From 81f03fedcce7ee7e83c37237ecaa2f68aad236fd Mon Sep 17 00:00:00 2001 From: Jon Derrick Date: Mon, 10 Aug 2015 15:20:41 -0600 Subject: [PATCH] NVMe: Add nvme subsystem reset IOCTL Controllers can perform optional subsystem resets as introduced in NVMe 1.1. This patch adds an IOCTL to trigger the subsystem reset by writing "NVMe" to the NSSR register. Signed-off-by: Jon Derrick Acked-by: Keith Busch Signed-off-by: Jens Axboe --- drivers/block/nvme-core.c | 11 +++++++++++ include/linux/nvme.h | 2 +- include/uapi/linux/nvme.h | 1 + 3 files changed, 13 insertions(+), 1 deletion(-) diff --git a/drivers/block/nvme-core.c b/drivers/block/nvme-core.c index e318a992e2e6..3a35c5807bb7 100644 --- a/drivers/block/nvme-core.c +++ b/drivers/block/nvme-core.c @@ -1901,6 +1901,15 @@ static int nvme_user_cmd(struct nvme_dev *dev, struct nvme_ns *ns, return status; } +static int nvme_subsys_reset(struct nvme_dev *dev) +{ + if (!dev->subsystem) + return -ENOTTY; + + writel(0x4E564D65, &dev->bar->nssr); /* "NVMe" */ + return 0; +} + static int nvme_ioctl(struct block_device *bdev, fmode_t mode, unsigned int cmd, unsigned long arg) { @@ -2932,6 +2941,8 @@ static long nvme_dev_ioctl(struct file *f, unsigned int cmd, unsigned long arg) case NVME_IOCTL_RESET: dev_warn(dev->dev, "resetting controller\n"); return nvme_reset(dev); + case NVME_IOCTL_SUBSYS_RESET: + return nvme_subsys_reset(dev); default: return -ENOTTY; } diff --git a/include/linux/nvme.h b/include/linux/nvme.h index d6b5600cfa47..b5812c395351 100644 --- a/include/linux/nvme.h +++ b/include/linux/nvme.h @@ -28,7 +28,7 @@ struct nvme_bar { __u32 cc; /* Controller Configuration */ __u32 rsvd1; /* Reserved */ __u32 csts; /* Controller Status */ - __u32 rsvd2; /* Reserved */ + __u32 nssr; /* Subsystem Reset */ __u32 aqa; /* Admin Queue Attributes */ __u64 asq; /* Admin SQ Base Address */ __u64 acq; /* Admin CQ Base Address */ diff --git a/include/uapi/linux/nvme.h b/include/uapi/linux/nvme.h index 732b32e92b02..8864194a4151 100644 --- a/include/uapi/linux/nvme.h +++ b/include/uapi/linux/nvme.h @@ -584,5 +584,6 @@ struct nvme_passthru_cmd { #define NVME_IOCTL_SUBMIT_IO _IOW('N', 0x42, struct nvme_user_io) #define NVME_IOCTL_IO_CMD _IOWR('N', 0x43, struct nvme_passthru_cmd) #define NVME_IOCTL_RESET _IO('N', 0x44) +#define NVME_IOCTL_SUBSYS_RESET _IO('N', 0x45) #endif /* _UAPI_LINUX_NVME_H */ -- 2.39.5