microsoft
/
WSL2-Linux-Kernel
зеркало из https://github.com/microsoft/WSL2-Linux-Kernel.git
1
0
Форкнуть 0
Код Задачи Пакеты Проекты Релизы Вики Активность
WSL2-Linux-Kernel/drivers/block/nvme-core.c

2327 строки
56 KiB
C
Исходник Ответственный История

/*
* NVM Express device driver
* Copyright (c) 2011, 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.
*
* You should have received a copy of the GNU General Public License along with
* this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include <linux/nvme.h>
#include <linux/bio.h>
#include <linux/bitops.h>
#include <linux/blkdev.h>
#include <linux/delay.h>
#include <linux/errno.h>
#include <linux/fs.h>
#include <linux/genhd.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/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>
#define NVME_Q_DEPTH 1024
#define SQ_SIZE(depth) (depth * sizeof(struct nvme_command))
#define CQ_SIZE(depth) (depth * sizeof(struct nvme_completion))
#define NVME_MINORS 64
#define ADMIN_TIMEOUT (60 * HZ)
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;
/*
* An NVM Express queue. Each device has at least two (one for admin
* commands and one for I/O commands).
*/
struct nvme_queue {
struct device *q_dmadev;
struct nvme_dev *dev;
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;
u32 __iomem *q_db;
u16 q_depth;
u16 cq_vector;
u16 sq_head;
u16 sq_tail;
u16 cq_head;
u8 cq_phase;
u8 cqe_seen;
u8 q_suspended;
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_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_dev *, void *,
struct nvme_completion *);
struct nvme_cmd_info {
nvme_completion_fn fn;
void *ctx;
unsigned long timeout;
};
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;
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_FLUSH (0x318 + CMD_CTX_BASE)
static void special_completion(struct nvme_dev *dev, void *ctx,
struct nvme_completion *cqe)
{
if (ctx == CMD_CTX_CANCELLED)
return;
if (ctx == CMD_CTX_FLUSH)
return;
if (ctx == CMD_CTX_COMPLETED) {
dev_warn(&dev->pci_dev->dev,
"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(&dev->pci_dev->dev,
"invalid id %d completed on queue %d\n",
cqe->command_id, le16_to_cpup(&cqe->sq_id));
return;
}
dev_warn(&dev->pci_dev->dev, "Unknown special completion %p\n", ctx);
}
/*
* 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) {
*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;
}
struct nvme_queue *get_nvmeq(struct nvme_dev *dev)
{
return dev->queues[get_cpu() + 1];
}
void put_nvmeq(struct nvme_queue *nvmeq)
{
put_cpu();
}
/**
* 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);
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->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;
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;
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_dev *dev, void *ctx,
struct nvme_completion *cqe)
{
struct nvme_iod *iod = ctx;
struct bio *bio = iod->private;
u16 status = le16_to_cpup(&cqe->status) >> 1;
if (iod->nents) {
dma_unmap_sg(&dev->pci_dev->dev, 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(dev, iod);
if (status)
bio_endio(bio, -EIO);
else
bio_endio(bio, 0);
}
/* length is in bytes. gfp flags indicates whether we may sleep. */
int nvme_setup_prps(struct nvme_dev *dev, struct nvme_common_command *cmd,
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;
cmd->prp1 = cpu_to_le64(dma_addr);
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) {
cmd->prp2 = cpu_to_le64(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) {
cmd->prp2 = cpu_to_le64(dma_addr);
