linux/drivers/block/nvme.c

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/*
* 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/blkdev.h>
#include <linux/errno.h>
#include <linux/fs.h>
#include <linux/genhd.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/kdev_t.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/sched.h>
#include <linux/slab.h>
#include <linux/types.h>
#include <linux/version.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
static int nvme_major;
module_param(nvme_major, int, 0);
static int use_threaded_interrupts;
module_param(use_threaded_interrupts, int, 0);
/*
* Represents an NVM Express device. Each nvme_dev is a PCI function.
*/
struct nvme_dev {
struct nvme_queue **queues;
u32 __iomem *dbs;
struct pci_dev *pci_dev;
int instance;
int queue_count;
u32 ctrl_config;
struct msix_entry *entry;
struct nvme_bar __iomem *bar;
struct list_head namespaces;
char serial[20];
char model[40];
char firmware_rev[8];
};
/*
* An NVM Express namespace is equivalent to a SCSI LUN
*/
struct nvme_ns {
struct list_head list;
struct nvme_dev *dev;
struct request_queue *queue;
struct gendisk *disk;
int ns_id;
int lba_shift;
};
/*
* 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;
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;
struct bio_list sq_cong;
u32 __iomem *q_db;
u16 q_depth;
u16 cq_vector;
u16 sq_head;
u16 sq_tail;
u16 cq_head;
u16 cq_phase;
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_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);
}
/**
* alloc_cmdid - Allocate a Command ID
* @param nvmeq The queue that will be used for this command
* @param ctx A pointer that will be passed to the handler
* @param handler The ID of the handler to call
*
* 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.
*/
static int alloc_cmdid(struct nvme_queue *nvmeq, void *ctx, int handler)
{
int depth = nvmeq->q_depth;
unsigned long data = (unsigned long)ctx | handler;
int cmdid;
BUG_ON((unsigned long)ctx & 3);
do {
cmdid = find_first_zero_bit(nvmeq->cmdid_data, depth);
if (cmdid >= depth)
return -EBUSY;
} while (test_and_set_bit(cmdid, nvmeq->cmdid_data));
nvmeq->cmdid_data[cmdid + BITS_TO_LONGS(depth)] = data;
return cmdid;
}
static int alloc_cmdid_killable(struct nvme_queue *nvmeq, void *ctx,
int handler)
{
int cmdid;
wait_event_killable(nvmeq->sq_full,
(cmdid = alloc_cmdid(nvmeq, ctx, handler)) >= 0);
return (cmdid < 0) ? -EINTR : cmdid;
}
/* If you need more than four handlers, you'll need to change how
* alloc_cmdid and nvme_process_cq work. Consider using a special
* CMD_CTX value instead, if that works for your situation.
*/
enum {
sync_completion_id = 0,
bio_completion_id,
};
#define CMD_CTX_BASE (POISON_POINTER_DELTA + sync_completion_id)
#define CMD_CTX_CANCELLED (0x2008 + CMD_CTX_BASE)
#define CMD_CTX_COMPLETED (0x2010 + CMD_CTX_BASE)
#define CMD_CTX_INVALID (0x2014 + CMD_CTX_BASE)
static unsigned long free_cmdid(struct nvme_queue *nvmeq, int cmdid)
{
unsigned long data;
unsigned offset = cmdid + BITS_TO_LONGS(nvmeq->q_depth);
if (cmdid > nvmeq->q_depth)
return CMD_CTX_INVALID;
data = nvmeq->cmdid_data[offset];
nvmeq->cmdid_data[offset] = CMD_CTX_COMPLETED;
clear_bit(cmdid, nvmeq->cmdid_data);
wake_up(&nvmeq->sq_full);
return data;
}
static void cancel_cmdid_data(struct nvme_queue *nvmeq, int cmdid)
{
unsigned offset = cmdid + BITS_TO_LONGS(nvmeq->q_depth);
nvmeq->cmdid_data[offset] = CMD_CTX_CANCELLED;
}
static struct nvme_queue *get_nvmeq(struct nvme_ns *ns)
