linux/drivers/block/nvme-core.c
Linus Torvalds b55b390202 Merge git://git.infradead.org/users/willy/linux-nvme
Pull NVMe update from Matthew Wilcox:
 "Mostly bugfixes again for the NVMe driver.  I'd like to call out the
  exported tracepoint in the block layer; I believe Keith has cleared
  this with Jens.

  We've had a few reports from people who're really pounding on NVMe
  devices at scale, hence the timeout changes (and new module
  parameters), hotplug cpu deadlock, tracepoints, and minor performance
  tweaks"

[ Jens hadn't seen that tracepoint thing, but is ok with it - it will
  end up going away when mq conversion happens ]

* git://git.infradead.org/users/willy/linux-nvme: (22 commits)
  NVMe: Fix START_STOP_UNIT Scsi->NVMe translation.
  NVMe: Use Log Page constants in SCSI emulation
  NVMe: Define Log Page constants
  NVMe: Fix hot cpu notification dead lock
  NVMe: Rename io_timeout to nvme_io_timeout
  NVMe: Use last bytes of f/w rev SCSI Inquiry
  NVMe: Adhere to request queue block accounting enable/disable
  NVMe: Fix nvme get/put queue semantics
  NVMe: Delete NVME_GET_FEAT_TEMP_THRESH
  NVMe: Make admin timeout a module parameter
  NVMe: Make iod bio timeout a parameter
  NVMe: Prevent possible NULL pointer dereference
  NVMe: Fix the buffer size passed in GetLogPage(CDW10.NUMD)
  NVMe: Update data structures for NVMe 1.2
  NVMe: Enable BUILD_BUG_ON checks
  NVMe: Update namespace and controller identify structures to the 1.1a spec
  NVMe: Flush with data support
  NVMe: Configure support for block flush
  NVMe: Add tracepoints
  NVMe: Protect against badly formatted CQEs
  ...
2014-06-15 15:58:03 -10:00

2978 lines
74 KiB
C

/*
* NVM Express device driver
* 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.
*/
#include <linux/nvme.h>
#include <linux/bio.h>
#include <linux/bitops.h>
#include <linux/blkdev.h>
#include <linux/cpu.h>
#include <linux/delay.h>
#include <linux/errno.h>
#include <linux/fs.h>
#include <linux/genhd.h>
#include <linux/hdreg.h>
#include <linux/idr.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/kdev_t.h>
#include <linux/kthread.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/pci.h>
#include <linux/percpu.h>
#include <linux/poison.h>
#include <linux/ptrace.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/types.h>
#include <scsi/sg.h>
#include <asm-generic/io-64-nonatomic-lo-hi.h>
#include <trace/events/block.h>
#define NVME_Q_DEPTH 1024
#define SQ_SIZE(depth) (depth * sizeof(struct nvme_command))
#define CQ_SIZE(depth) (depth * sizeof(struct nvme_completion))
#define ADMIN_TIMEOUT (admin_timeout * HZ)
#define IOD_TIMEOUT (retry_time * HZ)
static unsigned char admin_timeout = 60;
module_param(admin_timeout, byte, 0644);
MODULE_PARM_DESC(admin_timeout, "timeout in seconds for admin commands");
unsigned char nvme_io_timeout = 30;
module_param_named(io_timeout, nvme_io_timeout, byte, 0644);
MODULE_PARM_DESC(io_timeout, "timeout in seconds for I/O");
static unsigned char retry_time = 30;
module_param(retry_time, byte, 0644);
MODULE_PARM_DESC(retry_time, "time in seconds to retry failed I/O");
static int nvme_major;
module_param(nvme_major, int, 0);
static int use_threaded_interrupts;
module_param(use_threaded_interrupts, int, 0);
static DEFINE_SPINLOCK(dev_list_lock);
static LIST_HEAD(dev_list);
static struct task_struct *nvme_thread;
static struct workqueue_struct *nvme_workq;
static wait_queue_head_t nvme_kthread_wait;
static struct notifier_block nvme_nb;
static void nvme_reset_failed_dev(struct work_struct *ws);
struct async_cmd_info {
struct kthread_work work;
struct kthread_worker *worker;
u32 result;
int status;
void *ctx;
};
/*
* An NVM Express queue. Each device has at least two (one for admin
* commands and one for I/O commands).
*/
struct nvme_queue {
struct rcu_head r_head;
struct device *q_dmadev;
struct nvme_dev *dev;
char irqname[24]; /* nvme4294967295-65535\0 */
spinlock_t q_lock;
struct nvme_command *sq_cmds;
volatile struct nvme_completion *cqes;
dma_addr_t sq_dma_addr;
dma_addr_t cq_dma_addr;
wait_queue_head_t sq_full;
wait_queue_t sq_cong_wait;
struct bio_list sq_cong;
struct list_head iod_bio;
u32 __iomem *q_db;
u16 q_depth;
u16 cq_vector;
u16 sq_head;
u16 sq_tail;
u16 cq_head;
u16 qid;
u8 cq_phase;
u8 cqe_seen;
u8 q_suspended;
cpumask_var_t cpu_mask;
struct async_cmd_info cmdinfo;
unsigned long cmdid_data[];
};
/*
* Check we didin't inadvertently grow the command struct
*/
static inline void _nvme_check_size(void)
{
BUILD_BUG_ON(sizeof(struct nvme_rw_command) != 64);
BUILD_BUG_ON(sizeof(struct nvme_create_cq) != 64);
BUILD_BUG_ON(sizeof(struct nvme_create_sq) != 64);
BUILD_BUG_ON(sizeof(struct nvme_delete_queue) != 64);
BUILD_BUG_ON(sizeof(struct nvme_features) != 64);
BUILD_BUG_ON(sizeof(struct nvme_format_cmd) != 64);
BUILD_BUG_ON(sizeof(struct nvme_abort_cmd) != 64);
BUILD_BUG_ON(sizeof(struct nvme_command) != 64);
BUILD_BUG_ON(sizeof(struct nvme_id_ctrl) != 4096);
BUILD_BUG_ON(sizeof(struct nvme_id_ns) != 4096);
BUILD_BUG_ON(sizeof(struct nvme_lba_range_type) != 64);
BUILD_BUG_ON(sizeof(struct nvme_smart_log) != 512);
}
typedef void (*nvme_completion_fn)(struct nvme_queue *, void *,
struct nvme_completion *);
struct nvme_cmd_info {
nvme_completion_fn fn;
void *ctx;
unsigned long timeout;
int aborted;
};
static struct nvme_cmd_info *nvme_cmd_info(struct nvme_queue *nvmeq)
{
return (void *)&nvmeq->cmdid_data[BITS_TO_LONGS(nvmeq->q_depth)];
}
static unsigned nvme_queue_extra(int depth)
{
return DIV_ROUND_UP(depth, 8) + (depth * sizeof(struct nvme_cmd_info));
}
/**
* alloc_cmdid() - Allocate a Command ID
* @nvmeq: The queue that will be used for this command
* @ctx: A pointer that will be passed to the handler
* @handler: The function to call on completion
*
* Allocate a Command ID for a queue. The data passed in will
* be passed to the completion handler. This is implemented by using
* the bottom two bits of the ctx pointer to store the handler ID.
* Passing in a pointer that's not 4-byte aligned will cause a BUG.
* We can change this if it becomes a problem.
*
* May be called with local interrupts disabled and the q_lock held,
* or with interrupts enabled and no locks held.
*/
static int alloc_cmdid(struct nvme_queue *nvmeq, void *ctx,
nvme_completion_fn handler, unsigned timeout)
{
int depth = nvmeq->q_depth - 1;
struct nvme_cmd_info *info = nvme_cmd_info(nvmeq);
int cmdid;
do {
cmdid = find_first_zero_bit(nvmeq->cmdid_data, depth);
if (cmdid >= depth)
return -EBUSY;
} while (test_and_set_bit(cmdid, nvmeq->cmdid_data));
info[cmdid].fn = handler;
info[cmdid].ctx = ctx;
info[cmdid].timeout = jiffies + timeout;
info[cmdid].aborted = 0;
return cmdid;
}
static int alloc_cmdid_killable(struct nvme_queue *nvmeq, void *ctx,
nvme_completion_fn handler, unsigned timeout)
{
int cmdid;
wait_event_killable(nvmeq->sq_full,
(cmdid = alloc_cmdid(nvmeq, ctx, handler, timeout)) >= 0);
return (cmdid < 0) ? -EINTR : cmdid;
}
/* Special values must be less than 0x1000 */
#define CMD_CTX_BASE ((void *)POISON_POINTER_DELTA)
#define CMD_CTX_CANCELLED (0x30C + CMD_CTX_BASE)
#define CMD_CTX_COMPLETED (0x310 + CMD_CTX_BASE)
#define CMD_CTX_INVALID (0x314 + CMD_CTX_BASE)
#define CMD_CTX_ABORT (0x318 + CMD_CTX_BASE)
static void special_completion(struct nvme_queue *nvmeq, void *ctx,
struct nvme_completion *cqe)
{
if (ctx == CMD_CTX_CANCELLED)
return;
if (ctx == CMD_CTX_ABORT) {
++nvmeq->dev->abort_limit;
return;
}
if (ctx == CMD_CTX_COMPLETED) {
dev_warn(nvmeq->q_dmadev,
"completed id %d twice on queue %d\n",
cqe->command_id, le16_to_cpup(&cqe->sq_id));
return;
}
if (ctx == CMD_CTX_INVALID) {
dev_warn(nvmeq->q_dmadev,
"invalid id %d completed on queue %d\n",
cqe->command_id, le16_to_cpup(&cqe->sq_id));
return;
}
dev_warn(nvmeq->q_dmadev, "Unknown special completion %p\n", ctx);
}
static void async_completion(struct nvme_queue *nvmeq, void *ctx,
struct nvme_completion *cqe)
{
struct async_cmd_info *cmdinfo = ctx;
cmdinfo->result = le32_to_cpup(&cqe->result);
cmdinfo->status = le16_to_cpup(&cqe->status) >> 1;
queue_kthread_work(cmdinfo->worker, &cmdinfo->work);
}
/*
* Called with local interrupts disabled and the q_lock held. May not sleep.
*/
static void *free_cmdid(struct nvme_queue *nvmeq, int cmdid,
nvme_completion_fn *fn)
{
void *ctx;
struct nvme_cmd_info *info = nvme_cmd_info(nvmeq);
if (cmdid >= nvmeq->q_depth || !info[cmdid].fn) {
if (fn)
*fn = special_completion;
return CMD_CTX_INVALID;
}
if (fn)
*fn = info[cmdid].fn;
ctx = info[cmdid].ctx;
info[cmdid].fn = special_completion;
info[cmdid].ctx = CMD_CTX_COMPLETED;
clear_bit(cmdid, nvmeq->cmdid_data);
wake_up(&nvmeq->sq_full);
return ctx;
}
static void *cancel_cmdid(struct nvme_queue *nvmeq, int cmdid,
nvme_completion_fn *fn)
{
void *ctx;
struct nvme_cmd_info *info = nvme_cmd_info(nvmeq);
if (fn)
*fn = info[cmdid].fn;
ctx = info[cmdid].ctx;
info[cmdid].fn = special_completion;
info[cmdid].ctx = CMD_CTX_CANCELLED;
return ctx;
}
static struct nvme_queue *raw_nvmeq(struct nvme_dev *dev, int qid)
{
return rcu_dereference_raw(dev->queues[qid]);
}
static struct nvme_queue *get_nvmeq(struct nvme_dev *dev) __acquires(RCU)
{
struct nvme_queue *nvmeq;
unsigned queue_id = get_cpu_var(*dev->io_queue);
rcu_read_lock();
nvmeq = rcu_dereference(dev->queues[queue_id]);
if (nvmeq)
return nvmeq;
rcu_read_unlock();
put_cpu_var(*dev->io_queue);
return NULL;
}
static void put_nvmeq(struct nvme_queue *nvmeq) __releases(RCU)
{
rcu_read_unlock();
put_cpu_var(nvmeq->dev->io_queue);
}
static struct nvme_queue *lock_nvmeq(struct nvme_dev *dev, int q_idx)
__acquires(RCU)
{
struct nvme_queue *nvmeq;
rcu_read_lock();
nvmeq = rcu_dereference(dev->queues[q_idx]);
if (nvmeq)
return nvmeq;
rcu_read_unlock();
return NULL;
}
static void unlock_nvmeq(struct nvme_queue *nvmeq) __releases(RCU)
{
rcu_read_unlock();
}
/**
* nvme_submit_cmd() - Copy a command into a queue and ring the doorbell
* @nvmeq: The queue to use
* @cmd: The command to send
*
* Safe to use from interrupt context
*/
static int nvme_submit_cmd(struct nvme_queue *nvmeq, struct nvme_command *cmd)
{
unsigned long flags;
u16 tail;
spin_lock_irqsave(&nvmeq->q_lock, flags);
if (nvmeq->q_suspended) {
spin_unlock_irqrestore(&nvmeq->q_lock, flags);
return -EBUSY;
}
tail = nvmeq->sq_tail;
memcpy(&nvmeq->sq_cmds[tail], cmd, sizeof(*cmd));
if (++tail == nvmeq->q_depth)
tail = 0;
writel(tail, nvmeq->q_db);
nvmeq->sq_tail = tail;
spin_unlock_irqrestore(&nvmeq->q_lock, flags);
return 0;
}
static __le64 **iod_list(struct nvme_iod *iod)
{
return ((void *)iod) + iod->offset;
}
/*
* Will slightly overestimate the number of pages needed. This is OK
* as it only leads to a small amount of wasted memory for the lifetime of
* the I/O.
