From mboxrd@z Thu Jan 1 00:00:00 1970 From: jonathan.derrick@intel.com (Jon Derrick) Date: Fri, 29 May 2015 15:58:25 -0600 Subject: [PATCH] NVMe: Added IOCTL to initiate subsystem resets Message-ID: <1432936705-30232-1-git-send-email-jonathan.derrick@intel.com> 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 --- This patch is contigent on the subsystem reset detection patch: http://lists.infradead.org/pipermail/linux-nvme/2015-May/001779.html 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 0cf18c2..039e1ea 100644 --- a/drivers/block/nvme-core.c +++ b/drivers/block/nvme-core.c @@ -1846,6 +1846,15 @@ 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) { @@ -1861,6 +1870,8 @@ static int nvme_ioctl(struct block_device *bdev, fmode_t mode, unsigned int cmd, return nvme_user_cmd(ns->dev, ns, (void __user *)arg); case NVME_IOCTL_SUBMIT_IO: return nvme_submit_io(ns, (void __user *)arg); + case NVME_IOCTL_SUBSYS_RESET: + return nvme_subsys_reset(ns->dev); case SG_GET_VERSION_NUM: return nvme_sg_get_version_num((void __user *)arg); case SG_IO: diff --git a/include/linux/nvme.h b/include/linux/nvme.h index 977b0b3..35f0ece 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 aef9a81..7d2907d 100644 --- a/include/uapi/linux/nvme.h +++ b/include/uapi/linux/nvme.h @@ -579,5 +579,6 @@ struct nvme_passthru_cmd { #define NVME_IOCTL_ADMIN_CMD _IOWR('N', 0x41, struct nvme_admin_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_SUBSYS_RESET _IO('N', 0x44) #endif /* _UAPI_LINUX_NVME_H */ -- 2.1.4