From f783f444ceaa7eab043a7a5ae0e34c68743c0358 Mon Sep 17 00:00:00 2001 From: Logan Gunthorpe Date: Fri, 24 Jul 2020 11:25:15 -0600 Subject: nvme: introduce nvme_ctrl_get_by_path() nvme_ctrl_get_by_path() is analogous to blkdev_get_by_path() except it gets a struct nvme_ctrl from the path to its char dev (/dev/nvme0). It makes use of filp_open() to open the file and uses the private data to obtain a pointer to the struct nvme_ctrl. If the fops of the file do not match, -EINVAL is returned. The purpose of this function is to support NVMe-OF target passthru and is exported under the NVME_TARGET_PASSTHRU namespace. Signed-off-by: Logan Gunthorpe Reviewed-by: Keith Busch Reviewed-by: Sagi Grimberg Reviewed-by: Max Gurtovoy Signed-off-by: Christoph Hellwig --- drivers/nvme/host/core.c | 23 +++++++++++++++++++++++ drivers/nvme/host/nvme.h | 1 + 2 files changed, 24 insertions(+) (limited to 'drivers/nvme') diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c index 8296c1248f87..c44316c5018f 100644 --- a/drivers/nvme/host/core.c +++ b/drivers/nvme/host/core.c @@ -4590,6 +4590,29 @@ void nvme_sync_queues(struct nvme_ctrl *ctrl) } EXPORT_SYMBOL_GPL(nvme_sync_queues); +struct nvme_ctrl *nvme_ctrl_get_by_path(const char *path) +{ + struct nvme_ctrl *ctrl; + struct file *f; + + f = filp_open(path, O_RDWR, 0); + if (IS_ERR(f)) + return ERR_CAST(f); + + if (f->f_op != &nvme_dev_fops) { + ctrl = ERR_PTR(-EINVAL); + goto out_close; + } + + ctrl = f->private_data; + nvme_get_ctrl(ctrl); + +out_close: + filp_close(f, NULL); + return ctrl; +} +EXPORT_SYMBOL_NS_GPL(nvme_ctrl_get_by_path, NVME_TARGET_PASSTHRU); + /* * Check we didn't inadvertently grow the command structure sizes: */ diff --git a/drivers/nvme/host/nvme.h b/drivers/nvme/host/nvme.h index 4e3bc4b66c57..5af59a9bac53 100644 --- a/drivers/nvme/host/nvme.h +++ b/drivers/nvme/host/nvme.h @@ -793,5 +793,6 @@ static inline void nvme_hwmon_init(struct nvme_ctrl *ctrl) { } u32 nvme_command_effects(struct nvme_ctrl *ctrl, struct nvme_ns *ns, u8 opcode); void nvme_execute_passthru_rq(struct request *rq); +struct nvme_ctrl *nvme_ctrl_get_by_path(const char *path); #endif /* _NVME_H */ -- cgit v1.2.3