*/
static int nvme_npages(unsigned size)
{
unsigned nprps = DIV_ROUND_UP(size + PAGE_SIZE, PAGE_SIZE);
return DIV_ROUND_UP(8 * nprps, PAGE_SIZE - 8);
}
static struct nvme_iod *
nvme_alloc_iod(unsigned nseg, unsigned nbytes, gfp_t gfp)
{
struct nvme_iod *iod = kmalloc(sizeof(struct nvme_iod) +
sizeof(__le64 *) * nvme_npages(nbytes) +
sizeof(struct scatterlist) * nseg, gfp);
if (iod) {
iod->offset = offsetof(struct nvme_iod, sg[nseg]);
iod->npages = -1;
iod->length = nbytes;
iod->nents = 0;
iod->first_dma = 0ULL;
iod->start_time = jiffies;
}
return iod;
}
void nvme_free_iod(struct nvme_dev *dev, struct nvme_iod *iod)
{
const int last_prp = PAGE_SIZE / 8 - 1;
int i;
__le64 **list = iod_list(iod);
dma_addr_t prp_dma = iod->first_dma;
if (iod->npages == 0)
dma_pool_free(dev->prp_small_pool, list[0], prp_dma);
for (i = 0; i < iod->npages; i++) {
__le64 *prp_list = list[i];
dma_addr_t next_prp_dma = le64_to_cpu(prp_list[last_prp]);
dma_pool_free(dev->prp_page_pool, prp_list, prp_dma);
prp_dma = next_prp_dma;
}
kfree(iod);
}
static void nvme_start_io_acct(struct bio *bio)
{
struct gendisk *disk = bio->bi_bdev->bd_disk;
if (blk_queue_io_stat(disk->queue)) {
const int rw = bio_data_dir(bio);
int cpu = part_stat_lock();
part_round_stats(cpu, &disk->part0);
part_stat_inc(cpu, &disk->part0, ios[rw]);
part_stat_add(cpu, &disk->part0, sectors[rw],
bio_sectors(bio));
part_inc_in_flight(&disk->part0, rw);
part_stat_unlock();
}
}
static void nvme_end_io_acct(struct bio *bio, unsigned long start_time)
{
struct gendisk *disk = bio->bi_bdev->bd_disk;
if (blk_queue_io_stat(disk->queue)) {
const int rw = bio_data_dir(bio);
unsigned long duration = jiffies - start_time;
int cpu = part_stat_lock();
part_stat_add(cpu, &disk->part0, ticks[rw], duration);
part_round_stats(cpu, &disk->part0);
part_dec_in_flight(&disk->part0, rw);
part_stat_unlock();
}
}
static void bio_completion(struct nvme_queue *nvmeq, void *ctx,
struct nvme_completion *cqe)
{
struct nvme_iod *iod = ctx;
struct bio *bio = iod->private;
u16 status = le16_to_cpup(&cqe->status) >> 1;
int error = 0;
if (unlikely(status)) {
if (!(status & NVME_SC_DNR ||
bio->bi_rw & REQ_FAILFAST_MASK) &&
(jiffies - iod->start_time) < IOD_TIMEOUT) {
if (!waitqueue_active(&nvmeq->sq_full))
add_wait_queue(&nvmeq->sq_full,
&nvmeq->sq_cong_wait);
list_add_tail(&iod->node, &nvmeq->iod_bio);
wake_up(&nvmeq->sq_full);
return;
}
error = -EIO;
}
if (iod->nents) {
dma_unmap_sg(nvmeq->q_dmadev, iod->sg, iod->nents,
bio_data_dir(bio) ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
nvme_end_io_acct(bio, iod->start_time);
}
nvme_free_iod(nvmeq->dev, iod);
trace_block_bio_complete(bdev_get_queue(bio->bi_bdev), bio, error);
bio_endio(bio, error);
}
/* length is in bytes. gfp flags indicates whether we may sleep. */
int nvme_setup_prps(struct nvme_dev *dev, struct nvme_iod *iod, int total_len,
gfp_t gfp)
{
struct dma_pool *pool;
int length = total_len;
struct scatterlist *sg = iod->sg;
int dma_len = sg_dma_len(sg);
u64 dma_addr = sg_dma_address(sg);
int offset = offset_in_page(dma_addr);
__le64 *prp_list;
__le64 **list = iod_list(iod);
dma_addr_t prp_dma;
int nprps, i;
length -= (PAGE_SIZE - offset);
if (length <= 0)
return total_len;
dma_len -= (PAGE_SIZE - offset);
if (dma_len) {
dma_addr += (PAGE_SIZE - offset);
} else {
sg = sg_next(sg);
dma_addr = sg_dma_address(sg);
dma_len = sg_dma_len(sg);
}
if (length <= PAGE_SIZE) {
iod->first_dma = dma_addr;
return total_len;
}
nprps = DIV_ROUND_UP(length, PAGE_SIZE);
if (nprps <= (256 / 8)) {
pool = dev->prp_small_pool;
iod->npages = 0;
} else {
pool = dev->prp_page_pool;
iod->npages = 1;
}
prp_list = dma_pool_alloc(pool, gfp, &prp_dma);
if (!prp_list) {
iod->first_dma = dma_addr;
iod->npages = -1;
return (total_len - length) + PAGE_SIZE;
}
list[0] = prp_list;
iod->first_dma = prp_dma;
i = 0;
for (;;) {
if (i == PAGE_SIZE / 8) {
__le64 *old_prp_list = prp_list;
prp_list = dma_pool_alloc(pool, gfp, &prp_dma);
if (!prp_list)
return total_len - length;
list[iod->npages++] = prp_list;
prp_list[0] = old_prp_list[i - 1];
old_prp_list[i - 1] = cpu_to_le64(prp_dma);
i = 1;
}
prp_list[i++] = cpu_to_le64(dma_addr);
dma_len -= PAGE_SIZE;
dma_addr += PAGE_SIZE;
length -= PAGE_SIZE;
if (length <= 0)
break;
if (dma_len > 0)
continue;
BUG_ON(dma_len < 0);
sg = sg_next(sg);
dma_addr = sg_dma_address(sg);
dma_len = sg_dma_len(sg);
}
return total_len;
}
static int nvme_split_and_submit(struct bio *bio, struct nvme_queue *nvmeq,
int len)
{
struct bio *split = bio_split(bio, len >> 9, GFP_ATOMIC, NULL);
if (!split)
return -ENOMEM;
trace_block_split(bdev_get_queue(bio->bi_bdev), bio,
split->bi_iter.bi_sector);
bio_chain(split, bio);
if (!waitqueue_active(&nvmeq->sq_full))
add_wait_queue(&nvmeq->sq_full, &nvmeq->sq_cong_wait);
bio_list_add(&nvmeq->sq_cong, split);
bio_list_add(&nvmeq->sq_cong, bio);
wake_up(&nvmeq->sq_full);
return 0;
}
/* NVMe scatterlists require no holes in the virtual address */
#define BIOVEC_NOT_VIRT_MERGEABLE(vec1, vec2) ((vec2)->bv_offset || \
(((vec1)->bv_offset + (vec1)->bv_len) % PAGE_SIZE))
static int nvme_map_bio(struct nvme_queue *nvmeq, struct nvme_iod *iod,
struct bio *bio, enum dma_data_direction dma_dir, int psegs)
{
struct bio_vec bvec, bvprv;
struct bvec_iter iter;
struct scatterlist *sg = NULL;
int length = 0, nsegs = 0, split_len = bio->bi_iter.bi_size;
int first = 1;
if (nvmeq->dev->stripe_size)
split_len = nvmeq->dev->stripe_size -
((bio->bi_iter.bi_sector << 9) &
(nvmeq->dev->stripe_size - 1));
sg_init_table(iod->sg, psegs);
bio_for_each_segment(bvec, bio, iter) {
if (!first && BIOVEC_PHYS_MERGEABLE(&bvprv, &bvec)) {
sg->length += bvec.bv_len;
} else {
if (!first && BIOVEC_NOT_VIRT_MERGEABLE(&bvprv, &bvec))
return nvme_split_and_submit(bio, nvmeq,
length);
sg = sg ? sg + 1 : iod->sg;
sg_set_page(sg, bvec.bv_page,
bvec.bv_len, bvec.bv_offset);
nsegs++;
}
if (split_len - length < bvec.bv_len)
return nvme_split_and_submit(bio, nvmeq, split_len);
length += bvec.bv_len;
bvprv = bvec;
first = 0;
}
iod->nents = nsegs;
sg_mark_end(sg);
if (dma_map_sg(nvmeq->q_dmadev, iod->sg, iod->nents, dma_dir) == 0)
return -ENOMEM;
BUG_ON(length != bio->bi_iter.bi_size);
return length;
}
static int nvme_submit_discard(struct nvme_queue *nvmeq, struct nvme_ns *ns,
struct bio *bio, struct nvme_iod *iod, int cmdid)
{
struct nvme_dsm_range *range =
(struct nvme_dsm_range *)iod_list(iod)[0];
struct nvme_command *cmnd = &nvmeq->sq_cmds[nvmeq->sq_tail];
range->cattr = cpu_to_le32(0);
range->nlb = cpu_to_le32(bio->bi_iter.bi_size >> ns->lba_shift);
range->slba = cpu_to_le64(nvme_block_nr(ns, bio->bi_iter.bi_sector));
memset(cmnd, 0, sizeof(*cmnd));
cmnd->dsm.opcode = nvme_cmd_dsm;
cmnd->dsm.command_id = cmdid;
cmnd->dsm.nsid = cpu_to_le32(ns->ns_id);
cmnd->dsm.prp1 = cpu_to_le64(iod->first_dma);
cmnd->dsm.nr = 0;
cmnd->dsm.attributes = cpu_to_le32(NVME_DSMGMT_AD);
if (++nvmeq->sq_tail == nvmeq->q_depth)
nvmeq->sq_tail = 0;
writel(nvmeq->sq_tail, nvmeq->q_db);
return 0;
}
static int nvme_submit_flush(struct nvme_queue *nvmeq, struct nvme_ns *ns,
int cmdid)
{
struct nvme_command *cmnd = &nvmeq->sq_cmds[nvmeq->sq_tail];
memset(cmnd, 0, sizeof(*cmnd));
cmnd->common.opcode = nvme_cmd_flush;
cmnd->common.command_id = cmdid;
cmnd->common.nsid = cpu_to_le32(ns->ns_id);
if (++nvmeq->sq_tail == nvmeq->q_depth)
nvmeq->sq_tail = 0;
writel(nvmeq->sq_tail, nvmeq->q_db);
return 0;
}
static int nvme_submit_iod(struct nvme_queue *nvmeq, struct nvme_iod *iod)
{
struct bio *bio = iod->private;
struct nvme_ns *ns = bio->bi_bdev->bd_disk->private_data;
struct nvme_command *cmnd;
int cmdid;
u16 control;
u32 dsmgmt;
cmdid = alloc_cmdid(nvmeq, iod, bio_completion, NVME_IO_TIMEOUT);
if (unlikely(cmdid < 0))
return cmdid;
if (bio->bi_rw & REQ_DISCARD)
return nvme_submit_discard(nvmeq, ns, bio, iod, cmdid);
if (bio->bi_rw & REQ_FLUSH)
return nvme_submit_flush(nvmeq, ns, cmdid);
control = 0;
if (bio->bi_rw & REQ_FUA)
control |= NVME_RW_FUA;
if (bio->bi_rw & (REQ_FAILFAST_DEV | REQ_RAHEAD))
control |= NVME_RW_LR;
dsmgmt = 0;
if (bio->bi_rw & REQ_RAHEAD)
dsmgmt |= NVME_RW_DSM_FREQ_PREFETCH;
cmnd = &nvmeq->sq_cmds[nvmeq->sq_tail];
memset(cmnd, 0, sizeof(*cmnd));
cmnd->rw.opcode = bio_data_dir(bio) ? nvme_cmd_write : nvme_cmd_read;
cmnd->rw.command_id = cmdid;
cmnd->rw.nsid = cpu_to_le32(ns->ns_id);
cmnd->rw.prp1 = cpu_to_le64(sg_dma_address(iod->sg));
cmnd->rw.prp2 = cpu_to_le64(iod->first_dma);
cmnd->rw.slba = cpu_to_le64(nvme_block_nr(ns, bio->bi_iter.bi_sector));
cmnd->rw.length =
cpu_to_le16((bio->bi_iter.bi_size >> ns->lba_shift) - 1);
cmnd->rw.control = cpu_to_le16(control);
cmnd->rw.dsmgmt = cpu_to_le32(dsmgmt);
if (++nvmeq->sq_tail == nvmeq->q_depth)
nvmeq->sq_tail = 0;
writel(nvmeq->sq_tail, nvmeq->q_db);
return 0;
}
static int nvme_split_flush_data(struct nvme_queue *nvmeq, struct bio *bio)
{
struct bio *split = bio_clone(bio, GFP_ATOMIC);
if (!split)
return -ENOMEM;
split->bi_iter.bi_size = 0;
split->bi_phys_segments = 0;
bio->bi_rw &= ~REQ_FLUSH;
bio_chain(split, bio);
if (!waitqueue_active(&nvmeq->sq_full))
add_wait_queue(&nvmeq->sq_full, &nvmeq->sq_cong_wait);
bio_list_add(&nvmeq->sq_cong, split);
bio_list_add(&nvmeq->sq_cong, bio);
wake_up_process(nvme_thread);
return 0;
}
/*
* Called with local interrupts disabled and the q_lock held. May not sleep.