{
int qid, cpu = get_cpu();
if (cpu < ns->dev->queue_count)
qid = cpu + 1;
else
qid = (cpu % rounddown_pow_of_two(ns->dev->queue_count)) + 1;
return ns->dev->queues[qid];
}
static 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;
/* XXX: Need to check tail isn't going to overrun head */
spin_lock_irqsave(&nvmeq->q_lock, flags);
tail = nvmeq->sq_tail;
memcpy(&nvmeq->sq_cmds[tail], cmd, sizeof(*cmd));
writel(tail, nvmeq->q_db);
if (++tail == nvmeq->q_depth)
tail = 0;
nvmeq->sq_tail = tail;
spin_unlock_irqrestore(&nvmeq->q_lock, flags);
return 0;
}
struct nvme_req_info {
struct bio *bio;
int nents;
struct scatterlist sg[0];
};
/* XXX: use a mempool */
static struct nvme_req_info *alloc_info(unsigned nseg, gfp_t gfp)
{
return kmalloc(sizeof(struct nvme_req_info) +
sizeof(struct scatterlist) * nseg, gfp);
}
static void free_info(struct nvme_req_info *info)
{
kfree(info);
}
static void bio_completion(struct nvme_queue *nvmeq, void *ctx,
struct nvme_completion *cqe)
{
struct nvme_req_info *info = ctx;
struct bio *bio = info->bio;
u16 status = le16_to_cpup(&cqe->status) >> 1;
dma_unmap_sg(nvmeq->q_dmadev, info->sg, info->nents,
bio_data_dir(bio) ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
free_info(info);
bio_endio(bio, status ? -EIO : 0);
}
/* length is in bytes */
static void nvme_setup_prps(struct nvme_common_command *cmd,
struct scatterlist *sg, int length)
{
int dma_len = sg_dma_len(sg);
u64 dma_addr = sg_dma_address(sg);
int offset = offset_in_page(dma_addr);
cmd->prp1 = cpu_to_le64(dma_addr);
length -= (PAGE_SIZE - offset);
if (length <= 0)
return;
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;
}
/* XXX: support PRP lists */
}
static int nvme_map_bio(struct device *dev, struct nvme_req_info *info,
struct bio *bio, enum dma_data_direction dma_dir, int psegs)
{
struct bio_vec *bvec;
struct scatterlist *sg = info->sg;
int i, nsegs;
sg_init_table(sg, psegs);
bio_for_each_segment(bvec, bio, i) {
sg_set_page(sg, bvec->bv_page, bvec->bv_len, bvec->bv_offset);
/* XXX: handle non-mergable here */
nsegs++;
}
info->nents = nsegs;
return dma_map_sg(dev, info->sg, info->nents, dma_dir);
}
static int nvme_submit_bio_queue(struct nvme_queue *nvmeq, struct nvme_ns *ns,
struct bio *bio)
{
struct nvme_command *cmnd;
struct nvme_req_info *info;
enum dma_data_direction dma_dir;
int cmdid;
u16 control;
u32 dsmgmt;
unsigned long flags;
int psegs = bio_phys_segments(ns->queue, bio);
info = alloc_info(psegs, GFP_NOIO);
if (!info)
goto congestion;
info->bio = bio;
cmdid = alloc_cmdid(nvmeq, info, bio_completion_id);
if (unlikely(cmdid < 0))
goto free_info;
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;
spin_lock_irqsave(&nvmeq->q_lock, flags);
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;
}
nvme_map_bio(nvmeq->q_dmadev, info, bio, dma_dir, psegs);
cmnd->rw.flags = 1;
cmnd->rw.command_id = cmdid;
cmnd->rw.nsid = cpu_to_le32(ns->ns_id);
nvme_setup_prps(&cmnd->common, info->sg, bio->bi_size);
cmnd->rw.slba = cpu_to_le64(bio->bi_sector >> (ns->lba_shift - 9));
cmnd->rw.length = cpu_to_le16((bio->bi_size >> ns->lba_shift) - 1);
cmnd->rw.control = cpu_to_le16(control);
cmnd->rw.dsmgmt = cpu_to_le32(dsmgmt);
writel(nvmeq->sq_tail, nvmeq->q_db);
if (++nvmeq->sq_tail == nvmeq->q_depth)
nvmeq->sq_tail = 0;
spin_unlock_irqrestore(&nvmeq->q_lock, flags);
return 0;
free_info:
free_info(info);
congestion:
return -EBUSY;
}
/*
* NB: return value of non-zero would mean that we were a stacking driver.