iod->npages = -1;
return (total_len - length) + PAGE_SIZE;
}
list[0] = prp_list;
iod->first_dma = prp_dma;
cmd->prp2 = cpu_to_le64(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;
}
struct nvme_bio_pair {
struct bio b1, b2, *parent;
struct bio_vec *bv1, *bv2;
int err;
atomic_t cnt;
};
static void nvme_bio_pair_endio(struct bio *bio, int err)
{
struct nvme_bio_pair *bp = bio->bi_private;
if (err)
bp->err = err;
if (atomic_dec_and_test(&bp->cnt)) {
bio_endio(bp->parent, bp->err);
kfree(bp->bv1);
kfree(bp->bv2);
kfree(bp);
}
}
static struct nvme_bio_pair *nvme_bio_split(struct bio *bio, int idx,
int len, int offset)
{
struct nvme_bio_pair *bp;
BUG_ON(len > bio->bi_iter.bi_size);
BUG_ON(idx > bio->bi_vcnt);
bp = kmalloc(sizeof(*bp), GFP_ATOMIC);
if (!bp)
return NULL;
bp->err = 0;
bp->b1 = *bio;
bp->b2 = *bio;
bp->b1.bi_iter.bi_size = len;
bp->b2.bi_iter.bi_size -= len;
bp->b1.bi_vcnt = idx;
bp->b2.bi_iter.bi_idx = idx;
bp->b2.bi_iter.bi_sector += len >> 9;
if (offset) {
bp->bv1 = kmalloc(bio->bi_max_vecs * sizeof(struct bio_vec),
GFP_ATOMIC);
if (!bp->bv1)
goto split_fail_1;
bp->bv2 = kmalloc(bio->bi_max_vecs * sizeof(struct bio_vec),
GFP_ATOMIC);
if (!bp->bv2)
goto split_fail_2;
memcpy(bp->bv1, bio->bi_io_vec,
bio->bi_max_vecs * sizeof(struct bio_vec));
memcpy(bp->bv2, bio->bi_io_vec,
bio->bi_max_vecs * sizeof(struct bio_vec));
bp->b1.bi_io_vec = bp->bv1;
bp->b2.bi_io_vec = bp->bv2;
bp->b2.bi_io_vec[idx].bv_offset += offset;
bp->b2.bi_io_vec[idx].bv_len -= offset;
bp->b1.bi_io_vec[idx].bv_len = offset;
bp->b1.bi_vcnt++;
} else
bp->bv1 = bp->bv2 = NULL;
bp->b1.bi_private = bp;
bp->b2.bi_private = bp;
bp->b1.bi_end_io = nvme_bio_pair_endio;
bp->b2.bi_end_io = nvme_bio_pair_endio;
bp->parent = bio;
atomic_set(&bp->cnt, 2);
return bp;
split_fail_2:
kfree(bp->bv1);
split_fail_1:
kfree(bp);
return NULL;
}
static int nvme_split_and_submit(struct bio *bio, struct nvme_queue *nvmeq,
int idx, int len, int offset)
{
struct nvme_bio_pair *bp = nvme_bio_split(bio, idx, len, offset);
if (!bp)
return -ENOMEM;
if (bio_list_empty(&nvmeq->sq_cong))
add_wait_queue(&nvmeq->sq_full, &nvmeq->sq_cong_wait);
bio_list_add(&nvmeq->sq_cong, &bp->b1);
bio_list_add(&nvmeq->sq_cong, &bp->b2);
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,
iter.bi_idx,
length, 0);
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, iter.bi_idx,
split_len,
split_len - length);
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;
}
/*
* 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.
*/
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_command *cmnd = &nvmeq->sq_cmds[nvmeq->sq_tail];
range = dma_pool_alloc(nvmeq->dev->prp_small_pool, GFP_ATOMIC,
&iod->first_dma);
if (!range)
return -ENOMEM;
iod_list(iod)[0] = (__le64 *)range;
iod->npages = 0;
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;
}
int nvme_submit_flush_data(struct nvme_queue *nvmeq, struct nvme_ns *ns)
{
int cmdid = alloc_cmdid(nvmeq, (void *)CMD_CTX_FLUSH,
special_completion, NVME_IO_TIMEOUT);
if (unlikely(cmdid < 0))
return cmdid;
return nvme_submit_flush(nvmeq, ns, cmdid);
}
/*
* 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_command *cmnd;
struct nvme_iod *iod;
enum dma_data_direction dma_dir;
int cmdid, length, result;
u16 control;
u32 dsmgmt;
int psegs = bio_phys_segments(ns->queue, bio);
if ((bio->bi_rw & REQ_FLUSH) && psegs) {
result = nvme_submit_flush_data(nvmeq, ns);
if (result)
return result;
}
result = -ENOMEM;
iod = nvme_alloc_iod(psegs, bio->bi_iter.bi_size, GFP_ATOMIC);
if (!iod)
goto nomem;
iod->private = bio;
