nvme: use nvme_wait_ready in nvme_shutdown_ctrl

Refactor the code to wait for CSTS state changes so that it can be reused
by nvme_shutdown_ctrl.  This reduces the delay between each iteration
that checks CSTS from 100ms in the shutdown code to the 1 to 2ms range
done during enable, matching the changes from commit 3e98c2443f5c that
were only applied to the enable/disable path.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Pankaj Raghav <p.raghav@samsung.com>

diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c
index 7961e146bbb16368ed6b7810e44b2de4daf00fda..03b2e34dcf724919591289e469f61165b380a691 100644 (file)
--- a/drivers/nvme/host/core.c
+++ b/drivers/nvme/host/core.c
@@ -2252,16 +2252,17 @@ static const struct block_device_operations nvme_bdev_ops = {
        .pr_ops         = &nvme_pr_ops,
 };
 
-static int nvme_wait_ready(struct nvme_ctrl *ctrl, u32 timeout, bool enabled)
+static int nvme_wait_ready(struct nvme_ctrl *ctrl, u32 mask, u32 val,
+               u32 timeout, const char *op)
 {
-       unsigned long timeout_jiffies = ((timeout + 1) * HZ / 2) + jiffies;
-       u32 csts, bit = enabled ? NVME_CSTS_RDY : 0;
+       unsigned long timeout_jiffies = jiffies + timeout * HZ;
+       u32 csts;
        int ret;
 
        while ((ret = ctrl->ops->reg_read32(ctrl, NVME_REG_CSTS, &csts)) == 0) {
                if (csts == ~0)
                        return -ENODEV;
-               if ((csts & NVME_CSTS_RDY) == bit)
+               if ((csts & mask) == val)
                        break;
 
                usleep_range(1000, 2000);
@@ -2270,7 +2271,7 @@ static int nvme_wait_ready(struct nvme_ctrl *ctrl, u32 timeout, bool enabled)
                if (time_after(jiffies, timeout_jiffies)) {
                        dev_err(ctrl->device,
                                "Device not ready; aborting %s, CSTS=0x%x\n",
-                               enabled ? "initialisation" : "reset", csts);
+                               op, csts);
                        return -ENODEV;
                }
        }
@@ -2297,8 +2298,8 @@ int nvme_disable_ctrl(struct nvme_ctrl *ctrl)
 
        if (ctrl->quirks & NVME_QUIRK_DELAY_BEFORE_CHK_RDY)
                msleep(NVME_QUIRK_DELAY_AMOUNT);
-
-       return nvme_wait_ready(ctrl, NVME_CAP_TIMEOUT(ctrl->cap), false);
+       return nvme_wait_ready(ctrl, NVME_CSTS_RDY, 0,
+                              (NVME_CAP_TIMEOUT(ctrl->cap) + 1) / 2, "reset");
 }
 EXPORT_SYMBOL_GPL(nvme_disable_ctrl);
 
@@ -2363,14 +2364,13 @@ int nvme_enable_ctrl(struct nvme_ctrl *ctrl)
        ret = ctrl->ops->reg_write32(ctrl, NVME_REG_CC, ctrl->ctrl_config);
        if (ret)
                return ret;
-       return nvme_wait_ready(ctrl, timeout, true);
+       return nvme_wait_ready(ctrl, NVME_CSTS_RDY, NVME_CSTS_RDY,
+                              (timeout + 1) / 2, "initialisation");
 }
 EXPORT_SYMBOL_GPL(nvme_enable_ctrl);
 
 int nvme_shutdown_ctrl(struct nvme_ctrl *ctrl)
 {
-       unsigned long timeout = jiffies + (ctrl->shutdown_timeout * HZ);
-       u32 csts;
        int ret;
 
        ctrl->ctrl_config &= ~NVME_CC_SHN_MASK;
@@ -2379,22 +2379,8 @@ int nvme_shutdown_ctrl(struct nvme_ctrl *ctrl)
        ret = ctrl->ops->reg_write32(ctrl, NVME_REG_CC, ctrl->ctrl_config);
        if (ret)
                return ret;
-
-       while ((ret = ctrl->ops->reg_read32(ctrl, NVME_REG_CSTS, &csts)) == 0) {
-               if ((csts & NVME_CSTS_SHST_MASK) == NVME_CSTS_SHST_CMPLT)
-                       break;
-
-               msleep(100);
-               if (fatal_signal_pending(current))
-                       return -EINTR;
-               if (time_after(jiffies, timeout)) {
-                       dev_err(ctrl->device,
-                               "Device shutdown incomplete; abort shutdown\n");
-                       return -ENODEV;
-               }
-       }
-
-       return ret;
+       return nvme_wait_ready(ctrl, NVME_CSTS_SHST_MASK, NVME_CSTS_SHST_CMPLT,
+                              ctrl->shutdown_timeout, "shutdown");
 }
 EXPORT_SYMBOL_GPL(nvme_shutdown_ctrl);