*/
static int nvme_submit_bio_queue(struct nvme_queue *nvmeq, struct nvme_ns *ns,
struct bio *bio)
{
struct nvme_iod *iod;
int psegs = bio_phys_segments(ns->queue, bio);
int result;
if ((bio->bi_rw & REQ_FLUSH) && psegs)
return nvme_split_flush_data(nvmeq, bio);
iod = nvme_alloc_iod(psegs, bio->bi_iter.bi_size, GFP_ATOMIC);
if (!iod)
return -ENOMEM;
iod->private = bio;
if (bio->bi_rw & REQ_DISCARD) {
void *range;
/*
* We reuse the small pool to allocate the 16-byte range here
* as it is not worth having a special pool for these or
* additional cases to handle freeing the iod.
*/
range = dma_pool_alloc(nvmeq->dev->prp_small_pool,
GFP_ATOMIC,
&iod->first_dma);
if (!range) {
result = -ENOMEM;
goto free_iod;
}
iod_list(iod)[0] = (__le64 *)range;
iod->npages = 0;
} else if (psegs) {
result = nvme_map_bio(nvmeq, iod, bio,
bio_data_dir(bio) ? DMA_TO_DEVICE : DMA_FROM_DEVICE,
psegs);
if (result <= 0)
goto free_iod;
if (nvme_setup_prps(nvmeq->dev, iod, result, GFP_ATOMIC) !=
result) {
result = -ENOMEM;
goto free_iod;
}
nvme_start_io_acct(bio);
}
if (unlikely(nvme_submit_iod(nvmeq, iod))) {
if (!waitqueue_active(&nvmeq->sq_full))
add_wait_queue(&nvmeq->sq_full, &nvmeq->sq_cong_wait);
list_add_tail(&iod->node, &nvmeq->iod_bio);
}
return 0;
free_iod:
nvme_free_iod(nvmeq->dev, iod);
return result;
}
static int nvme_process_cq(struct nvme_queue *nvmeq)
{
u16 head, phase;
head = nvmeq->cq_head;
phase = nvmeq->cq_phase;
for (;;) {
void *ctx;
nvme_completion_fn fn;
struct nvme_completion cqe = nvmeq->cqes[head];
if ((le16_to_cpu(cqe.status) & 1) != phase)
break;
nvmeq->sq_head = le16_to_cpu(cqe.sq_head);
if (++head == nvmeq->q_depth) {
head = 0;
phase = !phase;
}
ctx = free_cmdid(nvmeq, cqe.command_id, &fn);
fn(nvmeq, ctx, &cqe);
}
/* If the controller ignores the cq head doorbell and continuously
* writes to the queue, it is theoretically possible to wrap around
* the queue twice and mistakenly return IRQ_NONE. Linux only
* requires that 0.1% of your interrupts are handled, so this isn't
* a big problem.
*/
if (head == nvmeq->cq_head && phase == nvmeq->cq_phase)
return 0;
writel(head, nvmeq->q_db + nvmeq->dev->db_stride);
nvmeq->cq_head = head;
nvmeq->cq_phase = phase;
nvmeq->cqe_seen = 1;
return 1;
}
static void nvme_make_request(struct request_queue *q, struct bio *bio)
{
struct nvme_ns *ns = q->queuedata;
struct nvme_queue *nvmeq = get_nvmeq(ns->dev);
int result = -EBUSY;
if (!nvmeq) {
bio_endio(bio, -EIO);
return;
}
spin_lock_irq(&nvmeq->q_lock);
if (!nvmeq->q_suspended && bio_list_empty(&nvmeq->sq_cong))
result = nvme_submit_bio_queue(nvmeq, ns, bio);
if (unlikely(result)) {
if (!waitqueue_active(&nvmeq->sq_full))
add_wait_queue(&nvmeq->sq_full, &nvmeq->sq_cong_wait);
bio_list_add(&nvmeq->sq_cong, bio);
}
nvme_process_cq(nvmeq);
spin_unlock_irq(&nvmeq->q_lock);
put_nvmeq(nvmeq);
}
static irqreturn_t nvme_irq(int irq, void *data)
{
irqreturn_t result;
struct nvme_queue *nvmeq = data;
spin_lock(&nvmeq->q_lock);
nvme_process_cq(nvmeq);
result = nvmeq->cqe_seen ? IRQ_HANDLED : IRQ_NONE;
nvmeq->cqe_seen = 0;
spin_unlock(&nvmeq->q_lock);
return result;
}
static irqreturn_t nvme_irq_check(int irq, void *data)
{
struct nvme_queue *nvmeq = data;
struct nvme_completion cqe = nvmeq->cqes[nvmeq->cq_head];
if ((le16_to_cpu(cqe.status) & 1) != nvmeq->cq_phase)
return IRQ_NONE;
return IRQ_WAKE_THREAD;
}
static void nvme_abort_command(struct nvme_queue *nvmeq, int cmdid)
{
spin_lock_irq(&nvmeq->q_lock);
cancel_cmdid(nvmeq, cmdid, NULL);
spin_unlock_irq(&nvmeq->q_lock);
}
struct sync_cmd_info {
struct task_struct *task;
u32 result;
int status;
};
static void sync_completion(struct nvme_queue *nvmeq, void *ctx,
struct nvme_completion *cqe)
{
struct sync_cmd_info *cmdinfo = ctx;
cmdinfo->result = le32_to_cpup(&cqe->result);
cmdinfo->status = le16_to_cpup(&cqe->status) >> 1;
wake_up_process(cmdinfo->task);
}
/*
* Returns 0 on success. If the result is negative, it's a Linux error code;
* if the result is positive, it's an NVM Express status code
*/
static int nvme_submit_sync_cmd(struct nvme_dev *dev, int q_idx,
struct nvme_command *cmd,
u32 *result, unsigned timeout)
{
int cmdid, ret;
struct sync_cmd_info cmdinfo;
struct nvme_queue *nvmeq;
nvmeq = lock_nvmeq(dev, q_idx);
if (!nvmeq)
return -ENODEV;
cmdinfo.task = current;
cmdinfo.status = -EINTR;
cmdid = alloc_cmdid(nvmeq, &cmdinfo, sync_completion, timeout);
if (cmdid < 0) {
unlock_nvmeq(nvmeq);
return cmdid;
}
cmd->common.command_id = cmdid;
set_current_state(TASK_KILLABLE);
ret = nvme_submit_cmd(nvmeq, cmd);
if (ret) {
free_cmdid(nvmeq, cmdid, NULL);
unlock_nvmeq(nvmeq);
set_current_state(TASK_RUNNING);
return ret;
}
unlock_nvmeq(nvmeq);
schedule_timeout(timeout);
if (cmdinfo.status == -EINTR) {
nvmeq = lock_nvmeq(dev, q_idx);
if (nvmeq) {
nvme_abort_command(nvmeq, cmdid);
unlock_nvmeq(nvmeq);
}
return -EINTR;
}
if (result)
*result = cmdinfo.result;
return cmdinfo.status;
}
static int nvme_submit_async_cmd(struct nvme_queue *nvmeq,
struct nvme_command *cmd,
struct async_cmd_info *cmdinfo, unsigned timeout)
{
int cmdid;
cmdid = alloc_cmdid_killable(nvmeq, cmdinfo, async_completion, timeout);
if (cmdid < 0)
return cmdid;
cmdinfo->status = -EINTR;
cmd->common.command_id = cmdid;
return nvme_submit_cmd(nvmeq, cmd);
}
int nvme_submit_admin_cmd(struct nvme_dev *dev, struct nvme_command *cmd,
u32 *result)
{
return nvme_submit_sync_cmd(dev, 0, cmd, result, ADMIN_TIMEOUT);
}
int nvme_submit_io_cmd(struct nvme_dev *dev, struct nvme_command *cmd,
u32 *result)
{
return nvme_submit_sync_cmd(dev, smp_processor_id() + 1, cmd, result,
NVME_IO_TIMEOUT);
}
static int nvme_submit_admin_cmd_async(struct nvme_dev *dev,
struct nvme_command *cmd, struct async_cmd_info *cmdinfo)
{
return nvme_submit_async_cmd(raw_nvmeq(dev, 0), cmd, cmdinfo,
ADMIN_TIMEOUT);
}
static int adapter_delete_queue(struct nvme_dev *dev, u8 opcode, u16 id)
{
int status;
struct nvme_command c;
memset(&c, 0, sizeof(c));
c.delete_queue.opcode = opcode;
c.delete_queue.qid = cpu_to_le16(id);
status = nvme_submit_admin_cmd(dev, &c, NULL);
if (status)
return -EIO;
return 0;
}
static int adapter_alloc_cq(struct nvme_dev *dev, u16 qid,
struct nvme_queue *nvmeq)
{
int status;
struct nvme_command c;
int flags = NVME_QUEUE_PHYS_CONTIG | NVME_CQ_IRQ_ENABLED;
memset(&c, 0, sizeof(c));
c.create_cq.opcode = nvme_admin_create_cq;
c.create_cq.prp1 = cpu_to_le64(nvmeq->cq_dma_addr);
c.create_cq.cqid = cpu_to_le16(qid);
c.create_cq.qsize = cpu_to_le16(nvmeq->q_depth - 1);
c.create_cq.cq_flags = cpu_to_le16(flags);
c.create_cq.irq_vector = cpu_to_le16(nvmeq->cq_vector);
status = nvme_submit_admin_cmd(dev, &c, NULL);
if (status)
return -EIO;
return 0;
}
static int adapter_alloc_sq(struct nvme_dev *dev, u16 qid,
struct nvme_queue *nvmeq)
{
int status;
struct nvme_command c;
int flags = NVME_QUEUE_PHYS_CONTIG | NVME_SQ_PRIO_MEDIUM;
memset(&c, 0, sizeof(c));
c.create_sq.opcode = nvme_admin_create_sq;
c.create_sq.prp1 = cpu_to_le64(nvmeq->sq_dma_addr);
c.create_sq.sqid = cpu_to_le16(qid);
c.create_sq.qsize = cpu_to_le16(nvmeq->q_depth - 1);
c.create_sq.sq_flags = cpu_to_le16(flags);
c.create_sq.cqid = cpu_to_le16(qid);
status = nvme_submit_admin_cmd(dev, &c, NULL);
if (status)
return -EIO;
return 0;
}
static int adapter_delete_cq(struct nvme_dev *dev, u16 cqid)
{
return adapter_delete_queue(dev, nvme_admin_delete_cq, cqid);
}
static int adapter_delete_sq(struct nvme_dev *dev, u16 sqid)
{
return adapter_delete_queue(dev, nvme_admin_delete_sq, sqid);
}
int nvme_identify(struct nvme_dev *dev, unsigned nsid, unsigned cns,
dma_addr_t dma_addr)
{
struct nvme_command c;
memset(&c, 0, sizeof(c));
c.identify.opcode = nvme_admin_identify;
c.identify.nsid = cpu_to_le32(nsid);
c.identify.prp1 = cpu_to_le64(dma_addr);
c.identify.cns = cpu_to_le32(cns);
return nvme_submit_admin_cmd(dev, &c, NULL);
}
int nvme_get_features(struct nvme_dev *dev, unsigned fid, unsigned nsid,
dma_addr_t dma_addr, u32 *result)
{
struct nvme_command c;
memset(&c, 0, sizeof(c));
c.features.opcode = nvme_admin_get_features;
c.features.nsid = cpu_to_le32(nsid);
c.features.prp1 = cpu_to_le64(dma_addr);
c.features.fid = cpu_to_le32(fid);
return nvme_submit_admin_cmd(dev, &c, result);
}
int nvme_set_features(struct nvme_dev *dev, unsigned fid, unsigned dword11,
dma_addr_t dma_addr, u32 *result)
{
struct nvme_command c;
memset(&c, 0, sizeof(c));
c.features.opcode = nvme_admin_set_features;
c.features.prp1 = cpu_to_le64(dma_addr);
c.features.fid = cpu_to_le32(fid);
c.features.dword11 = cpu_to_le32(dword11);
return nvme_submit_admin_cmd(dev, &c, result);
}
/**
* nvme_abort_cmd - Attempt aborting a command
* @cmdid: Command id of a timed out IO
* @queue: The queue with timed out IO
*
* Schedule controller reset if the command was already aborted once before and
* still hasn't been returned to the driver, or if this is the admin queue.