* make_request must always succeed.
*/
static int nvme_make_request(struct request_queue *q, struct bio *bio)
{
struct nvme_ns *ns = q->queuedata;
struct nvme_queue *nvmeq = get_nvmeq(ns);
if (nvme_submit_bio_queue(nvmeq, ns, bio)) {
blk_set_queue_congested(q, rw_is_sync(bio->bi_rw));
bio_list_add(&nvmeq->sq_cong, bio);
}
put_nvmeq(nvmeq);
return 0;
}
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;
if ((unsigned long)cmdinfo == CMD_CTX_CANCELLED)
return;
if (unlikely((unsigned long)cmdinfo == 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 (unlikely((unsigned long)cmdinfo == 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;
}
cmdinfo->result = le32_to_cpup(&cqe->result);
cmdinfo->status = le16_to_cpup(&cqe->status) >> 1;
wake_up_process(cmdinfo->task);
}
typedef void (*completion_fn)(struct nvme_queue *, void *,
struct nvme_completion *);
static irqreturn_t nvme_process_cq(struct nvme_queue *nvmeq)
{
u16 head, phase;
static const completion_fn completions[4] = {
[sync_completion_id] = sync_completion,
[bio_completion_id] = bio_completion,
};
head = nvmeq->cq_head;
phase = nvmeq->cq_phase;
for (;;) {
unsigned long data;
void *ptr;
unsigned char handler;
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;
}
data = free_cmdid(nvmeq, cqe.command_id);
handler = data & 3;
ptr = (void *)(data & ~3UL);
completions[handler](nvmeq, ptr, &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 IRQ_NONE;
writel(head, nvmeq->q_db + 1);
nvmeq->cq_head = head;
nvmeq->cq_phase = phase;
return IRQ_HANDLED;
}
static irqreturn_t nvme_irq(int irq, void *data)
{
return nvme_process_cq(data);
}
static irqreturn_t nvme_irq_thread(int irq, void *data)
{
irqreturn_t result;
struct nvme_queue *nvmeq = data;
spin_lock(&nvmeq->q_lock);
result = nvme_process_cq(nvmeq);
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_data(nvmeq, cmdid);
spin_unlock_irq(&nvmeq->q_lock);
}
/*
* 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_queue *nvmeq,
struct nvme_command *cmd, u32 *result)
{
int cmdid;
struct sync_cmd_info cmdinfo;
cmdinfo.task = current;
cmdinfo.status = -EINTR;
cmdid = alloc_cmdid_killable(nvmeq, &cmdinfo, sync_completion_id);
if (cmdid < 0)
return cmdid;
cmd->common.command_id = cmdid;
set_current_state(TASK_KILLABLE);
nvme_submit_cmd(nvmeq, cmd);
schedule();
if (cmdinfo.status == -EINTR) {
nvme_abort_command(nvmeq, cmdid);
return -EINTR;
}
if (result)
*result = cmdinfo.result;
return cmdinfo.status;
}
static 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);
}
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);
}
static void nvme_free_queue(struct nvme_dev *dev, int qid)
{
struct nvme_queue *nvmeq = dev->queues[qid];
free_irq(dev->entry[nvmeq->cq_vector].vector, nvmeq);
/* Don't tell the adapter to delete the admin queue */
if (qid) {
adapter_delete_sq(dev, qid);
adapter_delete_cq(dev, qid);
}
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 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 = (depth + BITS_TO_LONGS(depth)) * sizeof(long);
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;
spin_lock_init(&nvmeq->q_lock);
nvmeq->cq_head = 0;
nvmeq->cq_phase = 1;
init_waitqueue_head(&nvmeq->sq_full);
bio_list_init(&nvmeq->sq_cong);
nvmeq->q_db = &dev->dbs[qid * 2];
nvmeq->q_depth = depth;