result = -EBUSY;
cmdid = alloc_cmdid(nvmeq, iod, bio_completion, NVME_IO_TIMEOUT);
if (unlikely(cmdid < 0))
goto free_iod;
if (bio->bi_rw & REQ_DISCARD) {
result = nvme_submit_discard(nvmeq, ns, bio, iod, cmdid);
if (result)
goto free_cmdid;
return result;
}
if ((bio->bi_rw & REQ_FLUSH) && !psegs)
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));
if (bio_data_dir(bio)) {
cmnd->rw.opcode = nvme_cmd_write;
dma_dir = DMA_TO_DEVICE;
} else {
cmnd->rw.opcode = nvme_cmd_read;
dma_dir = DMA_FROM_DEVICE;
}
result = nvme_map_bio(nvmeq, iod, bio, dma_dir, psegs);
if (result <= 0)
goto free_cmdid;
length = result;
cmnd->rw.command_id = cmdid;
cmnd->rw.nsid = cpu_to_le32(ns->ns_id);
length = nvme_setup_prps(nvmeq->dev, &cmnd->common, iod, length,
GFP_ATOMIC);
cmnd->rw.slba = cpu_to_le64(nvme_block_nr(ns, bio->bi_iter.bi_sector));
cmnd->rw.length = cpu_to_le16((length >> ns->lba_shift) - 1);
cmnd->rw.control = cpu_to_le16(control);
cmnd->rw.dsmgmt = cpu_to_le32(dsmgmt);
nvme_start_io_acct(bio);
if (++nvmeq->sq_tail == nvmeq->q_depth)
nvmeq->sq_tail = 0;
writel(nvmeq->sq_tail, nvmeq->q_db);
return 0;
free_cmdid:
free_cmdid(nvmeq, cmdid, NULL);
free_iod:
nvme_free_iod(nvmeq->dev, iod);
nomem:
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->dev, 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 + (1 << 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) {
put_nvmeq(NULL);
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 (bio_list_empty(&nvmeq->sq_cong))
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_dev *dev, 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
*/
int nvme_submit_sync_cmd(struct nvme_queue *nvmeq, struct nvme_command *cmd,
u32 *result, unsigned timeout)
{
int cmdid;
struct sync_cmd_info cmdinfo;
cmdinfo.task = current;
cmdinfo.status = -EINTR;
cmdid = alloc_cmdid_killable(nvmeq, &cmdinfo, sync_completion,
timeout);
if (cmdid < 0)
return cmdid;
cmd->common.command_id = cmdid;
set_current_state(TASK_KILLABLE);
nvme_submit_cmd(nvmeq, cmd);
schedule_timeout(timeout);
if (cmdinfo.status == -EINTR) {
nvme_abort_command(nvmeq, cmdid);
return -EINTR;
}
if (result)
*result = cmdinfo.result;
return cmdinfo.status;
}
int nvme_submit_admin_cmd(struct nvme_dev *dev, struct nvme_command *cmd,
u32 *result)
{
return nvme_submit_sync_cmd(dev->queues[0], cmd, result, 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_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;
dev_warn(nvmeq->q_dmadev, "Cancelling I/O %d\n", cmdid);
ctx = cancel_cmdid(nvmeq, cmdid, &fn);
fn(nvmeq->dev, ctx, &cqe);
}
}
static void nvme_free_queue(struct nvme_queue *nvmeq)
{
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);
}
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);
kfree(nvmeq);
}
static void nvme_free_queues(struct nvme_dev *dev)
{
int i;
for (i = dev->queue_count - 1; i >= 0; i--) {
nvme_free_queue(dev->queues[i]);
dev->queue_count--;
dev->queues[i] = NULL;
}
}
static void nvme_disable_queue(struct nvme_dev *dev, int qid)
{
struct nvme_queue *nvmeq = dev->queues[qid];
int vector = dev->entry[nvmeq->cq_vector].vector;
spin_lock_irq(&nvmeq->q_lock);
if (nvmeq->q_suspended) {
spin_unlock_irq(&nvmeq->q_lock);
return;
}
nvmeq->q_suspended = 1;
spin_unlock_irq(&nvmeq->q_lock);
irq_set_affinity_hint(vector, NULL);
free_irq(vector, nvmeq);
/* Don't tell the adapter to delete the admin queue */
if (qid) {
adapter_delete_sq(dev, qid);
adapter_delete_cq(dev, qid);
}
spin_lock_irq(&nvmeq->q_lock);
nvme_process_cq(nvmeq);
nvme_cancel_ios(nvmeq, false);
spin_unlock_irq(&nvmeq->q_lock);