*/
static void nvme_abort_cmd(int cmdid, struct nvme_queue *nvmeq)
{
int a_cmdid;
struct nvme_command cmd;
struct nvme_dev *dev = nvmeq->dev;
struct nvme_cmd_info *info = nvme_cmd_info(nvmeq);
struct nvme_queue *adminq;
if (!nvmeq->qid || info[cmdid].aborted) {
if (work_busy(&dev->reset_work))
return;
list_del_init(&dev->node);
dev_warn(&dev->pci_dev->dev,
"I/O %d QID %d timeout, reset controller\n", cmdid,
nvmeq->qid);
dev->reset_workfn = nvme_reset_failed_dev;
queue_work(nvme_workq, &dev->reset_work);
return;
}
if (!dev->abort_limit)
return;
adminq = rcu_dereference(dev->queues[0]);
a_cmdid = alloc_cmdid(adminq, CMD_CTX_ABORT, special_completion,
ADMIN_TIMEOUT);
if (a_cmdid < 0)
return;
memset(&cmd, 0, sizeof(cmd));
cmd.abort.opcode = nvme_admin_abort_cmd;
cmd.abort.cid = cmdid;
cmd.abort.sqid = cpu_to_le16(nvmeq->qid);
cmd.abort.command_id = a_cmdid;
--dev->abort_limit;
info[cmdid].aborted = 1;
info[cmdid].timeout = jiffies + ADMIN_TIMEOUT;
dev_warn(nvmeq->q_dmadev, "Aborting I/O %d QID %d\n", cmdid,
nvmeq->qid);
nvme_submit_cmd(adminq, &cmd);
}
/**
* nvme_cancel_ios - Cancel outstanding I/Os
* @queue: The queue to cancel I/Os on
* @timeout: True to only cancel I/Os which have timed out
*/
static void nvme_cancel_ios(struct nvme_queue *nvmeq, bool timeout)
{
int depth = nvmeq->q_depth - 1;
struct nvme_cmd_info *info = nvme_cmd_info(nvmeq);
unsigned long now = jiffies;
int cmdid;
for_each_set_bit(cmdid, nvmeq->cmdid_data, depth) {
void *ctx;
nvme_completion_fn fn;
static struct nvme_completion cqe = {
.status = cpu_to_le16(NVME_SC_ABORT_REQ << 1),
};
if (timeout && !time_after(now, info[cmdid].timeout))
continue;
if (info[cmdid].ctx == CMD_CTX_CANCELLED)
continue;
if (timeout && nvmeq->dev->initialized) {
nvme_abort_cmd(cmdid, nvmeq);
continue;
}
dev_warn(nvmeq->q_dmadev, "Cancelling I/O %d QID %d\n", cmdid,
nvmeq->qid);
ctx = cancel_cmdid(nvmeq, cmdid, &fn);
fn(nvmeq, ctx, &cqe);
}
}
static void nvme_free_queue(struct rcu_head *r)
{
struct nvme_queue *nvmeq = container_of(r, struct nvme_queue, r_head);
spin_lock_irq(&nvmeq->q_lock);
while (bio_list_peek(&nvmeq->sq_cong)) {
struct bio *bio = bio_list_pop(&nvmeq->sq_cong);
bio_endio(bio, -EIO);
}
while (!list_empty(&nvmeq->iod_bio)) {
static struct nvme_completion cqe = {
.status = cpu_to_le16(
(NVME_SC_ABORT_REQ | NVME_SC_DNR) << 1),
};
struct nvme_iod *iod = list_first_entry(&nvmeq->iod_bio,
struct nvme_iod,
node);
list_del(&iod->node);
bio_completion(nvmeq, iod, &cqe);
}
spin_unlock_irq(&nvmeq->q_lock);
dma_free_coherent(nvmeq->q_dmadev, CQ_SIZE(nvmeq->q_depth),
(void *)nvmeq->cqes, nvmeq->cq_dma_addr);
dma_free_coherent(nvmeq->q_dmadev, SQ_SIZE(nvmeq->q_depth),
nvmeq->sq_cmds, nvmeq->sq_dma_addr);
if (nvmeq->qid)
free_cpumask_var(nvmeq->cpu_mask);
kfree(nvmeq);
}
static void nvme_free_queues(struct nvme_dev *dev, int lowest)
{
int i;
for (i = dev->queue_count - 1; i >= lowest; i--) {
struct nvme_queue *nvmeq = raw_nvmeq(dev, i);
rcu_assign_pointer(dev->queues[i], NULL);
call_rcu(&nvmeq->r_head, nvme_free_queue);
dev->queue_count--;
}
}
/**
* nvme_suspend_queue - put queue into suspended state
* @nvmeq - queue to suspend
*
* Returns 1 if already suspended, 0 otherwise.
*/
static int nvme_suspend_queue(struct nvme_queue *nvmeq)
{
int vector = nvmeq->dev->entry[nvmeq->cq_vector].vector;
spin_lock_irq(&nvmeq->q_lock);
if (nvmeq->q_suspended) {
spin_unlock_irq(&nvmeq->q_lock);
return 1;
}
nvmeq->q_suspended = 1;
nvmeq->dev->online_queues--;
spin_unlock_irq(&nvmeq->q_lock);
irq_set_affinity_hint(vector, NULL);
free_irq(vector, nvmeq);
return 0;
}
static void nvme_clear_queue(struct nvme_queue *nvmeq)
{
spin_lock_irq(&nvmeq->q_lock);
nvme_process_cq(nvmeq);
nvme_cancel_ios(nvmeq, false);
spin_unlock_irq(&nvmeq->q_lock);
}
static void nvme_disable_queue(struct nvme_dev *dev, int qid)
{
struct nvme_queue *nvmeq = raw_nvmeq(dev, qid);
if (!nvmeq)
return;
if (nvme_suspend_queue(nvmeq))
return;
/* Don't tell the adapter to delete the admin queue.
* Don't tell a removed adapter to delete IO queues. */
if (qid && readl(&dev->bar->csts) != -1) {
adapter_delete_sq(dev, qid);
adapter_delete_cq(dev, qid);
}
nvme_clear_queue(nvmeq);
}
static struct nvme_queue *nvme_alloc_queue(struct nvme_dev *dev, int qid,
int depth, int vector)
{
struct device *dmadev = &dev->pci_dev->dev;
unsigned extra = nvme_queue_extra(depth);
struct nvme_queue *nvmeq = kzalloc(sizeof(*nvmeq) + extra, GFP_KERNEL);
if (!nvmeq)
return NULL;
nvmeq->cqes = dma_alloc_coherent(dmadev, CQ_SIZE(depth),
&nvmeq->cq_dma_addr, GFP_KERNEL);
if (!nvmeq->cqes)
goto free_nvmeq;
memset((void *)nvmeq->cqes, 0, CQ_SIZE(depth));
nvmeq->sq_cmds = dma_alloc_coherent(dmadev, SQ_SIZE(depth),
&nvmeq->sq_dma_addr, GFP_KERNEL);
if (!nvmeq->sq_cmds)
goto free_cqdma;
if (qid && !zalloc_cpumask_var(&nvmeq->cpu_mask, GFP_KERNEL))
goto free_sqdma;
nvmeq->q_dmadev = dmadev;
nvmeq->dev = dev;
snprintf(nvmeq->irqname, sizeof(nvmeq->irqname), "nvme%dq%d",
dev->instance, qid);
spin_lock_init(&nvmeq->q_lock);
nvmeq->cq_head = 0;
nvmeq->cq_phase = 1;
init_waitqueue_head(&nvmeq->sq_full);
init_waitqueue_entry(&nvmeq->sq_cong_wait, nvme_thread);
bio_list_init(&nvmeq->sq_cong);
INIT_LIST_HEAD(&nvmeq->iod_bio);
nvmeq->q_db = &dev->dbs[qid * 2 * dev->db_stride];
nvmeq->q_depth = depth;
nvmeq->cq_vector = vector;
nvmeq->qid = qid;
nvmeq->q_suspended = 1;
dev->queue_count++;
rcu_assign_pointer(dev->queues[qid], nvmeq);
return nvmeq;
free_sqdma:
dma_free_coherent(dmadev, SQ_SIZE(depth), (void *)nvmeq->sq_cmds,
nvmeq->sq_dma_addr);
free_cqdma:
dma_free_coherent(dmadev, CQ_SIZE(depth), (void *)nvmeq->cqes,
nvmeq->cq_dma_addr);
free_nvmeq:
kfree(nvmeq);
return NULL;
}
static int queue_request_irq(struct nvme_dev *dev, struct nvme_queue *nvmeq,
const char *name)
{
if (use_threaded_interrupts)
return request_threaded_irq(dev->entry[nvmeq->cq_vector].vector,
nvme_irq_check, nvme_irq, IRQF_SHARED,
name, nvmeq);
return request_irq(dev->entry[nvmeq->cq_vector].vector, nvme_irq,
IRQF_SHARED, name, nvmeq);
}
static void nvme_init_queue(struct nvme_queue *nvmeq, u16 qid)
{
struct nvme_dev *dev = nvmeq->dev;
unsigned extra = nvme_queue_extra(nvmeq->q_depth);
nvmeq->sq_tail = 0;
nvmeq->cq_head = 0;
nvmeq->cq_phase = 1;
nvmeq->q_db = &dev->dbs[qid * 2 * dev->db_stride];
memset(nvmeq->cmdid_data, 0, extra);
memset((void *)nvmeq->cqes, 0, CQ_SIZE(nvmeq->q_depth));
nvme_cancel_ios(nvmeq, false);
nvmeq->q_suspended = 0;
dev->online_queues++;
}
static int nvme_create_queue(struct nvme_queue *nvmeq, int qid)
{
struct nvme_dev *dev = nvmeq->dev;
int result;
result = adapter_alloc_cq(dev, qid, nvmeq);
if (result < 0)
return result;
result = adapter_alloc_sq(dev, qid, nvmeq);
if (result < 0)
goto release_cq;
result = queue_request_irq(dev, nvmeq, nvmeq->irqname);
if (result < 0)
goto release_sq;
spin_lock_irq(&nvmeq->q_lock);
nvme_init_queue(nvmeq, qid);
spin_unlock_irq(&nvmeq->q_lock);
return result;
release_sq:
adapter_delete_sq(dev, qid);
release_cq:
adapter_delete_cq(dev, qid);
return result;
}
static int nvme_wait_ready(struct nvme_dev *dev, u64 cap, bool enabled)
{
unsigned long timeout;
u32 bit = enabled ? NVME_CSTS_RDY : 0;
timeout = ((NVME_CAP_TIMEOUT(cap) + 1) * HZ / 2) + jiffies;
while ((readl(&dev->bar->csts) & NVME_CSTS_RDY) != bit) {
msleep(100);
if (fatal_signal_pending(current))
return -EINTR;
if (time_after(jiffies, timeout)) {
dev_err(&dev->pci_dev->dev,
"Device not ready; aborting %s\n", enabled ?