nvmeq->cq_vector = vector;
return nvmeq;
free_cqdma:
dma_free_coherent(dmadev, CQ_SIZE(nvmeq->q_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_thread,
IRQF_DISABLED | IRQF_SHARED,
name, nvmeq);
return request_irq(dev->entry[nvmeq->cq_vector].vector, nvme_irq,
IRQF_DISABLED | IRQF_SHARED, name, nvmeq);
}
static __devinit struct nvme_queue *nvme_create_queue(struct nvme_dev *dev,
int qid, int cq_size, int vector)
{
int result;
struct nvme_queue *nvmeq = nvme_alloc_queue(dev, qid, cq_size, vector);
if (!nvmeq)
return NULL;
result = adapter_alloc_cq(dev, qid, nvmeq);
if (result < 0)
goto free_nvmeq;
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;
return nvmeq;
release_sq:
adapter_delete_sq(dev, qid);
release_cq:
adapter_delete_cq(dev, qid);
free_nvmeq:
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);
return NULL;
}
static int __devinit nvme_configure_admin_queue(struct nvme_dev *dev)
{
int result;
u32 aqa;
struct nvme_queue *nvmeq;
dev->dbs = ((void __iomem *)dev->bar) + 4096;
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;
writel(0, &dev->bar->cc);
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);
while (!(readl(&dev->bar->csts) & NVME_CSTS_RDY)) {
msleep(100);
if (fatal_signal_pending(current))
return -EINTR;
}
result = queue_request_irq(dev, nvmeq, "nvme admin");
dev->queues[0] = nvmeq;
return result;
}
static int nvme_map_user_pages(struct nvme_dev *dev, int write,
unsigned long addr, unsigned length,
struct scatterlist **sgp)
{
int i, err, count, nents, offset;
struct scatterlist *sg;
struct page **pages;
if (addr & 3)
return -EINVAL;
if (!length)
return -EINVAL;
offset = offset_in_page(addr);
count = DIV_ROUND_UP(offset + length, PAGE_SIZE);
pages = kcalloc(count, sizeof(*pages), GFP_KERNEL);
err = get_user_pages_fast(addr, count, 1, pages);
if (err < count) {
count = err;
err = -EFAULT;
goto put_pages;
}
sg = kcalloc(count, sizeof(*sg), GFP_KERNEL);
sg_init_table(sg, count);
sg_set_page(&sg[0], pages[0], PAGE_SIZE - offset, offset);
length -= (PAGE_SIZE - offset);
for (i = 1; i < count; i++) {
sg_set_page(&sg[i], pages[i], min_t(int, length, PAGE_SIZE), 0);
length -= PAGE_SIZE;
}
err = -ENOMEM;
nents = dma_map_sg(&dev->pci_dev->dev, sg, count,
write ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
if (!nents)
goto put_pages;
kfree(pages);
*sgp = sg;
return nents;
put_pages:
for (i = 0; i < count; i++)
put_page(pages[i]);
kfree(pages);
return err;
}
static void nvme_unmap_user_pages(struct nvme_dev *dev, int write,
unsigned long addr, int length,
struct scatterlist *sg, int nents)
{
int i, count;
count = DIV_ROUND_UP(offset_in_page(addr) + length, PAGE_SIZE);
dma_unmap_sg(&dev->pci_dev->dev, sg, nents, DMA_FROM_DEVICE);
for (i = 0; i < count; i++)
put_page(sg_page(&sg[i]));
}
static int nvme_submit_user_admin_command(struct nvme_dev *dev,
unsigned long addr, unsigned length,
struct nvme_command *cmd)
{
int err, nents;
struct scatterlist *sg;
nents = nvme_map_user_pages(dev, 0, addr, length, &sg);
if (nents < 0)
return nents;
nvme_setup_prps(&cmd->common, sg, length);
err = nvme_submit_admin_cmd(dev, cmd, NULL);
nvme_unmap_user_pages(dev, 0, addr, length, sg, nents);
return err ? -EIO : 0;
}
static int nvme_identify(struct nvme_ns *ns, unsigned long addr, int cns)
{