}
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;
nvmeq->q_dmadev = dmadev;
nvmeq->dev = dev;
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);
nvmeq->q_db = &dev->dbs[qid << (dev->db_stride + 1)];
nvmeq->q_depth = depth;
nvmeq->cq_vector = vector;
nvmeq->q_suspended = 1;
dev->queue_count++;
return nvmeq;
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_DISABLED | IRQF_SHARED,
name, nvmeq);
return request_irq(dev->entry[nvmeq->cq_vector].vector, nvme_irq,
IRQF_DISABLED | 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 << (dev->db_stride + 1)];
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;
}
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, "nvme");
if (result < 0)
goto release_sq;
spin_lock(&nvmeq->q_lock);
nvme_init_queue(nvmeq, qid);
spin_unlock(&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 initialisation\n");
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 = dev->queues[0];
if (!nvmeq) {
nvmeq = nvme_alloc_queue(dev, 0, 64, 0);
if (!nvmeq)
return -ENOMEM;
dev->queues[0] = nvmeq;
}
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, "nvme admin");
if (result)
return result;
spin_lock(&nvmeq->q_lock);
nvme_init_queue(nvmeq, 0);
spin_unlock(&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;
}
iod = nvme_alloc_iod(count, length, GFP_KERNEL);
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;
err = -ENOMEM;
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_queue *nvmeq;
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, &c.common, iod, length, GFP_KERNEL);
nvmeq = get_nvmeq(dev);
/*
* Since nvme_submit_sync_cmd sleeps, we can't keep preemption
* disabled. We may be preempted at any point, and be rescheduled
* to a different CPU. That will cause cacheline bouncing, but no
* additional races since q_lock already protects against other CPUs.
*/
put_nvmeq(nvmeq);
if (length != (io.nblocks + 1) << ns->lba_shift)
status = -ENOMEM;
else if (!nvmeq || nvmeq->q_suspended)
status = -EBUSY;
else
status = nvme_submit_sync_cmd(nvmeq, &c, NULL, NVME_IO_TIMEOUT);
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, &c.common, iod, length,
GFP_KERNEL);
}
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->queues[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;
}
}
static const struct block_device_operations nvme_fops = {
.owner = THIS_MODULE,
.ioctl = nvme_ioctl,
.compat_ioctl = nvme_ioctl,
};
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))
remove_wait_queue(&nvmeq->sq_full,
&nvmeq->sq_cong_wait);
if (nvme_submit_bio_queue(nvmeq, ns, bio)) {
if (bio_list_empty(&nvmeq->sq_cong))
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;
while (!kthread_should_stop()) {
set_current_state(TASK_INTERRUPTIBLE);
spin_lock(&dev_list_lock);
list_for_each_entry(dev, &dev_list, node) {
int i;
for (i = 0; i < dev->queue_count; i++) {
struct nvme_queue *nvmeq = 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);
unlock:
spin_unlock_irq(&nvmeq->q_lock);
}
}
spin_unlock(&dev_list_lock);
schedule_timeout(round_jiffies_relative(HZ));
}
return 0;
}
static DEFINE_IDA(nvme_index_ida);
static int nvme_get_ns_idx(void)
{
int index, error;
do {
if (!ida_pre_get(&nvme_index_ida, GFP_KERNEL))
return -1;
spin_lock(&dev_list_lock);
error = ida_get_new(&nvme_index_ida, &index);
spin_unlock(&dev_list_lock);
} while (error == -EAGAIN);
if (error)
index = -1;
return index;
}
static void nvme_put_ns_idx(int index)
{
spin_lock(&dev_list_lock);
ida_remove(&nvme_index_ida, index);
spin_unlock(&dev_list_lock);
}