"initialisation" : "reset");
return -ENODEV;
}
}
return 0;
}
/*
* If the device has been passed off to us in an enabled state, just clear
* the enabled bit. The spec says we should set the 'shutdown notification
* bits', but doing so may cause the device to complete commands to the
* admin queue ... and we don't know what memory that might be pointing at!
*/
static int nvme_disable_ctrl(struct nvme_dev *dev, u64 cap)
{
u32 cc = readl(&dev->bar->cc);
if (cc & NVME_CC_ENABLE)
writel(cc & ~NVME_CC_ENABLE, &dev->bar->cc);
return nvme_wait_ready(dev, cap, false);
}
static int nvme_enable_ctrl(struct nvme_dev *dev, u64 cap)
{
return nvme_wait_ready(dev, cap, true);
}
static int nvme_shutdown_ctrl(struct nvme_dev *dev)
{
unsigned long timeout;
u32 cc;
cc = (readl(&dev->bar->cc) & ~NVME_CC_SHN_MASK) | NVME_CC_SHN_NORMAL;
writel(cc, &dev->bar->cc);
timeout = 2 * HZ + jiffies;
while ((readl(&dev->bar->csts) & NVME_CSTS_SHST_MASK) !=
NVME_CSTS_SHST_CMPLT) {
msleep(100);
if (fatal_signal_pending(current))
return -EINTR;
if (time_after(jiffies, timeout)) {
dev_err(&dev->pci_dev->dev,
"Device shutdown incomplete; abort shutdown\n");
return -ENODEV;
}
}
return 0;
}
static int nvme_configure_admin_queue(struct nvme_dev *dev)
{
int result;
u32 aqa;
u64 cap = readq(&dev->bar->cap);
struct nvme_queue *nvmeq;
result = nvme_disable_ctrl(dev, cap);
if (result < 0)
return result;
nvmeq = raw_nvmeq(dev, 0);
if (!nvmeq) {
nvmeq = nvme_alloc_queue(dev, 0, 64, 0);
if (!nvmeq)
return -ENOMEM;
}
aqa = nvmeq->q_depth - 1;
aqa |= aqa << 16;
dev->ctrl_config = NVME_CC_ENABLE | NVME_CC_CSS_NVM;
dev->ctrl_config |= (PAGE_SHIFT - 12) << NVME_CC_MPS_SHIFT;
dev->ctrl_config |= NVME_CC_ARB_RR | NVME_CC_SHN_NONE;
dev->ctrl_config |= NVME_CC_IOSQES | NVME_CC_IOCQES;
writel(aqa, &dev->bar->aqa);
writeq(nvmeq->sq_dma_addr, &dev->bar->asq);
writeq(nvmeq->cq_dma_addr, &dev->bar->acq);
writel(dev->ctrl_config, &dev->bar->cc);
result = nvme_enable_ctrl(dev, cap);
if (result)
return result;
result = queue_request_irq(dev, nvmeq, nvmeq->irqname);
if (result)
return result;
spin_lock_irq(&nvmeq->q_lock);
nvme_init_queue(nvmeq, 0);
spin_unlock_irq(&nvmeq->q_lock);
return result;
}
struct nvme_iod *nvme_map_user_pages(struct nvme_dev *dev, int write,
unsigned long addr, unsigned length)
{
int i, err, count, nents, offset;
struct scatterlist *sg;
struct page **pages;
struct nvme_iod *iod;
if (addr & 3)
return ERR_PTR(-EINVAL);
if (!length || length > INT_MAX - PAGE_SIZE)
return ERR_PTR(-EINVAL);
offset = offset_in_page(addr);
count = DIV_ROUND_UP(offset + length, PAGE_SIZE);
pages = kcalloc(count, sizeof(*pages), GFP_KERNEL);
if (!pages)
return ERR_PTR(-ENOMEM);
err = get_user_pages_fast(addr, count, 1, pages);
if (err < count) {
count = err;
err = -EFAULT;
goto put_pages;
}
err = -ENOMEM;
iod = nvme_alloc_iod(count, length, GFP_KERNEL);
if (!iod)
goto put_pages;
sg = iod->sg;
sg_init_table(sg, count);
for (i = 0; i < count; i++) {
sg_set_page(&sg[i], pages[i],
min_t(unsigned, length, PAGE_SIZE - offset),
offset);
length -= (PAGE_SIZE - offset);
offset = 0;
}
sg_mark_end(&sg[i - 1]);
iod->nents = count;
nents = dma_map_sg(&dev->pci_dev->dev, sg, count,
write ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
if (!nents)
goto free_iod;
kfree(pages);
return iod;
free_iod:
kfree(iod);
put_pages:
for (i = 0; i < count; i++)
put_page(pages[i]);
kfree(pages);
return ERR_PTR(err);
}
void nvme_unmap_user_pages(struct nvme_dev *dev, int write,
struct nvme_iod *iod)
{
int i;
dma_unmap_sg(&dev->pci_dev->dev, iod->sg, iod->nents,
write ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
for (i = 0; i < iod->nents; i++)
put_page(sg_page(&iod->sg[i]));
}
static int nvme_submit_io(struct nvme_ns *ns, struct nvme_user_io __user *uio)
{
struct nvme_dev *dev = ns->dev;
struct nvme_user_io io;
struct nvme_command c;
unsigned length, meta_len;
int status, i;
struct nvme_iod *iod, *meta_iod = NULL;
dma_addr_t meta_dma_addr;
void *meta, *uninitialized_var(meta_mem);
if (copy_from_user(&io, uio, sizeof(io)))
return -EFAULT;
length = (io.nblocks + 1) << ns->lba_shift;
meta_len = (io.nblocks + 1) * ns->ms;
if (meta_len && ((io.metadata & 3) || !io.metadata))
return -EINVAL;
switch (io.opcode) {
case nvme_cmd_write:
case nvme_cmd_read:
case nvme_cmd_compare:
iod = nvme_map_user_pages(dev, io.opcode & 1, io.addr, length);
break;
default:
return -EINVAL;
}
if (IS_ERR(iod))
return PTR_ERR(iod);
memset(&c, 0, sizeof(c));
c.rw.opcode = io.opcode;
c.rw.flags = io.flags;
c.rw.nsid = cpu_to_le32(ns->ns_id);
c.rw.slba = cpu_to_le64(io.slba);
c.rw.length = cpu_to_le16(io.nblocks);
c.rw.control = cpu_to_le16(io.control);
c.rw.dsmgmt = cpu_to_le32(io.dsmgmt);
c.rw.reftag = cpu_to_le32(io.reftag);
c.rw.apptag = cpu_to_le16(io.apptag);
c.rw.appmask = cpu_to_le16(io.appmask);
if (meta_len) {
meta_iod = nvme_map_user_pages(dev, io.opcode & 1, io.metadata,
meta_len);
if (IS_ERR(meta_iod)) {
status = PTR_ERR(meta_iod);
meta_iod = NULL;
goto unmap;
}
meta_mem = dma_alloc_coherent(&dev->pci_dev->dev, meta_len,
&meta_dma_addr, GFP_KERNEL);
if (!meta_mem) {
status = -ENOMEM;
goto unmap;
}
if (io.opcode & 1) {
int meta_offset = 0;
for (i = 0; i < meta_iod->nents; i++) {
meta = kmap_atomic(sg_page(&meta_iod->sg[i])) +
meta_iod->sg[i].offset;
memcpy(meta_mem + meta_offset, meta,
meta_iod->sg[i].length);
kunmap_atomic(meta);
meta_offset += meta_iod->sg[i].length;
}
}
c.rw.metadata = cpu_to_le64(meta_dma_addr);
}
length = nvme_setup_prps(dev, iod, length, GFP_KERNEL);
c.rw.prp1 = cpu_to_le64(sg_dma_address(iod->sg));
c.rw.prp2 = cpu_to_le64(iod->first_dma);
if (length != (io.nblocks + 1) << ns->lba_shift)
status = -ENOMEM;
else
status = nvme_submit_io_cmd(dev, &c, NULL);
if (meta_len) {
if (status == NVME_SC_SUCCESS && !(io.opcode & 1)) {
int meta_offset = 0;
for (i = 0; i < meta_iod->nents; i++) {
meta = kmap_atomic(sg_page(&meta_iod->sg[i])) +
meta_iod->sg[i].offset;
memcpy(meta, meta_mem + meta_offset,
meta_iod->sg[i].length);
kunmap_atomic(meta);
meta_offset += meta_iod->sg[i].length;
}
}
dma_free_coherent(&dev->pci_dev->dev, meta_len, meta_mem,
meta_dma_addr);
}
unmap:
nvme_unmap_user_pages(dev, io.opcode & 1, iod);
nvme_free_iod(dev, iod);
if (meta_iod) {
nvme_unmap_user_pages(dev, io.opcode & 1, meta_iod);
nvme_free_iod(dev, meta_iod);
}
return status;
}
static int nvme_user_admin_cmd(struct nvme_dev *dev,
struct nvme_admin_cmd __user *ucmd)
{
struct nvme_admin_cmd cmd;
struct nvme_command c;
int status, length;
struct nvme_iod *uninitialized_var(iod);
unsigned timeout;
if (!capable(CAP_SYS_ADMIN))
return -EACCES;
if (copy_from_user(&cmd, ucmd, sizeof(cmd)))
return -EFAULT;
memset(&c, 0, sizeof(c));
c.common.opcode = cmd.opcode;
c.common.flags = cmd.flags;
c.common.nsid = cpu_to_le32(cmd.nsid);
c.common.cdw2[0] = cpu_to_le32(cmd.cdw2);
c.common.cdw2[1] = cpu_to_le32(cmd.cdw3);
c.common.cdw10[0] = cpu_to_le32(cmd.cdw10);
c.common.cdw10[1] = cpu_to_le32(cmd.cdw11);
c.common.cdw10[2] = cpu_to_le32(cmd.cdw12);
c.common.cdw10[3] = cpu_to_le32(cmd.cdw13);
c.common.cdw10[4] = cpu_to_le32(cmd.cdw14);
c.common.cdw10[5] = cpu_to_le32(cmd.cdw15);
length = cmd.data_len;
if (cmd.data_len) {
iod = nvme_map_user_pages(dev, cmd.opcode & 1, cmd.addr,
length);
if (IS_ERR(iod))
return PTR_ERR(iod);
length = nvme_setup_prps(dev, iod, length, GFP_KERNEL);
c.common.prp1 = cpu_to_le64(sg_dma_address(iod->sg));
c.common.prp2 = cpu_to_le64(iod->first_dma);
}
timeout = cmd.timeout_ms ? msecs_to_jiffies(cmd.timeout_ms) :
ADMIN_TIMEOUT;
if (length != cmd.data_len)
status = -ENOMEM;
else
status = nvme_submit_sync_cmd(dev, 0, &c, &cmd.result, timeout);
if (cmd.data_len) {
nvme_unmap_user_pages(dev, cmd.opcode & 1, iod);
nvme_free_iod(dev, iod);
}
if ((status >= 0) && copy_to_user(&ucmd->result, &cmd.result,
sizeof(cmd.result)))
status = -EFAULT;
return status;
}
static int nvme_ioctl(struct block_device *bdev, fmode_t mode, unsigned int cmd,
unsigned long arg)
{
struct nvme_ns *ns = bdev->bd_disk->private_data;
switch (cmd) {
case NVME_IOCTL_ID:
force_successful_syscall_return();
return ns->ns_id;
case NVME_IOCTL_ADMIN_CMD:
return nvme_user_admin_cmd(ns->dev, (void __user *)arg);
case NVME_IOCTL_SUBMIT_IO:
return nvme_submit_io(ns, (void __user *)arg);
case SG_GET_VERSION_NUM:
return nvme_sg_get_version_num((void __user *)arg);
case SG_IO:
return nvme_sg_io(ns, (void __user *)arg);
default:
return -ENOTTY;
}
}
#ifdef CONFIG_COMPAT
static int nvme_compat_ioctl(struct block_device *bdev, fmode_t mode,
unsigned int cmd, unsigned long arg)
{
struct nvme_ns *ns = bdev->bd_disk->private_data;
switch (cmd) {
case SG_IO:
return nvme_sg_io32(ns, arg);
}
return nvme_ioctl(bdev, mode, cmd, arg);
}
#else
#define nvme_compat_ioctl NULL
#endif
static int nvme_open(struct block_device *bdev, fmode_t mode)
{
struct nvme_ns *ns = bdev->bd_disk->private_data;
struct nvme_dev *dev = ns->dev;
kref_get(&dev->kref);
return 0;
}
static void nvme_free_dev(struct kref *kref);
static void nvme_release(struct gendisk *disk, fmode_t mode)
{
struct nvme_ns *ns = disk->private_data;
struct nvme_dev *dev = ns->dev;
kref_put(&dev->kref, nvme_free_dev);
}
static int nvme_getgeo(struct block_device *bd, struct hd_geometry *geo)
{
/* some standard values */
geo->heads = 1 << 6;
geo->sectors = 1 << 5;
geo->cylinders = get_capacity(bd->bd_disk) >> 11;
return 0;
}
static const struct block_device_operations nvme_fops = {
.owner = THIS_MODULE,
.ioctl = nvme_ioctl,
.compat_ioctl = nvme_compat_ioctl,
.open = nvme_open,
.release = nvme_release,
.getgeo = nvme_getgeo,
};
static void nvme_resubmit_iods(struct nvme_queue *nvmeq)
{
struct nvme_iod *iod, *next;
list_for_each_entry_safe(iod, next, &nvmeq->iod_bio, node) {