struct nvme_command c;
memset(&c, 0, sizeof(c));
c.identify.opcode = nvme_admin_identify;
c.identify.nsid = cns ? 0 : cpu_to_le32(ns->ns_id);
c.identify.cns = cpu_to_le32(cns);
return nvme_submit_user_admin_command(ns->dev, addr, 4096, &c);
}
static int nvme_get_range_type(struct nvme_ns *ns, unsigned long addr)
{
struct nvme_command c;
memset(&c, 0, sizeof(c));
c.features.opcode = nvme_admin_get_features;
c.features.nsid = cpu_to_le32(ns->ns_id);
c.features.fid = cpu_to_le32(NVME_FEAT_LBA_RANGE);
return nvme_submit_user_admin_command(ns->dev, addr, 4096, &c);
}
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;
u32 result;
int nents, status;
struct scatterlist *sg;
if (copy_from_user(&io, uio, sizeof(io)))
return -EFAULT;
length = io.nblocks << io.block_shift;
nents = nvme_map_user_pages(dev, io.opcode & 1, io.addr, length, &sg);
if (nents < 0)
return nents;
memset(&c, 0, sizeof(c));
c.rw.opcode = io.opcode;
c.rw.flags = io.flags;
c.rw.nsid = cpu_to_le32(io.nsid);
c.rw.slba = cpu_to_le64(io.slba);
c.rw.length = cpu_to_le16(io.nblocks - 1);
c.rw.control = cpu_to_le16(io.control);
c.rw.dsmgmt = cpu_to_le16(io.dsmgmt);
c.rw.reftag = cpu_to_le32(io.reftag); /* XXX: endian? */
c.rw.apptag = cpu_to_le16(io.apptag);
c.rw.appmask = cpu_to_le16(io.appmask);
/* XXX: metadata */
nvme_setup_prps(&c.common, sg, length);
nvmeq = get_nvmeq(ns);
/* 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);
status = nvme_submit_sync_cmd(nvmeq, &c, &result);
nvme_unmap_user_pages(dev, io.opcode & 1, io.addr, length, sg, nents);
put_user(result, &uio->result);
return status;
}
static int nvme_download_firmware(struct nvme_ns *ns,
struct nvme_dlfw __user *udlfw)
{
struct nvme_dev *dev = ns->dev;
struct nvme_dlfw dlfw;
struct nvme_command c;
int nents, status;
struct scatterlist *sg;
if (copy_from_user(&dlfw, udlfw, sizeof(dlfw)))
return -EFAULT;
if (dlfw.length >= (1 << 30))
return -EINVAL;
nents = nvme_map_user_pages(dev, 1, dlfw.addr, dlfw.length * 4, &sg);
if (nents < 0)
return nents;
memset(&c, 0, sizeof(c));
c.dlfw.opcode = nvme_admin_download_fw;
c.dlfw.numd = cpu_to_le32(dlfw.length);
c.dlfw.offset = cpu_to_le32(dlfw.offset);
nvme_setup_prps(&c.common, sg, dlfw.length * 4);
status = nvme_submit_admin_cmd(dev, &c, NULL);
nvme_unmap_user_pages(dev, 0, dlfw.addr, dlfw.length * 4, sg, nents);
return status;
}
static int nvme_activate_firmware(struct nvme_ns *ns, unsigned long arg)
{
struct nvme_dev *dev = ns->dev;
struct nvme_command c;
memset(&c, 0, sizeof(c));
c.common.opcode = nvme_admin_activate_fw;
c.common.rsvd10[0] = cpu_to_le32(arg);
return nvme_submit_admin_cmd(dev, &c, NULL);
}
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_IDENTIFY_NS:
return nvme_identify(ns, arg, 0);
case NVME_IOCTL_IDENTIFY_CTRL:
return nvme_identify(ns, arg, 1);
case NVME_IOCTL_GET_RANGE_TYPE:
return nvme_get_range_type(ns, arg);
case NVME_IOCTL_SUBMIT_IO:
return nvme_submit_io(ns, (void __user *)arg);
case NVME_IOCTL_DOWNLOAD_FW:
return nvme_download_firmware(ns, (void __user *)arg);
case NVME_IOCTL_ACTIVATE_FW:
return nvme_activate_firmware(ns, arg);
default:
return -ENOTTY;
}
}
static const struct block_device_operations nvme_fops = {
.owner = THIS_MODULE,
.ioctl = nvme_ioctl,
};
static struct nvme_ns *nvme_alloc_ns(struct nvme_dev *dev, int index,
