drivers/block/nvme.c

   1 /*
   2  * NVM Express device driver
   3  * Copyright (c) 2011, Intel Corporation.
   4  *
   5  * This program is free software; you can redistribute it and/or modify it
   6  * under the terms and conditions of the GNU General Public License,
   7  * version 2, as published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  12  * more details.
  13  *
  14  * You should have received a copy of the GNU General Public License along with
  15  * this program; if not, write to the Free Software Foundation, Inc.,
  16  * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
  17  */
  18
  19 #include <linux/nvme.h>
  20 #include <linux/bio.h>
  21 #include <linux/blkdev.h>
  22 #include <linux/errno.h>
  23 #include <linux/fs.h>
  24 #include <linux/genhd.h>
  25 #include <linux/init.h>
  26 #include <linux/interrupt.h>
  27 #include <linux/io.h>
  28 #include <linux/kdev_t.h>
  29 #include <linux/kernel.h>
  30 #include <linux/mm.h>
  31 #include <linux/module.h>
  32 #include <linux/moduleparam.h>
  33 #include <linux/pci.h>
  34 #include <linux/sched.h>
  35 #include <linux/slab.h>
  36 #include <linux/types.h>
  37 #include <linux/version.h>
  38
  39 #define NVME_Q_DEPTH 1024
  40 #define SQ_SIZE(depth)          (depth * sizeof(struct nvme_command))
  41 #define CQ_SIZE(depth)          (depth * sizeof(struct nvme_completion))
  42 #define NVME_MINORS 64
  43
  44 static int nvme_major;
  45 module_param(nvme_major, int, 0);
  46
  47 /*
  48  * Represents an NVM Express device.  Each nvme_dev is a PCI function.
  49  */
  50 struct nvme_dev {
  51         struct list_head node;
  52         struct nvme_queue **queues;
  53         u32 __iomem *dbs;
  54         struct pci_dev *pci_dev;
  55         int instance;
  56         int queue_count;
  57         u32 ctrl_config;
  58         struct msix_entry *entry;
  59         struct nvme_bar __iomem *bar;
  60         struct list_head namespaces;
  61 };
  62
  63 /*
  64  * An NVM Express namespace is equivalent to a SCSI LUN
  65  */
  66 struct nvme_ns {
  67         struct list_head list;
  68
  69         struct nvme_dev *dev;
  70         struct request_queue *queue;
  71         struct gendisk *disk;
  72
  73         int ns_id;
  74         int lba_shift;
  75 };
  76
  77 /*
  78  * An NVM Express queue.  Each device has at least two (one for admin
  79  * commands and one for I/O commands).
  80  */
  81 struct nvme_queue {
  82         struct device *q_dmadev;
  83         spinlock_t q_lock;
  84         struct nvme_command *sq_cmds;
  85         volatile struct nvme_completion *cqes;
  86         dma_addr_t sq_dma_addr;
  87         dma_addr_t cq_dma_addr;
  88         wait_queue_head_t sq_full;
  89         struct bio_list sq_cong;
  90         u32 __iomem *q_db;
  91         u16 q_depth;
  92         u16 cq_vector;
  93         u16 sq_head;
  94         u16 sq_tail;
  95         u16 cq_head;
  96         u16 cq_cycle;
  97         unsigned long cmdid_data[];
  98 };
  99
 100 /*
 101  * Check we didin't inadvertently grow the command struct
 102  */
 103 static inline void _nvme_check_size(void)
 104 {
 105         BUILD_BUG_ON(sizeof(struct nvme_rw_command) != 64);
 106         BUILD_BUG_ON(sizeof(struct nvme_create_cq) != 64);
 107         BUILD_BUG_ON(sizeof(struct nvme_create_sq) != 64);
 108         BUILD_BUG_ON(sizeof(struct nvme_delete_queue) != 64);
 109         BUILD_BUG_ON(sizeof(struct nvme_features) != 64);
 110         BUILD_BUG_ON(sizeof(struct nvme_command) != 64);
 111         BUILD_BUG_ON(sizeof(struct nvme_id_ctrl) != 4096);
 112         BUILD_BUG_ON(sizeof(struct nvme_id_ns) != 4096);
 113         BUILD_BUG_ON(sizeof(struct nvme_lba_range_type) != 64);
 114 }
 115
 116 /**
 117  * alloc_cmdid - Allocate a Command ID
 118  * @param nvmeq The queue that will be used for this command
 119  * @param ctx A pointer that will be passed to the handler
 120  * @param handler The ID of the handler to call
 121  *
 122  * Allocate a Command ID for a queue.  The data passed in will
 123  * be passed to the completion handler.  This is implemented by using
 124  * the bottom two bits of the ctx pointer to store the handler ID.
 125  * Passing in a pointer that's not 4-byte aligned will cause a BUG.
 126  * We can change this if it becomes a problem.