if (unlikely(nvme_submit_iod(nvmeq, iod)))
break;
list_del(&iod->node);
if (bio_list_empty(&nvmeq->sq_cong) &&
list_empty(&nvmeq->iod_bio))
remove_wait_queue(&nvmeq->sq_full,
&nvmeq->sq_cong_wait);
}
}
static void nvme_resubmit_bios(struct nvme_queue *nvmeq)
{
while (bio_list_peek(&nvmeq->sq_cong)) {
struct bio *bio = bio_list_pop(&nvmeq->sq_cong);
struct nvme_ns *ns = bio->bi_bdev->bd_disk->private_data;
if (bio_list_empty(&nvmeq->sq_cong) &&
list_empty(&nvmeq->iod_bio))
remove_wait_queue(&nvmeq->sq_full,
&nvmeq->sq_cong_wait);
if (nvme_submit_bio_queue(nvmeq, ns, bio)) {
if (!waitqueue_active(&nvmeq->sq_full))
add_wait_queue(&nvmeq->sq_full,
&nvmeq->sq_cong_wait);
bio_list_add_head(&nvmeq->sq_cong, bio);
break;
}
}
}
static int nvme_kthread(void *data)
{
struct nvme_dev *dev, *next;
while (!kthread_should_stop()) {
set_current_state(TASK_INTERRUPTIBLE);
spin_lock(&dev_list_lock);
list_for_each_entry_safe(dev, next, &dev_list, node) {
int i;
if (readl(&dev->bar->csts) & NVME_CSTS_CFS &&
dev->initialized) {
if (work_busy(&dev->reset_work))
continue;
list_del_init(&dev->node);
dev_warn(&dev->pci_dev->dev,
"Failed status, reset controller\n");
dev->reset_workfn = nvme_reset_failed_dev;
queue_work(nvme_workq, &dev->reset_work);
continue;
}
rcu_read_lock();
for (i = 0; i < dev->queue_count; i++) {
struct nvme_queue *nvmeq =
rcu_dereference(dev->queues[i]);
if (!nvmeq)
continue;
spin_lock_irq(&nvmeq->q_lock);
if (nvmeq->q_suspended)
goto unlock;
nvme_process_cq(nvmeq);
nvme_cancel_ios(nvmeq, true);
nvme_resubmit_bios(nvmeq);
nvme_resubmit_iods(nvmeq);
unlock:
spin_unlock_irq(&nvmeq->q_lock);
}
rcu_read_unlock();
}
spin_unlock(&dev_list_lock);
schedule_timeout(round_jiffies_relative(HZ));
}
return 0;
}
static void nvme_config_discard(struct nvme_ns *ns)
{
u32 logical_block_size = queue_logical_block_size(ns->queue);
ns->queue->limits.discard_zeroes_data = 0;
ns->queue->limits.discard_alignment = logical_block_size;
ns->queue->limits.discard_granularity = logical_block_size;
ns->queue->limits.max_discard_sectors = 0xffffffff;
queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, ns->queue);
}
static struct nvme_ns *nvme_alloc_ns(struct nvme_dev *dev, unsigned nsid,
struct nvme_id_ns *id, struct nvme_lba_range_type *rt)
{
struct nvme_ns *ns;
struct gendisk *disk;
int lbaf;
if (rt->attributes & NVME_LBART_ATTRIB_HIDE)
return NULL;
ns = kzalloc(sizeof(*ns), GFP_KERNEL);
if (!ns)
return NULL;
ns->queue = blk_alloc_queue(GFP_KERNEL);
if (!ns->queue)
goto out_free_ns;
ns->queue->queue_flags = QUEUE_FLAG_DEFAULT;
queue_flag_set_unlocked(QUEUE_FLAG_NOMERGES, ns->queue);
queue_flag_set_unlocked(QUEUE_FLAG_NONROT, ns->queue);
blk_queue_make_request(ns->queue, nvme_make_request);
ns->dev = dev;
ns->queue->queuedata = ns;
disk = alloc_disk(0);
if (!disk)
goto out_free_queue;
ns->ns_id = nsid;
ns->disk = disk;
lbaf = id->flbas & 0xf;
ns->lba_shift = id->lbaf[lbaf].ds;
ns->ms = le16_to_cpu(id->lbaf[lbaf].ms);
blk_queue_logical_block_size(ns->queue, 1 << ns->lba_shift);
if (dev->max_hw_sectors)
blk_queue_max_hw_sectors(ns->queue, dev->max_hw_sectors);
if (dev->vwc & NVME_CTRL_VWC_PRESENT)
blk_queue_flush(ns->queue, REQ_FLUSH | REQ_FUA);
disk->major = nvme_major;
disk->first_minor = 0;
disk->fops = &nvme_fops;
disk->private_data = ns;
disk->queue = ns->queue;
disk->driverfs_dev = &dev->pci_dev->dev;
disk->flags = GENHD_FL_EXT_DEVT;
sprintf(disk->disk_name, "nvme%dn%d", dev->instance, nsid);
set_capacity(disk, le64_to_cpup(&id->nsze) << (ns->lba_shift - 9));
if (dev->oncs & NVME_CTRL_ONCS_DSM)
nvme_config_discard(ns);
return ns;
out_free_queue:
blk_cleanup_queue(ns->queue);
out_free_ns:
kfree(ns);
return NULL;
}
static int nvme_find_closest_node(int node)
{
int n, val, min_val = INT_MAX, best_node = node;
for_each_online_node(n) {
if (n == node)
continue;
val = node_distance(node, n);
if (val < min_val) {
min_val = val;
best_node = n;
}
}
return best_node;
}
static void nvme_set_queue_cpus(cpumask_t *qmask, struct nvme_queue *nvmeq,
int count)
{
int cpu;
for_each_cpu(cpu, qmask) {
if (cpumask_weight(nvmeq->cpu_mask) >= count)
break;
if (!cpumask_test_and_set_cpu(cpu, nvmeq->cpu_mask))
*per_cpu_ptr(nvmeq->dev->io_queue, cpu) = nvmeq->qid;
}
}
static void nvme_add_cpus(cpumask_t *mask, const cpumask_t *unassigned_cpus,
const cpumask_t *new_mask, struct nvme_queue *nvmeq, int cpus_per_queue)
{
int next_cpu;
for_each_cpu(next_cpu, new_mask) {
cpumask_or(mask, mask, get_cpu_mask(next_cpu));
cpumask_or(mask, mask, topology_thread_cpumask(next_cpu));
cpumask_and(mask, mask, unassigned_cpus);
nvme_set_queue_cpus(mask, nvmeq, cpus_per_queue);
}
}
static void nvme_create_io_queues(struct nvme_dev *dev)
{
unsigned i, max;
max = min(dev->max_qid, num_online_cpus());
for (i = dev->queue_count; i <= max; i++)
if (!nvme_alloc_queue(dev, i, dev->q_depth, i - 1))
break;
max = min(dev->queue_count - 1, num_online_cpus());
for (i = dev->online_queues; i <= max; i++)
if (nvme_create_queue(raw_nvmeq(dev, i), i))
break;
}
/*
* If there are fewer queues than online cpus, this will try to optimally
* assign a queue to multiple cpus by grouping cpus that are "close" together:
* thread siblings, core, socket, closest node, then whatever else is
* available.
*/
static void nvme_assign_io_queues(struct nvme_dev *dev)
{
unsigned cpu, cpus_per_queue, queues, remainder, i;
cpumask_var_t unassigned_cpus;
nvme_create_io_queues(dev);
queues = min(dev->online_queues - 1, num_online_cpus());
if (!queues)
return;
cpus_per_queue = num_online_cpus() / queues;
remainder = queues - (num_online_cpus() - queues * cpus_per_queue);
if (!alloc_cpumask_var(&unassigned_cpus, GFP_KERNEL))
return;
cpumask_copy(unassigned_cpus, cpu_online_mask);
cpu = cpumask_first(unassigned_cpus);
for (i = 1; i <= queues; i++) {
struct nvme_queue *nvmeq = lock_nvmeq(dev, i);
cpumask_t mask;
cpumask_clear(nvmeq->cpu_mask);
if (!cpumask_weight(unassigned_cpus)) {
unlock_nvmeq(nvmeq);
break;
}
mask = *get_cpu_mask(cpu);
nvme_set_queue_cpus(&mask, nvmeq, cpus_per_queue);
if (cpus_weight(mask) < cpus_per_queue)
nvme_add_cpus(&mask, unassigned_cpus,
topology_thread_cpumask(cpu),
nvmeq, cpus_per_queue);
if (cpus_weight(mask) < cpus_per_queue)
nvme_add_cpus(&mask, unassigned_cpus,
topology_core_cpumask(cpu),
nvmeq, cpus_per_queue);
if (cpus_weight(mask) < cpus_per_queue)
nvme_add_cpus(&mask, unassigned_cpus,
cpumask_of_node(cpu_to_node(cpu)),
nvmeq, cpus_per_queue);
if (cpus_weight(mask) < cpus_per_queue)
nvme_add_cpus(&mask, unassigned_cpus,
cpumask_of_node(
nvme_find_closest_node(
cpu_to_node(cpu))),
nvmeq, cpus_per_queue);
if (cpus_weight(mask) < cpus_per_queue)
nvme_add_cpus(&mask, unassigned_cpus,
unassigned_cpus,
nvmeq, cpus_per_queue);
WARN(cpumask_weight(nvmeq->cpu_mask) != cpus_per_queue,
"nvme%d qid:%d mis-matched queue-to-cpu assignment\n",
dev->instance, i);
irq_set_affinity_hint(dev->entry[nvmeq->cq_vector].vector,
nvmeq->cpu_mask);
cpumask_andnot(unassigned_cpus, unassigned_cpus,
nvmeq->cpu_mask);
cpu = cpumask_next(cpu, unassigned_cpus);
if (remainder && !--remainder)
cpus_per_queue++;
unlock_nvmeq(nvmeq);
}
WARN(cpumask_weight(unassigned_cpus), "nvme%d unassigned online cpus\n",
dev->instance);
i = 0;
cpumask_andnot(unassigned_cpus, cpu_possible_mask, cpu_online_mask);
for_each_cpu(cpu, unassigned_cpus)
*per_cpu_ptr(dev->io_queue, cpu) = (i++ % queues) + 1;
free_cpumask_var(unassigned_cpus);
}
static int set_queue_count(struct nvme_dev *dev, int count)
{
int status;
u32 result;
u32 q_count = (count - 1) | ((count - 1) << 16);
status = nvme_set_features(dev, NVME_FEAT_NUM_QUEUES, q_count, 0,
&result);
if (status < 0)
return status;
if (status > 0) {
dev_err(&dev->pci_dev->dev, "Could not set queue count (%d)\n",
status);
return -EBUSY;
}
return min(result & 0xffff, result >> 16) + 1;
}
static size_t db_bar_size(struct nvme_dev *dev, unsigned nr_io_queues)
{
return 4096 + ((nr_io_queues + 1) * 8 * dev->db_stride);
}
static void nvme_cpu_workfn(struct work_struct *work)
{
struct nvme_dev *dev = container_of(work, struct nvme_dev, cpu_work);
if (dev->initialized)
nvme_assign_io_queues(dev);
}
static int nvme_cpu_notify(struct notifier_block *self,
unsigned long action, void *hcpu)
{
struct nvme_dev *dev;
switch (action) {
case CPU_ONLINE:
case CPU_DEAD:
spin_lock(&dev_list_lock);
list_for_each_entry(dev, &dev_list, node)
schedule_work(&dev->cpu_work);
spin_unlock(&dev_list_lock);
break;
}
return NOTIFY_OK;
}
static int nvme_setup_io_queues(struct nvme_dev *dev)
{
struct nvme_queue *adminq = raw_nvmeq(dev, 0);
struct pci_dev *pdev = dev->pci_dev;
int result, i, vecs, nr_io_queues, size;
nr_io_queues = num_possible_cpus();
result = set_queue_count(dev, nr_io_queues);
if (result < 0)
return result;
if (result < nr_io_queues)
nr_io_queues = result;
size = db_bar_size(dev, nr_io_queues);
if (size > 8192) {
iounmap(dev->bar);
do {
dev->bar = ioremap(pci_resource_start(pdev, 0), size);
if (dev->bar)
break;
if (!--nr_io_queues)
return -ENOMEM;
size = db_bar_size(dev, nr_io_queues);
} while (1);
dev->dbs = ((void __iomem *)dev->bar) + 4096;
adminq->q_db = dev->dbs;
}
/* Deregister the admin queue's interrupt */
free_irq(dev->entry[0].vector, adminq);
for (i = 0; i < nr_io_queues; i++)
dev->entry[i].entry = i;
vecs = pci_enable_msix_range(pdev, dev->entry, 1, nr_io_queues);
if (vecs < 0) {
vecs = pci_enable_msi_range(pdev, 1, min(nr_io_queues, 32));
if (vecs < 0) {
vecs = 1;
} else {
for (i = 0; i < vecs; i++)
dev->entry[i].vector = i + pdev->irq;
}
}
/*
* Should investigate if there's a performance win from allocating
* more queues than interrupt vectors; it might allow the submission
* path to scale better, even if the receive path is limited by the
* number of interrupts.