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(NVME_MINORS);
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);
disk->major = nvme_major;
disk->minors = NVME_MINORS;
disk->first_minor = NVME_MINORS * nvme_get_ns_idx();
disk->fops = &nvme_fops;
disk->private_data = ns;
disk->queue = ns->queue;
disk->driverfs_dev = &dev->pci_dev->dev;
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 void nvme_ns_free(struct nvme_ns *ns)
{
int index = ns->disk->first_minor / NVME_MINORS;
put_disk(ns->disk);
nvme_put_ns_idx(index);
blk_cleanup_queue(ns->queue);
kfree(ns);
}
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)
return status < 0 ? -EIO : -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) << (dev->db_stride + 3));
}
static int nvme_setup_io_queues(struct nvme_dev *dev)
{
struct pci_dev *pdev = dev->pci_dev;
int result, cpu, i, vecs, nr_io_queues, size, q_depth;
nr_io_queues = num_online_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;
dev->queues[0]->q_db = dev->dbs;
}
/* Deregister the admin queue's interrupt */
free_irq(dev->entry[0].vector, dev->queues[0]);
vecs = nr_io_queues;
for (i = 0; i < vecs; i++)
dev->entry[i].entry = i;
for (;;) {
result = pci_enable_msix(pdev, dev->entry, vecs);
if (result <= 0)
break;
vecs = result;
}
if (result < 0) {
vecs = nr_io_queues;
if (vecs > 32)
vecs = 32;
for (;;) {
result = pci_enable_msi_block(pdev, vecs);
if (result == 0) {
for (i = 0; i < vecs; i++)
dev->entry[i].vector = i + pdev->irq;
break;
} else if (result < 0) {
vecs = 1;
break;
}
vecs = result;
}
}
/*
* 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;
result = queue_request_irq(dev, dev->queues[0], "nvme admin");
if (result) {
dev->queues[0]->q_suspended = 1;
goto free_queues;
}
/* Free previously allocated queues that are no longer usable */
spin_lock(&dev_list_lock);
for (i = dev->queue_count - 1; i > nr_io_queues; i--) {
struct nvme_queue *nvmeq = dev->queues[i];
spin_lock(&nvmeq->q_lock);
nvme_cancel_ios(nvmeq, false);
spin_unlock(&nvmeq->q_lock);
nvme_free_queue(nvmeq);
dev->queue_count--;
dev->queues[i] = NULL;
}
spin_unlock(&dev_list_lock);
cpu = cpumask_first(cpu_online_mask);
for (i = 0; i < nr_io_queues; i++) {
irq_set_affinity_hint(dev->entry[i].vector, get_cpu_mask(cpu));
cpu = cpumask_next(cpu, cpu_online_mask);
}
q_depth = min_t(int, NVME_CAP_MQES(readq(&dev->bar->cap)) + 1,
NVME_Q_DEPTH);
for (i = dev->queue_count - 1; i < nr_io_queues; i++) {
dev->queues[i + 1] = nvme_alloc_queue(dev, i + 1, q_depth, i);
if (!dev->queues[i + 1]) {
result = -ENOMEM;
goto free_queues;
}
}
for (; i < num_possible_cpus(); i++) {
int target = i % rounddown_pow_of_two(dev->queue_count - 1);
dev->queues[i + 1] = dev->queues[target + 1];
}
for (i = 1; i < dev->queue_count; i++) {
result = nvme_create_queue(dev->queues[i], i);
if (result) {
for (--i; i > 0; i--)
nvme_disable_queue(dev, i);
goto free_queues;
}
}
return 0;
free_queues:
nvme_free_queues(dev);
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)
{
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(&dev->pci_dev->dev, 8192, &dma_addr,
GFP_KERNEL);
if (!mem)
return -ENOMEM;
res = nvme_identify(dev, 0, 1, dma_addr);
if (res) {
res = -EIO;
goto out;
}
ctrl = mem;
nn = le32_to_cpup(&ctrl->nn);
dev->oncs = le16_to_cpup(&ctrl->oncs);
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 ((dev->pci_dev->vendor == PCI_VENDOR_ID_INTEL) &&
(dev->pci_dev->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)
{
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;
pci_set_drvdata(pdev, dev);
dev->bar = ioremap(pci_resource_start(pdev, 0), 8192);