 127  */
 128 static int alloc_cmdid(struct nvme_queue *nvmeq, void *ctx, int handler)
 129 {
 130         int depth = nvmeq->q_depth;
 131         unsigned long data = (unsigned long)ctx | handler;
 132         int cmdid;
 133
 134         BUG_ON((unsigned long)ctx & 3);
 135
 136         do {
 137                 cmdid = find_first_zero_bit(nvmeq->cmdid_data, depth);
 138                 if (cmdid >= depth)
 139                         return -EBUSY;
 140         } while (test_and_set_bit(cmdid, nvmeq->cmdid_data));
 141
 142         nvmeq->cmdid_data[cmdid + BITS_TO_LONGS(depth)] = data;
 143         return cmdid;
 144 }
 145
 146 static int alloc_cmdid_killable(struct nvme_queue *nvmeq, void *ctx,
 147                                                                 int handler)
 148 {
 149         int cmdid;
 150         wait_event_killable(nvmeq->sq_full,
 151                         (cmdid = alloc_cmdid(nvmeq, ctx, handler)) >= 0);
 152         return (cmdid < 0) ? -EINTR : cmdid;
 153 }
 154
 155 /* If you need more than four handlers, you'll need to change how
 156  * alloc_cmdid and nvme_process_cq work
 157  */
 158 enum {
 159         sync_completion_id = 0,
 160         bio_completion_id,
 161 };
 162
 163 static unsigned long free_cmdid(struct nvme_queue *nvmeq, int cmdid)
 164 {
 165         unsigned long data;
 166
 167         data = nvmeq->cmdid_data[cmdid + BITS_TO_LONGS(nvmeq->q_depth)];
 168         clear_bit(cmdid, nvmeq->cmdid_data);
 169         wake_up(&nvmeq->sq_full);
 170         return data;
 171 }
 172
 173 static struct nvme_queue *get_nvmeq(struct nvme_ns *ns)
 174 {
 175         return ns->dev->queues[1];
 176 }
 177
 178 static void put_nvmeq(struct nvme_queue *nvmeq)
 179 {
 180 }
 181
 182 /**
 183  * nvme_submit_cmd: Copy a command into a queue and ring the doorbell
 184  * @nvmeq: The queue to use
 185  * @cmd: The command to send
 186  *
 187  * Safe to use from interrupt context
 188  */
 189 static int nvme_submit_cmd(struct nvme_queue *nvmeq, struct nvme_command *cmd)
 190 {
 191         unsigned long flags;
 192         u16 tail;
 193         /* XXX: Need to check tail isn't going to overrun head */
 194         spin_lock_irqsave(&nvmeq->q_lock, flags);
 195         tail = nvmeq->sq_tail;
 196         memcpy(&nvmeq->sq_cmds[tail], cmd, sizeof(*cmd));
 197         writel(tail, nvmeq->q_db);
 198         if (++tail == nvmeq->q_depth)
 199                 tail = 0;
 200         nvmeq->sq_tail = tail;
 201         spin_unlock_irqrestore(&nvmeq->q_lock, flags);
 202
 203         return 0;
 204 }
 205
 206 struct nvme_req_info {
 207         struct bio *bio;
 208         int nents;
 209         struct scatterlist sg[0];
 210 };
 211
 212 /* XXX: use a mempool */
 213 static struct nvme_req_info *alloc_info(unsigned nseg, gfp_t gfp)
 214 {
 215         return kmalloc(sizeof(struct nvme_req_info) +
 216                         sizeof(struct scatterlist) * nseg, gfp);
 217 }
 218
 219 static void free_info(struct nvme_req_info *info)
 220 {
 221         kfree(info);
 222 }
 223
 224 static void bio_completion(struct nvme_queue *nvmeq, void *ctx,
 225                                                 struct nvme_completion *cqe)
 226 {
 227         struct nvme_req_info *info = ctx;
 228         struct bio *bio = info->bio;
 229         u16 status = le16_to_cpup(&cqe->status) >> 1;
 230
 231         dma_unmap_sg(nvmeq->q_dmadev, info->sg, info->nents,
 232                         bio_data_dir(bio) ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
 233         free_info(info);
 234         bio_endio(bio, status ? -EIO : 0);
 235 }
 236
 237 static int nvme_map_bio(struct device *dev, struct nvme_req_info *info,
 238                 struct bio *bio, enum dma_data_direction dma_dir, int psegs)
 239 {
 240         struct bio_vec *bvec;
 241         struct scatterlist *sg = info->sg;
 242         int i, nsegs;
 243
 244         sg_init_table(sg, psegs);
 245         bio_for_each_segment(bvec, bio, i) {
 246                 sg_set_page(sg, bvec->bv_page, bvec->bv_len, bvec->bv_offset);
 247                 /* XXX: handle non-mergable here */
 248                 nsegs++;
 249         }
 250         info->nents = nsegs;
 251
 252         return dma_map_sg(dev, info->sg, info->nents, dma_dir);
 253 }
 254
 255 static int nvme_submit_bio_queue(struct nvme_queue *nvmeq, struct nvme_ns *ns,
 256                                                                 struct bio *bio)
 257 {
 258         struct nvme_rw_command *cmnd;
 259         struct nvme_req_info *info;
 260         enum dma_data_direction dma_dir;
 261         int cmdid;
 262         u16 control;
 263         u32 dsmgmt;
 264         unsigned long flags;
 265         int psegs = bio_phys_segments(ns->queue, bio);