*/
nr_io_queues = vecs;
dev->max_qid = nr_io_queues;
result = queue_request_irq(dev, adminq, adminq->irqname);
if (result) {
adminq->q_suspended = 1;
goto free_queues;
}
/* Free previously allocated queues that are no longer usable */
nvme_free_queues(dev, nr_io_queues + 1);
nvme_assign_io_queues(dev);
return 0;
free_queues:
nvme_free_queues(dev, 1);
return result;
}
/*
* Return: error value if an error occurred setting up the queues or calling
* Identify Device. 0 if these succeeded, even if adding some of the
* namespaces failed. At the moment, these failures are silent. TBD which
* failures should be reported.
*/
static int nvme_dev_add(struct nvme_dev *dev)
{
struct pci_dev *pdev = dev->pci_dev;
int res;
unsigned nn, i;
struct nvme_ns *ns;
struct nvme_id_ctrl *ctrl;
struct nvme_id_ns *id_ns;
void *mem;
dma_addr_t dma_addr;
int shift = NVME_CAP_MPSMIN(readq(&dev->bar->cap)) + 12;
mem = dma_alloc_coherent(&pdev->dev, 8192, &dma_addr, GFP_KERNEL);
if (!mem)
return -ENOMEM;
res = nvme_identify(dev, 0, 1, dma_addr);
if (res) {
dev_err(&pdev->dev, "Identify Controller failed (%d)\n", res);
res = -EIO;
goto out;
}
ctrl = mem;
nn = le32_to_cpup(&ctrl->nn);
dev->oncs = le16_to_cpup(&ctrl->oncs);
dev->abort_limit = ctrl->acl + 1;
dev->vwc = ctrl->vwc;
memcpy(dev->serial, ctrl->sn, sizeof(ctrl->sn));
memcpy(dev->model, ctrl->mn, sizeof(ctrl->mn));
memcpy(dev->firmware_rev, ctrl->fr, sizeof(ctrl->fr));
if (ctrl->mdts)
dev->max_hw_sectors = 1 << (ctrl->mdts + shift - 9);
if ((pdev->vendor == PCI_VENDOR_ID_INTEL) &&
(pdev->device == 0x0953) && ctrl->vs[3])
dev->stripe_size = 1 << (ctrl->vs[3] + shift);
id_ns = mem;
for (i = 1; i <= nn; i++) {
res = nvme_identify(dev, i, 0, dma_addr);
if (res)
continue;
if (id_ns->ncap == 0)
continue;
res = nvme_get_features(dev, NVME_FEAT_LBA_RANGE, i,
dma_addr + 4096, NULL);
if (res)
memset(mem + 4096, 0, 4096);
ns = nvme_alloc_ns(dev, i, mem, mem + 4096);
if (ns)
list_add_tail(&ns->list, &dev->namespaces);
}
list_for_each_entry(ns, &dev->namespaces, list)
add_disk(ns->disk);
res = 0;
out:
dma_free_coherent(&dev->pci_dev->dev, 8192, mem, dma_addr);
return res;
}
static int nvme_dev_map(struct nvme_dev *dev)
{
u64 cap;
int bars, result = -ENOMEM;
struct pci_dev *pdev = dev->pci_dev;
if (pci_enable_device_mem(pdev))
return result;
dev->entry[0].vector = pdev->irq;
pci_set_master(pdev);
bars = pci_select_bars(pdev, IORESOURCE_MEM);
if (pci_request_selected_regions(pdev, bars, "nvme"))
goto disable_pci;
if (dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64)) &&
dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32)))
goto disable;
dev->bar = ioremap(pci_resource_start(pdev, 0), 8192);
if (!dev->bar)
goto disable;
if (readl(&dev->bar->csts) == -1) {
result = -ENODEV;
goto unmap;
}
cap = readq(&dev->bar->cap);
dev->q_depth = min_t(int, NVME_CAP_MQES(cap) + 1, NVME_Q_DEPTH);
dev->db_stride = 1 << NVME_CAP_STRIDE(cap);
dev->dbs = ((void __iomem *)dev->bar) + 4096;
return 0;
unmap:
iounmap(dev->bar);
dev->bar = NULL;
disable:
pci_release_regions(pdev);
disable_pci:
pci_disable_device(pdev);
return result;
}
static void nvme_dev_unmap(struct nvme_dev *dev)
{
if (dev->pci_dev->msi_enabled)
pci_disable_msi(dev->pci_dev);
else if (dev->pci_dev->msix_enabled)
pci_disable_msix(dev->pci_dev);
if (dev->bar) {
iounmap(dev->bar);
dev->bar = NULL;
pci_release_regions(dev->pci_dev);
}
if (pci_is_enabled(dev->pci_dev))
pci_disable_device(dev->pci_dev);
}
struct nvme_delq_ctx {
struct task_struct *waiter;
struct kthread_worker *worker;
atomic_t refcount;
};
static void nvme_wait_dq(struct nvme_delq_ctx *dq, struct nvme_dev *dev)
{
dq->waiter = current;
mb();
for (;;) {
set_current_state(TASK_KILLABLE);
if (!atomic_read(&dq->refcount))
break;
if (!schedule_timeout(ADMIN_TIMEOUT) ||
fatal_signal_pending(current)) {
set_current_state(TASK_RUNNING);
nvme_disable_ctrl(dev, readq(&dev->bar->cap));
nvme_disable_queue(dev, 0);
send_sig(SIGKILL, dq->worker->task, 1);
flush_kthread_worker(dq->worker);
return;
}
}
set_current_state(TASK_RUNNING);
}
static void nvme_put_dq(struct nvme_delq_ctx *dq)
{
atomic_dec(&dq->refcount);
if (dq->waiter)
wake_up_process(dq->waiter);
}
static struct nvme_delq_ctx *nvme_get_dq(struct nvme_delq_ctx *dq)
{
atomic_inc(&dq->refcount);
return dq;
}
static void nvme_del_queue_end(struct nvme_queue *nvmeq)
{
struct nvme_delq_ctx *dq = nvmeq->cmdinfo.ctx;
nvme_clear_queue(nvmeq);
nvme_put_dq(dq);
}
static int adapter_async_del_queue(struct nvme_queue *nvmeq, u8 opcode,
kthread_work_func_t fn)
{
struct nvme_command c;
memset(&c, 0, sizeof(c));
c.delete_queue.opcode = opcode;
c.delete_queue.qid = cpu_to_le16(nvmeq->qid);
init_kthread_work(&nvmeq->cmdinfo.work, fn);
return nvme_submit_admin_cmd_async(nvmeq->dev, &c, &nvmeq->cmdinfo);
}
static void nvme_del_cq_work_handler(struct kthread_work *work)
{
struct nvme_queue *nvmeq = container_of(work, struct nvme_queue,
cmdinfo.work);
nvme_del_queue_end(nvmeq);
}
static int nvme_delete_cq(struct nvme_queue *nvmeq)
{
return adapter_async_del_queue(nvmeq, nvme_admin_delete_cq,
nvme_del_cq_work_handler);
}
static void nvme_del_sq_work_handler(struct kthread_work *work)
{
struct nvme_queue *nvmeq = container_of(work, struct nvme_queue,
cmdinfo.work);
int status = nvmeq->cmdinfo.status;
if (!status)
status = nvme_delete_cq(nvmeq);
if (status)
nvme_del_queue_end(nvmeq);
}
static int nvme_delete_sq(struct nvme_queue *nvmeq)
{
return adapter_async_del_queue(nvmeq, nvme_admin_delete_sq,
nvme_del_sq_work_handler);
}
static void nvme_del_queue_start(struct kthread_work *work)
{
struct nvme_queue *nvmeq = container_of(work, struct nvme_queue,
cmdinfo.work);
allow_signal(SIGKILL);
if (nvme_delete_sq(nvmeq))
nvme_del_queue_end(nvmeq);
}
static void nvme_disable_io_queues(struct nvme_dev *dev)
{
int i;
DEFINE_KTHREAD_WORKER_ONSTACK(worker);
struct nvme_delq_ctx dq;
struct task_struct *kworker_task = kthread_run(kthread_worker_fn,
&worker, "nvme%d", dev->instance);
if (IS_ERR(kworker_task)) {
dev_err(&dev->pci_dev->dev,
"Failed to create queue del task\n");
for (i = dev->queue_count - 1; i > 0; i--)
nvme_disable_queue(dev, i);
return;
}
dq.waiter = NULL;
atomic_set(&dq.refcount, 0);
dq.worker = &worker;
for (i = dev->queue_count - 1; i > 0; i--) {
struct nvme_queue *nvmeq = raw_nvmeq(dev, i);
if (nvme_suspend_queue(nvmeq))
continue;
nvmeq->cmdinfo.ctx = nvme_get_dq(&dq);
nvmeq->cmdinfo.worker = dq.worker;
init_kthread_work(&nvmeq->cmdinfo.work, nvme_del_queue_start);
queue_kthread_work(dq.worker, &nvmeq->cmdinfo.work);
}
nvme_wait_dq(&dq, dev);
kthread_stop(kworker_task);
}
/*
* Remove the node from the device list and check
* for whether or not we need to stop the nvme_thread.
