linux_dsm_epyc7002/drivers/nvme/host/nvme.h
Keith Busch 0ff9d4e1a2 NVMe: Short-cut removal on surprise hot-unplug
This patch adds a new state that when set has the core automatically
kill request queues prior to removing namespaces.

If PCI device is not present at the time the nvme driver's remove is
called, we can kill all IO queues immediately instead of waiting for
the watchdog thread to do that at its polling interval. This improves
scenarios where multiple hot plug events occur at the same time since
it doesn't block the pci enumeration for as long.

Signed-off-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-05-17 17:14:21 -06:00

288 lines
7.6 KiB
C

/*
* Copyright (c) 2011-2014, Intel Corporation.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*/
#ifndef _NVME_H
#define _NVME_H
#include <linux/nvme.h>
#include <linux/pci.h>
#include <linux/kref.h>
#include <linux/blk-mq.h>
enum {
/*
* Driver internal status code for commands that were cancelled due
* to timeouts or controller shutdown. The value is negative so
* that it a) doesn't overlap with the unsigned hardware error codes,
* and b) can easily be tested for.
*/
NVME_SC_CANCELLED = -EINTR,
};
extern unsigned char nvme_io_timeout;
#define NVME_IO_TIMEOUT (nvme_io_timeout * HZ)
extern unsigned char admin_timeout;
#define ADMIN_TIMEOUT (admin_timeout * HZ)
extern unsigned char shutdown_timeout;
#define SHUTDOWN_TIMEOUT (shutdown_timeout * HZ)
enum {
NVME_NS_LBA = 0,
NVME_NS_LIGHTNVM = 1,
};
/*
* List of workarounds for devices that required behavior not specified in
* the standard.
*/
enum nvme_quirks {
/*
* Prefers I/O aligned to a stripe size specified in a vendor
* specific Identify field.
*/
NVME_QUIRK_STRIPE_SIZE = (1 << 0),
/*
* The controller doesn't handle Identify value others than 0 or 1
* correctly.
*/
NVME_QUIRK_IDENTIFY_CNS = (1 << 1),
/*
* The controller deterministically returns O's on reads to discarded
* logical blocks.
*/
NVME_QUIRK_DISCARD_ZEROES = (1 << 2),
};
enum nvme_ctrl_state {
NVME_CTRL_NEW,
NVME_CTRL_LIVE,
NVME_CTRL_RESETTING,
NVME_CTRL_DELETING,
NVME_CTRL_DEAD,
};
struct nvme_ctrl {
enum nvme_ctrl_state state;
spinlock_t lock;
const struct nvme_ctrl_ops *ops;
struct request_queue *admin_q;
struct device *dev;
struct kref kref;
int instance;
struct blk_mq_tag_set *tagset;
struct list_head namespaces;
struct mutex namespaces_mutex;
struct device *device; /* char device */
struct list_head node;
struct ida ns_ida;
char name[12];
char serial[20];
char model[40];
char firmware_rev[8];
u16 cntlid;
u32 ctrl_config;
u32 page_size;
u32 max_hw_sectors;
u32 stripe_size;
u16 oncs;
u16 vid;
atomic_t abort_limit;
u8 event_limit;
u8 vwc;
u32 vs;
bool subsystem;
unsigned long quirks;
struct work_struct scan_work;
struct work_struct async_event_work;
};
/*
* An NVM Express namespace is equivalent to a SCSI LUN
*/
struct nvme_ns {
struct list_head list;
struct nvme_ctrl *ctrl;
struct request_queue *queue;
struct gendisk *disk;
struct kref kref;
int instance;
u8 eui[8];
u8 uuid[16];
unsigned ns_id;
int lba_shift;
u16 ms;
bool ext;
u8 pi_type;
int type;
unsigned long flags;
#define NVME_NS_REMOVING 0
#define NVME_NS_DEAD 1
u64 mode_select_num_blocks;
u32 mode_select_block_len;
};
struct nvme_ctrl_ops {
struct module *module;
int (*reg_read32)(struct nvme_ctrl *ctrl, u32 off, u32 *val);
int (*reg_write32)(struct nvme_ctrl *ctrl, u32 off, u32 val);
int (*reg_read64)(struct nvme_ctrl *ctrl, u32 off, u64 *val);
int (*reset_ctrl)(struct nvme_ctrl *ctrl);
void (*free_ctrl)(struct nvme_ctrl *ctrl);
void (*post_scan)(struct nvme_ctrl *ctrl);
void (*submit_async_event)(struct nvme_ctrl *ctrl, int aer_idx);
};
static inline bool nvme_ctrl_ready(struct nvme_ctrl *ctrl)
{
u32 val = 0;
if (ctrl->ops->reg_read32(ctrl, NVME_REG_CSTS, &val))
return false;
return val & NVME_CSTS_RDY;
}
static inline int nvme_reset_subsystem(struct nvme_ctrl *ctrl)
{
if (!ctrl->subsystem)