 266
 267         info = alloc_info(psegs, GFP_NOIO);
 268         if (!info)
 269                 goto congestion;
 270         info->bio = bio;
 271
 272         cmdid = alloc_cmdid(nvmeq, info, bio_completion_id);
 273         if (unlikely(cmdid < 0))
 274                 goto free_info;
 275
 276         control = 0;
 277         if (bio->bi_rw & REQ_FUA)
 278                 control |= NVME_RW_FUA;
 279         if (bio->bi_rw & (REQ_FAILFAST_DEV | REQ_RAHEAD))
 280                 control |= NVME_RW_LR;
 281
 282         dsmgmt = 0;
 283         if (bio->bi_rw & REQ_RAHEAD)
 284                 dsmgmt |= NVME_RW_DSM_FREQ_PREFETCH;
 285
 286         spin_lock_irqsave(&nvmeq->q_lock, flags);
 287         cmnd = &nvmeq->sq_cmds[nvmeq->sq_tail].rw;
 288
 289         if (bio_data_dir(bio)) {
 290                 cmnd->opcode = nvme_cmd_write;
 291                 dma_dir = DMA_TO_DEVICE;
 292         } else {
 293                 cmnd->opcode = nvme_cmd_read;
 294                 dma_dir = DMA_FROM_DEVICE;
 295         }
 296
 297         nvme_map_bio(nvmeq->q_dmadev, info, bio, dma_dir, psegs);
 298
 299         cmnd->flags = 1;
 300         cmnd->command_id = cmdid;
 301         cmnd->nsid = cpu_to_le32(ns->ns_id);
 302         cmnd->prp1 = cpu_to_le64(sg_phys(info->sg));
 303         /* XXX: Support more than one PRP */
 304         cmnd->slba = cpu_to_le64(bio->bi_sector >> (ns->lba_shift - 9));
 305         cmnd->length = cpu_to_le16((bio->bi_size >> ns->lba_shift) - 1);
 306         cmnd->control = cpu_to_le16(control);
 307         cmnd->dsmgmt = cpu_to_le32(dsmgmt);
 308
 309         writel(nvmeq->sq_tail, nvmeq->q_db);
 310         if (++nvmeq->sq_tail == nvmeq->q_depth)
 311                 nvmeq->sq_tail = 0;
 312
 313         spin_unlock_irqrestore(&nvmeq->q_lock, flags);
 314
 315         return 0;
 316
 317  free_info:
 318         free_info(info);
 319  congestion:
 320         return -EBUSY;
 321 }
 322
 323 /*
 324  * NB: return value of non-zero would mean that we were a stacking driver.
 325  * make_request must always succeed.
 326  */
 327 static int nvme_make_request(struct request_queue *q, struct bio *bio)
 328 {
 329         struct nvme_ns *ns = q->queuedata;
 330         struct nvme_queue *nvmeq = get_nvmeq(ns);
 331
 332         if (nvme_submit_bio_queue(nvmeq, ns, bio)) {
 333                 blk_set_queue_congested(q, rw_is_sync(bio->bi_rw));
 334                 bio_list_add(&nvmeq->sq_cong, bio);
 335         }
 336         put_nvmeq(nvmeq);
 337
 338         return 0;
 339 }
 340
 341 struct sync_cmd_info {
 342         struct task_struct *task;
 343         u32 result;
 344         int status;
 345 };
 346
 347 static void sync_completion(struct nvme_queue *nvmeq, void *ctx,
 348                                                 struct nvme_completion *cqe)
 349 {
 350         struct sync_cmd_info *cmdinfo = ctx;
 351         cmdinfo->result = le32_to_cpup(&cqe->result);
 352         cmdinfo->status = le16_to_cpup(&cqe->status) >> 1;
 353         wake_up_process(cmdinfo->task);
 354 }
 355
 356 typedef void (*completion_fn)(struct nvme_queue *, void *,
 357                                                 struct nvme_completion *);
 358
 359 static irqreturn_t nvme_process_cq(struct nvme_queue *nvmeq)
 360 {
 361         u16 head, cycle;
 362
 363         static const completion_fn completions[4] = {
 364                 [sync_completion_id] = sync_completion,
 365                 [bio_completion_id]  = bio_completion,
 366         };
 367
 368         head = nvmeq->cq_head;
 369         cycle = nvmeq->cq_cycle;
 370
 371         for (;;) {
 372                 unsigned long data;
 373                 void *ptr;
 374                 unsigned char handler;
 375                 struct nvme_completion cqe = nvmeq->cqes[head];
 376                 if ((le16_to_cpu(cqe.status) & 1) != cycle)
 377                         break;
 378                 nvmeq->sq_head = le16_to_cpu(cqe.sq_head);
 379                 if (++head == nvmeq->q_depth) {
 380                         head = 0;
 381                         cycle = !cycle;
 382                 }
 383
 384                 data = free_cmdid(nvmeq, cqe.command_id);
 385                 handler = data & 3;
 386                 ptr = (void *)(data & ~3UL);
 387                 completions[handler](nvmeq, ptr, &cqe);
 388         }
 389
 390         /* If the controller ignores the cq head doorbell and continuously
 391          * writes to the queue, it is theoretically possible to wrap around
 392          * the queue twice and mistakenly return IRQ_NONE.  Linux only
 393          * requires that 0.1% of your interrupts are handled, so this isn't
 394          * a big problem.