*/
static void nvme_dev_list_remove(struct nvme_dev *dev)
{
struct task_struct *tmp = NULL;
spin_lock(&dev_list_lock);
list_del_init(&dev->node);
if (list_empty(&dev_list) && !IS_ERR_OR_NULL(nvme_thread)) {
tmp = nvme_thread;
nvme_thread = NULL;
}
spin_unlock(&dev_list_lock);
if (tmp)
kthread_stop(tmp);
}
static void nvme_dev_shutdown(struct nvme_dev *dev)
{
int i;
dev->initialized = 0;
nvme_dev_list_remove(dev);
if (!dev->bar || (dev->bar && readl(&dev->bar->csts) == -1)) {
for (i = dev->queue_count - 1; i >= 0; i--) {
struct nvme_queue *nvmeq = raw_nvmeq(dev, i);
nvme_suspend_queue(nvmeq);
nvme_clear_queue(nvmeq);
}
} else {
nvme_disable_io_queues(dev);
nvme_shutdown_ctrl(dev);
nvme_disable_queue(dev, 0);
}
nvme_dev_unmap(dev);
}
static void nvme_dev_remove(struct nvme_dev *dev)
{
struct nvme_ns *ns;
list_for_each_entry(ns, &dev->namespaces, list) {
if (ns->disk->flags & GENHD_FL_UP)
del_gendisk(ns->disk);
if (!blk_queue_dying(ns->queue))
blk_cleanup_queue(ns->queue);
}
}
static int nvme_setup_prp_pools(struct nvme_dev *dev)
{
struct device *dmadev = &dev->pci_dev->dev;
dev->prp_page_pool = dma_pool_create("prp list page", dmadev,
PAGE_SIZE, PAGE_SIZE, 0);
if (!dev->prp_page_pool)
return -ENOMEM;
/* Optimisation for I/Os between 4k and 128k */
dev->prp_small_pool = dma_pool_create("prp list 256", dmadev,
256, 256, 0);
if (!dev->prp_small_pool) {
dma_pool_destroy(dev->prp_page_pool);
return -ENOMEM;
}
return 0;
}
static void nvme_release_prp_pools(struct nvme_dev *dev)
{
dma_pool_destroy(dev->prp_page_pool);
dma_pool_destroy(dev->prp_small_pool);
}
static DEFINE_IDA(nvme_instance_ida);
static int nvme_set_instance(struct nvme_dev *dev)
{
int instance, error;
do {
if (!ida_pre_get(&nvme_instance_ida, GFP_KERNEL))
return -ENODEV;
spin_lock(&dev_list_lock);
error = ida_get_new(&nvme_instance_ida, &instance);
spin_unlock(&dev_list_lock);
} while (error == -EAGAIN);
if (error)
return -ENODEV;
dev->instance = instance;
return 0;
}
static void nvme_release_instance(struct nvme_dev *dev)
{
spin_lock(&dev_list_lock);
ida_remove(&nvme_instance_ida, dev->instance);
spin_unlock(&dev_list_lock);
}
static void nvme_free_namespaces(struct nvme_dev *dev)
{
struct nvme_ns *ns, *next;
list_for_each_entry_safe(ns, next, &dev->namespaces, list) {
list_del(&ns->list);
put_disk(ns->disk);
kfree(ns);
}
}
static void nvme_free_dev(struct kref *kref)
{
struct nvme_dev *dev = container_of(kref, struct nvme_dev, kref);
nvme_free_namespaces(dev);
free_percpu(dev->io_queue);
kfree(dev->queues);
kfree(dev->entry);
kfree(dev);
}
static int nvme_dev_open(struct inode *inode, struct file *f)
{
struct nvme_dev *dev = container_of(f->private_data, struct nvme_dev,
miscdev);
kref_get(&dev->kref);
f->private_data = dev;
return 0;
}
static int nvme_dev_release(struct inode *inode, struct file *f)
{
struct nvme_dev *dev = f->private_data;
kref_put(&dev->kref, nvme_free_dev);
return 0;
}
static long nvme_dev_ioctl(struct file *f, unsigned int cmd, unsigned long arg)
{
struct nvme_dev *dev = f->private_data;
switch (cmd) {
case NVME_IOCTL_ADMIN_CMD:
return nvme_user_admin_cmd(dev, (void __user *)arg);
default:
return -ENOTTY;
}
}
static const struct file_operations nvme_dev_fops = {
.owner = THIS_MODULE,
.open = nvme_dev_open,
.release = nvme_dev_release,
.unlocked_ioctl = nvme_dev_ioctl,
.compat_ioctl = nvme_dev_ioctl,
};
static int nvme_dev_start(struct nvme_dev *dev)
{
int result;
bool start_thread = false;
result = nvme_dev_map(dev);
if (result)
return result;
result = nvme_configure_admin_queue(dev);
if (result)
goto unmap;
spin_lock(&dev_list_lock);
if (list_empty(&dev_list) && IS_ERR_OR_NULL(nvme_thread)) {
start_thread = true;
nvme_thread = NULL;
}
list_add(&dev->node, &dev_list);
spin_unlock(&dev_list_lock);
if (start_thread) {
nvme_thread = kthread_run(nvme_kthread, NULL, "nvme");
wake_up(&nvme_kthread_wait);
} else
wait_event_killable(nvme_kthread_wait, nvme_thread);
if (IS_ERR_OR_NULL(nvme_thread)) {
result = nvme_thread ? PTR_ERR(nvme_thread) : -EINTR;
goto disable;
}
result = nvme_setup_io_queues(dev);
if (result && result != -EBUSY)
goto disable;
return result;
disable:
nvme_disable_queue(dev, 0);
nvme_dev_list_remove(dev);
unmap:
nvme_dev_unmap(dev);
return result;
}
static int nvme_remove_dead_ctrl(void *arg)
{
struct nvme_dev *dev = (struct nvme_dev *)arg;
struct pci_dev *pdev = dev->pci_dev;
if (pci_get_drvdata(pdev))
pci_stop_and_remove_bus_device(pdev);
kref_put(&dev->kref, nvme_free_dev);
return 0;
}
static void nvme_remove_disks(struct work_struct *ws)
{
struct nvme_dev *dev = container_of(ws, struct nvme_dev, reset_work);
nvme_dev_remove(dev);
nvme_free_queues(dev, 1);
}
static int nvme_dev_resume(struct nvme_dev *dev)
{
int ret;
ret = nvme_dev_start(dev);
if (ret && ret != -EBUSY)
return ret;
if (ret == -EBUSY) {
spin_lock(&dev_list_lock);
dev->reset_workfn = nvme_remove_disks;
queue_work(nvme_workq, &dev->reset_work);
spin_unlock(&dev_list_lock);
}
dev->initialized = 1;
return 0;
}
static void nvme_dev_reset(struct nvme_dev *dev)
{
nvme_dev_shutdown(dev);
if (nvme_dev_resume(dev)) {
dev_err(&dev->pci_dev->dev, "Device failed to resume\n");
kref_get(&dev->kref);
if (IS_ERR(kthread_run(nvme_remove_dead_ctrl, dev, "nvme%d",
dev->instance))) {
dev_err(&dev->pci_dev->dev,
"Failed to start controller remove task\n");
kref_put(&dev->kref, nvme_free_dev);
}
}
}
static void nvme_reset_failed_dev(struct work_struct *ws)
{
struct nvme_dev *dev = container_of(ws, struct nvme_dev, reset_work);
nvme_dev_reset(dev);
}
static void nvme_reset_workfn(struct work_struct *work)
{
struct nvme_dev *dev = container_of(work, struct nvme_dev, reset_work);
dev->reset_workfn(work);
}
static int nvme_probe(struct pci_dev *pdev, const struct pci_device_id *id)
{
int result = -ENOMEM;
struct nvme_dev *dev;
dev = kzalloc(sizeof(*dev), GFP_KERNEL);
if (!dev)
return -ENOMEM;
dev->entry = kcalloc(num_possible_cpus(), sizeof(*dev->entry),
GFP_KERNEL);
if (!dev->entry)
goto free;
dev->queues = kcalloc(num_possible_cpus() + 1, sizeof(void *),
GFP_KERNEL);
if (!dev->queues)
goto free;
dev->io_queue = alloc_percpu(unsigned short);
if (!dev->io_queue)
goto free;
INIT_LIST_HEAD(&dev->namespaces);
dev->reset_workfn = nvme_reset_failed_dev;
INIT_WORK(&dev->reset_work, nvme_reset_workfn);
INIT_WORK(&dev->cpu_work, nvme_cpu_workfn);
dev->pci_dev = pdev;
pci_set_drvdata(pdev, dev);
result = nvme_set_instance(dev);
if (result)
goto free;
result = nvme_setup_prp_pools(dev);
if (result)
goto release;
kref_init(&dev->kref);
result = nvme_dev_start(dev);
if (result) {
if (result == -EBUSY)
goto create_cdev;
goto release_pools;
}
result = nvme_dev_add(dev);
if (result)
goto shutdown;
create_cdev:
scnprintf(dev->name, sizeof(dev->name), "nvme%d", dev->instance);
dev->miscdev.minor = MISC_DYNAMIC_MINOR;
dev->miscdev.parent = &pdev->dev;
dev->miscdev.name = dev->name;
dev->miscdev.fops = &nvme_dev_fops;
result = misc_register(&dev->miscdev);
if (result)
goto remove;
dev->initialized = 1;
return 0;
remove:
nvme_dev_remove(dev);
nvme_free_namespaces(dev);
shutdown:
nvme_dev_shutdown(dev);
release_pools:
nvme_free_queues(dev, 0);
nvme_release_prp_pools(dev);
release:
nvme_release_instance(dev);
free:
free_percpu(dev->io_queue);
kfree(dev->queues);
kfree(dev->entry);
kfree(dev);
return result;
}
static void nvme_reset_notify(struct pci_dev *pdev, bool prepare)
{
struct nvme_dev *dev = pci_get_drvdata(pdev);
if (prepare)
nvme_dev_shutdown(dev);
else
nvme_dev_resume(dev);
}
static void nvme_shutdown(struct pci_dev *pdev)
{
struct nvme_dev *dev = pci_get_drvdata(pdev);
nvme_dev_shutdown(dev);
}
static void nvme_remove(struct pci_dev *pdev)
{
struct nvme_dev *dev = pci_get_drvdata(pdev);
spin_lock(&dev_list_lock);
list_del_init(&dev->node);
spin_unlock(&dev_list_lock);
pci_set_drvdata(pdev, NULL);
flush_work(&dev->reset_work);
flush_work(&dev->cpu_work);
misc_deregister(&dev->miscdev);
nvme_dev_remove(dev);
nvme_dev_shutdown(dev);
nvme_free_queues(dev, 0);
rcu_barrier();
nvme_release_instance(dev);
nvme_release_prp_pools(dev);
kref_put(&dev->kref, nvme_free_dev);
}
/* These functions are yet to be implemented */
#define nvme_error_detected NULL
#define nvme_dump_registers NULL
#define nvme_link_reset NULL
#define nvme_slot_reset NULL
#define nvme_error_resume NULL
#ifdef CONFIG_PM_SLEEP
static int nvme_suspend(struct device *dev)
{
struct pci_dev *pdev = to_pci_dev(dev);
struct nvme_dev *ndev = pci_get_drvdata(pdev);
nvme_dev_shutdown(ndev);
return 0;
}
static int nvme_resume(struct device *dev)
{
struct pci_dev *pdev = to_pci_dev(dev);
struct nvme_dev *ndev = pci_get_drvdata(pdev);
if (nvme_dev_resume(ndev) && !work_busy(&ndev->reset_work)) {
ndev->reset_workfn = nvme_reset_failed_dev;
queue_work(nvme_workq, &ndev->reset_work);
}
return 0;
}
#endif
static SIMPLE_DEV_PM_OPS(nvme_dev_pm_ops, nvme_suspend, nvme_resume);
static const struct pci_error_handlers nvme_err_handler = {
.error_detected = nvme_error_detected,
.mmio_enabled = nvme_dump_registers,
.link_reset = nvme_link_reset,
.slot_reset = nvme_slot_reset,
.resume = nvme_error_resume,
.reset_notify = nvme_reset_notify,
};
/* Move to pci_ids.h later */
#define PCI_CLASS_STORAGE_EXPRESS 0x010802
static const struct pci_device_id nvme_id_table[] = {
{ PCI_DEVICE_CLASS(PCI_CLASS_STORAGE_EXPRESS, 0xffffff) },
{ 0, }
};
MODULE_DEVICE_TABLE(pci, nvme_id_table);
static struct pci_driver nvme_driver = {
.name = "nvme",
.id_table = nvme_id_table,
.probe = nvme_probe,
.remove = nvme_remove,
.shutdown = nvme_shutdown,
.driver = {
.pm = &nvme_dev_pm_ops,
},
.err_handler = &nvme_err_handler,
};
static int __init nvme_init(void)
{
int result;
init_waitqueue_head(&nvme_kthread_wait);
nvme_workq = create_singlethread_workqueue("nvme");
if (!nvme_workq)
return -ENOMEM;
result = register_blkdev(nvme_major, "nvme");
if (result < 0)
goto kill_workq;
else if (result > 0)
nvme_major = result;
nvme_nb.notifier_call = &nvme_cpu_notify;
result = register_hotcpu_notifier(&nvme_nb);
if (result)
goto unregister_blkdev;
result = pci_register_driver(&nvme_driver);
if (result)
goto unregister_hotcpu;
return 0;
unregister_hotcpu:
unregister_hotcpu_notifier(&nvme_nb);
unregister_blkdev:
unregister_blkdev(nvme_major, "nvme");
kill_workq:
destroy_workqueue(nvme_workq);
return result;
}
static void __exit nvme_exit(void)
{
pci_unregister_driver(&nvme_driver);
unregister_hotcpu_notifier(&nvme_nb);
unregister_blkdev(nvme_major, "nvme");
destroy_workqueue(nvme_workq);
BUG_ON(nvme_thread && !IS_ERR(nvme_thread));
_nvme_check_size();
}
MODULE_AUTHOR("Matthew Wilcox <willy@linux.intel.com>");
MODULE_LICENSE("GPL");
MODULE_VERSION("0.9");
module_init(nvme_init);
module_exit(nvme_exit);