if (!dev->bar)
goto disable;
dev->db_stride = NVME_CAP_STRIDE(readq(&dev->bar->cap));
dev->dbs = ((void __iomem *)dev->bar) + 4096;
return 0;
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);
}
static void nvme_dev_shutdown(struct nvme_dev *dev)
{
int i;
for (i = dev->queue_count - 1; i >= 0; i--)
nvme_disable_queue(dev, i);
spin_lock(&dev_list_lock);
list_del_init(&dev->node);
spin_unlock(&dev_list_lock);
if (dev->bar)
nvme_shutdown_ctrl(dev);
nvme_dev_unmap(dev);
}
static void nvme_dev_remove(struct nvme_dev *dev)
{
struct nvme_ns *ns, *next;
list_for_each_entry_safe(ns, next, &dev->namespaces, list) {
list_del(&ns->list);
del_gendisk(ns->disk);
nvme_ns_free(ns);
}
}
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_dev(struct kref *kref)
{
struct nvme_dev *dev = container_of(kref, struct nvme_dev, kref);
nvme_dev_remove(dev);
nvme_dev_shutdown(dev);
nvme_free_queues(dev);
nvme_release_instance(dev);
nvme_release_prp_pools(dev);
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;
result = nvme_dev_map(dev);
if (result)
return result;
result = nvme_configure_admin_queue(dev);
if (result)
goto unmap;
spin_lock(&dev_list_lock);
list_add(&dev->node, &dev_list);
spin_unlock(&dev_list_lock);
result = nvme_setup_io_queues(dev);
if (result && result != -EBUSY)
goto disable;
return result;
disable:
spin_lock(&dev_list_lock);
list_del_init(&dev->node);
spin_unlock(&dev_list_lock);
unmap:
nvme_dev_unmap(dev);
return result;
}
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;
INIT_LIST_HEAD(&dev->namespaces);
dev->pci_dev = pdev;
result = nvme_set_instance(dev);
if (result)
goto free;
result = nvme_setup_prp_pools(dev);
if (result)
goto release;
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;
kref_init(&dev->kref);
return 0;
remove:
nvme_dev_remove(dev);
shutdown:
nvme_dev_shutdown(dev);
release_pools:
nvme_free_queues(dev);
nvme_release_prp_pools(dev);
release:
nvme_release_instance(dev);
free:
kfree(dev->queues);
kfree(dev->entry);
kfree(dev);
return result;
}
static void nvme_remove(struct pci_dev *pdev)
{
struct nvme_dev *dev = pci_get_drvdata(pdev);
misc_deregister(&dev->miscdev);
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
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);
int ret;
ret = nvme_dev_start(ndev);
/* XXX: should remove gendisks if resume fails */
if (ret)
nvme_free_queues(ndev);
return ret;
}
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,
};
/* Move to pci_ids.h later */
#define PCI_CLASS_STORAGE_EXPRESS 0x010802
static DEFINE_PCI_DEVICE_TABLE(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,
.driver = {
.pm = &nvme_dev_pm_ops,
},
.err_handler = &nvme_err_handler,
};
static int __init nvme_init(void)
{
int result;
nvme_thread = kthread_run(nvme_kthread, NULL, "nvme");
if (IS_ERR(nvme_thread))
return PTR_ERR(nvme_thread);
result = register_blkdev(nvme_major, "nvme");
if (result < 0)
goto kill_kthread;
else if (result > 0)
nvme_major = result;
result = pci_register_driver(&nvme_driver);
if (result)
goto unregister_blkdev;
return 0;
unregister_blkdev:
unregister_blkdev(nvme_major, "nvme");
kill_kthread:
kthread_stop(nvme_thread);
return result;
}
static void __exit nvme_exit(void)
{
pci_unregister_driver(&nvme_driver);
unregister_blkdev(nvme_major, "nvme");
kthread_stop(nvme_thread);
}
MODULE_AUTHOR("Matthew Wilcox <willy@linux.intel.com>");
MODULE_LICENSE("GPL");
MODULE_VERSION("0.8");
module_init(nvme_init);
module_exit(nvme_exit);
Ссылка в новой задаче Показать git blame Копировать постоянную ссылку