 395          */
 396         if (head == nvmeq->cq_head && cycle == nvmeq->cq_cycle)
 397                 return IRQ_NONE;
 398
 399         writel(head, nvmeq->q_db + 1);
 400         nvmeq->cq_head = head;
 401         nvmeq->cq_cycle = cycle;
 402
 403         return IRQ_HANDLED;
 404 }
 405
 406 static irqreturn_t nvme_irq(int irq, void *data)
 407 {
 408         return nvme_process_cq(data);
 409 }
 410
 411 /*
 412  * Returns 0 on success.  If the result is negative, it's a Linux error code;
 413  * if the result is positive, it's an NVM Express status code
 414  */
 415 static int nvme_submit_sync_cmd(struct nvme_queue *q, struct nvme_command *cmd,
 416                                                                 u32 *result)
 417 {
 418         int cmdid;
 419         struct sync_cmd_info cmdinfo;
 420
 421         cmdinfo.task = current;
 422         cmdinfo.status = -EINTR;
 423
 424         cmdid = alloc_cmdid_killable(q, &cmdinfo, sync_completion_id);
 425         if (cmdid < 0)
 426                 return cmdid;
 427         cmd->common.command_id = cmdid;
 428
 429         set_current_state(TASK_UNINTERRUPTIBLE);
 430         nvme_submit_cmd(q, cmd);
 431         schedule();
 432
 433         if (result)
 434                 *result = cmdinfo.result;
 435
 436         return cmdinfo.status;
 437 }
 438
 439 static int nvme_submit_admin_cmd(struct nvme_dev *dev, struct nvme_command *cmd,
 440                                                                 u32 *result)
 441 {
 442         return nvme_submit_sync_cmd(dev->queues[0], cmd, result);
 443 }
 444
 445 static int adapter_delete_queue(struct nvme_dev *dev, u8 opcode, u16 id)
 446 {
 447         int status;
 448         struct nvme_command c;
 449
 450         memset(&c, 0, sizeof(c));
 451         c.delete_queue.opcode = opcode;
 452         c.delete_queue.qid = cpu_to_le16(id);
 453
 454         status = nvme_submit_admin_cmd(dev, &c, NULL);
 455         if (status)
 456                 return -EIO;
 457         return 0;
 458 }
 459
 460 static int adapter_alloc_cq(struct nvme_dev *dev, u16 qid,
 461                                                 struct nvme_queue *nvmeq)
 462 {
 463         int status;
 464         struct nvme_command c;
 465         int flags = NVME_QUEUE_PHYS_CONTIG | NVME_CQ_IRQ_ENABLED;
 466
 467         memset(&c, 0, sizeof(c));
 468         c.create_cq.opcode = nvme_admin_create_cq;
 469         c.create_cq.prp1 = cpu_to_le64(nvmeq->cq_dma_addr);
 470         c.create_cq.cqid = cpu_to_le16(qid);
 471         c.create_cq.qsize = cpu_to_le16(nvmeq->q_depth - 1);
 472         c.create_cq.cq_flags = cpu_to_le16(flags);
 473         c.create_cq.irq_vector = cpu_to_le16(nvmeq->cq_vector);
 474
 475         status = nvme_submit_admin_cmd(dev, &c, NULL);
 476         if (status)
 477                 return -EIO;
 478         return 0;
 479 }
 480
 481 static int adapter_alloc_sq(struct nvme_dev *dev, u16 qid,
 482                                                 struct nvme_queue *nvmeq)
 483 {
 484         int status;
 485         struct nvme_command c;
 486         int flags = NVME_QUEUE_PHYS_CONTIG | NVME_SQ_PRIO_MEDIUM;
 487
 488         memset(&c, 0, sizeof(c));
 489         c.create_sq.opcode = nvme_admin_create_sq;
 490         c.create_sq.prp1 = cpu_to_le64(nvmeq->sq_dma_addr);
 491         c.create_sq.sqid = cpu_to_le16(qid);
 492         c.create_sq.qsize = cpu_to_le16(nvmeq->q_depth - 1);
 493         c.create_sq.sq_flags = cpu_to_le16(flags);
 494         c.create_sq.cqid = cpu_to_le16(qid);
 495
 496         status = nvme_submit_admin_cmd(dev, &c, NULL);
 497         if (status)
 498                 return -EIO;
 499         return 0;
 500 }
 501
 502 static int adapter_delete_cq(struct nvme_dev *dev, u16 cqid)
 503 {
 504         return adapter_delete_queue(dev, nvme_admin_delete_cq, cqid);
 505 }
 506
 507 static int adapter_delete_sq(struct nvme_dev *dev, u16 sqid)
 508 {
 509         return adapter_delete_queue(dev, nvme_admin_delete_sq, sqid);
 510 }
 511
 512 static void nvme_free_queue(struct nvme_dev *dev, int qid)
 513 {
 514         struct nvme_queue *nvmeq = dev->queues[qid];
 515
 516         free_irq(dev->entry[nvmeq->cq_vector].vector, nvmeq);
 517
 518         /* Don't tell the adapter to delete the admin queue */
 519         if (qid) {
 520                 adapter_delete_sq(dev, qid);
 521                 adapter_delete_cq(dev, qid);
 522         }
 523
 524         dma_free_coherent(nvmeq->q_dmadev, CQ_SIZE(nvmeq->q_depth),