return -ENOTTY;
return ctrl->ops->reg_write32(ctrl, NVME_REG_NSSR, 0x4E564D65);
}
static inline u64 nvme_block_nr(struct nvme_ns *ns, sector_t sector)
{
return (sector >> (ns->lba_shift - 9));
}
static inline unsigned nvme_map_len(struct request *rq)
{
if (rq->cmd_flags & REQ_DISCARD)
return sizeof(struct nvme_dsm_range);
else
return blk_rq_bytes(rq);
}
static inline void nvme_cleanup_cmd(struct request *req)
{
if (req->cmd_flags & REQ_DISCARD)
kfree(req->completion_data);
}
static inline int nvme_error_status(u16 status)
{
switch (status & 0x7ff) {
case NVME_SC_SUCCESS:
return 0;
case NVME_SC_CAP_EXCEEDED:
return -ENOSPC;
default:
return -EIO;
}
}
static inline bool nvme_req_needs_retry(struct request *req, u16 status)
{
return !(status & NVME_SC_DNR || blk_noretry_request(req)) &&
(jiffies - req->start_time) < req->timeout;
}
bool nvme_change_ctrl_state(struct nvme_ctrl *ctrl,
enum nvme_ctrl_state new_state);
int nvme_disable_ctrl(struct nvme_ctrl *ctrl, u64 cap);
int nvme_enable_ctrl(struct nvme_ctrl *ctrl, u64 cap);
int nvme_shutdown_ctrl(struct nvme_ctrl *ctrl);
int nvme_init_ctrl(struct nvme_ctrl *ctrl, struct device *dev,
const struct nvme_ctrl_ops *ops, unsigned long quirks);
void nvme_uninit_ctrl(struct nvme_ctrl *ctrl);
void nvme_put_ctrl(struct nvme_ctrl *ctrl);
int nvme_init_identify(struct nvme_ctrl *ctrl);
void nvme_queue_scan(struct nvme_ctrl *ctrl);
void nvme_remove_namespaces(struct nvme_ctrl *ctrl);
#define NVME_NR_AERS 1
void nvme_complete_async_event(struct nvme_ctrl *ctrl,
struct nvme_completion *cqe);
void nvme_queue_async_events(struct nvme_ctrl *ctrl);
void nvme_stop_queues(struct nvme_ctrl *ctrl);
void nvme_start_queues(struct nvme_ctrl *ctrl);
void nvme_kill_queues(struct nvme_ctrl *ctrl);
struct request *nvme_alloc_request(struct request_queue *q,
struct nvme_command *cmd, unsigned int flags);
void nvme_requeue_req(struct request *req);
int nvme_setup_cmd(struct nvme_ns *ns, struct request *req,
struct nvme_command *cmd);
int nvme_submit_sync_cmd(struct request_queue *q, struct nvme_command *cmd,
void *buf, unsigned bufflen);
int __nvme_submit_sync_cmd(struct request_queue *q, struct nvme_command *cmd,
struct nvme_completion *cqe, void *buffer, unsigned bufflen,
unsigned timeout);
int nvme_submit_user_cmd(struct request_queue *q, struct nvme_command *cmd,
void __user *ubuffer, unsigned bufflen, u32 *result,
unsigned timeout);
int __nvme_submit_user_cmd(struct request_queue *q, struct nvme_command *cmd,
void __user *ubuffer, unsigned bufflen,
void __user *meta_buffer, unsigned meta_len, u32 meta_seed,
u32 *result, unsigned timeout);
int nvme_identify_ctrl(struct nvme_ctrl *dev, struct nvme_id_ctrl **id);
int nvme_identify_ns(struct nvme_ctrl *dev, unsigned nsid,
struct nvme_id_ns **id);
int nvme_get_log_page(struct nvme_ctrl *dev, struct nvme_smart_log **log);
int nvme_get_features(struct nvme_ctrl *dev, unsigned fid, unsigned nsid,
dma_addr_t dma_addr, u32 *result);
int nvme_set_features(struct nvme_ctrl *dev, unsigned fid, unsigned dword11,
dma_addr_t dma_addr, u32 *result);
int nvme_set_queue_count(struct nvme_ctrl *ctrl, int *count);
struct sg_io_hdr;
int nvme_sg_io(struct nvme_ns *ns, struct sg_io_hdr __user *u_hdr);
int nvme_sg_io32(struct nvme_ns *ns, unsigned long arg);
int nvme_sg_get_version_num(int __user *ip);
#ifdef CONFIG_NVM
int nvme_nvm_ns_supported(struct nvme_ns *ns, struct nvme_id_ns *id);
int nvme_nvm_register(struct request_queue *q, char *disk_name);
void nvme_nvm_unregister(struct request_queue *q, char *disk_name);
#else
static inline int nvme_nvm_register(struct request_queue *q, char *disk_name)
{
return 0;
}
static inline void nvme_nvm_unregister(struct request_queue *q, char *disk_name) {};
static inline int nvme_nvm_ns_supported(struct nvme_ns *ns, struct nvme_id_ns *id)
{
return 0;
}
#endif /* CONFIG_NVM */
int __init nvme_core_init(void);
void nvme_core_exit(void);
#endif /* _NVME_H */