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_NOMERGES |
QUEUE_FLAG_NONROT | QUEUE_FLAG_DISCARD;
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 = index;
ns->disk = disk;
lbaf = id->flbas & 0xf;
ns->lba_shift = id->lbaf[lbaf].ds;
disk->major = nvme_major;
disk->minors = NVME_MINORS;
disk->first_minor = NVME_MINORS * index;
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, index);
set_capacity(disk, le64_to_cpup(&id->nsze) << (ns->lba_shift - 9));
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)
{
put_disk(ns->disk);
blk_cleanup_queue(ns->queue);
kfree(ns);
}
static int set_queue_count(struct nvme_dev *dev, int count)
{
int status;
u32 result;
struct nvme_command c;
u32 q_count = (count - 1) | ((count - 1) << 16);
memset(&c, 0, sizeof(c));
c.features.opcode = nvme_admin_get_features;
c.features.fid = cpu_to_le32(NVME_FEAT_NUM_QUEUES);
c.features.dword11 = cpu_to_le32(q_count);
status = nvme_submit_admin_cmd(dev, &c, &result);
if (status)
return -EIO;
return min(result & 0xffff, result >> 16) + 1;
}
static int __devinit nvme_setup_io_queues(struct nvme_dev *dev)
{
int result, cpu, i, nr_queues;
nr_queues = num_online_cpus();
result = set_queue_count(dev, nr_queues);
if (result < 0)
return result;
if (result < nr_queues)
nr_queues = result;
/* Deregister the admin queue's interrupt */
free_irq(dev->entry[0].vector, dev->queues[0]);
for (i = 0; i < nr_queues; i++)
dev->entry[i].entry = i;
for (;;) {
result = pci_enable_msix(dev->pci_dev, dev->entry, nr_queues);
if (result == 0) {
break;
} else if (result > 0) {
nr_queues = result;
continue;
} else {
nr_queues = 1;
break;
}
}
result = queue_request_irq(dev, dev->queues[0], "nvme admin");
/* XXX: handle failure here */
cpu = cpumask_first(cpu_online_mask);
for (i = 0; i < nr_queues; i++) {
irq_set_affinity_hint(dev->entry[i].vector, get_cpu_mask(cpu));
cpu = cpumask_next(cpu, cpu_online_mask);
}
for (i = 0; i < nr_queues; i++) {
dev->queues[i + 1] = nvme_create_queue(dev, i + 1,
NVME_Q_DEPTH, i);
if (!dev->queues[i + 1])
return -ENOMEM;
dev->queue_count++;
}
return 0;
}
static void nvme_free_queues(struct nvme_dev *dev)
{
int i;
for (i = dev->queue_count - 1; i >= 0; i--)
nvme_free_queue(dev, i);
}
static int __devinit nvme_dev_add(struct nvme_dev *dev)
{
int res, nn, i;
struct nvme_ns *ns, *next;
struct nvme_id_ctrl *ctrl;
void *id;
dma_addr_t dma_addr;
struct nvme_command cid, crt;
res = nvme_setup_io_queues(dev);
if (res)
return res;
/* XXX: Switch to a SG list once prp2 works */
id = dma_alloc_coherent(&dev->pci_dev->dev, 8192, &dma_addr,
GFP_KERNEL);
memset(&cid, 0, sizeof(cid));
cid.identify.opcode = nvme_admin_identify;
cid.identify.nsid = 0;
cid.identify.prp1 = cpu_to_le64(dma_addr);
cid.identify.cns = cpu_to_le32(1);
res = nvme_submit_admin_cmd(dev, &cid, NULL);
if (res) {
res = -EIO;
goto out_free;
}
ctrl = id;
nn = le32_to_cpup(&ctrl->nn);
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));
cid.identify.cns = 0;
memset(&crt, 0, sizeof(crt));
crt.features.opcode = nvme_admin_get_features;
crt.features.prp1 = cpu_to_le64(dma_addr + 4096);
crt.features.fid = cpu_to_le32(NVME_FEAT_LBA_RANGE);
for (i = 0; i < nn; i++) {
cid.identify.nsid = cpu_to_le32(i);
res = nvme_submit_admin_cmd(dev, &cid, NULL);
if (res)
continue;