 525                                 (void *)nvmeq->cqes, nvmeq->cq_dma_addr);
 526         dma_free_coherent(nvmeq->q_dmadev, SQ_SIZE(nvmeq->q_depth),
 527                                         nvmeq->sq_cmds, nvmeq->sq_dma_addr);
 528         kfree(nvmeq);
 529 }
 530
 531 static struct nvme_queue *nvme_alloc_queue(struct nvme_dev *dev, int qid,
 532                                                         int depth, int vector)
 533 {
 534         struct device *dmadev = &dev->pci_dev->dev;
 535         unsigned extra = (depth + BITS_TO_LONGS(depth)) * sizeof(long);
 536         struct nvme_queue *nvmeq = kzalloc(sizeof(*nvmeq) + extra, GFP_KERNEL);
 537         if (!nvmeq)
 538                 return NULL;
 539
 540         nvmeq->cqes = dma_alloc_coherent(dmadev, CQ_SIZE(depth),
 541                                         &nvmeq->cq_dma_addr, GFP_KERNEL);
 542         if (!nvmeq->cqes)
 543                 goto free_nvmeq;
 544         memset((void *)nvmeq->cqes, 0, CQ_SIZE(depth));
 545
 546         nvmeq->sq_cmds = dma_alloc_coherent(dmadev, SQ_SIZE(depth),
 547                                         &nvmeq->sq_dma_addr, GFP_KERNEL);
 548         if (!nvmeq->sq_cmds)
 549                 goto free_cqdma;
 550
 551         nvmeq->q_dmadev = dmadev;
 552         spin_lock_init(&nvmeq->q_lock);
 553         nvmeq->cq_head = 0;
 554         nvmeq->cq_cycle = 1;
 555         init_waitqueue_head(&nvmeq->sq_full);
 556         bio_list_init(&nvmeq->sq_cong);
 557         nvmeq->q_db = &dev->dbs[qid * 2];
 558         nvmeq->q_depth = depth;
 559         nvmeq->cq_vector = vector;
 560
 561         return nvmeq;
 562
 563  free_cqdma:
 564         dma_free_coherent(dmadev, CQ_SIZE(nvmeq->q_depth), (void *)nvmeq->cqes,
 565                                                         nvmeq->cq_dma_addr);
 566  free_nvmeq:
 567         kfree(nvmeq);
 568         return NULL;
 569 }
 570
 571 static int queue_request_irq(struct nvme_dev *dev, struct nvme_queue *nvmeq,
 572                                                         const char *name)
 573 {
 574         return request_irq(dev->entry[nvmeq->cq_vector].vector, nvme_irq,
 575                                 IRQF_DISABLED | IRQF_SHARED, name, nvmeq);
 576 }
 577
 578 static __devinit struct nvme_queue *nvme_create_queue(struct nvme_dev *dev,
 579                                         int qid, int cq_size, int vector)
 580 {
 581         int result;
 582         struct nvme_queue *nvmeq = nvme_alloc_queue(dev, qid, cq_size, vector);
 583
 584         result = adapter_alloc_cq(dev, qid, nvmeq);
 585         if (result < 0)
 586                 goto free_nvmeq;
 587
 588         result = adapter_alloc_sq(dev, qid, nvmeq);
 589         if (result < 0)
 590                 goto release_cq;
 591
 592         result = queue_request_irq(dev, nvmeq, "nvme");
 593         if (result < 0)
 594                 goto release_sq;
 595
 596         return nvmeq;
 597
 598  release_sq:
 599         adapter_delete_sq(dev, qid);
 600  release_cq:
 601         adapter_delete_cq(dev, qid);
 602  free_nvmeq:
 603         dma_free_coherent(nvmeq->q_dmadev, CQ_SIZE(nvmeq->q_depth),
 604                                 (void *)nvmeq->cqes, nvmeq->cq_dma_addr);
 605         dma_free_coherent(nvmeq->q_dmadev, SQ_SIZE(nvmeq->q_depth),
 606                                         nvmeq->sq_cmds, nvmeq->sq_dma_addr);
 607         kfree(nvmeq);
 608         return NULL;
 609 }
 610
 611 static int __devinit nvme_configure_admin_queue(struct nvme_dev *dev)
 612 {
 613         int result;
 614         u32 aqa;
 615         struct nvme_queue *nvmeq;
 616
 617         dev->dbs = ((void __iomem *)dev->bar) + 4096;
 618
 619         nvmeq = nvme_alloc_queue(dev, 0, 64, 0);
 620
 621         aqa = nvmeq->q_depth - 1;
 622         aqa |= aqa << 16;
 623
 624         dev->ctrl_config = NVME_CC_ENABLE | NVME_CC_CSS_NVM;
 625         dev->ctrl_config |= (PAGE_SHIFT - 12) << NVME_CC_MPS_SHIFT;
 626         dev->ctrl_config |= NVME_CC_ARB_RR | NVME_CC_SHN_NONE;
 627
 628         writel(aqa, &dev->bar->aqa);
 629         writeq(nvmeq->sq_dma_addr, &dev->bar->asq);
 630         writeq(nvmeq->cq_dma_addr, &dev->bar->acq);
 631         writel(dev->ctrl_config, &dev->bar->cc);
 632
 633         while (!(readl(&dev->bar->csts) & NVME_CSTS_RDY)) {
 634                 msleep(100);
 635                 if (fatal_signal_pending(current))
 636                         return -EINTR;
 637         }
 638
 639         result = queue_request_irq(dev, nvmeq, "nvme admin");
 640         dev->queues[0] = nvmeq;
 641         return result;
