 1 << 1,
        NVME_CTRL_ONCS_DSM                      = 1 << 2,
+       NVME_CTRL_VWC_PRESENT                   = 1 << 0,
 };
 
 struct nvme_lbaf {