if (((struct nvme_id_ns *)id)->ncap == 0)
continue;
crt.features.nsid = cpu_to_le32(i);
res = nvme_submit_admin_cmd(dev, &crt, NULL);
if (res)
continue;
ns = nvme_alloc_ns(dev, i, id, id + 4096);
if (ns)
list_add_tail(&ns->list, &dev->namespaces);
}
list_for_each_entry(ns, &dev->namespaces, list)
add_disk(ns->disk);
dma_free_coherent(&dev->pci_dev->dev, 4096, id, dma_addr);
return 0;
out_free:
list_for_each_entry_safe(ns, next, &dev->namespaces, list) {
list_del(&ns->list);
nvme_ns_free(ns);
}
dma_free_coherent(&dev->pci_dev->dev, 4096, id, dma_addr);
return res;
}
static int nvme_dev_remove(struct nvme_dev *dev)
{
struct nvme_ns *ns, *next;
/* TODO: wait all I/O finished or cancel them */
list_for_each_entry_safe(ns, next, &dev->namespaces, list) {
list_del(&ns->list);
del_gendisk(ns->disk);
nvme_ns_free(ns);
}
nvme_free_queues(dev);
return 0;
}
/* XXX: Use an ida or something to let remove / add work correctly */
static void nvme_set_instance(struct nvme_dev *dev)
{
static int instance;
dev->instance = instance++;
}
static void nvme_release_instance(struct nvme_dev *dev)
{
}
static int __devinit nvme_probe(struct pci_dev *pdev,
const struct pci_device_id *id)
{
int bars, 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;
if (pci_enable_device_mem(pdev))
goto free;
pci_set_master(pdev);
bars = pci_select_bars(pdev, IORESOURCE_MEM);
if (pci_request_selected_regions(pdev, bars, "nvme"))
goto disable;
INIT_LIST_HEAD(&dev->namespaces);
dev->pci_dev = pdev;
pci_set_drvdata(pdev, dev);
dma_set_mask(&pdev->dev, DMA_BIT_MASK(64));
dma_set_coherent_mask(&pdev->dev, DMA_BIT_MASK(64));
nvme_set_instance(dev);
dev->entry[0].vector = pdev->irq;
dev->bar = ioremap(pci_resource_start(pdev, 0), 8192);
if (!dev->bar) {
result = -ENOMEM;
goto disable_msix;
}
result = nvme_configure_admin_queue(dev);
if (result)
goto unmap;
dev->queue_count++;
result = nvme_dev_add(dev);
if (result)
goto delete;
return 0;
delete:
nvme_free_queues(dev);
unmap:
iounmap(dev->bar);
disable_msix:
pci_disable_msix(pdev);
nvme_release_instance(dev);
disable:
pci_disable_device(pdev);
pci_release_regions(pdev);
free:
kfree(dev->queues);
kfree(dev->entry);
kfree(dev);
return result;
}
static void __devexit nvme_remove(struct pci_dev *pdev)
{
struct nvme_dev *dev = pci_get_drvdata(pdev);
nvme_dev_remove(dev);
pci_disable_msix(pdev);
iounmap(dev->bar);
nvme_release_instance(dev);
pci_disable_device(pdev);
pci_release_regions(pdev);
kfree(dev->queues);
kfree(dev->entry);
kfree(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
#define nvme_suspend NULL
#define nvme_resume NULL
static 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 = __devexit_p(nvme_remove),
.suspend = nvme_suspend,
.resume = nvme_resume,
.err_handler = &nvme_err_handler,
};
static int __init nvme_init(void)
{
int result;
nvme_major = register_blkdev(nvme_major, "nvme");
if (nvme_major <= 0)
return -EBUSY;
result = pci_register_driver(&nvme_driver);
if (!result)
return 0;
unregister_blkdev(nvme_major, "nvme");
return result;
}
static void __exit nvme_exit(void)
{
pci_unregister_driver(&nvme_driver);
unregister_blkdev(nvme_major, "nvme");
}
MODULE_AUTHOR("Matthew Wilcox <willy@linux.intel.com>");
MODULE_LICENSE("GPL");
MODULE_VERSION("0.2");
module_init(nvme_init);
module_exit(nvme_exit);