 642 }
 643
 644 static int nvme_identify(struct nvme_ns *ns, void __user *addr, int cns)
 645 {
 646         struct nvme_dev *dev = ns->dev;
 647         int status;
 648         struct nvme_command c;
 649         void *page;
 650         dma_addr_t dma_addr;
 651
 652         page = dma_alloc_coherent(&dev->pci_dev->dev, 4096, &dma_addr,
 653                                                                 GFP_KERNEL);
 654
 655         memset(&c, 0, sizeof(c));
 656         c.identify.opcode = nvme_admin_identify;
 657         c.identify.nsid = cns ? 0 : cpu_to_le32(ns->ns_id);
 658         c.identify.prp1 = cpu_to_le64(dma_addr);
 659         c.identify.cns = cpu_to_le32(cns);
 660
 661         status = nvme_submit_admin_cmd(dev, &c, NULL);
 662
 663         if (status)
 664                 status = -EIO;
 665         else if (copy_to_user(addr, page, 4096))
 666                 status = -EFAULT;
 667
 668         dma_free_coherent(&dev->pci_dev->dev, 4096, page, dma_addr);
 669
 670         return status;
 671 }
 672
 673 static int nvme_get_range_type(struct nvme_ns *ns, void __user *addr)
 674 {
 675         struct nvme_dev *dev = ns->dev;
 676         int status;
 677         struct nvme_command c;
 678         void *page;
 679         dma_addr_t dma_addr;
 680
 681         page = dma_alloc_coherent(&dev->pci_dev->dev, 4096, &dma_addr,
 682                                                                 GFP_KERNEL);
 683
 684         memset(&c, 0, sizeof(c));
 685         c.features.opcode = nvme_admin_get_features;
 686         c.features.nsid = cpu_to_le32(ns->ns_id);
 687         c.features.prp1 = cpu_to_le64(dma_addr);
 688         c.features.fid = cpu_to_le32(NVME_FEAT_LBA_RANGE);
 689
 690         status = nvme_submit_admin_cmd(dev, &c, NULL);
 691
 692         /* XXX: Assuming first range for now */
 693         if (status)
 694                 status = -EIO;
 695         else if (copy_to_user(addr, page, 64))
 696                 status = -EFAULT;
 697
 698         dma_free_coherent(&dev->pci_dev->dev, 4096, page, dma_addr);
 699
 700         return status;
 701 }
 702
 703 static int nvme_ioctl(struct block_device *bdev, fmode_t mode, unsigned int cmd,
 704                                                         unsigned long arg)
 705 {
 706         struct nvme_ns *ns = bdev->bd_disk->private_data;
 707
 708         switch (cmd) {
 709         case NVME_IOCTL_IDENTIFY_NS:
 710                 return nvme_identify(ns, (void __user *)arg, 0);
 711         case NVME_IOCTL_IDENTIFY_CTRL:
 712                 return nvme_identify(ns, (void __user *)arg, 1);
 713         case NVME_IOCTL_GET_RANGE_TYPE:
 714                 return nvme_get_range_type(ns, (void __user *)arg);
 715         default:
 716                 return -ENOTTY;
 717         }
 718 }
 719
 720 static const struct block_device_operations nvme_fops = {
 721         .owner          = THIS_MODULE,
 722         .ioctl          = nvme_ioctl,
 723 };
 724
 725 static struct nvme_ns *nvme_alloc_ns(struct nvme_dev *dev, int index,
 726                         struct nvme_id_ns *id, struct nvme_lba_range_type *rt)
 727 {
 728         struct nvme_ns *ns;
 729         struct gendisk *disk;
 730         int lbaf;
 731
 732         if (rt->attributes & NVME_LBART_ATTRIB_HIDE)
 733                 return NULL;
 734
 735         ns = kzalloc(sizeof(*ns), GFP_KERNEL);
 736         if (!ns)
 737                 return NULL;
 738         ns->queue = blk_alloc_queue(GFP_KERNEL);
 739         if (!ns->queue)
 740                 goto out_free_ns;
 741         ns->queue->queue_flags = QUEUE_FLAG_DEFAULT | QUEUE_FLAG_NOMERGES |
 742                                 QUEUE_FLAG_NONROT | QUEUE_FLAG_DISCARD;
 743         blk_queue_make_request(ns->queue, nvme_make_request);
 744         ns->dev = dev;
 745         ns->queue->queuedata = ns;
 746
 747         disk = alloc_disk(NVME_MINORS);
 748         if (!disk)
 749                 goto out_free_queue;
 750         ns->ns_id = index;
 751         ns->disk = disk;
 752         lbaf = id->flbas & 0xf;
 753         ns->lba_shift = id->lbaf[lbaf].ds;
 754
 755         disk->major = nvme_major;
 756         disk->minors = NVME_MINORS;
 757         disk->first_minor = NVME_MINORS * index;
 758         disk->fops = &nvme_fops;
 759         disk->private_data = ns;
 760         disk->queue = ns->queue;
 761         sprintf(disk->disk_name, "nvme%dn%d", dev->instance, index);
 762         set_capacity(disk, le64_to_cpup(&id->nsze) << (ns->lba_shift - 9));
 763
 764         return ns;
