diff options
Diffstat (limited to 'drivers/block/nvme.c')
| -rw-r--r-- | drivers/block/nvme.c | 1739 |
1 files changed, 1739 insertions, 0 deletions
diff --git a/drivers/block/nvme.c b/drivers/block/nvme.c new file mode 100644 index 000000000000..c1dc4d86c221 --- /dev/null +++ b/drivers/block/nvme.c @@ -0,0 +1,1739 @@ +/* + * 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/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 +#define NVME_IO_TIMEOUT (5 * HZ) +#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; + +/* + * Represents an NVM Express device. Each nvme_dev is a PCI function. + */ +struct nvme_dev { + struct list_head node; + struct nvme_queue **queues; + u32 __iomem *dbs; + struct pci_dev *pci_dev; + struct dma_pool *prp_page_pool; + struct dma_pool *prp_small_pool; + int instance; + int queue_count; + int db_stride; + 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; + 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; + 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); +} + +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)]; +} + +/** + * 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; + } + *fn = info[cmdid].fn; + ctx = info[cmdid].ctx; + info[cmdid].fn = special_completion; + info[cmdid].ctx = CMD_CTX_COMPLETED; + clear_bit(cmdid, nvmeq->cmdid_data); + wake_up(&nvmeq->sq_full); + return ctx; +} + +static void *cancel_cmdid(struct nvme_queue *nvmeq, int cmdid, + nvme_completion_fn *fn) +{ + void *ctx; + struct nvme_cmd_info *info = nvme_cmd_info(nvmeq); + if (fn) + *fn = info[cmdid].fn; + ctx = info[cmdid].ctx; + info[cmdid].fn = special_completion; + info[cmdid].ctx = CMD_CTX_CANCELLED; + return ctx; +} + +static struct nvme_queue *get_nvmeq(struct nvme_dev *dev) +{ + return dev->queues[get_cpu() + 1]; +} + +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; + 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; +} + +/* + * The nvme_iod describes the data in an I/O, including the list of PRP + * entries. You can't see it in this data structure because C doesn't let + * me express that. Use nvme_alloc_iod to ensure there's enough space + * allocated to store the PRP list. + */ +struct nvme_iod { + void *private; /* For the use of the submitter of the I/O */ + int npages; /* In the PRP list. 0 means small pool in use */ + int offset; /* Of PRP list */ + int nents; /* Used in scatterlist */ + int length; /* Of data, in bytes */ + dma_addr_t first_dma; + struct scatterlist sg[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; + } + + return iod; +} + +static 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 requeue_bio(struct nvme_dev *dev, struct bio *bio) +{ + struct nvme_queue *nvmeq = get_nvmeq(dev); + if (bio_list_empty(&nvmeq->sq_cong)) + add_wait_queue(&nvmeq->sq_full, &nvmeq->sq_cong_wait); + bio_list_add(&nvmeq->sq_cong, bio); + put_nvmeq(nvmeq); + wake_up_process(nvme_thread); +} + +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; + + dma_unmap_sg(&dev->pci_dev->dev, iod->sg, iod->nents, + bio_data_dir(bio) ? DMA_TO_DEVICE : DMA_FROM_DEVICE); + nvme_free_iod(dev, iod); + if (status) { + bio_endio(bio, -EIO); + } else if (bio->bi_vcnt > bio->bi_idx) { + requeue_bio(dev, bio); + } else { + bio_endio(bio, 0); + } +} + +/* length is in bytes. gfp flags indicates whether we may sleep. */ +static 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; +} + +/* 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 device *dev, struct nvme_iod *iod, + struct bio *bio, enum dma_data_direction dma_dir, int psegs) +{ + struct bio_vec *bvec, *bvprv = NULL; + struct scatterlist *sg = NULL; + int i, old_idx, length = 0, nsegs = 0; + + sg_init_table(iod->sg, psegs); + old_idx = bio->bi_idx; + bio_for_each_segment(bvec, bio, i) { + if (bvprv && BIOVEC_PHYS_MERGEABLE(bvprv, bvec)) { + sg->length += bvec->bv_len; + } else { + if (bvprv && BIOVEC_NOT_VIRT_MERGEABLE(bvprv, bvec)) + break; + sg = sg ? sg + 1 : iod->sg; + sg_set_page(sg, bvec->bv_page, bvec->bv_len, + bvec->bv_offset); + nsegs++; + } + length += bvec->bv_len; + bvprv = bvec; + } + bio->bi_idx = i; + iod->nents = nsegs; + sg_mark_end(sg); + if (dma_map_sg(dev, iod->sg, iod->nents, dma_dir) == 0) { + bio->bi_idx = old_idx; + return -ENOMEM; + } + return length; +} + +static int nvme_submit_flush(struct nvme_queue *nvmeq, struct nvme_ns *ns, + int cmdid) +{ + struct nvme_command *cmnd = &nvmeq->sq_cmds[nvmeq->sq_tail]; + + memset(cmnd, 0, sizeof(*cmnd)); + cmnd->common.opcode = nvme_cmd_flush; + cmnd->common.command_id = cmdid; + cmnd->common.nsid = cpu_to_le32(ns->ns_id); + + if (++nvmeq->sq_tail == nvmeq->q_depth) + nvmeq->sq_tail = 0; + writel(nvmeq->sq_tail, nvmeq->q_db); + + return 0; +} + +static int nvme_submit_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 = -ENOMEM; + 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; + } + + iod = nvme_alloc_iod(psegs, bio->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_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->q_dmadev, iod, bio, dma_dir, psegs); + if (result < 0) + goto free_iod; + 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(bio->bi_sector >> (ns->lba_shift - 9)); + 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); + + bio->bi_sector += length >> 9; + + if (++nvmeq->sq_tail == nvmeq->q_depth) + nvmeq->sq_tail = 0; + writel(nvmeq->sq_tail, nvmeq->q_db); + + return 0; + + free_iod: + nvme_free_iod(nvmeq->dev, iod); + nomem: + return result; +} + +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; + + spin_lock_irq(&nvmeq->q_lock); + if (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); + } + + spin_unlock_irq(&nvmeq->q_lock); + put_nvmeq(nvmeq); +} + +static irqreturn_t 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 IRQ_NONE; + + writel(head, nvmeq->q_db + (1 << nvmeq->dev->db_stride)); + nvmeq->cq_head = head; + nvmeq->cq_phase = phase; + + return IRQ_HANDLED; +} + +static irqreturn_t nvme_irq(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(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 + */ +static 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(); + + 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, 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); +} + +static 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); +} + +static int nvme_get_features(struct nvme_dev *dev, unsigned fid, + unsigned dword11, dma_addr_t dma_addr) +{ + struct nvme_command c; + + memset(&c, 0, sizeof(c)); + c.features.opcode = nvme_admin_get_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, NULL); +} + +static 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); +} + +static void nvme_free_queue(struct nvme_dev *dev, int qid) +{ + struct nvme_queue *nvmeq = dev->queues[qid]; + int vector = dev->entry[nvmeq->cq_vector].vector; + + 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); + } + + 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 / 8) + (depth * sizeof(struct nvme_cmd_info)); + 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; + + 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, + 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 ERR_PTR(-ENOMEM); + + 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 ERR_PTR(result); +} + +static int __devinit nvme_configure_admin_queue(struct nvme_dev *dev) +{ + int result; + u32 aqa; + u64 cap; + unsigned long timeout; + 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; + dev->ctrl_config |= NVME_CC_IOSQES | NVME_CC_IOCQES; + + 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); + + cap = readq(&dev->bar->cap); + timeout = ((NVME_CAP_TIMEOUT(cap) + 1) * HZ / 2) + jiffies; + dev->db_stride = NVME_CAP_STRIDE(cap); + + while (!(readl(&dev->bar->csts) & NVME_CSTS_RDY)) { + 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; + } + } + + result = queue_request_irq(dev, nvmeq, "nvme admin"); + dev->queues[0] = nvmeq; + return result; +} + +static 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) + return ERR_PTR(-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; + } + + 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(int, 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); +} + +static 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; + int status; + struct nvme_iod *iod; + + if (copy_from_user(&io, uio, sizeof(io))) + return -EFAULT; + length = (io.nblocks + 1) << ns->lba_shift; + + 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_le16(io.dsmgmt); + c.rw.reftag = io.reftag; + c.rw.apptag = io.apptag; + c.rw.appmask = io.appmask; + /* XXX: metadata */ + 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 + status = nvme_submit_sync_cmd(nvmeq, &c, NULL, NVME_IO_TIMEOUT); + + nvme_unmap_user_pages(dev, io.opcode & 1, iod); + nvme_free_iod(dev, iod); + return status; +} + +static int nvme_user_admin_cmd(struct nvme_ns *ns, + struct nvme_admin_cmd __user *ucmd) +{ + struct nvme_dev *dev = ns->dev; + struct nvme_admin_cmd cmd; + struct nvme_command c; + int status, length; + struct nvme_iod *iod; + + 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); + } + + if (length != cmd.data_len) + status = -ENOMEM; + else + status = nvme_submit_admin_cmd(dev, &c, NULL); + + if (cmd.data_len) { + nvme_unmap_user_pages(dev, cmd.opcode & 1, iod); + nvme_free_iod(dev, iod); + } + 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: + return ns->ns_id; + case NVME_IOCTL_ADMIN_CMD: + return nvme_user_admin_cmd(ns, (void __user *)arg); + case NVME_IOCTL_SUBMIT_IO: + return nvme_submit_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_timeout_ios(struct