 765
 766  out_free_queue:
 767         blk_cleanup_queue(ns->queue);
 768  out_free_ns:
 769         kfree(ns);
 770         return NULL;
 771 }
 772
 773 static void nvme_ns_free(struct nvme_ns *ns)
 774 {
 775         put_disk(ns->disk);
 776         blk_cleanup_queue(ns->queue);
 777         kfree(ns);
 778 }
 779
 780 static int set_queue_count(struct nvme_dev *dev, int count)
 781 {
 782         int status;
 783         u32 result;
 784         struct nvme_command c;
 785         u32 q_count = (count - 1) | ((count - 1) << 16);
 786
 787         memset(&c, 0, sizeof(c));
 788         c.features.opcode = nvme_admin_get_features;
 789         c.features.fid = cpu_to_le32(NVME_FEAT_NUM_QUEUES);
 790         c.features.dword11 = cpu_to_le32(q_count);
 791
 792         status = nvme_submit_admin_cmd(dev, &c, &result);
 793         if (status)
 794                 return -EIO;
 795         return min(result & 0xffff, result >> 16) + 1;
 796 }
 797
 798 /* XXX: Create per-CPU queues */
 799 static int __devinit nvme_setup_io_queues(struct nvme_dev *dev)
 800 {
 801         int this_cpu;
 802
 803         set_queue_count(dev, 1);
 804
 805         this_cpu = get_cpu();
 806         dev->queues[1] = nvme_create_queue(dev, 1, NVME_Q_DEPTH, this_cpu);
 807         put_cpu();
 808         if (!dev->queues[1])
 809                 return -ENOMEM;
 810         dev->queue_count++;
 811
 812         return 0;
 813 }
 814
 815 static void nvme_free_queues(struct nvme_dev *dev)
 816 {
 817         int i;
 818
 819         for (i = dev->queue_count - 1; i >= 0; i--)
 820                 nvme_free_queue(dev, i);
 821 }
 822
 823 static int __devinit nvme_dev_add(struct nvme_dev *dev)
 824 {
 825         int res, nn, i;
 826         struct nvme_ns *ns, *next;
 827         void *id;
 828         dma_addr_t dma_addr;
 829         struct nvme_command cid, crt;
 830
 831         res = nvme_setup_io_queues(dev);
 832         if (res)
 833                 return res;
 834
 835         /* XXX: Switch to a SG list once prp2 works */
 836         id = dma_alloc_coherent(&dev->pci_dev->dev, 8192, &dma_addr,
 837                                                                 GFP_KERNEL);
 838
 839         memset(&cid, 0, sizeof(cid));
 840         cid.identify.opcode = nvme_admin_identify;
 841         cid.identify.nsid = 0;
 842         cid.identify.prp1 = cpu_to_le64(dma_addr);
 843         cid.identify.cns = cpu_to_le32(1);
 844
 845         res = nvme_submit_admin_cmd(dev, &cid, NULL);
 846         if (res) {
 847                 res = -EIO;
 848                 goto out_free;
 849         }
 850
 851         nn = le32_to_cpup(&((struct nvme_id_ctrl *)id)->nn);
 852
 853         cid.identify.cns = 0;
 854         memset(&crt, 0, sizeof(crt));
 855         crt.features.opcode = nvme_admin_get_features;
 856         crt.features.prp1 = cpu_to_le64(dma_addr + 4096);
 857         crt.features.fid = cpu_to_le32(NVME_FEAT_LBA_RANGE);
 858
 859         for (i = 0; i < nn; i++) {
 860                 cid.identify.nsid = cpu_to_le32(i);
 861                 res = nvme_submit_admin_cmd(dev, &cid, NULL);
 862                 if (res)
 863                         continue;
 864
 865                 if (((struct nvme_id_ns *)id)->ncap == 0)
 866                         continue;
 867
 868                 crt.features.nsid = cpu_to_le32(i);
 869                 res = nvme_submit_admin_cmd(dev, &crt, NULL);
 870                 if (res)
 871                         continue;
 872
 873                 ns = nvme_alloc_ns(dev, i, id, id + 4096);
 874                 if (ns)
 875                         list_add_tail(&ns->list, &dev->namespaces);
 876         }
 877         list_for_each_entry(ns, &dev->namespaces, list)
 878                 add_disk(ns->disk);
 879
 880         dma_free_coherent(&dev->pci_dev->dev, 4096, id, dma_addr);
 881         return 0;
 882
 883  out_free:
 884         list_for_each_entry_safe(ns, next, &dev->namespaces, list) {
 885                 list_del(&ns->list);
 886                 nvme_ns_free(ns);
 887         }
 888
 889         dma_free_coherent(&dev->pci_dev->dev, 4096, id, dma_addr);
 890         return res;
 891 }
 892
 893 static int nvme_dev_remove(struct nvme_dev *dev)
 894 {
 895         struct nvme_ns *ns, *next;
 896
 897         /* TODO: wait all I/O finished or cancel them */
 898
 899         list_for_each_entry_safe(ns, next, &dev->namespaces, list) {
 900                 list_del(&ns->list);
 901                 del_gendisk(ns->disk);
 902                 nvme_ns_free(ns);
 903         }
 904
 905         nvme_free_queues(dev);
 906
 907         return 0;
 908 }
 909
 910 /* XXX: Use an ida or something to let remove / add work correctly */
 911 static void nvme_set_instance(struct nvme_dev *dev)
 912 {
 913         static int instance;
 914         dev->instance = instance++;
 915 }
 916
 917 static void nvme_release_instance(struct nvme_dev *dev)
 918 {
 919 }
 920
 921 static int __devinit nvme_probe(struct pci_dev *pdev,
 922                                                 const struct pci_device_id *id)
 923 {
 924         int result = -ENOMEM;
 925         struct nvme_dev *dev;
 926
 927         dev = kzalloc(sizeof(*dev), GFP_KERNEL);
 928         if (!dev)
 929                 return -ENOMEM;
 930         dev->entry = kcalloc(num_possible_cpus(), sizeof(*dev->entry),
 931                                                                 GFP_KERNEL);
 932         if (!dev->entry)
 933                 goto free;
 934         dev->queues = kcalloc(2, sizeof(void *), GFP_KERNEL);
 935         if (!dev->queues)
 936                 goto free;
 937
 938         INIT_LIST_HEAD(&dev->namespaces);
 939         dev->pci_dev = pdev;
 940         pci_set_drvdata(pdev, dev);
 941         dma_set_mask(&dev->pci_dev->dev, DMA_BIT_MASK(64));
 942         nvme_set_instance(dev);
 943
 944         dev->bar = ioremap(pci_resource_start(pdev, 0), 8192);
 945         if (!dev->bar) {
 946                 result = -ENOMEM;
 947                 goto disable;
 948         }
 949
 950         result = nvme_configure_admin_queue(dev);
 951         if (result)
 952                 goto unmap;
 953         dev->queue_count++;
 954
 955         result = nvme_dev_add(dev);
 956         if (result)
 957                 goto delete;
 958         return 0;
 959
 960  delete:
 961         nvme_free_queues(dev);
 962  unmap:
 963         iounmap(dev->bar);
 964  disable:
 965         pci_disable_msix(pdev);
 966         nvme_release_instance(dev);
 967  free:
 968         kfree(dev->queues);
 969         kfree(dev->entry);
 970         kfree(dev);
 971         return result;
 972 }
 973
 974 static void __devexit nvme_remove(struct pci_dev *pdev)
 975 {
 976         struct nvme_dev *dev = pci_get_drvdata(pdev);
 977         nvme_dev_remove(dev);
 978         pci_disable_msix(pdev);
 979         iounmap(dev->bar);
 980         nvme_release_instance(dev);
 981         kfree(dev->queues);
 982         kfree(dev->entry);
 983         kfree(dev);
 984 }
 985
 986 /* These functions are yet to be implemented */
 987 #define nvme_error_detected NULL
 988 #define nvme_dump_registers NULL
 989 #define nvme_link_reset NULL
 990 #define nvme_slot_reset NULL
 991 #define nvme_error_resume NULL
 992 #define nvme_suspend NULL
 993 #define nvme_resume NULL
 994
 995 static struct pci_error_handlers nvme_err_handler = {
 996         .error_detected = nvme_error_detected,
 997         .mmio_enabled   = nvme_dump_registers,
 998         .link_reset     = nvme_link_reset,
 999         .slot_reset     = nvme_slot_reset,
1000         .resume         = nvme_error_resume,
1001 };
1002
1003 /* Move to pci_ids.h later */
1004 #define PCI_CLASS_STORAGE_EXPRESS       0x010802
1005
1006 static DEFINE_PCI_DEVICE_TABLE(nvme_id_table) = {
1007         { PCI_DEVICE_CLASS(PCI_CLASS_STORAGE_EXPRESS, 0xffffff) },
1008         { 0, }
1009 };
1010 MODULE_DEVICE_TABLE(pci, nvme_id_table);
1011
1012 static struct pci_driver nvme_driver = {
1013         .name           = "nvme",
1014         .id_table       = nvme_id_table,
1015         .probe          = nvme_probe,
1016         .remove         = __devexit_p(nvme_remove),
1017         .suspend        = nvme_suspend,
1018         .resume         = nvme_resume,
1019         .err_handler    = &nvme_err_handler,
1020 };
1021
1022 static int __init nvme_init(void)
1023 {
1024         int result;
1025
1026         nvme_major = register_blkdev(nvme_major, "nvme");
1027         if (nvme_major <= 0)
1028                 return -EBUSY;
1029
1030         result = pci_register_driver(&nvme_driver);
1031         if (!result)
1032                 return 0;
1033
1034         unregister_blkdev(nvme_major, "nvme");
1035         return result;
1036 }
1037
1038 static void __exit nvme_exit(void)
1039 {
1040         pci_unregister_driver(&nvme_driver);
1041         unregister_blkdev(nvme_major, "nvme");
1042 }
1043
1044 MODULE_AUTHOR("Matthew Wilcox <willy@linux.intel.com>");
1045 MODULE_LICENSE("GPL");
1046 MODULE_VERSION("0.1");
1047 module_init(nvme_init);
1048 module_exit(nvme_exit);