nvme_queue *nvmeq) +{ + 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 (!time_after(now, info[cmdid].timeout)) + continue; + dev_warn(nvmeq->q_dmadev, "Timing out I/O %d\n", cmdid); + ctx = cancel_cmdid(nvmeq, cmdid, &fn); + fn(nvmeq->dev, ctx, &cqe); + } +} + +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 (nvme_submit_bio_queue(nvmeq, ns, bio)) { + bio_list_add_head(&nvmeq->sq_cong, bio); + break; + } + if (bio_list_empty(&nvmeq->sq_cong)) + remove_wait_queue(&nvmeq->sq_full, + &nvmeq->sq_cong_wait); + } +} + +static int nvme_kthread(void *data) +{ + struct nvme_dev *dev; + + while (!kthread_should_stop()) { + __set_current_state(TASK_RUNNING); + 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 (nvme_process_cq(nvmeq)) + printk("process_cq did something\n"); + nvme_timeout_ios(nvmeq); + nvme_resubmit_bios(nvmeq); + spin_unlock_irq(&nvmeq->q_lock); + } + } + spin_unlock(&dev_list_lock); + set_current_state(TASK_INTERRUPTIBLE); + schedule_timeout(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 struct nvme_ns *nvme_alloc_ns(struct nvme_dev *dev, int 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); +/* queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, 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; + + 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)); + + 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 -EIO; + return min(result & 0xffff, result >> 16) + 1; +} + +static int __devinit nvme_setup_io_queues(struct nvme_dev *dev) +{ + int result, cpu, i, nr_io_queues, db_bar_size; + + 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; + + /* Deregister the admin queue's interrupt */ + free_irq(dev->entry[0].vector, dev->queues[0]); + + db_bar_size = 4096 + ((nr_io_queues + 1) << (dev->db_stride + 3)); + if (db_bar_size > 8192) { + iounmap(dev->bar); + dev->bar = ioremap(pci_resource_start(dev->pci_dev, 0), + db_bar_size); + dev->dbs = ((void __iomem *)dev->bar) + 4096; + dev->queues[0]->q_db = dev->dbs; + } + + for (i = 0; i < nr_io_queues; i++) + dev->entry[i].entry = i; + for (;;) { + result = pci_enable_msix(dev->pci_dev, dev->entry, + nr_io_queues); + if (result == 0) { + break; + } else if (result > 0) { + nr_io_queues = result; + continue; + } else { + nr_io_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_io_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_io_queues; i++) { + dev->queues[i + 1] = nvme_create_queue(dev, i + 1, + NVME_Q_DEPTH, i); + if (IS_ERR(dev->queues[i + 1])) + return PTR_ERR(dev->queues[i + 1]); + dev->queue_count++; + } + + 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]; + } + + 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; + struct nvme_id_ns *id_ns; + void *mem; + dma_addr_t dma_addr; + + res = nvme_setup_io_queues(dev); + if (res) + return res; + + mem = dma_alloc_coherent(&dev->pci_dev->dev, 8192, &dma_addr, + GFP_KERNEL); + + res = nvme_identify(dev, 0, 1, dma_addr); + if (res) { + res = -EIO; + goto out_free; + } + + ctrl = mem; + 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)); + + 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); + if (res) + continue; + + 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); + + goto out; + + out_free: + list_for_each_entry_safe(ns, next, &dev->namespaces, list) { + list_del(&ns->list); + nvme_ns_free(ns); + } + + out: + dma_free_coherent(&dev->pci_dev->dev, 8192, mem, dma_addr); + return res; +} + +static int nvme_dev_remove(struct nvme_dev *dev) +{ + struct nvme_ns *ns, *next; + + spin_lock(&dev_list_lock); + list_del(&dev->node); + spin_unlock(&dev_list_lock); + + /* 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; +} + +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); +} + +/* 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; + + result = nvme_setup_prp_pools(dev); + if (result) + goto disable_msix; + + 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++; + + spin_lock(&dev_list_lock); + list_add(&dev->node, &dev_list); + spin_unlock(&dev_list_lock); + + result = nvme_dev_add(dev); + if (result) + goto delete; + + return 0; + + delete: + spin_lock(&dev_list_lock); + list_del(&dev->node); + spin_unlock(&dev_list_lock); + + nvme_free_queues(dev); + unmap: + iounmap(dev->bar); + disable_msix: + pci_disable_msix(pdev); + nvme_release_instance(dev); + nvme_release_prp_pools(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); + nvme_release_prp_pools(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 = -EBUSY; + + nvme_thread = kthread_run(nvme_kthread, NULL, "nvme"); + if (IS_ERR(nvme_thread)) + return PTR_ERR(nvme_thread); + + nvme_major = register_blkdev(nvme_major, "nvme"); + if (nvme_major <= 0) + goto kill_kthread; + + 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); |